xref: /openbmc/linux/arch/arm/mm/proc-xsc3.S (revision 7dd65feb)
1/*
2 * linux/arch/arm/mm/proc-xsc3.S
3 *
4 * Original Author: Matthew Gilbert
5 * Current Maintainer: Lennert Buytenhek <buytenh@wantstofly.org>
6 *
7 * Copyright 2004 (C) Intel Corp.
8 * Copyright 2005 (C) MontaVista Software, Inc.
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 * MMU functions for the Intel XScale3 Core (XSC3).  The XSC3 core is
15 * an extension to Intel's original XScale core that adds the following
16 * features:
17 *
18 * - ARMv6 Supersections
19 * - Low Locality Reference pages (replaces mini-cache)
20 * - 36-bit addressing
21 * - L2 cache
22 * - Cache coherency if chipset supports it
23 *
24 * Based on original XScale code by Nicolas Pitre.
25 */
26
27#include <linux/linkage.h>
28#include <linux/init.h>
29#include <asm/assembler.h>
30#include <asm/hwcap.h>
31#include <mach/hardware.h>
32#include <asm/pgtable.h>
33#include <asm/pgtable-hwdef.h>
34#include <asm/page.h>
35#include <asm/ptrace.h>
36#include "proc-macros.S"
37
38/*
39 * This is the maximum size of an area which will be flushed.  If the
40 * area is larger than this, then we flush the whole cache.
41 */
42#define MAX_AREA_SIZE	32768
43
44/*
45 * The cache line size of the L1 I, L1 D and unified L2 cache.
46 */
47#define CACHELINESIZE	32
48
49/*
50 * The size of the L1 D cache.
51 */
52#define CACHESIZE	32768
53
54/*
55 * This macro is used to wait for a CP15 write and is needed when we
56 * have to ensure that the last operation to the coprocessor was
57 * completed before continuing with operation.
58 */
59	.macro	cpwait_ret, lr, rd
60	mrc	p15, 0, \rd, c2, c0, 0		@ arbitrary read of cp15
61	sub	pc, \lr, \rd, LSR #32		@ wait for completion and
62						@ flush instruction pipeline
63	.endm
64
65/*
66 * This macro cleans and invalidates the entire L1 D cache.
67 */
68
69 	.macro  clean_d_cache rd, rs
70	mov	\rd, #0x1f00
71	orr	\rd, \rd, #0x00e0
721:	mcr	p15, 0, \rd, c7, c14, 2		@ clean/invalidate L1 D line
73	adds	\rd, \rd, #0x40000000
74	bcc	1b
75	subs	\rd, \rd, #0x20
76	bpl	1b
77	.endm
78
79	.text
80
81/*
82 * cpu_xsc3_proc_init()
83 *
84 * Nothing too exciting at the moment
85 */
86ENTRY(cpu_xsc3_proc_init)
87	mov	pc, lr
88
89/*
90 * cpu_xsc3_proc_fin()
91 */
92ENTRY(cpu_xsc3_proc_fin)
93	str	lr, [sp, #-4]!
94	mov	r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
95	msr	cpsr_c, r0
96	bl	xsc3_flush_kern_cache_all	@ clean caches
97	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
98	bic	r0, r0, #0x1800			@ ...IZ...........
99	bic	r0, r0, #0x0006			@ .............CA.
100	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
101	ldr	pc, [sp], #4
102
103/*
104 * cpu_xsc3_reset(loc)
105 *
106 * Perform a soft reset of the system.  Put the CPU into the
107 * same state as it would be if it had been reset, and branch
108 * to what would be the reset vector.
109 *
110 * loc: location to jump to for soft reset
111 */
112	.align	5
113ENTRY(cpu_xsc3_reset)
114	mov	r1, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
115	msr	cpsr_c, r1			@ reset CPSR
116	mrc	p15, 0, r1, c1, c0, 0		@ ctrl register
117	bic	r1, r1, #0x3900			@ ..VIZ..S........
118	bic	r1, r1, #0x0086			@ ........B....CA.
119	mcr	p15, 0, r1, c1, c0, 0		@ ctrl register
120	mcr	p15, 0, ip, c7, c7, 0		@ invalidate L1 caches and BTB
121	bic	r1, r1, #0x0001			@ ...............M
122	mcr	p15, 0, r1, c1, c0, 0		@ ctrl register
123	@ CAUTION: MMU turned off from this point.  We count on the pipeline
124	@ already containing those two last instructions to survive.
125	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
126	mov	pc, r0
127
128/*
129 * cpu_xsc3_do_idle()
130 *
131 * Cause the processor to idle
132 *
133 * For now we do nothing but go to idle mode for every case
134 *
135 * XScale supports clock switching, but using idle mode support
136 * allows external hardware to react to system state changes.
137 */
138	.align	5
139
140ENTRY(cpu_xsc3_do_idle)
141	mov	r0, #1
142	mcr	p14, 0, r0, c7, c0, 0		@ go to idle
143	mov	pc, lr
144
145/* ================================= CACHE ================================ */
146
147/*
148 *	flush_user_cache_all()
149 *
150 *	Invalidate all cache entries in a particular address
151 *	space.
152 */
153ENTRY(xsc3_flush_user_cache_all)
154	/* FALLTHROUGH */
155
156/*
157 *	flush_kern_cache_all()
158 *
159 *	Clean and invalidate the entire cache.
160 */
161ENTRY(xsc3_flush_kern_cache_all)
162	mov	r2, #VM_EXEC
163	mov	ip, #0
164__flush_whole_cache:
165	clean_d_cache r0, r1
166	tst	r2, #VM_EXEC
167	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate L1 I cache and BTB
168	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
169	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
170	mov	pc, lr
171
172/*
173 *	flush_user_cache_range(start, end, vm_flags)
174 *
175 *	Invalidate a range of cache entries in the specified
176 *	address space.
177 *
178 *	- start - start address (may not be aligned)
179 *	- end	- end address (exclusive, may not be aligned)
180 *	- vma	- vma_area_struct describing address space
181 */
182	.align	5
183ENTRY(xsc3_flush_user_cache_range)
184	mov	ip, #0
185	sub	r3, r1, r0			@ calculate total size
186	cmp	r3, #MAX_AREA_SIZE
187	bhs	__flush_whole_cache
188
1891:	tst	r2, #VM_EXEC
190	mcrne	p15, 0, r0, c7, c5, 1		@ invalidate L1 I line
191	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
192	add	r0, r0, #CACHELINESIZE
193	cmp	r0, r1
194	blo	1b
195	tst	r2, #VM_EXEC
196	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
197	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
198	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
199	mov	pc, lr
200
201/*
202 *	coherent_kern_range(start, end)
203 *
204 *	Ensure coherency between the I cache and the D cache in the
205 *	region described by start.  If you have non-snooping
206 *	Harvard caches, you need to implement this function.
207 *
208 *	- start  - virtual start address
209 *	- end	 - virtual end address
210 *
211 *	Note: single I-cache line invalidation isn't used here since
212 *	it also trashes the mini I-cache used by JTAG debuggers.
213 */
214ENTRY(xsc3_coherent_kern_range)
215/* FALLTHROUGH */
216ENTRY(xsc3_coherent_user_range)
217	bic	r0, r0, #CACHELINESIZE - 1
2181:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
219	add	r0, r0, #CACHELINESIZE
220	cmp	r0, r1
221	blo	1b
222	mov	r0, #0
223	mcr	p15, 0, r0, c7, c5, 0		@ invalidate L1 I cache and BTB
224	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
225	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
226	mov	pc, lr
227
228/*
229 *	flush_kern_dcache_area(void *addr, size_t size)
230 *
231 *	Ensure no D cache aliasing occurs, either with itself or
232 *	the I cache.
233 *
234 *	- addr	- kernel address
235 *	- size	- region size
236 */
237ENTRY(xsc3_flush_kern_dcache_area)
238	add	r1, r0, r1
2391:	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
240	add	r0, r0, #CACHELINESIZE
241	cmp	r0, r1
242	blo	1b
243	mov	r0, #0
244	mcr	p15, 0, r0, c7, c5, 0		@ invalidate L1 I cache and BTB
245	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
246	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
247	mov	pc, lr
248
249/*
250 *	dma_inv_range(start, end)
251 *
252 *	Invalidate (discard) the specified virtual address range.
253 *	May not write back any entries.  If 'start' or 'end'
254 *	are not cache line aligned, those lines must be written
255 *	back.
256 *
257 *	- start  - virtual start address
258 *	- end	 - virtual end address
259 */
260ENTRY(xsc3_dma_inv_range)
261	tst	r0, #CACHELINESIZE - 1
262	bic	r0, r0, #CACHELINESIZE - 1
263	mcrne	p15, 0, r0, c7, c10, 1		@ clean L1 D line
264	tst	r1, #CACHELINESIZE - 1
265	mcrne	p15, 0, r1, c7, c10, 1		@ clean L1 D line
2661:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate L1 D line
267	add	r0, r0, #CACHELINESIZE
268	cmp	r0, r1
269	blo	1b
270	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
271	mov	pc, lr
272
273/*
274 *	dma_clean_range(start, end)
275 *
276 *	Clean the specified virtual address range.
277 *
278 *	- start  - virtual start address
279 *	- end	 - virtual end address
280 */
281ENTRY(xsc3_dma_clean_range)
282	bic	r0, r0, #CACHELINESIZE - 1
2831:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
284	add	r0, r0, #CACHELINESIZE
285	cmp	r0, r1
286	blo	1b
287	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
288	mov	pc, lr
289
290/*
291 *	dma_flush_range(start, end)
292 *
293 *	Clean and invalidate the specified virtual address range.
294 *
295 *	- start  - virtual start address
296 *	- end	 - virtual end address
297 */
298ENTRY(xsc3_dma_flush_range)
299	bic	r0, r0, #CACHELINESIZE - 1
3001:	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
301	add	r0, r0, #CACHELINESIZE
302	cmp	r0, r1
303	blo	1b
304	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
305	mov	pc, lr
306
307ENTRY(xsc3_cache_fns)
308	.long	xsc3_flush_kern_cache_all
309	.long	xsc3_flush_user_cache_all
310	.long	xsc3_flush_user_cache_range
311	.long	xsc3_coherent_kern_range
312	.long	xsc3_coherent_user_range
313	.long	xsc3_flush_kern_dcache_area
314	.long	xsc3_dma_inv_range
315	.long	xsc3_dma_clean_range
316	.long	xsc3_dma_flush_range
317
318ENTRY(cpu_xsc3_dcache_clean_area)
3191:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
320	add	r0, r0, #CACHELINESIZE
321	subs	r1, r1, #CACHELINESIZE
322	bhi	1b
323	mov	pc, lr
324
325/* =============================== PageTable ============================== */
326
327/*
328 * cpu_xsc3_switch_mm(pgd)
329 *
330 * Set the translation base pointer to be as described by pgd.
331 *
332 * pgd: new page tables
333 */
334	.align	5
335ENTRY(cpu_xsc3_switch_mm)
336	clean_d_cache r1, r2
337	mcr	p15, 0, ip, c7, c5, 0		@ invalidate L1 I cache and BTB
338	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
339	mcr	p15, 0, ip, c7, c5, 4		@ prefetch flush
340	orr	r0, r0, #0x18			@ cache the page table in L2
341	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
342	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
343	cpwait_ret lr, ip
344
345/*
346 * cpu_xsc3_set_pte_ext(ptep, pte, ext)
347 *
348 * Set a PTE and flush it out
349 */
350cpu_xsc3_mt_table:
351	.long	0x00						@ L_PTE_MT_UNCACHED
352	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_BUFFERABLE
353	.long	PTE_EXT_TEX(5) | PTE_CACHEABLE			@ L_PTE_MT_WRITETHROUGH
354	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_WRITEBACK
355	.long	PTE_EXT_TEX(1) | PTE_BUFFERABLE			@ L_PTE_MT_DEV_SHARED
356	.long	0x00						@ unused
357	.long	0x00						@ L_PTE_MT_MINICACHE (not present)
358	.long	PTE_EXT_TEX(5) | PTE_CACHEABLE | PTE_BUFFERABLE	@ L_PTE_MT_WRITEALLOC (not present?)
359	.long	0x00						@ unused
360	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_DEV_WC
361	.long	0x00						@ unused
362	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_DEV_CACHED
363	.long	PTE_EXT_TEX(2)					@ L_PTE_MT_DEV_NONSHARED
364	.long	0x00						@ unused
365	.long	0x00						@ unused
366	.long	0x00						@ unused
367
368	.align	5
369ENTRY(cpu_xsc3_set_pte_ext)
370	xscale_set_pte_ext_prologue
371
372	tst	r1, #L_PTE_SHARED		@ shared?
373	and	r1, r1, #L_PTE_MT_MASK
374	adr	ip, cpu_xsc3_mt_table
375	ldr	ip, [ip, r1]
376	orrne	r2, r2, #PTE_EXT_COHERENT	@ interlock: mask in coherent bit
377	bic	r2, r2, #0x0c			@ clear old C,B bits
378	orr	r2, r2, ip
379
380	xscale_set_pte_ext_epilogue
381	mov	pc, lr
382
383	.ltorg
384
385	.align
386
387	__INIT
388
389	.type	__xsc3_setup, #function
390__xsc3_setup:
391	mov	r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
392	msr	cpsr_c, r0
393	mcr	p15, 0, ip, c7, c7, 0		@ invalidate L1 caches and BTB
394	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
395	mcr	p15, 0, ip, c7, c5, 4		@ prefetch flush
396	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
397	orr	r4, r4, #0x18			@ cache the page table in L2
398	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer
399
400	mov	r0, #1 << 6			@ cp6 access for early sched_clock
401	mcr	p15, 0, r0, c15, c1, 0		@ write CP access register
402
403	mrc	p15, 0, r0, c1, c0, 1		@ get auxiliary control reg
404	and	r0, r0, #2			@ preserve bit P bit setting
405	orr	r0, r0, #(1 << 10)		@ enable L2 for LLR cache
406	mcr	p15, 0, r0, c1, c0, 1		@ set auxiliary control reg
407
408	adr	r5, xsc3_crval
409	ldmia	r5, {r5, r6}
410	mrc	p15, 0, r0, c1, c0, 0		@ get control register
411	bic	r0, r0, r5			@ ..V. ..R. .... ..A.
412	orr	r0, r0, r6			@ ..VI Z..S .... .C.M (mmu)
413						@ ...I Z..S .... .... (uc)
414	mov	pc, lr
415
416	.size	__xsc3_setup, . - __xsc3_setup
417
418	.type	xsc3_crval, #object
419xsc3_crval:
420	crval	clear=0x04002202, mmuset=0x00003905, ucset=0x00001900
421
422	__INITDATA
423
424/*
425 * Purpose : Function pointers used to access above functions - all calls
426 *	     come through these
427 */
428
429	.type	xsc3_processor_functions, #object
430ENTRY(xsc3_processor_functions)
431	.word	v5t_early_abort
432	.word	legacy_pabort
433	.word	cpu_xsc3_proc_init
434	.word	cpu_xsc3_proc_fin
435	.word	cpu_xsc3_reset
436	.word	cpu_xsc3_do_idle
437	.word	cpu_xsc3_dcache_clean_area
438	.word	cpu_xsc3_switch_mm
439	.word	cpu_xsc3_set_pte_ext
440	.size	xsc3_processor_functions, . - xsc3_processor_functions
441
442	.section ".rodata"
443
444	.type	cpu_arch_name, #object
445cpu_arch_name:
446	.asciz	"armv5te"
447	.size	cpu_arch_name, . - cpu_arch_name
448
449	.type	cpu_elf_name, #object
450cpu_elf_name:
451	.asciz	"v5"
452	.size	cpu_elf_name, . - cpu_elf_name
453
454	.type	cpu_xsc3_name, #object
455cpu_xsc3_name:
456	.asciz	"XScale-V3 based processor"
457	.size	cpu_xsc3_name, . - cpu_xsc3_name
458
459	.align
460
461	.section ".proc.info.init", #alloc, #execinstr
462
463	.type	__xsc3_proc_info,#object
464__xsc3_proc_info:
465	.long	0x69056000
466	.long	0xffffe000
467	.long	PMD_TYPE_SECT | \
468		PMD_SECT_BUFFERABLE | \
469		PMD_SECT_CACHEABLE | \
470		PMD_SECT_AP_WRITE | \
471		PMD_SECT_AP_READ
472	.long	PMD_TYPE_SECT | \
473		PMD_SECT_AP_WRITE | \
474		PMD_SECT_AP_READ
475	b	__xsc3_setup
476	.long	cpu_arch_name
477	.long	cpu_elf_name
478	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
479	.long	cpu_xsc3_name
480	.long	xsc3_processor_functions
481	.long	v4wbi_tlb_fns
482	.long	xsc3_mc_user_fns
483	.long	xsc3_cache_fns
484	.size	__xsc3_proc_info, . - __xsc3_proc_info
485
486/* Note: PXA935 changed its implementor ID from Intel to Marvell */
487
488	.type	__xsc3_pxa935_proc_info,#object
489__xsc3_pxa935_proc_info:
490	.long	0x56056000
491	.long	0xffffe000
492	.long	PMD_TYPE_SECT | \
493		PMD_SECT_BUFFERABLE | \
494		PMD_SECT_CACHEABLE | \
495		PMD_SECT_AP_WRITE | \
496		PMD_SECT_AP_READ
497	.long	PMD_TYPE_SECT | \
498		PMD_SECT_AP_WRITE | \
499		PMD_SECT_AP_READ
500	b	__xsc3_setup
501	.long	cpu_arch_name
502	.long	cpu_elf_name
503	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
504	.long	cpu_xsc3_name
505	.long	xsc3_processor_functions
506	.long	v4wbi_tlb_fns
507	.long	xsc3_mc_user_fns
508	.long	xsc3_cache_fns
509	.size	__xsc3_pxa935_proc_info, . - __xsc3_pxa935_proc_info
510