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
219 * flush_kern_dcache_area(void *addr, size_t size)
221 * Ensure no D cache aliasing occurs, either with itself or
224 * - addr - kernel address
225 * - size - region size
227 ENTRY(arm922_flush_kern_dcache_area)
229 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
230 add r0, r0, #CACHE_DLINESIZE
234 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
235 mcr p15, 0, r0, c7, c10, 4 @ drain WB
239 * dma_inv_range(start, end)
241 * Invalidate (discard) the specified virtual address range.
242 * May not write back any entries. If 'start' or 'end'
243 * are not cache line aligned, those lines must be written
246 * - start - virtual start address
247 * - end - virtual end address
251 arm922_dma_inv_range:
252 tst r0, #CACHE_DLINESIZE - 1
253 bic r0, r0, #CACHE_DLINESIZE - 1
254 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
255 tst r1, #CACHE_DLINESIZE - 1
256 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
257 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
258 add r0, r0, #CACHE_DLINESIZE
261 mcr p15, 0, r0, c7, c10, 4 @ drain WB
265 * dma_clean_range(start, end)
267 * Clean the specified virtual address range.
269 * - start - virtual start address
270 * - end - virtual end address
274 arm922_dma_clean_range:
275 bic r0, r0, #CACHE_DLINESIZE - 1
276 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
277 add r0, r0, #CACHE_DLINESIZE
280 mcr p15, 0, r0, c7, c10, 4 @ drain WB
284 * dma_flush_range(start, end)
286 * Clean and invalidate the specified virtual address range.
288 * - start - virtual start address
289 * - end - virtual end address
291 ENTRY(arm922_dma_flush_range)
292 bic r0, r0, #CACHE_DLINESIZE - 1
293 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
294 add r0, r0, #CACHE_DLINESIZE
297 mcr p15, 0, r0, c7, c10, 4 @ drain WB
301 * dma_map_area(start, size, dir)
302 * - start - kernel virtual start address
303 * - size - size of region
304 * - dir - DMA direction
306 ENTRY(arm922_dma_map_area)
308 cmp r2, #DMA_TO_DEVICE
309 beq arm922_dma_clean_range
310 bcs arm922_dma_inv_range
311 b arm922_dma_flush_range
312 ENDPROC(arm922_dma_map_area)
315 * dma_unmap_area(start, size, dir)
316 * - start - kernel virtual start address
317 * - size - size of region
318 * - dir - DMA direction
320 ENTRY(arm922_dma_unmap_area)
322 ENDPROC(arm922_dma_unmap_area)
324 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
325 define_cache_functions arm922
329 ENTRY(cpu_arm922_dcache_clean_area)
330 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
331 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
332 add r0, r0, #CACHE_DLINESIZE
333 subs r1, r1, #CACHE_DLINESIZE
338 /* =============================== PageTable ============================== */
341 * cpu_arm922_switch_mm(pgd)
343 * Set the translation base pointer to be as described by pgd.
345 * pgd: new page tables
348 ENTRY(cpu_arm922_switch_mm)
351 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
352 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
354 @ && 'Clean & Invalidate whole DCache'
355 @ && Re-written to use Index Ops.
356 @ && Uses registers r1, r3 and ip
358 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 4 segments
359 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
360 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
361 subs r3, r3, #1 << 26
362 bcs 2b @ entries 63 to 0
364 bcs 1b @ segments 7 to 0
366 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
367 mcr p15, 0, ip, c7, c10, 4 @ drain WB
368 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
369 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
374 * cpu_arm922_set_pte_ext(ptep, pte, ext)
376 * Set a PTE and flush it out
379 ENTRY(cpu_arm922_set_pte_ext)
383 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
384 mcr p15, 0, r0, c7, c10, 4 @ drain WB
385 #endif /* CONFIG_MMU */
390 .type __arm922_setup, #function
393 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
394 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
396 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
400 mrc p15, 0, r0, c1, c0 @ get control register v4
404 .size __arm922_setup, . - __arm922_setup
408 * .RVI ZFRS BLDP WCAM
409 * ..11 0001 ..11 0101
412 .type arm922_crval, #object
414 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
417 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
418 define_processor_functions arm922, dabort=v4t_early_abort, pabort=legacy_pabort
422 string cpu_arch_name, "armv4t"
423 string cpu_elf_name, "v4"
424 string cpu_arm922_name, "ARM922T"
428 .section ".proc.info.init", #alloc, #execinstr
430 .type __arm922_proc_info,#object
434 .long PMD_TYPE_SECT | \
435 PMD_SECT_BUFFERABLE | \
436 PMD_SECT_CACHEABLE | \
438 PMD_SECT_AP_WRITE | \
440 .long PMD_TYPE_SECT | \
442 PMD_SECT_AP_WRITE | \
447 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
448 .long cpu_arm922_name
449 .long arm922_processor_functions
452 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
453 .long arm922_cache_fns
457 .size __arm922_proc_info, . - __arm922_proc_info