diff options
| -rw-r--r-- | arch/arm64/include/asm/cache.h | 32 | ||||
| -rw-r--r-- | arch/arm64/include/asm/cacheflush.h | 148 | ||||
| -rw-r--r-- | arch/arm64/include/asm/cachetype.h | 48 | ||||
| -rw-r--r-- | arch/arm64/mm/cache.S | 168 | ||||
| -rw-r--r-- | arch/arm64/mm/flush.c | 135 |
5 files changed, 531 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h new file mode 100644 index 0000000..390308a --- /dev/null +++ b/arch/arm64/include/asm/cache.h @@ -0,0 +1,32 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_CACHE_H +#define __ASM_CACHE_H + +#define L1_CACHE_SHIFT 6 +#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) + +/* + * Memory returned by kmalloc() may be used for DMA, so we must make + * sure that all such allocations are cache aligned. Otherwise, + * unrelated code may cause parts of the buffer to be read into the + * cache before the transfer is done, causing old data to be seen by + * the CPU. + */ +#define ARCH_DMA_MINALIGN L1_CACHE_BYTES +#define ARCH_SLAB_MINALIGN 8 + +#endif diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h new file mode 100644 index 0000000..aa3132a --- /dev/null +++ b/arch/arm64/include/asm/cacheflush.h @@ -0,0 +1,148 @@ +/* + * Based on arch/arm/include/asm/cacheflush.h + * + * Copyright (C) 1999-2002 Russell King. + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_CACHEFLUSH_H +#define __ASM_CACHEFLUSH_H + +#include <linux/mm.h> + +/* + * 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/arm64/mm/cache.S implements these methods. + * + * Start addresses are inclusive and end addresses are exclusive; start + * addresses should be rounded down, end addresses up. + * + * See Documentation/cachetlb.txt for more information. Please note that + * the implementation assumes non-aliasing VIPT D-cache and (aliasing) + * VIPT or ASID-tagged VIVT I-cache. + * + * flush_cache_all() + * + * Unconditionally clean and invalidate the entire cache. + * + * flush_cache_mm(mm) + * + * Clean and invalidate all user space cache entries + * before a change of page tables. + * + * flush_icache_range(start, end) + * + * Ensure coherency between the I-cache and the D-cache in the + * region described by start, end. + * - start - virtual start address + * - end - virtual end address + * + * __flush_cache_user_range(start, end) + * + * Ensure coherency between the I-cache and the D-cache in the + * region described by start, end. + * - start - virtual start address + * - end - virtual end address + * + * __flush_dcache_area(kaddr, size) + * + * Ensure that the data held in page is written back. + * - kaddr - page address + * - size - region size + */ +extern void flush_cache_all(void); +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); +extern void flush_icache_range(unsigned long start, unsigned long end); +extern void __flush_dcache_area(void *addr, size_t len); +extern void __flush_cache_user_range(unsigned long start, unsigned long end); + +/* + * 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) + +#define flush_cache_dup_mm(mm) flush_cache_mm(mm) + +/* + * 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_icache_all(void) +{ + asm("ic ialluis"); +} + +#define flush_dcache_mmap_lock(mapping) \ + spin_lock_irq(&(mapping)->tree_lock) +#define flush_dcache_mmap_unlock(mapping) \ + spin_unlock_irq(&(mapping)->tree_lock) + +#define flush_icache_user_range(vma,page,addr,len) \ + flush_dcache_page(page) + +/* + * 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) +{ + /* + * set_pte_at() called from vmap_pte_range() does not + * have a DSB after cleaning the cache line. + */ + dsb(); +} + +static inline void flush_cache_vunmap(unsigned long start, unsigned long end) +{ +} + +#endif diff --git a/arch/arm64/include/asm/cachetype.h b/arch/arm64/include/asm/cachetype.h new file mode 100644 index 0000000..85f5f51 --- /dev/null +++ b/arch/arm64/include/asm/cachetype.h @@ -0,0 +1,48 @@ +/* + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_CACHETYPE_H +#define __ASM_CACHETYPE_H + +#include <asm/cputype.h> + +#define CTR_L1IP_SHIFT 14 +#define CTR_L1IP_MASK 3 + +#define ICACHE_POLICY_RESERVED 0 +#define ICACHE_POLICY_AIVIVT 1 +#define ICACHE_POLICY_VIPT 2 +#define ICACHE_POLICY_PIPT 3 + +static inline u32 icache_policy(void) +{ + return (read_cpuid_cachetype() >> CTR_L1IP_SHIFT) & CTR_L1IP_MASK; +} + +/* + * Whilst the D-side always behaves as PIPT on AArch64, aliasing is + * permitted in the I-cache. + */ +static inline int icache_is_aliasing(void) +{ + return icache_policy() != ICACHE_POLICY_PIPT; +} + +static inline int icache_is_aivivt(void) +{ + return icache_policy() == ICACHE_POLICY_AIVIVT; +} + +#endif /* __ASM_CACHETYPE_H */ diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S new file mode 100644 index 0000000..abe69b8 --- /dev/null +++ b/arch/arm64/mm/cache.S @@ -0,0 +1,168 @@ +/* + * Cache maintenance + * + * Copyright (C) 2001 Deep Blue Solutions Ltd. + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/assembler.h> + +#include "proc-macros.S" + +/* + * __flush_dcache_all() + * + * Flush the whole D-cache. + * + * Corrupted registers: x0-x7, x9-x11 + */ +ENTRY(__flush_dcache_all) + dsb sy // ensure ordering with previous memory accesses + mrs x0, clidr_el1 // read clidr + and x3, x0, #0x7000000 // extract loc from clidr + lsr x3, x3, #23 // left align loc bit field + cbz x3, finished // if loc is 0, then no need to clean + mov x10, #0 // start clean at cache level 0 +loop1: + add x2, x10, x10, lsr #1 // work out 3x current cache level + lsr x1, x0, x2 // extract cache type bits from clidr + and x1, x1, #7 // mask of the bits for current cache only + cmp x1, #2 // see what cache we have at this level + b.lt skip // skip if no cache, or just i-cache + save_and_disable_irqs x9 // make CSSELR and CCSIDR access atomic + msr csselr_el1, x10 // select current cache level in csselr + isb // isb to sych the new cssr&csidr + mrs x1, ccsidr_el1 // read the new ccsidr + restore_irqs x9 + and x2, x1, #7 // extract the length of the cache lines + add x2, x2, #4 // add 4 (line length offset) + mov x4, #0x3ff + and x4, x4, x1, lsr #3 // find maximum number on the way size + clz x5, x4 // find bit position of way size increment + mov x7, #0x7fff + and x7, x7, x1, lsr #13 // extract max number of the index size +loop2: + mov x9, x4 // create working copy of max way size +loop3: + lsl x6, x9, x5 + orr x11, x10, x6 // factor way and cache number into x11 + lsl x6, x7, x2 + orr x11, x11, x6 // factor index number into x11 + dc cisw, x11 // clean & invalidate by set/way + subs x9, x9, #1 // decrement the way + b.ge loop3 + subs x7, x7, #1 // decrement the index + b.ge loop2 +skip: + add x10, x10, #2 // increment cache number + cmp x3, x10 + b.gt loop1 +finished: + mov x10, #0 // swith back to cache level 0 + msr csselr_el1, x10 // select current cache level in csselr + dsb sy + isb + ret +ENDPROC(__flush_dcache_all) + +/* + * flush_cache_all() + * + * Flush the entire cache system. The data cache flush is now achieved + * using atomic clean / invalidates working outwards from L1 cache. This + * is done using Set/Way based cache maintainance instructions. The + * instruction cache can still be invalidated back to the point of + * unification in a single instruction. + */ +ENTRY(flush_cache_all) + mov x12, lr + bl __flush_dcache_all + mov x0, #0 + ic ialluis // I+BTB cache invalidate + ret x12 +ENDPROC(flush_cache_all) + +/* + * flush_icache_range(start,end) + * + * Ensure that the I and D caches are coherent within specified region. + * This is typically used when code has been written to a memory region, + * and will be executed. + * + * - start - virtual start address of region + * - end - virtual end address of region + */ +ENTRY(flush_icache_range) + /* FALLTHROUGH */ + +/* + * __flush_cache_user_range(start,end) + * + * Ensure that the I and D caches are coherent within specified region. + * This is typically used when code has been written to a memory region, + * and will be executed. + * + * - start - virtual start address of region + * - end - virtual end address of region + */ +ENTRY(__flush_cache_user_range) + dcache_line_size x2, x3 + sub x3, x2, #1 + bic x4, x0, x3 +1: +USER(9f, dc cvau, x4 ) // clean D line to PoU + add x4, x4, x2 + cmp x4, x1 + b.lo 1b + dsb sy + + icache_line_size x2, x3 + sub x3, x2, #1 + bic x4, x0, x3 +1: +USER(9f, ic ivau, x4 ) // invalidate I line PoU + add x4, x4, x2 + cmp x4, x1 + b.lo 1b +9: // ignore any faulting cache operation + dsb sy + isb + ret +ENDPROC(flush_icache_range) +ENDPROC(__flush_cache_user_range) + +/* + * __flush_kern_dcache_page(kaddr) + * + * Ensure that the data held in the page kaddr is written back to the + * page in question. + * + * - kaddr - kernel address + * - size - size in question + */ +ENTRY(__flush_dcache_area) + dcache_line_size x2, x3 + add x1, x0, x1 + sub x3, x2, #1 + bic x0, x0, x3 +1: dc civac, x0 // clean & invalidate D line / unified line + add x0, x0, x2 + cmp x0, x1 + b.lo 1b + dsb sy + ret +ENDPROC(__flush_dcache_area) diff --git a/arch/arm64/mm/flush.c b/arch/arm64/mm/flush.c new file mode 100644 index 0000000..c144adb --- /dev/null +++ b/arch/arm64/mm/flush.c @@ -0,0 +1,135 @@ +/* + * Based on arch/arm/mm/flush.c + * + * Copyright (C) 1995-2002 Russell King + * Copyright (C) 2012 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/pagemap.h> + +#include <asm/cacheflush.h> +#include <asm/cachetype.h> +#include <asm/tlbflush.h> + +#include "mm.h" + +void flush_cache_mm(struct mm_struct *mm) +{ +} + +void flush_cache_range(struct vm_area_struct *vma, unsigned long start, + unsigned long end) +{ + if (vma->vm_flags & VM_EXEC) + __flush_icache_all(); +} + +void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, + unsigned long pfn) +{ +} + +static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page, + unsigned long uaddr, void *kaddr, + unsigned long len) +{ + if (vma->vm_flags & VM_EXEC) { + unsigned long addr = (unsigned long)kaddr; + if (icache_is_aliasing()) { + __flush_dcache_area(kaddr, len); + __flush_icache_all(); + } else { + flush_icache_range(addr, addr + len); + } + } +} + +/* + * 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. + * + * Note that this code needs to run on the current CPU. + */ +void copy_to_user_page(struct vm_area_struct *vma, struct page *page, + unsigned long uaddr, void *dst, const void *src, + unsigned long len) +{ +#ifdef CONFIG_SMP + preempt_disable(); +#endif + memcpy(dst, src, len); + flush_ptrace_access(vma, page, uaddr, dst, len); +#ifdef CONFIG_SMP + preempt_enable(); +#endif +} + +void __flush_dcache_page(struct page *page) +{ + __flush_dcache_area(page_address(page), PAGE_SIZE); +} + +void __sync_icache_dcache(pte_t pte, unsigned long addr) +{ + unsigned long pfn; + struct page *page; + + pfn = pte_pfn(pte); + if (!pfn_valid(pfn)) + return; + + page = pfn_to_page(pfn); + if (!test_and_set_bit(PG_dcache_clean, &page->flags)) { + __flush_dcache_page(page); + __flush_icache_all(); + } else if (icache_is_aivivt()) { + __flush_icache_all(); + } +} + +/* + * Ensure cache coherency between kernel mapping and userspace mapping of this + * page. + */ +void flush_dcache_page(struct page *page) +{ + struct address_space *mapping; + + /* + * The zero page is never written to, so never has any dirty cache + * lines, and therefore never needs to be flushed. + */ + if (page == ZERO_PAGE(0)) + return; + + mapping = page_mapping(page); + if (mapping && mapping_mapped(mapping)) { + __flush_dcache_page(page); + __flush_icache_all(); + set_bit(PG_dcache_clean, &page->flags); + } else { + clear_bit(PG_dcache_clean, &page->flags); + } +} +EXPORT_SYMBOL(flush_dcache_page); + +/* + * Additional functions defined in assembly. + */ +EXPORT_SYMBOL(flush_cache_all); +EXPORT_SYMBOL(flush_icache_range); |
