From: Catalin Marinas Date: Mon, 21 Jun 2010 14:09:36 +0000 (+0100) Subject: ARM: 6187/1: The v6_dma_inv_range() function must preserve data on SMP X-Git-Tag: v3.0~4285^2~10 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ca57926d53580f7c950496cb7ef6d7930610e1dd;p=platform%2Fkernel%2Flinux-amlogic.git ARM: 6187/1: The v6_dma_inv_range() function must preserve data on SMP A recent patch for DMA cache maintenance on ARM11MPCore added a write for ownership trick to the v6_dma_inv_range() function. Such operation destroys data already present in the buffer. However, this function is used with with dma_sync_single_for_device() which is supposed to preserve the existing data transfered into the buffer. This patch adds a combination of read/write for ownership to preserve the original data. Reported-by: Ronen Shitrit Signed-off-by: Catalin Marinas Signed-off-by: Russell King --- diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S index e46ecd8..332b48c 100644 --- a/arch/arm/mm/cache-v6.S +++ b/arch/arm/mm/cache-v6.S @@ -212,7 +212,8 @@ v6_dma_inv_range: #endif 1: #ifdef CONFIG_SMP - str r0, [r0] @ write for ownership + ldr r2, [r0] @ read for ownership + str r2, [r0] @ write for ownership #endif #ifdef HARVARD_CACHE mcr p15, 0, r0, c7, c6, 1 @ invalidate D line