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 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 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 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 */ 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 */ 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 */ 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 } 170 171 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing, 172 int *panel_bits_per_colourp) 173 { 174 struct edid1_info *edid = (struct edid1_info *)buf; 175 bool timing_done; 176 int i; 177 178 if (buf_size < sizeof(*edid) || edid_check_info(edid)) { 179 debug("%s: Invalid buffer\n", __func__); 180 return -EINVAL; 181 } 182 183 if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) { 184 debug("%s: No preferred timing\n", __func__); 185 return -ENOENT; 186 } 187 188 /* Look for detailed timing */ 189 timing_done = false; 190 for (i = 0; i < 4; i++) { 191 struct edid_monitor_descriptor *desc; 192 193 desc = &edid->monitor_details.descriptor[i]; 194 if (desc->zero_flag_1 != 0) { 195 decode_timing((u8 *)desc, timing); 196 timing_done = true; 197 break; 198 } 199 } 200 if (!timing_done) 201 return -EINVAL; 202 203 if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) { 204 debug("%s: Not a digital display\n", __func__); 205 return -ENOSYS; 206 } 207 if (edid->version != 1 || edid->revision < 4) { 208 debug("%s: EDID version %d.%d does not have required info\n", 209 __func__, edid->version, edid->revision); 210 *panel_bits_per_colourp = -1; 211 } else { 212 *panel_bits_per_colourp = 213 ((edid->video_input_definition & 0x70) >> 3) + 4; 214 } 215 216 timing->hdmi_monitor = false; 217 if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) { 218 struct edid_cea861_info *info = 219 (struct edid_cea861_info *)(buf + sizeof(*edid)); 220 221 if (info->extension_tag == EDID_CEA861_EXTENSION_TAG) 222 timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info); 223 } 224 225 return 0; 226 } 227 228 /** 229 * Snip the tailing whitespace/return of a string. 230 * 231 * @param string The string to be snipped 232 * @return the snipped string 233 */ 234 static char *snip(char *string) 235 { 236 char *s; 237 238 /* 239 * This is always a 13 character buffer 240 * and it's not always terminated. 241 */ 242 string[12] = '\0'; 243 s = &string[strlen(string) - 1]; 244 245 while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' || 246 *s == '\0')) 247 *(s--) = '\0'; 248 249 return string; 250 } 251 252 /** 253 * Print an EDID monitor descriptor block 254 * 255 * @param monitor The EDID monitor descriptor block 256 * @have_timing Modifies to 1 if the desciptor contains timing info 257 */ 258 static void edid_print_dtd(struct edid_monitor_descriptor *monitor, 259 unsigned int *have_timing) 260 { 261 unsigned char *bytes = (unsigned char *)monitor; 262 struct edid_detailed_timing *timing = 263 (struct edid_detailed_timing *)monitor; 264 265 if (bytes[0] == 0 && bytes[1] == 0) { 266 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL) 267 printf("Monitor serial number: %s\n", 268 snip(monitor->data.string)); 269 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII) 270 printf("Monitor ID: %s\n", 271 snip(monitor->data.string)); 272 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME) 273 printf("Monitor name: %s\n", 274 snip(monitor->data.string)); 275 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE) 276 printf("Monitor range limits, horizontal sync: " 277 "%d-%d kHz, vertical refresh: " 278 "%d-%d Hz, max pixel clock: " 279 "%d MHz\n", 280 monitor->data.range_data.horizontal_min, 281 monitor->data.range_data.horizontal_max, 282 monitor->data.range_data.vertical_min, 283 monitor->data.range_data.vertical_max, 284 monitor->data.range_data.pixel_clock_max * 10); 285 } else { 286 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking; 287 uint32_t h_total, v_total, vfreq; 288 289 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing); 290 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing); 291 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing); 292 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing); 293 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing); 294 295 h_total = h_active + h_blanking; 296 v_total = v_active + v_blanking; 297 if (v_total > 0 && h_total > 0) 298 vfreq = pixclock / (v_total * h_total); 299 else 300 vfreq = 1; /* Error case */ 301 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active, 302 v_active, h_active > 1000 ? ' ' : '\t', vfreq); 303 *have_timing = 1; 304 } 305 } 306 307 /** 308 * Get the manufacturer name from an EDID info. 309 * 310 * @param edid_info The EDID info to be printed 311 * @param name Returns the string of the manufacturer name 312 */ 313 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name) 314 { 315 name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1; 316 name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1; 317 name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1; 318 name[3] = '\0'; 319 } 320 321 void edid_print_info(struct edid1_info *edid_info) 322 { 323 int i; 324 char manufacturer[4]; 325 unsigned int have_timing = 0; 326 uint32_t serial_number; 327 328 if (edid_check_info(edid_info)) { 329 printf("Not a valid EDID\n"); 330 return; 331 } 332 333 printf("EDID version: %d.%d\n", 334 edid_info->version, edid_info->revision); 335 336 printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info)); 337 338 edid_get_manufacturer_name(edid_info, manufacturer); 339 printf("Manufacturer: %s\n", manufacturer); 340 341 serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info); 342 if (serial_number != 0xffffffff) { 343 if (strcmp(manufacturer, "MAG") == 0) 344 serial_number -= 0x7000000; 345 if (strcmp(manufacturer, "OQI") == 0) 346 serial_number -= 456150000; 347 if (strcmp(manufacturer, "VSC") == 0) 348 serial_number -= 640000000; 349 } 350 printf("Serial number: %08x\n", serial_number); 351 printf("Manufactured in week: %d year: %d\n", 352 edid_info->week, edid_info->year + 1990); 353 354 printf("Video input definition: %svoltage level %d%s%s%s%s%s\n", 355 EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ? 356 "digital signal, " : "analog signal, ", 357 EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info), 358 EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ? 359 ", blank to black" : "", 360 EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ? 361 ", separate sync" : "", 362 EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ? 363 ", composite sync" : "", 364 EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ? 365 ", sync on green" : "", 366 EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ? 367 ", serration v" : ""); 368 369 printf("Monitor is %s\n", 370 EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB"); 371 372 printf("Maximum visible display size: %d cm x %d cm\n", 373 edid_info->max_size_horizontal, 374 edid_info->max_size_vertical); 375 376 printf("Power management features: %s%s, %s%s, %s%s\n", 377 EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ? 378 "" : "no ", "active off", 379 EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend", 380 EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby"); 381 382 printf("Estabilished timings:\n"); 383 if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info)) 384 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n"); 385 if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info)) 386 printf("\t720x400\t\t88 Hz (XGA2)\n"); 387 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info)) 388 printf("\t640x480\t\t60 Hz (VGA)\n"); 389 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info)) 390 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n"); 391 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info)) 392 printf("\t640x480\t\t72 Hz (VESA)\n"); 393 if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info)) 394 printf("\t640x480\t\t75 Hz (VESA)\n"); 395 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info)) 396 printf("\t800x600\t\t56 Hz (VESA)\n"); 397 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info)) 398 printf("\t800x600\t\t60 Hz (VESA)\n"); 399 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info)) 400 printf("\t800x600\t\t72 Hz (VESA)\n"); 401 if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info)) 402 printf("\t800x600\t\t75 Hz (VESA)\n"); 403 if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info)) 404 printf("\t832x624\t\t75 Hz (Mac II)\n"); 405 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info)) 406 printf("\t1024x768\t87 Hz Interlaced (8514A)\n"); 407 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info)) 408 printf("\t1024x768\t60 Hz (VESA)\n"); 409 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info)) 410 printf("\t1024x768\t70 Hz (VESA)\n"); 411 if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info)) 412 printf("\t1024x768\t75 Hz (VESA)\n"); 413 if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info)) 414 printf("\t1280x1024\t75 (VESA)\n"); 415 if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info)) 416 printf("\t1152x870\t75 (Mac II)\n"); 417 418 /* Standard timings. */ 419 printf("Standard timings:\n"); 420 for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) { 421 unsigned int aspect = 10000; 422 unsigned int x, y; 423 unsigned char xres, vfreq; 424 425 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i); 426 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i); 427 if ((xres != vfreq) || 428 ((xres != 0) && (xres != 1)) || 429 ((vfreq != 0) && (vfreq != 1))) { 430 switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info, 431 i)) { 432 case ASPECT_625: 433 aspect = 6250; 434 break; 435 case ASPECT_75: 436 aspect = 7500; 437 break; 438 case ASPECT_8: 439 aspect = 8000; 440 break; 441 case ASPECT_5625: 442 aspect = 5625; 443 break; 444 } 445 x = (xres + 31) * 8; 446 y = x * aspect / 10000; 447 printf("\t%dx%d%c\t%d Hz\n", x, y, 448 x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60); 449 have_timing = 1; 450 } 451 } 452 453 /* Detailed timing information. */ 454 for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor); 455 i++) { 456 edid_print_dtd(&edid_info->monitor_details.descriptor[i], 457 &have_timing); 458 } 459 460 if (!have_timing) 461 printf("\tNone\n"); 462 } 463