drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 // Copyright 2018 IBM Corporation
   3
   4 #include <linux/clk.h>
   5 #include <linux/reset.h>
   6 #include <linux/regmap.h>
   7
   8 #include <drm/drm_crtc_helper.h>
   9 #include <drm/drm_device.h>
  10 #include <drm/drm_fb_cma_helper.h>
  11 #include <drm/drm_fourcc.h>
  12 #include <drm/drm_gem_cma_helper.h>
  13 #include <drm/drm_gem_framebuffer_helper.h>
  14 #include <drm/drm_panel.h>
  15 #include <drm/drm_simple_kms_helper.h>
  16 #include <drm/drm_vblank.h>
  17
  18 #include "aspeed_gfx.h"
  19
  20 static struct aspeed_gfx *
  21 drm_pipe_to_aspeed_gfx(struct drm_simple_display_pipe *pipe)
  22 {
  23         return container_of(pipe, struct aspeed_gfx, pipe);
  24 }
  25
  26 static int aspeed_gfx_set_pixel_fmt(struct aspeed_gfx *priv, u32 *bpp)
  27 {
  28         struct drm_crtc *crtc = &priv->pipe.crtc;
  29         struct drm_device *drm = crtc->dev;
  30         const u32 format = crtc->primary->state->fb->format->format;
  31         u32 ctrl1;
  32
  33         ctrl1 = readl(priv->base + CRT_CTRL1);
  34         ctrl1 &= ~CRT_CTRL_COLOR_MASK;
  35
  36         switch (format) {
  37         case DRM_FORMAT_RGB565:
  38                 dev_dbg(drm->dev, "Setting up RGB565 mode\n");
  39                 ctrl1 |= CRT_CTRL_COLOR_RGB565;
  40                 *bpp = 16;
  41                 break;
  42         case DRM_FORMAT_XRGB8888:
  43                 dev_dbg(drm->dev, "Setting up XRGB8888 mode\n");
  44                 ctrl1 |= CRT_CTRL_COLOR_XRGB8888;
  45                 *bpp = 32;
  46                 break;
  47         default:
  48                 dev_err(drm->dev, "Unhandled pixel format %08x\n", format);
  49                 return -EINVAL;
  50         }
  51
  52         writel(ctrl1, priv->base + CRT_CTRL1);
  53
  54         return 0;
  55 }
  56
  57 static void aspeed_gfx_enable_controller(struct aspeed_gfx *priv)
  58 {
  59         u32 ctrl1 = readl(priv->base + CRT_CTRL1);
  60         u32 ctrl2 = readl(priv->base + CRT_CTRL2);
  61
  62         /* SCU2C: set DAC source for display output to Graphics CRT (GFX) */
  63         regmap_update_bits(priv->scu, 0x2c, BIT(16), BIT(16));
  64
  65         writel(ctrl1 | CRT_CTRL_EN, priv->base + CRT_CTRL1);
  66         writel(ctrl2 | CRT_CTRL_DAC_EN, priv->base + CRT_CTRL2);
  67 }
  68
  69 static void aspeed_gfx_disable_controller(struct aspeed_gfx *priv)
  70 {
  71         u32 ctrl1 = readl(priv->base + CRT_CTRL1);
  72         u32 ctrl2 = readl(priv->base + CRT_CTRL2);
  73
  74         writel(ctrl1 & ~CRT_CTRL_EN, priv->base + CRT_CTRL1);
  75         writel(ctrl2 & ~CRT_CTRL_DAC_EN, priv->base + CRT_CTRL2);
  76
  77         regmap_update_bits(priv->scu, 0x2c, BIT(16), 0);
  78 }
  79
  80 static void aspeed_gfx_crtc_mode_set_nofb(struct aspeed_gfx *priv)
  81 {
  82         struct drm_display_mode *m = &priv->pipe.crtc.state->adjusted_mode;
  83         u32 ctrl1, d_offset, t_count, bpp;
  84         int err;
  85
  86         err = aspeed_gfx_set_pixel_fmt(priv, &bpp);
  87         if (err)
  88                 return;
  89
  90 #if 0
  91         /* TODO: we have only been able to test with the 40MHz USB clock. The
  92          * clock is fixed, so we cannot adjust it here. */
  93         clk_set_rate(priv->pixel_clk, m->crtc_clock * 1000);
  94 #endif
  95
  96         ctrl1 = readl(priv->base + CRT_CTRL1);
  97         ctrl1 &= ~(CRT_CTRL_INTERLACED |
  98                         CRT_CTRL_HSYNC_NEGATIVE |
  99                         CRT_CTRL_VSYNC_NEGATIVE);
 100
 101         if (m->flags & DRM_MODE_FLAG_INTERLACE)
 102                 ctrl1 |= CRT_CTRL_INTERLACED;
 103
 104         if (!(m->flags & DRM_MODE_FLAG_PHSYNC))
 105                 ctrl1 |= CRT_CTRL_HSYNC_NEGATIVE;
 106
 107         if (!(m->flags & DRM_MODE_FLAG_PVSYNC))
 108                 ctrl1 |= CRT_CTRL_VSYNC_NEGATIVE;
 109
 110         writel(ctrl1, priv->base + CRT_CTRL1);
 111
 112         /* Horizontal timing */
 113         writel(CRT_H_TOTAL(m->htotal - 1) | CRT_H_DE(m->hdisplay - 1),
 114                         priv->base + CRT_HORIZ0);
 115         writel(CRT_H_RS_START(m->hsync_start - 1) | CRT_H_RS_END(m->hsync_end),
 116                         priv->base + CRT_HORIZ1);
 117
 118
 119         /* Vertical timing */
 120         writel(CRT_V_TOTAL(m->vtotal - 1) | CRT_V_DE(m->vdisplay - 1),
 121                         priv->base + CRT_VERT0);
 122         writel(CRT_V_RS_START(m->vsync_start) | CRT_V_RS_END(m->vsync_end),
 123                         priv->base + CRT_VERT1);
 124
 125         /*
 126          * Display Offset: address difference between consecutive scan lines
 127          * Terminal Count: memory size of one scan line
 128          */
 129         d_offset = m->hdisplay * bpp / 8;
 130         t_count = (m->hdisplay * bpp + 127) / 128;
 131         writel(CRT_DISP_OFFSET(d_offset) | CRT_TERM_COUNT(t_count),
 132                         priv->base + CRT_OFFSET);
 133
 134         /*
 135          * Threshold: FIFO thresholds of refill and stop (16 byte chunks
 136          * per line, rounded up)
 137          */
 138         writel(G5_CRT_THROD_VAL, priv->base + CRT_THROD);
 139 }
 140
 141 static void aspeed_gfx_pipe_enable(struct drm_simple_display_pipe *pipe,
 142                               struct drm_crtc_state *crtc_state,
 143                               struct drm_plane_state *plane_state)
 144 {
 145         struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
 146         struct drm_crtc *crtc = &pipe->crtc;
 147
 148         aspeed_gfx_crtc_mode_set_nofb(priv);
 149         aspeed_gfx_enable_controller(priv);
 150         drm_crtc_vblank_on(crtc);
 151 }
 152
 153 static void aspeed_gfx_pipe_disable(struct drm_simple_display_pipe *pipe)
 154 {
 155         struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
 156         struct drm_crtc *crtc = &pipe->crtc;
 157
 158         drm_crtc_vblank_off(crtc);
 159         aspeed_gfx_disable_controller(priv);
 160 }
 161
 162 static void aspeed_gfx_pipe_update(struct drm_simple_display_pipe *pipe,
 163                                    struct drm_plane_state *plane_state)
 164 {
 165         struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
 166         struct drm_crtc *crtc = &pipe->crtc;
 167         struct drm_framebuffer *fb = pipe->plane.state->fb;
 168         struct drm_pending_vblank_event *event;
 169         struct drm_gem_cma_object *gem;
 170
 171         spin_lock_irq(&crtc->dev->event_lock);
 172         event = crtc->state->event;
 173         if (event) {
 174                 crtc->state->event = NULL;
 175
 176                 if (drm_crtc_vblank_get(crtc) == 0)
 177                         drm_crtc_arm_vblank_event(crtc, event);
 178                 else
 179                         drm_crtc_send_vblank_event(crtc, event);
 180         }
 181         spin_unlock_irq(&crtc->dev->event_lock);
 182
 183         if (!fb)
 184                 return;
 185
 186         gem = drm_fb_cma_get_gem_obj(fb, 0);
 187         if (!gem)
 188                 return;
 189         writel(gem->paddr, priv->base + CRT_ADDR);
 190 }
 191
 192 static int aspeed_gfx_enable_vblank(struct drm_simple_display_pipe *pipe)
 193 {
 194         struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
 195         u32 reg = readl(priv->base + CRT_CTRL1);
 196
 197         /* Clear pending VBLANK IRQ */
 198         writel(reg | CRT_CTRL_VERTICAL_INTR_STS, priv->base + CRT_CTRL1);
 199
 200         reg |= CRT_CTRL_VERTICAL_INTR_EN;
 201         writel(reg, priv->base + CRT_CTRL1);
 202
 203         return 0;
 204 }
 205
 206 static void aspeed_gfx_disable_vblank(struct drm_simple_display_pipe *pipe)
 207 {
 208         struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
 209         u32 reg = readl(priv->base + CRT_CTRL1);
 210
 211         reg &= ~CRT_CTRL_VERTICAL_INTR_EN;
 212         writel(reg, priv->base + CRT_CTRL1);
 213
 214         /* Clear pending VBLANK IRQ */
 215         writel(reg | CRT_CTRL_VERTICAL_INTR_STS, priv->base + CRT_CTRL1);
 216 }
 217
 218 static struct drm_simple_display_pipe_funcs aspeed_gfx_funcs = {
 219         .enable         = aspeed_gfx_pipe_enable,
 220         .disable        = aspeed_gfx_pipe_disable,
 221         .update         = aspeed_gfx_pipe_update,
 222         .prepare_fb     = drm_gem_fb_simple_display_pipe_prepare_fb,
 223         .enable_vblank  = aspeed_gfx_enable_vblank,
 224         .disable_vblank = aspeed_gfx_disable_vblank,
 225 };
 226
 227 static const uint32_t aspeed_gfx_formats[] = {
 228         DRM_FORMAT_XRGB8888,
 229         DRM_FORMAT_RGB565,
 230 };
 231
 232 int aspeed_gfx_create_pipe(struct drm_device *drm)
 233 {
 234         struct aspeed_gfx *priv = drm->dev_private;
 235
 236         return drm_simple_display_pipe_init(drm, &priv->pipe, &aspeed_gfx_funcs,
 237                                             aspeed_gfx_formats,
 238                                             ARRAY_SIZE(aspeed_gfx_formats),
 239                                             NULL,
 240                                             &priv->connector);
 241 }