xref: /freebsd/sys/i386/include/specialreg.h (revision e627b39baccd1ec9129690167cf5e6d860509655)
1 /*-
2  * Copyright (c) 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	from: @(#)specialreg.h	7.1 (Berkeley) 5/9/91
34  *	$Id: specialreg.h,v 1.8 1996/01/30 22:55:06 mpp Exp $
35  */
36 
37 #ifndef _MACHINE_SPECIALREG_H_
38 #define	_MACHINE_SPECIALREG_H_
39 
40 /*
41  * Bits in 386 special registers:
42  */
43 #define	CR0_PE	0x00000001	/* Protected mode Enable */
44 #define	CR0_MP	0x00000002	/* "Math" Present (NPX or NPX emulator) */
45 #ifdef notused
46 #define	CR0_EM	0x00000004	/* EMulate non-NPX coproc. (trap ESC only) */
47 #endif
48 #define	CR0_TS	0x00000008	/* Task Switched (if MP, trap ESC and WAIT) */
49 #ifdef notused
50 #define	CR0_ET	0x00000010	/* Extension Type (387 (if set) vs 287) */
51 #endif
52 #define	CR0_PG	0x80000000	/* PaGing enable */
53 
54 /*
55  * Bits in 486 special registers:
56  */
57 #define CR0_NE	0x00000020	/* Numeric Error enable (EX16 vs IRQ13) */
58 #define CR0_WP	0x00010000	/* Write Protect (honor page protect in all modes) */
59 #define CR0_AM	0x00040000	/* Alignment Mask (set to enable AC flag) */
60 #define CR0_NW  0x20000000      /* Not Write-through */
61 #define CR0_CD  0x40000000      /* Cache Disable */
62 
63 /*
64  * Cyrix 486 DLC special registers, accessible as IO ports.
65  */
66 #define CCR0	0xc0		/* configuration control register 0 */
67 #define CCR0_NC0	0x01	/* first 64K of each 1M memory region is
68 				   non-cacheable */
69 #define CCR0_NC1	0x02	/* 640K-1M region is non-cacheable */
70 #define CCR0_A20M	0x04	/* enables A20M# input pin */
71 #define CCR0_KEN	0x08	/* enables KEN# input pin */
72 #define CCR0_FLUSH	0x10	/* enables FLUSH# input pin */
73 #define CCR0_BARB	0x20	/* flushes internal cache when entering hold
74 				   state */
75 #define CCR0_CO		0x40	/* cache org: 1=direct mapped, 0=2x set assoc */
76 #define CCR0_SUSPEND	0x80	/* enables SUSP# and SUSPA# pins */
77 
78 #define CCR1	0xc1		/* configuration control register 1 */
79 #define CCR1_RPL	0x01	/* enables RPLSET and RPLVAL# pins */
80 /* the remaining 7 bits of this register are reserved */
81 
82 /*
83  * the following four 3-byte registers control the non-cacheable regions.
84  * These registers must be written as three separate bytes.
85  *
86  * NCRx+0: A31-A24 of starting address
87  * NCRx+1: A23-A16 of starting address
88  * NCRx+2: A15-A12 of starting address | NCR_SIZE_xx.
89  *
90  * The non-cacheable region's starting address must be aligned to the
91  * size indicated by the NCR_SIZE_xx field.
92  */
93 #define NCR1	0xc4
94 #define NCR2	0xc7
95 #define NCR3	0xca
96 #define NCR4	0xcd
97 
98 #define NCR_SIZE_0K	0
99 #define NCR_SIZE_4K	1
100 #define NCR_SIZE_8K	2
101 #define NCR_SIZE_16K	3
102 #define NCR_SIZE_32K	4
103 #define NCR_SIZE_64K	5
104 #define NCR_SIZE_128K	6
105 #define NCR_SIZE_256K	7
106 #define NCR_SIZE_512K	8
107 #define NCR_SIZE_1M	9
108 #define NCR_SIZE_2M	10
109 #define NCR_SIZE_4M	11
110 #define NCR_SIZE_8M	12
111 #define NCR_SIZE_16M	13
112 #define NCR_SIZE_32M	14
113 #define NCR_SIZE_4G	15
114 
115 #endif /* !_MACHINE_SPECIALREG_H_ */
116