u-boot/drivers/video/tegra.c

/*
 * Copyright (c) 2011 The Chromium OS Authors.
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <fdtdec.h>
#include <lcd.h>

#include <asm/system.h>
#include <asm/gpio.h>
#include <asm/io.h>

#include <asm/arch/clock.h>
#include <asm/arch/funcmux.h>
#include <asm/arch/pinmux.h>
#include <asm/arch/pwm.h>
#include <asm/arch/display.h>
#include <asm/arch-tegra/timer.h>

DECLARE_GLOBAL_DATA_PTR;

/* These are the stages we go throuh in enabling the LCD */
enum stage_t {
	STAGE_START,
	STAGE_PANEL_VDD,
	STAGE_LVDS,
	STAGE_BACKLIGHT_VDD,
	STAGE_PWM,
	STAGE_BACKLIGHT_EN,
	STAGE_DONE,
};

static enum stage_t stage;	/* Current stage we are at */
static unsigned long timer_next; /* Time we can move onto next stage */

/* Our LCD config, set up in handle_stage() */
static struct fdt_panel_config config;
struct fdt_disp_config *disp_config;	/* Display controller config */
static struct fdt_disp_config dconfig;

enum {
	/* Maximum LCD size we support */
	LCD_MAX_WIDTH		= 1366,
	LCD_MAX_HEIGHT		= 768,
	LCD_MAX_LOG2_BPP	= 4,		/* 2^4 = 16 bpp */
};

vidinfo_t panel_info = {
	/* Insert a value here so that we don't end up in the BSS */
	.vl_col = -1,
};

static void update_window(struct dc_ctlr *dc, struct disp_ctl_win *win)
{
	unsigned h_dda, v_dda;
	unsigned long val;

	val = readl(&dc->cmd.disp_win_header);
	val |= WINDOW_A_SELECT;
	writel(val, &dc->cmd.disp_win_header);

	writel(win->fmt, &dc->win.color_depth);

	clrsetbits_le32(&dc->win.byte_swap, BYTE_SWAP_MASK,
			BYTE_SWAP_NOSWAP << BYTE_SWAP_SHIFT);

	val = win->out_x << H_POSITION_SHIFT;
	val |= win->out_y << V_POSITION_SHIFT;
	writel(val, &dc->win.pos);

	val = win->out_w << H_SIZE_SHIFT;
	val |= win->out_h << V_SIZE_SHIFT;
	writel(val, &dc->win.size);

	val = (win->w * win->bpp / 8) << H_PRESCALED_SIZE_SHIFT;
	val |= win->h << V_PRESCALED_SIZE_SHIFT;
	writel(val, &dc->win.prescaled_size);

	writel(0, &dc->win.h_initial_dda);
	writel(0, &dc->win.v_initial_dda);

	h_dda = (win->w * 0x1000) / max(win->out_w - 1, 1U);
	v_dda = (win->h * 0x1000) / max(win->out_h - 1, 1U);

	val = h_dda << H_DDA_INC_SHIFT;
	val |= v_dda << V_DDA_INC_SHIFT;
	writel(val, &dc->win.dda_increment);

	writel(win->stride, &dc->win.line_stride);
	writel(0, &dc->win.buf_stride);

	val = WIN_ENABLE;
	if (win->bpp < 24)
		val |= COLOR_EXPAND;
	writel(val, &dc->win.win_opt);

	writel((unsigned long)win->phys_addr, &dc->winbuf.start_addr);
	writel(win->x, &dc->winbuf.addr_h_offset);
	writel(win->y, &dc->winbuf.addr_v_offset);

	writel(0xff00, &dc->win.blend_nokey);
	writel(0xff00, &dc->win.blend_1win);

	val = GENERAL_ACT_REQ | WIN_A_ACT_REQ;
	val |= GENERAL_UPDATE | WIN_A_UPDATE;
	writel(val, &dc->cmd.state_ctrl);
}

static void write_pair(struct fdt_disp_config *config, int item, u32 *reg)
{
	writel(config->horiz_timing[item] |
			(config->vert_timing[item] << 16), reg);
}

static int update_display_mode(struct dc_disp_reg *disp,
		struct fdt_disp_config *config)
{
	unsigned long val;
	unsigned long rate;
	unsigned long div;

	writel(0x0, &disp->disp_timing_opt);
	write_pair(config, FDT_LCD_TIMING_REF_TO_SYNC, &disp->ref_to_sync);
	write_pair(config, FDT_LCD_TIMING_SYNC_WIDTH, &disp->sync_width);
	write_pair(config, FDT_LCD_TIMING_BACK_PORCH, &disp->back_porch);
	write_pair(config, FDT_LCD_TIMING_FRONT_PORCH, &disp->front_porch);

	writel(config->width | (config->height << 16), &disp->disp_active);

	val = DE_SELECT_ACTIVE << DE_SELECT_SHIFT;
	val |= DE_CONTROL_NORMAL << DE_CONTROL_SHIFT;
	writel(val, &disp->data_enable_opt);

	val = DATA_FORMAT_DF1P1C << DATA_FORMAT_SHIFT;
	val |= DATA_ALIGNMENT_MSB << DATA_ALIGNMENT_SHIFT;
	val |= DATA_ORDER_RED_BLUE << DATA_ORDER_SHIFT;
	writel(val, &disp->disp_interface_ctrl);

	/*
	 * The pixel clock divider is in 7.1 format (where the bottom bit
	 * represents 0.5). Here we calculate the divider needed to get from
	 * the display clock (typically 600MHz) to the pixel clock. We round
	 * up or down as requried.
	 */
	rate = clock_get_periph_rate(PERIPH_ID_DISP1, CLOCK_ID_CGENERAL);
	div = ((rate * 2 + config->pixel_clock / 2) / config->pixel_clock) - 2;
	debug("Display clock %lu, divider %lu\n", rate, div);

	writel(0x00010001, &disp->shift_clk_opt);

	val = PIXEL_CLK_DIVIDER_PCD1 << PIXEL_CLK_DIVIDER_SHIFT;
	val |= div << SHIFT_CLK_DIVIDER_SHIFT;
	writel(val, &disp->disp_clk_ctrl);

	return 0;
}

/* Start up the display and turn on power to PWMs */
static void basic_init(struct dc_cmd_reg *cmd)
{
	u32 val;

	writel(0x00000100, &cmd->gen_incr_syncpt_ctrl);
	writel(0x0000011a, &cmd->cont_syncpt_vsync);
	writel(0x00000000, &cmd->int_type);
	writel(0x00000000, &cmd->int_polarity);
	writel(0x00000000, &cmd->int_mask);
	writel(0x00000000, &cmd->int_enb);

	val = PW0_ENABLE | PW1_ENABLE | PW2_ENABLE;
	val |= PW3_ENABLE | PW4_ENABLE | PM0_ENABLE;
	val |= PM1_ENABLE;
	writel(val, &cmd->disp_pow_ctrl);

	val = readl(&cmd->disp_cmd);
	val |= CTRL_MODE_C_DISPLAY << CTRL_MODE_SHIFT;
	writel(val, &cmd->disp_cmd);
}

static void basic_init_timer(struct dc_disp_reg *disp)
{
	writel(0x00000020, &disp->mem_high_pri);
	writel(0x00000001, &disp->mem_high_pri_timer);
}

static const u32 rgb_enb_tab[PIN_REG_COUNT] = {
	0x00000000,
	0x00000000,
	0x00000000,
	0x00000000,
};

static const u32 rgb_polarity_tab[PIN_REG_COUNT] = {
	0x00000000,
	0x01000000,
	0x00000000,
	0x00000000,
};

static const u32 rgb_data_tab[PIN_REG_COUNT] = {
	0x00000000,
	0x00000000,
	0x00000000,
	0x00000000,
};

static const u32 rgb_sel_tab[PIN_OUTPUT_SEL_COUNT] = {
	0x00000000,
	0x00000000,
	0x00000000,
	0x00000000,
	0x00210222,
	0x00002200,
	0x00020000,
};

static void rgb_enable(struct dc_com_reg *com)
{
	int i;

	for (i = 0; i < PIN_REG_COUNT; i++) {
		writel(rgb_enb_tab[i], &com->pin_output_enb[i]);
		writel(rgb_polarity_tab[i], &com->pin_output_polarity[i]);
		writel(rgb_data_tab[i], &com->pin_output_data[i]);
	}

	for (i = 0; i < PIN_OUTPUT_SEL_COUNT; i++)
		writel(rgb_sel_tab[i], &com->pin_output_sel[i]);
}

static int setup_window(struct disp_ctl_win *win,
			struct fdt_disp_config *config)
{
	win->x = 0;
	win->y = 0;
	win->w = config->width;
	win->h = config->height;
	win->out_x = 0;
	win->out_y = 0;
	win->out_w = config->width;
	win->out_h = config->height;
	win->phys_addr = config->frame_buffer;
	win->stride = config->width * (1 << config->log2_bpp) / 8;
	debug("%s: depth = %d\n", __func__, config->log2_bpp);
	switch (config->log2_bpp) {
	case 5:
	case 24:
		win->fmt = COLOR_DEPTH_R8G8B8A8;
		win->bpp = 32;
		break;
	case 4:
		win->fmt = COLOR_DEPTH_B5G6R5;
		win->bpp = 16;
		break;

	default:
		debug("Unsupported LCD bit depth");
		return -1;
	}

	return 0;
}

/**
 * Return the current display configuration
 *
 * @return pointer to display configuration, or NULL if there is no valid
 * config
 */
struct fdt_disp_config *tegra_display_get_config(void)
{
	return dconfig.valid ? &dconfig : NULL;
}

static void debug_timing(const char *name, unsigned int timing[])
{
#ifdef DEBUG
	int i;

	debug("%s timing: ", name);
	for (i = 0; i < FDT_LCD_TIMING_COUNT; i++)
		debug("%d ", timing[i]);
	debug("\n");
#endif
}

/**
 * Decode panel information from the fdt, according to a standard binding
 *
 * @param blob		fdt blob
 * @param node		offset of fdt node to read from
 * @param config	structure to store fdt config into
 * @return 0 if ok, -ve on error
 */
static int tegra_decode_panel(const void *blob, int node,
			      struct fdt_disp_config *config)
{
	int front, back, ref;

	config->width = fdtdec_get_int(blob, node, "xres", -1);
	config->height = fdtdec_get_int(blob, node, "yres", -1);
	config->pixel_clock = fdtdec_get_int(blob, node, "clock", 0);
	if (!config->pixel_clock || config->width == -1 ||
	    config->height == -1) {
		debug("%s: Pixel parameters missing\n", __func__);
		return -FDT_ERR_NOTFOUND;
	}

	back = fdtdec_get_int(blob, node, "left-margin", -1);
	front = fdtdec_get_int(blob, node, "right-margin", -1);
	ref = fdtdec_get_int(blob, node, "hsync-len", -1);
	if ((back | front | ref) == -1) {
		debug("%s: Horizontal parameters missing\n", __func__);
		return -FDT_ERR_NOTFOUND;
	}

	/* Use a ref-to-sync of 1 always, and take this from the front porch */
	config->horiz_timing[FDT_LCD_TIMING_REF_TO_SYNC] = 1;
	config->horiz_timing[FDT_LCD_TIMING_SYNC_WIDTH] = ref;
	config->horiz_timing[FDT_LCD_TIMING_BACK_PORCH] = back;
	config->horiz_timing[FDT_LCD_TIMING_FRONT_PORCH] = front -
		config->horiz_timing[FDT_LCD_TIMING_REF_TO_SYNC];
	debug_timing("horiz", config->horiz_timing);

	back = fdtdec_get_int(blob, node, "upper-margin", -1);
	front = fdtdec_get_int(blob, node, "lower-margin", -1);
	ref = fdtdec_get_int(blob, node, "vsync-len", -1);
	if ((back | front | ref) == -1) {
		debug("%s: Vertical parameters missing\n", __func__);
		return -FDT_ERR_NOTFOUND;
	}

	config->vert_timing[FDT_LCD_TIMING_REF_TO_SYNC] = 1;
	config->vert_timing[FDT_LCD_TIMING_SYNC_WIDTH] = ref;
	config->vert_timing[FDT_LCD_TIMING_BACK_PORCH] = back;
	config->vert_timing[FDT_LCD_TIMING_FRONT_PORCH] = front -
		config->vert_timing[FDT_LCD_TIMING_REF_TO_SYNC];
	debug_timing("vert", config->vert_timing);

	return 0;
}

/**
 * Decode the display controller information from the fdt.
 *
 * @param blob		fdt blob
 * @param config	structure to store fdt config into
 * @return 0 if ok, -ve on error
 */
static int tegra_display_decode_config(const void *blob,
				       struct fdt_disp_config *config)
{
	int node, rgb;
	int bpp, bit;

	/* TODO: Support multiple controllers */
	node = fdtdec_next_compatible(blob, 0, COMPAT_NVIDIA_TEGRA20_DC);
	if (node < 0) {
		debug("%s: Cannot find display controller node in fdt\n",
		      __func__);
		return node;
	}
	config->disp = (struct disp_ctlr *)fdtdec_get_addr(blob, node, "reg");
	if (!config->disp) {
		debug("%s: No display controller address\n", __func__);
		return -1;
	}

	rgb = fdt_subnode_offset(blob, node, "rgb");

	config->panel_node = fdtdec_lookup_phandle(blob, rgb, "nvidia,panel");
	if (config->panel_node < 0) {
		debug("%s: Cannot find panel information\n", __func__);
		return -1;
	}

	if (tegra_decode_panel(blob, config->panel_node, config)) {
		debug("%s: Failed to decode panel information\n", __func__);
		return -1;
	}

	bpp = fdtdec_get_int(blob, config->panel_node, "nvidia,bits-per-pixel",
			     -1);
	bit = ffs(bpp) - 1;
	if (bpp == (1 << bit))
		config->log2_bpp = bit;
	else
		config->log2_bpp = bpp;
	if (bpp == -1) {
		debug("%s: Pixel bpp parameters missing\n", __func__);
		return -FDT_ERR_NOTFOUND;
	}
	config->bpp = bpp;

	config->valid = 1;	/* we have a valid configuration */

	return 0;
}

/**
 * Register a new display based on device tree configuration.
 *
 * The frame buffer can be positioned by U-Boot or overriden by the fdt.
 * You should pass in the U-Boot address here, and check the contents of
 * struct fdt_disp_config to see what was actually chosen.
 *
 * @param blob			Device tree blob
 * @param default_lcd_base	Default address of LCD frame buffer
 * @return 0 if ok, -1 on error (unsupported bits per pixel)
 */
static int tegra_display_probe(const void *blob, void *default_lcd_base)
{
	struct disp_ctl_win window;
	struct dc_ctlr *dc;

	if (tegra_display_decode_config(blob, &dconfig))
		return -1;

	dconfig.frame_buffer = (u32)default_lcd_base;

	dc = (struct dc_ctlr *)dconfig.disp;

	/*
	 * A header file for clock constants was NAKed upstream.
	 * TODO: Put this into the FDT and fdt_lcd struct when we have clock
	 * support there
	 */
	clock_start_periph_pll(PERIPH_ID_HOST1X, CLOCK_ID_PERIPH,
			       144 * 1000000);
	clock_start_periph_pll(PERIPH_ID_DISP1, CLOCK_ID_CGENERAL,
			       600 * 1000000);
	basic_init(&dc->cmd);
	basic_init_timer(&dc->disp);
	rgb_enable(&dc->com);

	if (dconfig.pixel_clock)
		update_display_mode(&dc->disp, &dconfig);

	if (setup_window(&window, &dconfig))
		return -1;

	update_window(dc, &window);

	return 0;
}

static void update_panel_size(struct fdt_disp_config *config)
{
	panel_info.vl_col = config->width;
	panel_info.vl_row = config->height;
	panel_info.vl_bpix = config->log2_bpp;
}

/*
 *  Main init function called by lcd driver.
 *  Inits and then prints test pattern if required.
 */

void lcd_ctrl_init(void *lcdbase)
{
	int type = DCACHE_OFF;
	int size;

	assert(disp_config);

	/* Make sure that we can acommodate the selected LCD */
	assert(disp_config->width <= LCD_MAX_WIDTH);
	assert(disp_config->height <= LCD_MAX_HEIGHT);
	assert(disp_config->log2_bpp <= LCD_MAX_LOG2_BPP);
	if (disp_config->width <= LCD_MAX_WIDTH
			&& disp_config->height <= LCD_MAX_HEIGHT
			&& disp_config->log2_bpp <= LCD_MAX_LOG2_BPP)
		update_panel_size(disp_config);
	size = lcd_get_size(&lcd_line_length);

	/* Set up the LCD caching as requested */
	if (config.cache_type & FDT_LCD_CACHE_WRITE_THROUGH)
		type = DCACHE_WRITETHROUGH;
	else if (config.cache_type & FDT_LCD_CACHE_WRITE_BACK)
		type = DCACHE_WRITEBACK;
	mmu_set_region_dcache_behaviour(disp_config->frame_buffer, size, type);

	/* Enable flushing after LCD writes if requested */
	lcd_set_flush_dcache(config.cache_type & FDT_LCD_CACHE_FLUSH);

	debug("LCD frame buffer at %pa\n", &disp_config->frame_buffer);
}

ulong calc_fbsize(void)
{
	return (panel_info.vl_col * panel_info.vl_row *
		NBITS(panel_info.vl_bpix)) / 8;
}

void lcd_setcolreg(ushort regno, ushort red, ushort green, ushort blue)
{
}

void tegra_lcd_early_init(const void *blob)
{
	/*
	 * Go with the maximum size for now. We will fix this up after
	 * relocation. These values are only used for memory alocation.
	 */
	panel_info.vl_col = LCD_MAX_WIDTH;
	panel_info.vl_row = LCD_MAX_HEIGHT;
	panel_info.vl_bpix = LCD_MAX_LOG2_BPP;
}

/**
 * Decode the panel information from the fdt.
 *
 * @param blob		fdt blob
 * @param config	structure to store fdt config into
 * @return 0 if ok, -ve on error
 */
static int fdt_decode_lcd(const void *blob, struct fdt_panel_config *config)
{
	int display_node;

	disp_config = tegra_display_get_config();
	if (!disp_config) {
		debug("%s: Display controller is not configured\n", __func__);
		return -1;
	}
	display_node = disp_config->panel_node;
	if (display_node < 0) {
		debug("%s: No panel configuration available\n", __func__);
		return -1;
	}

	config->pwm_channel = pwm_request(blob, display_node, "nvidia,pwm");
	if (config->pwm_channel < 0) {
		debug("%s: Unable to request PWM channel\n", __func__);
		return -1;
	}

	config->cache_type = fdtdec_get_int(blob, display_node,
					    "nvidia,cache-type",
					    FDT_LCD_CACHE_WRITE_BACK_FLUSH);

	/* These GPIOs are all optional */
	gpio_request_by_name_nodev(blob, display_node,
				   "nvidia,backlight-enable-gpios", 0,
				   &config->backlight_en, GPIOD_IS_OUT);
	gpio_request_by_name_nodev(blob, display_node,
				   "nvidia,lvds-shutdown-gpios", 0,
				   &config->lvds_shutdown, GPIOD_IS_OUT);
	gpio_request_by_name_nodev(blob, display_node,
				   "nvidia,backlight-vdd-gpios", 0,
				   &config->backlight_vdd, GPIOD_IS_OUT);
	gpio_request_by_name_nodev(blob, display_node,
				   "nvidia,panel-vdd-gpios", 0,
				   &config->panel_vdd, GPIOD_IS_OUT);

	return fdtdec_get_int_array(blob, display_node, "nvidia,panel-timings",
			config->panel_timings, FDT_LCD_TIMINGS);
}

/**
 * Handle the next stage of device init
 */
static int handle_stage(const void *blob)
{
	debug("%s: stage %d\n", __func__, stage);

	/* do the things for this stage */
	switch (stage) {
	case STAGE_START:
		/* Initialize the Tegra display controller */
		if (tegra_display_probe(gd->fdt_blob, (void *)gd->fb_base)) {
			printf("%s: Failed to probe display driver\n",
			__func__);
			return -1;
		}

		/* get panel details */
		if (fdt_decode_lcd(blob, &config)) {
			printf("No valid LCD information in device tree\n");
			return -1;
		}

		/*
		 * It is possible that the FDT has requested that the LCD be
		 * disabled. We currently don't support this. It would require
		 * changes to U-Boot LCD subsystem to have LCD support
		 * compiled in but not used. An easier option might be to
		 * still have a frame buffer, but leave the backlight off and
		 * remove all mention of lcd in the stdout environment
		 * variable.
		 */

		funcmux_select(PERIPH_ID_DISP1, FUNCMUX_DEFAULT);
		break;
	case STAGE_PANEL_VDD:
		if (dm_gpio_is_valid(&config.panel_vdd))
			dm_gpio_set_value(&config.panel_vdd, 1);
		break;
	case STAGE_LVDS:
		if (dm_gpio_is_valid(&config.lvds_shutdown))
			dm_gpio_set_value(&config.lvds_shutdown, 1);
		break;
	case STAGE_BACKLIGHT_VDD:
		if (dm_gpio_is_valid(&config.backlight_vdd))
			dm_gpio_set_value(&config.backlight_vdd, 1);
		break;
	case STAGE_PWM:
		/* Enable PWM at 15/16 high, 32768 Hz with divider 1 */
		pinmux_set_func(PMUX_PINGRP_GPU, PMUX_FUNC_PWM);
		pinmux_tristate_disable(PMUX_PINGRP_GPU);

		pwm_enable(config.pwm_channel, 32768, 0xdf, 1);
		break;
	case STAGE_BACKLIGHT_EN:
		if (dm_gpio_is_valid(&config.backlight_en))
			dm_gpio_set_value(&config.backlight_en, 1);
		break;
	case STAGE_DONE:
		break;
	}

	/* set up timer for next stage */
	timer_next = timer_get_us();
	if (stage < FDT_LCD_TIMINGS)
		timer_next += config.panel_timings[stage] * 1000;

	/* move to next stage */
	stage++;
	return 0;
}

int tegra_lcd_check_next_stage(const void *blob, int wait)
{
	if (stage == STAGE_DONE)
		return 0;

	do {
		/* wait if we need to */
		debug("%s: stage %d\n", __func__, stage);
		if (stage != STAGE_START) {
			int delay = timer_next - timer_get_us();

			if (delay > 0) {
				if (wait)
					udelay(delay);
				else
					return 0;
			}
		}

		if (handle_stage(blob))
			return -1;
	} while (wait && stage != STAGE_DONE);
	if (stage == STAGE_DONE)
		debug("%s: LCD init complete\n", __func__);

	return 0;
}

void lcd_enable(void)
{
	/*
	 * Backlight and power init will be done separately in
	 * tegra_lcd_check_next_stage(), which should be called in
	 * board_late_init().
	 *
	 * U-Boot code supports only colour depth, selected at compile time.
	 * The device tree setting should match this. Otherwise the display
	 * will not look right, and U-Boot may crash.
	 */
	if (disp_config->log2_bpp != LCD_BPP) {
		printf("%s: Error: LCD depth configured in FDT (%d = %dbpp)"
			" must match setting of LCD_BPP (%d)\n", __func__,
		       disp_config->log2_bpp, disp_config->bpp, LCD_BPP);
	}
}