1 /* $NetBSD: vesagtf.c,v 1.2 2013/09/15 15:56:07 martin Exp $ */ 2 /* $FreeBSD$ */ 3 4 /*- 5 * Copyright (c) 2006 Itronix Inc. 6 * All rights reserved. 7 * 8 * Written by Garrett D'Amore for Itronix Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. The name of Itronix Inc. may not be used to endorse 19 * or promote products derived from this software without specific 20 * prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND ANY EXPRESS 23 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 24 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY 26 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 28 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 31 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 32 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 /* 36 * This was derived from a userland GTF program supplied by NVIDIA. 37 * NVIDIA's original boilerplate follows. 38 * 39 * Note that I have heavily modified the program for use in the EDID 40 * kernel code for NetBSD, including removing the use of floating 41 * point operations and making significant adjustments to minimize 42 * error propagation while operating with integer only math. 43 * 44 * This has required the use of 64-bit integers in a few places, but 45 * the upshot is that for a calculation of 1920x1200x85 (as an 46 * example), the error deviates by only ~.004% relative to the 47 * floating point version. This error is *well* within VESA 48 * tolerances. 49 */ 50 51 /* 52 * Copyright (c) 2001, Andy Ritger aritger@nvidia.com 53 * All rights reserved. 54 * 55 * Redistribution and use in source and binary forms, with or without 56 * modification, are permitted provided that the following conditions 57 * are met: 58 * 59 * o Redistributions of source code must retain the above copyright 60 * notice, this list of conditions and the following disclaimer. 61 * o Redistributions in binary form must reproduce the above copyright 62 * notice, this list of conditions and the following disclaimer 63 * in the documentation and/or other materials provided with the 64 * distribution. 65 * o Neither the name of NVIDIA nor the names of its contributors 66 * may be used to endorse or promote products derived from this 67 * software without specific prior written permission. 68 * 69 * 70 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 71 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT 72 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 73 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 74 * THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 75 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 76 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 77 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 78 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 79 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 80 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 81 * POSSIBILITY OF SUCH DAMAGE. 82 * 83 * 84 * 85 * This program is based on the Generalized Timing Formula(GTF TM) 86 * Standard Version: 1.0, Revision: 1.0 87 * 88 * The GTF Document contains the following Copyright information: 89 * 90 * Copyright (c) 1994, 1995, 1996 - Video Electronics Standards 91 * Association. Duplication of this document within VESA member 92 * companies for review purposes is permitted. All other rights 93 * reserved. 94 * 95 * While every precaution has been taken in the preparation 96 * of this standard, the Video Electronics Standards Association and 97 * its contributors assume no responsibility for errors or omissions, 98 * and make no warranties, expressed or implied, of functionality 99 * of suitability for any purpose. The sample code contained within 100 * this standard may be used without restriction. 101 * 102 * 103 * 104 * The GTF EXCEL(TM) SPREADSHEET, a sample (and the definitive) 105 * implementation of the GTF Timing Standard, is available at: 106 * 107 * ftp://ftp.vesa.org/pub/GTF/GTF_V1R1.xls 108 * 109 * 110 * 111 * This program takes a desired resolution and vertical refresh rate, 112 * and computes mode timings according to the GTF Timing Standard. 113 * These mode timings can then be formatted as an XFree86 modeline 114 * or a mode description for use by fbset(8). 115 * 116 * 117 * 118 * NOTES: 119 * 120 * The GTF allows for computation of "margins" (the visible border 121 * surrounding the addressable video); on most non-overscan type 122 * systems, the margin period is zero. I've implemented the margin 123 * computations but not enabled it because 1) I don't really have 124 * any experience with this, and 2) neither XFree86 modelines nor 125 * fbset fb.modes provide an obvious way for margin timings to be 126 * included in their mode descriptions (needs more investigation). 127 * 128 * The GTF provides for computation of interlaced mode timings; 129 * I've implemented the computations but not enabled them, yet. 130 * I should probably enable and test this at some point. 131 * 132 * 133 * 134 * TODO: 135 * 136 * o Add support for interlaced modes. 137 * 138 * o Implement the other portions of the GTF: compute mode timings 139 * given either the desired pixel clock or the desired horizontal 140 * frequency. 141 * 142 * o It would be nice if this were more general purpose to do things 143 * outside the scope of the GTF: like generate double scan mode 144 * timings, for example. 145 * 146 * o Printing digits to the right of the decimal point when the 147 * digits are 0 annoys me. 148 * 149 * o Error checking. 150 * 151 */ 152 153 #ifdef _KERNEL 154 #include <sys/cdefs.h> 155 156 __FBSDID("$FreeBSD$"); 157 #include <sys/types.h> 158 #include <sys/param.h> 159 #include <sys/systm.h> 160 #include <dev/videomode/videomode.h> 161 #include <dev/videomode/vesagtf.h> 162 #else 163 #include <stdio.h> 164 #include <stdlib.h> 165 #include <sys/types.h> 166 #include "videomode.h" 167 #include "vesagtf.h" 168 169 void print_xf86_mode(struct videomode *m); 170 #endif 171 172 #define CELL_GRAN 8 /* assumed character cell granularity */ 173 174 /* C' and M' are part of the Blanking Duty Cycle computation */ 175 /* 176 * #define C_PRIME (((C - J) * K/256.0) + J) 177 * #define M_PRIME (K/256.0 * M) 178 */ 179 180 /* 181 * C' and M' multiplied by 256 to give integer math. Make sure to 182 * scale results using these back down, appropriately. 183 */ 184 #define C_PRIME256(p) (((p->C - p->J) * p->K) + (p->J * 256)) 185 #define M_PRIME256(p) (p->K * p->M) 186 187 #define DIVIDE(x,y) (((x) + ((y) / 2)) / (y)) 188 189 /* 190 * print_value() - print the result of the named computation; this is 191 * useful when comparing against the GTF EXCEL spreadsheet. 192 */ 193 194 #ifdef GTFDEBUG 195 196 static void 197 print_value(int n, const char *name, unsigned val) 198 { 199 printf("%2d: %-27s: %u\n", n, name, val); 200 } 201 #else 202 #define print_value(n, name, val) 203 #endif 204 205 /* 206 * vert_refresh() - as defined by the GTF Timing Standard, compute the 207 * Stage 1 Parameters using the vertical refresh frequency. In other 208 * words: input a desired resolution and desired refresh rate, and 209 * output the GTF mode timings. 210 * 211 * XXX All the code is in place to compute interlaced modes, but I don't 212 * feel like testing it right now. 213 * 214 * XXX margin computations are implemented but not tested (nor used by 215 * XFree86 of fbset mode descriptions, from what I can tell). 216 */ 217 218 void 219 vesagtf_mode_params(unsigned h_pixels, unsigned v_lines, unsigned freq, 220 struct vesagtf_params *params, int flags, struct videomode *vmp) 221 { 222 unsigned v_field_rqd; 223 unsigned top_margin; 224 unsigned bottom_margin; 225 unsigned interlace; 226 uint64_t h_period_est; 227 unsigned vsync_plus_bp; 228 unsigned v_back_porch __unused; 229 unsigned total_v_lines; 230 uint64_t v_field_est; 231 uint64_t h_period; 232 unsigned v_field_rate; 233 unsigned v_frame_rate __unused; 234 unsigned left_margin; 235 unsigned right_margin; 236 unsigned total_active_pixels; 237 uint64_t ideal_duty_cycle; 238 unsigned h_blank; 239 unsigned total_pixels; 240 unsigned pixel_freq; 241 242 unsigned h_sync; 243 unsigned h_front_porch; 244 unsigned v_odd_front_porch_lines; 245 246 #ifdef GTFDEBUG 247 unsigned h_freq; 248 #endif 249 250 /* 1. In order to give correct results, the number of horizontal 251 * pixels requested is first processed to ensure that it is divisible 252 * by the character size, by rounding it to the nearest character 253 * cell boundary: 254 * 255 * [H PIXELS RND] = ((ROUND([H PIXELS]/[CELL GRAN RND],0))*[CELLGRAN RND]) 256 */ 257 258 h_pixels = DIVIDE(h_pixels, CELL_GRAN) * CELL_GRAN; 259 260 print_value(1, "[H PIXELS RND]", h_pixels); 261 262 263 /* 2. If interlace is requested, the number of vertical lines assumed 264 * by the calculation must be halved, as the computation calculates 265 * the number of vertical lines per field. In either case, the 266 * number of lines is rounded to the nearest integer. 267 * 268 * [V LINES RND] = IF([INT RQD?]="y", ROUND([V LINES]/2,0), 269 * ROUND([V LINES],0)) 270 */ 271 272 v_lines = (flags & VESAGTF_FLAG_ILACE) ? DIVIDE(v_lines, 2) : v_lines; 273 274 print_value(2, "[V LINES RND]", v_lines); 275 276 277 /* 3. Find the frame rate required: 278 * 279 * [V FIELD RATE RQD] = IF([INT RQD?]="y", [I/P FREQ RQD]*2, 280 * [I/P FREQ RQD]) 281 */ 282 283 v_field_rqd = (flags & VESAGTF_FLAG_ILACE) ? (freq * 2) : (freq); 284 285 print_value(3, "[V FIELD RATE RQD]", v_field_rqd); 286 287 288 /* 4. Find number of lines in Top margin: 289 * 5. Find number of lines in Bottom margin: 290 * 291 * [TOP MARGIN (LINES)] = IF([MARGINS RQD?]="Y", 292 * ROUND(([MARGIN%]/100*[V LINES RND]),0), 293 * 0) 294 * 295 * Ditto for bottom margin. Note that instead of %, we use PPT, which 296 * is parts per thousand. This helps us with integer math. 297 */ 298 299 top_margin = bottom_margin = (flags & VESAGTF_FLAG_MARGINS) ? 300 DIVIDE(v_lines * params->margin_ppt, 1000) : 0; 301 302 print_value(4, "[TOP MARGIN (LINES)]", top_margin); 303 print_value(5, "[BOT MARGIN (LINES)]", bottom_margin); 304 305 306 /* 6. If interlace is required, then set variable [INTERLACE]=0.5: 307 * 308 * [INTERLACE]=(IF([INT RQD?]="y",0.5,0)) 309 * 310 * To make this integer friendly, we use some special hacks in step 311 * 7 below. Please read those comments to understand why I am using 312 * a whole number of 1.0 instead of 0.5 here. 313 */ 314 interlace = (flags & VESAGTF_FLAG_ILACE) ? 1 : 0; 315 316 print_value(6, "[2*INTERLACE]", interlace); 317 318 319 /* 7. Estimate the Horizontal period 320 * 321 * [H PERIOD EST] = ((1/[V FIELD RATE RQD]) - [MIN VSYNC+BP]/1000000) / 322 * ([V LINES RND] + (2*[TOP MARGIN (LINES)]) + 323 * [MIN PORCH RND]+[INTERLACE]) * 1000000 324 * 325 * To make it integer friendly, we pre-multiply the 1000000 to get to 326 * usec. This gives us: 327 * 328 * [H PERIOD EST] = ((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP]) / 329 * ([V LINES RND] + (2 * [TOP MARGIN (LINES)]) + 330 * [MIN PORCH RND]+[INTERLACE]) 331 * 332 * The other problem is that the interlace value is wrong. To get 333 * the interlace to a whole number, we multiply both the numerator and 334 * divisor by 2, so we can use a value of either 1 or 0 for the interlace 335 * factor. 336 * 337 * This gives us: 338 * 339 * [H PERIOD EST] = ((2*((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP])) / 340 * (2*([V LINES RND] + (2*[TOP MARGIN (LINES)]) + 341 * [MIN PORCH RND]) + [2*INTERLACE])) 342 * 343 * Finally we multiply by another 1000, to get value in picosec. 344 * Why picosec? To minimize rounding errors. Gotta love integer 345 * math and error propagation. 346 */ 347 348 h_period_est = DIVIDE(((DIVIDE(2000000000000ULL, v_field_rqd)) - 349 (2000000 * params->min_vsbp)), 350 ((2 * (v_lines + (2 * top_margin) + params->min_porch)) + interlace)); 351 352 print_value(7, "[H PERIOD EST (ps)]", h_period_est); 353 354 355 /* 8. Find the number of lines in V sync + back porch: 356 * 357 * [V SYNC+BP] = ROUND(([MIN VSYNC+BP]/[H PERIOD EST]),0) 358 * 359 * But recall that h_period_est is in psec. So multiply by 1000000. 360 */ 361 362 vsync_plus_bp = DIVIDE(params->min_vsbp * 1000000, h_period_est); 363 364 print_value(8, "[V SYNC+BP]", vsync_plus_bp); 365 366 367 /* 9. Find the number of lines in V back porch alone: 368 * 369 * [V BACK PORCH] = [V SYNC+BP] - [V SYNC RND] 370 * 371 * XXX is "[V SYNC RND]" a typo? should be [V SYNC RQD]? 372 */ 373 374 v_back_porch = vsync_plus_bp - params->vsync_rqd; 375 376 print_value(9, "[V BACK PORCH]", v_back_porch); 377 378 379 /* 10. Find the total number of lines in Vertical field period: 380 * 381 * [TOTAL V LINES] = [V LINES RND] + [TOP MARGIN (LINES)] + 382 * [BOT MARGIN (LINES)] + [V SYNC+BP] + [INTERLACE] + 383 * [MIN PORCH RND] 384 */ 385 386 total_v_lines = v_lines + top_margin + bottom_margin + vsync_plus_bp + 387 interlace + params->min_porch; 388 389 print_value(10, "[TOTAL V LINES]", total_v_lines); 390 391 392 /* 11. Estimate the Vertical field frequency: 393 * 394 * [V FIELD RATE EST] = 1 / [H PERIOD EST] / [TOTAL V LINES] * 1000000 395 * 396 * Again, we want to pre multiply by 10^9 to convert for nsec, thereby 397 * making it usable in integer math. 398 * 399 * So we get: 400 * 401 * [V FIELD RATE EST] = 1000000000 / [H PERIOD EST] / [TOTAL V LINES] 402 * 403 * This is all scaled to get the result in uHz. Again, we're trying to 404 * minimize error propagation. 405 */ 406 v_field_est = DIVIDE(DIVIDE(1000000000000000ULL, h_period_est), 407 total_v_lines); 408 409 print_value(11, "[V FIELD RATE EST(uHz)]", v_field_est); 410 411 412 /* 12. Find the actual horizontal period: 413 * 414 * [H PERIOD] = [H PERIOD EST] / ([V FIELD RATE RQD] / [V FIELD RATE EST]) 415 */ 416 417 h_period = DIVIDE(h_period_est * v_field_est, v_field_rqd * 1000); 418 419 print_value(12, "[H PERIOD(ps)]", h_period); 420 421 422 /* 13. Find the actual Vertical field frequency: 423 * 424 * [V FIELD RATE] = 1 / [H PERIOD] / [TOTAL V LINES] * 1000000 425 * 426 * And again, we convert to nsec ahead of time, giving us: 427 * 428 * [V FIELD RATE] = 1000000 / [H PERIOD] / [TOTAL V LINES] 429 * 430 * And another rescaling back to mHz. Gotta love it. 431 */ 432 433 v_field_rate = DIVIDE(1000000000000ULL, h_period * total_v_lines); 434 435 print_value(13, "[V FIELD RATE]", v_field_rate); 436 437 438 /* 14. Find the Vertical frame frequency: 439 * 440 * [V FRAME RATE] = (IF([INT RQD?]="y", [V FIELD RATE]/2, [V FIELD RATE])) 441 * 442 * N.B. that the result here is in mHz. 443 */ 444 445 v_frame_rate = (flags & VESAGTF_FLAG_ILACE) ? 446 v_field_rate / 2 : v_field_rate; 447 448 print_value(14, "[V FRAME RATE]", v_frame_rate); 449 450 451 /* 15. Find number of pixels in left margin: 452 * 16. Find number of pixels in right margin: 453 * 454 * [LEFT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y", 455 * (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 / 456 * [CELL GRAN RND]),0)) * [CELL GRAN RND], 457 * 0)) 458 * 459 * Again, we deal with margin percentages as PPT (parts per thousand). 460 * And the calculations for left and right are the same. 461 */ 462 463 left_margin = right_margin = (flags & VESAGTF_FLAG_MARGINS) ? 464 DIVIDE(DIVIDE(h_pixels * params->margin_ppt, 1000), 465 CELL_GRAN) * CELL_GRAN : 0; 466 467 print_value(15, "[LEFT MARGIN (PIXELS)]", left_margin); 468 print_value(16, "[RIGHT MARGIN (PIXELS)]", right_margin); 469 470 471 /* 17. Find total number of active pixels in image and left and right 472 * margins: 473 * 474 * [TOTAL ACTIVE PIXELS] = [H PIXELS RND] + [LEFT MARGIN (PIXELS)] + 475 * [RIGHT MARGIN (PIXELS)] 476 */ 477 478 total_active_pixels = h_pixels + left_margin + right_margin; 479 480 print_value(17, "[TOTAL ACTIVE PIXELS]", total_active_pixels); 481 482 483 /* 18. Find the ideal blanking duty cycle from the blanking duty cycle 484 * equation: 485 * 486 * [IDEAL DUTY CYCLE] = [C'] - ([M']*[H PERIOD]/1000) 487 * 488 * However, we have modified values for [C'] as [256*C'] and 489 * [M'] as [256*M']. Again the idea here is to get good scaling. 490 * We use 256 as the factor to make the math fast. 491 * 492 * Note that this means that we have to scale it appropriately in 493 * later calculations. 494 * 495 * The ending result is that our ideal_duty_cycle is 256000x larger 496 * than the duty cycle used by VESA. But again, this reduces error 497 * propagation. 498 */ 499 500 ideal_duty_cycle = 501 ((C_PRIME256(params) * 1000) - 502 (M_PRIME256(params) * h_period / 1000000)); 503 504 print_value(18, "[IDEAL DUTY CYCLE]", ideal_duty_cycle); 505 506 507 /* 19. Find the number of pixels in the blanking time to the nearest 508 * double character cell: 509 * 510 * [H BLANK (PIXELS)] = (ROUND(([TOTAL ACTIVE PIXELS] * 511 * [IDEAL DUTY CYCLE] / 512 * (100-[IDEAL DUTY CYCLE]) / 513 * (2*[CELL GRAN RND])), 0)) 514 * * (2*[CELL GRAN RND]) 515 * 516 * Of course, we adjust to make this rounding work in integer math. 517 */ 518 519 h_blank = DIVIDE(DIVIDE(total_active_pixels * ideal_duty_cycle, 520 (256000 * 100ULL) - ideal_duty_cycle), 521 2 * CELL_GRAN) * (2 * CELL_GRAN); 522 523 print_value(19, "[H BLANK (PIXELS)]", h_blank); 524 525 526 /* 20. Find total number of pixels: 527 * 528 * [TOTAL PIXELS] = [TOTAL ACTIVE PIXELS] + [H BLANK (PIXELS)] 529 */ 530 531 total_pixels = total_active_pixels + h_blank; 532 533 print_value(20, "[TOTAL PIXELS]", total_pixels); 534 535 536 /* 21. Find pixel clock frequency: 537 * 538 * [PIXEL FREQ] = [TOTAL PIXELS] / [H PERIOD] 539 * 540 * We calculate this in Hz rather than MHz, to get a value that 541 * is usable with integer math. Recall that the [H PERIOD] is in 542 * nsec. 543 */ 544 545 pixel_freq = DIVIDE(total_pixels * 1000000, DIVIDE(h_period, 1000)); 546 547 print_value(21, "[PIXEL FREQ]", pixel_freq); 548 549 550 /* 22. Find horizontal frequency: 551 * 552 * [H FREQ] = 1000 / [H PERIOD] 553 * 554 * I've ifdef'd this out, because we don't need it for any of 555 * our calculations. 556 * We calculate this in Hz rather than kHz, to avoid rounding 557 * errors. Recall that the [H PERIOD] is in usec. 558 */ 559 560 #ifdef GTFDEBUG 561 h_freq = 1000000000 / h_period; 562 563 print_value(22, "[H FREQ]", h_freq); 564 #endif 565 566 567 /* Stage 1 computations are now complete; I should really pass 568 the results to another function and do the Stage 2 569 computations, but I only need a few more values so I'll just 570 append the computations here for now */ 571 572 573 574 /* 17. Find the number of pixels in the horizontal sync period: 575 * 576 * [H SYNC (PIXELS)] =(ROUND(([H SYNC%] / 100 * [TOTAL PIXELS] / 577 * [CELL GRAN RND]),0))*[CELL GRAN RND] 578 * 579 * Rewriting for integer math: 580 * 581 * [H SYNC (PIXELS)]=(ROUND((H SYNC%] * [TOTAL PIXELS] / 100 / 582 * [CELL GRAN RND),0))*[CELL GRAN RND] 583 */ 584 585 h_sync = DIVIDE(((params->hsync_pct * total_pixels) / 100), CELL_GRAN) * 586 CELL_GRAN; 587 588 print_value(17, "[H SYNC (PIXELS)]", h_sync); 589 590 591 /* 18. Find the number of pixels in the horizontal front porch period: 592 * 593 * [H FRONT PORCH (PIXELS)] = ([H BLANK (PIXELS)]/2)-[H SYNC (PIXELS)] 594 * 595 * Note that h_blank is always an even number of characters (i.e. 596 * h_blank % (CELL_GRAN * 2) == 0) 597 */ 598 599 h_front_porch = (h_blank / 2) - h_sync; 600 601 print_value(18, "[H FRONT PORCH (PIXELS)]", h_front_porch); 602 603 604 /* 36. Find the number of lines in the odd front porch period: 605 * 606 * [V ODD FRONT PORCH(LINES)]=([MIN PORCH RND]+[INTERLACE]) 607 * 608 * Adjusting for the fact that the interlace is scaled: 609 * 610 * [V ODD FRONT PORCH(LINES)]=(([MIN PORCH RND] * 2) + [2*INTERLACE]) / 2 611 */ 612 613 v_odd_front_porch_lines = ((2 * params->min_porch) + interlace) / 2; 614 615 print_value(36, "[V ODD FRONT PORCH(LINES)]", v_odd_front_porch_lines); 616 617 618 /* finally, pack the results in the mode struct */ 619 620 vmp->hsync_start = h_pixels + h_front_porch; 621 vmp->hsync_end = vmp->hsync_start + h_sync; 622 vmp->htotal = total_pixels; 623 vmp->hdisplay = h_pixels; 624 625 vmp->vsync_start = v_lines + v_odd_front_porch_lines; 626 vmp->vsync_end = vmp->vsync_start + params->vsync_rqd; 627 vmp->vtotal = total_v_lines; 628 vmp->vdisplay = v_lines; 629 630 vmp->dot_clock = pixel_freq; 631 632 } 633 634 void 635 vesagtf_mode(unsigned x, unsigned y, unsigned refresh, struct videomode *vmp) 636 { 637 struct vesagtf_params params; 638 639 params.margin_ppt = VESAGTF_MARGIN_PPT; 640 params.min_porch = VESAGTF_MIN_PORCH; 641 params.vsync_rqd = VESAGTF_VSYNC_RQD; 642 params.hsync_pct = VESAGTF_HSYNC_PCT; 643 params.min_vsbp = VESAGTF_MIN_VSBP; 644 params.M = VESAGTF_M; 645 params.C = VESAGTF_C; 646 params.K = VESAGTF_K; 647 params.J = VESAGTF_J; 648 649 vesagtf_mode_params(x, y, refresh, ¶ms, 0, vmp); 650 } 651 652 /* 653 * The tidbit here is so that you can compile this file as a 654 * standalone user program to generate X11 modelines using VESA GTF. 655 * This also allows for testing of the code itself, without 656 * necessitating a full kernel recompile. 657 */ 658 659 /* print_xf86_mode() - print the XFree86 modeline, given mode timings. */ 660 661 #ifndef _KERNEL 662 void 663 print_xf86_mode (struct videomode *vmp) 664 { 665 float vf, hf; 666 667 hf = 1000.0 * vmp->dot_clock / vmp->htotal; 668 vf = 1.0 * hf / vmp->vtotal; 669 670 printf("\n"); 671 printf(" # %dx%d @ %.2f Hz (GTF) hsync: %.2f kHz; pclk: %.2f MHz\n", 672 vmp->hdisplay, vmp->vdisplay, vf, hf, vmp->dot_clock / 1000.0); 673 674 printf(" Modeline \"%dx%d_%.2f\" %.2f" 675 " %d %d %d %d" 676 " %d %d %d %d" 677 " -HSync +Vsync\n\n", 678 vmp->hdisplay, vmp->vdisplay, vf, (vmp->dot_clock / 1000.0), 679 vmp->hdisplay, vmp->hsync_start, vmp->hsync_end, vmp->htotal, 680 vmp->vdisplay, vmp->vsync_start, vmp->vsync_end, vmp->vtotal); 681 } 682 683 int 684 main (int argc, char *argv[]) 685 { 686 struct videomode m; 687 688 if (argc != 4) { 689 printf("usage: %s x y refresh\n", argv[0]); 690 exit(1); 691 } 692 693 vesagtf_mode(atoi(argv[1]), atoi(argv[2]), atoi(argv[3]), &m); 694 695 print_xf86_mode(&m); 696 697 return 0; 698 699 } 700 #endif 701