drivers/gpu/drm/sti/sti_dvo.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) STMicroelectronics SA 2014
   4  * Author: Vincent Abriou <vincent.abriou@st.com> for STMicroelectronics.
   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_putc(s, '\n');
 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 int dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
 198 {
 199         unsigned int i;
 200
 201         for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
 202                 dvo_debugfs_files[i].data = dvo;
 203
 204         return drm_debugfs_create_files(dvo_debugfs_files,
 205                                         ARRAY_SIZE(dvo_debugfs_files),
 206                                         minor->debugfs_root, minor);
 207 }
 208
 209 static void sti_dvo_disable(struct drm_bridge *bridge)
 210 {
 211         struct sti_dvo *dvo = bridge->driver_private;
 212
 213         if (!dvo->enabled)
 214                 return;
 215
 216         DRM_DEBUG_DRIVER("\n");
 217
 218         if (dvo->config->awg_fwgen_fct)
 219                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 220
 221         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 222
 223         if (dvo->panel)
 224                 dvo->panel->funcs->disable(dvo->panel);
 225
 226         /* Disable/unprepare dvo clock */
 227         clk_disable_unprepare(dvo->clk_pix);
 228         clk_disable_unprepare(dvo->clk);
 229
 230         dvo->enabled = false;
 231 }
 232
 233 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
 234 {
 235         struct sti_dvo *dvo = bridge->driver_private;
 236         struct dvo_config *config = dvo->config;
 237         u32 val;
 238
 239         DRM_DEBUG_DRIVER("\n");
 240
 241         if (dvo->enabled)
 242                 return;
 243
 244         /* Make sure DVO is disabled */
 245         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 246         writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 247
 248         if (config->awg_fwgen_fct) {
 249                 u8 nb_instr;
 250                 u32 awg_ram_code[AWG_MAX_INST];
 251                 /* Configure AWG */
 252                 if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
 253                         dvo_awg_configure(dvo, awg_ram_code, nb_instr);
 254                 else
 255                         return;
 256         }
 257
 258         /* Prepare/enable clocks */
 259         if (clk_prepare_enable(dvo->clk_pix))
 260                 DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
 261         if (clk_prepare_enable(dvo->clk))
 262                 DRM_ERROR("Failed to prepare/enable dvo clk\n");
 263
 264         if (dvo->panel)
 265                 dvo->panel->funcs->enable(dvo->panel);
 266
 267         /* Set LUT */
 268         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 269         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 270         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 271
 272         /* Digital output formatter config */
 273         val = (config->flags | DVO_DOF_EN);
 274         writel(val, dvo->regs + DVO_DOF_CFG);
 275
 276         dvo->enabled = true;
 277 }
 278
 279 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 280                              struct drm_display_mode *mode,
 281                              struct drm_display_mode *adjusted_mode)
 282 {
 283         struct sti_dvo *dvo = bridge->driver_private;
 284         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 285         int rate = mode->clock * 1000;
 286         struct clk *clkp;
 287         int ret;
 288
 289         DRM_DEBUG_DRIVER("\n");
 290
 291         memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
 292
 293         /* According to the path used (main or aux), the dvo clocks should
 294          * have a different parent clock. */
 295         if (mixer->id == STI_MIXER_MAIN)
 296                 clkp = dvo->clk_main_parent;
 297         else
 298                 clkp = dvo->clk_aux_parent;
 299
 300         if (clkp) {
 301                 clk_set_parent(dvo->clk_pix, clkp);
 302                 clk_set_parent(dvo->clk, clkp);
 303         }
 304
 305         /* DVO clocks = compositor clock */
 306         ret = clk_set_rate(dvo->clk_pix, rate);
 307         if (ret < 0) {
 308                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 309                 return;
 310         }
 311
 312         ret = clk_set_rate(dvo->clk, rate);
 313         if (ret < 0) {
 314                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 315                 return;
 316         }
 317
 318         /* For now, we only support 24bit data enable (DE) synchro format */
 319         dvo->config = &rgb_24bit_de_cfg;
 320 }
 321
 322 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 323 {
 324         /* do nothing */
 325 }
 326
 327 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 328         .pre_enable = sti_dvo_pre_enable,
 329         .enable = sti_dvo_bridge_nope,
 330         .disable = sti_dvo_disable,
 331         .post_disable = sti_dvo_bridge_nope,
 332         .mode_set = sti_dvo_set_mode,
 333 };
 334
 335 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 336 {
 337         struct sti_dvo_connector *dvo_connector
 338                 = to_sti_dvo_connector(connector);
 339         struct sti_dvo *dvo = dvo_connector->dvo;
 340
 341         if (dvo->panel)
 342                 return dvo->panel->funcs->get_modes(dvo->panel);
 343
 344         return 0;
 345 }
 346
 347 #define CLK_TOLERANCE_HZ 50
 348
 349 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
 350                                         struct drm_display_mode *mode)
 351 {
 352         int target = mode->clock * 1000;
 353         int target_min = target - CLK_TOLERANCE_HZ;
 354         int target_max = target + CLK_TOLERANCE_HZ;
 355         int result;
 356         struct sti_dvo_connector *dvo_connector
 357                 = to_sti_dvo_connector(connector);
 358         struct sti_dvo *dvo = dvo_connector->dvo;
 359
 360         result = clk_round_rate(dvo->clk_pix, target);
 361
 362         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 363                          target, result);
 364
 365         if ((result < target_min) || (result > target_max)) {
 366                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 367                 return MODE_BAD;
 368         }
 369
 370         return MODE_OK;
 371 }
 372
 373 static const
 374 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 375         .get_modes = sti_dvo_connector_get_modes,
 376         .mode_valid = sti_dvo_connector_mode_valid,
 377 };
 378
 379 static enum drm_connector_status
 380 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 381 {
 382         struct sti_dvo_connector *dvo_connector
 383                 = to_sti_dvo_connector(connector);
 384         struct sti_dvo *dvo = dvo_connector->dvo;
 385
 386         DRM_DEBUG_DRIVER("\n");
 387
 388         if (!dvo->panel) {
 389                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 390                 if (dvo->panel)
 391                         drm_panel_attach(dvo->panel, connector);
 392         }
 393
 394         if (dvo->panel)
 395                 return connector_status_connected;
 396
 397         return connector_status_disconnected;
 398 }
 399
 400 static int sti_dvo_late_register(struct drm_connector *connector)
 401 {
 402         struct sti_dvo_connector *dvo_connector
 403                 = to_sti_dvo_connector(connector);
 404         struct sti_dvo *dvo = dvo_connector->dvo;
 405
 406         if (dvo_debugfs_init(dvo, dvo->drm_dev->primary)) {
 407                 DRM_ERROR("DVO debugfs setup failed\n");
 408                 return -EINVAL;
 409         }
 410
 411         return 0;
 412 }
 413
 414 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
 415         .fill_modes = drm_helper_probe_single_connector_modes,
 416         .detect = sti_dvo_connector_detect,
 417         .destroy = drm_connector_cleanup,
 418         .reset = drm_atomic_helper_connector_reset,
 419         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 420         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 421         .late_register = sti_dvo_late_register,
 422 };
 423
 424 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 425 {
 426         struct drm_encoder *encoder;
 427
 428         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 429                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 430                         return encoder;
 431         }
 432
 433         return NULL;
 434 }
 435
 436 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 437 {
 438         struct sti_dvo *dvo = dev_get_drvdata(dev);
 439         struct drm_device *drm_dev = data;
 440         struct drm_encoder *encoder;
 441         struct sti_dvo_connector *connector;
 442         struct drm_connector *drm_connector;
 443         struct drm_bridge *bridge;
 444         int err;
 445
 446         /* Set the drm device handle */
 447         dvo->drm_dev = drm_dev;
 448
 449         encoder = sti_dvo_find_encoder(drm_dev);
 450         if (!encoder)
 451                 return -ENOMEM;
 452
 453         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 454         if (!connector)
 455                 return -ENOMEM;
 456
 457         connector->dvo = dvo;
 458
 459         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 460         if (!bridge)
 461                 return -ENOMEM;
 462
 463         bridge->driver_private = dvo;
 464         bridge->funcs = &sti_dvo_bridge_funcs;
 465         bridge->of_node = dvo->dev.of_node;
 466         drm_bridge_add(bridge);
 467
 468         err = drm_bridge_attach(encoder, bridge, NULL);
 469         if (err) {
 470                 DRM_ERROR("Failed to attach bridge\n");
 471                 return err;
 472         }
 473
 474         dvo->bridge = bridge;
 475         connector->encoder = encoder;
 476         dvo->encoder = encoder;
 477
 478         drm_connector = (struct drm_connector *)connector;
 479
 480         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 481
 482         drm_connector_init(drm_dev, drm_connector,
 483                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 484         drm_connector_helper_add(drm_connector,
 485                                  &sti_dvo_connector_helper_funcs);
 486
 487         err = drm_mode_connector_attach_encoder(drm_connector, encoder);
 488         if (err) {
 489                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 490                 goto err_sysfs;
 491         }
 492
 493         return 0;
 494
 495 err_sysfs:
 496         drm_bridge_remove(bridge);
 497         return -EINVAL;
 498 }
 499
 500 static void sti_dvo_unbind(struct device *dev,
 501                            struct device *master, void *data)
 502 {
 503         struct sti_dvo *dvo = dev_get_drvdata(dev);
 504
 505         drm_bridge_remove(dvo->bridge);
 506 }
 507
 508 static const struct component_ops sti_dvo_ops = {
 509         .bind = sti_dvo_bind,
 510         .unbind = sti_dvo_unbind,
 511 };
 512
 513 static int sti_dvo_probe(struct platform_device *pdev)
 514 {
 515         struct device *dev = &pdev->dev;
 516         struct sti_dvo *dvo;
 517         struct resource *res;
 518         struct device_node *np = dev->of_node;
 519
 520         DRM_INFO("%s\n", __func__);
 521
 522         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 523         if (!dvo) {
 524                 DRM_ERROR("Failed to allocate memory for DVO\n");
 525                 return -ENOMEM;
 526         }
 527
 528         dvo->dev = pdev->dev;
 529
 530         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 531         if (!res) {
 532                 DRM_ERROR("Invalid dvo resource\n");
 533                 return -ENOMEM;
 534         }
 535         dvo->regs = devm_ioremap_nocache(dev, res->start,
 536                         resource_size(res));
 537         if (!dvo->regs)
 538                 return -ENOMEM;
 539
 540         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 541         if (IS_ERR(dvo->clk_pix)) {
 542                 DRM_ERROR("Cannot get dvo_pix clock\n");
 543                 return PTR_ERR(dvo->clk_pix);
 544         }
 545
 546         dvo->clk = devm_clk_get(dev, "dvo");
 547         if (IS_ERR(dvo->clk)) {
 548                 DRM_ERROR("Cannot get dvo clock\n");
 549                 return PTR_ERR(dvo->clk);
 550         }
 551
 552         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 553         if (IS_ERR(dvo->clk_main_parent)) {
 554                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 555                 dvo->clk_main_parent = NULL;
 556         }
 557
 558         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 559         if (IS_ERR(dvo->clk_aux_parent)) {
 560                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 561                 dvo->clk_aux_parent = NULL;
 562         }
 563
 564         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 565         if (!dvo->panel_node)
 566                 DRM_ERROR("No panel associated to the dvo output\n");
 567         of_node_put(dvo->panel_node);
 568
 569         platform_set_drvdata(pdev, dvo);
 570
 571         return component_add(&pdev->dev, &sti_dvo_ops);
 572 }
 573
 574 static int sti_dvo_remove(struct platform_device *pdev)
 575 {
 576         component_del(&pdev->dev, &sti_dvo_ops);
 577         return 0;
 578 }
 579
 580 static const struct of_device_id dvo_of_match[] = {
 581         { .compatible = "st,stih407-dvo", },
 582         { /* end node */ }
 583 };
 584 MODULE_DEVICE_TABLE(of, dvo_of_match);
 585
 586 struct platform_driver sti_dvo_driver = {
 587         .driver = {
 588                 .name = "sti-dvo",
 589                 .owner = THIS_MODULE,
 590                 .of_match_table = dvo_of_match,
 591         },
 592         .probe = sti_dvo_probe,
 593         .remove = sti_dvo_remove,
 594 };
 595
 596 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 597 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 598 MODULE_LICENSE("GPL");