xref: /openbmc/linux/arch/arm/mm/proc-xsc3.S (revision f21e49be) 
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * linux/arch/arm/mm/proc-xsc3.S
4 *
5 * Original Author: Matthew Gilbert
6 * Current Maintainer: Lennert Buytenhek <buytenh@wantstofly.org>
7 *
8 * Copyright 2004 (C) Intel Corp.
9 * Copyright 2005 (C) MontaVista Software, Inc.
10 *
11 * MMU functions for the Intel XScale3 Core (XSC3).  The XSC3 core is
12 * an extension to Intel's original XScale core that adds the following
13 * features:
14 *
15 * - ARMv6 Supersections
16 * - Low Locality Reference pages (replaces mini-cache)
17 * - 36-bit addressing
18 * - L2 cache
19 * - Cache coherency if chipset supports it
20 *
21 * Based on original XScale code by Nicolas Pitre.
22 */
23
24#include <linux/linkage.h>
25#include <linux/init.h>
26#include <linux/pgtable.h>
27#include <asm/assembler.h>
28#include <asm/hwcap.h>
29#include <asm/pgtable-hwdef.h>
30#include <asm/page.h>
31#include <asm/ptrace.h>
32#include "proc-macros.S"
33
34/*
35 * This is the maximum size of an area which will be flushed.  If the
36 * area is larger than this, then we flush the whole cache.
37 */
38#define MAX_AREA_SIZE	32768
39
40/*
41 * The cache line size of the L1 I, L1 D and unified L2 cache.
42 */
43#define CACHELINESIZE	32
44
45/*
46 * The size of the L1 D cache.
47 */
48#define CACHESIZE	32768
49
50/*
51 * This macro is used to wait for a CP15 write and is needed when we
52 * have to ensure that the last operation to the coprocessor was
53 * completed before continuing with operation.
54 */
55	.macro	cpwait_ret, lr, rd
56	mrc	p15, 0, \rd, c2, c0, 0		@ arbitrary read of cp15
57	sub	pc, \lr, \rd, LSR #32		@ wait for completion and
58						@ flush instruction pipeline
59	.endm
60
61/*
62 * This macro cleans and invalidates the entire L1 D cache.
63 */
64
65 	.macro  clean_d_cache rd, rs
66	mov	\rd, #0x1f00
67	orr	\rd, \rd, #0x00e0
681:	mcr	p15, 0, \rd, c7, c14, 2		@ clean/invalidate L1 D line
69	adds	\rd, \rd, #0x40000000
70	bcc	1b
71	subs	\rd, \rd, #0x20
72	bpl	1b
73	.endm
74
75	.text
76
77/*
78 * cpu_xsc3_proc_init()
79 *
80 * Nothing too exciting at the moment
81 */
82ENTRY(cpu_xsc3_proc_init)
83	ret	lr
84
85/*
86 * cpu_xsc3_proc_fin()
87 */
88ENTRY(cpu_xsc3_proc_fin)
89	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
90	bic	r0, r0, #0x1800			@ ...IZ...........
91	bic	r0, r0, #0x0006			@ .............CA.
92	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
93	ret	lr
94
95/*
96 * cpu_xsc3_reset(loc)
97 *
98 * Perform a soft reset of the system.  Put the CPU into the
99 * same state as it would be if it had been reset, and branch
100 * to what would be the reset vector.
101 *
102 * loc: location to jump to for soft reset
103 */
104	.align	5
105	.pushsection	.idmap.text, "ax"
106ENTRY(cpu_xsc3_reset)
107	mov	r1, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
108	msr	cpsr_c, r1			@ reset CPSR
109	mrc	p15, 0, r1, c1, c0, 0		@ ctrl register
110	bic	r1, r1, #0x3900			@ ..VIZ..S........
111	bic	r1, r1, #0x0086			@ ........B....CA.
112	mcr	p15, 0, r1, c1, c0, 0		@ ctrl register
113	mcr	p15, 0, ip, c7, c7, 0		@ invalidate L1 caches and BTB
114	bic	r1, r1, #0x0001			@ ...............M
115	mcr	p15, 0, r1, c1, c0, 0		@ ctrl register
116	@ CAUTION: MMU turned off from this point.  We count on the pipeline
117	@ already containing those two last instructions to survive.
118	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
119	ret	r0
120ENDPROC(cpu_xsc3_reset)
121	.popsection
122
123/*
124 * cpu_xsc3_do_idle()
125 *
126 * Cause the processor to idle
127 *
128 * For now we do nothing but go to idle mode for every case
129 *
130 * XScale supports clock switching, but using idle mode support
131 * allows external hardware to react to system state changes.
132 */
133	.align	5
134
135ENTRY(cpu_xsc3_do_idle)
136	mov	r0, #1
137	mcr	p14, 0, r0, c7, c0, 0		@ go to idle
138	ret	lr
139
140/* ================================= CACHE ================================ */
141
142/*
143 *	flush_icache_all()
144 *
145 *	Unconditionally clean and invalidate the entire icache.
146 */
147ENTRY(xsc3_flush_icache_all)
148	mov	r0, #0
149	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
150	ret	lr
151ENDPROC(xsc3_flush_icache_all)
152
153/*
154 *	flush_user_cache_all()
155 *
156 *	Invalidate all cache entries in a particular address
157 *	space.
158 */
159ENTRY(xsc3_flush_user_cache_all)
160	/* FALLTHROUGH */
161
162/*
163 *	flush_kern_cache_all()
164 *
165 *	Clean and invalidate the entire cache.
166 */
167ENTRY(xsc3_flush_kern_cache_all)
168	mov	r2, #VM_EXEC
169	mov	ip, #0
170__flush_whole_cache:
171	clean_d_cache r0, r1
172	tst	r2, #VM_EXEC
173	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate L1 I cache and BTB
174	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
175	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
176	ret	lr
177
178/*
179 *	flush_user_cache_range(start, end, vm_flags)
180 *
181 *	Invalidate a range of cache entries in the specified
182 *	address space.
183 *
184 *	- start - start address (may not be aligned)
185 *	- end	- end address (exclusive, may not be aligned)
186 *	- vma	- vma_area_struct describing address space
187 */
188	.align	5
189ENTRY(xsc3_flush_user_cache_range)
190	mov	ip, #0
191	sub	r3, r1, r0			@ calculate total size
192	cmp	r3, #MAX_AREA_SIZE
193	bhs	__flush_whole_cache
194
1951:	tst	r2, #VM_EXEC
196	mcrne	p15, 0, r0, c7, c5, 1		@ invalidate L1 I line
197	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
198	add	r0, r0, #CACHELINESIZE
199	cmp	r0, r1
200	blo	1b
201	tst	r2, #VM_EXEC
202	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
203	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
204	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
205	ret	lr
206
207/*
208 *	coherent_kern_range(start, end)
209 *
210 *	Ensure coherency between the I cache and the D cache in the
211 *	region described by start.  If you have non-snooping
212 *	Harvard caches, you need to implement this function.
213 *
214 *	- start  - virtual start address
215 *	- end	 - virtual end address
216 *
217 *	Note: single I-cache line invalidation isn't used here since
218 *	it also trashes the mini I-cache used by JTAG debuggers.
219 */
220ENTRY(xsc3_coherent_kern_range)
221/* FALLTHROUGH */
222ENTRY(xsc3_coherent_user_range)
223	bic	r0, r0, #CACHELINESIZE - 1
2241:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
225	add	r0, r0, #CACHELINESIZE
226	cmp	r0, r1
227	blo	1b
228	mov	r0, #0
229	mcr	p15, 0, r0, c7, c5, 0		@ invalidate L1 I cache and BTB
230	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
231	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
232	ret	lr
233
234/*
235 *	flush_kern_dcache_area(void *addr, size_t size)
236 *
237 *	Ensure no D cache aliasing occurs, either with itself or
238 *	the I cache.
239 *
240 *	- addr	- kernel address
241 *	- size	- region size
242 */
243ENTRY(xsc3_flush_kern_dcache_area)
244	add	r1, r0, r1
2451:	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
246	add	r0, r0, #CACHELINESIZE
247	cmp	r0, r1
248	blo	1b
249	mov	r0, #0
250	mcr	p15, 0, r0, c7, c5, 0		@ invalidate L1 I cache and BTB
251	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
252	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
253	ret	lr
254
255/*
256 *	dma_inv_range(start, end)
257 *
258 *	Invalidate (discard) the specified virtual address range.
259 *	May not write back any entries.  If 'start' or 'end'
260 *	are not cache line aligned, those lines must be written
261 *	back.
262 *
263 *	- start  - virtual start address
264 *	- end	 - virtual end address
265 */
266xsc3_dma_inv_range:
267	tst	r0, #CACHELINESIZE - 1
268	bic	r0, r0, #CACHELINESIZE - 1
269	mcrne	p15, 0, r0, c7, c10, 1		@ clean L1 D line
270	tst	r1, #CACHELINESIZE - 1
271	mcrne	p15, 0, r1, c7, c10, 1		@ clean L1 D line
2721:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate L1 D line
273	add	r0, r0, #CACHELINESIZE
274	cmp	r0, r1
275	blo	1b
276	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
277	ret	lr
278
279/*
280 *	dma_clean_range(start, end)
281 *
282 *	Clean the specified virtual address range.
283 *
284 *	- start  - virtual start address
285 *	- end	 - virtual end address
286 */
287xsc3_dma_clean_range:
288	bic	r0, r0, #CACHELINESIZE - 1
2891:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
290	add	r0, r0, #CACHELINESIZE
291	cmp	r0, r1
292	blo	1b
293	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
294	ret	lr
295
296/*
297 *	dma_flush_range(start, end)
298 *
299 *	Clean and invalidate the specified virtual address range.
300 *
301 *	- start  - virtual start address
302 *	- end	 - virtual end address
303 */
304ENTRY(xsc3_dma_flush_range)
305	bic	r0, r0, #CACHELINESIZE - 1
3061:	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
307	add	r0, r0, #CACHELINESIZE
308	cmp	r0, r1
309	blo	1b
310	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
311	ret	lr
312
313/*
314 *	dma_map_area(start, size, dir)
315 *	- start	- kernel virtual start address
316 *	- size	- size of region
317 *	- dir	- DMA direction
318 */
319ENTRY(xsc3_dma_map_area)
320	add	r1, r1, r0
321	cmp	r2, #DMA_TO_DEVICE
322	beq	xsc3_dma_clean_range
323	bcs	xsc3_dma_inv_range
324	b	xsc3_dma_flush_range
325ENDPROC(xsc3_dma_map_area)
326
327/*
328 *	dma_unmap_area(start, size, dir)
329 *	- start	- kernel virtual start address
330 *	- size	- size of region
331 *	- dir	- DMA direction
332 */
333ENTRY(xsc3_dma_unmap_area)
334	ret	lr
335ENDPROC(xsc3_dma_unmap_area)
336
337	.globl	xsc3_flush_kern_cache_louis
338	.equ	xsc3_flush_kern_cache_louis, xsc3_flush_kern_cache_all
339
340	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
341	define_cache_functions xsc3
342
343ENTRY(cpu_xsc3_dcache_clean_area)
3441:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
345	add	r0, r0, #CACHELINESIZE
346	subs	r1, r1, #CACHELINESIZE
347	bhi	1b
348	ret	lr
349
350/* =============================== PageTable ============================== */
351
352/*
353 * cpu_xsc3_switch_mm(pgd)
354 *
355 * Set the translation base pointer to be as described by pgd.
356 *
357 * pgd: new page tables
358 */
359	.align	5
360ENTRY(cpu_xsc3_switch_mm)
361	clean_d_cache r1, r2
362	mcr	p15, 0, ip, c7, c5, 0		@ invalidate L1 I cache and BTB
363	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
364	mcr	p15, 0, ip, c7, c5, 4		@ prefetch flush
365	orr	r0, r0, #0x18			@ cache the page table in L2
366	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
367	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
368	cpwait_ret lr, ip
369
370/*
371 * cpu_xsc3_set_pte_ext(ptep, pte, ext)
372 *
373 * Set a PTE and flush it out
374 */
375cpu_xsc3_mt_table:
376	.long	0x00						@ L_PTE_MT_UNCACHED
377	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_BUFFERABLE
378	.long	PTE_EXT_TEX(5) | PTE_CACHEABLE			@ L_PTE_MT_WRITETHROUGH
379	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_WRITEBACK
380	.long	PTE_EXT_TEX(1) | PTE_BUFFERABLE			@ L_PTE_MT_DEV_SHARED
381	.long	0x00						@ unused
382	.long	0x00						@ L_PTE_MT_MINICACHE (not present)
383	.long	PTE_EXT_TEX(5) | PTE_CACHEABLE | PTE_BUFFERABLE	@ L_PTE_MT_WRITEALLOC (not present?)
384	.long	0x00						@ unused
385	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_DEV_WC
386	.long	0x00						@ unused
387	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_DEV_CACHED
388	.long	PTE_EXT_TEX(2)					@ L_PTE_MT_DEV_NONSHARED
389	.long	0x00						@ unused
390	.long	0x00						@ unused
391	.long	0x00						@ unused
392
393	.align	5
394ENTRY(cpu_xsc3_set_pte_ext)
395	xscale_set_pte_ext_prologue
396
397	tst	r1, #L_PTE_SHARED		@ shared?
398	and	r1, r1, #L_PTE_MT_MASK
399	adr	ip, cpu_xsc3_mt_table
400	ldr	ip, [ip, r1]
401	orrne	r2, r2, #PTE_EXT_COHERENT	@ interlock: mask in coherent bit
402	bic	r2, r2, #0x0c			@ clear old C,B bits
403	orr	r2, r2, ip
404
405	xscale_set_pte_ext_epilogue
406	ret	lr
407
408	.ltorg
409	.align
410
411.globl	cpu_xsc3_suspend_size
412.equ	cpu_xsc3_suspend_size, 4 * 6
413#ifdef CONFIG_ARM_CPU_SUSPEND
414ENTRY(cpu_xsc3_do_suspend)
415	stmfd	sp!, {r4 - r9, lr}
416	mrc	p14, 0, r4, c6, c0, 0	@ clock configuration, for turbo mode
417	mrc	p15, 0, r5, c15, c1, 0	@ CP access reg
418	mrc	p15, 0, r6, c13, c0, 0	@ PID
419	mrc 	p15, 0, r7, c3, c0, 0	@ domain ID
420	mrc	p15, 0, r8, c1, c0, 1	@ auxiliary control reg
421	mrc 	p15, 0, r9, c1, c0, 0	@ control reg
422	bic	r4, r4, #2		@ clear frequency change bit
423	stmia	r0, {r4 - r9}		@ store cp regs
424	ldmia	sp!, {r4 - r9, pc}
425ENDPROC(cpu_xsc3_do_suspend)
426
427ENTRY(cpu_xsc3_do_resume)
428	ldmia	r0, {r4 - r9}		@ load cp regs
429	mov	ip, #0
430	mcr	p15, 0, ip, c7, c7, 0	@ invalidate I & D caches, BTB
431	mcr	p15, 0, ip, c7, c10, 4	@ drain write (&fill) buffer
432	mcr	p15, 0, ip, c7, c5, 4	@ flush prefetch buffer
433	mcr	p15, 0, ip, c8, c7, 0	@ invalidate I & D TLBs
434	mcr	p14, 0, r4, c6, c0, 0	@ clock configuration, turbo mode.
435	mcr	p15, 0, r5, c15, c1, 0	@ CP access reg
436	mcr	p15, 0, r6, c13, c0, 0	@ PID
437	mcr	p15, 0, r7, c3, c0, 0	@ domain ID
438	orr	r1, r1, #0x18		@ cache the page table in L2
439	mcr	p15, 0, r1, c2, c0, 0	@ translation table base addr
440	mcr	p15, 0, r8, c1, c0, 1	@ auxiliary control reg
441	mov	r0, r9			@ control register
442	b	cpu_resume_mmu
443ENDPROC(cpu_xsc3_do_resume)
444#endif
445
446	.type	__xsc3_setup, #function
447__xsc3_setup:
448	mov	r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
449	msr	cpsr_c, r0
450	mcr	p15, 0, ip, c7, c7, 0		@ invalidate L1 caches and BTB
451	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
452	mcr	p15, 0, ip, c7, c5, 4		@ prefetch flush
453	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
454	orr	r4, r4, #0x18			@ cache the page table in L2
455	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer
456
457	mov	r0, #1 << 6			@ cp6 access for early sched_clock
458	mcr	p15, 0, r0, c15, c1, 0		@ write CP access register
459
460	mrc	p15, 0, r0, c1, c0, 1		@ get auxiliary control reg
461	and	r0, r0, #2			@ preserve bit P bit setting
462	orr	r0, r0, #(1 << 10)		@ enable L2 for LLR cache
463	mcr	p15, 0, r0, c1, c0, 1		@ set auxiliary control reg
464
465	adr	r5, xsc3_crval
466	ldmia	r5, {r5, r6}
467
468#ifdef CONFIG_CACHE_XSC3L2
469	mrc	p15, 1, r0, c0, c0, 1		@ get L2 present information
470	ands	r0, r0, #0xf8
471	orrne	r6, r6, #(1 << 26)		@ enable L2 if present
472#endif
473
474	mrc	p15, 0, r0, c1, c0, 0		@ get control register
475	bic	r0, r0, r5			@ ..V. ..R. .... ..A.
476	orr	r0, r0, r6			@ ..VI Z..S .... .C.M (mmu)
477						@ ...I Z..S .... .... (uc)
478	ret	lr
479
480	.size	__xsc3_setup, . - __xsc3_setup
481
482	.type	xsc3_crval, #object
483xsc3_crval:
484	crval	clear=0x04002202, mmuset=0x00003905, ucset=0x00001900
485
486	__INITDATA
487
488	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
489	define_processor_functions xsc3, dabort=v5t_early_abort, pabort=legacy_pabort, suspend=1
490
491	.section ".rodata"
492
493	string	cpu_arch_name, "armv5te"
494	string	cpu_elf_name, "v5"
495	string	cpu_xsc3_name, "XScale-V3 based processor"
496
497	.align
498
499	.section ".proc.info.init", "a"
500
501.macro xsc3_proc_info name:req, cpu_val:req, cpu_mask:req
502	.type	__\name\()_proc_info,#object
503__\name\()_proc_info:
504	.long	\cpu_val
505	.long	\cpu_mask
506	.long	PMD_TYPE_SECT | \
507		PMD_SECT_BUFFERABLE | \
508		PMD_SECT_CACHEABLE | \
509		PMD_SECT_AP_WRITE | \
510		PMD_SECT_AP_READ
511	.long	PMD_TYPE_SECT | \
512		PMD_SECT_AP_WRITE | \
513		PMD_SECT_AP_READ
514	initfn	__xsc3_setup, __\name\()_proc_info
515	.long	cpu_arch_name
516	.long	cpu_elf_name
517	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
518	.long	cpu_xsc3_name
519	.long	xsc3_processor_functions
520	.long	v4wbi_tlb_fns
521	.long	xsc3_mc_user_fns
522	.long	xsc3_cache_fns
523	.size	__\name\()_proc_info, . - __\name\()_proc_info
524.endm
525
526	xsc3_proc_info xsc3, 0x69056000, 0xffffe000
527
528/* Note: PXA935 changed its implementor ID from Intel to Marvell */
529	xsc3_proc_info xsc3_pxa935, 0x56056000, 0xffffe000
530