[ARM] Move DMA mask-based bounce detection to dmabounce code.

arch/arm/common/dmabounce.c

@@ -216,27 +216,33 @@ static inline dma_addr_t
 map_single(struct device *dev, void *ptr, size_t size,
 		enum dma_data_direction dir)
 {
-	dma_addr_t dma_addr;
 	struct dmabounce_device_info *device_info = find_dmabounce_dev(dev);
+	dma_addr_t dma_addr;
+	int needs_bounce = 0;
 
 	if (device_info)
 		DO_STATS ( device_info->map_op_count++ );
 
+	dma_addr = virt_to_dma(dev, ptr);
+
 	if (dev->dma_mask) {
+		unsigned long mask = *dev->dma_mask;
 		unsigned long limit;
 
-		limit = (*dev->dma_mask + 1) & ~(*dev->dma_mask);
-		if (limit && (size > limit)) {
-			dev_err(dev, "DMA mapping too big "
-				"(requested %#x mask %#Lx)\n",
-				size, *dev->dma_mask);
+		limit = (mask + 1) & ~mask;
+		if (limit && size > limit) {
+			dev_err(dev, "DMA mapping too big (requested %#x "
+				"mask %#Lx)\n", size, *dev->dma_mask);
 			return ~0;
 		}
-	}
 
-	dma_addr = virt_to_dma(dev, ptr);
+		/*
+		 * Figure out if we need to bounce from the DMA mask.
+		 */
+		needs_bounce = (dma_addr | (dma_addr + size - 1)) & ~mask;
+	}
 
-	if (device_info && dma_needs_bounce(dev, dma_addr, size)) {
+	if (device_info && (needs_bounce || dma_needs_bounce(dev, dma_addr, size))) {
 		struct safe_buffer *buf;
 
 		buf = alloc_safe_buffer(device_info, ptr, size, dir);

arch/arm/common/sa1111.c

@@ -761,9 +761,6 @@ static void __sa1111_remove(struct sa1111 *sachip)
  */
 int dma_needs_bounce(struct device *dev, dma_addr_t addr, size_t size)
 {
-	unsigned int physaddr = SA1111_DMA_ADDR((unsigned int)addr);
-	u32 dma_mask = *dev->dma_mask;
-
 	/*
 	 * Section 4.6 of the "Intel StrongARM SA-1111 Development Module
 	 * User's Guide" mentions that jumpers R51 and R52 control the
@@ -771,14 +768,8 @@ int dma_needs_bounce(struct device *dev, dma_addr_t addr, size_t size)
 	 * SDRAM bank 1 on Neponset). The default configuration selects
 	 * Assabet, so any address in bank 1 is necessarily invalid.
 	 */
-	if ((machine_is_assabet() || machine_is_pfs168()) &&
-		(addr >= 0xc8000000 || (addr + size) >= 0xc8000000))
-	  	return 1;
-
-	/*
-	 * Check to see if either the start or end are illegal.
-	 */
-	return ((addr & ~dma_mask)) || ((addr + size - 1) & ~dma_mask);
+	return ((machine_is_assabet() || machine_is_pfs168()) &&
+		(addr >= 0xc8000000 || (addr + size) >= 0xc8000000));
 }
 
 struct sa1111_save_data {