pmap.h revision 1.40 1 /* $NetBSD: pmap.h,v 1.40 2002/09/22 07:53:45 chs Exp $ */
2
3 /*
4 * Copyright (c) 1987 Carnegie-Mellon University
5 * Copyright (c) 1992, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Ralph Campbell.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * @(#)pmap.h 8.1 (Berkeley) 6/10/93
40 */
41
42 #ifndef _PMAP_MACHINE_
43 #define _PMAP_MACHINE_
44
45 #include <mips/cpuregs.h> /* for KSEG0 below */
46
47 /*
48 * The user address space is 2Gb (0x0 - 0x80000000).
49 * User programs are laid out in memory as follows:
50 * address
51 * USRTEXT 0x00001000
52 * USRDATA USRTEXT + text_size
53 * USRSTACK 0x7FFFFFFF
54 *
55 * The user address space is mapped using a two level structure where
56 * virtual address bits 30..22 are used to index into a segment table which
57 * points to a page worth of PTEs (4096 page can hold 1024 PTEs).
58 * Bits 21..12 are then used to index a PTE which describes a page within
59 * a segment.
60 *
61 * The wired entries in the TLB will contain the following:
62 * 0-1 (UPAGES) for curproc user struct and kernel stack.
63 *
64 * Note: The kernel doesn't use the same data structures as user programs.
65 * All the PTE entries are stored in a single array in Sysmap which is
66 * dynamically allocated at boot time.
67 */
68
69 #define mips_trunc_seg(x) ((vaddr_t)(x) & ~SEGOFSET)
70 #define mips_round_seg(x) (((vaddr_t)(x) + SEGOFSET) & ~SEGOFSET)
71 #define pmap_segmap(m, v) ((m)->pm_segtab->seg_tab[((v) >> SEGSHIFT)])
72
73 #define PMAP_SEGTABSIZE 512
74
75 union pt_entry;
76
77 struct segtab {
78 union pt_entry *seg_tab[PMAP_SEGTABSIZE];
79 };
80
81 /*
82 * Machine dependent pmap structure.
83 */
84 typedef struct pmap {
85 int pm_count; /* pmap reference count */
86 struct simplelock pm_lock; /* lock on pmap */
87 struct pmap_statistics pm_stats; /* pmap statistics */
88 unsigned pm_asid; /* TLB address space tag */
89 unsigned pm_asidgen; /* its generation number */
90 struct segtab *pm_segtab; /* pointers to pages of PTEs */
91 } *pmap_t;
92
93 /*
94 * For each struct vm_page, there is a list of all currently valid virtual
95 * mappings of that page. An entry is a pv_entry_t, the list is pv_table.
96 * XXX really should do this as a part of the higher level code.
97 */
98 typedef struct pv_entry {
99 struct pv_entry *pv_next; /* next pv_entry */
100 struct pmap *pv_pmap; /* pmap where mapping lies */
101 vaddr_t pv_va; /* virtual address for mapping */
102 int pv_flags; /* some flags for the mapping */
103 } *pv_entry_t;
104
105 #define PV_UNCACHED 0x0001 /* page is mapped uncached */
106 #define PV_MODIFIED 0x0002 /* page has been modified */
107 #define PV_REFERENCED 0x0004 /* page has been recently referenced */
108
109
110 #ifdef _KERNEL
111
112 extern char *pmap_attributes; /* reference and modify bits */
113 extern struct pmap kernel_pmap_store;
114
115 #define pmap_kernel() (&kernel_pmap_store)
116 #define pmap_wired_count(pmap) ((pmap)->pm_stats.wired_count)
117 #define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count)
118
119 #define pmap_update(pmap) /* nothing (yet) */
120
121 static __inline void
122 pmap_remove_all(struct pmap *pmap)
123 {
124 /* Nothing. */
125 }
126
127 /*
128 * Bootstrap the system enough to run with virtual memory.
129 */
130 void pmap_bootstrap(void);
131
132 void pmap_set_modified(paddr_t);
133
134 void pmap_procwr(struct proc *, vaddr_t, size_t);
135 #define PMAP_NEED_PROCWR
136
137 /*
138 * pmap_prefer() helps reduce virtual-coherency exceptions in
139 * the virtually-indexed cache on mips3 CPUs.
140 */
141 #ifdef MIPS3_PLUS
142 #define PMAP_PREFER(pa, va) pmap_prefer((pa), (va))
143 void pmap_prefer(vaddr_t, vaddr_t *);
144 #endif /* MIPS3_PLUS */
145
146 #define PMAP_STEAL_MEMORY /* enable pmap_steal_memory() */
147
148 /*
149 * Alternate mapping hooks for pool pages. Avoids thrashing the TLB.
150 */
151 #define PMAP_MAP_POOLPAGE(pa) MIPS_PHYS_TO_KSEG0((pa))
152 #define PMAP_UNMAP_POOLPAGE(va) MIPS_KSEG0_TO_PHYS((va))
153
154 /*
155 * Select CCA to use for unmanaged pages.
156 */
157 #define PMAP_CCA_FOR_PA(pa) 2 /* uncached */
158
159 #endif /* _KERNEL */
160 #endif /* _PMAP_MACHINE_ */
161