diff -drupN a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S --- a/arch/arm/mm/cache-v6.S 2018-08-06 17:23:04.000000000 +0300 +++ b/arch/arm/mm/cache-v6.S 2022-06-12 05:28:14.000000000 +0300 @@ -270,6 +270,11 @@ v6_dma_clean_range: * - end - virtual end address of region */ ENTRY(v6_dma_flush_range) +#ifdef CONFIG_CACHE_FLUSH_RANGE_LIMIT + sub r2, r1, r0 + cmp r2, #CONFIG_CACHE_FLUSH_RANGE_LIMIT + bhi v6_dma_flush_dcache_all +#endif #ifdef CONFIG_DMA_CACHE_RWFO ldrb r2, [r0] @ read for ownership strb r2, [r0] @ write for ownership @@ -292,6 +297,18 @@ ENTRY(v6_dma_flush_range) mcr p15, 0, r0, c7, c10, 4 @ drain write buffer ret lr +#ifdef CONFIG_CACHE_FLUSH_RANGE_LIMIT +v6_dma_flush_dcache_all: + mov r0, #0 +#ifdef HARVARD_CACHE + mcr p15, 0, r0, c7, c14, 0 @ D cache clean+invalidate +#else + mcr p15, 0, r0, c7, c15, 0 @ Cache clean+invalidate +#endif + mcr p15, 0, r0, c7, c10, 4 @ drain write buffer + mov pc, lr +#endif + /* * dma_map_area(start, size, dir) * - start - kernel virtual start address