2 * linux/arch/arm/mm/proc-arm922.S: MMU functions for ARM922
4 * Copyright (C) 1999,2000 ARM Limited
5 * Copyright (C) 2000 Deep Blue Solutions Ltd.
6 * Copyright (C) 2001 Altera Corporation
7 * hacked for non-paged-MM by Hyok S. Choi, 2003.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 * These are the low level assembler for performing cache and TLB
25 * functions on the arm922.
27 * CONFIG_CPU_ARM922_CPU_IDLE -> nohlt
29 #include <linux/linkage.h>
30 #include <linux/init.h>
31 #include <asm/assembler.h>
32 #include <asm/hwcap.h>
33 #include <asm/pgtable-hwdef.h>
34 #include <asm/pgtable.h>
36 #include <asm/ptrace.h>
37 #include "proc-macros.S"
40 * The size of one data cache line.
42 #define CACHE_DLINESIZE 32
45 * The number of data cache segments.
47 #define CACHE_DSEGMENTS 4
50 * The number of lines in a cache segment.
52 #define CACHE_DENTRIES 64
55 * This is the size at which it becomes more efficient to
56 * clean the whole cache, rather than using the individual
57 * cache line maintenance instructions. (I think this should
60 #define CACHE_DLIMIT 8192
65 * cpu_arm922_proc_init()
67 ENTRY(cpu_arm922_proc_init)
71 * cpu_arm922_proc_fin()
73 ENTRY(cpu_arm922_proc_fin)
74 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
75 bic r0, r0, #0x1000 @ ...i............
76 bic r0, r0, #0x000e @ ............wca.
77 mcr p15, 0, r0, c1, c0, 0 @ disable caches
81 * cpu_arm922_reset(loc)
83 * Perform a soft reset of the system. Put the CPU into the
84 * same state as it would be if it had been reset, and branch
85 * to what would be the reset vector.
87 * loc: location to jump to for soft reset
90 .pushsection .idmap.text, "ax"
91 ENTRY(cpu_arm922_reset)
93 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
94 mcr p15, 0, ip, c7, c10, 4 @ drain WB
96 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
98 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
99 bic ip, ip, #0x000f @ ............wcam
100 bic ip, ip, #0x1100 @ ...i...s........
101 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
103 ENDPROC(cpu_arm922_reset)
107 * cpu_arm922_do_idle()
110 ENTRY(cpu_arm922_do_idle)
111 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
115 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
120 * Unconditionally clean and invalidate the entire icache.
122 ENTRY(arm922_flush_icache_all)
124 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
126 ENDPROC(arm922_flush_icache_all)
129 * flush_user_cache_all()
131 * Clean and invalidate all cache entries in a particular
134 ENTRY(arm922_flush_user_cache_all)
138 * flush_kern_cache_all()
140 * Clean and invalidate the entire cache.
142 ENTRY(arm922_flush_kern_cache_all)
146 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
147 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
148 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
149 subs r3, r3, #1 << 26
150 bcs 2b @ entries 63 to 0
152 bcs 1b @ segments 7 to 0
154 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
155 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
159 * flush_user_cache_range(start, end, flags)
161 * Clean and invalidate a range of cache entries in the
162 * specified address range.
164 * - start - start address (inclusive)
165 * - end - end address (exclusive)
166 * - flags - vm_flags describing address space
168 ENTRY(arm922_flush_user_cache_range)
170 sub r3, r1, r0 @ calculate total size
171 cmp r3, #CACHE_DLIMIT
172 bhs __flush_whole_cache
174 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
176 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
177 add r0, r0, #CACHE_DLINESIZE
181 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
185 * coherent_kern_range(start, end)
187 * Ensure coherency between the Icache and the Dcache in the
188 * region described by start, end. If you have non-snooping
189 * Harvard caches, you need to implement this function.
191 * - start - virtual start address
192 * - end - virtual end address
194 ENTRY(arm922_coherent_kern_range)
198 * coherent_user_range(start, end)
200 * Ensure coherency between the Icache and the Dcache in the
201 * region described by start, end. If you have non-snooping
202 * Harvard caches, you need to implement this function.
204 * - start - virtual start address
205 * - end - virtual end address
207 ENTRY(arm922_coherent_user_range)
208 bic r0, r0, #CACHE_DLINESIZE - 1
209 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
210 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
211 add r0, r0, #CACHE_DLINESIZE
214 mcr p15, 0, r0, c7, c10, 4 @ drain WB
218 * flush_kern_dcache_area(void *addr, size_t size)
220 * Ensure no D cache aliasing occurs, either with itself or
223 * - addr - kernel address
224 * - size - region size
226 ENTRY(arm922_flush_kern_dcache_area)
228 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
229 add r0, r0, #CACHE_DLINESIZE
233 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
234 mcr p15, 0, r0, c7, c10, 4 @ drain WB
238 * dma_inv_range(start, end)
240 * Invalidate (discard) the specified virtual address range.
241 * May not write back any entries. If 'start' or 'end'
242 * are not cache line aligned, those lines must be written
245 * - start - virtual start address
246 * - end - virtual end address
250 arm922_dma_inv_range:
251 tst r0, #CACHE_DLINESIZE - 1
252 bic r0, r0, #CACHE_DLINESIZE - 1
253 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
254 tst r1, #CACHE_DLINESIZE - 1
255 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
256 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
257 add r0, r0, #CACHE_DLINESIZE
260 mcr p15, 0, r0, c7, c10, 4 @ drain WB
264 * dma_clean_range(start, end)
266 * Clean the specified virtual address range.
268 * - start - virtual start address
269 * - end - virtual end address
273 arm922_dma_clean_range:
274 bic r0, r0, #CACHE_DLINESIZE - 1
275 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
276 add r0, r0, #CACHE_DLINESIZE
279 mcr p15, 0, r0, c7, c10, 4 @ drain WB
283 * dma_flush_range(start, end)
285 * Clean and invalidate the specified virtual address range.
287 * - start - virtual start address
288 * - end - virtual end address
290 ENTRY(arm922_dma_flush_range)
291 bic r0, r0, #CACHE_DLINESIZE - 1
292 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
293 add r0, r0, #CACHE_DLINESIZE
296 mcr p15, 0, r0, c7, c10, 4 @ drain WB
300 * dma_map_area(start, size, dir)
301 * - start - kernel virtual start address
302 * - size - size of region
303 * - dir - DMA direction
305 ENTRY(arm922_dma_map_area)
307 cmp r2, #DMA_TO_DEVICE
308 beq arm922_dma_clean_range
309 bcs arm922_dma_inv_range
310 b arm922_dma_flush_range
311 ENDPROC(arm922_dma_map_area)
314 * dma_unmap_area(start, size, dir)
315 * - start - kernel virtual start address
316 * - size - size of region
317 * - dir - DMA direction
319 ENTRY(arm922_dma_unmap_area)
321 ENDPROC(arm922_dma_unmap_area)
323 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
324 define_cache_functions arm922
328 ENTRY(cpu_arm922_dcache_clean_area)
329 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
330 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
331 add r0, r0, #CACHE_DLINESIZE
332 subs r1, r1, #CACHE_DLINESIZE
337 /* =============================== PageTable ============================== */
340 * cpu_arm922_switch_mm(pgd)
342 * Set the translation base pointer to be as described by pgd.
344 * pgd: new page tables
347 ENTRY(cpu_arm922_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 @ 4 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_arm922_set_pte_ext(ptep, pte, ext)
375 * Set a PTE and flush it out
378 ENTRY(cpu_arm922_set_pte_ext)
382 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
383 mcr p15, 0, r0, c7, c10, 4 @ drain WB
384 #endif /* CONFIG_MMU */
389 .type __arm922_setup, #function
392 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
393 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
395 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
399 mrc p15, 0, r0, c1, c0 @ get control register v4
403 .size __arm922_setup, . - __arm922_setup
407 * .RVI ZFRS BLDP WCAM
408 * ..11 0001 ..11 0101
411 .type arm922_crval, #object
413 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
416 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
417 define_processor_functions arm922, dabort=v4t_early_abort, pabort=legacy_pabort
421 string cpu_arch_name, "armv4t"
422 string cpu_elf_name, "v4"
423 string cpu_arm922_name, "ARM922T"
427 .section ".proc.info.init", #alloc, #execinstr
429 .type __arm922_proc_info,#object
433 .long PMD_TYPE_SECT | \
434 PMD_SECT_BUFFERABLE | \
435 PMD_SECT_CACHEABLE | \
437 PMD_SECT_AP_WRITE | \
439 .long PMD_TYPE_SECT | \
441 PMD_SECT_AP_WRITE | \
446 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
447 .long cpu_arm922_name
448 .long arm922_processor_functions
451 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
452 .long arm922_cache_fns
456 .size __arm922_proc_info, . - __arm922_proc_info