diff --git a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
index 068295b7c0..a0e7e5b6f2 100644
--- a/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
+++ b/MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
@@ -2,7 +2,7 @@
 
   PCI Root Bridge Io Protocol code.
 
-Copyright (c) 1999 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 1999 - 2017, Intel Corporation. All rights reserved.<BR>
 This program and the accompanying materials
 are licensed and made available under the terms and conditions of the BSD License
 which accompanies this distribution.  The full text of the license may be found at
@@ -1085,7 +1085,7 @@ RootBridgeIoMap (
     }
     Status = mIoMmuProtocol->Map (
                                mIoMmuProtocol,
-                               Operation,
+                               (EDKII_IOMMU_OPERATION) Operation,
                                HostAddress,
                                NumberOfBytes,
                                DeviceAddress,