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diff --git a/MdePkg/Include/Protocol/MmCommunication.h b/MdePkg/Include/Protocol/MmCommunication.h
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+++ b/MdePkg/Include/Protocol/MmCommunication.h
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+/** @file
+  EFI MM Communication Protocol as defined in the PI 1.5 specification.
+
+  This protocol provides a means of communicating between drivers outside of MM and MMI
+  handlers inside of MM.
+
+  Copyright (c) 2017, 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.
+
+**/
+
+#ifndef _MM_COMMUNICATION_H_
+#define _MM_COMMUNICATION_H_
+
+#pragma pack(1)
+
+///
+/// To avoid confusion in interpreting frames, the communication buffer should always
+/// begin with EFI_MM_COMMUNICATE_HEADER
+///
+typedef struct {
+  ///
+  /// Allows for disambiguation of the message format.
+  ///
+  EFI_GUID  HeaderGuid;
+  ///
+  /// Describes the size of Data (in bytes) and does not include the size of the header.
+  ///
+  UINTN     MessageLength;
+  ///
+  /// Designates an array of bytes that is MessageLength in size.
+  ///
+  UINT8     Data[1];
+} EFI_MM_COMMUNICATE_HEADER;
+
+#pragma pack()
+
+#define EFI_MM_COMMUNICATION_PROTOCOL_GUID \
+  { \
+    0xc68ed8e2, 0x9dc6, 0x4cbd, { 0x9d, 0x94, 0xdb, 0x65, 0xac, 0xc5, 0xc3, 0x32 } \
+  }
+
+typedef struct _EFI_MM_COMMUNICATION_PROTOCOL  EFI_MM_COMMUNICATION_PROTOCOL;
+
+/**
+  Communicates with a registered handler.
+
+  This function provides a service to send and receive messages from a registered UEFI service.
+
+  @param[in] This                The EFI_MM_COMMUNICATION_PROTOCOL instance.
+  @param[in] CommBuffer          A pointer to the buffer to convey into MMRAM.
+  @param[in] CommSize            The size of the data buffer being passed in.On exit, the size of data
+                                 being returned. Zero if the handler does not wish to reply with any data.
+
+  @retval EFI_SUCCESS            The message was successfully posted.
+  @retval EFI_INVALID_PARAMETER  The CommBuffer was NULL.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_MM_COMMUNICATE)(
+  IN CONST EFI_MM_COMMUNICATION_PROTOCOL   *This,
+  IN OUT VOID                              *CommBuffer,
+  IN OUT UINTN                             *CommSize
+  );
+
+///
+/// EFI MM Communication Protocol provides runtime services for communicating
+/// between DXE drivers and a registered MMI handler.
+///
+struct _EFI_MM_COMMUNICATION_PROTOCOL {
+  EFI_MM_COMMUNICATE  Communicate;
+};
+
+extern EFI_GUID gEfiMmCommunicationProtocolGuid;
+
+#endif
+