1 /*
2 * arch/arm/include/asm/cacheflush.h
3 *
4 * Copyright (C) 1999-2002 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10 #ifndef _ASMARM_CACHEFLUSH_H
11 #define _ASMARM_CACHEFLUSH_H
12
13 #include <linux/mm.h>
14
15 #include <asm/glue-cache.h>
16 #include <asm/shmparam.h>
17 #include <asm/cachetype.h>
18 #include <asm/outercache.h>
19 #include <asm/rodata.h>
20
21 #define CACHE_COLOUR(vaddr) ((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT)
22
23 /*
24 * This flag is used to indicate that the page pointed to by a pte is clean
25 * and does not require cleaning before returning it to the user.
26 */
27 #define PG_dcache_clean PG_arch_1
28
29 /*
30 * MM Cache Management
31 * ===================
32 *
33 * The arch/arm/mm/cache-*.S and arch/arm/mm/proc-*.S files
34 * implement these methods.
35 *
36 * Start addresses are inclusive and end addresses are exclusive;
37 * start addresses should be rounded down, end addresses up.
38 *
39 * See Documentation/cachetlb.txt for more information.
40 * Please note that the implementation of these, and the required
41 * effects are cache-type (VIVT/VIPT/PIPT) specific.
42 *
43 * flush_icache_all()
44 *
45 * Unconditionally clean and invalidate the entire icache.
46 * Currently only needed for cache-v6.S and cache-v7.S, see
47 * __flush_icache_all for the generic implementation.
48 *
49 * flush_kern_all()
50 *
51 * Unconditionally clean and invalidate the entire cache.
52 *
53 * flush_kern_louis()
54 *
55 * Flush data cache levels up to the level of unification
56 * inner shareable and invalidate the I-cache.
57 * Only needed from v7 onwards, falls back to flush_cache_all()
58 * for all other processor versions.
59 *
60 * flush_user_all()
61 *
62 * Clean and invalidate all user space cache entries
63 * before a change of page tables.
64 *
65 * flush_user_range(start, end, flags)
66 *
67 * Clean and invalidate a range of cache entries in the
68 * specified address space before a change of page tables.
69 * - start - user start address (inclusive, page aligned)
70 * - end - user end address (exclusive, page aligned)
71 * - flags - vma->vm_flags field
72 *
73 * coherent_kern_range(start, end)
74 *
75 * Ensure coherency between the Icache and the Dcache in the
76 * region described by start, end. If you have non-snooping
77 * Harvard caches, you need to implement this function.
78 * - start - virtual start address
79 * - end - virtual end address
80 *
81 * coherent_user_range(start, end)
82 *
83 * Ensure coherency between the Icache and the Dcache in the
84 * region described by start, end. If you have non-snooping
85 * Harvard caches, you need to implement this function.
86 * - start - virtual start address
87 * - end - virtual end address
88 *
89 * flush_kern_dcache_area(kaddr, size)
90 *
91 * Ensure that the data held in page is written back.
92 * - kaddr - page address
93 * - size - region size
94 *
95 * DMA Cache Coherency
96 * ===================
97 *
98 * dma_flush_range(start, end)
99 *
100 * Clean and invalidate the specified virtual address range.
101 * - start - virtual start address
102 * - end - virtual end address
103 */
104
105 struct cpu_cache_fns {
106 void (*flush_icache_all)(void);
107 void (*flush_kern_all)(void);
108 void (*flush_kern_louis)(void);
109 void (*flush_user_all)(void);
110 void (*flush_user_range)(unsigned long, unsigned long, unsigned int);
111
112 void (*coherent_kern_range)(unsigned long, unsigned long);
113 int (*coherent_user_range)(unsigned long, unsigned long);
114 void (*flush_kern_dcache_area)(void *, size_t);
115
116 void (*dma_map_area)(const void *, size_t, int);
117 void (*dma_unmap_area)(const void *, size_t, int);
118
119 void (*dma_flush_range)(const void *, const void *);
120 };
121
122 /*
123 * Select the calling method
124 */
125 #ifdef MULTI_CACHE
126
127 extern struct cpu_cache_fns cpu_cache;
128
129 #define __cpuc_flush_icache_all cpu_cache.flush_icache_all
130 #define __cpuc_flush_kern_all cpu_cache.flush_kern_all
131 #define __cpuc_flush_kern_louis cpu_cache.flush_kern_louis
132 #define __cpuc_flush_user_all cpu_cache.flush_user_all
133 #define __cpuc_flush_user_range cpu_cache.flush_user_range
134 #define __cpuc_coherent_kern_range cpu_cache.coherent_kern_range
135 #define __cpuc_coherent_user_range cpu_cache.coherent_user_range
136 #define __cpuc_flush_dcache_area cpu_cache.flush_kern_dcache_area
137
138 /*
139 * These are private to the dma-mapping API. Do not use directly.
140 * Their sole purpose is to ensure that data held in the cache
141 * is visible to DMA, or data written by DMA to system memory is
142 * visible to the CPU.
143 */
144 #define dmac_map_area cpu_cache.dma_map_area
145 #define dmac_unmap_area cpu_cache.dma_unmap_area
146 #define dmac_flush_range cpu_cache.dma_flush_range
147
148 #else
149
150 extern void __cpuc_flush_icache_all(void);
151 extern void __cpuc_flush_kern_all(void);
152 extern void __cpuc_flush_kern_louis(void);
153 extern void __cpuc_flush_user_all(void);
154 extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int);
155 extern void __cpuc_coherent_kern_range(unsigned long, unsigned long);
156 extern int __cpuc_coherent_user_range(unsigned long, unsigned long);
157 extern void __cpuc_flush_dcache_area(void *, size_t);
158
159 /*
160 * These are private to the dma-mapping API. Do not use directly.
161 * Their sole purpose is to ensure that data held in the cache
162 * is visible to DMA, or data written by DMA to system memory is
163 * visible to the CPU.
164 */
165 extern void dmac_map_area(const void *, size_t, int);
166 extern void dmac_unmap_area(const void *, size_t, int);
167 extern void dmac_flush_range(const void *, const void *);
168
169 #endif
170
171 /*
172 * Copy user data from/to a page which is mapped into a different
173 * processes address space. Really, we want to allow our "user
174 * space" model to handle this.
175 */
176 extern void copy_to_user_page(struct vm_area_struct *, struct page *,
177 unsigned long, void *, const void *, unsigned long);
178 #define copy_from_user_page(vma, page, vaddr, dst, src, len) \
179 do { \
180 memcpy(dst, src, len); \
181 } while (0)
182
183 /*
184 * Convert calls to our calling convention.
185 */
186
187 /* Invalidate I-cache */
188 #define __flush_icache_all_generic() \
189 asm("mcr p15, 0, %0, c7, c5, 0" \
190 : : "r" (0));
191
192 /* Invalidate I-cache inner shareable */
193 #define __flush_icache_all_v7_smp() \
194 asm("mcr p15, 0, %0, c7, c1, 0" \
195 : : "r" (0));
196
197 /*
198 * Optimized __flush_icache_all for the common cases. Note that UP ARMv7
199 * will fall through to use __flush_icache_all_generic.
200 */
201 #if (defined(CONFIG_CPU_V7) && \
202 (defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K))) || \
203 defined(CONFIG_SMP_ON_UP)
204 #define __flush_icache_preferred __cpuc_flush_icache_all
205 #elif __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
206 #define __flush_icache_preferred __flush_icache_all_v7_smp
207 #elif __LINUX_ARM_ARCH__ == 6 && defined(CONFIG_ARM_ERRATA_411920)
208 #define __flush_icache_preferred __cpuc_flush_icache_all
209 #else
210 #define __flush_icache_preferred __flush_icache_all_generic
211 #endif
212
__flush_icache_all(void)213 static inline void __flush_icache_all(void)
214 {
215 __flush_icache_preferred();
216 }
217
218 /*
219 * Flush caches up to Level of Unification Inner Shareable
220 */
221 #define flush_cache_louis() __cpuc_flush_kern_louis()
222
223 #define flush_cache_all() __cpuc_flush_kern_all()
224
vivt_flush_cache_mm(struct mm_struct * mm)225 static inline void vivt_flush_cache_mm(struct mm_struct *mm)
226 {
227 if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
228 __cpuc_flush_user_all();
229 }
230
231 static inline void
vivt_flush_cache_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)232 vivt_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
233 {
234 struct mm_struct *mm = vma->vm_mm;
235
236 if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
237 __cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
238 vma->vm_flags);
239 }
240
241 static inline void
vivt_flush_cache_page(struct vm_area_struct * vma,unsigned long user_addr,unsigned long pfn)242 vivt_flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn)
243 {
244 struct mm_struct *mm = vma->vm_mm;
245
246 if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) {
247 unsigned long addr = user_addr & PAGE_MASK;
248 __cpuc_flush_user_range(addr, addr + PAGE_SIZE, vma->vm_flags);
249 }
250 }
251
252 #ifndef CONFIG_CPU_CACHE_VIPT
253 #define flush_cache_mm(mm) \
254 vivt_flush_cache_mm(mm)
255 #define flush_cache_range(vma,start,end) \
256 vivt_flush_cache_range(vma,start,end)
257 #define flush_cache_page(vma,addr,pfn) \
258 vivt_flush_cache_page(vma,addr,pfn)
259 #else
260 extern void flush_cache_mm(struct mm_struct *mm);
261 extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
262 extern void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn);
263 #endif
264
265 #define flush_cache_dup_mm(mm) flush_cache_mm(mm)
266
267 /*
268 * flush_cache_user_range is used when we want to ensure that the
269 * Harvard caches are synchronised for the user space address range.
270 * This is used for the ARM private sys_cacheflush system call.
271 */
272 #define flush_cache_user_range(start,end) \
273 __cpuc_coherent_user_range((start) & PAGE_MASK, PAGE_ALIGN(end))
274
275 /*
276 * Perform necessary cache operations to ensure that data previously
277 * stored within this range of addresses can be executed by the CPU.
278 */
279 #define flush_icache_range(s,e) __cpuc_coherent_kern_range(s,e)
280
281 /*
282 * Perform necessary cache operations to ensure that the TLB will
283 * see data written in the specified area.
284 */
285 #define clean_dcache_area(start,size) cpu_dcache_clean_area(start, size)
286
287 /*
288 * flush_dcache_page is used when the kernel has written to the page
289 * cache page at virtual address page->virtual.
290 *
291 * If this page isn't mapped (ie, page_mapping == NULL), or it might
292 * have userspace mappings, then we _must_ always clean + invalidate
293 * the dcache entries associated with the kernel mapping.
294 *
295 * Otherwise we can defer the operation, and clean the cache when we are
296 * about to change to user space. This is the same method as used on SPARC64.
297 * See update_mmu_cache for the user space part.
298 */
299 #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
300 extern void flush_dcache_page(struct page *);
301
flush_kernel_vmap_range(void * addr,int size)302 static inline void flush_kernel_vmap_range(void *addr, int size)
303 {
304 if ((cache_is_vivt() || cache_is_vipt_aliasing()))
305 __cpuc_flush_dcache_area(addr, (size_t)size);
306 }
invalidate_kernel_vmap_range(void * addr,int size)307 static inline void invalidate_kernel_vmap_range(void *addr, int size)
308 {
309 if ((cache_is_vivt() || cache_is_vipt_aliasing()))
310 __cpuc_flush_dcache_area(addr, (size_t)size);
311 }
312
313 #define ARCH_HAS_FLUSH_ANON_PAGE
flush_anon_page(struct vm_area_struct * vma,struct page * page,unsigned long vmaddr)314 static inline void flush_anon_page(struct vm_area_struct *vma,
315 struct page *page, unsigned long vmaddr)
316 {
317 extern void __flush_anon_page(struct vm_area_struct *vma,
318 struct page *, unsigned long);
319 if (PageAnon(page))
320 __flush_anon_page(vma, page, vmaddr);
321 }
322
323 #define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
324 extern void flush_kernel_dcache_page(struct page *);
325
326 #define flush_dcache_mmap_lock(mapping) \
327 spin_lock_irq(&(mapping)->tree_lock)
328 #define flush_dcache_mmap_unlock(mapping) \
329 spin_unlock_irq(&(mapping)->tree_lock)
330
331 #define flush_icache_user_range(vma,page,addr,len) \
332 flush_dcache_page(page)
333
334 /*
335 * We don't appear to need to do anything here. In fact, if we did, we'd
336 * duplicate cache flushing elsewhere performed by flush_dcache_page().
337 */
338 #define flush_icache_page(vma,page) do { } while (0)
339
340 /*
341 * flush_cache_vmap() is used when creating mappings (eg, via vmap,
342 * vmalloc, ioremap etc) in kernel space for pages. On non-VIPT
343 * caches, since the direct-mappings of these pages may contain cached
344 * data, we need to do a full cache flush to ensure that writebacks
345 * don't corrupt data placed into these pages via the new mappings.
346 */
flush_cache_vmap(unsigned long start,unsigned long end)347 static inline void flush_cache_vmap(unsigned long start, unsigned long end)
348 {
349 if (!cache_is_vipt_nonaliasing())
350 flush_cache_all();
351 else
352 /*
353 * set_pte_at() called from vmap_pte_range() does not
354 * have a DSB after cleaning the cache line.
355 */
356 dsb();
357 }
358
flush_cache_vunmap(unsigned long start,unsigned long end)359 static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
360 {
361 if (!cache_is_vipt_nonaliasing())
362 flush_cache_all();
363 }
364
365 /*
366 * Memory synchronization helpers for mixed cached vs non cached accesses.
367 *
368 * Some synchronization algorithms have to set states in memory with the
369 * cache enabled or disabled depending on the code path. It is crucial
370 * to always ensure proper cache maintenance to update main memory right
371 * away in that case.
372 *
373 * Any cached write must be followed by a cache clean operation.
374 * Any cached read must be preceded by a cache invalidate operation.
375 * Yet, in the read case, a cache flush i.e. atomic clean+invalidate
376 * operation is needed to avoid discarding possible concurrent writes to the
377 * accessed memory.
378 *
379 * Also, in order to prevent a cached writer from interfering with an
380 * adjacent non-cached writer, each state variable must be located to
381 * a separate cache line.
382 */
383
384 /*
385 * This needs to be >= the max cache writeback size of all
386 * supported platforms included in the current kernel configuration.
387 * This is used to align state variables to their own cache lines.
388 */
389 #define __CACHE_WRITEBACK_ORDER 6 /* guessed from existing platforms */
390 #define __CACHE_WRITEBACK_GRANULE (1 << __CACHE_WRITEBACK_ORDER)
391
392 /*
393 * There is no __cpuc_clean_dcache_area but we use it anyway for
394 * code intent clarity, and alias it to __cpuc_flush_dcache_area.
395 */
396 #define __cpuc_clean_dcache_area __cpuc_flush_dcache_area
397
398 /*
399 * Ensure preceding writes to *p by this CPU are visible to
400 * subsequent reads by other CPUs:
401 */
__sync_cache_range_w(volatile void * p,size_t size)402 static inline void __sync_cache_range_w(volatile void *p, size_t size)
403 {
404 char *_p = (char *)p;
405
406 __cpuc_clean_dcache_area(_p, size);
407 outer_clean_range(__pa(_p), __pa(_p + size));
408 }
409
410 /*
411 * Ensure preceding writes to *p by other CPUs are visible to
412 * subsequent reads by this CPU. We must be careful not to
413 * discard data simultaneously written by another CPU, hence the
414 * usage of flush rather than invalidate operations.
415 */
__sync_cache_range_r(volatile void * p,size_t size)416 static inline void __sync_cache_range_r(volatile void *p, size_t size)
417 {
418 char *_p = (char *)p;
419
420 #ifdef CONFIG_OUTER_CACHE
421 if (outer_cache.flush_range) {
422 /*
423 * Ensure dirty data migrated from other CPUs into our cache
424 * are cleaned out safely before the outer cache is cleaned:
425 */
426 __cpuc_clean_dcache_area(_p, size);
427
428 /* Clean and invalidate stale data for *p from outer ... */
429 outer_flush_range(__pa(_p), __pa(_p + size));
430 }
431 #endif
432
433 /* ... and inner cache: */
434 __cpuc_flush_dcache_area(_p, size);
435 }
436
437 #define sync_cache_w(ptr) __sync_cache_range_w(ptr, sizeof *(ptr))
438 #define sync_cache_r(ptr) __sync_cache_range_r(ptr, sizeof *(ptr))
439
440 #endif
441