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vesagtf.h revision 1.1 
      1 /*	$NetBSD: vesagtf.h,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 #ifndef _DEV_VIDEOMODE_VESAGTF_H
     35 #define _DEV_VIDEOMODE_VESAGTF_H
     36 
     37 /*
     38  * Use VESA GTF formula to generate a monitor mode, given resolution and
     39  * refresh rates.
     40  */
     41 
     42 struct vesagtf_params {
     43 	unsigned	margin_ppt;	/* vertical margin size, percent * 10
     44 					 * think parts-per-thousand */
     45 	unsigned	min_porch;	/* minimum front porch */
     46 	unsigned	vsync_rqd;	/* width of vsync in lines */
     47 	unsigned	hsync_pct;	/* hsync as % of total width */
     48 	unsigned	min_vsbp;	/* minimum vsync + back porch (usec) */
     49 	unsigned	M;		/* blanking formula gradient */
     50 	unsigned	C;		/* blanking formula offset */
     51 	unsigned	K;		/* blanking formula scaling factor */
     52 	unsigned	J;		/* blanking formula scaling factor */
     53 };
     54 
     55 /*
     56  * Default values to use for params.
     57  */
     58 #define	VESAGTF_MARGIN_PPT	18	/* 1.8% */
     59 #define	VESAGTF_MIN_PORCH	1	/* minimum front porch */
     60 #define	VESAGTF_VSYNC_RQD	3	/* vsync width in lines */
     61 #define	VESAGTF_HSYNC_PCT	8	/* width of hsync % of total line */
     62 #define	VESAGTF_MIN_VSBP	550	/* min vsync + back porch (usec) */
     63 #define	VESAGTF_M		600	/* blanking formula gradient */
     64 #define	VESAGTF_C		40	/* blanking formula offset */
     65 #define	VESAGTF_K		128	/* blanking formula scaling factor */
     66 #define	VESAGTF_J		20	/* blanking formula scaling factor */
     67 
     68 /*
     69  * Use VESA GTF formula to generate monitor timings.  Assumes default
     70  * GTF parameters, non-interlaced, and no margins.
     71  */
     72 void vesagtf_mode(unsigned x, unsigned y, unsigned refresh,
     73     struct videomode *);
     74 
     75 /*
     76  * A more complete version, in case we ever want to use alternate GTF
     77  * parameters.  EDID 1.3 allows for "secondary GTF parameters".
     78  */
     79 void vesagtf_mode_params(unsigned x, unsigned y, unsigned refresh,
     80     struct vesagtf_params *, int flags, struct videomode *);
     81 
     82 #define	VESAGTF_FLAG_ILACE	0x0001		/* use interlace */
     83 #define	VESAGTF_FLAG_MARGINS	0x0002		/* use margins */
     84 
     85 #endif /* _DEV_VIDEOMODE_VESAGTF_H */
     86