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