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