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 ENTRY(cpu_arm920_reset)
90 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
91 mcr p15, 0, ip, c7, c10, 4 @ drain WB
93 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
95 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
96 bic ip, ip, #0x000f @ ............wcam
97 bic ip, ip, #0x1100 @ ...i...s........
98 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
102 * cpu_arm920_do_idle()
105 ENTRY(cpu_arm920_do_idle)
106 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
110 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
115 * Unconditionally clean and invalidate the entire icache.
117 ENTRY(arm920_flush_icache_all)
119 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
121 ENDPROC(arm920_flush_icache_all)
124 * flush_user_cache_all()
126 * Invalidate all cache entries in a particular address
129 ENTRY(arm920_flush_user_cache_all)
133 * flush_kern_cache_all()
135 * Clean and invalidate the entire cache.
137 ENTRY(arm920_flush_kern_cache_all)
141 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
142 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
143 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
144 subs r3, r3, #1 << 26
145 bcs 2b @ entries 63 to 0
147 bcs 1b @ segments 7 to 0
149 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
150 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
154 * flush_user_cache_range(start, end, flags)
156 * Invalidate a range of cache entries in the specified
159 * - start - start address (inclusive)
160 * - end - end address (exclusive)
161 * - flags - vm_flags for address space
163 ENTRY(arm920_flush_user_cache_range)
165 sub r3, r1, r0 @ calculate total size
166 cmp r3, #CACHE_DLIMIT
167 bhs __flush_whole_cache
169 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
171 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
172 add r0, r0, #CACHE_DLINESIZE
176 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
180 * coherent_kern_range(start, end)
182 * Ensure coherency between the Icache and the Dcache in the
183 * region described by start, end. If you have non-snooping
184 * Harvard caches, you need to implement this function.
186 * - start - virtual start address
187 * - end - virtual end address
189 ENTRY(arm920_coherent_kern_range)
193 * coherent_user_range(start, end)
195 * Ensure coherency between the Icache and the Dcache in the
196 * region described by start, end. If you have non-snooping
197 * Harvard caches, you need to implement this function.
199 * - start - virtual start address
200 * - end - virtual end address
202 ENTRY(arm920_coherent_user_range)
203 bic r0, r0, #CACHE_DLINESIZE - 1
204 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
205 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
206 add r0, r0, #CACHE_DLINESIZE
209 mcr p15, 0, r0, c7, c10, 4 @ drain WB
213 * flush_kern_dcache_area(void *addr, size_t size)
215 * Ensure no D cache aliasing occurs, either with itself or
218 * - addr - kernel address
219 * - size - region size
221 ENTRY(arm920_flush_kern_dcache_area)
223 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
224 add r0, r0, #CACHE_DLINESIZE
228 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
229 mcr p15, 0, r0, c7, c10, 4 @ drain WB
233 * dma_inv_range(start, end)
235 * Invalidate (discard) the specified virtual address range.
236 * May not write back any entries. If 'start' or 'end'
237 * are not cache line aligned, those lines must be written
240 * - start - virtual start address
241 * - end - virtual end address
245 arm920_dma_inv_range:
246 tst r0, #CACHE_DLINESIZE - 1
247 bic r0, r0, #CACHE_DLINESIZE - 1
248 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
249 tst r1, #CACHE_DLINESIZE - 1
250 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
251 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
252 add r0, r0, #CACHE_DLINESIZE
255 mcr p15, 0, r0, c7, c10, 4 @ drain WB
259 * dma_clean_range(start, end)
261 * Clean the specified virtual address range.
263 * - start - virtual start address
264 * - end - virtual end address
268 arm920_dma_clean_range:
269 bic r0, r0, #CACHE_DLINESIZE - 1
270 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
271 add r0, r0, #CACHE_DLINESIZE
274 mcr p15, 0, r0, c7, c10, 4 @ drain WB
278 * dma_flush_range(start, end)
280 * Clean and invalidate the specified virtual address range.
282 * - start - virtual start address
283 * - end - virtual end address
285 ENTRY(arm920_dma_flush_range)
286 bic r0, r0, #CACHE_DLINESIZE - 1
287 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
288 add r0, r0, #CACHE_DLINESIZE
291 mcr p15, 0, r0, c7, c10, 4 @ drain WB
295 * dma_map_area(start, size, dir)
296 * - start - kernel virtual start address
297 * - size - size of region
298 * - dir - DMA direction
300 ENTRY(arm920_dma_map_area)
302 cmp r2, #DMA_TO_DEVICE
303 beq arm920_dma_clean_range
304 bcs arm920_dma_inv_range
305 b arm920_dma_flush_range
306 ENDPROC(arm920_dma_map_area)
309 * dma_unmap_area(start, size, dir)
310 * - start - kernel virtual start address
311 * - size - size of region
312 * - dir - DMA direction
314 ENTRY(arm920_dma_unmap_area)
316 ENDPROC(arm920_dma_unmap_area)
318 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
319 define_cache_functions arm920
323 ENTRY(cpu_arm920_dcache_clean_area)
324 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
325 add r0, r0, #CACHE_DLINESIZE
326 subs r1, r1, #CACHE_DLINESIZE
330 /* =============================== PageTable ============================== */
333 * cpu_arm920_switch_mm(pgd)
335 * Set the translation base pointer to be as described by pgd.
337 * pgd: new page tables
340 ENTRY(cpu_arm920_switch_mm)
343 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
344 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
346 @ && 'Clean & Invalidate whole DCache'
347 @ && Re-written to use Index Ops.
348 @ && Uses registers r1, r3 and ip
350 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
351 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
352 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
353 subs r3, r3, #1 << 26
354 bcs 2b @ entries 63 to 0
356 bcs 1b @ segments 7 to 0
358 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
359 mcr p15, 0, ip, c7, c10, 4 @ drain WB
360 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
361 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
366 * cpu_arm920_set_pte(ptep, pte, ext)
368 * Set a PTE and flush it out
371 ENTRY(cpu_arm920_set_pte_ext)
375 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
376 mcr p15, 0, r0, c7, c10, 4 @ drain WB
380 /* Suspend/resume support: taken from arch/arm/plat-s3c24xx/sleep.S */
381 .globl cpu_arm920_suspend_size
382 .equ cpu_arm920_suspend_size, 4 * 3
383 #ifdef CONFIG_PM_SLEEP
384 ENTRY(cpu_arm920_do_suspend)
385 stmfd sp!, {r4 - r7, lr}
386 mrc p15, 0, r4, c13, c0, 0 @ PID
387 mrc p15, 0, r5, c3, c0, 0 @ Domain ID
388 mrc p15, 0, r6, c2, c0, 0 @ TTB address
389 mrc p15, 0, r7, c1, c0, 0 @ Control register
391 ldmfd sp!, {r4 - r7, pc}
392 ENDPROC(cpu_arm920_do_suspend)
394 ENTRY(cpu_arm920_do_resume)
396 mcr p15, 0, ip, c8, c7, 0 @ invalidate I+D TLBs
397 mcr p15, 0, ip, c7, c7, 0 @ invalidate I+D caches
399 mcr p15, 0, r4, c13, c0, 0 @ PID
400 mcr p15, 0, r5, c3, c0, 0 @ Domain ID
401 mcr p15, 0, r6, c2, c0, 0 @ TTB address
402 mov r0, r7 @ control register
403 mov r2, r6, lsr #14 @ get TTB0 base
405 ldr r3, =PMD_TYPE_SECT | PMD_SECT_BUFFERABLE | \
406 PMD_SECT_CACHEABLE | PMD_BIT4 | PMD_SECT_AP_WRITE
408 ENDPROC(cpu_arm920_do_resume)
413 .type __arm920_setup, #function
416 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
417 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
419 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
423 mrc p15, 0, r0, c1, c0 @ get control register v4
427 .size __arm920_setup, . - __arm920_setup
431 * .RVI ZFRS BLDP WCAM
432 * ..11 0001 ..11 0101
435 .type arm920_crval, #object
437 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
440 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
441 define_processor_functions arm920, dabort=v4t_early_abort, pabort=legacy_pabort, suspend=1
445 string cpu_arch_name, "armv4t"
446 string cpu_elf_name, "v4"
447 string cpu_arm920_name, "ARM920T"
451 .section ".proc.info.init", #alloc, #execinstr
453 .type __arm920_proc_info,#object
457 .long PMD_TYPE_SECT | \
458 PMD_SECT_BUFFERABLE | \
459 PMD_SECT_CACHEABLE | \
461 PMD_SECT_AP_WRITE | \
463 .long PMD_TYPE_SECT | \
465 PMD_SECT_AP_WRITE | \
470 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
471 .long cpu_arm920_name
472 .long arm920_processor_functions
475 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
476 .long arm920_cache_fns
480 .size __arm920_proc_info, . - __arm920_proc_info