drivers/gpu/drm/sti/sti_dvo.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) STMicroelectronics SA 2014
   4  * Author: Vincent Abriou <vincent.abriou@st.com> for STMicroelectronics.
   5  */
   6
   7 #include <linux/clk.h>
   8 #include <linux/component.h>
   9 #include <linux/debugfs.h>
  10 #include <linux/module.h>
  11 #include <linux/of_gpio.h>
  12 #include <linux/platform_device.h>
  13
  14 #include <drm/drmP.h>
  15 #include <drm/drm_atomic_helper.h>
  16 #include <drm/drm_crtc_helper.h>
  17 #include <drm/drm_panel.h>
  18
  19 #include "sti_awg_utils.h"
  20 #include "sti_drv.h"
  21 #include "sti_mixer.h"
  22
  23 /* DVO registers */
  24 #define DVO_AWG_DIGSYNC_CTRL      0x0000
  25 #define DVO_DOF_CFG               0x0004
  26 #define DVO_LUT_PROG_LOW          0x0008
  27 #define DVO_LUT_PROG_MID          0x000C
  28 #define DVO_LUT_PROG_HIGH         0x0010
  29 #define DVO_DIGSYNC_INSTR_I       0x0100
  30
  31 #define DVO_AWG_CTRL_EN           BIT(0)
  32 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
  33
  34 #define DVO_DOF_EN_LOWBYTE        BIT(0)
  35 #define DVO_DOF_EN_MIDBYTE        BIT(1)
  36 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
  37 #define DVO_DOF_EN                BIT(6)
  38 #define DVO_DOF_MOD_COUNT_SHIFT   8
  39
  40 #define DVO_LUT_ZERO              0
  41 #define DVO_LUT_Y_G               1
  42 #define DVO_LUT_Y_G_DEL           2
  43 #define DVO_LUT_CB_B              3
  44 #define DVO_LUT_CB_B_DEL          4
  45 #define DVO_LUT_CR_R              5
  46 #define DVO_LUT_CR_R_DEL          6
  47 #define DVO_LUT_HOLD              7
  48
  49 struct dvo_config {
  50         u32 flags;
  51         u32 lowbyte;
  52         u32 midbyte;
  53         u32 highbyte;
  54         int (*awg_fwgen_fct)(
  55                         struct awg_code_generation_params *fw_gen_params,
  56                         struct awg_timing *timing);
  57 };
  58
  59 static struct dvo_config rgb_24bit_de_cfg = {
  60         .flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
  61         .lowbyte       = DVO_LUT_CR_R,
  62         .midbyte       = DVO_LUT_Y_G,
  63         .highbyte      = DVO_LUT_CB_B,
  64         .awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
  65 };
  66
  67 /**
  68  * STI digital video output structure
  69  *
  70  * @dev: driver device
  71  * @drm_dev: pointer to drm device
  72  * @mode: current display mode selected
  73  * @regs: dvo registers
  74  * @clk_pix: pixel clock for dvo
  75  * @clk: clock for dvo
  76  * @clk_main_parent: dvo parent clock if main path used
  77  * @clk_aux_parent: dvo parent clock if aux path used
  78  * @panel_node: panel node reference from device tree
  79  * @panel: reference to the panel connected to the dvo
  80  * @enabled: true if dvo is enabled else false
  81  * @encoder: drm_encoder it is bound
  82  */
  83 struct sti_dvo {
  84         struct device dev;
  85         struct drm_device *drm_dev;
  86         struct drm_display_mode mode;
  87         void __iomem *regs;
  88         struct clk *clk_pix;
  89         struct clk *clk;
  90         struct clk *clk_main_parent;
  91         struct clk *clk_aux_parent;
  92         struct device_node *panel_node;
  93         struct drm_panel *panel;
  94         struct dvo_config *config;
  95         bool enabled;
  96         struct drm_encoder *encoder;
  97         struct drm_bridge *bridge;
  98 };
  99
 100 struct sti_dvo_connector {
 101         struct drm_connector drm_connector;
 102         struct drm_encoder *encoder;
 103         struct sti_dvo *dvo;
 104 };
 105
 106 #define to_sti_dvo_connector(x) \
 107         container_of(x, struct sti_dvo_connector, drm_connector)
 108
 109 #define BLANKING_LEVEL 16
 110 static int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
 111 {
 112         struct drm_display_mode *mode = &dvo->mode;
 113         struct dvo_config *config = dvo->config;
 114         struct awg_code_generation_params fw_gen_params;
 115         struct awg_timing timing;
 116
 117         fw_gen_params.ram_code = ram_code;
 118         fw_gen_params.instruction_offset = 0;
 119
 120         timing.total_lines = mode->vtotal;
 121         timing.active_lines = mode->vdisplay;
 122         timing.blanking_lines = mode->vsync_start - mode->vdisplay;
 123         timing.trailing_lines = mode->vtotal - mode->vsync_start;
 124         timing.total_pixels = mode->htotal;
 125         timing.active_pixels = mode->hdisplay;
 126         timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
 127         timing.trailing_pixels = mode->htotal - mode->hsync_start;
 128         timing.blanking_level = BLANKING_LEVEL;
 129
 130         if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
 131                 DRM_ERROR("AWG firmware not properly generated\n");
 132                 return -EINVAL;
 133         }
 134
 135         *ram_size = fw_gen_params.instruction_offset;
 136
 137         return 0;
 138 }
 139
 140 /* Configure AWG, writing instructions
 141  *
 142  * @dvo: pointer to DVO structure
 143  * @awg_ram_code: pointer to AWG instructions table
 144  * @nb: nb of AWG instructions
 145  */
 146 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
 147 {
 148         int i;
 149
 150         DRM_DEBUG_DRIVER("\n");
 151
 152         for (i = 0; i < nb; i++)
 153                 writel(awg_ram_code[i],
 154                        dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 155         for (i = nb; i < AWG_MAX_INST; i++)
 156                 writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 157
 158         writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 159 }
 160
 161 #define DBGFS_DUMP(reg) seq_printf(s, "\n  %-25s 0x%08X", #reg, \
 162                                    readl(dvo->regs + reg))
 163
 164 static void dvo_dbg_awg_microcode(struct seq_file *s, void __iomem *reg)
 165 {
 166         unsigned int i;
 167
 168         seq_puts(s, "\n\n");
 169         seq_puts(s, "  DVO AWG microcode:");
 170         for (i = 0; i < AWG_MAX_INST; i++) {
 171                 if (i % 8 == 0)
 172                         seq_printf(s, "\n  %04X:", i);
 173                 seq_printf(s, " %04X", readl(reg + i * 4));
 174         }
 175 }
 176
 177 static int dvo_dbg_show(struct seq_file *s, void *data)
 178 {
 179         struct drm_info_node *node = s->private;
 180         struct sti_dvo *dvo = (struct sti_dvo *)node->info_ent->data;
 181
 182         seq_printf(s, "DVO: (vaddr = 0x%p)", dvo->regs);
 183         DBGFS_DUMP(DVO_AWG_DIGSYNC_CTRL);
 184         DBGFS_DUMP(DVO_DOF_CFG);
 185         DBGFS_DUMP(DVO_LUT_PROG_LOW);
 186         DBGFS_DUMP(DVO_LUT_PROG_MID);
 187         DBGFS_DUMP(DVO_LUT_PROG_HIGH);
 188         dvo_dbg_awg_microcode(s, dvo->regs + DVO_DIGSYNC_INSTR_I);
 189         seq_putc(s, '\n');
 190         return 0;
 191 }
 192
 193 static struct drm_info_list dvo_debugfs_files[] = {
 194         { "dvo", dvo_dbg_show, 0, NULL },
 195 };
 196
 197 static int dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
 198 {
 199         unsigned int i;
 200
 201         for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
 202                 dvo_debugfs_files[i].data = dvo;
 203
 204         return drm_debugfs_create_files(dvo_debugfs_files,
 205                                         ARRAY_SIZE(dvo_debugfs_files),
 206                                         minor->debugfs_root, minor);
 207 }
 208
 209 static void sti_dvo_disable(struct drm_bridge *bridge)
 210 {
 211         struct sti_dvo *dvo = bridge->driver_private;
 212
 213         if (!dvo->enabled)
 214                 return;
 215
 216         DRM_DEBUG_DRIVER("\n");
 217
 218         if (dvo->config->awg_fwgen_fct)
 219                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 220
 221         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 222
 223         if (dvo->panel)
 224                 dvo->panel->funcs->disable(dvo->panel);
 225
 226         /* Disable/unprepare dvo clock */
 227         clk_disable_unprepare(dvo->clk_pix);
 228         clk_disable_unprepare(dvo->clk);
 229
 230         dvo->enabled = false;
 231 }
 232
 233 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
 234 {
 235         struct sti_dvo *dvo = bridge->driver_private;
 236         struct dvo_config *config = dvo->config;
 237         u32 val;
 238
 239         DRM_DEBUG_DRIVER("\n");
 240
 241         if (dvo->enabled)
 242                 return;
 243
 244         /* Make sure DVO is disabled */
 245         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 246         writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 247
 248         if (config->awg_fwgen_fct) {
 249                 u8 nb_instr;
 250                 u32 awg_ram_code[AWG_MAX_INST];
 251                 /* Configure AWG */
 252                 if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
 253                         dvo_awg_configure(dvo, awg_ram_code, nb_instr);
 254                 else
 255                         return;
 256         }
 257
 258         /* Prepare/enable clocks */
 259         if (clk_prepare_enable(dvo->clk_pix))
 260                 DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
 261         if (clk_prepare_enable(dvo->clk))
 262                 DRM_ERROR("Failed to prepare/enable dvo clk\n");
 263
 264         if (dvo->panel)
 265                 dvo->panel->funcs->enable(dvo->panel);
 266
 267         /* Set LUT */
 268         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 269         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 270         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 271
 272         /* Digital output formatter config */
 273         val = (config->flags | DVO_DOF_EN);
 274         writel(val, dvo->regs + DVO_DOF_CFG);
 275
 276         dvo->enabled = true;
 277 }
 278
 279 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 280                              struct drm_display_mode *mode,
 281                              struct drm_display_mode *adjusted_mode)
 282 {
 283         struct sti_dvo *dvo = bridge->driver_private;
 284         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 285         int rate = mode->clock * 1000;
 286         struct clk *clkp;
 287         int ret;
 288
 289         DRM_DEBUG_DRIVER("\n");
 290
 291         memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
 292
 293         /* According to the path used (main or aux), the dvo clocks should
 294          * have a different parent clock. */
 295         if (mixer->id == STI_MIXER_MAIN)
 296                 clkp = dvo->clk_main_parent;
 297         else
 298                 clkp = dvo->clk_aux_parent;
 299
 300         if (clkp) {
 301                 clk_set_parent(dvo->clk_pix, clkp);
 302                 clk_set_parent(dvo->clk, clkp);
 303         }
 304
 305         /* DVO clocks = compositor clock */
 306         ret = clk_set_rate(dvo->clk_pix, rate);
 307         if (ret < 0) {
 308                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 309                 return;
 310         }
 311
 312         ret = clk_set_rate(dvo->clk, rate);
 313         if (ret < 0) {
 314                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 315                 return;
 316         }
 317
 318         /* For now, we only support 24bit data enable (DE) synchro format */
 319         dvo->config = &rgb_24bit_de_cfg;
 320 }
 321
 322 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 323 {
 324         /* do nothing */
 325 }
 326
 327 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 328         .pre_enable = sti_dvo_pre_enable,
 329         .enable = sti_dvo_bridge_nope,
 330         .disable = sti_dvo_disable,
 331         .post_disable = sti_dvo_bridge_nope,
 332         .mode_set = sti_dvo_set_mode,
 333 };
 334
 335 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 336 {
 337         struct sti_dvo_connector *dvo_connector
 338                 = to_sti_dvo_connector(connector);
 339         struct sti_dvo *dvo = dvo_connector->dvo;
 340
 341         if (dvo->panel)
 342                 return dvo->panel->funcs->get_modes(dvo->panel);
 343
 344         return 0;
 345 }
 346
 347 #define CLK_TOLERANCE_HZ 50
 348
 349 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
 350                                         struct drm_display_mode *mode)
 351 {
 352         int target = mode->clock * 1000;
 353         int target_min = target - CLK_TOLERANCE_HZ;
 354         int target_max = target + CLK_TOLERANCE_HZ;
 355         int result;
 356         struct sti_dvo_connector *dvo_connector
 357                 = to_sti_dvo_connector(connector);
 358         struct sti_dvo *dvo = dvo_connector->dvo;
 359
 360         result = clk_round_rate(dvo->clk_pix, target);
 361
 362         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 363                          target, result);
 364
 365         if ((result < target_min) || (result > target_max)) {
 366                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 367                 return MODE_BAD;
 368         }
 369
 370         return MODE_OK;
 371 }
 372
 373 static const
 374 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 375         .get_modes = sti_dvo_connector_get_modes,
 376         .mode_valid = sti_dvo_connector_mode_valid,
 377 };
 378
 379 static enum drm_connector_status
 380 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 381 {
 382         struct sti_dvo_connector *dvo_connector
 383                 = to_sti_dvo_connector(connector);
 384         struct sti_dvo *dvo = dvo_connector->dvo;
 385
 386         DRM_DEBUG_DRIVER("\n");
 387
 388         if (!dvo->panel) {
 389                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 390                 if (IS_ERR(dvo->panel))
 391                         dvo->panel = NULL;
 392                 else
 393                         drm_panel_attach(dvo->panel, connector);
 394         }
 395
 396         if (dvo->panel)
 397                 return connector_status_connected;
 398
 399         return connector_status_disconnected;
 400 }
 401
 402 static int sti_dvo_late_register(struct drm_connector *connector)
 403 {
 404         struct sti_dvo_connector *dvo_connector
 405                 = to_sti_dvo_connector(connector);
 406         struct sti_dvo *dvo = dvo_connector->dvo;
 407
 408         if (dvo_debugfs_init(dvo, dvo->drm_dev->primary)) {
 409                 DRM_ERROR("DVO debugfs setup failed\n");
 410                 return -EINVAL;
 411         }
 412
 413         return 0;
 414 }
 415
 416 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
 417         .fill_modes = drm_helper_probe_single_connector_modes,
 418         .detect = sti_dvo_connector_detect,
 419         .destroy = drm_connector_cleanup,
 420         .reset = drm_atomic_helper_connector_reset,
 421         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 422         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 423         .late_register = sti_dvo_late_register,
 424 };
 425
 426 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 427 {
 428         struct drm_encoder *encoder;
 429
 430         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 431                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 432                         return encoder;
 433         }
 434
 435         return NULL;
 436 }
 437
 438 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 439 {
 440         struct sti_dvo *dvo = dev_get_drvdata(dev);
 441         struct drm_device *drm_dev = data;
 442         struct drm_encoder *encoder;
 443         struct sti_dvo_connector *connector;
 444         struct drm_connector *drm_connector;
 445         struct drm_bridge *bridge;
 446         int err;
 447
 448         /* Set the drm device handle */
 449         dvo->drm_dev = drm_dev;
 450
 451         encoder = sti_dvo_find_encoder(drm_dev);
 452         if (!encoder)
 453                 return -ENOMEM;
 454
 455         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 456         if (!connector)
 457                 return -ENOMEM;
 458
 459         connector->dvo = dvo;
 460
 461         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 462         if (!bridge)
 463                 return -ENOMEM;
 464
 465         bridge->driver_private = dvo;
 466         bridge->funcs = &sti_dvo_bridge_funcs;
 467         bridge->of_node = dvo->dev.of_node;
 468         drm_bridge_add(bridge);
 469
 470         err = drm_bridge_attach(encoder, bridge, NULL);
 471         if (err) {
 472                 DRM_ERROR("Failed to attach bridge\n");
 473                 return err;
 474         }
 475
 476         dvo->bridge = bridge;
 477         connector->encoder = encoder;
 478         dvo->encoder = encoder;
 479
 480         drm_connector = (struct drm_connector *)connector;
 481
 482         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 483
 484         drm_connector_init(drm_dev, drm_connector,
 485                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 486         drm_connector_helper_add(drm_connector,
 487                                  &sti_dvo_connector_helper_funcs);
 488
 489         err = drm_connector_attach_encoder(drm_connector, encoder);
 490         if (err) {
 491                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 492                 goto err_sysfs;
 493         }
 494
 495         return 0;
 496
 497 err_sysfs:
 498         drm_bridge_remove(bridge);
 499         return -EINVAL;
 500 }
 501
 502 static void sti_dvo_unbind(struct device *dev,
 503                            struct device *master, void *data)
 504 {
 505         struct sti_dvo *dvo = dev_get_drvdata(dev);
 506
 507         drm_bridge_remove(dvo->bridge);
 508 }
 509
 510 static const struct component_ops sti_dvo_ops = {
 511         .bind = sti_dvo_bind,
 512         .unbind = sti_dvo_unbind,
 513 };
 514
 515 static int sti_dvo_probe(struct platform_device *pdev)
 516 {
 517         struct device *dev = &pdev->dev;
 518         struct sti_dvo *dvo;
 519         struct resource *res;
 520         struct device_node *np = dev->of_node;
 521
 522         DRM_INFO("%s\n", __func__);
 523
 524         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 525         if (!dvo) {
 526                 DRM_ERROR("Failed to allocate memory for DVO\n");
 527                 return -ENOMEM;
 528         }
 529
 530         dvo->dev = pdev->dev;
 531
 532         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 533         if (!res) {
 534                 DRM_ERROR("Invalid dvo resource\n");
 535                 return -ENOMEM;
 536         }
 537         dvo->regs = devm_ioremap_nocache(dev, res->start,
 538                         resource_size(res));
 539         if (!dvo->regs)
 540                 return -ENOMEM;
 541
 542         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 543         if (IS_ERR(dvo->clk_pix)) {
 544                 DRM_ERROR("Cannot get dvo_pix clock\n");
 545                 return PTR_ERR(dvo->clk_pix);
 546         }
 547
 548         dvo->clk = devm_clk_get(dev, "dvo");
 549         if (IS_ERR(dvo->clk)) {
 550                 DRM_ERROR("Cannot get dvo clock\n");
 551                 return PTR_ERR(dvo->clk);
 552         }
 553
 554         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 555         if (IS_ERR(dvo->clk_main_parent)) {
 556                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 557                 dvo->clk_main_parent = NULL;
 558         }
 559
 560         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 561         if (IS_ERR(dvo->clk_aux_parent)) {
 562                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 563                 dvo->clk_aux_parent = NULL;
 564         }
 565
 566         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 567         if (!dvo->panel_node)
 568                 DRM_ERROR("No panel associated to the dvo output\n");
 569         of_node_put(dvo->panel_node);
 570
 571         platform_set_drvdata(pdev, dvo);
 572
 573         return component_add(&pdev->dev, &sti_dvo_ops);
 574 }
 575
 576 static int sti_dvo_remove(struct platform_device *pdev)
 577 {
 578         component_del(&pdev->dev, &sti_dvo_ops);
 579         return 0;
 580 }
 581
 582 static const struct of_device_id dvo_of_match[] = {
 583         { .compatible = "st,stih407-dvo", },
 584         { /* end node */ }
 585 };
 586 MODULE_DEVICE_TABLE(of, dvo_of_match);
 587
 588 struct platform_driver sti_dvo_driver = {
 589         .driver = {
 590                 .name = "sti-dvo",
 591                 .owner = THIS_MODULE,
 592                 .of_match_table = dvo_of_match,
 593         },
 594         .probe = sti_dvo_probe,
 595         .remove = sti_dvo_remove,
 596 };
 597
 598 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 599 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 600 MODULE_LICENSE("GPL");