[ARM] Optionally flush entire dcache from v6_dma_flush_range

If CACHE_FLUSH_RANGE_LIMIT is defined, then the entire dcache will
be flushed if the requested range is larger than this limit.

Change-Id: I29277d645a9d6716b1952cf3b870c78496261dd0
Signed-off-by: Arve Hjønnevåg <arve@android.com>

diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S
index d8fd4d4bd3d45ecdc66ad2c74885795df9681ea7..7a3d3d8d98d7fa384e998d271b1ccbbf5b3de256 100644 (file)
--- a/arch/arm/mm/cache-v6.S
+++ b/arch/arm/mm/cache-v6.S
@@ -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
        mov     pc, 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