ARC: remove the unused platform helpers from dma mapping API

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

arch/arc/mm/dma.c

@@ -14,8 +14,6 @@
  * Cache bit off in the TLB entry.
  *
  * The default DMA address == Phy address which is 0x8000_0000 based.
- * A platform/device can make it zero based, by over-riding
- * plat_{dma,kernel}_addr_to_{kernel,dma}
  */
 
 #include <linux/dma-mapping.h>
@@ -37,7 +35,7 @@ void *dma_alloc_noncoherent(struct device *dev, size_t size,
 		return NULL;
 
 	/* This is bus address, platform dependent */
-	*dma_handle = plat_kernel_addr_to_dma(dev, paddr);
+	*dma_handle = (dma_addr_t)paddr;
 
 	return paddr;
 }
@@ -46,8 +44,7 @@ EXPORT_SYMBOL(dma_alloc_noncoherent);
 void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
 			  dma_addr_t dma_handle)
 {
-	free_pages_exact((void *)plat_dma_addr_to_kernel(dev, dma_handle),
-			 size);
+	free_pages_exact((void *)dma_handle, size);
 }
 EXPORT_SYMBOL(dma_free_noncoherent);
 
@@ -67,7 +64,7 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
 		memset(kvaddr, 0, size);
 
 	/* This is bus address, platform dependent */
-	*dma_handle = plat_kernel_addr_to_dma(dev, paddr);
+	*dma_handle = (dma_addr_t)paddr;
 
 	return kvaddr;
 }
@@ -78,8 +75,7 @@ void dma_free_coherent(struct device *dev, size_t size, void *kvaddr,
 {
 	iounmap((void __force __iomem *)kvaddr);
 
-	free_pages_exact((void *)plat_dma_addr_to_kernel(dev, dma_handle),
-			 size);
+	free_pages_exact((void *)dma_handle, size);
 }
 EXPORT_SYMBOL(dma_free_coherent);