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Diffstat (limited to 'hw/xfree86/utils/gtf/gtf.c')
| -rw-r--r-- | hw/xfree86/utils/gtf/gtf.c | 743 |
1 files changed, 743 insertions, 0 deletions
diff --git a/hw/xfree86/utils/gtf/gtf.c b/hw/xfree86/utils/gtf/gtf.c new file mode 100644 index 000000000..b0d9de058 --- /dev/null +++ b/hw/xfree86/utils/gtf/gtf.c @@ -0,0 +1,743 @@ +/* gtf.c Generate mode timings using the GTF Timing Standard + * + * gcc gtf.c -o gtf -lm -Wall + * + * Copyright (c) 2001, Andy Ritger aritger@nvidia.com + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * o Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * o Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * o Neither the name of NVIDIA nor the names of its contributors + * may be used to endorse or promote products derived from this + * software without specific prior written permission. + * + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT + * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL + * THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + * + * + * This program is based on the Generalized Timing Formula(GTF TM) + * Standard Version: 1.0, Revision: 1.0 + * + * The GTF Document contains the following Copyright information: + * + * Copyright (c) 1994, 1995, 1996 - Video Electronics Standards + * Association. Duplication of this document within VESA member + * companies for review purposes is permitted. All other rights + * reserved. + * + * While every precaution has been taken in the preparation + * of this standard, the Video Electronics Standards Association and + * its contributors assume no responsibility for errors or omissions, + * and make no warranties, expressed or implied, of functionality + * of suitability for any purpose. The sample code contained within + * this standard may be used without restriction. + * + * + * + * The GTF EXCEL(TM) SPREADSHEET, a sample (and the definitive) + * implementation of the GTF Timing Standard, is available at: + * + * ftp://ftp.vesa.org/pub/GTF/GTF_V1R1.xls + * + * + * + * This program takes a desired resolution and vertical refresh rate, + * and computes mode timings according to the GTF Timing Standard. + * These mode timings can then be formatted as an XFree86 modeline + * or a mode description for use by fbset(8). + * + * + * + * NOTES: + * + * The GTF allows for computation of "margins" (the visible border + * surrounding the addressable video); on most non-overscan type + * systems, the margin period is zero. I've implemented the margin + * computations but not enabled it because 1) I don't really have + * any experience with this, and 2) neither XFree86 modelines nor + * fbset fb.modes provide an obvious way for margin timings to be + * included in their mode descriptions (needs more investigation). + * + * The GTF provides for computation of interlaced mode timings; + * I've implemented the computations but not enabled them, yet. + * I should probably enable and test this at some point. + * + * + * + * TODO: + * + * o Add support for interlaced modes. + * + * o Implement the other portions of the GTF: compute mode timings + * given either the desired pixel clock or the desired horizontal + * frequency. + * + * o It would be nice if this were more general purpose to do things + * outside the scope of the GTF: like generate double scan mode + * timings, for example. + * + * o Printing digits to the right of the decimal point when the + * digits are 0 annoys me. + * + * o Error checking. + * + */ +/* $XFree86: xc/programs/Xserver/hw/xfree86/etc/gtf.c,v 1.3 2002/12/21 02:35:20 dawes Exp $ */ + + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <math.h> + + +#if defined(__Lynx__) +#define rint(x) floor(x) +#endif + +#define MARGIN_PERCENT 1.8 /* % of active vertical image */ +#define CELL_GRAN 8.0 /* assumed character cell granularity */ +#define MIN_PORCH 1 /* minimum front porch */ +#define V_SYNC_RQD 3 /* width of vsync in lines */ +#define H_SYNC_PERCENT 8.0 /* width of hsync as % of total line */ +#define MIN_VSYNC_PLUS_BP 550.0 /* min time of vsync + back porch (microsec) */ +#define M 600.0 /* blanking formula gradient */ +#define C 40.0 /* blanking formula offset */ +#define K 128.0 /* blanking formula scaling factor */ +#define J 20.0 /* blanking formula scaling factor */ + +/* C' and M' are part of the Blanking Duty Cycle computation */ + +#define C_PRIME (((C - J) * K/256.0) + J) +#define M_PRIME (K/256.0 * M) + + +/* struct definitions */ + +typedef struct __mode +{ + int hr, hss, hse, hfl; + int vr, vss, vse, vfl; + float pclk, h_freq, v_freq; +} mode; + + +typedef struct __options +{ + int x, y; + int xf86mode, fbmode; + float v_freq; +} options; + + + + +/* prototypes */ + +void print_value(int n, char *name, float val); +void print_xf86_mode (mode *m); +void print_fb_mode (mode *m); +mode *vert_refresh (int h_pixels, int v_lines, float freq, + int interlaced, int margins); +options *parse_command_line (int argc, char *argv[]); + + + + +/* + * print_value() - print the result of the named computation; this is + * useful when comparing against the GTF EXCEL spreadsheet. + */ + +int global_verbose = 0; + +void print_value(int n, char *name, float val) +{ + if (global_verbose) { + printf("%2d: %-27s: %15f\n", n, name, val); + } +} + + + +/* print_xf86_mode() - print the XFree86 modeline, given mode timings. */ + +void print_xf86_mode (mode *m) +{ + printf ("\n"); + printf (" # %dx%d @ %.2f Hz (GTF) hsync: %.2f kHz; pclk: %.2f MHz\n", + m->hr, m->vr, m->v_freq, m->h_freq, m->pclk); + + printf (" Modeline \"%dx%d_%.2f\" %.2f" + " %d %d %d %d" + " %d %d %d %d" + " -HSync +Vsync\n\n", + m->hr, m->vr, m->v_freq, m->pclk, + m->hr, m->hss, m->hse, m->hfl, + m->vr, m->vss, m->vse, m->vfl); + +} + + + +/* + * print_fb_mode() - print a mode description in fbset(8) format; + * see the fb.modes(8) manpage. The timing description used in + * this is rather odd; they use "left and right margin" to refer + * to the portion of the hblank before and after the sync pulse + * by conceptually wrapping the portion of the blank after the pulse + * to infront of the visible region; ie: + * + * + * Timing description I'm accustomed to: + * + * + * + * <--------1--------> <--2--> <--3--> <--4--> + * _________ + * |-------------------|_______| |_______ + * + * R SS SE FL + * + * 1: visible image + * 2: blank before sync (aka front porch) + * 3: sync pulse + * 4: blank after sync (aka back porch) + * R: Resolution + * SS: Sync Start + * SE: Sync End + * FL: Frame Length + * + * + * But the fb.modes format is: + * + * + * <--4--> <--------1--------> <--2--> <--3--> + * _________ + * _______|-------------------|_______| | + * + * The fb.modes(8) manpage refers to <4> and <2> as the left and + * right "margin" (as well as upper and lower margin in the vertical + * direction) -- note that this has nothing to do with the term + * "margin" used in the GTF Timing Standard. + * + * XXX always prints the 32 bit mode -- should I provide a command + * line option to specify the bpp? It's simple enough for a user + * to edit the mode description after it's generated. + */ + +void print_fb_mode (mode *m) +{ + printf ("\n"); + printf ("mode \"%dx%d %.2fHz 32bit (GTF)\"\n", + m->hr, m->vr, m->v_freq); + printf (" # PCLK: %.2f MHz, H: %.2f kHz, V: %.2f Hz\n", + m->pclk, m->h_freq, m->v_freq); + printf (" geometry %d %d %d %d 32\n", + m->hr, m->vr, m->hr, m->vr); + printf (" timings %d %d %d %d %d %d %d\n", + (int) rint(1000000.0/m->pclk),/* pixclock in picoseconds */ + m->hfl - m->hse, /* left margin (in pixels) */ + m->hss - m->hr, /* right margin (in pixels) */ + m->vfl - m->vse, /* upper margin (in pixel lines) */ + m->vss - m->vr, /* lower margin (in pixel lines) */ + m->hse - m->hss, /* horizontal sync length (pixels) */ + m->vse - m->vss); /* vert sync length (pixel lines) */ + printf (" hsync low\n"); + printf (" vsync high\n"); + printf ("endmode\n\n"); + +} + + + + +/* + * vert_refresh() - as defined by the GTF Timing Standard, compute the + * Stage 1 Parameters using the vertical refresh frequency. In other + * words: input a desired resolution and desired refresh rate, and + * output the GTF mode timings. + * + * XXX All the code is in place to compute interlaced modes, but I don't + * feel like testing it right now. + * + * XXX margin computations are implemented but not tested (nor used by + * XFree86 of fbset mode descriptions, from what I can tell). + */ + +mode *vert_refresh (int h_pixels, int v_lines, float freq, + int interlaced, int margins) +{ + float h_pixels_rnd; + float v_lines_rnd; + float v_field_rate_rqd; + float top_margin; + float bottom_margin; + float interlace; + float h_period_est; + float vsync_plus_bp; + float v_back_porch; + float total_v_lines; + float v_field_rate_est; + float h_period; + float v_field_rate; + float v_frame_rate; + float left_margin; + float right_margin; + float total_active_pixels; + float ideal_duty_cycle; + float h_blank; + float total_pixels; + float pixel_freq; + float h_freq; + + float h_sync; + float h_front_porch; + float v_odd_front_porch_lines; + + mode *m = (mode*) malloc (sizeof (mode)); + + + /* 1. In order to give correct results, the number of horizontal + * pixels requested is first processed to ensure that it is divisible + * by the character size, by rounding it to the nearest character + * cell boundary: + * + * [H PIXELS RND] = ((ROUND([H PIXELS]/[CELL GRAN RND],0))*[CELLGRAN RND]) + */ + + h_pixels_rnd = rint((float) h_pixels / CELL_GRAN) * CELL_GRAN; + + print_value(1, "[H PIXELS RND]", h_pixels_rnd); + + + /* 2. If interlace is requested, the number of vertical lines assumed + * by the calculation must be halved, as the computation calculates + * the number of vertical lines per field. In either case, the + * number of lines is rounded to the nearest integer. + * + * [V LINES RND] = IF([INT RQD?]="y", ROUND([V LINES]/2,0), + * ROUND([V LINES],0)) + */ + + v_lines_rnd = interlaced ? + rint((float) v_lines) / 2.0 : + rint((float) v_lines); + + print_value(2, "[V LINES RND]", v_lines_rnd); + + + /* 3. Find the frame rate required: + * + * [V FIELD RATE RQD] = IF([INT RQD?]="y", [I/P FREQ RQD]*2, + * [I/P FREQ RQD]) + */ + + v_field_rate_rqd = interlaced ? (freq * 2.0) : (freq); + + print_value(3, "[V FIELD RATE RQD]", v_field_rate_rqd); + + + /* 4. Find number of lines in Top margin: + * + * [TOP MARGIN (LINES)] = IF([MARGINS RQD?]="Y", + * ROUND(([MARGIN%]/100*[V LINES RND]),0), + * 0) + */ + + top_margin = margins ? rint(MARGIN_PERCENT / 100.0 * v_lines_rnd) : (0.0); + + print_value(4, "[TOP MARGIN (LINES)]", top_margin); + + + /* 5. Find number of lines in Bottom margin: + * + * [BOT MARGIN (LINES)] = IF([MARGINS RQD?]="Y", + * ROUND(([MARGIN%]/100*[V LINES RND]),0), + * 0) + */ + + bottom_margin = margins ? rint(MARGIN_PERCENT/100.0 * v_lines_rnd) : (0.0); + + print_value(5, "[BOT MARGIN (LINES)]", bottom_margin); + + + /* 6. If interlace is required, then set variable [INTERLACE]=0.5: + * + * [INTERLACE]=(IF([INT RQD?]="y",0.5,0)) + */ + + interlace = interlaced ? 0.5 : 0.0; + + print_value(6, "[INTERLACE]", interlace); + + + /* 7. Estimate the Horizontal period + * + * [H PERIOD EST] = ((1/[V FIELD RATE RQD]) - [MIN VSYNC+BP]/1000000) / + * ([V LINES RND] + (2*[TOP MARGIN (LINES)]) + + * [MIN PORCH RND]+[INTERLACE]) * 1000000 + */ + + h_period_est = (((1.0/v_field_rate_rqd) - (MIN_VSYNC_PLUS_BP/1000000.0)) + / (v_lines_rnd + (2*top_margin) + MIN_PORCH + interlace) + * 1000000.0); + + print_value(7, "[H PERIOD EST]", h_period_est); + + + /* 8. Find the number of lines in V sync + back porch: + * + * [V SYNC+BP] = ROUND(([MIN VSYNC+BP]/[H PERIOD EST]),0) + */ + + vsync_plus_bp = rint(MIN_VSYNC_PLUS_BP/h_period_est); + + print_value(8, "[V SYNC+BP]", vsync_plus_bp); + + + /* 9. Find the number of lines in V back porch alone: + * + * [V BACK PORCH] = [V SYNC+BP] - [V SYNC RND] + * + * XXX is "[V SYNC RND]" a typo? should be [V SYNC RQD]? + */ + + v_back_porch = vsync_plus_bp - V_SYNC_RQD; + + print_value(9, "[V BACK PORCH]", v_back_porch); + + + /* 10. Find the total number of lines in Vertical field period: + * + * [TOTAL V LINES] = [V LINES RND] + [TOP MARGIN (LINES)] + + * [BOT MARGIN (LINES)] + [V SYNC+BP] + [INTERLACE] + + * [MIN PORCH RND] + */ + + total_v_lines = v_lines_rnd + top_margin + bottom_margin + vsync_plus_bp + + interlace + MIN_PORCH; + + print_value(10, "[TOTAL V LINES]", total_v_lines); + + + /* 11. Estimate the Vertical field frequency: + * + * [V FIELD RATE EST] = 1 / [H PERIOD EST] / [TOTAL V LINES] * 1000000 + */ + + v_field_rate_est = 1.0 / h_period_est / total_v_lines * 1000000.0; + + print_value(11, "[V FIELD RATE EST]", v_field_rate_est); + + + /* 12. Find the actual horizontal period: + * + * [H PERIOD] = [H PERIOD EST] / ([V FIELD RATE RQD] / [V FIELD RATE EST]) + */ + + h_period = h_period_est / (v_field_rate_rqd / v_field_rate_est); + + print_value(12, "[H PERIOD]", h_period); + + + /* 13. Find the actual Vertical field frequency: + * + * [V FIELD RATE] = 1 / [H PERIOD] / [TOTAL V LINES] * 1000000 + */ + + v_field_rate = 1.0 / h_period / total_v_lines * 1000000.0; + + print_value(13, "[V FIELD RATE]", v_field_rate); + + + /* 14. Find the Vertical frame frequency: + * + * [V FRAME RATE] = (IF([INT RQD?]="y", [V FIELD RATE]/2, [V FIELD RATE])) + */ + + v_frame_rate = interlaced ? v_field_rate / 2.0 : v_field_rate; + + print_value(14, "[V FRAME RATE]", v_frame_rate); + + + /* 15. Find number of pixels in left margin: + * + * [LEFT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y", + * (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 / + * [CELL GRAN RND]),0)) * [CELL GRAN RND], + * 0)) + */ + + left_margin = margins ? + rint(h_pixels_rnd * MARGIN_PERCENT / 100.0 / CELL_GRAN) * CELL_GRAN : + 0.0; + + print_value(15, "[LEFT MARGIN (PIXELS)]", left_margin); + + + /* 16. Find number of pixels in right margin: + * + * [RIGHT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y", + * (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 / + * [CELL GRAN RND]),0)) * [CELL GRAN RND], + * 0)) + */ + + right_margin = margins ? + rint(h_pixels_rnd * MARGIN_PERCENT / 100.0 / CELL_GRAN) * CELL_GRAN : + 0.0; + + print_value(16, "[RIGHT MARGIN (PIXELS)]", right_margin); + + + /* 17. Find total number of active pixels in image and left and right + * margins: + * + * [TOTAL ACTIVE PIXELS] = [H PIXELS RND] + [LEFT MARGIN (PIXELS)] + + * [RIGHT MARGIN (PIXELS)] + */ + + total_active_pixels = h_pixels_rnd + left_margin + right_margin; + + print_value(17, "[TOTAL ACTIVE PIXELS]", total_active_pixels); + + + /* 18. Find the ideal blanking duty cycle from the blanking duty cycle + * equation: + * + * [IDEAL DUTY CYCLE] = [C'] - ([M']*[H PERIOD]/1000) + */ + + ideal_duty_cycle = C_PRIME - (M_PRIME * h_period / 1000.0); + + print_value(18, "[IDEAL DUTY CYCLE]", ideal_duty_cycle); + + + /* 19. Find the number of pixels in the blanking time to the nearest + * double character cell: + * + * [H BLANK (PIXELS)] = (ROUND(([TOTAL ACTIVE PIXELS] * + * [IDEAL DUTY CYCLE] / + * (100-[IDEAL DUTY CYCLE]) / + * (2*[CELL GRAN RND])), 0)) + * * (2*[CELL GRAN RND]) + */ + + h_blank = rint(total_active_pixels * + ideal_duty_cycle / + (100.0 - ideal_duty_cycle) / + (2.0 * CELL_GRAN)) * (2.0 * CELL_GRAN); + + print_value(19, "[H BLANK (PIXELS)]", h_blank); + + + /* 20. Find total number of pixels: + * + * [TOTAL PIXELS] = [TOTAL ACTIVE PIXELS] + [H BLANK (PIXELS)] + */ + + total_pixels = total_active_pixels + h_blank; + + print_value(20, "[TOTAL PIXELS]", total_pixels); + + + /* 21. Find pixel clock frequency: + * + * [PIXEL FREQ] = [TOTAL PIXELS] / [H PERIOD] + */ + + pixel_freq = total_pixels / h_period; + + print_value(21, "[PIXEL FREQ]", pixel_freq); + + + /* 22. Find horizontal frequency: + * + * [H FREQ] = 1000 / [H PERIOD] + */ + + h_freq = 1000.0 / h_period; + + print_value(22, "[H FREQ]", h_freq); + + + + /* Stage 1 computations are now complete; I should really pass + the results to another function and do the Stage 2 + computations, but I only need a few more values so I'll just + append the computations here for now */ + + + + /* 17. Find the number of pixels in the horizontal sync period: + * + * [H SYNC (PIXELS)] =(ROUND(([H SYNC%] / 100 * [TOTAL PIXELS] / + * [CELL GRAN RND]),0))*[CELL GRAN RND] + */ + + h_sync = rint(H_SYNC_PERCENT/100.0 * total_pixels / CELL_GRAN) * CELL_GRAN; + + print_value(17, "[H SYNC (PIXELS)]", h_sync); + + + /* 18. Find the number of pixels in the horizontal front porch period: + * + * [H FRONT PORCH (PIXELS)] = ([H BLANK (PIXELS)]/2)-[H SYNC (PIXELS)] + */ + + h_front_porch = (h_blank / 2.0) - h_sync; + + print_value(18, "[H FRONT PORCH (PIXELS)]", h_front_porch); + + + /* 36. Find the number of lines in the odd front porch period: + * + * [V ODD FRONT PORCH(LINES)]=([MIN PORCH RND]+[INTERLACE]) + */ + + v_odd_front_porch_lines = MIN_PORCH + interlace; + + print_value(36, "[V ODD FRONT PORCH(LINES)]", v_odd_front_porch_lines); + + + /* finally, pack the results in the mode struct */ + + m->hr = (int) (h_pixels_rnd); + m->hss = (int) (h_pixels_rnd + h_front_porch); + m->hse = (int) (h_pixels_rnd + h_front_porch + h_sync); + m->hfl = (int) (total_pixels); + + m->vr = (int) (v_lines_rnd); + m->vss = (int) (v_lines_rnd + v_odd_front_porch_lines); + m->vse = (int) (int) (v_lines_rnd + v_odd_front_porch_lines + V_SYNC_RQD); + m->vfl = (int) (total_v_lines); + + m->pclk = pixel_freq; + m->h_freq = h_freq; + m->v_freq = freq; + + return (m); + +} + + + + +/* + * parse_command_line() - parse the command line and return an + * alloced structure containing the results. On error print usage + * and return NULL. + */ + +options *parse_command_line (int argc, char *argv[]) +{ + int n; + + options *o = (options *) calloc (1, sizeof (options)); + + if (argc < 4) goto bad_option; + + o->x = atoi (argv[1]); + o->y = atoi (argv[2]); + o->v_freq = atof (argv[3]); + + /* XXX should check for errors in the above */ + + n = 4; + + while (n < argc) { + if ((strcmp (argv[n], "-v") == 0) || + (strcmp (argv[n], "--verbose") == 0)) { + global_verbose = 1; + } else if ((strcmp (argv[n], "-f") == 0) || + (strcmp (argv[n], "--fbmode") == 0)) { + o->fbmode = 1; + } else if ((strcmp (argv[n], "-x") == 0) || + (strcmp (argv[n], "--xf86mode") == 0)) { + o->xf86mode = 1; + } else { + goto bad_option; + } + + n++; + } + + /* if neither xf86mode nor fbmode were requested, default to + xf86mode */ + + if (!o->fbmode && !o->xf86mode) o->xf86mode = 1; + + return (o); + + bad_option: + + fprintf (stderr, "\n"); + fprintf (stderr, "usage: %s x y refresh [-v|--verbose] " + "[-f|--fbmode] [-x|-xf86mode]\n", argv[0]); + + fprintf (stderr, "\n"); + + fprintf (stderr, " x : the desired horizontal " + "resolution (required)\n"); + fprintf (stderr, " y : the desired vertical " + "resolution (required)\n"); + fprintf (stderr, " refresh : the desired refresh " + "rate (required)\n"); + fprintf (stderr, " -v|--verbose : enable verbose printouts " + "(traces each step of the computation)\n"); + fprintf (stderr, " -f|--fbmode : output an fbset(8)-style mode " + "description\n"); + fprintf (stderr, " -x|-xf86mode : output an XFree86-style mode " + "description (this is the default\n" + " if no mode description is requested)\n"); + + fprintf (stderr, "\n"); + + free (o); + return (NULL); + +} + + + +int main (int argc, char *argv[]) +{ + mode *m; + options *o; + + o = parse_command_line (argc, argv); + if (!o) exit (1); + + m = vert_refresh (o->x, o->y, o->v_freq, 0, 0); + if (!m) exit (1); + + if (o->xf86mode) + print_xf86_mode(m); + + if (o->fbmode) + print_fb_mode(m); + + return 0; + +} |