xref: /openbmc/linux/arch/arm/mm/cache-fa.S (revision 829c6524)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *  linux/arch/arm/mm/cache-fa.S
4 *
5 *  Copyright (C) 2005 Faraday Corp.
6 *  Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
7 *
8 * Based on cache-v4wb.S:
9 *  Copyright (C) 1997-2002 Russell king
10 *
11 *  Processors: FA520 FA526 FA626
12 */
13#include <linux/linkage.h>
14#include <linux/init.h>
15#include <asm/assembler.h>
16#include <asm/page.h>
17
18#include "proc-macros.S"
19
20/*
21 * The size of one data cache line.
22 */
23#define CACHE_DLINESIZE	16
24
25/*
26 * The total size of the data cache.
27 */
28#ifdef CONFIG_ARCH_GEMINI
29#define CACHE_DSIZE	8192
30#else
31#define CACHE_DSIZE	16384
32#endif
33
34/* FIXME: put optimal value here. Current one is just estimation */
35#define CACHE_DLIMIT	(CACHE_DSIZE * 2)
36
37/*
38 *	flush_icache_all()
39 *
40 *	Unconditionally clean and invalidate the entire icache.
41 */
42ENTRY(fa_flush_icache_all)
43	mov	r0, #0
44	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
45	ret	lr
46ENDPROC(fa_flush_icache_all)
47
48/*
49 *	flush_user_cache_all()
50 *
51 *	Clean and invalidate all cache entries in a particular address
52 *	space.
53 */
54ENTRY(fa_flush_user_cache_all)
55	/* FALLTHROUGH */
56/*
57 *	flush_kern_cache_all()
58 *
59 *	Clean and invalidate the entire cache.
60 */
61ENTRY(fa_flush_kern_cache_all)
62	mov	ip, #0
63	mov	r2, #VM_EXEC
64__flush_whole_cache:
65	mcr	p15, 0, ip, c7, c14, 0		@ clean/invalidate D cache
66	tst	r2, #VM_EXEC
67	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
68	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
69	mcrne	p15, 0, ip, c7, c10, 4		@ drain write buffer
70	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
71	ret	lr
72
73/*
74 *	flush_user_cache_range(start, end, flags)
75 *
76 *	Invalidate a range of cache entries in the specified
77 *	address space.
78 *
79 *	- start - start address (inclusive, page aligned)
80 *	- end	- end address (exclusive, page aligned)
81 *	- flags	- vma_area_struct flags describing address space
82 */
83ENTRY(fa_flush_user_cache_range)
84	mov	ip, #0
85	sub	r3, r1, r0			@ calculate total size
86	cmp	r3, #CACHE_DLIMIT		@ total size >= limit?
87	bhs	__flush_whole_cache		@ flush whole D cache
88
891:	tst	r2, #VM_EXEC
90	mcrne	p15, 0, r0, c7, c5, 1		@ invalidate I line
91	mcr	p15, 0, r0, c7, c14, 1		@ clean and invalidate D entry
92	add	r0, r0, #CACHE_DLINESIZE
93	cmp	r0, r1
94	blo	1b
95	tst	r2, #VM_EXEC
96	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
97	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
98	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
99	ret	lr
100
101/*
102 *	coherent_kern_range(start, end)
103 *
104 *	Ensure coherency between the Icache and the Dcache in the
105 *	region described by start.  If you have non-snooping
106 *	Harvard caches, you need to implement this function.
107 *
108 *	- start  - virtual start address
109 *	- end	 - virtual end address
110 */
111ENTRY(fa_coherent_kern_range)
112	/* fall through */
113
114/*
115 *	coherent_user_range(start, end)
116 *
117 *	Ensure coherency between the Icache and the Dcache in the
118 *	region described by start.  If you have non-snooping
119 *	Harvard caches, you need to implement this function.
120 *
121 *	- start  - virtual start address
122 *	- end	 - virtual end address
123 */
124ENTRY(fa_coherent_user_range)
125	bic	r0, r0, #CACHE_DLINESIZE - 1
1261:	mcr	p15, 0, r0, c7, c14, 1		@ clean and invalidate D entry
127	mcr	p15, 0, r0, c7, c5, 1		@ invalidate I entry
128	add	r0, r0, #CACHE_DLINESIZE
129	cmp	r0, r1
130	blo	1b
131	mov	r0, #0
132	mcr	p15, 0, r0, c7, c5, 6		@ invalidate BTB
133	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
134	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
135	ret	lr
136
137/*
138 *	flush_kern_dcache_area(void *addr, size_t size)
139 *
140 *	Ensure that the data held in the page kaddr is written back
141 *	to the page in question.
142 *
143 *	- addr	- kernel address
144 *	- size	- size of region
145 */
146ENTRY(fa_flush_kern_dcache_area)
147	add	r1, r0, r1
1481:	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
149	add	r0, r0, #CACHE_DLINESIZE
150	cmp	r0, r1
151	blo	1b
152	mov	r0, #0
153	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
154	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
155	ret	lr
156
157/*
158 *	dma_inv_range(start, end)
159 *
160 *	Invalidate (discard) the specified virtual address range.
161 *	May not write back any entries.  If 'start' or 'end'
162 *	are not cache line aligned, those lines must be written
163 *	back.
164 *
165 *	- start  - virtual start address
166 *	- end	 - virtual end address
167 */
168fa_dma_inv_range:
169	tst	r0, #CACHE_DLINESIZE - 1
170	bic	r0, r0, #CACHE_DLINESIZE - 1
171	mcrne	p15, 0, r0, c7, c14, 1		@ clean & invalidate D entry
172	tst	r1, #CACHE_DLINESIZE - 1
173	bic	r1, r1, #CACHE_DLINESIZE - 1
174	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D entry
1751:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
176	add	r0, r0, #CACHE_DLINESIZE
177	cmp	r0, r1
178	blo	1b
179	mov	r0, #0
180	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
181	ret	lr
182
183/*
184 *	dma_clean_range(start, end)
185 *
186 *	Clean (write back) the specified virtual address range.
187 *
188 *	- start  - virtual start address
189 *	- end	 - virtual end address
190 */
191fa_dma_clean_range:
192	bic	r0, r0, #CACHE_DLINESIZE - 1
1931:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
194	add	r0, r0, #CACHE_DLINESIZE
195	cmp	r0, r1
196	blo	1b
197	mov	r0, #0
198	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
199	ret	lr
200
201/*
202 *	dma_flush_range(start,end)
203 *	- start   - virtual start address of region
204 *	- end     - virtual end address of region
205 */
206ENTRY(fa_dma_flush_range)
207	bic	r0, r0, #CACHE_DLINESIZE - 1
2081:	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D entry
209	add	r0, r0, #CACHE_DLINESIZE
210	cmp	r0, r1
211	blo	1b
212	mov	r0, #0
213	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
214	ret	lr
215
216/*
217 *	dma_map_area(start, size, dir)
218 *	- start	- kernel virtual start address
219 *	- size	- size of region
220 *	- dir	- DMA direction
221 */
222ENTRY(fa_dma_map_area)
223	add	r1, r1, r0
224	cmp	r2, #DMA_TO_DEVICE
225	beq	fa_dma_clean_range
226	bcs	fa_dma_inv_range
227	b	fa_dma_flush_range
228ENDPROC(fa_dma_map_area)
229
230/*
231 *	dma_unmap_area(start, size, dir)
232 *	- start	- kernel virtual start address
233 *	- size	- size of region
234 *	- dir	- DMA direction
235 */
236ENTRY(fa_dma_unmap_area)
237	ret	lr
238ENDPROC(fa_dma_unmap_area)
239
240	.globl	fa_flush_kern_cache_louis
241	.equ	fa_flush_kern_cache_louis, fa_flush_kern_cache_all
242
243	__INITDATA
244
245	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
246	define_cache_functions fa
247