2 * linux/arch/arm/mm/proc-arm920.S: MMU functions for ARM920
4 * Copyright (C) 1999,2000 ARM Limited
5 * Copyright (C) 2000 Deep Blue Solutions Ltd.
6 * hacked for non-paged-MM by Hyok S. Choi, 2003.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * These are the low level assembler for performing cache and TLB
24 * functions on the arm920.
26 * CONFIG_CPU_ARM920_CPU_IDLE -> nohlt
28 #include <linux/linkage.h>
29 #include <linux/init.h>
30 #include <asm/assembler.h>
31 #include <asm/hwcap.h>
32 #include <asm/pgtable-hwdef.h>
33 #include <asm/pgtable.h>
35 #include <asm/ptrace.h>
36 #include "proc-macros.S"
39 * The size of one data cache line.
41 #define CACHE_DLINESIZE 32
44 * The number of data cache segments.
46 #define CACHE_DSEGMENTS 8
49 * The number of lines in a cache segment.
51 #define CACHE_DENTRIES 64
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 maintenance instructions.
58 #define CACHE_DLIMIT 65536
63 * cpu_arm920_proc_init()
65 ENTRY(cpu_arm920_proc_init)
69 * cpu_arm920_proc_fin()
71 ENTRY(cpu_arm920_proc_fin)
72 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
73 bic r0, r0, #0x1000 @ ...i............
74 bic r0, r0, #0x000e @ ............wca.
75 mcr p15, 0, r0, c1, c0, 0 @ disable caches
79 * cpu_arm920_reset(loc)
81 * Perform a soft reset of the system. Put the CPU into the
82 * same state as it would be if it had been reset, and branch
83 * to what would be the reset vector.
85 * loc: location to jump to for soft reset
88 .pushsection .idmap.text, "ax"
89 ENTRY(cpu_arm920_reset)
91 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
92 mcr p15, 0, ip, c7, c10, 4 @ drain WB
94 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
96 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
97 bic ip, ip, #0x000f @ ............wcam
98 bic ip, ip, #0x1100 @ ...i...s........
99 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
101 ENDPROC(cpu_arm920_reset)
105 * cpu_arm920_do_idle()
108 ENTRY(cpu_arm920_do_idle)
109 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
113 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
118 * Unconditionally clean and invalidate the entire icache.
120 ENTRY(arm920_flush_icache_all)
122 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
124 ENDPROC(arm920_flush_icache_all)
127 * flush_user_cache_all()
129 * Invalidate all cache entries in a particular address
132 ENTRY(arm920_flush_user_cache_all)
136 * flush_kern_cache_all()
138 * Clean and invalidate the entire cache.
140 ENTRY(arm920_flush_kern_cache_all)
144 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
145 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
146 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
147 subs r3, r3, #1 << 26
148 bcs 2b @ entries 63 to 0
150 bcs 1b @ segments 7 to 0
152 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
153 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
157 * flush_user_cache_range(start, end, flags)
159 * Invalidate a range of cache entries in the specified
162 * - start - start address (inclusive)
163 * - end - end address (exclusive)
164 * - flags - vm_flags for address space
166 ENTRY(arm920_flush_user_cache_range)
168 sub r3, r1, r0 @ calculate total size
169 cmp r3, #CACHE_DLIMIT
170 bhs __flush_whole_cache
172 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
174 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
175 add r0, r0, #CACHE_DLINESIZE
179 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
183 * coherent_kern_range(start, end)
185 * Ensure coherency between the Icache and the Dcache in the
186 * region described by start, end. If you have non-snooping
187 * Harvard caches, you need to implement this function.
189 * - start - virtual start address
190 * - end - virtual end address
192 ENTRY(arm920_coherent_kern_range)
196 * coherent_user_range(start, end)
198 * Ensure coherency between the Icache and the Dcache in the
199 * region described by start, end. If you have non-snooping
200 * Harvard caches, you need to implement this function.
202 * - start - virtual start address
203 * - end - virtual end address
205 ENTRY(arm920_coherent_user_range)
206 bic r0, r0, #CACHE_DLINESIZE - 1
207 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
208 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
209 add r0, r0, #CACHE_DLINESIZE
212 mcr p15, 0, r0, c7, c10, 4 @ drain WB
217 * flush_kern_dcache_area(void *addr, size_t size)
219 * Ensure no D cache aliasing occurs, either with itself or
222 * - addr - kernel address
223 * - size - region size
225 ENTRY(arm920_flush_kern_dcache_area)
227 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
228 add r0, r0, #CACHE_DLINESIZE
232 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
233 mcr p15, 0, r0, c7, c10, 4 @ drain WB
237 * dma_inv_range(start, end)
239 * Invalidate (discard) the specified virtual address range.
240 * May not write back any entries. If 'start' or 'end'
241 * are not cache line aligned, those lines must be written
244 * - start - virtual start address
245 * - end - virtual end address
249 arm920_dma_inv_range:
250 tst r0, #CACHE_DLINESIZE - 1
251 bic r0, r0, #CACHE_DLINESIZE - 1
252 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
253 tst r1, #CACHE_DLINESIZE - 1
254 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
255 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
256 add r0, r0, #CACHE_DLINESIZE
259 mcr p15, 0, r0, c7, c10, 4 @ drain WB
263 * dma_clean_range(start, end)
265 * Clean the specified virtual address range.
267 * - start - virtual start address
268 * - end - virtual end address
272 arm920_dma_clean_range:
273 bic r0, r0, #CACHE_DLINESIZE - 1
274 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
275 add r0, r0, #CACHE_DLINESIZE
278 mcr p15, 0, r0, c7, c10, 4 @ drain WB
282 * dma_flush_range(start, end)
284 * Clean and invalidate the specified virtual address range.
286 * - start - virtual start address
287 * - end - virtual end address
289 ENTRY(arm920_dma_flush_range)
290 bic r0, r0, #CACHE_DLINESIZE - 1
291 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
292 add r0, r0, #CACHE_DLINESIZE
295 mcr p15, 0, r0, c7, c10, 4 @ drain WB
299 * dma_map_area(start, size, dir)
300 * - start - kernel virtual start address
301 * - size - size of region
302 * - dir - DMA direction
304 ENTRY(arm920_dma_map_area)
306 cmp r2, #DMA_TO_DEVICE
307 beq arm920_dma_clean_range
308 bcs arm920_dma_inv_range
309 b arm920_dma_flush_range
310 ENDPROC(arm920_dma_map_area)
313 * dma_unmap_area(start, size, dir)
314 * - start - kernel virtual start address
315 * - size - size of region
316 * - dir - DMA direction
318 ENTRY(arm920_dma_unmap_area)
320 ENDPROC(arm920_dma_unmap_area)
322 .globl arm920_flush_kern_cache_louis
323 .equ arm920_flush_kern_cache_louis, arm920_flush_kern_cache_all
325 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
326 define_cache_functions arm920
330 ENTRY(cpu_arm920_dcache_clean_area)
331 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
332 add r0, r0, #CACHE_DLINESIZE
333 subs r1, r1, #CACHE_DLINESIZE
337 /* =============================== PageTable ============================== */
340 * cpu_arm920_switch_mm(pgd)
342 * Set the translation base pointer to be as described by pgd.
344 * pgd: new page tables
347 ENTRY(cpu_arm920_switch_mm)
350 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
351 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
353 @ && 'Clean & Invalidate whole DCache'
354 @ && Re-written to use Index Ops.
355 @ && Uses registers r1, r3 and ip
357 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
358 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
359 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
360 subs r3, r3, #1 << 26
361 bcs 2b @ entries 63 to 0
363 bcs 1b @ segments 7 to 0
365 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
366 mcr p15, 0, ip, c7, c10, 4 @ drain WB
367 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
368 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
373 * cpu_arm920_set_pte(ptep, pte, ext)
375 * Set a PTE and flush it out
378 ENTRY(cpu_arm920_set_pte_ext)
382 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
383 mcr p15, 0, r0, c7, c10, 4 @ drain WB
387 /* Suspend/resume support: taken from arch/arm/plat-s3c24xx/sleep.S */
388 .globl cpu_arm920_suspend_size
389 .equ cpu_arm920_suspend_size, 4 * 3
390 #ifdef CONFIG_ARM_CPU_SUSPEND
391 ENTRY(cpu_arm920_do_suspend)
392 stmfd sp!, {r4 - r6, lr}
393 mrc p15, 0, r4, c13, c0, 0 @ PID
394 mrc p15, 0, r5, c3, c0, 0 @ Domain ID
395 mrc p15, 0, r6, c1, c0, 0 @ Control register
397 ldmfd sp!, {r4 - r6, pc}
398 ENDPROC(cpu_arm920_do_suspend)
400 ENTRY(cpu_arm920_do_resume)
402 mcr p15, 0, ip, c8, c7, 0 @ invalidate I+D TLBs
403 mcr p15, 0, ip, c7, c7, 0 @ invalidate I+D caches
405 mcr p15, 0, r4, c13, c0, 0 @ PID
406 mcr p15, 0, r5, c3, c0, 0 @ Domain ID
407 mcr p15, 0, r1, c2, c0, 0 @ TTB address
408 mov r0, r6 @ control register
410 ENDPROC(cpu_arm920_do_resume)
415 .type __arm920_setup, #function
418 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
419 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
421 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
425 mrc p15, 0, r0, c1, c0 @ get control register v4
429 .size __arm920_setup, . - __arm920_setup
433 * .RVI ZFRS BLDP WCAM
434 * ..11 0001 ..11 0101
437 .type arm920_crval, #object
439 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
442 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
443 define_processor_functions arm920, dabort=v4t_early_abort, pabort=legacy_pabort, suspend=1
447 string cpu_arch_name, "armv4t"
448 string cpu_elf_name, "v4"
449 string cpu_arm920_name, "ARM920T"
453 .section ".proc.info.init", #alloc, #execinstr
455 .type __arm920_proc_info,#object
459 .long PMD_TYPE_SECT | \
460 PMD_SECT_BUFFERABLE | \
461 PMD_SECT_CACHEABLE | \
463 PMD_SECT_AP_WRITE | \
465 .long PMD_TYPE_SECT | \
467 PMD_SECT_AP_WRITE | \
472 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
473 .long cpu_arm920_name
474 .long arm920_processor_functions
477 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
478 .long arm920_cache_fns
482 .size __arm920_proc_info, . - __arm920_proc_info