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1/*
2 *  linux/arch/arm/mm/cache-v4wb.S
3 *
4 *  Copyright (C) 1997-2002 Russell king
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <linux/linkage.h>
11#include <linux/init.h>
12#include <asm/assembler.h>
13#include <asm/memory.h>
14#include <asm/page.h>
15#include "proc-macros.S"
16
17/*
18 * The size of one data cache line.
19 */
20#define CACHE_DLINESIZE	32
21
22/*
23 * The total size of the data cache.
24 */
25#if defined(CONFIG_CPU_SA110)
26# define CACHE_DSIZE	16384
27#elif defined(CONFIG_CPU_SA1100)
28# define CACHE_DSIZE	8192
29#else
30# error Unknown cache size
31#endif
32
33/*
34 * This is the size at which it becomes more efficient to
35 * clean the whole cache, rather than using the individual
36 * cache line maintenance instructions.
37 *
38 *  Size  Clean (ticks) Dirty (ticks)
39 *   4096   21  20  21    53  55  54
40 *   8192   40  41  40   106 100 102
41 *  16384   77  77  76   140 140 138
42 *  32768  150 149 150   214 216 212 <---
43 *  65536  296 297 296   351 358 361
44 * 131072  591 591 591   656 657 651
45 *  Whole  132 136 132   221 217 207 <---
46 */
47#define CACHE_DLIMIT	(CACHE_DSIZE * 4)
48
49	.data
50flush_base:
51	.long	FLUSH_BASE
52	.text
53
54/*
55 *	flush_icache_all()
56 *
57 *	Unconditionally clean and invalidate the entire icache.
58 */
59ENTRY(v4wb_flush_icache_all)
60	mov	r0, #0
61	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
62	ret	lr
63ENDPROC(v4wb_flush_icache_all)
64
65/*
66 *	flush_user_cache_all()
67 *
68 *	Clean and invalidate all cache entries in a particular address
69 *	space.
70 */
71ENTRY(v4wb_flush_user_cache_all)
72	/* FALLTHROUGH */
73/*
74 *	flush_kern_cache_all()
75 *
76 *	Clean and invalidate the entire cache.
77 */
78ENTRY(v4wb_flush_kern_cache_all)
79	mov	ip, #0
80	mcr	p15, 0, ip, c7, c5, 0		@ invalidate I cache
81__flush_whole_cache:
82	ldr	r3, =flush_base
83	ldr	r1, [r3, #0]
84	eor	r1, r1, #CACHE_DSIZE
85	str	r1, [r3, #0]
86	add	r2, r1, #CACHE_DSIZE
871:	ldr	r3, [r1], #32
88	cmp	r1, r2
89	blo	1b
90#ifdef FLUSH_BASE_MINICACHE
91	add	r2, r2, #FLUSH_BASE_MINICACHE - FLUSH_BASE
92	sub	r1, r2, #512			@ only 512 bytes
931:	ldr	r3, [r1], #32
94	cmp	r1, r2
95	blo	1b
96#endif
97	mcr	p15, 0, ip, c7, c10, 4		@ drain write buffer
98	ret	lr
99
100/*
101 *	flush_user_cache_range(start, end, flags)
102 *
103 *	Invalidate a range of cache entries in the specified
104 *	address space.
105 *
106 *	- start - start address (inclusive, page aligned)
107 *	- end	- end address (exclusive, page aligned)
108 *	- flags	- vma_area_struct flags describing address space
109 */
110ENTRY(v4wb_flush_user_cache_range)
111	mov	ip, #0
112	sub	r3, r1, r0			@ calculate total size
113	tst	r2, #VM_EXEC			@ executable region?
114	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
115
116	cmp	r3, #CACHE_DLIMIT		@ total size >= limit?
117	bhs	__flush_whole_cache		@ flush whole D cache
118
1191:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
120	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
121	add	r0, r0, #CACHE_DLINESIZE
122	cmp	r0, r1
123	blo	1b
124	tst	r2, #VM_EXEC
125	mcrne	p15, 0, ip, c7, c10, 4		@ drain write buffer
126	ret	lr
127
128/*
129 *	flush_kern_dcache_area(void *addr, size_t size)
130 *
131 *	Ensure no D cache aliasing occurs, either with itself or
132 *	the I cache
133 *
134 *	- addr	- kernel address
135 *	- size	- region size
136 */
137ENTRY(v4wb_flush_kern_dcache_area)
138	add	r1, r0, r1
139	/* fall through */
140
141/*
142 *	coherent_kern_range(start, end)
143 *
144 *	Ensure coherency between the Icache and the Dcache in the
145 *	region described by start.  If you have non-snooping
146 *	Harvard caches, you need to implement this function.
147 *
148 *	- start  - virtual start address
149 *	- end	 - virtual end address
150 */
151ENTRY(v4wb_coherent_kern_range)
152	/* fall through */
153
154/*
155 *	coherent_user_range(start, end)
156 *
157 *	Ensure coherency between the Icache and the Dcache in the
158 *	region described by start.  If you have non-snooping
159 *	Harvard caches, you need to implement this function.
160 *
161 *	- start  - virtual start address
162 *	- end	 - virtual end address
163 */
164ENTRY(v4wb_coherent_user_range)
165	bic	r0, r0, #CACHE_DLINESIZE - 1
1661:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
167	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
168	add	r0, r0, #CACHE_DLINESIZE
169	cmp	r0, r1
170	blo	1b
171	mov	r0, #0
172	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
173	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
174	ret	lr
175
176
177/*
178 *	dma_inv_range(start, end)
179 *
180 *	Invalidate (discard) the specified virtual address range.
181 *	May not write back any entries.  If 'start' or 'end'
182 *	are not cache line aligned, those lines must be written
183 *	back.
184 *
185 *	- start  - virtual start address
186 *	- end	 - virtual end address
187 */
188v4wb_dma_inv_range:
189	tst	r0, #CACHE_DLINESIZE - 1
190	bic	r0, r0, #CACHE_DLINESIZE - 1
191	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
192	tst	r1, #CACHE_DLINESIZE - 1
193	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
1941:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
195	add	r0, r0, #CACHE_DLINESIZE
196	cmp	r0, r1
197	blo	1b
198	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
199	ret	lr
200
201/*
202 *	dma_clean_range(start, end)
203 *
204 *	Clean (write back) the specified virtual address range.
205 *
206 *	- start  - virtual start address
207 *	- end	 - virtual end address
208 */
209v4wb_dma_clean_range:
210	bic	r0, r0, #CACHE_DLINESIZE - 1
2111:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
212	add	r0, r0, #CACHE_DLINESIZE
213	cmp	r0, r1
214	blo	1b
215	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
216	ret	lr
217
218/*
219 *	dma_flush_range(start, end)
220 *
221 *	Clean and invalidate the specified virtual address range.
222 *
223 *	- start  - virtual start address
224 *	- end	 - virtual end address
225 *
226 *	This is actually the same as v4wb_coherent_kern_range()
227 */
228	.globl	v4wb_dma_flush_range
229	.set	v4wb_dma_flush_range, v4wb_coherent_kern_range
230
231/*
232 *	dma_map_area(start, size, dir)
233 *	- start	- kernel virtual start address
234 *	- size	- size of region
235 *	- dir	- DMA direction
236 */
237ENTRY(v4wb_dma_map_area)
238	add	r1, r1, r0
239	cmp	r2, #DMA_TO_DEVICE
240	beq	v4wb_dma_clean_range
241	bcs	v4wb_dma_inv_range
242	b	v4wb_dma_flush_range
243ENDPROC(v4wb_dma_map_area)
244
245/*
246 *	dma_unmap_area(start, size, dir)
247 *	- start	- kernel virtual start address
248 *	- size	- size of region
249 *	- dir	- DMA direction
250 */
251ENTRY(v4wb_dma_unmap_area)
252	ret	lr
253ENDPROC(v4wb_dma_unmap_area)
254
255	.globl	v4wb_flush_kern_cache_louis
256	.equ	v4wb_flush_kern_cache_louis, v4wb_flush_kern_cache_all
257
258	__INITDATA
259
260	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
261	define_cache_functions v4wb
262