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+#include <machine/rtems-bsd-kernel-space.h>
+
+/* $NetBSD: vesagtf.c,v 1.2 2013/09/15 15:56:07 martin Exp $ */
+/* $FreeBSD$ */
+
+/*-
+ * Copyright (c) 2006 Itronix Inc.
+ * All rights reserved.
+ *
+ * Written by Garrett D'Amore for Itronix Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. The name of Itronix Inc. may not be used to endorse
+ * or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``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 ITRONIX INC. 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 was derived from a userland GTF program supplied by NVIDIA.
+ * NVIDIA's original boilerplate follows.
+ *
+ * Note that I have heavily modified the program for use in the EDID
+ * kernel code for NetBSD, including removing the use of floating
+ * point operations and making significant adjustments to minimize
+ * error propagation while operating with integer only math.
+ *
+ * This has required the use of 64-bit integers in a few places, but
+ * the upshot is that for a calculation of 1920x1200x85 (as an
+ * example), the error deviates by only ~.004% relative to the
+ * floating point version. This error is *well* within VESA
+ * tolerances.
+ */
+
+/*
+ * 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.
+ *
+ */
+
+
+#ifdef _KERNEL
+#include <sys/cdefs.h>
+
+__FBSDID("$FreeBSD$");
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <dev/videomode/videomode.h>
+#include <dev/videomode/vesagtf.h>
+#else
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include "videomode.h"
+#include "vesagtf.h"
+
+void print_xf86_mode(struct videomode *m);
+#endif
+
+#define CELL_GRAN 8 /* assumed character cell granularity */
+
+/* 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)
+ */
+
+/*
+ * C' and M' multiplied by 256 to give integer math. Make sure to
+ * scale results using these back down, appropriately.
+ */
+#define C_PRIME256(p) (((p->C - p->J) * p->K) + (p->J * 256))
+#define M_PRIME256(p) (p->K * p->M)
+
+#define DIVIDE(x,y) (((x) + ((y) / 2)) / (y))
+
+/*
+ * print_value() - print the result of the named computation; this is
+ * useful when comparing against the GTF EXCEL spreadsheet.
+ */
+
+#ifdef GTFDEBUG
+
+static void
+print_value(int n, const char *name, unsigned val)
+{
+ printf("%2d: %-27s: %u\n", n, name, val);
+}
+#else
+#define print_value(n, name, val)
+#endif
+
+
+/*
+ * 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).
+ */
+
+void
+vesagtf_mode_params(unsigned h_pixels, unsigned v_lines, unsigned freq,
+ struct vesagtf_params *params, int flags, struct videomode *vmp)
+{
+ unsigned v_field_rqd;
+ unsigned top_margin;
+ unsigned bottom_margin;
+ unsigned interlace;
+ uint64_t h_period_est;
+ unsigned vsync_plus_bp;
+ unsigned v_back_porch __unused;
+ unsigned total_v_lines;
+ uint64_t v_field_est;
+ uint64_t h_period;
+ unsigned v_field_rate;
+ unsigned v_frame_rate __unused;
+ unsigned left_margin;
+ unsigned right_margin;
+ unsigned total_active_pixels;
+ uint64_t ideal_duty_cycle;
+ unsigned h_blank;
+ unsigned total_pixels;
+ unsigned pixel_freq;
+
+ unsigned h_sync;
+ unsigned h_front_porch;
+ unsigned v_odd_front_porch_lines;
+
+#ifdef GTFDEBUG
+ unsigned h_freq;
+#endif
+
+ /* 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 = DIVIDE(h_pixels, CELL_GRAN) * CELL_GRAN;
+
+ print_value(1, "[H PIXELS RND]", h_pixels);
+
+
+ /* 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 = (flags & VESAGTF_FLAG_ILACE) ? DIVIDE(v_lines, 2) : v_lines;
+
+ print_value(2, "[V LINES RND]", v_lines);
+
+
+ /* 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_rqd = (flags & VESAGTF_FLAG_ILACE) ? (freq * 2) : (freq);
+
+ print_value(3, "[V FIELD RATE RQD]", v_field_rqd);
+
+
+ /* 4. Find number of lines in Top margin:
+ * 5. Find number of lines in Bottom margin:
+ *
+ * [TOP MARGIN (LINES)] = IF([MARGINS RQD?]="Y",
+ * ROUND(([MARGIN%]/100*[V LINES RND]),0),
+ * 0)
+ *
+ * Ditto for bottom margin. Note that instead of %, we use PPT, which
+ * is parts per thousand. This helps us with integer math.
+ */
+
+ top_margin = bottom_margin = (flags & VESAGTF_FLAG_MARGINS) ?
+ DIVIDE(v_lines * params->margin_ppt, 1000) : 0;
+
+ print_value(4, "[TOP MARGIN (LINES)]", top_margin);
+ 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))
+ *
+ * To make this integer friendly, we use some special hacks in step
+ * 7 below. Please read those comments to understand why I am using
+ * a whole number of 1.0 instead of 0.5 here.
+ */
+ interlace = (flags & VESAGTF_FLAG_ILACE) ? 1 : 0;
+
+ print_value(6, "[2*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
+ *
+ * To make it integer friendly, we pre-multiply the 1000000 to get to
+ * usec. This gives us:
+ *
+ * [H PERIOD EST] = ((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP]) /
+ * ([V LINES RND] + (2 * [TOP MARGIN (LINES)]) +
+ * [MIN PORCH RND]+[INTERLACE])
+ *
+ * The other problem is that the interlace value is wrong. To get
+ * the interlace to a whole number, we multiply both the numerator and
+ * divisor by 2, so we can use a value of either 1 or 0 for the interlace
+ * factor.
+ *
+ * This gives us:
+ *
+ * [H PERIOD EST] = ((2*((1000000/[V FIELD RATE RQD]) - [MIN VSYNC+BP])) /
+ * (2*([V LINES RND] + (2*[TOP MARGIN (LINES)]) +
+ * [MIN PORCH RND]) + [2*INTERLACE]))
+ *
+ * Finally we multiply by another 1000, to get value in picosec.
+ * Why picosec? To minimize rounding errors. Gotta love integer
+ * math and error propagation.
+ */
+
+ h_period_est = DIVIDE(((DIVIDE(2000000000000ULL, v_field_rqd)) -
+ (2000000 * params->min_vsbp)),
+ ((2 * (v_lines + (2 * top_margin) + params->min_porch)) + interlace));
+
+ print_value(7, "[H PERIOD EST (ps)]", 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)
+ *
+ * But recall that h_period_est is in psec. So multiply by 1000000.
+ */
+
+ vsync_plus_bp = DIVIDE(params->min_vsbp * 1000000, 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 - params->vsync_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 + top_margin + bottom_margin + vsync_plus_bp +
+ interlace + params->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
+ *
+ * Again, we want to pre multiply by 10^9 to convert for nsec, thereby
+ * making it usable in integer math.
+ *
+ * So we get:
+ *
+ * [V FIELD RATE EST] = 1000000000 / [H PERIOD EST] / [TOTAL V LINES]
+ *
+ * This is all scaled to get the result in uHz. Again, we're trying to
+ * minimize error propagation.
+ */
+ v_field_est = DIVIDE(DIVIDE(1000000000000000ULL, h_period_est),
+ total_v_lines);
+
+ print_value(11, "[V FIELD RATE EST(uHz)]", v_field_est);
+
+
+ /* 12. Find the actual horizontal period:
+ *
+ * [H PERIOD] = [H PERIOD EST] / ([V FIELD RATE RQD] / [V FIELD RATE EST])
+ */
+
+ h_period = DIVIDE(h_period_est * v_field_est, v_field_rqd * 1000);
+
+ print_value(12, "[H PERIOD(ps)]", h_period);
+
+
+ /* 13. Find the actual Vertical field frequency:
+ *
+ * [V FIELD RATE] = 1 / [H PERIOD] / [TOTAL V LINES] * 1000000
+ *
+ * And again, we convert to nsec ahead of time, giving us:
+ *
+ * [V FIELD RATE] = 1000000 / [H PERIOD] / [TOTAL V LINES]
+ *
+ * And another rescaling back to mHz. Gotta love it.
+ */
+
+ v_field_rate = DIVIDE(1000000000000ULL, h_period * total_v_lines);
+
+ 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]))
+ *
+ * N.B. that the result here is in mHz.
+ */
+
+ v_frame_rate = (flags & VESAGTF_FLAG_ILACE) ?
+ v_field_rate / 2 : v_field_rate;
+
+ print_value(14, "[V FRAME RATE]", v_frame_rate);
+
+
+ /* 15. Find number of pixels in left margin:
+ * 16. Find number of pixels in right margin:
+ *
+ * [LEFT MARGIN (PIXELS)] = (IF( [MARGINS RQD?]="Y",
+ * (ROUND( ([H PIXELS RND] * [MARGIN%] / 100 /
+ * [CELL GRAN RND]),0)) * [CELL GRAN RND],
+ * 0))
+ *
+ * Again, we deal with margin percentages as PPT (parts per thousand).
+ * And the calculations for left and right are the same.
+ */
+
+ left_margin = right_margin = (flags & VESAGTF_FLAG_MARGINS) ?
+ DIVIDE(DIVIDE(h_pixels * params->margin_ppt, 1000),
+ CELL_GRAN) * CELL_GRAN : 0;
+
+ print_value(15, "[LEFT MARGIN (PIXELS)]", left_margin);
+ 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 + 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)
+ *
+ * However, we have modified values for [C'] as [256*C'] and
+ * [M'] as [256*M']. Again the idea here is to get good scaling.
+ * We use 256 as the factor to make the math fast.
+ *
+ * Note that this means that we have to scale it appropriately in
+ * later calculations.
+ *
+ * The ending result is that our ideal_duty_cycle is 256000x larger
+ * than the duty cycle used by VESA. But again, this reduces error
+ * propagation.
+ */
+
+ ideal_duty_cycle =
+ ((C_PRIME256(params) * 1000) -
+ (M_PRIME256(params) * h_period / 1000000));
+
+ 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])
+ *
+ * Of course, we adjust to make this rounding work in integer math.
+ */
+
+ h_blank = DIVIDE(DIVIDE(total_active_pixels * ideal_duty_cycle,
+ (256000 * 100ULL) - ideal_duty_cycle),
+ 2 * CELL_GRAN) * (2 * 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]
+ *
+ * We calculate this in Hz rather than MHz, to get a value that
+ * is usable with integer math. Recall that the [H PERIOD] is in
+ * nsec.
+ */
+
+ pixel_freq = DIVIDE(total_pixels * 1000000, DIVIDE(h_period, 1000));
+
+ print_value(21, "[PIXEL FREQ]", pixel_freq);
+
+
+ /* 22. Find horizontal frequency:
+ *
+ * [H FREQ] = 1000 / [H PERIOD]
+ *
+ * I've ifdef'd this out, because we don't need it for any of
+ * our calculations.
+ * We calculate this in Hz rather than kHz, to avoid rounding
+ * errors. Recall that the [H PERIOD] is in usec.
+ */
+
+#ifdef GTFDEBUG
+ h_freq = 1000000000 / h_period;
+
+ print_value(22, "[H FREQ]", h_freq);
+#endif
+
+
+
+ /* 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]
+ *
+ * Rewriting for integer math:
+ *
+ * [H SYNC (PIXELS)]=(ROUND((H SYNC%] * [TOTAL PIXELS] / 100 /
+ * [CELL GRAN RND),0))*[CELL GRAN RND]
+ */
+
+ h_sync = DIVIDE(((params->hsync_pct * total_pixels) / 100), 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)]
+ *
+ * Note that h_blank is always an even number of characters (i.e.
+ * h_blank % (CELL_GRAN * 2) == 0)
+ */
+
+ h_front_porch = (h_blank / 2) - 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])
+ *
+ * Adjusting for the fact that the interlace is scaled:
+ *
+ * [V ODD FRONT PORCH(LINES)]=(([MIN PORCH RND] * 2) + [2*INTERLACE]) / 2
+ */
+
+ v_odd_front_porch_lines = ((2 * params->min_porch) + interlace) / 2;
+
+ print_value(36, "[V ODD FRONT PORCH(LINES)]", v_odd_front_porch_lines);
+
+
+ /* finally, pack the results in the mode struct */
+
+ vmp->hsync_start = h_pixels + h_front_porch;
+ vmp->hsync_end = vmp->hsync_start + h_sync;
+ vmp->htotal = total_pixels;
+ vmp->hdisplay = h_pixels;
+
+ vmp->vsync_start = v_lines + v_odd_front_porch_lines;
+ vmp->vsync_end = vmp->vsync_start + params->vsync_rqd;
+ vmp->vtotal = total_v_lines;
+ vmp->vdisplay = v_lines;
+
+ vmp->dot_clock = pixel_freq;
+
+}
+
+void
+vesagtf_mode(unsigned x, unsigned y, unsigned refresh, struct videomode *vmp)
+{
+ struct vesagtf_params params;
+
+ params.margin_ppt = VESAGTF_MARGIN_PPT;
+ params.min_porch = VESAGTF_MIN_PORCH;
+ params.vsync_rqd = VESAGTF_VSYNC_RQD;
+ params.hsync_pct = VESAGTF_HSYNC_PCT;
+ params.min_vsbp = VESAGTF_MIN_VSBP;
+ params.M = VESAGTF_M;
+ params.C = VESAGTF_C;
+ params.K = VESAGTF_K;
+ params.J = VESAGTF_J;
+
+ vesagtf_mode_params(x, y, refresh, &params, 0, vmp);
+}
+
+/*
+ * The tidbit here is so that you can compile this file as a
+ * standalone user program to generate X11 modelines using VESA GTF.
+ * This also allows for testing of the code itself, without
+ * necessitating a full kernel recompile.
+ */
+
+/* print_xf86_mode() - print the XFree86 modeline, given mode timings. */
+
+#ifndef _KERNEL
+void
+print_xf86_mode (struct videomode *vmp)
+{
+ float vf, hf;
+
+ hf = 1000.0 * vmp->dot_clock / vmp->htotal;
+ vf = 1.0 * hf / vmp->vtotal;
+
+ printf("\n");
+ printf(" # %dx%d @ %.2f Hz (GTF) hsync: %.2f kHz; pclk: %.2f MHz\n",
+ vmp->hdisplay, vmp->vdisplay, vf, hf, vmp->dot_clock / 1000.0);
+
+ printf(" Modeline \"%dx%d_%.2f\" %.2f"
+ " %d %d %d %d"
+ " %d %d %d %d"
+ " -HSync +Vsync\n\n",
+ vmp->hdisplay, vmp->vdisplay, vf, (vmp->dot_clock / 1000.0),
+ vmp->hdisplay, vmp->hsync_start, vmp->hsync_end, vmp->htotal,
+ vmp->vdisplay, vmp->vsync_start, vmp->vsync_end, vmp->vtotal);
+}
+
+int
+main (int argc, char *argv[])
+{
+ struct videomode m;
+
+ if (argc != 4) {
+ printf("usage: %s x y refresh\n", argv[0]);
+ exit(1);
+ }
+
+ vesagtf_mode(atoi(argv[1]), atoi(argv[2]), atoi(argv[3]), &m);
+
+ print_xf86_mode(&m);
+
+ return 0;
+
+}
+#endif