powerpc: Rename get_dma_direct_offset get_dma_offset

The former is no longer really accurate with the swiotlb case now
a possibility.  I also move it into dma-mapping.h - it no longer
needs to be in dma.c, and there are about to be some more accessors
that should all end up in the same place.  A comment is added to
indicate that this function is not used in configs where there is no
simple dma offset, such as the iommu case.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 4 insertions, 11 deletions

diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index 21b784d7e7d0..6215062caf8c 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -21,13 +21,6 @@
  * default the offset is PCI_DRAM_OFFSET.
  */
 
-unsigned long get_dma_direct_offset(struct device *dev)
-{
-        if (dev)
-                return (unsigned long)dev->archdata.dma_data;
-
-        return PCI_DRAM_OFFSET;
-}
 
 void *dma_direct_alloc_coherent(struct device *dev, size_t size,
                                 dma_addr_t *dma_handle, gfp_t flag)
@@ -37,7 +30,7 @@ void *dma_direct_alloc_coherent(struct device *dev, size_t size,
         ret = __dma_alloc_coherent(dev, size, dma_handle, flag);
         if (ret == NULL)
                 return NULL;
-        *dma_handle += get_dma_direct_offset(dev);
+        *dma_handle += get_dma_offset(dev);
         return ret;
 #else
         struct page *page;
@@ -51,7 +44,7 @@ void *dma_direct_alloc_coherent(struct device *dev, size_t size,
                 return NULL;
         ret = page_address(page);
         memset(ret, 0, size);
-        *dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev);
+        *dma_handle = virt_to_abs(ret) + get_dma_offset(dev);
 
         return ret;
 #endif
@@ -75,7 +68,7 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
         int i;
 
         for_each_sg(sgl, sg, nents, i) {
-                sg->dma_address = sg_phys(sg) + get_dma_direct_offset(dev);
+                sg->dma_address = sg_phys(sg) + get_dma_offset(dev);
                 sg->dma_length = sg->length;
                 __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
         }
@@ -110,7 +103,7 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
 {
         BUG_ON(dir == DMA_NONE);
         __dma_sync_page(page, offset, size, dir);
-        return page_to_phys(page) + offset + get_dma_direct_offset(dev);
+        return page_to_phys(page) + offset + get_dma_offset(dev);
 }
 
 static inline void dma_direct_unmap_page(struct device *dev,