Implement MmServicesTableLib for MM Core (#730)

This change added the long vacant `MmServicesTableLib` for MM core instance.
The implementation will use extern to link the gMmst to the global MM table,
so that the libraries can use gMmst more generically.

cherry-pick from 03d53bb, d4dff6b, 1f75b27

StandaloneMmPkg/Library/StandaloneMmCoreMemoryAllocationLib/StandaloneMmCoreMemoryAllocationLib.c

@@ -15,9 +15,10 @@
 #include <Library/BaseMemoryLib.h>
 #include <Library/DebugLib.h>
 #include <Library/HobLib.h>
+#include <Library/MmServicesTableLib.h> // MU_CHANGE: Added for gMmst
 #include "StandaloneMmCoreMemoryAllocationServices.h"
 
-EFI_MM_SYSTEM_TABLE  *gMmst = NULL;
+// EFI_MM_SYSTEM_TABLE  *gMmst = NULL; // MU_CHANGE: Removed for gMmst
 
 /**
   Allocates one or more 4KB pages of a certain memory type.

StandaloneMmPkg/Library/StandaloneMmCoreMemoryAllocationLib/StandaloneMmCoreMemoryAllocationLib.inf

@@ -39,6 +39,8 @@
   BaseMemoryLib
   DebugLib
   HobLib
+  # MU_CHANGE: Added for gMmst
+  MmServicesTableLib
 
 [Guids]
   gEfiMmPeiMmramMemoryReserveGuid

StandaloneMmPkg/Library/StandaloneMmServicesTableLib/StandaloneMmServicesTableLibCore.c

@@ -0,0 +1,14 @@
+/** @file
+  MM Services Table Library.
+
+  Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiMm.h>
+#include <Library/MmServicesTableLib.h>
+#include <Library/DebugLib.h>
+
+EFI_MM_SYSTEM_TABLE  *gMmst = NULL;

StandaloneMmPkg/Library/StandaloneMmServicesTableLib/StandaloneMmServicesTableLibCore.inf

@@ -0,0 +1,28 @@
+## @file
+# Standalone MM Services Table Library.
+#
+# Copyright (c) Microsoft Corporation.
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x0001001B
+  BASE_NAME                      = StandaloneMmServicesTableLibCore
+  FILE_GUID                      = A9E61A64-FDD4-4162-9321-C6769FB96E3B
+  MODULE_TYPE                    = MM_CORE_STANDALONE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = MmServicesTableLib|MM_CORE_STANDALONE
+  PI_SPECIFICATION_VERSION       = 0x00010032
+
+#
+#  VALID_ARCHITECTURES           = IA32 X64 ARM AARCH64
+#
+
+[Sources]
+  StandaloneMmServicesTableLibCore.c
+
+[Packages]
+  MdePkg/MdePkg.dec

StandaloneMmPkg/StandaloneMmPkg.dsc

@@ -83,6 +83,8 @@
 
 [LibraryClasses.common.MM_CORE_STANDALONE]
   HobLib|StandaloneMmPkg/Library/StandaloneMmCoreHobLib/StandaloneMmCoreHobLib.inf
+  # MU_CHANGE: Added core instance of MmServicesTableLib
+  MmServicesTableLib|StandaloneMmPkg/Library/StandaloneMmServicesTableLib/StandaloneMmServicesTableLibCore.inf
 
 [LibraryClasses.common.MM_STANDALONE]
   MemoryAllocationLib|StandaloneMmPkg/Library/StandaloneMmMemoryAllocationLib/StandaloneMmMemoryAllocationLib.inf
@@ -138,6 +140,7 @@
 
 # MU_CHANGE [BEGIN]
   StandaloneMmPkg/Library/StandaloneMmCoreEntryPointNull/StandaloneMmCoreEntryPointNull.inf
+  StandaloneMmPkg/Library/StandaloneMmServicesTableLib/StandaloneMmServicesTableLibCore.inf
 
 [Components.X64]
   StandaloneMmPkg/Library/StandaloneMmCoreEntryPoint/StandaloneMmCoreEntryPoint.inf