In order to avoid passing random/junky values to DMA/HW as well as to allow simplifying memory initialization in individual drivers, chagnge dma_alloc_coherent() to guarantee that memory it returs is properly zeroed out. Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx> --- arch/arm/cpu/mmu-common.c | 3 ++- arch/arm/cpu/mmu-common.h | 1 + arch/arm/cpu/mmu.c | 2 +- arch/arm/cpu/mmu_64.c | 8 ++++++++ 4 files changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/arm/cpu/mmu-common.c b/arch/arm/cpu/mmu-common.c index c5b24bff8..aeefbb2da 100644 --- a/arch/arm/cpu/mmu-common.c +++ b/arch/arm/cpu/mmu-common.c @@ -43,7 +43,8 @@ void *dma_alloc_map(size_t size, dma_addr_t *dma_handle, unsigned flags) if (dma_handle) *dma_handle = (dma_addr_t)ret; - dma_inv_range(ret, size); + memset(ret, 0, size); + dma_flush_range(ret, size); arch_remap_range(ret, size, flags); diff --git a/arch/arm/cpu/mmu-common.h b/arch/arm/cpu/mmu-common.h index 679799c3c..0a33b138e 100644 --- a/arch/arm/cpu/mmu-common.h +++ b/arch/arm/cpu/mmu-common.h @@ -2,6 +2,7 @@ #define __ARM_MMU_COMMON_H void dma_inv_range(void *ptr, size_t size); +void dma_flush_range(void *ptr, size_t size); void *dma_alloc_map(size_t size, dma_addr_t *dma_handle, unsigned flags); void __mmu_init(bool mmu_on); diff --git a/arch/arm/cpu/mmu.c b/arch/arm/cpu/mmu.c index 9e261a0be..29816ad56 100644 --- a/arch/arm/cpu/mmu.c +++ b/arch/arm/cpu/mmu.c @@ -97,7 +97,7 @@ static u32 *find_pte(unsigned long adr) return &table[(adr >> PAGE_SHIFT) & 0xff]; } -static void dma_flush_range(void *ptr, size_t size) +void dma_flush_range(void *ptr, size_t size) { unsigned long start = (unsigned long)ptr; unsigned long end = start + size; diff --git a/arch/arm/cpu/mmu_64.c b/arch/arm/cpu/mmu_64.c index a3074b10d..b45a69661 100644 --- a/arch/arm/cpu/mmu_64.c +++ b/arch/arm/cpu/mmu_64.c @@ -233,6 +233,14 @@ void dma_inv_range(void *ptr, size_t size) v8_inv_dcache_range(start, end); } +void dma_flush_range(void *ptr, size_t size) +{ + unsigned long start = (unsigned long)ptr; + unsigned long end = start + size - 1; + + v8_flush_dcache_range(start, end); +} + void dma_sync_single_for_device(dma_addr_t address, size_t size, enum dma_data_direction dir) { -- 2.20.1 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox