xref: /original-bsd/sys/tahoe/include/param.h (revision 188f7363)
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	7.5 (Berkeley) 04/03/90
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 /*
21  * Round p (pointer or byte index) up to a correctly-aligned value
22  * for all data types (int, long, ...).   The result is u_int and
23  * must be cast to any desired pointer type.
24  */
25 #define	ALIGN(p)	(((u_int)(p) + (sizeof(int) - 1)) &~ (sizeof(int) - 1))
26 
27 #define	NBPG		1024		/* bytes/page */
28 #define	PGOFSET		(NBPG-1)	/* byte offset into page */
29 #define	PGSHIFT		10		/* LOG2(NBPG) */
30 #define	NPTEPG		(NBPG/(sizeof (struct pte)))
31 
32 #define	KERNBASE	0xc0000000	/* start of kernel virtual */
33 #define	KERNTEXTOFF	(KERNBASE + 0x800)	/* start of kernel text */
34 #define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
35 
36 #define	DEV_BSIZE	1024
37 #define	DEV_BSHIFT	10		/* log2(DEV_BSIZE) */
38 #define BLKDEV_IOSIZE	1024		/* NBPG for physical controllers */
39 #define	MAXPHYS		(64 * 1024)	/* max raw I/O transfer size */
40 
41 #define	CLSIZE		1
42 #define	CLSIZELOG2	0
43 
44 #define	SSIZE		2		/* initial stack size/NBPG */
45 #define	SINCR		2		/* increment of stack/NBPG */
46 #define	UPAGES		8		/* pages of u-area (2 stack pages) */
47 
48 /*
49  * Constants related to network buffer management.
50  * MCLBYTES must be no larger than CLBYTES (the software page size), and,
51  * on machines that exchange pages of input or output buffers with mbuf
52  * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
53  * of the hardware page size.
54  */
55 #define	MSIZE		128		/* size of an mbuf */
56 #define	MAPPED_MBUFS			/* can do scatter-gather I/O */
57 #if CLBYTES > 1024
58 #define	MCLBYTES	1024
59 #define	MCLSHIFT	10
60 #define	MCLOFSET	(MCLBYTES - 1)
61 #else
62 #define	MCLBYTES	CLBYTES
63 #define	MCLSHIFT	CLSHIFT
64 #define	MCLOFSET	CLOFSET
65 #endif
66 #ifdef GATEWAY
67 #define	NMBCLUSTERS	512		/* map size, max cluster allocation */
68 #else
69 #define	NMBCLUSTERS	256		/* map size, max cluster allocation */
70 #endif
71 
72 #define	MAXCKEY	255		/* maximal allowed code key */
73 #define	MAXDKEY	255		/* maximal allowed data key */
74 #define	NCKEY	(MAXCKEY+1)	/* # code keys, including 0 (reserved) */
75 #define	NDKEY	(MAXDKEY+1)	/* # data keys, including 0 (reserved) */
76 
77 /*
78  * Some macros for units conversion
79  */
80 /* Core clicks (1024 bytes) to segments and vice versa */
81 #define	ctos(x)	(x)
82 #define	stoc(x)	(x)
83 
84 /* Core clicks (1024 bytes) to disk blocks */
85 #define	ctod(x)	(x)
86 #define	dtoc(x)	(x)
87 #define	dtob(x)	((x)<<PGSHIFT)
88 
89 /* clicks to bytes */
90 #define	ctob(x)	((x)<<PGSHIFT)
91 
92 /* bytes to clicks */
93 #define	btoc(x)	((((unsigned)(x)+NBPG-1) >> PGSHIFT))
94 
95 #define	btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
96 	((unsigned)(bytes) >> DEV_BSHIFT)
97 #define	dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
98 	((unsigned)(db) << DEV_BSHIFT)
99 
100 /*
101  * Map a ``block device block'' to a file system block.
102  * This should be device dependent, and will be if we
103  * add an entry to cdevsw/bdevsw for that purpose.
104  * For now though just use DEV_BSIZE.
105  */
106 #define	bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
107 
108 /*
109  * Macros to decode processor status word.
110  */
111 #define	USERMODE(ps)	(((ps) & PSL_CURMOD) == PSL_CURMOD)
112 #define	BASEPRI(ps)	(((ps) & PSL_IPL) == 0)
113 
114 #define	DELAY(n)	{ register int N = 3*(n); while (--N > 0); }
115