xref: /linux/arch/arm/mm/proc-arm1020.S (revision 20dfee95936413708701eb151f419597fdd9d948)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 *  linux/arch/arm/mm/proc-arm1020.S: MMU functions for ARM1020
4 *
5 *  Copyright (C) 2000 ARM Limited
6 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
7 *  hacked for non-paged-MM by Hyok S. Choi, 2003.
8 *
9 * These are the low level assembler for performing cache and TLB
10 * functions on the arm1020.
11 */
12#include <linux/linkage.h>
13#include <linux/init.h>
14#include <linux/cfi_types.h>
15#include <linux/pgtable.h>
16#include <asm/assembler.h>
17#include <asm/asm-offsets.h>
18#include <asm/hwcap.h>
19#include <asm/pgtable-hwdef.h>
20#include <asm/ptrace.h>
21
22#include "proc-macros.S"
23
24/*
25 * This is the maximum size of an area which will be invalidated
26 * using the single invalidate entry instructions.  Anything larger
27 * than this, and we go for the whole cache.
28 *
29 * This value should be chosen such that we choose the cheapest
30 * alternative.
31 */
32#define MAX_AREA_SIZE	32768
33
34/*
35 * The size of one data cache line.
36 */
37#define CACHE_DLINESIZE	32
38
39/*
40 * The number of data cache segments.
41 */
42#define CACHE_DSEGMENTS	16
43
44/*
45 * The number of lines in a cache segment.
46 */
47#define CACHE_DENTRIES	64
48
49/*
50 * This is the size at which it becomes more efficient to
51 * clean the whole cache, rather than using the individual
52 * cache line maintenance instructions.
53 */
54#define CACHE_DLIMIT	32768
55
56	.text
57/*
58 * cpu_arm1020_proc_init()
59 */
60SYM_TYPED_FUNC_START(cpu_arm1020_proc_init)
61	ret	lr
62SYM_FUNC_END(cpu_arm1020_proc_init)
63
64/*
65 * cpu_arm1020_proc_fin()
66 */
67SYM_TYPED_FUNC_START(cpu_arm1020_proc_fin)
68	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
69	bic	r0, r0, #0x1000 		@ ...i............
70	bic	r0, r0, #0x000e 		@ ............wca.
71	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
72	ret	lr
73SYM_FUNC_END(cpu_arm1020_proc_fin)
74
75/*
76 * cpu_arm1020_reset(loc)
77 *
78 * Perform a soft reset of the system.	Put the CPU into the
79 * same state as it would be if it had been reset, and branch
80 * to what would be the reset vector.
81 *
82 * loc: location to jump to for soft reset
83 */
84	.align	5
85	.pushsection	.idmap.text, "ax"
86SYM_TYPED_FUNC_START(cpu_arm1020_reset)
87	mov	ip, #0
88	mcr	p15, 0, ip, c7, c7, 0		@ invalidate I,D caches
89	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
90#ifdef CONFIG_MMU
91	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I & D TLBs
92#endif
93	mrc	p15, 0, ip, c1, c0, 0		@ ctrl register
94	bic	ip, ip, #0x000f 		@ ............wcam
95	bic	ip, ip, #0x1100 		@ ...i...s........
96	mcr	p15, 0, ip, c1, c0, 0		@ ctrl register
97	ret	r0
98SYM_FUNC_END(cpu_arm1020_reset)
99	.popsection
100
101/*
102 * cpu_arm1020_do_idle()
103 */
104	.align	5
105SYM_TYPED_FUNC_START(cpu_arm1020_do_idle)
106	mcr	p15, 0, r0, c7, c0, 4		@ Wait for interrupt
107	ret	lr
108SYM_FUNC_END(cpu_arm1020_do_idle)
109
110/* ================================= CACHE ================================ */
111
112	.align	5
113
114/*
115 *	flush_icache_all()
116 *
117 *	Unconditionally clean and invalidate the entire icache.
118 */
119SYM_TYPED_FUNC_START(arm1020_flush_icache_all)
120#ifndef CONFIG_CPU_ICACHE_DISABLE
121	mov	r0, #0
122	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
123#endif
124	ret	lr
125SYM_FUNC_END(arm1020_flush_icache_all)
126
127/*
128 *	flush_user_cache_all()
129 *
130 *	Invalidate all cache entries in a particular address
131 *	space.
132 */
133SYM_FUNC_ALIAS(arm1020_flush_user_cache_all, arm1020_flush_kern_cache_all)
134
135/*
136 *	flush_kern_cache_all()
137 *
138 *	Clean and invalidate the entire cache.
139 */
140SYM_TYPED_FUNC_START(arm1020_flush_kern_cache_all)
141	mov	r2, #VM_EXEC
142	mov	ip, #0
143__flush_whole_cache:
144#ifndef CONFIG_CPU_DCACHE_DISABLE
145	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
146	mov	r1, #(CACHE_DSEGMENTS - 1) << 5	@ 16 segments
1471:	orr	r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
1482:	mcr	p15, 0, r3, c7, c14, 2		@ clean+invalidate D index
149	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
150	subs	r3, r3, #1 << 26
151	bcs	2b				@ entries 63 to 0
152	subs	r1, r1, #1 << 5
153	bcs	1b				@ segments 15 to 0
154#endif
155	tst	r2, #VM_EXEC
156#ifndef CONFIG_CPU_ICACHE_DISABLE
157	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
158#endif
159	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
160	ret	lr
161SYM_FUNC_END(arm1020_flush_kern_cache_all)
162
163/*
164 *	flush_user_cache_range(start, end, flags)
165 *
166 *	Invalidate a range of cache entries in the specified
167 *	address space.
168 *
169 *	- start	- start address (inclusive)
170 *	- end	- end address (exclusive)
171 *	- flags	- vm_flags for this space
172 */
173SYM_TYPED_FUNC_START(arm1020_flush_user_cache_range)
174	mov	ip, #0
175	sub	r3, r1, r0			@ calculate total size
176	cmp	r3, #CACHE_DLIMIT
177	bhs	__flush_whole_cache
178
179#ifndef CONFIG_CPU_DCACHE_DISABLE
180	mcr	p15, 0, ip, c7, c10, 4
1811:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
182	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
183	add	r0, r0, #CACHE_DLINESIZE
184	cmp	r0, r1
185	blo	1b
186#endif
187	tst	r2, #VM_EXEC
188#ifndef CONFIG_CPU_ICACHE_DISABLE
189	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
190#endif
191	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
192	ret	lr
193SYM_FUNC_END(arm1020_flush_user_cache_range)
194
195/*
196 *	coherent_kern_range(start, end)
197 *
198 *	Ensure coherency between the Icache and the Dcache in the
199 *	region described by start.  If you have non-snooping
200 *	Harvard caches, you need to implement this function.
201 *
202 *	- start	- virtual start address
203 *	- end	- virtual end address
204 */
205SYM_TYPED_FUNC_START(arm1020_coherent_kern_range)
206#ifdef CONFIG_CFI_CLANG /* Fallthrough if !CFI */
207	b	arm1020_coherent_user_range
208#endif
209SYM_FUNC_END(arm1020_coherent_kern_range)
210
211/*
212 *	coherent_user_range(start, end)
213 *
214 *	Ensure coherency between the Icache and the Dcache in the
215 *	region described by start.  If you have non-snooping
216 *	Harvard caches, you need to implement this function.
217 *
218 *	- start	- virtual start address
219 *	- end	- virtual end address
220 */
221SYM_TYPED_FUNC_START(arm1020_coherent_user_range)
222	mov	ip, #0
223	bic	r0, r0, #CACHE_DLINESIZE - 1
224	mcr	p15, 0, ip, c7, c10, 4
2251:
226#ifndef CONFIG_CPU_DCACHE_DISABLE
227	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
228	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
229#endif
230#ifndef CONFIG_CPU_ICACHE_DISABLE
231	mcr	p15, 0, r0, c7, c5, 1		@ invalidate I entry
232#endif
233	add	r0, r0, #CACHE_DLINESIZE
234	cmp	r0, r1
235	blo	1b
236	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
237	mov	r0, #0
238	ret	lr
239SYM_FUNC_END(arm1020_coherent_user_range)
240
241/*
242 *	flush_kern_dcache_area(void *addr, size_t size)
243 *
244 *	Ensure no D cache aliasing occurs, either with itself or
245 *	the I cache
246 *
247 *	- addr	- kernel address
248 *	- size	- region size
249 */
250SYM_TYPED_FUNC_START(arm1020_flush_kern_dcache_area)
251	mov	ip, #0
252#ifndef CONFIG_CPU_DCACHE_DISABLE
253	add	r1, r0, r1
2541:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
255	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
256	add	r0, r0, #CACHE_DLINESIZE
257	cmp	r0, r1
258	blo	1b
259#endif
260	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
261	ret	lr
262SYM_FUNC_END(arm1020_flush_kern_dcache_area)
263
264/*
265 *	dma_inv_range(start, end)
266 *
267 *	Invalidate (discard) the specified virtual address range.
268 *	May not write back any entries.  If 'start' or 'end'
269 *	are not cache line aligned, those lines must be written
270 *	back.
271 *
272 *	- start	- virtual start address
273 *	- end	- virtual end address
274 *
275 * (same as v4wb)
276 */
277arm1020_dma_inv_range:
278	mov	ip, #0
279#ifndef CONFIG_CPU_DCACHE_DISABLE
280	tst	r0, #CACHE_DLINESIZE - 1
281	bic	r0, r0, #CACHE_DLINESIZE - 1
282	mcrne	p15, 0, ip, c7, c10, 4
283	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
284	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
285	tst	r1, #CACHE_DLINESIZE - 1
286	mcrne	p15, 0, ip, c7, c10, 4
287	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
288	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
2891:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
290	add	r0, r0, #CACHE_DLINESIZE
291	cmp	r0, r1
292	blo	1b
293#endif
294	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
295	ret	lr
296
297/*
298 *	dma_clean_range(start, end)
299 *
300 *	Clean the specified virtual address range.
301 *
302 *	- start	- virtual start address
303 *	- end	- virtual end address
304 *
305 * (same as v4wb)
306 */
307arm1020_dma_clean_range:
308	mov	ip, #0
309#ifndef CONFIG_CPU_DCACHE_DISABLE
310	bic	r0, r0, #CACHE_DLINESIZE - 1
3111:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
312	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
313	add	r0, r0, #CACHE_DLINESIZE
314	cmp	r0, r1
315	blo	1b
316#endif
317	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
318	ret	lr
319
320/*
321 *	dma_flush_range(start, end)
322 *
323 *	Clean and invalidate the specified virtual address range.
324 *
325 *	- start	- virtual start address
326 *	- end	- virtual end address
327 */
328SYM_TYPED_FUNC_START(arm1020_dma_flush_range)
329	mov	ip, #0
330#ifndef CONFIG_CPU_DCACHE_DISABLE
331	bic	r0, r0, #CACHE_DLINESIZE - 1
332	mcr	p15, 0, ip, c7, c10, 4
3331:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
334	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
335	add	r0, r0, #CACHE_DLINESIZE
336	cmp	r0, r1
337	blo	1b
338#endif
339	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
340	ret	lr
341SYM_FUNC_END(arm1020_dma_flush_range)
342
343/*
344 *	dma_map_area(start, size, dir)
345 *	- start	- kernel virtual start address
346 *	- size	- size of region
347 *	- dir	- DMA direction
348 */
349SYM_TYPED_FUNC_START(arm1020_dma_map_area)
350	add	r1, r1, r0
351	cmp	r2, #DMA_TO_DEVICE
352	beq	arm1020_dma_clean_range
353	bcs	arm1020_dma_inv_range
354	b	arm1020_dma_flush_range
355SYM_FUNC_END(arm1020_dma_map_area)
356
357/*
358 *	dma_unmap_area(start, size, dir)
359 *	- start	- kernel virtual start address
360 *	- size	- size of region
361 *	- dir	- DMA direction
362 */
363SYM_TYPED_FUNC_START(arm1020_dma_unmap_area)
364	ret	lr
365SYM_FUNC_END(arm1020_dma_unmap_area)
366
367	.align	5
368SYM_TYPED_FUNC_START(cpu_arm1020_dcache_clean_area)
369#ifndef CONFIG_CPU_DCACHE_DISABLE
370	mov	ip, #0
3711:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
372	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
373	add	r0, r0, #CACHE_DLINESIZE
374	subs	r1, r1, #CACHE_DLINESIZE
375	bhi	1b
376#endif
377	ret	lr
378SYM_FUNC_END(cpu_arm1020_dcache_clean_area)
379
380/* =============================== PageTable ============================== */
381
382/*
383 * cpu_arm1020_switch_mm(pgd)
384 *
385 * Set the translation base pointer to be as described by pgd.
386 *
387 * pgd: new page tables
388 */
389	.align	5
390SYM_TYPED_FUNC_START(cpu_arm1020_switch_mm)
391#ifdef CONFIG_MMU
392#ifndef CONFIG_CPU_DCACHE_DISABLE
393	mcr	p15, 0, r3, c7, c10, 4
394	mov	r1, #0xF			@ 16 segments
3951:	mov	r3, #0x3F			@ 64 entries
3962:	mov	ip, r3, LSL #26 		@ shift up entry
397	orr	ip, ip, r1, LSL #5		@ shift in/up index
398	mcr	p15, 0, ip, c7, c14, 2		@ Clean & Inval DCache entry
399	mov	ip, #0
400	mcr	p15, 0, ip, c7, c10, 4
401	subs	r3, r3, #1
402	cmp	r3, #0
403	bge	2b				@ entries 3F to 0
404	subs	r1, r1, #1
405	cmp	r1, #0
406	bge	1b				@ segments 15 to 0
407
408#endif
409	mov	r1, #0
410#ifndef CONFIG_CPU_ICACHE_DISABLE
411	mcr	p15, 0, r1, c7, c5, 0		@ invalidate I cache
412#endif
413	mcr	p15, 0, r1, c7, c10, 4		@ drain WB
414	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
415	mcr	p15, 0, r1, c8, c7, 0		@ invalidate I & D TLBs
416#endif /* CONFIG_MMU */
417	ret	lr
418SYM_FUNC_END(cpu_arm1020_switch_mm)
419
420/*
421 * cpu_arm1020_set_pte(ptep, pte)
422 *
423 * Set a PTE and flush it out
424 */
425	.align	5
426SYM_TYPED_FUNC_START(cpu_arm1020_set_pte_ext)
427#ifdef CONFIG_MMU
428	armv3_set_pte_ext
429	mov	r0, r0
430#ifndef CONFIG_CPU_DCACHE_DISABLE
431	mcr	p15, 0, r0, c7, c10, 4
432	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
433#endif
434	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
435#endif /* CONFIG_MMU */
436	ret	lr
437SYM_FUNC_END(cpu_arm1020_set_pte_ext)
438
439	.type	__arm1020_setup, #function
440__arm1020_setup:
441	mov	r0, #0
442	mcr	p15, 0, r0, c7, c7		@ invalidate I,D caches on v4
443	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer on v4
444#ifdef CONFIG_MMU
445	mcr	p15, 0, r0, c8, c7		@ invalidate I,D TLBs on v4
446#endif
447
448	adr	r5, arm1020_crval
449	ldmia	r5, {r5, r6}
450	mrc	p15, 0, r0, c1, c0		@ get control register v4
451	bic	r0, r0, r5
452	orr	r0, r0, r6
453#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
454	orr	r0, r0, #0x4000 		@ .R.. .... .... ....
455#endif
456	ret	lr
457	.size	__arm1020_setup, . - __arm1020_setup
458
459	/*
460	 *  R
461	 * .RVI ZFRS BLDP WCAM
462	 * .011 1001 ..11 0101
463	 */
464	.type	arm1020_crval, #object
465arm1020_crval:
466	crval	clear=0x0000593f, mmuset=0x00003935, ucset=0x00001930
467
468	__INITDATA
469	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
470	define_processor_functions arm1020, dabort=v4t_early_abort, pabort=legacy_pabort
471
472
473	.section ".rodata"
474
475	string	cpu_arch_name, "armv5t"
476	string	cpu_elf_name, "v5"
477
478	.type	cpu_arm1020_name, #object
479cpu_arm1020_name:
480	.ascii	"ARM1020"
481#ifndef CONFIG_CPU_ICACHE_DISABLE
482	.ascii	"i"
483#endif
484#ifndef CONFIG_CPU_DCACHE_DISABLE
485	.ascii	"d"
486#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
487	.ascii	"(wt)"
488#else
489	.ascii	"(wb)"
490#endif
491#endif
492#ifndef CONFIG_CPU_BPREDICT_DISABLE
493	.ascii	"B"
494#endif
495#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
496	.ascii	"RR"
497#endif
498	.ascii	"\0"
499	.size	cpu_arm1020_name, . - cpu_arm1020_name
500
501	.align
502
503	.section ".proc.info.init", "a"
504
505	.type	__arm1020_proc_info,#object
506__arm1020_proc_info:
507	.long	0x4104a200			@ ARM 1020T (Architecture v5T)
508	.long	0xff0ffff0
509	.long   PMD_TYPE_SECT | \
510		PMD_SECT_AP_WRITE | \
511		PMD_SECT_AP_READ
512	.long   PMD_TYPE_SECT | \
513		PMD_SECT_AP_WRITE | \
514		PMD_SECT_AP_READ
515	initfn	__arm1020_setup, __arm1020_proc_info
516	.long	cpu_arch_name
517	.long	cpu_elf_name
518	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
519	.long	cpu_arm1020_name
520	.long	arm1020_processor_functions
521	.long	v4wbi_tlb_fns
522	.long	v4wb_user_fns
523	.long	arm1020_cache_fns
524	.size	__arm1020_proc_info, . - __arm1020_proc_info
525