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 ENTRY(cpu_arm922_reset)
92 mcr p15, 0, ip, c7, c7, 0 @ invalidate I,D caches
93 mcr p15, 0, ip, c7, c10, 4 @ drain WB
95 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
97 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
98 bic ip, ip, #0x000f @ ............wcam
99 bic ip, ip, #0x1100 @ ...i...s........
100 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
104 * cpu_arm922_do_idle()
107 ENTRY(cpu_arm922_do_idle)
108 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
112 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
117 * Unconditionally clean and invalidate the entire icache.
119 ENTRY(arm922_flush_icache_all)
121 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
123 ENDPROC(arm922_flush_icache_all)
126 * flush_user_cache_all()
128 * Clean and invalidate all cache entries in a particular
131 ENTRY(arm922_flush_user_cache_all)
135 * flush_kern_cache_all()
137 * Clean and invalidate the entire cache.
139 ENTRY(arm922_flush_kern_cache_all)
143 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 8 segments
144 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
145 2: mcr p15, 0, r3, c7, c14, 2 @ clean+invalidate D index
146 subs r3, r3, #1 << 26
147 bcs 2b @ entries 63 to 0
149 bcs 1b @ segments 7 to 0
151 mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache
152 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
156 * flush_user_cache_range(start, end, flags)
158 * Clean and invalidate a range of cache entries in the
159 * specified address range.
161 * - start - start address (inclusive)
162 * - end - end address (exclusive)
163 * - flags - vm_flags describing address space
165 ENTRY(arm922_flush_user_cache_range)
167 sub r3, r1, r0 @ calculate total size
168 cmp r3, #CACHE_DLIMIT
169 bhs __flush_whole_cache
171 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
173 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
174 add r0, r0, #CACHE_DLINESIZE
178 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
182 * coherent_kern_range(start, end)
184 * Ensure coherency between the Icache and the Dcache in the
185 * region described by start, end. If you have non-snooping
186 * Harvard caches, you need to implement this function.
188 * - start - virtual start address
189 * - end - virtual end address
191 ENTRY(arm922_coherent_kern_range)
195 * coherent_user_range(start, end)
197 * Ensure coherency between the Icache and the Dcache in the
198 * region described by start, end. If you have non-snooping
199 * Harvard caches, you need to implement this function.
201 * - start - virtual start address
202 * - end - virtual end address
204 ENTRY(arm922_coherent_user_range)
205 bic r0, r0, #CACHE_DLINESIZE - 1
206 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
207 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
208 add r0, r0, #CACHE_DLINESIZE
211 mcr p15, 0, r0, c7, c10, 4 @ drain WB
215 * flush_kern_dcache_area(void *addr, size_t size)
217 * Ensure no D cache aliasing occurs, either with itself or
220 * - addr - kernel address
221 * - size - region size
223 ENTRY(arm922_flush_kern_dcache_area)
225 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
226 add r0, r0, #CACHE_DLINESIZE
230 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
231 mcr p15, 0, r0, c7, c10, 4 @ drain WB
235 * dma_inv_range(start, end)
237 * Invalidate (discard) the specified virtual address range.
238 * May not write back any entries. If 'start' or 'end'
239 * are not cache line aligned, those lines must be written
242 * - start - virtual start address
243 * - end - virtual end address
247 arm922_dma_inv_range:
248 tst r0, #CACHE_DLINESIZE - 1
249 bic r0, r0, #CACHE_DLINESIZE - 1
250 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
251 tst r1, #CACHE_DLINESIZE - 1
252 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
253 1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
254 add r0, r0, #CACHE_DLINESIZE
257 mcr p15, 0, r0, c7, c10, 4 @ drain WB
261 * dma_clean_range(start, end)
263 * Clean the specified virtual address range.
265 * - start - virtual start address
266 * - end - virtual end address
270 arm922_dma_clean_range:
271 bic r0, r0, #CACHE_DLINESIZE - 1
272 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
273 add r0, r0, #CACHE_DLINESIZE
276 mcr p15, 0, r0, c7, c10, 4 @ drain WB
280 * dma_flush_range(start, end)
282 * Clean and invalidate the specified virtual address range.
284 * - start - virtual start address
285 * - end - virtual end address
287 ENTRY(arm922_dma_flush_range)
288 bic r0, r0, #CACHE_DLINESIZE - 1
289 1: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
290 add r0, r0, #CACHE_DLINESIZE
293 mcr p15, 0, r0, c7, c10, 4 @ drain WB
297 * dma_map_area(start, size, dir)
298 * - start - kernel virtual start address
299 * - size - size of region
300 * - dir - DMA direction
302 ENTRY(arm922_dma_map_area)
304 cmp r2, #DMA_TO_DEVICE
305 beq arm922_dma_clean_range
306 bcs arm922_dma_inv_range
307 b arm922_dma_flush_range
308 ENDPROC(arm922_dma_map_area)
311 * dma_unmap_area(start, size, dir)
312 * - start - kernel virtual start address
313 * - size - size of region
314 * - dir - DMA direction
316 ENTRY(arm922_dma_unmap_area)
318 ENDPROC(arm922_dma_unmap_area)
320 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
321 define_cache_functions arm922
325 ENTRY(cpu_arm922_dcache_clean_area)
326 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
327 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
328 add r0, r0, #CACHE_DLINESIZE
329 subs r1, r1, #CACHE_DLINESIZE
334 /* =============================== PageTable ============================== */
337 * cpu_arm922_switch_mm(pgd)
339 * Set the translation base pointer to be as described by pgd.
341 * pgd: new page tables
344 ENTRY(cpu_arm922_switch_mm)
347 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
348 mcr p15, 0, ip, c7, c6, 0 @ invalidate D cache
350 @ && 'Clean & Invalidate whole DCache'
351 @ && Re-written to use Index Ops.
352 @ && Uses registers r1, r3 and ip
354 mov r1, #(CACHE_DSEGMENTS - 1) << 5 @ 4 segments
355 1: orr r3, r1, #(CACHE_DENTRIES - 1) << 26 @ 64 entries
356 2: mcr p15, 0, r3, c7, c14, 2 @ clean & invalidate D index
357 subs r3, r3, #1 << 26
358 bcs 2b @ entries 63 to 0
360 bcs 1b @ segments 7 to 0
362 mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache
363 mcr p15, 0, ip, c7, c10, 4 @ drain WB
364 mcr p15, 0, r0, c2, c0, 0 @ load page table pointer
365 mcr p15, 0, ip, c8, c7, 0 @ invalidate I & D TLBs
370 * cpu_arm922_set_pte_ext(ptep, pte, ext)
372 * Set a PTE and flush it out
375 ENTRY(cpu_arm922_set_pte_ext)
379 mcr p15, 0, r0, c7, c10, 1 @ clean D entry
380 mcr p15, 0, r0, c7, c10, 4 @ drain WB
381 #endif /* CONFIG_MMU */
386 .type __arm922_setup, #function
389 mcr p15, 0, r0, c7, c7 @ invalidate I,D caches on v4
390 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4
392 mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4
396 mrc p15, 0, r0, c1, c0 @ get control register v4
400 .size __arm922_setup, . - __arm922_setup
404 * .RVI ZFRS BLDP WCAM
405 * ..11 0001 ..11 0101
408 .type arm922_crval, #object
410 crval clear=0x00003f3f, mmuset=0x00003135, ucset=0x00001130
413 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
414 define_processor_functions arm922, dabort=v4t_early_abort, pabort=legacy_pabort
418 string cpu_arch_name, "armv4t"
419 string cpu_elf_name, "v4"
420 string cpu_arm922_name, "ARM922T"
424 .section ".proc.info.init", #alloc, #execinstr
426 .type __arm922_proc_info,#object
430 .long PMD_TYPE_SECT | \
431 PMD_SECT_BUFFERABLE | \
432 PMD_SECT_CACHEABLE | \
434 PMD_SECT_AP_WRITE | \
436 .long PMD_TYPE_SECT | \
438 PMD_SECT_AP_WRITE | \
443 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
444 .long cpu_arm922_name
445 .long arm922_processor_functions
448 #ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
449 .long arm922_cache_fns
453 .size __arm922_proc_info, . - __arm922_proc_info