UefiCpuPkg/AmdSmmCpuFeaturesLib: Skip SMBASE configuration

This patch is to avoid configure SMBASE if SmBase relocation has been done. If gSmmBaseHobGuid found, means SmBase info has been relocated and recorded in the SmBase array. No need to do the relocation in SmmCpuFeaturesInitializeProcessor(). Signed-off-by: Phil Noh <[email protected]>
coreboot · Sep 17, 2024 · b0d1cb5 · b0d1cb5
1 parent 670e263
commit b0d1cb5
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Showing 2 changed files with 28 additions and 5 deletions.
diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/AmdSmmCpuFeaturesLib.c b/UefiCpuPkg/Library/SmmCpuFeaturesLib/AmdSmmCpuFeaturesLib.c
@@ -4,17 +4,19 @@ for AMD based platforms.
 
 Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
 Copyright (c) Microsoft Corporation.<BR>
-Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.<BR>
+Copyright (C) 2023 - 2024 Advanced Micro Devices, Inc. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
+#include <Guid/SmmBaseHob.h>
 #include <Library/SmmCpuFeaturesLib.h>
 #include <Uefi/UefiBaseType.h>
 #include <Register/Amd/SmramSaveStateMap.h>
 #include <Library/BaseLib.h>
 #include <Library/DebugLib.h>
 #include <Library/MmSaveStateLib.h>
+#include <Library/HobLib.h>
 
 // EFER register LMA bit
 #define LMA  BIT10
@@ -27,6 +29,12 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 // The mode of the CPU at the time an SMI occurs
 STATIC UINT8  mSmmSaveStateRegisterLma;
 
+//
+// Indicate SmBase for each Processors has been relocated or not. If TRUE,
+// means no need to do the relocation in SmmCpuFeaturesInitializeProcessor().
+//
+BOOLEAN  mSmmCpuFeaturesSmmRelocated;
+
 /**
   Performs library initialization.
 
@@ -46,6 +54,12 @@ CpuFeaturesLibInitialization (
   if (LMAValue) {
     mSmmSaveStateRegisterLma = EFI_SMM_SAVE_STATE_REGISTER_LMA_64BIT;
   }
+
+  //
+  // If gSmmBaseHobGuid found, means SmBase info has been relocated and recorded
+  // in the SmBase array.
+  //
+  mSmmCpuFeaturesSmmRelocated = (BOOLEAN)(GetFirstGuidHob (&gSmmBaseHobGuid) != NULL);
 }
 
 /**
@@ -85,10 +99,15 @@ SmmCpuFeaturesInitializeProcessor (
   UINT32                    LMAValue;
 
   //
-  // Configure SMBASE.
+  // No need to configure SMBASE if SmBase relocation has been done.
   //
-  CpuState             = (AMD_SMRAM_SAVE_STATE_MAP *)(UINTN)(SMM_DEFAULT_SMBASE + SMRAM_SAVE_STATE_MAP_OFFSET);
-  CpuState->x64.SMBASE = (UINT32)CpuHotPlugData->SmBase[CpuIndex];
+  if (!mSmmCpuFeaturesSmmRelocated) {
+    //
+    // Configure SMBASE.
+    //
+    CpuState             = (AMD_SMRAM_SAVE_STATE_MAP *)(UINTN)(SMM_DEFAULT_SMBASE + SMRAM_SAVE_STATE_MAP_OFFSET);
+    CpuState->x64.SMBASE = (UINT32)CpuHotPlugData->SmBase[CpuIndex];
+  }
 
   // Re-initialize the value of mSmmSaveStateRegisterLma flag which might have been changed in PiCpuSmmDxeSmm Driver
   // Entry point, to make sure correct value on AMD platform is assigned to be used by SmmCpuFeaturesLib.

diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/AmdSmmCpuFeaturesLib.inf b/UefiCpuPkg/Library/SmmCpuFeaturesLib/AmdSmmCpuFeaturesLib.inf
@@ -2,7 +2,7 @@
 #  The CPU specific programming for PiSmmCpuDxeSmm module.
 #
 #  Copyright (c) 2009 - 2016, Intel Corporation. All rights reserved.<BR>
-#  Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.<BR>
+#  Copyright (C) 2023 - 2024 Advanced Micro Devices, Inc. All rights reserved.<BR>
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
 #
 ##
@@ -32,6 +32,10 @@
   MemoryAllocationLib
   DebugLib
   MmSaveStateLib
+  HobLib
+
+[Guids]
+  gSmmBaseHobGuid                ## CONSUMES
 
 [FeaturePcd]
   gUefiCpuPkgTokenSpaceGuid.PcdSmrrEnable               ## CONSUMES