diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.inf
index a95e1e730c2c..66ac77850915 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.inf
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.inf
@@ -32,6 +32,7 @@ [Defines]
 #
 
 [Sources]
+  QemuFwCfgLibInternal.h
   QemuFwCfgLib.c
   QemuFwCfgPeiDxe.c
 
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf
index 03a659c9b082..c1d6a54b1a39 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf
@@ -30,6 +30,7 @@ [Defines]
 #
 
 [Sources]
+  QemuFwCfgLibInternal.h
   QemuFwCfgLib.c
   QemuFwCfgSec.c
 
diff --git a/OvmfPkg/Include/Library/QemuFwCfgLib.h b/OvmfPkg/Include/Library/QemuFwCfgLib.h
index baaa257d6188..7c29422fbd72 100644
--- a/OvmfPkg/Include/Library/QemuFwCfgLib.h
+++ b/OvmfPkg/Include/Library/QemuFwCfgLib.h
@@ -206,22 +206,6 @@ QemuFwCfgFindFile (
 
 
 /**
-  Returns a boolean indicating if the firmware configuration interface is
-  available for library-internal purposes.
-
-  This function never changes fw_cfg state.
-
-  @retval    TRUE   The interface is available internally.
-  @retval    FALSE  The interface is not available internally.
-**/
-BOOLEAN
-EFIAPI
-InternalQemuFwCfgIsAvailable (
-  VOID
-  );
-
-
-/**
   Determine if S3 support is explicitly enabled.
 
   @retval  TRUE   if S3 support is explicitly enabled.
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibInternal.h b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibInternal.h
new file mode 100644
index 000000000000..5b162bf98739
--- /dev/null
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibInternal.h
@@ -0,0 +1,33 @@
+/** @file
+  Internal interfaces specific to the QemuFwCfgLib instances in OvmfPkg.
+
+  Copyright (C) 2016, Red Hat, Inc.
+
+  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
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef __QEMU_FW_CFG_LIB_INTERNAL_H__
+#define __QEMU_FW_CFG_LIB_INTERNAL_H__
+
+/**
+  Returns a boolean indicating if the firmware configuration interface is
+  available for library-internal purposes.
+
+  This function never changes fw_cfg state.
+
+  @retval    TRUE   The interface is available internally.
+  @retval    FALSE  The interface is not available internally.
+**/
+BOOLEAN
+InternalQemuFwCfgIsAvailable (
+  VOID
+  );
+
+#endif
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
index 5c96d2af2532..804d5b0e42be 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLib.c
@@ -22,6 +22,8 @@
 #include <Library/MemoryAllocationLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 
+#include "QemuFwCfgLibInternal.h"
+
 
 /**
   Reads an 8-bit I/O port fifo into a block of memory.
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiDxe.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiDxe.c
index f693cff29e01..88d88c0edf69 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiDxe.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiDxe.c
@@ -17,6 +17,8 @@
 #include <Library/DebugLib.h>
 #include <Library/QemuFwCfgLib.h>
 
+#include "QemuFwCfgLibInternal.h"
+
 STATIC BOOLEAN mQemuFwCfgSupported = FALSE;
 
 
@@ -83,7 +85,6 @@ QemuFwCfgInitialize (
   @retval    FALSE  The interface is not available internally.
 **/
 BOOLEAN
-EFIAPI
 InternalQemuFwCfgIsAvailable (
   VOID
   )
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSec.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSec.c
index 88c32ce89a72..56c59ca3f01d 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSec.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSec.c
@@ -19,6 +19,7 @@
 #include <Library/DebugLib.h>
 #include <Library/QemuFwCfgLib.h>
 
+#include "QemuFwCfgLibInternal.h"
 
 /**
   Returns a boolean indicating if the firmware configuration interface
@@ -67,7 +68,6 @@ QemuFwCfgIsAvailable (
   @retval    FALSE  The interface is not available internally.
 **/
 BOOLEAN
-EFIAPI
 InternalQemuFwCfgIsAvailable (
   VOID
   )
