param.h revision 757
1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 *	from: @(#)param.h	5.8 (Berkeley) 6/28/91
37 *	$Id: param.h,v 1.8 1993/11/07 17:42:58 wollman Exp $
38 */
39
40#ifndef _MACHINE_PARAM_H_
41#define _MACHINE_PARAM_H_ 1
42
43/*
44 * Machine dependent constants for Intel 386.
45 */
46
47#define MACHINE		"i386"
48#define MID_MACHINE	MID_I386
49
50/*
51 * Round p (pointer or byte index) up to a correctly-aligned value
52 * for all data types (int, long, ...).   The result is u_int and
53 * must be cast to any desired pointer type.
54 */
55#define ALIGNBYTES	(sizeof(int) - 1)
56#define ALIGN(p)	(((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
57
58/* XXX PGSHIFT and PG_SHIFT are two names for the same thing */
59#define PGSHIFT		12		/* LOG2(NBPG) */
60#define NBPG		(1 << PGSHIFT)	/* bytes/page */
61#define PGOFSET		(NBPG-1)	/* byte offset into page */
62#define NPTEPG		(NBPG/(sizeof (struct pte)))
63
64/* XXX PDRSHIFT and PD_SHIFT are two names for the same thing */
65#define PDRSHIFT	22		/* LOG2(NBPDR) */
66#define NBPDR		(1 << PDRSHIFT)	/* bytes/page dir */
67#define PDROFSET	(NBPDR-1)	/* byte offset into page dir */
68
69/*
70 * XXX This should really be KPTDPTDI << PDRSHIFT, but since KPTDPTDI is
71 * defined in pmap.h which is included after this we can't do that
72 * (YET!)
73 */
74#define KERNBASE	0xFE000000	/* start of kernel virtual */
75#define BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
76
77#define DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
78#define DEV_BSIZE	(1 << DEV_BSHIFT)
79
80#define BLKDEV_IOSIZE	2048
81#define MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
82
83#define CLSIZELOG2	0
84#define CLSIZE		(1 << CLSIZELOG2)
85
86/* NOTE: SSIZE, SINCR and UPAGES must be multiples of CLSIZE */
87#define SSIZE	1		/* initial stack size/NBPG */
88#define SINCR	1		/* increment of stack/NBPG */
89
90#define UPAGES	2		/* pages of u-area */
91
92/*
93 * Constants related to network buffer management.
94 * MCLBYTES must be no larger than CLBYTES (the software page size), and,
95 * on machines that exchange pages of input or output buffers with mbuf
96 * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
97 * of the hardware page size.
98 */
99#ifndef	MSIZE
100#define MSIZE		128		/* size of an mbuf */
101#endif	/* MSIZE */
102
103#ifndef	MCLSHIFT
104#define MCLSHIFT	11		/* convert bytes to m_buf clusters */
105#endif	/* MCLSHIFT */
106#define MCLBYTES	(1 << MCLSHIFT)	/* size of an m_buf cluster */
107#define MCLOFSET	(MCLBYTES - 1)	/* offset within an m_buf cluster */
108
109#ifndef NMBCLUSTERS
110#ifdef GATEWAY
111#define NMBCLUSTERS	512		/* map size, max cluster allocation */
112#else
113#define NMBCLUSTERS	256		/* map size, max cluster allocation */
114#endif	/* GATEWAY */
115#endif	/* NMBCLUSTERS */
116
117/*
118 * Some macros for units conversion
119 */
120/* Core clicks (4096 bytes) to segments and vice versa */
121#define ctos(x)	(x)
122#define stoc(x)	(x)
123
124/* Core clicks (4096 bytes) to disk blocks */
125#define ctod(x)	((x)<<(PGSHIFT-DEV_BSHIFT))
126#define dtoc(x)	((x)>>(PGSHIFT-DEV_BSHIFT))
127#define dtob(x)	((x)<<DEV_BSHIFT)
128
129/* clicks to bytes */
130#define ctob(x)	((x)<<PGSHIFT)
131
132/* bytes to clicks */
133#define btoc(x)	(((unsigned)(x)+(NBPG-1))>>PGSHIFT)
134
135#define btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
136	((unsigned)(bytes) >> DEV_BSHIFT)
137#define dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
138	((unsigned)(db) << DEV_BSHIFT)
139
140/*
141 * Map a ``block device block'' to a file system block.
142 * This should be device dependent, and will be if we
143 * add an entry to cdevsw/bdevsw for that purpose.
144 * For now though just use DEV_BSIZE.
145 */
146#define bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
147
148/*
149 * Mach derived conversion macros
150 */
151#define i386_round_pdr(x)	((((unsigned)(x)) + NBPDR - 1) & ~(NBPDR-1))
152#define i386_trunc_pdr(x)	((unsigned)(x) & ~(NBPDR-1))
153#define i386_round_page(x)	((((unsigned)(x)) + NBPG - 1) & ~(NBPG-1))
154#define i386_trunc_page(x)	((unsigned)(x) & ~(NBPG-1))
155#define i386_btod(x)		((unsigned)(x) >> PDRSHIFT)
156#define i386_dtob(x)		((unsigned)(x) << PDRSHIFT)
157#define i386_btop(x)		((unsigned)(x) >> PGSHIFT)
158#define i386_ptob(x)		((unsigned)(x) << PGSHIFT)
159
160/*
161 * phystokv stolen from SCSI device drivers and fixed to use KERNBASE
162 */
163#define PHYSTOKV(x)	(x | KERNBASE)
164#endif /* _MACHINE_PARAM_H_ */
165