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
  89         /* Edid contains pixel clock in terms of 10KHz */
  90         set_entry(&timing->pixelclock, (buf[0] + (buf[1] << 8)) * 10000);
  91         x_mm = (buf[12] + ((buf[14] & 0xf0) << 4));
  92         y_mm = (buf[13] + ((buf[14] & 0x0f) << 8));
  93         ha = (buf[2] + ((buf[4] & 0xf0) << 4));
  94         hbl = (buf[3] + ((buf[4] & 0x0f) << 8));
  95         hso = (buf[8] + ((buf[11] & 0xc0) << 2));
  96         hspw = (buf[9] + ((buf[11] & 0x30) << 4));
  97         hborder = buf[15];
  98         va = (buf[5] + ((buf[7] & 0xf0) << 4));
  99         vbl = (buf[6] + ((buf[7] & 0x0f) << 8));
 100         vso = ((buf[10] >> 4) + ((buf[11] & 0x0c) << 2));
 101         vspw = ((buf[10] & 0x0f) + ((buf[11] & 0x03) << 4));
 102         vborder = buf[16];
 103
 104         set_entry(&timing->hactive, ha);
 105         set_entry(&timing->hfront_porch, hso);
 106         set_entry(&timing->hback_porch, hbl - hso - hspw);
 107         set_entry(&timing->hsync_len, hspw);
 108
 109         set_entry(&timing->vactive, va);
 110         set_entry(&timing->vfront_porch, vso);
 111         set_entry(&timing->vback_porch, vbl - vso - vspw);
 112         set_entry(&timing->vsync_len, vspw);
 113
 114         debug("Detailed mode clock %u Hz, %d mm x %d mm\n"
 115               "               %04x %04x %04x %04x hborder %x\n"
 116               "               %04x %04x %04x %04x vborder %x\n",
 117               timing->pixelclock.typ,
 118               x_mm, y_mm,
 119               ha, ha + hso, ha + hso + hspw,
 120               ha + hbl, hborder,
 121               va, va + vso, va + vso + vspw,
 122               va + vbl, vborder);
 123 }
 124
 125 int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
 126                     int *panel_bits_per_colourp)
 127 {
 128         struct edid1_info *edid = (struct edid1_info *)buf;
 129         bool timing_done;
 130         int i;
 131
 132         if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
 133                 debug("%s: Invalid buffer\n", __func__);
 134                 return -EINVAL;
 135         }
 136
 137         if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
 138                 debug("%s: No preferred timing\n", __func__);
 139                 return -ENOENT;
 140         }
 141
 142         /* Look for detailed timing */
 143         timing_done = false;
 144         for (i = 0; i < 4; i++) {
 145                 struct edid_monitor_descriptor *desc;
 146
 147                 desc = &edid->monitor_details.descriptor[i];
 148                 if (desc->zero_flag_1 != 0) {
 149                         decode_timing((u8 *)desc, timing);
 150                         timing_done = true;
 151                         break;
 152                 }
 153         }
 154         if (!timing_done)
 155                 return -EINVAL;
 156
 157         if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
 158                 debug("%s: Not a digital display\n", __func__);
 159                 return -ENOSYS;
 160         }
 161         if (edid->version != 1 || edid->revision < 4) {
 162                 debug("%s: EDID version %d.%d does not have required info\n",
 163                       __func__, edid->version, edid->revision);
 164                 *panel_bits_per_colourp = -1;
 165         } else  {
 166                 *panel_bits_per_colourp =
 167                         ((edid->video_input_definition & 0x70) >> 3) + 4;
 168         }
 169
 170         return 0;
 171 }
 172
 173 /**
 174  * Snip the tailing whitespace/return of a string.
 175  *
 176  * @param string        The string to be snipped
 177  * @return the snipped string
 178  */
 179 static char *snip(char *string)
 180 {
 181         char *s;
 182
 183         /*
 184          * This is always a 13 character buffer
 185          * and it's not always terminated.
 186          */
 187         string[12] = '\0';
 188         s = &string[strlen(string) - 1];
 189
 190         while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
 191                         *s == '\0'))
 192                 *(s--) = '\0';
 193
 194         return string;
 195 }
 196
 197 /**
 198  * Print an EDID monitor descriptor block
 199  *
 200  * @param monitor       The EDID monitor descriptor block
 201  * @have_timing         Modifies to 1 if the desciptor contains timing info
 202  */
 203 static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
 204                            unsigned int *have_timing)
 205 {
 206         unsigned char *bytes = (unsigned char *)monitor;
 207         struct edid_detailed_timing *timing =
 208                         (struct edid_detailed_timing *)monitor;
 209
 210         if (bytes[0] == 0 && bytes[1] == 0) {
 211                 if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
 212                         printf("Monitor serial number: %s\n",
 213                                snip(monitor->data.string));
 214                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
 215                         printf("Monitor ID: %s\n",
 216                                snip(monitor->data.string));
 217                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
 218                         printf("Monitor name: %s\n",
 219                                snip(monitor->data.string));
 220                 else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
 221                         printf("Monitor range limits, horizontal sync: "
 222                                "%d-%d kHz, vertical refresh: "
 223                                "%d-%d Hz, max pixel clock: "
 224                                "%d MHz\n",
 225                                monitor->data.range_data.horizontal_min,
 226                                monitor->data.range_data.horizontal_max,
 227                                monitor->data.range_data.vertical_min,
 228                                monitor->data.range_data.vertical_max,
 229                                monitor->data.range_data.pixel_clock_max * 10);
 230         } else {
 231                 uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
 232                 uint32_t h_total, v_total, vfreq;
 233
 234                 pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
 235                 h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
 236                 h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
 237                 v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
 238                 v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
 239
 240                 h_total = h_active + h_blanking;
 241                 v_total = v_active + v_blanking;
 242                 if (v_total * h_total)
 243                         vfreq = pixclock / (v_total * h_total);
 244                 else
 245                         vfreq = 1; /* Error case */
 246                 printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
 247                        v_active, h_active > 1000 ? ' ' : '\t', vfreq);
 248                 *have_timing = 1;
 249         }
 250 }
 251
 252 /**
 253  * Get the manufacturer name from an EDID info.
 254  *
 255  * @param edid_info     The EDID info to be printed
 256  * @param name          Returns the string of the manufacturer name
 257  */
 258 static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
 259 {
 260         name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
 261         name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
 262         name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
 263         name[3] = '\0';
 264 }
 265
 266 void edid_print_info(struct edid1_info *edid_info)
 267 {
 268         int i;
 269         char manufacturer[4];
 270         unsigned int have_timing = 0;
 271         uint32_t serial_number;
 272
 273         if (edid_check_info(edid_info)) {
 274                 printf("Not a valid EDID\n");
 275                 return;
 276         }
 277
 278         printf("EDID version: %d.%d\n",
 279                edid_info->version, edid_info->revision);
 280
 281         printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
 282
 283         edid_get_manufacturer_name(edid_info, manufacturer);
 284         printf("Manufacturer: %s\n", manufacturer);
 285
 286         serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
 287         if (serial_number != 0xffffffff) {
 288                 if (strcmp(manufacturer, "MAG") == 0)
 289                         serial_number -= 0x7000000;
 290                 if (strcmp(manufacturer, "OQI") == 0)
 291                         serial_number -= 456150000;
 292                 if (strcmp(manufacturer, "VSC") == 0)
 293                         serial_number -= 640000000;
 294         }
 295         printf("Serial number: %08x\n", serial_number);
 296         printf("Manufactured in week: %d year: %d\n",
 297                edid_info->week, edid_info->year + 1990);
 298
 299         printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
 300                EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
 301                "digital signal, " : "analog signal, ",
 302                EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
 303                EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
 304                ", blank to black" : "",
 305                EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
 306                ", separate sync" : "",
 307                EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
 308                ", composite sync" : "",
 309                EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
 310                ", sync on green" : "",
 311                EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
 312                ", serration v" : "");
 313
 314         printf("Monitor is %s\n",
 315                EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
 316
 317         printf("Maximum visible display size: %d cm x %d cm\n",
 318                edid_info->max_size_horizontal,
 319                edid_info->max_size_vertical);
 320
 321         printf("Power management features: %s%s, %s%s, %s%s\n",
 322                EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
 323                "" : "no ", "active off",
 324                EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
 325                EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
 326
 327         printf("Estabilished timings:\n");
 328         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
 329                 printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
 330         if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
 331                 printf("\t720x400\t\t88 Hz (XGA2)\n");
 332         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
 333                 printf("\t640x480\t\t60 Hz (VGA)\n");
 334         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
 335                 printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
 336         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
 337                 printf("\t640x480\t\t72 Hz (VESA)\n");
 338         if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
 339                 printf("\t640x480\t\t75 Hz (VESA)\n");
 340         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
 341                 printf("\t800x600\t\t56 Hz (VESA)\n");
 342         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
 343                 printf("\t800x600\t\t60 Hz (VESA)\n");
 344         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
 345                 printf("\t800x600\t\t72 Hz (VESA)\n");
 346         if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
 347                 printf("\t800x600\t\t75 Hz (VESA)\n");
 348         if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
 349                 printf("\t832x624\t\t75 Hz (Mac II)\n");
 350         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
 351                 printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
 352         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
 353                 printf("\t1024x768\t60 Hz (VESA)\n");
 354         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
 355                 printf("\t1024x768\t70 Hz (VESA)\n");
 356         if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
 357                 printf("\t1024x768\t75 Hz (VESA)\n");
 358         if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
 359                 printf("\t1280x1024\t75 (VESA)\n");
 360         if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
 361                 printf("\t1152x870\t75 (Mac II)\n");
 362
 363         /* Standard timings. */
 364         printf("Standard timings:\n");
 365         for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
 366                 unsigned int aspect = 10000;
 367                 unsigned int x, y;
 368                 unsigned char xres, vfreq;
 369
 370                 xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
 371                 vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
 372                 if ((xres != vfreq) ||
 373                     ((xres != 0) && (xres != 1)) ||
 374                     ((vfreq != 0) && (vfreq != 1))) {
 375                         switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
 376                                         i)) {
 377                         case ASPECT_625:
 378                                 aspect = 6250;
 379                                 break;
 380                         case ASPECT_75:
 381                                 aspect = 7500;
 382                                 break;
 383                         case ASPECT_8:
 384                                 aspect = 8000;
 385                                 break;
 386                         case ASPECT_5625:
 387                                 aspect = 5625;
 388                                 break;
 389                         }
 390                         x = (xres + 31) * 8;
 391                         y = x * aspect / 10000;
 392                         printf("\t%dx%d%c\t%d Hz\n", x, y,
 393                                x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
 394                         have_timing = 1;
 395                 }
 396         }
 397
 398         /* Detailed timing information. */
 399         for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
 400                         i++) {
 401                 edid_print_dtd(&edid_info->monitor_details.descriptor[i],
 402                                &have_timing);
 403         }
 404
 405         if (!have_timing)
 406                 printf("\tNone\n");
 407 }