edid.c 14 KB

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