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/pgtable.h>
15#include <asm/assembler.h>
16#include <asm/asm-offsets.h>
17#include <asm/hwcap.h>
18#include <asm/pgtable-hwdef.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

source code of linux/arch/arm/mm/proc-arm1020.S