xref: /openbsd/sys/arch/amd64/isa/nvram.h (revision 76d0caae)
1 /*	$OpenBSD: nvram.h,v 1.1 2007/08/02 16:40:27 deraadt Exp $	*/
2 /*	$NetBSD: nvram.h,v 1.5 1995/05/05 22:08:43 mycroft Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * William Jolitz.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)rtc.h	8.1 (Berkeley) 6/11/93
36  */
37 
38 /*
39  * The following information is found in the non-volatile RAM in the
40  * MC146818A (or DS1287A or other compatible) RTC on AT-compatible PCs.
41  */
42 
43 /* NVRAM byte 0: bios diagnostic */
44 #define NVRAM_DIAG	(MC_NVRAM_START + 0)	/* RTC offset 0xe */
45 
46 #define NVRAM_DIAG_BITS		"\020\010clock_battery\007ROM_cksum\006config_unit\005memory_size\004fixed_disk\003invalid_time"
47 
48 /* NVRAM byte 1: reset code */
49 #define NVRAM_RESET	(MC_NVRAM_START + 1)	/* RTC offset 0xf */
50 
51 #define	NVRAM_RESET_RST		0x00		/* normal reset */
52 #define	NVRAM_RESET_LOAD 	0x04		/* load system */
53 #define	NVRAM_RESET_JUMP	0x0a		/* jump through 40:67 */
54 
55 /* NVRAM byte 2: diskette drive type in upper/lower nibble */
56 #define NVRAM_DISKETTE	(MC_NVRAM_START + 2)	/* RTC offset 0x10 */
57 
58 #define	NVRAM_DISKETTE_NONE	 0		/* none present */
59 #define	NVRAM_DISKETTE_360K	 0x10		/* 360K */
60 #define	NVRAM_DISKETTE_12M	 0x20		/* 1.2M */
61 #define	NVRAM_DISKETTE_720K	 0x30		/* 720K */
62 #define	NVRAM_DISKETTE_144M	 0x40		/* 1.44M */
63 #define	NVRAM_DISKETTE_TYPE5	 0x50		/* 2.88M, presumably */
64 #define	NVRAM_DISKETTE_TYPE6	 0x60		/* 2.88M */
65 
66 /* NVRAM byte 6: equipment type */
67 #define	NVRAM_EQUIPMENT	(MC_NVRAM_START + 6)
68 
69 #define	NVRAM_EQUIPMENT_FLOPPY	0x01		/* floppy installed */
70 #define	NVRAM_EQUIPMENT_FPU	0x02		/* FPU installed */
71 #define	NVRAM_EQUIPMENT_KBD	0x04		/* keyboard installed */
72 #define	NVRAM_EQUIPMENT_DISPLAY	0x08		/* display installed */
73 #define	NVRAM_EQUIPMENT_EGAVGA	0x00		/* EGA or VGA */
74 #define	NVRAM_EQUIPMENT_COLOR40	0x10		/* 40 column color */
75 #define	NVRAM_EQUIPMENT_COLOR80	0x20		/* 80 column color */
76 #define	NVRAM_EQUIPMENT_MONO80	0x30		/* 80 column mono */
77 #define	NVRAM_EQUIPMENT_MONITOR	0x30		/* mask for monitor type */
78 #define	MVRAM_EQUIPMENT_NFDS	0xC0		/* mask for # of floppies */
79 
80 /* NVRAM bytes 7 & 8: base memory size */
81 #define NVRAM_BASELO	(MC_NVRAM_START + 7)	/* low byte; RTC off. 0x15 */
82 #define NVRAM_BASEHI	(MC_NVRAM_START + 8)	/* high byte; RTC off. 0x16 */
83 
84 /* NVRAM bytes 9 & 10: extended memory size */
85 #define NVRAM_EXTLO	(MC_NVRAM_START + 9)	/* low byte; RTC off. 0x17 */
86 #define NVRAM_EXTHI	(MC_NVRAM_START + 10)	/* high byte; RTC off. 0x18 */
87 
88 /* NVRAM bytes 34 and 35: extended memory POSTed size */
89 #define NVRAM_PEXTLO	(MC_NVRAM_START + 34)	/* low byte; RTC off. 0x30 */
90 #define NVRAM_PEXTHI	(MC_NVRAM_START + 35)	/* high byte; RTC off. 0x31 */
91 
92 /* NVRAM byte 36: current century.  (please increment in Dec99!) */
93 #define NVRAM_CENTURY	(MC_NVRAM_START + 36)	/* RTC offset 0x32 */
94