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/drm_atomic_helper.h>
  15 #include <drm/drm_device.h>
  16 #include <drm/drm_panel.h>
  17 #include <drm/drm_print.h>
  18 #include <drm/drm_probe_helper.h>
  19
  20 #include "sti_awg_utils.h"
  21 #include "sti_drv.h"
  22 #include "sti_mixer.h"
  23
  24 /* DVO registers */
  25 #define DVO_AWG_DIGSYNC_CTRL      0x0000
  26 #define DVO_DOF_CFG               0x0004
  27 #define DVO_LUT_PROG_LOW          0x0008
  28 #define DVO_LUT_PROG_MID          0x000C
  29 #define DVO_LUT_PROG_HIGH         0x0010
  30 #define DVO_DIGSYNC_INSTR_I       0x0100
  31
  32 #define DVO_AWG_CTRL_EN           BIT(0)
  33 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
  34
  35 #define DVO_DOF_EN_LOWBYTE        BIT(0)
  36 #define DVO_DOF_EN_MIDBYTE        BIT(1)
  37 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
  38 #define DVO_DOF_EN                BIT(6)
  39 #define DVO_DOF_MOD_COUNT_SHIFT   8
  40
  41 #define DVO_LUT_ZERO              0
  42 #define DVO_LUT_Y_G               1
  43 #define DVO_LUT_Y_G_DEL           2
  44 #define DVO_LUT_CB_B              3
  45 #define DVO_LUT_CB_B_DEL          4
  46 #define DVO_LUT_CR_R              5
  47 #define DVO_LUT_CR_R_DEL          6
  48 #define DVO_LUT_HOLD              7
  49
  50 struct dvo_config {
  51         u32 flags;
  52         u32 lowbyte;
  53         u32 midbyte;
  54         u32 highbyte;
  55         int (*awg_fwgen_fct)(
  56                         struct awg_code_generation_params *fw_gen_params,
  57                         struct awg_timing *timing);
  58 };
  59
  60 static struct dvo_config rgb_24bit_de_cfg = {
  61         .flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
  62         .lowbyte       = DVO_LUT_CR_R,
  63         .midbyte       = DVO_LUT_Y_G,
  64         .highbyte      = DVO_LUT_CB_B,
  65         .awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
  66 };
  67
  68 /**
  69  * STI digital video output structure
  70  *
  71  * @dev: driver device
  72  * @drm_dev: pointer to drm device
  73  * @mode: current display mode selected
  74  * @regs: dvo registers
  75  * @clk_pix: pixel clock for dvo
  76  * @clk: clock for dvo
  77  * @clk_main_parent: dvo parent clock if main path used
  78  * @clk_aux_parent: dvo parent clock if aux path used
  79  * @panel_node: panel node reference from device tree
  80  * @panel: reference to the panel connected to the dvo
  81  * @enabled: true if dvo is enabled else false
  82  * @encoder: drm_encoder it is bound
  83  */
  84 struct sti_dvo {
  85         struct device dev;
  86         struct drm_device *drm_dev;
  87         struct drm_display_mode mode;
  88         void __iomem *regs;
  89         struct clk *clk_pix;
  90         struct clk *clk;
  91         struct clk *clk_main_parent;
  92         struct clk *clk_aux_parent;
  93         struct device_node *panel_node;
  94         struct drm_panel *panel;
  95         struct dvo_config *config;
  96         bool enabled;
  97         struct drm_encoder *encoder;
  98         struct drm_bridge *bridge;
  99 };
 100
 101 struct sti_dvo_connector {
 102         struct drm_connector drm_connector;
 103         struct drm_encoder *encoder;
 104         struct sti_dvo *dvo;
 105 };
 106
 107 #define to_sti_dvo_connector(x) \
 108         container_of(x, struct sti_dvo_connector, drm_connector)
 109
 110 #define BLANKING_LEVEL 16
 111 static int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
 112 {
 113         struct drm_display_mode *mode = &dvo->mode;
 114         struct dvo_config *config = dvo->config;
 115         struct awg_code_generation_params fw_gen_params;
 116         struct awg_timing timing;
 117
 118         fw_gen_params.ram_code = ram_code;
 119         fw_gen_params.instruction_offset = 0;
 120
 121         timing.total_lines = mode->vtotal;
 122         timing.active_lines = mode->vdisplay;
 123         timing.blanking_lines = mode->vsync_start - mode->vdisplay;
 124         timing.trailing_lines = mode->vtotal - mode->vsync_start;
 125         timing.total_pixels = mode->htotal;
 126         timing.active_pixels = mode->hdisplay;
 127         timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
 128         timing.trailing_pixels = mode->htotal - mode->hsync_start;
 129         timing.blanking_level = BLANKING_LEVEL;
 130
 131         if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
 132                 DRM_ERROR("AWG firmware not properly generated\n");
 133                 return -EINVAL;
 134         }
 135
 136         *ram_size = fw_gen_params.instruction_offset;
 137
 138         return 0;
 139 }
 140
 141 /* Configure AWG, writing instructions
 142  *
 143  * @dvo: pointer to DVO structure
 144  * @awg_ram_code: pointer to AWG instructions table
 145  * @nb: nb of AWG instructions
 146  */
 147 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
 148 {
 149         int i;
 150
 151         DRM_DEBUG_DRIVER("\n");
 152
 153         for (i = 0; i < nb; i++)
 154                 writel(awg_ram_code[i],
 155                        dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 156         for (i = nb; i < AWG_MAX_INST; i++)
 157                 writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 158
 159         writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 160 }
 161
 162 #define DBGFS_DUMP(reg) seq_printf(s, "\n  %-25s 0x%08X", #reg, \
 163                                    readl(dvo->regs + reg))
 164
 165 static void dvo_dbg_awg_microcode(struct seq_file *s, void __iomem *reg)
 166 {
 167         unsigned int i;
 168
 169         seq_puts(s, "\n\n");
 170         seq_puts(s, "  DVO AWG microcode:");
 171         for (i = 0; i < AWG_MAX_INST; i++) {
 172                 if (i % 8 == 0)
 173                         seq_printf(s, "\n  %04X:", i);
 174                 seq_printf(s, " %04X", readl(reg + i * 4));
 175         }
 176 }
 177
 178 static int dvo_dbg_show(struct seq_file *s, void *data)
 179 {
 180         struct drm_info_node *node = s->private;
 181         struct sti_dvo *dvo = (struct sti_dvo *)node->info_ent->data;
 182
 183         seq_printf(s, "DVO: (vaddr = 0x%p)", dvo->regs);
 184         DBGFS_DUMP(DVO_AWG_DIGSYNC_CTRL);
 185         DBGFS_DUMP(DVO_DOF_CFG);
 186         DBGFS_DUMP(DVO_LUT_PROG_LOW);
 187         DBGFS_DUMP(DVO_LUT_PROG_MID);
 188         DBGFS_DUMP(DVO_LUT_PROG_HIGH);
 189         dvo_dbg_awg_microcode(s, dvo->regs + DVO_DIGSYNC_INSTR_I);
 190         seq_putc(s, '\n');
 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         drm_panel_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         drm_panel_enable(dvo->panel);
 265
 266         /* Set LUT */
 267         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 268         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 269         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 270
 271         /* Digital output formatter config */
 272         val = (config->flags | DVO_DOF_EN);
 273         writel(val, dvo->regs + DVO_DOF_CFG);
 274
 275         dvo->enabled = true;
 276 }
 277
 278 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 279                              const struct drm_display_mode *mode,
 280                              const struct drm_display_mode *adjusted_mode)
 281 {
 282         struct sti_dvo *dvo = bridge->driver_private;
 283         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 284         int rate = mode->clock * 1000;
 285         struct clk *clkp;
 286         int ret;
 287
 288         DRM_DEBUG_DRIVER("\n");
 289
 290         memcpy(&dvo->mode, mode, sizeof(struct drm_display_mode));
 291
 292         /* According to the path used (main or aux), the dvo clocks should
 293          * have a different parent clock. */
 294         if (mixer->id == STI_MIXER_MAIN)
 295                 clkp = dvo->clk_main_parent;
 296         else
 297                 clkp = dvo->clk_aux_parent;
 298
 299         if (clkp) {
 300                 clk_set_parent(dvo->clk_pix, clkp);
 301                 clk_set_parent(dvo->clk, clkp);
 302         }
 303
 304         /* DVO clocks = compositor clock */
 305         ret = clk_set_rate(dvo->clk_pix, rate);
 306         if (ret < 0) {
 307                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 308                 return;
 309         }
 310
 311         ret = clk_set_rate(dvo->clk, rate);
 312         if (ret < 0) {
 313                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 314                 return;
 315         }
 316
 317         /* For now, we only support 24bit data enable (DE) synchro format */
 318         dvo->config = &rgb_24bit_de_cfg;
 319 }
 320
 321 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 322 {
 323         /* do nothing */
 324 }
 325
 326 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 327         .pre_enable = sti_dvo_pre_enable,
 328         .enable = sti_dvo_bridge_nope,
 329         .disable = sti_dvo_disable,
 330         .post_disable = sti_dvo_bridge_nope,
 331         .mode_set = sti_dvo_set_mode,
 332 };
 333
 334 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 335 {
 336         struct sti_dvo_connector *dvo_connector
 337                 = to_sti_dvo_connector(connector);
 338         struct sti_dvo *dvo = dvo_connector->dvo;
 339
 340         if (dvo->panel)
 341                 return drm_panel_get_modes(dvo->panel);
 342
 343         return 0;
 344 }
 345
 346 #define CLK_TOLERANCE_HZ 50
 347
 348 static int sti_dvo_connector_mode_valid(struct drm_connector *connector,
 349                                         struct drm_display_mode *mode)
 350 {
 351         int target = mode->clock * 1000;
 352         int target_min = target - CLK_TOLERANCE_HZ;
 353         int target_max = target + CLK_TOLERANCE_HZ;
 354         int result;
 355         struct sti_dvo_connector *dvo_connector
 356                 = to_sti_dvo_connector(connector);
 357         struct sti_dvo *dvo = dvo_connector->dvo;
 358
 359         result = clk_round_rate(dvo->clk_pix, target);
 360
 361         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 362                          target, result);
 363
 364         if ((result < target_min) || (result > target_max)) {
 365                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 366                 return MODE_BAD;
 367         }
 368
 369         return MODE_OK;
 370 }
 371
 372 static const
 373 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 374         .get_modes = sti_dvo_connector_get_modes,
 375         .mode_valid = sti_dvo_connector_mode_valid,
 376 };
 377
 378 static enum drm_connector_status
 379 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 380 {
 381         struct sti_dvo_connector *dvo_connector
 382                 = to_sti_dvo_connector(connector);
 383         struct sti_dvo *dvo = dvo_connector->dvo;
 384
 385         DRM_DEBUG_DRIVER("\n");
 386
 387         if (!dvo->panel) {
 388                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 389                 if (IS_ERR(dvo->panel))
 390                         dvo->panel = NULL;
 391                 else
 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         .fill_modes = drm_helper_probe_single_connector_modes,
 417         .detect = sti_dvo_connector_detect,
 418         .destroy = drm_connector_cleanup,
 419         .reset = drm_atomic_helper_connector_reset,
 420         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 421         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 422         .late_register = sti_dvo_late_register,
 423 };
 424
 425 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 426 {
 427         struct drm_encoder *encoder;
 428
 429         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 430                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 431                         return encoder;
 432         }
 433
 434         return NULL;
 435 }
 436
 437 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 438 {
 439         struct sti_dvo *dvo = dev_get_drvdata(dev);
 440         struct drm_device *drm_dev = data;
 441         struct drm_encoder *encoder;
 442         struct sti_dvo_connector *connector;
 443         struct drm_connector *drm_connector;
 444         struct drm_bridge *bridge;
 445         int err;
 446
 447         /* Set the drm device handle */
 448         dvo->drm_dev = drm_dev;
 449
 450         encoder = sti_dvo_find_encoder(drm_dev);
 451         if (!encoder)
 452                 return -ENOMEM;
 453
 454         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 455         if (!connector)
 456                 return -ENOMEM;
 457
 458         connector->dvo = dvo;
 459
 460         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 461         if (!bridge)
 462                 return -ENOMEM;
 463
 464         bridge->driver_private = dvo;
 465         bridge->funcs = &sti_dvo_bridge_funcs;
 466         bridge->of_node = dvo->dev.of_node;
 467         drm_bridge_add(bridge);
 468
 469         err = drm_bridge_attach(encoder, bridge, NULL);
 470         if (err) {
 471                 DRM_ERROR("Failed to attach bridge\n");
 472                 return err;
 473         }
 474
 475         dvo->bridge = bridge;
 476         connector->encoder = encoder;
 477         dvo->encoder = encoder;
 478
 479         drm_connector = (struct drm_connector *)connector;
 480
 481         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 482
 483         drm_connector_init(drm_dev, drm_connector,
 484                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 485         drm_connector_helper_add(drm_connector,
 486                                  &sti_dvo_connector_helper_funcs);
 487
 488         err = drm_connector_attach_encoder(drm_connector, encoder);
 489         if (err) {
 490                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 491                 goto err_sysfs;
 492         }
 493
 494         return 0;
 495
 496 err_sysfs:
 497         drm_bridge_remove(bridge);
 498         return -EINVAL;
 499 }
 500
 501 static void sti_dvo_unbind(struct device *dev,
 502                            struct device *master, void *data)
 503 {
 504         struct sti_dvo *dvo = dev_get_drvdata(dev);
 505
 506         drm_bridge_remove(dvo->bridge);
 507 }
 508
 509 static const struct component_ops sti_dvo_ops = {
 510         .bind = sti_dvo_bind,
 511         .unbind = sti_dvo_unbind,
 512 };
 513
 514 static int sti_dvo_probe(struct platform_device *pdev)
 515 {
 516         struct device *dev = &pdev->dev;
 517         struct sti_dvo *dvo;
 518         struct resource *res;
 519         struct device_node *np = dev->of_node;
 520
 521         DRM_INFO("%s\n", __func__);
 522
 523         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 524         if (!dvo) {
 525                 DRM_ERROR("Failed to allocate memory for DVO\n");
 526                 return -ENOMEM;
 527         }
 528
 529         dvo->dev = pdev->dev;
 530
 531         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 532         if (!res) {
 533                 DRM_ERROR("Invalid dvo resource\n");
 534                 return -ENOMEM;
 535         }
 536         dvo->regs = devm_ioremap_nocache(dev, res->start,
 537                         resource_size(res));
 538         if (!dvo->regs)
 539                 return -ENOMEM;
 540
 541         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 542         if (IS_ERR(dvo->clk_pix)) {
 543                 DRM_ERROR("Cannot get dvo_pix clock\n");
 544                 return PTR_ERR(dvo->clk_pix);
 545         }
 546
 547         dvo->clk = devm_clk_get(dev, "dvo");
 548         if (IS_ERR(dvo->clk)) {
 549                 DRM_ERROR("Cannot get dvo clock\n");
 550                 return PTR_ERR(dvo->clk);
 551         }
 552
 553         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 554         if (IS_ERR(dvo->clk_main_parent)) {
 555                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 556                 dvo->clk_main_parent = NULL;
 557         }
 558
 559         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 560         if (IS_ERR(dvo->clk_aux_parent)) {
 561                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 562                 dvo->clk_aux_parent = NULL;
 563         }
 564
 565         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 566         if (!dvo->panel_node)
 567                 DRM_ERROR("No panel associated to the dvo output\n");
 568         of_node_put(dvo->panel_node);
 569
 570         platform_set_drvdata(pdev, dvo);
 571
 572         return component_add(&pdev->dev, &sti_dvo_ops);
 573 }
 574
 575 static int sti_dvo_remove(struct platform_device *pdev)
 576 {
 577         component_del(&pdev->dev, &sti_dvo_ops);
 578         return 0;
 579 }
 580
 581 static const struct of_device_id dvo_of_match[] = {
 582         { .compatible = "st,stih407-dvo", },
 583         { /* end node */ }
 584 };
 585 MODULE_DEVICE_TABLE(of, dvo_of_match);
 586
 587 struct platform_driver sti_dvo_driver = {
 588         .driver = {
 589                 .name = "sti-dvo",
 590                 .owner = THIS_MODULE,
 591                 .of_match_table = dvo_of_match,
 592         },
 593         .probe = sti_dvo_probe,
 594         .remove = sti_dvo_remove,
 595 };
 596
 597 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 598 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 599 MODULE_LICENSE("GPL");