gpu: nvgpu: detect iommu'ability dynamically

A device can be iommu'able whenever it's registered so that this patch
detects its iommu'ability dynamically.

Bug 1577389

Change-Id: I8ea20e5dd997fc1a399f517c17783323f238ecc3
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Reviewed-on: http://git-master/r/606019
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
index 03a5dabb..9fdbf2b7 100644
--- a/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/mm_gk20a.c
@@ -1664,14 +1664,16 @@ u64 gk20a_mm_smmu_vaddr_translate(struct gk20a *g, dma_addr_t iova)
 
 u64 gk20a_mm_iova_addr(struct gk20a *g, struct scatterlist *sgl)
 {
-        u64 result = sg_phys(sgl);
-#ifdef CONFIG_TEGRA_IOMMU_SMMU
+        if (!device_is_iommuable(dev_from_gk20a(g)))
+                return sg_phys(sgl);
+
+        if (sg_dma_address(sgl) == 0)
+                return sg_phys(sgl);
+
         if (sg_dma_address(sgl) == DMA_ERROR_CODE)
-                result = 0;
-        else if (sg_dma_address(sgl))
-                result = gk20a_mm_smmu_vaddr_translate(g, sg_dma_address(sgl));
-#endif
-        return result;
+                return 0;
+
+        return gk20a_mm_smmu_vaddr_translate(g, sg_dma_address(sgl));
 }
 
 static int update_gmmu_ptes_locked(struct vm_gk20a *vm,