From 91853ca6a5497c1b6e8ff356b6fffd977f7f5b38 Mon Sep 17 00:00:00 2001
From: Wei6 Xu <wei6.xu@intel.com>
Date: Mon, 2 Sep 2024 10:06:18 +0800
Subject: [PATCH] MdeModulePkg/VariableStandaloneMm: Notify variable write
 ready in MM

In Standalone MM, there is no notification to MM drivers that variable
write is ready. Install gSmmVariableWriteGuid into MM handle database
for the notification.

Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Ray Ni <ray.ni@intel.com>
Signed-off-by: Wei6 Xu <wei6.xu@intel.com>
---
 .../Variable/RuntimeDxe/VariableStandaloneMm.c      | 13 +++++++++++++
 .../Variable/RuntimeDxe/VariableStandaloneMm.inf    |  1 +
 2 files changed, 14 insertions(+)

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c
index f3daca3eba..10578226c6 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c
@@ -7,6 +7,8 @@ Copyright (c) 2018, Linaro, Ltd. All rights reserved. <BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
+
+#include <Library/MmServicesTableLib.h>
 #include <Library/StandaloneMmMemLib.h>
 #include "Variable.h"
 
@@ -67,6 +69,17 @@ VariableNotifySmmWriteReady (
   VOID
   )
 {
+  EFI_STATUS  Status;
+  EFI_HANDLE  Handle;
+
+  Handle = NULL;
+  Status = gMmst->MmInstallProtocolInterface (
+                    &Handle,
+                    &gSmmVariableWriteGuid,
+                    EFI_NATIVE_INTERFACE,
+                    NULL
+                    );
+  ASSERT_EFI_ERROR (Status);
 }
 
 /**
diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
index c4185718aa..2d651c3c3d 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.inf
@@ -115,6 +115,7 @@
   gEfiMemoryOverwriteControlDataGuid            ## SOMETIMES_CONSUMES   ## Variable:L"MemoryOverwriteRequestControl"
   gEfiMemoryOverwriteRequestControlLockGuid     ## SOMETIMES_PRODUCES   ## Variable:L"MemoryOverwriteRequestControlLock"
 
+  gSmmVariableWriteGuid                         ## PRODUCES             ## GUID # Install protocol
   gEfiSystemNvDataFvGuid                        ## CONSUMES             ## GUID
   gEdkiiFaultTolerantWriteGuid                  ## SOMETIMES_CONSUMES   ## HOB