1 /* $NetBSD: vesagtf.c,v 1.4 2021/12/25 13:51:31 mlelstv Exp $ */ 2 3 /*- 4 * Copyright (c) 2006 Itronix Inc. 5 * All rights reserved. 6 * 7 * Written by Garrett D'Amore for Itronix Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. The name of Itronix Inc. may not be used to endorse 18 * or promote products derived from this software without specific 19 * prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND ANY EXPRESS 22 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY 25 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 31 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 /* 35 * This was derived from a userland GTF program supplied by NVIDIA. 36 * NVIDIA's original boilerplate follows. 37 * 38 * Note that I have heavily modified the program for use in the EDID 39 * kernel code for NetBSD, including removing the use of floating 40 * point operations and making significant adjustments to minimize 41 * error propagation while operating with integer only math. 42 * 43 * This has required the use of 64-bit integers in a few places, but 44 * the upshot is that for a calculation of 1920x1200x85 (as an 45 * example), the error deviates by only ~.004% relative to the 46 * floating point version. This error is *well* within VESA 47 * tolerances. 48 */ 49 50 /* 51 * Copyright (c) 2001, Andy Ritger aritger@nvidia.com 52 * All rights reserved. 53 * 54 * Redistribution and use in source and binary forms, with or without 55 * modification, are permitted provided that the following conditions 56 * are met: 57 * 58 * o Redistributions of source code must retain the above copyright 59 * notice, this list of conditions and the following disclaimer. 60 * o Redistributions in binary form must reproduce the above copyright 61 * notice, this list of conditions and the following disclaimer 62 * in the documentation and/or other materials provided with the 63 * distribution. 64 * o Neither the name of NVIDIA nor the names of its contributors 65 * may be used to endorse or promote products derived from this 66 * software without specific prior written permission. 67 * 68 * 69 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 70 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT 71 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 72 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 73 * THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 74 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 75 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 76 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 77 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 78 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 79 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 80 * POSSIBILITY OF SUCH DAMAGE. 81 * 82 * 83 * 84 * This program is based on the Generalized Timing Formula(GTF TM) 85 * Standard Version: 1.0, Revision: 1.0 86 * 87 * The GTF Document contains the following Copyright information: 88 * 89 * Copyright (c) 1994, 1995, 1996 - Video Electronics Standards 90 * Association. Duplication of this document within VESA member 91 * companies for review purposes is permitted. All other rights 92 * reserved. 93 * 94 * While every precaution has been taken in the preparation 95 * of this standard, the Video Electronics Standards Association and 96 * its contributors assume no responsibility for errors or omissions, 97 * and make no warranties, expressed or implied, of functionality 98 * of suitability for any purpose. The sample code contained within 99 * this standard may be used without restriction. 100 * 101 * 102 * 103 * The GTF EXCEL(TM) SPREADSHEET, a sample (and the definitive) 104 * implementation of the GTF Timing Standard, is available at: 105 * 106 * ftp://ftp.vesa.org/pub/GTF/GTF_V1R1.xls 107 * 108 * 109 * 110 * This program takes a desired resolution and vertical refresh rate, 111 * and computes mode timings according to the GTF Timing Standard. 112 * These mode timings can then be formatted as an XFree86 modeline 113 * or a mode description for use by fbset(8). 114 * 115 * 116 * 117 * NOTES: 118 * 119 * The GTF allows for computation of "margins" (the visible border 120 * surrounding the addressable video); on most non-overscan type 121 * systems, the margin period is zero. I've implemented the margin 122 * computations but not enabled it because 1) I don't really have 123 * any experience with this, and 2) neither XFree86 modelines nor 124 * fbset fb.modes provide an obvious way for margin timings to be 125 * included in their mode descriptions (needs more investigation). 126 * 127 * The GTF provides for computation of interlaced mode timings; 128 * I've implemented the computations but not enabled them, yet. 129 * I should probably enable and test this at some point. 130 * 131 * 132 * 133 * TODO: 134 * 135 * o Add support for interlaced modes. 136 * 137 * o Implement the other portions of the GTF: compute mode timings 138 * given either the desired pixel clock or the desired horizontal 139 * frequency. 140 * 141 * o It would be nice if this were more general purpose to do things 142 * outside the scope of the GTF: like generate double scan mode 143 * timings, for example. 144 * 145 * o Printing digits to the right of the decimal point when the 146 * digits are 0 annoys me. 147 * 148 * o Error checking. 149 * 150 */ 151 152 153 #ifdef _KERNEL 154 #include <sys/cdefs.h> 155 156 __KERNEL_RCSID(0, "$NetBSD: vesagtf.c,v 1.4 2021/12/25 13:51:31 mlelstv Exp $"); 157 #include <sys/types.h> 158 #include <sys/param.h> 159 #include <sys/systm.h> 160 #else 161 #include <stdio.h> 162 #include <stdlib.h> 163 #include <inttypes.h> 164 #endif 165 #include <dev/videomode/videomode.h> 166 #include <dev/videomode/vesagtf.h> 167 168 #define CELL_GRAN 8 /* assumed character cell granularity */ 169 170 /* C' and M' are part of the Blanking Duty Cycle computation */ 171 /* 172 * #define C_PRIME (((C - J) * K/256.0) + J) 173 * #define M_PRIME (K/256.0 * M) 174 */ 175 176 /* 177 * C' and M' multiplied by 256 to give integer math. Make sure to 178 * scale results using these back down, appropriately. 179 */ 180 #define C_PRIME256(p) (((p->C - p->J) * p->K) + (p->J * 256)) 181 #define M_PRIME256(p) (p->K * p->M) 182 183 #define DIVIDE(x,y) (((x) + ((y) / 2)) / (y)) 184 185 /* 186 * print_value() - print the result of the named computation; this is 187 * useful when comparing against the GTF EXCEL spreadsheet. 188 */ 189 190 #ifdef GTFDEBUG 191 192 static void 193 print_value(int n, const char *name, unsigned val) 194 { 195 printf("%2d: %-27s: %u\n", n, name, val); 196 } 197 #else 198 #define print_value(n, name, val) 199 #endif 200 201 202 /* 203 * vert_refresh() - as defined by the GTF Timing Standard, compute the 204 * Stage 1 Parameters using the vertical refresh frequency. In other 205 * words: input a desired resolution and desired refresh rate, and 206 * output the GTF mode timings. 207 * 208 * XXX All the code is in place to compute interlaced modes, but I don't 209 * feel like testing it right now. 210 * 211 * XXX margin computations are implemented but not tested (nor used by 212 * XFree86 of fbset mode descriptions, from what I can tell). 213 */ 214 215 void 216 vesagtf_mode_params(unsigned h_pixels, unsigned v_lines, unsigned freq, 217 struct vesagtf_params *params, int flags, struct videomode *vmp) 218 { 219 unsigned v_field_rqd; 220 unsigned top_margin; 221 unsigned bottom_margin; 222 unsigned interlace; 223 uint64_t h_period_est; 224 unsigned vsync_plus_bp; 225 unsigned v_back_porch __unused; 226 unsigned total_v_lines; 227 uint64_t v_field_est; 228 uint64_t h_period; 229 unsigned v_field_rate; 230 unsigned v_frame_rate __unused; 231 unsigned left_margin; 232 unsigned right_margin; 233 unsigned total_active_pixels; 234 uint64_t ideal_duty_cycle; 235 unsigned h_blank; 236 unsigned total_pixels; 237 unsigned pixel_freq; 238 239 unsigned h_sync; 240 unsigned h_front_porch; 241 unsigned v_odd_front_porch_lines; 242 243 #ifdef GTFDEBUG 244 unsigned h_freq; 245 #endif 246 247 /* 1. In order to give correct results, the number of horizontal 248 * pixels requested is first processed to ensure that it is divisible 249 * by the character size, by rounding it to the nearest character 250 * cell boundary: 251 * 252 * [H PIXELS RND] = ((ROUND([H PIXELS]/[CELL GRAN RND],0))*[CELLGRAN RND]) 253 */ 254 255 h_pixels = DIVIDE(h_pixels, CELL_GRAN) * CELL_GRAN; 256 257 print_value(1, "[H PIXELS RND]", h_pixels); 258 259 260 /* 2. If interlace is requested, the number of vertical lines assumed 261 * by the calculation must be halved, as the computation calculates 262 * the number of vertical lines per field. In either case, the 263 * number of lines is rounded to the nearest integer. 264 * 265 * [V LINES RND] = IF([INT RQD?]="y", ROUND([V LINES]/2,0), 266 * ROUND([V LINES],0)) 267 */ 268 269 v_lines = (flags & VESAGTF_FLAG_ILACE) ? DIVIDE(v_lines, 2) : v_lines; 270 271 print_value(2, "[V LINES RND]", v_lines); 272 273 274 /* 3. Find the frame rate required: 275 * 276 * [V FIELD RATE RQD] = IF([INT RQD?]="y", [I/P FREQ RQD]*2, 277 * [I/P FREQ RQD]) 278 */ 279 280 v_field_rqd = (flags & VESAGTF_FLAG_ILACE) ? (freq * 2) : (freq); 281 282 print_value(3, "[V FIELD RATE RQD]", v_field_rqd); 283 284 285 /* 4. Find number of lines in Top margin: 286 * 5. Find number of lines in Bottom margin: 287 * 288 * [TOP MARGIN (LINES)] = IF([MARGINS RQD?]="Y", 289 * ROUND(([MARGIN%]/100*[V LINES RND]),0), 290 * 0) 291 * 292 * Ditto for bottom margin. Note that instead of %, we use PPT, which 293 * is parts per thousand. This helps us with integer math. 294 */ 295 296 top_margin = bottom_margin = (flags & VESAGTF_FLAG_MARGINS) ? 297 DIVIDE(v_lines * params->margin_ppt, 1000) : 0; 298 299 print_value(4, "[TOP MARGIN (LINES)]", top_margin); 300 print_value(5, "[BOT MARGIN (LINES)]", bottom_margin); 301 302 303 /* 6. If interlace is required, then set variable [INTERLACE]=0.5: 304 * 305 * [INTERLACE]=(IF([INT RQD?]="y",0.5,0)) 306 * 307 * To make this integer friendly, we use some special hacks in step 308 * 7 below. Please read those comments to understand why I am using 309 * a whole number of 1.0 instead of 0.5 here. 310 */ 311 interlace = (flags & VESAGTF_FLAG_ILACE) ? 1 : 0; 312 313 print_value(6, "[2*INTERLACE]", interlace); 314 315 316 /* 7. Estimate the Horizontal period 317 * 318 * [H PERIOD EST] = ((1/[V FIELD RATE RQD]) - [MIN VSYNC+BP]/1000000) / 319 * ([V LINES RND] + (2*[TOP MARGIN (LINES)]) + 320 * [MIN PORCH RND]+[INTERLACE]) * 1000000 321 * 322 * To make it integer friendly, we pre-multiply the 1000000 to get to 323 * usec. This gives us: 324 * 325 * [H PERIOD EST] = ((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP]) / 326 * ([V LINES RND] + (2 * [TOP MARGIN (LINES)]) + 327 * [MIN PORCH RND]+[INTERLACE]) 328 * 329 * The other problem is that the interlace value is wrong. To get 330 * the interlace to a whole number, we multiply both the numerator and 331 * divisor by 2, so we can use a value of either 1 or 0 for the interlace 332 * factor. 333 * 334 * This gives us: 335 * 336 * [H PERIOD EST] = ((2*((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP])) / 337 * (2*([V LINES RND] + (2*[TOP MARGIN (LINES)]) + 338 * [MIN PORCH RND]) + [2*INTERLACE])) 339 * 340 * Finally we multiply by another 1000, to get value in picosec. 341 * Why picosec? To minimize rounding errors. Gotta love integer 342 * math and error propagation. 343 */ 344 345 h_period_est = DIVIDE(((DIVIDE(2000000000000ULL, v_field_rqd)) - 346 (2000000 * params->min_vsbp)), 347 ((2 * (v_lines + (2 * top_margin) + params->min_porch)) + interlace)); 348 349 print_value(7, "[H PERIOD EST (ps)]", h_period_est); 350 351 352 /* 8. Find the number of lines in V sync + back porch: 353 * 354 * [V SYNC+BP] = ROUND(([MIN VSYNC+BP]/[H PERIOD EST]),0) 355 * 356 * But recall that h_period_est is in psec. So multiply by 1000000. 357 */ 358 359 vsync_plus_bp = DIVIDE(params->min_vsbp * 1000000, h_period_est); 360 361 print_value(8, "[V SYNC+BP]", vsync_plus_bp); 362 363 364 /* 9. Find the number of lines in V back porch alone: 365 * 366 * [V BACK PORCH] = [V SYNC+BP] - [V SYNC RND] 367 * 368 * XXX is "[V SYNC RND]" a typo? should be [V SYNC RQD]? 369 */ 370 371 v_back_porch = vsync_plus_bp - params->vsync_rqd; 372 373 print_value(9, "[V BACK PORCH]", v_back_porch); 374 375 376 /* 10. Find the total number of lines in Vertical field period: 377 * 378 * [TOTAL V LINES] = [V LINES RND] + [TOP MARGIN (LINES)] + 379 * [BOT MARGIN (LINES)] + [V SYNC+BP] + [INTERLACE] + 380 * [MIN PORCH RND] 381 */ 382 383 total_v_lines = v_lines + top_margin + bottom_margin + vsync_plus_bp + 384 interlace + params->min_porch; 385 386 print_value(10, "[TOTAL V LINES]", total_v_lines); 387 388 389 /* 11. Estimate the Vertical field frequency: 390 * 391 * [V FIELD RATE EST] = 1 / [H PERIOD EST] / [TOTAL V LINES] * 1000000 392 * 393 * Again, we want to pre multiply by 10^9 to convert for nsec, thereby 394 * making it usable in integer math. 395 * 396 * So we get: 397 * 398 * [V FIELD RATE EST] = 1000000000 / [H PERIOD EST] / [TOTAL V LINES] 399 * 400 * This is all scaled to get the result in uHz. Again, we're trying to 401 * minimize error propagation. 402 */ 403 v_field_est = DIVIDE(DIVIDE(1000000000000000ULL, h_period_est), 404 total_v_lines); 405 406 print_value(11, "[V FIELD RATE EST(uHz)]", v_field_est); 407 408 409 /* 12. Find the actual horizontal period: 410 * 411 * [H PERIOD] = [H PERIOD EST] / ([V FIELD RATE RQD] / [V FIELD RATE EST]) 412 */ 413 414 h_period = DIVIDE(h_period_est * v_field_est, v_field_rqd * 1000); 415 416 print_value(12, "[H PERIOD(ps)]", h_period); 417 418 419 /* 13. Find the actual Vertical field frequency: 420 * 421 * [V FIELD RATE] = 1 / [H PERIOD] / [TOTAL V LINES] * 1000000 422 * 423 * And again, we convert to nsec ahead of time, giving us: 424 * 425 * [V FIELD RATE] = 1000000 / [H PERIOD] / [TOTAL V LINES] 426 * 427 * And another rescaling back to mHz. Gotta love it. 428 */ 429 430 v_field_rate = DIVIDE(1000000000000ULL, h_period * total_v_lines); 431 432 print_value(13, "[V FIELD RATE]", v_field_rate); 433 434 435 /* 14. Find the Vertical frame frequency: 436 * 437 * [V FRAME RATE] = (IF([INT RQD?]="y", [V FIELD RATE]/2, [V FIELD RATE])) 438 * 439 * N.B. that the result here is in mHz. 440 */ 441 442 v_frame_rate = (flags & VESAGTF_FLAG_ILACE) ? 443 v_field_rate / 2 : v_field_rate; 444 445 print_value(14, "[V FRAME RATE]", v_frame_rate); 446 447 448 /* 15. Find number of pixels in left margin: 449 * 16. Find number of pixels in right margin: 450 * 451 * [LEFT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y", 452 * (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 / 453 * [CELL GRAN RND]),0)) * [CELL GRAN RND], 454 * 0)) 455 * 456 * Again, we deal with margin percentages as PPT (parts per thousand). 457 * And the calculations for left and right are the same. 458 */ 459 460 left_margin = right_margin = (flags & VESAGTF_FLAG_MARGINS) ? 461 DIVIDE(DIVIDE(h_pixels * params->margin_ppt, 1000), 462 CELL_GRAN) * CELL_GRAN : 0; 463 464 print_value(15, "[LEFT MARGIN (PIXELS)]", left_margin); 465 print_value(16, "[RIGHT MARGIN (PIXELS)]", right_margin); 466 467 468 /* 17. Find total number of active pixels in image and left and right 469 * margins: 470 * 471 * [TOTAL ACTIVE PIXELS] = [H PIXELS RND] + [LEFT MARGIN (PIXELS)] + 472 * [RIGHT MARGIN (PIXELS)] 473 */ 474 475 total_active_pixels = h_pixels + left_margin + right_margin; 476 477 print_value(17, "[TOTAL ACTIVE PIXELS]", total_active_pixels); 478 479 480 /* 18. Find the ideal blanking duty cycle from the blanking duty cycle 481 * equation: 482 * 483 * [IDEAL DUTY CYCLE] = [C'] - ([M']*[H PERIOD]/1000) 484 * 485 * However, we have modified values for [C'] as [256*C'] and 486 * [M'] as [256*M']. Again the idea here is to get good scaling. 487 * We use 256 as the factor to make the math fast. 488 * 489 * Note that this means that we have to scale it appropriately in 490 * later calculations. 491 * 492 * The ending result is that our ideal_duty_cycle is 256000x larger 493 * than the duty cycle used by VESA. But again, this reduces error 494 * propagation. 495 */ 496 497 ideal_duty_cycle = 498 ((C_PRIME256(params) * 1000) - 499 (M_PRIME256(params) * h_period / 1000000)); 500 501 print_value(18, "[IDEAL DUTY CYCLE]", ideal_duty_cycle); 502 503 504 /* 19. Find the number of pixels in the blanking time to the nearest 505 * double character cell: 506 * 507 * [H BLANK (PIXELS)] = (ROUND(([TOTAL ACTIVE PIXELS] * 508 * [IDEAL DUTY CYCLE] / 509 * (100-[IDEAL DUTY CYCLE]) / 510 * (2*[CELL GRAN RND])), 0)) 511 * * (2*[CELL GRAN RND]) 512 * 513 * Of course, we adjust to make this rounding work in integer math. 514 */ 515 516 h_blank = DIVIDE(DIVIDE(total_active_pixels * ideal_duty_cycle, 517 (256000 * 100ULL) - ideal_duty_cycle), 518 2 * CELL_GRAN) * (2 * CELL_GRAN); 519 520 print_value(19, "[H BLANK (PIXELS)]", h_blank); 521 522 523 /* 20. Find total number of pixels: 524 * 525 * [TOTAL PIXELS] = [TOTAL ACTIVE PIXELS] + [H BLANK (PIXELS)] 526 */ 527 528 total_pixels = total_active_pixels + h_blank; 529 530 print_value(20, "[TOTAL PIXELS]", total_pixels); 531 532 533 /* 21. Find pixel clock frequency: 534 * 535 * [PIXEL FREQ] = [TOTAL PIXELS] / [H PERIOD] 536 * 537 * We calculate this in Hz rather than MHz, to get a value that 538 * is usable with integer math. Recall that the [H PERIOD] is in 539 * nsec. 540 */ 541 542 pixel_freq = DIVIDE(total_pixels * 1000000, DIVIDE(h_period, 1000)); 543 544 print_value(21, "[PIXEL FREQ]", pixel_freq); 545 546 547 /* 22. Find horizontal frequency: 548 * 549 * [H FREQ] = 1000 / [H PERIOD] 550 * 551 * I've ifdef'd this out, because we don't need it for any of 552 * our calculations. 553 * We calculate this in Hz rather than kHz, to avoid rounding 554 * errors. Recall that the [H PERIOD] is in usec. 555 */ 556 557 #ifdef GTFDEBUG 558 h_freq = 1000000000 / h_period; 559 560 print_value(22, "[H FREQ]", h_freq); 561 #endif 562 563 564 565 /* Stage 1 computations are now complete; I should really pass 566 the results to another function and do the Stage 2 567 computations, but I only need a few more values so I'll just 568 append the computations here for now */ 569 570 571 572 /* 17. Find the number of pixels in the horizontal sync period: 573 * 574 * [H SYNC (PIXELS)] =(ROUND(([H SYNC%] / 100 * [TOTAL PIXELS] / 575 * [CELL GRAN RND]),0))*[CELL GRAN RND] 576 * 577 * Rewriting for integer math: 578 * 579 * [H SYNC (PIXELS)]=(ROUND((H SYNC%] * [TOTAL PIXELS] / 100 / 580 * [CELL GRAN RND),0))*[CELL GRAN RND] 581 */ 582 583 h_sync = DIVIDE(((params->hsync_pct * total_pixels) / 100), CELL_GRAN) * 584 CELL_GRAN; 585 586 print_value(17, "[H SYNC (PIXELS)]", h_sync); 587 588 589 /* 18. Find the number of pixels in the horizontal front porch period: 590 * 591 * [H FRONT PORCH (PIXELS)] = ([H BLANK (PIXELS)]/2)-[H SYNC (PIXELS)] 592 * 593 * Note that h_blank is always an even number of characters (i.e. 594 * h_blank % (CELL_GRAN * 2) == 0) 595 */ 596 597 h_front_porch = (h_blank / 2) - h_sync; 598 599 print_value(18, "[H FRONT PORCH (PIXELS)]", h_front_porch); 600 601 602 /* 36. Find the number of lines in the odd front porch period: 603 * 604 * [V ODD FRONT PORCH(LINES)]=([MIN PORCH RND]+[INTERLACE]) 605 * 606 * Adjusting for the fact that the interlace is scaled: 607 * 608 * [V ODD FRONT PORCH(LINES)]=(([MIN PORCH RND] * 2) + [2*INTERLACE]) / 2 609 */ 610 611 v_odd_front_porch_lines = ((2 * params->min_porch) + interlace) / 2; 612 613 print_value(36, "[V ODD FRONT PORCH(LINES)]", v_odd_front_porch_lines); 614 615 616 /* finally, pack the results in the mode struct */ 617 618 vmp->hsync_start = h_pixels + h_front_porch; 619 vmp->hsync_end = vmp->hsync_start + h_sync; 620 vmp->htotal = total_pixels; 621 vmp->hdisplay = h_pixels; 622 623 vmp->vsync_start = v_lines + v_odd_front_porch_lines; 624 vmp->vsync_end = vmp->vsync_start + params->vsync_rqd; 625 vmp->vtotal = total_v_lines; 626 vmp->vdisplay = v_lines; 627 628 vmp->dot_clock = pixel_freq; 629 630 } 631 632 void 633 vesagtf_mode(unsigned x, unsigned y, unsigned refresh, struct videomode *vmp) 634 { 635 struct vesagtf_params params; 636 637 params.margin_ppt = VESAGTF_MARGIN_PPT; 638 params.min_porch = VESAGTF_MIN_PORCH; 639 params.vsync_rqd = VESAGTF_VSYNC_RQD; 640 params.hsync_pct = VESAGTF_HSYNC_PCT; 641 params.min_vsbp = VESAGTF_MIN_VSBP; 642 params.M = VESAGTF_M; 643 params.C = VESAGTF_C; 644 params.K = VESAGTF_K; 645 params.J = VESAGTF_J; 646 647 vesagtf_mode_params(x, y, refresh, ¶ms, 0, vmp); 648 } 649 650 /* 651 * The tidbit here is so that you can compile this file as a 652 * standalone user program to generate X11 modelines using VESA GTF. 653 * This also allows for testing of the code itself, without 654 * necessitating a full kernel recompile. 655 */ 656 657 /* print_xf86_mode() - print the XFree86 modeline, given mode timings. */ 658 659 #if 0 660 #ifndef _KERNEL 661 void 662 print_xf86_mode (struct videomode *vmp) 663 { 664 float vf, hf; 665 666 hf = 1000.0 * vmp->dot_clock / vmp->htotal; 667 vf = 1.0 * hf / vmp->vtotal; 668 669 printf("\n"); 670 printf(" # %dx%d @ %.2f Hz (GTF) hsync: %.2f kHz; pclk: %.2f MHz\n", 671 vmp->hdisplay, vmp->vdisplay, vf, hf, vmp->dot_clock / 1000.0); 672 673 printf(" Modeline \"%dx%d_%.2f\" %.2f" 674 " %d %d %d %d" 675 " %d %d %d %d" 676 " -HSync +Vsync\n\n", 677 vmp->hdisplay, vmp->vdisplay, vf, (vmp->dot_clock / 1000.0), 678 vmp->hdisplay, vmp->hsync_start, vmp->hsync_end, vmp->htotal, 679 vmp->vdisplay, vmp->vsync_start, vmp->vsync_end, vmp->vtotal); 680 } 681 682 int 683 main (int argc, char *argv[]) 684 { 685 struct videomode m; 686 687 if (argc != 4) { 688 printf("usage: %s x y refresh\n", argv[0]); 689 exit(1); 690 } 691 692 vesagtf_mode(atoi(argv[1]), atoi(argv[2]), atoi(argv[3]), &m); 693 694 print_xf86_mode(&m); 695 696 return 0; 697 698 } 699 #endif 700 #endif 701