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