diff --git a/OvmfPkg/Sec/SecMain.inf b/OvmfPkg/Sec/SecMain.inf
index 66ab83353e..fce99fb74c 100644
--- a/OvmfPkg/Sec/SecMain.inf
+++ b/OvmfPkg/Sec/SecMain.inf
@@ -34,9 +34,7 @@
   Ia32/SecEntry.nasm
 
 [Sources.X64]
-  X64/SecEntry.asm  | MSFT
-  X64/SecEntry.asm  | INTEL
-  X64/SecEntry.S    | GCC
+  X64/SecEntry.nasm
 
 [Packages]
   MdePkg/MdePkg.dec
diff --git a/OvmfPkg/Sec/X64/SecEntry.S b/OvmfPkg/Sec/X64/SecEntry.S
deleted file mode 100644
index 37354d9f3c..0000000000
--- a/OvmfPkg/Sec/X64/SecEntry.S
+++ /dev/null
@@ -1,56 +0,0 @@
-#      TITLE   SecEntry.asm
-#------------------------------------------------------------------------------
-#*
-#*   Copyright (c) 2006 - 2013, 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
-#*   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.
-#*
-#*    CpuAsm.asm
-#*
-#*   Abstract:
-#*
-#------------------------------------------------------------------------------
-
-
-#include <Base.h>
-
-#EXTERN ASM_PFX(SecCoreStartupWithStack)
-
-#
-# SecCore Entry Point
-#
-# Processor is in flat protected mode
-#
-# @param[in]  RAX   Initial value of the EAX register (BIST: Built-in Self Test)
-# @param[in]  DI    'BP': boot-strap processor, or 'AP': application processor
-# @param[in]  RBP   Pointer to the start of the Boot Firmware Volume
-#
-# @return     None  This routine does not return
-#
-ASM_GLOBAL ASM_PFX(_ModuleEntryPoint)
-ASM_PFX(_ModuleEntryPoint):
-
-    #
-    # Load temporary stack top at very low memory.  The C code
-    # can reload to a better address.
-    #
-    .set    SEC_TOP_OF_STACK, FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) + \
-                              FixedPcdGet32 (PcdOvmfSecPeiTempRamSize)
-    movq    $SEC_TOP_OF_STACK, %rsp 
-    nop
-
-    #
-    # Setup parameters and call SecCoreStartupWithStack
-    #   rcx: BootFirmwareVolumePtr
-    #   rdx: TopOfCurrentStack
-    #
-    movq    %rbp, %rcx
-    movq    %rsp, %rdx
-    subq    $0x20, %rsp
-    call    ASM_PFX(SecCoreStartupWithStack)
-
diff --git a/OvmfPkg/Sec/X64/SecEntry.asm b/OvmfPkg/Sec/X64/SecEntry.nasm
similarity index 81%
rename from OvmfPkg/Sec/X64/SecEntry.asm
rename to OvmfPkg/Sec/X64/SecEntry.nasm
index 4135208a3a..f40427aa8e 100644
--- a/OvmfPkg/Sec/X64/SecEntry.asm
+++ b/OvmfPkg/Sec/X64/SecEntry.nasm
@@ -1,4 +1,3 @@
-      TITLE   SecEntry.asm
 ;------------------------------------------------------------------------------
 ;*
 ;*   Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR>
@@ -18,9 +17,10 @@
 
 #include <Base.h>
 
-.code
+DEFAULT REL
+SECTION .text
 
-EXTERN SecCoreStartupWithStack:PROC
+extern ASM_PFX(SecCoreStartupWithStack)
 
 ;
 ; SecCore Entry Point
@@ -33,12 +33,13 @@ EXTERN SecCoreStartupWithStack:PROC
 ;
 ; @return     None  This routine does not return
 ;
-_ModuleEntryPoint PROC PUBLIC
+global ASM_PFX(_ModuleEntryPoint)
+ASM_PFX(_ModuleEntryPoint):
 
     ;
     ; Load temporary RAM stack based on PCDs
     ;
-    SEC_TOP_OF_STACK EQU (FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) + \
+    %define SEC_TOP_OF_STACK (FixedPcdGet32 (PcdOvmfSecPeiTempRamBase) + \
                           FixedPcdGet32 (PcdOvmfSecPeiTempRamSize))
     mov     rsp, SEC_TOP_OF_STACK
     nop
@@ -50,9 +51,6 @@ _ModuleEntryPoint PROC PUBLIC
     ;
     mov     rcx, rbp
     mov     rdx, rsp
-    sub     rsp, 20h
-    call    SecCoreStartupWithStack
+    sub     rsp, 0x20
+    call    ASM_PFX(SecCoreStartupWithStack)
 
-_ModuleEntryPoint ENDP
-
-END