ARC: dma: reintroduce platform specific dma<->phys

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/Kconfig

@@ -468,6 +468,9 @@ config ARCH_PHYS_ADDR_T_64BIT
 config ARCH_DMA_ADDR_T_64BIT
 	bool
 
+config ARC_PLAT_NEEDS_PHYS_TO_DMA
+	bool
+
 config ARC_CURR_IN_REG
 	bool "Dedicate Register r25 for current_task pointer"
 	default y

arch/arc/include/asm/dma-mapping.h

@@ -11,6 +11,13 @@
 #ifndef ASM_ARC_DMA_MAPPING_H
 #define ASM_ARC_DMA_MAPPING_H
 
+#ifndef CONFIG_ARC_PLAT_NEEDS_PHYS_TO_DMA
+#define plat_dma_to_phys(dev, dma_handle) ((phys_addr_t)(dma_handle))
+#define plat_phys_to_dma(dev, paddr) ((dma_addr_t)(paddr))
+#else
+#include <plat/dma.h>
+#endif
+
 extern struct dma_map_ops arc_dma_ops;
 
 static inline struct dma_map_ops *get_dma_ops(struct device *dev)

arch/arc/mm/dma.c

@@ -60,8 +60,7 @@ static void *arc_dma_alloc(struct device *dev, size_t size,
 	/* This is linear addr (0x8000_0000 based) */
 	paddr = page_to_phys(page);
 
-	/* For now bus address is exactly same as paddr */
-	*dma_handle = paddr;
+	*dma_handle = plat_phys_to_dma(dev, paddr);
 
 	/* This is kernel Virtual address (0x7000_0000 based) */
 	if (need_kvaddr) {
@@ -134,7 +133,7 @@ static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
 {
 	phys_addr_t paddr = page_to_phys(page) + offset;
 	_dma_cache_sync(paddr, size, dir);
-	return (dma_addr_t)paddr;
+	return plat_phys_to_dma(dev, paddr);
 }
 
 static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
@@ -153,13 +152,13 @@ static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
 static void arc_dma_sync_single_for_cpu(struct device *dev,
 		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
 {
-	_dma_cache_sync(dma_handle, size, DMA_FROM_DEVICE);
+	_dma_cache_sync(plat_dma_to_phys(dev, dma_handle), size, DMA_FROM_DEVICE);
 }
 
 static void arc_dma_sync_single_for_device(struct device *dev,
 		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
 {
-	_dma_cache_sync(dma_handle, size, DMA_TO_DEVICE);
+	_dma_cache_sync(plat_dma_to_phys(dev, dma_handle), size, DMA_TO_DEVICE);
 }
 
 static void arc_dma_sync_sg_for_cpu(struct device *dev,