1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *  arch/arm/include/asm/cacheflush.h
4 *
5 *  Copyright (C) 1999-2002 Russell King
6 */
7#ifndef _ASMARM_CACHEFLUSH_H
8#define _ASMARM_CACHEFLUSH_H
9
10#include <linux/mm.h>
11
12#include <asm/glue-cache.h>
13#include <asm/shmparam.h>
14#include <asm/cachetype.h>
15#include <asm/outercache.h>
16
17#define CACHE_COLOUR(vaddr)	((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT)
18
19/*
20 * This flag is used to indicate that the page pointed to by a pte is clean
21 * and does not require cleaning before returning it to the user.
22 */
23#define PG_dcache_clean PG_arch_1
24
25/*
26 *	MM Cache Management
27 *	===================
28 *
29 *	The arch/arm/mm/cache-*.S and arch/arm/mm/proc-*.S files
30 *	implement these methods.
31 *
32 *	Start addresses are inclusive and end addresses are exclusive;
33 *	start addresses should be rounded down, end addresses up.
34 *
35 *	See Documentation/core-api/cachetlb.rst for more information.
36 *	Please note that the implementation of these, and the required
37 *	effects are cache-type (VIVT/VIPT/PIPT) specific.
38 *
39 *	flush_icache_all()
40 *
41 *		Unconditionally clean and invalidate the entire icache.
42 *		Currently only needed for cache-v6.S and cache-v7.S, see
43 *		__flush_icache_all for the generic implementation.
44 *
45 *	flush_kern_all()
46 *
47 *		Unconditionally clean and invalidate the entire cache.
48 *
49 *     flush_kern_louis()
50 *
51 *             Flush data cache levels up to the level of unification
52 *             inner shareable and invalidate the I-cache.
53 *             Only needed from v7 onwards, falls back to flush_cache_all()
54 *             for all other processor versions.
55 *
56 *	flush_user_all()
57 *
58 *		Clean and invalidate all user space cache entries
59 *		before a change of page tables.
60 *
61 *	flush_user_range(start, end, flags)
62 *
63 *		Clean and invalidate a range of cache entries in the
64 *		specified address space before a change of page tables.
65 *		- start - user start address (inclusive, page aligned)
66 *		- end   - user end address   (exclusive, page aligned)
67 *		- flags - vma->vm_flags field
68 *
69 *	coherent_kern_range(start, end)
70 *
71 *		Ensure coherency between the Icache and the Dcache in the
72 *		region described by start, end.  If you have non-snooping
73 *		Harvard caches, you need to implement this function.
74 *		- start  - virtual start address
75 *		- end    - virtual end address
76 *
77 *	coherent_user_range(start, end)
78 *
79 *		Ensure coherency between the Icache and the Dcache in the
80 *		region described by start, end.  If you have non-snooping
81 *		Harvard caches, you need to implement this function.
82 *		- start  - virtual start address
83 *		- end    - virtual end address
84 *
85 *	flush_kern_dcache_area(kaddr, size)
86 *
87 *		Ensure that the data held in page is written back.
88 *		- kaddr  - page address
89 *		- size   - region size
90 *
91 *	DMA Cache Coherency
92 *	===================
93 *
94 *	dma_flush_range(start, end)
95 *
96 *		Clean and invalidate the specified virtual address range.
97 *		- start  - virtual start address
98 *		- end    - virtual end address
99 */
100
101struct cpu_cache_fns {
102	void (*flush_icache_all)(void);
103	void (*flush_kern_all)(void);
104	void (*flush_kern_louis)(void);
105	void (*flush_user_all)(void);
106	void (*flush_user_range)(unsigned long, unsigned long, unsigned int);
107
108	void (*coherent_kern_range)(unsigned long, unsigned long);
109	int  (*coherent_user_range)(unsigned long, unsigned long);
110	void (*flush_kern_dcache_area)(void *, size_t);
111
112	void (*dma_map_area)(const void *, size_t, int);
113	void (*dma_unmap_area)(const void *, size_t, int);
114
115	void (*dma_flush_range)(const void *, const void *);
116} __no_randomize_layout;
117
118/*
119 * Select the calling method
120 */
121#ifdef MULTI_CACHE
122
123extern struct cpu_cache_fns cpu_cache;
124
125#define __cpuc_flush_icache_all		cpu_cache.flush_icache_all
126#define __cpuc_flush_kern_all		cpu_cache.flush_kern_all
127#define __cpuc_flush_kern_louis		cpu_cache.flush_kern_louis
128#define __cpuc_flush_user_all		cpu_cache.flush_user_all
129#define __cpuc_flush_user_range		cpu_cache.flush_user_range
130#define __cpuc_coherent_kern_range	cpu_cache.coherent_kern_range
131#define __cpuc_coherent_user_range	cpu_cache.coherent_user_range
132#define __cpuc_flush_dcache_area	cpu_cache.flush_kern_dcache_area
133
134/*
135 * These are private to the dma-mapping API.  Do not use directly.
136 * Their sole purpose is to ensure that data held in the cache
137 * is visible to DMA, or data written by DMA to system memory is
138 * visible to the CPU.
139 */
140#define dmac_flush_range		cpu_cache.dma_flush_range
141
142#else
143
144extern void __cpuc_flush_icache_all(void);
145extern void __cpuc_flush_kern_all(void);
146extern void __cpuc_flush_kern_louis(void);
147extern void __cpuc_flush_user_all(void);
148extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int);
149extern void __cpuc_coherent_kern_range(unsigned long, unsigned long);
150extern int  __cpuc_coherent_user_range(unsigned long, unsigned long);
151extern void __cpuc_flush_dcache_area(void *, size_t);
152
153/*
154 * These are private to the dma-mapping API.  Do not use directly.
155 * Their sole purpose is to ensure that data held in the cache
156 * is visible to DMA, or data written by DMA to system memory is
157 * visible to the CPU.
158 */
159extern void dmac_flush_range(const void *, const void *);
160
161#endif
162
163/*
164 * Copy user data from/to a page which is mapped into a different
165 * processes address space.  Really, we want to allow our "user
166 * space" model to handle this.
167 */
168extern void copy_to_user_page(struct vm_area_struct *, struct page *,
169	unsigned long, void *, const void *, unsigned long);
170#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
171	do {							\
172		memcpy(dst, src, len);				\
173	} while (0)
174
175/*
176 * Convert calls to our calling convention.
177 */
178
179/* Invalidate I-cache */
180#define __flush_icache_all_generic()					\
181	asm("mcr	p15, 0, %0, c7, c5, 0"				\
182	    : : "r" (0));
183
184/* Invalidate I-cache inner shareable */
185#define __flush_icache_all_v7_smp()					\
186	asm("mcr	p15, 0, %0, c7, c1, 0"				\
187	    : : "r" (0));
188
189/*
190 * Optimized __flush_icache_all for the common cases. Note that UP ARMv7
191 * will fall through to use __flush_icache_all_generic.
192 */
193#if (defined(CONFIG_CPU_V7) && \
194     (defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K))) || \
195	defined(CONFIG_SMP_ON_UP)
196#define __flush_icache_preferred	__cpuc_flush_icache_all
197#elif __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
198#define __flush_icache_preferred	__flush_icache_all_v7_smp
199#elif __LINUX_ARM_ARCH__ == 6 && defined(CONFIG_ARM_ERRATA_411920)
200#define __flush_icache_preferred	__cpuc_flush_icache_all
201#else
202#define __flush_icache_preferred	__flush_icache_all_generic
203#endif
204
205static inline void __flush_icache_all(void)
206{
207	__flush_icache_preferred();
208	dsb(ishst);
209}
210
211/*
212 * Flush caches up to Level of Unification Inner Shareable
213 */
214#define flush_cache_louis()		__cpuc_flush_kern_louis()
215
216#define flush_cache_all()		__cpuc_flush_kern_all()
217
218static inline void vivt_flush_cache_mm(struct mm_struct *mm)
219{
220	if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
221		__cpuc_flush_user_all();
222}
223
224static inline void
225vivt_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
226{
227	struct mm_struct *mm = vma->vm_mm;
228
229	if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
230		__cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
231					vma->vm_flags);
232}
233
234static inline void vivt_flush_cache_pages(struct vm_area_struct *vma,
235		unsigned long user_addr, unsigned long pfn, unsigned int nr)
236{
237	struct mm_struct *mm = vma->vm_mm;
238
239	if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) {
240		unsigned long addr = user_addr & PAGE_MASK;
241		__cpuc_flush_user_range(addr, addr + nr * PAGE_SIZE,
242				vma->vm_flags);
243	}
244}
245
246#ifndef CONFIG_CPU_CACHE_VIPT
247#define flush_cache_mm(mm) \
248		vivt_flush_cache_mm(mm)
249#define flush_cache_range(vma,start,end) \
250		vivt_flush_cache_range(vma,start,end)
251#define flush_cache_pages(vma, addr, pfn, nr) \
252		vivt_flush_cache_pages(vma, addr, pfn, nr)
253#else
254void flush_cache_mm(struct mm_struct *mm);
255void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
256void flush_cache_pages(struct vm_area_struct *vma, unsigned long user_addr,
257		unsigned long pfn, unsigned int nr);
258#endif
259
260#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
261#define flush_cache_page(vma, addr, pfn) flush_cache_pages(vma, addr, pfn, 1)
262
263/*
264 * flush_icache_user_range is used when we want to ensure that the
265 * Harvard caches are synchronised for the user space address range.
266 * This is used for the ARM private sys_cacheflush system call.
267 */
268#define flush_icache_user_range(s,e)	__cpuc_coherent_user_range(s,e)
269
270/*
271 * Perform necessary cache operations to ensure that data previously
272 * stored within this range of addresses can be executed by the CPU.
273 */
274#define flush_icache_range(s,e)		__cpuc_coherent_kern_range(s,e)
275
276/*
277 * Perform necessary cache operations to ensure that the TLB will
278 * see data written in the specified area.
279 */
280#define clean_dcache_area(start,size)	cpu_dcache_clean_area(start, size)
281
282/*
283 * flush_dcache_page is used when the kernel has written to the page
284 * cache page at virtual address page->virtual.
285 *
286 * If this page isn't mapped (ie, page_mapping == NULL), or it might
287 * have userspace mappings, then we _must_ always clean + invalidate
288 * the dcache entries associated with the kernel mapping.
289 *
290 * Otherwise we can defer the operation, and clean the cache when we are
291 * about to change to user space.  This is the same method as used on SPARC64.
292 * See update_mmu_cache for the user space part.
293 */
294#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
295void flush_dcache_page(struct page *);
296void flush_dcache_folio(struct folio *folio);
297#define flush_dcache_folio flush_dcache_folio
298
299#define ARCH_IMPLEMENTS_FLUSH_KERNEL_VMAP_RANGE 1
300static inline void flush_kernel_vmap_range(void *addr, int size)
301{
302	if ((cache_is_vivt() || cache_is_vipt_aliasing()))
303	  __cpuc_flush_dcache_area(addr, (size_t)size);
304}
305static inline void invalidate_kernel_vmap_range(void *addr, int size)
306{
307	if ((cache_is_vivt() || cache_is_vipt_aliasing()))
308	  __cpuc_flush_dcache_area(addr, (size_t)size);
309}
310
311#define ARCH_HAS_FLUSH_ANON_PAGE
312static inline void flush_anon_page(struct vm_area_struct *vma,
313			 struct page *page, unsigned long vmaddr)
314{
315	extern void __flush_anon_page(struct vm_area_struct *vma,
316				struct page *, unsigned long);
317	if (PageAnon(page))
318		__flush_anon_page(vma, page, vmaddr);
319}
320
321#define flush_dcache_mmap_lock(mapping)		xa_lock_irq(&mapping->i_pages)
322#define flush_dcache_mmap_unlock(mapping)	xa_unlock_irq(&mapping->i_pages)
323
324/*
325 * flush_cache_vmap() is used when creating mappings (eg, via vmap,
326 * vmalloc, ioremap etc) in kernel space for pages.  On non-VIPT
327 * caches, since the direct-mappings of these pages may contain cached
328 * data, we need to do a full cache flush to ensure that writebacks
329 * don't corrupt data placed into these pages via the new mappings.
330 */
331static inline void flush_cache_vmap(unsigned long start, unsigned long end)
332{
333	if (!cache_is_vipt_nonaliasing())
334		flush_cache_all();
335	else
336		/*
337		 * set_pte_at() called from vmap_pte_range() does not
338		 * have a DSB after cleaning the cache line.
339		 */
340		dsb(ishst);
341}
342
343#define flush_cache_vmap_early(start, end)	do { } while (0)
344
345static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
346{
347	if (!cache_is_vipt_nonaliasing())
348		flush_cache_all();
349}
350
351/*
352 * Memory synchronization helpers for mixed cached vs non cached accesses.
353 *
354 * Some synchronization algorithms have to set states in memory with the
355 * cache enabled or disabled depending on the code path.  It is crucial
356 * to always ensure proper cache maintenance to update main memory right
357 * away in that case.
358 *
359 * Any cached write must be followed by a cache clean operation.
360 * Any cached read must be preceded by a cache invalidate operation.
361 * Yet, in the read case, a cache flush i.e. atomic clean+invalidate
362 * operation is needed to avoid discarding possible concurrent writes to the
363 * accessed memory.
364 *
365 * Also, in order to prevent a cached writer from interfering with an
366 * adjacent non-cached writer, each state variable must be located to
367 * a separate cache line.
368 */
369
370/*
371 * This needs to be >= the max cache writeback size of all
372 * supported platforms included in the current kernel configuration.
373 * This is used to align state variables to their own cache lines.
374 */
375#define __CACHE_WRITEBACK_ORDER 6  /* guessed from existing platforms */
376#define __CACHE_WRITEBACK_GRANULE (1 << __CACHE_WRITEBACK_ORDER)
377
378/*
379 * There is no __cpuc_clean_dcache_area but we use it anyway for
380 * code intent clarity, and alias it to __cpuc_flush_dcache_area.
381 */
382#define __cpuc_clean_dcache_area __cpuc_flush_dcache_area
383
384/*
385 * Ensure preceding writes to *p by this CPU are visible to
386 * subsequent reads by other CPUs:
387 */
388static inline void __sync_cache_range_w(volatile void *p, size_t size)
389{
390	char *_p = (char *)p;
391
392	__cpuc_clean_dcache_area(_p, size);
393	outer_clean_range(__pa(_p), __pa(_p + size));
394}
395
396/*
397 * Ensure preceding writes to *p by other CPUs are visible to
398 * subsequent reads by this CPU.  We must be careful not to
399 * discard data simultaneously written by another CPU, hence the
400 * usage of flush rather than invalidate operations.
401 */
402static inline void __sync_cache_range_r(volatile void *p, size_t size)
403{
404	char *_p = (char *)p;
405
406#ifdef CONFIG_OUTER_CACHE
407	if (outer_cache.flush_range) {
408		/*
409		 * Ensure dirty data migrated from other CPUs into our cache
410		 * are cleaned out safely before the outer cache is cleaned:
411		 */
412		__cpuc_clean_dcache_area(_p, size);
413
414		/* Clean and invalidate stale data for *p from outer ... */
415		outer_flush_range(__pa(_p), __pa(_p + size));
416	}
417#endif
418
419	/* ... and inner cache: */
420	__cpuc_flush_dcache_area(_p, size);
421}
422
423#define sync_cache_w(ptr) __sync_cache_range_w(ptr, sizeof *(ptr))
424#define sync_cache_r(ptr) __sync_cache_range_r(ptr, sizeof *(ptr))
425
426/*
427 * Disabling cache access for one CPU in an ARMv7 SMP system is tricky.
428 * To do so we must:
429 *
430 * - Clear the SCTLR.C bit to prevent further cache allocations
431 * - Flush the desired level of cache
432 * - Clear the ACTLR "SMP" bit to disable local coherency
433 *
434 * ... and so without any intervening memory access in between those steps,
435 * not even to the stack.
436 *
437 * WARNING -- After this has been called:
438 *
439 * - No ldrex/strex (and similar) instructions must be used.
440 * - The CPU is obviously no longer coherent with the other CPUs.
441 * - This is unlikely to work as expected if Linux is running non-secure.
442 *
443 * Note:
444 *
445 * - This is known to apply to several ARMv7 processor implementations,
446 *   however some exceptions may exist.  Caveat emptor.
447 *
448 * - The clobber list is dictated by the call to v7_flush_dcache_*.
449 */
450#define v7_exit_coherency_flush(level) \
451	asm volatile( \
452	".arch	armv7-a \n\t" \
453	"mrc	p15, 0, r0, c1, c0, 0	@ get SCTLR \n\t" \
454	"bic	r0, r0, #"__stringify(CR_C)" \n\t" \
455	"mcr	p15, 0, r0, c1, c0, 0	@ set SCTLR \n\t" \
456	"isb	\n\t" \
457	"bl	v7_flush_dcache_"__stringify(level)" \n\t" \
458	"mrc	p15, 0, r0, c1, c0, 1	@ get ACTLR \n\t" \
459	"bic	r0, r0, #(1 << 6)	@ disable local coherency \n\t" \
460	"mcr	p15, 0, r0, c1, c0, 1	@ set ACTLR \n\t" \
461	"isb	\n\t" \
462	"dsb" \
463	: : : "r0","r1","r2","r3","r4","r5","r6", \
464	      "r9","r10","ip","lr","memory" )
465
466void flush_uprobe_xol_access(struct page *page, unsigned long uaddr,
467			     void *kaddr, unsigned long len);
468
469
470#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
471void check_cpu_icache_size(int cpuid);
472#else
473static inline void check_cpu_icache_size(int cpuid) { }
474#endif
475
476#endif
477