drivers/gpu/drm/sti/sti_dvo.c

   1 /*
   2  * Copyright (C) STMicroelectronics SA 2014
   3  * Author: Vincent Abriou <vincent.abriou@st.com> for STMicroelectronics.
   4  * License terms:  GNU General Public License (GPL), version 2
   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_puts(s, "\n");
 190
 191         return 0;
 192 }
 193
 194 static struct drm_info_list dvo_debugfs_files[] = {
 195         { "dvo", dvo_dbg_show, 0, NULL },
 196 };
 197
 198 static void dvo_debugfs_exit(struct sti_dvo *dvo, struct drm_minor *minor)
 199 {
 200         drm_debugfs_remove_files(dvo_debugfs_files,
 201                                  ARRAY_SIZE(dvo_debugfs_files),
 202                                  minor);
 203 }
 204
 205 static int dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
 206 {
 207         unsigned int i;
 208
 209         for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
 210                 dvo_debugfs_files[i].data = dvo;
 211
 212         return drm_debugfs_create_files(dvo_debugfs_files,
 213                                         ARRAY_SIZE(dvo_debugfs_files),
 214                                         minor->debugfs_root, minor);
 215 }
 216
 217 static void sti_dvo_disable(struct drm_bridge *bridge)
 218 {
 219         struct sti_dvo *dvo = bridge->driver_private;
 220
 221         if (!dvo->enabled)
 222                 return;
 223
 224         DRM_DEBUG_DRIVER("\n");
 225
 226         if (dvo->config->awg_fwgen_fct)
 227                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 228
 229         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 230
 231         if (dvo->panel)
 232                 dvo->panel->funcs->disable(dvo->panel);
 233
 234         /* Disable/unprepare dvo clock */
 235         clk_disable_unprepare(dvo->clk_pix);
 236         clk_disable_unprepare(dvo->clk);
 237
 238         dvo->enabled = false;
 239 }
 240
 241 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
 242 {
 243         struct sti_dvo *dvo = bridge->driver_private;
 244         struct dvo_config *config = dvo->config;
 245         u32 val;
 246
 247         DRM_DEBUG_DRIVER("\n");
 248
 249         if (dvo->enabled)
 250                 return;
 251
 252         /* Make sure DVO is disabled */
 253         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 254         writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 255
 256         if (config->awg_fwgen_fct) {
 257                 u8 nb_instr;
 258                 u32 awg_ram_code[AWG_MAX_INST];
 259                 /* Configure AWG */
 260                 if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
 261                         dvo_awg_configure(dvo, awg_ram_code, nb_instr);
 262                 else
 263                         return;
 264         }
 265
 266         /* Prepare/enable clocks */
 267         if (clk_prepare_enable(dvo->clk_pix))
 268                 DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
 269         if (clk_prepare_enable(dvo->clk))
 270                 DRM_ERROR("Failed to prepare/enable dvo clk\n");
 271
 272         if (dvo->panel)
 273                 dvo->panel->funcs->enable(dvo->panel);
 274
 275         /* Set LUT */
 276         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 277         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 278         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 279
 280         /* Digital output formatter config */
 281         val = (config->flags | DVO_DOF_EN);
 282         writel(val, dvo->regs + DVO_DOF_CFG);
 283
 284         dvo->enabled = true;
 285 }
 286
 287 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 288                              struct drm_display_mode *mode,
 289                              struct drm_display_mode *adjusted_mode)
 290 {
 291         struct sti_dvo *dvo = bridge->driver_private;
 292         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 293         int rate = mode->clock * 1000;
 294         struct clk *clkp;
 295         int ret;
 296
 297         DRM_DEBUG_DRIVER("\n");
 298
 299         memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
 300
 301         /* According to the path used (main or aux), the dvo clocks should
 302          * have a different parent clock. */
 303         if (mixer->id == STI_MIXER_MAIN)
 304                 clkp = dvo->clk_main_parent;
 305         else
 306                 clkp = dvo->clk_aux_parent;
 307
 308         if (clkp) {
 309                 clk_set_parent(dvo->clk_pix, clkp);
 310                 clk_set_parent(dvo->clk, clkp);
 311         }
 312
 313         /* DVO clocks = compositor clock */
 314         ret = clk_set_rate(dvo->clk_pix, rate);
 315         if (ret < 0) {
 316                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 317                 return;
 318         }
 319
 320         ret = clk_set_rate(dvo->clk, rate);
 321         if (ret < 0) {
 322                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 323                 return;
 324         }
 325
 326         /* For now, we only support 24bit data enable (DE) synchro format */
 327         dvo->config = &rgb_24bit_de_cfg;
 328 }
 329
 330 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 331 {
 332         /* do nothing */
 333 }
 334
 335 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 336         .pre_enable = sti_dvo_pre_enable,
 337         .enable = sti_dvo_bridge_nope,
 338         .disable = sti_dvo_disable,
 339         .post_disable = sti_dvo_bridge_nope,
 340         .mode_set = sti_dvo_set_mode,
 341 };
 342
 343 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 344 {
 345         struct sti_dvo_connector *dvo_connector
 346                 = to_sti_dvo_connector(connector);
 347         struct sti_dvo *dvo = dvo_connector->dvo;
 348
 349         if (dvo->panel)
 350                 return dvo->panel->funcs->get_modes(dvo->panel);
 351
 352         return 0;
 353 }
 354
 355 #define CLK_TOLERANCE_HZ 50
 356
 357 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
 358                                         struct drm_display_mode *mode)
 359 {
 360         int target = mode->clock * 1000;
 361         int target_min = target - CLK_TOLERANCE_HZ;
 362         int target_max = target + CLK_TOLERANCE_HZ;
 363         int result;
 364         struct sti_dvo_connector *dvo_connector
 365                 = to_sti_dvo_connector(connector);
 366         struct sti_dvo *dvo = dvo_connector->dvo;
 367
 368         result = clk_round_rate(dvo->clk_pix, target);
 369
 370         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 371                          target, result);
 372
 373         if ((result < target_min) || (result > target_max)) {
 374                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 375                 return MODE_BAD;
 376         }
 377
 378         return MODE_OK;
 379 }
 380
 381 static const
 382 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 383         .get_modes = sti_dvo_connector_get_modes,
 384         .mode_valid = sti_dvo_connector_mode_valid,
 385 };
 386
 387 static enum drm_connector_status
 388 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 389 {
 390         struct sti_dvo_connector *dvo_connector
 391                 = to_sti_dvo_connector(connector);
 392         struct sti_dvo *dvo = dvo_connector->dvo;
 393
 394         DRM_DEBUG_DRIVER("\n");
 395
 396         if (!dvo->panel) {
 397                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 398                 if (dvo->panel)
 399                         drm_panel_attach(dvo->panel, connector);
 400         }
 401
 402         if (dvo->panel)
 403                 return connector_status_connected;
 404
 405         return connector_status_disconnected;
 406 }
 407
 408 static int sti_dvo_late_register(struct drm_connector *connector)
 409 {
 410         struct sti_dvo_connector *dvo_connector
 411                 = to_sti_dvo_connector(connector);
 412         struct sti_dvo *dvo = dvo_connector->dvo;
 413
 414         if (dvo_debugfs_init(dvo, dvo->drm_dev->primary)) {
 415                 DRM_ERROR("DVO debugfs setup failed\n");
 416                 return -EINVAL;
 417         }
 418
 419         return 0;
 420 }
 421
 422 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
 423         .dpms = drm_atomic_helper_connector_dpms,
 424         .fill_modes = drm_helper_probe_single_connector_modes,
 425         .detect = sti_dvo_connector_detect,
 426         .destroy = drm_connector_cleanup,
 427         .reset = drm_atomic_helper_connector_reset,
 428         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 429         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 430         .late_register = sti_dvo_late_register,
 431 };
 432
 433 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 434 {
 435         struct drm_encoder *encoder;
 436
 437         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 438                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 439                         return encoder;
 440         }
 441
 442         return NULL;
 443 }
 444
 445 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 446 {
 447         struct sti_dvo *dvo = dev_get_drvdata(dev);
 448         struct drm_device *drm_dev = data;
 449         struct drm_encoder *encoder;
 450         struct sti_dvo_connector *connector;
 451         struct drm_connector *drm_connector;
 452         struct drm_bridge *bridge;
 453         int err;
 454
 455         /* Set the drm device handle */
 456         dvo->drm_dev = drm_dev;
 457
 458         encoder = sti_dvo_find_encoder(drm_dev);
 459         if (!encoder)
 460                 return -ENOMEM;
 461
 462         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 463         if (!connector)
 464                 return -ENOMEM;
 465
 466         connector->dvo = dvo;
 467
 468         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 469         if (!bridge)
 470                 return -ENOMEM;
 471
 472         bridge->driver_private = dvo;
 473         bridge->funcs = &sti_dvo_bridge_funcs;
 474         bridge->of_node = dvo->dev.of_node;
 475         err = drm_bridge_add(bridge);
 476         if (err) {
 477                 DRM_ERROR("Failed to add bridge\n");
 478                 return err;
 479         }
 480
 481         err = drm_bridge_attach(encoder, bridge, NULL);
 482         if (err) {
 483                 DRM_ERROR("Failed to attach bridge\n");
 484                 return err;
 485         }
 486
 487         dvo->bridge = bridge;
 488         connector->encoder = encoder;
 489         dvo->encoder = encoder;
 490
 491         drm_connector = (struct drm_connector *)connector;
 492
 493         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 494
 495         drm_connector_init(drm_dev, drm_connector,
 496                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 497         drm_connector_helper_add(drm_connector,
 498                                  &sti_dvo_connector_helper_funcs);
 499
 500         err = drm_mode_connector_attach_encoder(drm_connector, encoder);
 501         if (err) {
 502                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 503                 goto err_sysfs;
 504         }
 505
 506         return 0;
 507
 508 err_sysfs:
 509         drm_bridge_remove(bridge);
 510         return -EINVAL;
 511 }
 512
 513 static void sti_dvo_unbind(struct device *dev,
 514                            struct device *master, void *data)
 515 {
 516         struct sti_dvo *dvo = dev_get_drvdata(dev);
 517         struct drm_device *drm_dev = data;
 518
 519         dvo_debugfs_exit(dvo, drm_dev->primary);
 520
 521         drm_bridge_remove(dvo->bridge);
 522 }
 523
 524 static const struct component_ops sti_dvo_ops = {
 525         .bind = sti_dvo_bind,
 526         .unbind = sti_dvo_unbind,
 527 };
 528
 529 static int sti_dvo_probe(struct platform_device *pdev)
 530 {
 531         struct device *dev = &pdev->dev;
 532         struct sti_dvo *dvo;
 533         struct resource *res;
 534         struct device_node *np = dev->of_node;
 535
 536         DRM_INFO("%s\n", __func__);
 537
 538         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 539         if (!dvo) {
 540                 DRM_ERROR("Failed to allocate memory for DVO\n");
 541                 return -ENOMEM;
 542         }
 543
 544         dvo->dev = pdev->dev;
 545
 546         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 547         if (!res) {
 548                 DRM_ERROR("Invalid dvo resource\n");
 549                 return -ENOMEM;
 550         }
 551         dvo->regs = devm_ioremap_nocache(dev, res->start,
 552                         resource_size(res));
 553         if (!dvo->regs)
 554                 return -ENOMEM;
 555
 556         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 557         if (IS_ERR(dvo->clk_pix)) {
 558                 DRM_ERROR("Cannot get dvo_pix clock\n");
 559                 return PTR_ERR(dvo->clk_pix);
 560         }
 561
 562         dvo->clk = devm_clk_get(dev, "dvo");
 563         if (IS_ERR(dvo->clk)) {
 564                 DRM_ERROR("Cannot get dvo clock\n");
 565                 return PTR_ERR(dvo->clk);
 566         }
 567
 568         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 569         if (IS_ERR(dvo->clk_main_parent)) {
 570                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 571                 dvo->clk_main_parent = NULL;
 572         }
 573
 574         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 575         if (IS_ERR(dvo->clk_aux_parent)) {
 576                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 577                 dvo->clk_aux_parent = NULL;
 578         }
 579
 580         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 581         if (!dvo->panel_node)
 582                 DRM_ERROR("No panel associated to the dvo output\n");
 583         of_node_put(dvo->panel_node);
 584
 585         platform_set_drvdata(pdev, dvo);
 586
 587         return component_add(&pdev->dev, &sti_dvo_ops);
 588 }
 589
 590 static int sti_dvo_remove(struct platform_device *pdev)
 591 {
 592         component_del(&pdev->dev, &sti_dvo_ops);
 593         return 0;
 594 }
 595
 596 static struct of_device_id dvo_of_match[] = {
 597         { .compatible = "st,stih407-dvo", },
 598         { /* end node */ }
 599 };
 600 MODULE_DEVICE_TABLE(of, dvo_of_match);
 601
 602 struct platform_driver sti_dvo_driver = {
 603         .driver = {
 604                 .name = "sti-dvo",
 605                 .owner = THIS_MODULE,
 606                 .of_match_table = dvo_of_match,
 607         },
 608         .probe = sti_dvo_probe,
 609         .remove = sti_dvo_remove,
 610 };
 611
 612 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 613 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 614 MODULE_LICENSE("GPL");