xref: /aosp_15_r20/external/libdrm/tests/util/pattern.c (revision 7688df22e49036ff52a766b7101da3a49edadb8c)

/*
 * Copyright 2008 Tungsten Graphics
 *   Jakob Bornecrantz <[email protected]>
 * Copyright 2008 Intel Corporation
 *   Jesse Barnes <[email protected]>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <drm_fourcc.h>

#if HAVE_CAIRO
#include <cairo.h>
#include <math.h>
#endif

#include "common.h"
#include "format.h"
#include "pattern.h"

struct color_rgb24 {
	unsigned int value:24;
} __attribute__((__packed__));

struct color_yuv {
	unsigned char y;
	unsigned char u;
	unsigned char v;
};

#define MAKE_YUV_601_Y(r, g, b) \
	((( 66 * (r) + 129 * (g) +  25 * (b) + 128) >> 8) + 16)
#define MAKE_YUV_601_U(r, g, b) \
	(((-38 * (r) -  74 * (g) + 112 * (b) + 128) >> 8) + 128)
#define MAKE_YUV_601_V(r, g, b) \
	(((112 * (r) -  94 * (g) -  18 * (b) + 128) >> 8) + 128)

#define MAKE_YUV_601(r, g, b) \
	{ .y = MAKE_YUV_601_Y(r, g, b), \
	  .u = MAKE_YUV_601_U(r, g, b), \
	  .v = MAKE_YUV_601_V(r, g, b) }

static inline uint16_t swap16(uint16_t x)
{
	return ((x & 0x00ffU) << 8) | ((x & 0xff00U) >> 8);
}

static inline uint32_t swap32(uint32_t x)
{
	return ((x & 0x000000ffU) << 24) |
	       ((x & 0x0000ff00U) <<  8) |
	       ((x & 0x00ff0000U) >>  8) |
	       ((x & 0xff000000U) >> 24);
}

#ifdef HAVE_BIG_ENDIAN
#define cpu_to_be16(x)			(x)
#define cpu_to_le16(x)			swap16(x)
#define cpu_to_le32(x)			swap32(x)
#define fb_foreign_endian(format)	(!((format) & DRM_FORMAT_BIG_ENDIAN))
#else
#define cpu_to_be16(x)			swap16(x)
#define cpu_to_le16(x)			(x)
#define cpu_to_le32(x)			(x)
#define fb_foreign_endian(format)	((format) & DRM_FORMAT_BIG_ENDIAN)
#endif

#define cpu_to_fb16(x)	(fb_be ? cpu_to_be16(x) : cpu_to_le16(x))

/* This function takes 8-bit color values */
static inline uint32_t shiftcolor8(const struct util_color_component *comp,
				  uint32_t value)
{
	value &= 0xff;
	/* Fill the low bits with the high bits. */
	value = (value << 8) | value;
	/* Shift down to remove unwanted low bits */
	value = value >> (16 - comp->length);
	/* Shift back up to where the value should be */
	return value << comp->offset;
}

/* This function takes 10-bit color values */
static inline uint32_t shiftcolor10(const struct util_color_component *comp,
				    uint32_t value)
{
	value &= 0x3ff;
	/* Fill the low bits with the high bits. */
	value = (value << 6) | (value >> 4);
	/* Shift down to remove unwanted low bits */
	value = value >> (16 - comp->length);
	/* Shift back up to where the value should be */
	return value << comp->offset;
}

/* This function takes 16-bit color values */
static inline uint64_t shiftcolor16(const struct util_color_component *comp,
				    uint64_t value)
{
	value &= 0xffff;
	/* Shift down to remove unwanted low bits */
	value = value >> (16 - comp->length);
	/* Shift back up to where the value should be */
	return value << comp->offset;
}

#define MAKE_RGBA10(rgb, r, g, b, a) \
	(shiftcolor10(&(rgb)->red, (r)) | \
	 shiftcolor10(&(rgb)->green, (g)) | \
	 shiftcolor10(&(rgb)->blue, (b)) | \
	 shiftcolor10(&(rgb)->alpha, (a)))

#define MAKE_RGBA(rgb, r, g, b, a) \
	(shiftcolor8(&(rgb)->red, (r)) | \
	 shiftcolor8(&(rgb)->green, (g)) | \
	 shiftcolor8(&(rgb)->blue, (b)) | \
	 shiftcolor8(&(rgb)->alpha, (a)))

#define MAKE_RGB24(rgb, r, g, b) \
	{ .value = MAKE_RGBA(rgb, r, g, b, 0) }


/**
  * Takes a uint16_t, divides by 65536, converts the infinite-precision
  * result to fp16 with round-to-zero.
  *
  * Copied from mesa:src/util/half_float.c
  */
static uint16_t uint16_div_64k_to_half(uint16_t v)
{
	/* Zero or subnormal. Set the mantissa to (v << 8) and return. */
	if (v < 4)
		return v << 8;

	/* Count the leading 0s in the uint16_t */
	int n = __builtin_clz(v) - 16;

	/* Shift the mantissa up so bit 16 is the hidden 1 bit,
	 * mask it off, then shift back down to 10 bits
	 */
	int m = ( ((uint32_t)v << (n + 1)) & 0xffff ) >> 6;

	/*  (0{n} 1 X{15-n}) * 2^-16
	 * = 1.X * 2^(15-n-16)
	 * = 1.X * 2^(14-n - 15)
	 * which is the FP16 form with e = 14 - n
	 */
	int e = 14 - n;

	return (e << 10) | m;
}

#define MAKE_RGBA8FP16(rgb, r, g, b, a) \
	(shiftcolor16(&(rgb)->red, uint16_div_64k_to_half((r) << 8)) | \
	 shiftcolor16(&(rgb)->green, uint16_div_64k_to_half((g) << 8)) | \
	 shiftcolor16(&(rgb)->blue, uint16_div_64k_to_half((b) << 8)) | \
	 shiftcolor16(&(rgb)->alpha, uint16_div_64k_to_half((a) << 8)))

#define MAKE_RGBA10FP16(rgb, r, g, b, a) \
	(shiftcolor16(&(rgb)->red, uint16_div_64k_to_half((r) << 6)) | \
	 shiftcolor16(&(rgb)->green, uint16_div_64k_to_half((g) << 6)) | \
	 shiftcolor16(&(rgb)->blue, uint16_div_64k_to_half((b) << 6)) | \
	 shiftcolor16(&(rgb)->alpha, uint16_div_64k_to_half((a) << 6)))

static void fill_smpte_yuv_planar(const struct util_yuv_info *yuv,
				  unsigned char *y_mem, unsigned char *u_mem,
				  unsigned char *v_mem, unsigned int width,
				  unsigned int height, unsigned int stride)
{
	const struct color_yuv colors_top[] = {
		MAKE_YUV_601(192, 192, 192),	/* grey */
		MAKE_YUV_601(192, 192, 0),	/* yellow */
		MAKE_YUV_601(0, 192, 192),	/* cyan */
		MAKE_YUV_601(0, 192, 0),	/* green */
		MAKE_YUV_601(192, 0, 192),	/* magenta */
		MAKE_YUV_601(192, 0, 0),	/* red */
		MAKE_YUV_601(0, 0, 192),	/* blue */
	};
	const struct color_yuv colors_middle[] = {
		MAKE_YUV_601(0, 0, 192),	/* blue */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(192, 0, 192),	/* magenta */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(0, 192, 192),	/* cyan */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(192, 192, 192),	/* grey */
	};
	const struct color_yuv colors_bottom[] = {
		MAKE_YUV_601(0, 33, 76),	/* in-phase */
		MAKE_YUV_601(255, 255, 255),	/* super white */
		MAKE_YUV_601(50, 0, 106),	/* quadrature */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(9, 9, 9),		/* 3.5% */
		MAKE_YUV_601(19, 19, 19),	/* 7.5% */
		MAKE_YUV_601(29, 29, 29),	/* 11.5% */
		MAKE_YUV_601(19, 19, 19),	/* black */
	};
	unsigned int cs = yuv->chroma_stride;
	unsigned int xsub = yuv->xsub;
	unsigned int ysub = yuv->ysub;
	unsigned int x;
	unsigned int y;

	/* Luma */
	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			y_mem[x] = colors_top[x * 7 / width].y;
		y_mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			y_mem[x] = colors_middle[x * 7 / width].y;
		y_mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			y_mem[x] = colors_bottom[x * 4 / (width * 5 / 7)].y;
		for (; x < width * 6 / 7; ++x)
			y_mem[x] = colors_bottom[(x - width * 5 / 7) * 3
						 / (width / 7) + 4].y;
		for (; x < width; ++x)
			y_mem[x] = colors_bottom[7].y;
		y_mem += stride;
	}

	/* Chroma */
	for (y = 0; y < height / ysub * 6 / 9; ++y) {
		for (x = 0; x < width; x += xsub) {
			u_mem[x*cs/xsub] = colors_top[x * 7 / width].u;
			v_mem[x*cs/xsub] = colors_top[x * 7 / width].v;
		}
		u_mem += stride * cs / xsub;
		v_mem += stride * cs / xsub;
	}

	for (; y < height / ysub * 7 / 9; ++y) {
		for (x = 0; x < width; x += xsub) {
			u_mem[x*cs/xsub] = colors_middle[x * 7 / width].u;
			v_mem[x*cs/xsub] = colors_middle[x * 7 / width].v;
		}
		u_mem += stride * cs / xsub;
		v_mem += stride * cs / xsub;
	}

	for (; y < height / ysub; ++y) {
		for (x = 0; x < width * 5 / 7; x += xsub) {
			u_mem[x*cs/xsub] =
				colors_bottom[x * 4 / (width * 5 / 7)].u;
			v_mem[x*cs/xsub] =
				colors_bottom[x * 4 / (width * 5 / 7)].v;
		}
		for (; x < width * 6 / 7; x += xsub) {
			u_mem[x*cs/xsub] = colors_bottom[(x - width * 5 / 7) *
							 3 / (width / 7) + 4].u;
			v_mem[x*cs/xsub] = colors_bottom[(x - width * 5 / 7) *
							 3 / (width / 7) + 4].v;
		}
		for (; x < width; x += xsub) {
			u_mem[x*cs/xsub] = colors_bottom[7].u;
			v_mem[x*cs/xsub] = colors_bottom[7].v;
		}
		u_mem += stride * cs / xsub;
		v_mem += stride * cs / xsub;
	}
}

static void write_pixels_10bpp(unsigned char *mem,
			       unsigned short a,
			       unsigned short b,
			       unsigned short c,
			       unsigned short d)
{
	  mem[0] = (a & 0xff);
	  mem[1] = ((a >> 8) & 0x3) | ((b & 0x3f) << 2);
	  mem[2] = ((b >> 6) & 0xf) | ((c & 0xf) << 4);
	  mem[3] = ((c >> 4) & 0x3f) | ((d & 0x3) << 6);
	  mem[4] = ((d >> 2) & 0xff);
}

static void fill_smpte_yuv_planar_10bpp(const struct util_yuv_info *yuv,
					unsigned char *y_mem,
					unsigned char *uv_mem,
					unsigned int width,
					unsigned int height,
					unsigned int stride)
{
	const struct color_yuv colors_top[] = {
		MAKE_YUV_601(192, 192, 192),	/* grey */
		MAKE_YUV_601(192, 192, 0),	/* yellow */
		MAKE_YUV_601(0, 192, 192),	/* cyan */
		MAKE_YUV_601(0, 192, 0),	/* green */
		MAKE_YUV_601(192, 0, 192),	/* magenta */
		MAKE_YUV_601(192, 0, 0),	/* red */
		MAKE_YUV_601(0, 0, 192),	/* blue */
	};
	const struct color_yuv colors_middle[] = {
		MAKE_YUV_601(0, 0, 192),	/* blue */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(192, 0, 192),	/* magenta */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(0, 192, 192),	/* cyan */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(192, 192, 192),	/* grey */
	};
	const struct color_yuv colors_bottom[] = {
		MAKE_YUV_601(0, 33, 76),	/* in-phase */
		MAKE_YUV_601(255, 255, 255),	/* super white */
		MAKE_YUV_601(50, 0, 106),	/* quadrature */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(9, 9, 9),		/* 3.5% */
		MAKE_YUV_601(19, 19, 19),	/* 7.5% */
		MAKE_YUV_601(29, 29, 29),	/* 11.5% */
		MAKE_YUV_601(19, 19, 19),	/* black */
	};
	unsigned int cs = yuv->chroma_stride;
	unsigned int xsub = yuv->xsub;
	unsigned int ysub = yuv->ysub;
	unsigned int xstep = cs * xsub;
	unsigned int x;
	unsigned int y;

	/* Luma */
	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; x += 4)
			write_pixels_10bpp(&y_mem[(x * 5) / 4],
				colors_top[(x+0) * 7 / width].y << 2,
				colors_top[(x+1) * 7 / width].y << 2,
				colors_top[(x+2) * 7 / width].y << 2,
				colors_top[(x+3) * 7 / width].y << 2);
		y_mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; x += 4)
			write_pixels_10bpp(&y_mem[(x * 5) / 4],
				colors_middle[(x+0) * 7 / width].y << 2,
				colors_middle[(x+1) * 7 / width].y << 2,
				colors_middle[(x+2) * 7 / width].y << 2,
				colors_middle[(x+3) * 7 / width].y << 2);
		y_mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; x += 4)
			write_pixels_10bpp(&y_mem[(x * 5) / 4],
				colors_bottom[(x+0) * 4 / (width * 5 / 7)].y << 2,
				colors_bottom[(x+1) * 4 / (width * 5 / 7)].y << 2,
				colors_bottom[(x+2) * 4 / (width * 5 / 7)].y << 2,
				colors_bottom[(x+3) * 4 / (width * 5 / 7)].y << 2);
		for (; x < width * 6 / 7; x += 4)
			write_pixels_10bpp(&y_mem[(x * 5) / 4],
				colors_bottom[((x+0) - width * 5 / 7) * 3 / (width / 7) + 4].y << 2,
				colors_bottom[((x+1) - width * 5 / 7) * 3 / (width / 7) + 4].y << 2,
				colors_bottom[((x+2) - width * 5 / 7) * 3 / (width / 7) + 4].y << 2,
				colors_bottom[((x+3) - width * 5 / 7) * 3 / (width / 7) + 4].y << 2);
		for (; x < width; x += 4)
			write_pixels_10bpp(&y_mem[(x * 5) / 4],
				colors_bottom[7].y << 2,
				colors_bottom[7].y << 2,
				colors_bottom[7].y << 2,
				colors_bottom[7].y << 2);
		y_mem += stride;
	}

	/* Chroma */
	for (y = 0; y < height * 6 / 9; y += ysub) {
		for (x = 0; x < width; x += xstep)
			write_pixels_10bpp(&uv_mem[(x * 5) / xstep],
				colors_top[(x+0) * 7 / width].u << 2,
				colors_top[(x+0) * 7 / width].v << 2,
				colors_top[(x+xsub) * 7 / width].u << 2,
				colors_top[(x+xsub) * 7 / width].v << 2);
		uv_mem += stride * cs / xsub;
	}

	for (; y < height * 7 / 9; y += ysub) {
		for (x = 0; x < width; x += xstep)
			write_pixels_10bpp(&uv_mem[(x * 5) / xstep],
				colors_middle[(x+0) * 7 / width].u << 2,
				colors_middle[(x+0) * 7 / width].v << 2,
				colors_middle[(x+xsub) * 7 / width].u << 2,
				colors_middle[(x+xsub) * 7 / width].v << 2);
		uv_mem += stride * cs / xsub;
	}

	for (; y < height; y += ysub) {
		for (x = 0; x < width * 5 / 7; x += xstep)
			write_pixels_10bpp(&uv_mem[(x * 5) / xstep],
				colors_bottom[(x+0) * 4 / (width * 5 / 7)].u << 2,
				colors_bottom[(x+0) * 4 / (width * 5 / 7)].v << 2,
				colors_bottom[(x+xsub) * 4 / (width * 5 / 7)].u << 2,
				colors_bottom[(x+xsub) * 4 / (width * 5 / 7)].v << 2);
		for (; x < width * 6 / 7; x += xstep)
			write_pixels_10bpp(&uv_mem[(x * 5) / xstep],
				colors_bottom[((x+0) - width * 5 / 7) * 3 / (width / 7) + 4].u << 2,
				colors_bottom[((x+0) - width * 5 / 7) * 3 / (width / 7) + 4].v << 2,
				colors_bottom[((x+xsub) - width * 5 / 7) * 3 / (width / 7) + 4].u << 2,
				colors_bottom[((x+xsub) - width * 5 / 7) * 3 / (width / 7) + 4].v << 2);
		for (; x < width; x += xstep)
			write_pixels_10bpp(&uv_mem[(x * 5) / xstep],
				colors_bottom[7].u << 2,
				colors_bottom[7].v << 2,
				colors_bottom[7].u << 2,
				colors_bottom[7].v << 2);
		uv_mem += stride * cs / xsub;
	}
}

static void fill_smpte_yuv_packed(const struct util_yuv_info *yuv, void *mem,
				  unsigned int width, unsigned int height,
				  unsigned int stride)
{
	const struct color_yuv colors_top[] = {
		MAKE_YUV_601(192, 192, 192),	/* grey */
		MAKE_YUV_601(192, 192, 0),	/* yellow */
		MAKE_YUV_601(0, 192, 192),	/* cyan */
		MAKE_YUV_601(0, 192, 0),	/* green */
		MAKE_YUV_601(192, 0, 192),	/* magenta */
		MAKE_YUV_601(192, 0, 0),	/* red */
		MAKE_YUV_601(0, 0, 192),	/* blue */
	};
	const struct color_yuv colors_middle[] = {
		MAKE_YUV_601(0, 0, 192),	/* blue */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(192, 0, 192),	/* magenta */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(0, 192, 192),	/* cyan */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(192, 192, 192),	/* grey */
	};
	const struct color_yuv colors_bottom[] = {
		MAKE_YUV_601(0, 33, 76),	/* in-phase */
		MAKE_YUV_601(255, 255, 255),	/* super white */
		MAKE_YUV_601(50, 0, 106),	/* quadrature */
		MAKE_YUV_601(19, 19, 19),	/* black */
		MAKE_YUV_601(9, 9, 9),		/* 3.5% */
		MAKE_YUV_601(19, 19, 19),	/* 7.5% */
		MAKE_YUV_601(29, 29, 29),	/* 11.5% */
		MAKE_YUV_601(19, 19, 19),	/* black */
	};
	unsigned char *y_mem = (yuv->order & YUV_YC) ? mem : mem + 1;
	unsigned char *c_mem = (yuv->order & YUV_CY) ? mem : mem + 1;
	unsigned int u = (yuv->order & YUV_YCrCb) ? 2 : 0;
	unsigned int v = (yuv->order & YUV_YCbCr) ? 2 : 0;
	unsigned int x;
	unsigned int y;

	/* Luma */
	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			y_mem[2*x] = colors_top[x * 7 / width].y;
		y_mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			y_mem[2*x] = colors_middle[x * 7 / width].y;
		y_mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			y_mem[2*x] = colors_bottom[x * 4 / (width * 5 / 7)].y;
		for (; x < width * 6 / 7; ++x)
			y_mem[2*x] = colors_bottom[(x - width * 5 / 7) * 3
						   / (width / 7) + 4].y;
		for (; x < width; ++x)
			y_mem[2*x] = colors_bottom[7].y;
		y_mem += stride;
	}

	/* Chroma */
	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; x += 2) {
			c_mem[2*x+u] = colors_top[x * 7 / width].u;
			c_mem[2*x+v] = colors_top[x * 7 / width].v;
		}
		c_mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; x += 2) {
			c_mem[2*x+u] = colors_middle[x * 7 / width].u;
			c_mem[2*x+v] = colors_middle[x * 7 / width].v;
		}
		c_mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; x += 2) {
			c_mem[2*x+u] = colors_bottom[x * 4 / (width * 5 / 7)].u;
			c_mem[2*x+v] = colors_bottom[x * 4 / (width * 5 / 7)].v;
		}
		for (; x < width * 6 / 7; x += 2) {
			c_mem[2*x+u] = colors_bottom[(x - width * 5 / 7) *
						     3 / (width / 7) + 4].u;
			c_mem[2*x+v] = colors_bottom[(x - width * 5 / 7) *
						     3 / (width / 7) + 4].v;
		}
		for (; x < width; x += 2) {
			c_mem[2*x+u] = colors_bottom[7].u;
			c_mem[2*x+v] = colors_bottom[7].v;
		}
		c_mem += stride;
	}
}

static void fill_smpte_rgb16(const struct util_rgb_info *rgb, void *mem,
			     unsigned int width, unsigned int height,
			     unsigned int stride, bool fb_be)
{
	const uint16_t colors_top[] = {
		MAKE_RGBA(rgb, 192, 192, 192, 255),	/* grey */
		MAKE_RGBA(rgb, 192, 192, 0, 255),	/* yellow */
		MAKE_RGBA(rgb, 0, 192, 192, 255),	/* cyan */
		MAKE_RGBA(rgb, 0, 192, 0, 255),		/* green */
		MAKE_RGBA(rgb, 192, 0, 192, 255),	/* magenta */
		MAKE_RGBA(rgb, 192, 0, 0, 255),		/* red */
		MAKE_RGBA(rgb, 0, 0, 192, 255),		/* blue */
	};
	const uint16_t colors_middle[] = {
		MAKE_RGBA(rgb, 0, 0, 192, 127),		/* blue */
		MAKE_RGBA(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA(rgb, 192, 0, 192, 127),	/* magenta */
		MAKE_RGBA(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA(rgb, 0, 192, 192, 127),	/* cyan */
		MAKE_RGBA(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA(rgb, 192, 192, 192, 127),	/* grey */
	};
	const uint16_t colors_bottom[] = {
		MAKE_RGBA(rgb, 0, 33, 76, 255),		/* in-phase */
		MAKE_RGBA(rgb, 255, 255, 255, 255),	/* super white */
		MAKE_RGBA(rgb, 50, 0, 106, 255),	/* quadrature */
		MAKE_RGBA(rgb, 19, 19, 19, 255),	/* black */
		MAKE_RGBA(rgb, 9, 9, 9, 255),		/* 3.5% */
		MAKE_RGBA(rgb, 19, 19, 19, 255),	/* 7.5% */
		MAKE_RGBA(rgb, 29, 29, 29, 255),	/* 11.5% */
		MAKE_RGBA(rgb, 19, 19, 19, 255),	/* black */
	};
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint16_t *)mem)[x] = cpu_to_fb16(colors_top[x * 7 / width]);
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint16_t *)mem)[x] = cpu_to_fb16(colors_middle[x * 7 / width]);
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			((uint16_t *)mem)[x] =
				cpu_to_fb16(colors_bottom[x * 4 / (width * 5 / 7)]);
		for (; x < width * 6 / 7; ++x)
			((uint16_t *)mem)[x] =
				cpu_to_fb16(colors_bottom[(x - width * 5 / 7) * 3
							  / (width / 7) + 4]);
		for (; x < width; ++x)
			((uint16_t *)mem)[x] = cpu_to_fb16(colors_bottom[7]);
		mem += stride;
	}
}

static void fill_smpte_rgb24(const struct util_rgb_info *rgb, void *mem,
			     unsigned int width, unsigned int height,
			     unsigned int stride)
{
	const struct color_rgb24 colors_top[] = {
		MAKE_RGB24(rgb, 192, 192, 192),	/* grey */
		MAKE_RGB24(rgb, 192, 192, 0),	/* yellow */
		MAKE_RGB24(rgb, 0, 192, 192),	/* cyan */
		MAKE_RGB24(rgb, 0, 192, 0),	/* green */
		MAKE_RGB24(rgb, 192, 0, 192),	/* magenta */
		MAKE_RGB24(rgb, 192, 0, 0),	/* red */
		MAKE_RGB24(rgb, 0, 0, 192),	/* blue */
	};
	const struct color_rgb24 colors_middle[] = {
		MAKE_RGB24(rgb, 0, 0, 192),	/* blue */
		MAKE_RGB24(rgb, 19, 19, 19),	/* black */
		MAKE_RGB24(rgb, 192, 0, 192),	/* magenta */
		MAKE_RGB24(rgb, 19, 19, 19),	/* black */
		MAKE_RGB24(rgb, 0, 192, 192),	/* cyan */
		MAKE_RGB24(rgb, 19, 19, 19),	/* black */
		MAKE_RGB24(rgb, 192, 192, 192),	/* grey */
	};
	const struct color_rgb24 colors_bottom[] = {
		MAKE_RGB24(rgb, 0, 33, 76),	/* in-phase */
		MAKE_RGB24(rgb, 255, 255, 255),	/* super white */
		MAKE_RGB24(rgb, 50, 0, 106),	/* quadrature */
		MAKE_RGB24(rgb, 19, 19, 19),	/* black */
		MAKE_RGB24(rgb, 9, 9, 9),	/* 3.5% */
		MAKE_RGB24(rgb, 19, 19, 19),	/* 7.5% */
		MAKE_RGB24(rgb, 29, 29, 29),	/* 11.5% */
		MAKE_RGB24(rgb, 19, 19, 19),	/* black */
	};
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((struct color_rgb24 *)mem)[x] =
				colors_top[x * 7 / width];
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((struct color_rgb24 *)mem)[x] =
				colors_middle[x * 7 / width];
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			((struct color_rgb24 *)mem)[x] =
				colors_bottom[x * 4 / (width * 5 / 7)];
		for (; x < width * 6 / 7; ++x)
			((struct color_rgb24 *)mem)[x] =
				colors_bottom[(x - width * 5 / 7) * 3
					      / (width / 7) + 4];
		for (; x < width; ++x)
			((struct color_rgb24 *)mem)[x] = colors_bottom[7];
		mem += stride;
	}
}

static void fill_smpte_rgb32(const struct util_rgb_info *rgb, void *mem,
			     unsigned int width, unsigned int height,
			     unsigned int stride)
{
	const uint32_t colors_top[] = {
		MAKE_RGBA(rgb, 192, 192, 192, 255),	/* grey */
		MAKE_RGBA(rgb, 192, 192, 0, 255),	/* yellow */
		MAKE_RGBA(rgb, 0, 192, 192, 255),	/* cyan */
		MAKE_RGBA(rgb, 0, 192, 0, 255),		/* green */
		MAKE_RGBA(rgb, 192, 0, 192, 255),	/* magenta */
		MAKE_RGBA(rgb, 192, 0, 0, 255),		/* red */
		MAKE_RGBA(rgb, 0, 0, 192, 255),		/* blue */
	};
	const uint32_t colors_middle[] = {
		MAKE_RGBA(rgb, 0, 0, 192, 127),		/* blue */
		MAKE_RGBA(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA(rgb, 192, 0, 192, 127),	/* magenta */
		MAKE_RGBA(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA(rgb, 0, 192, 192, 127),	/* cyan */
		MAKE_RGBA(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA(rgb, 192, 192, 192, 127),	/* grey */
	};
	const uint32_t colors_bottom[] = {
		MAKE_RGBA(rgb, 0, 33, 76, 255),		/* in-phase */
		MAKE_RGBA(rgb, 255, 255, 255, 255),	/* super white */
		MAKE_RGBA(rgb, 50, 0, 106, 255),	/* quadrature */
		MAKE_RGBA(rgb, 19, 19, 19, 255),	/* black */
		MAKE_RGBA(rgb, 9, 9, 9, 255),		/* 3.5% */
		MAKE_RGBA(rgb, 19, 19, 19, 255),	/* 7.5% */
		MAKE_RGBA(rgb, 29, 29, 29, 255),	/* 11.5% */
		MAKE_RGBA(rgb, 19, 19, 19, 255),	/* black */
	};
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint32_t *)mem)[x] = cpu_to_le32(colors_top[x * 7 / width]);
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint32_t *)mem)[x] = cpu_to_le32(colors_middle[x * 7 / width]);
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			((uint32_t *)mem)[x] =
				cpu_to_le32(colors_bottom[x * 4 / (width * 5 / 7)]);
		for (; x < width * 6 / 7; ++x)
			((uint32_t *)mem)[x] =
				cpu_to_le32(colors_bottom[(x - width * 5 / 7) * 3
							  / (width / 7) + 4]);
		for (; x < width; ++x)
			((uint32_t *)mem)[x] = cpu_to_le32(colors_bottom[7]);
		mem += stride;
	}
}

static void fill_smpte_rgb16fp(const struct util_rgb_info *rgb, void *mem,
			       unsigned int width, unsigned int height,
			       unsigned int stride)
{
	const uint64_t colors_top[] = {
		MAKE_RGBA8FP16(rgb, 192, 192, 192, 255),/* grey */
		MAKE_RGBA8FP16(rgb, 192, 192, 0, 255),	/* yellow */
		MAKE_RGBA8FP16(rgb, 0, 192, 192, 255),	/* cyan */
		MAKE_RGBA8FP16(rgb, 0, 192, 0, 255),	/* green */
		MAKE_RGBA8FP16(rgb, 192, 0, 192, 255),	/* magenta */
		MAKE_RGBA8FP16(rgb, 192, 0, 0, 255),	/* red */
		MAKE_RGBA8FP16(rgb, 0, 0, 192, 255),	/* blue */
	};
	const uint64_t colors_middle[] = {
		MAKE_RGBA8FP16(rgb, 0, 0, 192, 127),	/* blue */
		MAKE_RGBA8FP16(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA8FP16(rgb, 192, 0, 192, 127),	/* magenta */
		MAKE_RGBA8FP16(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA8FP16(rgb, 0, 192, 192, 127),	/* cyan */
		MAKE_RGBA8FP16(rgb, 19, 19, 19, 127),	/* black */
		MAKE_RGBA8FP16(rgb, 192, 192, 192, 127),/* grey */
	};
	const uint64_t colors_bottom[] = {
		MAKE_RGBA8FP16(rgb, 0, 33, 76, 255),	/* in-phase */
		MAKE_RGBA8FP16(rgb, 255, 255, 255, 255),/* super white */
		MAKE_RGBA8FP16(rgb, 50, 0, 106, 255),	/* quadrature */
		MAKE_RGBA8FP16(rgb, 19, 19, 19, 255),	/* black */
		MAKE_RGBA8FP16(rgb, 9, 9, 9, 255),	/* 3.5% */
		MAKE_RGBA8FP16(rgb, 19, 19, 19, 255),	/* 7.5% */
		MAKE_RGBA8FP16(rgb, 29, 29, 29, 255),	/* 11.5% */
		MAKE_RGBA8FP16(rgb, 19, 19, 19, 255),	/* black */
	};
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint64_t *)mem)[x] = colors_top[x * 7 / width];
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint64_t *)mem)[x] = colors_middle[x * 7 / width];
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			((uint64_t *)mem)[x] =
				colors_bottom[x * 4 / (width * 5 / 7)];
		for (; x < width * 6 / 7; ++x)
			((uint64_t *)mem)[x] =
				colors_bottom[(x - width * 5 / 7) * 3
					      / (width / 7) + 4];
		for (; x < width; ++x)
			((uint64_t *)mem)[x] = colors_bottom[7];
		mem += stride;
	}
}

enum smpte_colors {
	SMPTE_COLOR_GREY,
	SMPTE_COLOR_YELLOW,
	SMPTE_COLOR_CYAN,
	SMPTE_COLOR_GREEN,
	SMPTE_COLOR_MAGENTA,
	SMPTE_COLOR_RED,
	SMPTE_COLOR_BLUE,
	SMPTE_COLOR_BLACK,
	SMPTE_COLOR_IN_PHASE,
	SMPTE_COLOR_SUPER_WHITE,
	SMPTE_COLOR_QUADRATURE,
	SMPTE_COLOR_3PC5,
	SMPTE_COLOR_11PC5,
};

static unsigned int smpte_top[7] = {
	SMPTE_COLOR_GREY,
	SMPTE_COLOR_YELLOW,
	SMPTE_COLOR_CYAN,
	SMPTE_COLOR_GREEN,
	SMPTE_COLOR_MAGENTA,
	SMPTE_COLOR_RED,
	SMPTE_COLOR_BLUE,
};

static unsigned int smpte_middle[7] = {
	SMPTE_COLOR_BLUE,
	SMPTE_COLOR_BLACK,
	SMPTE_COLOR_MAGENTA,
	SMPTE_COLOR_BLACK,
	SMPTE_COLOR_CYAN,
	SMPTE_COLOR_BLACK,
	SMPTE_COLOR_GREY,
};

static unsigned int smpte_bottom[8] = {
	SMPTE_COLOR_IN_PHASE,
	SMPTE_COLOR_SUPER_WHITE,
	SMPTE_COLOR_QUADRATURE,
	SMPTE_COLOR_BLACK,
	SMPTE_COLOR_3PC5,
	SMPTE_COLOR_BLACK,
	SMPTE_COLOR_11PC5,
	SMPTE_COLOR_BLACK,
};

#define EXPAND_COLOR(r, g, b)	{ (r) * 0x101, (g) * 0x101, (b) * 0x101 }

static const struct drm_color_lut bw_color_lut[] = {
	EXPAND_COLOR(  0,   0,   0),	/* black */
	EXPAND_COLOR(255, 255, 255),	/* white */
};

static const struct drm_color_lut pentile_color_lut[] = {
	/* PenTile RG-GB */
	EXPAND_COLOR(  0,   0,   0),	/* black */
	EXPAND_COLOR(255,   0,   0),	/* red */
	EXPAND_COLOR(  0, 207,   0),	/* green */
	EXPAND_COLOR(  0,   0, 255),	/* blue */
};

static const struct drm_color_lut smpte_color_lut[] = {
	[SMPTE_COLOR_GREY] =        EXPAND_COLOR(192, 192, 192),
	[SMPTE_COLOR_YELLOW] =      EXPAND_COLOR(192, 192,   0),
	[SMPTE_COLOR_CYAN] =        EXPAND_COLOR(  0, 192, 192),
	[SMPTE_COLOR_GREEN] =       EXPAND_COLOR(  0, 192,   0),
	[SMPTE_COLOR_MAGENTA] =     EXPAND_COLOR(192,   0, 192),
	[SMPTE_COLOR_RED] =         EXPAND_COLOR(192,   0,   0),
	[SMPTE_COLOR_BLUE] =        EXPAND_COLOR(  0,   0, 192),
	[SMPTE_COLOR_BLACK] =       EXPAND_COLOR( 19,  19,  19),
	[SMPTE_COLOR_IN_PHASE] =    EXPAND_COLOR(  0,  33,  76),
	[SMPTE_COLOR_SUPER_WHITE] = EXPAND_COLOR(255, 255, 255),
	[SMPTE_COLOR_QUADRATURE] =  EXPAND_COLOR( 50,   0, 106),
	[SMPTE_COLOR_3PC5] =        EXPAND_COLOR(  9,   9,   9),
	[SMPTE_COLOR_11PC5] =       EXPAND_COLOR( 29,  29,  29),
};

#undef EXPAND_COLOR

/*
 * Floyd-Steinberg dithering
 */

struct fsd {
	unsigned int width;
	unsigned int x;
	unsigned int i;
	int red;
	int green;
	int blue;
	int error[];
};

static struct fsd *fsd_alloc(unsigned int width)
{
	unsigned int n = 3 * (width + 1);
	struct fsd *fsd = malloc(sizeof(*fsd) + n * sizeof(fsd->error[0]));

	fsd->width = width;
	fsd->x = 0;
	fsd->i = 0;
	memset(fsd->error, 0, n * sizeof(fsd->error[0]));

	return fsd;
}

static inline int clamp(int val, int min, int max)
{
	if (val < min)
		return min;
	if (val > max)
		return max;
	return val;
}

static void fsd_dither(struct fsd *fsd, struct drm_color_lut *color)
{
	unsigned int i = fsd->i;

	fsd->red = (int)color->red + (fsd->error[3 * i] + 8) / 16;
	fsd->green = (int)color->green + (fsd->error[3 * i + 1] + 8) / 16;
	fsd->blue = (int)color->blue + (fsd->error[3 * i + 2] + 8) / 16;

	color->red = clamp(fsd->red, 0, 65535);
	color->green = clamp(fsd->green, 0, 65535);
	color->blue = clamp(fsd->blue, 0, 65535);
}

static void fsd_update(struct fsd *fsd, const struct drm_color_lut *actual)
{
	int error_red = fsd->red - (int)actual->red;
	int error_green = fsd->green - (int)actual->green;
	int error_blue = fsd->blue - (int)actual->blue;
	unsigned int width = fsd->width;
	unsigned int i = fsd->i, j;
	unsigned int n = width + 1;

	/* Distribute errors over neighboring pixels */
	if (fsd->x == width - 1) {
		/* Last pixel on this scanline */
		/* South East: initialize to zero */
		fsd->error[3 * i] = 0;
		fsd->error[3 * i + 1] = 0;
		fsd->error[3 * i + 2] = 0;
	} else {
		/* East: accumulate error */
		j = (i + 1) % n;
		fsd->error[3 * j] += 7 * error_red;
		fsd->error[3 * j + 1] += 7 * error_green;
		fsd->error[3 * j + 2] += 7 * error_blue;

		/* South East: initial error */
		fsd->error[3 * i] = error_red;
		fsd->error[3 * i + 1] = error_green;
		fsd->error[3 * i + 2] = error_blue;
	}
	/* South West: accumulate error */
	j = (i + width - 1) % n;
	fsd->error[3 * j] += 3 * error_red;
	fsd->error[3 * j + 1] += 3 * error_green;
	fsd->error[3 * j + 2] += 3 * error_blue;

	/* South: accumulate error */
	j = (i + width) % n;
	fsd->error[3 * j] += 5 * error_red;
	fsd->error[3 * j + 1] += 5 * error_green;
	fsd->error[3 * j + 2] += 5 * error_blue;

	fsd->x = (fsd->x + 1) % width;
	fsd->i = (fsd->i + 1) % n;
}

static void write_pixel_1(uint8_t *mem, unsigned int x, unsigned int pixel)
{
	unsigned int shift = 7 - (x & 7);
	unsigned int mask = 1U << shift;

	mem[x / 8] = (mem[x / 8] & ~mask) | ((pixel << shift) & mask);
}

static void write_color_1(struct fsd *fsd, uint8_t *mem, unsigned int x,
			  unsigned int index)
{
	struct drm_color_lut color = smpte_color_lut[index];
	unsigned int pixel;

	fsd_dither(fsd, &color);

	/* ITU BT.601: Y = 0.299 R + 0.587 G + 0.114 B */
	if (3 * color.red + 6 * color.green + color.blue >= 10 * 32768) {
		pixel = 1;
		color.red = color.green = color.blue = 65535;
	} else {
		pixel = 0;
		color.red = color.green = color.blue = 0;
	}

	fsd_update(fsd, &color);

	write_pixel_1(mem, x, pixel);
}

static void fill_smpte_c1(void *mem, unsigned int width, unsigned int height,
			  unsigned int stride)
{
	struct fsd *fsd = fsd_alloc(width);
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			write_color_1(fsd, mem, x, smpte_top[x * 7 / width]);
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			write_color_1(fsd, mem, x, smpte_middle[x * 7 / width]);
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			write_color_1(fsd, mem, x,
				      smpte_bottom[x * 4 / (width * 5 / 7)]);
		for (; x < width * 6 / 7; ++x)
			write_color_1(fsd, mem, x,
				      smpte_bottom[(x - width * 5 / 7) * 3 /
						   (width / 7) + 4]);
		for (; x < width; ++x)
			write_color_1(fsd, mem, x, smpte_bottom[7]);
		mem += stride;
	}

	free(fsd);
}

static void write_pixel_2(uint8_t *mem, unsigned int x, unsigned int pixel)
{
	unsigned int shift = 6 - 2 * (x & 3);
	unsigned int mask = 3U << shift;

	mem[x / 4] = (mem[x / 4] & ~mask) | ((pixel << shift) & mask);
}

static void write_color_2(struct fsd *fsd, uint8_t *mem, unsigned int stride,
			  unsigned int x, unsigned int index)
{
	struct drm_color_lut color = smpte_color_lut[index];
	unsigned int r, g, b;

	fsd_dither(fsd, &color);

	if (color.red >= 32768) {
		r = 1;
		color.red = 65535;
	} else {
		r = 0;
		color.red = 0;
	}
	if (color.green >= 32768) {
		g = 2;
		color.green = 65535;
	} else {
		g = 0;
		color.green = 0;
	}
	if (color.blue >= 32768) {
		b = 3;
		color.blue = 65535;
	} else {
		b = 0;
		color.blue = 0;
	}

	fsd_update(fsd, &color);

	/* Use PenTile RG-GB */
	write_pixel_2(mem, 2 * x, r);
	write_pixel_2(mem, 2 * x + 1, g);
	write_pixel_2(mem + stride, 2 * x, g);
	write_pixel_2(mem + stride, 2 * x + 1, b);
}

static void fill_smpte_c2(void *mem, unsigned int width, unsigned int height,
			  unsigned int stride)
{
	struct fsd *fsd = fsd_alloc(width);
	unsigned int x;
	unsigned int y;

	/* Half resolution for PenTile RG-GB */
	width /= 2;
	height /= 2;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			write_color_2(fsd, mem, stride, x, smpte_top[x * 7 / width]);
		mem += 2 * stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			write_color_2(fsd, mem, stride, x, smpte_middle[x * 7 / width]);
		mem += 2 * stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			write_color_2(fsd, mem, stride, x,
				      smpte_bottom[x * 4 / (width * 5 / 7)]);
		for (; x < width * 6 / 7; ++x)
			write_color_2(fsd, mem, stride, x,
				      smpte_bottom[(x - width * 5 / 7) * 3 /
						   (width / 7) + 4]);
		for (; x < width; ++x)
			write_color_2(fsd, mem, stride, x, smpte_bottom[7]);
		mem += 2 * stride;
	}

	free(fsd);
}

static void write_pixel_4(uint8_t *mem, unsigned int x, unsigned int pixel)
{
	if (x & 1)
		mem[x / 2] = (mem[x / 2] & 0xf0) | (pixel & 0x0f);
	else
		mem[x / 2] = (mem[x / 2] & 0x0f) | (pixel << 4);
}

static void fill_smpte_c4(void *mem, unsigned int width, unsigned int height,
			  unsigned int stride)
{
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			write_pixel_4(mem, x, smpte_top[x * 7 / width]);
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			write_pixel_4(mem, x, smpte_middle[x * 7 / width]);
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			write_pixel_4(mem, x,
				      smpte_bottom[x * 4 / (width * 5 / 7)]);
		for (; x < width * 6 / 7; ++x)
			write_pixel_4(mem, x,
				      smpte_bottom[(x - width * 5 / 7) * 3 /
						   (width / 7) + 4]);
		for (; x < width; ++x)
			write_pixel_4(mem, x, smpte_bottom[7]);
		mem += stride;
	}
}

static void fill_smpte_c8(void *mem, unsigned int width, unsigned int height,
			  unsigned int stride)
{
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height * 6 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint8_t *)mem)[x] = smpte_top[x * 7 / width];
		mem += stride;
	}

	for (; y < height * 7 / 9; ++y) {
		for (x = 0; x < width; ++x)
			((uint8_t *)mem)[x] = smpte_middle[x * 7 / width];
		mem += stride;
	}

	for (; y < height; ++y) {
		for (x = 0; x < width * 5 / 7; ++x)
			((uint8_t *)mem)[x] =
				smpte_bottom[x * 4 / (width * 5 / 7)];
		for (; x < width * 6 / 7; ++x)
			((uint8_t *)mem)[x] =
				smpte_bottom[(x - width * 5 / 7) * 3
					     / (width / 7) + 4];
		for (; x < width; ++x)
			((uint8_t *)mem)[x] = smpte_bottom[7];
		mem += stride;
	}
}

void util_smpte_fill_lut(unsigned int ncolors, struct drm_color_lut *lut)
{
	if (ncolors < ARRAY_SIZE(bw_color_lut)) {
		printf("Error: lut too small: %u < %zu\n", ncolors,
		       ARRAY_SIZE(bw_color_lut));
		return;
	}
	memset(lut, 0, ncolors * sizeof(struct drm_color_lut));

	if (ncolors < ARRAY_SIZE(pentile_color_lut))
		memcpy(lut, bw_color_lut, sizeof(bw_color_lut));
	else if (ncolors < ARRAY_SIZE(smpte_color_lut))
		memcpy(lut, pentile_color_lut, sizeof(pentile_color_lut));
	else
		memcpy(lut, smpte_color_lut, sizeof(smpte_color_lut));
}

static void fill_smpte(const struct util_format_info *info, void *planes[3],
		       unsigned int width, unsigned int height,
		       unsigned int stride)
{
	unsigned char *u, *v;

	switch (info->format) {
	case DRM_FORMAT_C1:
		return fill_smpte_c1(planes[0], width, height, stride);
	case DRM_FORMAT_C2:
		return fill_smpte_c2(planes[0], width, height, stride);
	case DRM_FORMAT_C4:
		return fill_smpte_c4(planes[0], width, height, stride);
	case DRM_FORMAT_C8:
		return fill_smpte_c8(planes[0], width, height, stride);
	case DRM_FORMAT_UYVY:
	case DRM_FORMAT_VYUY:
	case DRM_FORMAT_YUYV:
	case DRM_FORMAT_YVYU:
		return fill_smpte_yuv_packed(&info->yuv, planes[0], width,
					     height, stride);

	case DRM_FORMAT_NV12:
	case DRM_FORMAT_NV21:
	case DRM_FORMAT_NV16:
	case DRM_FORMAT_NV61:
	case DRM_FORMAT_NV24:
	case DRM_FORMAT_NV42:
		u = info->yuv.order & YUV_YCbCr ? planes[1] : planes[1] + 1;
		v = info->yuv.order & YUV_YCrCb ? planes[1] : planes[1] + 1;
		return fill_smpte_yuv_planar(&info->yuv, planes[0], u, v,
					     width, height, stride);

	case DRM_FORMAT_NV15:
	case DRM_FORMAT_NV20:
	case DRM_FORMAT_NV30:
		return fill_smpte_yuv_planar_10bpp(&info->yuv, planes[0],
						   planes[1], width, height,
						   stride);

	case DRM_FORMAT_YUV420:
	case DRM_FORMAT_YUV422:
	case DRM_FORMAT_YUV444:
		return fill_smpte_yuv_planar(&info->yuv, planes[0], planes[1],
					     planes[2], width, height, stride);

	case DRM_FORMAT_YVU420:
	case DRM_FORMAT_YVU422:
	case DRM_FORMAT_YVU444:
		return fill_smpte_yuv_planar(&info->yuv, planes[0], planes[2],
					     planes[1], width, height, stride);

	case DRM_FORMAT_ARGB4444:
	case DRM_FORMAT_XRGB4444:
	case DRM_FORMAT_ABGR4444:
	case DRM_FORMAT_XBGR4444:
	case DRM_FORMAT_RGBA4444:
	case DRM_FORMAT_RGBX4444:
	case DRM_FORMAT_BGRA4444:
	case DRM_FORMAT_BGRX4444:
	case DRM_FORMAT_RGB565:
	case DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN:
	case DRM_FORMAT_BGR565:
	case DRM_FORMAT_ARGB1555:
	case DRM_FORMAT_XRGB1555:
	case DRM_FORMAT_XRGB1555 | DRM_FORMAT_BIG_ENDIAN:
	case DRM_FORMAT_ABGR1555:
	case DRM_FORMAT_XBGR1555:
	case DRM_FORMAT_RGBA5551:
	case DRM_FORMAT_RGBX5551:
	case DRM_FORMAT_BGRA5551:
	case DRM_FORMAT_BGRX5551:
		return fill_smpte_rgb16(&info->rgb, planes[0],
					width, height, stride,
					info->format & DRM_FORMAT_BIG_ENDIAN);

	case DRM_FORMAT_BGR888:
	case DRM_FORMAT_RGB888:
		return fill_smpte_rgb24(&info->rgb, planes[0],
					width, height, stride);
	case DRM_FORMAT_ARGB8888:
	case DRM_FORMAT_XRGB8888:
	case DRM_FORMAT_ABGR8888:
	case DRM_FORMAT_XBGR8888:
	case DRM_FORMAT_RGBA8888:
	case DRM_FORMAT_RGBX8888:
	case DRM_FORMAT_BGRA8888:
	case DRM_FORMAT_BGRX8888:
	case DRM_FORMAT_ARGB2101010:
	case DRM_FORMAT_XRGB2101010:
	case DRM_FORMAT_ABGR2101010:
	case DRM_FORMAT_XBGR2101010:
	case DRM_FORMAT_RGBA1010102:
	case DRM_FORMAT_RGBX1010102:
	case DRM_FORMAT_BGRA1010102:
	case DRM_FORMAT_BGRX1010102:
		return fill_smpte_rgb32(&info->rgb, planes[0],
					width, height, stride);

	case DRM_FORMAT_XRGB16161616F:
	case DRM_FORMAT_XBGR16161616F:
	case DRM_FORMAT_ARGB16161616F:
	case DRM_FORMAT_ABGR16161616F:
		return fill_smpte_rgb16fp(&info->rgb, planes[0],
					  width, height, stride);
	}
}

#if HAVE_CAIRO
static void byteswap_buffer16(void *mem, unsigned int width, unsigned int height,
			      unsigned int stride)
{
	unsigned int x, y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x)
			((uint16_t *)mem)[x] = swap16(((uint16_t *)mem)[x]);
		mem += stride;
	}
}

static void byteswap_buffer32(void *mem, unsigned int width, unsigned int height,
			      unsigned int stride)
{
	unsigned int x, y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x)
			((uint32_t *)mem)[x] = swap32(((uint32_t *)mem)[x]);
		mem += stride;
	}
}
#endif

static void make_pwetty(void *data, unsigned int width, unsigned int height,
			unsigned int stride, uint32_t format)
{
#if HAVE_CAIRO
	cairo_surface_t *surface;
	cairo_t *cr;
	cairo_format_t cairo_format;
	bool swap16 = false;
	bool swap32 = false;

	/* we can ignore the order of R,G,B channels */
	switch (format) {
	case DRM_FORMAT_XRGB8888:
	case DRM_FORMAT_ARGB8888:
	case DRM_FORMAT_XBGR8888:
	case DRM_FORMAT_ABGR8888:
		cairo_format = CAIRO_FORMAT_ARGB32;
		break;
	case DRM_FORMAT_RGB565:
	case DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN:
	case DRM_FORMAT_BGR565:
		cairo_format = CAIRO_FORMAT_RGB16_565;
		swap16 = fb_foreign_endian(format);
		break;
#if CAIRO_VERSION_MAJOR > 1 || (CAIRO_VERSION_MAJOR == 1 && CAIRO_VERSION_MINOR >= 12)
	case DRM_FORMAT_ARGB2101010:
	case DRM_FORMAT_XRGB2101010:
	case DRM_FORMAT_ABGR2101010:
	case DRM_FORMAT_XBGR2101010:
		cairo_format = CAIRO_FORMAT_RGB30;
		swap32 = fb_foreign_endian(format);
		break;
#endif
	default:
		return;
	}

	/* Cairo uses native byte order, so we may have to byteswap before... */
	if (swap16)
		byteswap_buffer16(data, width, height, stride);
	if (swap32)
		byteswap_buffer32(data, width, height, stride);

	surface = cairo_image_surface_create_for_data(data,
						      cairo_format,
						      width, height,
						      stride);
	cr = cairo_create(surface);
	cairo_surface_destroy(surface);

	cairo_set_line_cap(cr, CAIRO_LINE_CAP_SQUARE);
	for (unsigned x = 0; x < width; x += 250)
		for (unsigned y = 0; y < height; y += 250) {
			char buf[64];

			cairo_move_to(cr, x, y - 20);
			cairo_line_to(cr, x, y + 20);
			cairo_move_to(cr, x - 20, y);
			cairo_line_to(cr, x + 20, y);
			cairo_new_sub_path(cr);
			cairo_arc(cr, x, y, 10, 0, M_PI * 2);
			cairo_set_line_width(cr, 4);
			cairo_set_source_rgb(cr, 0, 0, 0);
			cairo_stroke_preserve(cr);
			cairo_set_source_rgb(cr, 1, 1, 1);
			cairo_set_line_width(cr, 2);
			cairo_stroke(cr);

			snprintf(buf, sizeof buf, "%d, %d", x, y);
			cairo_move_to(cr, x + 20, y + 20);
			cairo_text_path(cr, buf);
			cairo_set_source_rgb(cr, 0, 0, 0);
			cairo_stroke_preserve(cr);
			cairo_set_source_rgb(cr, 1, 1, 1);
			cairo_fill(cr);
		}

	cairo_destroy(cr);

	/* ... and after */
	if (swap16)
		byteswap_buffer16(data, width, height, stride);
	if (swap32)
		byteswap_buffer32(data, width, height, stride);
#endif
}

static struct color_yuv make_tiles_yuv_color(unsigned int x, unsigned int y,
					     unsigned int width)
{
	div_t d = div(x+y, width);
	uint32_t rgb32 = 0x00130502 * (d.quot >> 6)
		       + 0x000a1120 * (d.rem >> 6);
	struct color_yuv color =
		MAKE_YUV_601((rgb32 >> 16) & 0xff, (rgb32 >> 8) & 0xff,
			     rgb32 & 0xff);
	return color;
}

static void fill_tiles_yuv_planar(const struct util_format_info *info,
				  unsigned char *y_mem, unsigned char *u_mem,
				  unsigned char *v_mem, unsigned int width,
				  unsigned int height, unsigned int stride)
{
	const struct util_yuv_info *yuv = &info->yuv;
	unsigned int cs = yuv->chroma_stride;
	unsigned int xsub = yuv->xsub;
	unsigned int ysub = yuv->ysub;
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x) {
			struct color_yuv color =
				make_tiles_yuv_color(x, y, width);

			y_mem[x] = color.y;
			u_mem[x/xsub*cs] = color.u;
			v_mem[x/xsub*cs] = color.v;
		}

		y_mem += stride;
		if ((y + 1) % ysub == 0) {
			u_mem += stride * cs / xsub;
			v_mem += stride * cs / xsub;
		}
	}
}

static void fill_tiles_yuv_planar_10bpp(const struct util_format_info *info,
					unsigned char *y_mem,
					unsigned char *uv_mem,
					unsigned int width,
					unsigned int height,
					unsigned int stride)
{
	const struct util_yuv_info *yuv = &info->yuv;
	unsigned int cs = yuv->chroma_stride;
	unsigned int xsub = yuv->xsub;
	unsigned int ysub = yuv->ysub;
	unsigned int xstep = cs * xsub;
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; x += 4) {
			struct color_yuv a = make_tiles_yuv_color(x+0, y, width);
			struct color_yuv b = make_tiles_yuv_color(x+1, y, width);
			struct color_yuv c = make_tiles_yuv_color(x+2, y, width);
			struct color_yuv d = make_tiles_yuv_color(x+3, y, width);

			write_pixels_10bpp(&y_mem[(x * 5) / 4],
				a.y << 2, b.y << 2, c.y << 2, d.y << 2);
		}
		y_mem += stride;
	}
	for (y = 0; y < height; y += ysub) {
		for (x = 0; x < width; x += xstep) {
			struct color_yuv a = make_tiles_yuv_color(x+0, y, width);
			struct color_yuv b = make_tiles_yuv_color(x+xsub, y, width);

			write_pixels_10bpp(&uv_mem[(x * 5) / xstep],
				a.u << 2, a.v << 2, b.u << 2, b.v << 2);
		}
		uv_mem += stride * cs / xsub;
	}
}

static void fill_tiles_yuv_packed(const struct util_format_info *info,
				  void *mem, unsigned int width,
				  unsigned int height, unsigned int stride)
{
	const struct util_yuv_info *yuv = &info->yuv;
	unsigned char *y_mem = (yuv->order & YUV_YC) ? mem : mem + 1;
	unsigned char *c_mem = (yuv->order & YUV_CY) ? mem : mem + 1;
	unsigned int u = (yuv->order & YUV_YCrCb) ? 2 : 0;
	unsigned int v = (yuv->order & YUV_YCbCr) ? 2 : 0;
	unsigned int x;
	unsigned int y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; x += 2) {
			struct color_yuv color =
				make_tiles_yuv_color(x, y, width);

			y_mem[2*x] = color.y;
			c_mem[2*x+u] = color.u;
			y_mem[2*x+2] = color.y;
			c_mem[2*x+v] = color.v;
		}

		y_mem += stride;
		c_mem += stride;
	}
}

static void fill_tiles_rgb16(const struct util_format_info *info, void *mem,
			     unsigned int width, unsigned int height,
			     unsigned int stride, bool fb_be)
{
	const struct util_rgb_info *rgb = &info->rgb;
	void *mem_base = mem;
	unsigned int x, y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x) {
			div_t d = div(x+y, width);
			uint32_t rgb32 = 0x00130502 * (d.quot >> 6)
				       + 0x000a1120 * (d.rem >> 6);
			uint16_t color =
				MAKE_RGBA(rgb, (rgb32 >> 16) & 0xff,
					  (rgb32 >> 8) & 0xff, rgb32 & 0xff,
					  255);

			((uint16_t *)mem)[x] = cpu_to_fb16(color);
		}
		mem += stride;
	}

	make_pwetty(mem_base, width, height, stride, info->format);
}

static void fill_tiles_rgb24(const struct util_format_info *info, void *mem,
			     unsigned int width, unsigned int height,
			     unsigned int stride)
{
	const struct util_rgb_info *rgb = &info->rgb;
	unsigned int x, y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x) {
			div_t d = div(x+y, width);
			uint32_t rgb32 = 0x00130502 * (d.quot >> 6)
				       + 0x000a1120 * (d.rem >> 6);
			struct color_rgb24 color =
				MAKE_RGB24(rgb, (rgb32 >> 16) & 0xff,
					   (rgb32 >> 8) & 0xff, rgb32 & 0xff);

			((struct color_rgb24 *)mem)[x] = color;
		}
		mem += stride;
	}
}

static void fill_tiles_rgb32(const struct util_format_info *info, void *mem,
			     unsigned int width, unsigned int height,
			     unsigned int stride)
{
	const struct util_rgb_info *rgb = &info->rgb;
	void *mem_base = mem;
	unsigned int x, y;

	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x) {
			div_t d = div(x+y, width);
			uint32_t rgb32 = 0x00130502 * (d.quot >> 6)
				       + 0x000a1120 * (d.rem >> 6);
			uint32_t alpha = ((y < height/2) && (x < width/2)) ? 127 : 255;
			uint32_t color =
				MAKE_RGBA(rgb, (rgb32 >> 16) & 0xff,
					  (rgb32 >> 8) & 0xff, rgb32 & 0xff,
					  alpha);

			((uint32_t *)mem)[x] = cpu_to_le32(color);
		}
		mem += stride;
	}

	make_pwetty(mem_base, width, height, stride, info->format);
}

static void fill_tiles_rgb16fp(const struct util_format_info *info, void *mem,
			       unsigned int width, unsigned int height,
			       unsigned int stride)
{
	const struct util_rgb_info *rgb = &info->rgb;
	unsigned int x, y;

	/* TODO: Give this actual fp16 precision */
	for (y = 0; y < height; ++y) {
		for (x = 0; x < width; ++x) {
			div_t d = div(x+y, width);
			uint32_t rgb32 = 0x00130502 * (d.quot >> 6)
				       + 0x000a1120 * (d.rem >> 6);
			uint32_t alpha = ((y < height/2) && (x < width/2)) ? 127 : 255;
			uint64_t color =
				MAKE_RGBA8FP16(rgb, (rgb32 >> 16) & 0xff,
					       (rgb32 >> 8) & 0xff, rgb32 & 0xff,
					       alpha);

			((uint64_t *)mem)[x] = color;
		}
		mem += stride;
	}
}

static void fill_tiles(const struct util_format_info *info, void *planes[3],
		       unsigned int width, unsigned int height,
		       unsigned int stride)
{
	unsigned char *u, *v;

	switch (info->format) {
	case DRM_FORMAT_UYVY:
	case DRM_FORMAT_VYUY:
	case DRM_FORMAT_YUYV:
	case DRM_FORMAT_YVYU:
		return fill_tiles_yuv_packed(info, planes[0],
					     width, height, stride);

	case DRM_FORMAT_NV12:
	case DRM_FORMAT_NV21:
	case DRM_FORMAT_NV16:
	case DRM_FORMAT_NV61:
	case DRM_FORMAT_NV24:
	case DRM_FORMAT_NV42:
		u = info->yuv.order & YUV_YCbCr ? planes[1] : planes[1] + 1;
		v = info->yuv.order & YUV_YCrCb ? planes[1] : planes[1] + 1;
		return fill_tiles_yuv_planar(info, planes[0], u, v,
					     width, height, stride);

	case DRM_FORMAT_NV15:
	case DRM_FORMAT_NV20:
	case DRM_FORMAT_NV30:
		return fill_tiles_yuv_planar_10bpp(info, planes[0], planes[1],
						   width, height, stride);

	case DRM_FORMAT_YUV420:
	case DRM_FORMAT_YUV422:
	case DRM_FORMAT_YUV444:
		return fill_tiles_yuv_planar(info, planes[0], planes[1],
					     planes[2], width, height, stride);

	case DRM_FORMAT_YVU420:
	case DRM_FORMAT_YVU422:
	case DRM_FORMAT_YVU444:
		return fill_tiles_yuv_planar(info, planes[0], planes[2],
					     planes[1], width, height, stride);

	case DRM_FORMAT_ARGB4444:
	case DRM_FORMAT_XRGB4444:
	case DRM_FORMAT_ABGR4444:
	case DRM_FORMAT_XBGR4444:
	case DRM_FORMAT_RGBA4444:
	case DRM_FORMAT_RGBX4444:
	case DRM_FORMAT_BGRA4444:
	case DRM_FORMAT_BGRX4444:
	case DRM_FORMAT_RGB565:
	case DRM_FORMAT_RGB565 | DRM_FORMAT_BIG_ENDIAN:
	case DRM_FORMAT_BGR565:
	case DRM_FORMAT_ARGB1555:
	case DRM_FORMAT_XRGB1555:
	case DRM_FORMAT_XRGB1555 | DRM_FORMAT_BIG_ENDIAN:
	case DRM_FORMAT_ABGR1555:
	case DRM_FORMAT_XBGR1555:
	case DRM_FORMAT_RGBA5551:
	case DRM_FORMAT_RGBX5551:
	case DRM_FORMAT_BGRA5551:
	case DRM_FORMAT_BGRX5551:
		return fill_tiles_rgb16(info, planes[0],
					width, height, stride,
					info->format & DRM_FORMAT_BIG_ENDIAN);

	case DRM_FORMAT_BGR888:
	case DRM_FORMAT_RGB888:
		return fill_tiles_rgb24(info, planes[0],
					width, height, stride);
	case DRM_FORMAT_ARGB8888:
	case DRM_FORMAT_XRGB8888:
	case DRM_FORMAT_ABGR8888:
	case DRM_FORMAT_XBGR8888:
	case DRM_FORMAT_RGBA8888:
	case DRM_FORMAT_RGBX8888:
	case DRM_FORMAT_BGRA8888:
	case DRM_FORMAT_BGRX8888:
	case DRM_FORMAT_ARGB2101010:
	case DRM_FORMAT_XRGB2101010:
	case DRM_FORMAT_ABGR2101010:
	case DRM_FORMAT_XBGR2101010:
	case DRM_FORMAT_RGBA1010102:
	case DRM_FORMAT_RGBX1010102:
	case DRM_FORMAT_BGRA1010102:
	case DRM_FORMAT_BGRX1010102:
		return fill_tiles_rgb32(info, planes[0],
					width, height, stride);

	case DRM_FORMAT_XRGB16161616F:
	case DRM_FORMAT_XBGR16161616F:
	case DRM_FORMAT_ARGB16161616F:
	case DRM_FORMAT_ABGR16161616F:
		return fill_tiles_rgb16fp(info, planes[0],
					  width, height, stride);
	}
}

static void fill_plain(const struct util_format_info *info, void *planes[3],
		       unsigned int height,
		       unsigned int stride)
{
	switch (info->format) {
	case DRM_FORMAT_XRGB16161616F:
	case DRM_FORMAT_XBGR16161616F:
	case DRM_FORMAT_ARGB16161616F:
	case DRM_FORMAT_ABGR16161616F:
		/* 0x3838 = 0.5273 */
		memset(planes[0], 0x38, stride * height);
		break;
	default:
		memset(planes[0], 0x77, stride * height);
		break;
	}
}

static void fill_gradient_rgb32(const struct util_rgb_info *rgb,
				void *mem,
				unsigned int width, unsigned int height,
				unsigned int stride)
{
	unsigned int i, j;

	for (i = 0; i < height / 2; i++) {
		uint32_t *row = mem;

		for (j = 0; j < width / 2; j++) {
			uint32_t value = MAKE_RGBA10(rgb, j & 0x3ff, j & 0x3ff, j & 0x3ff, 0);
			row[2*j] = row[2*j+1] = cpu_to_le32(value);
		}
		mem += stride;
	}

	for (; i < height; i++) {
		uint32_t *row = mem;

		for (j = 0; j < width / 2; j++) {
			uint32_t value = MAKE_RGBA10(rgb, j & 0x3fc, j & 0x3fc, j & 0x3fc, 0);
			row[2*j] = row[2*j+1] = cpu_to_le32(value);
		}
		mem += stride;
	}
}

static void fill_gradient_rgb16fp(const struct util_rgb_info *rgb,
				  void *mem,
				  unsigned int width, unsigned int height,
				  unsigned int stride)
{
	unsigned int i, j;

	for (i = 0; i < height / 2; i++) {
		uint64_t *row = mem;

		for (j = 0; j < width / 2; j++) {
			uint64_t value = MAKE_RGBA10FP16(rgb, j & 0x3ff, j & 0x3ff, j & 0x3ff, 0);
			row[2*j] = row[2*j+1] = value;
		}
		mem += stride;
	}

	for (; i < height; i++) {
		uint64_t *row = mem;

		for (j = 0; j < width / 2; j++) {
			uint64_t value = MAKE_RGBA10FP16(rgb, j & 0x3fc, j & 0x3fc, j & 0x3fc, 0);
			row[2*j] = row[2*j+1] = value;
		}
		mem += stride;
	}
}

/* The gradient pattern creates two horizontal gray gradients, split
 * into two halves. The top half has 10bpc precision, the bottom half
 * has 8bpc precision. When using with a 10bpc fb format, there are 3
 * possible outcomes:
 *
 *  - Pixel data is encoded as 8bpc to the display, no dithering. This
 *    would lead to the top and bottom halves looking identical.
 *
 *  - Pixel data is encoded as 8bpc to the display, with dithering. This
 *    would lead to there being a visible difference between the two halves,
 *    but the top half would look a little speck-y due to the dithering.
 *
 *  - Pixel data is encoded at 10bpc+ to the display (which implies
 *    the display is able to show this level of depth). This should
 *    lead to the top half being a very clean gradient, and visibly different
 *    from the bottom half.
 *
 * Once we support additional fb formats, this approach could be extended
 * to distinguish even higher bpc precisions.
 *
 * Note that due to practical size considerations, for the screens
 * where this matters, the pattern actually emits stripes 2-pixels
 * wide for each gradient color. Otherwise the difference may be a bit
 * hard to notice.
 */
static void fill_gradient(const struct util_format_info *info, void *planes[3],
			  unsigned int width, unsigned int height,
			  unsigned int stride)
{
	switch (info->format) {
	case DRM_FORMAT_ARGB8888:
	case DRM_FORMAT_XRGB8888:
	case DRM_FORMAT_ABGR8888:
	case DRM_FORMAT_XBGR8888:
	case DRM_FORMAT_RGBA8888:
	case DRM_FORMAT_RGBX8888:
	case DRM_FORMAT_BGRA8888:
	case DRM_FORMAT_BGRX8888:
	case DRM_FORMAT_ARGB2101010:
	case DRM_FORMAT_XRGB2101010:
	case DRM_FORMAT_ABGR2101010:
	case DRM_FORMAT_XBGR2101010:
	case DRM_FORMAT_RGBA1010102:
	case DRM_FORMAT_RGBX1010102:
	case DRM_FORMAT_BGRA1010102:
	case DRM_FORMAT_BGRX1010102:
		return fill_gradient_rgb32(&info->rgb, planes[0],
					   width, height, stride);

	case DRM_FORMAT_XRGB16161616F:
	case DRM_FORMAT_XBGR16161616F:
	case DRM_FORMAT_ARGB16161616F:
	case DRM_FORMAT_ABGR16161616F:
		return fill_gradient_rgb16fp(&info->rgb, planes[0],
					     width, height, stride);
	}
}

/*
 * util_fill_pattern - Fill a buffer with a test pattern
 * @format: Pixel format
 * @pattern: Test pattern
 * @planes: Array of buffers
 * @width: Width in pixels
 * @height: Height in pixels
 * @stride: Line stride (pitch) in bytes
 *
 * Fill the buffers with the test pattern specified by the pattern parameter.
 * Supported formats vary depending on the selected pattern.
 */
void util_fill_pattern(uint32_t format, enum util_fill_pattern pattern,
		       void *planes[3], unsigned int width,
		       unsigned int height, unsigned int stride)
{
	const struct util_format_info *info;

	info = util_format_info_find(format);
	if (info == NULL)
		return;

	switch (pattern) {
	case UTIL_PATTERN_TILES:
		return fill_tiles(info, planes, width, height, stride);

	case UTIL_PATTERN_SMPTE:
		return fill_smpte(info, planes, width, height, stride);

	case UTIL_PATTERN_PLAIN:
		return fill_plain(info, planes, height, stride);

	case UTIL_PATTERN_GRADIENT:
		return fill_gradient(info, planes, width, height, stride);

	default:
		printf("Error: unsupported test pattern %u.\n", pattern);
		break;
	}
}

static const char *pattern_names[] = {
	[UTIL_PATTERN_TILES] = "tiles",
	[UTIL_PATTERN_SMPTE] = "smpte",
	[UTIL_PATTERN_PLAIN] = "plain",
	[UTIL_PATTERN_GRADIENT] = "gradient",
};

enum util_fill_pattern util_pattern_enum(const char *name)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(pattern_names); i++)
		if (!strcmp(pattern_names[i], name))
			return (enum util_fill_pattern)i;

	printf("Error: unsupported test pattern %s.\n", name);
	return UTIL_PATTERN_SMPTE;
}