drm_format_internal.h

  1/* SPDX-License-Identifier: GPL-2.0 or MIT */
  2
  3#ifndef DRM_FORMAT_INTERNAL_H
  4#define DRM_FORMAT_INTERNAL_H
  5
  6#include <linux/bits.h>
  7#include <linux/types.h>
  8#include <linux/swab.h>
  9
 10/*
 11 * Each pixel-format conversion helper takes a raw pixel in a
 12 * specific input format and returns a raw pixel in a specific
 13 * output format. All pixels are in little-endian byte order.
 14 *
 15 * Function names are
 16 *
 17 *   drm_pixel_<input>_to_<output>_<algorithm>()
 18 *
 19 * where <input> and <output> refer to pixel formats. The
 20 * <algorithm> is optional and hints to the method used for the
 21 * conversion. Helpers with no algorithm given apply pixel-bit
 22 * shifting.
 23 *
 24 * The argument type is u32. We expect this to be wide enough to
 25 * hold all conversion input from 32-bit RGB to any output format.
 26 * The Linux kernel should avoid format conversion for anything
 27 * but XRGB8888 input data. Converting from other format can still
 28 * be acceptable in some cases.
 29 *
 30 * The return type is u32. It is wide enough to hold all conversion
 31 * output from XRGB8888. For output formats wider than 32 bit, a
 32 * return type of u64 would be acceptable.
 33 */
 34
 35/*
 36 * Conversions from XRGB8888
 37 */
 38
 39static inline u32 drm_pixel_xrgb8888_to_r8_bt601(u32 pix)
 40{
 41	u32 r = (pix & 0x00ff0000) >> 16;
 42	u32 g = (pix & 0x0000ff00) >> 8;
 43	u32 b =  pix & 0x000000ff;
 44
 45	/* ITU-R BT.601: Y = 0.299 R + 0.587 G + 0.114 B */
 46	return (77 * r + 150 * g + 29 * b) / 256;
 47}
 48
 49static inline u32 drm_pixel_xrgb8888_to_rgb332(u32 pix)
 50{
 51	return ((pix & 0x00e00000) >> 16) |
 52	       ((pix & 0x0000e000) >> 11) |
 53	       ((pix & 0x000000c0) >> 6);
 54}
 55
 56static inline u32 drm_pixel_xrgb8888_to_rgb565(u32 pix)
 57{
 58	return ((pix & 0x00f80000) >> 8) |
 59	       ((pix & 0x0000fc00) >> 5) |
 60	       ((pix & 0x000000f8) >> 3);
 61}
 62
 63static inline u32 drm_pixel_xrgb8888_to_rgb565be(u32 pix)
 64{
 65	return swab16(drm_pixel_xrgb8888_to_rgb565(pix));
 66}
 67
 68static inline u32 drm_pixel_xrgb8888_to_rgbx5551(u32 pix)
 69{
 70	return ((pix & 0x00f80000) >> 8) |
 71	       ((pix & 0x0000f800) >> 5) |
 72	       ((pix & 0x000000f8) >> 2);
 73}
 74
 75static inline u32 drm_pixel_xrgb8888_to_rgba5551(u32 pix)
 76{
 77	return drm_pixel_xrgb8888_to_rgbx5551(pix) |
 78	       BIT(0); /* set alpha bit */
 79}
 80
 81static inline u32 drm_pixel_xrgb8888_to_xrgb1555(u32 pix)
 82{
 83	return ((pix & 0x00f80000) >> 9) |
 84	       ((pix & 0x0000f800) >> 6) |
 85	       ((pix & 0x000000f8) >> 3);
 86}
 87
 88static inline u32 drm_pixel_xrgb8888_to_argb1555(u32 pix)
 89{
 90	return BIT(15) | /* set alpha bit */
 91	       drm_pixel_xrgb8888_to_xrgb1555(pix);
 92}
 93
 94static inline u32 drm_pixel_xrgb8888_to_rgb888(u32 pix)
 95{
 96	return pix & GENMASK(23, 0);
 97}
 98
 99static inline u32 drm_pixel_xrgb8888_to_bgr888(u32 pix)
100{
101	return ((pix & 0x00ff0000) >> 16) |
102	       ((pix & 0x0000ff00)) |
103	       ((pix & 0x000000ff) << 16);
104}
105
106static inline u32 drm_pixel_xrgb8888_to_argb8888(u32 pix)
107{
108	return GENMASK(31, 24) | /* fill alpha bits */
109	       pix;
110}
111
112static inline u32 drm_pixel_xrgb8888_to_xbgr8888(u32 pix)
113{
114	return ((pix & 0xff000000)) | /* also copy filler bits */
115	       ((pix & 0x00ff0000) >> 16) |
116	       ((pix & 0x0000ff00)) |
117	       ((pix & 0x000000ff) << 16);
118}
119
120static inline u32 drm_pixel_xrgb8888_to_bgrx8888(u32 pix)
121{
122	return ((pix & 0xff000000) >> 24) | /* also copy filler bits */
123	       ((pix & 0x00ff0000) >> 8) |
124	       ((pix & 0x0000ff00) << 8) |
125	       ((pix & 0x000000ff) << 24);
126}
127
128static inline u32 drm_pixel_xrgb8888_to_abgr8888(u32 pix)
129{
130	return GENMASK(31, 24) | /* fill alpha bits */
131	       drm_pixel_xrgb8888_to_xbgr8888(pix);
132}
133
134static inline u32 drm_pixel_xrgb8888_to_xrgb2101010(u32 pix)
135{
136	pix = ((pix & 0x000000ff) << 2) |
137	      ((pix & 0x0000ff00) << 4) |
138	      ((pix & 0x00ff0000) << 6);
139	return pix | ((pix >> 8) & 0x00300c03);
140}
141
142static inline u32 drm_pixel_xrgb8888_to_argb2101010(u32 pix)
143{
144	return GENMASK(31, 30) | /* set alpha bits */
145	       drm_pixel_xrgb8888_to_xrgb2101010(pix);
146}
147
148static inline u32 drm_pixel_xrgb8888_to_xbgr2101010(u32 pix)
149{
150	pix = ((pix & 0x00ff0000) >> 14) |
151	      ((pix & 0x0000ff00) << 4) |
152	      ((pix & 0x000000ff) << 22);
153	return pix | ((pix >> 8) & 0x00300c03);
154}
155
156static inline u32 drm_pixel_xrgb8888_to_abgr2101010(u32 pix)
157{
158	return GENMASK(31, 30) | /* set alpha bits */
159	       drm_pixel_xrgb8888_to_xbgr2101010(pix);
160}
161
162/*
163 * Conversion from ARGB8888
164 */
165
166static inline u32 drm_pixel_argb8888_to_argb4444(u32 pix)
167{
168	return ((pix & 0xf0000000) >> 16) |
169	       ((pix & 0x00f00000) >> 12) |
170	       ((pix & 0x0000f000) >> 8) |
171	       ((pix & 0x000000f0) >> 4);
172}
173
174#endif