| blob | ca2c7ca8af21468213173978d41daab45fe0f97e |
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 <asm/assembler.h>
18 #include <asm/hwcap.h>
19 #include <asm/pgtable-hwdef.h>
20 #include <asm/pgtable.h>
21 #include <asm/page.h>
22 #include <asm/ptrace.h>
23 #include "proc-macros.S"
25 /*
26 * The size of one data cache line.
27 */
28 #define CACHE_DLINESIZE 32
30 /*
31 * The number of data cache segments.
32 */
33 #define CACHE_DSEGMENTS 4
35 /*
36 * The number of lines in a cache segment.
37 */
38 #define CACHE_DENTRIES 64
40 /*
41 * This is the size at which it becomes more efficient to
42 * clean the whole cache, rather than using the individual
43 * cache line maintenance instructions. (I think this should
44 * be 32768).
45 */
46 #define CACHE_DLIMIT 8192
49 .text
50 /*
51 * cpu_arm922_proc_init()
52 */
53 ENTRY(cpu_arm922_proc_init)
54 ret lr
56 /*
57 * cpu_arm922_proc_fin()
58 */
59 ENTRY(cpu_arm922_proc_fin)
60 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
61 bic r0, r0, #0x1000 @ ...i............
62 bic r0, r0, #0x000e @ ............wca.
63 mcr p15, 0, r0, c1, c0, 0 @ disable caches
64 ret lr
66 /*
67 * cpu_arm922_reset(loc)
68 *
69 * Perform a soft reset of the system. Put the CPU into the
70 * same state as it would be if it had been reset, and branch
71 * to what would be the reset vector.
72 *
73 * loc: location to jump to for soft reset
74 */
75 .align 5
76 .pushsection .idmap.text, "ax"
77 ENTRY(cpu_arm922_reset)
78 mov ip, #0
79 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
80 mcr p15, 0, ip, c7, c10, 4 @ drain WB
81 #ifdef CONFIG_MMU
82 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
83 #endif
84 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
85 bic ip, ip, #0x000f @ ............wcam
86 bic ip, ip, #0x1100 @ ...i...s........
87 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
88 ret r0
89 ENDPROC(cpu_arm922_reset)
90 .popsection
92 /*
93 * cpu_arm922_do_idle()
94 */
95 .align 5
96 ENTRY(cpu_arm922_do_idle)
97 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
98 ret lr
101 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
103 /*
104 * flush_icache_all()
105 *
106 * Unconditionally clean and invalidate the entire icache.
107 */
108 ENTRY(arm922_flush_icache_all)
109 mov r0, #0
110 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
111 ret lr
112 ENDPROC(arm922_flush_icache_all)
114 /*
115 * flush_user_cache_all()
116 *
117 * Clean and invalidate all cache entries in a particular
118 * address space.
119 */
120 ENTRY(arm922_flush_user_cache_all)
121 /* FALLTHROUGH */
123 /*
124 * flush_kern_cache_all()
125 *
126 * Clean and invalidate the entire cache.
127 */
128 ENTRY(arm922_flush_kern_cache_all)
129 mov r2, #VM_EXEC
130 mov ip, #0
131 __flush_whole_cache:
132 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
133 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
134 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
135 subs r3, r3, #1 << 26
136 bcs 2b @ entries 63 to 0
137 subs r1, r1, #1 << 5
138 bcs 1b @ segments 7 to 0
139 tst r2, #VM_EXEC
140 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
141 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
142 ret lr
144 /*
145 * flush_user_cache_range(start, end, flags)
146 *
147 * Clean and invalidate a range of cache entries in the
148 * specified address range.
149 *
150 * - start - start address (inclusive)
151 * - end - end address (exclusive)
152 * - flags - vm_flags describing address space
153 */
154 ENTRY(arm922_flush_user_cache_range)
155 mov ip, #0
156 sub r3, r1, r0 @ calculate total size
157 cmp r3, #CACHE_DLIMIT
158 bhs __flush_whole_cache
160 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
161 tst r2, #VM_EXEC
162 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
163 add r0, r0, #CACHE_DLINESIZE
164 cmp r0, r1
165 blo 1b
166 tst r2, #VM_EXEC
167 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
168 ret lr
170 /*
171 * coherent_kern_range(start, end)
172 *
173 * Ensure coherency between the Icache and the Dcache in the
174 * region described by start, end. If you have non-snooping
175 * Harvard caches, you need to implement this function.
176 *
177 * - start - virtual start address
178 * - end - virtual end address
179 */
180 ENTRY(arm922_coherent_kern_range)
181 /* FALLTHROUGH */
183 /*
184 * coherent_user_range(start, end)
185 *
186 * Ensure coherency between the Icache and the Dcache in the
187 * region described by start, end. If you have non-snooping
188 * Harvard caches, you need to implement this function.
189 *
190 * - start - virtual start address
191 * - end - virtual end address
192 */
193 ENTRY(arm922_coherent_user_range)
194 bic r0, r0, #CACHE_DLINESIZE - 1
195 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
196 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
197 add r0, r0, #CACHE_DLINESIZE
198 cmp r0, r1
199 blo 1b
200 mcr p15, 0, r0, c7, c10, 4 @ drain WB
201 mov r0, #0
202 ret lr
204 /*
205 * flush_kern_dcache_area(void *addr, size_t size)
206 *
207 * Ensure no D cache aliasing occurs, either with itself or
208 * the I cache
209 *
210 * - addr - kernel address
211 * - size - region size
212 */
213 ENTRY(arm922_flush_kern_dcache_area)
214 add r1, r0, r1
215 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
216 add r0, r0, #CACHE_DLINESIZE
217 cmp r0, r1
218 blo 1b
219 mov r0, #0
220 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
221 mcr p15, 0, r0, c7, c10, 4 @ drain WB
222 ret lr
224 /*
225 * dma_inv_range(start, end)
226 *
227 * Invalidate (discard) the specified virtual address range.
228 * May not write back any entries. If 'start' or 'end'
229 * are not cache line aligned, those lines must be written
230 * back.
231 *
232 * - start - virtual start address
233 * - end - virtual end address
234 *
235 * (same as v4wb)
236 */
237 arm922_dma_inv_range:
238 tst r0, #CACHE_DLINESIZE - 1
239 bic r0, r0, #CACHE_DLINESIZE - 1
240 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
241 tst r1, #CACHE_DLINESIZE - 1
242 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
243 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
244 add r0, r0, #CACHE_DLINESIZE
245 cmp r0, r1
246 blo 1b
247 mcr p15, 0, r0, c7, c10, 4 @ drain WB
248 ret lr
250 /*
251 * dma_clean_range(start, end)
252 *
253 * Clean the specified virtual address range.
254 *
255 * - start - virtual start address
256 * - end - virtual end address
257 *
258 * (same as v4wb)
259 */
260 arm922_dma_clean_range:
261 bic r0, r0, #CACHE_DLINESIZE - 1
262 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
263 add r0, r0, #CACHE_DLINESIZE
264 cmp r0, r1
265 blo 1b
266 mcr p15, 0, r0, c7, c10, 4 @ drain WB
267 ret lr
269 /*
270 * dma_flush_range(start, end)
271 *
272 * Clean and invalidate the specified virtual address range.
273 *
274 * - start - virtual start address
275 * - end - virtual end address
276 */
277 ENTRY(arm922_dma_flush_range)
278 bic r0, r0, #CACHE_DLINESIZE - 1
279 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
280 add r0, r0, #CACHE_DLINESIZE
281 cmp r0, r1
282 blo 1b
283 mcr p15, 0, r0, c7, c10, 4 @ drain WB
284 ret lr
286 /*
287 * dma_map_area(start, size, dir)
288 * - start - kernel virtual start address
289 * - size - size of region
290 * - dir - DMA direction
291 */
292 ENTRY(arm922_dma_map_area)
293 add r1, r1, r0
294 cmp r2, #DMA_TO_DEVICE
295 beq arm922_dma_clean_range
296 bcs arm922_dma_inv_range
297 b arm922_dma_flush_range
298 ENDPROC(arm922_dma_map_area)
300 /*
301 * dma_unmap_area(start, size, dir)
302 * - start - kernel virtual start address
303 * - size - size of region
304 * - dir - DMA direction
305 */
306 ENTRY(arm922_dma_unmap_area)
307 ret lr
308 ENDPROC(arm922_dma_unmap_area)
310 .globl arm922_flush_kern_cache_louis
311 .equ arm922_flush_kern_cache_louis, arm922_flush_kern_cache_all
313 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
314 define_cache_functions arm922
315 #endif
318 ENTRY(cpu_arm922_dcache_clean_area)
319 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
320 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
321 add r0, r0, #CACHE_DLINESIZE
322 subs r1, r1, #CACHE_DLINESIZE
323 bhi 1b
324 #endif
325 ret lr
327 /* =============================== PageTable ============================== */
329 /*
330 * cpu_arm922_switch_mm(pgd)
331 *
332 * Set the translation base pointer to be as described by pgd.
333 *
334 * pgd: new page tables
335 */
336 .align 5
337 ENTRY(cpu_arm922_switch_mm)
338 #ifdef CONFIG_MMU
339 mov ip, #0
340 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
341 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
342 #else
343 @ && 'Clean & Invalidate whole DCache'
344 @ && Re-written to use Index Ops.
345 @ && Uses registers r1, r3 and ip
347 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 4 segments
348 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
349 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
350 subs r3, r3, #1 << 26
351 bcs 2b @ entries 63 to 0
352 subs r1, r1, #1 << 5
353 bcs 1b @ segments 7 to 0
354 #endif
355 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
356 mcr p15, 0, ip, c7, c10, 4 @ drain WB
357 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
358 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
359 #endif
360 ret lr
362 /*
363 * cpu_arm922_set_pte_ext(ptep, pte, ext)
364 *
365 * Set a PTE and flush it out
366 */
367 .align 5
368 ENTRY(cpu_arm922_set_pte_ext)
369 #ifdef CONFIG_MMU
370 armv3_set_pte_ext
371 mov r0, r0
372 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
373 mcr p15, 0, r0, c7, c10, 4 @ drain WB
374 #endif /* CONFIG_MMU */
375 ret lr
377 .type __arm922_setup, #function
378 __arm922_setup:
379 mov r0, #0
380 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
381 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
382 #ifdef CONFIG_MMU
383 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
384 #endif
385 adr r5, arm922_crval
386 ldmia r5, {r5, r6}
387 mrc p15, 0, r0, c1, c0 @ get control register v4
388 bic r0, r0, r5
389 orr r0, r0, r6
390 ret lr
391 .size __arm922_setup, . - __arm922_setup
393 /*
394 * R
395 * .RVI ZFRS BLDP WCAM
396 * ..11 0001 ..11 0101
397 *
398 */
399 .type arm922_crval, #object
400 arm922_crval:
401 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
403 __INITDATA
404 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
405 define_processor_functions arm922, dabort=v4t_early_abort, pabort=legacy_pabort
407 .section ".rodata"
409 string cpu_arch_name, "armv4t"
410 string cpu_elf_name, "v4"
411 string cpu_arm922_name, "ARM922T"
413 .align
415 .section ".proc.info.init", "a"
417 .type __arm922_proc_info,#object
418 __arm922_proc_info:
419 .long 0x41009220
420 .long 0xff00fff0
421 .long PMD_TYPE_SECT | \
422 PMD_SECT_BUFFERABLE | \
423 PMD_SECT_CACHEABLE | \
424 PMD_BIT4 | \
425 PMD_SECT_AP_WRITE | \
426 PMD_SECT_AP_READ
427 .long PMD_TYPE_SECT | \
428 PMD_BIT4 | \
429 PMD_SECT_AP_WRITE | \
430 PMD_SECT_AP_READ
431 initfn __arm922_setup, __arm922_proc_info
432 .long cpu_arch_name
433 .long cpu_elf_name
434 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
435 .long cpu_arm922_name
436 .long arm922_processor_functions
437 .long v4wbi_tlb_fns
438 .long v4wb_user_fns
439 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
440 .long arm922_cache_fns
441 #else
442 .long v4wt_cache_fns
443 #endif
444 .size __arm922_proc_info, . - __arm922_proc_info