1 /* $NetBSD: vesagtf.c,v 1.1 2006/05/11 01:49:53 gdamore 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 propogation 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 1.1 2006/05/11 01:49:53 gdamore Exp $"); 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 /* 207 * vert_refresh() - as defined by the GTF Timing Standard, compute the 208 * Stage 1 Parameters using the vertical refresh frequency. In other 209 * words: input a desired resolution and desired refresh rate, and 210 * output the GTF mode timings. 211 * 212 * XXX All the code is in place to compute interlaced modes, but I don't 213 * feel like testing it right now. 214 * 215 * XXX margin computations are implemented but not tested (nor used by 216 * XFree86 of fbset mode descriptions, from what I can tell). 217 */ 218 219 void 220 vesagtf_mode_params(unsigned h_pixels, unsigned v_lines, unsigned freq, 221 struct vesagtf_params *params, int flags, struct videomode *vmp) 222 { 223 unsigned v_field_rqd; 224 unsigned top_margin; 225 unsigned bottom_margin; 226 unsigned interlace; 227 uint64_t h_period_est; 228 unsigned vsync_plus_bp; 229 unsigned v_back_porch; 230 unsigned total_v_lines; 231 uint64_t v_field_est; 232 uint64_t h_period; 233 unsigned v_field_rate; 234 unsigned v_frame_rate; 235 unsigned left_margin; 236 unsigned right_margin; 237 unsigned total_active_pixels; 238 uint64_t ideal_duty_cycle; 239 unsigned h_blank; 240 unsigned total_pixels; 241 unsigned pixel_freq; 242 243 unsigned h_sync; 244 unsigned h_front_porch; 245 unsigned v_odd_front_porch_lines; 246 247 #ifdef GTFDEBUG 248 unsigned h_freq; 249 #endif 250 251 /* 1. In order to give correct results, the number of horizontal 252 * pixels requested is first processed to ensure that it is divisible 253 * by the character size, by rounding it to the nearest character 254 * cell boundary: 255 * 256 * [H PIXELS RND] = ((ROUND([H PIXELS]/[CELL GRAN RND],0))*[CELLGRAN RND]) 257 */ 258 259 h_pixels = DIVIDE(h_pixels, CELL_GRAN) * CELL_GRAN; 260 261 print_value(1, "[H PIXELS RND]", h_pixels); 262 263 264 /* 2. If interlace is requested, the number of vertical lines assumed 265 * by the calculation must be halved, as the computation calculates 266 * the number of vertical lines per field. In either case, the 267 * number of lines is rounded to the nearest integer. 268 * 269 * [V LINES RND] = IF([INT RQD?]="y", ROUND([V LINES]/2,0), 270 * ROUND([V LINES],0)) 271 */ 272 273 v_lines = (flags & VESAGTF_FLAG_ILACE) ? DIVIDE(v_lines, 2) : v_lines; 274 275 print_value(2, "[V LINES RND]", v_lines); 276 277 278 /* 3. Find the frame rate required: 279 * 280 * [V FIELD RATE RQD] = IF([INT RQD?]="y", [I/P FREQ RQD]*2, 281 * [I/P FREQ RQD]) 282 */ 283 284 v_field_rqd = (flags & VESAGTF_FLAG_ILACE) ? (freq * 2) : (freq); 285 286 print_value(3, "[V FIELD RATE RQD]", v_field_rqd); 287 288 289 /* 4. Find number of lines in Top margin: 290 * 5. Find number of lines in Bottom margin: 291 * 292 * [TOP MARGIN (LINES)] = IF([MARGINS RQD?]="Y", 293 * ROUND(([MARGIN%]/100*[V LINES RND]),0), 294 * 0) 295 * 296 * Ditto for bottom margin. Note that instead of %, we use PPT, which 297 * is parts per thousand. This helps us with integer math. 298 */ 299 300 top_margin = bottom_margin = (flags & VESAGTF_FLAG_MARGINS) ? 301 DIVIDE(v_lines * params->margin_ppt, 1000) : 0; 302 303 print_value(4, "[TOP MARGIN (LINES)]", top_margin); 304 print_value(5, "[BOT MARGIN (LINES)]", bottom_margin); 305 306 307 /* 6. If interlace is required, then set variable [INTERLACE]=0.5: 308 * 309 * [INTERLACE]=(IF([INT RQD?]="y",0.5,0)) 310 * 311 * To make this integer friendly, we use some special hacks in step 312 * 7 below. Please read those comments to understand why I am using 313 * a whole number of 1.0 instead of 0.5 here. 314 */ 315 interlace = (flags & VESAGTF_FLAG_ILACE) ? 1 : 0; 316 317 print_value(6, "[2*INTERLACE]", interlace); 318 319 320 /* 7. Estimate the Horizontal period 321 * 322 * [H PERIOD EST] = ((1/[V FIELD RATE RQD]) - [MIN VSYNC+BP]/1000000) / 323 * ([V LINES RND] + (2*[TOP MARGIN (LINES)]) + 324 * [MIN PORCH RND]+[INTERLACE]) * 1000000 325 * 326 * To make it integer friendly, we pre-multiply the 1000000 to get to 327 * usec. This gives us: 328 * 329 * [H PERIOD EST] = ((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP]) / 330 * ([V LINES RND] + (2 * [TOP MARGIN (LINES)]) + 331 * [MIN PORCH RND]+[INTERLACE]) 332 * 333 * The other problem is that the interlace value is wrong. To get 334 * the interlace to a whole number, we multiply both the numerator and 335 * divisor by 2, so we can use a value of either 1 or 0 for the interlace 336 * factor. 337 * 338 * This gives us: 339 * 340 * [H PERIOD EST] = ((2*((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP])) / 341 * (2*([V LINES RND] + (2*[TOP MARGIN (LINES)]) + 342 * [MIN PORCH RND]) + [2*INTERLACE])) 343 * 344 * Finally we multiply by another 1000, to get value in picosec. 345 * Why picosec? To minimize rounding errors. Gotta love integer 346 * math and error propogation. 347 */ 348 349 h_period_est = DIVIDE(((DIVIDE(2000000000000ULL, v_field_rqd)) - 350 (2000000 * params->min_vsbp)), 351 ((2 * (v_lines + (2 * top_margin) + params->min_porch)) + interlace)); 352 353 print_value(7, "[H PERIOD EST (ps)]", h_period_est); 354 355 356 /* 8. Find the number of lines in V sync + back porch: 357 * 358 * [V SYNC+BP] = ROUND(([MIN VSYNC+BP]/[H PERIOD EST]),0) 359 * 360 * But recall that h_period_est is in psec. So multiply by 1000000. 361 */ 362 363 vsync_plus_bp = DIVIDE(params->min_vsbp * 1000000, h_period_est); 364 365 print_value(8, "[V SYNC+BP]", vsync_plus_bp); 366 367 368 /* 9. Find the number of lines in V back porch alone: 369 * 370 * [V BACK PORCH] = [V SYNC+BP] - [V SYNC RND] 371 * 372 * XXX is "[V SYNC RND]" a typo? should be [V SYNC RQD]? 373 */ 374 375 v_back_porch = vsync_plus_bp - params->vsync_rqd; 376 377 print_value(9, "[V BACK PORCH]", v_back_porch); 378 379 380 /* 10. Find the total number of lines in Vertical field period: 381 * 382 * [TOTAL V LINES] = [V LINES RND] + [TOP MARGIN (LINES)] + 383 * [BOT MARGIN (LINES)] + [V SYNC+BP] + [INTERLACE] + 384 * [MIN PORCH RND] 385 */ 386 387 total_v_lines = v_lines + top_margin + bottom_margin + vsync_plus_bp + 388 interlace + params->min_porch; 389 390 print_value(10, "[TOTAL V LINES]", total_v_lines); 391 392 393 /* 11. Estimate the Vertical field frequency: 394 * 395 * [V FIELD RATE EST] = 1 / [H PERIOD EST] / [TOTAL V LINES] * 1000000 396 * 397 * Again, we want to pre multiply by 10^9 to convert for nsec, thereby 398 * making it usable in integer math. 399 * 400 * So we get: 401 * 402 * [V FIELD RATE EST] = 1000000000 / [H PERIOD EST] / [TOTAL V LINES] 403 * 404 * This is all scaled to get the result in uHz. Again, we're trying to 405 * minimize error propogation. 406 */ 407 v_field_est = DIVIDE(DIVIDE(1000000000000000ULL, h_period_est), 408 total_v_lines); 409 410 print_value(11, "[V FIELD RATE EST(uHz)]", v_field_est); 411 412 413 /* 12. Find the actual horizontal period: 414 * 415 * [H PERIOD] = [H PERIOD EST] / ([V FIELD RATE RQD] / [V FIELD RATE EST]) 416 */ 417 418 h_period = DIVIDE(h_period_est * v_field_est, v_field_rqd * 1000); 419 420 print_value(12, "[H PERIOD(ps)]", h_period); 421 422 423 /* 13. Find the actual Vertical field frequency: 424 * 425 * [V FIELD RATE] = 1 / [H PERIOD] / [TOTAL V LINES] * 1000000 426 * 427 * And again, we convert to nsec ahead of time, giving us: 428 * 429 * [V FIELD RATE] = 1000000 / [H PERIOD] / [TOTAL V LINES] 430 * 431 * And another rescaling back to mHz. Gotta love it. 432 */ 433 434 v_field_rate = DIVIDE(1000000000000ULL, h_period * total_v_lines); 435 436 print_value(13, "[V FIELD RATE]", v_field_rate); 437 438 439 /* 14. Find the Vertical frame frequency: 440 * 441 * [V FRAME RATE] = (IF([INT RQD?]="y", [V FIELD RATE]/2, [V FIELD RATE])) 442 * 443 * N.B. that the result here is in mHz. 444 */ 445 446 v_frame_rate = (flags & VESAGTF_FLAG_ILACE) ? 447 v_field_rate / 2 : v_field_rate; 448 449 print_value(14, "[V FRAME RATE]", v_frame_rate); 450 451 452 /* 15. Find number of pixels in left margin: 453 * 16. Find number of pixels in right margin: 454 * 455 * [LEFT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y", 456 * (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 / 457 * [CELL GRAN RND]),0)) * [CELL GRAN RND], 458 * 0)) 459 * 460 * Again, we deal with margin percentages as PPT (parts per thousand). 461 * And the calculations for left and right are the same. 462 */ 463 464 left_margin = right_margin = (flags & VESAGTF_FLAG_MARGINS) ? 465 DIVIDE(DIVIDE(h_pixels * params->margin_ppt, 1000), 466 CELL_GRAN) * CELL_GRAN : 0; 467 468 print_value(15, "[LEFT MARGIN (PIXELS)]", left_margin); 469 print_value(16, "[RIGHT MARGIN (PIXELS)]", right_margin); 470 471 472 /* 17. Find total number of active pixels in image and left and right 473 * margins: 474 * 475 * [TOTAL ACTIVE PIXELS] = [H PIXELS RND] + [LEFT MARGIN (PIXELS)] + 476 * [RIGHT MARGIN (PIXELS)] 477 */ 478 479 total_active_pixels = h_pixels + left_margin + right_margin; 480 481 print_value(17, "[TOTAL ACTIVE PIXELS]", total_active_pixels); 482 483 484 /* 18. Find the ideal blanking duty cycle from the blanking duty cycle 485 * equation: 486 * 487 * [IDEAL DUTY CYCLE] = [C'] - ([M']*[H PERIOD]/1000) 488 * 489 * However, we have modified values for [C'] as [256*C'] and 490 * [M'] as [256*M']. Again the idea here is to get good scaling. 491 * We use 256 as the factor to make the math fast. 492 * 493 * Note that this means that we have to scale it appropriately in 494 * later calculations. 495 * 496 * The ending result is that our ideal_duty_cycle is 256000x larger 497 * than the duty cycle used by VESA. But again, this reduces error 498 * propogation. 499 */ 500 501 ideal_duty_cycle = 502 ((C_PRIME256(params) * 1000) - 503 (M_PRIME256(params) * h_period / 1000000)); 504 505 print_value(18, "[IDEAL DUTY CYCLE]", ideal_duty_cycle); 506 507 508 /* 19. Find the number of pixels in the blanking time to the nearest 509 * double character cell: 510 * 511 * [H BLANK (PIXELS)] = (ROUND(([TOTAL ACTIVE PIXELS] * 512 * [IDEAL DUTY CYCLE] / 513 * (100-[IDEAL DUTY CYCLE]) / 514 * (2*[CELL GRAN RND])), 0)) 515 * * (2*[CELL GRAN RND]) 516 * 517 * Of course, we adjust to make this rounding work in integer math. 518 */ 519 520 h_blank = DIVIDE(DIVIDE(total_active_pixels * ideal_duty_cycle, 521 (256000 * 100ULL) - ideal_duty_cycle), 522 2 * CELL_GRAN) * (2 * CELL_GRAN); 523 524 print_value(19, "[H BLANK (PIXELS)]", h_blank); 525 526 527 /* 20. Find total number of pixels: 528 * 529 * [TOTAL PIXELS] = [TOTAL ACTIVE PIXELS] + [H BLANK (PIXELS)] 530 */ 531 532 total_pixels = total_active_pixels + h_blank; 533 534 print_value(20, "[TOTAL PIXELS]", total_pixels); 535 536 537 /* 21. Find pixel clock frequency: 538 * 539 * [PIXEL FREQ] = [TOTAL PIXELS] / [H PERIOD] 540 * 541 * We calculate this in Hz rather than MHz, to get a value that 542 * is usable with integer math. Recall that the [H PERIOD] is in 543 * nsec. 544 */ 545 546 pixel_freq = DIVIDE(total_pixels * 1000000, DIVIDE(h_period, 1000)); 547 548 print_value(21, "[PIXEL FREQ]", pixel_freq); 549 550 551 /* 22. Find horizontal frequency: 552 * 553 * [H FREQ] = 1000 / [H PERIOD] 554 * 555 * I've ifdef'd this out, because we don't need it for any of 556 * our calculations. 557 * We calculate this in Hz rather than kHz, to avoid rounding 558 * errors. Recall that the [H PERIOD] is in usec. 559 */ 560 561 #ifdef GTFDEBUG 562 h_freq = 1000000000 / h_period; 563 564 print_value(22, "[H FREQ]", h_freq); 565 #endif 566 567 568 569 /* Stage 1 computations are now complete; I should really pass 570 the results to another function and do the Stage 2 571 computations, but I only need a few more values so I'll just 572 append the computations here for now */ 573 574 575 576 /* 17. Find the number of pixels in the horizontal sync period: 577 * 578 * [H SYNC (PIXELS)] =(ROUND(([H SYNC%] / 100 * [TOTAL PIXELS] / 579 * [CELL GRAN RND]),0))*[CELL GRAN RND] 580 * 581 * Rewriting for integer math: 582 * 583 * [H SYNC (PIXELS)]=(ROUND((H SYNC%] * [TOTAL PIXELS] / 100 / 584 * [CELL GRAN RND),0))*[CELL GRAN RND] 585 */ 586 587 h_sync = DIVIDE(((params->hsync_pct * total_pixels) / 100), CELL_GRAN) * 588 CELL_GRAN; 589 590 print_value(17, "[H SYNC (PIXELS)]", h_sync); 591 592 593 /* 18. Find the number of pixels in the horizontal front porch period: 594 * 595 * [H FRONT PORCH (PIXELS)] = ([H BLANK (PIXELS)]/2)-[H SYNC (PIXELS)] 596 * 597 * Note that h_blank is always an even number of characters (i.e. 598 * h_blank % (CELL_GRAN * 2) == 0) 599 */ 600 601 h_front_porch = (h_blank / 2) - h_sync; 602 603 print_value(18, "[H FRONT PORCH (PIXELS)]", h_front_porch); 604 605 606 /* 36. Find the number of lines in the odd front porch period: 607 * 608 * [V ODD FRONT PORCH(LINES)]=([MIN PORCH RND]+[INTERLACE]) 609 * 610 * Adjusting for the fact that the interlace is scaled: 611 * 612 * [V ODD FRONT PORCH(LINES)]=(([MIN PORCH RND] * 2) + [2*INTERLACE]) / 2 613 */ 614 615 v_odd_front_porch_lines = ((2 * params->min_porch) + interlace) / 2; 616 617 print_value(36, "[V ODD FRONT PORCH(LINES)]", v_odd_front_porch_lines); 618 619 620 /* finally, pack the results in the mode struct */ 621 622 vmp->hsync_start = h_pixels + h_front_porch; 623 vmp->hsync_end = vmp->hsync_start + h_sync; 624 vmp->htotal = total_pixels; 625 vmp->hdisplay = h_pixels; 626 627 vmp->vsync_start = v_lines + v_odd_front_porch_lines; 628 vmp->vsync_end = vmp->vsync_start + params->vsync_rqd; 629 vmp->vtotal = total_v_lines; 630 vmp->vdisplay = v_lines; 631 632 vmp->dot_clock = pixel_freq; 633 634 } 635 636 void 637 vesagtf_mode(unsigned x, unsigned y, unsigned refresh, struct videomode *vmp) 638 { 639 struct vesagtf_params params; 640 641 params.margin_ppt = VESAGTF_MARGIN_PPT; 642 params.min_porch = VESAGTF_MIN_PORCH; 643 params.vsync_rqd = VESAGTF_VSYNC_RQD; 644 params.hsync_pct = VESAGTF_HSYNC_PCT; 645 params.min_vsbp = VESAGTF_MIN_VSBP; 646 params.M = VESAGTF_M; 647 params.C = VESAGTF_C; 648 params.K = VESAGTF_K; 649 params.J = VESAGTF_J; 650 651 vesagtf_mode_params(x, y, refresh, ¶ms, 0, vmp); 652 } 653 654 /* 655 * The tidbit here is so that you can compile this file as a 656 * standalone user program to generate X11 modelines using VESA GTF. 657 * This also allows for testing of the code itself, without 658 * necessitating a full kernel recompile. 659 */ 660 661 /* print_xf86_mode() - print the XFree86 modeline, given mode timings. */ 662 663 #ifndef _KERNEL 664 void 665 print_xf86_mode (struct videomode *vmp) 666 { 667 float vf, hf; 668 669 hf = 1000.0 * vmp->dot_clock / vmp->htotal; 670 vf = 1.0 * hf / vmp->vtotal; 671 672 printf("\n"); 673 printf(" # %dx%d @ %.2f Hz (GTF) hsync: %.2f kHz; pclk: %.2f MHz\n", 674 vmp->hdisplay, vmp->vdisplay, vf, hf, vmp->dot_clock / 1000.0); 675 676 printf(" Modeline \"%dx%d_%.2f\" %.2f" 677 " %d %d %d %d" 678 " %d %d %d %d" 679 " -HSync +Vsync\n\n", 680 vmp->hdisplay, vmp->vdisplay, vf, (vmp->dot_clock / 1000.0), 681 vmp->hdisplay, vmp->hsync_start, vmp->hsync_end, vmp->htotal, 682 vmp->vdisplay, vmp->vsync_start, vmp->vsync_end, vmp->vtotal); 683 } 684 685 int 686 main (int argc, char *argv[]) 687 { 688 struct videomode m; 689 690 if (argc != 4) { 691 printf("usage: %s x y refresh\n", argv[0]); 692 exit(1); 693 } 694 695 vesagtf_mode(atoi(argv[1]), atoi(argv[2]), atoi(argv[3]), &m); 696 697 print_xf86_mode(&m); 698 699 return 0; 700 701 } 702 #endif 703