1 files changed, 39 insertions, 0 deletions
diff --git a/EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseLib/X64/WriteMsr64.asm b/EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseLib/X64/WriteMsr64.asm
new file mode 100644
index 0000000000..95c48f46dc
--- /dev/null
+++ b/EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseLib/X64/WriteMsr64.asm
@@ -0,0 +1,39 @@
+; Copyright (c) 2004, Intel Corporation                                                         
+; All rights reserved. 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.    
+;
+; Module Name:
+;
+;   WriteMsr64.Asm
+;
+; Abstract:
+;
+;   AsmWriteMsr64 function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+    .code
+
+;------------------------------------------------------------------------------
+; UINT64
+; EFIAPI
+; AsmWriteMsr64 (
+;   IN UINT32  Index,
+;   IN UINT64  Value
+;   );
+;------------------------------------------------------------------------------
+AsmWriteMsr64   PROC
+    mov     rax, rdx                    ; meanwhile, rax <- return value
+    shr     rdx, 20h                    ; edx:eax contains the value to write
+    wrmsr
+    ret
+AsmWriteMsr64   ENDP
+
+    END