xref: /linux/drivers/gpu/drm/drm_format_internal.h (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
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 
drm_pixel_xrgb8888_to_r8_bt601(u32 pix)39 static 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 
drm_pixel_xrgb8888_to_rgb332(u32 pix)49 static 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 
drm_pixel_xrgb8888_to_rgb565(u32 pix)56 static 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 
drm_pixel_xrgb8888_to_rgb565be(u32 pix)63 static inline u32 drm_pixel_xrgb8888_to_rgb565be(u32 pix)
64 {
65 	return swab16(drm_pixel_xrgb8888_to_rgb565(pix));
66 }
67 
drm_pixel_xrgb8888_to_rgbx5551(u32 pix)68 static 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 
drm_pixel_xrgb8888_to_rgba5551(u32 pix)75 static 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 
drm_pixel_xrgb8888_to_xrgb1555(u32 pix)81 static 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 
drm_pixel_xrgb8888_to_argb1555(u32 pix)88 static 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 
drm_pixel_xrgb8888_to_rgb888(u32 pix)94 static inline u32 drm_pixel_xrgb8888_to_rgb888(u32 pix)
95 {
96 	return pix & GENMASK(23, 0);
97 }
98 
drm_pixel_xrgb8888_to_bgr888(u32 pix)99 static inline u32 drm_pixel_xrgb8888_to_bgr888(u32 pix)
100 {
101 	return ((pix & 0x00ff0000) >> 16) |
102 	       ((pix & 0x0000ff00)) |
103 	       ((pix & 0x000000ff) << 16);
104 }
105 
drm_pixel_xrgb8888_to_argb8888(u32 pix)106 static inline u32 drm_pixel_xrgb8888_to_argb8888(u32 pix)
107 {
108 	return GENMASK(31, 24) | /* fill alpha bits */
109 	       pix;
110 }
111 
drm_pixel_xrgb8888_to_xbgr8888(u32 pix)112 static 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 
drm_pixel_xrgb8888_to_bgrx8888(u32 pix)120 static 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 
drm_pixel_xrgb8888_to_abgr8888(u32 pix)128 static 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 
drm_pixel_xrgb8888_to_xrgb2101010(u32 pix)134 static 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 
drm_pixel_xrgb8888_to_argb2101010(u32 pix)142 static 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 
drm_pixel_xrgb8888_to_xbgr2101010(u32 pix)148 static 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 
drm_pixel_xrgb8888_to_abgr2101010(u32 pix)156 static 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 
drm_pixel_argb8888_to_argb4444(u32 pix)166 static 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
175