xref: /csrg-svn/sys/vax/include/param.h (revision 40721)
1 /*
2  * Copyright (c) 1982, 1986 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	7.15 (Berkeley) 04/03/90
7  */
8 
9 /*
10  * Machine dependent constants for VAX.
11  */
12 #define	MACHINE	"vax"
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		512		/* bytes/page */
28 #define	PGOFSET		(NBPG-1)	/* byte offset into page */
29 #define	PGSHIFT		9		/* LOG2(NBPG) */
30 #define	NPTEPG		(NBPG/(sizeof (struct pte)))
31 
32 #define	KERNBASE	0x80000000	/* start of kernel virtual */
33 #define	KERNTEXTOFF	KERNBASE	/* start of kernel text */
34 #define	BTOPKERNBASE	((u_long)KERNBASE >> PGSHIFT)
35 
36 #define	DEV_BSIZE	512
37 #define	DEV_BSHIFT	9		/* log2(DEV_BSIZE) */
38 #define BLKDEV_IOSIZE	2048
39 #define	MAXPHYS		(63 * 1024)	/* max raw I/O transfer size */
40 
41 #define	CLSIZE		2
42 #define	CLSIZELOG2	1
43 
44 #define	SSIZE		4		/* initial stack size/NBPG */
45 #define	SINCR		4		/* increment of stack/NBPG */
46 
47 #define	UPAGES		16		/* pages of u-area */
48 
49 /*
50  * Constants related to network buffer management.
51  * MCLBYTES must be no larger than CLBYTES (the software page size), and,
52  * on machines that exchange pages of input or output buffers with mbuf
53  * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
54  * of the hardware page size.
55  */
56 #define	MSIZE		128		/* size of an mbuf */
57 #define	MAPPED_MBUFS			/* can do scatter-gather I/O */
58 #if CLBYTES > 1024
59 #define	MCLBYTES	1024
60 #define	MCLSHIFT	10
61 #define	MCLOFSET	(MCLBYTES - 1)
62 #else
63 #define	MCLBYTES	CLBYTES
64 #define	MCLSHIFT	CLSHIFT
65 #define	MCLOFSET	CLOFSET
66 #endif
67 #ifdef GATEWAY
68 #define	NMBCLUSTERS	512		/* map size, max cluster allocation */
69 #else
70 #define	NMBCLUSTERS	256		/* map size, max cluster allocation */
71 #endif
72 
73 /*
74  * Some macros for units conversion
75  */
76 /* Core clicks (512 bytes) to segments and vice versa */
77 #define	ctos(x)	(x)
78 #define	stoc(x)	(x)
79 
80 /* Core clicks (512 bytes) to disk blocks */
81 #define	ctod(x)	(x)
82 #define	dtoc(x)	(x)
83 #define	dtob(x)	((x)<<PGSHIFT)
84 
85 /* clicks to bytes */
86 #define	ctob(x)	((x)<<9)
87 
88 /* bytes to clicks */
89 #define	btoc(x)	((((unsigned)(x)+511)>>9))
90 
91 #define	btodb(bytes)	 		/* calculates (bytes / DEV_BSIZE) */ \
92 	((unsigned)(bytes) >> DEV_BSHIFT)
93 #define	dbtob(db)			/* calculates (db * DEV_BSIZE) */ \
94 	((unsigned)(db) << DEV_BSHIFT)
95 
96 /*
97  * Map a ``block device block'' to a file system block.
98  * This should be device dependent, and will be if we
99  * add an entry to cdevsw/bdevsw for that purpose.
100  * For now though just use DEV_BSIZE.
101  */
102 #define	bdbtofsb(bn)	((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
103 
104 /*
105  * Macros to decode processor status word.
106  */
107 #define	USERMODE(ps)	(((ps) & PSL_CURMOD) == PSL_CURMOD)
108 #define	BASEPRI(ps)	(((ps) & PSL_IPL) == 0)
109 
110 #ifdef KERNEL
111 #ifndef LOCORE
112 int	cpuspeed;
113 #define	DELAY(n)	{ register int N = cpuspeed * (n); while (--N > 0); }
114 #endif
115 
116 #else KERNEL
117 #define	DELAY(n)	{ register int N = (n); while (--N > 0); }
118 #endif KERNEL
119