common/edid.c

   1 /*
   2  * Copyright (c) 2012 The Chromium OS Authors.
   3  *
   4  * (C) Copyright 2010
   5  * Petr Stetiar <ynezz@true.cz>
   6  *
   7  * SPDX-License-Identifier:     GPL-2.0+
   8  *
   9  * Contains stolen code from ddcprobe project which is:
  10  * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
  11  */
  12
  13 #include <common.h>
  14 #include <edid.h>
  15 #include <errno.h>
  16 #include <fdtdec.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 = 127;
 152         if (end < 4 || end > 127)
 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 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
 173                     int *panel_bits_per_colourp)
 174 {
 175         struct edid1_info *edid = (struct edid1_info *)buf;
 176         bool timing_done;
 177         int i;
 178
 179         if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
 180                 debug("%s: Invalid buffer\n", __func__);
 181                 return -EINVAL;
 182         }
 183
 184         if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
 185                 debug("%s: No preferred timing\n", __func__);
 186                 return -ENOENT;
 187         }
 188
 189         /* Look for detailed timing */
 190         timing_done = false;
 191         for (i = 0; i < 4; i++) {
 192                 struct edid_monitor_descriptor *desc;
 193
 194                 desc = &edid->monitor_details.descriptor[i];
 195                 if (desc->zero_flag_1 != 0) {
 196                         decode_timing((u8 *)desc, timing);
 197                         timing_done = true;
 198                         break;
 199                 }
 200         }
 201         if (!timing_done)
 202                 return -EINVAL;
 203
 204         if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
 205                 debug("%s: Not a digital display\n", __func__);
 206                 return -ENOSYS;
 207         }
 208         if (edid->version != 1 || edid->revision < 4) {
 209                 debug("%s: EDID version %d.%d does not have required info\n",
 210                       __func__, edid->version, edid->revision);
 211                 *panel_bits_per_colourp = -1;
 212         } else  {
 213                 *panel_bits_per_colourp =
 214                         ((edid->video_input_definition & 0x70) >> 3) + 4;
 215         }
 216
 217         timing->hdmi_monitor = false;
 218         if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) {
 219                 struct edid_cea861_info *info =
 220                         (struct edid_cea861_info *)(buf + sizeof(*edid));
 221
 222                 if (info->extension_tag == EDID_CEA861_EXTENSION_TAG)
 223                         timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info);
 224         }
 225
 226         return 0;
 227 }
 228
 229 /**
 230  * Snip the tailing whitespace/return of a string.
 231  *
 232  * @param string        The string to be snipped
 233  * @return the snipped string
 234  */
 235 static char *snip(char *string)
 236 {
 237         char *s;
 238
 239         /*
 240          * This is always a 13 character buffer
 241          * and it's not always terminated.
 242          */
 243         string[12] = '\0';
 244         s = &string[strlen(string) - 1];
 245
 246         while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
 247                         *s == '\0'))
 248                 *(s--) = '\0';
 249
 250         return string;
 251 }
 252
 253 /**
 254  * Print an EDID monitor descriptor block
 255  *
 256  * @param monitor       The EDID monitor descriptor block
 257  * @have_timing         Modifies to 1 if the desciptor contains timing info
 258  */
 259 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
 260                            unsigned int *have_timing)
 261 {
 262         unsigned char *bytes = (unsigned char *)monitor;
 263         struct edid_detailed_timing *timing =
 264                         (struct edid_detailed_timing *)monitor;
 265
 266         if (bytes[0] == 0 && bytes[1] == 0) {
 267                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
 268                         printf("Monitor serial number: %s\n",
 269                                snip(monitor->data.string));
 270                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
 271                         printf("Monitor ID: %s\n",
 272                                snip(monitor->data.string));
 273                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 274                         printf("Monitor name: %s\n",
 275                                snip(monitor->data.string));
 276                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 277                         printf("Monitor range limits, horizontal sync: "
 278                                "%d-%d kHz, vertical refresh: "
 279                                "%d-%d Hz, max pixel clock: "
 280                                "%d MHz\n",
 281                                monitor->data.range_data.horizontal_min,
 282                                monitor->data.range_data.horizontal_max,
 283                                monitor->data.range_data.vertical_min,
 284                                monitor->data.range_data.vertical_max,
 285                                monitor->data.range_data.pixel_clock_max * 10);
 286         } else {
 287                 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 288                 uint32_t h_total, v_total, vfreq;
 289
 290                 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 291                 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 292                 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 293                 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 294                 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 295
 296                 h_total = h_active + h_blanking;
 297                 v_total = v_active + v_blanking;
 298                 if (v_total * h_total)
 299                         vfreq = pixclock / (v_total * h_total);
 300                 else
 301                         vfreq = 1; /* Error case */
 302                 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 303                        v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 304                 *have_timing = 1;
 305         }
 306 }
 307
 308 /**
 309  * Get the manufacturer name from an EDID info.
 310  *
 311  * @param edid_info     The EDID info to be printed
 312  * @param name          Returns the string of the manufacturer name
 313  */
 314 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 315 {
 316         name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 317         name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 318         name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 319         name[3] = '\0';
 320 }
 321
 322 void edid_print_info(struct edid1_info *edid_info)
 323 {
 324         int i;
 325         char manufacturer[4];
 326         unsigned int have_timing = 0;
 327         uint32_t serial_number;
 328
 329         if (edid_check_info(edid_info)) {
 330                 printf("Not a valid EDID\n");
 331                 return;
 332         }
 333
 334         printf("EDID version: %d.%d\n",
 335                edid_info->version, edid_info->revision);
 336
 337         printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 338
 339         edid_get_manufacturer_name(edid_info, manufacturer);
 340         printf("Manufacturer: %s\n", manufacturer);
 341
 342         serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 343         if (serial_number != 0xffffffff) {
 344                 if (strcmp(manufacturer, "MAG") == 0)
 345                         serial_number -= 0x7000000;
 346                 if (strcmp(manufacturer, "OQI") == 0)
 347                         serial_number -= 456150000;
 348                 if (strcmp(manufacturer, "VSC") == 0)
 349                         serial_number -= 640000000;
 350         }
 351         printf("Serial number: %08x\n", serial_number);
 352         printf("Manufactured in week: %d year: %d\n",
 353                edid_info->week, edid_info->year + 1990);
 354
 355         printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 356                EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 357                "digital signal, " : "analog signal, ",
 358                EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 359                EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 360                ", blank to black" : "",
 361                EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 362                ", separate sync" : "",
 363                EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 364                ", composite sync" : "",
 365                EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 366                ", sync on green" : "",
 367                EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 368                ", serration v" : "");
 369
 370         printf("Monitor is %s\n",
 371                EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 372
 373         printf("Maximum visible display size: %d cm x %d cm\n",
 374                edid_info->max_size_horizontal,
 375                edid_info->max_size_vertical);
 376
 377         printf("Power management features: %s%s, %s%s, %s%s\n",
 378                EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 379                "" : "no ", "active off",
 380                EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 381                EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 382
 383         printf("Estabilished timings:\n");
 384         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 385                 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 386         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 387                 printf("\t720x400\t\t88 Hz (XGA2)\n");
 388         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 389                 printf("\t640x480\t\t60 Hz (VGA)\n");
 390         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 391                 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 392         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 393                 printf("\t640x480\t\t72 Hz (VESA)\n");
 394         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 395                 printf("\t640x480\t\t75 Hz (VESA)\n");
 396         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 397                 printf("\t800x600\t\t56 Hz (VESA)\n");
 398         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 399                 printf("\t800x600\t\t60 Hz (VESA)\n");
 400         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 401                 printf("\t800x600\t\t72 Hz (VESA)\n");
 402         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 403                 printf("\t800x600\t\t75 Hz (VESA)\n");
 404         if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 405                 printf("\t832x624\t\t75 Hz (Mac II)\n");
 406         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 407                 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 408         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 409                 printf("\t1024x768\t60 Hz (VESA)\n");
 410         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 411                 printf("\t1024x768\t70 Hz (VESA)\n");
 412         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 413                 printf("\t1024x768\t75 Hz (VESA)\n");
 414         if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 415                 printf("\t1280x1024\t75 (VESA)\n");
 416         if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 417                 printf("\t1152x870\t75 (Mac II)\n");
 418
 419         /* Standard timings. */
 420         printf("Standard timings:\n");
 421         for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 422                 unsigned int aspect = 10000;
 423                 unsigned int x, y;
 424                 unsigned char xres, vfreq;
 425
 426                 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 427                 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 428                 if ((xres != vfreq) ||
 429                     ((xres != 0) && (xres != 1)) ||
 430                     ((vfreq != 0) && (vfreq != 1))) {
 431                         switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 432                                         i)) {
 433                         case ASPECT_625:
 434                                 aspect = 6250;
 435                                 break;
 436                         case ASPECT_75:
 437                                 aspect = 7500;
 438                                 break;
 439                         case ASPECT_8:
 440                                 aspect = 8000;
 441                                 break;
 442                         case ASPECT_5625:
 443                                 aspect = 5625;
 444                                 break;
 445                         }
 446                         x = (xres + 31) * 8;
 447                         y = x * aspect / 10000;
 448                         printf("\t%dx%d%c\t%d Hz\n", x, y,
 449                                x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 450                         have_timing = 1;
 451                 }
 452         }
 453
 454         /* Detailed timing information. */
 455         for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 456                         i++) {
 457                 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 458                                &have_timing);
 459         }
 460
 461         if (!have_timing)
 462                 printf("\tNone\n");
 463 }