[PATCH 3/7] Use archdata.dma_data in dma_direct_ops and add the offset

[Michael Ellerman]

Now that all platforms using dma_direct_offset setup the archdata.dma_data
correctly, we can change the dma_direct_ops to retrieve the offset from
the dma_data, rather than directly from the global.

While we're here, change the way the offset is used - instead of or'ing it
into the value, add it. This should have no effect on current implementations
where the offset is far larger than memory, however in future we may want
to use smaller offsets.

Signed-off-by: Michael Ellerman <michael at ellerman.id.au>
---
 arch/powerpc/kernel/dma_64.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/dma_64.c b/arch/powerpc/kernel/dma_64.c
index 14206e3..a2d076d 100644
--- a/arch/powerpc/kernel/dma_64.c
+++ b/arch/powerpc/kernel/dma_64.c
@@ -117,6 +117,11 @@ EXPORT_SYMBOL(dma_iommu_ops);
  */
 unsigned long dma_direct_offset;
 
+static unsigned long get_dma_direct_offset(struct device *dev)
+{
+	return (unsigned long)dev->archdata.dma_data;
+}
+
 static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
 				       dma_addr_t *dma_handle, gfp_t flag)
 {
@@ -130,7 +135,7 @@ static 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) | dma_direct_offset;
+	*dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev);
 
 	return ret;
 }
@@ -145,7 +150,7 @@ static dma_addr_t dma_direct_map_single(struct device *dev, void *ptr,
 					size_t size,
 					enum dma_data_direction direction)
 {
-	return virt_to_abs(ptr) | dma_direct_offset;
+	return virt_to_abs(ptr) + get_dma_direct_offset(dev);
 }
 
 static void dma_direct_unmap_single(struct device *dev, dma_addr_t dma_addr,
@@ -161,7 +166,7 @@ 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) | dma_direct_offset;
+		sg->dma_address = sg_phys(sg) + get_dma_direct_offset(dev);
 		sg->dma_length = sg->length;
 	}
 
-- 
1.5.2.rc1.1884.g59b20