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_mixer.h"
  21
  22 /* DVO registers */
  23 #define DVO_AWG_DIGSYNC_CTRL      0x0000
  24 #define DVO_DOF_CFG               0x0004
  25 #define DVO_LUT_PROG_LOW          0x0008
  26 #define DVO_LUT_PROG_MID          0x000C
  27 #define DVO_LUT_PROG_HIGH         0x0010
  28 #define DVO_DIGSYNC_INSTR_I       0x0100
  29
  30 #define DVO_AWG_CTRL_EN           BIT(0)
  31 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
  32
  33 #define DVO_DOF_EN_LOWBYTE        BIT(0)
  34 #define DVO_DOF_EN_MIDBYTE        BIT(1)
  35 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
  36 #define DVO_DOF_EN                BIT(6)
  37 #define DVO_DOF_MOD_COUNT_SHIFT   8
  38
  39 #define DVO_LUT_ZERO              0
  40 #define DVO_LUT_Y_G               1
  41 #define DVO_LUT_Y_G_DEL           2
  42 #define DVO_LUT_CB_B              3
  43 #define DVO_LUT_CB_B_DEL          4
  44 #define DVO_LUT_CR_R              5
  45 #define DVO_LUT_CR_R_DEL          6
  46 #define DVO_LUT_HOLD              7
  47
  48 struct dvo_config {
  49         u32 flags;
  50         u32 lowbyte;
  51         u32 midbyte;
  52         u32 highbyte;
  53         int (*awg_fwgen_fct)(
  54                         struct awg_code_generation_params *fw_gen_params,
  55                         struct awg_timing *timing);
  56 };
  57
  58 static struct dvo_config rgb_24bit_de_cfg = {
  59         .flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
  60         .lowbyte       = DVO_LUT_CR_R,
  61         .midbyte       = DVO_LUT_Y_G,
  62         .highbyte      = DVO_LUT_CB_B,
  63         .awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
  64 };
  65
  66 /**
  67  * STI digital video output structure
  68  *
  69  * @dev: driver device
  70  * @drm_dev: pointer to drm device
  71  * @mode: current display mode selected
  72  * @regs: dvo registers
  73  * @clk_pix: pixel clock for dvo
  74  * @clk: clock for dvo
  75  * @clk_main_parent: dvo parent clock if main path used
  76  * @clk_aux_parent: dvo parent clock if aux path used
  77  * @panel_node: panel node reference from device tree
  78  * @panel: reference to the panel connected to the dvo
  79  * @enabled: true if dvo is enabled else false
  80  * @encoder: drm_encoder it is bound
  81  */
  82 struct sti_dvo {
  83         struct device dev;
  84         struct drm_device *drm_dev;
  85         struct drm_display_mode mode;
  86         void __iomem *regs;
  87         struct clk *clk_pix;
  88         struct clk *clk;
  89         struct clk *clk_main_parent;
  90         struct clk *clk_aux_parent;
  91         struct device_node *panel_node;
  92         struct drm_panel *panel;
  93         struct dvo_config *config;
  94         bool enabled;
  95         struct drm_encoder *encoder;
  96         struct drm_bridge *bridge;
  97 };
  98
  99 struct sti_dvo_connector {
 100         struct drm_connector drm_connector;
 101         struct drm_encoder *encoder;
 102         struct sti_dvo *dvo;
 103 };
 104
 105 #define to_sti_dvo_connector(x) \
 106         container_of(x, struct sti_dvo_connector, drm_connector)
 107
 108 #define BLANKING_LEVEL 16
 109 int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
 110 {
 111         struct drm_display_mode *mode = &dvo->mode;
 112         struct dvo_config *config = dvo->config;
 113         struct awg_code_generation_params fw_gen_params;
 114         struct awg_timing timing;
 115
 116         fw_gen_params.ram_code = ram_code;
 117         fw_gen_params.instruction_offset = 0;
 118
 119         timing.total_lines = mode->vtotal;
 120         timing.active_lines = mode->vdisplay;
 121         timing.blanking_lines = mode->vsync_start - mode->vdisplay;
 122         timing.trailing_lines = mode->vtotal - mode->vsync_start;
 123         timing.total_pixels = mode->htotal;
 124         timing.active_pixels = mode->hdisplay;
 125         timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
 126         timing.trailing_pixels = mode->htotal - mode->hsync_start;
 127         timing.blanking_level = BLANKING_LEVEL;
 128
 129         if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
 130                 DRM_ERROR("AWG firmware not properly generated\n");
 131                 return -EINVAL;
 132         }
 133
 134         *ram_size = fw_gen_params.instruction_offset;
 135
 136         return 0;
 137 }
 138
 139 /* Configure AWG, writing instructions
 140  *
 141  * @dvo: pointer to DVO structure
 142  * @awg_ram_code: pointer to AWG instructions table
 143  * @nb: nb of AWG instructions
 144  */
 145 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
 146 {
 147         int i;
 148
 149         DRM_DEBUG_DRIVER("\n");
 150
 151         for (i = 0; i < nb; i++)
 152                 writel(awg_ram_code[i],
 153                        dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 154         for (i = nb; i < AWG_MAX_INST; i++)
 155                 writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 156
 157         writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 158 }
 159
 160 #define DBGFS_DUMP(reg) seq_printf(s, "\n  %-25s 0x%08X", #reg, \
 161                                    readl(dvo->regs + reg))
 162
 163 static void dvo_dbg_awg_microcode(struct seq_file *s, void __iomem *reg)
 164 {
 165         unsigned int i;
 166
 167         seq_puts(s, "\n\n");
 168         seq_puts(s, "  DVO AWG microcode:");
 169         for (i = 0; i < AWG_MAX_INST; i++) {
 170                 if (i % 8 == 0)
 171                         seq_printf(s, "\n  %04X:", i);
 172                 seq_printf(s, " %04X", readl(reg + i * 4));
 173         }
 174 }
 175
 176 static int dvo_dbg_show(struct seq_file *s, void *data)
 177 {
 178         struct drm_info_node *node = s->private;
 179         struct sti_dvo *dvo = (struct sti_dvo *)node->info_ent->data;
 180
 181         seq_printf(s, "DVO: (vaddr = 0x%p)", dvo->regs);
 182         DBGFS_DUMP(DVO_AWG_DIGSYNC_CTRL);
 183         DBGFS_DUMP(DVO_DOF_CFG);
 184         DBGFS_DUMP(DVO_LUT_PROG_LOW);
 185         DBGFS_DUMP(DVO_LUT_PROG_MID);
 186         DBGFS_DUMP(DVO_LUT_PROG_HIGH);
 187         dvo_dbg_awg_microcode(s, dvo->regs + DVO_DIGSYNC_INSTR_I);
 188         seq_puts(s, "\n");
 189
 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 void dvo_debugfs_exit(struct sti_dvo *dvo, struct drm_minor *minor)
 198 {
 199         drm_debugfs_remove_files(dvo_debugfs_files,
 200                                  ARRAY_SIZE(dvo_debugfs_files),
 201                                  minor);
 202 }
 203
 204 static int dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
 205 {
 206         unsigned int i;
 207
 208         for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
 209                 dvo_debugfs_files[i].data = dvo;
 210
 211         return drm_debugfs_create_files(dvo_debugfs_files,
 212                                         ARRAY_SIZE(dvo_debugfs_files),
 213                                         minor->debugfs_root, minor);
 214 }
 215
 216 static void sti_dvo_disable(struct drm_bridge *bridge)
 217 {
 218         struct sti_dvo *dvo = bridge->driver_private;
 219
 220         if (!dvo->enabled)
 221                 return;
 222
 223         DRM_DEBUG_DRIVER("\n");
 224
 225         if (dvo->config->awg_fwgen_fct)
 226                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 227
 228         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 229
 230         if (dvo->panel)
 231                 dvo->panel->funcs->disable(dvo->panel);
 232
 233         /* Disable/unprepare dvo clock */
 234         clk_disable_unprepare(dvo->clk_pix);
 235         clk_disable_unprepare(dvo->clk);
 236
 237         dvo->enabled = false;
 238 }
 239
 240 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
 241 {
 242         struct sti_dvo *dvo = bridge->driver_private;
 243         struct dvo_config *config = dvo->config;
 244         u32 val;
 245
 246         DRM_DEBUG_DRIVER("\n");
 247
 248         if (dvo->enabled)
 249                 return;
 250
 251         /* Make sure DVO is disabled */
 252         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 253         writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 254
 255         if (config->awg_fwgen_fct) {
 256                 u8 nb_instr;
 257                 u32 awg_ram_code[AWG_MAX_INST];
 258                 /* Configure AWG */
 259                 if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
 260                         dvo_awg_configure(dvo, awg_ram_code, nb_instr);
 261                 else
 262                         return;
 263         }
 264
 265         /* Prepare/enable clocks */
 266         if (clk_prepare_enable(dvo->clk_pix))
 267                 DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
 268         if (clk_prepare_enable(dvo->clk))
 269                 DRM_ERROR("Failed to prepare/enable dvo clk\n");
 270
 271         if (dvo->panel)
 272                 dvo->panel->funcs->enable(dvo->panel);
 273
 274         /* Set LUT */
 275         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 276         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 277         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 278
 279         /* Digital output formatter config */
 280         val = (config->flags | DVO_DOF_EN);
 281         writel(val, dvo->regs + DVO_DOF_CFG);
 282
 283         dvo->enabled = true;
 284 }
 285
 286 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 287                              struct drm_display_mode *mode,
 288                              struct drm_display_mode *adjusted_mode)
 289 {
 290         struct sti_dvo *dvo = bridge->driver_private;
 291         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 292         int rate = mode->clock * 1000;
 293         struct clk *clkp;
 294         int ret;
 295
 296         DRM_DEBUG_DRIVER("\n");
 297
 298         memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
 299
 300         /* According to the path used (main or aux), the dvo clocks should
 301          * have a different parent clock. */
 302         if (mixer->id == STI_MIXER_MAIN)
 303                 clkp = dvo->clk_main_parent;
 304         else
 305                 clkp = dvo->clk_aux_parent;
 306
 307         if (clkp) {
 308                 clk_set_parent(dvo->clk_pix, clkp);
 309                 clk_set_parent(dvo->clk, clkp);
 310         }
 311
 312         /* DVO clocks = compositor clock */
 313         ret = clk_set_rate(dvo->clk_pix, rate);
 314         if (ret < 0) {
 315                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 316                 return;
 317         }
 318
 319         ret = clk_set_rate(dvo->clk, rate);
 320         if (ret < 0) {
 321                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 322                 return;
 323         }
 324
 325         /* For now, we only support 24bit data enable (DE) synchro format */
 326         dvo->config = &rgb_24bit_de_cfg;
 327 }
 328
 329 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 330 {
 331         /* do nothing */
 332 }
 333
 334 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 335         .pre_enable = sti_dvo_pre_enable,
 336         .enable = sti_dvo_bridge_nope,
 337         .disable = sti_dvo_disable,
 338         .post_disable = sti_dvo_bridge_nope,
 339         .mode_set = sti_dvo_set_mode,
 340 };
 341
 342 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 343 {
 344         struct sti_dvo_connector *dvo_connector
 345                 = to_sti_dvo_connector(connector);
 346         struct sti_dvo *dvo = dvo_connector->dvo;
 347
 348         if (dvo->panel)
 349                 return dvo->panel->funcs->get_modes(dvo->panel);
 350
 351         return 0;
 352 }
 353
 354 #define CLK_TOLERANCE_HZ 50
 355
 356 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
 357                                         struct drm_display_mode *mode)
 358 {
 359         int target = mode->clock * 1000;
 360         int target_min = target - CLK_TOLERANCE_HZ;
 361         int target_max = target + CLK_TOLERANCE_HZ;
 362         int result;
 363         struct sti_dvo_connector *dvo_connector
 364                 = to_sti_dvo_connector(connector);
 365         struct sti_dvo *dvo = dvo_connector->dvo;
 366
 367         result = clk_round_rate(dvo->clk_pix, target);
 368
 369         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 370                          target, result);
 371
 372         if ((result < target_min) || (result > target_max)) {
 373                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 374                 return MODE_BAD;
 375         }
 376
 377         return MODE_OK;
 378 }
 379
 380 static const
 381 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 382         .get_modes = sti_dvo_connector_get_modes,
 383         .mode_valid = sti_dvo_connector_mode_valid,
 384 };
 385
 386 static enum drm_connector_status
 387 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 388 {
 389         struct sti_dvo_connector *dvo_connector
 390                 = to_sti_dvo_connector(connector);
 391         struct sti_dvo *dvo = dvo_connector->dvo;
 392
 393         DRM_DEBUG_DRIVER("\n");
 394
 395         if (!dvo->panel) {
 396                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 397                 if (dvo->panel)
 398                         drm_panel_attach(dvo->panel, connector);
 399         }
 400
 401         if (dvo->panel)
 402                 return connector_status_connected;
 403
 404         return connector_status_disconnected;
 405 }
 406
 407 static int sti_dvo_late_register(struct drm_connector *connector)
 408 {
 409         struct sti_dvo_connector *dvo_connector
 410                 = to_sti_dvo_connector(connector);
 411         struct sti_dvo *dvo = dvo_connector->dvo;
 412
 413         if (dvo_debugfs_init(dvo, dvo->drm_dev->primary)) {
 414                 DRM_ERROR("DVO debugfs setup failed\n");
 415                 return -EINVAL;
 416         }
 417
 418         return 0;
 419 }
 420
 421 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
 422         .dpms = drm_atomic_helper_connector_dpms,
 423         .fill_modes = drm_helper_probe_single_connector_modes,
 424         .detect = sti_dvo_connector_detect,
 425         .destroy = drm_connector_cleanup,
 426         .reset = drm_atomic_helper_connector_reset,
 427         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 428         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 429         .late_register = sti_dvo_late_register,
 430 };
 431
 432 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 433 {
 434         struct drm_encoder *encoder;
 435
 436         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 437                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 438                         return encoder;
 439         }
 440
 441         return NULL;
 442 }
 443
 444 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 445 {
 446         struct sti_dvo *dvo = dev_get_drvdata(dev);
 447         struct drm_device *drm_dev = data;
 448         struct drm_encoder *encoder;
 449         struct sti_dvo_connector *connector;
 450         struct drm_connector *drm_connector;
 451         struct drm_bridge *bridge;
 452         int err;
 453
 454         /* Set the drm device handle */
 455         dvo->drm_dev = drm_dev;
 456
 457         encoder = sti_dvo_find_encoder(drm_dev);
 458         if (!encoder)
 459                 return -ENOMEM;
 460
 461         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 462         if (!connector)
 463                 return -ENOMEM;
 464
 465         connector->dvo = dvo;
 466
 467         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 468         if (!bridge)
 469                 return -ENOMEM;
 470
 471         bridge->driver_private = dvo;
 472         bridge->funcs = &sti_dvo_bridge_funcs;
 473         bridge->of_node = dvo->dev.of_node;
 474         err = drm_bridge_add(bridge);
 475         if (err) {
 476                 DRM_ERROR("Failed to add bridge\n");
 477                 return err;
 478         }
 479
 480         err = drm_bridge_attach(drm_dev, bridge);
 481         if (err) {
 482                 DRM_ERROR("Failed to attach bridge\n");
 483                 return err;
 484         }
 485
 486         dvo->bridge = bridge;
 487         encoder->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");