xref: /freebsd/sys/i386/include/param.h (revision eda14cbc264d6969b02f2b1994cef11148e914f1)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * William Jolitz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	from: @(#)param.h	5.8 (Berkeley) 6/28/91
35  * $FreeBSD$
36  */
37 
38 
39 #ifndef _I386_INCLUDE_PARAM_H_
40 #define	_I386_INCLUDE_PARAM_H_
41 
42 #include <machine/_align.h>
43 
44 /*
45  * Machine dependent constants for Intel 386.
46  */
47 
48 
49 #define __HAVE_ACPI
50 #define	__HAVE_PIR
51 #define __PCI_REROUTE_INTERRUPT
52 
53 #ifndef MACHINE
54 #define MACHINE		"i386"
55 #endif
56 #ifndef MACHINE_ARCH
57 #define	MACHINE_ARCH	"i386"
58 #endif
59 #define MID_MACHINE	MID_I386
60 
61 #ifdef SMP
62 #ifndef MAXCPU
63 #define MAXCPU		32
64 #endif
65 #else
66 #define MAXCPU		1
67 #endif
68 
69 #ifndef MAXMEMDOM
70 #define	MAXMEMDOM	1
71 #endif
72 
73 #define ALIGNBYTES	_ALIGNBYTES
74 #define ALIGN(p)	_ALIGN(p)
75 /*
76  * ALIGNED_POINTER is a boolean macro that checks whether an address
77  * is valid to fetch data elements of type t from on this architecture.
78  * This does not reflect the optimal alignment, just the possibility
79  * (within reasonable limits).
80  */
81 #define	ALIGNED_POINTER(p, t)	1
82 
83 /*
84  * CACHE_LINE_SIZE is the compile-time maximum cache line size for an
85  * architecture.  It should be used with appropriate caution.
86  */
87 #define	CACHE_LINE_SHIFT	6
88 #define	CACHE_LINE_SIZE		(1 << CACHE_LINE_SHIFT)
89 
90 #define PAGE_SHIFT	12		/* LOG2(PAGE_SIZE) */
91 #define PAGE_SIZE	(1 << PAGE_SHIFT)	/* bytes/page */
92 #define PAGE_MASK	(PAGE_SIZE - 1)
93 #define NPTEPG		(PAGE_SIZE / sizeof(pt_entry_t))
94 
95 /* Size in bytes of the page directory */
96 #define NBPTD		(NPGPTD << PAGE_SHIFT)
97 /* Number of PDEs in page directory, 2048 for PAE, 1024 for non-PAE */
98 #define NPDEPTD		(NBPTD / sizeof(pd_entry_t))
99 /* Number of PDEs in one page of the page directory, 512 vs. 1024 */
100 #define NPDEPG		(PAGE_SIZE / sizeof(pd_entry_t))
101 #define PDRMASK		(NBPDR - 1)
102 #ifndef PDRSHIFT
103 #define	PDRSHIFT	i386_pmap_PDRSHIFT
104 #endif
105 #ifndef NBPDR
106 #define NBPDR		(1 << PDRSHIFT)	/* bytes/page dir */
107 #endif
108 
109 #define	MAXPAGESIZES	2	/* maximum number of supported page sizes */
110 
111 #define IOPAGES	2		/* pages of i/o permission bitmap */
112 
113 #ifndef KSTACK_PAGES
114 #define KSTACK_PAGES 4		/* Includes pcb! */
115 #endif
116 #define KSTACK_GUARD_PAGES 1	/* pages of kstack guard; 0 disables */
117 #if KSTACK_PAGES < 4
118 #define	TD0_KSTACK_PAGES 4
119 #else
120 #define	TD0_KSTACK_PAGES KSTACK_PAGES
121 #endif
122 
123 /*
124  * Ceiling on amount of swblock kva space, can be changed via
125  * the kern.maxswzone /boot/loader.conf variable.
126  *
127  * 276 is sizeof(struct swblock), but we do not always have a definition
128  * in scope for struct swblock, so we have to hardcode it.  Each struct
129  * swblock holds metadata for 32 pages, so in theory, this is enough for
130  * 16 GB of swap.  In practice, however, the usable amount is considerably
131  * lower due to fragmentation.
132  */
133 #ifndef VM_SWZONE_SIZE_MAX
134 #define VM_SWZONE_SIZE_MAX	(276 * 128 * 1024)
135 #endif
136 
137 /*
138  * Ceiling on size of buffer cache (really only effects write queueing,
139  * the VM page cache is not effected), can be changed via
140  * the kern.maxbcache /boot/loader.conf variable.
141  *
142  * The value is equal to the size of the auto-tuned buffer map for
143  * the machine with 4GB of RAM, see vfs_bio.c:kern_vfs_bio_buffer_alloc().
144  */
145 #ifndef VM_BCACHE_SIZE_MAX
146 #define VM_BCACHE_SIZE_MAX	(7224 * 16 * 1024)
147 #endif
148 
149 /*
150  * Mach derived conversion macros
151  */
152 #define trunc_page(x)		((x) & ~PAGE_MASK)
153 #define round_page(x)		(((x) + PAGE_MASK) & ~PAGE_MASK)
154 #define trunc_4mpage(x)		((x) & ~PDRMASK)
155 #define round_4mpage(x)		((((x)) + PDRMASK) & ~PDRMASK)
156 
157 #define atop(x)			((x) >> PAGE_SHIFT)
158 #define ptoa(x)			((x) << PAGE_SHIFT)
159 
160 #define i386_btop(x)		((x) >> PAGE_SHIFT)
161 #define i386_ptob(x)		((x) << PAGE_SHIFT)
162 
163 #define	pgtok(x)		((x) * (PAGE_SIZE / 1024))
164 
165 #define INKERNEL(va)		(TRUE)
166 
167 #endif /* !_I386_INCLUDE_PARAM_H_ */
168