xref: /openbmc/linux/arch/arm/mm/proc-arm1020.S (revision e72e8bf1)
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 <asm/assembler.h>
15#include <asm/asm-offsets.h>
16#include <asm/hwcap.h>
17#include <asm/pgtable-hwdef.h>
18#include <asm/pgtable.h>
19#include <asm/ptrace.h>
20
21#include "proc-macros.S"
22
23/*
24 * This is the maximum size of an area which will be invalidated
25 * using the single invalidate entry instructions.  Anything larger
26 * than this, and we go for the whole cache.
27 *
28 * This value should be chosen such that we choose the cheapest
29 * alternative.
30 */
31#define MAX_AREA_SIZE	32768
32
33/*
34 * The size of one data cache line.
35 */
36#define CACHE_DLINESIZE	32
37
38/*
39 * The number of data cache segments.
40 */
41#define CACHE_DSEGMENTS	16
42
43/*
44 * The number of lines in a cache segment.
45 */
46#define CACHE_DENTRIES	64
47
48/*
49 * This is the size at which it becomes more efficient to
50 * clean the whole cache, rather than using the individual
51 * cache line maintenance instructions.
52 */
53#define CACHE_DLIMIT	32768
54
55	.text
56/*
57 * cpu_arm1020_proc_init()
58 */
59ENTRY(cpu_arm1020_proc_init)
60	ret	lr
61
62/*
63 * cpu_arm1020_proc_fin()
64 */
65ENTRY(cpu_arm1020_proc_fin)
66	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
67	bic	r0, r0, #0x1000 		@ ...i............
68	bic	r0, r0, #0x000e 		@ ............wca.
69	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
70	ret	lr
71
72/*
73 * cpu_arm1020_reset(loc)
74 *
75 * Perform a soft reset of the system.	Put the CPU into the
76 * same state as it would be if it had been reset, and branch
77 * to what would be the reset vector.
78 *
79 * loc: location to jump to for soft reset
80 */
81	.align	5
82	.pushsection	.idmap.text, "ax"
83ENTRY(cpu_arm1020_reset)
84	mov	ip, #0
85	mcr	p15, 0, ip, c7, c7, 0		@ invalidate I,D caches
86	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
87#ifdef CONFIG_MMU
88	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I & D TLBs
89#endif
90	mrc	p15, 0, ip, c1, c0, 0		@ ctrl register
91	bic	ip, ip, #0x000f 		@ ............wcam
92	bic	ip, ip, #0x1100 		@ ...i...s........
93	mcr	p15, 0, ip, c1, c0, 0		@ ctrl register
94	ret	r0
95ENDPROC(cpu_arm1020_reset)
96	.popsection
97
98/*
99 * cpu_arm1020_do_idle()
100 */
101	.align	5
102ENTRY(cpu_arm1020_do_idle)
103	mcr	p15, 0, r0, c7, c0, 4		@ Wait for interrupt
104	ret	lr
105
106/* ================================= CACHE ================================ */
107
108	.align	5
109
110/*
111 *	flush_icache_all()
112 *
113 *	Unconditionally clean and invalidate the entire icache.
114 */
115ENTRY(arm1020_flush_icache_all)
116#ifndef CONFIG_CPU_ICACHE_DISABLE
117	mov	r0, #0
118	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
119#endif
120	ret	lr
121ENDPROC(arm1020_flush_icache_all)
122
123/*
124 *	flush_user_cache_all()
125 *
126 *	Invalidate all cache entries in a particular address
127 *	space.
128 */
129ENTRY(arm1020_flush_user_cache_all)
130	/* FALLTHROUGH */
131/*
132 *	flush_kern_cache_all()
133 *
134 *	Clean and invalidate the entire cache.
135 */
136ENTRY(arm1020_flush_kern_cache_all)
137	mov	r2, #VM_EXEC
138	mov	ip, #0
139__flush_whole_cache:
140#ifndef CONFIG_CPU_DCACHE_DISABLE
141	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
142	mov	r1, #(CACHE_DSEGMENTS - 1) << 5	@ 16 segments
1431:	orr	r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
1442:	mcr	p15, 0, r3, c7, c14, 2		@ clean+invalidate D index
145	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
146	subs	r3, r3, #1 << 26
147	bcs	2b				@ entries 63 to 0
148	subs	r1, r1, #1 << 5
149	bcs	1b				@ segments 15 to 0
150#endif
151	tst	r2, #VM_EXEC
152#ifndef CONFIG_CPU_ICACHE_DISABLE
153	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
154#endif
155	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
156	ret	lr
157
158/*
159 *	flush_user_cache_range(start, end, flags)
160 *
161 *	Invalidate a range of cache entries in the specified
162 *	address space.
163 *
164 *	- start	- start address (inclusive)
165 *	- end	- end address (exclusive)
166 *	- flags	- vm_flags for this space
167 */
168ENTRY(arm1020_flush_user_cache_range)
169	mov	ip, #0
170	sub	r3, r1, r0			@ calculate total size
171	cmp	r3, #CACHE_DLIMIT
172	bhs	__flush_whole_cache
173
174#ifndef CONFIG_CPU_DCACHE_DISABLE
175	mcr	p15, 0, ip, c7, c10, 4
1761:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
177	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
178	add	r0, r0, #CACHE_DLINESIZE
179	cmp	r0, r1
180	blo	1b
181#endif
182	tst	r2, #VM_EXEC
183#ifndef CONFIG_CPU_ICACHE_DISABLE
184	mcrne	p15, 0, ip, c7, c5, 0		@ invalidate I cache
185#endif
186	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
187	ret	lr
188
189/*
190 *	coherent_kern_range(start, end)
191 *
192 *	Ensure coherency between the Icache and the Dcache in the
193 *	region described by start.  If you have non-snooping
194 *	Harvard caches, you need to implement this function.
195 *
196 *	- start	- virtual start address
197 *	- end	- virtual end address
198 */
199ENTRY(arm1020_coherent_kern_range)
200	/* FALLTRHOUGH */
201
202/*
203 *	coherent_user_range(start, end)
204 *
205 *	Ensure coherency between the Icache and the Dcache in the
206 *	region described by start.  If you have non-snooping
207 *	Harvard caches, you need to implement this function.
208 *
209 *	- start	- virtual start address
210 *	- end	- virtual end address
211 */
212ENTRY(arm1020_coherent_user_range)
213	mov	ip, #0
214	bic	r0, r0, #CACHE_DLINESIZE - 1
215	mcr	p15, 0, ip, c7, c10, 4
2161:
217#ifndef CONFIG_CPU_DCACHE_DISABLE
218	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
219	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
220#endif
221#ifndef CONFIG_CPU_ICACHE_DISABLE
222	mcr	p15, 0, r0, c7, c5, 1		@ invalidate I entry
223#endif
224	add	r0, r0, #CACHE_DLINESIZE
225	cmp	r0, r1
226	blo	1b
227	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
228	mov	r0, #0
229	ret	lr
230
231/*
232 *	flush_kern_dcache_area(void *addr, size_t size)
233 *
234 *	Ensure no D cache aliasing occurs, either with itself or
235 *	the I cache
236 *
237 *	- addr	- kernel address
238 *	- size	- region size
239 */
240ENTRY(arm1020_flush_kern_dcache_area)
241	mov	ip, #0
242#ifndef CONFIG_CPU_DCACHE_DISABLE
243	add	r1, r0, r1
2441:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
245	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
246	add	r0, r0, #CACHE_DLINESIZE
247	cmp	r0, r1
248	blo	1b
249#endif
250	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
251	ret	lr
252
253/*
254 *	dma_inv_range(start, end)
255 *
256 *	Invalidate (discard) the specified virtual address range.
257 *	May not write back any entries.  If 'start' or 'end'
258 *	are not cache line aligned, those lines must be written
259 *	back.
260 *
261 *	- start	- virtual start address
262 *	- end	- virtual end address
263 *
264 * (same as v4wb)
265 */
266arm1020_dma_inv_range:
267	mov	ip, #0
268#ifndef CONFIG_CPU_DCACHE_DISABLE
269	tst	r0, #CACHE_DLINESIZE - 1
270	bic	r0, r0, #CACHE_DLINESIZE - 1
271	mcrne	p15, 0, ip, c7, c10, 4
272	mcrne	p15, 0, r0, c7, c10, 1		@ clean D entry
273	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
274	tst	r1, #CACHE_DLINESIZE - 1
275	mcrne	p15, 0, ip, c7, c10, 4
276	mcrne	p15, 0, r1, c7, c10, 1		@ clean D entry
277	mcrne	p15, 0, ip, c7, c10, 4		@ drain WB
2781:	mcr	p15, 0, r0, c7, c6, 1		@ invalidate D entry
279	add	r0, r0, #CACHE_DLINESIZE
280	cmp	r0, r1
281	blo	1b
282#endif
283	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
284	ret	lr
285
286/*
287 *	dma_clean_range(start, end)
288 *
289 *	Clean the specified virtual address range.
290 *
291 *	- start	- virtual start address
292 *	- end	- virtual end address
293 *
294 * (same as v4wb)
295 */
296arm1020_dma_clean_range:
297	mov	ip, #0
298#ifndef CONFIG_CPU_DCACHE_DISABLE
299	bic	r0, r0, #CACHE_DLINESIZE - 1
3001:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
301	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
302	add	r0, r0, #CACHE_DLINESIZE
303	cmp	r0, r1
304	blo	1b
305#endif
306	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
307	ret	lr
308
309/*
310 *	dma_flush_range(start, end)
311 *
312 *	Clean and invalidate the specified virtual address range.
313 *
314 *	- start	- virtual start address
315 *	- end	- virtual end address
316 */
317ENTRY(arm1020_dma_flush_range)
318	mov	ip, #0
319#ifndef CONFIG_CPU_DCACHE_DISABLE
320	bic	r0, r0, #CACHE_DLINESIZE - 1
321	mcr	p15, 0, ip, c7, c10, 4
3221:	mcr	p15, 0, r0, c7, c14, 1		@ clean+invalidate D entry
323	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
324	add	r0, r0, #CACHE_DLINESIZE
325	cmp	r0, r1
326	blo	1b
327#endif
328	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
329	ret	lr
330
331/*
332 *	dma_map_area(start, size, dir)
333 *	- start	- kernel virtual start address
334 *	- size	- size of region
335 *	- dir	- DMA direction
336 */
337ENTRY(arm1020_dma_map_area)
338	add	r1, r1, r0
339	cmp	r2, #DMA_TO_DEVICE
340	beq	arm1020_dma_clean_range
341	bcs	arm1020_dma_inv_range
342	b	arm1020_dma_flush_range
343ENDPROC(arm1020_dma_map_area)
344
345/*
346 *	dma_unmap_area(start, size, dir)
347 *	- start	- kernel virtual start address
348 *	- size	- size of region
349 *	- dir	- DMA direction
350 */
351ENTRY(arm1020_dma_unmap_area)
352	ret	lr
353ENDPROC(arm1020_dma_unmap_area)
354
355	.globl	arm1020_flush_kern_cache_louis
356	.equ	arm1020_flush_kern_cache_louis, arm1020_flush_kern_cache_all
357
358	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
359	define_cache_functions arm1020
360
361	.align	5
362ENTRY(cpu_arm1020_dcache_clean_area)
363#ifndef CONFIG_CPU_DCACHE_DISABLE
364	mov	ip, #0
3651:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
366	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
367	add	r0, r0, #CACHE_DLINESIZE
368	subs	r1, r1, #CACHE_DLINESIZE
369	bhi	1b
370#endif
371	ret	lr
372
373/* =============================== PageTable ============================== */
374
375/*
376 * cpu_arm1020_switch_mm(pgd)
377 *
378 * Set the translation base pointer to be as described by pgd.
379 *
380 * pgd: new page tables
381 */
382	.align	5
383ENTRY(cpu_arm1020_switch_mm)
384#ifdef CONFIG_MMU
385#ifndef CONFIG_CPU_DCACHE_DISABLE
386	mcr	p15, 0, r3, c7, c10, 4
387	mov	r1, #0xF			@ 16 segments
3881:	mov	r3, #0x3F			@ 64 entries
3892:	mov	ip, r3, LSL #26 		@ shift up entry
390	orr	ip, ip, r1, LSL #5		@ shift in/up index
391	mcr	p15, 0, ip, c7, c14, 2		@ Clean & Inval DCache entry
392	mov	ip, #0
393	mcr	p15, 0, ip, c7, c10, 4
394	subs	r3, r3, #1
395	cmp	r3, #0
396	bge	2b				@ entries 3F to 0
397	subs	r1, r1, #1
398	cmp	r1, #0
399	bge	1b				@ segments 15 to 0
400
401#endif
402	mov	r1, #0
403#ifndef CONFIG_CPU_ICACHE_DISABLE
404	mcr	p15, 0, r1, c7, c5, 0		@ invalidate I cache
405#endif
406	mcr	p15, 0, r1, c7, c10, 4		@ drain WB
407	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
408	mcr	p15, 0, r1, c8, c7, 0		@ invalidate I & D TLBs
409#endif /* CONFIG_MMU */
410	ret	lr
411
412/*
413 * cpu_arm1020_set_pte(ptep, pte)
414 *
415 * Set a PTE and flush it out
416 */
417	.align	5
418ENTRY(cpu_arm1020_set_pte_ext)
419#ifdef CONFIG_MMU
420	armv3_set_pte_ext
421	mov	r0, r0
422#ifndef CONFIG_CPU_DCACHE_DISABLE
423	mcr	p15, 0, r0, c7, c10, 4
424	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
425#endif
426	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
427#endif /* CONFIG_MMU */
428	ret	lr
429
430	.type	__arm1020_setup, #function
431__arm1020_setup:
432	mov	r0, #0
433	mcr	p15, 0, r0, c7, c7		@ invalidate I,D caches on v4
434	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer on v4
435#ifdef CONFIG_MMU
436	mcr	p15, 0, r0, c8, c7		@ invalidate I,D TLBs on v4
437#endif
438
439	adr	r5, arm1020_crval
440	ldmia	r5, {r5, r6}
441	mrc	p15, 0, r0, c1, c0		@ get control register v4
442	bic	r0, r0, r5
443	orr	r0, r0, r6
444#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
445	orr	r0, r0, #0x4000 		@ .R.. .... .... ....
446#endif
447	ret	lr
448	.size	__arm1020_setup, . - __arm1020_setup
449
450	/*
451	 *  R
452	 * .RVI ZFRS BLDP WCAM
453	 * .011 1001 ..11 0101
454	 */
455	.type	arm1020_crval, #object
456arm1020_crval:
457	crval	clear=0x0000593f, mmuset=0x00003935, ucset=0x00001930
458
459	__INITDATA
460	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
461	define_processor_functions arm1020, dabort=v4t_early_abort, pabort=legacy_pabort
462
463
464	.section ".rodata"
465
466	string	cpu_arch_name, "armv5t"
467	string	cpu_elf_name, "v5"
468
469	.type	cpu_arm1020_name, #object
470cpu_arm1020_name:
471	.ascii	"ARM1020"
472#ifndef CONFIG_CPU_ICACHE_DISABLE
473	.ascii	"i"
474#endif
475#ifndef CONFIG_CPU_DCACHE_DISABLE
476	.ascii	"d"
477#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
478	.ascii	"(wt)"
479#else
480	.ascii	"(wb)"
481#endif
482#endif
483#ifndef CONFIG_CPU_BPREDICT_DISABLE
484	.ascii	"B"
485#endif
486#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
487	.ascii	"RR"
488#endif
489	.ascii	"\0"
490	.size	cpu_arm1020_name, . - cpu_arm1020_name
491
492	.align
493
494	.section ".proc.info.init", "a"
495
496	.type	__arm1020_proc_info,#object
497__arm1020_proc_info:
498	.long	0x4104a200			@ ARM 1020T (Architecture v5T)
499	.long	0xff0ffff0
500	.long   PMD_TYPE_SECT | \
501		PMD_SECT_AP_WRITE | \
502		PMD_SECT_AP_READ
503	.long   PMD_TYPE_SECT | \
504		PMD_SECT_AP_WRITE | \
505		PMD_SECT_AP_READ
506	initfn	__arm1020_setup, __arm1020_proc_info
507	.long	cpu_arch_name
508	.long	cpu_elf_name
509	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
510	.long	cpu_arm1020_name
511	.long	arm1020_processor_functions
512	.long	v4wbi_tlb_fns
513	.long	v4wb_user_fns
514	.long	arm1020_cache_fns
515	.size	__arm1020_proc_info, . - __arm1020_proc_info
516