[PATCH v1 1/3] MdePkg: MmCommunication: Added definition of MM Communication PPI

["Kun Qin" <kuqin12@gmail.com>]

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3629

MM Communication PPI was defined in PI Specification since v1.5. This
change added definition of such PPI and related GUIDs into MdePkg.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>

Signed-off-by: Kun Qin <kuqin12@gmail.com>
---
 MdePkg/Include/Ppi/MmCommunication.h | 72 ++++++++++++++++++++
 MdePkg/MdePkg.dec                    |  3 +
 2 files changed, 75 insertions(+)

diff --git a/MdePkg/Include/Ppi/MmCommunication.h b/MdePkg/Include/Ppi/MmCommunication.h
new file mode 100644
index 000000000000..7e06da2ec088
--- /dev/null
+++ b/MdePkg/Include/Ppi/MmCommunication.h
@@ -0,0 +1,72 @@
+/** @file
+  EFI MM Communication PPI definition.
+
+  This PPI provides a means of communicating between drivers outside
+  of MM and MMI handlers inside of MM in PEI phase.
+
+  Copyright (c) 2010 - 2018, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) Microsoft Corporation.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+
+#ifndef MM_COMMUNICATION_PPI_H_
+#define MM_COMMUNICATION_PPI_H_
+
+#define EFI_PEI_MM_COMMUNICATION_PPI_GUID \
+  { \
+    0xae933e1c, 0xcc47, 0x4e38, { 0x8f, 0xe, 0xe2, 0xf6, 0x1d, 0x26, 0x5, 0xdf } \
+  }
+
+typedef struct _EFI_PEI_MM_COMMUNICATION_PPI  EFI_PEI_MM_COMMUNICATION_PPI;
+
+/**
+  Communicates with a registered handler.
+
+  This function provides a service to send and receive messages from a registered PEI service.
+  The EFI_PEI_MM_COMMUNICATION_PPI driver is responsible for doing any of the copies such that
+  the data lives in PEI-service-accessible RAM.
+
+  A given implementation of the EFI_PEI_MM_COMMUNICATION_PPI may choose to use the
+  EFI_MM_CONTROL_PPI for effecting the mode transition, or it may use some other method.
+
+  The agent invoking the communication interface must be physical/virtually 1:1 mapped.
+
+  To avoid confusion in interpreting frames, the CommBuffer parameter should always begin with
+  EFI_MM_COMMUNICATE_HEADER. The header data is mandatory for messages sent into the MM agent.
+
+  Once inside of MM, the MM infrastructure will call all registered handlers with the same
+  HandlerType as the GUID specified by HeaderGuid and the CommBuffer pointing to Data.
+
+  This function is not reentrant.
+
+  @param[in] This                 The EFI_PEI_MM_COMMUNICATION_PPI instance.
+  @param[in] CommBuffer           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 buffer was NULL.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MM_COMMUNICATE)(
+  IN CONST EFI_PEI_MM_COMMUNICATION_PPI     *This,
+  IN OUT VOID                               *CommBuffer,
+  IN OUT UINTN                              *CommSize
+  );
+
+///
+/// EFI MM Communication PPI provides services for communicating between PEIM and a registered
+/// MMI handler.
+///
+struct _EFI_PEI_MM_COMMUNICATION_PPI {
+  EFI_PEI_MM_COMMUNICATE  Communicate;
+};
+
+extern EFI_GUID gEfiPeiMmCommunicationPpiGuid;
+
+#endif
diff --git a/MdePkg/MdePkg.dec b/MdePkg/MdePkg.dec
index a28a2daaffa8..9cdc915ebae9 100644
--- a/MdePkg/MdePkg.dec
+++ b/MdePkg/MdePkg.dec
@@ -991,6 +991,9 @@ [Ppis]
   ## Include/Ppi/MmConfiguration.h
   gEfiPeiMmConfigurationPpi       =  { 0xc109319, 0xc149, 0x450e, { 0xa3, 0xe3, 0xb9, 0xba, 0xdd, 0x9d, 0xc3, 0xa4 } }
 
+  ## Include/Ppi/MmCommunication.h
+  gEfiPeiMmCommunicationPpiGuid   =  { 0xae933e1c, 0xcc47, 0x4e38, { 0x8f, 0xe, 0xe2, 0xf6, 0x1d, 0x26, 0x5, 0xdf } }
+
   #
   # PPIs defined in PI 1.7.
   #
-- 
2.32.0.windows.1