common/edid.c

   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
  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
  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
  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 */
  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  */
  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  */
 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
 172 static bool edid_find_valid_timing(void *buf, int count,
 173                                    struct display_timing *timing,
 174                                    bool (*mode_valid)(void *priv,
 175                                         const struct display_timing *timing),
 176                                    void *mode_valid_priv)
 177 {
 178         struct edid_detailed_timing *t = buf;
 179         bool found = false;
 180         int i;
 181
 182         for (i = 0; i < count && !found; i++, t++)
 183                 if (EDID_DETAILED_TIMING_PIXEL_CLOCK(*t) != 0) {
 184                         decode_timing((u8 *)t, timing);
 185                         if (mode_valid)
 186                                 found = mode_valid(mode_valid_priv,
 187                                                    timing);
 188                         else
 189                                 found = true;
 190                 }
 191
 192         return found;
 193 }
 194
 195 int edid_get_timing_validate(u8 *buf, int buf_size,
 196                              struct display_timing *timing,
 197                              int *panel_bits_per_colourp,
 198                              bool (*mode_valid)(void *priv,
 199                                         const struct display_timing *timing),
 200                              void *mode_valid_priv)
 201 {
 202         struct edid1_info *edid = (struct edid1_info *)buf;
 203         bool found;
 204
 205         if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
 206                 debug("%s: Invalid buffer\n", __func__);
 207                 return -EINVAL;
 208         }
 209
 210         if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
 211                 debug("%s: Not a digital display\n", __func__);
 212                 return -ENOSYS;
 213         }
 214
 215         if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
 216                 debug("%s: No preferred timing\n", __func__);
 217                 return -ENOENT;
 218         }
 219
 220         /* Look for detailed timing in base EDID */
 221         found = edid_find_valid_timing(edid->monitor_details.descriptor, 4,
 222                                        timing, mode_valid, mode_valid_priv);
 223
 224         /* Look for detailed timing in CTA-861 Extension Block */
 225         if (!found && edid->extension_flag && buf_size >= EDID_EXT_SIZE) {
 226                 struct edid_cea861_info *info =
 227                         (struct edid_cea861_info *)(buf + sizeof(*edid));
 228
 229                 if (info->extension_tag == EDID_CEA861_EXTENSION_TAG) {
 230                         int count = EDID_CEA861_DTD_COUNT(*info);
 231                         int offset = info->dtd_offset;
 232                         int size = count * sizeof(struct edid_detailed_timing);
 233
 234                         if (offset >= 4 && offset + size < EDID_SIZE)
 235                                 found = edid_find_valid_timing(
 236                                         (u8 *)info + offset, count, timing,
 237                                         mode_valid, mode_valid_priv);
 238                 }
 239         }
 240
 241         if (!found)
 242                 return -EINVAL;
 243
 244         if (edid->version != 1 || edid->revision < 4) {
 245                 debug("%s: EDID version %d.%d does not have required info\n",
 246                       __func__, edid->version, edid->revision);
 247                 *panel_bits_per_colourp = -1;
 248         } else  {
 249                 *panel_bits_per_colourp =
 250                         ((edid->video_input_definition & 0x70) >> 3) + 4;
 251         }
 252
 253         timing->hdmi_monitor = false;
 254         if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) {
 255                 struct edid_cea861_info *info =
 256                         (struct edid_cea861_info *)(buf + sizeof(*edid));
 257
 258                 if (info->extension_tag == EDID_CEA861_EXTENSION_TAG)
 259                         timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info);
 260         }
 261
 262         return 0;
 263 }
 264
 265 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
 266                     int *panel_bits_per_colourp)
 267 {
 268         return edid_get_timing_validate(buf, buf_size, timing,
 269                                         panel_bits_per_colourp, NULL, NULL);
 270 }
 271
 272
 273 /**
 274  * Snip the tailing whitespace/return of a string.
 275  *
 276  * @param string        The string to be snipped
 277  * Return: the snipped string
 278  */
 279 static char *snip(char *string)
 280 {
 281         char *s;
 282
 283         /*
 284          * This is always a 13 character buffer
 285          * and it's not always terminated.
 286          */
 287         string[12] = '\0';
 288         s = &string[strlen(string) - 1];
 289
 290         while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
 291                         *s == '\0'))
 292                 *(s--) = '\0';
 293
 294         return string;
 295 }
 296
 297 /**
 298  * Print an EDID monitor descriptor block
 299  *
 300  * @param monitor       The EDID monitor descriptor block
 301  * @have_timing         Modifies to 1 if the desciptor contains timing info
 302  */
 303 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
 304                            unsigned int *have_timing)
 305 {
 306         unsigned char *bytes = (unsigned char *)monitor;
 307         struct edid_detailed_timing *timing =
 308                         (struct edid_detailed_timing *)monitor;
 309
 310         if (bytes[0] == 0 && bytes[1] == 0) {
 311                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
 312                         printf("Monitor serial number: %s\n",
 313                                snip(monitor->data.string));
 314                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
 315                         printf("Monitor ID: %s\n",
 316                                snip(monitor->data.string));
 317                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 318                         printf("Monitor name: %s\n",
 319                                snip(monitor->data.string));
 320                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 321                         printf("Monitor range limits, horizontal sync: "
 322                                "%d-%d kHz, vertical refresh: "
 323                                "%d-%d Hz, max pixel clock: "
 324                                "%d MHz\n",
 325                                monitor->data.range_data.horizontal_min,
 326                                monitor->data.range_data.horizontal_max,
 327                                monitor->data.range_data.vertical_min,
 328                                monitor->data.range_data.vertical_max,
 329                                monitor->data.range_data.pixel_clock_max * 10);
 330         } else {
 331                 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 332                 uint32_t h_total, v_total, vfreq;
 333
 334                 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 335                 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 336                 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 337                 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 338                 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 339
 340                 h_total = h_active + h_blanking;
 341                 v_total = v_active + v_blanking;
 342                 if (v_total > 0 && h_total > 0)
 343                         vfreq = pixclock / (v_total * h_total);
 344                 else
 345                         vfreq = 1; /* Error case */
 346                 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 347                        v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 348                 *have_timing = 1;
 349         }
 350 }
 351
 352 /**
 353  * Get the manufacturer name from an EDID info.
 354  *
 355  * @param edid_info     The EDID info to be printed
 356  * @param name          Returns the string of the manufacturer name
 357  */
 358 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 359 {
 360         name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 361         name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 362         name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 363         name[3] = '\0';
 364 }
 365
 366 void edid_print_info(struct edid1_info *edid_info)
 367 {
 368         int i;
 369         char manufacturer[4];
 370         unsigned int have_timing = 0;
 371         uint32_t serial_number;
 372
 373         if (edid_check_info(edid_info)) {
 374                 printf("Not a valid EDID\n");
 375                 return;
 376         }
 377
 378         printf("EDID version: %d.%d\n",
 379                edid_info->version, edid_info->revision);
 380
 381         printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 382
 383         edid_get_manufacturer_name(edid_info, manufacturer);
 384         printf("Manufacturer: %s\n", manufacturer);
 385
 386         serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 387         if (serial_number != 0xffffffff) {
 388                 if (strcmp(manufacturer, "MAG") == 0)
 389                         serial_number -= 0x7000000;
 390                 if (strcmp(manufacturer, "OQI") == 0)
 391                         serial_number -= 456150000;
 392                 if (strcmp(manufacturer, "VSC") == 0)
 393                         serial_number -= 640000000;
 394         }
 395         printf("Serial number: %08x\n", serial_number);
 396         printf("Manufactured in week: %d year: %d\n",
 397                edid_info->week, edid_info->year + 1990);
 398
 399         printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 400                EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 401                "digital signal, " : "analog signal, ",
 402                EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 403                EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 404                ", blank to black" : "",
 405                EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 406                ", separate sync" : "",
 407                EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 408                ", composite sync" : "",
 409                EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 410                ", sync on green" : "",
 411                EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 412                ", serration v" : "");
 413
 414         printf("Monitor is %s\n",
 415                EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 416
 417         printf("Maximum visible display size: %d cm x %d cm\n",
 418                edid_info->max_size_horizontal,
 419                edid_info->max_size_vertical);
 420
 421         printf("Power management features: %s%s, %s%s, %s%s\n",
 422                EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 423                "" : "no ", "active off",
 424                EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 425                EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 426
 427         printf("Estabilished timings:\n");
 428         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 429                 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 430         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 431                 printf("\t720x400\t\t88 Hz (XGA2)\n");
 432         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 433                 printf("\t640x480\t\t60 Hz (VGA)\n");
 434         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 435                 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 436         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 437                 printf("\t640x480\t\t72 Hz (VESA)\n");
 438         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 439                 printf("\t640x480\t\t75 Hz (VESA)\n");
 440         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 441                 printf("\t800x600\t\t56 Hz (VESA)\n");
 442         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 443                 printf("\t800x600\t\t60 Hz (VESA)\n");
 444         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 445                 printf("\t800x600\t\t72 Hz (VESA)\n");
 446         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 447                 printf("\t800x600\t\t75 Hz (VESA)\n");
 448         if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 449                 printf("\t832x624\t\t75 Hz (Mac II)\n");
 450         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 451                 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 452         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 453                 printf("\t1024x768\t60 Hz (VESA)\n");
 454         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 455                 printf("\t1024x768\t70 Hz (VESA)\n");
 456         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 457                 printf("\t1024x768\t75 Hz (VESA)\n");
 458         if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 459                 printf("\t1280x1024\t75 (VESA)\n");
 460         if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 461                 printf("\t1152x870\t75 (Mac II)\n");
 462
 463         /* Standard timings. */
 464         printf("Standard timings:\n");
 465         for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 466                 unsigned int aspect = 10000;
 467                 unsigned int x, y;
 468                 unsigned char xres, vfreq;
 469
 470                 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 471                 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 472                 if ((xres != vfreq) ||
 473                     ((xres != 0) && (xres != 1)) ||
 474                     ((vfreq != 0) && (vfreq != 1))) {
 475                         switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 476                                         i)) {
 477                         case ASPECT_625:
 478                                 aspect = 6250;
 479                                 break;
 480                         case ASPECT_75:
 481                                 aspect = 7500;
 482                                 break;
 483                         case ASPECT_8:
 484                                 aspect = 8000;
 485                                 break;
 486                         case ASPECT_5625:
 487                                 aspect = 5625;
 488                                 break;
 489                         }
 490                         x = (xres + 31) * 8;
 491                         y = x * aspect / 10000;
 492                         printf("\t%dx%d%c\t%d Hz\n", x, y,
 493                                x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 494                         have_timing = 1;
 495                 }
 496         }
 497
 498         /* Detailed timing information. */
 499         for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 500                         i++) {
 501                 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 502                                &have_timing);
 503         }
 504
 505         if (!have_timing)
 506                 printf("\tNone\n");
 507 }