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Diffstat (limited to 'arch/arm/mm/cache-v6.S')
| -rw-r--r-- | arch/arm/mm/cache-v6.S | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S new file mode 100644 index 000000000..f0f65eb07 --- /dev/null +++ b/arch/arm/mm/cache-v6.S @@ -0,0 +1,332 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * linux/arch/arm/mm/cache-v6.S + * + * Copyright (C) 2001 Deep Blue Solutions Ltd. + * + * This is the "shell" of the ARMv6 processor support. + */ +#include <linux/linkage.h> +#include <linux/init.h> +#include <asm/assembler.h> +#include <asm/errno.h> +#include <asm/unwind.h> + +#include "proc-macros.S" + +#define HARVARD_CACHE +#define CACHE_LINE_SIZE 32 +#define D_CACHE_LINE_SIZE 32 +#define BTB_FLUSH_SIZE 8 + +/* + * v6_flush_icache_all() + * + * Flush the whole I-cache. + * + * ARM1136 erratum 411920 - Invalidate Instruction Cache operation can fail. + * This erratum is present in 1136, 1156 and 1176. It does not affect the + * MPCore. + * + * Registers: + * r0 - set to 0 + * r1 - corrupted + */ +ENTRY(v6_flush_icache_all) + mov r0, #0 +#ifdef CONFIG_ARM_ERRATA_411920 + mrs r1, cpsr + cpsid ifa @ disable interrupts + mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache + mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache + mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache + mcr p15, 0, r0, c7, c5, 0 @ invalidate entire I-cache + msr cpsr_cx, r1 @ restore interrupts + .rept 11 @ ARM Ltd recommends at least + nop @ 11 NOPs + .endr +#else + mcr p15, 0, r0, c7, c5, 0 @ invalidate I-cache +#endif + ret lr +ENDPROC(v6_flush_icache_all) + +/* + * v6_flush_cache_all() + * + * Flush the entire cache. + * + * It is assumed that: + */ +ENTRY(v6_flush_kern_cache_all) + mov r0, #0 +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c14, 0 @ D cache clean+invalidate +#ifndef CONFIG_ARM_ERRATA_411920 + mcr p15, 0, r0, c7, c5, 0 @ I+BTB cache invalidate +#else + b v6_flush_icache_all +#endif +#else + mcr p15, 0, r0, c7, c15, 0 @ Cache clean+invalidate +#endif + ret lr + +/* + * v6_flush_cache_all() + * + * Flush all TLB entries in a particular address space + * + * - mm - mm_struct describing address space + */ +ENTRY(v6_flush_user_cache_all) + /*FALLTHROUGH*/ + +/* + * v6_flush_cache_range(start, end, flags) + * + * Flush a range of TLB entries in the specified address space. + * + * - start - start address (may not be aligned) + * - end - end address (exclusive, may not be aligned) + * - flags - vm_area_struct flags describing address space + * + * It is assumed that: + * - we have a VIPT cache. + */ +ENTRY(v6_flush_user_cache_range) + ret lr + +/* + * v6_coherent_kern_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 + * + * It is assumed that: + * - the Icache does not read data from the write buffer + */ +ENTRY(v6_coherent_kern_range) + /* FALLTHROUGH */ + +/* + * v6_coherent_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 + * + * It is assumed that: + * - the Icache does not read data from the write buffer + */ +ENTRY(v6_coherent_user_range) + UNWIND(.fnstart ) +#ifdef HARVARD_CACHE + bic r0, r0, #CACHE_LINE_SIZE - 1 +1: + USER( mcr p15, 0, r0, c7, c10, 1 ) @ clean D line + add r0, r0, #CACHE_LINE_SIZE + cmp r0, r1 + blo 1b +#endif + mov r0, #0 +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer +#ifndef CONFIG_ARM_ERRATA_411920 + mcr p15, 0, r0, c7, c5, 0 @ I+BTB cache invalidate +#else + b v6_flush_icache_all +#endif +#else + mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB +#endif + ret lr + +/* + * Fault handling for the cache operation above. If the virtual address in r0 + * isn't mapped, fail with -EFAULT. + */ +9001: + mov r0, #-EFAULT + ret lr + UNWIND(.fnend ) +ENDPROC(v6_coherent_user_range) +ENDPROC(v6_coherent_kern_range) + +/* + * v6_flush_kern_dcache_area(void *addr, size_t size) + * + * Ensure that the data held in the page kaddr is written back + * to the page in question. + * + * - addr - kernel address + * - size - region size + */ +ENTRY(v6_flush_kern_dcache_area) + add r1, r0, r1 + bic r0, r0, #D_CACHE_LINE_SIZE - 1 +1: +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D line +#else + mcr p15, 0, r0, c7, c15, 1 @ clean & invalidate unified line +#endif + add r0, r0, #D_CACHE_LINE_SIZE + cmp r0, r1 + blo 1b +#ifdef HARVARD_CACHE + mov r0, #0 + mcr p15, 0, r0, c7, c10, 4 +#endif + ret lr + + +/* + * v6_dma_inv_range(start,end) + * + * Invalidate the data cache within the specified region; we will + * be performing a DMA operation in this region and we want to + * purge old data in the cache. + * + * - start - virtual start address of region + * - end - virtual end address of region + */ +v6_dma_inv_range: +#ifdef CONFIG_DMA_CACHE_RWFO + ldrb r2, [r0] @ read for ownership + strb r2, [r0] @ write for ownership +#endif + tst r0, #D_CACHE_LINE_SIZE - 1 + bic r0, r0, #D_CACHE_LINE_SIZE - 1 +#ifdef HARVARD_CACHE + mcrne p15, 0, r0, c7, c10, 1 @ clean D line +#else + mcrne p15, 0, r0, c7, c11, 1 @ clean unified line +#endif + tst r1, #D_CACHE_LINE_SIZE - 1 +#ifdef CONFIG_DMA_CACHE_RWFO + ldrbne r2, [r1, #-1] @ read for ownership + strbne r2, [r1, #-1] @ write for ownership +#endif + bic r1, r1, #D_CACHE_LINE_SIZE - 1 +#ifdef HARVARD_CACHE + mcrne p15, 0, r1, c7, c14, 1 @ clean & invalidate D line +#else + mcrne p15, 0, r1, c7, c15, 1 @ clean & invalidate unified line +#endif +1: +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c6, 1 @ invalidate D line +#else + mcr p15, 0, r0, c7, c7, 1 @ invalidate unified line +#endif + add r0, r0, #D_CACHE_LINE_SIZE + cmp r0, r1 +#ifdef CONFIG_DMA_CACHE_RWFO + ldrlo r2, [r0] @ read for ownership + strlo r2, [r0] @ write for ownership +#endif + blo 1b + mov r0, #0 + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer + ret lr + +/* + * v6_dma_clean_range(start,end) + * - start - virtual start address of region + * - end - virtual end address of region + */ +v6_dma_clean_range: + bic r0, r0, #D_CACHE_LINE_SIZE - 1 +1: +#ifdef CONFIG_DMA_CACHE_RWFO + ldr r2, [r0] @ read for ownership +#endif +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c10, 1 @ clean D line +#else + mcr p15, 0, r0, c7, c11, 1 @ clean unified line +#endif + add r0, r0, #D_CACHE_LINE_SIZE + cmp r0, r1 + blo 1b + mov r0, #0 + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer + ret lr + +/* + * v6_dma_flush_range(start,end) + * - start - virtual start address of region + * - end - virtual end address of region + */ +ENTRY(v6_dma_flush_range) +#ifdef CONFIG_DMA_CACHE_RWFO + ldrb r2, [r0] @ read for ownership + strb r2, [r0] @ write for ownership +#endif + bic r0, r0, #D_CACHE_LINE_SIZE - 1 +1: +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D line +#else + mcr p15, 0, r0, c7, c15, 1 @ clean & invalidate line +#endif + add r0, r0, #D_CACHE_LINE_SIZE + cmp r0, r1 +#ifdef CONFIG_DMA_CACHE_RWFO + ldrblo r2, [r0] @ read for ownership + strblo r2, [r0] @ write for ownership +#endif + blo 1b + mov r0, #0 + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer + ret lr + +/* + * dma_map_area(start, size, dir) + * - start - kernel virtual start address + * - size - size of region + * - dir - DMA direction + */ +ENTRY(v6_dma_map_area) + add r1, r1, r0 + teq r2, #DMA_FROM_DEVICE + beq v6_dma_inv_range +#ifndef CONFIG_DMA_CACHE_RWFO + b v6_dma_clean_range +#else + teq r2, #DMA_TO_DEVICE + beq v6_dma_clean_range + b v6_dma_flush_range +#endif +ENDPROC(v6_dma_map_area) + +/* + * dma_unmap_area(start, size, dir) + * - start - kernel virtual start address + * - size - size of region + * - dir - DMA direction + */ +ENTRY(v6_dma_unmap_area) +#ifndef CONFIG_DMA_CACHE_RWFO + add r1, r1, r0 + teq r2, #DMA_TO_DEVICE + bne v6_dma_inv_range +#endif + ret lr +ENDPROC(v6_dma_unmap_area) + + .globl v6_flush_kern_cache_louis + .equ v6_flush_kern_cache_louis, v6_flush_kern_cache_all + + __INITDATA + + @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S) + define_cache_functions v6 |