xref: /openbmc/linux/arch/arm/mm/proc-arm1020.S (revision 8c0b9ee8)
1/*
2 *  linux/arch/arm/mm/proc-arm1020.S: MMU functions for ARM1020
3 *
4 *  Copyright (C) 2000 ARM Limited
5 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
6 *  hacked for non-paged-MM by Hyok S. Choi, 2003.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21 *
22 *
23 * These are the low level assembler for performing cache and TLB
24 * functions on the arm1020.
25 *
26 *  CONFIG_CPU_ARM1020_CPU_IDLE -> nohlt
27 */
28#include <linux/linkage.h>
29#include <linux/init.h>
30#include <asm/assembler.h>
31#include <asm/asm-offsets.h>
32#include <asm/hwcap.h>
33#include <asm/pgtable-hwdef.h>
34#include <asm/pgtable.h>
35#include <asm/ptrace.h>
36
37#include "proc-macros.S"
38
39/*
40 * This is the maximum size of an area which will be invalidated
41 * using the single invalidate entry instructions.  Anything larger
42 * than this, and we go for the whole cache.
43 *
44 * This value should be chosen such that we choose the cheapest
45 * alternative.
46 */
47#define MAX_AREA_SIZE	32768
48
49/*
50 * The size of one data cache line.
51 */
52#define CACHE_DLINESIZE	32
53
54/*
55 * The number of data cache segments.
56 */
57#define CACHE_DSEGMENTS	16
58
59/*
60 * The number of lines in a cache segment.
61 */
62#define CACHE_DENTRIES	64
63
64/*
65 * This is the size at which it becomes more efficient to
66 * clean the whole cache, rather than using the individual
67 * cache line maintenance instructions.
68 */
69#define CACHE_DLIMIT	32768
70
71	.text
72/*
73 * cpu_arm1020_proc_init()
74 */
75ENTRY(cpu_arm1020_proc_init)
76	ret	lr
77
78/*
79 * cpu_arm1020_proc_fin()
80 */
81ENTRY(cpu_arm1020_proc_fin)
82	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
83	bic	r0, r0, #0x1000 		@ ...i............
84	bic	r0, r0, #0x000e 		@ ............wca.
85	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
86	ret	lr
87
88/*
89 * cpu_arm1020_reset(loc)
90 *
91 * Perform a soft reset of the system.	Put the CPU into the
92 * same state as it would be if it had been reset, and branch
93 * to what would be the reset vector.
94 *
95 * loc: location to jump to for soft reset
96 */
97	.align	5
98	.pushsection	.idmap.text, "ax"
99ENTRY(cpu_arm1020_reset)
100	mov	ip, #0
101	mcr	p15, 0, ip, c7, c7, 0		@ invalidate I,D caches
102	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
103#ifdef CONFIG_MMU
104	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I & D TLBs
105#endif
106	mrc	p15, 0, ip, c1, c0, 0		@ ctrl register
107	bic	ip, ip, #0x000f 		@ ............wcam
108	bic	ip, ip, #0x1100 		@ ...i...s........
109	mcr	p15, 0, ip, c1, c0, 0		@ ctrl register
110	ret	r0
111ENDPROC(cpu_arm1020_reset)
112	.popsection
113
114/*
115 * cpu_arm1020_do_idle()
116 */
117	.align	5
118ENTRY(cpu_arm1020_do_idle)
119	mcr	p15, 0, r0, c7, c0, 4		@ Wait for interrupt
120	ret	lr
121
122/* ================================= CACHE ================================ */
123
124	.align	5
125
126/*
127 *	flush_icache_all()
128 *
129 *	Unconditionally clean and invalidate the entire icache.
130 */
131ENTRY(arm1020_flush_icache_all)
132#ifndef CONFIG_CPU_ICACHE_DISABLE
133	mov	r0, #0
134	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
135#endif
136	ret	lr
137ENDPROC(arm1020_flush_icache_all)
138
139/*
140 *	flush_user_cache_all()
141 *
142 *	Invalidate all cache entries in a particular address
143 *	space.
144 */
145ENTRY(arm1020_flush_user_cache_all)
146	/* FALLTHROUGH */
147/*
148 *	flush_kern_cache_all()
149 *
150 *	Clean and invalidate the entire cache.
151 */
152ENTRY(arm1020_flush_kern_cache_all)
153	mov	r2, #VM_EXEC
154	mov	ip, #0
155__flush_whole_cache:
156#ifndef CONFIG_CPU_DCACHE_DISABLE
157	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
158	mov	r1, #(CACHE_DSEGMENTS - 1) << 5	@ 16 segments
1591:	orr	r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
1602:	mcr	p15, 0, r3, c7, c14, 2		@ clean+invalidate D index
161	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
162	subs	r3, r3, #1 << 26
163	bcs	2b				@ entries 63 to 0
164	subs	r1, r1, #1 << 5
165	bcs	1b				@ segments 15 to 0
166#endif
167	tst	r2, #VM_EXEC
168#ifndef CONFIG_CPU_ICACHE_DISABLE
169	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
170#endif
171	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
172	ret	lr
173
174/*
175 *	flush_user_cache_range(start, end, flags)
176 *
177 *	Invalidate a range of cache entries in the specified
178 *	address space.
179 *
180 *	- start	- start address (inclusive)
181 *	- end	- end address (exclusive)
182 *	- flags	- vm_flags for this space
183 */
184ENTRY(arm1020_flush_user_cache_range)
185	mov	ip, #0
186	sub	r3, r1, r0			@ calculate total size
187	cmp	r3, #CACHE_DLIMIT
188	bhs	__flush_whole_cache
189
190#ifndef CONFIG_CPU_DCACHE_DISABLE
191	mcr	p15, 0, ip, c7, c10, 4
1921:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
193	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
194	add	r0, r0, #CACHE_DLINESIZE
195	cmp	r0, r1
196	blo	1b
197#endif
198	tst	r2, #VM_EXEC
199#ifndef CONFIG_CPU_ICACHE_DISABLE
200	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
201#endif
202	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
203	ret	lr
204
205/*
206 *	coherent_kern_range(start, end)
207 *
208 *	Ensure coherency between the Icache and the Dcache in the
209 *	region described by start.  If you have non-snooping
210 *	Harvard caches, you need to implement this function.
211 *
212 *	- start	- virtual start address
213 *	- end	- virtual end address
214 */
215ENTRY(arm1020_coherent_kern_range)
216	/* FALLTRHOUGH */
217
218/*
219 *	coherent_user_range(start, end)
220 *
221 *	Ensure coherency between the Icache and the Dcache in the
222 *	region described by start.  If you have non-snooping
223 *	Harvard caches, you need to implement this function.
224 *
225 *	- start	- virtual start address
226 *	- end	- virtual end address
227 */
228ENTRY(arm1020_coherent_user_range)
229	mov	ip, #0
230	bic	r0, r0, #CACHE_DLINESIZE - 1
231	mcr	p15, 0, ip, c7, c10, 4
2321:
233#ifndef CONFIG_CPU_DCACHE_DISABLE
234	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
235	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
236#endif
237#ifndef CONFIG_CPU_ICACHE_DISABLE
238	mcr	p15, 0, r0, c7, c5, 1		@ invalidate I entry
239#endif
240	add	r0, r0, #CACHE_DLINESIZE
241	cmp	r0, r1
242	blo	1b
243	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
244	mov	r0, #0
245	ret	lr
246
247/*
248 *	flush_kern_dcache_area(void *addr, size_t size)
249 *
250 *	Ensure no D cache aliasing occurs, either with itself or
251 *	the I cache
252 *
253 *	- addr	- kernel address
254 *	- size	- region size
255 */
256ENTRY(arm1020_flush_kern_dcache_area)
257	mov	ip, #0
258#ifndef CONFIG_CPU_DCACHE_DISABLE
259	add	r1, r0, r1
2601:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
261	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
262	add	r0, r0, #CACHE_DLINESIZE
263	cmp	r0, r1
264	blo	1b
265#endif
266	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
267	ret	lr
268
269/*
270 *	dma_inv_range(start, end)
271 *
272 *	Invalidate (discard) the specified virtual address range.
273 *	May not write back any entries.  If 'start' or 'end'
274 *	are not cache line aligned, those lines must be written
275 *	back.
276 *
277 *	- start	- virtual start address
278 *	- end	- virtual end address
279 *
280 * (same as v4wb)
281 */
282arm1020_dma_inv_range:
283	mov	ip, #0
284#ifndef CONFIG_CPU_DCACHE_DISABLE
285	tst	r0, #CACHE_DLINESIZE - 1
286	bic	r0, r0, #CACHE_DLINESIZE - 1
287	mcrne	p15, 0, ip, c7, c10, 4
288	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
289	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
290	tst	r1, #CACHE_DLINESIZE - 1
291	mcrne	p15, 0, ip, c7, c10, 4
292	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
293	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
2941:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
295	add	r0, r0, #CACHE_DLINESIZE
296	cmp	r0, r1
297	blo	1b
298#endif
299	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
300	ret	lr
301
302/*
303 *	dma_clean_range(start, end)
304 *
305 *	Clean the specified virtual address range.
306 *
307 *	- start	- virtual start address
308 *	- end	- virtual end address
309 *
310 * (same as v4wb)
311 */
312arm1020_dma_clean_range:
313	mov	ip, #0
314#ifndef CONFIG_CPU_DCACHE_DISABLE
315	bic	r0, r0, #CACHE_DLINESIZE - 1
3161:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
317	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
318	add	r0, r0, #CACHE_DLINESIZE
319	cmp	r0, r1
320	blo	1b
321#endif
322	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
323	ret	lr
324
325/*
326 *	dma_flush_range(start, end)
327 *
328 *	Clean and invalidate the specified virtual address range.
329 *
330 *	- start	- virtual start address
331 *	- end	- virtual end address
332 */
333ENTRY(arm1020_dma_flush_range)
334	mov	ip, #0
335#ifndef CONFIG_CPU_DCACHE_DISABLE
336	bic	r0, r0, #CACHE_DLINESIZE - 1
337	mcr	p15, 0, ip, c7, c10, 4
3381:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
339	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
340	add	r0, r0, #CACHE_DLINESIZE
341	cmp	r0, r1
342	blo	1b
343#endif
344	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
345	ret	lr
346
347/*
348 *	dma_map_area(start, size, dir)
349 *	- start	- kernel virtual start address
350 *	- size	- size of region
351 *	- dir	- DMA direction
352 */
353ENTRY(arm1020_dma_map_area)
354	add	r1, r1, r0
355	cmp	r2, #DMA_TO_DEVICE
356	beq	arm1020_dma_clean_range
357	bcs	arm1020_dma_inv_range
358	b	arm1020_dma_flush_range
359ENDPROC(arm1020_dma_map_area)
360
361/*
362 *	dma_unmap_area(start, size, dir)
363 *	- start	- kernel virtual start address
364 *	- size	- size of region
365 *	- dir	- DMA direction
366 */
367ENTRY(arm1020_dma_unmap_area)
368	ret	lr
369ENDPROC(arm1020_dma_unmap_area)
370
371	.globl	arm1020_flush_kern_cache_louis
372	.equ	arm1020_flush_kern_cache_louis, arm1020_flush_kern_cache_all
373
374	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
375	define_cache_functions arm1020
376
377	.align	5
378ENTRY(cpu_arm1020_dcache_clean_area)
379#ifndef CONFIG_CPU_DCACHE_DISABLE
380	mov	ip, #0
3811:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
382	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
383	add	r0, r0, #CACHE_DLINESIZE
384	subs	r1, r1, #CACHE_DLINESIZE
385	bhi	1b
386#endif
387	ret	lr
388
389/* =============================== PageTable ============================== */
390
391/*
392 * cpu_arm1020_switch_mm(pgd)
393 *
394 * Set the translation base pointer to be as described by pgd.
395 *
396 * pgd: new page tables
397 */
398	.align	5
399ENTRY(cpu_arm1020_switch_mm)
400#ifdef CONFIG_MMU
401#ifndef CONFIG_CPU_DCACHE_DISABLE
402	mcr	p15, 0, r3, c7, c10, 4
403	mov	r1, #0xF			@ 16 segments
4041:	mov	r3, #0x3F			@ 64 entries
4052:	mov	ip, r3, LSL #26 		@ shift up entry
406	orr	ip, ip, r1, LSL #5		@ shift in/up index
407	mcr	p15, 0, ip, c7, c14, 2		@ Clean & Inval DCache entry
408	mov	ip, #0
409	mcr	p15, 0, ip, c7, c10, 4
410	subs	r3, r3, #1
411	cmp	r3, #0
412	bge	2b				@ entries 3F to 0
413	subs	r1, r1, #1
414	cmp	r1, #0
415	bge	1b				@ segments 15 to 0
416
417#endif
418	mov	r1, #0
419#ifndef CONFIG_CPU_ICACHE_DISABLE
420	mcr	p15, 0, r1, c7, c5, 0		@ invalidate I cache
421#endif
422	mcr	p15, 0, r1, c7, c10, 4		@ drain WB
423	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
424	mcr	p15, 0, r1, c8, c7, 0		@ invalidate I & D TLBs
425#endif /* CONFIG_MMU */
426	ret	lr
427
428/*
429 * cpu_arm1020_set_pte(ptep, pte)
430 *
431 * Set a PTE and flush it out
432 */
433	.align	5
434ENTRY(cpu_arm1020_set_pte_ext)
435#ifdef CONFIG_MMU
436	armv3_set_pte_ext
437	mov	r0, r0
438#ifndef CONFIG_CPU_DCACHE_DISABLE
439	mcr	p15, 0, r0, c7, c10, 4
440	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
441#endif
442	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
443#endif /* CONFIG_MMU */
444	ret	lr
445
446	.type	__arm1020_setup, #function
447__arm1020_setup:
448	mov	r0, #0
449	mcr	p15, 0, r0, c7, c7		@ invalidate I,D caches on v4
450	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer on v4
451#ifdef CONFIG_MMU
452	mcr	p15, 0, r0, c8, c7		@ invalidate I,D TLBs on v4
453#endif
454
455	adr	r5, arm1020_crval
456	ldmia	r5, {r5, r6}
457	mrc	p15, 0, r0, c1, c0		@ get control register v4
458	bic	r0, r0, r5
459	orr	r0, r0, r6
460#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
461	orr	r0, r0, #0x4000 		@ .R.. .... .... ....
462#endif
463	ret	lr
464	.size	__arm1020_setup, . - __arm1020_setup
465
466	/*
467	 *  R
468	 * .RVI ZFRS BLDP WCAM
469	 * .011 1001 ..11 0101
470	 */
471	.type	arm1020_crval, #object
472arm1020_crval:
473	crval	clear=0x0000593f, mmuset=0x00003935, ucset=0x00001930
474
475	__INITDATA
476	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
477	define_processor_functions arm1020, dabort=v4t_early_abort, pabort=legacy_pabort
478
479
480	.section ".rodata"
481
482	string	cpu_arch_name, "armv5t"
483	string	cpu_elf_name, "v5"
484
485	.type	cpu_arm1020_name, #object
486cpu_arm1020_name:
487	.ascii	"ARM1020"
488#ifndef CONFIG_CPU_ICACHE_DISABLE
489	.ascii	"i"
490#endif
491#ifndef CONFIG_CPU_DCACHE_DISABLE
492	.ascii	"d"
493#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
494	.ascii	"(wt)"
495#else
496	.ascii	"(wb)"
497#endif
498#endif
499#ifndef CONFIG_CPU_BPREDICT_DISABLE
500	.ascii	"B"
501#endif
502#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
503	.ascii	"RR"
504#endif
505	.ascii	"\0"
506	.size	cpu_arm1020_name, . - cpu_arm1020_name
507
508	.align
509
510	.section ".proc.info.init", #alloc, #execinstr
511
512	.type	__arm1020_proc_info,#object
513__arm1020_proc_info:
514	.long	0x4104a200			@ ARM 1020T (Architecture v5T)
515	.long	0xff0ffff0
516	.long   PMD_TYPE_SECT | \
517		PMD_SECT_AP_WRITE | \
518		PMD_SECT_AP_READ
519	.long   PMD_TYPE_SECT | \
520		PMD_SECT_AP_WRITE | \
521		PMD_SECT_AP_READ
522	b	__arm1020_setup
523	.long	cpu_arch_name
524	.long	cpu_elf_name
525	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
526	.long	cpu_arm1020_name
527	.long	arm1020_processor_functions
528	.long	v4wbi_tlb_fns
529	.long	v4wb_user_fns
530	.long	arm1020_cache_fns
531	.size	__arm1020_proc_info, . - __arm1020_proc_info
532