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/io.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/platform_device.h>
  14
  15 #include <drm/drm_atomic_helper.h>
  16 #include <drm/drm_bridge.h>
  17 #include <drm/drm_device.h>
  18 #include <drm/drm_panel.h>
  19 #include <drm/drm_print.h>
  20 #include <drm/drm_probe_helper.h>
  21
  22 #include "sti_awg_utils.h"
  23 #include "sti_drv.h"
  24 #include "sti_mixer.h"
  25
  26 /* DVO registers */
  27 #define DVO_AWG_DIGSYNC_CTRL      0x0000
  28 #define DVO_DOF_CFG               0x0004
  29 #define DVO_LUT_PROG_LOW          0x0008
  30 #define DVO_LUT_PROG_MID          0x000C
  31 #define DVO_LUT_PROG_HIGH         0x0010
  32 #define DVO_DIGSYNC_INSTR_I       0x0100
  33
  34 #define DVO_AWG_CTRL_EN           BIT(0)
  35 #define DVO_AWG_FRAME_BASED_SYNC  BIT(2)
  36
  37 #define DVO_DOF_EN_LOWBYTE        BIT(0)
  38 #define DVO_DOF_EN_MIDBYTE        BIT(1)
  39 #define DVO_DOF_EN_HIGHBYTE       BIT(2)
  40 #define DVO_DOF_EN                BIT(6)
  41 #define DVO_DOF_MOD_COUNT_SHIFT   8
  42
  43 #define DVO_LUT_ZERO              0
  44 #define DVO_LUT_Y_G               1
  45 #define DVO_LUT_Y_G_DEL           2
  46 #define DVO_LUT_CB_B              3
  47 #define DVO_LUT_CB_B_DEL          4
  48 #define DVO_LUT_CR_R              5
  49 #define DVO_LUT_CR_R_DEL          6
  50 #define DVO_LUT_HOLD              7
  51
  52 struct dvo_config {
  53         u32 flags;
  54         u32 lowbyte;
  55         u32 midbyte;
  56         u32 highbyte;
  57         int (*awg_fwgen_fct)(
  58                         struct awg_code_generation_params *fw_gen_params,
  59                         struct awg_timing *timing);
  60 };
  61
  62 static struct dvo_config rgb_24bit_de_cfg = {
  63         .flags         = (0L << DVO_DOF_MOD_COUNT_SHIFT),
  64         .lowbyte       = DVO_LUT_CR_R,
  65         .midbyte       = DVO_LUT_Y_G,
  66         .highbyte      = DVO_LUT_CB_B,
  67         .awg_fwgen_fct = sti_awg_generate_code_data_enable_mode,
  68 };
  69
  70 /*
  71  * STI digital video output structure
  72  *
  73  * @dev: driver device
  74  * @drm_dev: pointer to drm device
  75  * @mode: current display mode selected
  76  * @regs: dvo registers
  77  * @clk_pix: pixel clock for dvo
  78  * @clk: clock for dvo
  79  * @clk_main_parent: dvo parent clock if main path used
  80  * @clk_aux_parent: dvo parent clock if aux path used
  81  * @panel_node: panel node reference from device tree
  82  * @panel: reference to the panel connected to the dvo
  83  * @enabled: true if dvo is enabled else false
  84  * @encoder: drm_encoder it is bound
  85  */
  86 struct sti_dvo {
  87         struct device dev;
  88         struct drm_device *drm_dev;
  89         struct drm_display_mode mode;
  90         void __iomem *regs;
  91         struct clk *clk_pix;
  92         struct clk *clk;
  93         struct clk *clk_main_parent;
  94         struct clk *clk_aux_parent;
  95         struct device_node *panel_node;
  96         struct drm_panel *panel;
  97         struct dvo_config *config;
  98         bool enabled;
  99         struct drm_encoder *encoder;
 100         struct drm_bridge *bridge;
 101 };
 102
 103 struct sti_dvo_connector {
 104         struct drm_connector drm_connector;
 105         struct drm_encoder *encoder;
 106         struct sti_dvo *dvo;
 107 };
 108
 109 #define to_sti_dvo_connector(x) \
 110         container_of(x, struct sti_dvo_connector, drm_connector)
 111
 112 #define BLANKING_LEVEL 16
 113 static int dvo_awg_generate_code(struct sti_dvo *dvo, u8 *ram_size, u32 *ram_code)
 114 {
 115         struct drm_display_mode *mode = &dvo->mode;
 116         struct dvo_config *config = dvo->config;
 117         struct awg_code_generation_params fw_gen_params;
 118         struct awg_timing timing;
 119
 120         fw_gen_params.ram_code = ram_code;
 121         fw_gen_params.instruction_offset = 0;
 122
 123         timing.total_lines = mode->vtotal;
 124         timing.active_lines = mode->vdisplay;
 125         timing.blanking_lines = mode->vsync_start - mode->vdisplay;
 126         timing.trailing_lines = mode->vtotal - mode->vsync_start;
 127         timing.total_pixels = mode->htotal;
 128         timing.active_pixels = mode->hdisplay;
 129         timing.blanking_pixels = mode->hsync_start - mode->hdisplay;
 130         timing.trailing_pixels = mode->htotal - mode->hsync_start;
 131         timing.blanking_level = BLANKING_LEVEL;
 132
 133         if (config->awg_fwgen_fct(&fw_gen_params, &timing)) {
 134                 DRM_ERROR("AWG firmware not properly generated\n");
 135                 return -EINVAL;
 136         }
 137
 138         *ram_size = fw_gen_params.instruction_offset;
 139
 140         return 0;
 141 }
 142
 143 /* Configure AWG, writing instructions
 144  *
 145  * @dvo: pointer to DVO structure
 146  * @awg_ram_code: pointer to AWG instructions table
 147  * @nb: nb of AWG instructions
 148  */
 149 static void dvo_awg_configure(struct sti_dvo *dvo, u32 *awg_ram_code, int nb)
 150 {
 151         int i;
 152
 153         DRM_DEBUG_DRIVER("\n");
 154
 155         for (i = 0; i < nb; i++)
 156                 writel(awg_ram_code[i],
 157                        dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 158         for (i = nb; i < AWG_MAX_INST; i++)
 159                 writel(0, dvo->regs + DVO_DIGSYNC_INSTR_I + i * 4);
 160
 161         writel(DVO_AWG_CTRL_EN, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 162 }
 163
 164 #define DBGFS_DUMP(reg) seq_printf(s, "\n  %-25s 0x%08X", #reg, \
 165                                    readl(dvo->regs + reg))
 166
 167 static void dvo_dbg_awg_microcode(struct seq_file *s, void __iomem *reg)
 168 {
 169         unsigned int i;
 170
 171         seq_puts(s, "\n\n");
 172         seq_puts(s, "  DVO AWG microcode:");
 173         for (i = 0; i < AWG_MAX_INST; i++) {
 174                 if (i % 8 == 0)
 175                         seq_printf(s, "\n  %04X:", i);
 176                 seq_printf(s, " %04X", readl(reg + i * 4));
 177         }
 178 }
 179
 180 static int dvo_dbg_show(struct seq_file *s, void *data)
 181 {
 182         struct drm_info_node *node = s->private;
 183         struct sti_dvo *dvo = (struct sti_dvo *)node->info_ent->data;
 184
 185         seq_printf(s, "DVO: (vaddr = 0x%p)", dvo->regs);
 186         DBGFS_DUMP(DVO_AWG_DIGSYNC_CTRL);
 187         DBGFS_DUMP(DVO_DOF_CFG);
 188         DBGFS_DUMP(DVO_LUT_PROG_LOW);
 189         DBGFS_DUMP(DVO_LUT_PROG_MID);
 190         DBGFS_DUMP(DVO_LUT_PROG_HIGH);
 191         dvo_dbg_awg_microcode(s, dvo->regs + DVO_DIGSYNC_INSTR_I);
 192         seq_putc(s, '\n');
 193         return 0;
 194 }
 195
 196 static struct drm_info_list dvo_debugfs_files[] = {
 197         { "dvo", dvo_dbg_show, 0, NULL },
 198 };
 199
 200 static void dvo_debugfs_init(struct sti_dvo *dvo, struct drm_minor *minor)
 201 {
 202         unsigned int i;
 203
 204         for (i = 0; i < ARRAY_SIZE(dvo_debugfs_files); i++)
 205                 dvo_debugfs_files[i].data = dvo;
 206
 207         drm_debugfs_create_files(dvo_debugfs_files,
 208                                  ARRAY_SIZE(dvo_debugfs_files),
 209                                  minor->debugfs_root, minor);
 210 }
 211
 212 static void sti_dvo_disable(struct drm_bridge *bridge)
 213 {
 214         struct sti_dvo *dvo = bridge->driver_private;
 215
 216         if (!dvo->enabled)
 217                 return;
 218
 219         DRM_DEBUG_DRIVER("\n");
 220
 221         if (dvo->config->awg_fwgen_fct)
 222                 writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 223
 224         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 225
 226         drm_panel_disable(dvo->panel);
 227
 228         /* Disable/unprepare dvo clock */
 229         clk_disable_unprepare(dvo->clk_pix);
 230         clk_disable_unprepare(dvo->clk);
 231
 232         dvo->enabled = false;
 233 }
 234
 235 static void sti_dvo_pre_enable(struct drm_bridge *bridge)
 236 {
 237         struct sti_dvo *dvo = bridge->driver_private;
 238         struct dvo_config *config = dvo->config;
 239         u32 val;
 240
 241         DRM_DEBUG_DRIVER("\n");
 242
 243         if (dvo->enabled)
 244                 return;
 245
 246         /* Make sure DVO is disabled */
 247         writel(0x00000000, dvo->regs + DVO_DOF_CFG);
 248         writel(0x00000000, dvo->regs + DVO_AWG_DIGSYNC_CTRL);
 249
 250         if (config->awg_fwgen_fct) {
 251                 u8 nb_instr;
 252                 u32 awg_ram_code[AWG_MAX_INST];
 253                 /* Configure AWG */
 254                 if (!dvo_awg_generate_code(dvo, &nb_instr, awg_ram_code))
 255                         dvo_awg_configure(dvo, awg_ram_code, nb_instr);
 256                 else
 257                         return;
 258         }
 259
 260         /* Prepare/enable clocks */
 261         if (clk_prepare_enable(dvo->clk_pix))
 262                 DRM_ERROR("Failed to prepare/enable dvo_pix clk\n");
 263         if (clk_prepare_enable(dvo->clk))
 264                 DRM_ERROR("Failed to prepare/enable dvo clk\n");
 265
 266         drm_panel_enable(dvo->panel);
 267
 268         /* Set LUT */
 269         writel(config->lowbyte,  dvo->regs + DVO_LUT_PROG_LOW);
 270         writel(config->midbyte,  dvo->regs + DVO_LUT_PROG_MID);
 271         writel(config->highbyte, dvo->regs + DVO_LUT_PROG_HIGH);
 272
 273         /* Digital output formatter config */
 274         val = (config->flags | DVO_DOF_EN);
 275         writel(val, dvo->regs + DVO_DOF_CFG);
 276
 277         dvo->enabled = true;
 278 }
 279
 280 static void sti_dvo_set_mode(struct drm_bridge *bridge,
 281                              const struct drm_display_mode *mode,
 282                              const struct drm_display_mode *adjusted_mode)
 283 {
 284         struct sti_dvo *dvo = bridge->driver_private;
 285         struct sti_mixer *mixer = to_sti_mixer(dvo->encoder->crtc);
 286         int rate = mode->clock * 1000;
 287         struct clk *clkp;
 288         int ret;
 289
 290         DRM_DEBUG_DRIVER("\n");
 291
 292         drm_mode_copy(&dvo->mode, mode);
 293
 294         /* According to the path used (main or aux), the dvo clocks should
 295          * have a different parent clock. */
 296         if (mixer->id == STI_MIXER_MAIN)
 297                 clkp = dvo->clk_main_parent;
 298         else
 299                 clkp = dvo->clk_aux_parent;
 300
 301         if (clkp) {
 302                 clk_set_parent(dvo->clk_pix, clkp);
 303                 clk_set_parent(dvo->clk, clkp);
 304         }
 305
 306         /* DVO clocks = compositor clock */
 307         ret = clk_set_rate(dvo->clk_pix, rate);
 308         if (ret < 0) {
 309                 DRM_ERROR("Cannot set rate (%dHz) for dvo_pix clk\n", rate);
 310                 return;
 311         }
 312
 313         ret = clk_set_rate(dvo->clk, rate);
 314         if (ret < 0) {
 315                 DRM_ERROR("Cannot set rate (%dHz) for dvo clk\n", rate);
 316                 return;
 317         }
 318
 319         /* For now, we only support 24bit data enable (DE) synchro format */
 320         dvo->config = &rgb_24bit_de_cfg;
 321 }
 322
 323 static void sti_dvo_bridge_nope(struct drm_bridge *bridge)
 324 {
 325         /* do nothing */
 326 }
 327
 328 static const struct drm_bridge_funcs sti_dvo_bridge_funcs = {
 329         .pre_enable = sti_dvo_pre_enable,
 330         .enable = sti_dvo_bridge_nope,
 331         .disable = sti_dvo_disable,
 332         .post_disable = sti_dvo_bridge_nope,
 333         .mode_set = sti_dvo_set_mode,
 334 };
 335
 336 static int sti_dvo_connector_get_modes(struct drm_connector *connector)
 337 {
 338         struct sti_dvo_connector *dvo_connector
 339                 = to_sti_dvo_connector(connector);
 340         struct sti_dvo *dvo = dvo_connector->dvo;
 341
 342         if (dvo->panel)
 343                 return drm_panel_get_modes(dvo->panel, connector);
 344
 345         return 0;
 346 }
 347
 348 #define CLK_TOLERANCE_HZ 50
 349
 350 static enum drm_mode_status
 351 sti_dvo_connector_mode_valid(struct drm_connector *connector,
 352                              struct drm_display_mode *mode)
 353 {
 354         int target = mode->clock * 1000;
 355         int target_min = target - CLK_TOLERANCE_HZ;
 356         int target_max = target + CLK_TOLERANCE_HZ;
 357         int result;
 358         struct sti_dvo_connector *dvo_connector
 359                 = to_sti_dvo_connector(connector);
 360         struct sti_dvo *dvo = dvo_connector->dvo;
 361
 362         result = clk_round_rate(dvo->clk_pix, target);
 363
 364         DRM_DEBUG_DRIVER("target rate = %d => available rate = %d\n",
 365                          target, result);
 366
 367         if ((result < target_min) || (result > target_max)) {
 368                 DRM_DEBUG_DRIVER("dvo pixclk=%d not supported\n", target);
 369                 return MODE_BAD;
 370         }
 371
 372         return MODE_OK;
 373 }
 374
 375 static const
 376 struct drm_connector_helper_funcs sti_dvo_connector_helper_funcs = {
 377         .get_modes = sti_dvo_connector_get_modes,
 378         .mode_valid = sti_dvo_connector_mode_valid,
 379 };
 380
 381 static enum drm_connector_status
 382 sti_dvo_connector_detect(struct drm_connector *connector, bool force)
 383 {
 384         struct sti_dvo_connector *dvo_connector
 385                 = to_sti_dvo_connector(connector);
 386         struct sti_dvo *dvo = dvo_connector->dvo;
 387
 388         DRM_DEBUG_DRIVER("\n");
 389
 390         if (!dvo->panel) {
 391                 dvo->panel = of_drm_find_panel(dvo->panel_node);
 392                 if (IS_ERR(dvo->panel))
 393                         dvo->panel = NULL;
 394         }
 395
 396         if (dvo->panel)
 397                 return connector_status_connected;
 398
 399         return connector_status_disconnected;
 400 }
 401
 402 static int sti_dvo_late_register(struct drm_connector *connector)
 403 {
 404         struct sti_dvo_connector *dvo_connector
 405                 = to_sti_dvo_connector(connector);
 406         struct sti_dvo *dvo = dvo_connector->dvo;
 407
 408         dvo_debugfs_init(dvo, dvo->drm_dev->primary);
 409
 410         return 0;
 411 }
 412
 413 static const struct drm_connector_funcs sti_dvo_connector_funcs = {
 414         .fill_modes = drm_helper_probe_single_connector_modes,
 415         .detect = sti_dvo_connector_detect,
 416         .destroy = drm_connector_cleanup,
 417         .reset = drm_atomic_helper_connector_reset,
 418         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 419         .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 420         .late_register = sti_dvo_late_register,
 421 };
 422
 423 static struct drm_encoder *sti_dvo_find_encoder(struct drm_device *dev)
 424 {
 425         struct drm_encoder *encoder;
 426
 427         list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
 428                 if (encoder->encoder_type == DRM_MODE_ENCODER_LVDS)
 429                         return encoder;
 430         }
 431
 432         return NULL;
 433 }
 434
 435 static int sti_dvo_bind(struct device *dev, struct device *master, void *data)
 436 {
 437         struct sti_dvo *dvo = dev_get_drvdata(dev);
 438         struct drm_device *drm_dev = data;
 439         struct drm_encoder *encoder;
 440         struct sti_dvo_connector *connector;
 441         struct drm_connector *drm_connector;
 442         struct drm_bridge *bridge;
 443         int err;
 444
 445         /* Set the drm device handle */
 446         dvo->drm_dev = drm_dev;
 447
 448         encoder = sti_dvo_find_encoder(drm_dev);
 449         if (!encoder)
 450                 return -ENOMEM;
 451
 452         connector = devm_kzalloc(dev, sizeof(*connector), GFP_KERNEL);
 453         if (!connector)
 454                 return -ENOMEM;
 455
 456         connector->dvo = dvo;
 457
 458         bridge = devm_kzalloc(dev, sizeof(*bridge), GFP_KERNEL);
 459         if (!bridge)
 460                 return -ENOMEM;
 461
 462         bridge->driver_private = dvo;
 463         bridge->funcs = &sti_dvo_bridge_funcs;
 464         bridge->of_node = dvo->dev.of_node;
 465         drm_bridge_add(bridge);
 466
 467         err = drm_bridge_attach(encoder, bridge, NULL, 0);
 468         if (err)
 469                 return err;
 470
 471         dvo->bridge = bridge;
 472         connector->encoder = encoder;
 473         dvo->encoder = encoder;
 474
 475         drm_connector = (struct drm_connector *)connector;
 476
 477         drm_connector->polled = DRM_CONNECTOR_POLL_HPD;
 478
 479         drm_connector_init(drm_dev, drm_connector,
 480                            &sti_dvo_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 481         drm_connector_helper_add(drm_connector,
 482                                  &sti_dvo_connector_helper_funcs);
 483
 484         err = drm_connector_attach_encoder(drm_connector, encoder);
 485         if (err) {
 486                 DRM_ERROR("Failed to attach a connector to a encoder\n");
 487                 goto err_sysfs;
 488         }
 489
 490         return 0;
 491
 492 err_sysfs:
 493         drm_bridge_remove(bridge);
 494         return -EINVAL;
 495 }
 496
 497 static void sti_dvo_unbind(struct device *dev,
 498                            struct device *master, void *data)
 499 {
 500         struct sti_dvo *dvo = dev_get_drvdata(dev);
 501
 502         drm_bridge_remove(dvo->bridge);
 503 }
 504
 505 static const struct component_ops sti_dvo_ops = {
 506         .bind = sti_dvo_bind,
 507         .unbind = sti_dvo_unbind,
 508 };
 509
 510 static int sti_dvo_probe(struct platform_device *pdev)
 511 {
 512         struct device *dev = &pdev->dev;
 513         struct sti_dvo *dvo;
 514         struct resource *res;
 515         struct device_node *np = dev->of_node;
 516
 517         DRM_INFO("%s\n", __func__);
 518
 519         dvo = devm_kzalloc(dev, sizeof(*dvo), GFP_KERNEL);
 520         if (!dvo) {
 521                 DRM_ERROR("Failed to allocate memory for DVO\n");
 522                 return -ENOMEM;
 523         }
 524
 525         dvo->dev = pdev->dev;
 526
 527         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dvo-reg");
 528         if (!res) {
 529                 DRM_ERROR("Invalid dvo resource\n");
 530                 return -ENOMEM;
 531         }
 532         dvo->regs = devm_ioremap(dev, res->start,
 533                         resource_size(res));
 534         if (!dvo->regs)
 535                 return -ENOMEM;
 536
 537         dvo->clk_pix = devm_clk_get(dev, "dvo_pix");
 538         if (IS_ERR(dvo->clk_pix)) {
 539                 DRM_ERROR("Cannot get dvo_pix clock\n");
 540                 return PTR_ERR(dvo->clk_pix);
 541         }
 542
 543         dvo->clk = devm_clk_get(dev, "dvo");
 544         if (IS_ERR(dvo->clk)) {
 545                 DRM_ERROR("Cannot get dvo clock\n");
 546                 return PTR_ERR(dvo->clk);
 547         }
 548
 549         dvo->clk_main_parent = devm_clk_get(dev, "main_parent");
 550         if (IS_ERR(dvo->clk_main_parent)) {
 551                 DRM_DEBUG_DRIVER("Cannot get main_parent clock\n");
 552                 dvo->clk_main_parent = NULL;
 553         }
 554
 555         dvo->clk_aux_parent = devm_clk_get(dev, "aux_parent");
 556         if (IS_ERR(dvo->clk_aux_parent)) {
 557                 DRM_DEBUG_DRIVER("Cannot get aux_parent clock\n");
 558                 dvo->clk_aux_parent = NULL;
 559         }
 560
 561         dvo->panel_node = of_parse_phandle(np, "sti,panel", 0);
 562         if (!dvo->panel_node)
 563                 DRM_ERROR("No panel associated to the dvo output\n");
 564         of_node_put(dvo->panel_node);
 565
 566         platform_set_drvdata(pdev, dvo);
 567
 568         return component_add(&pdev->dev, &sti_dvo_ops);
 569 }
 570
 571 static void sti_dvo_remove(struct platform_device *pdev)
 572 {
 573         component_del(&pdev->dev, &sti_dvo_ops);
 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                 .of_match_table = dvo_of_match,
 586         },
 587         .probe = sti_dvo_probe,
 588         .remove = sti_dvo_remove,
 589 };
 590
 591 MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
 592 MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
 593 MODULE_LICENSE("GPL");