- if (!dev->dma_mask || !dma_supported(dev, dma_mask))
- return -EIO;
-
- /* U4 supports a DART bypass, we use it for 64-bit capable
- * devices to improve performances. However, that only works
- * for devices connected to U4 own PCIe interface, not bridged
- * through hypertransport. We need the device to support at
- * least 40 bits of addresses.
- */
- if (dart_device_on_pcie(dev) && dma_mask >= DMA_BIT_MASK(40)) {
- dev_info(dev, "Using 64-bit DMA iommu bypass\n");
- set_dma_ops(dev, &dma_nommu_ops);
- } else {
- dev_info(dev, "Using 32-bit DMA via iommu\n");
- set_dma_ops(dev, &dma_iommu_ops);
- }
+ if (dart_is_u4 && dart_device_on_pcie(&dev->dev))
+ set_dma_offset(&dev->dev, DART_U4_BYPASS_BASE);
+ set_iommu_table_base(&dev->dev, &iommu_table_dart);
+}