U-Boot

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (c) 2015 Google, Inc
 */

#include <common.h>
#include <console.h>
#include <cpu_func.h>
#include <dm.h>
#include <log.h>
#include <malloc.h>
#include <mapmem.h>
#include <stdio_dev.h>
#include <video.h>
#include <video_console.h>
#include <asm/cache.h>
#include <dm/lists.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#ifdef CONFIG_SANDBOX
#include <asm/sdl.h>
#endif

/*
 * Theory of operation:
 *
 * Before relocation each device is bound. The driver for each device must
 * set the @align and @size values in struct video_uc_platdata. This
 * information represents the requires size and alignment of the frame buffer
 * for the device. The values can be an over-estimate but cannot be too
 * small. The actual values will be suppled (in the same manner) by the bind()
 * method after relocation.
 *
 * This information is then picked up by video_reserve() which works out how
 * much memory is needed for all devices. This is allocated between
 * gd->video_bottom and gd->video_top.
 *
 * After relocation the same process occurs. The driver supplies the same
 * @size and @align information and this time video_post_bind() checks that
 * the drivers does not overflow the allocated memory.
 *
 * The frame buffer address is actually set (to plat->base) in
 * video_post_probe(). This function also clears the frame buffer and
 * allocates a suitable text console device. This can then be used to write
 * text to the video device.
 */
DECLARE_GLOBAL_DATA_PTR;

/**
 * struct video_uc_priv - Information for the video uclass
 *
 * @video_ptr: Current allocation position of the video framebuffer pointer.
 *	While binding devices after relocation, this points to the next
 *	available address to use for a device's framebuffer. It starts at
 *	gd->video_top and works downwards, running out of space when it hits
 *	gd->video_bottom.
 */
struct video_uc_priv {
	ulong video_ptr;
};

void video_set_flush_dcache(struct udevice *dev, bool flush)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);

	priv->flush_dcache = flush;
}

static ulong alloc_fb(struct udevice *dev, ulong *addrp)
{
	struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
	ulong base, align, size;

	if (!plat->size)
		return 0;

	align = plat->align ? plat->align : 1 << 20;
	base = *addrp - plat->size;
	base &= ~(align - 1);
	plat->base = base;
	size = *addrp - base;
	*addrp = base;

	return size;
}

int video_reserve(ulong *addrp)
{
	struct udevice *dev;
	ulong size;

	gd->video_top = *addrp;
	for (uclass_find_first_device(UCLASS_VIDEO, &dev);
	     dev;
	     uclass_find_next_device(&dev)) {
		size = alloc_fb(dev, addrp);
		debug("%s: Reserving %lx bytes at %lx for video device '%s'\n",
		      __func__, size, *addrp, dev->name);
	}

	/* Allocate space for PCI video devices in case there were not bound */
	if (*addrp == gd->video_top)
		*addrp -= CONFIG_VIDEO_PCI_DEFAULT_FB_SIZE;

	gd->video_bottom = *addrp;
	gd->fb_base = *addrp;
	debug("Video frame buffers from %lx to %lx\n", gd->video_bottom,
	      gd->video_top);

	return 0;
}

int video_clear(struct udevice *dev)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);
	int ret;

	switch (priv->bpix) {
	case VIDEO_BPP16:
		if (IS_ENABLED(CONFIG_VIDEO_BPP16)) {
			u16 *ppix = priv->fb;
			u16 *end = priv->fb + priv->fb_size;

			while (ppix < end)
				*ppix++ = priv->colour_bg;
			break;
		}
	case VIDEO_BPP32:
		if (IS_ENABLED(CONFIG_VIDEO_BPP32)) {
			u32 *ppix = priv->fb;
			u32 *end = priv->fb + priv->fb_size;

			while (ppix < end)
				*ppix++ = priv->colour_bg;
			break;
		}
	default:
		memset(priv->fb, priv->colour_bg, priv->fb_size);
		break;
	}
	ret = video_sync_copy(dev, priv->fb, priv->fb + priv->fb_size);
	if (ret)
		return ret;

	return 0;
}

void video_set_default_colors(struct udevice *dev, bool invert)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);
	int fore, back;

	if (CONFIG_IS_ENABLED(SYS_WHITE_ON_BLACK)) {
		/* White is used when switching to bold, use light gray here */
		fore = VID_LIGHT_GRAY;
		back = VID_BLACK;
	} else {
		fore = VID_BLACK;
		back = VID_WHITE;
	}
	if (invert) {
		int temp;

		temp = fore;
		fore = back;
		back = temp;
	}
	priv->fg_col_idx = fore;
	priv->bg_col_idx = back;
	priv->colour_fg = vid_console_color(priv, fore);
	priv->colour_bg = vid_console_color(priv, back);
}

/* Flush video activity to the caches */
void video_sync(struct udevice *vid, bool force)
{
	/*
	 * flush_dcache_range() is declared in common.h but it seems that some
	 * architectures do not actually implement it. Is there a way to find
	 * out whether it exists? For now, ARM is safe.
	 */
#if defined(CONFIG_ARM) && !CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
	struct video_priv *priv = dev_get_uclass_priv(vid);

	if (priv->flush_dcache) {
		flush_dcache_range((ulong)priv->fb,
				   ALIGN((ulong)priv->fb + priv->fb_size,
					 CONFIG_SYS_CACHELINE_SIZE));
	}
#elif defined(CONFIG_VIDEO_SANDBOX_SDL)
	struct video_priv *priv = dev_get_uclass_priv(vid);
	static ulong last_sync;

	if (force || get_timer(last_sync) > 10) {
		sandbox_sdl_sync(priv->fb);
		last_sync = get_timer(0);
	}
#endif
}

void video_sync_all(void)
{
	struct udevice *dev;

	for (uclass_find_first_device(UCLASS_VIDEO, &dev);
	     dev;
	     uclass_find_next_device(&dev)) {
		if (device_active(dev))
			video_sync(dev, true);
	}
}

int video_get_xsize(struct udevice *dev)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);

	return priv->xsize;
}

int video_get_ysize(struct udevice *dev)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);

	return priv->ysize;
}

#ifdef CONFIG_VIDEO_COPY
int video_sync_copy(struct udevice *dev, void *from, void *to)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);

	if (priv->copy_fb) {
		long offset, size;

		/* Find the offset of the first byte to copy */
		if ((ulong)to > (ulong)from) {
			size = to - from;
			offset = from - priv->fb;
		} else {
			size = from - to;
			offset = to - priv->fb;
		}

		/*
		 * Allow a bit of leeway for valid requests somewhere near the
		 * frame buffer
		 */
		if (offset < -priv->fb_size || offset > 2 * priv->fb_size) {
#ifdef DEBUG
			char str[80];

			snprintf(str, sizeof(str),
				 "[sync_copy fb=%p, from=%p, to=%p, offset=%lx]",
				 priv->fb, from, to, offset);
			console_puts_select_stderr(true, str);
#endif
			return -EFAULT;
		}

		/*
		 * Silently crop the memcpy. This allows callers to avoid doing
		 * this themselves. It is common for the end pointer to go a
		 * few lines after the end of the frame buffer, since most of
		 * the update algorithms terminate a line after their last write
		 */
		if (offset + size > priv->fb_size) {
			size = priv->fb_size - offset;
		} else if (offset < 0) {
			size += offset;
			offset = 0;
		}

		memcpy(priv->copy_fb + offset, priv->fb + offset, size);
	}

	return 0;
}
#endif

/* Set up the colour map */
static int video_pre_probe(struct udevice *dev)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);

	priv->cmap = calloc(256, sizeof(ushort));
	if (!priv->cmap)
		return -ENOMEM;

	return 0;
}

static int video_pre_remove(struct udevice *dev)
{
	struct video_priv *priv = dev_get_uclass_priv(dev);

	free(priv->cmap);

	return 0;
}

/* Set up the display ready for use */
static int video_post_probe(struct udevice *dev)
{
	struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
	struct video_priv *priv = dev_get_uclass_priv(dev);
	char name[30], drv[15], *str;
	const char *drv_name = drv;
	struct udevice *cons;
	int ret;

	/* Set up the line and display size */
	priv->fb = map_sysmem(plat->base, plat->size);
	if (!priv->line_length)
		priv->line_length = priv->xsize * VNBYTES(priv->bpix);

	priv->fb_size = priv->line_length * priv->ysize;

	if (IS_ENABLED(CONFIG_VIDEO_COPY) && plat->copy_base)
		priv->copy_fb = map_sysmem(plat->copy_base, plat->size);

	/* Set up colors  */
	video_set_default_colors(dev, false);

	if (!CONFIG_IS_ENABLED(NO_FB_CLEAR))
		video_clear(dev);

	/*
	 * Create a text console device. For now we always do this, although
	 * it might be useful to support only bitmap drawing on the device
	 * for boards that don't need to display text. We create a TrueType
	 * console if enabled, a rotated console if the video driver requests
	 * it, otherwise a normal console.
	 *
	 * The console can be override by setting vidconsole_drv_name before
	 * probing this video driver, or in the probe() method.
	 *
	 * TrueType does not support rotation at present so fall back to the
	 * rotated console in that case.
	 */
	if (!priv->rot && IS_ENABLED(CONFIG_CONSOLE_TRUETYPE)) {
		snprintf(name, sizeof(name), "%s.vidconsole_tt", dev->name);
		strcpy(drv, "vidconsole_tt");
	} else {
		snprintf(name, sizeof(name), "%s.vidconsole%d", dev->name,
			 priv->rot);
		snprintf(drv, sizeof(drv), "vidconsole%d", priv->rot);
	}

	str = strdup(name);
	if (!str)
		return -ENOMEM;
	if (priv->vidconsole_drv_name)
		drv_name = priv->vidconsole_drv_name;
	ret = device_bind_driver(dev, drv_name, str, &cons);
	if (ret) {
		debug("%s: Cannot bind console driver\n", __func__);
		return ret;
	}

	ret = device_probe(cons);
	if (ret) {
		debug("%s: Cannot probe console driver\n", __func__);
		return ret;
	}

	return 0;
};

/* Post-relocation, allocate memory for the frame buffer */
static int video_post_bind(struct udevice *dev)
{
	struct video_uc_priv *uc_priv;
	ulong addr;
	ulong size;

	/* Before relocation there is nothing to do here */
	if (!(gd->flags & GD_FLG_RELOC))
		return 0;

	/* Set up the video pointer, if this is the first device */
	uc_priv = dev->uclass->priv;
	if (!uc_priv->video_ptr)
		uc_priv->video_ptr = gd->video_top;

	/* Allocate framebuffer space for this device */
	addr = uc_priv->video_ptr;
	size = alloc_fb(dev, &addr);
	if (addr < gd->video_bottom) {
		/* Device tree node may need the 'u-boot,dm-pre-reloc' or
		 * 'u-boot,dm-pre-proper' tag
		 */
		printf("Video device '%s' cannot allocate frame buffer memory -ensure the device is set up before relocation\n",
		       dev->name);
		return -ENOSPC;
	}
	debug("%s: Claiming %lx bytes at %lx for video device '%s'\n",
	      __func__, size, addr, dev->name);
	uc_priv->video_ptr = addr;

	return 0;
}

UCLASS_DRIVER(video) = {
	.id		= UCLASS_VIDEO,
	.name		= "video",
	.flags		= DM_UC_FLAG_SEQ_ALIAS,
	.post_bind	= video_post_bind,
	.pre_probe	= video_pre_probe,
	.post_probe	= video_post_probe,
	.pre_remove	= video_pre_remove,
	.priv_auto_alloc_size	= sizeof(struct video_uc_priv),
	.per_device_auto_alloc_size	= sizeof(struct video_priv),
	.per_device_platdata_auto_alloc_size = sizeof(struct video_uc_platdata),
};