1 files changed, 36 insertions, 0 deletions
diff --git a/OvmfPkg/Library/QemuFwCfgLib/X64/IoLibExAsm.asm b/OvmfPkg/Library/QemuFwCfgLib/X64/IoLibExAsm.asm
new file mode 100644
index 0000000000..c60ad2c5d4
--- /dev/null
+++ b/OvmfPkg/Library/QemuFwCfgLib/X64/IoLibExAsm.asm
@@ -0,0 +1,36 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006 - 2012, 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.
+;
+;------------------------------------------------------------------------------
+
+    .code
+
+;------------------------------------------------------------------------------
+;  VOID
+;  EFIAPI
+;  IoReadFifo8 (
+;    IN UINTN                  Port,              // rcx
+;    IN UINTN                  Size,              // rdx
+;    IN VOID                   *Buffer            // r8
+;    );
+;------------------------------------------------------------------------------
+IoReadFifo8 PROC
+
+    xchg    rcx, rdx
+    xchg    rdi, r8             ; rdi: buffer address; r8: save rdi
+rep insb
+    mov     rdi, r8             ; restore rdi
+    ret
+
+IoReadFifo8 ENDP
+
+    END
+