uboot/common/edid.c
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   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
 172int 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_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
 189                debug("%s: No preferred timing\n", __func__);
 190                return -ENOENT;
 191        }
 192
 193        /* Look for detailed timing */
 194        timing_done = false;
 195        for (i = 0; i < 4; i++) {
 196                struct edid_monitor_descriptor *desc;
 197
 198                desc = &edid->monitor_details.descriptor[i];
 199                if (desc->zero_flag_1 != 0) {
 200                        decode_timing((u8 *)desc, timing);
 201                        if (mode_valid)
 202                                timing_done = mode_valid(mode_valid_priv,
 203                                                         timing);
 204                        else
 205                                timing_done = true;
 206
 207                        if (timing_done)
 208                                break;
 209                }
 210        }
 211        if (!timing_done)
 212                return -EINVAL;
 213
 214        if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
 215                debug("%s: Not a digital display\n", __func__);
 216                return -ENOSYS;
 217        }
 218        if (edid->version != 1 || edid->revision < 4) {
 219                debug("%s: EDID version %d.%d does not have required info\n",
 220                      __func__, edid->version, edid->revision);
 221                *panel_bits_per_colourp = -1;
 222        } else  {
 223                *panel_bits_per_colourp =
 224                        ((edid->video_input_definition & 0x70) >> 3) + 4;
 225        }
 226
 227        timing->hdmi_monitor = false;
 228        if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) {
 229                struct edid_cea861_info *info =
 230                        (struct edid_cea861_info *)(buf + sizeof(*edid));
 231
 232                if (info->extension_tag == EDID_CEA861_EXTENSION_TAG)
 233                        timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info);
 234        }
 235
 236        return 0;
 237}
 238
 239int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
 240                    int *panel_bits_per_colourp)
 241{
 242        return edid_get_timing_validate(buf, buf_size, timing,
 243                                        panel_bits_per_colourp, NULL, NULL);
 244}
 245
 246
 247/**
 248 * Snip the tailing whitespace/return of a string.
 249 *
 250 * @param string        The string to be snipped
 251 * @return the snipped string
 252 */
 253static char *snip(char *string)
 254{
 255        char *s;
 256
 257        /*
 258         * This is always a 13 character buffer
 259         * and it's not always terminated.
 260         */
 261        string[12] = '\0';
 262        s = &string[strlen(string) - 1];
 263
 264        while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
 265                        *s == '\0'))
 266                *(s--) = '\0';
 267
 268        return string;
 269}
 270
 271/**
 272 * Print an EDID monitor descriptor block
 273 *
 274 * @param monitor       The EDID monitor descriptor block
 275 * @have_timing         Modifies to 1 if the desciptor contains timing info
 276 */
 277static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
 278                           unsigned int *have_timing)
 279{
 280        unsigned char *bytes = (unsigned char *)monitor;
 281        struct edid_detailed_timing *timing =
 282                        (struct edid_detailed_timing *)monitor;
 283
 284        if (bytes[0] == 0 && bytes[1] == 0) {
 285                if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
 286                        printf("Monitor serial number: %s\n",
 287                               snip(monitor->data.string));
 288                else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
 289                        printf("Monitor ID: %s\n",
 290                               snip(monitor->data.string));
 291                else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 292                        printf("Monitor name: %s\n",
 293                               snip(monitor->data.string));
 294                else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 295                        printf("Monitor range limits, horizontal sync: "
 296                               "%d-%d kHz, vertical refresh: "
 297                               "%d-%d Hz, max pixel clock: "
 298                               "%d MHz\n",
 299                               monitor->data.range_data.horizontal_min,
 300                               monitor->data.range_data.horizontal_max,
 301                               monitor->data.range_data.vertical_min,
 302                               monitor->data.range_data.vertical_max,
 303                               monitor->data.range_data.pixel_clock_max * 10);
 304        } else {
 305                uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 306                uint32_t h_total, v_total, vfreq;
 307
 308                pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 309                h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 310                h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 311                v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 312                v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 313
 314                h_total = h_active + h_blanking;
 315                v_total = v_active + v_blanking;
 316                if (v_total > 0 && h_total > 0)
 317                        vfreq = pixclock / (v_total * h_total);
 318                else
 319                        vfreq = 1; /* Error case */
 320                printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 321                       v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 322                *have_timing = 1;
 323        }
 324}
 325
 326/**
 327 * Get the manufacturer name from an EDID info.
 328 *
 329 * @param edid_info     The EDID info to be printed
 330 * @param name          Returns the string of the manufacturer name
 331 */
 332static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 333{
 334        name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 335        name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 336        name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 337        name[3] = '\0';
 338}
 339
 340void edid_print_info(struct edid1_info *edid_info)
 341{
 342        int i;
 343        char manufacturer[4];
 344        unsigned int have_timing = 0;
 345        uint32_t serial_number;
 346
 347        if (edid_check_info(edid_info)) {
 348                printf("Not a valid EDID\n");
 349                return;
 350        }
 351
 352        printf("EDID version: %d.%d\n",
 353               edid_info->version, edid_info->revision);
 354
 355        printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 356
 357        edid_get_manufacturer_name(edid_info, manufacturer);
 358        printf("Manufacturer: %s\n", manufacturer);
 359
 360        serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 361        if (serial_number != 0xffffffff) {
 362                if (strcmp(manufacturer, "MAG") == 0)
 363                        serial_number -= 0x7000000;
 364                if (strcmp(manufacturer, "OQI") == 0)
 365                        serial_number -= 456150000;
 366                if (strcmp(manufacturer, "VSC") == 0)
 367                        serial_number -= 640000000;
 368        }
 369        printf("Serial number: %08x\n", serial_number);
 370        printf("Manufactured in week: %d year: %d\n",
 371               edid_info->week, edid_info->year + 1990);
 372
 373        printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 374               EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 375               "digital signal, " : "analog signal, ",
 376               EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 377               EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 378               ", blank to black" : "",
 379               EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 380               ", separate sync" : "",
 381               EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 382               ", composite sync" : "",
 383               EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 384               ", sync on green" : "",
 385               EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 386               ", serration v" : "");
 387
 388        printf("Monitor is %s\n",
 389               EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 390
 391        printf("Maximum visible display size: %d cm x %d cm\n",
 392               edid_info->max_size_horizontal,
 393               edid_info->max_size_vertical);
 394
 395        printf("Power management features: %s%s, %s%s, %s%s\n",
 396               EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 397               "" : "no ", "active off",
 398               EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 399               EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 400
 401        printf("Estabilished timings:\n");
 402        if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 403                printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 404        if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 405                printf("\t720x400\t\t88 Hz (XGA2)\n");
 406        if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 407                printf("\t640x480\t\t60 Hz (VGA)\n");
 408        if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 409                printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 410        if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 411                printf("\t640x480\t\t72 Hz (VESA)\n");
 412        if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 413                printf("\t640x480\t\t75 Hz (VESA)\n");
 414        if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 415                printf("\t800x600\t\t56 Hz (VESA)\n");
 416        if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 417                printf("\t800x600\t\t60 Hz (VESA)\n");
 418        if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 419                printf("\t800x600\t\t72 Hz (VESA)\n");
 420        if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 421                printf("\t800x600\t\t75 Hz (VESA)\n");
 422        if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 423                printf("\t832x624\t\t75 Hz (Mac II)\n");
 424        if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 425                printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 426        if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 427                printf("\t1024x768\t60 Hz (VESA)\n");
 428        if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 429                printf("\t1024x768\t70 Hz (VESA)\n");
 430        if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 431                printf("\t1024x768\t75 Hz (VESA)\n");
 432        if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 433                printf("\t1280x1024\t75 (VESA)\n");
 434        if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 435                printf("\t1152x870\t75 (Mac II)\n");
 436
 437        /* Standard timings. */
 438        printf("Standard timings:\n");
 439        for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 440                unsigned int aspect = 10000;
 441                unsigned int x, y;
 442                unsigned char xres, vfreq;
 443
 444                xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 445                vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 446                if ((xres != vfreq) ||
 447                    ((xres != 0) && (xres != 1)) ||
 448                    ((vfreq != 0) && (vfreq != 1))) {
 449                        switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 450                                        i)) {
 451                        case ASPECT_625:
 452                                aspect = 6250;
 453                                break;
 454                        case ASPECT_75:
 455                                aspect = 7500;
 456                                break;
 457                        case ASPECT_8:
 458                                aspect = 8000;
 459                                break;
 460                        case ASPECT_5625:
 461                                aspect = 5625;
 462                                break;
 463                        }
 464                        x = (xres + 31) * 8;
 465                        y = x * aspect / 10000;
 466                        printf("\t%dx%d%c\t%d Hz\n", x, y,
 467                               x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 468                        have_timing = 1;
 469                }
 470        }
 471
 472        /* Detailed timing information. */
 473        for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 474                        i++) {
 475                edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 476                               &have_timing);
 477        }
 478
 479        if (!have_timing)
 480                printf("\tNone\n");
 481}
 482