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Diffstat (limited to 'arch/arm/include/asm/cacheflush.h')
| -rw-r--r-- | arch/arm/include/asm/cacheflush.h | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h new file mode 100644 index 000000000..2e24e765e --- /dev/null +++ b/arch/arm/include/asm/cacheflush.h @@ -0,0 +1,483 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * arch/arm/include/asm/cacheflush.h + * + * Copyright (C) 1999-2002 Russell King + */ +#ifndef _ASMARM_CACHEFLUSH_H +#define _ASMARM_CACHEFLUSH_H + +#include <linux/mm.h> + +#include <asm/glue-cache.h> +#include <asm/shmparam.h> +#include <asm/cachetype.h> +#include <asm/outercache.h> + +#define CACHE_COLOUR(vaddr) ((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT) + +/* + * This flag is used to indicate that the page pointed to by a pte is clean + * and does not require cleaning before returning it to the user. + */ +#define PG_dcache_clean PG_arch_1 + +/* + * MM Cache Management + * =================== + * + * The arch/arm/mm/cache-*.S and arch/arm/mm/proc-*.S files + * implement these methods. + * + * Start addresses are inclusive and end addresses are exclusive; + * start addresses should be rounded down, end addresses up. + * + * See Documentation/core-api/cachetlb.rst for more information. + * Please note that the implementation of these, and the required + * effects are cache-type (VIVT/VIPT/PIPT) specific. + * + * flush_icache_all() + * + * Unconditionally clean and invalidate the entire icache. + * Currently only needed for cache-v6.S and cache-v7.S, see + * __flush_icache_all for the generic implementation. + * + * flush_kern_all() + * + * Unconditionally clean and invalidate the entire cache. + * + * flush_kern_louis() + * + * Flush data cache levels up to the level of unification + * inner shareable and invalidate the I-cache. + * Only needed from v7 onwards, falls back to flush_cache_all() + * for all other processor versions. + * + * flush_user_all() + * + * Clean and invalidate all user space cache entries + * before a change of page tables. + * + * flush_user_range(start, end, flags) + * + * Clean and invalidate a range of cache entries in the + * specified address space before a change of page tables. + * - start - user start address (inclusive, page aligned) + * - end - user end address (exclusive, page aligned) + * - flags - vma->vm_flags field + * + * coherent_kern_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start, end. If you have non-snooping + * Harvard caches, you need to implement this function. + * - start - virtual start address + * - end - virtual end address + * + * coherent_user_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start, end. If you have non-snooping + * Harvard caches, you need to implement this function. + * - start - virtual start address + * - end - virtual end address + * + * flush_kern_dcache_area(kaddr, size) + * + * Ensure that the data held in page is written back. + * - kaddr - page address + * - size - region size + * + * DMA Cache Coherency + * =================== + * + * dma_flush_range(start, end) + * + * Clean and invalidate the specified virtual address range. + * - start - virtual start address + * - end - virtual end address + */ + +struct cpu_cache_fns { + void (*flush_icache_all)(void); + void (*flush_kern_all)(void); + void (*flush_kern_louis)(void); + void (*flush_user_all)(void); + void (*flush_user_range)(unsigned long, unsigned long, unsigned int); + + void (*coherent_kern_range)(unsigned long, unsigned long); + int (*coherent_user_range)(unsigned long, unsigned long); + void (*flush_kern_dcache_area)(void *, size_t); + + void (*dma_map_area)(const void *, size_t, int); + void (*dma_unmap_area)(const void *, size_t, int); + + void (*dma_flush_range)(const void *, const void *); +} __no_randomize_layout; + +/* + * Select the calling method + */ +#ifdef MULTI_CACHE + +extern struct cpu_cache_fns cpu_cache; + +#define __cpuc_flush_icache_all cpu_cache.flush_icache_all +#define __cpuc_flush_kern_all cpu_cache.flush_kern_all +#define __cpuc_flush_kern_louis cpu_cache.flush_kern_louis +#define __cpuc_flush_user_all cpu_cache.flush_user_all +#define __cpuc_flush_user_range cpu_cache.flush_user_range +#define __cpuc_coherent_kern_range cpu_cache.coherent_kern_range +#define __cpuc_coherent_user_range cpu_cache.coherent_user_range +#define __cpuc_flush_dcache_area cpu_cache.flush_kern_dcache_area + +/* + * These are private to the dma-mapping API. Do not use directly. + * Their sole purpose is to ensure that data held in the cache + * is visible to DMA, or data written by DMA to system memory is + * visible to the CPU. + */ +#define dmac_flush_range cpu_cache.dma_flush_range + +#else + +extern void __cpuc_flush_icache_all(void); +extern void __cpuc_flush_kern_all(void); +extern void __cpuc_flush_kern_louis(void); +extern void __cpuc_flush_user_all(void); +extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int); +extern void __cpuc_coherent_kern_range(unsigned long, unsigned long); +extern int __cpuc_coherent_user_range(unsigned long, unsigned long); +extern void __cpuc_flush_dcache_area(void *, size_t); + +/* + * These are private to the dma-mapping API. Do not use directly. + * Their sole purpose is to ensure that data held in the cache + * is visible to DMA, or data written by DMA to system memory is + * visible to the CPU. + */ +extern void dmac_flush_range(const void *, const void *); + +#endif + +/* + * Copy user data from/to a page which is mapped into a different + * processes address space. Really, we want to allow our "user + * space" model to handle this. + */ +extern void copy_to_user_page(struct vm_area_struct *, struct page *, + unsigned long, void *, const void *, unsigned long); +#define copy_from_user_page(vma, page, vaddr, dst, src, len) \ + do { \ + memcpy(dst, src, len); \ + } while (0) + +/* + * Convert calls to our calling convention. + */ + +/* Invalidate I-cache */ +#define __flush_icache_all_generic() \ + asm("mcr p15, 0, %0, c7, c5, 0" \ + : : "r" (0)); + +/* Invalidate I-cache inner shareable */ +#define __flush_icache_all_v7_smp() \ + asm("mcr p15, 0, %0, c7, c1, 0" \ + : : "r" (0)); + +/* + * Optimized __flush_icache_all for the common cases. Note that UP ARMv7 + * will fall through to use __flush_icache_all_generic. + */ +#if (defined(CONFIG_CPU_V7) && \ + (defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K))) || \ + defined(CONFIG_SMP_ON_UP) +#define __flush_icache_preferred __cpuc_flush_icache_all +#elif __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP) +#define __flush_icache_preferred __flush_icache_all_v7_smp +#elif __LINUX_ARM_ARCH__ == 6 && defined(CONFIG_ARM_ERRATA_411920) +#define __flush_icache_preferred __cpuc_flush_icache_all +#else +#define __flush_icache_preferred __flush_icache_all_generic +#endif + +static inline void __flush_icache_all(void) +{ + __flush_icache_preferred(); + dsb(ishst); +} + +/* + * Flush caches up to Level of Unification Inner Shareable + */ +#define flush_cache_louis() __cpuc_flush_kern_louis() + +#define flush_cache_all() __cpuc_flush_kern_all() + +static inline void vivt_flush_cache_mm(struct mm_struct *mm) +{ + if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) + __cpuc_flush_user_all(); +} + +static inline void +vivt_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) +{ + struct mm_struct *mm = vma->vm_mm; + + if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) + __cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end), + vma->vm_flags); +} + +static inline void +vivt_flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn) +{ + struct mm_struct *mm = vma->vm_mm; + + if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm))) { + unsigned long addr = user_addr & PAGE_MASK; + __cpuc_flush_user_range(addr, addr + PAGE_SIZE, vma->vm_flags); + } +} + +#ifndef CONFIG_CPU_CACHE_VIPT +#define flush_cache_mm(mm) \ + vivt_flush_cache_mm(mm) +#define flush_cache_range(vma,start,end) \ + vivt_flush_cache_range(vma,start,end) +#define flush_cache_page(vma,addr,pfn) \ + vivt_flush_cache_page(vma,addr,pfn) +#else +extern void flush_cache_mm(struct mm_struct *mm); +extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); +extern void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn); +#endif + +#define flush_cache_dup_mm(mm) flush_cache_mm(mm) + +/* + * flush_icache_user_range is used when we want to ensure that the + * Harvard caches are synchronised for the user space address range. + * This is used for the ARM private sys_cacheflush system call. + */ +#define flush_icache_user_range(s,e) __cpuc_coherent_user_range(s,e) + +/* + * Perform necessary cache operations to ensure that data previously + * stored within this range of addresses can be executed by the CPU. + */ +#define flush_icache_range(s,e) __cpuc_coherent_kern_range(s,e) + +/* + * Perform necessary cache operations to ensure that the TLB will + * see data written in the specified area. + */ +#define clean_dcache_area(start,size) cpu_dcache_clean_area(start, size) + +/* + * flush_dcache_page is used when the kernel has written to the page + * cache page at virtual address page->virtual. + * + * If this page isn't mapped (ie, page_mapping == NULL), or it might + * have userspace mappings, then we _must_ always clean + invalidate + * the dcache entries associated with the kernel mapping. + * + * Otherwise we can defer the operation, and clean the cache when we are + * about to change to user space. This is the same method as used on SPARC64. + * See update_mmu_cache for the user space part. + */ +#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 +extern void flush_dcache_page(struct page *); + +static inline void flush_kernel_vmap_range(void *addr, int size) +{ + if ((cache_is_vivt() || cache_is_vipt_aliasing())) + __cpuc_flush_dcache_area(addr, (size_t)size); +} +static inline void invalidate_kernel_vmap_range(void *addr, int size) +{ + if ((cache_is_vivt() || cache_is_vipt_aliasing())) + __cpuc_flush_dcache_area(addr, (size_t)size); +} + +#define ARCH_HAS_FLUSH_ANON_PAGE +static inline void flush_anon_page(struct vm_area_struct *vma, + struct page *page, unsigned long vmaddr) +{ + extern void __flush_anon_page(struct vm_area_struct *vma, + struct page *, unsigned long); + if (PageAnon(page)) + __flush_anon_page(vma, page, vmaddr); +} + +#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE +extern void flush_kernel_dcache_page(struct page *); + +#define flush_dcache_mmap_lock(mapping) xa_lock_irq(&mapping->i_pages) +#define flush_dcache_mmap_unlock(mapping) xa_unlock_irq(&mapping->i_pages) + +/* + * We don't appear to need to do anything here. In fact, if we did, we'd + * duplicate cache flushing elsewhere performed by flush_dcache_page(). + */ +#define flush_icache_page(vma,page) do { } while (0) + +/* + * flush_cache_vmap() is used when creating mappings (eg, via vmap, + * vmalloc, ioremap etc) in kernel space for pages. On non-VIPT + * caches, since the direct-mappings of these pages may contain cached + * data, we need to do a full cache flush to ensure that writebacks + * don't corrupt data placed into these pages via the new mappings. + */ +static inline void flush_cache_vmap(unsigned long start, unsigned long end) +{ + if (!cache_is_vipt_nonaliasing()) + flush_cache_all(); + else + /* + * set_pte_at() called from vmap_pte_range() does not + * have a DSB after cleaning the cache line. + */ + dsb(ishst); +} + +static inline void flush_cache_vunmap(unsigned long start, unsigned long end) +{ + if (!cache_is_vipt_nonaliasing()) + flush_cache_all(); +} + +/* + * Memory synchronization helpers for mixed cached vs non cached accesses. + * + * Some synchronization algorithms have to set states in memory with the + * cache enabled or disabled depending on the code path. It is crucial + * to always ensure proper cache maintenance to update main memory right + * away in that case. + * + * Any cached write must be followed by a cache clean operation. + * Any cached read must be preceded by a cache invalidate operation. + * Yet, in the read case, a cache flush i.e. atomic clean+invalidate + * operation is needed to avoid discarding possible concurrent writes to the + * accessed memory. + * + * Also, in order to prevent a cached writer from interfering with an + * adjacent non-cached writer, each state variable must be located to + * a separate cache line. + */ + +/* + * This needs to be >= the max cache writeback size of all + * supported platforms included in the current kernel configuration. + * This is used to align state variables to their own cache lines. + */ +#define __CACHE_WRITEBACK_ORDER 6 /* guessed from existing platforms */ +#define __CACHE_WRITEBACK_GRANULE (1 << __CACHE_WRITEBACK_ORDER) + +/* + * There is no __cpuc_clean_dcache_area but we use it anyway for + * code intent clarity, and alias it to __cpuc_flush_dcache_area. + */ +#define __cpuc_clean_dcache_area __cpuc_flush_dcache_area + +/* + * Ensure preceding writes to *p by this CPU are visible to + * subsequent reads by other CPUs: + */ +static inline void __sync_cache_range_w(volatile void *p, size_t size) +{ + char *_p = (char *)p; + + __cpuc_clean_dcache_area(_p, size); + outer_clean_range(__pa(_p), __pa(_p + size)); +} + +/* + * Ensure preceding writes to *p by other CPUs are visible to + * subsequent reads by this CPU. We must be careful not to + * discard data simultaneously written by another CPU, hence the + * usage of flush rather than invalidate operations. + */ +static inline void __sync_cache_range_r(volatile void *p, size_t size) +{ + char *_p = (char *)p; + +#ifdef CONFIG_OUTER_CACHE + if (outer_cache.flush_range) { + /* + * Ensure dirty data migrated from other CPUs into our cache + * are cleaned out safely before the outer cache is cleaned: + */ + __cpuc_clean_dcache_area(_p, size); + + /* Clean and invalidate stale data for *p from outer ... */ + outer_flush_range(__pa(_p), __pa(_p + size)); + } +#endif + + /* ... and inner cache: */ + __cpuc_flush_dcache_area(_p, size); +} + +#define sync_cache_w(ptr) __sync_cache_range_w(ptr, sizeof *(ptr)) +#define sync_cache_r(ptr) __sync_cache_range_r(ptr, sizeof *(ptr)) + +/* + * Disabling cache access for one CPU in an ARMv7 SMP system is tricky. + * To do so we must: + * + * - Clear the SCTLR.C bit to prevent further cache allocations + * - Flush the desired level of cache + * - Clear the ACTLR "SMP" bit to disable local coherency + * + * ... and so without any intervening memory access in between those steps, + * not even to the stack. + * + * WARNING -- After this has been called: + * + * - No ldrex/strex (and similar) instructions must be used. + * - The CPU is obviously no longer coherent with the other CPUs. + * - This is unlikely to work as expected if Linux is running non-secure. + * + * Note: + * + * - This is known to apply to several ARMv7 processor implementations, + * however some exceptions may exist. Caveat emptor. + * + * - The clobber list is dictated by the call to v7_flush_dcache_*. + * fp is preserved to the stack explicitly prior disabling the cache + * since adding it to the clobber list is incompatible with having + * CONFIG_FRAME_POINTER=y. ip is saved as well if ever r12-clobbering + * trampoline are inserted by the linker and to keep sp 64-bit aligned. + */ +#define v7_exit_coherency_flush(level) \ + asm volatile( \ + ".arch armv7-a \n\t" \ + "stmfd sp!, {fp, ip} \n\t" \ + "mrc p15, 0, r0, c1, c0, 0 @ get SCTLR \n\t" \ + "bic r0, r0, #"__stringify(CR_C)" \n\t" \ + "mcr p15, 0, r0, c1, c0, 0 @ set SCTLR \n\t" \ + "isb \n\t" \ + "bl v7_flush_dcache_"__stringify(level)" \n\t" \ + "mrc p15, 0, r0, c1, c0, 1 @ get ACTLR \n\t" \ + "bic r0, r0, #(1 << 6) @ disable local coherency \n\t" \ + "mcr p15, 0, r0, c1, c0, 1 @ set ACTLR \n\t" \ + "isb \n\t" \ + "dsb \n\t" \ + "ldmfd sp!, {fp, ip}" \ + : : : "r0","r1","r2","r3","r4","r5","r6","r7", \ + "r9","r10","lr","memory" ) + +void flush_uprobe_xol_access(struct page *page, unsigned long uaddr, + void *kaddr, unsigned long len); + + +#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND +void check_cpu_icache_size(int cpuid); +#else +static inline void check_cpu_icache_size(int cpuid) { } +#endif + +#endif |