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_PHYS_ADDR_T_64BIT) && defined(CONFIG_CPU_MIPS32)
38 * The following bits are directly used by the TLB hardware
40 #define _PAGE_GLOBAL_SHIFT 0
41 #define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT)
42 #define _PAGE_VALID_SHIFT (_PAGE_GLOBAL_SHIFT + 1)
43 #define _PAGE_VALID (1 << _PAGE_VALID_SHIFT)
44 #define _PAGE_DIRTY_SHIFT (_PAGE_VALID_SHIFT + 1)
45 #define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
46 #define _CACHE_SHIFT (_PAGE_DIRTY_SHIFT + 1)
47 #define _CACHE_MASK (7 << _CACHE_SHIFT)
50 * The following bits are implemented in software
52 #define _PAGE_PRESENT_SHIFT (_CACHE_SHIFT + 3)
53 #define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
54 #define _PAGE_READ_SHIFT (_PAGE_PRESENT_SHIFT + 1)
55 #define _PAGE_READ (1 << _PAGE_READ_SHIFT)
56 #define _PAGE_WRITE_SHIFT (_PAGE_READ_SHIFT + 1)
57 #define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
58 #define _PAGE_ACCESSED_SHIFT (_PAGE_WRITE_SHIFT + 1)
59 #define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
60 #define _PAGE_MODIFIED_SHIFT (_PAGE_ACCESSED_SHIFT + 1)
61 #define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
63 #define _PAGE_SILENT_READ _PAGE_VALID
64 #define _PAGE_SILENT_WRITE _PAGE_DIRTY
66 #define _PFN_SHIFT (PAGE_SHIFT - 12 + _CACHE_SHIFT + 3)
68 #elif defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
71 * The following are implemented by software
73 #define _PAGE_PRESENT_SHIFT 0
74 #define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
75 #define _PAGE_READ_SHIFT 1
76 #define _PAGE_READ (1 << _PAGE_READ_SHIFT)
77 #define _PAGE_WRITE_SHIFT 2
78 #define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
79 #define _PAGE_ACCESSED_SHIFT 3
80 #define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
81 #define _PAGE_MODIFIED_SHIFT 4
82 #define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
85 * And these are the hardware TLB bits
87 #define _PAGE_GLOBAL_SHIFT 8
88 #define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT)
89 #define _PAGE_VALID_SHIFT 9
90 #define _PAGE_VALID (1 << _PAGE_VALID_SHIFT)
91 #define _PAGE_SILENT_READ (1 << _PAGE_VALID_SHIFT) /* synonym */
92 #define _PAGE_DIRTY_SHIFT 10
93 #define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
94 #define _PAGE_SILENT_WRITE (1 << _PAGE_DIRTY_SHIFT)
95 #define _CACHE_UNCACHED_SHIFT 11
96 #define _CACHE_UNCACHED (1 << _CACHE_UNCACHED_SHIFT)
97 #define _CACHE_MASK (1 << _CACHE_UNCACHED_SHIFT)
99 #else /* 'Normal' r4K case */
101 * When using the RI/XI bit support, we have 13 bits of flags below
102 * the physical address. The RI/XI bits are placed such that a SRL 5
103 * can strip off the software bits, then a ROTR 2 can move the RI/XI
104 * into bits [63:62]. This also limits physical address to 56 bits,
105 * which is more than we need right now.
109 * The following bits are implemented in software
111 * _PAGE_READ / _PAGE_READ_SHIFT should be unused if cpu_has_rixi.
113 #define _PAGE_PRESENT_SHIFT (0)
114 #define _PAGE_PRESENT (1 << _PAGE_PRESENT_SHIFT)
115 #define _PAGE_READ_SHIFT (cpu_has_rixi ? _PAGE_PRESENT_SHIFT : _PAGE_PRESENT_SHIFT + 1)
116 #define _PAGE_READ ({BUG_ON(cpu_has_rixi); 1 << _PAGE_READ_SHIFT; })
117 #define _PAGE_WRITE_SHIFT (_PAGE_READ_SHIFT + 1)
118 #define _PAGE_WRITE (1 << _PAGE_WRITE_SHIFT)
119 #define _PAGE_ACCESSED_SHIFT (_PAGE_WRITE_SHIFT + 1)
120 #define _PAGE_ACCESSED (1 << _PAGE_ACCESSED_SHIFT)
121 #define _PAGE_MODIFIED_SHIFT (_PAGE_ACCESSED_SHIFT + 1)
122 #define _PAGE_MODIFIED (1 << _PAGE_MODIFIED_SHIFT)
124 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
126 #define _PAGE_HUGE_SHIFT (_PAGE_MODIFIED_SHIFT + 1)
127 #define _PAGE_HUGE (1 << _PAGE_HUGE_SHIFT)
129 #define _PAGE_HUGE_SHIFT (_PAGE_MODIFIED_SHIFT)
130 #define _PAGE_HUGE ({BUG(); 1; }) /* Dummy value */
133 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
135 #define _PAGE_SPLITTING_SHIFT (_PAGE_HUGE_SHIFT + 1)
136 #define _PAGE_SPLITTING (1 << _PAGE_SPLITTING_SHIFT)
138 #define _PAGE_SPLITTING_SHIFT (_PAGE_HUGE_SHIFT)
139 #define _PAGE_SPLITTING ({BUG(); 1; }) /* Dummy value */
142 /* Page cannot be executed */
143 #define _PAGE_NO_EXEC_SHIFT (cpu_has_rixi ? _PAGE_SPLITTING_SHIFT + 1 : _PAGE_SPLITTING_SHIFT)
144 #define _PAGE_NO_EXEC ({BUG_ON(!cpu_has_rixi); 1 << _PAGE_NO_EXEC_SHIFT; })
146 /* Page cannot be read */
147 #define _PAGE_NO_READ_SHIFT (cpu_has_rixi ? _PAGE_NO_EXEC_SHIFT + 1 : _PAGE_NO_EXEC_SHIFT)
148 #define _PAGE_NO_READ ({BUG_ON(!cpu_has_rixi); 1 << _PAGE_NO_READ_SHIFT; })
150 #define _PAGE_GLOBAL_SHIFT (_PAGE_NO_READ_SHIFT + 1)
151 #define _PAGE_GLOBAL (1 << _PAGE_GLOBAL_SHIFT)
153 #define _PAGE_VALID_SHIFT (_PAGE_GLOBAL_SHIFT + 1)
154 #define _PAGE_VALID (1 << _PAGE_VALID_SHIFT)
156 #define _PAGE_SILENT_READ (_PAGE_VALID)
158 /* The MIPS dirty bit */
159 #define _PAGE_DIRTY_SHIFT (_PAGE_VALID_SHIFT + 1)
160 #define _PAGE_DIRTY (1 << _PAGE_DIRTY_SHIFT)
161 #define _PAGE_SILENT_WRITE (_PAGE_DIRTY)
163 #define _CACHE_SHIFT (_PAGE_DIRTY_SHIFT + 1)
164 #define _CACHE_MASK (7 << _CACHE_SHIFT)
166 #define _PFN_SHIFT (PAGE_SHIFT - 12 + _CACHE_SHIFT + 3)
168 #endif /* defined(CONFIG_PHYS_ADDR_T_64BIT && defined(CONFIG_CPU_MIPS32) */
171 #define _PFN_SHIFT PAGE_SHIFT
173 #define _PFN_MASK (~((1 << (_PFN_SHIFT)) - 1))
175 #ifndef _PAGE_NO_READ
176 #define _PAGE_NO_READ ({BUG(); 0; })
177 #define _PAGE_NO_READ_SHIFT ({BUG(); 0; })
179 #ifndef _PAGE_NO_EXEC
180 #define _PAGE_NO_EXEC ({BUG(); 0; })
182 #ifndef _PAGE_GLOBAL_SHIFT
183 #define _PAGE_GLOBAL_SHIFT ilog2(_PAGE_GLOBAL)
189 * pte_to_entrylo converts a page table entry (PTE) into a Mips
192 static inline uint64_t pte_to_entrylo(unsigned long pte_val)
197 sa = 31 - _PAGE_NO_READ_SHIFT;
199 sa = 63 - _PAGE_NO_READ_SHIFT;
202 * C has no way to express that this is a DSRL
203 * _PAGE_NO_EXEC_SHIFT followed by a ROTR 2. Luckily
204 * in the fast path this is done in assembly
206 return (pte_val >> _PAGE_GLOBAL_SHIFT) |
207 ((pte_val & (_PAGE_NO_EXEC | _PAGE_NO_READ)) << sa);
210 return pte_val >> _PAGE_GLOBAL_SHIFT;
217 #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
219 #define _CACHE_CACHABLE_NONCOHERENT 0
220 #define _CACHE_UNCACHED_ACCELERATED _CACHE_UNCACHED
222 #elif defined(CONFIG_CPU_SB1)
224 /* No penalty for being coherent on the SB1, so just
225 use it for "noncoherent" spaces, too. Shouldn't hurt. */
227 #define _CACHE_CACHABLE_NONCOHERENT (5<<_CACHE_SHIFT)
229 #elif defined(CONFIG_CPU_LOONGSON3)
231 /* Using COHERENT flag for NONCOHERENT doesn't hurt. */
233 #define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT) /* LOONGSON */
234 #define _CACHE_CACHABLE_COHERENT (3<<_CACHE_SHIFT) /* LOONGSON-3 */
236 #elif defined(CONFIG_MACH_JZ4740)
238 /* Ingenic uses the WA bit to achieve write-combine memory writes */
239 #define _CACHE_UNCACHED_ACCELERATED (1<<_CACHE_SHIFT)
243 #ifndef _CACHE_CACHABLE_NO_WA
244 #define _CACHE_CACHABLE_NO_WA (0<<_CACHE_SHIFT)
246 #ifndef _CACHE_CACHABLE_WA
247 #define _CACHE_CACHABLE_WA (1<<_CACHE_SHIFT)
249 #ifndef _CACHE_UNCACHED
250 #define _CACHE_UNCACHED (2<<_CACHE_SHIFT)
252 #ifndef _CACHE_CACHABLE_NONCOHERENT
253 #define _CACHE_CACHABLE_NONCOHERENT (3<<_CACHE_SHIFT)
255 #ifndef _CACHE_CACHABLE_CE
256 #define _CACHE_CACHABLE_CE (4<<_CACHE_SHIFT)
258 #ifndef _CACHE_CACHABLE_COW
259 #define _CACHE_CACHABLE_COW (5<<_CACHE_SHIFT)
261 #ifndef _CACHE_CACHABLE_CUW
262 #define _CACHE_CACHABLE_CUW (6<<_CACHE_SHIFT)
264 #ifndef _CACHE_UNCACHED_ACCELERATED
265 #define _CACHE_UNCACHED_ACCELERATED (7<<_CACHE_SHIFT)
268 #define __READABLE (_PAGE_SILENT_READ | _PAGE_ACCESSED | (cpu_has_rixi ? 0 : _PAGE_READ))
269 #define __WRITEABLE (_PAGE_WRITE | _PAGE_SILENT_WRITE | _PAGE_MODIFIED)
271 #define _PAGE_CHG_MASK (_PFN_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK)
273 #endif /* _ASM_PGTABLE_BITS_H */