1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2012 The Chromium OS Authors.
4 *
5 * (C) Copyright 2010
6 * Petr Stetiar <ynezz@true.cz>
7 *
8 * Contains stolen code from ddcprobe project which is:
9 * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
10 */
11
12 #include <common.h>
13 #include <edid.h>
14 #include <errno.h>
15 #include <fdtdec.h>
16 #include <log.h>
17 #include <linux/ctype.h>
18 #include <linux/string.h>
19
edid_check_info(struct edid1_info * edid_info)20 int edid_check_info(struct edid1_info *edid_info)
21 {
22 if ((edid_info == NULL) || (edid_info->version == 0))
23 return -1;
24
25 if (memcmp(edid_info->header, "\x0\xff\xff\xff\xff\xff\xff\x0", 8))
26 return -1;
27
28 if (edid_info->version == 0xff && edid_info->revision == 0xff)
29 return -1;
30
31 return 0;
32 }
33
edid_check_checksum(u8 * edid_block)34 int edid_check_checksum(u8 *edid_block)
35 {
36 u8 checksum = 0;
37 int i;
38
39 for (i = 0; i < 128; i++)
40 checksum += edid_block[i];
41
42 return (checksum == 0) ? 0 : -EINVAL;
43 }
44
edid_get_ranges(struct edid1_info * edid,unsigned int * hmin,unsigned int * hmax,unsigned int * vmin,unsigned int * vmax)45 int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
46 unsigned int *hmax, unsigned int *vmin,
47 unsigned int *vmax)
48 {
49 int i;
50 struct edid_monitor_descriptor *monitor;
51
52 *hmin = *hmax = *vmin = *vmax = 0;
53 if (edid_check_info(edid))
54 return -1;
55
56 for (i = 0; i < ARRAY_SIZE(edid->monitor_details.descriptor); i++) {
57 monitor = &edid->monitor_details.descriptor[i];
58 if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE) {
59 *hmin = monitor->data.range_data.horizontal_min;
60 *hmax = monitor->data.range_data.horizontal_max;
61 *vmin = monitor->data.range_data.vertical_min;
62 *vmax = monitor->data.range_data.vertical_max;
63 return 0;
64 }
65 }
66 return -1;
67 }
68
69 /* Set all parts of a timing entry to the same value */
set_entry(struct timing_entry * entry,u32 value)70 static void set_entry(struct timing_entry *entry, u32 value)
71 {
72 entry->min = value;
73 entry->typ = value;
74 entry->max = value;
75 }
76
77 /**
78 * decode_timing() - Decoding an 18-byte detailed timing record
79 *
80 * @buf: Pointer to EDID detailed timing record
81 * @timing: Place to put timing
82 */
decode_timing(u8 * buf,struct display_timing * timing)83 static void decode_timing(u8 *buf, struct display_timing *timing)
84 {
85 uint x_mm, y_mm;
86 unsigned int ha, hbl, hso, hspw, hborder;
87 unsigned int va, vbl, vso, vspw, vborder;
88 struct edid_detailed_timing *t = (struct edid_detailed_timing *)buf;
89
90 /* Edid contains pixel clock in terms of 10KHz */
91 set_entry(&timing->pixelclock, (buf[0] + (buf[1] << 8)) * 10000);
92 x_mm = (buf[12] + ((buf[14] & 0xf0) << 4));
93 y_mm = (buf[13] + ((buf[14] & 0x0f) << 8));
94 ha = (buf[2] + ((buf[4] & 0xf0) << 4));
95 hbl = (buf[3] + ((buf[4] & 0x0f) << 8));
96 hso = (buf[8] + ((buf[11] & 0xc0) << 2));
97 hspw = (buf[9] + ((buf[11] & 0x30) << 4));
98 hborder = buf[15];
99 va = (buf[5] + ((buf[7] & 0xf0) << 4));
100 vbl = (buf[6] + ((buf[7] & 0x0f) << 8));
101 vso = ((buf[10] >> 4) + ((buf[11] & 0x0c) << 2));
102 vspw = ((buf[10] & 0x0f) + ((buf[11] & 0x03) << 4));
103 vborder = buf[16];
104
105 set_entry(&timing->hactive, ha);
106 set_entry(&timing->hfront_porch, hso);
107 set_entry(&timing->hback_porch, hbl - hso - hspw);
108 set_entry(&timing->hsync_len, hspw);
109
110 set_entry(&timing->vactive, va);
111 set_entry(&timing->vfront_porch, vso);
112 set_entry(&timing->vback_porch, vbl - vso - vspw);
113 set_entry(&timing->vsync_len, vspw);
114
115 timing->flags = 0;
116 if (EDID_DETAILED_TIMING_FLAG_HSYNC_POLARITY(*t))
117 timing->flags |= DISPLAY_FLAGS_HSYNC_HIGH;
118 else
119 timing->flags |= DISPLAY_FLAGS_HSYNC_LOW;
120 if (EDID_DETAILED_TIMING_FLAG_VSYNC_POLARITY(*t))
121 timing->flags |= DISPLAY_FLAGS_VSYNC_HIGH;
122 else
123 timing->flags |= DISPLAY_FLAGS_VSYNC_LOW;
124
125 if (EDID_DETAILED_TIMING_FLAG_INTERLACED(*t))
126 timing->flags = DISPLAY_FLAGS_INTERLACED;
127
128 debug("Detailed mode clock %u Hz, %d mm x %d mm\n"
129 " %04x %04x %04x %04x hborder %x\n"
130 " %04x %04x %04x %04x vborder %x\n",
131 timing->pixelclock.typ,
132 x_mm, y_mm,
133 ha, ha + hso, ha + hso + hspw,
134 ha + hbl, hborder,
135 va, va + vso, va + vso + vspw,
136 va + vbl, vborder);
137 }
138
139 /**
140 * Check if HDMI vendor specific data block is present in CEA block
141 * @param info CEA extension block
142 * @return true if block is found
143 */
cea_is_hdmi_vsdb_present(struct edid_cea861_info * info)144 static bool cea_is_hdmi_vsdb_present(struct edid_cea861_info *info)
145 {
146 u8 end, i = 0;
147
148 /* check for end of data block */
149 end = info->dtd_offset;
150 if (end == 0)
151 end = sizeof(info->data);
152 if (end < 4 || end > sizeof(info->data))
153 return false;
154 end -= 4;
155
156 while (i < end) {
157 /* Look for vendor specific data block of appropriate size */
158 if ((EDID_CEA861_DB_TYPE(*info, i) == EDID_CEA861_DB_VENDOR) &&
159 (EDID_CEA861_DB_LEN(*info, i) >= 5)) {
160 u8 *db = &info->data[i + 1];
161 u32 oui = db[0] | (db[1] << 8) | (db[2] << 16);
162
163 if (oui == HDMI_IEEE_OUI)
164 return true;
165 }
166 i += EDID_CEA861_DB_LEN(*info, i) + 1;
167 }
168
169 return false;
170 }
171
edid_get_timing_validate(u8 * buf,int buf_size,struct display_timing * timing,int * panel_bits_per_colourp,bool (* mode_valid)(void * priv,const struct display_timing * timing),void * mode_valid_priv)172 int edid_get_timing_validate(u8 *buf, int buf_size,
173 struct display_timing *timing,
174 int *panel_bits_per_colourp,
175 bool (*mode_valid)(void *priv,
176 const struct display_timing *timing),
177 void *mode_valid_priv)
178 {
179 struct edid1_info *edid = (struct edid1_info *)buf;
180 bool timing_done;
181 int i;
182
183 if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
184 debug("%s: Invalid buffer\n", __func__);
185 return -EINVAL;
186 }
187
188 if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
189 debug("%s: No preferred timing\n", __func__);
190 return -ENOENT;
191 }
192
193 /* Look for detailed timing */
194 timing_done = false;
195 for (i = 0; i < 4; i++) {
196 struct edid_monitor_descriptor *desc;
197
198 desc = &edid->monitor_details.descriptor[i];
199 if (desc->zero_flag_1 != 0) {
200 decode_timing((u8 *)desc, timing);
201 if (mode_valid)
202 timing_done = mode_valid(mode_valid_priv,
203 timing);
204 else
205 timing_done = true;
206
207 if (timing_done)
208 break;
209 }
210 }
211 if (!timing_done)
212 return -EINVAL;
213
214 if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
215 debug("%s: Not a digital display\n", __func__);
216 return -ENOSYS;
217 }
218 if (edid->version != 1 || edid->revision < 4) {
219 debug("%s: EDID version %d.%d does not have required info\n",
220 __func__, edid->version, edid->revision);
221 *panel_bits_per_colourp = -1;
222 } else {
223 *panel_bits_per_colourp =
224 ((edid->video_input_definition & 0x70) >> 3) + 4;
225 }
226
227 timing->hdmi_monitor = false;
228 if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) {
229 struct edid_cea861_info *info =
230 (struct edid_cea861_info *)(buf + sizeof(*edid));
231
232 if (info->extension_tag == EDID_CEA861_EXTENSION_TAG)
233 timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info);
234 }
235
236 return 0;
237 }
238
edid_get_timing(u8 * buf,int buf_size,struct display_timing * timing,int * panel_bits_per_colourp)239 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
240 int *panel_bits_per_colourp)
241 {
242 return edid_get_timing_validate(buf, buf_size, timing,
243 panel_bits_per_colourp, NULL, NULL);
244 }
245
246
247 /**
248 * Snip the tailing whitespace/return of a string.
249 *
250 * @param string The string to be snipped
251 * @return the snipped string
252 */
snip(char * string)253 static char *snip(char *string)
254 {
255 char *s;
256
257 /*
258 * This is always a 13 character buffer
259 * and it's not always terminated.
260 */
261 string[12] = '\0';
262 s = &string[strlen(string) - 1];
263
264 while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
265 *s == '\0'))
266 *(s--) = '\0';
267
268 return string;
269 }
270
271 /**
272 * Print an EDID monitor descriptor block
273 *
274 * @param monitor The EDID monitor descriptor block
275 * @have_timing Modifies to 1 if the desciptor contains timing info
276 */
edid_print_dtd(struct edid_monitor_descriptor * monitor,unsigned int * have_timing)277 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
278 unsigned int *have_timing)
279 {
280 unsigned char *bytes = (unsigned char *)monitor;
281 struct edid_detailed_timing *timing =
282 (struct edid_detailed_timing *)monitor;
283
284 if (bytes[0] == 0 && bytes[1] == 0) {
285 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
286 printf("Monitor serial number: %s\n",
287 snip(monitor->data.string));
288 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
289 printf("Monitor ID: %s\n",
290 snip(monitor->data.string));
291 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
292 printf("Monitor name: %s\n",
293 snip(monitor->data.string));
294 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
295 printf("Monitor range limits, horizontal sync: "
296 "%d-%d kHz, vertical refresh: "
297 "%d-%d Hz, max pixel clock: "
298 "%d MHz\n",
299 monitor->data.range_data.horizontal_min,
300 monitor->data.range_data.horizontal_max,
301 monitor->data.range_data.vertical_min,
302 monitor->data.range_data.vertical_max,
303 monitor->data.range_data.pixel_clock_max * 10);
304 } else {
305 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
306 uint32_t h_total, v_total, vfreq;
307
308 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
309 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
310 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
311 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
312 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
313
314 h_total = h_active + h_blanking;
315 v_total = v_active + v_blanking;
316 if (v_total > 0 && h_total > 0)
317 vfreq = pixclock / (v_total * h_total);
318 else
319 vfreq = 1; /* Error case */
320 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
321 v_active, h_active > 1000 ? ' ' : '\t', vfreq);
322 *have_timing = 1;
323 }
324 }
325
326 /**
327 * Get the manufacturer name from an EDID info.
328 *
329 * @param edid_info The EDID info to be printed
330 * @param name Returns the string of the manufacturer name
331 */
edid_get_manufacturer_name(struct edid1_info * edid,char * name)332 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
333 {
334 name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
335 name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
336 name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
337 name[3] = '\0';
338 }
339
edid_print_info(struct edid1_info * edid_info)340 void edid_print_info(struct edid1_info *edid_info)
341 {
342 int i;
343 char manufacturer[4];
344 unsigned int have_timing = 0;
345 uint32_t serial_number;
346
347 if (edid_check_info(edid_info)) {
348 printf("Not a valid EDID\n");
349 return;
350 }
351
352 printf("EDID version: %d.%d\n",
353 edid_info->version, edid_info->revision);
354
355 printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
356
357 edid_get_manufacturer_name(edid_info, manufacturer);
358 printf("Manufacturer: %s\n", manufacturer);
359
360 serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
361 if (serial_number != 0xffffffff) {
362 if (strcmp(manufacturer, "MAG") == 0)
363 serial_number -= 0x7000000;
364 if (strcmp(manufacturer, "OQI") == 0)
365 serial_number -= 456150000;
366 if (strcmp(manufacturer, "VSC") == 0)
367 serial_number -= 640000000;
368 }
369 printf("Serial number: %08x\n", serial_number);
370 printf("Manufactured in week: %d year: %d\n",
371 edid_info->week, edid_info->year + 1990);
372
373 printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
374 EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
375 "digital signal, " : "analog signal, ",
376 EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
377 EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
378 ", blank to black" : "",
379 EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
380 ", separate sync" : "",
381 EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
382 ", composite sync" : "",
383 EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
384 ", sync on green" : "",
385 EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
386 ", serration v" : "");
387
388 printf("Monitor is %s\n",
389 EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
390
391 printf("Maximum visible display size: %d cm x %d cm\n",
392 edid_info->max_size_horizontal,
393 edid_info->max_size_vertical);
394
395 printf("Power management features: %s%s, %s%s, %s%s\n",
396 EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
397 "" : "no ", "active off",
398 EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
399 EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
400
401 printf("Estabilished timings:\n");
402 if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
403 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
404 if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
405 printf("\t720x400\t\t88 Hz (XGA2)\n");
406 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
407 printf("\t640x480\t\t60 Hz (VGA)\n");
408 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
409 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
410 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
411 printf("\t640x480\t\t72 Hz (VESA)\n");
412 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
413 printf("\t640x480\t\t75 Hz (VESA)\n");
414 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
415 printf("\t800x600\t\t56 Hz (VESA)\n");
416 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
417 printf("\t800x600\t\t60 Hz (VESA)\n");
418 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
419 printf("\t800x600\t\t72 Hz (VESA)\n");
420 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
421 printf("\t800x600\t\t75 Hz (VESA)\n");
422 if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
423 printf("\t832x624\t\t75 Hz (Mac II)\n");
424 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
425 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
426 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
427 printf("\t1024x768\t60 Hz (VESA)\n");
428 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
429 printf("\t1024x768\t70 Hz (VESA)\n");
430 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
431 printf("\t1024x768\t75 Hz (VESA)\n");
432 if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
433 printf("\t1280x1024\t75 (VESA)\n");
434 if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
435 printf("\t1152x870\t75 (Mac II)\n");
436
437 /* Standard timings. */
438 printf("Standard timings:\n");
439 for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
440 unsigned int aspect = 10000;
441 unsigned int x, y;
442 unsigned char xres, vfreq;
443
444 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
445 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
446 if ((xres != vfreq) ||
447 ((xres != 0) && (xres != 1)) ||
448 ((vfreq != 0) && (vfreq != 1))) {
449 switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
450 i)) {
451 case ASPECT_625:
452 aspect = 6250;
453 break;
454 case ASPECT_75:
455 aspect = 7500;
456 break;
457 case ASPECT_8:
458 aspect = 8000;
459 break;
460 case ASPECT_5625:
461 aspect = 5625;
462 break;
463 }
464 x = (xres + 31) * 8;
465 y = x * aspect / 10000;
466 printf("\t%dx%d%c\t%d Hz\n", x, y,
467 x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
468 have_timing = 1;
469 }
470 }
471
472 /* Detailed timing information. */
473 for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
474 i++) {
475 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
476 &have_timing);
477 }
478
479 if (!have_timing)
480 printf("\tNone\n");
481 }
482