1/*	$NetBSD: btvar.h,v 1.1.68.4 2005/01/24 08:34:47 skrll Exp $ */
2
3/*
4 * Copyright (c) 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
10 *
11 * All advertising materials mentioning features or use of this software
12 * must display the following acknowledgement:
13 *	This product includes software developed by the University of
14 *	California, Lawrence Berkeley Laboratory.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 *    notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 *    notice, this list of conditions and the following disclaimer in the
23 *    documentation and/or other materials provided with the distribution.
24 * 3. Neither the name of the University nor the names of its contributors
25 *    may be used to endorse or promote products derived from this software
26 *    without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 *	@(#)btvar.h	8.2 (Berkeley) 1/21/94
41 */
42
43/*
44 * Brooktree color frame buffer state variables (see btreg.h).
45 *
46 * Unfortunately, remarkably little code can be shared between the
47 * cg3 and cg6 drivers here, as the cg3 registers do longword-ops
48 * `as expected', but the cg6 ones use only the upper byte.
49 *
50 * Still, the software color map manipulation is not completely trivial.
51 */
52union bt_cmap {
53	u_char  cm_map[256][3];		/* 256 R/G/B entries */
54	u_int   cm_chip[256 * 3 / 4];	/* the way the chip gets loaded */
55};
56
57/*
58 * Routines in bt_subr.c.
59 */
60int	bt_getcmap(struct fbcmap *, union bt_cmap *, int);
61int	bt_putcmap(struct fbcmap *, union bt_cmap *, int);
62
63/*
64 * Compute (x / 4) * 3 and (x / 4) * 4.  These are used in turning
65 * RGB indices (which are in multiples of three) into `chip RGB' values
66 * (which are in multiples of four).
67 */
68#define	BT_D4M3(x) ((((x) >> 2) << 1) + ((x) >> 2))	/* (x / 4) * 3 */
69#define	BT_D4M4(x) ((x) & ~3)				/* (x / 4) * 4 */
70