sys/dev/videomode/vesagtf.h

root/sys/dev/videomode/vesagtf.h
/*      $NetBSD$        */

/*-
 * 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.
 */ 

#ifndef _DEV_VIDEOMODE_VESAGTF_H
#define _DEV_VIDEOMODE_VESAGTF_H

/*
 * Use VESA GTF formula to generate a monitor mode, given resolution and
 * refresh rates.
 */

struct vesagtf_params {
        unsigned        margin_ppt;     /* vertical margin size, percent * 10
                                         * think parts-per-thousand */
        unsigned        min_porch;      /* minimum front porch */
        unsigned        vsync_rqd;      /* width of vsync in lines */
        unsigned        hsync_pct;      /* hsync as % of total width */
        unsigned        min_vsbp;       /* minimum vsync + back porch (usec) */
        unsigned        M;              /* blanking formula gradient */
        unsigned        C;              /* blanking formula offset */
        unsigned        K;              /* blanking formula scaling factor */
        unsigned        J;              /* blanking formula scaling factor */
};

/*
 * Default values to use for params.
 */
#define VESAGTF_MARGIN_PPT      18      /* 1.8% */
#define VESAGTF_MIN_PORCH       1       /* minimum front porch */
#define VESAGTF_VSYNC_RQD       3       /* vsync width in lines */
#define VESAGTF_HSYNC_PCT       8       /* width of hsync % of total line */
#define VESAGTF_MIN_VSBP        550     /* min vsync + back porch (usec) */
#define VESAGTF_M               600     /* blanking formula gradient */
#define VESAGTF_C               40      /* blanking formula offset */
#define VESAGTF_K               128     /* blanking formula scaling factor */
#define VESAGTF_J               20      /* blanking formula scaling factor */

/*
 * Use VESA GTF formula to generate monitor timings.  Assumes default
 * GTF parameters, non-interlaced, and no margins.
 */
void vesagtf_mode(unsigned x, unsigned y, unsigned refresh,
    struct videomode *);

/*
 * A more complete version, in case we ever want to use alternate GTF
 * parameters.  EDID 1.3 allows for "secondary GTF parameters".
 */
void vesagtf_mode_params(unsigned x, unsigned y, unsigned refresh,
    struct vesagtf_params *, int flags, struct videomode *);

#define VESAGTF_FLAG_ILACE      0x0001          /* use interlace */
#define VESAGTF_FLAG_MARGINS    0x0002          /* use margins */

#endif /* _DEV_VIDEOMODE_VESAGTF_H */
FreeBSD
