[sfrench/cifs-2.6.git] / drivers / gpu / drm / i915 / display / intel_dp.c

/*
 * Copyright © 2008 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Authors:
 *    Keith Packard <keithp@keithp.com>
 *
 */

#include <linux/export.h>
#include <linux/i2c.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/types.h>

#include <asm/byteorder.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc.h>
#include <drm/drm_dp_helper.h>
#include <drm/drm_edid.h>
#include <drm/drm_hdcp.h>
#include <drm/drm_probe_helper.h>
#include <drm/i915_drm.h>

#include "i915_debugfs.h"
#include "i915_drv.h"
#include "i915_trace.h"
#include "intel_atomic.h"
#include "intel_audio.h"
#include "intel_connector.h"
#include "intel_ddi.h"
#include "intel_display_types.h"
#include "intel_dp.h"
#include "intel_dp_link_training.h"
#include "intel_dp_mst.h"
#include "intel_dpio_phy.h"
#include "intel_fifo_underrun.h"
#include "intel_hdcp.h"
#include "intel_hdmi.h"
#include "intel_hotplug.h"
#include "intel_lspcon.h"
#include "intel_lvds.h"
#include "intel_panel.h"
#include "intel_psr.h"
#include "intel_sideband.h"
#include "intel_tc.h"
#include "intel_vdsc.h"

#define DP_DPRX_ESI_LEN 14

/* DP DSC throughput values used for slice count calculations KPixels/s */
#define DP_DSC_PEAK_PIXEL_RATE                  2720000
#define DP_DSC_MAX_ENC_THROUGHPUT_0             340000
#define DP_DSC_MAX_ENC_THROUGHPUT_1             400000

/* DP DSC FEC Overhead factor = 1/(0.972261) */
#define DP_DSC_FEC_OVERHEAD_FACTOR              972261

/* Compliance test status bits  */
#define INTEL_DP_RESOLUTION_SHIFT_MASK  0
#define INTEL_DP_RESOLUTION_PREFERRED   (1 << INTEL_DP_RESOLUTION_SHIFT_MASK)
#define INTEL_DP_RESOLUTION_STANDARD    (2 << INTEL_DP_RESOLUTION_SHIFT_MASK)
#define INTEL_DP_RESOLUTION_FAILSAFE    (3 << INTEL_DP_RESOLUTION_SHIFT_MASK)

struct dp_link_dpll {
        int clock;
        struct dpll dpll;
};

static const struct dp_link_dpll g4x_dpll[] = {
        { 162000,
                { .p1 = 2, .p2 = 10, .n = 2, .m1 = 23, .m2 = 8 } },
        { 270000,
                { .p1 = 1, .p2 = 10, .n = 1, .m1 = 14, .m2 = 2 } }
};

static const struct dp_link_dpll pch_dpll[] = {
        { 162000,
                { .p1 = 2, .p2 = 10, .n = 1, .m1 = 12, .m2 = 9 } },
        { 270000,
                { .p1 = 1, .p2 = 10, .n = 2, .m1 = 14, .m2 = 8 } }
};

static const struct dp_link_dpll vlv_dpll[] = {
        { 162000,
                { .p1 = 3, .p2 = 2, .n = 5, .m1 = 3, .m2 = 81 } },
        { 270000,
                { .p1 = 2, .p2 = 2, .n = 1, .m1 = 2, .m2 = 27 } }
};

/*
 * CHV supports eDP 1.4 that have  more link rates.
 * Below only provides the fixed rate but exclude variable rate.
 */
static const struct dp_link_dpll chv_dpll[] = {
        /*
         * CHV requires to program fractional division for m2.
         * m2 is stored in fixed point format using formula below
         * (m2_int << 22) | m2_fraction
         */
        { 162000,       /* m2_int = 32, m2_fraction = 1677722 */
                { .p1 = 4, .p2 = 2, .n = 1, .m1 = 2, .m2 = 0x819999a } },
        { 270000,       /* m2_int = 27, m2_fraction = 0 */
                { .p1 = 4, .p2 = 1, .n = 1, .m1 = 2, .m2 = 0x6c00000 } },
};

/* Constants for DP DSC configurations */
static const u8 valid_dsc_bpp[] = {6, 8, 10, 12, 15};

/* With Single pipe configuration, HW is capable of supporting maximum
 * of 4 slices per line.
 */
static const u8 valid_dsc_slicecount[] = {1, 2, 4};

/**
 * intel_dp_is_edp - is the given port attached to an eDP panel (either CPU or PCH)
 * @intel_dp: DP struct
 *
 * If a CPU or PCH DP output is attached to an eDP panel, this function
 * will return true, and false otherwise.
 */
bool intel_dp_is_edp(struct intel_dp *intel_dp)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);

        return intel_dig_port->base.type == INTEL_OUTPUT_EDP;
}

static struct intel_dp *intel_attached_dp(struct drm_connector *connector)
{
        return enc_to_intel_dp(&intel_attached_encoder(connector)->base);
}

static void intel_dp_link_down(struct intel_encoder *encoder,
                               const struct intel_crtc_state *old_crtc_state);
static bool edp_panel_vdd_on(struct intel_dp *intel_dp);
static void edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync);
static void vlv_init_panel_power_sequencer(struct intel_encoder *encoder,
                                           const struct intel_crtc_state *crtc_state);
static void vlv_steal_power_sequencer(struct drm_i915_private *dev_priv,
                                      enum pipe pipe);
static void intel_dp_unset_edid(struct intel_dp *intel_dp);

/* update sink rates from dpcd */
static void intel_dp_set_sink_rates(struct intel_dp *intel_dp)
{
        static const int dp_rates[] = {
                162000, 270000, 540000, 810000
        };
        int i, max_rate;

        max_rate = drm_dp_bw_code_to_link_rate(intel_dp->dpcd[DP_MAX_LINK_RATE]);

        for (i = 0; i < ARRAY_SIZE(dp_rates); i++) {
                if (dp_rates[i] > max_rate)
                        break;
                intel_dp->sink_rates[i] = dp_rates[i];
        }

        intel_dp->num_sink_rates = i;
}

/* Get length of rates array potentially limited by max_rate. */
static int intel_dp_rate_limit_len(const int *rates, int len, int max_rate)
{
        int i;

        /* Limit results by potentially reduced max rate */
        for (i = 0; i < len; i++) {
                if (rates[len - i - 1] <= max_rate)
                        return len - i;
        }

        return 0;
}

/* Get length of common rates array potentially limited by max_rate. */
static int intel_dp_common_len_rate_limit(const struct intel_dp *intel_dp,
                                          int max_rate)
{
        return intel_dp_rate_limit_len(intel_dp->common_rates,
                                       intel_dp->num_common_rates, max_rate);
}

/* Theoretical max between source and sink */
static int intel_dp_max_common_rate(struct intel_dp *intel_dp)
{
        return intel_dp->common_rates[intel_dp->num_common_rates - 1];
}

/* Theoretical max between source and sink */
static int intel_dp_max_common_lane_count(struct intel_dp *intel_dp)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        int source_max = intel_dig_port->max_lanes;
        int sink_max = drm_dp_max_lane_count(intel_dp->dpcd);
        int fia_max = intel_tc_port_fia_max_lane_count(intel_dig_port);

        return min3(source_max, sink_max, fia_max);
}

int intel_dp_max_lane_count(struct intel_dp *intel_dp)
{
        return intel_dp->max_link_lane_count;
}

int
intel_dp_link_required(int pixel_clock, int bpp)
{
        /* pixel_clock is in kHz, divide bpp by 8 for bit to Byte conversion */
        return DIV_ROUND_UP(pixel_clock * bpp, 8);
}

int
intel_dp_max_data_rate(int max_link_clock, int max_lanes)
{
        /* max_link_clock is the link symbol clock (LS_Clk) in kHz and not the
         * link rate that is generally expressed in Gbps. Since, 8 bits of data
         * is transmitted every LS_Clk per lane, there is no need to account for
         * the channel encoding that is done in the PHY layer here.
         */

        return max_link_clock * max_lanes;
}

static int
intel_dp_downstream_max_dotclock(struct intel_dp *intel_dp)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct intel_encoder *encoder = &intel_dig_port->base;
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        int max_dotclk = dev_priv->max_dotclk_freq;
        int ds_max_dotclk;

        int type = intel_dp->downstream_ports[0] & DP_DS_PORT_TYPE_MASK;

        if (type != DP_DS_PORT_TYPE_VGA)
                return max_dotclk;

        ds_max_dotclk = drm_dp_downstream_max_clock(intel_dp->dpcd,
                                                    intel_dp->downstream_ports);

        if (ds_max_dotclk != 0)
                max_dotclk = min(max_dotclk, ds_max_dotclk);

        return max_dotclk;
}

static int cnl_max_source_rate(struct intel_dp *intel_dp)
{
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
        enum port port = dig_port->base.port;

        u32 voltage = I915_READ(CNL_PORT_COMP_DW3) & VOLTAGE_INFO_MASK;

        /* Low voltage SKUs are limited to max of 5.4G */
        if (voltage == VOLTAGE_INFO_0_85V)
                return 540000;

        /* For this SKU 8.1G is supported in all ports */
        if (IS_CNL_WITH_PORT_F(dev_priv))
                return 810000;

        /* For other SKUs, max rate on ports A and D is 5.4G */
        if (port == PORT_A || port == PORT_D)
                return 540000;

        return 810000;
}

static int icl_max_source_rate(struct intel_dp *intel_dp)
{
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
        enum phy phy = intel_port_to_phy(dev_priv, dig_port->base.port);

        if (intel_phy_is_combo(dev_priv, phy) &&
            !IS_ELKHARTLAKE(dev_priv) &&
            !intel_dp_is_edp(intel_dp))
                return 540000;

        return 810000;
}

static void
intel_dp_set_source_rates(struct intel_dp *intel_dp)
{
        /* The values must be in increasing order */
        static const int cnl_rates[] = {
                162000, 216000, 270000, 324000, 432000, 540000, 648000, 810000
        };
        static const int bxt_rates[] = {
                162000, 216000, 243000, 270000, 324000, 432000, 540000
        };
        static const int skl_rates[] = {
                162000, 216000, 270000, 324000, 432000, 540000
        };
        static const int hsw_rates[] = {
                162000, 270000, 540000
        };
        static const int g4x_rates[] = {
                162000, 270000
        };
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
        const struct ddi_vbt_port_info *info =
                &dev_priv->vbt.ddi_port_info[dig_port->base.port];
        const int *source_rates;
        int size, max_rate = 0, vbt_max_rate = info->dp_max_link_rate;

        /* This should only be done once */
        WARN_ON(intel_dp->source_rates || intel_dp->num_source_rates);

        if (INTEL_GEN(dev_priv) >= 10) {
                source_rates = cnl_rates;
                size = ARRAY_SIZE(cnl_rates);
                if (IS_GEN(dev_priv, 10))
                        max_rate = cnl_max_source_rate(intel_dp);
                else
                        max_rate = icl_max_source_rate(intel_dp);
        } else if (IS_GEN9_LP(dev_priv)) {
                source_rates = bxt_rates;
                size = ARRAY_SIZE(bxt_rates);
        } else if (IS_GEN9_BC(dev_priv)) {
                source_rates = skl_rates;
                size = ARRAY_SIZE(skl_rates);
        } else if ((IS_HASWELL(dev_priv) && !IS_HSW_ULX(dev_priv)) ||
                   IS_BROADWELL(dev_priv)) {
                source_rates = hsw_rates;
                size = ARRAY_SIZE(hsw_rates);
        } else {
                source_rates = g4x_rates;
                size = ARRAY_SIZE(g4x_rates);
        }

        if (max_rate && vbt_max_rate)
                max_rate = min(max_rate, vbt_max_rate);
        else if (vbt_max_rate)
                max_rate = vbt_max_rate;

        if (max_rate)
                size = intel_dp_rate_limit_len(source_rates, size, max_rate);

        intel_dp->source_rates = source_rates;
        intel_dp->num_source_rates = size;
}

static int intersect_rates(const int *source_rates, int source_len,
                           const int *sink_rates, int sink_len,
                           int *common_rates)
{
        int i = 0, j = 0, k = 0;

        while (i < source_len && j < sink_len) {
                if (source_rates[i] == sink_rates[j]) {
                        if (WARN_ON(k >= DP_MAX_SUPPORTED_RATES))
                                return k;
                        common_rates[k] = source_rates[i];
                        ++k;
                        ++i;
                        ++j;
                } else if (source_rates[i] < sink_rates[j]) {
                        ++i;
                } else {
                        ++j;
                }
        }
        return k;
}

/* return index of rate in rates array, or -1 if not found */
static int intel_dp_rate_index(const int *rates, int len, int rate)
{
        int i;

        for (i = 0; i < len; i++)
                if (rate == rates[i])
                        return i;

        return -1;
}

static void intel_dp_set_common_rates(struct intel_dp *intel_dp)
{
        WARN_ON(!intel_dp->num_source_rates || !intel_dp->num_sink_rates);

        intel_dp->num_common_rates = intersect_rates(intel_dp->source_rates,
                                                     intel_dp->num_source_rates,
                                                     intel_dp->sink_rates,
                                                     intel_dp->num_sink_rates,
                                                     intel_dp->common_rates);

        /* Paranoia, there should always be something in common. */
        if (WARN_ON(intel_dp->num_common_rates == 0)) {
                intel_dp->common_rates[0] = 162000;
                intel_dp->num_common_rates = 1;
        }
}

static bool intel_dp_link_params_valid(struct intel_dp *intel_dp, int link_rate,
                                       u8 lane_count)
{
        /*
         * FIXME: we need to synchronize the current link parameters with
         * hardware readout. Currently fast link training doesn't work on
         * boot-up.
         */
        if (link_rate == 0 ||
            link_rate > intel_dp->max_link_rate)
                return false;

        if (lane_count == 0 ||
            lane_count > intel_dp_max_lane_count(intel_dp))
                return false;

        return true;
}

static bool intel_dp_can_link_train_fallback_for_edp(struct intel_dp *intel_dp,
                                                     int link_rate,
                                                     u8 lane_count)
{
        const struct drm_display_mode *fixed_mode =
                intel_dp->attached_connector->panel.fixed_mode;
        int mode_rate, max_rate;

        mode_rate = intel_dp_link_required(fixed_mode->clock, 18);
        max_rate = intel_dp_max_data_rate(link_rate, lane_count);
        if (mode_rate > max_rate)
                return false;

        return true;
}

int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp,
                                            int link_rate, u8 lane_count)
{
        int index;

        index = intel_dp_rate_index(intel_dp->common_rates,
                                    intel_dp->num_common_rates,
                                    link_rate);
        if (index > 0) {
                if (intel_dp_is_edp(intel_dp) &&
                    !intel_dp_can_link_train_fallback_for_edp(intel_dp,
                                                              intel_dp->common_rates[index - 1],
                                                              lane_count)) {
                        DRM_DEBUG_KMS("Retrying Link training for eDP with same parameters\n");
                        return 0;
                }
                intel_dp->max_link_rate = intel_dp->common_rates[index - 1];
                intel_dp->max_link_lane_count = lane_count;
        } else if (lane_count > 1) {
                if (intel_dp_is_edp(intel_dp) &&
                    !intel_dp_can_link_train_fallback_for_edp(intel_dp,
                                                              intel_dp_max_common_rate(intel_dp),
                                                              lane_count >> 1)) {
                        DRM_DEBUG_KMS("Retrying Link training for eDP with same parameters\n");
                        return 0;
                }
                intel_dp->max_link_rate = intel_dp_max_common_rate(intel_dp);
                intel_dp->max_link_lane_count = lane_count >> 1;
        } else {
                DRM_ERROR("Link Training Unsuccessful\n");
                return -1;
        }

        return 0;
}

u32 intel_dp_mode_to_fec_clock(u32 mode_clock)
{
        return div_u64(mul_u32_u32(mode_clock, 1000000U),
                       DP_DSC_FEC_OVERHEAD_FACTOR);
}

static int
small_joiner_ram_size_bits(struct drm_i915_private *i915)
{
        if (INTEL_GEN(i915) >= 11)
                return 7680 * 8;
        else
                return 6144 * 8;
}

static u16 intel_dp_dsc_get_output_bpp(struct drm_i915_private *i915,
                                       u32 link_clock, u32 lane_count,
                                       u32 mode_clock, u32 mode_hdisplay)
{
        u32 bits_per_pixel, max_bpp_small_joiner_ram;
        int i;

        /*
         * Available Link Bandwidth(Kbits/sec) = (NumberOfLanes)*
         * (LinkSymbolClock)* 8 * (TimeSlotsPerMTP)
         * for SST -> TimeSlotsPerMTP is 1,
         * for MST -> TimeSlotsPerMTP has to be calculated
         */
        bits_per_pixel = (link_clock * lane_count * 8) /
                         intel_dp_mode_to_fec_clock(mode_clock);
        DRM_DEBUG_KMS("Max link bpp: %u\n", bits_per_pixel);

        /* Small Joiner Check: output bpp <= joiner RAM (bits) / Horiz. width */
        max_bpp_small_joiner_ram = small_joiner_ram_size_bits(i915) /
                mode_hdisplay;
        DRM_DEBUG_KMS("Max small joiner bpp: %u\n", max_bpp_small_joiner_ram);

        /*
         * Greatest allowed DSC BPP = MIN (output BPP from available Link BW
         * check, output bpp from small joiner RAM check)
         */
        bits_per_pixel = min(bits_per_pixel, max_bpp_small_joiner_ram);

        /* Error out if the max bpp is less than smallest allowed valid bpp */
        if (bits_per_pixel < valid_dsc_bpp[0]) {
                DRM_DEBUG_KMS("Unsupported BPP %u, min %u\n",
                              bits_per_pixel, valid_dsc_bpp[0]);
                return 0;
        }

        /* Find the nearest match in the array of known BPPs from VESA */
        for (i = 0; i < ARRAY_SIZE(valid_dsc_bpp) - 1; i++) {
                if (bits_per_pixel < valid_dsc_bpp[i + 1])
                        break;
        }
        bits_per_pixel = valid_dsc_bpp[i];

        /*
         * Compressed BPP in U6.4 format so multiply by 16, for Gen 11,
         * fractional part is 0
         */
        return bits_per_pixel << 4;
}

static u8 intel_dp_dsc_get_slice_count(struct intel_dp *intel_dp,
                                       int mode_clock, int mode_hdisplay)
{
        u8 min_slice_count, i;
        int max_slice_width;

        if (mode_clock <= DP_DSC_PEAK_PIXEL_RATE)
                min_slice_count = DIV_ROUND_UP(mode_clock,
                                               DP_DSC_MAX_ENC_THROUGHPUT_0);
        else
                min_slice_count = DIV_ROUND_UP(mode_clock,
                                               DP_DSC_MAX_ENC_THROUGHPUT_1);

        max_slice_width = drm_dp_dsc_sink_max_slice_width(intel_dp->dsc_dpcd);
        if (max_slice_width < DP_DSC_MIN_SLICE_WIDTH_VALUE) {
                DRM_DEBUG_KMS("Unsupported slice width %d by DP DSC Sink device\n",
                              max_slice_width);
                return 0;
        }
        /* Also take into account max slice width */
        min_slice_count = min_t(u8, min_slice_count,
                                DIV_ROUND_UP(mode_hdisplay,
                                             max_slice_width));

        /* Find the closest match to the valid slice count values */
        for (i = 0; i < ARRAY_SIZE(valid_dsc_slicecount); i++) {
                if (valid_dsc_slicecount[i] >
                    drm_dp_dsc_sink_max_slice_count(intel_dp->dsc_dpcd,
                                                    false))
                        break;
                if (min_slice_count  <= valid_dsc_slicecount[i])
                        return valid_dsc_slicecount[i];
        }

        DRM_DEBUG_KMS("Unsupported Slice Count %d\n", min_slice_count);
        return 0;
}

static bool intel_dp_hdisplay_bad(struct drm_i915_private *dev_priv,
                                  int hdisplay)
{
        /*
         * Older platforms don't like hdisplay==4096 with DP.
         *
         * On ILK/SNB/IVB the pipe seems to be somewhat running (scanline
         * and frame counter increment), but we don't get vblank interrupts,
         * and the pipe underruns immediately. The link also doesn't seem
         * to get trained properly.
         *
         * On CHV the vblank interrupts don't seem to disappear but
         * otherwise the symptoms are similar.
         *
         * TODO: confirm the behaviour on HSW+
         */
        return hdisplay == 4096 && !HAS_DDI(dev_priv);
}

static enum drm_mode_status
intel_dp_mode_valid(struct drm_connector *connector,
                    struct drm_display_mode *mode)
{
        struct intel_dp *intel_dp = intel_attached_dp(connector);
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct drm_display_mode *fixed_mode = intel_connector->panel.fixed_mode;
        struct drm_i915_private *dev_priv = to_i915(connector->dev);
        int target_clock = mode->clock;
        int max_rate, mode_rate, max_lanes, max_link_clock;
        int max_dotclk;
        u16 dsc_max_output_bpp = 0;
        u8 dsc_slice_count = 0;

        if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return MODE_NO_DBLESCAN;

        max_dotclk = intel_dp_downstream_max_dotclock(intel_dp);

        if (intel_dp_is_edp(intel_dp) && fixed_mode) {
                if (mode->hdisplay > fixed_mode->hdisplay)
                        return MODE_PANEL;

                if (mode->vdisplay > fixed_mode->vdisplay)
                        return MODE_PANEL;

                target_clock = fixed_mode->clock;
        }

        max_link_clock = intel_dp_max_link_rate(intel_dp);
        max_lanes = intel_dp_max_lane_count(intel_dp);

        max_rate = intel_dp_max_data_rate(max_link_clock, max_lanes);
        mode_rate = intel_dp_link_required(target_clock, 18);

        if (intel_dp_hdisplay_bad(dev_priv, mode->hdisplay))
                return MODE_H_ILLEGAL;

        /*
         * Output bpp is stored in 6.4 format so right shift by 4 to get the
         * integer value since we support only integer values of bpp.
         */
        if ((INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) &&
            drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd)) {
                if (intel_dp_is_edp(intel_dp)) {
                        dsc_max_output_bpp =
                                drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd) >> 4;
                        dsc_slice_count =
                                drm_dp_dsc_sink_max_slice_count(intel_dp->dsc_dpcd,
                                                                true);
                } else if (drm_dp_sink_supports_fec(intel_dp->fec_capable)) {
                        dsc_max_output_bpp =
                                intel_dp_dsc_get_output_bpp(dev_priv,
                                                            max_link_clock,
                                                            max_lanes,
                                                            target_clock,
                                                            mode->hdisplay) >> 4;
                        dsc_slice_count =
                                intel_dp_dsc_get_slice_count(intel_dp,
                                                             target_clock,
                                                             mode->hdisplay);
                }
        }

        if ((mode_rate > max_rate && !(dsc_max_output_bpp && dsc_slice_count)) ||
            target_clock > max_dotclk)
                return MODE_CLOCK_HIGH;

        if (mode->clock < 10000)
                return MODE_CLOCK_LOW;

        if (mode->flags & DRM_MODE_FLAG_DBLCLK)
                return MODE_H_ILLEGAL;

        return intel_mode_valid_max_plane_size(dev_priv, mode);
}

u32 intel_dp_pack_aux(const u8 *src, int src_bytes)
{
        int i;
        u32 v = 0;

        if (src_bytes > 4)
                src_bytes = 4;
        for (i = 0; i < src_bytes; i++)
                v |= ((u32)src[i]) << ((3 - i) * 8);
        return v;
}

static void intel_dp_unpack_aux(u32 src, u8 *dst, int dst_bytes)
{
        int i;
        if (dst_bytes > 4)
                dst_bytes = 4;
        for (i = 0; i < dst_bytes; i++)
                dst[i] = src >> ((3-i) * 8);
}

static void
intel_dp_init_panel_power_sequencer(struct intel_dp *intel_dp);
static void
intel_dp_init_panel_power_sequencer_registers(struct intel_dp *intel_dp,
                                              bool force_disable_vdd);
static void
intel_dp_pps_init(struct intel_dp *intel_dp);

static intel_wakeref_t
pps_lock(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        intel_wakeref_t wakeref;

        /*
         * See intel_power_sequencer_reset() why we need
         * a power domain reference here.
         */
        wakeref = intel_display_power_get(dev_priv,
                                          intel_aux_power_domain(dp_to_dig_port(intel_dp)));

        mutex_lock(&dev_priv->pps_mutex);

        return wakeref;
}

static intel_wakeref_t
pps_unlock(struct intel_dp *intel_dp, intel_wakeref_t wakeref)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        mutex_unlock(&dev_priv->pps_mutex);
        intel_display_power_put(dev_priv,
                                intel_aux_power_domain(dp_to_dig_port(intel_dp)),
                                wakeref);
        return 0;
}

#define with_pps_lock(dp, wf) \
        for ((wf) = pps_lock(dp); (wf); (wf) = pps_unlock((dp), (wf)))

static void
vlv_power_sequencer_kick(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        enum pipe pipe = intel_dp->pps_pipe;
        bool pll_enabled, release_cl_override = false;
        enum dpio_phy phy = DPIO_PHY(pipe);
        enum dpio_channel ch = vlv_pipe_to_channel(pipe);
        u32 DP;

        if (WARN(I915_READ(intel_dp->output_reg) & DP_PORT_EN,
                 "skipping pipe %c power sequencer kick due to [ENCODER:%d:%s] being active\n",
                 pipe_name(pipe), intel_dig_port->base.base.base.id,
                 intel_dig_port->base.base.name))
                return;

        DRM_DEBUG_KMS("kicking pipe %c power sequencer for [ENCODER:%d:%s]\n",
                      pipe_name(pipe), intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name);

        /* Preserve the BIOS-computed detected bit. This is
         * supposed to be read-only.
         */
        DP = I915_READ(intel_dp->output_reg) & DP_DETECTED;
        DP |= DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0;
        DP |= DP_PORT_WIDTH(1);
        DP |= DP_LINK_TRAIN_PAT_1;

        if (IS_CHERRYVIEW(dev_priv))
                DP |= DP_PIPE_SEL_CHV(pipe);
        else
                DP |= DP_PIPE_SEL(pipe);

        pll_enabled = I915_READ(DPLL(pipe)) & DPLL_VCO_ENABLE;

        /*
         * The DPLL for the pipe must be enabled for this to work.
         * So enable temporarily it if it's not already enabled.
         */
        if (!pll_enabled) {
                release_cl_override = IS_CHERRYVIEW(dev_priv) &&
                        !chv_phy_powergate_ch(dev_priv, phy, ch, true);

                if (vlv_force_pll_on(dev_priv, pipe, IS_CHERRYVIEW(dev_priv) ?
                                     &chv_dpll[0].dpll : &vlv_dpll[0].dpll)) {
                        DRM_ERROR("Failed to force on pll for pipe %c!\n",
                                  pipe_name(pipe));
                        return;
                }
        }

        /*
         * Similar magic as in intel_dp_enable_port().
         * We _must_ do this port enable + disable trick
         * to make this power sequencer lock onto the port.
         * Otherwise even VDD force bit won't work.
         */
        I915_WRITE(intel_dp->output_reg, DP);
        POSTING_READ(intel_dp->output_reg);

        I915_WRITE(intel_dp->output_reg, DP | DP_PORT_EN);
        POSTING_READ(intel_dp->output_reg);

        I915_WRITE(intel_dp->output_reg, DP & ~DP_PORT_EN);
        POSTING_READ(intel_dp->output_reg);

        if (!pll_enabled) {
                vlv_force_pll_off(dev_priv, pipe);

                if (release_cl_override)
                        chv_phy_powergate_ch(dev_priv, phy, ch, false);
        }
}

static enum pipe vlv_find_free_pps(struct drm_i915_private *dev_priv)
{
        struct intel_encoder *encoder;
        unsigned int pipes = (1 << PIPE_A) | (1 << PIPE_B);

        /*
         * We don't have power sequencer currently.
         * Pick one that's not used by other ports.
         */
        for_each_intel_dp(&dev_priv->drm, encoder) {
                struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);

                if (encoder->type == INTEL_OUTPUT_EDP) {
                        WARN_ON(intel_dp->active_pipe != INVALID_PIPE &&
                                intel_dp->active_pipe != intel_dp->pps_pipe);

                        if (intel_dp->pps_pipe != INVALID_PIPE)
                                pipes &= ~(1 << intel_dp->pps_pipe);
                } else {
                        WARN_ON(intel_dp->pps_pipe != INVALID_PIPE);

                        if (intel_dp->active_pipe != INVALID_PIPE)
                                pipes &= ~(1 << intel_dp->active_pipe);
                }
        }

        if (pipes == 0)
                return INVALID_PIPE;

        return ffs(pipes) - 1;
}

static enum pipe
vlv_power_sequencer_pipe(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        enum pipe pipe;

        lockdep_assert_held(&dev_priv->pps_mutex);

        /* We should never land here with regular DP ports */
        WARN_ON(!intel_dp_is_edp(intel_dp));

        WARN_ON(intel_dp->active_pipe != INVALID_PIPE &&
                intel_dp->active_pipe != intel_dp->pps_pipe);

        if (intel_dp->pps_pipe != INVALID_PIPE)
                return intel_dp->pps_pipe;

        pipe = vlv_find_free_pps(dev_priv);

        /*
         * Didn't find one. This should not happen since there
         * are two power sequencers and up to two eDP ports.
         */
        if (WARN_ON(pipe == INVALID_PIPE))
                pipe = PIPE_A;

        vlv_steal_power_sequencer(dev_priv, pipe);
        intel_dp->pps_pipe = pipe;

        DRM_DEBUG_KMS("picked pipe %c power sequencer for [ENCODER:%d:%s]\n",
                      pipe_name(intel_dp->pps_pipe),
                      intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name);

        /* init power sequencer on this pipe and port */
        intel_dp_init_panel_power_sequencer(intel_dp);
        intel_dp_init_panel_power_sequencer_registers(intel_dp, true);

        /*
         * Even vdd force doesn't work until we've made
         * the power sequencer lock in on the port.
         */
        vlv_power_sequencer_kick(intel_dp);

        return intel_dp->pps_pipe;
}

static int
bxt_power_sequencer_idx(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        int backlight_controller = dev_priv->vbt.backlight.controller;

        lockdep_assert_held(&dev_priv->pps_mutex);

        /* We should never land here with regular DP ports */
        WARN_ON(!intel_dp_is_edp(intel_dp));

        if (!intel_dp->pps_reset)
                return backlight_controller;

        intel_dp->pps_reset = false;

        /*
         * Only the HW needs to be reprogrammed, the SW state is fixed and
         * has been setup during connector init.
         */
        intel_dp_init_panel_power_sequencer_registers(intel_dp, false);

        return backlight_controller;
}

typedef bool (*vlv_pipe_check)(struct drm_i915_private *dev_priv,
                               enum pipe pipe);

static bool vlv_pipe_has_pp_on(struct drm_i915_private *dev_priv,
                               enum pipe pipe)
{
        return I915_READ(PP_STATUS(pipe)) & PP_ON;
}

static bool vlv_pipe_has_vdd_on(struct drm_i915_private *dev_priv,
                                enum pipe pipe)
{
        return I915_READ(PP_CONTROL(pipe)) & EDP_FORCE_VDD;
}

static bool vlv_pipe_any(struct drm_i915_private *dev_priv,
                         enum pipe pipe)
{
        return true;
}

static enum pipe
vlv_initial_pps_pipe(struct drm_i915_private *dev_priv,
                     enum port port,
                     vlv_pipe_check pipe_check)
{
        enum pipe pipe;

        for (pipe = PIPE_A; pipe <= PIPE_B; pipe++) {
                u32 port_sel = I915_READ(PP_ON_DELAYS(pipe)) &
                        PANEL_PORT_SELECT_MASK;

                if (port_sel != PANEL_PORT_SELECT_VLV(port))
                        continue;

                if (!pipe_check(dev_priv, pipe))
                        continue;

                return pipe;
        }

        return INVALID_PIPE;
}

static void
vlv_initial_power_sequencer_setup(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        enum port port = intel_dig_port->base.port;

        lockdep_assert_held(&dev_priv->pps_mutex);

        /* try to find a pipe with this port selected */
        /* first pick one where the panel is on */
        intel_dp->pps_pipe = vlv_initial_pps_pipe(dev_priv, port,
                                                  vlv_pipe_has_pp_on);
        /* didn't find one? pick one where vdd is on */
        if (intel_dp->pps_pipe == INVALID_PIPE)
                intel_dp->pps_pipe = vlv_initial_pps_pipe(dev_priv, port,
                                                          vlv_pipe_has_vdd_on);
        /* didn't find one? pick one with just the correct port */
        if (intel_dp->pps_pipe == INVALID_PIPE)
                intel_dp->pps_pipe = vlv_initial_pps_pipe(dev_priv, port,
                                                          vlv_pipe_any);

        /* didn't find one? just let vlv_power_sequencer_pipe() pick one when needed */
        if (intel_dp->pps_pipe == INVALID_PIPE) {
                DRM_DEBUG_KMS("no initial power sequencer for [ENCODER:%d:%s]\n",
                              intel_dig_port->base.base.base.id,
                              intel_dig_port->base.base.name);
                return;
        }

        DRM_DEBUG_KMS("initial power sequencer for [ENCODER:%d:%s]: pipe %c\n",
                      intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name,
                      pipe_name(intel_dp->pps_pipe));

        intel_dp_init_panel_power_sequencer(intel_dp);
        intel_dp_init_panel_power_sequencer_registers(intel_dp, false);
}

void intel_power_sequencer_reset(struct drm_i915_private *dev_priv)
{
        struct intel_encoder *encoder;

        if (WARN_ON(!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv) &&
                    !IS_GEN9_LP(dev_priv)))
                return;

        /*
         * We can't grab pps_mutex here due to deadlock with power_domain
         * mutex when power_domain functions are called while holding pps_mutex.
         * That also means that in order to use pps_pipe the code needs to
         * hold both a power domain reference and pps_mutex, and the power domain
         * reference get/put must be done while _not_ holding pps_mutex.
         * pps_{lock,unlock}() do these steps in the correct order, so one
         * should use them always.
         */

        for_each_intel_dp(&dev_priv->drm, encoder) {
                struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);

                WARN_ON(intel_dp->active_pipe != INVALID_PIPE);

                if (encoder->type != INTEL_OUTPUT_EDP)
                        continue;

                if (IS_GEN9_LP(dev_priv))
                        intel_dp->pps_reset = true;
                else
                        intel_dp->pps_pipe = INVALID_PIPE;
        }
}

struct pps_registers {
        i915_reg_t pp_ctrl;
        i915_reg_t pp_stat;
        i915_reg_t pp_on;
        i915_reg_t pp_off;
        i915_reg_t pp_div;
};

static void intel_pps_get_registers(struct intel_dp *intel_dp,
                                    struct pps_registers *regs)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        int pps_idx = 0;

        memset(regs, 0, sizeof(*regs));

        if (IS_GEN9_LP(dev_priv))
                pps_idx = bxt_power_sequencer_idx(intel_dp);
        else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                pps_idx = vlv_power_sequencer_pipe(intel_dp);

        regs->pp_ctrl = PP_CONTROL(pps_idx);
        regs->pp_stat = PP_STATUS(pps_idx);
        regs->pp_on = PP_ON_DELAYS(pps_idx);
        regs->pp_off = PP_OFF_DELAYS(pps_idx);

        /* Cycle delay moved from PP_DIVISOR to PP_CONTROL */
        if (IS_GEN9_LP(dev_priv) || INTEL_PCH_TYPE(dev_priv) >= PCH_CNP)
                regs->pp_div = INVALID_MMIO_REG;
        else
                regs->pp_div = PP_DIVISOR(pps_idx);
}

static i915_reg_t
_pp_ctrl_reg(struct intel_dp *intel_dp)
{
        struct pps_registers regs;

        intel_pps_get_registers(intel_dp, &regs);

        return regs.pp_ctrl;
}

static i915_reg_t
_pp_stat_reg(struct intel_dp *intel_dp)
{
        struct pps_registers regs;

        intel_pps_get_registers(intel_dp, &regs);

        return regs.pp_stat;
}

/* Reboot notifier handler to shutdown panel power to guarantee T12 timing
   This function only applicable when panel PM state is not to be tracked */
static int edp_notify_handler(struct notifier_block *this, unsigned long code,
                              void *unused)
{
        struct intel_dp *intel_dp = container_of(this, typeof(* intel_dp),
                                                 edp_notifier);
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        intel_wakeref_t wakeref;

        if (!intel_dp_is_edp(intel_dp) || code != SYS_RESTART)
                return 0;

        with_pps_lock(intel_dp, wakeref) {
                if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                        enum pipe pipe = vlv_power_sequencer_pipe(intel_dp);
                        i915_reg_t pp_ctrl_reg, pp_div_reg;
                        u32 pp_div;

                        pp_ctrl_reg = PP_CONTROL(pipe);
                        pp_div_reg  = PP_DIVISOR(pipe);
                        pp_div = I915_READ(pp_div_reg);
                        pp_div &= PP_REFERENCE_DIVIDER_MASK;

                        /* 0x1F write to PP_DIV_REG sets max cycle delay */
                        I915_WRITE(pp_div_reg, pp_div | 0x1F);
                        I915_WRITE(pp_ctrl_reg, PANEL_UNLOCK_REGS);
                        msleep(intel_dp->panel_power_cycle_delay);
                }
        }

        return 0;
}

static bool edp_have_panel_power(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        lockdep_assert_held(&dev_priv->pps_mutex);

        if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
            intel_dp->pps_pipe == INVALID_PIPE)
                return false;

        return (I915_READ(_pp_stat_reg(intel_dp)) & PP_ON) != 0;
}

static bool edp_have_panel_vdd(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        lockdep_assert_held(&dev_priv->pps_mutex);

        if ((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
            intel_dp->pps_pipe == INVALID_PIPE)
                return false;

        return I915_READ(_pp_ctrl_reg(intel_dp)) & EDP_FORCE_VDD;
}

static void
intel_dp_check_edp(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        if (!intel_dp_is_edp(intel_dp))
                return;

        if (!edp_have_panel_power(intel_dp) && !edp_have_panel_vdd(intel_dp)) {
                WARN(1, "eDP powered off while attempting aux channel communication.\n");
                DRM_DEBUG_KMS("Status 0x%08x Control 0x%08x\n",
                              I915_READ(_pp_stat_reg(intel_dp)),
                              I915_READ(_pp_ctrl_reg(intel_dp)));
        }
}

static u32
intel_dp_aux_wait_done(struct intel_dp *intel_dp)
{
        struct drm_i915_private *i915 = dp_to_i915(intel_dp);
        i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
        const unsigned int timeout_ms = 10;
        u32 status;
        bool done;

#define C (((status = intel_uncore_read_notrace(&i915->uncore, ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
        done = wait_event_timeout(i915->gmbus_wait_queue, C,
                                  msecs_to_jiffies_timeout(timeout_ms));

        /* just trace the final value */
        trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);

        if (!done)
                DRM_ERROR("%s did not complete or timeout within %ums (status 0x%08x)\n",
                          intel_dp->aux.name, timeout_ms, status);
#undef C

        return status;
}

static u32 g4x_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        if (index)
                return 0;

        /*
         * The clock divider is based off the hrawclk, and would like to run at
         * 2MHz.  So, take the hrawclk value and divide by 2000 and use that
         */
        return DIV_ROUND_CLOSEST(dev_priv->rawclk_freq, 2000);
}

static u32 ilk_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);

        if (index)
                return 0;

        /*
         * The clock divider is based off the cdclk or PCH rawclk, and would
         * like to run at 2MHz.  So, take the cdclk or PCH rawclk value and
         * divide by 2000 and use that
         */
        if (dig_port->aux_ch == AUX_CH_A)
                return DIV_ROUND_CLOSEST(dev_priv->cdclk.hw.cdclk, 2000);
        else
                return DIV_ROUND_CLOSEST(dev_priv->rawclk_freq, 2000);
}

static u32 hsw_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);

        if (dig_port->aux_ch != AUX_CH_A && HAS_PCH_LPT_H(dev_priv)) {
                /* Workaround for non-ULT HSW */
                switch (index) {
                case 0: return 63;
                case 1: return 72;
                default: return 0;
                }
        }

        return ilk_get_aux_clock_divider(intel_dp, index);
}

static u32 skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
{
        /*
         * SKL doesn't need us to program the AUX clock divider (Hardware will
         * derive the clock from CDCLK automatically). We still implement the
         * get_aux_clock_divider vfunc to plug-in into the existing code.
         */
        return index ? 0 : 1;
}

static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
                                int send_bytes,
                                u32 aux_clock_divider)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv =
                        to_i915(intel_dig_port->base.base.dev);
        u32 precharge, timeout;

        if (IS_GEN(dev_priv, 6))
                precharge = 3;
        else
                precharge = 5;

        if (IS_BROADWELL(dev_priv))
                timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
        else
                timeout = DP_AUX_CH_CTL_TIME_OUT_400us;

        return DP_AUX_CH_CTL_SEND_BUSY |
               DP_AUX_CH_CTL_DONE |
               DP_AUX_CH_CTL_INTERRUPT |
               DP_AUX_CH_CTL_TIME_OUT_ERROR |
               timeout |
               DP_AUX_CH_CTL_RECEIVE_ERROR |
               (send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
               (precharge << DP_AUX_CH_CTL_PRECHARGE_2US_SHIFT) |
               (aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT);
}

static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
                                int send_bytes,
                                u32 unused)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *i915 =
                        to_i915(intel_dig_port->base.base.dev);
        enum phy phy = intel_port_to_phy(i915, intel_dig_port->base.port);
        u32 ret;

        ret = DP_AUX_CH_CTL_SEND_BUSY |
              DP_AUX_CH_CTL_DONE |
              DP_AUX_CH_CTL_INTERRUPT |
              DP_AUX_CH_CTL_TIME_OUT_ERROR |
              DP_AUX_CH_CTL_TIME_OUT_MAX |
              DP_AUX_CH_CTL_RECEIVE_ERROR |
              (send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
              DP_AUX_CH_CTL_FW_SYNC_PULSE_SKL(32) |
              DP_AUX_CH_CTL_SYNC_PULSE_SKL(32);

        if (intel_phy_is_tc(i915, phy) &&
            intel_dig_port->tc_mode == TC_PORT_TBT_ALT)
                ret |= DP_AUX_CH_CTL_TBT_IO;

        return ret;
}

static int
intel_dp_aux_xfer(struct intel_dp *intel_dp,
                  const u8 *send, int send_bytes,
                  u8 *recv, int recv_size,
                  u32 aux_send_ctl_flags)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *i915 =
                        to_i915(intel_dig_port->base.base.dev);
        struct intel_uncore *uncore = &i915->uncore;
        enum phy phy = intel_port_to_phy(i915, intel_dig_port->base.port);
        bool is_tc_port = intel_phy_is_tc(i915, phy);
        i915_reg_t ch_ctl, ch_data[5];
        u32 aux_clock_divider;
        enum intel_display_power_domain aux_domain =
                intel_aux_power_domain(intel_dig_port);
        intel_wakeref_t aux_wakeref;
        intel_wakeref_t pps_wakeref;
        int i, ret, recv_bytes;
        int try, clock = 0;
        u32 status;
        bool vdd;

        ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
        for (i = 0; i < ARRAY_SIZE(ch_data); i++)
                ch_data[i] = intel_dp->aux_ch_data_reg(intel_dp, i);

        if (is_tc_port)
                intel_tc_port_lock(intel_dig_port);

        aux_wakeref = intel_display_power_get(i915, aux_domain);
        pps_wakeref = pps_lock(intel_dp);

        /*
         * We will be called with VDD already enabled for dpcd/edid/oui reads.
         * In such cases we want to leave VDD enabled and it's up to upper layers
         * to turn it off. But for eg. i2c-dev access we need to turn it on/off
         * ourselves.
         */
        vdd = edp_panel_vdd_on(intel_dp);

        /* dp aux is extremely sensitive to irq latency, hence request the
         * lowest possible wakeup latency and so prevent the cpu from going into
         * deep sleep states.
         */
        pm_qos_update_request(&i915->pm_qos, 0);

        intel_dp_check_edp(intel_dp);

        /* Try to wait for any previous AUX channel activity */
        for (try = 0; try < 3; try++) {
                status = intel_uncore_read_notrace(uncore, ch_ctl);
                if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
                        break;
                msleep(1);
        }
        /* just trace the final value */
        trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);

        if (try == 3) {
                const u32 status = intel_uncore_read(uncore, ch_ctl);

                if (status != intel_dp->aux_busy_last_status) {
                        WARN(1, "dp_aux_ch not started status 0x%08x\n",
                             status);
                        intel_dp->aux_busy_last_status = status;
                }

                ret = -EBUSY;
                goto out;
        }

        /* Only 5 data registers! */
        if (WARN_ON(send_bytes > 20 || recv_size > 20)) {
                ret = -E2BIG;
                goto out;
        }

        while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
                u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
                                                          send_bytes,
                                                          aux_clock_divider);

                send_ctl |= aux_send_ctl_flags;

                /* Must try at least 3 times according to DP spec */
                for (try = 0; try < 5; try++) {
                        /* Load the send data into the aux channel data registers */
                        for (i = 0; i < send_bytes; i += 4)
                                intel_uncore_write(uncore,
                                                   ch_data[i >> 2],
                                                   intel_dp_pack_aux(send + i,
                                                                     send_bytes - i));

                        /* Send the command and wait for it to complete */
                        intel_uncore_write(uncore, ch_ctl, send_ctl);

                        status = intel_dp_aux_wait_done(intel_dp);

                        /* Clear done status and any errors */
                        intel_uncore_write(uncore,
                                           ch_ctl,
                                           status |
                                           DP_AUX_CH_CTL_DONE |
                                           DP_AUX_CH_CTL_TIME_OUT_ERROR |
                                           DP_AUX_CH_CTL_RECEIVE_ERROR);

                        /* DP CTS 1.2 Core Rev 1.1, 4.2.1.1 & 4.2.1.2
                         *   400us delay required for errors and timeouts
                         *   Timeout errors from the HW already meet this
                         *   requirement so skip to next iteration
                         */
                        if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR)
                                continue;

                        if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
                                usleep_range(400, 500);
                                continue;
                        }
                        if (status & DP_AUX_CH_CTL_DONE)
                                goto done;
                }
        }

        if ((status & DP_AUX_CH_CTL_DONE) == 0) {
                DRM_ERROR("dp_aux_ch not done status 0x%08x\n", status);
                ret = -EBUSY;
                goto out;
        }

done:
        /* Check for timeout or receive error.
         * Timeouts occur when the sink is not connected
         */
        if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
                DRM_ERROR("dp_aux_ch receive error status 0x%08x\n", status);
                ret = -EIO;
                goto out;
        }

        /* Timeouts occur when the device isn't connected, so they're
         * "normal" -- don't fill the kernel log with these */
        if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
                DRM_DEBUG_KMS("dp_aux_ch timeout status 0x%08x\n", status);
                ret = -ETIMEDOUT;
                goto out;
        }

        /* Unload any bytes sent back from the other side */
        recv_bytes = ((status & DP_AUX_CH_CTL_MESSAGE_SIZE_MASK) >>
                      DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT);

        /*
         * By BSpec: "Message sizes of 0 or >20 are not allowed."
         * We have no idea of what happened so we return -EBUSY so
         * drm layer takes care for the necessary retries.
         */
        if (recv_bytes == 0 || recv_bytes > 20) {
                DRM_DEBUG_KMS("Forbidden recv_bytes = %d on aux transaction\n",
                              recv_bytes);
                ret = -EBUSY;
                goto out;
        }

        if (recv_bytes > recv_size)
                recv_bytes = recv_size;

        for (i = 0; i < recv_bytes; i += 4)
                intel_dp_unpack_aux(intel_uncore_read(uncore, ch_data[i >> 2]),
                                    recv + i, recv_bytes - i);

        ret = recv_bytes;
out:
        pm_qos_update_request(&i915->pm_qos, PM_QOS_DEFAULT_VALUE);

        if (vdd)
                edp_panel_vdd_off(intel_dp, false);

        pps_unlock(intel_dp, pps_wakeref);
        intel_display_power_put_async(i915, aux_domain, aux_wakeref);

        if (is_tc_port)
                intel_tc_port_unlock(intel_dig_port);

        return ret;
}

#define BARE_ADDRESS_SIZE       3
#define HEADER_SIZE             (BARE_ADDRESS_SIZE + 1)

static void
intel_dp_aux_header(u8 txbuf[HEADER_SIZE],
                    const struct drm_dp_aux_msg *msg)
{
        txbuf[0] = (msg->request << 4) | ((msg->address >> 16) & 0xf);
        txbuf[1] = (msg->address >> 8) & 0xff;
        txbuf[2] = msg->address & 0xff;
        txbuf[3] = msg->size - 1;
}

static ssize_t
intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
{
        struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux);
        u8 txbuf[20], rxbuf[20];
        size_t txsize, rxsize;
        int ret;

        intel_dp_aux_header(txbuf, msg);

        switch (msg->request & ~DP_AUX_I2C_MOT) {
        case DP_AUX_NATIVE_WRITE:
        case DP_AUX_I2C_WRITE:
        case DP_AUX_I2C_WRITE_STATUS_UPDATE:
                txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
                rxsize = 2; /* 0 or 1 data bytes */

                if (WARN_ON(txsize > 20))
                        return -E2BIG;

                WARN_ON(!msg->buffer != !msg->size);

                if (msg->buffer)
                        memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);

                ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
                                        rxbuf, rxsize, 0);
                if (ret > 0) {
                        msg->reply = rxbuf[0] >> 4;

                        if (ret > 1) {
                                /* Number of bytes written in a short write. */
                                ret = clamp_t(int, rxbuf[1], 0, msg->size);
                        } else {
                                /* Return payload size. */
                                ret = msg->size;
                        }
                }
                break;

        case DP_AUX_NATIVE_READ:
        case DP_AUX_I2C_READ:
                txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
                rxsize = msg->size + 1;

                if (WARN_ON(rxsize > 20))
                        return -E2BIG;

                ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
                                        rxbuf, rxsize, 0);
                if (ret > 0) {
                        msg->reply = rxbuf[0] >> 4;
                        /*
                         * Assume happy day, and copy the data. The caller is
                         * expected to check msg->reply before touching it.
                         *
                         * Return payload size.
                         */
                        ret--;
                        memcpy(msg->buffer, rxbuf + 1, ret);
                }
                break;

        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}


static i915_reg_t g4x_aux_ctl_reg(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        enum aux_ch aux_ch = dig_port->aux_ch;

        switch (aux_ch) {
        case AUX_CH_B:
        case AUX_CH_C:
        case AUX_CH_D:
                return DP_AUX_CH_CTL(aux_ch);
        default:
                MISSING_CASE(aux_ch);
                return DP_AUX_CH_CTL(AUX_CH_B);
        }
}

static i915_reg_t g4x_aux_data_reg(struct intel_dp *intel_dp, int index)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        enum aux_ch aux_ch = dig_port->aux_ch;

        switch (aux_ch) {
        case AUX_CH_B:
        case AUX_CH_C:
        case AUX_CH_D:
                return DP_AUX_CH_DATA(aux_ch, index);
        default:
                MISSING_CASE(aux_ch);
                return DP_AUX_CH_DATA(AUX_CH_B, index);
        }
}

static i915_reg_t ilk_aux_ctl_reg(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        enum aux_ch aux_ch = dig_port->aux_ch;

        switch (aux_ch) {
        case AUX_CH_A:
                return DP_AUX_CH_CTL(aux_ch);
        case AUX_CH_B:
        case AUX_CH_C:
        case AUX_CH_D:
                return PCH_DP_AUX_CH_CTL(aux_ch);
        default:
                MISSING_CASE(aux_ch);
                return DP_AUX_CH_CTL(AUX_CH_A);
        }
}

static i915_reg_t ilk_aux_data_reg(struct intel_dp *intel_dp, int index)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        enum aux_ch aux_ch = dig_port->aux_ch;

        switch (aux_ch) {
        case AUX_CH_A:
                return DP_AUX_CH_DATA(aux_ch, index);
        case AUX_CH_B:
        case AUX_CH_C:
        case AUX_CH_D:
                return PCH_DP_AUX_CH_DATA(aux_ch, index);
        default:
                MISSING_CASE(aux_ch);
                return DP_AUX_CH_DATA(AUX_CH_A, index);
        }
}

static i915_reg_t skl_aux_ctl_reg(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        enum aux_ch aux_ch = dig_port->aux_ch;

        switch (aux_ch) {
        case AUX_CH_A:
        case AUX_CH_B:
        case AUX_CH_C:
        case AUX_CH_D:
        case AUX_CH_E:
        case AUX_CH_F:
        case AUX_CH_G:
                return DP_AUX_CH_CTL(aux_ch);
        default:
                MISSING_CASE(aux_ch);
                return DP_AUX_CH_CTL(AUX_CH_A);
        }
}

static i915_reg_t skl_aux_data_reg(struct intel_dp *intel_dp, int index)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        enum aux_ch aux_ch = dig_port->aux_ch;

        switch (aux_ch) {
        case AUX_CH_A:
        case AUX_CH_B:
        case AUX_CH_C:
        case AUX_CH_D:
        case AUX_CH_E:
        case AUX_CH_F:
        case AUX_CH_G:
                return DP_AUX_CH_DATA(aux_ch, index);
        default:
                MISSING_CASE(aux_ch);
                return DP_AUX_CH_DATA(AUX_CH_A, index);
        }
}

static void
intel_dp_aux_fini(struct intel_dp *intel_dp)
{
        kfree(intel_dp->aux.name);
}

static void
intel_dp_aux_init(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct intel_encoder *encoder = &dig_port->base;

        if (INTEL_GEN(dev_priv) >= 9) {
                intel_dp->aux_ch_ctl_reg = skl_aux_ctl_reg;
                intel_dp->aux_ch_data_reg = skl_aux_data_reg;
        } else if (HAS_PCH_SPLIT(dev_priv)) {
                intel_dp->aux_ch_ctl_reg = ilk_aux_ctl_reg;
                intel_dp->aux_ch_data_reg = ilk_aux_data_reg;
        } else {
                intel_dp->aux_ch_ctl_reg = g4x_aux_ctl_reg;
                intel_dp->aux_ch_data_reg = g4x_aux_data_reg;
        }

        if (INTEL_GEN(dev_priv) >= 9)
                intel_dp->get_aux_clock_divider = skl_get_aux_clock_divider;
        else if (IS_BROADWELL(dev_priv) || IS_HASWELL(dev_priv))
                intel_dp->get_aux_clock_divider = hsw_get_aux_clock_divider;
        else if (HAS_PCH_SPLIT(dev_priv))
                intel_dp->get_aux_clock_divider = ilk_get_aux_clock_divider;
        else
                intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;

        if (INTEL_GEN(dev_priv) >= 9)
                intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
        else
                intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;

        drm_dp_aux_init(&intel_dp->aux);

        /* Failure to allocate our preferred name is not critical */
        intel_dp->aux.name = kasprintf(GFP_KERNEL, "DPDDC-%c",
                                       port_name(encoder->port));
        intel_dp->aux.transfer = intel_dp_aux_transfer;
}

bool intel_dp_source_supports_hbr2(struct intel_dp *intel_dp)
{
        int max_rate = intel_dp->source_rates[intel_dp->num_source_rates - 1];

        return max_rate >= 540000;
}

bool intel_dp_source_supports_hbr3(struct intel_dp *intel_dp)
{
        int max_rate = intel_dp->source_rates[intel_dp->num_source_rates - 1];

        return max_rate >= 810000;
}

static void
intel_dp_set_clock(struct intel_encoder *encoder,
                   struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        const struct dp_link_dpll *divisor = NULL;
        int i, count = 0;

        if (IS_G4X(dev_priv)) {
                divisor = g4x_dpll;
                count = ARRAY_SIZE(g4x_dpll);
        } else if (HAS_PCH_SPLIT(dev_priv)) {
                divisor = pch_dpll;
                count = ARRAY_SIZE(pch_dpll);
        } else if (IS_CHERRYVIEW(dev_priv)) {
                divisor = chv_dpll;
                count = ARRAY_SIZE(chv_dpll);
        } else if (IS_VALLEYVIEW(dev_priv)) {
                divisor = vlv_dpll;
                count = ARRAY_SIZE(vlv_dpll);
        }

        if (divisor && count) {
                for (i = 0; i < count; i++) {
                        if (pipe_config->port_clock == divisor[i].clock) {
                                pipe_config->dpll = divisor[i].dpll;
                                pipe_config->clock_set = true;
                                break;
                        }
                }
        }
}

static void snprintf_int_array(char *str, size_t len,
                               const int *array, int nelem)
{
        int i;

        str[0] = '\0';

        for (i = 0; i < nelem; i++) {
                int r = snprintf(str, len, "%s%d", i ? ", " : "", array[i]);
                if (r >= len)
                        return;
                str += r;
                len -= r;
        }
}

static void intel_dp_print_rates(struct intel_dp *intel_dp)
{
        char str[128]; /* FIXME: too big for stack? */

        if ((drm_debug & DRM_UT_KMS) == 0)
                return;

        snprintf_int_array(str, sizeof(str),
                           intel_dp->source_rates, intel_dp->num_source_rates);
        DRM_DEBUG_KMS("source rates: %s\n", str);

        snprintf_int_array(str, sizeof(str),
                           intel_dp->sink_rates, intel_dp->num_sink_rates);
        DRM_DEBUG_KMS("sink rates: %s\n", str);

        snprintf_int_array(str, sizeof(str),
                           intel_dp->common_rates, intel_dp->num_common_rates);
        DRM_DEBUG_KMS("common rates: %s\n", str);
}

int
intel_dp_max_link_rate(struct intel_dp *intel_dp)
{
        int len;

        len = intel_dp_common_len_rate_limit(intel_dp, intel_dp->max_link_rate);
        if (WARN_ON(len <= 0))
                return 162000;

        return intel_dp->common_rates[len - 1];
}

int intel_dp_rate_select(struct intel_dp *intel_dp, int rate)
{
        int i = intel_dp_rate_index(intel_dp->sink_rates,
                                    intel_dp->num_sink_rates, rate);

        if (WARN_ON(i < 0))
                i = 0;

        return i;
}

void intel_dp_compute_rate(struct intel_dp *intel_dp, int port_clock,
                           u8 *link_bw, u8 *rate_select)
{
        /* eDP 1.4 rate select method. */
        if (intel_dp->use_rate_select) {
                *link_bw = 0;
                *rate_select =
                        intel_dp_rate_select(intel_dp, port_clock);
        } else {
                *link_bw = drm_dp_link_rate_to_bw_code(port_clock);
                *rate_select = 0;
        }
}

static bool intel_dp_source_supports_fec(struct intel_dp *intel_dp,
                                         const struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        /* On TGL, FEC is supported on all Pipes */
        if (INTEL_GEN(dev_priv) >= 12)
                return true;

        if (IS_GEN(dev_priv, 11) && pipe_config->cpu_transcoder != TRANSCODER_A)
                return true;

        return false;
}

static bool intel_dp_supports_fec(struct intel_dp *intel_dp,
                                  const struct intel_crtc_state *pipe_config)
{
        return intel_dp_source_supports_fec(intel_dp, pipe_config) &&
                drm_dp_sink_supports_fec(intel_dp->fec_capable);
}

static bool intel_dp_source_supports_dsc(struct intel_dp *intel_dp,
                                         const struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        if (!INTEL_INFO(dev_priv)->display.has_dsc)
                return false;

        /* On TGL, DSC is supported on all Pipes */
        if (INTEL_GEN(dev_priv) >= 12)
                return true;

        if (INTEL_GEN(dev_priv) >= 10 &&
            pipe_config->cpu_transcoder != TRANSCODER_A)
                return true;

        return false;
}

static bool intel_dp_supports_dsc(struct intel_dp *intel_dp,
                                  const struct intel_crtc_state *pipe_config)
{
        if (!intel_dp_is_edp(intel_dp) && !pipe_config->fec_enable)
                return false;

        return intel_dp_source_supports_dsc(intel_dp, pipe_config) &&
                drm_dp_sink_supports_dsc(intel_dp->dsc_dpcd);
}

static int intel_dp_compute_bpp(struct intel_dp *intel_dp,
                                struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_connector *intel_connector = intel_dp->attached_connector;
        int bpp, bpc;

        bpp = pipe_config->pipe_bpp;
        bpc = drm_dp_downstream_max_bpc(intel_dp->dpcd, intel_dp->downstream_ports);

        if (bpc > 0)
                bpp = min(bpp, 3*bpc);

        if (intel_dp_is_edp(intel_dp)) {
                /* Get bpp from vbt only for panels that dont have bpp in edid */
                if (intel_connector->base.display_info.bpc == 0 &&
                    dev_priv->vbt.edp.bpp && dev_priv->vbt.edp.bpp < bpp) {
                        DRM_DEBUG_KMS("clamping bpp for eDP panel to BIOS-provided %i\n",
                                      dev_priv->vbt.edp.bpp);
                        bpp = dev_priv->vbt.edp.bpp;
                }
        }

        return bpp;
}

/* Adjust link config limits based on compliance test requests. */
void
intel_dp_adjust_compliance_config(struct intel_dp *intel_dp,
                                  struct intel_crtc_state *pipe_config,
                                  struct link_config_limits *limits)
{
        /* For DP Compliance we override the computed bpp for the pipe */
        if (intel_dp->compliance.test_data.bpc != 0) {
                int bpp = 3 * intel_dp->compliance.test_data.bpc;

                limits->min_bpp = limits->max_bpp = bpp;
                pipe_config->dither_force_disable = bpp == 6 * 3;

                DRM_DEBUG_KMS("Setting pipe_bpp to %d\n", bpp);
        }

        /* Use values requested by Compliance Test Request */
        if (intel_dp->compliance.test_type == DP_TEST_LINK_TRAINING) {
                int index;

                /* Validate the compliance test data since max values
                 * might have changed due to link train fallback.
                 */
                if (intel_dp_link_params_valid(intel_dp, intel_dp->compliance.test_link_rate,
                                               intel_dp->compliance.test_lane_count)) {
                        index = intel_dp_rate_index(intel_dp->common_rates,
                                                    intel_dp->num_common_rates,
                                                    intel_dp->compliance.test_link_rate);
                        if (index >= 0)
                                limits->min_clock = limits->max_clock = index;
                        limits->min_lane_count = limits->max_lane_count =
                                intel_dp->compliance.test_lane_count;
                }
        }
}

static int intel_dp_output_bpp(const struct intel_crtc_state *crtc_state, int bpp)
{
        /*
         * bpp value was assumed to RGB format. And YCbCr 4:2:0 output
         * format of the number of bytes per pixel will be half the number
         * of bytes of RGB pixel.
         */
        if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420)
                bpp /= 2;

        return bpp;
}

/* Optimize link config in order: max bpp, min clock, min lanes */
static int
intel_dp_compute_link_config_wide(struct intel_dp *intel_dp,
                                  struct intel_crtc_state *pipe_config,
                                  const struct link_config_limits *limits)
{
        struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        int bpp, clock, lane_count;
        int mode_rate, link_clock, link_avail;

        for (bpp = limits->max_bpp; bpp >= limits->min_bpp; bpp -= 2 * 3) {
                int output_bpp = intel_dp_output_bpp(pipe_config, bpp);

                mode_rate = intel_dp_link_required(adjusted_mode->crtc_clock,
                                                   output_bpp);

                for (clock = limits->min_clock; clock <= limits->max_clock; clock++) {
                        for (lane_count = limits->min_lane_count;
                             lane_count <= limits->max_lane_count;
                             lane_count <<= 1) {
                                link_clock = intel_dp->common_rates[clock];
                                link_avail = intel_dp_max_data_rate(link_clock,
                                                                    lane_count);

                                if (mode_rate <= link_avail) {
                                        pipe_config->lane_count = lane_count;
                                        pipe_config->pipe_bpp = bpp;
                                        pipe_config->port_clock = link_clock;

                                        return 0;
                                }
                        }
                }
        }

        return -EINVAL;
}

static int intel_dp_dsc_compute_bpp(struct intel_dp *intel_dp, u8 dsc_max_bpc)
{
        int i, num_bpc;
        u8 dsc_bpc[3] = {0};

        num_bpc = drm_dp_dsc_sink_supported_input_bpcs(intel_dp->dsc_dpcd,
                                                       dsc_bpc);
        for (i = 0; i < num_bpc; i++) {
                if (dsc_max_bpc >= dsc_bpc[i])
                        return dsc_bpc[i] * 3;
        }

        return 0;
}

static int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
                                       struct intel_crtc_state *pipe_config,
                                       struct drm_connector_state *conn_state,
                                       struct link_config_limits *limits)
{
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
        struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        u8 dsc_max_bpc;
        int pipe_bpp;
        int ret;

        pipe_config->fec_enable = !intel_dp_is_edp(intel_dp) &&
                intel_dp_supports_fec(intel_dp, pipe_config);

        if (!intel_dp_supports_dsc(intel_dp, pipe_config))
                return -EINVAL;

        /* Max DSC Input BPC for ICL is 10 and for TGL+ is 12 */
        if (INTEL_GEN(dev_priv) >= 12)
                dsc_max_bpc = min_t(u8, 12, conn_state->max_requested_bpc);
        else
                dsc_max_bpc = min_t(u8, 10,
                                    conn_state->max_requested_bpc);

        pipe_bpp = intel_dp_dsc_compute_bpp(intel_dp, dsc_max_bpc);

        /* Min Input BPC for ICL+ is 8 */
        if (pipe_bpp < 8 * 3) {
                DRM_DEBUG_KMS("No DSC support for less than 8bpc\n");
                return -EINVAL;
        }

        /*
         * For now enable DSC for max bpp, max link rate, max lane count.
         * Optimize this later for the minimum possible link rate/lane count
         * with DSC enabled for the requested mode.
         */
        pipe_config->pipe_bpp = pipe_bpp;
        pipe_config->port_clock = intel_dp->common_rates[limits->max_clock];
        pipe_config->lane_count = limits->max_lane_count;

        if (intel_dp_is_edp(intel_dp)) {
                pipe_config->dsc.compressed_bpp =
                        min_t(u16, drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd) >> 4,
                              pipe_config->pipe_bpp);
                pipe_config->dsc.slice_count =
                        drm_dp_dsc_sink_max_slice_count(intel_dp->dsc_dpcd,
                                                        true);
        } else {
                u16 dsc_max_output_bpp;
                u8 dsc_dp_slice_count;

                dsc_max_output_bpp =
                        intel_dp_dsc_get_output_bpp(dev_priv,
                                                    pipe_config->port_clock,
                                                    pipe_config->lane_count,
                                                    adjusted_mode->crtc_clock,
                                                    adjusted_mode->crtc_hdisplay);
                dsc_dp_slice_count =
                        intel_dp_dsc_get_slice_count(intel_dp,
                                                     adjusted_mode->crtc_clock,
                                                     adjusted_mode->crtc_hdisplay);
                if (!dsc_max_output_bpp || !dsc_dp_slice_count) {
                        DRM_DEBUG_KMS("Compressed BPP/Slice Count not supported\n");
                        return -EINVAL;
                }
                pipe_config->dsc.compressed_bpp = min_t(u16,
                                                               dsc_max_output_bpp >> 4,
                                                               pipe_config->pipe_bpp);
                pipe_config->dsc.slice_count = dsc_dp_slice_count;
        }
        /*
         * VDSC engine operates at 1 Pixel per clock, so if peak pixel rate
         * is greater than the maximum Cdclock and if slice count is even
         * then we need to use 2 VDSC instances.
         */
        if (adjusted_mode->crtc_clock > dev_priv->max_cdclk_freq) {
                if (pipe_config->dsc.slice_count > 1) {
                        pipe_config->dsc.dsc_split = true;
                } else {
                        DRM_DEBUG_KMS("Cannot split stream to use 2 VDSC instances\n");
                        return -EINVAL;
                }
        }

        ret = intel_dp_compute_dsc_params(intel_dp, pipe_config);
        if (ret < 0) {
                DRM_DEBUG_KMS("Cannot compute valid DSC parameters for Input Bpp = %d "
                              "Compressed BPP = %d\n",
                              pipe_config->pipe_bpp,
                              pipe_config->dsc.compressed_bpp);
                return ret;
        }

        pipe_config->dsc.compression_enable = true;
        DRM_DEBUG_KMS("DP DSC computed with Input Bpp = %d "
                      "Compressed Bpp = %d Slice Count = %d\n",
                      pipe_config->pipe_bpp,
                      pipe_config->dsc.compressed_bpp,
                      pipe_config->dsc.slice_count);

        return 0;
}

int intel_dp_min_bpp(const struct intel_crtc_state *crtc_state)
{
        if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_RGB)
                return 6 * 3;
        else
                return 8 * 3;
}

static int
intel_dp_compute_link_config(struct intel_encoder *encoder,
                             struct intel_crtc_state *pipe_config,
                             struct drm_connector_state *conn_state)
{
        struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct link_config_limits limits;
        int common_len;
        int ret;

        common_len = intel_dp_common_len_rate_limit(intel_dp,
                                                    intel_dp->max_link_rate);

        /* No common link rates between source and sink */
        WARN_ON(common_len <= 0);

        limits.min_clock = 0;
        limits.max_clock = common_len - 1;

        limits.min_lane_count = 1;
        limits.max_lane_count = intel_dp_max_lane_count(intel_dp);

        limits.min_bpp = intel_dp_min_bpp(pipe_config);
        limits.max_bpp = intel_dp_compute_bpp(intel_dp, pipe_config);

        if (intel_dp_is_edp(intel_dp)) {
                /*
                 * Use the maximum clock and number of lanes the eDP panel
                 * advertizes being capable of. The panels are generally
                 * designed to support only a single clock and lane
                 * configuration, and typically these values correspond to the
                 * native resolution of the panel.
                 */
                limits.min_lane_count = limits.max_lane_count;
                limits.min_clock = limits.max_clock;
        }

        intel_dp_adjust_compliance_config(intel_dp, pipe_config, &limits);

        DRM_DEBUG_KMS("DP link computation with max lane count %i "
                      "max rate %d max bpp %d pixel clock %iKHz\n",
                      limits.max_lane_count,
                      intel_dp->common_rates[limits.max_clock],
                      limits.max_bpp, adjusted_mode->crtc_clock);

        /*
         * Optimize for slow and wide. This is the place to add alternative
         * optimization policy.
         */
        ret = intel_dp_compute_link_config_wide(intel_dp, pipe_config, &limits);

        /* enable compression if the mode doesn't fit available BW */
        DRM_DEBUG_KMS("Force DSC en = %d\n", intel_dp->force_dsc_en);
        if (ret || intel_dp->force_dsc_en) {
                ret = intel_dp_dsc_compute_config(intel_dp, pipe_config,
                                                  conn_state, &limits);
                if (ret < 0)
                        return ret;
        }

        if (pipe_config->dsc.compression_enable) {
                DRM_DEBUG_KMS("DP lane count %d clock %d Input bpp %d Compressed bpp %d\n",
                              pipe_config->lane_count, pipe_config->port_clock,
                              pipe_config->pipe_bpp,
                              pipe_config->dsc.compressed_bpp);

                DRM_DEBUG_KMS("DP link rate required %i available %i\n",
                              intel_dp_link_required(adjusted_mode->crtc_clock,
                                                     pipe_config->dsc.compressed_bpp),
                              intel_dp_max_data_rate(pipe_config->port_clock,
                                                     pipe_config->lane_count));
        } else {
                DRM_DEBUG_KMS("DP lane count %d clock %d bpp %d\n",
                              pipe_config->lane_count, pipe_config->port_clock,
                              pipe_config->pipe_bpp);

                DRM_DEBUG_KMS("DP link rate required %i available %i\n",
                              intel_dp_link_required(adjusted_mode->crtc_clock,
                                                     pipe_config->pipe_bpp),
                              intel_dp_max_data_rate(pipe_config->port_clock,
                                                     pipe_config->lane_count));
        }
        return 0;
}

static int
intel_dp_ycbcr420_config(struct intel_dp *intel_dp,
                         struct drm_connector *connector,
                         struct intel_crtc_state *crtc_state)
{
        const struct drm_display_info *info = &connector->display_info;
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->base.adjusted_mode;
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
        int ret;

        if (!drm_mode_is_420_only(info, adjusted_mode) ||
            !intel_dp_get_colorimetry_status(intel_dp) ||
            !connector->ycbcr_420_allowed)
                return 0;

        crtc_state->output_format = INTEL_OUTPUT_FORMAT_YCBCR420;

        /* YCBCR 420 output conversion needs a scaler */
        ret = skl_update_scaler_crtc(crtc_state);
        if (ret) {
                DRM_DEBUG_KMS("Scaler allocation for output failed\n");
                return ret;
        }

        intel_pch_panel_fitting(crtc, crtc_state, DRM_MODE_SCALE_FULLSCREEN);

        return 0;
}

bool intel_dp_limited_color_range(const struct intel_crtc_state *crtc_state,
                                  const struct drm_connector_state *conn_state)
{
        const struct intel_digital_connector_state *intel_conn_state =
                to_intel_digital_connector_state(conn_state);
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->base.adjusted_mode;

        /*
         * Our YCbCr output is always limited range.
         * crtc_state->limited_color_range only applies to RGB,
         * and it must never be set for YCbCr or we risk setting
         * some conflicting bits in PIPECONF which will mess up
         * the colors on the monitor.
         */
        if (crtc_state->output_format != INTEL_OUTPUT_FORMAT_RGB)
                return false;

        if (intel_conn_state->broadcast_rgb == INTEL_BROADCAST_RGB_AUTO) {
                /*
                 * See:
                 * CEA-861-E - 5.1 Default Encoding Parameters
                 * VESA DisplayPort Ver.1.2a - 5.1.1.1 Video Colorimetry
                 */
                return crtc_state->pipe_bpp != 18 &&
                        drm_default_rgb_quant_range(adjusted_mode) ==
                        HDMI_QUANTIZATION_RANGE_LIMITED;
        } else {
                return intel_conn_state->broadcast_rgb ==
                        INTEL_BROADCAST_RGB_LIMITED;
        }
}

int
intel_dp_compute_config(struct intel_encoder *encoder,
                        struct intel_crtc_state *pipe_config,
                        struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct intel_lspcon *lspcon = enc_to_intel_lspcon(&encoder->base);
        enum port port = encoder->port;
        struct intel_crtc *intel_crtc = to_intel_crtc(pipe_config->base.crtc);
        struct intel_connector *intel_connector = intel_dp->attached_connector;
        struct intel_digital_connector_state *intel_conn_state =
                to_intel_digital_connector_state(conn_state);
        bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
                                           DP_DPCD_QUIRK_CONSTANT_N);
        int ret = 0, output_bpp;

        if (HAS_PCH_SPLIT(dev_priv) && !HAS_DDI(dev_priv) && port != PORT_A)
                pipe_config->has_pch_encoder = true;

        pipe_config->output_format = INTEL_OUTPUT_FORMAT_RGB;

        if (lspcon->active)
                lspcon_ycbcr420_config(&intel_connector->base, pipe_config);
        else
                ret = intel_dp_ycbcr420_config(intel_dp, &intel_connector->base,
                                               pipe_config);

        if (ret)
                return ret;

        pipe_config->has_drrs = false;
        if (IS_G4X(dev_priv) || port == PORT_A)
                pipe_config->has_audio = false;
        else if (intel_conn_state->force_audio == HDMI_AUDIO_AUTO)
                pipe_config->has_audio = intel_dp->has_audio;
        else
                pipe_config->has_audio = intel_conn_state->force_audio == HDMI_AUDIO_ON;

        if (intel_dp_is_edp(intel_dp) && intel_connector->panel.fixed_mode) {
                intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
                                       adjusted_mode);

                if (INTEL_GEN(dev_priv) >= 9) {
                        ret = skl_update_scaler_crtc(pipe_config);
                        if (ret)
                                return ret;
                }

                if (HAS_GMCH(dev_priv))
                        intel_gmch_panel_fitting(intel_crtc, pipe_config,
                                                 conn_state->scaling_mode);
                else
                        intel_pch_panel_fitting(intel_crtc, pipe_config,
                                                conn_state->scaling_mode);
        }

        if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return -EINVAL;

        if (HAS_GMCH(dev_priv) &&
            adjusted_mode->flags & DRM_MODE_FLAG_INTERLACE)
                return -EINVAL;

        if (adjusted_mode->flags & DRM_MODE_FLAG_DBLCLK)
                return -EINVAL;

        if (intel_dp_hdisplay_bad(dev_priv, adjusted_mode->crtc_hdisplay))
                return -EINVAL;

        ret = intel_dp_compute_link_config(encoder, pipe_config, conn_state);
        if (ret < 0)
                return ret;

        pipe_config->limited_color_range =
                intel_dp_limited_color_range(pipe_config, conn_state);

        if (pipe_config->dsc.compression_enable)
                output_bpp = pipe_config->dsc.compressed_bpp;
        else
                output_bpp = intel_dp_output_bpp(pipe_config, pipe_config->pipe_bpp);

        intel_link_compute_m_n(output_bpp,
                               pipe_config->lane_count,
                               adjusted_mode->crtc_clock,
                               pipe_config->port_clock,
                               &pipe_config->dp_m_n,
                               constant_n, pipe_config->fec_enable);

        if (intel_connector->panel.downclock_mode != NULL &&
                dev_priv->drrs.type == SEAMLESS_DRRS_SUPPORT) {
                        pipe_config->has_drrs = true;
                        intel_link_compute_m_n(output_bpp,
                                               pipe_config->lane_count,
                                               intel_connector->panel.downclock_mode->clock,
                                               pipe_config->port_clock,
                                               &pipe_config->dp_m2_n2,
                                               constant_n, pipe_config->fec_enable);
        }

        if (!HAS_DDI(dev_priv))
                intel_dp_set_clock(encoder, pipe_config);

        intel_psr_compute_config(intel_dp, pipe_config);

        return 0;
}

void intel_dp_set_link_params(struct intel_dp *intel_dp,
                              int link_rate, u8 lane_count,
                              bool link_mst)
{
        intel_dp->link_trained = false;
        intel_dp->link_rate = link_rate;
        intel_dp->lane_count = lane_count;
        intel_dp->link_mst = link_mst;
}

static void intel_dp_prepare(struct intel_encoder *encoder,
                             const struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        enum port port = encoder->port;
        struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);
        const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;

        intel_dp_set_link_params(intel_dp, pipe_config->port_clock,
                                 pipe_config->lane_count,
                                 intel_crtc_has_type(pipe_config,
                                                     INTEL_OUTPUT_DP_MST));

        intel_dp->regs.dp_tp_ctl = DP_TP_CTL(port);
        intel_dp->regs.dp_tp_status = DP_TP_STATUS(port);

        /*
         * There are four kinds of DP registers:
         *
         *      IBX PCH
         *      SNB CPU
         *      IVB CPU
         *      CPT PCH
         *
         * IBX PCH and CPU are the same for almost everything,
         * except that the CPU DP PLL is configured in this
         * register
         *
         * CPT PCH is quite different, having many bits moved
         * to the TRANS_DP_CTL register instead. That
         * configuration happens (oddly) in ironlake_pch_enable
         */

        /* Preserve the BIOS-computed detected bit. This is
         * supposed to be read-only.
         */
        intel_dp->DP = I915_READ(intel_dp->output_reg) & DP_DETECTED;

        /* Handle DP bits in common between all three register formats */
        intel_dp->DP |= DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0;
        intel_dp->DP |= DP_PORT_WIDTH(pipe_config->lane_count);

        /* Split out the IBX/CPU vs CPT settings */

        if (IS_IVYBRIDGE(dev_priv) && port == PORT_A) {
                if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
                        intel_dp->DP |= DP_SYNC_HS_HIGH;
                if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
                        intel_dp->DP |= DP_SYNC_VS_HIGH;
                intel_dp->DP |= DP_LINK_TRAIN_OFF_CPT;

                if (drm_dp_enhanced_frame_cap(intel_dp->dpcd))
                        intel_dp->DP |= DP_ENHANCED_FRAMING;

                intel_dp->DP |= DP_PIPE_SEL_IVB(crtc->pipe);
        } else if (HAS_PCH_CPT(dev_priv) && port != PORT_A) {
                u32 trans_dp;

                intel_dp->DP |= DP_LINK_TRAIN_OFF_CPT;

                trans_dp = I915_READ(TRANS_DP_CTL(crtc->pipe));
                if (drm_dp_enhanced_frame_cap(intel_dp->dpcd))
                        trans_dp |= TRANS_DP_ENH_FRAMING;
                else
                        trans_dp &= ~TRANS_DP_ENH_FRAMING;
                I915_WRITE(TRANS_DP_CTL(crtc->pipe), trans_dp);
        } else {
                if (IS_G4X(dev_priv) && pipe_config->limited_color_range)
                        intel_dp->DP |= DP_COLOR_RANGE_16_235;

                if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
                        intel_dp->DP |= DP_SYNC_HS_HIGH;
                if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
                        intel_dp->DP |= DP_SYNC_VS_HIGH;
                intel_dp->DP |= DP_LINK_TRAIN_OFF;

                if (drm_dp_enhanced_frame_cap(intel_dp->dpcd))
                        intel_dp->DP |= DP_ENHANCED_FRAMING;

                if (IS_CHERRYVIEW(dev_priv))
                        intel_dp->DP |= DP_PIPE_SEL_CHV(crtc->pipe);
                else
                        intel_dp->DP |= DP_PIPE_SEL(crtc->pipe);
        }
}

#define IDLE_ON_MASK            (PP_ON | PP_SEQUENCE_MASK | 0                     | PP_SEQUENCE_STATE_MASK)
#define IDLE_ON_VALUE           (PP_ON | PP_SEQUENCE_NONE | 0                     | PP_SEQUENCE_STATE_ON_IDLE)

#define IDLE_OFF_MASK           (PP_ON | PP_SEQUENCE_MASK | 0                     | 0)
#define IDLE_OFF_VALUE          (0     | PP_SEQUENCE_NONE | 0                     | 0)

#define IDLE_CYCLE_MASK         (PP_ON | PP_SEQUENCE_MASK | PP_CYCLE_DELAY_ACTIVE | PP_SEQUENCE_STATE_MASK)
#define IDLE_CYCLE_VALUE        (0     | PP_SEQUENCE_NONE | 0                     | PP_SEQUENCE_STATE_OFF_IDLE)

static void intel_pps_verify_state(struct intel_dp *intel_dp);

static void wait_panel_status(struct intel_dp *intel_dp,
                                       u32 mask,
                                       u32 value)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        i915_reg_t pp_stat_reg, pp_ctrl_reg;

        lockdep_assert_held(&dev_priv->pps_mutex);

        intel_pps_verify_state(intel_dp);

        pp_stat_reg = _pp_stat_reg(intel_dp);
        pp_ctrl_reg = _pp_ctrl_reg(intel_dp);

        DRM_DEBUG_KMS("mask %08x value %08x status %08x control %08x\n",
                        mask, value,
                        I915_READ(pp_stat_reg),
                        I915_READ(pp_ctrl_reg));

        if (intel_de_wait_for_register(dev_priv, pp_stat_reg,
                                       mask, value, 5000))
                DRM_ERROR("Panel status timeout: status %08x control %08x\n",
                                I915_READ(pp_stat_reg),
                                I915_READ(pp_ctrl_reg));

        DRM_DEBUG_KMS("Wait complete\n");
}

static void wait_panel_on(struct intel_dp *intel_dp)
{
        DRM_DEBUG_KMS("Wait for panel power on\n");
        wait_panel_status(intel_dp, IDLE_ON_MASK, IDLE_ON_VALUE);
}

static void wait_panel_off(struct intel_dp *intel_dp)
{
        DRM_DEBUG_KMS("Wait for panel power off time\n");
        wait_panel_status(intel_dp, IDLE_OFF_MASK, IDLE_OFF_VALUE);
}

static void wait_panel_power_cycle(struct intel_dp *intel_dp)
{
        ktime_t panel_power_on_time;
        s64 panel_power_off_duration;

        DRM_DEBUG_KMS("Wait for panel power cycle\n");

        /* take the difference of currrent time and panel power off time
         * and then make panel wait for t11_t12 if needed. */
        panel_power_on_time = ktime_get_boottime();
        panel_power_off_duration = ktime_ms_delta(panel_power_on_time, intel_dp->panel_power_off_time);

        /* When we disable the VDD override bit last we have to do the manual
         * wait. */
        if (panel_power_off_duration < (s64)intel_dp->panel_power_cycle_delay)
                wait_remaining_ms_from_jiffies(jiffies,
                                       intel_dp->panel_power_cycle_delay - panel_power_off_duration);

        wait_panel_status(intel_dp, IDLE_CYCLE_MASK, IDLE_CYCLE_VALUE);
}

static void wait_backlight_on(struct intel_dp *intel_dp)
{
        wait_remaining_ms_from_jiffies(intel_dp->last_power_on,
                                       intel_dp->backlight_on_delay);
}

static void edp_wait_backlight_off(struct intel_dp *intel_dp)
{
        wait_remaining_ms_from_jiffies(intel_dp->last_backlight_off,
                                       intel_dp->backlight_off_delay);
}

/* Read the current pp_control value, unlocking the register if it
 * is locked
 */

static  u32 ironlake_get_pp_control(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        u32 control;

        lockdep_assert_held(&dev_priv->pps_mutex);

        control = I915_READ(_pp_ctrl_reg(intel_dp));
        if (WARN_ON(!HAS_DDI(dev_priv) &&
                    (control & PANEL_UNLOCK_MASK) != PANEL_UNLOCK_REGS)) {
                control &= ~PANEL_UNLOCK_MASK;
                control |= PANEL_UNLOCK_REGS;
        }
        return control;
}

/*
 * Must be paired with edp_panel_vdd_off().
 * Must hold pps_mutex around the whole on/off sequence.
 * Can be nested with intel_edp_panel_vdd_{on,off}() calls.
 */
static bool edp_panel_vdd_on(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        u32 pp;
        i915_reg_t pp_stat_reg, pp_ctrl_reg;
        bool need_to_disable = !intel_dp->want_panel_vdd;

        lockdep_assert_held(&dev_priv->pps_mutex);

        if (!intel_dp_is_edp(intel_dp))
                return false;

        cancel_delayed_work(&intel_dp->panel_vdd_work);
        intel_dp->want_panel_vdd = true;

        if (edp_have_panel_vdd(intel_dp))
                return need_to_disable;

        intel_display_power_get(dev_priv,
                                intel_aux_power_domain(intel_dig_port));

        DRM_DEBUG_KMS("Turning [ENCODER:%d:%s] VDD on\n",
                      intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name);

        if (!edp_have_panel_power(intel_dp))
                wait_panel_power_cycle(intel_dp);

        pp = ironlake_get_pp_control(intel_dp);
        pp |= EDP_FORCE_VDD;

        pp_stat_reg = _pp_stat_reg(intel_dp);
        pp_ctrl_reg = _pp_ctrl_reg(intel_dp);

        I915_WRITE(pp_ctrl_reg, pp);
        POSTING_READ(pp_ctrl_reg);
        DRM_DEBUG_KMS("PP_STATUS: 0x%08x PP_CONTROL: 0x%08x\n",
                        I915_READ(pp_stat_reg), I915_READ(pp_ctrl_reg));
        /*
         * If the panel wasn't on, delay before accessing aux channel
         */
        if (!edp_have_panel_power(intel_dp)) {
                DRM_DEBUG_KMS("[ENCODER:%d:%s] panel power wasn't enabled\n",
                              intel_dig_port->base.base.base.id,
                              intel_dig_port->base.base.name);
                msleep(intel_dp->panel_power_up_delay);
        }

        return need_to_disable;
}

/*
 * Must be paired with intel_edp_panel_vdd_off() or
 * intel_edp_panel_off().
 * Nested calls to these functions are not allowed since
 * we drop the lock. Caller must use some higher level
 * locking to prevent nested calls from other threads.
 */
void intel_edp_panel_vdd_on(struct intel_dp *intel_dp)
{
        intel_wakeref_t wakeref;
        bool vdd;

        if (!intel_dp_is_edp(intel_dp))
                return;

        vdd = false;
        with_pps_lock(intel_dp, wakeref)
                vdd = edp_panel_vdd_on(intel_dp);
        I915_STATE_WARN(!vdd, "[ENCODER:%d:%s] VDD already requested on\n",
                        dp_to_dig_port(intel_dp)->base.base.base.id,
                        dp_to_dig_port(intel_dp)->base.base.name);
}

static void edp_panel_vdd_off_sync(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port =
                dp_to_dig_port(intel_dp);
        u32 pp;
        i915_reg_t pp_stat_reg, pp_ctrl_reg;

        lockdep_assert_held(&dev_priv->pps_mutex);

        WARN_ON(intel_dp->want_panel_vdd);

        if (!edp_have_panel_vdd(intel_dp))
                return;

        DRM_DEBUG_KMS("Turning [ENCODER:%d:%s] VDD off\n",
                      intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name);

        pp = ironlake_get_pp_control(intel_dp);
        pp &= ~EDP_FORCE_VDD;

        pp_ctrl_reg = _pp_ctrl_reg(intel_dp);
        pp_stat_reg = _pp_stat_reg(intel_dp);

        I915_WRITE(pp_ctrl_reg, pp);
        POSTING_READ(pp_ctrl_reg);

        /* Make sure sequencer is idle before allowing subsequent activity */
        DRM_DEBUG_KMS("PP_STATUS: 0x%08x PP_CONTROL: 0x%08x\n",
        I915_READ(pp_stat_reg), I915_READ(pp_ctrl_reg));

        if ((pp & PANEL_POWER_ON) == 0)
                intel_dp->panel_power_off_time = ktime_get_boottime();

        intel_display_power_put_unchecked(dev_priv,
                                          intel_aux_power_domain(intel_dig_port));
}

static void edp_panel_vdd_work(struct work_struct *__work)
{
        struct intel_dp *intel_dp =
                container_of(to_delayed_work(__work),
                             struct intel_dp, panel_vdd_work);
        intel_wakeref_t wakeref;

        with_pps_lock(intel_dp, wakeref) {
                if (!intel_dp->want_panel_vdd)
                        edp_panel_vdd_off_sync(intel_dp);
        }
}

static void edp_panel_vdd_schedule_off(struct intel_dp *intel_dp)
{
        unsigned long delay;

        /*
         * Queue the timer to fire a long time from now (relative to the power
         * down delay) to keep the panel power up across a sequence of
         * operations.
         */
        delay = msecs_to_jiffies(intel_dp->panel_power_cycle_delay * 5);
        schedule_delayed_work(&intel_dp->panel_vdd_work, delay);
}

/*
 * Must be paired with edp_panel_vdd_on().
 * Must hold pps_mutex around the whole on/off sequence.
 * Can be nested with intel_edp_panel_vdd_{on,off}() calls.
 */
static void edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        lockdep_assert_held(&dev_priv->pps_mutex);

        if (!intel_dp_is_edp(intel_dp))
                return;

        I915_STATE_WARN(!intel_dp->want_panel_vdd, "[ENCODER:%d:%s] VDD not forced on",
                        dp_to_dig_port(intel_dp)->base.base.base.id,
                        dp_to_dig_port(intel_dp)->base.base.name);

        intel_dp->want_panel_vdd = false;

        if (sync)
                edp_panel_vdd_off_sync(intel_dp);
        else
                edp_panel_vdd_schedule_off(intel_dp);
}

static void edp_panel_on(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        u32 pp;
        i915_reg_t pp_ctrl_reg;

        lockdep_assert_held(&dev_priv->pps_mutex);

        if (!intel_dp_is_edp(intel_dp))
                return;

        DRM_DEBUG_KMS("Turn [ENCODER:%d:%s] panel power on\n",
                      dp_to_dig_port(intel_dp)->base.base.base.id,
                      dp_to_dig_port(intel_dp)->base.base.name);

        if (WARN(edp_have_panel_power(intel_dp),
                 "[ENCODER:%d:%s] panel power already on\n",
                 dp_to_dig_port(intel_dp)->base.base.base.id,
                 dp_to_dig_port(intel_dp)->base.base.name))
                return;

        wait_panel_power_cycle(intel_dp);

        pp_ctrl_reg = _pp_ctrl_reg(intel_dp);
        pp = ironlake_get_pp_control(intel_dp);
        if (IS_GEN(dev_priv, 5)) {
                /* ILK workaround: disable reset around power sequence */
                pp &= ~PANEL_POWER_RESET;
                I915_WRITE(pp_ctrl_reg, pp);
                POSTING_READ(pp_ctrl_reg);
        }

        pp |= PANEL_POWER_ON;
        if (!IS_GEN(dev_priv, 5))
                pp |= PANEL_POWER_RESET;

        I915_WRITE(pp_ctrl_reg, pp);
        POSTING_READ(pp_ctrl_reg);

        wait_panel_on(intel_dp);
        intel_dp->last_power_on = jiffies;

        if (IS_GEN(dev_priv, 5)) {
                pp |= PANEL_POWER_RESET; /* restore panel reset bit */
                I915_WRITE(pp_ctrl_reg, pp);
                POSTING_READ(pp_ctrl_reg);
        }
}

void intel_edp_panel_on(struct intel_dp *intel_dp)
{
        intel_wakeref_t wakeref;

        if (!intel_dp_is_edp(intel_dp))
                return;

        with_pps_lock(intel_dp, wakeref)
                edp_panel_on(intel_dp);
}


static void edp_panel_off(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        u32 pp;
        i915_reg_t pp_ctrl_reg;

        lockdep_assert_held(&dev_priv->pps_mutex);

        if (!intel_dp_is_edp(intel_dp))
                return;

        DRM_DEBUG_KMS("Turn [ENCODER:%d:%s] panel power off\n",
                      dig_port->base.base.base.id, dig_port->base.base.name);

        WARN(!intel_dp->want_panel_vdd, "Need [ENCODER:%d:%s] VDD to turn off panel\n",
             dig_port->base.base.base.id, dig_port->base.base.name);

        pp = ironlake_get_pp_control(intel_dp);
        /* We need to switch off panel power _and_ force vdd, for otherwise some
         * panels get very unhappy and cease to work. */
        pp &= ~(PANEL_POWER_ON | PANEL_POWER_RESET | EDP_FORCE_VDD |
                EDP_BLC_ENABLE);

        pp_ctrl_reg = _pp_ctrl_reg(intel_dp);

        intel_dp->want_panel_vdd = false;

        I915_WRITE(pp_ctrl_reg, pp);
        POSTING_READ(pp_ctrl_reg);

        wait_panel_off(intel_dp);
        intel_dp->panel_power_off_time = ktime_get_boottime();

        /* We got a reference when we enabled the VDD. */
        intel_display_power_put_unchecked(dev_priv, intel_aux_power_domain(dig_port));
}

void intel_edp_panel_off(struct intel_dp *intel_dp)
{
        intel_wakeref_t wakeref;

        if (!intel_dp_is_edp(intel_dp))
                return;

        with_pps_lock(intel_dp, wakeref)
                edp_panel_off(intel_dp);
}

/* Enable backlight in the panel power control. */
static void _intel_edp_backlight_on(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        intel_wakeref_t wakeref;

        /*
         * If we enable the backlight right away following a panel power
         * on, we may see slight flicker as the panel syncs with the eDP
         * link.  So delay a bit to make sure the image is solid before
         * allowing it to appear.
         */
        wait_backlight_on(intel_dp);

        with_pps_lock(intel_dp, wakeref) {
                i915_reg_t pp_ctrl_reg = _pp_ctrl_reg(intel_dp);
                u32 pp;

                pp = ironlake_get_pp_control(intel_dp);
                pp |= EDP_BLC_ENABLE;

                I915_WRITE(pp_ctrl_reg, pp);
                POSTING_READ(pp_ctrl_reg);
        }
}

/* Enable backlight PWM and backlight PP control. */
void intel_edp_backlight_on(const struct intel_crtc_state *crtc_state,
                            const struct drm_connector_state *conn_state)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(conn_state->best_encoder);

        if (!intel_dp_is_edp(intel_dp))
                return;

        DRM_DEBUG_KMS("\n");

        intel_panel_enable_backlight(crtc_state, conn_state);
        _intel_edp_backlight_on(intel_dp);
}

/* Disable backlight in the panel power control. */
static void _intel_edp_backlight_off(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        intel_wakeref_t wakeref;

        if (!intel_dp_is_edp(intel_dp))
                return;

        with_pps_lock(intel_dp, wakeref) {
                i915_reg_t pp_ctrl_reg = _pp_ctrl_reg(intel_dp);
                u32 pp;

                pp = ironlake_get_pp_control(intel_dp);
                pp &= ~EDP_BLC_ENABLE;

                I915_WRITE(pp_ctrl_reg, pp);
                POSTING_READ(pp_ctrl_reg);
        }

        intel_dp->last_backlight_off = jiffies;
        edp_wait_backlight_off(intel_dp);
}

/* Disable backlight PP control and backlight PWM. */
void intel_edp_backlight_off(const struct drm_connector_state *old_conn_state)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(old_conn_state->best_encoder);

        if (!intel_dp_is_edp(intel_dp))
                return;

        DRM_DEBUG_KMS("\n");

        _intel_edp_backlight_off(intel_dp);
        intel_panel_disable_backlight(old_conn_state);
}

/*
 * Hook for controlling the panel power control backlight through the bl_power
 * sysfs attribute. Take care to handle multiple calls.
 */
static void intel_edp_backlight_power(struct intel_connector *connector,
                                      bool enable)
{
        struct intel_dp *intel_dp = intel_attached_dp(&connector->base);
        intel_wakeref_t wakeref;
        bool is_enabled;

        is_enabled = false;
        with_pps_lock(intel_dp, wakeref)
                is_enabled = ironlake_get_pp_control(intel_dp) & EDP_BLC_ENABLE;
        if (is_enabled == enable)
                return;

        DRM_DEBUG_KMS("panel power control backlight %s\n",
                      enable ? "enable" : "disable");

        if (enable)
                _intel_edp_backlight_on(intel_dp);
        else
                _intel_edp_backlight_off(intel_dp);
}

static void assert_dp_port(struct intel_dp *intel_dp, bool state)
{
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
        bool cur_state = I915_READ(intel_dp->output_reg) & DP_PORT_EN;

        I915_STATE_WARN(cur_state != state,
                        "[ENCODER:%d:%s] state assertion failure (expected %s, current %s)\n",
                        dig_port->base.base.base.id, dig_port->base.base.name,
                        onoff(state), onoff(cur_state));
}
#define assert_dp_port_disabled(d) assert_dp_port((d), false)

static void assert_edp_pll(struct drm_i915_private *dev_priv, bool state)
{
        bool cur_state = I915_READ(DP_A) & DP_PLL_ENABLE;

        I915_STATE_WARN(cur_state != state,
                        "eDP PLL state assertion failure (expected %s, current %s)\n",
                        onoff(state), onoff(cur_state));
}
#define assert_edp_pll_enabled(d) assert_edp_pll((d), true)
#define assert_edp_pll_disabled(d) assert_edp_pll((d), false)

static void ironlake_edp_pll_on(struct intel_dp *intel_dp,
                                const struct intel_crtc_state *pipe_config)
{
        struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);
        struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);

        assert_pipe_disabled(dev_priv, crtc->pipe);
        assert_dp_port_disabled(intel_dp);
        assert_edp_pll_disabled(dev_priv);

        DRM_DEBUG_KMS("enabling eDP PLL for clock %d\n",
                      pipe_config->port_clock);

        intel_dp->DP &= ~DP_PLL_FREQ_MASK;

        if (pipe_config->port_clock == 162000)
                intel_dp->DP |= DP_PLL_FREQ_162MHZ;
        else
                intel_dp->DP |= DP_PLL_FREQ_270MHZ;

        I915_WRITE(DP_A, intel_dp->DP);
        POSTING_READ(DP_A);
        udelay(500);

        /*
         * [DevILK] Work around required when enabling DP PLL
         * while a pipe is enabled going to FDI:
         * 1. Wait for the start of vertical blank on the enabled pipe going to FDI
         * 2. Program DP PLL enable
         */
        if (IS_GEN(dev_priv, 5))
                intel_wait_for_vblank_if_active(dev_priv, !crtc->pipe);

        intel_dp->DP |= DP_PLL_ENABLE;

        I915_WRITE(DP_A, intel_dp->DP);
        POSTING_READ(DP_A);
        udelay(200);
}

static void ironlake_edp_pll_off(struct intel_dp *intel_dp,
                                 const struct intel_crtc_state *old_crtc_state)
{
        struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->base.crtc);
        struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);

        assert_pipe_disabled(dev_priv, crtc->pipe);
        assert_dp_port_disabled(intel_dp);
        assert_edp_pll_enabled(dev_priv);

        DRM_DEBUG_KMS("disabling eDP PLL\n");

        intel_dp->DP &= ~DP_PLL_ENABLE;

        I915_WRITE(DP_A, intel_dp->DP);
        POSTING_READ(DP_A);
        udelay(200);
}

static bool downstream_hpd_needs_d0(struct intel_dp *intel_dp)
{
        /*
         * DPCD 1.2+ should support BRANCH_DEVICE_CTRL, and thus
         * be capable of signalling downstream hpd with a long pulse.
         * Whether or not that means D3 is safe to use is not clear,
         * but let's assume so until proven otherwise.
         *
         * FIXME should really check all downstream ports...
         */
        return intel_dp->dpcd[DP_DPCD_REV] == 0x11 &&
                intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT &&
                intel_dp->downstream_ports[0] & DP_DS_PORT_HPD;
}

void intel_dp_sink_set_decompression_state(struct intel_dp *intel_dp,
                                           const struct intel_crtc_state *crtc_state,
                                           bool enable)
{
        int ret;

        if (!crtc_state->dsc.compression_enable)
                return;

        ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_DSC_ENABLE,
                                 enable ? DP_DECOMPRESSION_EN : 0);
        if (ret < 0)
                DRM_DEBUG_KMS("Failed to %s sink decompression state\n",
                              enable ? "enable" : "disable");
}

/* If the sink supports it, try to set the power state appropriately */
void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode)
{
        int ret, i;

        /* Should have a valid DPCD by this point */
        if (intel_dp->dpcd[DP_DPCD_REV] < 0x11)
                return;

        if (mode != DRM_MODE_DPMS_ON) {
                if (downstream_hpd_needs_d0(intel_dp))
                        return;

                ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER,
                                         DP_SET_POWER_D3);
        } else {
                struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp);

                /*
                 * When turning on, we need to retry for 1ms to give the sink
                 * time to wake up.
                 */
                for (i = 0; i < 3; i++) {
                        ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER,
                                                 DP_SET_POWER_D0);
                        if (ret == 1)
                                break;
                        msleep(1);
                }

                if (ret == 1 && lspcon->active)
                        lspcon_wait_pcon_mode(lspcon);
        }

        if (ret != 1)
                DRM_DEBUG_KMS("failed to %s sink power state\n",
                              mode == DRM_MODE_DPMS_ON ? "enable" : "disable");
}

static bool cpt_dp_port_selected(struct drm_i915_private *dev_priv,
                                 enum port port, enum pipe *pipe)
{
        enum pipe p;

        for_each_pipe(dev_priv, p) {
                u32 val = I915_READ(TRANS_DP_CTL(p));

                if ((val & TRANS_DP_PORT_SEL_MASK) == TRANS_DP_PORT_SEL(port)) {
                        *pipe = p;
                        return true;
                }
        }

        DRM_DEBUG_KMS("No pipe for DP port %c found\n", port_name(port));

        /* must initialize pipe to something for the asserts */
        *pipe = PIPE_A;

        return false;
}

bool intel_dp_port_enabled(struct drm_i915_private *dev_priv,
                           i915_reg_t dp_reg, enum port port,
                           enum pipe *pipe)
{
        bool ret;
        u32 val;

        val = I915_READ(dp_reg);

        ret = val & DP_PORT_EN;

        /* asserts want to know the pipe even if the port is disabled */
        if (IS_IVYBRIDGE(dev_priv) && port == PORT_A)
                *pipe = (val & DP_PIPE_SEL_MASK_IVB) >> DP_PIPE_SEL_SHIFT_IVB;
        else if (HAS_PCH_CPT(dev_priv) && port != PORT_A)
                ret &= cpt_dp_port_selected(dev_priv, port, pipe);
        else if (IS_CHERRYVIEW(dev_priv))
                *pipe = (val & DP_PIPE_SEL_MASK_CHV) >> DP_PIPE_SEL_SHIFT_CHV;
        else
                *pipe = (val & DP_PIPE_SEL_MASK) >> DP_PIPE_SEL_SHIFT;

        return ret;
}

static bool intel_dp_get_hw_state(struct intel_encoder *encoder,
                                  enum pipe *pipe)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        intel_wakeref_t wakeref;
        bool ret;

        wakeref = intel_display_power_get_if_enabled(dev_priv,
                                                     encoder->power_domain);
        if (!wakeref)
                return false;

        ret = intel_dp_port_enabled(dev_priv, intel_dp->output_reg,
                                    encoder->port, pipe);

        intel_display_power_put(dev_priv, encoder->power_domain, wakeref);

        return ret;
}

static void intel_dp_get_config(struct intel_encoder *encoder,
                                struct intel_crtc_state *pipe_config)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        u32 tmp, flags = 0;
        enum port port = encoder->port;
        struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);

        if (encoder->type == INTEL_OUTPUT_EDP)
                pipe_config->output_types |= BIT(INTEL_OUTPUT_EDP);
        else
                pipe_config->output_types |= BIT(INTEL_OUTPUT_DP);

        tmp = I915_READ(intel_dp->output_reg);

        pipe_config->has_audio = tmp & DP_AUDIO_OUTPUT_ENABLE && port != PORT_A;

        if (HAS_PCH_CPT(dev_priv) && port != PORT_A) {
                u32 trans_dp = I915_READ(TRANS_DP_CTL(crtc->pipe));

                if (trans_dp & TRANS_DP_HSYNC_ACTIVE_HIGH)
                        flags |= DRM_MODE_FLAG_PHSYNC;
                else
                        flags |= DRM_MODE_FLAG_NHSYNC;

                if (trans_dp & TRANS_DP_VSYNC_ACTIVE_HIGH)
                        flags |= DRM_MODE_FLAG_PVSYNC;
                else
                        flags |= DRM_MODE_FLAG_NVSYNC;
        } else {
                if (tmp & DP_SYNC_HS_HIGH)
                        flags |= DRM_MODE_FLAG_PHSYNC;
                else
                        flags |= DRM_MODE_FLAG_NHSYNC;

                if (tmp & DP_SYNC_VS_HIGH)
                        flags |= DRM_MODE_FLAG_PVSYNC;
                else
                        flags |= DRM_MODE_FLAG_NVSYNC;
        }

        pipe_config->base.adjusted_mode.flags |= flags;

        if (IS_G4X(dev_priv) && tmp & DP_COLOR_RANGE_16_235)
                pipe_config->limited_color_range = true;

        pipe_config->lane_count =
                ((tmp & DP_PORT_WIDTH_MASK) >> DP_PORT_WIDTH_SHIFT) + 1;

        intel_dp_get_m_n(crtc, pipe_config);

        if (port == PORT_A) {
                if ((I915_READ(DP_A) & DP_PLL_FREQ_MASK) == DP_PLL_FREQ_162MHZ)
                        pipe_config->port_clock = 162000;
                else
                        pipe_config->port_clock = 270000;
        }

        pipe_config->base.adjusted_mode.crtc_clock =
                intel_dotclock_calculate(pipe_config->port_clock,
                                         &pipe_config->dp_m_n);

        if (intel_dp_is_edp(intel_dp) && dev_priv->vbt.edp.bpp &&
            pipe_config->pipe_bpp > dev_priv->vbt.edp.bpp) {
                /*
                 * This is a big fat ugly hack.
                 *
                 * Some machines in UEFI boot mode provide us a VBT that has 18
                 * bpp and 1.62 GHz link bandwidth for eDP, which for reasons
                 * unknown we fail to light up. Yet the same BIOS boots up with
                 * 24 bpp and 2.7 GHz link. Use the same bpp as the BIOS uses as
                 * max, not what it tells us to use.
                 *
                 * Note: This will still be broken if the eDP panel is not lit
                 * up by the BIOS, and thus we can't get the mode at module
                 * load.
                 */
                DRM_DEBUG_KMS("pipe has %d bpp for eDP panel, overriding BIOS-provided max %d bpp\n",
                              pipe_config->pipe_bpp, dev_priv->vbt.edp.bpp);
                dev_priv->vbt.edp.bpp = pipe_config->pipe_bpp;
        }
}

static void intel_disable_dp(struct intel_encoder *encoder,
                             const struct intel_crtc_state *old_crtc_state,
                             const struct drm_connector_state *old_conn_state)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);

        intel_dp->link_trained = false;

        if (old_crtc_state->has_audio)
                intel_audio_codec_disable(encoder,
                                          old_crtc_state, old_conn_state);

        /* Make sure the panel is off before trying to change the mode. But also
         * ensure that we have vdd while we switch off the panel. */
        intel_edp_panel_vdd_on(intel_dp);
        intel_edp_backlight_off(old_conn_state);
        intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
        intel_edp_panel_off(intel_dp);
}

static void g4x_disable_dp(struct intel_encoder *encoder,
                           const struct intel_crtc_state *old_crtc_state,
                           const struct drm_connector_state *old_conn_state)
{
        intel_disable_dp(encoder, old_crtc_state, old_conn_state);
}

static void vlv_disable_dp(struct intel_encoder *encoder,
                           const struct intel_crtc_state *old_crtc_state,
                           const struct drm_connector_state *old_conn_state)
{
        intel_disable_dp(encoder, old_crtc_state, old_conn_state);
}

static void g4x_post_disable_dp(struct intel_encoder *encoder,
                                const struct intel_crtc_state *old_crtc_state,
                                const struct drm_connector_state *old_conn_state)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        enum port port = encoder->port;

        /*
         * Bspec does not list a specific disable sequence for g4x DP.
         * Follow the ilk+ sequence (disable pipe before the port) for
         * g4x DP as it does not suffer from underruns like the normal
         * g4x modeset sequence (disable pipe after the port).
         */
        intel_dp_link_down(encoder, old_crtc_state);

        /* Only ilk+ has port A */
        if (port == PORT_A)
                ironlake_edp_pll_off(intel_dp, old_crtc_state);
}

static void vlv_post_disable_dp(struct intel_encoder *encoder,
                                const struct intel_crtc_state *old_crtc_state,
                                const struct drm_connector_state *old_conn_state)
{
        intel_dp_link_down(encoder, old_crtc_state);
}

static void chv_post_disable_dp(struct intel_encoder *encoder,
                                const struct intel_crtc_state *old_crtc_state,
                                const struct drm_connector_state *old_conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        intel_dp_link_down(encoder, old_crtc_state);

        vlv_dpio_get(dev_priv);

        /* Assert data lane reset */
        chv_data_lane_soft_reset(encoder, old_crtc_state, true);

        vlv_dpio_put(dev_priv);
}

static void
_intel_dp_set_link_train(struct intel_dp *intel_dp,
                         u32 *DP,
                         u8 dp_train_pat)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        enum port port = intel_dig_port->base.port;
        u8 train_pat_mask = drm_dp_training_pattern_mask(intel_dp->dpcd);

        if (dp_train_pat & train_pat_mask)
                DRM_DEBUG_KMS("Using DP training pattern TPS%d\n",
                              dp_train_pat & train_pat_mask);

        if (HAS_DDI(dev_priv)) {
                u32 temp = I915_READ(intel_dp->regs.dp_tp_ctl);

                if (dp_train_pat & DP_LINK_SCRAMBLING_DISABLE)
                        temp |= DP_TP_CTL_SCRAMBLE_DISABLE;
                else
                        temp &= ~DP_TP_CTL_SCRAMBLE_DISABLE;

                temp &= ~DP_TP_CTL_LINK_TRAIN_MASK;
                switch (dp_train_pat & train_pat_mask) {
                case DP_TRAINING_PATTERN_DISABLE:
                        temp |= DP_TP_CTL_LINK_TRAIN_NORMAL;

                        break;
                case DP_TRAINING_PATTERN_1:
                        temp |= DP_TP_CTL_LINK_TRAIN_PAT1;
                        break;
                case DP_TRAINING_PATTERN_2:
                        temp |= DP_TP_CTL_LINK_TRAIN_PAT2;
                        break;
                case DP_TRAINING_PATTERN_3:
                        temp |= DP_TP_CTL_LINK_TRAIN_PAT3;
                        break;
                case DP_TRAINING_PATTERN_4:
                        temp |= DP_TP_CTL_LINK_TRAIN_PAT4;
                        break;
                }
                I915_WRITE(intel_dp->regs.dp_tp_ctl, temp);

        } else if ((IS_IVYBRIDGE(dev_priv) && port == PORT_A) ||
                   (HAS_PCH_CPT(dev_priv) && port != PORT_A)) {
                *DP &= ~DP_LINK_TRAIN_MASK_CPT;

                switch (dp_train_pat & DP_TRAINING_PATTERN_MASK) {
                case DP_TRAINING_PATTERN_DISABLE:
                        *DP |= DP_LINK_TRAIN_OFF_CPT;
                        break;
                case DP_TRAINING_PATTERN_1:
                        *DP |= DP_LINK_TRAIN_PAT_1_CPT;
                        break;
                case DP_TRAINING_PATTERN_2:
                        *DP |= DP_LINK_TRAIN_PAT_2_CPT;
                        break;
                case DP_TRAINING_PATTERN_3:
                        DRM_DEBUG_KMS("TPS3 not supported, using TPS2 instead\n");
                        *DP |= DP_LINK_TRAIN_PAT_2_CPT;
                        break;
                }

        } else {
                *DP &= ~DP_LINK_TRAIN_MASK;

                switch (dp_train_pat & DP_TRAINING_PATTERN_MASK) {
                case DP_TRAINING_PATTERN_DISABLE:
                        *DP |= DP_LINK_TRAIN_OFF;
                        break;
                case DP_TRAINING_PATTERN_1:
                        *DP |= DP_LINK_TRAIN_PAT_1;
                        break;
                case DP_TRAINING_PATTERN_2:
                        *DP |= DP_LINK_TRAIN_PAT_2;
                        break;
                case DP_TRAINING_PATTERN_3:
                        DRM_DEBUG_KMS("TPS3 not supported, using TPS2 instead\n");
                        *DP |= DP_LINK_TRAIN_PAT_2;
                        break;
                }
        }
}

static void intel_dp_enable_port(struct intel_dp *intel_dp,
                                 const struct intel_crtc_state *old_crtc_state)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        /* enable with pattern 1 (as per spec) */

        intel_dp_program_link_training_pattern(intel_dp, DP_TRAINING_PATTERN_1);

        /*
         * Magic for VLV/CHV. We _must_ first set up the register
         * without actually enabling the port, and then do another
         * write to enable the port. Otherwise link training will
         * fail when the power sequencer is freshly used for this port.
         */
        intel_dp->DP |= DP_PORT_EN;
        if (old_crtc_state->has_audio)
                intel_dp->DP |= DP_AUDIO_OUTPUT_ENABLE;

        I915_WRITE(intel_dp->output_reg, intel_dp->DP);
        POSTING_READ(intel_dp->output_reg);
}

static void intel_enable_dp(struct intel_encoder *encoder,
                            const struct intel_crtc_state *pipe_config,
                            const struct drm_connector_state *conn_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct intel_crtc *crtc = to_intel_crtc(pipe_config->base.crtc);
        u32 dp_reg = I915_READ(intel_dp->output_reg);
        enum pipe pipe = crtc->pipe;
        intel_wakeref_t wakeref;

        if (WARN_ON(dp_reg & DP_PORT_EN))
                return;

        with_pps_lock(intel_dp, wakeref) {
                if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                        vlv_init_panel_power_sequencer(encoder, pipe_config);

                intel_dp_enable_port(intel_dp, pipe_config);

                edp_panel_vdd_on(intel_dp);
                edp_panel_on(intel_dp);
                edp_panel_vdd_off(intel_dp, true);
        }

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                unsigned int lane_mask = 0x0;

                if (IS_CHERRYVIEW(dev_priv))
                        lane_mask = intel_dp_unused_lane_mask(pipe_config->lane_count);

                vlv_wait_port_ready(dev_priv, dp_to_dig_port(intel_dp),
                                    lane_mask);
        }

        intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
        intel_dp_start_link_train(intel_dp);
        intel_dp_stop_link_train(intel_dp);

        if (pipe_config->has_audio) {
                DRM_DEBUG_DRIVER("Enabling DP audio on pipe %c\n",
                                 pipe_name(pipe));
                intel_audio_codec_enable(encoder, pipe_config, conn_state);
        }
}

static void g4x_enable_dp(struct intel_encoder *encoder,
                          const struct intel_crtc_state *pipe_config,
                          const struct drm_connector_state *conn_state)
{
        intel_enable_dp(encoder, pipe_config, conn_state);
        intel_edp_backlight_on(pipe_config, conn_state);
}

static void vlv_enable_dp(struct intel_encoder *encoder,
                          const struct intel_crtc_state *pipe_config,
                          const struct drm_connector_state *conn_state)
{
        intel_edp_backlight_on(pipe_config, conn_state);
}

static void g4x_pre_enable_dp(struct intel_encoder *encoder,
                              const struct intel_crtc_state *pipe_config,
                              const struct drm_connector_state *conn_state)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        enum port port = encoder->port;

        intel_dp_prepare(encoder, pipe_config);

        /* Only ilk+ has port A */
        if (port == PORT_A)
                ironlake_edp_pll_on(intel_dp, pipe_config);
}

static void vlv_detach_power_sequencer(struct intel_dp *intel_dp)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
        enum pipe pipe = intel_dp->pps_pipe;
        i915_reg_t pp_on_reg = PP_ON_DELAYS(pipe);

        WARN_ON(intel_dp->active_pipe != INVALID_PIPE);

        if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B))
                return;

        edp_panel_vdd_off_sync(intel_dp);

        /*
         * VLV seems to get confused when multiple power sequencers
         * have the same port selected (even if only one has power/vdd
         * enabled). The failure manifests as vlv_wait_port_ready() failing
         * CHV on the other hand doesn't seem to mind having the same port
         * selected in multiple power sequencers, but let's clear the
         * port select always when logically disconnecting a power sequencer
         * from a port.
         */
        DRM_DEBUG_KMS("detaching pipe %c power sequencer from [ENCODER:%d:%s]\n",
                      pipe_name(pipe), intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name);
        I915_WRITE(pp_on_reg, 0);
        POSTING_READ(pp_on_reg);

        intel_dp->pps_pipe = INVALID_PIPE;
}

static void vlv_steal_power_sequencer(struct drm_i915_private *dev_priv,
                                      enum pipe pipe)
{
        struct intel_encoder *encoder;

        lockdep_assert_held(&dev_priv->pps_mutex);

        for_each_intel_dp(&dev_priv->drm, encoder) {
                struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);

                WARN(intel_dp->active_pipe == pipe,
                     "stealing pipe %c power sequencer from active [ENCODER:%d:%s]\n",
                     pipe_name(pipe), encoder->base.base.id,
                     encoder->base.name);

                if (intel_dp->pps_pipe != pipe)
                        continue;

                DRM_DEBUG_KMS("stealing pipe %c power sequencer from [ENCODER:%d:%s]\n",
                              pipe_name(pipe), encoder->base.base.id,
                              encoder->base.name);

                /* make sure vdd is off before we steal it */
                vlv_detach_power_sequencer(intel_dp);
        }
}

static void vlv_init_panel_power_sequencer(struct intel_encoder *encoder,
                                           const struct intel_crtc_state *crtc_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);

        lockdep_assert_held(&dev_priv->pps_mutex);

        WARN_ON(intel_dp->active_pipe != INVALID_PIPE);

        if (intel_dp->pps_pipe != INVALID_PIPE &&
            intel_dp->pps_pipe != crtc->pipe) {
                /*
                 * If another power sequencer was being used on this
                 * port previously make sure to turn off vdd there while
                 * we still have control of it.
                 */
                vlv_detach_power_sequencer(intel_dp);
        }

        /*
         * We may be stealing the power
         * sequencer from another port.
         */
        vlv_steal_power_sequencer(dev_priv, crtc->pipe);

        intel_dp->active_pipe = crtc->pipe;

        if (!intel_dp_is_edp(intel_dp))
                return;

        /* now it's all ours */
        intel_dp->pps_pipe = crtc->pipe;

        DRM_DEBUG_KMS("initializing pipe %c power sequencer for [ENCODER:%d:%s]\n",
                      pipe_name(intel_dp->pps_pipe), encoder->base.base.id,
                      encoder->base.name);

        /* init power sequencer on this pipe and port */
        intel_dp_init_panel_power_sequencer(intel_dp);
        intel_dp_init_panel_power_sequencer_registers(intel_dp, true);
}

static void vlv_pre_enable_dp(struct intel_encoder *encoder,
                              const struct intel_crtc_state *pipe_config,
                              const struct drm_connector_state *conn_state)
{
        vlv_phy_pre_encoder_enable(encoder, pipe_config);

        intel_enable_dp(encoder, pipe_config, conn_state);
}

static void vlv_dp_pre_pll_enable(struct intel_encoder *encoder,
                                  const struct intel_crtc_state *pipe_config,
                                  const struct drm_connector_state *conn_state)
{
        intel_dp_prepare(encoder, pipe_config);

        vlv_phy_pre_pll_enable(encoder, pipe_config);
}

static void chv_pre_enable_dp(struct intel_encoder *encoder,
                              const struct intel_crtc_state *pipe_config,
                              const struct drm_connector_state *conn_state)
{
        chv_phy_pre_encoder_enable(encoder, pipe_config);

        intel_enable_dp(encoder, pipe_config, conn_state);

        /* Second common lane will stay alive on its own now */
        chv_phy_release_cl2_override(encoder);
}

static void chv_dp_pre_pll_enable(struct intel_encoder *encoder,
                                  const struct intel_crtc_state *pipe_config,
                                  const struct drm_connector_state *conn_state)
{
        intel_dp_prepare(encoder, pipe_config);

        chv_phy_pre_pll_enable(encoder, pipe_config);
}

static void chv_dp_post_pll_disable(struct intel_encoder *encoder,
                                    const struct intel_crtc_state *old_crtc_state,
                                    const struct drm_connector_state *old_conn_state)
{
        chv_phy_post_pll_disable(encoder, old_crtc_state);
}

/*
 * Fetch AUX CH registers 0x202 - 0x207 which contain
 * link status information
 */
bool
intel_dp_get_link_status(struct intel_dp *intel_dp, u8 link_status[DP_LINK_STATUS_SIZE])
{
        return drm_dp_dpcd_read(&intel_dp->aux, DP_LANE0_1_STATUS, link_status,
                                DP_LINK_STATUS_SIZE) == DP_LINK_STATUS_SIZE;
}

/* These are source-specific values. */
u8
intel_dp_voltage_max(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
        enum port port = encoder->port;

        if (HAS_DDI(dev_priv))
                return intel_ddi_dp_voltage_max(encoder);
        else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
        else if (IS_IVYBRIDGE(dev_priv) && port == PORT_A)
                return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
        else if (HAS_PCH_CPT(dev_priv) && port != PORT_A)
                return DP_TRAIN_VOLTAGE_SWING_LEVEL_3;
        else
                return DP_TRAIN_VOLTAGE_SWING_LEVEL_2;
}

u8
intel_dp_pre_emphasis_max(struct intel_dp *intel_dp, u8 voltage_swing)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
        enum port port = encoder->port;

        if (HAS_DDI(dev_priv)) {
                return intel_ddi_dp_pre_emphasis_max(encoder, voltage_swing);
        } else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        return DP_TRAIN_PRE_EMPH_LEVEL_3;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        return DP_TRAIN_PRE_EMPH_LEVEL_2;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        return DP_TRAIN_PRE_EMPH_LEVEL_1;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
                default:
                        return DP_TRAIN_PRE_EMPH_LEVEL_0;
                }
        } else if (IS_IVYBRIDGE(dev_priv) && port == PORT_A) {
                switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        return DP_TRAIN_PRE_EMPH_LEVEL_2;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        return DP_TRAIN_PRE_EMPH_LEVEL_1;
                default:
                        return DP_TRAIN_PRE_EMPH_LEVEL_0;
                }
        } else {
                switch (voltage_swing & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        return DP_TRAIN_PRE_EMPH_LEVEL_2;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        return DP_TRAIN_PRE_EMPH_LEVEL_2;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        return DP_TRAIN_PRE_EMPH_LEVEL_1;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
                default:
                        return DP_TRAIN_PRE_EMPH_LEVEL_0;
                }
        }
}

static u32 vlv_signal_levels(struct intel_dp *intel_dp)
{
        struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
        unsigned long demph_reg_value, preemph_reg_value,
                uniqtranscale_reg_value;
        u8 train_set = intel_dp->train_set[0];

        switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
        case DP_TRAIN_PRE_EMPH_LEVEL_0:
                preemph_reg_value = 0x0004000;
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        demph_reg_value = 0x2B405555;
                        uniqtranscale_reg_value = 0x552AB83A;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        demph_reg_value = 0x2B404040;
                        uniqtranscale_reg_value = 0x5548B83A;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        demph_reg_value = 0x2B245555;
                        uniqtranscale_reg_value = 0x5560B83A;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
                        demph_reg_value = 0x2B405555;
                        uniqtranscale_reg_value = 0x5598DA3A;
                        break;
                default:
                        return 0;
                }
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_1:
                preemph_reg_value = 0x0002000;
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        demph_reg_value = 0x2B404040;
                        uniqtranscale_reg_value = 0x5552B83A;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        demph_reg_value = 0x2B404848;
                        uniqtranscale_reg_value = 0x5580B83A;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        demph_reg_value = 0x2B404040;
                        uniqtranscale_reg_value = 0x55ADDA3A;
                        break;
                default:
                        return 0;
                }
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_2:
                preemph_reg_value = 0x0000000;
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        demph_reg_value = 0x2B305555;
                        uniqtranscale_reg_value = 0x5570B83A;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        demph_reg_value = 0x2B2B4040;
                        uniqtranscale_reg_value = 0x55ADDA3A;
                        break;
                default:
                        return 0;
                }
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_3:
                preemph_reg_value = 0x0006000;
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        demph_reg_value = 0x1B405555;
                        uniqtranscale_reg_value = 0x55ADDA3A;
                        break;
                default:
                        return 0;
                }
                break;
        default:
                return 0;
        }

        vlv_set_phy_signal_level(encoder, demph_reg_value, preemph_reg_value,
                                 uniqtranscale_reg_value, 0);

        return 0;
}

static u32 chv_signal_levels(struct intel_dp *intel_dp)
{
        struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
        u32 deemph_reg_value, margin_reg_value;
        bool uniq_trans_scale = false;
        u8 train_set = intel_dp->train_set[0];

        switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
        case DP_TRAIN_PRE_EMPH_LEVEL_0:
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        deemph_reg_value = 128;
                        margin_reg_value = 52;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        deemph_reg_value = 128;
                        margin_reg_value = 77;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        deemph_reg_value = 128;
                        margin_reg_value = 102;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
                        deemph_reg_value = 128;
                        margin_reg_value = 154;
                        uniq_trans_scale = true;
                        break;
                default:
                        return 0;
                }
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_1:
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        deemph_reg_value = 85;
                        margin_reg_value = 78;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        deemph_reg_value = 85;
                        margin_reg_value = 116;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                        deemph_reg_value = 85;
                        margin_reg_value = 154;
                        break;
                default:
                        return 0;
                }
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_2:
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        deemph_reg_value = 64;
                        margin_reg_value = 104;
                        break;
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                        deemph_reg_value = 64;
                        margin_reg_value = 154;
                        break;
                default:
                        return 0;
                }
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_3:
                switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
                case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
                        deemph_reg_value = 43;
                        margin_reg_value = 154;
                        break;
                default:
                        return 0;
                }
                break;
        default:
                return 0;
        }

        chv_set_phy_signal_level(encoder, deemph_reg_value,
                                 margin_reg_value, uniq_trans_scale);

        return 0;
}

static u32
g4x_signal_levels(u8 train_set)
{
        u32 signal_levels = 0;

        switch (train_set & DP_TRAIN_VOLTAGE_SWING_MASK) {
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0:
        default:
                signal_levels |= DP_VOLTAGE_0_4;
                break;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_1:
                signal_levels |= DP_VOLTAGE_0_6;
                break;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_2:
                signal_levels |= DP_VOLTAGE_0_8;
                break;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_3:
                signal_levels |= DP_VOLTAGE_1_2;
                break;
        }
        switch (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) {
        case DP_TRAIN_PRE_EMPH_LEVEL_0:
        default:
                signal_levels |= DP_PRE_EMPHASIS_0;
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_1:
                signal_levels |= DP_PRE_EMPHASIS_3_5;
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_2:
                signal_levels |= DP_PRE_EMPHASIS_6;
                break;
        case DP_TRAIN_PRE_EMPH_LEVEL_3:
                signal_levels |= DP_PRE_EMPHASIS_9_5;
                break;
        }
        return signal_levels;
}

/* SNB CPU eDP voltage swing and pre-emphasis control */
static u32
snb_cpu_edp_signal_levels(u8 train_set)
{
        int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
                                         DP_TRAIN_PRE_EMPHASIS_MASK);
        switch (signal_levels) {
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
                return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
                return EDP_LINK_TRAIN_400MV_3_5DB_SNB_B;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_2:
                return EDP_LINK_TRAIN_400_600MV_6DB_SNB_B;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
                return EDP_LINK_TRAIN_600_800MV_3_5DB_SNB_B;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_3 | DP_TRAIN_PRE_EMPH_LEVEL_0:
                return EDP_LINK_TRAIN_800_1200MV_0DB_SNB_B;
        default:
                DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
                              "0x%x\n", signal_levels);
                return EDP_LINK_TRAIN_400_600MV_0DB_SNB_B;
        }
}

/* IVB CPU eDP voltage swing and pre-emphasis control */
static u32
ivb_cpu_edp_signal_levels(u8 train_set)
{
        int signal_levels = train_set & (DP_TRAIN_VOLTAGE_SWING_MASK |
                                         DP_TRAIN_PRE_EMPHASIS_MASK);
        switch (signal_levels) {
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
                return EDP_LINK_TRAIN_400MV_0DB_IVB;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
                return EDP_LINK_TRAIN_400MV_3_5DB_IVB;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
                return EDP_LINK_TRAIN_400MV_6DB_IVB;

        case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
                return EDP_LINK_TRAIN_600MV_0DB_IVB;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
                return EDP_LINK_TRAIN_600MV_3_5DB_IVB;

        case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
                return EDP_LINK_TRAIN_800MV_0DB_IVB;
        case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
                return EDP_LINK_TRAIN_800MV_3_5DB_IVB;

        default:
                DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level:"
                              "0x%x\n", signal_levels);
                return EDP_LINK_TRAIN_500MV_0DB_IVB;
        }
}

void
intel_dp_set_signal_levels(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        enum port port = intel_dig_port->base.port;
        u32 signal_levels, mask = 0;
        u8 train_set = intel_dp->train_set[0];

        if (IS_GEN9_LP(dev_priv) || INTEL_GEN(dev_priv) >= 10) {
                signal_levels = bxt_signal_levels(intel_dp);
        } else if (HAS_DDI(dev_priv)) {
                signal_levels = ddi_signal_levels(intel_dp);
                mask = DDI_BUF_EMP_MASK;
        } else if (IS_CHERRYVIEW(dev_priv)) {
                signal_levels = chv_signal_levels(intel_dp);
        } else if (IS_VALLEYVIEW(dev_priv)) {
                signal_levels = vlv_signal_levels(intel_dp);
        } else if (IS_IVYBRIDGE(dev_priv) && port == PORT_A) {
                signal_levels = ivb_cpu_edp_signal_levels(train_set);
                mask = EDP_LINK_TRAIN_VOL_EMP_MASK_IVB;
        } else if (IS_GEN(dev_priv, 6) && port == PORT_A) {
                signal_levels = snb_cpu_edp_signal_levels(train_set);
                mask = EDP_LINK_TRAIN_VOL_EMP_MASK_SNB;
        } else {
                signal_levels = g4x_signal_levels(train_set);
                mask = DP_VOLTAGE_MASK | DP_PRE_EMPHASIS_MASK;
        }

        if (mask)
                DRM_DEBUG_KMS("Using signal levels %08x\n", signal_levels);

        DRM_DEBUG_KMS("Using vswing level %d\n",
                train_set & DP_TRAIN_VOLTAGE_SWING_MASK);
        DRM_DEBUG_KMS("Using pre-emphasis level %d\n",
                (train_set & DP_TRAIN_PRE_EMPHASIS_MASK) >>
                        DP_TRAIN_PRE_EMPHASIS_SHIFT);

        intel_dp->DP = (intel_dp->DP & ~mask) | signal_levels;

        I915_WRITE(intel_dp->output_reg, intel_dp->DP);
        POSTING_READ(intel_dp->output_reg);
}

void
intel_dp_program_link_training_pattern(struct intel_dp *intel_dp,
                                       u8 dp_train_pat)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct drm_i915_private *dev_priv =
                to_i915(intel_dig_port->base.base.dev);

        _intel_dp_set_link_train(intel_dp, &intel_dp->DP, dp_train_pat);

        I915_WRITE(intel_dp->output_reg, intel_dp->DP);
        POSTING_READ(intel_dp->output_reg);
}

void intel_dp_set_idle_link_train(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        enum port port = intel_dig_port->base.port;
        u32 val;

        if (!HAS_DDI(dev_priv))
                return;

        val = I915_READ(intel_dp->regs.dp_tp_ctl);
        val &= ~DP_TP_CTL_LINK_TRAIN_MASK;
        val |= DP_TP_CTL_LINK_TRAIN_IDLE;
        I915_WRITE(intel_dp->regs.dp_tp_ctl, val);

        /*
         * Until TGL on PORT_A we can have only eDP in SST mode. There the only
         * reason we need to set idle transmission mode is to work around a HW
         * issue where we enable the pipe while not in idle link-training mode.
         * In this case there is requirement to wait for a minimum number of
         * idle patterns to be sent.
         */
        if (port == PORT_A && INTEL_GEN(dev_priv) < 12)
                return;

        if (intel_de_wait_for_set(dev_priv, intel_dp->regs.dp_tp_status,
                                  DP_TP_STATUS_IDLE_DONE, 1))
                DRM_ERROR("Timed out waiting for DP idle patterns\n");
}

static void
intel_dp_link_down(struct intel_encoder *encoder,
                   const struct intel_crtc_state *old_crtc_state)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct intel_crtc *crtc = to_intel_crtc(old_crtc_state->base.crtc);
        enum port port = encoder->port;
        u32 DP = intel_dp->DP;

        if (WARN_ON((I915_READ(intel_dp->output_reg) & DP_PORT_EN) == 0))
                return;

        DRM_DEBUG_KMS("\n");

        if ((IS_IVYBRIDGE(dev_priv) && port == PORT_A) ||
            (HAS_PCH_CPT(dev_priv) && port != PORT_A)) {
                DP &= ~DP_LINK_TRAIN_MASK_CPT;
                DP |= DP_LINK_TRAIN_PAT_IDLE_CPT;
        } else {
                DP &= ~DP_LINK_TRAIN_MASK;
                DP |= DP_LINK_TRAIN_PAT_IDLE;
        }
        I915_WRITE(intel_dp->output_reg, DP);
        POSTING_READ(intel_dp->output_reg);

        DP &= ~(DP_PORT_EN | DP_AUDIO_OUTPUT_ENABLE);
        I915_WRITE(intel_dp->output_reg, DP);
        POSTING_READ(intel_dp->output_reg);

        /*
         * HW workaround for IBX, we need to move the port
         * to transcoder A after disabling it to allow the
         * matching HDMI port to be enabled on transcoder A.
         */
        if (HAS_PCH_IBX(dev_priv) && crtc->pipe == PIPE_B && port != PORT_A) {
                /*
                 * We get CPU/PCH FIFO underruns on the other pipe when
                 * doing the workaround. Sweep them under the rug.
                 */
                intel_set_cpu_fifo_underrun_reporting(dev_priv, PIPE_A, false);
                intel_set_pch_fifo_underrun_reporting(dev_priv, PIPE_A, false);

                /* always enable with pattern 1 (as per spec) */
                DP &= ~(DP_PIPE_SEL_MASK | DP_LINK_TRAIN_MASK);
                DP |= DP_PORT_EN | DP_PIPE_SEL(PIPE_A) |
                        DP_LINK_TRAIN_PAT_1;
                I915_WRITE(intel_dp->output_reg, DP);
                POSTING_READ(intel_dp->output_reg);

                DP &= ~DP_PORT_EN;
                I915_WRITE(intel_dp->output_reg, DP);
                POSTING_READ(intel_dp->output_reg);

                intel_wait_for_vblank_if_active(dev_priv, PIPE_A);
                intel_set_cpu_fifo_underrun_reporting(dev_priv, PIPE_A, true);
                intel_set_pch_fifo_underrun_reporting(dev_priv, PIPE_A, true);
        }

        msleep(intel_dp->panel_power_down_delay);

        intel_dp->DP = DP;

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                intel_wakeref_t wakeref;

                with_pps_lock(intel_dp, wakeref)
                        intel_dp->active_pipe = INVALID_PIPE;
        }
}

static void
intel_dp_extended_receiver_capabilities(struct intel_dp *intel_dp)
{
        u8 dpcd_ext[6];

        /*
         * Prior to DP1.3 the bit represented by
         * DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT was reserved.
         * if it is set DP_DPCD_REV at 0000h could be at a value less than
         * the true capability of the panel. The only way to check is to
         * then compare 0000h and 2200h.
         */
        if (!(intel_dp->dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
              DP_EXTENDED_RECEIVER_CAP_FIELD_PRESENT))
                return;

        if (drm_dp_dpcd_read(&intel_dp->aux, DP_DP13_DPCD_REV,
                             &dpcd_ext, sizeof(dpcd_ext)) != sizeof(dpcd_ext)) {
                DRM_ERROR("DPCD failed read at extended capabilities\n");
                return;
        }

        if (intel_dp->dpcd[DP_DPCD_REV] > dpcd_ext[DP_DPCD_REV]) {
                DRM_DEBUG_KMS("DPCD extended DPCD rev less than base DPCD rev\n");
                return;
        }

        if (!memcmp(intel_dp->dpcd, dpcd_ext, sizeof(dpcd_ext)))
                return;

        DRM_DEBUG_KMS("Base DPCD: %*ph\n",
                      (int)sizeof(intel_dp->dpcd), intel_dp->dpcd);

        memcpy(intel_dp->dpcd, dpcd_ext, sizeof(dpcd_ext));
}

bool
intel_dp_read_dpcd(struct intel_dp *intel_dp)
{
        if (drm_dp_dpcd_read(&intel_dp->aux, 0x000, intel_dp->dpcd,
                             sizeof(intel_dp->dpcd)) < 0)
                return false; /* aux transfer failed */

        intel_dp_extended_receiver_capabilities(intel_dp);

        DRM_DEBUG_KMS("DPCD: %*ph\n", (int) sizeof(intel_dp->dpcd), intel_dp->dpcd);

        return intel_dp->dpcd[DP_DPCD_REV] != 0;
}

bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp)
{
        u8 dprx = 0;

        if (drm_dp_dpcd_readb(&intel_dp->aux, DP_DPRX_FEATURE_ENUMERATION_LIST,
                              &dprx) != 1)
                return false;
        return dprx & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED;
}

static void intel_dp_get_dsc_sink_cap(struct intel_dp *intel_dp)
{
        /*
         * Clear the cached register set to avoid using stale values
         * for the sinks that do not support DSC.
         */
        memset(intel_dp->dsc_dpcd, 0, sizeof(intel_dp->dsc_dpcd));

        /* Clear fec_capable to avoid using stale values */
        intel_dp->fec_capable = 0;

        /* Cache the DSC DPCD if eDP or DP rev >= 1.4 */
        if (intel_dp->dpcd[DP_DPCD_REV] >= 0x14 ||
            intel_dp->edp_dpcd[0] >= DP_EDP_14) {
                if (drm_dp_dpcd_read(&intel_dp->aux, DP_DSC_SUPPORT,
                                     intel_dp->dsc_dpcd,
                                     sizeof(intel_dp->dsc_dpcd)) < 0)
                        DRM_ERROR("Failed to read DPCD register 0x%x\n",
                                  DP_DSC_SUPPORT);

                DRM_DEBUG_KMS("DSC DPCD: %*ph\n",
                              (int)sizeof(intel_dp->dsc_dpcd),
                              intel_dp->dsc_dpcd);

                /* FEC is supported only on DP 1.4 */
                if (!intel_dp_is_edp(intel_dp) &&
                    drm_dp_dpcd_readb(&intel_dp->aux, DP_FEC_CAPABILITY,
                                      &intel_dp->fec_capable) < 0)
                        DRM_ERROR("Failed to read FEC DPCD register\n");

                DRM_DEBUG_KMS("FEC CAPABILITY: %x\n", intel_dp->fec_capable);
        }
}

static bool
intel_edp_init_dpcd(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv =
                to_i915(dp_to_dig_port(intel_dp)->base.base.dev);

        /* this function is meant to be called only once */
        WARN_ON(intel_dp->dpcd[DP_DPCD_REV] != 0);

        if (!intel_dp_read_dpcd(intel_dp))
                return false;

        drm_dp_read_desc(&intel_dp->aux, &intel_dp->desc,
                         drm_dp_is_branch(intel_dp->dpcd));

        /*
         * Read the eDP display control registers.
         *
         * Do this independent of DP_DPCD_DISPLAY_CONTROL_CAPABLE bit in
         * DP_EDP_CONFIGURATION_CAP, because some buggy displays do not have it
         * set, but require eDP 1.4+ detection (e.g. for supported link rates
         * method). The display control registers should read zero if they're
         * not supported anyway.
         */
        if (drm_dp_dpcd_read(&intel_dp->aux, DP_EDP_DPCD_REV,
                             intel_dp->edp_dpcd, sizeof(intel_dp->edp_dpcd)) ==
                             sizeof(intel_dp->edp_dpcd))
                DRM_DEBUG_KMS("eDP DPCD: %*ph\n", (int) sizeof(intel_dp->edp_dpcd),
                              intel_dp->edp_dpcd);

        /*
         * This has to be called after intel_dp->edp_dpcd is filled, PSR checks
         * for SET_POWER_CAPABLE bit in intel_dp->edp_dpcd[1]
         */
        intel_psr_init_dpcd(intel_dp);

        /* Read the eDP 1.4+ supported link rates. */
        if (intel_dp->edp_dpcd[0] >= DP_EDP_14) {
                __le16 sink_rates[DP_MAX_SUPPORTED_RATES];
                int i;

                drm_dp_dpcd_read(&intel_dp->aux, DP_SUPPORTED_LINK_RATES,
                                sink_rates, sizeof(sink_rates));

                for (i = 0; i < ARRAY_SIZE(sink_rates); i++) {
                        int val = le16_to_cpu(sink_rates[i]);

                        if (val == 0)
                                break;

                        /* Value read multiplied by 200kHz gives the per-lane
                         * link rate in kHz. The source rates are, however,
                         * stored in terms of LS_Clk kHz. The full conversion
                         * back to symbols is
                         * (val * 200kHz)*(8/10 ch. encoding)*(1/8 bit to Byte)
                         */
                        intel_dp->sink_rates[i] = (val * 200) / 10;
                }
                intel_dp->num_sink_rates = i;
        }

        /*
         * Use DP_LINK_RATE_SET if DP_SUPPORTED_LINK_RATES are available,
         * default to DP_MAX_LINK_RATE and DP_LINK_BW_SET otherwise.
         */
        if (intel_dp->num_sink_rates)
                intel_dp->use_rate_select = true;
        else
                intel_dp_set_sink_rates(intel_dp);

        intel_dp_set_common_rates(intel_dp);

        /* Read the eDP DSC DPCD registers */
        if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
                intel_dp_get_dsc_sink_cap(intel_dp);

        return true;
}


static bool
intel_dp_get_dpcd(struct intel_dp *intel_dp)
{
        if (!intel_dp_read_dpcd(intel_dp))
                return false;

        /*
         * Don't clobber cached eDP rates. Also skip re-reading
         * the OUI/ID since we know it won't change.
         */
        if (!intel_dp_is_edp(intel_dp)) {
                drm_dp_read_desc(&intel_dp->aux, &intel_dp->desc,
                                 drm_dp_is_branch(intel_dp->dpcd));

                intel_dp_set_sink_rates(intel_dp);
                intel_dp_set_common_rates(intel_dp);
        }

        /*
         * Some eDP panels do not set a valid value for sink count, that is why
         * it don't care about read it here and in intel_edp_init_dpcd().
         */
        if (!intel_dp_is_edp(intel_dp) &&
            !drm_dp_has_quirk(&intel_dp->desc, DP_DPCD_QUIRK_NO_SINK_COUNT)) {
                u8 count;
                ssize_t r;

                r = drm_dp_dpcd_readb(&intel_dp->aux, DP_SINK_COUNT, &count);
                if (r < 1)
                        return false;

                /*
                 * Sink count can change between short pulse hpd hence
                 * a member variable in intel_dp will track any changes
                 * between short pulse interrupts.
                 */
                intel_dp->sink_count = DP_GET_SINK_COUNT(count);

                /*
                 * SINK_COUNT == 0 and DOWNSTREAM_PORT_PRESENT == 1 implies that
                 * a dongle is present but no display. Unless we require to know
                 * if a dongle is present or not, we don't need to update
                 * downstream port information. So, an early return here saves
                 * time from performing other operations which are not required.
                 */
                if (!intel_dp->sink_count)
                        return false;
        }

        if (!drm_dp_is_branch(intel_dp->dpcd))
                return true; /* native DP sink */

        if (intel_dp->dpcd[DP_DPCD_REV] == 0x10)
                return true; /* no per-port downstream info */

        if (drm_dp_dpcd_read(&intel_dp->aux, DP_DOWNSTREAM_PORT_0,
                             intel_dp->downstream_ports,
                             DP_MAX_DOWNSTREAM_PORTS) < 0)
                return false; /* downstream port status fetch failed */

        return true;
}

static bool
intel_dp_sink_can_mst(struct intel_dp *intel_dp)
{
        u8 mstm_cap;

        if (intel_dp->dpcd[DP_DPCD_REV] < 0x12)
                return false;

        if (drm_dp_dpcd_readb(&intel_dp->aux, DP_MSTM_CAP, &mstm_cap) != 1)
                return false;

        return mstm_cap & DP_MST_CAP;
}

static bool
intel_dp_can_mst(struct intel_dp *intel_dp)
{
        return i915_modparams.enable_dp_mst &&
                intel_dp->can_mst &&
                intel_dp_sink_can_mst(intel_dp);
}

static void
intel_dp_configure_mst(struct intel_dp *intel_dp)
{
        struct intel_encoder *encoder =
                &dp_to_dig_port(intel_dp)->base;
        bool sink_can_mst = intel_dp_sink_can_mst(intel_dp);

        DRM_DEBUG_KMS("[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam: %s\n",
                      encoder->base.base.id, encoder->base.name,
                      yesno(intel_dp->can_mst), yesno(sink_can_mst),
                      yesno(i915_modparams.enable_dp_mst));

        if (!intel_dp->can_mst)
                return;

        intel_dp->is_mst = sink_can_mst &&
                i915_modparams.enable_dp_mst;

        drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
                                        intel_dp->is_mst);
}

static bool
intel_dp_get_sink_irq_esi(struct intel_dp *intel_dp, u8 *sink_irq_vector)
{
        return drm_dp_dpcd_read(&intel_dp->aux, DP_SINK_COUNT_ESI,
                                sink_irq_vector, DP_DPRX_ESI_LEN) ==
                DP_DPRX_ESI_LEN;
}

bool
intel_dp_needs_vsc_sdp(const struct intel_crtc_state *crtc_state,
                       const struct drm_connector_state *conn_state)
{
        /*
         * As per DP 1.4a spec section 2.2.4.3 [MSA Field for Indication
         * of Color Encoding Format and Content Color Gamut], in order to
         * sending YCBCR 420 or HDR BT.2020 signals we should use DP VSC SDP.
         */
        if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420)
                return true;

        switch (conn_state->colorspace) {
        case DRM_MODE_COLORIMETRY_SYCC_601:
        case DRM_MODE_COLORIMETRY_OPYCC_601:
        case DRM_MODE_COLORIMETRY_BT2020_YCC:
        case DRM_MODE_COLORIMETRY_BT2020_RGB:
        case DRM_MODE_COLORIMETRY_BT2020_CYCC:
                return true;
        default:
                break;
        }

        return false;
}

static void
intel_dp_setup_vsc_sdp(struct intel_dp *intel_dp,
                       const struct intel_crtc_state *crtc_state,
                       const struct drm_connector_state *conn_state)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct dp_sdp vsc_sdp = {};

        /* Prepare VSC Header for SU as per DP 1.4a spec, Table 2-119 */
        vsc_sdp.sdp_header.HB0 = 0;
        vsc_sdp.sdp_header.HB1 = 0x7;

        /*
         * VSC SDP supporting 3D stereo, PSR2, and Pixel Encoding/
         * Colorimetry Format indication.
         */
        vsc_sdp.sdp_header.HB2 = 0x5;

        /*
         * VSC SDP supporting 3D stereo, + PSR2, + Pixel Encoding/
         * Colorimetry Format indication (HB2 = 05h).
         */
        vsc_sdp.sdp_header.HB3 = 0x13;

        /* DP 1.4a spec, Table 2-120 */
        switch (crtc_state->output_format) {
        case INTEL_OUTPUT_FORMAT_YCBCR444:
                vsc_sdp.db[16] = 0x1 << 4; /* YCbCr 444 : DB16[7:4] = 1h */
                break;
        case INTEL_OUTPUT_FORMAT_YCBCR420:
                vsc_sdp.db[16] = 0x3 << 4; /* YCbCr 420 : DB16[7:4] = 3h */
                break;
        case INTEL_OUTPUT_FORMAT_RGB:
        default:
                /* RGB: DB16[7:4] = 0h */
                break;
        }

        switch (conn_state->colorspace) {
        case DRM_MODE_COLORIMETRY_BT709_YCC:
                vsc_sdp.db[16] |= 0x1;
                break;
        case DRM_MODE_COLORIMETRY_XVYCC_601:
                vsc_sdp.db[16] |= 0x2;
                break;
        case DRM_MODE_COLORIMETRY_XVYCC_709:
                vsc_sdp.db[16] |= 0x3;
                break;
        case DRM_MODE_COLORIMETRY_SYCC_601:
                vsc_sdp.db[16] |= 0x4;
                break;
        case DRM_MODE_COLORIMETRY_OPYCC_601:
                vsc_sdp.db[16] |= 0x5;
                break;
        case DRM_MODE_COLORIMETRY_BT2020_CYCC:
        case DRM_MODE_COLORIMETRY_BT2020_RGB:
                vsc_sdp.db[16] |= 0x6;
                break;
        case DRM_MODE_COLORIMETRY_BT2020_YCC:
                vsc_sdp.db[16] |= 0x7;
                break;
        case DRM_MODE_COLORIMETRY_DCI_P3_RGB_D65:
        case DRM_MODE_COLORIMETRY_DCI_P3_RGB_THEATER:
                vsc_sdp.db[16] |= 0x4; /* DCI-P3 (SMPTE RP 431-2) */
                break;
        default:
                /* sRGB (IEC 61966-2-1) / ITU-R BT.601: DB16[0:3] = 0h */

                /* RGB->YCBCR color conversion uses the BT.709 color space. */
                if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420)
                        vsc_sdp.db[16] |= 0x1; /* 0x1, ITU-R BT.709 */
                break;
        }

        /*
         * For pixel encoding formats YCbCr444, YCbCr422, YCbCr420, and Y Only,
         * the following Component Bit Depth values are defined:
         * 001b = 8bpc.
         * 010b = 10bpc.
         * 011b = 12bpc.
         * 100b = 16bpc.
         */
        switch (crtc_state->pipe_bpp) {
        case 24: /* 8bpc */
                vsc_sdp.db[17] = 0x1;
                break;
        case 30: /* 10bpc */
                vsc_sdp.db[17] = 0x2;
                break;
        case 36: /* 12bpc */
                vsc_sdp.db[17] = 0x3;
                break;
        case 48: /* 16bpc */
                vsc_sdp.db[17] = 0x4;
                break;
        default:
                MISSING_CASE(crtc_state->pipe_bpp);
                break;
        }

        /*
         * Dynamic Range (Bit 7)
         * 0 = VESA range, 1 = CTA range.
         * all YCbCr are always limited range
         */
        vsc_sdp.db[17] |= 0x80;

        /*
         * Content Type (Bits 2:0)
         * 000b = Not defined.
         * 001b = Graphics.
         * 010b = Photo.
         * 011b = Video.
         * 100b = Game
         * All other values are RESERVED.
         * Note: See CTA-861-G for the definition and expected
         * processing by a stream sink for the above contect types.
         */
        vsc_sdp.db[18] = 0;

        intel_dig_port->write_infoframe(&intel_dig_port->base,
                        crtc_state, DP_SDP_VSC, &vsc_sdp, sizeof(vsc_sdp));
}

static void
intel_dp_setup_hdr_metadata_infoframe_sdp(struct intel_dp *intel_dp,
                                          const struct intel_crtc_state *crtc_state,
                                          const struct drm_connector_state *conn_state)
{
        struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
        struct dp_sdp infoframe_sdp = {};
        struct hdmi_drm_infoframe drm_infoframe = {};
        const int infoframe_size = HDMI_INFOFRAME_HEADER_SIZE + HDMI_DRM_INFOFRAME_SIZE;
        unsigned char buf[HDMI_INFOFRAME_HEADER_SIZE + HDMI_DRM_INFOFRAME_SIZE];
        ssize_t len;
        int ret;

        ret = drm_hdmi_infoframe_set_hdr_metadata(&drm_infoframe, conn_state);
        if (ret) {
                DRM_DEBUG_KMS("couldn't set HDR metadata in infoframe\n");
                return;
        }

        len = hdmi_drm_infoframe_pack_only(&drm_infoframe, buf, sizeof(buf));
        if (len < 0) {
                DRM_DEBUG_KMS("buffer size is smaller than hdr metadata infoframe\n");
                return;
        }

        if (len != infoframe_size) {
                DRM_DEBUG_KMS("wrong static hdr metadata size\n");
                return;
        }

        /*
         * Set up the infoframe sdp packet for HDR static metadata.
         * Prepare VSC Header for SU as per DP 1.4a spec,
         * Table 2-100 and Table 2-101
         */

        /* Packet ID, 00h for non-Audio INFOFRAME */
        infoframe_sdp.sdp_header.HB0 = 0;
        /*
         * Packet Type 80h + Non-audio INFOFRAME Type value
         * HDMI_INFOFRAME_TYPE_DRM: 0x87,
         */
        infoframe_sdp.sdp_header.HB1 = drm_infoframe.type;
        /*
         * Least Significant Eight Bits of (Data Byte Count – 1)
         * infoframe_size - 1,
         */
        infoframe_sdp.sdp_header.HB2 = 0x1D;
        /* INFOFRAME SDP Version Number */
        infoframe_sdp.sdp_header.HB3 = (0x13 << 2);
        /* CTA Header Byte 2 (INFOFRAME Version Number) */
        infoframe_sdp.db[0] = drm_infoframe.version;
        /* CTA Header Byte 3 (Length of INFOFRAME): HDMI_DRM_INFOFRAME_SIZE */
        infoframe_sdp.db[1] = drm_infoframe.length;
        /*
         * Copy HDMI_DRM_INFOFRAME_SIZE size from a buffer after
         * HDMI_INFOFRAME_HEADER_SIZE
         */
        BUILD_BUG_ON(sizeof(infoframe_sdp.db) < HDMI_DRM_INFOFRAME_SIZE + 2);
        memcpy(&infoframe_sdp.db[2], &buf[HDMI_INFOFRAME_HEADER_SIZE],
               HDMI_DRM_INFOFRAME_SIZE);

        /*
         * Size of DP infoframe sdp packet for HDR static metadata is consist of
         * - DP SDP Header(struct dp_sdp_header): 4 bytes
         * - Two Data Blocks: 2 bytes
         *    CTA Header Byte2 (INFOFRAME Version Number)
         *    CTA Header Byte3 (Length of INFOFRAME)
         * - HDMI_DRM_INFOFRAME_SIZE: 26 bytes
         *
         * Prior to GEN11's GMP register size is identical to DP HDR static metadata
         * infoframe size. But GEN11+ has larger than that size, write_infoframe
         * will pad rest of the size.
         */
        intel_dig_port->write_infoframe(&intel_dig_port->base, crtc_state,
                                        HDMI_PACKET_TYPE_GAMUT_METADATA,
                                        &infoframe_sdp,
                                        sizeof(struct dp_sdp_header) + 2 + HDMI_DRM_INFOFRAME_SIZE);
}

void intel_dp_vsc_enable(struct intel_dp *intel_dp,
                         const struct intel_crtc_state *crtc_state,
                         const struct drm_connector_state *conn_state)
{
        if (!intel_dp_needs_vsc_sdp(crtc_state, conn_state))
                return;

        intel_dp_setup_vsc_sdp(intel_dp, crtc_state, conn_state);
}

void intel_dp_hdr_metadata_enable(struct intel_dp *intel_dp,
                                  const struct intel_crtc_state *crtc_state,
                                  const struct drm_connector_state *conn_state)
{
        if (!conn_state->hdr_output_metadata)
                return;

        intel_dp_setup_hdr_metadata_infoframe_sdp(intel_dp,
                                                  crtc_state,
                                                  conn_state);
}

static u8 intel_dp_autotest_link_training(struct intel_dp *intel_dp)
{
        int status = 0;
        int test_link_rate;
        u8 test_lane_count, test_link_bw;
        /* (DP CTS 1.2)
         * 4.3.1.11
         */
        /* Read the TEST_LANE_COUNT and TEST_LINK_RTAE fields (DP CTS 3.1.4) */
        status = drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_LANE_COUNT,
                                   &test_lane_count);

        if (status <= 0) {
                DRM_DEBUG_KMS("Lane count read failed\n");
                return DP_TEST_NAK;
        }
        test_lane_count &= DP_MAX_LANE_COUNT_MASK;

        status = drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_LINK_RATE,
                                   &test_link_bw);
        if (status <= 0) {
                DRM_DEBUG_KMS("Link Rate read failed\n");
                return DP_TEST_NAK;
        }
        test_link_rate = drm_dp_bw_code_to_link_rate(test_link_bw);

        /* Validate the requested link rate and lane count */
        if (!intel_dp_link_params_valid(intel_dp, test_link_rate,
                                        test_lane_count))
                return DP_TEST_NAK;

        intel_dp->compliance.test_lane_count = test_lane_count;
        intel_dp->compliance.test_link_rate = test_link_rate;

        return DP_TEST_ACK;
}

static u8 intel_dp_autotest_video_pattern(struct intel_dp *intel_dp)
{
        u8 test_pattern;
        u8 test_misc;
        __be16 h_width, v_height;
        int status = 0;

        /* Read the TEST_PATTERN (DP CTS 3.1.5) */
        status = drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_PATTERN,
                                   &test_pattern);
        if (status <= 0) {
                DRM_DEBUG_KMS("Test pattern read failed\n");
                return DP_TEST_NAK;
        }
        if (test_pattern != DP_COLOR_RAMP)
                return DP_TEST_NAK;

        status = drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_H_WIDTH_HI,
                                  &h_width, 2);
        if (status <= 0) {
                DRM_DEBUG_KMS("H Width read failed\n");
                return DP_TEST_NAK;
        }

        status = drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_V_HEIGHT_HI,
                                  &v_height, 2);
        if (status <= 0) {
                DRM_DEBUG_KMS("V Height read failed\n");
                return DP_TEST_NAK;
        }

        status = drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_MISC0,
                                   &test_misc);
        if (status <= 0) {
                DRM_DEBUG_KMS("TEST MISC read failed\n");
                return DP_TEST_NAK;
        }
        if ((test_misc & DP_TEST_COLOR_FORMAT_MASK) != DP_COLOR_FORMAT_RGB)
                return DP_TEST_NAK;
        if (test_misc & DP_TEST_DYNAMIC_RANGE_CEA)
                return DP_TEST_NAK;
        switch (test_misc & DP_TEST_BIT_DEPTH_MASK) {
        case DP_TEST_BIT_DEPTH_6:
                intel_dp->compliance.test_data.bpc = 6;
                break;
        case DP_TEST_BIT_DEPTH_8:
                intel_dp->compliance.test_data.bpc = 8;
                break;
        default:
                return DP_TEST_NAK;
        }

        intel_dp->compliance.test_data.video_pattern = test_pattern;
        intel_dp->compliance.test_data.hdisplay = be16_to_cpu(h_width);
        intel_dp->compliance.test_data.vdisplay = be16_to_cpu(v_height);
        /* Set test active flag here so userspace doesn't interrupt things */
        intel_dp->compliance.test_active = 1;

        return DP_TEST_ACK;
}

static u8 intel_dp_autotest_edid(struct intel_dp *intel_dp)
{
        u8 test_result = DP_TEST_ACK;
        struct intel_connector *intel_connector = intel_dp->attached_connector;
        struct drm_connector *connector = &intel_connector->base;

        if (intel_connector->detect_edid == NULL ||
            connector->edid_corrupt ||
            intel_dp->aux.i2c_defer_count > 6) {
                /* Check EDID read for NACKs, DEFERs and corruption
                 * (DP CTS 1.2 Core r1.1)
                 *    4.2.2.4 : Failed EDID read, I2C_NAK
                 *    4.2.2.5 : Failed EDID read, I2C_DEFER
                 *    4.2.2.6 : EDID corruption detected
                 * Use failsafe mode for all cases
                 */
                if (intel_dp->aux.i2c_nack_count > 0 ||
                        intel_dp->aux.i2c_defer_count > 0)
                        DRM_DEBUG_KMS("EDID read had %d NACKs, %d DEFERs\n",
                                      intel_dp->aux.i2c_nack_count,
                                      intel_dp->aux.i2c_defer_count);
                intel_dp->compliance.test_data.edid = INTEL_DP_RESOLUTION_FAILSAFE;
        } else {
                struct edid *block = intel_connector->detect_edid;

                /* We have to write the checksum
                 * of the last block read
                 */
                block += intel_connector->detect_edid->extensions;

                if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_EDID_CHECKSUM,
                                       block->checksum) <= 0)
                        DRM_DEBUG_KMS("Failed to write EDID checksum\n");

                test_result = DP_TEST_ACK | DP_TEST_EDID_CHECKSUM_WRITE;
                intel_dp->compliance.test_data.edid = INTEL_DP_RESOLUTION_PREFERRED;
        }

        /* Set test active flag here so userspace doesn't interrupt things */
        intel_dp->compliance.test_active = 1;

        return test_result;
}

static u8 intel_dp_autotest_phy_pattern(struct intel_dp *intel_dp)
{
        u8 test_result = DP_TEST_NAK;
        return test_result;
}

static void intel_dp_handle_test_request(struct intel_dp *intel_dp)
{
        u8 response = DP_TEST_NAK;
        u8 request = 0;
        int status;

        status = drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_REQUEST, &request);
        if (status <= 0) {
                DRM_DEBUG_KMS("Could not read test request from sink\n");
                goto update_status;
        }

        switch (request) {
        case DP_TEST_LINK_TRAINING:
                DRM_DEBUG_KMS("LINK_TRAINING test requested\n");
                response = intel_dp_autotest_link_training(intel_dp);
                break;
        case DP_TEST_LINK_VIDEO_PATTERN:
                DRM_DEBUG_KMS("TEST_PATTERN test requested\n");
                response = intel_dp_autotest_video_pattern(intel_dp);
                break;
        case DP_TEST_LINK_EDID_READ:
                DRM_DEBUG_KMS("EDID test requested\n");
                response = intel_dp_autotest_edid(intel_dp);
                break;
        case DP_TEST_LINK_PHY_TEST_PATTERN:
                DRM_DEBUG_KMS("PHY_PATTERN test requested\n");
                response = intel_dp_autotest_phy_pattern(intel_dp);
                break;
        default:
                DRM_DEBUG_KMS("Invalid test request '%02x'\n", request);
                break;
        }

        if (response & DP_TEST_ACK)
                intel_dp->compliance.test_type = request;

update_status:
        status = drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_RESPONSE, response);
        if (status <= 0)
                DRM_DEBUG_KMS("Could not write test response to sink\n");
}

static int
intel_dp_check_mst_status(struct intel_dp *intel_dp)
{
        bool bret;

        if (intel_dp->is_mst) {
                u8 esi[DP_DPRX_ESI_LEN] = { 0 };
                int ret = 0;
                int retry;
                bool handled;

                WARN_ON_ONCE(intel_dp->active_mst_links < 0);
                bret = intel_dp_get_sink_irq_esi(intel_dp, esi);
go_again:
                if (bret == true) {

                        /* check link status - esi[10] = 0x200c */
                        if (intel_dp->active_mst_links > 0 &&
                            !drm_dp_channel_eq_ok(&esi[10], intel_dp->lane_count)) {
                                DRM_DEBUG_KMS("channel EQ not ok, retraining\n");
                                intel_dp_start_link_train(intel_dp);
                                intel_dp_stop_link_train(intel_dp);
                        }

                        DRM_DEBUG_KMS("got esi %3ph\n", esi);
                        ret = drm_dp_mst_hpd_irq(&intel_dp->mst_mgr, esi, &handled);

                        if (handled) {
                                for (retry = 0; retry < 3; retry++) {
                                        int wret;
                                        wret = drm_dp_dpcd_write(&intel_dp->aux,
                                                                 DP_SINK_COUNT_ESI+1,
                                                                 &esi[1], 3);
                                        if (wret == 3) {
                                                break;
                                        }
                                }

                                bret = intel_dp_get_sink_irq_esi(intel_dp, esi);
                                if (bret == true) {
                                        DRM_DEBUG_KMS("got esi2 %3ph\n", esi);
                                        goto go_again;
                                }
                        } else
                                ret = 0;

                        return ret;
                } else {
                        DRM_DEBUG_KMS("failed to get ESI - device may have failed\n");
                        intel_dp->is_mst = false;
                        drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
                                                        intel_dp->is_mst);
                }
        }
        return -EINVAL;
}

static bool
intel_dp_needs_link_retrain(struct intel_dp *intel_dp)
{
        u8 link_status[DP_LINK_STATUS_SIZE];

        if (!intel_dp->link_trained)
                return false;

        /*
         * While PSR source HW is enabled, it will control main-link sending
         * frames, enabling and disabling it so trying to do a retrain will fail
         * as the link would or not be on or it could mix training patterns
         * and frame data at the same time causing retrain to fail.
         * Also when exiting PSR, HW will retrain the link anyways fixing
         * any link status error.
         */
        if (intel_psr_enabled(intel_dp))
                return false;

        if (!intel_dp_get_link_status(intel_dp, link_status))
                return false;

        /*
         * Validate the cached values of intel_dp->link_rate and
         * intel_dp->lane_count before attempting to retrain.
         */
        if (!intel_dp_link_params_valid(intel_dp, intel_dp->link_rate,
                                        intel_dp->lane_count))
                return false;

        /* Retrain if Channel EQ or CR not ok */
        return !drm_dp_channel_eq_ok(link_status, intel_dp->lane_count);
}

int intel_dp_retrain_link(struct intel_encoder *encoder,
                          struct drm_modeset_acquire_ctx *ctx)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct intel_connector *connector = intel_dp->attached_connector;
        struct drm_connector_state *conn_state;
        struct intel_crtc_state *crtc_state;
        struct intel_crtc *crtc;
        int ret;

        /* FIXME handle the MST connectors as well */

        if (!connector || connector->base.status != connector_status_connected)
                return 0;

        ret = drm_modeset_lock(&dev_priv->drm.mode_config.connection_mutex,
                               ctx);
        if (ret)
                return ret;

        conn_state = connector->base.state;

        crtc = to_intel_crtc(conn_state->crtc);
        if (!crtc)
                return 0;

        ret = drm_modeset_lock(&crtc->base.mutex, ctx);
        if (ret)
                return ret;

        crtc_state = to_intel_crtc_state(crtc->base.state);

        WARN_ON(!intel_crtc_has_dp_encoder(crtc_state));

        if (!crtc_state->base.active)
                return 0;

        if (conn_state->commit &&
            !try_wait_for_completion(&conn_state->commit->hw_done))
                return 0;

        if (!intel_dp_needs_link_retrain(intel_dp))
                return 0;

        /* Suppress underruns caused by re-training */
        intel_set_cpu_fifo_underrun_reporting(dev_priv, crtc->pipe, false);
        if (crtc_state->has_pch_encoder)
                intel_set_pch_fifo_underrun_reporting(dev_priv,
                                                      intel_crtc_pch_transcoder(crtc), false);

        intel_dp_start_link_train(intel_dp);
        intel_dp_stop_link_train(intel_dp);

        /* Keep underrun reporting disabled until things are stable */
        intel_wait_for_vblank(dev_priv, crtc->pipe);

        intel_set_cpu_fifo_underrun_reporting(dev_priv, crtc->pipe, true);
        if (crtc_state->has_pch_encoder)
                intel_set_pch_fifo_underrun_reporting(dev_priv,
                                                      intel_crtc_pch_transcoder(crtc), true);

        return 0;
}

/*
 * If display is now connected check links status,
 * there has been known issues of link loss triggering
 * long pulse.
 *
 * Some sinks (eg. ASUS PB287Q) seem to perform some
 * weird HPD ping pong during modesets. So we can apparently
 * end up with HPD going low during a modeset, and then
 * going back up soon after. And once that happens we must
 * retrain the link to get a picture. That's in case no
 * userspace component reacted to intermittent HPD dip.
 */
static enum intel_hotplug_state
intel_dp_hotplug(struct intel_encoder *encoder,
                 struct intel_connector *connector,
                 bool irq_received)
{
        struct drm_modeset_acquire_ctx ctx;
        enum intel_hotplug_state state;
        int ret;

        state = intel_encoder_hotplug(encoder, connector, irq_received);

        drm_modeset_acquire_init(&ctx, 0);

        for (;;) {
                ret = intel_dp_retrain_link(encoder, &ctx);

                if (ret == -EDEADLK) {
                        drm_modeset_backoff(&ctx);
                        continue;
                }

                break;
        }

        drm_modeset_drop_locks(&ctx);
        drm_modeset_acquire_fini(&ctx);
        WARN(ret, "Acquiring modeset locks failed with %i\n", ret);

        /*
         * Keeping it consistent with intel_ddi_hotplug() and
         * intel_hdmi_hotplug().
         */
        if (state == INTEL_HOTPLUG_UNCHANGED && irq_received)
                state = INTEL_HOTPLUG_RETRY;

        return state;
}

static void intel_dp_check_service_irq(struct intel_dp *intel_dp)
{
        u8 val;

        if (intel_dp->dpcd[DP_DPCD_REV] < 0x11)
                return;

        if (drm_dp_dpcd_readb(&intel_dp->aux,
                              DP_DEVICE_SERVICE_IRQ_VECTOR, &val) != 1 || !val)
                return;

        drm_dp_dpcd_writeb(&intel_dp->aux, DP_DEVICE_SERVICE_IRQ_VECTOR, val);

        if (val & DP_AUTOMATED_TEST_REQUEST)
                intel_dp_handle_test_request(intel_dp);

        if (val & DP_CP_IRQ)
                intel_hdcp_handle_cp_irq(intel_dp->attached_connector);

        if (val & DP_SINK_SPECIFIC_IRQ)
                DRM_DEBUG_DRIVER("Sink specific irq unhandled\n");
}

/*
 * According to DP spec
 * 5.1.2:
 *  1. Read DPCD
 *  2. Configure link according to Receiver Capabilities
 *  3. Use Link Training from 2.5.3.3 and 3.5.1.3
 *  4. Check link status on receipt of hot-plug interrupt
 *
 * intel_dp_short_pulse -  handles short pulse interrupts
 * when full detection is not required.
 * Returns %true if short pulse is handled and full detection
 * is NOT required and %false otherwise.
 */
static bool
intel_dp_short_pulse(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        u8 old_sink_count = intel_dp->sink_count;
        bool ret;

        /*
         * Clearing compliance test variables to allow capturing
         * of values for next automated test request.
         */
        memset(&intel_dp->compliance, 0, sizeof(intel_dp->compliance));

        /*
         * Now read the DPCD to see if it's actually running
         * If the current value of sink count doesn't match with
         * the value that was stored earlier or dpcd read failed
         * we need to do full detection
         */
        ret = intel_dp_get_dpcd(intel_dp);

        if ((old_sink_count != intel_dp->sink_count) || !ret) {
                /* No need to proceed if we are going to do full detect */
                return false;
        }

        intel_dp_check_service_irq(intel_dp);

        /* Handle CEC interrupts, if any */
        drm_dp_cec_irq(&intel_dp->aux);

        /* defer to the hotplug work for link retraining if needed */
        if (intel_dp_needs_link_retrain(intel_dp))
                return false;

        intel_psr_short_pulse(intel_dp);

        if (intel_dp->compliance.test_type == DP_TEST_LINK_TRAINING) {
                DRM_DEBUG_KMS("Link Training Compliance Test requested\n");
                /* Send a Hotplug Uevent to userspace to start modeset */
                drm_kms_helper_hotplug_event(&dev_priv->drm);
        }

        return true;
}

/* XXX this is probably wrong for multiple downstream ports */
static enum drm_connector_status
intel_dp_detect_dpcd(struct intel_dp *intel_dp)
{
        struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp);
        u8 *dpcd = intel_dp->dpcd;
        u8 type;

        if (WARN_ON(intel_dp_is_edp(intel_dp)))
                return connector_status_connected;

        if (lspcon->active)
                lspcon_resume(lspcon);

        if (!intel_dp_get_dpcd(intel_dp))
                return connector_status_disconnected;

        /* if there's no downstream port, we're done */
        if (!drm_dp_is_branch(dpcd))
                return connector_status_connected;

        /* If we're HPD-aware, SINK_COUNT changes dynamically */
        if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
            intel_dp->downstream_ports[0] & DP_DS_PORT_HPD) {

                return intel_dp->sink_count ?
                connector_status_connected : connector_status_disconnected;
        }

        if (intel_dp_can_mst(intel_dp))
                return connector_status_connected;

        /* If no HPD, poke DDC gently */
        if (drm_probe_ddc(&intel_dp->aux.ddc))
                return connector_status_connected;

        /* Well we tried, say unknown for unreliable port types */
        if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11) {
                type = intel_dp->downstream_ports[0] & DP_DS_PORT_TYPE_MASK;
                if (type == DP_DS_PORT_TYPE_VGA ||
                    type == DP_DS_PORT_TYPE_NON_EDID)
                        return connector_status_unknown;
        } else {
                type = intel_dp->dpcd[DP_DOWNSTREAMPORT_PRESENT] &
                        DP_DWN_STRM_PORT_TYPE_MASK;
                if (type == DP_DWN_STRM_PORT_TYPE_ANALOG ||
                    type == DP_DWN_STRM_PORT_TYPE_OTHER)
                        return connector_status_unknown;
        }

        /* Anything else is out of spec, warn and ignore */
        DRM_DEBUG_KMS("Broken DP branch device, ignoring\n");
        return connector_status_disconnected;
}

static enum drm_connector_status
edp_detect(struct intel_dp *intel_dp)
{
        return connector_status_connected;
}

static bool ibx_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 bit;

        switch (encoder->hpd_pin) {
        case HPD_PORT_B:
                bit = SDE_PORTB_HOTPLUG;
                break;
        case HPD_PORT_C:
                bit = SDE_PORTC_HOTPLUG;
                break;
        case HPD_PORT_D:
                bit = SDE_PORTD_HOTPLUG;
                break;
        default:
                MISSING_CASE(encoder->hpd_pin);
                return false;
        }

        return I915_READ(SDEISR) & bit;
}

static bool cpt_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 bit;

        switch (encoder->hpd_pin) {
        case HPD_PORT_B:
                bit = SDE_PORTB_HOTPLUG_CPT;
                break;
        case HPD_PORT_C:
                bit = SDE_PORTC_HOTPLUG_CPT;
                break;
        case HPD_PORT_D:
                bit = SDE_PORTD_HOTPLUG_CPT;
                break;
        default:
                MISSING_CASE(encoder->hpd_pin);
                return false;
        }

        return I915_READ(SDEISR) & bit;
}

static bool spt_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 bit;

        switch (encoder->hpd_pin) {
        case HPD_PORT_A:
                bit = SDE_PORTA_HOTPLUG_SPT;
                break;
        case HPD_PORT_E:
                bit = SDE_PORTE_HOTPLUG_SPT;
                break;
        default:
                return cpt_digital_port_connected(encoder);
        }

        return I915_READ(SDEISR) & bit;
}

static bool g4x_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 bit;

        switch (encoder->hpd_pin) {
        case HPD_PORT_B:
                bit = PORTB_HOTPLUG_LIVE_STATUS_G4X;
                break;
        case HPD_PORT_C:
                bit = PORTC_HOTPLUG_LIVE_STATUS_G4X;
                break;
        case HPD_PORT_D:
                bit = PORTD_HOTPLUG_LIVE_STATUS_G4X;
                break;
        default:
                MISSING_CASE(encoder->hpd_pin);
                return false;
        }

        return I915_READ(PORT_HOTPLUG_STAT) & bit;
}

static bool gm45_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 bit;

        switch (encoder->hpd_pin) {
        case HPD_PORT_B:
                bit = PORTB_HOTPLUG_LIVE_STATUS_GM45;
                break;
        case HPD_PORT_C:
                bit = PORTC_HOTPLUG_LIVE_STATUS_GM45;
                break;
        case HPD_PORT_D:
                bit = PORTD_HOTPLUG_LIVE_STATUS_GM45;
                break;
        default:
                MISSING_CASE(encoder->hpd_pin);
                return false;
        }

        return I915_READ(PORT_HOTPLUG_STAT) & bit;
}

static bool ilk_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (encoder->hpd_pin == HPD_PORT_A)
                return I915_READ(DEISR) & DE_DP_A_HOTPLUG;
        else
                return ibx_digital_port_connected(encoder);
}

static bool snb_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (encoder->hpd_pin == HPD_PORT_A)
                return I915_READ(DEISR) & DE_DP_A_HOTPLUG;
        else
                return cpt_digital_port_connected(encoder);
}

static bool ivb_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (encoder->hpd_pin == HPD_PORT_A)
                return I915_READ(DEISR) & DE_DP_A_HOTPLUG_IVB;
        else
                return cpt_digital_port_connected(encoder);
}

static bool bdw_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (encoder->hpd_pin == HPD_PORT_A)
                return I915_READ(GEN8_DE_PORT_ISR) & GEN8_PORT_DP_A_HOTPLUG;
        else
                return cpt_digital_port_connected(encoder);
}

static bool bxt_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        u32 bit;

        switch (encoder->hpd_pin) {
        case HPD_PORT_A:
                bit = BXT_DE_PORT_HP_DDIA;
                break;
        case HPD_PORT_B:
                bit = BXT_DE_PORT_HP_DDIB;
                break;
        case HPD_PORT_C:
                bit = BXT_DE_PORT_HP_DDIC;
                break;
        default:
                MISSING_CASE(encoder->hpd_pin);
                return false;
        }

        return I915_READ(GEN8_DE_PORT_ISR) & bit;
}

static bool intel_combo_phy_connected(struct drm_i915_private *dev_priv,
                                      enum phy phy)
{
        if (HAS_PCH_MCC(dev_priv) && phy == PHY_C)
                return I915_READ(SDEISR) & SDE_TC_HOTPLUG_ICP(PORT_TC1);

        return I915_READ(SDEISR) & SDE_DDI_HOTPLUG_ICP(phy);
}

static bool icl_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        struct intel_digital_port *dig_port = enc_to_dig_port(&encoder->base);
        enum phy phy = intel_port_to_phy(dev_priv, encoder->port);

        if (intel_phy_is_combo(dev_priv, phy))
                return intel_combo_phy_connected(dev_priv, phy);
        else if (intel_phy_is_tc(dev_priv, phy))
                return intel_tc_port_connected(dig_port);
        else
                MISSING_CASE(encoder->hpd_pin);

        return false;
}

/*
 * intel_digital_port_connected - is the specified port connected?
 * @encoder: intel_encoder
 *
 * In cases where there's a connector physically connected but it can't be used
 * by our hardware we also return false, since the rest of the driver should
 * pretty much treat the port as disconnected. This is relevant for type-C
 * (starting on ICL) where there's ownership involved.
 *
 * Return %true if port is connected, %false otherwise.
 */
static bool __intel_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

        if (HAS_GMCH(dev_priv)) {
                if (IS_GM45(dev_priv))
                        return gm45_digital_port_connected(encoder);
                else
                        return g4x_digital_port_connected(encoder);
        }

        if (INTEL_GEN(dev_priv) >= 11)
                return icl_digital_port_connected(encoder);
        else if (IS_GEN(dev_priv, 10) || IS_GEN9_BC(dev_priv))
                return spt_digital_port_connected(encoder);
        else if (IS_GEN9_LP(dev_priv))
                return bxt_digital_port_connected(encoder);
        else if (IS_GEN(dev_priv, 8))
                return bdw_digital_port_connected(encoder);
        else if (IS_GEN(dev_priv, 7))
                return ivb_digital_port_connected(encoder);
        else if (IS_GEN(dev_priv, 6))
                return snb_digital_port_connected(encoder);
        else if (IS_GEN(dev_priv, 5))
                return ilk_digital_port_connected(encoder);

        MISSING_CASE(INTEL_GEN(dev_priv));
        return false;
}

bool intel_digital_port_connected(struct intel_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
        bool is_connected = false;
        intel_wakeref_t wakeref;

        with_intel_display_power(dev_priv, POWER_DOMAIN_DISPLAY_CORE, wakeref)
                is_connected = __intel_digital_port_connected(encoder);

        return is_connected;
}

static struct edid *
intel_dp_get_edid(struct intel_dp *intel_dp)
{
        struct intel_connector *intel_connector = intel_dp->attached_connector;

        /* use cached edid if we have one */
        if (intel_connector->edid) {
                /* invalid edid */
                if (IS_ERR(intel_connector->edid))
                        return NULL;

                return drm_edid_duplicate(intel_connector->edid);
        } else
                return drm_get_edid(&intel_connector->base,
                                    &intel_dp->aux.ddc);
}

static void
intel_dp_set_edid(struct intel_dp *intel_dp)
{
        struct intel_connector *intel_connector = intel_dp->attached_connector;
        struct edid *edid;

        intel_dp_unset_edid(intel_dp);
        edid = intel_dp_get_edid(intel_dp);
        intel_connector->detect_edid = edid;

        intel_dp->has_audio = drm_detect_monitor_audio(edid);
        drm_dp_cec_set_edid(&intel_dp->aux, edid);
}

static void
intel_dp_unset_edid(struct intel_dp *intel_dp)
{
        struct intel_connector *intel_connector = intel_dp->attached_connector;

        drm_dp_cec_unset_edid(&intel_dp->aux);
        kfree(intel_connector->detect_edid);
        intel_connector->detect_edid = NULL;

        intel_dp->has_audio = false;
}

static int
intel_dp_detect(struct drm_connector *connector,
                struct drm_modeset_acquire_ctx *ctx,
                bool force)
{
        struct drm_i915_private *dev_priv = to_i915(connector->dev);
        struct intel_dp *intel_dp = intel_attached_dp(connector);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct intel_encoder *encoder = &dig_port->base;
        enum drm_connector_status status;

        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
                      connector->base.id, connector->name);
        WARN_ON(!drm_modeset_is_locked(&dev_priv->drm.mode_config.connection_mutex));

        /* Can't disconnect eDP */
        if (intel_dp_is_edp(intel_dp))
                status = edp_detect(intel_dp);
        else if (intel_digital_port_connected(encoder))
                status = intel_dp_detect_dpcd(intel_dp);
        else
                status = connector_status_disconnected;

        if (status == connector_status_disconnected) {
                memset(&intel_dp->compliance, 0, sizeof(intel_dp->compliance));
                memset(intel_dp->dsc_dpcd, 0, sizeof(intel_dp->dsc_dpcd));

                if (intel_dp->is_mst) {
                        DRM_DEBUG_KMS("MST device may have disappeared %d vs %d\n",
                                      intel_dp->is_mst,
                                      intel_dp->mst_mgr.mst_state);
                        intel_dp->is_mst = false;
                        drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
                                                        intel_dp->is_mst);
                }

                goto out;
        }

        if (intel_dp->reset_link_params) {
                /* Initial max link lane count */
                intel_dp->max_link_lane_count = intel_dp_max_common_lane_count(intel_dp);

                /* Initial max link rate */
                intel_dp->max_link_rate = intel_dp_max_common_rate(intel_dp);

                intel_dp->reset_link_params = false;
        }

        intel_dp_print_rates(intel_dp);

        /* Read DP Sink DSC Cap DPCD regs for DP v1.4 */
        if (INTEL_GEN(dev_priv) >= 11)
                intel_dp_get_dsc_sink_cap(intel_dp);

        intel_dp_configure_mst(intel_dp);

        if (intel_dp->is_mst) {
                /*
                 * If we are in MST mode then this connector
                 * won't appear connected or have anything
                 * with EDID on it
                 */
                status = connector_status_disconnected;
                goto out;
        }

        /*
         * Some external monitors do not signal loss of link synchronization
         * with an IRQ_HPD, so force a link status check.
         */
        if (!intel_dp_is_edp(intel_dp)) {
                int ret;

                ret = intel_dp_retrain_link(encoder, ctx);
                if (ret)
                        return ret;
        }

        /*
         * Clearing NACK and defer counts to get their exact values
         * while reading EDID which are required by Compliance tests
         * 4.2.2.4 and 4.2.2.5
         */
        intel_dp->aux.i2c_nack_count = 0;
        intel_dp->aux.i2c_defer_count = 0;

        intel_dp_set_edid(intel_dp);
        if (intel_dp_is_edp(intel_dp) ||
            to_intel_connector(connector)->detect_edid)
                status = connector_status_connected;

        intel_dp_check_service_irq(intel_dp);

out:
        if (status != connector_status_connected && !intel_dp->is_mst)
                intel_dp_unset_edid(intel_dp);

        /*
         * Make sure the refs for power wells enabled during detect are
         * dropped to avoid a new detect cycle triggered by HPD polling.
         */
        intel_display_power_flush_work(dev_priv);

        return status;
}

static void
intel_dp_force(struct drm_connector *connector)
{
        struct intel_dp *intel_dp = intel_attached_dp(connector);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        struct intel_encoder *intel_encoder = &dig_port->base;
        struct drm_i915_private *dev_priv = to_i915(intel_encoder->base.dev);
        enum intel_display_power_domain aux_domain =
                intel_aux_power_domain(dig_port);
        intel_wakeref_t wakeref;

        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
                      connector->base.id, connector->name);
        intel_dp_unset_edid(intel_dp);

        if (connector->status != connector_status_connected)
                return;

        wakeref = intel_display_power_get(dev_priv, aux_domain);

        intel_dp_set_edid(intel_dp);

        intel_display_power_put(dev_priv, aux_domain, wakeref);
}

static int intel_dp_get_modes(struct drm_connector *connector)
{
        struct intel_connector *intel_connector = to_intel_connector(connector);
        struct edid *edid;

        edid = intel_connector->detect_edid;
        if (edid) {
                int ret = intel_connector_update_modes(connector, edid);
                if (ret)
                        return ret;
        }

        /* if eDP has no EDID, fall back to fixed mode */
        if (intel_dp_is_edp(intel_attached_dp(connector)) &&
            intel_connector->panel.fixed_mode) {
                struct drm_display_mode *mode;

                mode = drm_mode_duplicate(connector->dev,
                                          intel_connector->panel.fixed_mode);
                if (mode) {
                        drm_mode_probed_add(connector, mode);
                        return 1;
                }
        }

        return 0;
}

static int
intel_dp_connector_register(struct drm_connector *connector)
{
        struct intel_dp *intel_dp = intel_attached_dp(connector);
        int ret;

        ret = intel_connector_register(connector);
        if (ret)
                return ret;

        i915_debugfs_connector_add(connector);

        DRM_DEBUG_KMS("registering %s bus for %s\n",
                      intel_dp->aux.name, connector->kdev->kobj.name);

        intel_dp->aux.dev = connector->kdev;
        ret = drm_dp_aux_register(&intel_dp->aux);
        if (!ret)
                drm_dp_cec_register_connector(&intel_dp->aux, connector);
        return ret;
}

static void
intel_dp_connector_unregister(struct drm_connector *connector)
{
        struct intel_dp *intel_dp = intel_attached_dp(connector);

        drm_dp_cec_unregister_connector(&intel_dp->aux);
        drm_dp_aux_unregister(&intel_dp->aux);
        intel_connector_unregister(connector);
}

void intel_dp_encoder_flush_work(struct drm_encoder *encoder)
{
        struct intel_digital_port *intel_dig_port = enc_to_dig_port(encoder);
        struct intel_dp *intel_dp = &intel_dig_port->dp;

        intel_dp_mst_encoder_cleanup(intel_dig_port);
        if (intel_dp_is_edp(intel_dp)) {
                intel_wakeref_t wakeref;

                cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
                /*
                 * vdd might still be enabled do to the delayed vdd off.
                 * Make sure vdd is actually turned off here.
                 */
                with_pps_lock(intel_dp, wakeref)
                        edp_panel_vdd_off_sync(intel_dp);

                if (intel_dp->edp_notifier.notifier_call) {
                        unregister_reboot_notifier(&intel_dp->edp_notifier);
                        intel_dp->edp_notifier.notifier_call = NULL;
                }
        }

        intel_dp_aux_fini(intel_dp);
}

static void intel_dp_encoder_destroy(struct drm_encoder *encoder)
{
        intel_dp_encoder_flush_work(encoder);

        drm_encoder_cleanup(encoder);
        kfree(enc_to_dig_port(encoder));
}

void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(&intel_encoder->base);
        intel_wakeref_t wakeref;

        if (!intel_dp_is_edp(intel_dp))
                return;

        /*
         * vdd might still be enabled do to the delayed vdd off.
         * Make sure vdd is actually turned off here.
         */
        cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
        with_pps_lock(intel_dp, wakeref)
                edp_panel_vdd_off_sync(intel_dp);
}

static void intel_dp_hdcp_wait_for_cp_irq(struct intel_hdcp *hdcp, int timeout)
{
        long ret;

#define C (hdcp->cp_irq_count_cached != atomic_read(&hdcp->cp_irq_count))
        ret = wait_event_interruptible_timeout(hdcp->cp_irq_queue, C,
                                               msecs_to_jiffies(timeout));

        if (!ret)
                DRM_DEBUG_KMS("Timedout at waiting for CP_IRQ\n");
}

static
int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *intel_dig_port,
                                u8 *an)
{
        struct intel_dp *intel_dp = enc_to_intel_dp(&intel_dig_port->base.base);
        static const struct drm_dp_aux_msg msg = {
                .request = DP_AUX_NATIVE_WRITE,
                .address = DP_AUX_HDCP_AKSV,
                .size = DRM_HDCP_KSV_LEN,
        };
        u8 txbuf[HEADER_SIZE + DRM_HDCP_KSV_LEN] = {}, rxbuf[2], reply = 0;
        ssize_t dpcd_ret;
        int ret;

        /* Output An first, that's easy */
        dpcd_ret = drm_dp_dpcd_write(&intel_dig_port->dp.aux, DP_AUX_HDCP_AN,
                                     an, DRM_HDCP_AN_LEN);
        if (dpcd_ret != DRM_HDCP_AN_LEN) {
                DRM_DEBUG_KMS("Failed to write An over DP/AUX (%zd)\n",
                              dpcd_ret);
                return dpcd_ret >= 0 ? -EIO : dpcd_ret;
        }

        /*
         * Since Aksv is Oh-So-Secret, we can't access it in software. So in
         * order to get it on the wire, we need to create the AUX header as if
         * we were writing the data, and then tickle the hardware to output the
         * data once the header is sent out.
         */
        intel_dp_aux_header(txbuf, &msg);

        ret = intel_dp_aux_xfer(intel_dp, txbuf, HEADER_SIZE + msg.size,
                                rxbuf, sizeof(rxbuf),
                                DP_AUX_CH_CTL_AUX_AKSV_SELECT);
        if (ret < 0) {
                DRM_DEBUG_KMS("Write Aksv over DP/AUX failed (%d)\n", ret);
                return ret;
        } else if (ret == 0) {
                DRM_DEBUG_KMS("Aksv write over DP/AUX was empty\n");
                return -EIO;
        }

        reply = (rxbuf[0] >> 4) & DP_AUX_NATIVE_REPLY_MASK;
        if (reply != DP_AUX_NATIVE_REPLY_ACK) {
                DRM_DEBUG_KMS("Aksv write: no DP_AUX_NATIVE_REPLY_ACK %x\n",
                              reply);
                return -EIO;
        }
        return 0;
}

static int intel_dp_hdcp_read_bksv(struct intel_digital_port *intel_dig_port,
                                   u8 *bksv)
{
        ssize_t ret;
        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BKSV, bksv,
                               DRM_HDCP_KSV_LEN);
        if (ret != DRM_HDCP_KSV_LEN) {
                DRM_DEBUG_KMS("Read Bksv from DP/AUX failed (%zd)\n", ret);
                return ret >= 0 ? -EIO : ret;
        }
        return 0;
}

static int intel_dp_hdcp_read_bstatus(struct intel_digital_port *intel_dig_port,
                                      u8 *bstatus)
{
        ssize_t ret;
        /*
         * For some reason the HDMI and DP HDCP specs call this register
         * definition by different names. In the HDMI spec, it's called BSTATUS,
         * but in DP it's called BINFO.
         */
        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BINFO,
                               bstatus, DRM_HDCP_BSTATUS_LEN);
        if (ret != DRM_HDCP_BSTATUS_LEN) {
                DRM_DEBUG_KMS("Read bstatus from DP/AUX failed (%zd)\n", ret);
                return ret >= 0 ? -EIO : ret;
        }
        return 0;
}

static
int intel_dp_hdcp_read_bcaps(struct intel_digital_port *intel_dig_port,
                             u8 *bcaps)
{
        ssize_t ret;

        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BCAPS,
                               bcaps, 1);
        if (ret != 1) {
                DRM_DEBUG_KMS("Read bcaps from DP/AUX failed (%zd)\n", ret);
                return ret >= 0 ? -EIO : ret;
        }

        return 0;
}

static
int intel_dp_hdcp_repeater_present(struct intel_digital_port *intel_dig_port,
                                   bool *repeater_present)
{
        ssize_t ret;
        u8 bcaps;

        ret = intel_dp_hdcp_read_bcaps(intel_dig_port, &bcaps);
        if (ret)
                return ret;

        *repeater_present = bcaps & DP_BCAPS_REPEATER_PRESENT;
        return 0;
}

static
int intel_dp_hdcp_read_ri_prime(struct intel_digital_port *intel_dig_port,
                                u8 *ri_prime)
{
        ssize_t ret;
        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_RI_PRIME,
                               ri_prime, DRM_HDCP_RI_LEN);
        if (ret != DRM_HDCP_RI_LEN) {
                DRM_DEBUG_KMS("Read Ri' from DP/AUX failed (%zd)\n", ret);
                return ret >= 0 ? -EIO : ret;
        }
        return 0;
}

static
int intel_dp_hdcp_read_ksv_ready(struct intel_digital_port *intel_dig_port,
                                 bool *ksv_ready)
{
        ssize_t ret;
        u8 bstatus;
        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BSTATUS,
                               &bstatus, 1);
        if (ret != 1) {
                DRM_DEBUG_KMS("Read bstatus from DP/AUX failed (%zd)\n", ret);
                return ret >= 0 ? -EIO : ret;
        }
        *ksv_ready = bstatus & DP_BSTATUS_READY;
        return 0;
}

static
int intel_dp_hdcp_read_ksv_fifo(struct intel_digital_port *intel_dig_port,
                                int num_downstream, u8 *ksv_fifo)
{
        ssize_t ret;
        int i;

        /* KSV list is read via 15 byte window (3 entries @ 5 bytes each) */
        for (i = 0; i < num_downstream; i += 3) {
                size_t len = min(num_downstream - i, 3) * DRM_HDCP_KSV_LEN;
                ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux,
                                       DP_AUX_HDCP_KSV_FIFO,
                                       ksv_fifo + i * DRM_HDCP_KSV_LEN,
                                       len);
                if (ret != len) {
                        DRM_DEBUG_KMS("Read ksv[%d] from DP/AUX failed (%zd)\n",
                                      i, ret);
                        return ret >= 0 ? -EIO : ret;
                }
        }
        return 0;
}

static
int intel_dp_hdcp_read_v_prime_part(struct intel_digital_port *intel_dig_port,
                                    int i, u32 *part)
{
        ssize_t ret;

        if (i >= DRM_HDCP_V_PRIME_NUM_PARTS)
                return -EINVAL;

        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux,
                               DP_AUX_HDCP_V_PRIME(i), part,
                               DRM_HDCP_V_PRIME_PART_LEN);
        if (ret != DRM_HDCP_V_PRIME_PART_LEN) {
                DRM_DEBUG_KMS("Read v'[%d] from DP/AUX failed (%zd)\n", i, ret);
                return ret >= 0 ? -EIO : ret;
        }
        return 0;
}

static
int intel_dp_hdcp_toggle_signalling(struct intel_digital_port *intel_dig_port,
                                    bool enable)
{
        /* Not used for single stream DisplayPort setups */
        return 0;
}

static
bool intel_dp_hdcp_check_link(struct intel_digital_port *intel_dig_port)
{
        ssize_t ret;
        u8 bstatus;

        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, DP_AUX_HDCP_BSTATUS,
                               &bstatus, 1);
        if (ret != 1) {
                DRM_DEBUG_KMS("Read bstatus from DP/AUX failed (%zd)\n", ret);
                return false;
        }

        return !(bstatus & (DP_BSTATUS_LINK_FAILURE | DP_BSTATUS_REAUTH_REQ));
}

static
int intel_dp_hdcp_capable(struct intel_digital_port *intel_dig_port,
                          bool *hdcp_capable)
{
        ssize_t ret;
        u8 bcaps;

        ret = intel_dp_hdcp_read_bcaps(intel_dig_port, &bcaps);
        if (ret)
                return ret;

        *hdcp_capable = bcaps & DP_BCAPS_HDCP_CAPABLE;
        return 0;
}

struct hdcp2_dp_errata_stream_type {
        u8      msg_id;
        u8      stream_type;
} __packed;

struct hdcp2_dp_msg_data {
        u8 msg_id;
        u32 offset;
        bool msg_detectable;
        u32 timeout;
        u32 timeout2; /* Added for non_paired situation */
};

static const struct hdcp2_dp_msg_data hdcp2_dp_msg_data[] = {
        { HDCP_2_2_AKE_INIT, DP_HDCP_2_2_AKE_INIT_OFFSET, false, 0, 0 },
        { HDCP_2_2_AKE_SEND_CERT, DP_HDCP_2_2_AKE_SEND_CERT_OFFSET,
          false, HDCP_2_2_CERT_TIMEOUT_MS, 0 },
        { HDCP_2_2_AKE_NO_STORED_KM, DP_HDCP_2_2_AKE_NO_STORED_KM_OFFSET,
          false, 0, 0 },
        { HDCP_2_2_AKE_STORED_KM, DP_HDCP_2_2_AKE_STORED_KM_OFFSET,
          false, 0, 0 },
        { HDCP_2_2_AKE_SEND_HPRIME, DP_HDCP_2_2_AKE_SEND_HPRIME_OFFSET,
          true, HDCP_2_2_HPRIME_PAIRED_TIMEOUT_MS,
          HDCP_2_2_HPRIME_NO_PAIRED_TIMEOUT_MS },
        { HDCP_2_2_AKE_SEND_PAIRING_INFO,
          DP_HDCP_2_2_AKE_SEND_PAIRING_INFO_OFFSET, true,
          HDCP_2_2_PAIRING_TIMEOUT_MS, 0 },
        { HDCP_2_2_LC_INIT, DP_HDCP_2_2_LC_INIT_OFFSET, false, 0, 0 },
        { HDCP_2_2_LC_SEND_LPRIME, DP_HDCP_2_2_LC_SEND_LPRIME_OFFSET,
          false, HDCP_2_2_DP_LPRIME_TIMEOUT_MS, 0 },
        { HDCP_2_2_SKE_SEND_EKS, DP_HDCP_2_2_SKE_SEND_EKS_OFFSET, false,
          0, 0 },
        { HDCP_2_2_REP_SEND_RECVID_LIST,
          DP_HDCP_2_2_REP_SEND_RECVID_LIST_OFFSET, true,
          HDCP_2_2_RECVID_LIST_TIMEOUT_MS, 0 },
        { HDCP_2_2_REP_SEND_ACK, DP_HDCP_2_2_REP_SEND_ACK_OFFSET, false,
          0, 0 },
        { HDCP_2_2_REP_STREAM_MANAGE,
          DP_HDCP_2_2_REP_STREAM_MANAGE_OFFSET, false,
          0, 0 },
        { HDCP_2_2_REP_STREAM_READY, DP_HDCP_2_2_REP_STREAM_READY_OFFSET,
          false, HDCP_2_2_STREAM_READY_TIMEOUT_MS, 0 },
/* local define to shovel this through the write_2_2 interface */
#define HDCP_2_2_ERRATA_DP_STREAM_TYPE  50
        { HDCP_2_2_ERRATA_DP_STREAM_TYPE,
          DP_HDCP_2_2_REG_STREAM_TYPE_OFFSET, false,
          0, 0 },
};

static inline
int intel_dp_hdcp2_read_rx_status(struct intel_digital_port *intel_dig_port,
                                  u8 *rx_status)
{
        ssize_t ret;

        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux,
                               DP_HDCP_2_2_REG_RXSTATUS_OFFSET, rx_status,
                               HDCP_2_2_DP_RXSTATUS_LEN);
        if (ret != HDCP_2_2_DP_RXSTATUS_LEN) {
                DRM_DEBUG_KMS("Read bstatus from DP/AUX failed (%zd)\n", ret);
                return ret >= 0 ? -EIO : ret;
        }

        return 0;
}

static
int hdcp2_detect_msg_availability(struct intel_digital_port *intel_dig_port,
                                  u8 msg_id, bool *msg_ready)
{
        u8 rx_status;
        int ret;

        *msg_ready = false;
        ret = intel_dp_hdcp2_read_rx_status(intel_dig_port, &rx_status);
        if (ret < 0)
                return ret;

        switch (msg_id) {
        case HDCP_2_2_AKE_SEND_HPRIME:
                if (HDCP_2_2_DP_RXSTATUS_H_PRIME(rx_status))
                        *msg_ready = true;
                break;
        case HDCP_2_2_AKE_SEND_PAIRING_INFO:
                if (HDCP_2_2_DP_RXSTATUS_PAIRING(rx_status))
                        *msg_ready = true;
                break;
        case HDCP_2_2_REP_SEND_RECVID_LIST:
                if (HDCP_2_2_DP_RXSTATUS_READY(rx_status))
                        *msg_ready = true;
                break;
        default:
                DRM_ERROR("Unidentified msg_id: %d\n", msg_id);
                return -EINVAL;
        }

        return 0;
}

static ssize_t
intel_dp_hdcp2_wait_for_msg(struct intel_digital_port *intel_dig_port,
                            const struct hdcp2_dp_msg_data *hdcp2_msg_data)
{
        struct intel_dp *dp = &intel_dig_port->dp;
        struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
        u8 msg_id = hdcp2_msg_data->msg_id;
        int ret, timeout;
        bool msg_ready = false;

        if (msg_id == HDCP_2_2_AKE_SEND_HPRIME && !hdcp->is_paired)
                timeout = hdcp2_msg_data->timeout2;
        else
                timeout = hdcp2_msg_data->timeout;

        /*
         * There is no way to detect the CERT, LPRIME and STREAM_READY
         * availability. So Wait for timeout and read the msg.
         */
        if (!hdcp2_msg_data->msg_detectable) {
                mdelay(timeout);
                ret = 0;
        } else {
                /*
                 * As we want to check the msg availability at timeout, Ignoring
                 * the timeout at wait for CP_IRQ.
                 */
                intel_dp_hdcp_wait_for_cp_irq(hdcp, timeout);
                ret = hdcp2_detect_msg_availability(intel_dig_port,
                                                    msg_id, &msg_ready);
                if (!msg_ready)
                        ret = -ETIMEDOUT;
        }

        if (ret)
                DRM_DEBUG_KMS("msg_id %d, ret %d, timeout(mSec): %d\n",
                              hdcp2_msg_data->msg_id, ret, timeout);

        return ret;
}

static const struct hdcp2_dp_msg_data *get_hdcp2_dp_msg_data(u8 msg_id)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(hdcp2_dp_msg_data); i++)
                if (hdcp2_dp_msg_data[i].msg_id == msg_id)
                        return &hdcp2_dp_msg_data[i];

        return NULL;
}

static
int intel_dp_hdcp2_write_msg(struct intel_digital_port *intel_dig_port,
                             void *buf, size_t size)
{
        struct intel_dp *dp = &intel_dig_port->dp;
        struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
        unsigned int offset;
        u8 *byte = buf;
        ssize_t ret, bytes_to_write, len;
        const struct hdcp2_dp_msg_data *hdcp2_msg_data;

        hdcp2_msg_data = get_hdcp2_dp_msg_data(*byte);
        if (!hdcp2_msg_data)
                return -EINVAL;

        offset = hdcp2_msg_data->offset;

        /* No msg_id in DP HDCP2.2 msgs */
        bytes_to_write = size - 1;
        byte++;

        hdcp->cp_irq_count_cached = atomic_read(&hdcp->cp_irq_count);

        while (bytes_to_write) {
                len = bytes_to_write > DP_AUX_MAX_PAYLOAD_BYTES ?
                                DP_AUX_MAX_PAYLOAD_BYTES : bytes_to_write;

                ret = drm_dp_dpcd_write(&intel_dig_port->dp.aux,
                                        offset, (void *)byte, len);
                if (ret < 0)
                        return ret;

                bytes_to_write -= ret;
                byte += ret;
                offset += ret;
        }

        return size;
}

static
ssize_t get_receiver_id_list_size(struct intel_digital_port *intel_dig_port)
{
        u8 rx_info[HDCP_2_2_RXINFO_LEN];
        u32 dev_cnt;
        ssize_t ret;

        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux,
                               DP_HDCP_2_2_REG_RXINFO_OFFSET,
                               (void *)rx_info, HDCP_2_2_RXINFO_LEN);
        if (ret != HDCP_2_2_RXINFO_LEN)
                return ret >= 0 ? -EIO : ret;

        dev_cnt = (HDCP_2_2_DEV_COUNT_HI(rx_info[0]) << 4 |
                   HDCP_2_2_DEV_COUNT_LO(rx_info[1]));

        if (dev_cnt > HDCP_2_2_MAX_DEVICE_COUNT)
                dev_cnt = HDCP_2_2_MAX_DEVICE_COUNT;

        ret = sizeof(struct hdcp2_rep_send_receiverid_list) -
                HDCP_2_2_RECEIVER_IDS_MAX_LEN +
                (dev_cnt * HDCP_2_2_RECEIVER_ID_LEN);

        return ret;
}

static
int intel_dp_hdcp2_read_msg(struct intel_digital_port *intel_dig_port,
                            u8 msg_id, void *buf, size_t size)
{
        unsigned int offset;
        u8 *byte = buf;
        ssize_t ret, bytes_to_recv, len;
        const struct hdcp2_dp_msg_data *hdcp2_msg_data;

        hdcp2_msg_data = get_hdcp2_dp_msg_data(msg_id);
        if (!hdcp2_msg_data)
                return -EINVAL;
        offset = hdcp2_msg_data->offset;

        ret = intel_dp_hdcp2_wait_for_msg(intel_dig_port, hdcp2_msg_data);
        if (ret < 0)
                return ret;

        if (msg_id == HDCP_2_2_REP_SEND_RECVID_LIST) {
                ret = get_receiver_id_list_size(intel_dig_port);
                if (ret < 0)
                        return ret;

                size = ret;
        }
        bytes_to_recv = size - 1;

        /* DP adaptation msgs has no msg_id */
        byte++;

        while (bytes_to_recv) {
                len = bytes_to_recv > DP_AUX_MAX_PAYLOAD_BYTES ?
                      DP_AUX_MAX_PAYLOAD_BYTES : bytes_to_recv;

                ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux, offset,
                                       (void *)byte, len);
                if (ret < 0) {
                        DRM_DEBUG_KMS("msg_id %d, ret %zd\n", msg_id, ret);
                        return ret;
                }

                bytes_to_recv -= ret;
                byte += ret;
                offset += ret;
        }
        byte = buf;
        *byte = msg_id;

        return size;
}

static
int intel_dp_hdcp2_config_stream_type(struct intel_digital_port *intel_dig_port,
                                      bool is_repeater, u8 content_type)
{
        struct hdcp2_dp_errata_stream_type stream_type_msg;

        if (is_repeater)
                return 0;

        /*
         * Errata for DP: As Stream type is used for encryption, Receiver
         * should be communicated with stream type for the decryption of the
         * content.
         * Repeater will be communicated with stream type as a part of it's
         * auth later in time.
         */
        stream_type_msg.msg_id = HDCP_2_2_ERRATA_DP_STREAM_TYPE;
        stream_type_msg.stream_type = content_type;

        return intel_dp_hdcp2_write_msg(intel_dig_port, &stream_type_msg,
                                        sizeof(stream_type_msg));
}

static
int intel_dp_hdcp2_check_link(struct intel_digital_port *intel_dig_port)
{
        u8 rx_status;
        int ret;

        ret = intel_dp_hdcp2_read_rx_status(intel_dig_port, &rx_status);
        if (ret)
                return ret;

        if (HDCP_2_2_DP_RXSTATUS_REAUTH_REQ(rx_status))
                ret = HDCP_REAUTH_REQUEST;
        else if (HDCP_2_2_DP_RXSTATUS_LINK_FAILED(rx_status))
                ret = HDCP_LINK_INTEGRITY_FAILURE;
        else if (HDCP_2_2_DP_RXSTATUS_READY(rx_status))
                ret = HDCP_TOPOLOGY_CHANGE;

        return ret;
}

static
int intel_dp_hdcp2_capable(struct intel_digital_port *intel_dig_port,
                           bool *capable)
{
        u8 rx_caps[3];
        int ret;

        *capable = false;
        ret = drm_dp_dpcd_read(&intel_dig_port->dp.aux,
                               DP_HDCP_2_2_REG_RX_CAPS_OFFSET,
                               rx_caps, HDCP_2_2_RXCAPS_LEN);
        if (ret != HDCP_2_2_RXCAPS_LEN)
                return ret >= 0 ? -EIO : ret;

        if (rx_caps[0] == HDCP_2_2_RX_CAPS_VERSION_VAL &&
            HDCP_2_2_DP_HDCP_CAPABLE(rx_caps[2]))
                *capable = true;

        return 0;
}

static const struct intel_hdcp_shim intel_dp_hdcp_shim = {
        .write_an_aksv = intel_dp_hdcp_write_an_aksv,
        .read_bksv = intel_dp_hdcp_read_bksv,
        .read_bstatus = intel_dp_hdcp_read_bstatus,
        .repeater_present = intel_dp_hdcp_repeater_present,
        .read_ri_prime = intel_dp_hdcp_read_ri_prime,
        .read_ksv_ready = intel_dp_hdcp_read_ksv_ready,
        .read_ksv_fifo = intel_dp_hdcp_read_ksv_fifo,
        .read_v_prime_part = intel_dp_hdcp_read_v_prime_part,
        .toggle_signalling = intel_dp_hdcp_toggle_signalling,
        .check_link = intel_dp_hdcp_check_link,
        .hdcp_capable = intel_dp_hdcp_capable,
        .write_2_2_msg = intel_dp_hdcp2_write_msg,
        .read_2_2_msg = intel_dp_hdcp2_read_msg,
        .config_stream_type = intel_dp_hdcp2_config_stream_type,
        .check_2_2_link = intel_dp_hdcp2_check_link,
        .hdcp_2_2_capable = intel_dp_hdcp2_capable,
        .protocol = HDCP_PROTOCOL_DP,
};

static void intel_edp_panel_vdd_sanitize(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);

        lockdep_assert_held(&dev_priv->pps_mutex);

        if (!edp_have_panel_vdd(intel_dp))
                return;

        /*
         * The VDD bit needs a power domain reference, so if the bit is
         * already enabled when we boot or resume, grab this reference and
         * schedule a vdd off, so we don't hold on to the reference
         * indefinitely.
         */
        DRM_DEBUG_KMS("VDD left on by BIOS, adjusting state tracking\n");
        intel_display_power_get(dev_priv, intel_aux_power_domain(dig_port));

        edp_panel_vdd_schedule_off(intel_dp);
}

static enum pipe vlv_active_pipe(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
        enum pipe pipe;

        if (intel_dp_port_enabled(dev_priv, intel_dp->output_reg,
                                  encoder->port, &pipe))
                return pipe;

        return INVALID_PIPE;
}

void intel_dp_encoder_reset(struct drm_encoder *encoder)
{
        struct drm_i915_private *dev_priv = to_i915(encoder->dev);
        struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
        struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp);
        intel_wakeref_t wakeref;

        if (!HAS_DDI(dev_priv))
                intel_dp->DP = I915_READ(intel_dp->output_reg);

        if (lspcon->active)
                lspcon_resume(lspcon);

        intel_dp->reset_link_params = true;

        if (!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv) &&
            !intel_dp_is_edp(intel_dp))
                return;

        with_pps_lock(intel_dp, wakeref) {
                if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                        intel_dp->active_pipe = vlv_active_pipe(intel_dp);

                if (intel_dp_is_edp(intel_dp)) {
                        /*
                         * Reinit the power sequencer, in case BIOS did
                         * something nasty with it.
                         */
                        intel_dp_pps_init(intel_dp);
                        intel_edp_panel_vdd_sanitize(intel_dp);
                }
        }
}

static const struct drm_connector_funcs intel_dp_connector_funcs = {
        .force = intel_dp_force,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .atomic_get_property = intel_digital_connector_atomic_get_property,
        .atomic_set_property = intel_digital_connector_atomic_set_property,
        .late_register = intel_dp_connector_register,
        .early_unregister = intel_dp_connector_unregister,
        .destroy = intel_connector_destroy,
        .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
        .atomic_duplicate_state = intel_digital_connector_duplicate_state,
};

static const struct drm_connector_helper_funcs intel_dp_connector_helper_funcs = {
        .detect_ctx = intel_dp_detect,
        .get_modes = intel_dp_get_modes,
        .mode_valid = intel_dp_mode_valid,
        .atomic_check = intel_digital_connector_atomic_check,
};

static const struct drm_encoder_funcs intel_dp_enc_funcs = {
        .reset = intel_dp_encoder_reset,
        .destroy = intel_dp_encoder_destroy,
};

enum irqreturn
intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd)
{
        struct intel_dp *intel_dp = &intel_dig_port->dp;

        if (long_hpd && intel_dig_port->base.type == INTEL_OUTPUT_EDP) {
                /*
                 * vdd off can generate a long pulse on eDP which
                 * would require vdd on to handle it, and thus we
                 * would end up in an endless cycle of
                 * "vdd off -> long hpd -> vdd on -> detect -> vdd off -> ..."
                 */
                DRM_DEBUG_KMS("ignoring long hpd on eDP [ENCODER:%d:%s]\n",
                              intel_dig_port->base.base.base.id,
                              intel_dig_port->base.base.name);
                return IRQ_HANDLED;
        }

        DRM_DEBUG_KMS("got hpd irq on [ENCODER:%d:%s] - %s\n",
                      intel_dig_port->base.base.base.id,
                      intel_dig_port->base.base.name,
                      long_hpd ? "long" : "short");

        if (long_hpd) {
                intel_dp->reset_link_params = true;
                return IRQ_NONE;
        }

        if (intel_dp->is_mst) {
                if (intel_dp_check_mst_status(intel_dp) == -EINVAL) {
                        /*
                         * If we were in MST mode, and device is not
                         * there, get out of MST mode
                         */
                        DRM_DEBUG_KMS("MST device may have disappeared %d vs %d\n",
                                      intel_dp->is_mst, intel_dp->mst_mgr.mst_state);
                        intel_dp->is_mst = false;
                        drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
                                                        intel_dp->is_mst);

                        return IRQ_NONE;
                }
        }

        if (!intel_dp->is_mst) {
                bool handled;

                handled = intel_dp_short_pulse(intel_dp);

                if (!handled)
                        return IRQ_NONE;
        }

        return IRQ_HANDLED;
}

/* check the VBT to see whether the eDP is on another port */
bool intel_dp_is_port_edp(struct drm_i915_private *dev_priv, enum port port)
{
        /*
         * eDP not supported on g4x. so bail out early just
         * for a bit extra safety in case the VBT is bonkers.
         */
        if (INTEL_GEN(dev_priv) < 5)
                return false;

        if (INTEL_GEN(dev_priv) < 9 && port == PORT_A)
                return true;

        return intel_bios_is_port_edp(dev_priv, port);
}

static void
intel_dp_add_properties(struct intel_dp *intel_dp, struct drm_connector *connector)
{
        struct drm_i915_private *dev_priv = to_i915(connector->dev);
        enum port port = dp_to_dig_port(intel_dp)->base.port;

        if (!IS_G4X(dev_priv) && port != PORT_A)
                intel_attach_force_audio_property(connector);

        intel_attach_broadcast_rgb_property(connector);
        if (HAS_GMCH(dev_priv))
                drm_connector_attach_max_bpc_property(connector, 6, 10);
        else if (INTEL_GEN(dev_priv) >= 5)
                drm_connector_attach_max_bpc_property(connector, 6, 12);

        intel_attach_colorspace_property(connector);

        if (IS_GEMINILAKE(dev_priv) || INTEL_GEN(dev_priv) >= 11)
                drm_object_attach_property(&connector->base,
                                           connector->dev->mode_config.hdr_output_metadata_property,
                                           0);

        if (intel_dp_is_edp(intel_dp)) {
                u32 allowed_scalers;

                allowed_scalers = BIT(DRM_MODE_SCALE_ASPECT) | BIT(DRM_MODE_SCALE_FULLSCREEN);
                if (!HAS_GMCH(dev_priv))
                        allowed_scalers |= BIT(DRM_MODE_SCALE_CENTER);

                drm_connector_attach_scaling_mode_property(connector, allowed_scalers);

                connector->state->scaling_mode = DRM_MODE_SCALE_ASPECT;

        }
}

static void intel_dp_init_panel_power_timestamps(struct intel_dp *intel_dp)
{
        intel_dp->panel_power_off_time = ktime_get_boottime();
        intel_dp->last_power_on = jiffies;
        intel_dp->last_backlight_off = jiffies;
}

static void
intel_pps_readout_hw_state(struct intel_dp *intel_dp, struct edp_power_seq *seq)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        u32 pp_on, pp_off, pp_ctl;
        struct pps_registers regs;

        intel_pps_get_registers(intel_dp, &regs);

        pp_ctl = ironlake_get_pp_control(intel_dp);

        /* Ensure PPS is unlocked */
        if (!HAS_DDI(dev_priv))
                I915_WRITE(regs.pp_ctrl, pp_ctl);

        pp_on = I915_READ(regs.pp_on);
        pp_off = I915_READ(regs.pp_off);

        /* Pull timing values out of registers */
        seq->t1_t3 = REG_FIELD_GET(PANEL_POWER_UP_DELAY_MASK, pp_on);
        seq->t8 = REG_FIELD_GET(PANEL_LIGHT_ON_DELAY_MASK, pp_on);
        seq->t9 = REG_FIELD_GET(PANEL_LIGHT_OFF_DELAY_MASK, pp_off);
        seq->t10 = REG_FIELD_GET(PANEL_POWER_DOWN_DELAY_MASK, pp_off);

        if (i915_mmio_reg_valid(regs.pp_div)) {
                u32 pp_div;

                pp_div = I915_READ(regs.pp_div);

                seq->t11_t12 = REG_FIELD_GET(PANEL_POWER_CYCLE_DELAY_MASK, pp_div) * 1000;
        } else {
                seq->t11_t12 = REG_FIELD_GET(BXT_POWER_CYCLE_DELAY_MASK, pp_ctl) * 1000;
        }
}

static void
intel_pps_dump_state(const char *state_name, const struct edp_power_seq *seq)
{
        DRM_DEBUG_KMS("%s t1_t3 %d t8 %d t9 %d t10 %d t11_t12 %d\n",
                      state_name,
                      seq->t1_t3, seq->t8, seq->t9, seq->t10, seq->t11_t12);
}

static void
intel_pps_verify_state(struct intel_dp *intel_dp)
{
        struct edp_power_seq hw;
        struct edp_power_seq *sw = &intel_dp->pps_delays;

        intel_pps_readout_hw_state(intel_dp, &hw);

        if (hw.t1_t3 != sw->t1_t3 || hw.t8 != sw->t8 || hw.t9 != sw->t9 ||
            hw.t10 != sw->t10 || hw.t11_t12 != sw->t11_t12) {
                DRM_ERROR("PPS state mismatch\n");
                intel_pps_dump_state("sw", sw);
                intel_pps_dump_state("hw", &hw);
        }
}

static void
intel_dp_init_panel_power_sequencer(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct edp_power_seq cur, vbt, spec,
                *final = &intel_dp->pps_delays;

        lockdep_assert_held(&dev_priv->pps_mutex);

        /* already initialized? */
        if (final->t11_t12 != 0)
                return;

        intel_pps_readout_hw_state(intel_dp, &cur);

        intel_pps_dump_state("cur", &cur);

        vbt = dev_priv->vbt.edp.pps;
        /* On Toshiba Satellite P50-C-18C system the VBT T12 delay
         * of 500ms appears to be too short. Ocassionally the panel
         * just fails to power back on. Increasing the delay to 800ms
         * seems sufficient to avoid this problem.
         */
        if (dev_priv->quirks & QUIRK_INCREASE_T12_DELAY) {
                vbt.t11_t12 = max_t(u16, vbt.t11_t12, 1300 * 10);
                DRM_DEBUG_KMS("Increasing T12 panel delay as per the quirk to %d\n",
                              vbt.t11_t12);
        }
        /* T11_T12 delay is special and actually in units of 100ms, but zero
         * based in the hw (so we need to add 100 ms). But the sw vbt
         * table multiplies it with 1000 to make it in units of 100usec,
         * too. */
        vbt.t11_t12 += 100 * 10;

        /* Upper limits from eDP 1.3 spec. Note that we use the clunky units of
         * our hw here, which are all in 100usec. */
        spec.t1_t3 = 210 * 10;
        spec.t8 = 50 * 10; /* no limit for t8, use t7 instead */
        spec.t9 = 50 * 10; /* no limit for t9, make it symmetric with t8 */
        spec.t10 = 500 * 10;
        /* This one is special and actually in units of 100ms, but zero
         * based in the hw (so we need to add 100 ms). But the sw vbt
         * table multiplies it with 1000 to make it in units of 100usec,
         * too. */
        spec.t11_t12 = (510 + 100) * 10;

        intel_pps_dump_state("vbt", &vbt);

        /* Use the max of the register settings and vbt. If both are
         * unset, fall back to the spec limits. */
#define assign_final(field)     final->field = (max(cur.field, vbt.field) == 0 ? \
                                       spec.field : \
                                       max(cur.field, vbt.field))
        assign_final(t1_t3);
        assign_final(t8);
        assign_final(t9);
        assign_final(t10);
        assign_final(t11_t12);
#undef assign_final

#define get_delay(field)        (DIV_ROUND_UP(final->field, 10))
        intel_dp->panel_power_up_delay = get_delay(t1_t3);
        intel_dp->backlight_on_delay = get_delay(t8);
        intel_dp->backlight_off_delay = get_delay(t9);
        intel_dp->panel_power_down_delay = get_delay(t10);
        intel_dp->panel_power_cycle_delay = get_delay(t11_t12);
#undef get_delay

        DRM_DEBUG_KMS("panel power up delay %d, power down delay %d, power cycle delay %d\n",
                      intel_dp->panel_power_up_delay, intel_dp->panel_power_down_delay,
                      intel_dp->panel_power_cycle_delay);

        DRM_DEBUG_KMS("backlight on delay %d, off delay %d\n",
                      intel_dp->backlight_on_delay, intel_dp->backlight_off_delay);

        /*
         * We override the HW backlight delays to 1 because we do manual waits
         * on them. For T8, even BSpec recommends doing it. For T9, if we
         * don't do this, we'll end up waiting for the backlight off delay
         * twice: once when we do the manual sleep, and once when we disable
         * the panel and wait for the PP_STATUS bit to become zero.
         */
        final->t8 = 1;
        final->t9 = 1;

        /*
         * HW has only a 100msec granularity for t11_t12 so round it up
         * accordingly.
         */
        final->t11_t12 = roundup(final->t11_t12, 100 * 10);
}

static void
intel_dp_init_panel_power_sequencer_registers(struct intel_dp *intel_dp,
                                              bool force_disable_vdd)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        u32 pp_on, pp_off, port_sel = 0;
        int div = dev_priv->rawclk_freq / 1000;
        struct pps_registers regs;
        enum port port = dp_to_dig_port(intel_dp)->base.port;
        const struct edp_power_seq *seq = &intel_dp->pps_delays;

        lockdep_assert_held(&dev_priv->pps_mutex);

        intel_pps_get_registers(intel_dp, &regs);

        /*
         * On some VLV machines the BIOS can leave the VDD
         * enabled even on power sequencers which aren't
         * hooked up to any port. This would mess up the
         * power domain tracking the first time we pick
         * one of these power sequencers for use since
         * edp_panel_vdd_on() would notice that the VDD was
         * already on and therefore wouldn't grab the power
         * domain reference. Disable VDD first to avoid this.
         * This also avoids spuriously turning the VDD on as
         * soon as the new power sequencer gets initialized.
         */
        if (force_disable_vdd) {
                u32 pp = ironlake_get_pp_control(intel_dp);

                WARN(pp & PANEL_POWER_ON, "Panel power already on\n");

                if (pp & EDP_FORCE_VDD)
                        DRM_DEBUG_KMS("VDD already on, disabling first\n");

                pp &= ~EDP_FORCE_VDD;

                I915_WRITE(regs.pp_ctrl, pp);
        }

        pp_on = REG_FIELD_PREP(PANEL_POWER_UP_DELAY_MASK, seq->t1_t3) |
                REG_FIELD_PREP(PANEL_LIGHT_ON_DELAY_MASK, seq->t8);
        pp_off = REG_FIELD_PREP(PANEL_LIGHT_OFF_DELAY_MASK, seq->t9) |
                REG_FIELD_PREP(PANEL_POWER_DOWN_DELAY_MASK, seq->t10);

        /* Haswell doesn't have any port selection bits for the panel
         * power sequencer any more. */
        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                port_sel = PANEL_PORT_SELECT_VLV(port);
        } else if (HAS_PCH_IBX(dev_priv) || HAS_PCH_CPT(dev_priv)) {
                switch (port) {
                case PORT_A:
                        port_sel = PANEL_PORT_SELECT_DPA;
                        break;
                case PORT_C:
                        port_sel = PANEL_PORT_SELECT_DPC;
                        break;
                case PORT_D:
                        port_sel = PANEL_PORT_SELECT_DPD;
                        break;
                default:
                        MISSING_CASE(port);
                        break;
                }
        }

        pp_on |= port_sel;

        I915_WRITE(regs.pp_on, pp_on);
        I915_WRITE(regs.pp_off, pp_off);

        /*
         * Compute the divisor for the pp clock, simply match the Bspec formula.
         */
        if (i915_mmio_reg_valid(regs.pp_div)) {
                I915_WRITE(regs.pp_div,
                           REG_FIELD_PREP(PP_REFERENCE_DIVIDER_MASK, (100 * div) / 2 - 1) |
                           REG_FIELD_PREP(PANEL_POWER_CYCLE_DELAY_MASK, DIV_ROUND_UP(seq->t11_t12, 1000)));
        } else {
                u32 pp_ctl;

                pp_ctl = I915_READ(regs.pp_ctrl);
                pp_ctl &= ~BXT_POWER_CYCLE_DELAY_MASK;
                pp_ctl |= REG_FIELD_PREP(BXT_POWER_CYCLE_DELAY_MASK, DIV_ROUND_UP(seq->t11_t12, 1000));
                I915_WRITE(regs.pp_ctrl, pp_ctl);
        }

        DRM_DEBUG_KMS("panel power sequencer register settings: PP_ON %#x, PP_OFF %#x, PP_DIV %#x\n",
                      I915_READ(regs.pp_on),
                      I915_READ(regs.pp_off),
                      i915_mmio_reg_valid(regs.pp_div) ?
                      I915_READ(regs.pp_div) :
                      (I915_READ(regs.pp_ctrl) & BXT_POWER_CYCLE_DELAY_MASK));
}

static void intel_dp_pps_init(struct intel_dp *intel_dp)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                vlv_initial_power_sequencer_setup(intel_dp);
        } else {
                intel_dp_init_panel_power_sequencer(intel_dp);
                intel_dp_init_panel_power_sequencer_registers(intel_dp, false);
        }
}

/**
 * intel_dp_set_drrs_state - program registers for RR switch to take effect
 * @dev_priv: i915 device
 * @crtc_state: a pointer to the active intel_crtc_state
 * @refresh_rate: RR to be programmed
 *
 * This function gets called when refresh rate (RR) has to be changed from
 * one frequency to another. Switches can be between high and low RR
 * supported by the panel or to any other RR based on media playback (in
 * this case, RR value needs to be passed from user space).
 *
 * The caller of this function needs to take a lock on dev_priv->drrs.
 */
static void intel_dp_set_drrs_state(struct drm_i915_private *dev_priv,
                                    const struct intel_crtc_state *crtc_state,
                                    int refresh_rate)
{
        struct intel_dp *intel_dp = dev_priv->drrs.dp;
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
        enum drrs_refresh_rate_type index = DRRS_HIGH_RR;

        if (refresh_rate <= 0) {
                DRM_DEBUG_KMS("Refresh rate should be positive non-zero.\n");
                return;
        }

        if (intel_dp == NULL) {
                DRM_DEBUG_KMS("DRRS not supported.\n");
                return;
        }

        if (!intel_crtc) {
                DRM_DEBUG_KMS("DRRS: intel_crtc not initialized\n");
                return;
        }

        if (dev_priv->drrs.type < SEAMLESS_DRRS_SUPPORT) {
                DRM_DEBUG_KMS("Only Seamless DRRS supported.\n");
                return;
        }

        if (intel_dp->attached_connector->panel.downclock_mode->vrefresh ==
                        refresh_rate)
                index = DRRS_LOW_RR;

        if (index == dev_priv->drrs.refresh_rate_type) {
                DRM_DEBUG_KMS(
                        "DRRS requested for previously set RR...ignoring\n");
                return;
        }

        if (!crtc_state->base.active) {
                DRM_DEBUG_KMS("eDP encoder disabled. CRTC not Active\n");
                return;
        }

        if (INTEL_GEN(dev_priv) >= 8 && !IS_CHERRYVIEW(dev_priv)) {
                switch (index) {
                case DRRS_HIGH_RR:
                        intel_dp_set_m_n(crtc_state, M1_N1);
                        break;
                case DRRS_LOW_RR:
                        intel_dp_set_m_n(crtc_state, M2_N2);
                        break;
                case DRRS_MAX_RR:
                default:
                        DRM_ERROR("Unsupported refreshrate type\n");
                }
        } else if (INTEL_GEN(dev_priv) > 6) {
                i915_reg_t reg = PIPECONF(crtc_state->cpu_transcoder);
                u32 val;

                val = I915_READ(reg);
                if (index > DRRS_HIGH_RR) {
                        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                                val |= PIPECONF_EDP_RR_MODE_SWITCH_VLV;
                        else
                                val |= PIPECONF_EDP_RR_MODE_SWITCH;
                } else {
                        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                                val &= ~PIPECONF_EDP_RR_MODE_SWITCH_VLV;
                        else
                                val &= ~PIPECONF_EDP_RR_MODE_SWITCH;
                }
                I915_WRITE(reg, val);
        }

        dev_priv->drrs.refresh_rate_type = index;

        DRM_DEBUG_KMS("eDP Refresh Rate set to : %dHz\n", refresh_rate);
}

/**
 * intel_edp_drrs_enable - init drrs struct if supported
 * @intel_dp: DP struct
 * @crtc_state: A pointer to the active crtc state.
 *
 * Initializes frontbuffer_bits and drrs.dp
 */
void intel_edp_drrs_enable(struct intel_dp *intel_dp,
                           const struct intel_crtc_state *crtc_state)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        if (!crtc_state->has_drrs) {
                DRM_DEBUG_KMS("Panel doesn't support DRRS\n");
                return;
        }

        if (dev_priv->psr.enabled) {
                DRM_DEBUG_KMS("PSR enabled. Not enabling DRRS.\n");
                return;
        }

        mutex_lock(&dev_priv->drrs.mutex);
        if (dev_priv->drrs.dp) {
                DRM_DEBUG_KMS("DRRS already enabled\n");
                goto unlock;
        }

        dev_priv->drrs.busy_frontbuffer_bits = 0;

        dev_priv->drrs.dp = intel_dp;

unlock:
        mutex_unlock(&dev_priv->drrs.mutex);
}

/**
 * intel_edp_drrs_disable - Disable DRRS
 * @intel_dp: DP struct
 * @old_crtc_state: Pointer to old crtc_state.
 *
 */
void intel_edp_drrs_disable(struct intel_dp *intel_dp,
                            const struct intel_crtc_state *old_crtc_state)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);

        if (!old_crtc_state->has_drrs)
                return;

        mutex_lock(&dev_priv->drrs.mutex);
        if (!dev_priv->drrs.dp) {
                mutex_unlock(&dev_priv->drrs.mutex);
                return;
        }

        if (dev_priv->drrs.refresh_rate_type == DRRS_LOW_RR)
                intel_dp_set_drrs_state(dev_priv, old_crtc_state,
                        intel_dp->attached_connector->panel.fixed_mode->vrefresh);

        dev_priv->drrs.dp = NULL;
        mutex_unlock(&dev_priv->drrs.mutex);

        cancel_delayed_work_sync(&dev_priv->drrs.work);
}

static void intel_edp_drrs_downclock_work(struct work_struct *work)
{
        struct drm_i915_private *dev_priv =
                container_of(work, typeof(*dev_priv), drrs.work.work);
        struct intel_dp *intel_dp;

        mutex_lock(&dev_priv->drrs.mutex);

        intel_dp = dev_priv->drrs.dp;

        if (!intel_dp)
                goto unlock;

        /*
         * The delayed work can race with an invalidate hence we need to
         * recheck.
         */

        if (dev_priv->drrs.busy_frontbuffer_bits)
                goto unlock;

        if (dev_priv->drrs.refresh_rate_type != DRRS_LOW_RR) {
                struct drm_crtc *crtc = dp_to_dig_port(intel_dp)->base.base.crtc;

                intel_dp_set_drrs_state(dev_priv, to_intel_crtc(crtc)->config,
                        intel_dp->attached_connector->panel.downclock_mode->vrefresh);
        }

unlock:
        mutex_unlock(&dev_priv->drrs.mutex);
}

/**
 * intel_edp_drrs_invalidate - Disable Idleness DRRS
 * @dev_priv: i915 device
 * @frontbuffer_bits: frontbuffer plane tracking bits
 *
 * This function gets called everytime rendering on the given planes start.
 * Hence DRRS needs to be Upclocked, i.e. (LOW_RR -> HIGH_RR).
 *
 * Dirty frontbuffers relevant to DRRS are tracked in busy_frontbuffer_bits.
 */
void intel_edp_drrs_invalidate(struct drm_i915_private *dev_priv,
                               unsigned int frontbuffer_bits)
{
        struct drm_crtc *crtc;
        enum pipe pipe;

        if (dev_priv->drrs.type == DRRS_NOT_SUPPORTED)
                return;

        cancel_delayed_work(&dev_priv->drrs.work);

        mutex_lock(&dev_priv->drrs.mutex);
        if (!dev_priv->drrs.dp) {
                mutex_unlock(&dev_priv->drrs.mutex);
                return;
        }

        crtc = dp_to_dig_port(dev_priv->drrs.dp)->base.base.crtc;
        pipe = to_intel_crtc(crtc)->pipe;

        frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);
        dev_priv->drrs.busy_frontbuffer_bits |= frontbuffer_bits;

        /* invalidate means busy screen hence upclock */
        if (frontbuffer_bits && dev_priv->drrs.refresh_rate_type == DRRS_LOW_RR)
                intel_dp_set_drrs_state(dev_priv, to_intel_crtc(crtc)->config,
                        dev_priv->drrs.dp->attached_connector->panel.fixed_mode->vrefresh);

        mutex_unlock(&dev_priv->drrs.mutex);
}

/**
 * intel_edp_drrs_flush - Restart Idleness DRRS
 * @dev_priv: i915 device
 * @frontbuffer_bits: frontbuffer plane tracking bits
 *
 * This function gets called every time rendering on the given planes has
 * completed or flip on a crtc is completed. So DRRS should be upclocked
 * (LOW_RR -> HIGH_RR). And also Idleness detection should be started again,
 * if no other planes are dirty.
 *
 * Dirty frontbuffers relevant to DRRS are tracked in busy_frontbuffer_bits.
 */
void intel_edp_drrs_flush(struct drm_i915_private *dev_priv,
                          unsigned int frontbuffer_bits)
{
        struct drm_crtc *crtc;
        enum pipe pipe;

        if (dev_priv->drrs.type == DRRS_NOT_SUPPORTED)
                return;

        cancel_delayed_work(&dev_priv->drrs.work);

        mutex_lock(&dev_priv->drrs.mutex);
        if (!dev_priv->drrs.dp) {
                mutex_unlock(&dev_priv->drrs.mutex);
                return;
        }

        crtc = dp_to_dig_port(dev_priv->drrs.dp)->base.base.crtc;
        pipe = to_intel_crtc(crtc)->pipe;

        frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe);
        dev_priv->drrs.busy_frontbuffer_bits &= ~frontbuffer_bits;

        /* flush means busy screen hence upclock */
        if (frontbuffer_bits && dev_priv->drrs.refresh_rate_type == DRRS_LOW_RR)
                intel_dp_set_drrs_state(dev_priv, to_intel_crtc(crtc)->config,
                                dev_priv->drrs.dp->attached_connector->panel.fixed_mode->vrefresh);

        /*
         * flush also means no more activity hence schedule downclock, if all
         * other fbs are quiescent too
         */
        if (!dev_priv->drrs.busy_frontbuffer_bits)
                schedule_delayed_work(&dev_priv->drrs.work,
                                msecs_to_jiffies(1000));
        mutex_unlock(&dev_priv->drrs.mutex);
}

/**
 * DOC: Display Refresh Rate Switching (DRRS)
 *
 * Display Refresh Rate Switching (DRRS) is a power conservation feature
 * which enables swtching between low and high refresh rates,
 * dynamically, based on the usage scenario. This feature is applicable
 * for internal panels.
 *
 * Indication that the panel supports DRRS is given by the panel EDID, which
 * would list multiple refresh rates for one resolution.
 *
 * DRRS is of 2 types - static and seamless.
 * Static DRRS involves changing refresh rate (RR) by doing a full modeset
 * (may appear as a blink on screen) and is used in dock-undock scenario.
 * Seamless DRRS involves changing RR without any visual effect to the user
 * and can be used during normal system usage. This is done by programming
 * certain registers.
 *
 * Support for static/seamless DRRS may be indicated in the VBT based on
 * inputs from the panel spec.
 *
 * DRRS saves power by switching to low RR based on usage scenarios.
 *
 * The implementation is based on frontbuffer tracking implementation.  When
 * there is a disturbance on the screen triggered by user activity or a periodic
 * system activity, DRRS is disabled (RR is changed to high RR).  When there is
 * no movement on screen, after a timeout of 1 second, a switch to low RR is
 * made.
 *
 * For integration with frontbuffer tracking code, intel_edp_drrs_invalidate()
 * and intel_edp_drrs_flush() are called.
 *
 * DRRS can be further extended to support other internal panels and also
 * the scenario of video playback wherein RR is set based on the rate
 * requested by userspace.
 */

/**
 * intel_dp_drrs_init - Init basic DRRS work and mutex.
 * @connector: eDP connector
 * @fixed_mode: preferred mode of panel
 *
 * This function is  called only once at driver load to initialize basic
 * DRRS stuff.
 *
 * Returns:
 * Downclock mode if panel supports it, else return NULL.
 * DRRS support is determined by the presence of downclock mode (apart
 * from VBT setting).
 */
static struct drm_display_mode *
intel_dp_drrs_init(struct intel_connector *connector,
                   struct drm_display_mode *fixed_mode)
{
        struct drm_i915_private *dev_priv = to_i915(connector->base.dev);
        struct drm_display_mode *downclock_mode = NULL;

        INIT_DELAYED_WORK(&dev_priv->drrs.work, intel_edp_drrs_downclock_work);
        mutex_init(&dev_priv->drrs.mutex);

        if (INTEL_GEN(dev_priv) <= 6) {
                DRM_DEBUG_KMS("DRRS supported for Gen7 and above\n");
                return NULL;
        }

        if (dev_priv->vbt.drrs_type != SEAMLESS_DRRS_SUPPORT) {
                DRM_DEBUG_KMS("VBT doesn't support DRRS\n");
                return NULL;
        }

        downclock_mode = intel_panel_edid_downclock_mode(connector, fixed_mode);
        if (!downclock_mode) {
                DRM_DEBUG_KMS("Downclock mode is not found. DRRS not supported\n");
                return NULL;
        }

        dev_priv->drrs.type = dev_priv->vbt.drrs_type;

        dev_priv->drrs.refresh_rate_type = DRRS_HIGH_RR;
        DRM_DEBUG_KMS("seamless DRRS supported for eDP panel.\n");
        return downclock_mode;
}

static bool intel_edp_init_connector(struct intel_dp *intel_dp,
                                     struct intel_connector *intel_connector)
{
        struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
        struct drm_device *dev = &dev_priv->drm;
        struct drm_connector *connector = &intel_connector->base;
        struct drm_display_mode *fixed_mode = NULL;
        struct drm_display_mode *downclock_mode = NULL;
        bool has_dpcd;
        enum pipe pipe = INVALID_PIPE;
        intel_wakeref_t wakeref;
        struct edid *edid;

        if (!intel_dp_is_edp(intel_dp))
                return true;

        INIT_DELAYED_WORK(&intel_dp->panel_vdd_work, edp_panel_vdd_work);

        /*
         * On IBX/CPT we may get here with LVDS already registered. Since the
         * driver uses the only internal power sequencer available for both
         * eDP and LVDS bail out early in this case to prevent interfering
         * with an already powered-on LVDS power sequencer.
         */
        if (intel_get_lvds_encoder(dev_priv)) {
                WARN_ON(!(HAS_PCH_IBX(dev_priv) || HAS_PCH_CPT(dev_priv)));
                DRM_INFO("LVDS was detected, not registering eDP\n");

                return false;
        }

        with_pps_lock(intel_dp, wakeref) {
                intel_dp_init_panel_power_timestamps(intel_dp);
                intel_dp_pps_init(intel_dp);
                intel_edp_panel_vdd_sanitize(intel_dp);
        }

        /* Cache DPCD and EDID for edp. */
        has_dpcd = intel_edp_init_dpcd(intel_dp);

        if (!has_dpcd) {
                /* if this fails, presume the device is a ghost */
                DRM_INFO("failed to retrieve link info, disabling eDP\n");
                goto out_vdd_off;
        }

        mutex_lock(&dev->mode_config.mutex);
        edid = drm_get_edid(connector, &intel_dp->aux.ddc);
        if (edid) {
                if (drm_add_edid_modes(connector, edid)) {
                        drm_connector_update_edid_property(connector,
                                                                edid);
                } else {
                        kfree(edid);
                        edid = ERR_PTR(-EINVAL);
                }
        } else {
                edid = ERR_PTR(-ENOENT);
        }
        intel_connector->edid = edid;

        fixed_mode = intel_panel_edid_fixed_mode(intel_connector);
        if (fixed_mode)
                downclock_mode = intel_dp_drrs_init(intel_connector, fixed_mode);

        /* fallback to VBT if available for eDP */
        if (!fixed_mode)
                fixed_mode = intel_panel_vbt_fixed_mode(intel_connector);
        mutex_unlock(&dev->mode_config.mutex);

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
                intel_dp->edp_notifier.notifier_call = edp_notify_handler;
                register_reboot_notifier(&intel_dp->edp_notifier);

                /*
                 * Figure out the current pipe for the initial backlight setup.
                 * If the current pipe isn't valid, try the PPS pipe, and if that
                 * fails just assume pipe A.
                 */
                pipe = vlv_active_pipe(intel_dp);

                if (pipe != PIPE_A && pipe != PIPE_B)
                        pipe = intel_dp->pps_pipe;

                if (pipe != PIPE_A && pipe != PIPE_B)
                        pipe = PIPE_A;

                DRM_DEBUG_KMS("using pipe %c for initial backlight setup\n",
                              pipe_name(pipe));
        }

        intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
        intel_connector->panel.backlight.power = intel_edp_backlight_power;
        intel_panel_setup_backlight(connector, pipe);

        if (fixed_mode)
                drm_connector_init_panel_orientation_property(
                        connector, fixed_mode->hdisplay, fixed_mode->vdisplay);

        return true;

out_vdd_off:
        cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
        /*
         * vdd might still be enabled do to the delayed vdd off.
         * Make sure vdd is actually turned off here.
         */
        with_pps_lock(intel_dp, wakeref)
                edp_panel_vdd_off_sync(intel_dp);

        return false;
}

static void intel_dp_modeset_retry_work_fn(struct work_struct *work)
{
        struct intel_connector *intel_connector;
        struct drm_connector *connector;

        intel_connector = container_of(work, typeof(*intel_connector),
                                       modeset_retry_work);
        connector = &intel_connector->base;
        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id,
                      connector->name);

        /* Grab the locks before changing connector property*/
        mutex_lock(&connector->dev->mode_config.mutex);
        /* Set connector link status to BAD and send a Uevent to notify
         * userspace to do a modeset.
         */
        drm_connector_set_link_status_property(connector,
                                               DRM_MODE_LINK_STATUS_BAD);
        mutex_unlock(&connector->dev->mode_config.mutex);
        /* Send Hotplug uevent so userspace can reprobe */
        drm_kms_helper_hotplug_event(connector->dev);
}

bool
intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
                        struct intel_connector *intel_connector)
{
        struct drm_connector *connector = &intel_connector->base;
        struct intel_dp *intel_dp = &intel_dig_port->dp;
        struct intel_encoder *intel_encoder = &intel_dig_port->base;
        struct drm_device *dev = intel_encoder->base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        enum port port = intel_encoder->port;
        enum phy phy = intel_port_to_phy(dev_priv, port);
        int type;

        /* Initialize the work for modeset in case of link train failure */
        INIT_WORK(&intel_connector->modeset_retry_work,
                  intel_dp_modeset_retry_work_fn);

        if (WARN(intel_dig_port->max_lanes < 1,
                 "Not enough lanes (%d) for DP on [ENCODER:%d:%s]\n",
                 intel_dig_port->max_lanes, intel_encoder->base.base.id,
                 intel_encoder->base.name))
                return false;

        intel_dp_set_source_rates(intel_dp);

        intel_dp->reset_link_params = true;
        intel_dp->pps_pipe = INVALID_PIPE;
        intel_dp->active_pipe = INVALID_PIPE;

        /* Preserve the current hw state. */
        intel_dp->DP = I915_READ(intel_dp->output_reg);
        intel_dp->attached_connector = intel_connector;

        if (intel_dp_is_port_edp(dev_priv, port)) {
                /*
                 * Currently we don't support eDP on TypeC ports, although in
                 * theory it could work on TypeC legacy ports.
                 */
                WARN_ON(intel_phy_is_tc(dev_priv, phy));
                type = DRM_MODE_CONNECTOR_eDP;
        } else {
                type = DRM_MODE_CONNECTOR_DisplayPort;
        }

        if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv))
                intel_dp->active_pipe = vlv_active_pipe(intel_dp);

        /*
         * For eDP we always set the encoder type to INTEL_OUTPUT_EDP, but
         * for DP the encoder type can be set by the caller to
         * INTEL_OUTPUT_UNKNOWN for DDI, so don't rewrite it.
         */
        if (type == DRM_MODE_CONNECTOR_eDP)
                intel_encoder->type = INTEL_OUTPUT_EDP;

        /* eDP only on port B and/or C on vlv/chv */
        if (WARN_ON((IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) &&
                    intel_dp_is_edp(intel_dp) &&
                    port != PORT_B && port != PORT_C))
                return false;

        DRM_DEBUG_KMS("Adding %s connector on [ENCODER:%d:%s]\n",
                      type == DRM_MODE_CONNECTOR_eDP ? "eDP" : "DP",
                      intel_encoder->base.base.id, intel_encoder->base.name);

        drm_connector_init(dev, connector, &intel_dp_connector_funcs, type);
        drm_connector_helper_add(connector, &intel_dp_connector_helper_funcs);

        if (!HAS_GMCH(dev_priv))
                connector->interlace_allowed = true;
        connector->doublescan_allowed = 0;

        if (INTEL_GEN(dev_priv) >= 11)
                connector->ycbcr_420_allowed = true;

        intel_encoder->hpd_pin = intel_hpd_pin_default(dev_priv, port);

        intel_dp_aux_init(intel_dp);

        intel_connector_attach_encoder(intel_connector, intel_encoder);

        if (HAS_DDI(dev_priv))
                intel_connector->get_hw_state = intel_ddi_connector_get_hw_state;
        else
                intel_connector->get_hw_state = intel_connector_get_hw_state;

        /* init MST on ports that can support it */
        intel_dp_mst_encoder_init(intel_dig_port,
                                  intel_connector->base.base.id);

        if (!intel_edp_init_connector(intel_dp, intel_connector)) {
                intel_dp_aux_fini(intel_dp);
                intel_dp_mst_encoder_cleanup(intel_dig_port);
                goto fail;
        }

        intel_dp_add_properties(intel_dp, connector);

        if (is_hdcp_supported(dev_priv, port) && !intel_dp_is_edp(intel_dp)) {
                int ret = intel_hdcp_init(intel_connector, &intel_dp_hdcp_shim);
                if (ret)
                        DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
        }

        /* For G4X desktop chip, PEG_BAND_GAP_DATA 3:0 must first be written
         * 0xd.  Failure to do so will result in spurious interrupts being
         * generated on the port when a cable is not attached.
         */
        if (IS_G45(dev_priv)) {
                u32 temp = I915_READ(PEG_BAND_GAP_DATA);
                I915_WRITE(PEG_BAND_GAP_DATA, (temp & ~0xf) | 0xd);
        }

        return true;

fail:
        drm_connector_cleanup(connector);

        return false;
}

bool intel_dp_init(struct drm_i915_private *dev_priv,
                   i915_reg_t output_reg,
                   enum port port)
{
        struct intel_digital_port *intel_dig_port;
        struct intel_encoder *intel_encoder;
        struct drm_encoder *encoder;
        struct intel_connector *intel_connector;

        intel_dig_port = kzalloc(sizeof(*intel_dig_port), GFP_KERNEL);
        if (!intel_dig_port)
                return false;

        intel_connector = intel_connector_alloc();
        if (!intel_connector)
                goto err_connector_alloc;

        intel_encoder = &intel_dig_port->base;
        encoder = &intel_encoder->base;

        if (drm_encoder_init(&dev_priv->drm, &intel_encoder->base,
                             &intel_dp_enc_funcs, DRM_MODE_ENCODER_TMDS,
                             "DP %c", port_name(port)))
                goto err_encoder_init;

        intel_encoder->hotplug = intel_dp_hotplug;
        intel_encoder->compute_config = intel_dp_compute_config;
        intel_encoder->get_hw_state = intel_dp_get_hw_state;
        intel_encoder->get_config = intel_dp_get_config;
        intel_encoder->update_pipe = intel_panel_update_backlight;
        intel_encoder->suspend = intel_dp_encoder_suspend;
        if (IS_CHERRYVIEW(dev_priv)) {
                intel_encoder->pre_pll_enable = chv_dp_pre_pll_enable;
                intel_encoder->pre_enable = chv_pre_enable_dp;
                intel_encoder->enable = vlv_enable_dp;
                intel_encoder->disable = vlv_disable_dp;
                intel_encoder->post_disable = chv_post_disable_dp;
                intel_encoder->post_pll_disable = chv_dp_post_pll_disable;
        } else if (IS_VALLEYVIEW(dev_priv)) {
                intel_encoder->pre_pll_enable = vlv_dp_pre_pll_enable;
                intel_encoder->pre_enable = vlv_pre_enable_dp;
                intel_encoder->enable = vlv_enable_dp;
                intel_encoder->disable = vlv_disable_dp;
                intel_encoder->post_disable = vlv_post_disable_dp;
        } else {
                intel_encoder->pre_enable = g4x_pre_enable_dp;
                intel_encoder->enable = g4x_enable_dp;
                intel_encoder->disable = g4x_disable_dp;
                intel_encoder->post_disable = g4x_post_disable_dp;
        }

        intel_dig_port->dp.output_reg = output_reg;
        intel_dig_port->max_lanes = 4;

        intel_encoder->type = INTEL_OUTPUT_DP;
        intel_encoder->power_domain = intel_port_to_power_domain(port);
        if (IS_CHERRYVIEW(dev_priv)) {
                if (port == PORT_D)
                        intel_encoder->pipe_mask = BIT(PIPE_C);
                else
                        intel_encoder->pipe_mask = BIT(PIPE_A) | BIT(PIPE_B);
        } else {
                intel_encoder->pipe_mask = ~0;
        }
        intel_encoder->cloneable = 0;
        intel_encoder->port = port;

        intel_dig_port->hpd_pulse = intel_dp_hpd_pulse;

        if (port != PORT_A)
                intel_infoframe_init(intel_dig_port);

        intel_dig_port->aux_ch = intel_bios_port_aux_ch(dev_priv, port);
        if (!intel_dp_init_connector(intel_dig_port, intel_connector))
                goto err_init_connector;

        return true;

err_init_connector:
        drm_encoder_cleanup(encoder);
err_encoder_init:
        kfree(intel_connector);
err_connector_alloc:
        kfree(intel_dig_port);
        return false;
}

void intel_dp_mst_suspend(struct drm_i915_private *dev_priv)
{
        struct intel_encoder *encoder;

        for_each_intel_encoder(&dev_priv->drm, encoder) {
                struct intel_dp *intel_dp;

                if (encoder->type != INTEL_OUTPUT_DDI)
                        continue;

                intel_dp = enc_to_intel_dp(&encoder->base);

                if (!intel_dp->can_mst)
                        continue;

                if (intel_dp->is_mst)
                        drm_dp_mst_topology_mgr_suspend(&intel_dp->mst_mgr);
        }
}

void intel_dp_mst_resume(struct drm_i915_private *dev_priv)
{
        struct intel_encoder *encoder;

        for_each_intel_encoder(&dev_priv->drm, encoder) {
                struct intel_dp *intel_dp;
                int ret;

                if (encoder->type != INTEL_OUTPUT_DDI)
                        continue;

                intel_dp = enc_to_intel_dp(&encoder->base);

                if (!intel_dp->can_mst)
                        continue;

                ret = drm_dp_mst_topology_mgr_resume(&intel_dp->mst_mgr,
                                                     true);
                if (ret) {
                        intel_dp->is_mst = false;
                        drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
                                                        false);
                }
        }
}