drivers/video/tegra.c

   1 /*
   2  * Copyright (c) 2011 The Chromium OS Authors.
   3  * SPDX-License-Identifier:     GPL-2.0+
   4  */
   5
   6 #include <common.h>
   7 #include <dm.h>
   8 #include <fdtdec.h>
   9 #include <pwm.h>
  10 #include <video.h>
  11 #include <asm/system.h>
  12 #include <asm/gpio.h>
  13 #include <asm/io.h>
  14
  15 #include <asm/arch/clock.h>
  16 #include <asm/arch/funcmux.h>
  17 #include <asm/arch/pinmux.h>
  18 #include <asm/arch/pwm.h>
  19 #include <asm/arch/display.h>
  20 #include <asm/arch-tegra/timer.h>
  21
  22 DECLARE_GLOBAL_DATA_PTR;
  23
  24 /* These are the stages we go throuh in enabling the LCD */
  25 enum stage_t {
  26         STAGE_START,
  27         STAGE_PANEL_VDD,
  28         STAGE_LVDS,
  29         STAGE_BACKLIGHT_VDD,
  30         STAGE_PWM,
  31         STAGE_BACKLIGHT_EN,
  32         STAGE_DONE,
  33 };
  34
  35 #define FDT_LCD_TIMINGS 4
  36
  37 enum {
  38         FDT_LCD_TIMING_REF_TO_SYNC,
  39         FDT_LCD_TIMING_SYNC_WIDTH,
  40         FDT_LCD_TIMING_BACK_PORCH,
  41         FDT_LCD_TIMING_FRONT_PORCH,
  42
  43         FDT_LCD_TIMING_COUNT,
  44 };
  45
  46 enum lcd_cache_t {
  47         FDT_LCD_CACHE_OFF               = 0,
  48         FDT_LCD_CACHE_WRITE_THROUGH     = 1 << 0,
  49         FDT_LCD_CACHE_WRITE_BACK        = 1 << 1,
  50         FDT_LCD_CACHE_FLUSH             = 1 << 2,
  51         FDT_LCD_CACHE_WRITE_BACK_FLUSH  = FDT_LCD_CACHE_WRITE_BACK |
  52                                                 FDT_LCD_CACHE_FLUSH,
  53 };
  54
  55 /* Information about the display controller */
  56 struct tegra_lcd_priv {
  57         enum stage_t stage;     /* Current stage we are at */
  58         unsigned long timer_next; /* Time we can move onto next stage */
  59         int width;                      /* width in pixels */
  60         int height;                     /* height in pixels */
  61
  62         /*
  63          * log2 of number of bpp, in general, unless it bpp is 24 in which
  64          * case this field holds 24 also! This is a U-Boot thing.
  65          */
  66         int log2_bpp;
  67         struct disp_ctlr *disp;         /* Display controller to use */
  68         fdt_addr_t frame_buffer;        /* Address of frame buffer */
  69         unsigned pixel_clock;           /* Pixel clock in Hz */
  70         uint horiz_timing[FDT_LCD_TIMING_COUNT];        /* Horizontal timing */
  71         uint vert_timing[FDT_LCD_TIMING_COUNT];         /* Vertical timing */
  72         struct udevice *pwm;
  73         int pwm_channel;                /* PWM channel to use for backlight */
  74         enum lcd_cache_t cache_type;
  75
  76         struct gpio_desc backlight_en;  /* GPIO for backlight enable */
  77         struct gpio_desc lvds_shutdown; /* GPIO for lvds shutdown */
  78         struct gpio_desc backlight_vdd; /* GPIO for backlight vdd */
  79         struct gpio_desc panel_vdd;     /* GPIO for panel vdd */
  80         /*
  81          * Panel required timings
  82          * Timing 1: delay between panel_vdd-rise and data-rise
  83          * Timing 2: delay between data-rise and backlight_vdd-rise
  84          * Timing 3: delay between backlight_vdd and pwm-rise
  85          * Timing 4: delay between pwm-rise and backlight_en-rise
  86          */
  87         uint panel_timings[FDT_LCD_TIMINGS];
  88 };
  89
  90 enum {
  91         /* Maximum LCD size we support */
  92         LCD_MAX_WIDTH           = 1366,
  93         LCD_MAX_HEIGHT          = 768,
  94         LCD_MAX_LOG2_BPP        = VIDEO_BPP16,
  95 };
  96
  97 static void update_window(struct dc_ctlr *dc, struct disp_ctl_win *win)
  98 {
  99         unsigned h_dda, v_dda;
 100         unsigned long val;
 101
 102         val = readl(&dc->cmd.disp_win_header);
 103         val |= WINDOW_A_SELECT;
 104         writel(val, &dc->cmd.disp_win_header);
 105
 106         writel(win->fmt, &dc->win.color_depth);
 107
 108         clrsetbits_le32(&dc->win.byte_swap, BYTE_SWAP_MASK,
 109                         BYTE_SWAP_NOSWAP << BYTE_SWAP_SHIFT);
 110
 111         val = win->out_x << H_POSITION_SHIFT;
 112         val |= win->out_y << V_POSITION_SHIFT;
 113         writel(val, &dc->win.pos);
 114
 115         val = win->out_w << H_SIZE_SHIFT;
 116         val |= win->out_h << V_SIZE_SHIFT;
 117         writel(val, &dc->win.size);
 118
 119         val = (win->w * win->bpp / 8) << H_PRESCALED_SIZE_SHIFT;
 120         val |= win->h << V_PRESCALED_SIZE_SHIFT;
 121         writel(val, &dc->win.prescaled_size);
 122
 123         writel(0, &dc->win.h_initial_dda);
 124         writel(0, &dc->win.v_initial_dda);
 125
 126         h_dda = (win->w * 0x1000) / max(win->out_w - 1, 1U);
 127         v_dda = (win->h * 0x1000) / max(win->out_h - 1, 1U);
 128
 129         val = h_dda << H_DDA_INC_SHIFT;
 130         val |= v_dda << V_DDA_INC_SHIFT;
 131         writel(val, &dc->win.dda_increment);
 132
 133         writel(win->stride, &dc->win.line_stride);
 134         writel(0, &dc->win.buf_stride);
 135
 136         val = WIN_ENABLE;
 137         if (win->bpp < 24)
 138                 val |= COLOR_EXPAND;
 139         writel(val, &dc->win.win_opt);
 140
 141         writel((unsigned long)win->phys_addr, &dc->winbuf.start_addr);
 142         writel(win->x, &dc->winbuf.addr_h_offset);
 143         writel(win->y, &dc->winbuf.addr_v_offset);
 144
 145         writel(0xff00, &dc->win.blend_nokey);
 146         writel(0xff00, &dc->win.blend_1win);
 147
 148         val = GENERAL_ACT_REQ | WIN_A_ACT_REQ;
 149         val |= GENERAL_UPDATE | WIN_A_UPDATE;
 150         writel(val, &dc->cmd.state_ctrl);
 151 }
 152
 153 static void write_pair(struct tegra_lcd_priv *priv, int item, u32 *reg)
 154 {
 155         writel(priv->horiz_timing[item] |
 156                         (priv->vert_timing[item] << 16), reg);
 157 }
 158
 159 static int update_display_mode(struct dc_disp_reg *disp,
 160                                struct tegra_lcd_priv *priv)
 161 {
 162         unsigned long val;
 163         unsigned long rate;
 164         unsigned long div;
 165
 166         writel(0x0, &disp->disp_timing_opt);
 167         write_pair(priv, FDT_LCD_TIMING_REF_TO_SYNC, &disp->ref_to_sync);
 168         write_pair(priv, FDT_LCD_TIMING_SYNC_WIDTH, &disp->sync_width);
 169         write_pair(priv, FDT_LCD_TIMING_BACK_PORCH, &disp->back_porch);
 170         write_pair(priv, FDT_LCD_TIMING_FRONT_PORCH, &disp->front_porch);
 171
 172         writel(priv->width | (priv->height << 16), &disp->disp_active);
 173
 174         val = DE_SELECT_ACTIVE << DE_SELECT_SHIFT;
 175         val |= DE_CONTROL_NORMAL << DE_CONTROL_SHIFT;
 176         writel(val, &disp->data_enable_opt);
 177
 178         val = DATA_FORMAT_DF1P1C << DATA_FORMAT_SHIFT;
 179         val |= DATA_ALIGNMENT_MSB << DATA_ALIGNMENT_SHIFT;
 180         val |= DATA_ORDER_RED_BLUE << DATA_ORDER_SHIFT;
 181         writel(val, &disp->disp_interface_ctrl);
 182
 183         /*
 184          * The pixel clock divider is in 7.1 format (where the bottom bit
 185          * represents 0.5). Here we calculate the divider needed to get from
 186          * the display clock (typically 600MHz) to the pixel clock. We round
 187          * up or down as requried.
 188          */
 189         rate = clock_get_periph_rate(PERIPH_ID_DISP1, CLOCK_ID_CGENERAL);
 190         div = ((rate * 2 + priv->pixel_clock / 2) / priv->pixel_clock) - 2;
 191         debug("Display clock %lu, divider %lu\n", rate, div);
 192
 193         writel(0x00010001, &disp->shift_clk_opt);
 194
 195         val = PIXEL_CLK_DIVIDER_PCD1 << PIXEL_CLK_DIVIDER_SHIFT;
 196         val |= div << SHIFT_CLK_DIVIDER_SHIFT;
 197         writel(val, &disp->disp_clk_ctrl);
 198
 199         return 0;
 200 }
 201
 202 /* Start up the display and turn on power to PWMs */
 203 static void basic_init(struct dc_cmd_reg *cmd)
 204 {
 205         u32 val;
 206
 207         writel(0x00000100, &cmd->gen_incr_syncpt_ctrl);
 208         writel(0x0000011a, &cmd->cont_syncpt_vsync);
 209         writel(0x00000000, &cmd->int_type);
 210         writel(0x00000000, &cmd->int_polarity);
 211         writel(0x00000000, &cmd->int_mask);
 212         writel(0x00000000, &cmd->int_enb);
 213
 214         val = PW0_ENABLE | PW1_ENABLE | PW2_ENABLE;
 215         val |= PW3_ENABLE | PW4_ENABLE | PM0_ENABLE;
 216         val |= PM1_ENABLE;
 217         writel(val, &cmd->disp_pow_ctrl);
 218
 219         val = readl(&cmd->disp_cmd);
 220         val |= CTRL_MODE_C_DISPLAY << CTRL_MODE_SHIFT;
 221         writel(val, &cmd->disp_cmd);
 222 }
 223
 224 static void basic_init_timer(struct dc_disp_reg *disp)
 225 {
 226         writel(0x00000020, &disp->mem_high_pri);
 227         writel(0x00000001, &disp->mem_high_pri_timer);
 228 }
 229
 230 static const u32 rgb_enb_tab[PIN_REG_COUNT] = {
 231         0x00000000,
 232         0x00000000,
 233         0x00000000,
 234         0x00000000,
 235 };
 236
 237 static const u32 rgb_polarity_tab[PIN_REG_COUNT] = {
 238         0x00000000,
 239         0x01000000,
 240         0x00000000,
 241         0x00000000,
 242 };
 243
 244 static const u32 rgb_data_tab[PIN_REG_COUNT] = {
 245         0x00000000,
 246         0x00000000,
 247         0x00000000,
 248         0x00000000,
 249 };
 250
 251 static const u32 rgb_sel_tab[PIN_OUTPUT_SEL_COUNT] = {
 252         0x00000000,
 253         0x00000000,
 254         0x00000000,
 255         0x00000000,
 256         0x00210222,
 257         0x00002200,
 258         0x00020000,
 259 };
 260
 261 static void rgb_enable(struct dc_com_reg *com)
 262 {
 263         int i;
 264
 265         for (i = 0; i < PIN_REG_COUNT; i++) {
 266                 writel(rgb_enb_tab[i], &com->pin_output_enb[i]);
 267                 writel(rgb_polarity_tab[i], &com->pin_output_polarity[i]);
 268                 writel(rgb_data_tab[i], &com->pin_output_data[i]);
 269         }
 270
 271         for (i = 0; i < PIN_OUTPUT_SEL_COUNT; i++)
 272                 writel(rgb_sel_tab[i], &com->pin_output_sel[i]);
 273 }
 274
 275 static int setup_window(struct disp_ctl_win *win,
 276                         struct tegra_lcd_priv *priv)
 277 {
 278         win->x = 0;
 279         win->y = 0;
 280         win->w = priv->width;
 281         win->h = priv->height;
 282         win->out_x = 0;
 283         win->out_y = 0;
 284         win->out_w = priv->width;
 285         win->out_h = priv->height;
 286         win->phys_addr = priv->frame_buffer;
 287         win->stride = priv->width * (1 << priv->log2_bpp) / 8;
 288         debug("%s: depth = %d\n", __func__, priv->log2_bpp);
 289         switch (priv->log2_bpp) {
 290         case 5:
 291         case 24:
 292                 win->fmt = COLOR_DEPTH_R8G8B8A8;
 293                 win->bpp = 32;
 294                 break;
 295         case 4:
 296                 win->fmt = COLOR_DEPTH_B5G6R5;
 297                 win->bpp = 16;
 298                 break;
 299
 300         default:
 301                 debug("Unsupported LCD bit depth");
 302                 return -1;
 303         }
 304
 305         return 0;
 306 }
 307
 308 static void debug_timing(const char *name, unsigned int timing[])
 309 {
 310 #ifdef DEBUG
 311         int i;
 312
 313         debug("%s timing: ", name);
 314         for (i = 0; i < FDT_LCD_TIMING_COUNT; i++)
 315                 debug("%d ", timing[i]);
 316         debug("\n");
 317 #endif
 318 }
 319
 320 /**
 321  * Register a new display based on device tree configuration.
 322  *
 323  * The frame buffer can be positioned by U-Boot or overriden by the fdt.
 324  * You should pass in the U-Boot address here, and check the contents of
 325  * struct tegra_lcd_priv to see what was actually chosen.
 326  *
 327  * @param blob                  Device tree blob
 328  * @param priv                  Driver's private data
 329  * @param default_lcd_base      Default address of LCD frame buffer
 330  * @return 0 if ok, -1 on error (unsupported bits per pixel)
 331  */
 332 static int tegra_display_probe(const void *blob, struct tegra_lcd_priv *priv,
 333                                void *default_lcd_base)
 334 {
 335         struct disp_ctl_win window;
 336         struct dc_ctlr *dc;
 337
 338         priv->frame_buffer = (u32)default_lcd_base;
 339
 340         dc = (struct dc_ctlr *)priv->disp;
 341
 342         /*
 343          * A header file for clock constants was NAKed upstream.
 344          * TODO: Put this into the FDT and fdt_lcd struct when we have clock
 345          * support there
 346          */
 347         clock_start_periph_pll(PERIPH_ID_HOST1X, CLOCK_ID_PERIPH,
 348                                144 * 1000000);
 349         clock_start_periph_pll(PERIPH_ID_DISP1, CLOCK_ID_CGENERAL,
 350                                600 * 1000000);
 351         basic_init(&dc->cmd);
 352         basic_init_timer(&dc->disp);
 353         rgb_enable(&dc->com);
 354
 355         if (priv->pixel_clock)
 356                 update_display_mode(&dc->disp, priv);
 357
 358         if (setup_window(&window, priv))
 359                 return -1;
 360
 361         update_window(dc, &window);
 362
 363         return 0;
 364 }
 365
 366 /**
 367  * Handle the next stage of device init
 368  */
 369 static int handle_stage(const void *blob, struct tegra_lcd_priv *priv)
 370 {
 371         debug("%s: stage %d\n", __func__, priv->stage);
 372
 373         /* do the things for this stage */
 374         switch (priv->stage) {
 375         case STAGE_START:
 376                 /*
 377                  * It is possible that the FDT has requested that the LCD be
 378                  * disabled. We currently don't support this. It would require
 379                  * changes to U-Boot LCD subsystem to have LCD support
 380                  * compiled in but not used. An easier option might be to
 381                  * still have a frame buffer, but leave the backlight off and
 382                  * remove all mention of lcd in the stdout environment
 383                  * variable.
 384                  */
 385
 386                 funcmux_select(PERIPH_ID_DISP1, FUNCMUX_DEFAULT);
 387                 break;
 388         case STAGE_PANEL_VDD:
 389                 if (dm_gpio_is_valid(&priv->panel_vdd))
 390                         dm_gpio_set_value(&priv->panel_vdd, 1);
 391                 break;
 392         case STAGE_LVDS:
 393                 if (dm_gpio_is_valid(&priv->lvds_shutdown))
 394                         dm_gpio_set_value(&priv->lvds_shutdown, 1);
 395                 break;
 396         case STAGE_BACKLIGHT_VDD:
 397                 if (dm_gpio_is_valid(&priv->backlight_vdd))
 398                         dm_gpio_set_value(&priv->backlight_vdd, 1);
 399                 break;
 400         case STAGE_PWM:
 401                 /* Enable PWM at 15/16 high, 32768 Hz with divider 1 */
 402                 pinmux_set_func(PMUX_PINGRP_GPU, PMUX_FUNC_PWM);
 403                 pinmux_tristate_disable(PMUX_PINGRP_GPU);
 404
 405                 pwm_set_config(priv->pwm, priv->pwm_channel, 0xdf, 0xff);
 406                 pwm_set_enable(priv->pwm, priv->pwm_channel, true);
 407                 break;
 408         case STAGE_BACKLIGHT_EN:
 409                 if (dm_gpio_is_valid(&priv->backlight_en))
 410                         dm_gpio_set_value(&priv->backlight_en, 1);
 411                 break;
 412         case STAGE_DONE:
 413                 break;
 414         }
 415
 416         /* set up timer for next stage */
 417         priv->timer_next = timer_get_us();
 418         if (priv->stage < FDT_LCD_TIMINGS)
 419                 priv->timer_next += priv->panel_timings[priv->stage] * 1000;
 420
 421         /* move to next stage */
 422         priv->stage++;
 423         return 0;
 424 }
 425
 426 /**
 427  * Perform the next stage of the LCD init if it is time to do so.
 428  *
 429  * LCD init can be time-consuming because of the number of delays we need
 430  * while waiting for the backlight power supply, etc. This function can
 431  * be called at various times during U-Boot operation to advance the
 432  * initialization of the LCD to the next stage if sufficient time has
 433  * passed since the last stage. It keeps track of what stage it is up to
 434  * and the time that it is permitted to move to the next stage.
 435  *
 436  * The final call should have wait=1 to complete the init.
 437  *
 438  * @param blob  fdt blob containing LCD information
 439  * @param wait  1 to wait until all init is complete, and then return
 440  *              0 to return immediately, potentially doing nothing if it is
 441  *              not yet time for the next init.
 442  */
 443 static int tegra_lcd_check_next_stage(const void *blob,
 444                                       struct tegra_lcd_priv *priv, int wait)
 445 {
 446         if (priv->stage == STAGE_DONE)
 447                 return 0;
 448
 449         do {
 450                 /* wait if we need to */
 451                 debug("%s: stage %d\n", __func__, priv->stage);
 452                 if (priv->stage != STAGE_START) {
 453                         int delay = priv->timer_next - timer_get_us();
 454
 455                         if (delay > 0) {
 456                                 if (wait)
 457                                         udelay(delay);
 458                                 else
 459                                         return 0;
 460                         }
 461                 }
 462
 463                 if (handle_stage(blob, priv))
 464                         return -1;
 465         } while (wait && priv->stage != STAGE_DONE);
 466         if (priv->stage == STAGE_DONE)
 467                 debug("%s: LCD init complete\n", __func__);
 468
 469         return 0;
 470 }
 471
 472 static int tegra_lcd_probe(struct udevice *dev)
 473 {
 474         struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
 475         struct video_priv *uc_priv = dev_get_uclass_priv(dev);
 476         struct tegra_lcd_priv *priv = dev_get_priv(dev);
 477         const void *blob = gd->fdt_blob;
 478         int type = DCACHE_OFF;
 479
 480         /* Initialize the Tegra display controller */
 481         if (tegra_display_probe(blob, priv, (void *)plat->base)) {
 482                 printf("%s: Failed to probe display driver\n", __func__);
 483                 return -1;
 484         }
 485
 486         tegra_lcd_check_next_stage(blob, priv, 1);
 487
 488         /* Set up the LCD caching as requested */
 489         if (priv->cache_type & FDT_LCD_CACHE_WRITE_THROUGH)
 490                 type = DCACHE_WRITETHROUGH;
 491         else if (priv->cache_type & FDT_LCD_CACHE_WRITE_BACK)
 492                 type = DCACHE_WRITEBACK;
 493         mmu_set_region_dcache_behaviour(priv->frame_buffer, plat->size, type);
 494
 495         /* Enable flushing after LCD writes if requested */
 496         video_set_flush_dcache(dev, priv->cache_type & FDT_LCD_CACHE_FLUSH);
 497
 498         uc_priv->xsize = priv->width;
 499         uc_priv->ysize = priv->height;
 500         uc_priv->bpix = priv->log2_bpp;
 501         debug("LCD frame buffer at %pa, size %x\n", &priv->frame_buffer,
 502               plat->size);
 503
 504         return 0;
 505 }
 506
 507 static int tegra_lcd_ofdata_to_platdata(struct udevice *dev)
 508 {
 509         struct tegra_lcd_priv *priv = dev_get_priv(dev);
 510         struct fdtdec_phandle_args args;
 511         const void *blob = gd->fdt_blob;
 512         int node = dev->of_offset;
 513         int front, back, ref;
 514         int panel_node;
 515         int rgb;
 516         int bpp, bit;
 517         int ret;
 518
 519         priv->disp = (struct disp_ctlr *)dev_get_addr(dev);
 520         if (!priv->disp) {
 521                 debug("%s: No display controller address\n", __func__);
 522                 return -EINVAL;
 523         }
 524
 525         rgb = fdt_subnode_offset(blob, node, "rgb");
 526
 527         panel_node = fdtdec_lookup_phandle(blob, rgb, "nvidia,panel");
 528         if (panel_node < 0) {
 529                 debug("%s: Cannot find panel information\n", __func__);
 530                 return -EINVAL;
 531         }
 532
 533         priv->width = fdtdec_get_int(blob, panel_node, "xres", -1);
 534         priv->height = fdtdec_get_int(blob, panel_node, "yres", -1);
 535         priv->pixel_clock = fdtdec_get_int(blob, panel_node, "clock", 0);
 536         if (!priv->pixel_clock || priv->width == -1 || priv->height == -1) {
 537                 debug("%s: Pixel parameters missing\n", __func__);
 538                 return -EINVAL;
 539         }
 540
 541         back = fdtdec_get_int(blob, panel_node, "left-margin", -1);
 542         front = fdtdec_get_int(blob, panel_node, "right-margin", -1);
 543         ref = fdtdec_get_int(blob, panel_node, "hsync-len", -1);
 544         if ((back | front | ref) == -1) {
 545                 debug("%s: Horizontal parameters missing\n", __func__);
 546                 return -EINVAL;
 547         }
 548
 549         /* Use a ref-to-sync of 1 always, and take this from the front porch */
 550         priv->horiz_timing[FDT_LCD_TIMING_REF_TO_SYNC] = 1;
 551         priv->horiz_timing[FDT_LCD_TIMING_SYNC_WIDTH] = ref;
 552         priv->horiz_timing[FDT_LCD_TIMING_BACK_PORCH] = back;
 553         priv->horiz_timing[FDT_LCD_TIMING_FRONT_PORCH] = front -
 554                 priv->horiz_timing[FDT_LCD_TIMING_REF_TO_SYNC];
 555         debug_timing("horiz", priv->horiz_timing);
 556
 557         back = fdtdec_get_int(blob, panel_node, "upper-margin", -1);
 558         front = fdtdec_get_int(blob, panel_node, "lower-margin", -1);
 559         ref = fdtdec_get_int(blob, panel_node, "vsync-len", -1);
 560         if ((back | front | ref) == -1) {
 561                 debug("%s: Vertical parameters missing\n", __func__);
 562                 return -EINVAL;
 563         }
 564
 565         priv->vert_timing[FDT_LCD_TIMING_REF_TO_SYNC] = 1;
 566         priv->vert_timing[FDT_LCD_TIMING_SYNC_WIDTH] = ref;
 567         priv->vert_timing[FDT_LCD_TIMING_BACK_PORCH] = back;
 568         priv->vert_timing[FDT_LCD_TIMING_FRONT_PORCH] = front -
 569                 priv->vert_timing[FDT_LCD_TIMING_REF_TO_SYNC];
 570         debug_timing("vert", priv->vert_timing);
 571
 572         bpp = fdtdec_get_int(blob, panel_node, "nvidia,bits-per-pixel", -1);
 573         bit = ffs(bpp) - 1;
 574         if (bpp == (1 << bit))
 575                 priv->log2_bpp = bit;
 576         else
 577                 priv->log2_bpp = bpp;
 578         if (bpp == -1) {
 579                 debug("%s: Pixel bpp parameters missing\n", __func__);
 580                 return -EINVAL;
 581         }
 582
 583         if (fdtdec_parse_phandle_with_args(blob, panel_node, "nvidia,pwm",
 584                                            "#pwm-cells", 0, 0, &args)) {
 585                 debug("%s: Unable to decode PWM\n", __func__);
 586                 return -EINVAL;
 587         }
 588
 589         ret = uclass_get_device_by_of_offset(UCLASS_PWM, args.node, &priv->pwm);
 590         if (ret) {
 591                 debug("%s: Unable to find PWM\n", __func__);
 592                 return -EINVAL;
 593         }
 594         priv->pwm_channel = args.args[0];
 595
 596         priv->cache_type = fdtdec_get_int(blob, panel_node, "nvidia,cache-type",
 597                                           FDT_LCD_CACHE_WRITE_BACK_FLUSH);
 598
 599         /* These GPIOs are all optional */
 600         gpio_request_by_name_nodev(blob, panel_node,
 601                                    "nvidia,backlight-enable-gpios", 0,
 602                                    &priv->backlight_en, GPIOD_IS_OUT);
 603         gpio_request_by_name_nodev(blob, panel_node,
 604                                    "nvidia,lvds-shutdown-gpios", 0,
 605                                    &priv->lvds_shutdown, GPIOD_IS_OUT);
 606         gpio_request_by_name_nodev(blob, panel_node,
 607                                    "nvidia,backlight-vdd-gpios", 0,
 608                                    &priv->backlight_vdd, GPIOD_IS_OUT);
 609         gpio_request_by_name_nodev(blob, panel_node,
 610                                    "nvidia,panel-vdd-gpios", 0,
 611                                    &priv->panel_vdd, GPIOD_IS_OUT);
 612
 613         if (fdtdec_get_int_array(blob, panel_node, "nvidia,panel-timings",
 614                                  priv->panel_timings, FDT_LCD_TIMINGS))
 615                 return -EINVAL;
 616
 617         return 0;
 618 }
 619
 620 static int tegra_lcd_bind(struct udevice *dev)
 621 {
 622         struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
 623
 624         plat->size = LCD_MAX_WIDTH * LCD_MAX_HEIGHT *
 625                 (1 << LCD_MAX_LOG2_BPP) / 8;
 626
 627         return 0;
 628 }
 629
 630 static const struct video_ops tegra_lcd_ops = {
 631 };
 632
 633 static const struct udevice_id tegra_lcd_ids[] = {
 634         { .compatible = "nvidia,tegra20-dc" },
 635         { }
 636 };
 637
 638 U_BOOT_DRIVER(tegra_lcd) = {
 639         .name   = "tegra_lcd",
 640         .id     = UCLASS_VIDEO,
 641         .of_match = tegra_lcd_ids,
 642         .ops    = &tegra_lcd_ops,
 643         .bind   = tegra_lcd_bind,
 644         .probe  = tegra_lcd_probe,
 645         .ofdata_to_platdata     = tegra_lcd_ofdata_to_platdata,
 646         .priv_auto_alloc_size   = sizeof(struct tegra_lcd_priv),
 647 };