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-rw-r--r--xorg-server/hw/xfree86/utils/gtf/gtf.c1482
1 files changed, 741 insertions, 741 deletions
diff --git a/xorg-server/hw/xfree86/utils/gtf/gtf.c b/xorg-server/hw/xfree86/utils/gtf/gtf.c
index 840626c66..87fcb3f0e 100644
--- a/xorg-server/hw/xfree86/utils/gtf/gtf.c
+++ b/xorg-server/hw/xfree86/utils/gtf/gtf.c
@@ -1,741 +1,741 @@
-/* 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 XServer 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 XServer 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.
- *
- */
-
-#ifdef HAVE_XORG_CONFIG_H
-# include <xorg-config.h>
-#endif
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-
-#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 xorgmode, 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 XServer 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
- * XServer 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], "--xorgmode") == 0) ||
- (strcmp (argv[n], "--xf86mode") == 0)) {
- o->xorgmode = 1;
- } else {
- goto bad_option;
- }
-
- n++;
- }
-
- /* if neither xorgmode nor fbmode were requested, default to
- xorgmode */
-
- if (!o->fbmode && !o->xorgmode) o->xorgmode = 1;
-
- return o;
-
- bad_option:
-
- fprintf (stderr, "\n");
- fprintf (stderr, "usage: %s x y refresh [-v|--verbose] "
- "[-f|--fbmode] [-x|--xorgmode]\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|--xorgmode : output an "__XSERVERNAME__"-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->xorgmode)
- print_xf86_mode(m);
-
- if (o->fbmode)
- print_fb_mode(m);
-
- return 0;
-
-}
+/* 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 XServer 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 XServer 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.
+ *
+ */
+
+#ifdef HAVE_XORG_CONFIG_H
+# include <xorg-config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#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 xorgmode, fbmode;
+ float v_freq;
+} options;
+
+
+
+
+/* prototypes */
+
+void print_value(int n, const 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, const char *name, float val)
+{
+ if (global_verbose) {
+ printf("%2d: %-27s: %15f\n", n, name, val);
+ }
+}
+
+
+
+/* print_xf86_mode() - print the XServer 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
+ * XServer 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], "--xorgmode") == 0) ||
+ (strcmp (argv[n], "--xf86mode") == 0)) {
+ o->xorgmode = 1;
+ } else {
+ goto bad_option;
+ }
+
+ n++;
+ }
+
+ /* if neither xorgmode nor fbmode were requested, default to
+ xorgmode */
+
+ if (!o->fbmode && !o->xorgmode) o->xorgmode = 1;
+
+ return o;
+
+ bad_option:
+
+ fprintf (stderr, "\n");
+ fprintf (stderr, "usage: %s x y refresh [-v|--verbose] "
+ "[-f|--fbmode] [-x|--xorgmode]\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|--xorgmode : output an "__XSERVERNAME__"-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->xorgmode)
+ print_xf86_mode(m);
+
+ if (o->fbmode)
+ print_fb_mode(m);
+
+ return 0;
+
+}