edid-generate.c (15161B)
1/* 2 * QEMU EDID generator. 3 * 4 * This work is licensed under the terms of the GNU GPL, version 2 or later. 5 * See the COPYING file in the top-level directory. 6 */ 7#include "qemu/osdep.h" 8#include "qemu/bswap.h" 9#include "hw/display/edid.h" 10 11static const struct edid_mode { 12 uint32_t xres; 13 uint32_t yres; 14 uint32_t byte; 15 uint32_t xtra3; 16 uint32_t bit; 17 uint32_t dta; 18} modes[] = { 19 /* dea/dta extension timings (all @ 50 Hz) */ 20 { .xres = 5120, .yres = 2160, .dta = 125 }, 21 { .xres = 4096, .yres = 2160, .dta = 101 }, 22 { .xres = 3840, .yres = 2160, .dta = 96 }, 23 { .xres = 2560, .yres = 1080, .dta = 89 }, 24 { .xres = 2048, .yres = 1152 }, 25 { .xres = 1920, .yres = 1080, .dta = 31 }, 26 27 /* additional standard timings 3 (all @ 60Hz) */ 28 { .xres = 1920, .yres = 1200, .xtra3 = 10, .bit = 0 }, 29 { .xres = 1600, .yres = 1200, .xtra3 = 9, .bit = 2 }, 30 { .xres = 1680, .yres = 1050, .xtra3 = 9, .bit = 5 }, 31 { .xres = 1440, .yres = 900, .xtra3 = 8, .bit = 5 }, 32 { .xres = 1280, .yres = 1024, .xtra3 = 7, .bit = 1 }, 33 { .xres = 1280, .yres = 960, .xtra3 = 7, .bit = 3 }, 34 { .xres = 1280, .yres = 768, .xtra3 = 7, .bit = 6 }, 35 36 { .xres = 1920, .yres = 1440, .xtra3 = 11, .bit = 5 }, 37 { .xres = 1856, .yres = 1392, .xtra3 = 10, .bit = 3 }, 38 { .xres = 1792, .yres = 1344, .xtra3 = 10, .bit = 5 }, 39 { .xres = 1440, .yres = 1050, .xtra3 = 8, .bit = 1 }, 40 { .xres = 1360, .yres = 768, .xtra3 = 8, .bit = 7 }, 41 42 /* established timings (all @ 60Hz) */ 43 { .xres = 1024, .yres = 768, .byte = 36, .bit = 3 }, 44 { .xres = 800, .yres = 600, .byte = 35, .bit = 0 }, 45 { .xres = 640, .yres = 480, .byte = 35, .bit = 5 }, 46}; 47 48typedef struct Timings { 49 uint32_t xfront; 50 uint32_t xsync; 51 uint32_t xblank; 52 53 uint32_t yfront; 54 uint32_t ysync; 55 uint32_t yblank; 56 57 uint64_t clock; 58} Timings; 59 60static void generate_timings(Timings *timings, uint32_t refresh_rate, 61 uint32_t xres, uint32_t yres) 62{ 63 /* pull some realistic looking timings out of thin air */ 64 timings->xfront = xres * 25 / 100; 65 timings->xsync = xres * 3 / 100; 66 timings->xblank = xres * 35 / 100; 67 68 timings->yfront = yres * 5 / 1000; 69 timings->ysync = yres * 5 / 1000; 70 timings->yblank = yres * 35 / 1000; 71 72 timings->clock = ((uint64_t)refresh_rate * 73 (xres + timings->xblank) * 74 (yres + timings->yblank)) / 10000000; 75} 76 77static void edid_ext_dta(uint8_t *dta) 78{ 79 dta[0] = 0x02; 80 dta[1] = 0x03; 81 dta[2] = 0x05; 82 dta[3] = 0x00; 83 84 /* video data block */ 85 dta[4] = 0x40; 86} 87 88static void edid_ext_dta_mode(uint8_t *dta, uint8_t nr) 89{ 90 dta[dta[2]] = nr; 91 dta[2]++; 92 dta[4]++; 93} 94 95static int edid_std_mode(uint8_t *mode, uint32_t xres, uint32_t yres) 96{ 97 uint32_t aspect; 98 99 if (xres == 0 || yres == 0) { 100 mode[0] = 0x01; 101 mode[1] = 0x01; 102 return 0; 103 104 } else if (xres * 10 == yres * 16) { 105 aspect = 0; 106 } else if (xres * 3 == yres * 4) { 107 aspect = 1; 108 } else if (xres * 4 == yres * 5) { 109 aspect = 2; 110 } else if (xres * 9 == yres * 16) { 111 aspect = 3; 112 } else { 113 return -1; 114 } 115 116 if ((xres / 8) - 31 > 255) { 117 return -1; 118 } 119 120 mode[0] = (xres / 8) - 31; 121 mode[1] = ((aspect << 6) | (60 - 60)); 122 return 0; 123} 124 125static void edid_fill_modes(uint8_t *edid, uint8_t *xtra3, uint8_t *dta, 126 uint32_t maxx, uint32_t maxy) 127{ 128 const struct edid_mode *mode; 129 int std = 38; 130 int rc, i; 131 132 for (i = 0; i < ARRAY_SIZE(modes); i++) { 133 mode = modes + i; 134 135 if ((maxx && mode->xres > maxx) || 136 (maxy && mode->yres > maxy)) { 137 continue; 138 } 139 140 if (mode->byte) { 141 edid[mode->byte] |= (1 << mode->bit); 142 } else if (std < 54) { 143 rc = edid_std_mode(edid + std, mode->xres, mode->yres); 144 if (rc == 0) { 145 std += 2; 146 } 147 } else if (mode->xtra3 && xtra3) { 148 xtra3[mode->xtra3] |= (1 << mode->bit); 149 } 150 151 if (dta && mode->dta) { 152 edid_ext_dta_mode(dta, mode->dta); 153 } 154 } 155 156 while (std < 54) { 157 edid_std_mode(edid + std, 0, 0); 158 std += 2; 159 } 160} 161 162static void edid_checksum(uint8_t *edid, size_t len) 163{ 164 uint32_t sum = 0; 165 int i; 166 167 for (i = 0; i < len; i++) { 168 sum += edid[i]; 169 } 170 sum &= 0xff; 171 if (sum) { 172 edid[len] = 0x100 - sum; 173 } 174} 175 176static uint8_t *edid_desc_next(uint8_t *edid, uint8_t *dta, uint8_t *desc) 177{ 178 if (desc == NULL) { 179 return NULL; 180 } 181 if (desc + 18 + 18 < edid + 127) { 182 return desc + 18; 183 } 184 if (dta) { 185 if (desc < edid + 127) { 186 return dta + dta[2]; 187 } 188 if (desc + 18 + 18 < dta + 127) { 189 return desc + 18; 190 } 191 } 192 return NULL; 193} 194 195static void edid_desc_type(uint8_t *desc, uint8_t type) 196{ 197 desc[0] = 0; 198 desc[1] = 0; 199 desc[2] = 0; 200 desc[3] = type; 201 desc[4] = 0; 202} 203 204static void edid_desc_text(uint8_t *desc, uint8_t type, 205 const char *text) 206{ 207 size_t len; 208 209 edid_desc_type(desc, type); 210 memset(desc + 5, ' ', 13); 211 212 len = strlen(text); 213 if (len > 12) { 214 len = 12; 215 } 216 memcpy(desc + 5, text, len); 217 desc[5 + len] = '\n'; 218} 219 220static void edid_desc_ranges(uint8_t *desc) 221{ 222 edid_desc_type(desc, 0xfd); 223 224 /* vertical (50 -> 125 Hz) */ 225 desc[5] = 50; 226 desc[6] = 125; 227 228 /* horizontal (30 -> 160 kHz) */ 229 desc[7] = 30; 230 desc[8] = 160; 231 232 /* max dot clock (2550 MHz) */ 233 desc[9] = 2550 / 10; 234 235 /* no extended timing information */ 236 desc[10] = 0x01; 237 238 /* padding */ 239 desc[11] = '\n'; 240 memset(desc + 12, ' ', 6); 241} 242 243/* additional standard timings 3 */ 244static void edid_desc_xtra3_std(uint8_t *desc) 245{ 246 edid_desc_type(desc, 0xf7); 247 desc[5] = 10; 248} 249 250static void edid_desc_dummy(uint8_t *desc) 251{ 252 edid_desc_type(desc, 0x10); 253} 254 255static void edid_desc_timing(uint8_t *desc, uint32_t refresh_rate, 256 uint32_t xres, uint32_t yres, 257 uint32_t xmm, uint32_t ymm) 258{ 259 Timings timings; 260 generate_timings(&timings, refresh_rate, xres, yres); 261 stl_le_p(desc, timings.clock); 262 263 desc[2] = xres & 0xff; 264 desc[3] = timings.xblank & 0xff; 265 desc[4] = (((xres & 0xf00) >> 4) | 266 ((timings.xblank & 0xf00) >> 8)); 267 268 desc[5] = yres & 0xff; 269 desc[6] = timings.yblank & 0xff; 270 desc[7] = (((yres & 0xf00) >> 4) | 271 ((timings.yblank & 0xf00) >> 8)); 272 273 desc[8] = timings.xfront & 0xff; 274 desc[9] = timings.xsync & 0xff; 275 276 desc[10] = (((timings.yfront & 0x00f) << 4) | 277 ((timings.ysync & 0x00f) << 0)); 278 desc[11] = (((timings.xfront & 0x300) >> 2) | 279 ((timings.xsync & 0x300) >> 4) | 280 ((timings.yfront & 0x030) >> 2) | 281 ((timings.ysync & 0x030) >> 4)); 282 283 desc[12] = xmm & 0xff; 284 desc[13] = ymm & 0xff; 285 desc[14] = (((xmm & 0xf00) >> 4) | 286 ((ymm & 0xf00) >> 8)); 287 288 desc[17] = 0x18; 289} 290 291static uint32_t edid_to_10bit(float value) 292{ 293 return (uint32_t)(value * 1024 + 0.5); 294} 295 296static void edid_colorspace(uint8_t *edid, 297 float rx, float ry, 298 float gx, float gy, 299 float bx, float by, 300 float wx, float wy) 301{ 302 uint32_t red_x = edid_to_10bit(rx); 303 uint32_t red_y = edid_to_10bit(ry); 304 uint32_t green_x = edid_to_10bit(gx); 305 uint32_t green_y = edid_to_10bit(gy); 306 uint32_t blue_x = edid_to_10bit(bx); 307 uint32_t blue_y = edid_to_10bit(by); 308 uint32_t white_x = edid_to_10bit(wx); 309 uint32_t white_y = edid_to_10bit(wy); 310 311 edid[25] = (((red_x & 0x03) << 6) | 312 ((red_y & 0x03) << 4) | 313 ((green_x & 0x03) << 2) | 314 ((green_y & 0x03) << 0)); 315 edid[26] = (((blue_x & 0x03) << 6) | 316 ((blue_y & 0x03) << 4) | 317 ((white_x & 0x03) << 2) | 318 ((white_y & 0x03) << 0)); 319 edid[27] = red_x >> 2; 320 edid[28] = red_y >> 2; 321 edid[29] = green_x >> 2; 322 edid[30] = green_y >> 2; 323 edid[31] = blue_x >> 2; 324 edid[32] = blue_y >> 2; 325 edid[33] = white_x >> 2; 326 edid[34] = white_y >> 2; 327} 328 329static uint32_t qemu_edid_dpi_from_mm(uint32_t mm, uint32_t res) 330{ 331 return res * 254 / 10 / mm; 332} 333 334uint32_t qemu_edid_dpi_to_mm(uint32_t dpi, uint32_t res) 335{ 336 return res * 254 / 10 / dpi; 337} 338 339static void init_displayid(uint8_t *did) 340{ 341 did[0] = 0x70; /* display id extension */ 342 did[1] = 0x13; /* version 1.3 */ 343 did[2] = 4; /* length */ 344 did[3] = 0x03; /* product type (0x03 == standalone display device) */ 345 edid_checksum(did + 1, did[2] + 4); 346} 347 348static void qemu_displayid_generate(uint8_t *did, uint32_t refresh_rate, 349 uint32_t xres, uint32_t yres, 350 uint32_t xmm, uint32_t ymm) 351{ 352 Timings timings; 353 generate_timings(&timings, refresh_rate, xres, yres); 354 355 did[0] = 0x70; /* display id extension */ 356 did[1] = 0x13; /* version 1.3 */ 357 did[2] = 23; /* length */ 358 did[3] = 0x03; /* product type (0x03 == standalone display device) */ 359 360 did[5] = 0x03; /* Detailed Timings Data Block */ 361 did[6] = 0x00; /* revision */ 362 did[7] = 0x14; /* block length */ 363 364 did[8] = timings.clock & 0xff; 365 did[9] = (timings.clock & 0xff00) >> 8; 366 did[10] = (timings.clock & 0xff0000) >> 16; 367 368 did[11] = 0x88; /* leave aspect ratio undefined */ 369 370 stw_le_p(did + 12, 0xffff & (xres - 1)); 371 stw_le_p(did + 14, 0xffff & (timings.xblank - 1)); 372 stw_le_p(did + 16, 0xffff & (timings.xfront - 1)); 373 stw_le_p(did + 18, 0xffff & (timings.xsync - 1)); 374 375 stw_le_p(did + 20, 0xffff & (yres - 1)); 376 stw_le_p(did + 22, 0xffff & (timings.yblank - 1)); 377 stw_le_p(did + 24, 0xffff & (timings.yfront - 1)); 378 stw_le_p(did + 26, 0xffff & (timings.ysync - 1)); 379 380 edid_checksum(did + 1, did[2] + 4); 381} 382 383void qemu_edid_generate(uint8_t *edid, size_t size, 384 qemu_edid_info *info) 385{ 386 uint8_t *desc = edid + 54; 387 uint8_t *xtra3 = NULL; 388 uint8_t *dta = NULL; 389 uint8_t *did = NULL; 390 uint32_t width_mm, height_mm; 391 uint32_t refresh_rate = info->refresh_rate ? info->refresh_rate : 75000; 392 uint32_t dpi = 100; /* if no width_mm/height_mm */ 393 uint32_t large_screen = 0; 394 395 /* =============== set defaults =============== */ 396 397 if (!info->vendor || strlen(info->vendor) != 3) { 398 info->vendor = "RHT"; 399 } 400 if (!info->name) { 401 info->name = "QEMU Monitor"; 402 } 403 if (!info->prefx) { 404 info->prefx = 1024; 405 } 406 if (!info->prefy) { 407 info->prefy = 768; 408 } 409 if (info->prefx >= 4096 || info->prefy >= 4096) { 410 large_screen = 1; 411 } 412 if (info->width_mm && info->height_mm) { 413 width_mm = info->width_mm; 414 height_mm = info->height_mm; 415 dpi = qemu_edid_dpi_from_mm(width_mm, info->prefx); 416 } else { 417 width_mm = qemu_edid_dpi_to_mm(dpi, info->prefx); 418 height_mm = qemu_edid_dpi_to_mm(dpi, info->prefy); 419 } 420 421 /* =============== extensions =============== */ 422 423 if (size >= 256) { 424 dta = edid + 128; 425 edid[126]++; 426 edid_ext_dta(dta); 427 } 428 429 if (size >= 384 && large_screen) { 430 did = edid + 256; 431 edid[126]++; 432 init_displayid(did); 433 } 434 435 /* =============== header information =============== */ 436 437 /* fixed */ 438 edid[0] = 0x00; 439 edid[1] = 0xff; 440 edid[2] = 0xff; 441 edid[3] = 0xff; 442 edid[4] = 0xff; 443 edid[5] = 0xff; 444 edid[6] = 0xff; 445 edid[7] = 0x00; 446 447 /* manufacturer id, product code, serial number */ 448 uint16_t vendor_id = ((((info->vendor[0] - '@') & 0x1f) << 10) | 449 (((info->vendor[1] - '@') & 0x1f) << 5) | 450 (((info->vendor[2] - '@') & 0x1f) << 0)); 451 uint16_t model_nr = 0x1234; 452 uint32_t serial_nr = info->serial ? atoi(info->serial) : 0; 453 stw_be_p(edid + 8, vendor_id); 454 stw_le_p(edid + 10, model_nr); 455 stl_le_p(edid + 12, serial_nr); 456 457 /* manufacture week and year */ 458 edid[16] = 42; 459 edid[17] = 2014 - 1990; 460 461 /* edid version */ 462 edid[18] = 1; 463 edid[19] = 4; 464 465 466 /* =============== basic display parameters =============== */ 467 468 /* video input: digital, 8bpc, displayport */ 469 edid[20] = 0xa5; 470 471 /* screen size: undefined */ 472 edid[21] = width_mm / 10; 473 edid[22] = height_mm / 10; 474 475 /* display gamma: 2.2 */ 476 edid[23] = 220 - 100; 477 478 /* supported features bitmap: std sRGB, preferred timing */ 479 edid[24] = 0x06; 480 481 482 /* =============== chromaticity coordinates =============== */ 483 484 /* standard sRGB colorspace */ 485 edid_colorspace(edid, 486 0.6400, 0.3300, /* red */ 487 0.3000, 0.6000, /* green */ 488 0.1500, 0.0600, /* blue */ 489 0.3127, 0.3290); /* white point */ 490 491 /* =============== established timing bitmap =============== */ 492 /* =============== standard timing information =============== */ 493 494 /* both filled by edid_fill_modes() */ 495 496 497 /* =============== descriptor blocks =============== */ 498 499 if (!large_screen) { 500 /* The DTD section has only 12 bits to store the resolution */ 501 edid_desc_timing(desc, refresh_rate, info->prefx, info->prefy, 502 width_mm, height_mm); 503 desc = edid_desc_next(edid, dta, desc); 504 } 505 506 xtra3 = desc; 507 edid_desc_xtra3_std(xtra3); 508 desc = edid_desc_next(edid, dta, desc); 509 edid_fill_modes(edid, xtra3, dta, info->maxx, info->maxy); 510 /* 511 * dta video data block is finished at thus point, 512 * so dta descriptor offsets don't move any more. 513 */ 514 515 edid_desc_ranges(desc); 516 desc = edid_desc_next(edid, dta, desc); 517 518 if (desc && info->name) { 519 edid_desc_text(desc, 0xfc, info->name); 520 desc = edid_desc_next(edid, dta, desc); 521 } 522 523 if (desc && info->serial) { 524 edid_desc_text(desc, 0xff, info->serial); 525 desc = edid_desc_next(edid, dta, desc); 526 } 527 528 while (desc) { 529 edid_desc_dummy(desc); 530 desc = edid_desc_next(edid, dta, desc); 531 } 532 533 /* =============== display id extensions =============== */ 534 535 if (did && large_screen) { 536 qemu_displayid_generate(did, refresh_rate, info->prefx, info->prefy, 537 width_mm, height_mm); 538 } 539 540 /* =============== finish up =============== */ 541 542 edid_checksum(edid, 127); 543 if (dta) { 544 edid_checksum(dta, 127); 545 } 546 if (did) { 547 edid_checksum(did, 127); 548 } 549} 550 551size_t qemu_edid_size(uint8_t *edid) 552{ 553 uint32_t exts; 554 555 if (edid[0] != 0x00 || 556 edid[1] != 0xff) { 557 /* doesn't look like a valid edid block */ 558 return 0; 559 } 560 561 exts = edid[126]; 562 return 128 * (exts + 1); 563}