xref: /rk3399_rockchip-uboot/drivers/video/tegra.c (revision f20b2c067160a38b4cc9da277cc03c95aa972e63)
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 <video.h>
10 #include <asm/system.h>
11 #include <asm/gpio.h>
12 #include <asm/io.h>
13 
14 #include <asm/arch/clock.h>
15 #include <asm/arch/funcmux.h>
16 #include <asm/arch/pinmux.h>
17 #include <asm/arch/pwm.h>
18 #include <asm/arch/display.h>
19 #include <asm/arch-tegra/timer.h>
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 /* These are the stages we go throuh in enabling the LCD */
24 enum stage_t {
25 	STAGE_START,
26 	STAGE_PANEL_VDD,
27 	STAGE_LVDS,
28 	STAGE_BACKLIGHT_VDD,
29 	STAGE_PWM,
30 	STAGE_BACKLIGHT_EN,
31 	STAGE_DONE,
32 };
33 
34 /* Information about the display controller */
35 struct tegra_lcd_priv {
36 	enum stage_t stage;	/* Current stage we are at */
37 	unsigned long timer_next; /* Time we can move onto next stage */
38 	int width;			/* width in pixels */
39 	int height;			/* height in pixels */
40 	int bpp;			/* number of bits per pixel */
41 
42 	/*
43 	 * log2 of number of bpp, in general, unless it bpp is 24 in which
44 	 * case this field holds 24 also! This is a U-Boot thing.
45 	 */
46 	int log2_bpp;
47 	struct disp_ctlr *disp;		/* Display controller to use */
48 	fdt_addr_t frame_buffer;	/* Address of frame buffer */
49 	unsigned pixel_clock;		/* Pixel clock in Hz */
50 	uint horiz_timing[FDT_LCD_TIMING_COUNT];	/* Horizontal timing */
51 	uint vert_timing[FDT_LCD_TIMING_COUNT];		/* Vertical timing */
52 	int panel_node;			/* node offset of panel information */
53 	int pwm_channel;		/* PWM channel to use for backlight */
54 	enum lcd_cache_t cache_type;
55 
56 	struct gpio_desc backlight_en;	/* GPIO for backlight enable */
57 	struct gpio_desc lvds_shutdown;	/* GPIO for lvds shutdown */
58 	struct gpio_desc backlight_vdd;	/* GPIO for backlight vdd */
59 	struct gpio_desc panel_vdd;	/* GPIO for panel vdd */
60 	/*
61 	 * Panel required timings
62 	 * Timing 1: delay between panel_vdd-rise and data-rise
63 	 * Timing 2: delay between data-rise and backlight_vdd-rise
64 	 * Timing 3: delay between backlight_vdd and pwm-rise
65 	 * Timing 4: delay between pwm-rise and backlight_en-rise
66 	 */
67 	uint panel_timings[FDT_LCD_TIMINGS];
68 };
69 
70 enum {
71 	/* Maximum LCD size we support */
72 	LCD_MAX_WIDTH		= 1366,
73 	LCD_MAX_HEIGHT		= 768,
74 	LCD_MAX_LOG2_BPP	= VIDEO_BPP16,
75 };
76 
77 static void update_window(struct dc_ctlr *dc, struct disp_ctl_win *win)
78 {
79 	unsigned h_dda, v_dda;
80 	unsigned long val;
81 
82 	val = readl(&dc->cmd.disp_win_header);
83 	val |= WINDOW_A_SELECT;
84 	writel(val, &dc->cmd.disp_win_header);
85 
86 	writel(win->fmt, &dc->win.color_depth);
87 
88 	clrsetbits_le32(&dc->win.byte_swap, BYTE_SWAP_MASK,
89 			BYTE_SWAP_NOSWAP << BYTE_SWAP_SHIFT);
90 
91 	val = win->out_x << H_POSITION_SHIFT;
92 	val |= win->out_y << V_POSITION_SHIFT;
93 	writel(val, &dc->win.pos);
94 
95 	val = win->out_w << H_SIZE_SHIFT;
96 	val |= win->out_h << V_SIZE_SHIFT;
97 	writel(val, &dc->win.size);
98 
99 	val = (win->w * win->bpp / 8) << H_PRESCALED_SIZE_SHIFT;
100 	val |= win->h << V_PRESCALED_SIZE_SHIFT;
101 	writel(val, &dc->win.prescaled_size);
102 
103 	writel(0, &dc->win.h_initial_dda);
104 	writel(0, &dc->win.v_initial_dda);
105 
106 	h_dda = (win->w * 0x1000) / max(win->out_w - 1, 1U);
107 	v_dda = (win->h * 0x1000) / max(win->out_h - 1, 1U);
108 
109 	val = h_dda << H_DDA_INC_SHIFT;
110 	val |= v_dda << V_DDA_INC_SHIFT;
111 	writel(val, &dc->win.dda_increment);
112 
113 	writel(win->stride, &dc->win.line_stride);
114 	writel(0, &dc->win.buf_stride);
115 
116 	val = WIN_ENABLE;
117 	if (win->bpp < 24)
118 		val |= COLOR_EXPAND;
119 	writel(val, &dc->win.win_opt);
120 
121 	writel((unsigned long)win->phys_addr, &dc->winbuf.start_addr);
122 	writel(win->x, &dc->winbuf.addr_h_offset);
123 	writel(win->y, &dc->winbuf.addr_v_offset);
124 
125 	writel(0xff00, &dc->win.blend_nokey);
126 	writel(0xff00, &dc->win.blend_1win);
127 
128 	val = GENERAL_ACT_REQ | WIN_A_ACT_REQ;
129 	val |= GENERAL_UPDATE | WIN_A_UPDATE;
130 	writel(val, &dc->cmd.state_ctrl);
131 }
132 
133 static void write_pair(struct tegra_lcd_priv *priv, int item, u32 *reg)
134 {
135 	writel(priv->horiz_timing[item] |
136 			(priv->vert_timing[item] << 16), reg);
137 }
138 
139 static int update_display_mode(struct dc_disp_reg *disp,
140 			       struct tegra_lcd_priv *priv)
141 {
142 	unsigned long val;
143 	unsigned long rate;
144 	unsigned long div;
145 
146 	writel(0x0, &disp->disp_timing_opt);
147 	write_pair(priv, FDT_LCD_TIMING_REF_TO_SYNC, &disp->ref_to_sync);
148 	write_pair(priv, FDT_LCD_TIMING_SYNC_WIDTH, &disp->sync_width);
149 	write_pair(priv, FDT_LCD_TIMING_BACK_PORCH, &disp->back_porch);
150 	write_pair(priv, FDT_LCD_TIMING_FRONT_PORCH, &disp->front_porch);
151 
152 	writel(priv->width | (priv->height << 16), &disp->disp_active);
153 
154 	val = DE_SELECT_ACTIVE << DE_SELECT_SHIFT;
155 	val |= DE_CONTROL_NORMAL << DE_CONTROL_SHIFT;
156 	writel(val, &disp->data_enable_opt);
157 
158 	val = DATA_FORMAT_DF1P1C << DATA_FORMAT_SHIFT;
159 	val |= DATA_ALIGNMENT_MSB << DATA_ALIGNMENT_SHIFT;
160 	val |= DATA_ORDER_RED_BLUE << DATA_ORDER_SHIFT;
161 	writel(val, &disp->disp_interface_ctrl);
162 
163 	/*
164 	 * The pixel clock divider is in 7.1 format (where the bottom bit
165 	 * represents 0.5). Here we calculate the divider needed to get from
166 	 * the display clock (typically 600MHz) to the pixel clock. We round
167 	 * up or down as requried.
168 	 */
169 	rate = clock_get_periph_rate(PERIPH_ID_DISP1, CLOCK_ID_CGENERAL);
170 	div = ((rate * 2 + priv->pixel_clock / 2) / priv->pixel_clock) - 2;
171 	debug("Display clock %lu, divider %lu\n", rate, div);
172 
173 	writel(0x00010001, &disp->shift_clk_opt);
174 
175 	val = PIXEL_CLK_DIVIDER_PCD1 << PIXEL_CLK_DIVIDER_SHIFT;
176 	val |= div << SHIFT_CLK_DIVIDER_SHIFT;
177 	writel(val, &disp->disp_clk_ctrl);
178 
179 	return 0;
180 }
181 
182 /* Start up the display and turn on power to PWMs */
183 static void basic_init(struct dc_cmd_reg *cmd)
184 {
185 	u32 val;
186 
187 	writel(0x00000100, &cmd->gen_incr_syncpt_ctrl);
188 	writel(0x0000011a, &cmd->cont_syncpt_vsync);
189 	writel(0x00000000, &cmd->int_type);
190 	writel(0x00000000, &cmd->int_polarity);
191 	writel(0x00000000, &cmd->int_mask);
192 	writel(0x00000000, &cmd->int_enb);
193 
194 	val = PW0_ENABLE | PW1_ENABLE | PW2_ENABLE;
195 	val |= PW3_ENABLE | PW4_ENABLE | PM0_ENABLE;
196 	val |= PM1_ENABLE;
197 	writel(val, &cmd->disp_pow_ctrl);
198 
199 	val = readl(&cmd->disp_cmd);
200 	val |= CTRL_MODE_C_DISPLAY << CTRL_MODE_SHIFT;
201 	writel(val, &cmd->disp_cmd);
202 }
203 
204 static void basic_init_timer(struct dc_disp_reg *disp)
205 {
206 	writel(0x00000020, &disp->mem_high_pri);
207 	writel(0x00000001, &disp->mem_high_pri_timer);
208 }
209 
210 static const u32 rgb_enb_tab[PIN_REG_COUNT] = {
211 	0x00000000,
212 	0x00000000,
213 	0x00000000,
214 	0x00000000,
215 };
216 
217 static const u32 rgb_polarity_tab[PIN_REG_COUNT] = {
218 	0x00000000,
219 	0x01000000,
220 	0x00000000,
221 	0x00000000,
222 };
223 
224 static const u32 rgb_data_tab[PIN_REG_COUNT] = {
225 	0x00000000,
226 	0x00000000,
227 	0x00000000,
228 	0x00000000,
229 };
230 
231 static const u32 rgb_sel_tab[PIN_OUTPUT_SEL_COUNT] = {
232 	0x00000000,
233 	0x00000000,
234 	0x00000000,
235 	0x00000000,
236 	0x00210222,
237 	0x00002200,
238 	0x00020000,
239 };
240 
241 static void rgb_enable(struct dc_com_reg *com)
242 {
243 	int i;
244 
245 	for (i = 0; i < PIN_REG_COUNT; i++) {
246 		writel(rgb_enb_tab[i], &com->pin_output_enb[i]);
247 		writel(rgb_polarity_tab[i], &com->pin_output_polarity[i]);
248 		writel(rgb_data_tab[i], &com->pin_output_data[i]);
249 	}
250 
251 	for (i = 0; i < PIN_OUTPUT_SEL_COUNT; i++)
252 		writel(rgb_sel_tab[i], &com->pin_output_sel[i]);
253 }
254 
255 static int setup_window(struct disp_ctl_win *win,
256 			struct tegra_lcd_priv *priv)
257 {
258 	win->x = 0;
259 	win->y = 0;
260 	win->w = priv->width;
261 	win->h = priv->height;
262 	win->out_x = 0;
263 	win->out_y = 0;
264 	win->out_w = priv->width;
265 	win->out_h = priv->height;
266 	win->phys_addr = priv->frame_buffer;
267 	win->stride = priv->width * (1 << priv->log2_bpp) / 8;
268 	debug("%s: depth = %d\n", __func__, priv->log2_bpp);
269 	switch (priv->log2_bpp) {
270 	case 5:
271 	case 24:
272 		win->fmt = COLOR_DEPTH_R8G8B8A8;
273 		win->bpp = 32;
274 		break;
275 	case 4:
276 		win->fmt = COLOR_DEPTH_B5G6R5;
277 		win->bpp = 16;
278 		break;
279 
280 	default:
281 		debug("Unsupported LCD bit depth");
282 		return -1;
283 	}
284 
285 	return 0;
286 }
287 
288 static void debug_timing(const char *name, unsigned int timing[])
289 {
290 #ifdef DEBUG
291 	int i;
292 
293 	debug("%s timing: ", name);
294 	for (i = 0; i < FDT_LCD_TIMING_COUNT; i++)
295 		debug("%d ", timing[i]);
296 	debug("\n");
297 #endif
298 }
299 
300 /**
301  * Decode panel information from the fdt, according to a standard binding
302  *
303  * @param blob		fdt blob
304  * @param node		offset of fdt node to read from
305  * @param priv		structure to store fdt config into
306  * @return 0 if ok, -ve on error
307  */
308 static int tegra_decode_panel(const void *blob, int node,
309 			      struct tegra_lcd_priv *priv)
310 {
311 	int front, back, ref;
312 
313 	priv->width = fdtdec_get_int(blob, node, "xres", -1);
314 	priv->height = fdtdec_get_int(blob, node, "yres", -1);
315 	priv->pixel_clock = fdtdec_get_int(blob, node, "clock", 0);
316 	if (!priv->pixel_clock || priv->width == -1 || priv->height == -1) {
317 		debug("%s: Pixel parameters missing\n", __func__);
318 		return -FDT_ERR_NOTFOUND;
319 	}
320 
321 	back = fdtdec_get_int(blob, node, "left-margin", -1);
322 	front = fdtdec_get_int(blob, node, "right-margin", -1);
323 	ref = fdtdec_get_int(blob, node, "hsync-len", -1);
324 	if ((back | front | ref) == -1) {
325 		debug("%s: Horizontal parameters missing\n", __func__);
326 		return -FDT_ERR_NOTFOUND;
327 	}
328 
329 	/* Use a ref-to-sync of 1 always, and take this from the front porch */
330 	priv->horiz_timing[FDT_LCD_TIMING_REF_TO_SYNC] = 1;
331 	priv->horiz_timing[FDT_LCD_TIMING_SYNC_WIDTH] = ref;
332 	priv->horiz_timing[FDT_LCD_TIMING_BACK_PORCH] = back;
333 	priv->horiz_timing[FDT_LCD_TIMING_FRONT_PORCH] = front -
334 		priv->horiz_timing[FDT_LCD_TIMING_REF_TO_SYNC];
335 	debug_timing("horiz", priv->horiz_timing);
336 
337 	back = fdtdec_get_int(blob, node, "upper-margin", -1);
338 	front = fdtdec_get_int(blob, node, "lower-margin", -1);
339 	ref = fdtdec_get_int(blob, node, "vsync-len", -1);
340 	if ((back | front | ref) == -1) {
341 		debug("%s: Vertical parameters missing\n", __func__);
342 		return -FDT_ERR_NOTFOUND;
343 	}
344 
345 	priv->vert_timing[FDT_LCD_TIMING_REF_TO_SYNC] = 1;
346 	priv->vert_timing[FDT_LCD_TIMING_SYNC_WIDTH] = ref;
347 	priv->vert_timing[FDT_LCD_TIMING_BACK_PORCH] = back;
348 	priv->vert_timing[FDT_LCD_TIMING_FRONT_PORCH] = front -
349 		priv->vert_timing[FDT_LCD_TIMING_REF_TO_SYNC];
350 	debug_timing("vert", priv->vert_timing);
351 
352 	return 0;
353 }
354 
355 /**
356  * Decode the display controller information from the fdt.
357  *
358  * @param blob		fdt blob
359  * @param priv		structure to store fdt priv into
360  * @return 0 if ok, -ve on error
361  */
362 static int tegra_display_decode_config(const void *blob, int node,
363 				       struct tegra_lcd_priv *priv)
364 {
365 	int rgb;
366 	int bpp, bit;
367 
368 	priv->disp = (struct disp_ctlr *)fdtdec_get_addr(blob, node, "reg");
369 	if (!priv->disp) {
370 		debug("%s: No display controller address\n", __func__);
371 		return -1;
372 	}
373 
374 	rgb = fdt_subnode_offset(blob, node, "rgb");
375 
376 	priv->panel_node = fdtdec_lookup_phandle(blob, rgb, "nvidia,panel");
377 	if (priv->panel_node < 0) {
378 		debug("%s: Cannot find panel information\n", __func__);
379 		return -1;
380 	}
381 
382 	if (tegra_decode_panel(blob, priv->panel_node, priv)) {
383 		debug("%s: Failed to decode panel information\n", __func__);
384 		return -1;
385 	}
386 
387 	bpp = fdtdec_get_int(blob, priv->panel_node, "nvidia,bits-per-pixel",
388 			     -1);
389 	bit = ffs(bpp) - 1;
390 	if (bpp == (1 << bit))
391 		priv->log2_bpp = bit;
392 	else
393 		priv->log2_bpp = bpp;
394 	if (bpp == -1) {
395 		debug("%s: Pixel bpp parameters missing\n", __func__);
396 		return -FDT_ERR_NOTFOUND;
397 	}
398 	priv->bpp = bpp;
399 
400 	return 0;
401 }
402 
403 /**
404  * Register a new display based on device tree configuration.
405  *
406  * The frame buffer can be positioned by U-Boot or overriden by the fdt.
407  * You should pass in the U-Boot address here, and check the contents of
408  * struct tegra_lcd_priv to see what was actually chosen.
409  *
410  * @param blob			Device tree blob
411  * @param priv			Driver's private data
412  * @param default_lcd_base	Default address of LCD frame buffer
413  * @return 0 if ok, -1 on error (unsupported bits per pixel)
414  */
415 static int tegra_display_probe(const void *blob, struct tegra_lcd_priv *priv,
416 			       void *default_lcd_base)
417 {
418 	struct disp_ctl_win window;
419 	struct dc_ctlr *dc;
420 
421 	priv->frame_buffer = (u32)default_lcd_base;
422 
423 	dc = (struct dc_ctlr *)priv->disp;
424 
425 	/*
426 	 * A header file for clock constants was NAKed upstream.
427 	 * TODO: Put this into the FDT and fdt_lcd struct when we have clock
428 	 * support there
429 	 */
430 	clock_start_periph_pll(PERIPH_ID_HOST1X, CLOCK_ID_PERIPH,
431 			       144 * 1000000);
432 	clock_start_periph_pll(PERIPH_ID_DISP1, CLOCK_ID_CGENERAL,
433 			       600 * 1000000);
434 	basic_init(&dc->cmd);
435 	basic_init_timer(&dc->disp);
436 	rgb_enable(&dc->com);
437 
438 	if (priv->pixel_clock)
439 		update_display_mode(&dc->disp, priv);
440 
441 	if (setup_window(&window, priv))
442 		return -1;
443 
444 	update_window(dc, &window);
445 
446 	return 0;
447 }
448 
449 /**
450  * Decode the panel information from the fdt.
451  *
452  * @param blob		fdt blob
453  * @param priv		structure to store fdt config into
454  * @return 0 if ok, -ve on error
455  */
456 static int fdt_decode_lcd(const void *blob, struct tegra_lcd_priv *priv)
457 {
458 	int display_node;
459 
460 	display_node = priv->panel_node;
461 	if (display_node < 0) {
462 		debug("%s: No panel configuration available\n", __func__);
463 		return -1;
464 	}
465 
466 	priv->pwm_channel = pwm_request(blob, display_node, "nvidia,pwm");
467 	if (priv->pwm_channel < 0) {
468 		debug("%s: Unable to request PWM channel\n", __func__);
469 		return -1;
470 	}
471 
472 	priv->cache_type = fdtdec_get_int(blob, display_node,
473 					    "nvidia,cache-type",
474 					    FDT_LCD_CACHE_WRITE_BACK_FLUSH);
475 
476 	/* These GPIOs are all optional */
477 	gpio_request_by_name_nodev(blob, display_node,
478 				   "nvidia,backlight-enable-gpios", 0,
479 				   &priv->backlight_en, GPIOD_IS_OUT);
480 	gpio_request_by_name_nodev(blob, display_node,
481 				   "nvidia,lvds-shutdown-gpios", 0,
482 				   &priv->lvds_shutdown, GPIOD_IS_OUT);
483 	gpio_request_by_name_nodev(blob, display_node,
484 				   "nvidia,backlight-vdd-gpios", 0,
485 				   &priv->backlight_vdd, GPIOD_IS_OUT);
486 	gpio_request_by_name_nodev(blob, display_node,
487 				   "nvidia,panel-vdd-gpios", 0,
488 				   &priv->panel_vdd, GPIOD_IS_OUT);
489 
490 	return fdtdec_get_int_array(blob, display_node, "nvidia,panel-timings",
491 			priv->panel_timings, FDT_LCD_TIMINGS);
492 }
493 
494 /**
495  * Handle the next stage of device init
496  */
497 static int handle_stage(const void *blob, struct tegra_lcd_priv *priv)
498 {
499 	debug("%s: stage %d\n", __func__, priv->stage);
500 
501 	/* do the things for this stage */
502 	switch (priv->stage) {
503 	case STAGE_START:
504 		/*
505 		 * It is possible that the FDT has requested that the LCD be
506 		 * disabled. We currently don't support this. It would require
507 		 * changes to U-Boot LCD subsystem to have LCD support
508 		 * compiled in but not used. An easier option might be to
509 		 * still have a frame buffer, but leave the backlight off and
510 		 * remove all mention of lcd in the stdout environment
511 		 * variable.
512 		 */
513 
514 		funcmux_select(PERIPH_ID_DISP1, FUNCMUX_DEFAULT);
515 		break;
516 	case STAGE_PANEL_VDD:
517 		if (dm_gpio_is_valid(&priv->panel_vdd))
518 			dm_gpio_set_value(&priv->panel_vdd, 1);
519 		break;
520 	case STAGE_LVDS:
521 		if (dm_gpio_is_valid(&priv->lvds_shutdown))
522 			dm_gpio_set_value(&priv->lvds_shutdown, 1);
523 		break;
524 	case STAGE_BACKLIGHT_VDD:
525 		if (dm_gpio_is_valid(&priv->backlight_vdd))
526 			dm_gpio_set_value(&priv->backlight_vdd, 1);
527 		break;
528 	case STAGE_PWM:
529 		/* Enable PWM at 15/16 high, 32768 Hz with divider 1 */
530 		pinmux_set_func(PMUX_PINGRP_GPU, PMUX_FUNC_PWM);
531 		pinmux_tristate_disable(PMUX_PINGRP_GPU);
532 
533 		pwm_enable(priv->pwm_channel, 32768, 0xdf, 1);
534 		break;
535 	case STAGE_BACKLIGHT_EN:
536 		if (dm_gpio_is_valid(&priv->backlight_en))
537 			dm_gpio_set_value(&priv->backlight_en, 1);
538 		break;
539 	case STAGE_DONE:
540 		break;
541 	}
542 
543 	/* set up timer for next stage */
544 	priv->timer_next = timer_get_us();
545 	if (priv->stage < FDT_LCD_TIMINGS)
546 		priv->timer_next += priv->panel_timings[priv->stage] * 1000;
547 
548 	/* move to next stage */
549 	priv->stage++;
550 	return 0;
551 }
552 
553 /**
554  * Perform the next stage of the LCD init if it is time to do so.
555  *
556  * LCD init can be time-consuming because of the number of delays we need
557  * while waiting for the backlight power supply, etc. This function can
558  * be called at various times during U-Boot operation to advance the
559  * initialization of the LCD to the next stage if sufficient time has
560  * passed since the last stage. It keeps track of what stage it is up to
561  * and the time that it is permitted to move to the next stage.
562  *
563  * The final call should have wait=1 to complete the init.
564  *
565  * @param blob	fdt blob containing LCD information
566  * @param wait	1 to wait until all init is complete, and then return
567  *		0 to return immediately, potentially doing nothing if it is
568  *		not yet time for the next init.
569  */
570 static int tegra_lcd_check_next_stage(const void *blob,
571 				      struct tegra_lcd_priv *priv, int wait)
572 {
573 	if (priv->stage == STAGE_DONE)
574 		return 0;
575 
576 	do {
577 		/* wait if we need to */
578 		debug("%s: stage %d\n", __func__, priv->stage);
579 		if (priv->stage != STAGE_START) {
580 			int delay = priv->timer_next - timer_get_us();
581 
582 			if (delay > 0) {
583 				if (wait)
584 					udelay(delay);
585 				else
586 					return 0;
587 			}
588 		}
589 
590 		if (handle_stage(blob, priv))
591 			return -1;
592 	} while (wait && priv->stage != STAGE_DONE);
593 	if (priv->stage == STAGE_DONE)
594 		debug("%s: LCD init complete\n", __func__);
595 
596 	return 0;
597 }
598 
599 static int tegra_lcd_probe(struct udevice *dev)
600 {
601 	struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
602 	struct video_priv *uc_priv = dev_get_uclass_priv(dev);
603 	struct tegra_lcd_priv *priv = dev_get_priv(dev);
604 	const void *blob = gd->fdt_blob;
605 	int type = DCACHE_OFF;
606 
607 	if (tegra_display_decode_config(blob, dev->of_offset, priv))
608 		return -1;
609 
610 	/* get panel details */
611 	if (fdt_decode_lcd(blob, priv)) {
612 		printf("No valid LCD information in device tree\n");
613 		return -1;
614 	}
615 
616 	/* Initialize the Tegra display controller */
617 	if (tegra_display_probe(blob, priv, (void *)plat->base)) {
618 		printf("%s: Failed to probe display driver\n", __func__);
619 		return -1;
620 	}
621 
622 	tegra_lcd_check_next_stage(blob, priv, 1);
623 
624 	/* Set up the LCD caching as requested */
625 	if (priv->cache_type & FDT_LCD_CACHE_WRITE_THROUGH)
626 		type = DCACHE_WRITETHROUGH;
627 	else if (priv->cache_type & FDT_LCD_CACHE_WRITE_BACK)
628 		type = DCACHE_WRITEBACK;
629 	mmu_set_region_dcache_behaviour(priv->frame_buffer, plat->size, type);
630 
631 	/* Enable flushing after LCD writes if requested */
632 	video_set_flush_dcache(dev, priv->cache_type & FDT_LCD_CACHE_FLUSH);
633 
634 	uc_priv->xsize = priv->width;
635 	uc_priv->ysize = priv->height;
636 	uc_priv->bpix = priv->log2_bpp;
637 	debug("LCD frame buffer at %pa, size %x\n", &priv->frame_buffer,
638 	      plat->size);
639 
640 	return 0;
641 }
642 
643 static int tegra_lcd_bind(struct udevice *dev)
644 {
645 	struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
646 
647 	plat->size = LCD_MAX_WIDTH * LCD_MAX_HEIGHT *
648 		(1 << LCD_MAX_LOG2_BPP) / 8;
649 
650 	return 0;
651 }
652 
653 static const struct video_ops tegra_lcd_ops = {
654 };
655 
656 static const struct udevice_id tegra_lcd_ids[] = {
657 	{ .compatible = "nvidia,tegra20-dc" },
658 	{ }
659 };
660 
661 U_BOOT_DRIVER(tegra_lcd) = {
662 	.name	= "tegra_lcd",
663 	.id	= UCLASS_VIDEO,
664 	.of_match = tegra_lcd_ids,
665 	.ops	= &tegra_lcd_ops,
666 	.bind	= tegra_lcd_bind,
667 	.probe	= tegra_lcd_probe,
668 	.priv_auto_alloc_size	= sizeof(struct tegra_lcd_priv),
669 };
670