xref: /openbmc/u-boot/include/edid.h (revision 0642f485)
1 /*
2  * Copyright (c) 2012 The Chromium OS Authors.
3  *
4  * (C) Copyright 2010
5  * Petr Stetiar <ynezz@true.cz>
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  *
9  * Contains stolen code from ddcprobe project which is:
10  * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
11  */
12 
13 #ifndef __EDID_H_
14 #define __EDID_H_
15 
16 #include <linux/types.h>
17 
18 /* Size of the EDID data */
19 #define EDID_SIZE	128
20 #define EDID_EXT_SIZE	256
21 
22 #define GET_BIT(_x, _pos) \
23 	(((_x) >> (_pos)) & 1)
24 #define GET_BITS(_x, _pos_msb, _pos_lsb) \
25 	(((_x) >> (_pos_lsb)) & ((1 << ((_pos_msb) - (_pos_lsb) + 1)) - 1))
26 
27 /* Aspect ratios used in EDID info. */
28 enum edid_aspect {
29 	ASPECT_625 = 0,
30 	ASPECT_75,
31 	ASPECT_8,
32 	ASPECT_5625,
33 };
34 
35 /* Detailed timing information used in EDID v1.x */
36 struct edid_detailed_timing {
37 	unsigned char pixel_clock[2];
38 #define EDID_DETAILED_TIMING_PIXEL_CLOCK(_x) \
39 	(((((uint32_t)(_x).pixel_clock[1]) << 8) + \
40 	 (_x).pixel_clock[0]) * 10000)
41 	unsigned char horizontal_active;
42 	unsigned char horizontal_blanking;
43 	unsigned char horizontal_active_blanking_hi;
44 #define EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(_x) \
45 	((GET_BITS((_x).horizontal_active_blanking_hi, 7, 4) << 8) + \
46 	 (_x).horizontal_active)
47 #define EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(_x) \
48 	((GET_BITS((_x).horizontal_active_blanking_hi, 3, 0) << 8) + \
49 	 (_x).horizontal_blanking)
50 	unsigned char vertical_active;
51 	unsigned char vertical_blanking;
52 	unsigned char vertical_active_blanking_hi;
53 #define EDID_DETAILED_TIMING_VERTICAL_ACTIVE(_x) \
54 	((GET_BITS((_x).vertical_active_blanking_hi, 7, 4) << 8) + \
55 	 (_x).vertical_active)
56 #define EDID_DETAILED_TIMING_VERTICAL_BLANKING(_x) \
57 	((GET_BITS((_x).vertical_active_blanking_hi, 3, 0) << 8) + \
58 	 (_x).vertical_blanking)
59 	unsigned char hsync_offset;
60 	unsigned char hsync_pulse_width;
61 	unsigned char vsync_offset_pulse_width;
62 	unsigned char hsync_vsync_offset_pulse_width_hi;
63 #define EDID_DETAILED_TIMING_HSYNC_OFFSET(_x) \
64 	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 7, 6) << 8) + \
65 	 (_x).hsync_offset)
66 #define EDID_DETAILED_TIMING_HSYNC_PULSE_WIDTH(_x) \
67 	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 5, 4) << 8) + \
68 	 (_x).hsync_pulse_width)
69 #define EDID_DETAILED_TIMING_VSYNC_OFFSET(_x) \
70 	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 3, 2) << 4) + \
71 	 GET_BITS((_x).vsync_offset_pulse_width, 7, 4))
72 #define EDID_DETAILED_TIMING_VSYNC_PULSE_WIDTH(_x) \
73 	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 1, 0) << 4) + \
74 	 GET_BITS((_x).vsync_offset_pulse_width, 3, 0))
75 	unsigned char himage_size;
76 	unsigned char vimage_size;
77 	unsigned char himage_vimage_size_hi;
78 #define EDID_DETAILED_TIMING_HIMAGE_SIZE(_x) \
79 	((GET_BITS((_x).himage_vimage_size_hi, 7, 4) << 8) + (_x).himage_size)
80 #define EDID_DETAILED_TIMING_VIMAGE_SIZE(_x) \
81 	((GET_BITS((_x).himage_vimage_size_hi, 3, 0) << 8) + (_x).vimage_size)
82 	unsigned char hborder;
83 	unsigned char vborder;
84 	unsigned char flags;
85 #define EDID_DETAILED_TIMING_FLAG_INTERLACED(_x) \
86 	GET_BIT((_x).flags, 7)
87 #define EDID_DETAILED_TIMING_FLAG_STEREO(_x) \
88 	GET_BITS((_x).flags, 6, 5)
89 #define EDID_DETAILED_TIMING_FLAG_DIGITAL_COMPOSITE(_x) \
90 	GET_BITS((_x).flags, 4, 3)
91 #define EDID_DETAILED_TIMING_FLAG_POLARITY(_x) \
92 	GET_BITS((_x).flags, 2, 1)
93 #define EDID_DETAILED_TIMING_FLAG_VSYNC_POLARITY(_x) \
94 	GET_BIT((_x).flags, 2)
95 #define EDID_DETAILED_TIMING_FLAG_HSYNC_POLARITY(_x) \
96 	GET_BIT((_x).flags, 1)
97 #define EDID_DETAILED_TIMING_FLAG_INTERLEAVED(_x) \
98 	GET_BIT((_x).flags, 0)
99 } __attribute__ ((__packed__));
100 
101 enum edid_monitor_descriptor_types {
102 	EDID_MONITOR_DESCRIPTOR_SERIAL = 0xff,
103 	EDID_MONITOR_DESCRIPTOR_ASCII = 0xfe,
104 	EDID_MONITOR_DESCRIPTOR_RANGE = 0xfd,
105 	EDID_MONITOR_DESCRIPTOR_NAME = 0xfc,
106 };
107 
108 struct edid_monitor_descriptor {
109 	uint16_t zero_flag_1;
110 	unsigned char zero_flag_2;
111 	unsigned char type;
112 	unsigned char zero_flag_3;
113 	union {
114 		char string[13];
115 		struct {
116 			unsigned char vertical_min;
117 			unsigned char vertical_max;
118 			unsigned char horizontal_min;
119 			unsigned char horizontal_max;
120 			unsigned char pixel_clock_max;
121 			unsigned char gtf_data[8];
122 		} range_data;
123 	} data;
124 } __attribute__ ((__packed__));
125 
126 struct edid1_info {
127 	unsigned char header[8];
128 	unsigned char manufacturer_name[2];
129 #define EDID1_INFO_MANUFACTURER_NAME_ZERO(_x) \
130 	GET_BIT(((_x).manufacturer_name[0]), 7)
131 #define EDID1_INFO_MANUFACTURER_NAME_CHAR1(_x) \
132 	GET_BITS(((_x).manufacturer_name[0]), 6, 2)
133 #define EDID1_INFO_MANUFACTURER_NAME_CHAR2(_x) \
134 	((GET_BITS(((_x).manufacturer_name[0]), 1, 0) << 3) + \
135 	 GET_BITS(((_x).manufacturer_name[1]), 7, 5))
136 #define EDID1_INFO_MANUFACTURER_NAME_CHAR3(_x) \
137 	GET_BITS(((_x).manufacturer_name[1]), 4, 0)
138 	unsigned char product_code[2];
139 #define EDID1_INFO_PRODUCT_CODE(_x) \
140 	(((uint16_t)(_x).product_code[1] << 8) + (_x).product_code[0])
141 	unsigned char serial_number[4];
142 #define EDID1_INFO_SERIAL_NUMBER(_x) \
143 	(((uint32_t)(_x).serial_number[3] << 24) + \
144 	 ((_x).serial_number[2] << 16) + ((_x).serial_number[1] << 8) + \
145 	 (_x).serial_number[0])
146 	unsigned char week;
147 	unsigned char year;
148 	unsigned char version;
149 	unsigned char revision;
150 	unsigned char video_input_definition;
151 #define EDID1_INFO_VIDEO_INPUT_DIGITAL(_x) \
152 	GET_BIT(((_x).video_input_definition), 7)
153 #define EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(_x) \
154 	GET_BITS(((_x).video_input_definition), 6, 5)
155 #define EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(_x) \
156 	GET_BIT(((_x).video_input_definition), 4)
157 #define EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(_x) \
158 	GET_BIT(((_x).video_input_definition), 3)
159 #define EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(_x) \
160 	GET_BIT(((_x).video_input_definition), 2)
161 #define EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(_x) \
162 	GET_BIT(((_x).video_input_definition), 1)
163 #define EDID1_INFO_VIDEO_INPUT_SERRATION_V(_x) \
164 	GET_BIT(((_x).video_input_definition), 0)
165 	unsigned char max_size_horizontal;
166 	unsigned char max_size_vertical;
167 	unsigned char gamma;
168 	unsigned char feature_support;
169 #define EDID1_INFO_FEATURE_STANDBY(_x) \
170 	GET_BIT(((_x).feature_support), 7)
171 #define EDID1_INFO_FEATURE_SUSPEND(_x) \
172 	GET_BIT(((_x).feature_support), 6)
173 #define EDID1_INFO_FEATURE_ACTIVE_OFF(_x) \
174 	GET_BIT(((_x).feature_support), 5)
175 #define EDID1_INFO_FEATURE_DISPLAY_TYPE(_x) \
176 	GET_BITS(((_x).feature_support), 4, 3)
177 #define EDID1_INFO_FEATURE_RGB(_x) \
178 	GET_BIT(((_x).feature_support), 2)
179 #define EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(_x) \
180 	GET_BIT(((_x).feature_support), 1)
181 #define EDID1_INFO_FEATURE_DEFAULT_GTF_SUPPORT(_x) \
182 	GET_BIT(((_x).feature_support), 0)
183 	unsigned char color_characteristics[10];
184 	unsigned char established_timings[3];
185 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_70(_x) \
186 	GET_BIT(((_x).established_timings[0]), 7)
187 #define EDID1_INFO_ESTABLISHED_TIMING_720X400_88(_x) \
188 	GET_BIT(((_x).established_timings[0]), 6)
189 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_60(_x) \
190 	GET_BIT(((_x).established_timings[0]), 5)
191 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_67(_x) \
192 	GET_BIT(((_x).established_timings[0]), 4)
193 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_72(_x) \
194 	GET_BIT(((_x).established_timings[0]), 3)
195 #define EDID1_INFO_ESTABLISHED_TIMING_640X480_75(_x) \
196 	GET_BIT(((_x).established_timings[0]), 2)
197 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_56(_x) \
198 	GET_BIT(((_x).established_timings[0]), 1)
199 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_60(_x) \
200 	GET_BIT(((_x).established_timings[0]), 0)
201 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_72(_x) \
202 	GET_BIT(((_x).established_timings[1]), 7)
203 #define EDID1_INFO_ESTABLISHED_TIMING_800X600_75(_x) \
204 	GET_BIT(((_x).established_timings[1]), 6)
205 #define EDID1_INFO_ESTABLISHED_TIMING_832X624_75(_x) \
206 	GET_BIT(((_x).established_timings[1]), 5)
207 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(_x) \
208 	GET_BIT(((_x).established_timings[1]), 4)
209 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(_x) \
210 	GET_BIT(((_x).established_timings[1]), 3)
211 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(_x) \
212 	GET_BIT(((_x).established_timings[1]), 2)
213 #define EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(_x) \
214 	GET_BIT(((_x).established_timings[1]), 1)
215 #define EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(_x) \
216 	GET_BIT(((_x).established_timings[1]), 0)
217 #define EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(_x) \
218 	GET_BIT(((_x).established_timings[2]), 7)
219 	struct {
220 		unsigned char xresolution;
221 		unsigned char aspect_vfreq;
222 	} __attribute__((__packed__)) standard_timings[8];
223 #define EDID1_INFO_STANDARD_TIMING_XRESOLUTION(_x, _i) \
224 	(((_x).standard_timings[_i]).xresolution)
225 #define EDID1_INFO_STANDARD_TIMING_ASPECT(_x, _i) \
226 	GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 7, 6)
227 #define EDID1_INFO_STANDARD_TIMING_VFREQ(_x, _i) \
228 	GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 5, 0)
229 	union {
230 		unsigned char timing[72];
231 		struct edid_monitor_descriptor descriptor[4];
232 	} monitor_details;
233 	unsigned char extension_flag;
234 	unsigned char checksum;
235 } __attribute__ ((__packed__));
236 
237 struct edid_cea861_info {
238 	unsigned char extension_tag;
239 #define EDID_CEA861_EXTENSION_TAG	0x02
240 	unsigned char revision;
241 	unsigned char dtd_offset;
242 	unsigned char dtd_count;
243 #define EDID_CEA861_SUPPORTS_UNDERSCAN(_x) \
244 	GET_BIT(((_x).dtd_count), 7)
245 #define EDID_CEA861_SUPPORTS_BASIC_AUDIO(_x) \
246 	GET_BIT(((_x).dtd_count), 6)
247 #define EDID_CEA861_SUPPORTS_YUV444(_x) \
248 	GET_BIT(((_x).dtd_count), 5)
249 #define EDID_CEA861_SUPPORTS_YUV422(_x) \
250 	GET_BIT(((_x).dtd_count), 4)
251 #define EDID_CEA861_DTD_COUNT(_x) \
252 	GET_BITS(((_x).dtd_count), 3, 0)
253 	unsigned char data[124];
254 } __attribute__ ((__packed__));
255 
256 /**
257  * Print the EDID info.
258  *
259  * @param edid_info	The EDID info to be printed
260  */
261 void edid_print_info(struct edid1_info *edid_info);
262 
263 /**
264  * Check the EDID info.
265  *
266  * @param info  The EDID info to be checked
267  * @return 0 on valid, or -1 on invalid
268  */
269 int edid_check_info(struct edid1_info *info);
270 
271 /**
272  * Check checksum of a 128 bytes EDID data block
273  *
274  * @param edid_block	EDID block data
275  *
276  * @return 0 on success, or a negative errno on error
277  */
278 int edid_check_checksum(u8 *edid_block);
279 
280 /**
281  * Get the horizontal and vertical rate ranges of the monitor.
282  *
283  * @param edid	The EDID info
284  * @param hmin	Returns the minimum horizontal rate
285  * @param hmax	Returns the maxium horizontal rate
286  * @param vmin	Returns the minimum vertical rate
287  * @param vmax	Returns the maxium vertical rate
288  * @return 0 on success, or -1 on error
289  */
290 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
291 		    unsigned int *hmax, unsigned int *vmin,
292 		    unsigned int *vmax);
293 
294 struct display_timing;
295 
296 /**
297  * edid_get_timing() - Get basic digital display parameters
298  *
299  * @param buf		Buffer containing EDID data
300  * @param buf_size	Size of buffer in bytes
301  * @param timing	Place to put preferring timing information
302  * @param panel_bits_per_colourp	Place to put the number of bits per
303  *			colour supported by the panel. This will be set to
304  *			-1 if not available
305  * @return 0 if timings are OK, -ve on error
306  */
307 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
308 		    int *panel_bits_per_colourp);
309 
310 #endif /* __EDID_H_ */
311