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| author | Valentine Barshak <vbarshak@mvista.com> | 2010-12-14 00:03:16 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-12-14 22:23:34 +0000 |
| commit | 85b093bcc5322baa811a03ec73de0909c157f181 (patch) | |
| tree | a403ad0cfc2c8d6dbeebc85d5332922410d2347c /arch | |
| parent | 593c252a731389ffdd00d4cb2d20192c47aa18c1 (diff) | |
| download | lwn-85b093bcc5322baa811a03ec73de0909c157f181.tar.gz lwn-85b093bcc5322baa811a03ec73de0909c157f181.zip | |
ARM: 6535/1: V6 MPCore v6_dma_inv_range and v6_dma_flush_range RWFO fix
Cache ownership must be acquired by reading/writing data from the
cache line to make cache operation have the desired effect on the
SMP MPCore CPU. However, the ownership is never acquired in the
v6_dma_inv_range function when cleaning the first line and
flushing the last one, in case the address is not aligned
to D_CACHE_LINE_SIZE boundary.
Fix this by reading/writing data if needed, before performing
cache operations.
While at it, fix v6_dma_flush_range to prevent RWFO outside
the buffer.
Cc: stable@kernel.org
Signed-off-by: Valentine Barshak <vbarshak@mvista.com>
Signed-off-by: George G. Davis <gdavis@mvista.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/mm/cache-v6.S | 28 |
1 files changed, 20 insertions, 8 deletions
diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S index 99fa688dfadd..c96fa1b3f49f 100644 --- a/arch/arm/mm/cache-v6.S +++ b/arch/arm/mm/cache-v6.S @@ -203,6 +203,10 @@ ENTRY(v6_flush_kern_dcache_area) * - 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 @@ -211,6 +215,10 @@ v6_dma_inv_range: mcrne p15, 0, r0, c7, c11, 1 @ clean unified line #endif tst r1, #D_CACHE_LINE_SIZE - 1 +#ifdef CONFIG_DMA_CACHE_RWFO + ldrneb r2, [r1, #-1] @ read for ownership + strneb 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 @@ -218,10 +226,6 @@ v6_dma_inv_range: mcrne p15, 0, r1, c7, c15, 1 @ clean & invalidate unified line #endif 1: -#ifdef CONFIG_DMA_CACHE_RWFO - 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 #else @@ -229,6 +233,10 @@ v6_dma_inv_range: #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 @@ -263,12 +271,12 @@ v6_dma_clean_range: * - end - virtual end address of region */ ENTRY(v6_dma_flush_range) - bic r0, r0, #D_CACHE_LINE_SIZE - 1 -1: #ifdef CONFIG_DMA_CACHE_RWFO - ldr r2, [r0] @ read for ownership - str r2, [r0] @ write for ownership + 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 @@ -276,6 +284,10 @@ ENTRY(v6_dma_flush_range) #endif add r0, r0, #D_CACHE_LINE_SIZE cmp r0, r1 +#ifdef CONFIG_DMA_CACHE_RWFO + ldrlob r2, [r0] @ read for ownership + strlob r2, [r0] @ write for ownership +#endif blo 1b mov r0, #0 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer |