xref: /linux/arch/arm/mm/cache-v7.S (revision d4ce5458ea1b7d8ca49c436d602095c4912777d3)
1/*
2 *  linux/arch/arm/mm/cache-v7.S
3 *
4 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
5 *  Copyright (C) 2005 ARM Ltd.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 *  This is the "shell" of the ARMv7 processor support.
12 */
13#include <linux/linkage.h>
14#include <linux/init.h>
15#include <asm/assembler.h>
16#include <asm/errno.h>
17#include <asm/unwind.h>
18#include <asm/hardware/cache-b15-rac.h>
19
20#include "proc-macros.S"
21
22/*
23 * The secondary kernel init calls v7_flush_dcache_all before it enables
24 * the L1; however, the L1 comes out of reset in an undefined state, so
25 * the clean + invalidate performed by v7_flush_dcache_all causes a bunch
26 * of cache lines with uninitialized data and uninitialized tags to get
27 * written out to memory, which does really unpleasant things to the main
28 * processor.  We fix this by performing an invalidate, rather than a
29 * clean + invalidate, before jumping into the kernel.
30 *
31 * This function is cloned from arch/arm/mach-tegra/headsmp.S, and needs
32 * to be called for both secondary cores startup and primary core resume
33 * procedures.
34 */
35ENTRY(v7_invalidate_l1)
36       mov     r0, #0
37       mcr     p15, 2, r0, c0, c0, 0
38       mrc     p15, 1, r0, c0, c0, 0
39
40       movw    r1, #0x7fff
41       and     r2, r1, r0, lsr #13
42
43       movw    r1, #0x3ff
44
45       and     r3, r1, r0, lsr #3      @ NumWays - 1
46       add     r2, r2, #1              @ NumSets
47
48       and     r0, r0, #0x7
49       add     r0, r0, #4      @ SetShift
50
51       clz     r1, r3          @ WayShift
52       add     r4, r3, #1      @ NumWays
531:     sub     r2, r2, #1      @ NumSets--
54       mov     r3, r4          @ Temp = NumWays
552:     subs    r3, r3, #1      @ Temp--
56       mov     r5, r3, lsl r1
57       mov     r6, r2, lsl r0
58       orr     r5, r5, r6      @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
59       mcr     p15, 0, r5, c7, c6, 2
60       bgt     2b
61       cmp     r2, #0
62       bgt     1b
63       dsb     st
64       isb
65       ret     lr
66ENDPROC(v7_invalidate_l1)
67
68/*
69 *	v7_flush_icache_all()
70 *
71 *	Flush the whole I-cache.
72 *
73 *	Registers:
74 *	r0 - set to 0
75 */
76ENTRY(v7_flush_icache_all)
77	mov	r0, #0
78	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)		@ invalidate I-cache inner shareable
79	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)		@ I+BTB cache invalidate
80	ret	lr
81ENDPROC(v7_flush_icache_all)
82
83 /*
84 *     v7_flush_dcache_louis()
85 *
86 *     Flush the D-cache up to the Level of Unification Inner Shareable
87 *
88 *     Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
89 */
90
91ENTRY(v7_flush_dcache_louis)
92	dmb					@ ensure ordering with previous memory accesses
93	mrc	p15, 1, r0, c0, c0, 1		@ read clidr, r0 = clidr
94ALT_SMP(mov	r3, r0, lsr #20)		@ move LoUIS into position
95ALT_UP(	mov	r3, r0, lsr #26)		@ move LoUU into position
96	ands	r3, r3, #7 << 1 		@ extract LoU*2 field from clidr
97	bne	start_flush_levels		@ LoU != 0, start flushing
98#ifdef CONFIG_ARM_ERRATA_643719
99ALT_SMP(mrc	p15, 0, r2, c0, c0, 0)		@ read main ID register
100ALT_UP(	ret	lr)				@ LoUU is zero, so nothing to do
101	movw	r1, #:lower16:(0x410fc090 >> 4)	@ ID of ARM Cortex A9 r0p?
102	movt	r1, #:upper16:(0x410fc090 >> 4)
103	teq	r1, r2, lsr #4			@ test for errata affected core and if so...
104	moveq	r3, #1 << 1			@   fix LoUIS value
105	beq	start_flush_levels		@   start flushing cache levels
106#endif
107	ret	lr
108ENDPROC(v7_flush_dcache_louis)
109
110/*
111 *	v7_flush_dcache_all()
112 *
113 *	Flush the whole D-cache.
114 *
115 *	Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
116 *
117 *	- mm    - mm_struct describing address space
118 */
119ENTRY(v7_flush_dcache_all)
120	dmb					@ ensure ordering with previous memory accesses
121	mrc	p15, 1, r0, c0, c0, 1		@ read clidr
122	mov	r3, r0, lsr #23			@ move LoC into position
123	ands	r3, r3, #7 << 1			@ extract LoC*2 from clidr
124	beq	finished			@ if loc is 0, then no need to clean
125start_flush_levels:
126	mov	r10, #0				@ start clean at cache level 0
127flush_levels:
128	add	r2, r10, r10, lsr #1		@ work out 3x current cache level
129	mov	r1, r0, lsr r2			@ extract cache type bits from clidr
130	and	r1, r1, #7			@ mask of the bits for current cache only
131	cmp	r1, #2				@ see what cache we have at this level
132	blt	skip				@ skip if no cache, or just i-cache
133#ifdef CONFIG_PREEMPT
134	save_and_disable_irqs_notrace r9	@ make cssr&csidr read atomic
135#endif
136	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
137	isb					@ isb to sych the new cssr&csidr
138	mrc	p15, 1, r1, c0, c0, 0		@ read the new csidr
139#ifdef CONFIG_PREEMPT
140	restore_irqs_notrace r9
141#endif
142	and	r2, r1, #7			@ extract the length of the cache lines
143	add	r2, r2, #4			@ add 4 (line length offset)
144	movw	r4, #0x3ff
145	ands	r4, r4, r1, lsr #3		@ find maximum number on the way size
146	clz	r5, r4				@ find bit position of way size increment
147	movw	r7, #0x7fff
148	ands	r7, r7, r1, lsr #13		@ extract max number of the index size
149loop1:
150	mov	r9, r7				@ create working copy of max index
151loop2:
152 ARM(	orr	r11, r10, r4, lsl r5	)	@ factor way and cache number into r11
153 THUMB(	lsl	r6, r4, r5		)
154 THUMB(	orr	r11, r10, r6		)	@ factor way and cache number into r11
155 ARM(	orr	r11, r11, r9, lsl r2	)	@ factor index number into r11
156 THUMB(	lsl	r6, r9, r2		)
157 THUMB(	orr	r11, r11, r6		)	@ factor index number into r11
158	mcr	p15, 0, r11, c7, c14, 2		@ clean & invalidate by set/way
159	subs	r9, r9, #1			@ decrement the index
160	bge	loop2
161	subs	r4, r4, #1			@ decrement the way
162	bge	loop1
163skip:
164	add	r10, r10, #2			@ increment cache number
165	cmp	r3, r10
166	bgt	flush_levels
167finished:
168	mov	r10, #0				@ switch back to cache level 0
169	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
170	dsb	st
171	isb
172	ret	lr
173ENDPROC(v7_flush_dcache_all)
174
175/*
176 *	v7_flush_cache_all()
177 *
178 *	Flush the entire cache system.
179 *  The data cache flush is now achieved using atomic clean / invalidates
180 *  working outwards from L1 cache. This is done using Set/Way based cache
181 *  maintenance instructions.
182 *  The instruction cache can still be invalidated back to the point of
183 *  unification in a single instruction.
184 *
185 */
186ENTRY(v7_flush_kern_cache_all)
187 ARM(	stmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
188 THUMB(	stmfd	sp!, {r4-r7, r9-r11, lr}	)
189	bl	v7_flush_dcache_all
190	mov	r0, #0
191	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)	@ invalidate I-cache inner shareable
192	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)	@ I+BTB cache invalidate
193 ARM(	ldmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
194 THUMB(	ldmfd	sp!, {r4-r7, r9-r11, lr}	)
195	ret	lr
196ENDPROC(v7_flush_kern_cache_all)
197
198 /*
199 *     v7_flush_kern_cache_louis(void)
200 *
201 *     Flush the data cache up to Level of Unification Inner Shareable.
202 *     Invalidate the I-cache to the point of unification.
203 */
204ENTRY(v7_flush_kern_cache_louis)
205 ARM(	stmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
206 THUMB(	stmfd	sp!, {r4-r7, r9-r11, lr}	)
207	bl	v7_flush_dcache_louis
208	mov	r0, #0
209	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)	@ invalidate I-cache inner shareable
210	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)	@ I+BTB cache invalidate
211 ARM(	ldmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
212 THUMB(	ldmfd	sp!, {r4-r7, r9-r11, lr}	)
213	ret	lr
214ENDPROC(v7_flush_kern_cache_louis)
215
216/*
217 *	v7_flush_cache_all()
218 *
219 *	Flush all TLB entries in a particular address space
220 *
221 *	- mm    - mm_struct describing address space
222 */
223ENTRY(v7_flush_user_cache_all)
224	/*FALLTHROUGH*/
225
226/*
227 *	v7_flush_cache_range(start, end, flags)
228 *
229 *	Flush a range of TLB entries in the specified address space.
230 *
231 *	- start - start address (may not be aligned)
232 *	- end   - end address (exclusive, may not be aligned)
233 *	- flags	- vm_area_struct flags describing address space
234 *
235 *	It is assumed that:
236 *	- we have a VIPT cache.
237 */
238ENTRY(v7_flush_user_cache_range)
239	ret	lr
240ENDPROC(v7_flush_user_cache_all)
241ENDPROC(v7_flush_user_cache_range)
242
243/*
244 *	v7_coherent_kern_range(start,end)
245 *
246 *	Ensure that the I and D caches are coherent within specified
247 *	region.  This is typically used when code has been written to
248 *	a memory region, and will be executed.
249 *
250 *	- start   - virtual start address of region
251 *	- end     - virtual end address of region
252 *
253 *	It is assumed that:
254 *	- the Icache does not read data from the write buffer
255 */
256ENTRY(v7_coherent_kern_range)
257	/* FALLTHROUGH */
258
259/*
260 *	v7_coherent_user_range(start,end)
261 *
262 *	Ensure that the I and D caches are coherent within specified
263 *	region.  This is typically used when code has been written to
264 *	a memory region, and will be executed.
265 *
266 *	- start   - virtual start address of region
267 *	- end     - virtual end address of region
268 *
269 *	It is assumed that:
270 *	- the Icache does not read data from the write buffer
271 */
272ENTRY(v7_coherent_user_range)
273 UNWIND(.fnstart		)
274	dcache_line_size r2, r3
275	sub	r3, r2, #1
276	bic	r12, r0, r3
277#ifdef CONFIG_ARM_ERRATA_764369
278	ALT_SMP(W(dsb))
279	ALT_UP(W(nop))
280#endif
2811:
282 USER(	mcr	p15, 0, r12, c7, c11, 1	)	@ clean D line to the point of unification
283	add	r12, r12, r2
284	cmp	r12, r1
285	blo	1b
286	dsb	ishst
287	icache_line_size r2, r3
288	sub	r3, r2, #1
289	bic	r12, r0, r3
2902:
291 USER(	mcr	p15, 0, r12, c7, c5, 1	)	@ invalidate I line
292	add	r12, r12, r2
293	cmp	r12, r1
294	blo	2b
295	mov	r0, #0
296	ALT_SMP(mcr	p15, 0, r0, c7, c1, 6)	@ invalidate BTB Inner Shareable
297	ALT_UP(mcr	p15, 0, r0, c7, c5, 6)	@ invalidate BTB
298	dsb	ishst
299	isb
300	ret	lr
301
302/*
303 * Fault handling for the cache operation above. If the virtual address in r0
304 * isn't mapped, fail with -EFAULT.
305 */
3069001:
307#ifdef CONFIG_ARM_ERRATA_775420
308	dsb
309#endif
310	mov	r0, #-EFAULT
311	ret	lr
312 UNWIND(.fnend		)
313ENDPROC(v7_coherent_kern_range)
314ENDPROC(v7_coherent_user_range)
315
316/*
317 *	v7_flush_kern_dcache_area(void *addr, size_t size)
318 *
319 *	Ensure that the data held in the page kaddr is written back
320 *	to the page in question.
321 *
322 *	- addr	- kernel address
323 *	- size	- region size
324 */
325ENTRY(v7_flush_kern_dcache_area)
326	dcache_line_size r2, r3
327	add	r1, r0, r1
328	sub	r3, r2, #1
329	bic	r0, r0, r3
330#ifdef CONFIG_ARM_ERRATA_764369
331	ALT_SMP(W(dsb))
332	ALT_UP(W(nop))
333#endif
3341:
335	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line / unified line
336	add	r0, r0, r2
337	cmp	r0, r1
338	blo	1b
339	dsb	st
340	ret	lr
341ENDPROC(v7_flush_kern_dcache_area)
342
343/*
344 *	v7_dma_inv_range(start,end)
345 *
346 *	Invalidate the data cache within the specified region; we will
347 *	be performing a DMA operation in this region and we want to
348 *	purge old data in the cache.
349 *
350 *	- start   - virtual start address of region
351 *	- end     - virtual end address of region
352 */
353v7_dma_inv_range:
354	dcache_line_size r2, r3
355	sub	r3, r2, #1
356	tst	r0, r3
357	bic	r0, r0, r3
358#ifdef CONFIG_ARM_ERRATA_764369
359	ALT_SMP(W(dsb))
360	ALT_UP(W(nop))
361#endif
362	mcrne	p15, 0, r0, c7, c14, 1		@ clean & invalidate D / U line
363	addne	r0, r0, r2
364
365	tst	r1, r3
366	bic	r1, r1, r3
367	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D / U line
368	cmp	r0, r1
3691:
370	mcrlo	p15, 0, r0, c7, c6, 1		@ invalidate D / U line
371	addlo	r0, r0, r2
372	cmplo	r0, r1
373	blo	1b
374	dsb	st
375	ret	lr
376ENDPROC(v7_dma_inv_range)
377
378/*
379 *	v7_dma_clean_range(start,end)
380 *	- start   - virtual start address of region
381 *	- end     - virtual end address of region
382 */
383v7_dma_clean_range:
384	dcache_line_size r2, r3
385	sub	r3, r2, #1
386	bic	r0, r0, r3
387#ifdef CONFIG_ARM_ERRATA_764369
388	ALT_SMP(W(dsb))
389	ALT_UP(W(nop))
390#endif
3911:
392	mcr	p15, 0, r0, c7, c10, 1		@ clean D / U line
393	add	r0, r0, r2
394	cmp	r0, r1
395	blo	1b
396	dsb	st
397	ret	lr
398ENDPROC(v7_dma_clean_range)
399
400/*
401 *	v7_dma_flush_range(start,end)
402 *	- start   - virtual start address of region
403 *	- end     - virtual end address of region
404 */
405ENTRY(v7_dma_flush_range)
406	dcache_line_size r2, r3
407	sub	r3, r2, #1
408	bic	r0, r0, r3
409#ifdef CONFIG_ARM_ERRATA_764369
410	ALT_SMP(W(dsb))
411	ALT_UP(W(nop))
412#endif
4131:
414	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D / U line
415	add	r0, r0, r2
416	cmp	r0, r1
417	blo	1b
418	dsb	st
419	ret	lr
420ENDPROC(v7_dma_flush_range)
421
422/*
423 *	dma_map_area(start, size, dir)
424 *	- start	- kernel virtual start address
425 *	- size	- size of region
426 *	- dir	- DMA direction
427 */
428ENTRY(v7_dma_map_area)
429	add	r1, r1, r0
430	teq	r2, #DMA_FROM_DEVICE
431	beq	v7_dma_inv_range
432	b	v7_dma_clean_range
433ENDPROC(v7_dma_map_area)
434
435/*
436 *	dma_unmap_area(start, size, dir)
437 *	- start	- kernel virtual start address
438 *	- size	- size of region
439 *	- dir	- DMA direction
440 */
441ENTRY(v7_dma_unmap_area)
442	add	r1, r1, r0
443	teq	r2, #DMA_TO_DEVICE
444	bne	v7_dma_inv_range
445	ret	lr
446ENDPROC(v7_dma_unmap_area)
447
448	__INITDATA
449
450	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
451	define_cache_functions v7
452
453	/* The Broadcom Brahma-B15 read-ahead cache requires some modifications
454	 * to the v7_cache_fns, we only override the ones we need
455	 */
456#ifndef CONFIG_CACHE_B15_RAC
457	globl_equ	b15_flush_kern_cache_all,	v7_flush_kern_cache_all
458#endif
459	globl_equ	b15_flush_icache_all,		v7_flush_icache_all
460	globl_equ	b15_flush_kern_cache_louis,	v7_flush_kern_cache_louis
461	globl_equ	b15_flush_user_cache_all,	v7_flush_user_cache_all
462	globl_equ	b15_flush_user_cache_range,	v7_flush_user_cache_range
463	globl_equ	b15_coherent_kern_range,	v7_coherent_kern_range
464	globl_equ	b15_coherent_user_range,	v7_coherent_user_range
465	globl_equ	b15_flush_kern_dcache_area,	v7_flush_kern_dcache_area
466
467	globl_equ	b15_dma_map_area,		v7_dma_map_area
468	globl_equ	b15_dma_unmap_area,		v7_dma_unmap_area
469	globl_equ	b15_dma_flush_range,		v7_dma_flush_range
470
471	define_cache_functions b15
472