[PATCH v4 7/7] SecurityPkg: Tcg2Acpi: Added unblock memory interface for NVS region

["Kun Qin" <kun.q@outlook.com>]

This changes added usage of MmUnblockMemoryLib to explicitly request
allocated NVS region to be accessible from MM environment. It will bring
in compatibility with architectures that supports full memory blockage
inside MM.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Qi Zhang <qi1.zhang@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>

Signed-off-by: Kun Qin <kun.q@outlook.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>
---

Notes:
    v4:
    - Previously reviewed, no change.
    
    v3:
    - Added review-by tag. [Jiewen]
    - Remove Dxe prefix to match interface update. [Jiewen]
    
    v2:
    - Newly added in v2.

 SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.c   | 6 ++++++
 SecurityPkg/SecurityPkg.dsc           | 1 +
 SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.inf | 1 +
 3 files changed, 8 insertions(+)

diff --git a/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.c b/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.c
index 9d6bc09bdc0d..db2e56b6122c 100644
--- a/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.c
+++ b/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.c
@@ -38,6 +38,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/Tpm2DeviceLib.h>
 #include <Library/Tpm2CommandLib.h>
 #include <Library/UefiLib.h>
+#include <Library/MmUnblockMemoryLib.h>
 
 //
 // Physical Presence Interface Version supported by Platform
@@ -147,6 +148,11 @@ AssignOpRegion (
       ZeroMem ((VOID *)(UINTN)MemoryAddress, Size);
       OpRegion->RegionOffset = (UINT32) (UINTN) MemoryAddress;
       OpRegion->RegionLen    = (UINT8) Size;
+      // Request to unblock this region from MM core
+      Status = MmUnblockMemoryRequest (MemoryAddress, EFI_SIZE_TO_PAGES (Size));
+      if (Status != EFI_UNSUPPORTED && EFI_ERROR (Status)) {
+        ASSERT_EFI_ERROR (Status);
+      }
       break;
     }
   }
diff --git a/SecurityPkg/SecurityPkg.dsc b/SecurityPkg/SecurityPkg.dsc
index 74ec42966273..a77665518bdd 100644
--- a/SecurityPkg/SecurityPkg.dsc
+++ b/SecurityPkg/SecurityPkg.dsc
@@ -67,6 +67,7 @@ [LibraryClasses]
   VariableKeyLib|SecurityPkg/Library/VariableKeyLibNull/VariableKeyLibNull.inf
   RpmcLib|SecurityPkg/Library/RpmcLibNull/RpmcLibNull.inf
   TcgEventLogRecordLib|SecurityPkg/Library/TcgEventLogRecordLib/TcgEventLogRecordLib.inf
+  MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
 
 [LibraryClasses.ARM]
   #
diff --git a/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.inf b/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.inf
index 42ddb4bd1f39..f1c6ae5b1cb4 100644
--- a/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.inf
+++ b/SecurityPkg/Tcg/Tcg2Acpi/Tcg2Acpi.inf
@@ -57,6 +57,7 @@ [LibraryClasses]
   Tpm2CommandLib
   Tcg2PhysicalPresenceLib
   PcdLib
+  MmUnblockMemoryLib
 
 [Guids]
   gEfiTpmDeviceInstanceTpm20DtpmGuid                            ## PRODUCES           ## GUID       # TPM device identifier
-- 
2.30.0.windows.1