1 files changed, 20 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c
index a720b54b971c..bd1a2aba599f 100644
--- a/arch/powerpc/kernel/dma-swiotlb.c
+++ b/arch/powerpc/kernel/dma-swiotlb.c
@@ -105,3 +105,23 @@ int __init swiotlb_setup_bus_notifier(void)
 			      &ppc_swiotlb_plat_bus_notifier);
 	return 0;
 }
+
+void swiotlb_detect_4g(void)
+{
+	if ((memblock_end_of_DRAM() - 1) > 0xffffffff)
+		ppc_swiotlb_enable = 1;
+}
+
+static int __init swiotlb_late_init(void)
+{
+	if (ppc_swiotlb_enable) {
+		swiotlb_print_info();
+		set_pci_dma_ops(&swiotlb_dma_ops);
+		ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_swiotlb;
+	} else {
+		swiotlb_free();
+	}
+
+	return 0;
+}
+subsys_initcall(swiotlb_late_init);