1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * linux/arch/arm/mm/proc-arm922.S: MMU functions for ARM922
4 *
5 * Copyright (C) 1999,2000 ARM Limited
6 * Copyright (C) 2000 Deep Blue Solutions Ltd.
7 * Copyright (C) 2001 Altera Corporation
8 * hacked for non-paged-MM by Hyok S. Choi, 2003.
9 *
10 * These are the low level assembler for performing cache and TLB
11 * functions on the arm922.
12 *
13 * CONFIG_CPU_ARM922_CPU_IDLE -> nohlt
14 */
15 #include <linux/linkage.h>
16 #include <linux/init.h>
17 #include <linux/cfi_types.h>
18 #include <linux/pgtable.h>
19 #include <asm/assembler.h>
20 #include <asm/hwcap.h>
21 #include <asm/pgtable-hwdef.h>
22 #include <asm/page.h>
23 #include <asm/ptrace.h>
24 #include "proc-macros.S"
25
26 /*
27 * The size of one data cache line.
28 */
29 #define CACHE_DLINESIZE 32
30
31 /*
32 * The number of data cache segments.
33 */
34 #define CACHE_DSEGMENTS 4
35
36 /*
37 * The number of lines in a cache segment.
38 */
39 #define CACHE_DENTRIES 64
40
41 /*
42 * This is the size at which it becomes more efficient to
43 * clean the whole cache, rather than using the individual
44 * cache line maintenance instructions. (I think this should
45 * be 32768).
46 */
47 #define CACHE_DLIMIT 8192
48
49
50 .text
51 /*
52 * cpu_arm922_proc_init()
53 */
54 SYM_TYPED_FUNC_START(cpu_arm922_proc_init)
55 ret lr
56 SYM_FUNC_END(cpu_arm922_proc_init)
57
58 /*
59 * cpu_arm922_proc_fin()
60 */
61 SYM_TYPED_FUNC_START(cpu_arm922_proc_fin)
62 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
63 bic r0, r0, #0x1000 @ ...i............
64 bic r0, r0, #0x000e @ ............wca.
65 mcr p15, 0, r0, c1, c0, 0 @ disable caches
66 ret lr
67 SYM_FUNC_END(cpu_arm922_proc_fin)
68
69 /*
70 * cpu_arm922_reset(loc)
71 *
72 * Perform a soft reset of the system. Put the CPU into the
73 * same state as it would be if it had been reset, and branch
74 * to what would be the reset vector.
75 *
76 * loc: location to jump to for soft reset
77 */
78 .align 5
79 .pushsection .idmap.text, "ax"
80 SYM_TYPED_FUNC_START(cpu_arm922_reset)
81 mov ip, #0
82 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
83 mcr p15, 0, ip, c7, c10, 4 @ drain WB
84 #ifdef CONFIG_MMU
85 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
86 #endif
87 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
88 bic ip, ip, #0x000f @ ............wcam
89 bic ip, ip, #0x1100 @ ...i...s........
90 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
91 ret r0
92 SYM_FUNC_END(cpu_arm922_reset)
93 .popsection
94
95 /*
96 * cpu_arm922_do_idle()
97 */
98 .align 5
99 SYM_TYPED_FUNC_START(cpu_arm922_do_idle)
100 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
101 ret lr
102 SYM_FUNC_END(cpu_arm922_do_idle)
103
104 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
105
106 /*
107 * flush_icache_all()
108 *
109 * Unconditionally clean and invalidate the entire icache.
110 */
111 SYM_TYPED_FUNC_START(arm922_flush_icache_all)
112 mov r0, #0
113 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
114 ret lr
115 SYM_FUNC_END(arm922_flush_icache_all)
116
117 /*
118 * flush_user_cache_all()
119 *
120 * Clean and invalidate all cache entries in a particular
121 * address space.
122 */
123 SYM_FUNC_ALIAS(arm922_flush_user_cache_all, arm922_flush_kern_cache_all)
124
125 /*
126 * flush_kern_cache_all()
127 *
128 * Clean and invalidate the entire cache.
129 */
130 SYM_TYPED_FUNC_START(arm922_flush_kern_cache_all)
131 mov r2, #VM_EXEC
132 mov ip, #0
133 __flush_whole_cache:
134 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
135 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
136 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
137 subs r3, r3, #1 << 26
138 bcs 2b @ entries 63 to 0
139 subs r1, r1, #1 << 5
140 bcs 1b @ segments 7 to 0
141 tst r2, #VM_EXEC
142 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
143 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
144 ret lr
145 SYM_FUNC_END(arm922_flush_kern_cache_all)
146
147 /*
148 * flush_user_cache_range(start, end, flags)
149 *
150 * Clean and invalidate a range of cache entries in the
151 * specified address range.
152 *
153 * - start - start address (inclusive)
154 * - end - end address (exclusive)
155 * - flags - vm_flags describing address space
156 */
157 SYM_TYPED_FUNC_START(arm922_flush_user_cache_range)
158 mov ip, #0
159 sub r3, r1, r0 @ calculate total size
160 cmp r3, #CACHE_DLIMIT
161 bhs __flush_whole_cache
162
163 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
164 tst r2, #VM_EXEC
165 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
166 add r0, r0, #CACHE_DLINESIZE
167 cmp r0, r1
168 blo 1b
169 tst r2, #VM_EXEC
170 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
171 ret lr
172 SYM_FUNC_END(arm922_flush_user_cache_range)
173
174 /*
175 * coherent_kern_range(start, end)
176 *
177 * Ensure coherency between the Icache and the Dcache in the
178 * region described by start, end. If you have non-snooping
179 * Harvard caches, you need to implement this function.
180 *
181 * - start - virtual start address
182 * - end - virtual end address
183 */
184 SYM_TYPED_FUNC_START(arm922_coherent_kern_range)
185 #ifdef CONFIG_CFI_CLANG /* Fallthrough if !CFI */
186 b arm922_coherent_user_range
187 #endif
188 SYM_FUNC_END(arm922_coherent_kern_range)
189
190 /*
191 * coherent_user_range(start, end)
192 *
193 * Ensure coherency between the Icache and the Dcache in the
194 * region described by start, end. If you have non-snooping
195 * Harvard caches, you need to implement this function.
196 *
197 * - start - virtual start address
198 * - end - virtual end address
199 */
200 SYM_TYPED_FUNC_START(arm922_coherent_user_range)
201 bic r0, r0, #CACHE_DLINESIZE - 1
202 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
203 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
204 add r0, r0, #CACHE_DLINESIZE
205 cmp r0, r1
206 blo 1b
207 mcr p15, 0, r0, c7, c10, 4 @ drain WB
208 mov r0, #0
209 ret lr
210 SYM_FUNC_END(arm922_coherent_user_range)
211
212 /*
213 * flush_kern_dcache_area(void *addr, size_t size)
214 *
215 * Ensure no D cache aliasing occurs, either with itself or
216 * the I cache
217 *
218 * - addr - kernel address
219 * - size - region size
220 */
221 SYM_TYPED_FUNC_START(arm922_flush_kern_dcache_area)
222 add r1, r0, r1
223 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
224 add r0, r0, #CACHE_DLINESIZE
225 cmp r0, r1
226 blo 1b
227 mov r0, #0
228 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
229 mcr p15, 0, r0, c7, c10, 4 @ drain WB
230 ret lr
231 SYM_FUNC_END(arm922_flush_kern_dcache_area)
232
233 /*
234 * dma_inv_range(start, end)
235 *
236 * Invalidate (discard) the specified virtual address range.
237 * May not write back any entries. If 'start' or 'end'
238 * are not cache line aligned, those lines must be written
239 * back.
240 *
241 * - start - virtual start address
242 * - end - virtual end address
243 *
244 * (same as v4wb)
245 */
246 arm922_dma_inv_range:
247 tst r0, #CACHE_DLINESIZE - 1
248 bic r0, r0, #CACHE_DLINESIZE - 1
249 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
250 tst r1, #CACHE_DLINESIZE - 1
251 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
252 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
253 add r0, r0, #CACHE_DLINESIZE
254 cmp r0, r1
255 blo 1b
256 mcr p15, 0, r0, c7, c10, 4 @ drain WB
257 ret lr
258
259 /*
260 * dma_clean_range(start, end)
261 *
262 * Clean the specified virtual address range.
263 *
264 * - start - virtual start address
265 * - end - virtual end address
266 *
267 * (same as v4wb)
268 */
269 arm922_dma_clean_range:
270 bic r0, r0, #CACHE_DLINESIZE - 1
271 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
272 add r0, r0, #CACHE_DLINESIZE
273 cmp r0, r1
274 blo 1b
275 mcr p15, 0, r0, c7, c10, 4 @ drain WB
276 ret lr
277
278 /*
279 * dma_flush_range(start, end)
280 *
281 * Clean and invalidate the specified virtual address range.
282 *
283 * - start - virtual start address
284 * - end - virtual end address
285 */
286 SYM_TYPED_FUNC_START(arm922_dma_flush_range)
287 bic r0, r0, #CACHE_DLINESIZE - 1
288 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
289 add r0, r0, #CACHE_DLINESIZE
290 cmp r0, r1
291 blo 1b
292 mcr p15, 0, r0, c7, c10, 4 @ drain WB
293 ret lr
294 SYM_FUNC_END(arm922_dma_flush_range)
295
296 /*
297 * dma_map_area(start, size, dir)
298 * - start - kernel virtual start address
299 * - size - size of region
300 * - dir - DMA direction
301 */
302 SYM_TYPED_FUNC_START(arm922_dma_map_area)
303 add r1, r1, r0
304 cmp r2, #DMA_TO_DEVICE
305 beq arm922_dma_clean_range
306 bcs arm922_dma_inv_range
307 b arm922_dma_flush_range
308 SYM_FUNC_END(arm922_dma_map_area)
309
310 /*
311 * dma_unmap_area(start, size, dir)
312 * - start - kernel virtual start address
313 * - size - size of region
314 * - dir - DMA direction
315 */
316 SYM_TYPED_FUNC_START(arm922_dma_unmap_area)
317 ret lr
318 SYM_FUNC_END(arm922_dma_unmap_area)
319
320 #endif /* !CONFIG_CPU_DCACHE_WRITETHROUGH */
321
322 SYM_TYPED_FUNC_START(cpu_arm922_dcache_clean_area)
323 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
324 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
325 add r0, r0, #CACHE_DLINESIZE
326 subs r1, r1, #CACHE_DLINESIZE
327 bhi 1b
328 #endif
329 ret lr
330 SYM_FUNC_END(cpu_arm922_dcache_clean_area)
331
332 /* =============================== PageTable ============================== */
333
334 /*
335 * cpu_arm922_switch_mm(pgd)
336 *
337 * Set the translation base pointer to be as described by pgd.
338 *
339 * pgd: new page tables
340 */
341 .align 5
342 SYM_TYPED_FUNC_START(cpu_arm922_switch_mm)
343 #ifdef CONFIG_MMU
344 mov ip, #0
345 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
346 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
347 #else
348 @ && 'Clean & Invalidate whole DCache'
349 @ && Re-written to use Index Ops.
350 @ && Uses registers r1, r3 and ip
351
352 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 4 segments
353 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
354 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
355 subs r3, r3, #1 << 26
356 bcs 2b @ entries 63 to 0
357 subs r1, r1, #1 << 5
358 bcs 1b @ segments 7 to 0
359 #endif
360 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
361 mcr p15, 0, ip, c7, c10, 4 @ drain WB
362 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
363 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
364 #endif
365 ret lr
366 SYM_FUNC_END(cpu_arm922_switch_mm)
367
368 /*
369 * cpu_arm922_set_pte_ext(ptep, pte, ext)
370 *
371 * Set a PTE and flush it out
372 */
373 .align 5
374 SYM_TYPED_FUNC_START(cpu_arm922_set_pte_ext)
375 #ifdef CONFIG_MMU
376 armv3_set_pte_ext
377 mov r0, r0
378 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
379 mcr p15, 0, r0, c7, c10, 4 @ drain WB
380 #endif /* CONFIG_MMU */
381 ret lr
382 SYM_FUNC_END(cpu_arm922_set_pte_ext)
383
384 .type __arm922_setup, #function
385 __arm922_setup:
386 mov r0, #0
387 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
388 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
389 #ifdef CONFIG_MMU
390 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
391 #endif
392 adr r5, arm922_crval
393 ldmia r5, {r5, r6}
394 mrc p15, 0, r0, c1, c0 @ get control register v4
395 bic r0, r0, r5
396 orr r0, r0, r6
397 ret lr
398 .size __arm922_setup, . - __arm922_setup
399
400 /*
401 * R
402 * .RVI ZFRS BLDP WCAM
403 * ..11 0001 ..11 0101
404 *
405 */
406 .type arm922_crval, #object
407 arm922_crval:
408 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
409
410 __INITDATA
411 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
412 define_processor_functions arm922, dabort=v4t_early_abort, pabort=legacy_pabort
413
414 .section ".rodata"
415
416 string cpu_arch_name, "armv4t"
417 string cpu_elf_name, "v4"
418 string cpu_arm922_name, "ARM922T"
419
420 .align
421
422 .section ".proc.info.init", "a"
423
424 .type __arm922_proc_info,#object
425 __arm922_proc_info:
426 .long 0x41009220
427 .long 0xff00fff0
428 .long PMD_TYPE_SECT | \
429 PMD_SECT_BUFFERABLE | \
430 PMD_SECT_CACHEABLE | \
431 PMD_BIT4 | \
432 PMD_SECT_AP_WRITE | \
433 PMD_SECT_AP_READ
434 .long PMD_TYPE_SECT | \
435 PMD_BIT4 | \
436 PMD_SECT_AP_WRITE | \
437 PMD_SECT_AP_READ
438 initfn __arm922_setup, __arm922_proc_info
439 .long cpu_arch_name
440 .long cpu_elf_name
441 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
442 .long cpu_arm922_name
443 .long arm922_processor_functions
444 .long v4wbi_tlb_fns
445 .long v4wb_user_fns
446 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
447 .long arm922_cache_fns
448 #else
449 .long v4wt_cache_fns
450 #endif
451 .size __arm922_proc_info, . - __arm922_proc_info
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.