diff --git a/arch/powerpc/kernel/vio.c b/arch/powerpc/kernel/vio.c
index b265405..1b695fd 100644
--- a/arch/powerpc/kernel/vio.c
+++ b/arch/powerpc/kernel/vio.c
@@ -1257,6 +1257,10 @@ struct vio_dev *vio_register_device_node(struct device_node *of_node)
        viodev->dev.parent = &vio_bus_device.dev;
        viodev->dev.bus = &vio_bus_type;
        viodev->dev.release = vio_dev_release;
+        /* needed to ensure proper operation of coherent allocations
+         * later, in case driver doesn't set it explicitly */
+        dma_set_mask(&viodev->dev, DMA_BIT_MASK(64));
+        dma_set_coherent_mask(&viodev->dev, DMA_BIT_MASK(64));

        /* register with generic device framework */
        if (device_register(&viodev->dev)) {