xref: /openbmc/linux/arch/arm/mm/proc-xsc3.S (revision 5085f3ff)
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	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
94	bic	r0, r0, #0x1800			@ ...IZ...........
95	bic	r0, r0, #0x0006			@ .............CA.
96	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
97	mov	pc, lr
98
99/*
100 * cpu_xsc3_reset(loc)
101 *
102 * Perform a soft reset of the system.  Put the CPU into the
103 * same state as it would be if it had been reset, and branch
104 * to what would be the reset vector.
105 *
106 * loc: location to jump to for soft reset
107 */
108	.align	5
109ENTRY(cpu_xsc3_reset)
110	mov	r1, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
111	msr	cpsr_c, r1			@ reset CPSR
112	mrc	p15, 0, r1, c1, c0, 0		@ ctrl register
113	bic	r1, r1, #0x3900			@ ..VIZ..S........
114	bic	r1, r1, #0x0086			@ ........B....CA.
115	mcr	p15, 0, r1, c1, c0, 0		@ ctrl register
116	mcr	p15, 0, ip, c7, c7, 0		@ invalidate L1 caches and BTB
117	bic	r1, r1, #0x0001			@ ...............M
118	mcr	p15, 0, r1, c1, c0, 0		@ ctrl register
119	@ CAUTION: MMU turned off from this point.  We count on the pipeline
120	@ already containing those two last instructions to survive.
121	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
122	mov	pc, r0
123
124/*
125 * cpu_xsc3_do_idle()
126 *
127 * Cause the processor to idle
128 *
129 * For now we do nothing but go to idle mode for every case
130 *
131 * XScale supports clock switching, but using idle mode support
132 * allows external hardware to react to system state changes.
133 */
134	.align	5
135
136ENTRY(cpu_xsc3_do_idle)
137	mov	r0, #1
138	mcr	p14, 0, r0, c7, c0, 0		@ go to idle
139	mov	pc, lr
140
141/* ================================= CACHE ================================ */
142
143/*
144 *	flush_user_cache_all()
145 *
146 *	Invalidate all cache entries in a particular address
147 *	space.
148 */
149ENTRY(xsc3_flush_user_cache_all)
150	/* FALLTHROUGH */
151
152/*
153 *	flush_kern_cache_all()
154 *
155 *	Clean and invalidate the entire cache.
156 */
157ENTRY(xsc3_flush_kern_cache_all)
158	mov	r2, #VM_EXEC
159	mov	ip, #0
160__flush_whole_cache:
161	clean_d_cache r0, r1
162	tst	r2, #VM_EXEC
163	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate L1 I cache and BTB
164	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
165	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
166	mov	pc, lr
167
168/*
169 *	flush_user_cache_range(start, end, vm_flags)
170 *
171 *	Invalidate a range of cache entries in the specified
172 *	address space.
173 *
174 *	- start - start address (may not be aligned)
175 *	- end	- end address (exclusive, may not be aligned)
176 *	- vma	- vma_area_struct describing address space
177 */
178	.align	5
179ENTRY(xsc3_flush_user_cache_range)
180	mov	ip, #0
181	sub	r3, r1, r0			@ calculate total size
182	cmp	r3, #MAX_AREA_SIZE
183	bhs	__flush_whole_cache
184
1851:	tst	r2, #VM_EXEC
186	mcrne	p15, 0, r0, c7, c5, 1		@ invalidate L1 I line
187	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
188	add	r0, r0, #CACHELINESIZE
189	cmp	r0, r1
190	blo	1b
191	tst	r2, #VM_EXEC
192	mcrne	p15, 0, ip, c7, c5, 6		@ invalidate BTB
193	mcrne	p15, 0, ip, c7, c10, 4		@ data write barrier
194	mcrne	p15, 0, ip, c7, c5, 4		@ prefetch flush
195	mov	pc, lr
196
197/*
198 *	coherent_kern_range(start, end)
199 *
200 *	Ensure coherency between the I cache and the D cache in the
201 *	region described by start.  If you have non-snooping
202 *	Harvard caches, you need to implement this function.
203 *
204 *	- start  - virtual start address
205 *	- end	 - virtual end address
206 *
207 *	Note: single I-cache line invalidation isn't used here since
208 *	it also trashes the mini I-cache used by JTAG debuggers.
209 */
210ENTRY(xsc3_coherent_kern_range)
211/* FALLTHROUGH */
212ENTRY(xsc3_coherent_user_range)
213	bic	r0, r0, #CACHELINESIZE - 1
2141:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
215	add	r0, r0, #CACHELINESIZE
216	cmp	r0, r1
217	blo	1b
218	mov	r0, #0
219	mcr	p15, 0, r0, c7, c5, 0		@ invalidate L1 I cache and BTB
220	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
221	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
222	mov	pc, lr
223
224/*
225 *	flush_kern_dcache_area(void *addr, size_t size)
226 *
227 *	Ensure no D cache aliasing occurs, either with itself or
228 *	the I cache.
229 *
230 *	- addr	- kernel address
231 *	- size	- region size
232 */
233ENTRY(xsc3_flush_kern_dcache_area)
234	add	r1, r0, r1
2351:	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
236	add	r0, r0, #CACHELINESIZE
237	cmp	r0, r1
238	blo	1b
239	mov	r0, #0
240	mcr	p15, 0, r0, c7, c5, 0		@ invalidate L1 I cache and BTB
241	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
242	mcr	p15, 0, r0, c7, c5, 4		@ prefetch flush
243	mov	pc, lr
244
245/*
246 *	dma_inv_range(start, end)
247 *
248 *	Invalidate (discard) the specified virtual address range.
249 *	May not write back any entries.  If 'start' or 'end'
250 *	are not cache line aligned, those lines must be written
251 *	back.
252 *
253 *	- start  - virtual start address
254 *	- end	 - virtual end address
255 */
256xsc3_dma_inv_range:
257	tst	r0, #CACHELINESIZE - 1
258	bic	r0, r0, #CACHELINESIZE - 1
259	mcrne	p15, 0, r0, c7, c10, 1		@ clean L1 D line
260	tst	r1, #CACHELINESIZE - 1
261	mcrne	p15, 0, r1, c7, c10, 1		@ clean L1 D line
2621:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate L1 D line
263	add	r0, r0, #CACHELINESIZE
264	cmp	r0, r1
265	blo	1b
266	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
267	mov	pc, lr
268
269/*
270 *	dma_clean_range(start, end)
271 *
272 *	Clean the specified virtual address range.
273 *
274 *	- start  - virtual start address
275 *	- end	 - virtual end address
276 */
277xsc3_dma_clean_range:
278	bic	r0, r0, #CACHELINESIZE - 1
2791:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
280	add	r0, r0, #CACHELINESIZE
281	cmp	r0, r1
282	blo	1b
283	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
284	mov	pc, lr
285
286/*
287 *	dma_flush_range(start, end)
288 *
289 *	Clean and invalidate the specified virtual address range.
290 *
291 *	- start  - virtual start address
292 *	- end	 - virtual end address
293 */
294ENTRY(xsc3_dma_flush_range)
295	bic	r0, r0, #CACHELINESIZE - 1
2961:	mcr	p15, 0, r0, c7, c14, 1		@ clean/invalidate L1 D line
297	add	r0, r0, #CACHELINESIZE
298	cmp	r0, r1
299	blo	1b
300	mcr	p15, 0, r0, c7, c10, 4		@ data write barrier
301	mov	pc, lr
302
303/*
304 *	dma_map_area(start, size, dir)
305 *	- start	- kernel virtual start address
306 *	- size	- size of region
307 *	- dir	- DMA direction
308 */
309ENTRY(xsc3_dma_map_area)
310	add	r1, r1, r0
311	cmp	r2, #DMA_TO_DEVICE
312	beq	xsc3_dma_clean_range
313	bcs	xsc3_dma_inv_range
314	b	xsc3_dma_flush_range
315ENDPROC(xsc3_dma_map_area)
316
317/*
318 *	dma_unmap_area(start, size, dir)
319 *	- start	- kernel virtual start address
320 *	- size	- size of region
321 *	- dir	- DMA direction
322 */
323ENTRY(xsc3_dma_unmap_area)
324	mov	pc, lr
325ENDPROC(xsc3_dma_unmap_area)
326
327ENTRY(xsc3_cache_fns)
328	.long	xsc3_flush_kern_cache_all
329	.long	xsc3_flush_user_cache_all
330	.long	xsc3_flush_user_cache_range
331	.long	xsc3_coherent_kern_range
332	.long	xsc3_coherent_user_range
333	.long	xsc3_flush_kern_dcache_area
334	.long	xsc3_dma_map_area
335	.long	xsc3_dma_unmap_area
336	.long	xsc3_dma_flush_range
337
338ENTRY(cpu_xsc3_dcache_clean_area)
3391:	mcr	p15, 0, r0, c7, c10, 1		@ clean L1 D line
340	add	r0, r0, #CACHELINESIZE
341	subs	r1, r1, #CACHELINESIZE
342	bhi	1b
343	mov	pc, lr
344
345/* =============================== PageTable ============================== */
346
347/*
348 * cpu_xsc3_switch_mm(pgd)
349 *
350 * Set the translation base pointer to be as described by pgd.
351 *
352 * pgd: new page tables
353 */
354	.align	5
355ENTRY(cpu_xsc3_switch_mm)
356	clean_d_cache r1, r2
357	mcr	p15, 0, ip, c7, c5, 0		@ invalidate L1 I cache and BTB
358	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
359	mcr	p15, 0, ip, c7, c5, 4		@ prefetch flush
360	orr	r0, r0, #0x18			@ cache the page table in L2
361	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
362	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
363	cpwait_ret lr, ip
364
365/*
366 * cpu_xsc3_set_pte_ext(ptep, pte, ext)
367 *
368 * Set a PTE and flush it out
369 */
370cpu_xsc3_mt_table:
371	.long	0x00						@ L_PTE_MT_UNCACHED
372	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_BUFFERABLE
373	.long	PTE_EXT_TEX(5) | PTE_CACHEABLE			@ L_PTE_MT_WRITETHROUGH
374	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_WRITEBACK
375	.long	PTE_EXT_TEX(1) | PTE_BUFFERABLE			@ L_PTE_MT_DEV_SHARED
376	.long	0x00						@ unused
377	.long	0x00						@ L_PTE_MT_MINICACHE (not present)
378	.long	PTE_EXT_TEX(5) | PTE_CACHEABLE | PTE_BUFFERABLE	@ L_PTE_MT_WRITEALLOC (not present?)
379	.long	0x00						@ unused
380	.long	PTE_EXT_TEX(1)					@ L_PTE_MT_DEV_WC
381	.long	0x00						@ unused
382	.long	PTE_CACHEABLE | PTE_BUFFERABLE			@ L_PTE_MT_DEV_CACHED
383	.long	PTE_EXT_TEX(2)					@ L_PTE_MT_DEV_NONSHARED
384	.long	0x00						@ unused
385	.long	0x00						@ unused
386	.long	0x00						@ unused
387
388	.align	5
389ENTRY(cpu_xsc3_set_pte_ext)
390	xscale_set_pte_ext_prologue
391
392	tst	r1, #L_PTE_SHARED		@ shared?
393	and	r1, r1, #L_PTE_MT_MASK
394	adr	ip, cpu_xsc3_mt_table
395	ldr	ip, [ip, r1]
396	orrne	r2, r2, #PTE_EXT_COHERENT	@ interlock: mask in coherent bit
397	bic	r2, r2, #0x0c			@ clear old C,B bits
398	orr	r2, r2, ip
399
400	xscale_set_pte_ext_epilogue
401	mov	pc, lr
402
403	.ltorg
404
405	.align
406
407	__CPUINIT
408
409	.type	__xsc3_setup, #function
410__xsc3_setup:
411	mov	r0, #PSR_F_BIT|PSR_I_BIT|SVC_MODE
412	msr	cpsr_c, r0
413	mcr	p15, 0, ip, c7, c7, 0		@ invalidate L1 caches and BTB
414	mcr	p15, 0, ip, c7, c10, 4		@ data write barrier
415	mcr	p15, 0, ip, c7, c5, 4		@ prefetch flush
416	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I and D TLBs
417	orr	r4, r4, #0x18			@ cache the page table in L2
418	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer
419
420	mov	r0, #1 << 6			@ cp6 access for early sched_clock
421	mcr	p15, 0, r0, c15, c1, 0		@ write CP access register
422
423	mrc	p15, 0, r0, c1, c0, 1		@ get auxiliary control reg
424	and	r0, r0, #2			@ preserve bit P bit setting
425	orr	r0, r0, #(1 << 10)		@ enable L2 for LLR cache
426	mcr	p15, 0, r0, c1, c0, 1		@ set auxiliary control reg
427
428	adr	r5, xsc3_crval
429	ldmia	r5, {r5, r6}
430
431#ifdef CONFIG_CACHE_XSC3L2
432	mrc	p15, 1, r0, c0, c0, 1		@ get L2 present information
433	ands	r0, r0, #0xf8
434	orrne	r6, r6, #(1 << 26)		@ enable L2 if present
435#endif
436
437	mrc	p15, 0, r0, c1, c0, 0		@ get control register
438	bic	r0, r0, r5			@ ..V. ..R. .... ..A.
439	orr	r0, r0, r6			@ ..VI Z..S .... .C.M (mmu)
440						@ ...I Z..S .... .... (uc)
441	mov	pc, lr
442
443	.size	__xsc3_setup, . - __xsc3_setup
444
445	.type	xsc3_crval, #object
446xsc3_crval:
447	crval	clear=0x04002202, mmuset=0x00003905, ucset=0x00001900
448
449	__INITDATA
450
451/*
452 * Purpose : Function pointers used to access above functions - all calls
453 *	     come through these
454 */
455
456	.type	xsc3_processor_functions, #object
457ENTRY(xsc3_processor_functions)
458	.word	v5t_early_abort
459	.word	legacy_pabort
460	.word	cpu_xsc3_proc_init
461	.word	cpu_xsc3_proc_fin
462	.word	cpu_xsc3_reset
463	.word	cpu_xsc3_do_idle
464	.word	cpu_xsc3_dcache_clean_area
465	.word	cpu_xsc3_switch_mm
466	.word	cpu_xsc3_set_pte_ext
467	.size	xsc3_processor_functions, . - xsc3_processor_functions
468
469	.section ".rodata"
470
471	.type	cpu_arch_name, #object
472cpu_arch_name:
473	.asciz	"armv5te"
474	.size	cpu_arch_name, . - cpu_arch_name
475
476	.type	cpu_elf_name, #object
477cpu_elf_name:
478	.asciz	"v5"
479	.size	cpu_elf_name, . - cpu_elf_name
480
481	.type	cpu_xsc3_name, #object
482cpu_xsc3_name:
483	.asciz	"XScale-V3 based processor"
484	.size	cpu_xsc3_name, . - cpu_xsc3_name
485
486	.align
487
488	.section ".proc.info.init", #alloc, #execinstr
489
490	.type	__xsc3_proc_info,#object
491__xsc3_proc_info:
492	.long	0x69056000
493	.long	0xffffe000
494	.long	PMD_TYPE_SECT | \
495		PMD_SECT_BUFFERABLE | \
496		PMD_SECT_CACHEABLE | \
497		PMD_SECT_AP_WRITE | \
498		PMD_SECT_AP_READ
499	.long	PMD_TYPE_SECT | \
500		PMD_SECT_AP_WRITE | \
501		PMD_SECT_AP_READ
502	b	__xsc3_setup
503	.long	cpu_arch_name
504	.long	cpu_elf_name
505	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
506	.long	cpu_xsc3_name
507	.long	xsc3_processor_functions
508	.long	v4wbi_tlb_fns
509	.long	xsc3_mc_user_fns
510	.long	xsc3_cache_fns
511	.size	__xsc3_proc_info, . - __xsc3_proc_info
512
513/* Note: PXA935 changed its implementor ID from Intel to Marvell */
514
515	.type	__xsc3_pxa935_proc_info,#object
516__xsc3_pxa935_proc_info:
517	.long	0x56056000
518	.long	0xffffe000
519	.long	PMD_TYPE_SECT | \
520		PMD_SECT_BUFFERABLE | \
521		PMD_SECT_CACHEABLE | \
522		PMD_SECT_AP_WRITE | \
523		PMD_SECT_AP_READ
524	.long	PMD_TYPE_SECT | \
525		PMD_SECT_AP_WRITE | \
526		PMD_SECT_AP_READ
527	b	__xsc3_setup
528	.long	cpu_arch_name
529	.long	cpu_elf_name
530	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
531	.long	cpu_xsc3_name
532	.long	xsc3_processor_functions
533	.long	v4wbi_tlb_fns
534	.long	xsc3_mc_user_fns
535	.long	xsc3_cache_fns
536	.size	__xsc3_pxa935_proc_info, . - __xsc3_pxa935_proc_info
537