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 int edid_get_timing_validate(u8 *buf, int buf_size,
 173                              struct display_timing *timing,
 174                              int *panel_bits_per_colourp,
 175                              bool (*mode_valid)(void *priv,
 176                                         const struct display_timing *timing),
 177                              void *mode_valid_priv)
 178 {
 179         struct edid1_info *edid = (struct edid1_info *)buf;
 180         bool timing_done;
 181         int i;
 182
 183         if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
 184                 debug("%s: Invalid buffer\n", __func__);
 185                 return -EINVAL;
 186         }
 187
 188         if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
 189                 debug("%s: Not a digital display\n", __func__);
 190                 return -ENOSYS;
 191         }
 192
 193         if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
 194                 debug("%s: No preferred timing\n", __func__);
 195                 return -ENOENT;
 196         }
 197
 198         /* Look for detailed timing */
 199         timing_done = false;
 200         for (i = 0; i < 4; i++) {
 201                 struct edid_monitor_descriptor *desc;
 202
 203                 desc = &edid->monitor_details.descriptor[i];
 204                 if (desc->zero_flag_1 != 0) {
 205                         decode_timing((u8 *)desc, timing);
 206                         if (mode_valid)
 207                                 timing_done = mode_valid(mode_valid_priv,
 208                                                          timing);
 209                         else
 210                                 timing_done = true;
 211
 212                         if (timing_done)
 213                                 break;
 214                 }
 215         }
 216         if (!timing_done)
 217                 return -EINVAL;
 218
 219         if (edid->version != 1 || edid->revision < 4) {
 220                 debug("%s: EDID version %d.%d does not have required info\n",
 221                       __func__, edid->version, edid->revision);
 222                 *panel_bits_per_colourp = -1;
 223         } else  {
 224                 *panel_bits_per_colourp =
 225                         ((edid->video_input_definition & 0x70) >> 3) + 4;
 226         }
 227
 228         timing->hdmi_monitor = false;
 229         if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) {
 230                 struct edid_cea861_info *info =
 231                         (struct edid_cea861_info *)(buf + sizeof(*edid));
 232
 233                 if (info->extension_tag == EDID_CEA861_EXTENSION_TAG)
 234                         timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info);
 235         }
 236
 237         return 0;
 238 }
 239
 240 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
 241                     int *panel_bits_per_colourp)
 242 {
 243         return edid_get_timing_validate(buf, buf_size, timing,
 244                                         panel_bits_per_colourp, NULL, NULL);
 245 }
 246
 247
 248 /**
 249  * Snip the tailing whitespace/return of a string.
 250  *
 251  * @param string        The string to be snipped
 252  * @return the snipped string
 253  */
 254 static char *snip(char *string)
 255 {
 256         char *s;
 257
 258         /*
 259          * This is always a 13 character buffer
 260          * and it's not always terminated.
 261          */
 262         string[12] = '\0';
 263         s = &string[strlen(string) - 1];
 264
 265         while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
 266                         *s == '\0'))
 267                 *(s--) = '\0';
 268
 269         return string;
 270 }
 271
 272 /**
 273  * Print an EDID monitor descriptor block
 274  *
 275  * @param monitor       The EDID monitor descriptor block
 276  * @have_timing         Modifies to 1 if the desciptor contains timing info
 277  */
 278 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
 279                            unsigned int *have_timing)
 280 {
 281         unsigned char *bytes = (unsigned char *)monitor;
 282         struct edid_detailed_timing *timing =
 283                         (struct edid_detailed_timing *)monitor;
 284
 285         if (bytes[0] == 0 && bytes[1] == 0) {
 286                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
 287                         printf("Monitor serial number: %s\n",
 288                                snip(monitor->data.string));
 289                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
 290                         printf("Monitor ID: %s\n",
 291                                snip(monitor->data.string));
 292                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 293                         printf("Monitor name: %s\n",
 294                                snip(monitor->data.string));
 295                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 296                         printf("Monitor range limits, horizontal sync: "
 297                                "%d-%d kHz, vertical refresh: "
 298                                "%d-%d Hz, max pixel clock: "
 299                                "%d MHz\n",
 300                                monitor->data.range_data.horizontal_min,
 301                                monitor->data.range_data.horizontal_max,
 302                                monitor->data.range_data.vertical_min,
 303                                monitor->data.range_data.vertical_max,
 304                                monitor->data.range_data.pixel_clock_max * 10);
 305         } else {
 306                 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 307                 uint32_t h_total, v_total, vfreq;
 308
 309                 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 310                 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 311                 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 312                 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 313                 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 314
 315                 h_total = h_active + h_blanking;
 316                 v_total = v_active + v_blanking;
 317                 if (v_total > 0 && h_total > 0)
 318                         vfreq = pixclock / (v_total * h_total);
 319                 else
 320                         vfreq = 1; /* Error case */
 321                 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 322                        v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 323                 *have_timing = 1;
 324         }
 325 }
 326
 327 /**
 328  * Get the manufacturer name from an EDID info.
 329  *
 330  * @param edid_info     The EDID info to be printed
 331  * @param name          Returns the string of the manufacturer name
 332  */
 333 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 334 {
 335         name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 336         name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 337         name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 338         name[3] = '\0';
 339 }
 340
 341 void edid_print_info(struct edid1_info *edid_info)
 342 {
 343         int i;
 344         char manufacturer[4];
 345         unsigned int have_timing = 0;
 346         uint32_t serial_number;
 347
 348         if (edid_check_info(edid_info)) {
 349                 printf("Not a valid EDID\n");
 350                 return;
 351         }
 352
 353         printf("EDID version: %d.%d\n",
 354                edid_info->version, edid_info->revision);
 355
 356         printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 357
 358         edid_get_manufacturer_name(edid_info, manufacturer);
 359         printf("Manufacturer: %s\n", manufacturer);
 360
 361         serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 362         if (serial_number != 0xffffffff) {
 363                 if (strcmp(manufacturer, "MAG") == 0)
 364                         serial_number -= 0x7000000;
 365                 if (strcmp(manufacturer, "OQI") == 0)
 366                         serial_number -= 456150000;
 367                 if (strcmp(manufacturer, "VSC") == 0)
 368                         serial_number -= 640000000;
 369         }
 370         printf("Serial number: %08x\n", serial_number);
 371         printf("Manufactured in week: %d year: %d\n",
 372                edid_info->week, edid_info->year + 1990);
 373
 374         printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 375                EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 376                "digital signal, " : "analog signal, ",
 377                EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 378                EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 379                ", blank to black" : "",
 380                EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 381                ", separate sync" : "",
 382                EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 383                ", composite sync" : "",
 384                EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 385                ", sync on green" : "",
 386                EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 387                ", serration v" : "");
 388
 389         printf("Monitor is %s\n",
 390                EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 391
 392         printf("Maximum visible display size: %d cm x %d cm\n",
 393                edid_info->max_size_horizontal,
 394                edid_info->max_size_vertical);
 395
 396         printf("Power management features: %s%s, %s%s, %s%s\n",
 397                EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 398                "" : "no ", "active off",
 399                EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 400                EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 401
 402         printf("Estabilished timings:\n");
 403         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 404                 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 405         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 406                 printf("\t720x400\t\t88 Hz (XGA2)\n");
 407         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 408                 printf("\t640x480\t\t60 Hz (VGA)\n");
 409         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 410                 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 411         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 412                 printf("\t640x480\t\t72 Hz (VESA)\n");
 413         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 414                 printf("\t640x480\t\t75 Hz (VESA)\n");
 415         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 416                 printf("\t800x600\t\t56 Hz (VESA)\n");
 417         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 418                 printf("\t800x600\t\t60 Hz (VESA)\n");
 419         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 420                 printf("\t800x600\t\t72 Hz (VESA)\n");
 421         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 422                 printf("\t800x600\t\t75 Hz (VESA)\n");
 423         if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 424                 printf("\t832x624\t\t75 Hz (Mac II)\n");
 425         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 426                 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 427         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 428                 printf("\t1024x768\t60 Hz (VESA)\n");
 429         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 430                 printf("\t1024x768\t70 Hz (VESA)\n");
 431         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 432                 printf("\t1024x768\t75 Hz (VESA)\n");
 433         if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 434                 printf("\t1280x1024\t75 (VESA)\n");
 435         if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 436                 printf("\t1152x870\t75 (Mac II)\n");
 437
 438         /* Standard timings. */
 439         printf("Standard timings:\n");
 440         for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 441                 unsigned int aspect = 10000;
 442                 unsigned int x, y;
 443                 unsigned char xres, vfreq;
 444
 445                 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 446                 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 447                 if ((xres != vfreq) ||
 448                     ((xres != 0) && (xres != 1)) ||
 449                     ((vfreq != 0) && (vfreq != 1))) {
 450                         switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 451                                         i)) {
 452                         case ASPECT_625:
 453                                 aspect = 6250;
 454                                 break;
 455                         case ASPECT_75:
 456                                 aspect = 7500;
 457                                 break;
 458                         case ASPECT_8:
 459                                 aspect = 8000;
 460                                 break;
 461                         case ASPECT_5625:
 462                                 aspect = 5625;
 463                                 break;
 464                         }
 465                         x = (xres + 31) * 8;
 466                         y = x * aspect / 10000;
 467                         printf("\t%dx%d%c\t%d Hz\n", x, y,
 468                                x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 469                         have_timing = 1;
 470                 }
 471         }
 472
 473         /* Detailed timing information. */
 474         for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 475                         i++) {
 476                 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 477                                &have_timing);
 478         }
 479
 480         if (!have_timing)
 481                 printf("\tNone\n");
 482 }