| blob | a17f79e0199c9ea0160ff2a987267e18fc26dd0b |
1 /*
2 * linux/arch/arm/mm/proc-arm920.S: MMU functions for ARM920
3 *
4 * Copyright (C) 1999,2000 ARM Limited
5 * Copyright (C) 2000 Deep Blue Solutions Ltd.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 *
22 * These are the low level assembler for performing cache and TLB
23 * functions on the arm920.
24 *
25 * CONFIG_CPU_ARM920_CPU_IDLE -> nohlt
26 */
27 #include <linux/linkage.h>
28 #include <linux/config.h>
29 #include <linux/init.h>
30 #include <asm/assembler.h>
31 #include <asm/pgtable-hwdef.h>
32 #include <asm/pgtable.h>
33 #include <asm/procinfo.h>
34 #include <asm/page.h>
35 #include <asm/ptrace.h>
36 #include "proc-macros.S"
38 /*
39 * The size of one data cache line.
40 */
41 #define CACHE_DLINESIZE 32
43 /*
44 * The number of data cache segments.
45 */
46 #define CACHE_DSEGMENTS 8
48 /*
49 * The number of lines in a cache segment.
50 */
51 #define CACHE_DENTRIES 64
53 /*
54 * This is the size at which it becomes more efficient to
55 * clean the whole cache, rather than using the individual
56 * cache line maintainence instructions.
57 */
58 #define CACHE_DLIMIT 65536
61 .text
62 /*
63 * cpu_arm920_proc_init()
64 */
65 ENTRY(cpu_arm920_proc_init)
66 mov pc, lr
68 /*
69 * cpu_arm920_proc_fin()
70 */
71 ENTRY(cpu_arm920_proc_fin)
72 stmfd sp!, {lr}
73 mov ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
74 msr cpsr_c, ip
75 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
76 bl arm920_flush_kern_cache_all
77 #else
78 bl v4wt_flush_kern_cache_all
79 #endif
80 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
81 bic r0, r0, #0x1000 @ ...i............
82 bic r0, r0, #0x000e @ ............wca.
83 mcr p15, 0, r0, c1, c0, 0 @ disable caches
84 ldmfd sp!, {pc}
86 /*
87 * cpu_arm920_reset(loc)
88 *
89 * Perform a soft reset of the system. Put the CPU into the
90 * same state as it would be if it had been reset, and branch
91 * to what would be the reset vector.
92 *
93 * loc: location to jump to for soft reset
94 */
95 .align 5
96 ENTRY(cpu_arm920_reset)
97 mov ip, #0
98 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
99 mcr p15, 0, ip, c7, c10, 4 @ drain WB
100 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
101 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
102 bic ip, ip, #0x000f @ ............wcam
103 bic ip, ip, #0x1100 @ ...i...s........
104 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
105 mov pc, r0
107 /*
108 * cpu_arm920_do_idle()
109 */
110 .align 5
111 ENTRY(cpu_arm920_do_idle)
112 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
113 mov pc, lr
116 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
118 /*
119 * flush_user_cache_all()
120 *
121 * Invalidate all cache entries in a particular address
122 * space.
123 */
124 ENTRY(arm920_flush_user_cache_all)
125 /* FALLTHROUGH */
127 /*
128 * flush_kern_cache_all()
129 *
130 * Clean and invalidate the entire cache.
131 */
132 ENTRY(arm920_flush_kern_cache_all)
133 mov r2, #VM_EXEC
134 mov ip, #0
135 __flush_whole_cache:
136 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
137 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
138 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
139 subs r3, r3, #1 << 26
140 bcs 2b @ entries 63 to 0
141 subs r1, r1, #1 << 5
142 bcs 1b @ segments 7 to 0
143 tst r2, #VM_EXEC
144 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
145 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
146 mov pc, lr
148 /*
149 * flush_user_cache_range(start, end, flags)
150 *
151 * Invalidate a range of cache entries in the specified
152 * address space.
153 *
154 * - start - start address (inclusive)
155 * - end - end address (exclusive)
156 * - flags - vm_flags for address space
157 */
158 ENTRY(arm920_flush_user_cache_range)
159 mov ip, #0
160 sub r3, r1, r0 @ calculate total size
161 cmp r3, #CACHE_DLIMIT
162 bhs __flush_whole_cache
164 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
165 tst r2, #VM_EXEC
166 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
167 add r0, r0, #CACHE_DLINESIZE
168 cmp r0, r1
169 blo 1b
170 tst r2, #VM_EXEC
171 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
172 mov pc, lr
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 ENTRY(arm920_coherent_kern_range)
185 /* FALLTHROUGH */
187 /*
188 * coherent_user_range(start, end)
189 *
190 * Ensure coherency between the Icache and the Dcache in the
191 * region described by start, end. If you have non-snooping
192 * Harvard caches, you need to implement this function.
193 *
194 * - start - virtual start address
195 * - end - virtual end address
196 */
197 ENTRY(arm920_coherent_user_range)
198 bic r0, r0, #CACHE_DLINESIZE - 1
199 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
200 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
201 add r0, r0, #CACHE_DLINESIZE
202 cmp r0, r1
203 blo 1b
204 mcr p15, 0, r0, c7, c10, 4 @ drain WB
205 mov pc, lr
207 /*
208 * flush_kern_dcache_page(void *page)
209 *
210 * Ensure no D cache aliasing occurs, either with itself or
211 * the I cache
212 *
213 * - addr - page aligned address
214 */
215 ENTRY(arm920_flush_kern_dcache_page)
216 add r1, r0, #PAGE_SZ
217 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
218 add r0, r0, #CACHE_DLINESIZE
219 cmp r0, r1
220 blo 1b
221 mov r0, #0
222 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
223 mcr p15, 0, r0, c7, c10, 4 @ drain WB
224 mov pc, lr
226 /*
227 * dma_inv_range(start, end)
228 *
229 * Invalidate (discard) the specified virtual address range.
230 * May not write back any entries. If 'start' or 'end'
231 * are not cache line aligned, those lines must be written
232 * back.
233 *
234 * - start - virtual start address
235 * - end - virtual end address
236 *
237 * (same as v4wb)
238 */
239 ENTRY(arm920_dma_inv_range)
240 tst r0, #CACHE_DLINESIZE - 1
241 bic r0, r0, #CACHE_DLINESIZE - 1
242 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
243 tst r1, #CACHE_DLINESIZE - 1
244 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
245 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
246 add r0, r0, #CACHE_DLINESIZE
247 cmp r0, r1
248 blo 1b
249 mcr p15, 0, r0, c7, c10, 4 @ drain WB
250 mov pc, lr
252 /*
253 * dma_clean_range(start, end)
254 *
255 * Clean the specified virtual address range.
256 *
257 * - start - virtual start address
258 * - end - virtual end address
259 *
260 * (same as v4wb)
261 */
262 ENTRY(arm920_dma_clean_range)
263 bic r0, r0, #CACHE_DLINESIZE - 1
264 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
265 add r0, r0, #CACHE_DLINESIZE
266 cmp r0, r1
267 blo 1b
268 mcr p15, 0, r0, c7, c10, 4 @ drain WB
269 mov pc, lr
271 /*
272 * dma_flush_range(start, end)
273 *
274 * Clean and invalidate the specified virtual address range.
275 *
276 * - start - virtual start address
277 * - end - virtual end address
278 */
279 ENTRY(arm920_dma_flush_range)
280 bic r0, r0, #CACHE_DLINESIZE - 1
281 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
282 add r0, r0, #CACHE_DLINESIZE
283 cmp r0, r1
284 blo 1b
285 mcr p15, 0, r0, c7, c10, 4 @ drain WB
286 mov pc, lr
288 ENTRY(arm920_cache_fns)
289 .long arm920_flush_kern_cache_all
290 .long arm920_flush_user_cache_all
291 .long arm920_flush_user_cache_range
292 .long arm920_coherent_kern_range
293 .long arm920_coherent_user_range
294 .long arm920_flush_kern_dcache_page
295 .long arm920_dma_inv_range
296 .long arm920_dma_clean_range
297 .long arm920_dma_flush_range
299 #endif
302 ENTRY(cpu_arm920_dcache_clean_area)
303 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
304 add r0, r0, #CACHE_DLINESIZE
305 subs r1, r1, #CACHE_DLINESIZE
306 bhi 1b
307 mov pc, lr
309 /* =============================== PageTable ============================== */
311 /*
312 * cpu_arm920_switch_mm(pgd)
313 *
314 * Set the translation base pointer to be as described by pgd.
315 *
316 * pgd: new page tables
317 */
318 .align 5
319 ENTRY(cpu_arm920_switch_mm)
320 mov ip, #0
321 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
322 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
323 #else
324 @ && 'Clean & Invalidate whole DCache'
325 @ && Re-written to use Index Ops.
326 @ && Uses registers r1, r3 and ip
328 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
329 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
330 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
331 subs r3, r3, #1 << 26
332 bcs 2b @ entries 63 to 0
333 subs r1, r1, #1 << 5
334 bcs 1b @ segments 7 to 0
335 #endif
336 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
337 mcr p15, 0, ip, c7, c10, 4 @ drain WB
338 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
339 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
340 mov pc, lr
342 /*
343 * cpu_arm920_set_pte(ptep, pte)
344 *
345 * Set a PTE and flush it out
346 */
347 .align 5
348 ENTRY(cpu_arm920_set_pte)
349 str r1, [r0], #-2048 @ linux version
351 eor r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
353 bic r2, r1, #PTE_SMALL_AP_MASK
354 bic r2, r2, #PTE_TYPE_MASK
355 orr r2, r2, #PTE_TYPE_SMALL
357 tst r1, #L_PTE_USER @ User?
358 orrne r2, r2, #PTE_SMALL_AP_URO_SRW
360 tst r1, #L_PTE_WRITE | L_PTE_DIRTY @ Write and Dirty?
361 orreq r2, r2, #PTE_SMALL_AP_UNO_SRW
363 tst r1, #L_PTE_PRESENT | L_PTE_YOUNG @ Present and Young?
364 movne r2, #0
366 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
367 eor r3, r2, #0x0a @ C & small page?
368 tst r3, #0x0b
369 biceq r2, r2, #4
370 #endif
371 str r2, [r0] @ hardware version
372 mov r0, r0
373 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
374 mcr p15, 0, r0, c7, c10, 4 @ drain WB
375 mov pc, lr
377 __INIT
379 .type __arm920_setup, #function
380 __arm920_setup:
381 mov r0, #0
382 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
383 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
384 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
385 mrc p15, 0, r0, c1, c0 @ get control register v4
386 ldr r5, arm920_cr1_clear
387 bic r0, r0, r5
388 ldr r5, arm920_cr1_set
389 orr r0, r0, r5
390 mov pc, lr
391 .size __arm920_setup, . - __arm920_setup
393 /*
394 * R
395 * .RVI ZFRS BLDP WCAM
396 * ..11 0001 ..11 0101
397 *
398 */
399 .type arm920_cr1_clear, #object
400 .type arm920_cr1_set, #object
401 arm920_cr1_clear:
402 .word 0x3f3f
403 arm920_cr1_set:
404 .word 0x3135
406 __INITDATA
408 /*
409 * Purpose : Function pointers used to access above functions - all calls
410 * come through these
411 */
412 .type arm920_processor_functions, #object
413 arm920_processor_functions:
414 .word v4t_early_abort
415 .word cpu_arm920_proc_init
416 .word cpu_arm920_proc_fin
417 .word cpu_arm920_reset
418 .word cpu_arm920_do_idle
419 .word cpu_arm920_dcache_clean_area
420 .word cpu_arm920_switch_mm
421 .word cpu_arm920_set_pte
422 .size arm920_processor_functions, . - arm920_processor_functions
424 .section ".rodata"
426 .type cpu_arch_name, #object
427 cpu_arch_name:
428 .asciz "armv4t"
429 .size cpu_arch_name, . - cpu_arch_name
431 .type cpu_elf_name, #object
432 cpu_elf_name:
433 .asciz "v4"
434 .size cpu_elf_name, . - cpu_elf_name
436 .type cpu_arm920_name, #object
437 cpu_arm920_name:
438 .ascii "ARM920T"
439 #ifndef CONFIG_CPU_ICACHE_DISABLE
440 .ascii "i"
441 #endif
442 #ifndef CONFIG_CPU_DCACHE_DISABLE
443 .ascii "d"
444 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
445 .ascii "(wt)"
446 #else
447 .ascii "(wb)"
448 #endif
449 #endif
450 .ascii "\0"
451 .size cpu_arm920_name, . - cpu_arm920_name
453 .align
455 .section ".proc.info.init", #alloc, #execinstr
457 .type __arm920_proc_info,#object
458 __arm920_proc_info:
459 .long 0x41009200
460 .long 0xff00fff0
461 .long PMD_TYPE_SECT | \
462 PMD_SECT_BUFFERABLE | \
463 PMD_SECT_CACHEABLE | \
464 PMD_BIT4 | \
465 PMD_SECT_AP_WRITE | \
466 PMD_SECT_AP_READ
467 b __arm920_setup
468 .long cpu_arch_name
469 .long cpu_elf_name
470 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
471 .long cpu_arm920_name
472 .long arm920_processor_functions
473 .long v4wbi_tlb_fns
474 .long v4wb_user_fns
475 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
476 .long arm920_cache_fns
477 #else
478 .long v4wt_cache_fns
479 #endif
480 .size __arm920_proc_info, . - __arm920_proc_info