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