1 files changed, 11 insertions, 4 deletions

diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 44d47ac552a9..05c101e7dcd7 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -1026,9 +1026,12 @@ static int dma_set_mask_pSeriesLP(struct device *dev, u64 dma_mask)
         const void *dma_window = NULL;
         u64 dma_offset;
 
-        if (!dev->dma_mask || !dma_supported(dev, dma_mask))
+        if (!dev->dma_mask)
                 return -EIO;
 
+        if (!dev_is_pci(dev))
+                goto check_mask;
+
         pdev = to_pci_dev(dev);
 
         /* only attempt to use a new window if 64-bit DMA is requested */
@@ -1059,13 +1062,17 @@ static int dma_set_mask_pSeriesLP(struct device *dev, u64 dma_mask)
                 }
         }
 
-        /* fall-through to iommu ops */
-        if (!ddw_enabled) {
-                dev_info(dev, "Using 32-bit DMA via iommu\n");
+        /* fall back on iommu ops, restore table pointer with ops */
+        if (!ddw_enabled && get_dma_ops(dev) != &dma_iommu_ops) {
+                dev_info(dev, "Restoring 32-bit DMA via iommu\n");
                 set_dma_ops(dev, &dma_iommu_ops);
                 pci_dma_dev_setup_pSeriesLP(pdev);
         }
 
+check_mask:
+        if (!dma_supported(dev, dma_mask))
+                return -EIO;
+
         *dev->dma_mask = dma_mask;
         return 0;
 }