xref: /netbsd-src/sys/arch/i386/include/param.h (revision 6ea46cb5e46c49111a6ecf3bcbe3c7e2730fe9f6)
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 1.20 1994/08/24 19:32:36 mycroft Exp $
38  */
39 
40 /*
41  * Machine dependent constants for Intel 386.
42  */
43 
44 #ifdef KERNEL
45 #ifdef LOCORE
46 #include <machine/psl.h>
47 #else
48 #include <machine/cpu.h>
49 #endif
50 #endif
51 
52 #define MACHINE		"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 #define ALIGNBYTES	(sizeof(int) - 1)
62 #define ALIGN(p)	(((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
63 
64 #define	PGSHIFT		12		/* LOG2(NBPG) */
65 #define	NBPG		(1 << PGSHIFT)	/* bytes/page */
66 #define	PGOFSET		(NBPG-1)	/* byte offset into page */
67 #define	NPTEPG		(NBPG/(sizeof (pt_entry_t)))
68 
69 #define	KERNBASE	0xf8000000	/* start of kernel virtual space */
70 #define	KERNSIZE	0x01800000	/* size of kernel virtual space */
71 #define	KERNTEXTOFF	0xf8100000	/* start of kernel text */
72 #define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
73 
74 #define	DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
75 #define	DEV_BSIZE	(1 << DEV_BSHIFT)
76 #define	BLKDEV_IOSIZE	2048
77 #define	MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
78 
79 #define	CLSIZELOG2	0
80 #define	CLSIZE		(1 << CLSIZELOG2)
81 
82 /* NOTE: SSIZE, SINCR and UPAGES must be multiples of CLSIZE */
83 #define	SSIZE	1		/* initial stack size/NBPG */
84 #define	SINCR	1		/* increment of stack/NBPG */
85 #define	UPAGES	2		/* pages of u-area */
86 #define	USPACE	(UPAGES * NBPG)	/* total size of u-area */
87 
88 /*
89  * Constants related to network buffer management.
90  * MCLBYTES must be no larger than CLBYTES (the software page size), and,
91  * on machines that exchange pages of input or output buffers with mbuf
92  * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
93  * of the hardware page size.
94  */
95 #define	MSIZE		128		/* size of an mbuf */
96 #define	MCLSHIFT	11		/* convert bytes to m_buf clusters */
97 #define	MCLBYTES	(1 << MCLSHIFT)	/* size of a m_buf cluster */
98 #define	MCLOFSET	(MCLBYTES - 1)	/* offset within a m_buf cluster */
99 
100 #ifndef NMBCLUSTERS
101 #ifdef GATEWAY
102 #define	NMBCLUSTERS	512		/* map size, max cluster allocation */
103 #else
104 #define	NMBCLUSTERS	256		/* map size, max cluster allocation */
105 #endif
106 #endif
107 
108 /*
109  * Size of kernel malloc arena in CLBYTES-sized logical pages
110  */
111 #ifndef NKMEMCLUSTERS
112 #define	NKMEMCLUSTERS	(6 * 1024 * 1024 / CLBYTES)
113 #endif
114 
115 /*
116  * The disklabel is in block 0 or 1, possibly offset from the beginning
117  * to leave room for a bootstrap, etc.
118  */
119 
120 #define LABELSECTOR	1			/* sector containing label */
121 #define LABELOFFSET	0			/* offset of label in sector */
122 
123 /* pages ("clicks") (4096 bytes) to disk blocks */
124 #define	ctod(x)	((x) << (PGSHIFT - DEV_BSHIFT))
125 #define	dtoc(x)	((x) >> (PGSHIFT - DEV_BSHIFT))
126 #define	dtob(x)	((x) << DEV_BSHIFT)
127 
128 #define	ctob(x)	((x) << PGSHIFT)
129 
130 /* bytes to pages */
131 #define	btoc(x)	(((unsigned)(x) + PGOFSET) >> PGSHIFT)
132 
133 #define	btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
134 	((unsigned)(bytes) >> DEV_BSHIFT)
135 #define	dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
136 	((unsigned)(db) << DEV_BSHIFT)
137 
138 /*
139  * Map a ``block device block'' to a file system block.
140  * This should be device dependent, and should use the bsize
141  * field from the disk label.
142  * For now though just use DEV_BSIZE.
143  */
144 #define	bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE / DEV_BSIZE))
145 
146 /*
147  * Mach derived conversion macros
148  */
149 #define	i386_round_pdr(x)	((((unsigned)(x)) + PDOFSET) & ~PDOFSET)
150 #define	i386_trunc_pdr(x)	((unsigned)(x) & ~PDOFSET)
151 #define	i386_btod(x)		((unsigned)(x) >> PDSHIFT)
152 #define	i386_dtob(x)		((unsigned)(x) << PDSHIFT)
153 #define	i386_round_page(x)	((((unsigned)(x)) + PGOFSET) & ~PGOFSET)
154 #define	i386_trunc_page(x)	((unsigned)(x) & ~PGOFSET)
155 #define	i386_btop(x)		((unsigned)(x) >> PGSHIFT)
156 #define	i386_ptob(x)		((unsigned)(x) << PGSHIFT)
157