xref: /openbmc/linux/arch/arm/mm/cache-v7.S (revision 4bb1eb3c)
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#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
20.globl icache_size
21	.data
22	.align	2
23icache_size:
24	.long	64
25	.text
26#endif
27/*
28 * The secondary kernel init calls v7_flush_dcache_all before it enables
29 * the L1; however, the L1 comes out of reset in an undefined state, so
30 * the clean + invalidate performed by v7_flush_dcache_all causes a bunch
31 * of cache lines with uninitialized data and uninitialized tags to get
32 * written out to memory, which does really unpleasant things to the main
33 * processor.  We fix this by performing an invalidate, rather than a
34 * clean + invalidate, before jumping into the kernel.
35 *
36 * This function is cloned from arch/arm/mach-tegra/headsmp.S, and needs
37 * to be called for both secondary cores startup and primary core resume
38 * procedures.
39 */
40ENTRY(v7_invalidate_l1)
41       mov     r0, #0
42       mcr     p15, 2, r0, c0, c0, 0
43       mrc     p15, 1, r0, c0, c0, 0
44
45       movw    r1, #0x7fff
46       and     r2, r1, r0, lsr #13
47
48       movw    r1, #0x3ff
49
50       and     r3, r1, r0, lsr #3      @ NumWays - 1
51       add     r2, r2, #1              @ NumSets
52
53       and     r0, r0, #0x7
54       add     r0, r0, #4      @ SetShift
55
56       clz     r1, r3          @ WayShift
57       add     r4, r3, #1      @ NumWays
581:     sub     r2, r2, #1      @ NumSets--
59       mov     r3, r4          @ Temp = NumWays
602:     subs    r3, r3, #1      @ Temp--
61       mov     r5, r3, lsl r1
62       mov     r6, r2, lsl r0
63       orr     r5, r5, r6      @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
64       mcr     p15, 0, r5, c7, c6, 2
65       bgt     2b
66       cmp     r2, #0
67       bgt     1b
68       dsb     st
69       isb
70       ret     lr
71ENDPROC(v7_invalidate_l1)
72
73/*
74 *	v7_flush_icache_all()
75 *
76 *	Flush the whole I-cache.
77 *
78 *	Registers:
79 *	r0 - set to 0
80 */
81ENTRY(v7_flush_icache_all)
82	mov	r0, #0
83	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)		@ invalidate I-cache inner shareable
84	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)		@ I+BTB cache invalidate
85	ret	lr
86ENDPROC(v7_flush_icache_all)
87
88 /*
89 *     v7_flush_dcache_louis()
90 *
91 *     Flush the D-cache up to the Level of Unification Inner Shareable
92 *
93 *     Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
94 */
95
96ENTRY(v7_flush_dcache_louis)
97	dmb					@ ensure ordering with previous memory accesses
98	mrc	p15, 1, r0, c0, c0, 1		@ read clidr, r0 = clidr
99ALT_SMP(mov	r3, r0, lsr #20)		@ move LoUIS into position
100ALT_UP(	mov	r3, r0, lsr #26)		@ move LoUU into position
101	ands	r3, r3, #7 << 1 		@ extract LoU*2 field from clidr
102	bne	start_flush_levels		@ LoU != 0, start flushing
103#ifdef CONFIG_ARM_ERRATA_643719
104ALT_SMP(mrc	p15, 0, r2, c0, c0, 0)		@ read main ID register
105ALT_UP(	ret	lr)				@ LoUU is zero, so nothing to do
106	movw	r1, #:lower16:(0x410fc090 >> 4)	@ ID of ARM Cortex A9 r0p?
107	movt	r1, #:upper16:(0x410fc090 >> 4)
108	teq	r1, r2, lsr #4			@ test for errata affected core and if so...
109	moveq	r3, #1 << 1			@   fix LoUIS value
110	beq	start_flush_levels		@   start flushing cache levels
111#endif
112	ret	lr
113ENDPROC(v7_flush_dcache_louis)
114
115/*
116 *	v7_flush_dcache_all()
117 *
118 *	Flush the whole D-cache.
119 *
120 *	Corrupted registers: r0-r7, r9-r11 (r6 only in Thumb mode)
121 *
122 *	- mm    - mm_struct describing address space
123 */
124ENTRY(v7_flush_dcache_all)
125	dmb					@ ensure ordering with previous memory accesses
126	mrc	p15, 1, r0, c0, c0, 1		@ read clidr
127	mov	r3, r0, lsr #23			@ move LoC into position
128	ands	r3, r3, #7 << 1			@ extract LoC*2 from clidr
129	beq	finished			@ if loc is 0, then no need to clean
130start_flush_levels:
131	mov	r10, #0				@ start clean at cache level 0
132flush_levels:
133	add	r2, r10, r10, lsr #1		@ work out 3x current cache level
134	mov	r1, r0, lsr r2			@ extract cache type bits from clidr
135	and	r1, r1, #7			@ mask of the bits for current cache only
136	cmp	r1, #2				@ see what cache we have at this level
137	blt	skip				@ skip if no cache, or just i-cache
138#ifdef CONFIG_PREEMPTION
139	save_and_disable_irqs_notrace r9	@ make cssr&csidr read atomic
140#endif
141	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
142	isb					@ isb to sych the new cssr&csidr
143	mrc	p15, 1, r1, c0, c0, 0		@ read the new csidr
144#ifdef CONFIG_PREEMPTION
145	restore_irqs_notrace r9
146#endif
147	and	r2, r1, #7			@ extract the length of the cache lines
148	add	r2, r2, #4			@ add 4 (line length offset)
149	movw	r4, #0x3ff
150	ands	r4, r4, r1, lsr #3		@ find maximum number on the way size
151	clz	r5, r4				@ find bit position of way size increment
152	movw	r7, #0x7fff
153	ands	r7, r7, r1, lsr #13		@ extract max number of the index size
154loop1:
155	mov	r9, r7				@ create working copy of max index
156loop2:
157 ARM(	orr	r11, r10, r4, lsl r5	)	@ factor way and cache number into r11
158 THUMB(	lsl	r6, r4, r5		)
159 THUMB(	orr	r11, r10, r6		)	@ factor way and cache number into r11
160 ARM(	orr	r11, r11, r9, lsl r2	)	@ factor index number into r11
161 THUMB(	lsl	r6, r9, r2		)
162 THUMB(	orr	r11, r11, r6		)	@ factor index number into r11
163	mcr	p15, 0, r11, c7, c14, 2		@ clean & invalidate by set/way
164	subs	r9, r9, #1			@ decrement the index
165	bge	loop2
166	subs	r4, r4, #1			@ decrement the way
167	bge	loop1
168skip:
169	add	r10, r10, #2			@ increment cache number
170	cmp	r3, r10
171#ifdef CONFIG_ARM_ERRATA_814220
172	dsb
173#endif
174	bgt	flush_levels
175finished:
176	mov	r10, #0				@ switch back to cache level 0
177	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
178	dsb	st
179	isb
180	ret	lr
181ENDPROC(v7_flush_dcache_all)
182
183/*
184 *	v7_flush_cache_all()
185 *
186 *	Flush the entire cache system.
187 *  The data cache flush is now achieved using atomic clean / invalidates
188 *  working outwards from L1 cache. This is done using Set/Way based cache
189 *  maintenance instructions.
190 *  The instruction cache can still be invalidated back to the point of
191 *  unification in a single instruction.
192 *
193 */
194ENTRY(v7_flush_kern_cache_all)
195 ARM(	stmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
196 THUMB(	stmfd	sp!, {r4-r7, r9-r11, lr}	)
197	bl	v7_flush_dcache_all
198	mov	r0, #0
199	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)	@ invalidate I-cache inner shareable
200	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)	@ I+BTB cache invalidate
201 ARM(	ldmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
202 THUMB(	ldmfd	sp!, {r4-r7, r9-r11, lr}	)
203	ret	lr
204ENDPROC(v7_flush_kern_cache_all)
205
206 /*
207 *     v7_flush_kern_cache_louis(void)
208 *
209 *     Flush the data cache up to Level of Unification Inner Shareable.
210 *     Invalidate the I-cache to the point of unification.
211 */
212ENTRY(v7_flush_kern_cache_louis)
213 ARM(	stmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
214 THUMB(	stmfd	sp!, {r4-r7, r9-r11, lr}	)
215	bl	v7_flush_dcache_louis
216	mov	r0, #0
217	ALT_SMP(mcr	p15, 0, r0, c7, c1, 0)	@ invalidate I-cache inner shareable
218	ALT_UP(mcr	p15, 0, r0, c7, c5, 0)	@ I+BTB cache invalidate
219 ARM(	ldmfd	sp!, {r4-r5, r7, r9-r11, lr}	)
220 THUMB(	ldmfd	sp!, {r4-r7, r9-r11, lr}	)
221	ret	lr
222ENDPROC(v7_flush_kern_cache_louis)
223
224/*
225 *	v7_flush_cache_all()
226 *
227 *	Flush all TLB entries in a particular address space
228 *
229 *	- mm    - mm_struct describing address space
230 */
231ENTRY(v7_flush_user_cache_all)
232	/*FALLTHROUGH*/
233
234/*
235 *	v7_flush_cache_range(start, end, flags)
236 *
237 *	Flush a range of TLB entries in the specified address space.
238 *
239 *	- start - start address (may not be aligned)
240 *	- end   - end address (exclusive, may not be aligned)
241 *	- flags	- vm_area_struct flags describing address space
242 *
243 *	It is assumed that:
244 *	- we have a VIPT cache.
245 */
246ENTRY(v7_flush_user_cache_range)
247	ret	lr
248ENDPROC(v7_flush_user_cache_all)
249ENDPROC(v7_flush_user_cache_range)
250
251/*
252 *	v7_coherent_kern_range(start,end)
253 *
254 *	Ensure that the I and D caches are coherent within specified
255 *	region.  This is typically used when code has been written to
256 *	a memory region, and will be executed.
257 *
258 *	- start   - virtual start address of region
259 *	- end     - virtual end address of region
260 *
261 *	It is assumed that:
262 *	- the Icache does not read data from the write buffer
263 */
264ENTRY(v7_coherent_kern_range)
265	/* FALLTHROUGH */
266
267/*
268 *	v7_coherent_user_range(start,end)
269 *
270 *	Ensure that the I and D caches are coherent within specified
271 *	region.  This is typically used when code has been written to
272 *	a memory region, and will be executed.
273 *
274 *	- start   - virtual start address of region
275 *	- end     - virtual end address of region
276 *
277 *	It is assumed that:
278 *	- the Icache does not read data from the write buffer
279 */
280ENTRY(v7_coherent_user_range)
281 UNWIND(.fnstart		)
282	dcache_line_size r2, r3
283	sub	r3, r2, #1
284	bic	r12, r0, r3
285#ifdef CONFIG_ARM_ERRATA_764369
286	ALT_SMP(W(dsb))
287	ALT_UP(W(nop))
288#endif
2891:
290 USER(	mcr	p15, 0, r12, c7, c11, 1	)	@ clean D line to the point of unification
291	add	r12, r12, r2
292	cmp	r12, r1
293	blo	1b
294	dsb	ishst
295#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
296	ldr	r3, =icache_size
297	ldr	r2, [r3, #0]
298#else
299	icache_line_size r2, r3
300#endif
301	sub	r3, r2, #1
302	bic	r12, r0, r3
3032:
304 USER(	mcr	p15, 0, r12, c7, c5, 1	)	@ invalidate I line
305	add	r12, r12, r2
306	cmp	r12, r1
307	blo	2b
308	mov	r0, #0
309	ALT_SMP(mcr	p15, 0, r0, c7, c1, 6)	@ invalidate BTB Inner Shareable
310	ALT_UP(mcr	p15, 0, r0, c7, c5, 6)	@ invalidate BTB
311	dsb	ishst
312	isb
313	ret	lr
314
315/*
316 * Fault handling for the cache operation above. If the virtual address in r0
317 * isn't mapped, fail with -EFAULT.
318 */
3199001:
320#ifdef CONFIG_ARM_ERRATA_775420
321	dsb
322#endif
323	mov	r0, #-EFAULT
324	ret	lr
325 UNWIND(.fnend		)
326ENDPROC(v7_coherent_kern_range)
327ENDPROC(v7_coherent_user_range)
328
329/*
330 *	v7_flush_kern_dcache_area(void *addr, size_t size)
331 *
332 *	Ensure that the data held in the page kaddr is written back
333 *	to the page in question.
334 *
335 *	- addr	- kernel address
336 *	- size	- region size
337 */
338ENTRY(v7_flush_kern_dcache_area)
339	dcache_line_size r2, r3
340	add	r1, r0, r1
341	sub	r3, r2, #1
342	bic	r0, r0, r3
343#ifdef CONFIG_ARM_ERRATA_764369
344	ALT_SMP(W(dsb))
345	ALT_UP(W(nop))
346#endif
3471:
348	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line / unified line
349	add	r0, r0, r2
350	cmp	r0, r1
351	blo	1b
352	dsb	st
353	ret	lr
354ENDPROC(v7_flush_kern_dcache_area)
355
356/*
357 *	v7_dma_inv_range(start,end)
358 *
359 *	Invalidate the data cache within the specified region; we will
360 *	be performing a DMA operation in this region and we want to
361 *	purge old data in the cache.
362 *
363 *	- start   - virtual start address of region
364 *	- end     - virtual end address of region
365 */
366v7_dma_inv_range:
367	dcache_line_size r2, r3
368	sub	r3, r2, #1
369	tst	r0, r3
370	bic	r0, r0, r3
371#ifdef CONFIG_ARM_ERRATA_764369
372	ALT_SMP(W(dsb))
373	ALT_UP(W(nop))
374#endif
375	mcrne	p15, 0, r0, c7, c14, 1		@ clean & invalidate D / U line
376	addne	r0, r0, r2
377
378	tst	r1, r3
379	bic	r1, r1, r3
380	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D / U line
381	cmp	r0, r1
3821:
383	mcrlo	p15, 0, r0, c7, c6, 1		@ invalidate D / U line
384	addlo	r0, r0, r2
385	cmplo	r0, r1
386	blo	1b
387	dsb	st
388	ret	lr
389ENDPROC(v7_dma_inv_range)
390
391/*
392 *	v7_dma_clean_range(start,end)
393 *	- start   - virtual start address of region
394 *	- end     - virtual end address of region
395 */
396v7_dma_clean_range:
397	dcache_line_size r2, r3
398	sub	r3, r2, #1
399	bic	r0, r0, r3
400#ifdef CONFIG_ARM_ERRATA_764369
401	ALT_SMP(W(dsb))
402	ALT_UP(W(nop))
403#endif
4041:
405	mcr	p15, 0, r0, c7, c10, 1		@ clean D / U line
406	add	r0, r0, r2
407	cmp	r0, r1
408	blo	1b
409	dsb	st
410	ret	lr
411ENDPROC(v7_dma_clean_range)
412
413/*
414 *	v7_dma_flush_range(start,end)
415 *	- start   - virtual start address of region
416 *	- end     - virtual end address of region
417 */
418ENTRY(v7_dma_flush_range)
419	dcache_line_size r2, r3
420	sub	r3, r2, #1
421	bic	r0, r0, r3
422#ifdef CONFIG_ARM_ERRATA_764369
423	ALT_SMP(W(dsb))
424	ALT_UP(W(nop))
425#endif
4261:
427	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D / U line
428	add	r0, r0, r2
429	cmp	r0, r1
430	blo	1b
431	dsb	st
432	ret	lr
433ENDPROC(v7_dma_flush_range)
434
435/*
436 *	dma_map_area(start, size, dir)
437 *	- start	- kernel virtual start address
438 *	- size	- size of region
439 *	- dir	- DMA direction
440 */
441ENTRY(v7_dma_map_area)
442	add	r1, r1, r0
443	teq	r2, #DMA_FROM_DEVICE
444	beq	v7_dma_inv_range
445	b	v7_dma_clean_range
446ENDPROC(v7_dma_map_area)
447
448/*
449 *	dma_unmap_area(start, size, dir)
450 *	- start	- kernel virtual start address
451 *	- size	- size of region
452 *	- dir	- DMA direction
453 */
454ENTRY(v7_dma_unmap_area)
455	add	r1, r1, r0
456	teq	r2, #DMA_TO_DEVICE
457	bne	v7_dma_inv_range
458	ret	lr
459ENDPROC(v7_dma_unmap_area)
460
461	__INITDATA
462
463	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
464	define_cache_functions v7
465
466	/* The Broadcom Brahma-B15 read-ahead cache requires some modifications
467	 * to the v7_cache_fns, we only override the ones we need
468	 */
469#ifndef CONFIG_CACHE_B15_RAC
470	globl_equ	b15_flush_kern_cache_all,	v7_flush_kern_cache_all
471#endif
472	globl_equ	b15_flush_icache_all,		v7_flush_icache_all
473	globl_equ	b15_flush_kern_cache_louis,	v7_flush_kern_cache_louis
474	globl_equ	b15_flush_user_cache_all,	v7_flush_user_cache_all
475	globl_equ	b15_flush_user_cache_range,	v7_flush_user_cache_range
476	globl_equ	b15_coherent_kern_range,	v7_coherent_kern_range
477	globl_equ	b15_coherent_user_range,	v7_coherent_user_range
478	globl_equ	b15_flush_kern_dcache_area,	v7_flush_kern_dcache_area
479
480	globl_equ	b15_dma_map_area,		v7_dma_map_area
481	globl_equ	b15_dma_unmap_area,		v7_dma_unmap_area
482	globl_equ	b15_dma_flush_range,		v7_dma_flush_range
483
484	define_cache_functions b15
485