xref: /openbmc/linux/arch/arm/mm/proc-arm1020.S (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20 *
21 *
22 * These are the low level assembler for performing cache and TLB
23 * functions on the arm1020.
24 *
25 *  CONFIG_CPU_ARM1020_CPU_IDLE -> nohlt
26 */
27#include <linux/linkage.h>
28#include <linux/config.h>
29#include <linux/init.h>
30#include <asm/assembler.h>
31#include <asm/constants.h>
32#include <asm/pgtable.h>
33#include <asm/procinfo.h>
34#include <asm/ptrace.h>
35#include <asm/hardware.h>
36
37/*
38 * This is the maximum size of an area which will be invalidated
39 * using the single invalidate entry instructions.  Anything larger
40 * than this, and we go for the whole cache.
41 *
42 * This value should be chosen such that we choose the cheapest
43 * alternative.
44 */
45#define MAX_AREA_SIZE	32768
46
47/*
48 * The size of one data cache line.
49 */
50#define CACHE_DLINESIZE	32
51
52/*
53 * The number of data cache segments.
54 */
55#define CACHE_DSEGMENTS	16
56
57/*
58 * The number of lines in a cache segment.
59 */
60#define CACHE_DENTRIES	64
61
62/*
63 * This is the size at which it becomes more efficient to
64 * clean the whole cache, rather than using the individual
65 * cache line maintainence instructions.
66 */
67#define CACHE_DLIMIT	32768
68
69	.text
70/*
71 * cpu_arm1020_proc_init()
72 */
73ENTRY(cpu_arm1020_proc_init)
74	mov	pc, lr
75
76/*
77 * cpu_arm1020_proc_fin()
78 */
79ENTRY(cpu_arm1020_proc_fin)
80	stmfd	sp!, {lr}
81	mov	ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
82	msr	cpsr_c, ip
83	bl	arm1020_flush_kern_cache_all
84	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
85	bic	r0, r0, #0x1000 		@ ...i............
86	bic	r0, r0, #0x000e 		@ ............wca.
87	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
88	ldmfd	sp!, {pc}
89
90/*
91 * cpu_arm1020_reset(loc)
92 *
93 * Perform a soft reset of the system.	Put the CPU into the
94 * same state as it would be if it had been reset, and branch
95 * to what would be the reset vector.
96 *
97 * loc: location to jump to for soft reset
98 */
99	.align	5
100ENTRY(cpu_arm1020_reset)
101	mov	ip, #0
102	mcr	p15, 0, ip, c7, c7, 0		@ invalidate I,D caches
103	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
104	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I & D TLBs
105	mrc	p15, 0, ip, c1, c0, 0		@ ctrl register
106	bic	ip, ip, #0x000f 		@ ............wcam
107	bic	ip, ip, #0x1100 		@ ...i...s........
108	mcr	p15, 0, ip, c1, c0, 0		@ ctrl register
109	mov	pc, r0
110
111/*
112 * cpu_arm1020_do_idle()
113 */
114	.align	5
115ENTRY(cpu_arm1020_do_idle)
116	mcr	p15, 0, r0, c7, c0, 4		@ Wait for interrupt
117	mov	pc, lr
118
119/* ================================= CACHE ================================ */
120
121	.align	5
122/*
123 *	flush_user_cache_all()
124 *
125 *	Invalidate all cache entries in a particular address
126 *	space.
127 */
128ENTRY(arm1020_flush_user_cache_all)
129	/* FALLTHROUGH */
130/*
131 *	flush_kern_cache_all()
132 *
133 *	Clean and invalidate the entire cache.
134 */
135ENTRY(arm1020_flush_kern_cache_all)
136	mov	r2, #VM_EXEC
137	mov	ip, #0
138__flush_whole_cache:
139#ifndef CONFIG_CPU_DCACHE_DISABLE
140	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
141	mov	r1, #(CACHE_DSEGMENTS - 1) << 5	@ 16 segments
1421:	orr	r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
1432:	mcr	p15, 0, r3, c7, c14, 2		@ clean+invalidate D index
144	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
145	subs	r3, r3, #1 << 26
146	bcs	2b				@ entries 63 to 0
147	subs	r1, r1, #1 << 5
148	bcs	1b				@ segments 15 to 0
149#endif
150	tst	r2, #VM_EXEC
151#ifndef CONFIG_CPU_ICACHE_DISABLE
152	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
153#endif
154	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
155	mov	pc, lr
156
157/*
158 *	flush_user_cache_range(start, end, flags)
159 *
160 *	Invalidate a range of cache entries in the specified
161 *	address space.
162 *
163 *	- start	- start address (inclusive)
164 *	- end	- end address (exclusive)
165 *	- flags	- vm_flags for this space
166 */
167ENTRY(arm1020_flush_user_cache_range)
168	mov	ip, #0
169	sub	r3, r1, r0			@ calculate total size
170	cmp	r3, #CACHE_DLIMIT
171	bhs	__flush_whole_cache
172
173#ifndef CONFIG_CPU_DCACHE_DISABLE
174	mcr	p15, 0, ip, c7, c10, 4
1751:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
176	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
177	add	r0, r0, #CACHE_DLINESIZE
178	cmp	r0, r1
179	blo	1b
180#endif
181	tst	r2, #VM_EXEC
182#ifndef CONFIG_CPU_ICACHE_DISABLE
183	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
184#endif
185	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
186	mov	pc, lr
187
188/*
189 *	coherent_kern_range(start, end)
190 *
191 *	Ensure coherency between the Icache and the Dcache in the
192 *	region described by start.  If you have non-snooping
193 *	Harvard caches, you need to implement this function.
194 *
195 *	- start	- virtual start address
196 *	- end	- virtual end address
197 */
198ENTRY(arm1020_coherent_kern_range)
199	/* FALLTRHOUGH */
200
201/*
202 *	coherent_user_range(start, end)
203 *
204 *	Ensure coherency between the Icache and the Dcache 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 */
211ENTRY(arm1020_coherent_user_range)
212	mov	ip, #0
213	bic	r0, r0, #CACHE_DLINESIZE - 1
214	mcr	p15, 0, ip, c7, c10, 4
2151:
216#ifndef CONFIG_CPU_DCACHE_DISABLE
217	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
218	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
219#endif
220#ifndef CONFIG_CPU_ICACHE_DISABLE
221	mcr	p15, 0, r0, c7, c5, 1		@ invalidate I entry
222#endif
223	add	r0, r0, #CACHE_DLINESIZE
224	cmp	r0, r1
225	blo	1b
226	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
227	mov	pc, lr
228
229/*
230 *	flush_kern_dcache_page(void *page)
231 *
232 *	Ensure no D cache aliasing occurs, either with itself or
233 *	the I cache
234 *
235 *	- page	- page aligned address
236 */
237ENTRY(arm1020_flush_kern_dcache_page)
238	mov	ip, #0
239#ifndef CONFIG_CPU_DCACHE_DISABLE
240	add	r1, r0, #PAGE_SZ
2411:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
242	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
243	add	r0, r0, #CACHE_DLINESIZE
244	cmp	r0, r1
245	blo	1b
246#endif
247	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
248	mov	pc, lr
249
250/*
251 *	dma_inv_range(start, end)
252 *
253 *	Invalidate (discard) the specified virtual address range.
254 *	May not write back any entries.  If 'start' or 'end'
255 *	are not cache line aligned, those lines must be written
256 *	back.
257 *
258 *	- start	- virtual start address
259 *	- end	- virtual end address
260 *
261 * (same as v4wb)
262 */
263ENTRY(arm1020_dma_inv_range)
264	mov	ip, #0
265#ifndef CONFIG_CPU_DCACHE_DISABLE
266	tst	r0, #CACHE_DLINESIZE - 1
267	bic	r0, r0, #CACHE_DLINESIZE - 1
268	mcrne	p15, 0, ip, c7, c10, 4
269	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
270	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
271	tst	r1, #CACHE_DLINESIZE - 1
272	mcrne	p15, 0, ip, c7, c10, 4
273	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
274	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
2751:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
276	add	r0, r0, #CACHE_DLINESIZE
277	cmp	r0, r1
278	blo	1b
279#endif
280	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
281	mov	pc, lr
282
283/*
284 *	dma_clean_range(start, end)
285 *
286 *	Clean the specified virtual address range.
287 *
288 *	- start	- virtual start address
289 *	- end	- virtual end address
290 *
291 * (same as v4wb)
292 */
293ENTRY(arm1020_dma_clean_range)
294	mov	ip, #0
295#ifndef CONFIG_CPU_DCACHE_DISABLE
296	bic	r0, r0, #CACHE_DLINESIZE - 1
2971:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
298	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
299	add	r0, r0, #CACHE_DLINESIZE
300	cmp	r0, r1
301	blo	1b
302#endif
303	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
304	mov	pc, lr
305
306/*
307 *	dma_flush_range(start, end)
308 *
309 *	Clean and invalidate the specified virtual address range.
310 *
311 *	- start	- virtual start address
312 *	- end	- virtual end address
313 */
314ENTRY(arm1020_dma_flush_range)
315	mov	ip, #0
316#ifndef CONFIG_CPU_DCACHE_DISABLE
317	bic	r0, r0, #CACHE_DLINESIZE - 1
318	mcr	p15, 0, ip, c7, c10, 4
3191:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
320	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
321	add	r0, r0, #CACHE_DLINESIZE
322	cmp	r0, r1
323	blo	1b
324#endif
325	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
326	mov	pc, lr
327
328ENTRY(arm1020_cache_fns)
329	.long	arm1020_flush_kern_cache_all
330	.long	arm1020_flush_user_cache_all
331	.long	arm1020_flush_user_cache_range
332	.long	arm1020_coherent_kern_range
333	.long	arm1020_coherent_user_range
334	.long	arm1020_flush_kern_dcache_page
335	.long	arm1020_dma_inv_range
336	.long	arm1020_dma_clean_range
337	.long	arm1020_dma_flush_range
338
339	.align	5
340ENTRY(cpu_arm1020_dcache_clean_area)
341#ifndef CONFIG_CPU_DCACHE_DISABLE
342	mov	ip, #0
3431:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
344	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
345	add	r0, r0, #CACHE_DLINESIZE
346	subs	r1, r1, #CACHE_DLINESIZE
347	bhi	1b
348#endif
349	mov	pc, lr
350
351/* =============================== PageTable ============================== */
352
353/*
354 * cpu_arm1020_switch_mm(pgd)
355 *
356 * Set the translation base pointer to be as described by pgd.
357 *
358 * pgd: new page tables
359 */
360	.align	5
361ENTRY(cpu_arm1020_switch_mm)
362#ifndef CONFIG_CPU_DCACHE_DISABLE
363	mcr	p15, 0, r3, c7, c10, 4
364	mov	r1, #0xF			@ 16 segments
3651:	mov	r3, #0x3F			@ 64 entries
3662:	mov	ip, r3, LSL #26 		@ shift up entry
367	orr	ip, ip, r1, LSL #5		@ shift in/up index
368	mcr	p15, 0, ip, c7, c14, 2		@ Clean & Inval DCache entry
369	mov	ip, #0
370	mcr	p15, 0, ip, c7, c10, 4
371	subs	r3, r3, #1
372	cmp	r3, #0
373	bge	2b				@ entries 3F to 0
374	subs	r1, r1, #1
375	cmp	r1, #0
376	bge	1b				@ segments 15 to 0
377
378#endif
379	mov	r1, #0
380#ifndef CONFIG_CPU_ICACHE_DISABLE
381	mcr	p15, 0, r1, c7, c5, 0		@ invalidate I cache
382#endif
383	mcr	p15, 0, r1, c7, c10, 4		@ drain WB
384	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
385	mcr	p15, 0, r1, c8, c7, 0		@ invalidate I & D TLBs
386	mov	pc, lr
387
388/*
389 * cpu_arm1020_set_pte(ptep, pte)
390 *
391 * Set a PTE and flush it out
392 */
393	.align	5
394ENTRY(cpu_arm1020_set_pte)
395	str	r1, [r0], #-2048		@ linux version
396
397	eor	r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
398
399	bic	r2, r1, #PTE_SMALL_AP_MASK
400	bic	r2, r2, #PTE_TYPE_MASK
401	orr	r2, r2, #PTE_TYPE_SMALL
402
403	tst	r1, #L_PTE_USER			@ User?
404	orrne	r2, r2, #PTE_SMALL_AP_URO_SRW
405
406	tst	r1, #L_PTE_WRITE | L_PTE_DIRTY	@ Write and Dirty?
407	orreq	r2, r2, #PTE_SMALL_AP_UNO_SRW
408
409	tst	r1, #L_PTE_PRESENT | L_PTE_YOUNG	@ Present and Young?
410	movne	r2, #0
411
412#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
413	eor	r3, r1, #0x0a			@ C & small page?
414	tst	r3, #0x0b
415	biceq	r2, r2, #4
416#endif
417	str	r2, [r0]			@ hardware version
418	mov	r0, r0
419#ifndef CONFIG_CPU_DCACHE_DISABLE
420	mcr	p15, 0, r0, c7, c10, 4
421	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
422#endif
423	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
424	mov	pc, lr
425
426	__INIT
427
428	.type	__arm1020_setup, #function
429__arm1020_setup:
430	mov	r0, #0
431	mcr	p15, 0, r0, c7, c7		@ invalidate I,D caches on v4
432	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer on v4
433	mcr	p15, 0, r0, c8, c7		@ invalidate I,D TLBs on v4
434	mrc	p15, 0, r0, c1, c0		@ get control register v4
435	ldr	r5, arm1020_cr1_clear
436	bic	r0, r0, r5
437	ldr	r5, arm1020_cr1_set
438	orr	r0, r0, r5
439#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
440	orr	r0, r0, #0x4000 		@ .R.. .... .... ....
441#endif
442	mov	pc, lr
443	.size	__arm1020_setup, . - __arm1020_setup
444
445	/*
446	 *  R
447	 * .RVI ZFRS BLDP WCAM
448	 * .0.1 1001 ..11 0101	/* FIXME: why no V bit? */
449	 */
450	.type	arm1020_cr1_clear, #object
451	.type	arm1020_cr1_set, #object
452arm1020_cr1_clear:
453	.word	0x593f
454arm1020_cr1_set:
455	.word	0x1935
456
457	__INITDATA
458
459/*
460 * Purpose : Function pointers used to access above functions - all calls
461 *	     come through these
462 */
463	.type	arm1020_processor_functions, #object
464arm1020_processor_functions:
465	.word	v4t_early_abort
466	.word	cpu_arm1020_proc_init
467	.word	cpu_arm1020_proc_fin
468	.word	cpu_arm1020_reset
469	.word	cpu_arm1020_do_idle
470	.word	cpu_arm1020_dcache_clean_area
471	.word	cpu_arm1020_switch_mm
472	.word	cpu_arm1020_set_pte
473	.size	arm1020_processor_functions, . - arm1020_processor_functions
474
475	.section ".rodata"
476
477	.type	cpu_arch_name, #object
478cpu_arch_name:
479	.asciz	"armv5t"
480	.size	cpu_arch_name, . - cpu_arch_name
481
482	.type	cpu_elf_name, #object
483cpu_elf_name:
484	.asciz	"v5"
485	.size	cpu_elf_name, . - cpu_elf_name
486
487	.type	cpu_arm1020_name, #object
488cpu_arm1020_name:
489	.ascii	"ARM1020"
490#ifndef CONFIG_CPU_ICACHE_DISABLE
491	.ascii	"i"
492#endif
493#ifndef CONFIG_CPU_DCACHE_DISABLE
494	.ascii	"d"
495#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
496	.ascii	"(wt)"
497#else
498	.ascii	"(wb)"
499#endif
500#endif
501#ifndef CONFIG_CPU_BPREDICT_DISABLE
502	.ascii	"B"
503#endif
504#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
505	.ascii	"RR"
506#endif
507	.ascii	"\0"
508	.size	cpu_arm1020_name, . - cpu_arm1020_name
509
510	.align
511
512	.section ".proc.info", #alloc, #execinstr
513
514	.type	__arm1020_proc_info,#object
515__arm1020_proc_info:
516	.long	0x4104a200			@ ARM 1020T (Architecture v5T)
517	.long	0xff0ffff0
518	.long   PMD_TYPE_SECT | \
519		PMD_SECT_AP_WRITE | \
520		PMD_SECT_AP_READ
521	b	__arm1020_setup
522	.long	cpu_arch_name
523	.long	cpu_elf_name
524	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
525	.long	cpu_arm1020_name
526	.long	arm1020_processor_functions
527	.long	v4wbi_tlb_fns
528	.long	v4wb_user_fns
529	.long	arm1020_cache_fns
530	.size	__arm1020_proc_info, . - __arm1020_proc_info
531