xref: /openbmc/linux/arch/arm/mm/cache-v4wb.S (revision 95e9fd10)
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/memory.h>
13#include <asm/page.h>
14#include "proc-macros.S"
15
16/*
17 * The size of one data cache line.
18 */
19#define CACHE_DLINESIZE	32
20
21/*
22 * The total size of the data cache.
23 */
24#if defined(CONFIG_CPU_SA110)
25# define CACHE_DSIZE	16384
26#elif defined(CONFIG_CPU_SA1100)
27# define CACHE_DSIZE	8192
28#else
29# error Unknown cache size
30#endif
31
32/*
33 * This is the size at which it becomes more efficient to
34 * clean the whole cache, rather than using the individual
35 * cache line maintenance instructions.
36 *
37 *  Size  Clean (ticks) Dirty (ticks)
38 *   4096   21  20  21    53  55  54
39 *   8192   40  41  40   106 100 102
40 *  16384   77  77  76   140 140 138
41 *  32768  150 149 150   214 216 212 <---
42 *  65536  296 297 296   351 358 361
43 * 131072  591 591 591   656 657 651
44 *  Whole  132 136 132   221 217 207 <---
45 */
46#define CACHE_DLIMIT	(CACHE_DSIZE * 4)
47
48	.data
49flush_base:
50	.long	FLUSH_BASE
51	.text
52
53/*
54 *	flush_icache_all()
55 *
56 *	Unconditionally clean and invalidate the entire icache.
57 */
58ENTRY(v4wb_flush_icache_all)
59	mov	r0, #0
60	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
61	mov	pc, lr
62ENDPROC(v4wb_flush_icache_all)
63
64/*
65 *	flush_user_cache_all()
66 *
67 *	Clean and invalidate all cache entries in a particular address
68 *	space.
69 */
70ENTRY(v4wb_flush_user_cache_all)
71	/* FALLTHROUGH */
72/*
73 *	flush_kern_cache_all()
74 *
75 *	Clean and invalidate the entire cache.
76 */
77ENTRY(v4wb_flush_kern_cache_all)
78	mov	ip, #0
79	mcr	p15, 0, ip, c7, c5, 0		@ invalidate I cache
80__flush_whole_cache:
81	ldr	r3, =flush_base
82	ldr	r1, [r3, #0]
83	eor	r1, r1, #CACHE_DSIZE
84	str	r1, [r3, #0]
85	add	r2, r1, #CACHE_DSIZE
861:	ldr	r3, [r1], #32
87	cmp	r1, r2
88	blo	1b
89#ifdef FLUSH_BASE_MINICACHE
90	add	r2, r2, #FLUSH_BASE_MINICACHE - FLUSH_BASE
91	sub	r1, r2, #512			@ only 512 bytes
921:	ldr	r3, [r1], #32
93	cmp	r1, r2
94	blo	1b
95#endif
96	mcr	p15, 0, ip, c7, c10, 4		@ drain write buffer
97	mov	pc, lr
98
99/*
100 *	flush_user_cache_range(start, end, flags)
101 *
102 *	Invalidate a range of cache entries in the specified
103 *	address space.
104 *
105 *	- start - start address (inclusive, page aligned)
106 *	- end	- end address (exclusive, page aligned)
107 *	- flags	- vma_area_struct flags describing address space
108 */
109ENTRY(v4wb_flush_user_cache_range)
110	mov	ip, #0
111	sub	r3, r1, r0			@ calculate total size
112	tst	r2, #VM_EXEC			@ executable region?
113	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
114
115	cmp	r3, #CACHE_DLIMIT		@ total size >= limit?
116	bhs	__flush_whole_cache		@ flush whole D cache
117
1181:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
119	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
120	add	r0, r0, #CACHE_DLINESIZE
121	cmp	r0, r1
122	blo	1b
123	tst	r2, #VM_EXEC
124	mcrne	p15, 0, ip, c7, c10, 4		@ drain write buffer
125	mov	pc, lr
126
127/*
128 *	flush_kern_dcache_area(void *addr, size_t size)
129 *
130 *	Ensure no D cache aliasing occurs, either with itself or
131 *	the I cache
132 *
133 *	- addr	- kernel address
134 *	- size	- region size
135 */
136ENTRY(v4wb_flush_kern_dcache_area)
137	add	r1, r0, r1
138	/* fall through */
139
140/*
141 *	coherent_kern_range(start, end)
142 *
143 *	Ensure coherency between the Icache and the Dcache in the
144 *	region described by start.  If you have non-snooping
145 *	Harvard caches, you need to implement this function.
146 *
147 *	- start  - virtual start address
148 *	- end	 - virtual end address
149 */
150ENTRY(v4wb_coherent_kern_range)
151	/* fall through */
152
153/*
154 *	coherent_user_range(start, end)
155 *
156 *	Ensure coherency between the Icache and the Dcache in the
157 *	region described by start.  If you have non-snooping
158 *	Harvard caches, you need to implement this function.
159 *
160 *	- start  - virtual start address
161 *	- end	 - virtual end address
162 */
163ENTRY(v4wb_coherent_user_range)
164	bic	r0, r0, #CACHE_DLINESIZE - 1
1651:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
166	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
167	add	r0, r0, #CACHE_DLINESIZE
168	cmp	r0, r1
169	blo	1b
170	mov	r0, #0
171	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
172	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
173	mov	pc, lr
174
175
176/*
177 *	dma_inv_range(start, end)
178 *
179 *	Invalidate (discard) the specified virtual address range.
180 *	May not write back any entries.  If 'start' or 'end'
181 *	are not cache line aligned, those lines must be written
182 *	back.
183 *
184 *	- start  - virtual start address
185 *	- end	 - virtual end address
186 */
187v4wb_dma_inv_range:
188	tst	r0, #CACHE_DLINESIZE - 1
189	bic	r0, r0, #CACHE_DLINESIZE - 1
190	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
191	tst	r1, #CACHE_DLINESIZE - 1
192	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
1931:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
194	add	r0, r0, #CACHE_DLINESIZE
195	cmp	r0, r1
196	blo	1b
197	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
198	mov	pc, lr
199
200/*
201 *	dma_clean_range(start, end)
202 *
203 *	Clean (write back) the specified virtual address range.
204 *
205 *	- start  - virtual start address
206 *	- end	 - virtual end address
207 */
208v4wb_dma_clean_range:
209	bic	r0, r0, #CACHE_DLINESIZE - 1
2101:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
211	add	r0, r0, #CACHE_DLINESIZE
212	cmp	r0, r1
213	blo	1b
214	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
215	mov	pc, lr
216
217/*
218 *	dma_flush_range(start, end)
219 *
220 *	Clean and invalidate the specified virtual address range.
221 *
222 *	- start  - virtual start address
223 *	- end	 - virtual end address
224 *
225 *	This is actually the same as v4wb_coherent_kern_range()
226 */
227	.globl	v4wb_dma_flush_range
228	.set	v4wb_dma_flush_range, v4wb_coherent_kern_range
229
230/*
231 *	dma_map_area(start, size, dir)
232 *	- start	- kernel virtual start address
233 *	- size	- size of region
234 *	- dir	- DMA direction
235 */
236ENTRY(v4wb_dma_map_area)
237	add	r1, r1, r0
238	cmp	r2, #DMA_TO_DEVICE
239	beq	v4wb_dma_clean_range
240	bcs	v4wb_dma_inv_range
241	b	v4wb_dma_flush_range
242ENDPROC(v4wb_dma_map_area)
243
244/*
245 *	dma_unmap_area(start, size, dir)
246 *	- start	- kernel virtual start address
247 *	- size	- size of region
248 *	- dir	- DMA direction
249 */
250ENTRY(v4wb_dma_unmap_area)
251	mov	pc, lr
252ENDPROC(v4wb_dma_unmap_area)
253
254	__INITDATA
255
256	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
257	define_cache_functions v4wb
258