1 /* $OpenBSD: param.h,v 1.40 2007/05/28 21:02:49 thib Exp $ */
2 /* $NetBSD: param.h,v 1.29 1996/03/04 05:04:26 cgd Exp $ */
3
4 /*-
5 * Copyright (c) 1990 The Regents of the University of California.
6 * 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 * @(#)param.h 5.8 (Berkeley) 6/28/91
36 */
37
38 /*
39 * Machine dependent constants for Intel 386.
40 */
41
42 #ifdef _KERNEL
43 #ifdef _LOCORE
44 #include <machine/psl.h>
45 #else
46 #include <machine/cpu.h>
47 #endif
48 #endif
49
50 #define _MACHINE i386
51 #define MACHINE "i386"
52 #define _MACHINE_ARCH i386
53 #define MACHINE_ARCH "i386"
54 #define MID_MACHINE MID_I386
55
56 /*
57 * Round p (pointer or byte index) up to a correctly-aligned value
58 * for all data types (int, long, ...). The result is u_int and
59 * must be cast to any desired pointer type.
60 *
61 * ALIGNED_POINTER is a boolean macro that checks whether an address
62 * is valid to fetch data elements of type t from on this architecture.
63 * This does not reflect the optimal alignment, just the possibility
64 * (within reasonable limits).
65 */
66 #define ALIGNBYTES (sizeof(int) - 1)
67 #define ALIGN(p) (((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
68 #define ALIGNED_POINTER(p,t) 1
69
70 #define PGSHIFT 12 /* LOG2(NBPG) */
71 #define NBPG (1 << PGSHIFT) /* bytes/page */
72 #define PGOFSET (NBPG-1) /* byte offset into page */
73
74 #define PAGE_SHIFT 12
75 #define PAGE_SIZE (1 << PAGE_SHIFT)
76 #define PAGE_MASK (PAGE_SIZE - 1)
77
78 #define NPTEPG (NBPG/(sizeof (pt_entry_t)))
79
80 /*
81 * Start of kernel virtual space. Remember to alter the memory and
82 * page table layout description in pmap.h when changing this.
83 */
84 #define KERNBASE 0xd0000000
85
86 #define KERNTEXTOFF (KERNBASE+0x200000) /* start of kernel text */
87
88 #define DEV_BSHIFT 9 /* log2(DEV_BSIZE) */
89 #define DEV_BSIZE (1 << DEV_BSHIFT)
90 #define BLKDEV_IOSIZE 2048
91 #ifndef MAXPHYS
92 #define MAXPHYS (64 * 1024) /* max raw I/O transfer size */
93 #endif
94
95 #define UPAGES 2 /* pages of u-area */
96 #define USPACE (UPAGES * NBPG) /* total size of u-area */
97 #define USPACE_ALIGN (0) /* u-area alignment 0-none */
98
99 #ifndef MSGBUFSIZE
100 #define MSGBUFSIZE 4*NBPG /* default message buffer size */
101 #endif
102
103 /*
104 * Constants related to network buffer management.
105 */
106 #define NMBCLUSTERS 6144 /* map size, max cluster allocation */
107
108 /*
109 * Minimum and maximum sizes of the kernel malloc arena in PAGE_SIZE-sized
110 * logical pages.
111 */
112 #define NKMEMPAGES_MIN_DEFAULT ((8 * 1024 * 1024) >> PAGE_SHIFT)
113 #define NKMEMPAGES_MAX_DEFAULT ((64 * 1024 * 1024) >> PAGE_SHIFT)
114
115 /* pages ("clicks") to disk blocks */
116 #define ctod(x) ((x) << (PGSHIFT - DEV_BSHIFT))
117 #define dtoc(x) ((x) >> (PGSHIFT - DEV_BSHIFT))
118
119 /* bytes to pages */
120 #define ctob(x) ((x) << PGSHIFT)
121 #define btoc(x) (((x) + PGOFSET) >> PGSHIFT)
122
123 /* bytes to disk blocks */
124 #define dbtob(x) ((x) << DEV_BSHIFT)
125 #define btodb(x) ((x) >> DEV_BSHIFT)
126
127 /*
128 * Mach derived conversion macros
129 */
130 #define i386_round_pdr(x) ((((unsigned)(x)) + PDOFSET) & ~PDOFSET)
131 #define i386_trunc_pdr(x) ((unsigned)(x) & ~PDOFSET)