aboutsummaryrefslogtreecommitdiff
path: root/include/asm-mips/pgtable-bits.h
blob: 60e2f9338fcd6a6bd96adc064dad82eb8a763e2f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1994 - 2002 by Ralf Baechle
 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
 * Copyright (C) 2002  Maciej W. Rozycki
 */
#ifndef _ASM_PGTABLE_BITS_H
#define _ASM_PGTABLE_BITS_H


/*
 * Note that we shift the lower 32bits of each EntryLo[01] entry
 * 6 bits to the left. That way we can convert the PFN into the
 * physical address by a single 'and' operation and gain 6 additional
 * bits for storing information which isn't present in a normal
 * MIPS page table.
 *
 * Similar to the Alpha port, we need to keep track of the ref
 * and mod bits in software.  We have a software "yeah you can read
 * from this page" bit, and a hardware one which actually lets the
 * process read from the page.  On the same token we have a software
 * writable bit and the real hardware one which actually lets the
 * process write to the page, this keeps a mod bit via the hardware
 * dirty bit.
 *
 * Certain revisions of the R4000 and R5000 have a bug where if a
 * certain sequence occurs in the last 3 instructions of an executable
 * page, and the following page is not mapped, the cpu can do
 * unpredictable things.  The code (when it is written) to deal with
 * this problem will be in the update_mmu_cache() code for the r4k.
 */
#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)

#define _PAGE_PRESENT               (1<<6)  /* implemented in software */
#define _PAGE_READ                  (1<<7)  /* implemented in software */
#define _PAGE_WRITE                 (1<<8)  /* implemented in software */
#define _PAGE_ACCESSED              (1<<9)  /* implemented in software */
#define _PAGE_MODIFIED              (1<<10) /* implemented in software */
#define _PAGE_FILE                  (1<<10) /* set:pagecache unset:swap */

#define _PAGE_R4KBUG                (1<<0)  /* workaround for r4k bug  */
#define _PAGE_GLOBAL                (1<<0)
#define _PAGE_VALID                 (1<<1)
#define _PAGE_SILENT_READ           (1<<1)  /* synonym                 */
#define _PAGE_DIRTY                 (1<<2)  /* The MIPS dirty bit      */
#define _PAGE_SILENT_WRITE          (1<<2)
#define _CACHE_SHIFT                3
#define _CACHE_MASK                 (7<<3)

#else

#define _PAGE_PRESENT               (1<<0)  /* implemented in software */
#define _PAGE_READ                  (1<<1)  /* implemented in software */
#define _PAGE_WRITE                 (1<<2)  /* implemented in software */
#define _PAGE_ACCESSED              (1<<3)  /* implemented in software */
#define _PAGE_MODIFIED              (1<<4)  /* implemented in software */
#define _PAGE_FILE                  (1<<4)  /* set:pagecache unset:swap */

#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)

#define _PAGE_GLOBAL                (1<<8)
#define _PAGE_VALID                 (1<<9)
#define _PAGE_SILENT_READ           (1<<9)  /* synonym                 */
#define _PAGE_DIRTY                 (1<<10) /* The MIPS dirty bit      */
#define _PAGE_SILENT_WRITE          (1<<10)
#define _CACHE_UNCACHED             (1<<11)
#define _CACHE_MASK                 (1<<11)

#else

#define _PAGE_R4KBUG                (1<<5)  /* workaround for r4k bug  */
#define _PAGE_GLOBAL                (1<<6)
#define _PAGE_VALID                 (1<<7)
#define _PAGE_SILENT_READ           (1<<7)  /* synonym                 */
#define _PAGE_DIRTY                 (1<<8)  /* The MIPS dirty bit      */
#define _PAGE_SILENT_WRITE          (1<<8)
#define _CACHE_SHIFT		    9
#define _CACHE_MASK                 (7<<9)

#endif
#endif /* defined(CONFIG_64BIT_PHYS_ADDR && defined(CONFIG_CPU_MIPS32) */


/*
 * Cache attributes
 */
#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)

#define _CACHE_CACHABLE_NONCOHERENT 0

#elif defined(CONFIG_CPU_SB1)

/* No penalty for being coherent on the SB1, so just
   use it for "noncoherent" spaces, too.  Shouldn't hurt. */

#define _CACHE_UNCACHED             (2<<_CACHE_SHIFT)
#define _CACHE_CACHABLE_COW         (5<<_CACHE_SHIFT)
#define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
#define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT)

#elif defined(CONFIG_CPU_RM9000)

#define _CACHE_WT		    (0<<_CACHE_SHIFT)
#define _CACHE_WTWA		    (1<<_CACHE_SHIFT)
#define _CACHE_UC_B		    (2<<_CACHE_SHIFT)
#define _CACHE_WB		    (3<<_CACHE_SHIFT)
#define _CACHE_CWBEA		    (4<<_CACHE_SHIFT)
#define _CACHE_CWB		    (5<<_CACHE_SHIFT)
#define _CACHE_UCNB		    (6<<_CACHE_SHIFT)
#define _CACHE_FPC		    (7<<_CACHE_SHIFT)

#define _CACHE_UNCACHED		    _CACHE_UC_B
#define _CACHE_CACHABLE_NONCOHERENT _CACHE_WB

#else

#define _CACHE_CACHABLE_NO_WA	    (0<<_CACHE_SHIFT)  /* R4600 only      */
#define _CACHE_CACHABLE_WA	    (1<<_CACHE_SHIFT)  /* R4600 only      */
#define _CACHE_UNCACHED             (2<<_CACHE_SHIFT)  /* R4[0246]00      */
#define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT)  /* R4[0246]00      */
#define _CACHE_CACHABLE_CE          (4<<_CACHE_SHIFT)  /* R4[04]00MC only */
#define _CACHE_CACHABLE_COW         (5<<_CACHE_SHIFT)  /* R4[04]00MC only */
#define _CACHE_CACHABLE_COHERENT    (5<<_CACHE_SHIFT)  /* MIPS32R2 CMP    */
#define _CACHE_CACHABLE_CUW         (6<<_CACHE_SHIFT)  /* R4[04]00MC only */
#define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT)  /* R10000 only     */

#endif

#define __READABLE	(_PAGE_READ | _PAGE_SILENT_READ | _PAGE_ACCESSED)
#define __WRITEABLE	(_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED)

#define _PAGE_CHG_MASK  (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK)

#define CONF_CM_DEFAULT		(PAGE_CACHABLE_DEFAULT>>_CACHE_SHIFT)

#endif /* _ASM_PGTABLE_BITS_H */