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_bridge.h>
  16 #include <drm/drm_device.h>
  17 #include <drm/drm_panel.h>
  18 #include <drm/drm_print.h>
  19 #include <drm/drm_probe_helper.h>
  20
  21 #include "sti_awg_utils.h"
  22 #include "sti_drv.h"
  23 #include "sti_mixer.h"
  24
  25 /* DVO registers */
  26 #define DVO_AWG_DIGSYNC_CTRL      0x0000
  27 #define DVO_DOF_CFG               0x0004
  28 #define DVO_LUT_PROG_LOW          0x0008
  29 #define DVO_LUT_PROG_MID          0x000C
  30 #define DVO_LUT_PROG_HIGH         0x0010
  31 #define DVO_DIGSYNC_INSTR_I       0x0100
  32
  33 #define DVO_AWG_CTRL_EN           BIT(0)
  34 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
  35
  36 #define DVO_DOF_EN_LOWBYTE        BIT(0)
  37 #define DVO_DOF_EN_MIDBYTE        BIT(1)
  38 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
  39 #define DVO_DOF_EN                BIT(6)
  40 #define DVO_DOF_MOD_COUNT_SHIFT   8
  41
  42 #define DVO_LUT_ZERO              0
  43 #define DVO_LUT_Y_G               1
  44 #define DVO_LUT_Y_G_DEL           2
  45 #define DVO_LUT_CB_B              3
  46 #define DVO_LUT_CB_B_DEL          4
  47 #define DVO_LUT_CR_R              5
  48 #define DVO_LUT_CR_R_DEL          6
  49 #define DVO_LUT_HOLD              7
  50
  51 struct dvo_config {
  52         u32 flags;
  53         u32 lowbyte;
  54         u32 midbyte;
  55         u32 highbyte;
  56         int (*awg_fwgen_fct)(
  57                         struct awg_code_generation_params *fw_gen_params,
  58                         struct awg_timing *timing);
  59 };
  60
  61 static struct dvo_config rgb_24bit_de_cfg = {
  62         .flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
  63         .lowbyte       = DVO_LUT_CR_R,
  64         .midbyte       = DVO_LUT_Y_G,
  65         .highbyte      = DVO_LUT_CB_B,
  66         .awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
  67 };
  68
  69 /*
  70  * STI digital video output structure
  71  *
  72  * @dev: driver device
  73  * @drm_dev: pointer to drm device
  74  * @mode: current display mode selected
  75  * @regs: dvo registers
  76  * @clk_pix: pixel clock for dvo
  77  * @clk: clock for dvo
  78  * @clk_main_parent: dvo parent clock if main path used
  79  * @clk_aux_parent: dvo parent clock if aux path used
  80  * @panel_node: panel node reference from device tree
  81  * @panel: reference to the panel connected to the dvo
  82  * @enabled: true if dvo is enabled else false
  83  * @encoder: drm_encoder it is bound
  84  */
  85 struct sti_dvo {
  86         struct device dev;
  87         struct drm_device *drm_dev;
  88         struct drm_display_mode mode;
  89         void __iomem *regs;
  90         struct clk *clk_pix;
  91         struct clk *clk;
  92         struct clk *clk_main_parent;
  93         struct clk *clk_aux_parent;
  94         struct device_node *panel_node;
  95         struct drm_panel *panel;
  96         struct dvo_config *config;
  97         bool enabled;
  98         struct drm_encoder *encoder;
  99         struct drm_bridge *bridge;
 100 };
 101
 102 struct sti_dvo_connector {
 103         struct drm_connector drm_connector;
 104         struct drm_encoder *encoder;
 105         struct sti_dvo *dvo;
 106 };
 107
 108 #define to_sti_dvo_connector(x) \
 109         container_of(x, struct sti_dvo_connector, drm_connector)
 110
 111 #define BLANKING_LEVEL 16
 112 static int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
 113 {
 114         struct drm_display_mode *mode = &dvo->mode;
 115         struct dvo_config *config = dvo->config;
 116         struct awg_code_generation_params fw_gen_params;
 117         struct awg_timing timing;
 118
 119         fw_gen_params.ram_code = ram_code;
 120         fw_gen_params.instruction_offset = 0;
 121
 122         timing.total_lines = mode->vtotal;
 123         timing.active_lines = mode->vdisplay;
 124         timing.blanking_lines = mode->vsync_start - mode->vdisplay;
 125         timing.trailing_lines = mode->vtotal - mode->vsync_start;
 126         timing.total_pixels = mode->htotal;
 127         timing.active_pixels = mode->hdisplay;
 128         timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
 129         timing.trailing_pixels = mode->htotal - mode->hsync_start;
 130         timing.blanking_level = BLANKING_LEVEL;
 131
 132         if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
 133                 DRM_ERROR("AWG firmware not properly generated\n");
 134                 return -EINVAL;
 135         }
 136
 137         *ram_size = fw_gen_params.instruction_offset;
 138
 139         return 0;
 140 }
 141
 142 /* Configure AWG, writing instructions
 143  *
 144  * @dvo: pointer to DVO structure
 145  * @awg_ram_code: pointer to AWG instructions table
 146  * @nb: nb of AWG instructions
 147  */
 148 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
 149 {
 150         int i;
 151
 152         DRM_DEBUG_DRIVER("\n");
 153
 154         for (i = 0; i < nb; i++)
 155                 writel(awg_ram_code[i],
 156                        dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 157         for (i = nb; i < AWG_MAX_INST; i++)
 158                 writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 159
 160         writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 161 }
 162
 163 #define DBGFS_DUMP(reg) seq_printf(s, "\n  %-25s 0x%08X", #reg, \
 164                                    readl(dvo->regs + reg))
 165
 166 static void dvo_dbg_awg_microcode(struct seq_file *s, void __iomem *reg)
 167 {
 168         unsigned int i;
 169
 170         seq_puts(s, "\n\n");
 171         seq_puts(s, "  DVO AWG microcode:");
 172         for (i = 0; i < AWG_MAX_INST; i++) {
 173                 if (i % 8 == 0)
 174                         seq_printf(s, "\n  %04X:", i);
 175                 seq_printf(s, " %04X", readl(reg + i * 4));
 176         }
 177 }
 178
 179 static int dvo_dbg_show(struct seq_file *s, void *data)
 180 {
 181         struct drm_info_node *node = s->private;
 182         struct sti_dvo *dvo = (struct sti_dvo *)node->info_ent->data;
 183
 184         seq_printf(s, "DVO: (vaddr = 0x%p)", dvo->regs);
 185         DBGFS_DUMP(DVO_AWG_DIGSYNC_CTRL);
 186         DBGFS_DUMP(DVO_DOF_CFG);
 187         DBGFS_DUMP(DVO_LUT_PROG_LOW);
 188         DBGFS_DUMP(DVO_LUT_PROG_MID);
 189         DBGFS_DUMP(DVO_LUT_PROG_HIGH);
 190         dvo_dbg_awg_microcode(s, dvo->regs + DVO_DIGSYNC_INSTR_I);
 191         seq_putc(s, '\n');
 192         return 0;
 193 }
 194
 195 static struct drm_info_list dvo_debugfs_files[] = {
 196         { "dvo", dvo_dbg_show, 0, NULL },
 197 };
 198
 199 static void dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
 200 {
 201         unsigned int i;
 202
 203         for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
 204                 dvo_debugfs_files[i].data = dvo;
 205
 206         drm_debugfs_create_files(dvo_debugfs_files,
 207                                  ARRAY_SIZE(dvo_debugfs_files),
 208                                  minor->debugfs_root, minor);
 209 }
 210
 211 static void sti_dvo_disable(struct drm_bridge *bridge)
 212 {
 213         struct sti_dvo *dvo = bridge->driver_private;
 214
 215         if (!dvo->enabled)
 216                 return;
 217
 218         DRM_DEBUG_DRIVER("\n");
 219
 220         if (dvo->config->awg_fwgen_fct)
 221                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 222
 223         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 224
 225         drm_panel_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         drm_panel_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                              const struct drm_display_mode *mode,
 281                              const 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         drm_mode_copy(&dvo->mode, 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 drm_panel_get_modes(dvo->panel, connector);
 343
 344         return 0;
 345 }
 346
 347 #define CLK_TOLERANCE_HZ 50
 348
 349 static enum drm_mode_status
 350 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 (IS_ERR(dvo->panel))
 392                         dvo->panel = NULL;
 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         dvo_debugfs_init(dvo, dvo->drm_dev->primary);
 408
 409         return 0;
 410 }
 411
 412 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
 413         .fill_modes = drm_helper_probe_single_connector_modes,
 414         .detect = sti_dvo_connector_detect,
 415         .destroy = drm_connector_cleanup,
 416         .reset = drm_atomic_helper_connector_reset,
 417         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 418         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 419         .late_register = sti_dvo_late_register,
 420 };
 421
 422 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 423 {
 424         struct drm_encoder *encoder;
 425
 426         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 427                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 428                         return encoder;
 429         }
 430
 431         return NULL;
 432 }
 433
 434 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 435 {
 436         struct sti_dvo *dvo = dev_get_drvdata(dev);
 437         struct drm_device *drm_dev = data;
 438         struct drm_encoder *encoder;
 439         struct sti_dvo_connector *connector;
 440         struct drm_connector *drm_connector;
 441         struct drm_bridge *bridge;
 442         int err;
 443
 444         /* Set the drm device handle */
 445         dvo->drm_dev = drm_dev;
 446
 447         encoder = sti_dvo_find_encoder(drm_dev);
 448         if (!encoder)
 449                 return -ENOMEM;
 450
 451         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 452         if (!connector)
 453                 return -ENOMEM;
 454
 455         connector->dvo = dvo;
 456
 457         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 458         if (!bridge)
 459                 return -ENOMEM;
 460
 461         bridge->driver_private = dvo;
 462         bridge->funcs = &sti_dvo_bridge_funcs;
 463         bridge->of_node = dvo->dev.of_node;
 464         drm_bridge_add(bridge);
 465
 466         err = drm_bridge_attach(encoder, bridge, NULL, 0);
 467         if (err)
 468                 return err;
 469
 470         dvo->bridge = bridge;
 471         connector->encoder = encoder;
 472         dvo->encoder = encoder;
 473
 474         drm_connector = (struct drm_connector *)connector;
 475
 476         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 477
 478         drm_connector_init(drm_dev, drm_connector,
 479                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 480         drm_connector_helper_add(drm_connector,
 481                                  &sti_dvo_connector_helper_funcs);
 482
 483         err = drm_connector_attach_encoder(drm_connector, encoder);
 484         if (err) {
 485                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 486                 goto err_sysfs;
 487         }
 488
 489         return 0;
 490
 491 err_sysfs:
 492         drm_bridge_remove(bridge);
 493         return -EINVAL;
 494 }
 495
 496 static void sti_dvo_unbind(struct device *dev,
 497                            struct device *master, void *data)
 498 {
 499         struct sti_dvo *dvo = dev_get_drvdata(dev);
 500
 501         drm_bridge_remove(dvo->bridge);
 502 }
 503
 504 static const struct component_ops sti_dvo_ops = {
 505         .bind = sti_dvo_bind,
 506         .unbind = sti_dvo_unbind,
 507 };
 508
 509 static int sti_dvo_probe(struct platform_device *pdev)
 510 {
 511         struct device *dev = &pdev->dev;
 512         struct sti_dvo *dvo;
 513         struct resource *res;
 514         struct device_node *np = dev->of_node;
 515
 516         DRM_INFO("%s\n", __func__);
 517
 518         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 519         if (!dvo) {
 520                 DRM_ERROR("Failed to allocate memory for DVO\n");
 521                 return -ENOMEM;
 522         }
 523
 524         dvo->dev = pdev->dev;
 525
 526         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 527         if (!res) {
 528                 DRM_ERROR("Invalid dvo resource\n");
 529                 return -ENOMEM;
 530         }
 531         dvo->regs = devm_ioremap(dev, res->start,
 532                         resource_size(res));
 533         if (!dvo->regs)
 534                 return -ENOMEM;
 535
 536         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 537         if (IS_ERR(dvo->clk_pix)) {
 538                 DRM_ERROR("Cannot get dvo_pix clock\n");
 539                 return PTR_ERR(dvo->clk_pix);
 540         }
 541
 542         dvo->clk = devm_clk_get(dev, "dvo");
 543         if (IS_ERR(dvo->clk)) {
 544                 DRM_ERROR("Cannot get dvo clock\n");
 545                 return PTR_ERR(dvo->clk);
 546         }
 547
 548         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 549         if (IS_ERR(dvo->clk_main_parent)) {
 550                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 551                 dvo->clk_main_parent = NULL;
 552         }
 553
 554         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 555         if (IS_ERR(dvo->clk_aux_parent)) {
 556                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 557                 dvo->clk_aux_parent = NULL;
 558         }
 559
 560         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 561         if (!dvo->panel_node)
 562                 DRM_ERROR("No panel associated to the dvo output\n");
 563         of_node_put(dvo->panel_node);
 564
 565         platform_set_drvdata(pdev, dvo);
 566
 567         return component_add(&pdev->dev, &sti_dvo_ops);
 568 }
 569
 570 static int sti_dvo_remove(struct platform_device *pdev)
 571 {
 572         component_del(&pdev->dev, &sti_dvo_ops);
 573         return 0;
 574 }
 575
 576 static const struct of_device_id dvo_of_match[] = {
 577         { .compatible = "st,stih407-dvo", },
 578         { /* end node */ }
 579 };
 580 MODULE_DEVICE_TABLE(of, dvo_of_match);
 581
 582 struct platform_driver sti_dvo_driver = {
 583         .driver = {
 584                 .name = "sti-dvo",
 585                 .owner = THIS_MODULE,
 586                 .of_match_table = dvo_of_match,
 587         },
 588         .probe = sti_dvo_probe,
 589         .remove = sti_dvo_remove,
 590 };
 591
 592 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 593 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 594 MODULE_LICENSE("GPL");