2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * Copyright (C) 1994 - 2002 by Ralf Baechle
7 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
8 * Copyright (C) 2002 Maciej W. Rozycki
10 #ifndef _ASM_PGTABLE_BITS_H
11 #define _ASM_PGTABLE_BITS_H
15 * Note that we shift the lower 32bits of each EntryLo[01] entry
16 * 6 bits to the left. That way we can convert the PFN into the
17 * physical address by a single 'and' operation and gain 6 additional
18 * bits for storing information which isn't present in a normal
21 * Similar to the Alpha port, we need to keep track of the ref
22 * and mod bits in software. We have a software "yeah you can read
23 * from this page" bit, and a hardware one which actually lets the
24 * process read from the page. On the same token we have a software
25 * writable bit and the real hardware one which actually lets the
26 * process write to the page, this keeps a mod bit via the hardware
29 * Certain revisions of the R4000 and R5000 have a bug where if a
30 * certain sequence occurs in the last 3 instructions of an executable
31 * page, and the following page is not mapped, the cpu can do
32 * unpredictable things. The code (when it is written) to deal with
33 * this problem will be in the update_mmu_cache() code for the r4k.
35 #if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
37 #define _PAGE_PRESENT (1<<6) /* implemented in software */
38 #define _PAGE_READ (1<<7) /* implemented in software */
39 #define _PAGE_WRITE (1<<8) /* implemented in software */
40 #define _PAGE_ACCESSED (1<<9) /* implemented in software */
41 #define _PAGE_MODIFIED (1<<10) /* implemented in software */
42 #define _PAGE_FILE (1<<10) /* set:pagecache unset:swap */
44 #define _PAGE_R4KBUG (1<<0) /* workaround for r4k bug */
45 #define _PAGE_GLOBAL (1<<0)
46 #define _PAGE_VALID (1<<1)
47 #define _PAGE_SILENT_READ (1<<1) /* synonym */
48 #define _PAGE_DIRTY (1<<2) /* The MIPS dirty bit */
49 #define _PAGE_SILENT_WRITE (1<<2)
50 #define _CACHE_SHIFT 3
51 #define _CACHE_MASK (7<<3)
55 #define _PAGE_PRESENT (1<<0) /* implemented in software */
56 #define _PAGE_READ (1<<1) /* implemented in software */
57 #define _PAGE_WRITE (1<<2) /* implemented in software */
58 #define _PAGE_ACCESSED (1<<3) /* implemented in software */
59 #define _PAGE_MODIFIED (1<<4) /* implemented in software */
60 #define _PAGE_FILE (1<<4) /* set:pagecache unset:swap */
62 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
64 #define _PAGE_GLOBAL (1<<8)
65 #define _PAGE_VALID (1<<9)
66 #define _PAGE_SILENT_READ (1<<9) /* synonym */
67 #define _PAGE_DIRTY (1<<10) /* The MIPS dirty bit */
68 #define _PAGE_SILENT_WRITE (1<<10)
69 #define _CACHE_UNCACHED (1<<11)
70 #define _CACHE_MASK (1<<11)
74 #define _PAGE_R4KBUG (1<<5) /* workaround for r4k bug */
75 #define _PAGE_GLOBAL (1<<6)
76 #define _PAGE_VALID (1<<7)
77 #define _PAGE_SILENT_READ (1<<7) /* synonym */
78 #define _PAGE_DIRTY (1<<8) /* The MIPS dirty bit */
79 #define _PAGE_SILENT_WRITE (1<<8)
80 #define _CACHE_SHIFT 9
81 #define _CACHE_MASK (7<<9)
84 #endif /* defined(CONFIG_64BIT_PHYS_ADDR && defined(CONFIG_CPU_MIPS32) */
90 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
92 #define _CACHE_CACHABLE_NONCOHERENT 0
94 #elif defined(CONFIG_CPU_SB1)
96 /* No penalty for being coherent on the SB1, so just
97 use it for "noncoherent" spaces, too. Shouldn't hurt. */
99 #define _CACHE_UNCACHED (2<<_CACHE_SHIFT)
100 #define _CACHE_CACHABLE_COW (5<<_CACHE_SHIFT)
101 #define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
102 #define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT)
104 #elif defined(CONFIG_CPU_RM9000)
106 #define _CACHE_WT (0<<_CACHE_SHIFT)
107 #define _CACHE_WTWA (1<<_CACHE_SHIFT)
108 #define _CACHE_UC_B (2<<_CACHE_SHIFT)
109 #define _CACHE_WB (3<<_CACHE_SHIFT)
110 #define _CACHE_CWBEA (4<<_CACHE_SHIFT)
111 #define _CACHE_CWB (5<<_CACHE_SHIFT)
112 #define _CACHE_UCNB (6<<_CACHE_SHIFT)
113 #define _CACHE_FPC (7<<_CACHE_SHIFT)
115 #define _CACHE_UNCACHED _CACHE_UC_B
116 #define _CACHE_CACHABLE_NONCOHERENT _CACHE_WB
120 #define _CACHE_CACHABLE_NO_WA (0<<_CACHE_SHIFT) /* R4600 only */
121 #define _CACHE_CACHABLE_WA (1<<_CACHE_SHIFT) /* R4600 only */
122 #define _CACHE_UNCACHED (2<<_CACHE_SHIFT) /* R4[0246]00 */
123 #define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* R4[0246]00 */
124 #define _CACHE_CACHABLE_CE (4<<_CACHE_SHIFT) /* R4[04]00MC only */
125 #define _CACHE_CACHABLE_COW (5<<_CACHE_SHIFT) /* R4[04]00MC only */
126 #define _CACHE_CACHABLE_COHERENT (5<<_CACHE_SHIFT) /* MIPS32R2 CMP */
127 #define _CACHE_CACHABLE_CUW (6<<_CACHE_SHIFT) /* R4[04]00MC only */
128 #define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT) /* R10000 only */
132 #define __READABLE (_PAGE_READ | _PAGE_SILENT_READ | _PAGE_ACCESSED)
133 #define __WRITEABLE (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED)
135 #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK)
137 #endif /* _ASM_PGTABLE_BITS_H */