xref: /csrg-svn/sys/tahoe/include/param.h (revision 40212)
1 /*
2  * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)param.h	7.4 (Berkeley) 02/23/90
7  */
8 
9 /*
10  * Machine dependent constants for TAHOE.
11  */
12 #define	MACHINE	"tahoe"
13 
14 #ifndef BYTE_ORDER
15 #include <machine/endian.h>
16 #endif
17 
18 #include <machine/machlimits.h>
19 
20 #define	NBPG		1024		/* bytes/page */
21 #define	PGOFSET		(NBPG-1)	/* byte offset into page */
22 #define	PGSHIFT		10		/* LOG2(NBPG) */
23 #define	NPTEPG		(NBPG/(sizeof (struct pte)))
24 
25 #define	KERNBASE	0xc0000000	/* start of kernel virtual */
26 #define	KERNTEXTOFF	(KERNBASE + 0x800)	/* start of kernel text */
27 #define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
28 
29 #define	DEV_BSIZE	1024
30 #define	DEV_BSHIFT	10		/* log2(DEV_BSIZE) */
31 #define BLKDEV_IOSIZE	1024		/* NBPG for physical controllers */
32 #define	MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
33 
34 #define	CLSIZE		1
35 #define	CLSIZELOG2	0
36 
37 #define	SSIZE		2		/* initial stack size/NBPG */
38 #define	SINCR		2		/* increment of stack/NBPG */
39 #define	UPAGES		8		/* pages of u-area (2 stack pages) */
40 
41 /*
42  * Constants related to network buffer management.
43  * MCLBYTES must be no larger than CLBYTES (the software page size), and,
44  * on machines that exchange pages of input or output buffers with mbuf
45  * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
46  * of the hardware page size.
47  */
48 #define	MSIZE		128		/* size of an mbuf */
49 #define	MAPPED_MBUFS			/* can do scatter-gather I/O */
50 #if CLBYTES > 1024
51 #define	MCLBYTES	1024
52 #define	MCLSHIFT	10
53 #define	MCLOFSET	(MCLBYTES - 1)
54 #else
55 #define	MCLBYTES	CLBYTES
56 #define	MCLSHIFT	CLSHIFT
57 #define	MCLOFSET	CLOFSET
58 #endif
59 #ifdef GATEWAY
60 #define	NMBCLUSTERS	512		/* map size, max cluster allocation */
61 #else
62 #define	NMBCLUSTERS	256		/* map size, max cluster allocation */
63 #endif
64 
65 #define	MAXCKEY	255		/* maximal allowed code key */
66 #define	MAXDKEY	255		/* maximal allowed data key */
67 #define	NCKEY	(MAXCKEY+1)	/* # code keys, including 0 (reserved) */
68 #define	NDKEY	(MAXDKEY+1)	/* # data keys, including 0 (reserved) */
69 
70 /*
71  * Some macros for units conversion
72  */
73 /* Core clicks (1024 bytes) to segments and vice versa */
74 #define	ctos(x)	(x)
75 #define	stoc(x)	(x)
76 
77 /* Core clicks (1024 bytes) to disk blocks */
78 #define	ctod(x)	(x)
79 #define	dtoc(x)	(x)
80 #define	dtob(x)	((x)<<PGSHIFT)
81 
82 /* clicks to bytes */
83 #define	ctob(x)	((x)<<PGSHIFT)
84 
85 /* bytes to clicks */
86 #define	btoc(x)	((((unsigned)(x)+NBPG-1) >> PGSHIFT))
87 
88 #define	btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
89 	((unsigned)(bytes) >> DEV_BSHIFT)
90 #define	dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
91 	((unsigned)(db) << DEV_BSHIFT)
92 
93 /*
94  * Map a ``block device block'' to a file system block.
95  * This should be device dependent, and will be if we
96  * add an entry to cdevsw/bdevsw for that purpose.
97  * For now though just use DEV_BSIZE.
98  */
99 #define	bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
100 
101 /*
102  * Macros to decode processor status word.
103  */
104 #define	USERMODE(ps)	(((ps) & PSL_CURMOD) == PSL_CURMOD)
105 #define	BASEPRI(ps)	(((ps) & PSL_IPL) == 0)
106 
107 #define	DELAY(n)	{ register int N = 3*(n); while (--N > 0); }
108