xref: /linux/arch/arm/mm/cache-v7.S (revision 31d166642c7c601c65eccf0ff2e0afe9a0538be2)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *  linux/arch/arm/mm/cache-v7.S
4 *
5 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
6 *  Copyright (C) 2005 ARM Ltd.
7 *
8 *  This is the "shell" of the ARMv7 processor support.
9 */
10#include <linux/linkage.h>
11#include <linux/init.h>
12#include <asm/assembler.h>
13#include <asm/errno.h>
14#include <asm/unwind.h>
15#include <asm/hardware/cache-b15-rac.h>
16
17#include "proc-macros.S"
18
19/*
20 * The secondary kernel init calls v7_flush_dcache_all before it enables
21 * the L1; however, the L1 comes out of reset in an undefined state, so
22 * the clean + invalidate performed by v7_flush_dcache_all causes a bunch
23 * of cache lines with uninitialized data and uninitialized tags to get
24 * written out to memory, which does really unpleasant things to the main
25 * processor.  We fix this by performing an invalidate, rather than a
26 * clean + invalidate, before jumping into the kernel.
27 *
28 * This function is cloned from arch/arm/mach-tegra/headsmp.S, and needs
29 * to be called for both secondary cores startup and primary core resume
30 * procedures.
31 */
32ENTRY(v7_invalidate_l1)
33       mov     r0, #0
34       mcr     p15, 2, r0, c0, c0, 0
35       mrc     p15, 1, r0, c0, c0, 0
36
37       movw    r1, #0x7fff
38       and     r2, r1, r0, lsr #13
39
40       movw    r1, #0x3ff
41
42       and     r3, r1, r0, lsr #3      @ NumWays - 1
43       add     r2, r2, #1              @ NumSets
44
45       and     r0, r0, #0x7
46       add     r0, r0, #4      @ SetShift
47
48       clz     r1, r3          @ WayShift
49       add     r4, r3, #1      @ NumWays
501:     sub     r2, r2, #1      @ NumSets--
51       mov     r3, r4          @ Temp = NumWays
522:     subs    r3, r3, #1      @ Temp--
53       mov     r5, r3, lsl r1
54       mov     r6, r2, lsl r0
55       orr     r5, r5, r6      @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
56       mcr     p15, 0, r5, c7, c6, 2
57       bgt     2b
58       cmp     r2, #0
59       bgt     1b
60       dsb     st
61       isb
62       ret     lr
63ENDPROC(v7_invalidate_l1)
64
65/*
66 *	v7_flush_icache_all()
67 *
68 *	Flush the whole I-cache.
69 *
70 *	Registers:
71 *	r0 - set to 0
72 */
73ENTRY(v7_flush_icache_all)
74	mov	r0, #0
75	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)		@ invalidate I-cache inner shareable
76	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)		@ I+BTB cache invalidate
77	ret	lr
78ENDPROC(v7_flush_icache_all)
79
80 /*
81 *     v7_flush_dcache_louis()
82 *
83 *     Flush the D-cache up to the Level of Unification Inner Shareable
84 *
85 *     Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
86 */
87
88ENTRY(v7_flush_dcache_louis)
89	dmb					@ ensure ordering with previous memory accesses
90	mrc	p15, 1, r0, c0, c0, 1		@ read clidr, r0 = clidr
91ALT_SMP(mov	r3, r0, lsr #20)		@ move LoUIS into position
92ALT_UP(	mov	r3, r0, lsr #26)		@ move LoUU into position
93	ands	r3, r3, #7 << 1 		@ extract LoU*2 field from clidr
94	bne	start_flush_levels		@ LoU != 0, start flushing
95#ifdef CONFIG_ARM_ERRATA_643719
96ALT_SMP(mrc	p15, 0, r2, c0, c0, 0)		@ read main ID register
97ALT_UP(	ret	lr)				@ LoUU is zero, so nothing to do
98	movw	r1, #:lower16:(0x410fc090 >> 4)	@ ID of ARM Cortex A9 r0p?
99	movt	r1, #:upper16:(0x410fc090 >> 4)
100	teq	r1, r2, lsr #4			@ test for errata affected core and if so...
101	moveq	r3, #1 << 1			@   fix LoUIS value
102	beq	start_flush_levels		@   start flushing cache levels
103#endif
104	ret	lr
105ENDPROC(v7_flush_dcache_louis)
106
107/*
108 *	v7_flush_dcache_all()
109 *
110 *	Flush the whole D-cache.
111 *
112 *	Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
113 *
114 *	- mm    - mm_struct describing address space
115 */
116ENTRY(v7_flush_dcache_all)
117	dmb					@ ensure ordering with previous memory accesses
118	mrc	p15, 1, r0, c0, c0, 1		@ read clidr
119	mov	r3, r0, lsr #23			@ move LoC into position
120	ands	r3, r3, #7 << 1			@ extract LoC*2 from clidr
121	beq	finished			@ if loc is 0, then no need to clean
122start_flush_levels:
123	mov	r10, #0				@ start clean at cache level 0
124flush_levels:
125	add	r2, r10, r10, lsr #1		@ work out 3x current cache level
126	mov	r1, r0, lsr r2			@ extract cache type bits from clidr
127	and	r1, r1, #7			@ mask of the bits for current cache only
128	cmp	r1, #2				@ see what cache we have at this level
129	blt	skip				@ skip if no cache, or just i-cache
130#ifdef CONFIG_PREEMPT
131	save_and_disable_irqs_notrace r9	@ make cssr&csidr read atomic
132#endif
133	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
134	isb					@ isb to sych the new cssr&csidr
135	mrc	p15, 1, r1, c0, c0, 0		@ read the new csidr
136#ifdef CONFIG_PREEMPT
137	restore_irqs_notrace r9
138#endif
139	and	r2, r1, #7			@ extract the length of the cache lines
140	add	r2, r2, #4			@ add 4 (line length offset)
141	movw	r4, #0x3ff
142	ands	r4, r4, r1, lsr #3		@ find maximum number on the way size
143	clz	r5, r4				@ find bit position of way size increment
144	movw	r7, #0x7fff
145	ands	r7, r7, r1, lsr #13		@ extract max number of the index size
146loop1:
147	mov	r9, r7				@ create working copy of max index
148loop2:
149 ARM(	orr	r11, r10, r4, lsl r5	)	@ factor way and cache number into r11
150 THUMB(	lsl	r6, r4, r5		)
151 THUMB(	orr	r11, r10, r6		)	@ factor way and cache number into r11
152 ARM(	orr	r11, r11, r9, lsl r2	)	@ factor index number into r11
153 THUMB(	lsl	r6, r9, r2		)
154 THUMB(	orr	r11, r11, r6		)	@ factor index number into r11
155	mcr	p15, 0, r11, c7, c14, 2		@ clean & invalidate by set/way
156	subs	r9, r9, #1			@ decrement the index
157	bge	loop2
158	subs	r4, r4, #1			@ decrement the way
159	bge	loop1
160skip:
161	add	r10, r10, #2			@ increment cache number
162	cmp	r3, r10
163	bgt	flush_levels
164finished:
165	mov	r10, #0				@ switch back to cache level 0
166	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
167	dsb	st
168	isb
169	ret	lr
170ENDPROC(v7_flush_dcache_all)
171
172/*
173 *	v7_flush_cache_all()
174 *
175 *	Flush the entire cache system.
176 *  The data cache flush is now achieved using atomic clean / invalidates
177 *  working outwards from L1 cache. This is done using Set/Way based cache
178 *  maintenance instructions.
179 *  The instruction cache can still be invalidated back to the point of
180 *  unification in a single instruction.
181 *
182 */
183ENTRY(v7_flush_kern_cache_all)
184 ARM(	stmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
185 THUMB(	stmfd	sp!, {r4-r7, r9-r11, lr}	)
186	bl	v7_flush_dcache_all
187	mov	r0, #0
188	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)	@ invalidate I-cache inner shareable
189	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)	@ I+BTB cache invalidate
190 ARM(	ldmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
191 THUMB(	ldmfd	sp!, {r4-r7, r9-r11, lr}	)
192	ret	lr
193ENDPROC(v7_flush_kern_cache_all)
194
195 /*
196 *     v7_flush_kern_cache_louis(void)
197 *
198 *     Flush the data cache up to Level of Unification Inner Shareable.
199 *     Invalidate the I-cache to the point of unification.
200 */
201ENTRY(v7_flush_kern_cache_louis)
202 ARM(	stmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
203 THUMB(	stmfd	sp!, {r4-r7, r9-r11, lr}	)
204	bl	v7_flush_dcache_louis
205	mov	r0, #0
206	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)	@ invalidate I-cache inner shareable
207	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)	@ I+BTB cache invalidate
208 ARM(	ldmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
209 THUMB(	ldmfd	sp!, {r4-r7, r9-r11, lr}	)
210	ret	lr
211ENDPROC(v7_flush_kern_cache_louis)
212
213/*
214 *	v7_flush_cache_all()
215 *
216 *	Flush all TLB entries in a particular address space
217 *
218 *	- mm    - mm_struct describing address space
219 */
220ENTRY(v7_flush_user_cache_all)
221	/*FALLTHROUGH*/
222
223/*
224 *	v7_flush_cache_range(start, end, flags)
225 *
226 *	Flush a range of TLB entries in the specified address space.
227 *
228 *	- start - start address (may not be aligned)
229 *	- end   - end address (exclusive, may not be aligned)
230 *	- flags	- vm_area_struct flags describing address space
231 *
232 *	It is assumed that:
233 *	- we have a VIPT cache.
234 */
235ENTRY(v7_flush_user_cache_range)
236	ret	lr
237ENDPROC(v7_flush_user_cache_all)
238ENDPROC(v7_flush_user_cache_range)
239
240/*
241 *	v7_coherent_kern_range(start,end)
242 *
243 *	Ensure that the I and D caches are coherent within specified
244 *	region.  This is typically used when code has been written to
245 *	a memory region, and will be executed.
246 *
247 *	- start   - virtual start address of region
248 *	- end     - virtual end address of region
249 *
250 *	It is assumed that:
251 *	- the Icache does not read data from the write buffer
252 */
253ENTRY(v7_coherent_kern_range)
254	/* FALLTHROUGH */
255
256/*
257 *	v7_coherent_user_range(start,end)
258 *
259 *	Ensure that the I and D caches are coherent within specified
260 *	region.  This is typically used when code has been written to
261 *	a memory region, and will be executed.
262 *
263 *	- start   - virtual start address of region
264 *	- end     - virtual end address of region
265 *
266 *	It is assumed that:
267 *	- the Icache does not read data from the write buffer
268 */
269ENTRY(v7_coherent_user_range)
270 UNWIND(.fnstart		)
271	dcache_line_size r2, r3
272	sub	r3, r2, #1
273	bic	r12, r0, r3
274#ifdef CONFIG_ARM_ERRATA_764369
275	ALT_SMP(W(dsb))
276	ALT_UP(W(nop))
277#endif
2781:
279 USER(	mcr	p15, 0, r12, c7, c11, 1	)	@ clean D line to the point of unification
280	add	r12, r12, r2
281	cmp	r12, r1
282	blo	1b
283	dsb	ishst
284	icache_line_size r2, r3
285	sub	r3, r2, #1
286	bic	r12, r0, r3
2872:
288 USER(	mcr	p15, 0, r12, c7, c5, 1	)	@ invalidate I line
289	add	r12, r12, r2
290	cmp	r12, r1
291	blo	2b
292	mov	r0, #0
293	ALT_SMP(mcr	p15, 0, r0, c7, c1, 6)	@ invalidate BTB Inner Shareable
294	ALT_UP(mcr	p15, 0, r0, c7, c5, 6)	@ invalidate BTB
295	dsb	ishst
296	isb
297	ret	lr
298
299/*
300 * Fault handling for the cache operation above. If the virtual address in r0
301 * isn't mapped, fail with -EFAULT.
302 */
3039001:
304#ifdef CONFIG_ARM_ERRATA_775420
305	dsb
306#endif
307	mov	r0, #-EFAULT
308	ret	lr
309 UNWIND(.fnend		)
310ENDPROC(v7_coherent_kern_range)
311ENDPROC(v7_coherent_user_range)
312
313/*
314 *	v7_flush_kern_dcache_area(void *addr, size_t size)
315 *
316 *	Ensure that the data held in the page kaddr is written back
317 *	to the page in question.
318 *
319 *	- addr	- kernel address
320 *	- size	- region size
321 */
322ENTRY(v7_flush_kern_dcache_area)
323	dcache_line_size r2, r3
324	add	r1, r0, r1
325	sub	r3, r2, #1
326	bic	r0, r0, r3
327#ifdef CONFIG_ARM_ERRATA_764369
328	ALT_SMP(W(dsb))
329	ALT_UP(W(nop))
330#endif
3311:
332	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line / unified line
333	add	r0, r0, r2
334	cmp	r0, r1
335	blo	1b
336	dsb	st
337	ret	lr
338ENDPROC(v7_flush_kern_dcache_area)
339
340/*
341 *	v7_dma_inv_range(start,end)
342 *
343 *	Invalidate the data cache within the specified region; we will
344 *	be performing a DMA operation in this region and we want to
345 *	purge old data in the cache.
346 *
347 *	- start   - virtual start address of region
348 *	- end     - virtual end address of region
349 */
350v7_dma_inv_range:
351	dcache_line_size r2, r3
352	sub	r3, r2, #1
353	tst	r0, r3
354	bic	r0, r0, r3
355#ifdef CONFIG_ARM_ERRATA_764369
356	ALT_SMP(W(dsb))
357	ALT_UP(W(nop))
358#endif
359	mcrne	p15, 0, r0, c7, c14, 1		@ clean & invalidate D / U line
360	addne	r0, r0, r2
361
362	tst	r1, r3
363	bic	r1, r1, r3
364	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D / U line
365	cmp	r0, r1
3661:
367	mcrlo	p15, 0, r0, c7, c6, 1		@ invalidate D / U line
368	addlo	r0, r0, r2
369	cmplo	r0, r1
370	blo	1b
371	dsb	st
372	ret	lr
373ENDPROC(v7_dma_inv_range)
374
375/*
376 *	v7_dma_clean_range(start,end)
377 *	- start   - virtual start address of region
378 *	- end     - virtual end address of region
379 */
380v7_dma_clean_range:
381	dcache_line_size r2, r3
382	sub	r3, r2, #1
383	bic	r0, r0, r3
384#ifdef CONFIG_ARM_ERRATA_764369
385	ALT_SMP(W(dsb))
386	ALT_UP(W(nop))
387#endif
3881:
389	mcr	p15, 0, r0, c7, c10, 1		@ clean D / U line
390	add	r0, r0, r2
391	cmp	r0, r1
392	blo	1b
393	dsb	st
394	ret	lr
395ENDPROC(v7_dma_clean_range)
396
397/*
398 *	v7_dma_flush_range(start,end)
399 *	- start   - virtual start address of region
400 *	- end     - virtual end address of region
401 */
402ENTRY(v7_dma_flush_range)
403	dcache_line_size r2, r3
404	sub	r3, r2, #1
405	bic	r0, r0, r3
406#ifdef CONFIG_ARM_ERRATA_764369
407	ALT_SMP(W(dsb))
408	ALT_UP(W(nop))
409#endif
4101:
411	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D / U line
412	add	r0, r0, r2
413	cmp	r0, r1
414	blo	1b
415	dsb	st
416	ret	lr
417ENDPROC(v7_dma_flush_range)
418
419/*
420 *	dma_map_area(start, size, dir)
421 *	- start	- kernel virtual start address
422 *	- size	- size of region
423 *	- dir	- DMA direction
424 */
425ENTRY(v7_dma_map_area)
426	add	r1, r1, r0
427	teq	r2, #DMA_FROM_DEVICE
428	beq	v7_dma_inv_range
429	b	v7_dma_clean_range
430ENDPROC(v7_dma_map_area)
431
432/*
433 *	dma_unmap_area(start, size, dir)
434 *	- start	- kernel virtual start address
435 *	- size	- size of region
436 *	- dir	- DMA direction
437 */
438ENTRY(v7_dma_unmap_area)
439	add	r1, r1, r0
440	teq	r2, #DMA_TO_DEVICE
441	bne	v7_dma_inv_range
442	ret	lr
443ENDPROC(v7_dma_unmap_area)
444
445	__INITDATA
446
447	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
448	define_cache_functions v7
449
450	/* The Broadcom Brahma-B15 read-ahead cache requires some modifications
451	 * to the v7_cache_fns, we only override the ones we need
452	 */
453#ifndef CONFIG_CACHE_B15_RAC
454	globl_equ	b15_flush_kern_cache_all,	v7_flush_kern_cache_all
455#endif
456	globl_equ	b15_flush_icache_all,		v7_flush_icache_all
457	globl_equ	b15_flush_kern_cache_louis,	v7_flush_kern_cache_louis
458	globl_equ	b15_flush_user_cache_all,	v7_flush_user_cache_all
459	globl_equ	b15_flush_user_cache_range,	v7_flush_user_cache_range
460	globl_equ	b15_coherent_kern_range,	v7_coherent_kern_range
461	globl_equ	b15_coherent_user_range,	v7_coherent_user_range
462	globl_equ	b15_flush_kern_dcache_area,	v7_flush_kern_dcache_area
463
464	globl_equ	b15_dma_map_area,		v7_dma_map_area
465	globl_equ	b15_dma_unmap_area,		v7_dma_unmap_area
466	globl_equ	b15_dma_flush_range,		v7_dma_flush_range
467
468	define_cache_functions b15
469