diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/arm/mm/cache-v4wb.S | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/arch/arm/mm/cache-v4wb.S b/arch/arm/mm/cache-v4wb.S new file mode 100644 index 0000000000..ad382cee0f --- /dev/null +++ b/arch/arm/mm/cache-v4wb.S @@ -0,0 +1,258 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/mm/cache-v4wb.S + * + * Copyright (C) 1997-2002 Russell king + */ +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/assembler.h> +#include <asm/page.h> +#include "proc-macros.S" + +/* + * The size of one data cache line. + */ +#define CACHE_DLINESIZE 32 + +/* + * The total size of the data cache. + */ +#if defined(CONFIG_CPU_SA110) +# define CACHE_DSIZE 16384 +#elif defined(CONFIG_CPU_SA1100) +# define CACHE_DSIZE 8192 +#else +# error Unknown cache size +#endif + +/* + * This is the size at which it becomes more efficient to + * clean the whole cache, rather than using the individual + * cache line maintenance instructions. + * + * Size Clean (ticks) Dirty (ticks) + * 4096 21 20 21 53 55 54 + * 8192 40 41 40 106 100 102 + * 16384 77 77 76 140 140 138 + * 32768 150 149 150 214 216 212 <--- + * 65536 296 297 296 351 358 361 + * 131072 591 591 591 656 657 651 + * Whole 132 136 132 221 217 207 <--- + */ +#define CACHE_DLIMIT (CACHE_DSIZE * 4) + + .data + .align 2 +flush_base: + .long FLUSH_BASE + .text + +/* + * flush_icache_all() + * + * Unconditionally clean and invalidate the entire icache. + */ +ENTRY(v4wb_flush_icache_all) + mov r0, #0 + mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache + ret lr +ENDPROC(v4wb_flush_icache_all) + +/* + * flush_user_cache_all() + * + * Clean and invalidate all cache entries in a particular address + * space. + */ +ENTRY(v4wb_flush_user_cache_all) + /* FALLTHROUGH */ +/* + * flush_kern_cache_all() + * + * Clean and invalidate the entire cache. + */ +ENTRY(v4wb_flush_kern_cache_all) + mov ip, #0 + mcr p15, 0, ip, c7, c5, 0 @ invalidate I cache +__flush_whole_cache: + ldr r3, =flush_base + ldr r1, [r3, #0] + eor r1, r1, #CACHE_DSIZE + str r1, [r3, #0] + add r2, r1, #CACHE_DSIZE +1: ldr r3, [r1], #32 + cmp r1, r2 + blo 1b +#ifdef FLUSH_BASE_MINICACHE + add r2, r2, #FLUSH_BASE_MINICACHE - FLUSH_BASE + sub r1, r2, #512 @ only 512 bytes +1: ldr r3, [r1], #32 + cmp r1, r2 + blo 1b +#endif + mcr p15, 0, ip, c7, c10, 4 @ drain write buffer + ret lr + +/* + * flush_user_cache_range(start, end, flags) + * + * Invalidate a range of cache entries in the specified + * address space. + * + * - start - start address (inclusive, page aligned) + * - end - end address (exclusive, page aligned) + * - flags - vma_area_struct flags describing address space + */ +ENTRY(v4wb_flush_user_cache_range) + mov ip, #0 + sub r3, r1, r0 @ calculate total size + tst r2, #VM_EXEC @ executable region? + mcrne p15, 0, ip, c7, c5, 0 @ invalidate I cache + + cmp r3, #CACHE_DLIMIT @ total size >= limit? + bhs __flush_whole_cache @ flush whole D cache + +1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry + mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry + add r0, r0, #CACHE_DLINESIZE + cmp r0, r1 + blo 1b + tst r2, #VM_EXEC + mcrne p15, 0, ip, c7, c10, 4 @ drain write buffer + ret lr + +/* + * flush_kern_dcache_area(void *addr, size_t size) + * + * Ensure no D cache aliasing occurs, either with itself or + * the I cache + * + * - addr - kernel address + * - size - region size + */ +ENTRY(v4wb_flush_kern_dcache_area) + add r1, r0, r1 + /* fall through */ + +/* + * coherent_kern_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start. If you have non-snooping + * Harvard caches, you need to implement this function. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(v4wb_coherent_kern_range) + /* fall through */ + +/* + * coherent_user_range(start, end) + * + * Ensure coherency between the Icache and the Dcache in the + * region described by start. If you have non-snooping + * Harvard caches, you need to implement this function. + * + * - start - virtual start address + * - end - virtual end address + */ +ENTRY(v4wb_coherent_user_range) + bic r0, r0, #CACHE_DLINESIZE - 1 +1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry + mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry + add r0, r0, #CACHE_DLINESIZE + cmp r0, r1 + blo 1b + mov r0, #0 + mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache + mcr p15, 0, r0, c7, c10, 4 @ drain WB + ret lr + + +/* + * dma_inv_range(start, end) + * + * Invalidate (discard) the specified virtual address range. + * May not write back any entries. If 'start' or 'end' + * are not cache line aligned, those lines must be written + * back. + * + * - start - virtual start address + * - end - virtual end address + */ +v4wb_dma_inv_range: + tst r0, #CACHE_DLINESIZE - 1 + bic r0, r0, #CACHE_DLINESIZE - 1 + mcrne p15, 0, r0, c7, c10, 1 @ clean D entry + tst r1, #CACHE_DLINESIZE - 1 + mcrne p15, 0, r1, c7, c10, 1 @ clean D entry +1: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry + add r0, r0, #CACHE_DLINESIZE + cmp r0, r1 + blo 1b + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer + ret lr + +/* + * dma_clean_range(start, end) + * + * Clean (write back) the specified virtual address range. + * + * - start - virtual start address + * - end - virtual end address + */ +v4wb_dma_clean_range: + bic r0, r0, #CACHE_DLINESIZE - 1 +1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry + add r0, r0, #CACHE_DLINESIZE + cmp r0, r1 + blo 1b + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer + ret lr + +/* + * dma_flush_range(start, end) + * + * Clean and invalidate the specified virtual address range. + * + * - start - virtual start address + * - end - virtual end address + * + * This is actually the same as v4wb_coherent_kern_range() + */ + .globl v4wb_dma_flush_range + .set v4wb_dma_flush_range, v4wb_coherent_kern_range + +/* + * dma_map_area(start, size, dir) + * - start - kernel virtual start address + * - size - size of region + * - dir - DMA direction + */ +ENTRY(v4wb_dma_map_area) + add r1, r1, r0 + cmp r2, #DMA_TO_DEVICE + beq v4wb_dma_clean_range + bcs v4wb_dma_inv_range + b v4wb_dma_flush_range +ENDPROC(v4wb_dma_map_area) + +/* + * dma_unmap_area(start, size, dir) + * - start - kernel virtual start address + * - size - size of region + * - dir - DMA direction + */ +ENTRY(v4wb_dma_unmap_area) + ret lr +ENDPROC(v4wb_dma_unmap_area) + + .globl v4wb_flush_kern_cache_louis + .equ v4wb_flush_kern_cache_louis, v4wb_flush_kern_cache_all + + __INITDATA + + @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S) + define_cache_functions v4wb |