diff --git a/MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsicSev.inf b/MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsicSev.inf
index a74e54bee8..7fe1c60f04 100644
--- a/MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsicSev.inf
+++ b/MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsicSev.inf
@@ -31,6 +31,7 @@
   BaseIoLibIntrinsicInternal.h
   IoHighLevel.c
   IoLibTdx.h
+  IoLibSev.h
 
 [Sources.IA32]
   IoLibGcc.c    | GCC
@@ -44,6 +45,7 @@
   IoLibMsc.c    | MSFT
   IoLib.c
   IoLibInternalTdx.c
+  IoLibFifo.c
   X64/IoFifoSev.nasm
 
 [Packages]
diff --git a/MdePkg/Library/BaseIoLibIntrinsic/IoLibFifo.c b/MdePkg/Library/BaseIoLibIntrinsic/IoLibFifo.c
new file mode 100644
index 0000000000..9a94bc6a05
--- /dev/null
+++ b/MdePkg/Library/BaseIoLibIntrinsic/IoLibFifo.c
@@ -0,0 +1,217 @@
+/** @file
+  IoFifo read/write routines.
+
+  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "BaseIoLibIntrinsicInternal.h"
+#include "IoLibSev.h"
+#include "IoLibTdx.h"
+#include <Uefi/UefiBaseType.h>
+#include <Library/TdxLib.h>
+
+/**
+  Reads an 8-bit I/O port fifo into a block of memory.
+
+  Reads the 8-bit I/O fifo port specified by Port.
+  The port is read Count times, and the read data is
+  stored in the provided Buffer.
+
+  This function must guarantee that all I/O read and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  In TDX a serial of TdIoRead8 is invoked to read the I/O port fifo.
+
+  @param  Port    The I/O port to read.
+  @param  Count   The number of times to read I/O port.
+  @param  Buffer  The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+IoReadFifo8 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  OUT     VOID   *Buffer
+  )
+{
+  if (IsTdxGuest ()) {
+    TdIoReadFifo8 (Port, Count, Buffer);
+  } else {
+    SevIoReadFifo8 (Port, Count, Buffer);
+  }
+}
+
+/**
+  Writes a block of memory into an 8-bit I/O port fifo.
+
+  Writes the 8-bit I/O fifo port specified by Port.
+  The port is written Count times, and the write data is
+  retrieved from the provided Buffer.
+
+  This function must guarantee that all I/O write and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  In TDX a serial of TdIoWrite8 is invoked to write data to the I/O port.
+
+  @param  Port    The I/O port to write.
+  @param  Count   The number of times to write I/O port.
+  @param  Buffer  The buffer to retrieve the write data from.
+
+**/
+VOID
+EFIAPI
+IoWriteFifo8 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  IN      VOID   *Buffer
+  )
+{
+  if (IsTdxGuest ()) {
+    TdIoWriteFifo8 (Port, Count, Buffer);
+  } else {
+    SevIoWriteFifo8 (Port, Count, Buffer);
+  }
+}
+
+/**
+  Reads a 16-bit I/O port fifo into a block of memory.
+
+  Reads the 16-bit I/O fifo port specified by Port.
+  The port is read Count times, and the read data is
+  stored in the provided Buffer.
+
+  This function must guarantee that all I/O read and write operations are
+  serialized.
+
+  If 16-bit I/O port operations are not supported, then ASSERT().
+
+  In TDX a serial of TdIoRead16 is invoked to read data from the I/O port.
+
+  @param  Port    The I/O port to read.
+  @param  Count   The number of times to read I/O port.
+  @param  Buffer  The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+IoReadFifo16 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  OUT     VOID   *Buffer
+  )
+{
+  if (IsTdxGuest ()) {
+    TdIoReadFifo16 (Port, Count, Buffer);
+  } else {
+    SevIoReadFifo16 (Port, Count, Buffer);
+  }
+}
+
+/**
+  Writes a block of memory into a 16-bit I/O port fifo.
+
+  Writes the 16-bit I/O fifo port specified by Port.
+  The port is written Count times, and the write data is
+  retrieved from the provided Buffer.
+
+  This function must guarantee that all I/O write and write operations are
+  serialized.
+
+  If 16-bit I/O port operations are not supported, then ASSERT().
+
+  In TDX a serial of TdIoWrite16 is invoked to write data to the I/O port.
+
+  @param  Port    The I/O port to write.
+  @param  Count   The number of times to write I/O port.
+  @param  Buffer  The buffer to retrieve the write data from.
+
+**/
+VOID
+EFIAPI
+IoWriteFifo16 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  IN      VOID   *Buffer
+  )
+{
+  if (IsTdxGuest ()) {
+    TdIoWriteFifo16 (Port, Count, Buffer);
+  } else {
+    SevIoWriteFifo16 (Port, Count, Buffer);
+  }
+}
+
+/**
+  Reads a 32-bit I/O port fifo into a block of memory.
+
+  Reads the 32-bit I/O fifo port specified by Port.
+  The port is read Count times, and the read data is
+  stored in the provided Buffer.
+
+  This function must guarantee that all I/O read and write operations are
+  serialized.
+
+  If 32-bit I/O port operations are not supported, then ASSERT().
+
+  In TDX a serial of TdIoRead32 is invoked to read data from the I/O port.
+
+  @param  Port    The I/O port to read.
+  @param  Count   The number of times to read I/O port.
+  @param  Buffer  The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+IoReadFifo32 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  OUT     VOID   *Buffer
+  )
+{
+  if (IsTdxGuest ()) {
+    TdIoReadFifo32 (Port, Count, Buffer);
+  } else {
+    SevIoReadFifo32 (Port, Count, Buffer);
+  }
+}
+
+/**
+  Writes a block of memory into a 32-bit I/O port fifo.
+
+  Writes the 32-bit I/O fifo port specified by Port.
+  The port is written Count times, and the write data is
+  retrieved from the provided Buffer.
+
+  This function must guarantee that all I/O write and write operations are
+  serialized.
+
+  If 32-bit I/O port operations are not supported, then ASSERT().
+
+  In TDX a serial of TdIoWrite32 is invoked to write data to the I/O port.
+
+  @param  Port    The I/O port to write.
+  @param  Count   The number of times to write I/O port.
+  @param  Buffer  The buffer to retrieve the write data from.
+
+**/
+VOID
+EFIAPI
+IoWriteFifo32 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  IN      VOID   *Buffer
+  )
+{
+  if (IsTdxGuest ()) {
+    TdIoWriteFifo32 (Port, Count, Buffer);
+  } else {
+    SevIoWriteFifo32 (Port, Count, Buffer);
+  }
+}
diff --git a/MdePkg/Library/BaseIoLibIntrinsic/IoLibSev.h b/MdePkg/Library/BaseIoLibIntrinsic/IoLibSev.h
new file mode 100644
index 0000000000..6d7cafcff2
--- /dev/null
+++ b/MdePkg/Library/BaseIoLibIntrinsic/IoLibSev.h
@@ -0,0 +1,166 @@
+/** @file
+  Header file for SEV IO library.
+
+  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
+   SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef IOLIB_SEV_H_
+#define IOLIB_SEV_H_
+
+#include <Base.h>
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+/**
+  Reads an 8-bit I/O port fifo into a block of memory.
+
+  Reads the 8-bit I/O fifo port specified by Port.
+  The port is read Count times, and the read data is
+  stored in the provided Buffer.
+
+  This function must guarantee that all I/O read and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  @param  Port    The I/O port to read.
+  @param  Count   The number of times to read I/O port.
+  @param  Buffer  The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+SevIoReadFifo8 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  OUT     VOID   *Buffer
+  );
+
+/**
+  Writes a block of memory into an 8-bit I/O port fifo.
+
+  Writes the 8-bit I/O fifo port specified by Port.
+  The port is written Count times, and the write data is
+  retrieved from the provided Buffer.
+
+  This function must guarantee that all I/O write and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  @param  Port    The I/O port to write.
+  @param  Count   The number of times to write I/O port.
+  @param  Buffer  The buffer to retrieve the write data from.
+
+**/
+VOID
+EFIAPI
+SevIoWriteFifo8 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  IN      VOID   *Buffer
+  );
+
+/**
+  Reads an 8-bit I/O port fifo into a block of memory.
+
+  Reads the 8-bit I/O fifo port specified by Port.
+  The port is read Count times, and the read data is
+  stored in the provided Buffer.
+
+  This function must guarantee that all I/O read and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  @param  Port    The I/O port to read.
+  @param  Count   The number of times to read I/O port.
+  @param  Buffer  The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+SevIoReadFifo16 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  OUT     VOID   *Buffer
+  );
+
+/**
+  Writes a block of memory into an 8-bit I/O port fifo.
+
+  Writes the 8-bit I/O fifo port specified by Port.
+  The port is written Count times, and the write data is
+  retrieved from the provided Buffer.
+
+  This function must guarantee that all I/O write and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  @param  Port    The I/O port to write.
+  @param  Count   The number of times to write I/O port.
+  @param  Buffer  The buffer to retrieve the write data from.
+
+**/
+VOID
+EFIAPI
+SevIoWriteFifo16 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  IN      VOID   *Buffer
+  );
+
+/**
+  Reads an 8-bit I/O port fifo into a block of memory.
+
+  Reads the 8-bit I/O fifo port specified by Port.
+  The port is read Count times, and the read data is
+  stored in the provided Buffer.
+
+  This function must guarantee that all I/O read and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  @param  Port    The I/O port to read.
+  @param  Count   The number of times to read I/O port.
+  @param  Buffer  The buffer to store the read data into.
+
+**/
+VOID
+EFIAPI
+SevIoReadFifo32 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  OUT     VOID   *Buffer
+  );
+
+/**
+  Writes a block of memory into an 8-bit I/O port fifo.
+
+  Writes the 8-bit I/O fifo port specified by Port.
+  The port is written Count times, and the write data is
+  retrieved from the provided Buffer.
+
+  This function must guarantee that all I/O write and write operations are
+  serialized.
+
+  If 8-bit I/O port operations are not supported, then ASSERT().
+
+  @param  Port    The I/O port to write.
+  @param  Count   The number of times to write I/O port.
+  @param  Buffer  The buffer to retrieve the write data from.
+
+**/
+VOID
+EFIAPI
+SevIoWriteFifo32 (
+  IN      UINTN  Port,
+  IN      UINTN  Count,
+  IN      VOID   *Buffer
+  );
+
+#endif
diff --git a/MdePkg/Library/BaseIoLibIntrinsic/X64/IoFifoSev.nasm b/MdePkg/Library/BaseIoLibIntrinsic/X64/IoFifoSev.nasm
index 106f8881c5..d02286b4d5 100644
--- a/MdePkg/Library/BaseIoLibIntrinsic/X64/IoFifoSev.nasm
+++ b/MdePkg/Library/BaseIoLibIntrinsic/X64/IoFifoSev.nasm
@@ -67,14 +67,14 @@ ASM_PFX(SevNoRepIo):
 ;------------------------------------------------------------------------------
 ;  VOID
 ;  EFIAPI
-;  IoReadFifo8 (
+;  SevIoReadFifo8 (
 ;    IN  UINTN                 Port,              // rcx
 ;    IN  UINTN                 Size,              // rdx
 ;    OUT VOID                  *Buffer            // r8
 ;    );
 ;------------------------------------------------------------------------------
-global ASM_PFX(IoReadFifo8)
-ASM_PFX(IoReadFifo8):
+global ASM_PFX(SevIoReadFifo8)
+ASM_PFX(SevIoReadFifo8):
     xchg    rcx, rdx
     xchg    rdi, r8             ; rdi: buffer address; r8: save rdi
 
@@ -103,14 +103,14 @@ ASM_PFX(IoReadFifo8):
 ;------------------------------------------------------------------------------
 ;  VOID
 ;  EFIAPI
-;  IoReadFifo16 (
+;  SevIoReadFifo16 (
 ;    IN  UINTN                 Port,              // rcx
 ;    IN  UINTN                 Size,              // rdx
 ;    OUT VOID                  *Buffer            // r8
 ;    );
 ;------------------------------------------------------------------------------
-global ASM_PFX(IoReadFifo16)
-ASM_PFX(IoReadFifo16):
+global ASM_PFX(SevIoReadFifo16)
+ASM_PFX(SevIoReadFifo16):
     xchg    rcx, rdx
     xchg    rdi, r8             ; rdi: buffer address; r8: save rdi
 
@@ -139,14 +139,14 @@ ASM_PFX(IoReadFifo16):
 ;------------------------------------------------------------------------------
 ;  VOID
 ;  EFIAPI
-;  IoReadFifo32 (
+;  SevIoReadFifo32 (
 ;    IN  UINTN                 Port,              // rcx
 ;    IN  UINTN                 Size,              // rdx
 ;    OUT VOID                  *Buffer            // r8
 ;    );
 ;------------------------------------------------------------------------------
-global ASM_PFX(IoReadFifo32)
-ASM_PFX(IoReadFifo32):
+global ASM_PFX(SevIoReadFifo32)
+ASM_PFX(SevIoReadFifo32):
     xchg    rcx, rdx
     xchg    rdi, r8             ; rdi: buffer address; r8: save rdi
 
@@ -181,8 +181,8 @@ ASM_PFX(IoReadFifo32):
 ;    IN VOID                   *Buffer            // r8
 ;    );
 ;------------------------------------------------------------------------------
-global ASM_PFX(IoWriteFifo8)
-ASM_PFX(IoWriteFifo8):
+global ASM_PFX(SevIoWriteFifo8)
+ASM_PFX(SevIoWriteFifo8):
     xchg    rcx, rdx
     xchg    rsi, r8             ; rsi: buffer address; r8: save rsi
 
@@ -211,14 +211,14 @@ ASM_PFX(IoWriteFifo8):
 ;------------------------------------------------------------------------------
 ;  VOID
 ;  EFIAPI
-;  IoWriteFifo16 (
+;  SevIoWriteFifo16 (
 ;    IN UINTN                  Port,              // rcx
 ;    IN UINTN                  Size,              // rdx
 ;    IN VOID                   *Buffer            // r8
 ;    );
 ;------------------------------------------------------------------------------
-global ASM_PFX(IoWriteFifo16)
-ASM_PFX(IoWriteFifo16):
+global ASM_PFX(SevIoWriteFifo16)
+ASM_PFX(SevIoWriteFifo16):
     xchg    rcx, rdx
     xchg    rsi, r8             ; rsi: buffer address; r8: save rsi
 
@@ -247,14 +247,14 @@ ASM_PFX(IoWriteFifo16):
 ;------------------------------------------------------------------------------
 ;  VOID
 ;  EFIAPI
-;  IoWriteFifo32 (
+;  SevIoWriteFifo32 (
 ;    IN UINTN                  Port,              // rcx
 ;    IN UINTN                  Size,              // rdx
 ;    IN VOID                   *Buffer            // r8
 ;    );
 ;------------------------------------------------------------------------------
-global ASM_PFX(IoWriteFifo32)
-ASM_PFX(IoWriteFifo32):
+global ASM_PFX(SevIoWriteFifo32)
+ASM_PFX(SevIoWriteFifo32):
     xchg    rcx, rdx
     xchg    rsi, r8             ; rsi: buffer address; r8: save rsi