Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394...

[pandora-kernel.git] / arch / powerpc / lib / dma-noncoherent.c

diff --git a/arch/powerpc/lib/dma-noncoherent.c b/arch/powerpc/lib/dma-noncoherent.c
index 6656d47..5d83907 100644 (file)
--- a/arch/powerpc/lib/dma-noncoherent.c
+++ b/arch/powerpc/lib/dma-noncoherent.c
@@ -348,8 +348,15 @@ void __dma_sync(void *vaddr, size_t size, int direction)
        switch (direction) {
        case DMA_NONE:
                BUG();
-       case DMA_FROM_DEVICE:   /* invalidate only */
-               invalidate_dcache_range(start, end);
+       case DMA_FROM_DEVICE:
+               /*
+                * invalidate only when cache-line aligned otherwise there is
+                * the potential for discarding uncommitted data from the cache
+                */
+               if ((start & (L1_CACHE_BYTES - 1)) || (size & (L1_CACHE_BYTES - 1)))
+                       flush_dcache_range(start, end);
+               else
+                       invalidate_dcache_range(start, end);
                break;
        case DMA_TO_DEVICE:             /* writeback only */
                clean_dcache_range(start, end);