uboot/common/edid.c
<<
>>
Prefs
   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
  20int 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
  34int 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
  45int 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 */
  70static 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 */
  83static 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 */
 144static 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
 172static 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
 195int 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
 265int 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 */
 279static 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 */
 303static 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 */
 358static 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
 366void 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}
 508