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
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
/*
* linux/arch/arm/mm/cache-v4wt.S
*
* Copyright (C) 1997-2002 Russell king
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* ARMv4 write through cache operations support.
*
* We assume that the write buffer is not enabled.
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/page.h>
#include "proc-macros.S"
/*
* The size of one data cache line.
*/
#define CACHE_DLINESIZE 32
/*
* The number of data cache segments.
*/
#define CACHE_DSEGMENTS 8
/*
* The number of lines in a cache segment.
*/
#define CACHE_DENTRIES 64
/*
* This is the size at which it becomes more efficient to
* clean the whole cache, rather than using the individual
* cache line maintainence instructions.
*
* *** This needs benchmarking
*/
#define CACHE_DLIMIT 16384
/*
* flush_user_cache_all()
*
* Invalidate all cache entries in a particular address
* space.
*/
ENTRY(v4wt_flush_user_cache_all)
/* FALLTHROUGH */
/*
* flush_kern_cache_all()
*
* Clean and invalidate the entire cache.
*/
ENTRY(v4wt_flush_kern_cache_all)
mov r2, #VM_EXEC
mov ip, #0
__flush_whole_cache:
tst r2, #VM_EXEC
mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
mov pc, lr
/*
* flush_user_cache_range(start, end, flags)
*
* Clean and invalidate a range of cache entries in the specified
* address space.
*
* - start - start address (inclusive, page aligned)
* - end - end address (exclusive, page aligned)
* - flags - vma_area_struct flags describing address space
*/
ENTRY(v4wt_flush_user_cache_range)
sub r3, r1, r0 @ calculate total size
cmp r3, #CACHE_DLIMIT
bhs __flush_whole_cache
1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
tst r2, #VM_EXEC
mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
add r0, r0, #CACHE_DLINESIZE
cmp r0, r1
blo 1b
mov pc, lr
/*
* coherent_kern_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start. If you have non-snooping
* Harvard caches, you need to implement this function.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(v4wt_coherent_kern_range)
/* FALLTRHOUGH */
/*
* coherent_user_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start. If you have non-snooping
* Harvard caches, you need to implement this function.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(v4wt_coherent_user_range)
bic r0, r0, #CACHE_DLINESIZE - 1
1: mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
add r0, r0, #CACHE_DLINESIZE
cmp r0, r1
blo 1b
mov pc, lr
/*
* flush_kern_dcache_area(void *addr, size_t size)
*
* Ensure no D cache aliasing occurs, either with itself or
* the I cache
*
* - addr - kernel address
* - size - region size
*/
ENTRY(v4wt_flush_kern_dcache_area)
mov r2, #0
mcr p15, 0, r2, c7, c5, 0 @ invalidate I cache
add r1, r0, r1
/* fallthrough */
/*
* dma_inv_range(start, end)
*
* Invalidate (discard) the specified virtual address range.
* May not write back any entries. If 'start' or 'end'
* are not cache line aligned, those lines must be written
* back.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(v4wt_dma_inv_range)
bic r0, r0, #CACHE_DLINESIZE - 1
1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
add r0, r0, #CACHE_DLINESIZE
cmp r0, r1
blo 1b
/* FALLTHROUGH */
/*
* dma_clean_range(start, end)
*
* Clean the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
ENTRY(v4wt_dma_clean_range)
mov pc, lr
/*
* dma_flush_range(start, end)
*
* Clean and invalidate the specified virtual address range.
*
* - start - virtual start address
* - end - virtual end address
*/
.globl v4wt_dma_flush_range
.equ v4wt_dma_flush_range, v4wt_dma_inv_range
/*
* dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(v4wt_dma_unmap_area)
add r1, r1, r0
teq r2, #DMA_TO_DEVICE
bne v4wt_dma_inv_range
/* FALLTHROUGH */
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(v4wt_dma_map_area)
mov pc, lr
ENDPROC(v4wt_dma_unmap_area)
ENDPROC(v4wt_dma_map_area)
__INITDATA
.type v4wt_cache_fns, #object
ENTRY(v4wt_cache_fns)
.long v4wt_flush_kern_cache_all
.long v4wt_flush_user_cache_all
.long v4wt_flush_user_cache_range
.long v4wt_coherent_kern_range
.long v4wt_coherent_user_range
.long v4wt_flush_kern_dcache_area
.long v4wt_dma_map_area
.long v4wt_dma_unmap_area
.long v4wt_dma_inv_range
.long v4wt_dma_clean_range
.long v4wt_dma_flush_range
.size v4wt_cache_fns, . - v4wt_cache_fns
|
