xref: /openbmc/linux/arch/arm/mm/cache-fa.S (revision b593bce5)
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/memory.h>
17#include <asm/page.h>
18
19#include "proc-macros.S"
20
21/*
22 * The size of one data cache line.
23 */
24#define CACHE_DLINESIZE	16
25
26/*
27 * The total size of the data cache.
28 */
29#ifdef CONFIG_ARCH_GEMINI
30#define CACHE_DSIZE	8192
31#else
32#define CACHE_DSIZE	16384
33#endif
34
35/* FIXME: put optimal value here. Current one is just estimation */
36#define CACHE_DLIMIT	(CACHE_DSIZE * 2)
37
38/*
39 *	flush_icache_all()
40 *
41 *	Unconditionally clean and invalidate the entire icache.
42 */
43ENTRY(fa_flush_icache_all)
44	mov	r0, #0
45	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
46	ret	lr
47ENDPROC(fa_flush_icache_all)
48
49/*
50 *	flush_user_cache_all()
51 *
52 *	Clean and invalidate all cache entries in a particular address
53 *	space.
54 */
55ENTRY(fa_flush_user_cache_all)
56	/* FALLTHROUGH */
57/*
58 *	flush_kern_cache_all()
59 *
60 *	Clean and invalidate the entire cache.
61 */
62ENTRY(fa_flush_kern_cache_all)
63	mov	ip, #0
64	mov	r2, #VM_EXEC
65__flush_whole_cache:
66	mcr	p15, 0, ip, c7, c14, 0		@ clean/invalidate D cache
67	tst	r2, #VM_EXEC
68	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
69	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
70	mcrne	p15, 0, ip, c7, c10, 4		@ drain write buffer
71	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
72	ret	lr
73
74/*
75 *	flush_user_cache_range(start, end, flags)
76 *
77 *	Invalidate a range of cache entries in the specified
78 *	address space.
79 *
80 *	- start - start address (inclusive, page aligned)
81 *	- end	- end address (exclusive, page aligned)
82 *	- flags	- vma_area_struct flags describing address space
83 */
84ENTRY(fa_flush_user_cache_range)
85	mov	ip, #0
86	sub	r3, r1, r0			@ calculate total size
87	cmp	r3, #CACHE_DLIMIT		@ total size >= limit?
88	bhs	__flush_whole_cache		@ flush whole D cache
89
901:	tst	r2, #VM_EXEC
91	mcrne	p15, 0, r0, c7, c5, 1		@ invalidate I line
92	mcr	p15, 0, r0, c7, c14, 1		@ clean and invalidate D entry
93	add	r0, r0, #CACHE_DLINESIZE
94	cmp	r0, r1
95	blo	1b
96	tst	r2, #VM_EXEC
97	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
98	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
99	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
100	ret	lr
101
102/*
103 *	coherent_kern_range(start, end)
104 *
105 *	Ensure coherency between the Icache and the Dcache in the
106 *	region described by start.  If you have non-snooping
107 *	Harvard caches, you need to implement this function.
108 *
109 *	- start  - virtual start address
110 *	- end	 - virtual end address
111 */
112ENTRY(fa_coherent_kern_range)
113	/* fall through */
114
115/*
116 *	coherent_user_range(start, end)
117 *
118 *	Ensure coherency between the Icache and the Dcache in the
119 *	region described by start.  If you have non-snooping
120 *	Harvard caches, you need to implement this function.
121 *
122 *	- start  - virtual start address
123 *	- end	 - virtual end address
124 */
125ENTRY(fa_coherent_user_range)
126	bic	r0, r0, #CACHE_DLINESIZE - 1
1271:	mcr	p15, 0, r0, c7, c14, 1		@ clean and invalidate D entry
128	mcr	p15, 0, r0, c7, c5, 1		@ invalidate I entry
129	add	r0, r0, #CACHE_DLINESIZE
130	cmp	r0, r1
131	blo	1b
132	mov	r0, #0
133	mcr	p15, 0, r0, c7, c5, 6		@ invalidate BTB
134	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
135	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
136	ret	lr
137
138/*
139 *	flush_kern_dcache_area(void *addr, size_t size)
140 *
141 *	Ensure that the data held in the page kaddr is written back
142 *	to the page in question.
143 *
144 *	- addr	- kernel address
145 *	- size	- size of region
146 */
147ENTRY(fa_flush_kern_dcache_area)
148	add	r1, r0, r1
1491:	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
150	add	r0, r0, #CACHE_DLINESIZE
151	cmp	r0, r1
152	blo	1b
153	mov	r0, #0
154	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
155	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
156	ret	lr
157
158/*
159 *	dma_inv_range(start, end)
160 *
161 *	Invalidate (discard) the specified virtual address range.
162 *	May not write back any entries.  If 'start' or 'end'
163 *	are not cache line aligned, those lines must be written
164 *	back.
165 *
166 *	- start  - virtual start address
167 *	- end	 - virtual end address
168 */
169fa_dma_inv_range:
170	tst	r0, #CACHE_DLINESIZE - 1
171	bic	r0, r0, #CACHE_DLINESIZE - 1
172	mcrne	p15, 0, r0, c7, c14, 1		@ clean & invalidate D entry
173	tst	r1, #CACHE_DLINESIZE - 1
174	bic	r1, r1, #CACHE_DLINESIZE - 1
175	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D entry
1761:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
177	add	r0, r0, #CACHE_DLINESIZE
178	cmp	r0, r1
179	blo	1b
180	mov	r0, #0
181	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
182	ret	lr
183
184/*
185 *	dma_clean_range(start, end)
186 *
187 *	Clean (write back) the specified virtual address range.
188 *
189 *	- start  - virtual start address
190 *	- end	 - virtual end address
191 */
192fa_dma_clean_range:
193	bic	r0, r0, #CACHE_DLINESIZE - 1
1941:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
195	add	r0, r0, #CACHE_DLINESIZE
196	cmp	r0, r1
197	blo	1b
198	mov	r0, #0
199	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
200	ret	lr
201
202/*
203 *	dma_flush_range(start,end)
204 *	- start   - virtual start address of region
205 *	- end     - virtual end address of region
206 */
207ENTRY(fa_dma_flush_range)
208	bic	r0, r0, #CACHE_DLINESIZE - 1
2091:	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D entry
210	add	r0, r0, #CACHE_DLINESIZE
211	cmp	r0, r1
212	blo	1b
213	mov	r0, #0
214	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
215	ret	lr
216
217/*
218 *	dma_map_area(start, size, dir)
219 *	- start	- kernel virtual start address
220 *	- size	- size of region
221 *	- dir	- DMA direction
222 */
223ENTRY(fa_dma_map_area)
224	add	r1, r1, r0
225	cmp	r2, #DMA_TO_DEVICE
226	beq	fa_dma_clean_range
227	bcs	fa_dma_inv_range
228	b	fa_dma_flush_range
229ENDPROC(fa_dma_map_area)
230
231/*
232 *	dma_unmap_area(start, size, dir)
233 *	- start	- kernel virtual start address
234 *	- size	- size of region
235 *	- dir	- DMA direction
236 */
237ENTRY(fa_dma_unmap_area)
238	ret	lr
239ENDPROC(fa_dma_unmap_area)
240
241	.globl	fa_flush_kern_cache_louis
242	.equ	fa_flush_kern_cache_louis, fa_flush_kern_cache_all
243
244	__INITDATA
245
246	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
247	define_cache_functions fa
248