/* * linux/arch/arm/mm/cache-v6.S * * Copyright (C) 2001 Deep Blue Solutions 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 is the "shell" of the ARMv6 processor support. */ #include <linux/linkage.h> #include <linux/init.h> #include <asm/assembler.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 #ifdef CONFIG_ARM_ERRATA_411920 /* * Invalidate the entire I cache (this code is a workaround for the 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_icache_inval_all) mov r0, #0 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 mov pc, lr #endif /* * 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_icache_inval_all #endif #else mcr p15, 0, r0, c7, c15, 0 @ Cache clean+invalidate #endif mov pc, 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) mov pc, 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 2: 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_icache_inval_all #endif #else mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB #endif mov pc, lr /* * Fault handling for the cache operation above. If the virtual address in r0 * isn't mapped, just try the next page. */ 9001: mov r0, r0, lsr #12 mov r0, r0, lsl #12 add r0, r0, #4096 b 2b 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 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 mov pc, 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: 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 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 CONFIG_SMP str r0, [r0] @ write for ownership #endif #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 blo 1b mov r0, #0 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer mov pc, 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_SMP 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 mov pc, lr /* * v6_dma_flush_range(start,end) * - start - virtual start address of region * - end - virtual end address of region */ ENTRY(v6_dma_flush_range) bic r0, r0, #D_CACHE_LINE_SIZE - 1 1: #ifdef CONFIG_SMP ldr r2, [r0] @ read for ownership str r2, [r0] @ write for ownership #endif #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 blo 1b mov r0, #0 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer mov pc, 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 teq r2, #DMA_TO_DEVICE beq v6_dma_clean_range b v6_dma_flush_range 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) mov pc, lr ENDPROC(v6_dma_unmap_area) __INITDATA .type v6_cache_fns, #object ENTRY(v6_cache_fns) .long v6_flush_kern_cache_all .long v6_flush_user_cache_all .long v6_flush_user_cache_range .long v6_coherent_kern_range .long v6_coherent_user_range .long v6_flush_kern_dcache_area .long v6_dma_map_area .long v6_dma_unmap_area .long v6_dma_flush_range .size v6_cache_fns, . - v6_cache_fns