diff --git a/UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveState.c b/UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveState.c
new file mode 100644
index 0000000000..9fed52896f
--- /dev/null
+++ b/UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveState.c
@@ -0,0 +1,309 @@
+/** @file
+Provides services to access SMRAM Save State Map
+
+Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.
+Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "MmSaveState.h"
+#include
+#include
+
+// EFER register LMA bit
+#define LMA BIT10
+#define EFER_ADDRESS 0xC0000080ul
+#define AMD_MM_SAVE_STATE_REGISTER_SMMREVID_INDEX 1
+#define AMD_MM_SAVE_STATE_REGISTER_MAX_INDEX 2
+
+// Macro used to simplify the lookup table entries of type CPU_MM_SAVE_STATE_LOOKUP_ENTRY
+#define MM_CPU_OFFSET(Field) OFFSET_OF (AMD_SMRAM_SAVE_STATE_MAP, Field)
+
+// Lookup table used to retrieve the widths and offsets associated with each
+// supported EFI_MM_SAVE_STATE_REGISTER value
+CONST CPU_MM_SAVE_STATE_LOOKUP_ENTRY mCpuWidthOffset[] = {
+ { 0, 0, 0, 0, FALSE }, // Reserved
+
+ //
+ // Internally defined CPU Save State Registers. Not defined in PI SMM CPU Protocol.
+ //
+ { 4, 4, MM_CPU_OFFSET (x86.SMMRevId), MM_CPU_OFFSET (x64.SMMRevId), 0, FALSE}, // AMD_MM_SAVE_STATE_REGISTER_SMMREVID_INDEX = 1
+
+ //
+ // CPU Save State registers defined in PI SMM CPU Protocol.
+ //
+ { 4, 8, MM_CPU_OFFSET (x86.GDTBase), MM_CPU_OFFSET (x64._GDTRBaseLoDword), MM_CPU_OFFSET (x64._GDTRBaseHiDword), FALSE}, // EFI_MM_SAVE_STATE_REGISTER_GDTBASE = 4
+ { 0, 8, 0, MM_CPU_OFFSET (x64._IDTRBaseLoDword), MM_CPU_OFFSET (x64._IDTRBaseLoDword), FALSE}, // EFI_MM_SAVE_STATE_REGISTER_IDTBASE = 5
+ { 0, 8, 0, MM_CPU_OFFSET (x64._LDTRBaseLoDword), MM_CPU_OFFSET (x64._LDTRBaseLoDword), FALSE}, // EFI_MM_SAVE_STATE_REGISTER_LDTBASE = 6
+ { 0, 2, 0, MM_CPU_OFFSET (x64._GDTRLimit), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_GDTLIMIT = 7
+ { 0, 2, 0, MM_CPU_OFFSET (x64._IDTRLimit), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_IDTLIMIT = 8
+ { 0, 4, 0, MM_CPU_OFFSET (x64._LDTRLimit), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_LDTLIMIT = 9
+ { 0, 0, 0, 0, 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_LDTINFO = 10
+ { 4, 2, MM_CPU_OFFSET (x86._ES), MM_CPU_OFFSET (x64._ES), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_ES = 20
+ { 4, 2, MM_CPU_OFFSET (x86._CS), MM_CPU_OFFSET (x64._CS), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_CS = 21
+ { 4, 2, MM_CPU_OFFSET (x86._SS), MM_CPU_OFFSET (x64._SS), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_SS = 22
+ { 4, 2, MM_CPU_OFFSET (x86._DS), MM_CPU_OFFSET (x64._DS), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_DS = 23
+ { 4, 2, MM_CPU_OFFSET (x86._FS), MM_CPU_OFFSET (x64._FS), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_FS = 24
+ { 4, 2, MM_CPU_OFFSET (x86._GS), MM_CPU_OFFSET (x64._GS), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_GS = 25
+ { 0, 2, 0, MM_CPU_OFFSET (x64._LDTR), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_LDTR_SEL = 26
+ { 0, 2, 0, MM_CPU_OFFSET (x64._TR), 0, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_TR_SEL = 27
+ { 4, 8, MM_CPU_OFFSET (x86._DR7), MM_CPU_OFFSET (x64._DR7), MM_CPU_OFFSET (x64._DR7) + 4, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_DR7 = 28
+ { 4, 8, MM_CPU_OFFSET (x86._DR6), MM_CPU_OFFSET (x64._DR6), MM_CPU_OFFSET (x64._DR6) + 4, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_DR6 = 29
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R8), MM_CPU_OFFSET (x64._R8) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R8 = 30
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R9), MM_CPU_OFFSET (x64._R9) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R9 = 31
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R10), MM_CPU_OFFSET (x64._R10) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R10 = 32
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R11), MM_CPU_OFFSET (x64._R11) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R11 = 33
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R12), MM_CPU_OFFSET (x64._R12) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R12 = 34
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R13), MM_CPU_OFFSET (x64._R13) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R13 = 35
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R14), MM_CPU_OFFSET (x64._R14) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R14 = 36
+ { 0, 8, 0, MM_CPU_OFFSET (x64._R15), MM_CPU_OFFSET (x64._R15) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_R15 = 37
+ { 4, 8, MM_CPU_OFFSET (x86._EAX), MM_CPU_OFFSET (x64._RAX), MM_CPU_OFFSET (x64._RAX) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RAX = 38
+ { 4, 8, MM_CPU_OFFSET (x86._EBX), MM_CPU_OFFSET (x64._RBX), MM_CPU_OFFSET (x64._RBX) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RBX = 39
+ { 4, 8, MM_CPU_OFFSET (x86._ECX), MM_CPU_OFFSET (x64._RCX), MM_CPU_OFFSET (x64._RCX) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RBX = 39
+ { 4, 8, MM_CPU_OFFSET (x86._EDX), MM_CPU_OFFSET (x64._RDX), MM_CPU_OFFSET (x64._RDX) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RDX = 41
+ { 4, 8, MM_CPU_OFFSET (x86._ESP), MM_CPU_OFFSET (x64._RSP), MM_CPU_OFFSET (x64._RSP) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RSP = 42
+ { 4, 8, MM_CPU_OFFSET (x86._EBP), MM_CPU_OFFSET (x64._RBP), MM_CPU_OFFSET (x64._RBP) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RBP = 43
+ { 4, 8, MM_CPU_OFFSET (x86._ESI), MM_CPU_OFFSET (x64._RSI), MM_CPU_OFFSET (x64._RSI) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RSI = 44
+ { 4, 8, MM_CPU_OFFSET (x86._EDI), MM_CPU_OFFSET (x64._RDI), MM_CPU_OFFSET (x64._RDI) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RDI = 45
+ { 4, 8, MM_CPU_OFFSET (x86._EIP), MM_CPU_OFFSET (x64._RIP), MM_CPU_OFFSET (x64._RIP) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RIP = 46
+
+ { 4, 8, MM_CPU_OFFSET (x86._EFLAGS), MM_CPU_OFFSET (x64._RFLAGS), MM_CPU_OFFSET (x64._RFLAGS) + 4, TRUE}, // EFI_MM_SAVE_STATE_REGISTER_RFLAGS = 51
+ { 4, 8, MM_CPU_OFFSET (x86._CR0), MM_CPU_OFFSET (x64._CR0), MM_CPU_OFFSET (x64._CR0) + 4, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_CR0 = 52
+ { 4, 8, MM_CPU_OFFSET (x86._CR3), MM_CPU_OFFSET (x64._CR3), MM_CPU_OFFSET (x64._CR3) + 4, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_CR3 = 53
+ { 0, 8, 0, MM_CPU_OFFSET (x64._CR4), MM_CPU_OFFSET (x64._CR4) + 4, FALSE}, // EFI_MM_SAVE_STATE_REGISTER_CR4 = 54
+ { 0, 0, 0, 0, 0 }
+};
+
+/**
+ Read a save state register on the target processor. If this function
+ returns EFI_UNSUPPORTED, then the caller is responsible for reading the
+ MM Save State register.
+
+ @param[in] CpuIndex The index of the CPU to read the Save State register.
+ The value must be between 0 and the NumberOfCpus field in
+ the System Management System Table (SMST).
+ @param[in] Register The MM Save State register to read.
+ @param[in] Width The number of bytes to read from the CPU save state.
+ @param[out] Buffer Upon return, this holds the CPU register value read
+ from the save state.
+
+ @retval EFI_SUCCESS The register was read from Save State.
+ @retval EFI_INVALID_PARAMTER Buffer is NULL.
+ @retval EFI_UNSUPPORTED This function does not support reading Register.
+ @retval EFI_NOT_FOUND If desired Register not found.
+**/
+EFI_STATUS
+EFIAPI
+MmSaveStateReadRegister (
+ IN UINTN CpuIndex,
+ IN EFI_MM_SAVE_STATE_REGISTER Register,
+ IN UINTN Width,
+ OUT VOID *Buffer
+ )
+{
+ UINT32 SmmRevId;
+ EFI_MM_SAVE_STATE_IO_INFO *IoInfo;
+ AMD_SMRAM_SAVE_STATE_MAP *CpuSaveState;
+ UINT8 DataWidth;
+
+ // Read CPU State
+ CpuSaveState = (AMD_SMRAM_SAVE_STATE_MAP *)gSmst->CpuSaveState[CpuIndex];
+
+ // Check for special EFI_MM_SAVE_STATE_REGISTER_LMA
+ if (Register == EFI_MM_SAVE_STATE_REGISTER_LMA) {
+ // Only byte access is supported for this register
+ if (Width != 1) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ *(UINT8 *)Buffer = MmSaveStateGetRegisterLma ();
+
+ return EFI_SUCCESS;
+ }
+
+ // Check for special EFI_MM_SAVE_STATE_REGISTER_IO
+ if (Register == EFI_MM_SAVE_STATE_REGISTER_IO) {
+ //
+ // Get SMM Revision ID
+ //
+ MmSaveStateReadRegisterByIndex (CpuIndex, AMD_MM_SAVE_STATE_REGISTER_SMMREVID_INDEX, sizeof (SmmRevId), &SmmRevId);
+
+ //
+ // See if the CPU supports the IOMisc register in the save state
+ //
+ if (SmmRevId < AMD_SMM_MIN_REV_ID_X64) {
+ return EFI_NOT_FOUND;
+ }
+
+ // Check if IO Restart Dword [IO Trap] is valid or not using bit 1.
+ if (!(CpuSaveState->x64.IO_DWord & 0x02u)) {
+ return EFI_NOT_FOUND;
+ }
+
+ // Zero the IoInfo structure that will be returned in Buffer
+ IoInfo = (EFI_MM_SAVE_STATE_IO_INFO *)Buffer;
+ ZeroMem (IoInfo, sizeof (EFI_MM_SAVE_STATE_IO_INFO));
+
+ IoInfo->IoPort = (UINT16)(CpuSaveState->x64.IO_DWord >> 16u);
+
+ if (CpuSaveState->x64.IO_DWord & 0x10u) {
+ IoInfo->IoWidth = EFI_MM_SAVE_STATE_IO_WIDTH_UINT8;
+ DataWidth = 0x01u;
+ } else if (CpuSaveState->x64.IO_DWord & 0x20u) {
+ IoInfo->IoWidth = EFI_MM_SAVE_STATE_IO_WIDTH_UINT16;
+ DataWidth = 0x02u;
+ } else {
+ IoInfo->IoWidth = EFI_MM_SAVE_STATE_IO_WIDTH_UINT32;
+ DataWidth = 0x04u;
+ }
+
+ if (CpuSaveState->x64.IO_DWord & 0x01u) {
+ IoInfo->IoType = EFI_MM_SAVE_STATE_IO_TYPE_INPUT;
+ } else {
+ IoInfo->IoType = EFI_MM_SAVE_STATE_IO_TYPE_OUTPUT;
+ }
+
+ if ((IoInfo->IoType == EFI_MM_SAVE_STATE_IO_TYPE_INPUT) || (IoInfo->IoType == EFI_MM_SAVE_STATE_IO_TYPE_OUTPUT)) {
+ MmSaveStateReadRegister (CpuIndex, EFI_MM_SAVE_STATE_REGISTER_RAX, DataWidth, &IoInfo->IoData);
+ }
+
+ return EFI_SUCCESS;
+ }
+
+ // Convert Register to a register lookup table index
+ return MmSaveStateReadRegisterByIndex (CpuIndex, MmSaveStateGetRegisterIndex (Register, AMD_MM_SAVE_STATE_REGISTER_MAX_INDEX), Width, Buffer);
+}
+
+/**
+ Writes a save state register on the target processor. If this function
+ returns EFI_UNSUPPORTED, then the caller is responsible for writing the
+ MM save state register.
+
+ @param[in] CpuIndex The index of the CPU to write the MM Save State. The
+ value must be between 0 and the NumberOfCpus field in
+ the System Management System Table (SMST).
+ @param[in] Register The MM Save State register to write.
+ @param[in] Width The number of bytes to write to the CPU save state.
+ @param[in] Buffer Upon entry, this holds the new CPU register value.
+
+ @retval EFI_SUCCESS The register was written to Save State.
+ @retval EFI_INVALID_PARAMTER Buffer is NULL.
+ @retval EFI_UNSUPPORTED This function does not support writing Register.
+ @retval EFI_NOT_FOUND If desired Register not found.
+**/
+EFI_STATUS
+EFIAPI
+MmSaveStateWriteRegister (
+ IN UINTN CpuIndex,
+ IN EFI_MM_SAVE_STATE_REGISTER Register,
+ IN UINTN Width,
+ IN CONST VOID *Buffer
+ )
+{
+ UINTN RegisterIndex;
+ AMD_SMRAM_SAVE_STATE_MAP *CpuSaveState;
+
+ //
+ // Writes to EFI_MM_SAVE_STATE_REGISTER_LMA are ignored
+ //
+ if (Register == EFI_MM_SAVE_STATE_REGISTER_LMA) {
+ return EFI_SUCCESS;
+ }
+
+ //
+ // Writes to EFI_MM_SAVE_STATE_REGISTER_IO are not supported
+ //
+ if (Register == EFI_MM_SAVE_STATE_REGISTER_IO) {
+ return EFI_NOT_FOUND;
+ }
+
+ //
+ // Convert Register to a register lookup table index
+ //
+ RegisterIndex = MmSaveStateGetRegisterIndex (Register, AMD_MM_SAVE_STATE_REGISTER_MAX_INDEX);
+ if (RegisterIndex == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ CpuSaveState = gSmst->CpuSaveState[CpuIndex];
+
+ //
+ // Do not write non-writable SaveState, because it will cause exception.
+ //
+ if (!mCpuWidthOffset[RegisterIndex].Writeable) {
+ return EFI_UNSUPPORTED;
+ }
+
+ //
+ // Check CPU mode
+ //
+ if (MmSaveStateGetRegisterLma () == EFI_MM_SAVE_STATE_REGISTER_LMA_32BIT) {
+ //
+ // If 32-bit mode width is zero, then the specified register can not be accessed
+ //
+ if (mCpuWidthOffset[RegisterIndex].Width32 == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ //
+ // If Width is bigger than the 32-bit mode width, then the specified register can not be accessed
+ //
+ if (Width > mCpuWidthOffset[RegisterIndex].Width32) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // Write SMM State register
+ //
+ ASSERT (CpuSaveState != NULL);
+ CopyMem ((UINT8 *)CpuSaveState + mCpuWidthOffset[RegisterIndex].Offset32, Buffer, Width);
+ } else {
+ //
+ // If 64-bit mode width is zero, then the specified register can not be accessed
+ //
+ if (mCpuWidthOffset[RegisterIndex].Width64 == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ //
+ // If Width is bigger than the 64-bit mode width, then the specified register can not be accessed
+ //
+ if (Width > mCpuWidthOffset[RegisterIndex].Width64) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // Write lower 32-bits of SMM State register
+ //
+ CopyMem ((UINT8 *)CpuSaveState + mCpuWidthOffset[RegisterIndex].Offset64Lo, Buffer, MIN (4, Width));
+ if (Width >= 4) {
+ //
+ // Write upper 32-bits of SMM State register
+ //
+ CopyMem ((UINT8 *)CpuSaveState + mCpuWidthOffset[RegisterIndex].Offset64Hi, (UINT8 *)Buffer + 4, Width - 4);
+ }
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Returns LMA value of the Processor.
+
+ @retval UINT8 returns LMA bit value.
+**/
+UINT8
+MmSaveStateGetRegisterLma (
+ VOID
+ )
+{
+ UINT32 LMAValue;
+
+ LMAValue = (UINT32)AsmReadMsr64 (EFER_ADDRESS) & LMA;
+ if (LMAValue) {
+ return EFI_MM_SAVE_STATE_REGISTER_LMA_64BIT;
+ }
+
+ return EFI_MM_SAVE_STATE_REGISTER_LMA_32BIT;
+}
diff --git a/UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveStateLib.inf b/UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveStateLib.inf
new file mode 100644
index 0000000000..5c0685f283
--- /dev/null
+++ b/UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveStateLib.inf
@@ -0,0 +1,34 @@
+## @file
+# MM Smram save state service lib.
+#
+# This is MM Smram save state service lib that provide service to read and
+# save savestate area registers.
+#
+# Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+ INF_VERSION = 1.29
+ BASE_NAME = AmdMmSaveStateLib
+ FILE_GUID = FB7D0A60-E8D4-4EFA-90AA-B357BC569879
+ MODULE_TYPE = DXE_SMM_DRIVER
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = MmSaveStateLib
+
+[Sources]
+ MmSaveState.h
+ MmSaveStateCommon.c
+ AmdMmSaveState.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+ UefiCpuPkg/UefiCpuPkg.dec
+
+[LibraryClasses]
+ BaseLib
+ BaseMemoryLib
+ DebugLib
+ SmmServicesTableLib
diff --git a/UefiCpuPkg/Library/MmSaveStateLib/MmSaveState.h b/UefiCpuPkg/Library/MmSaveStateLib/MmSaveState.h
new file mode 100644
index 0000000000..c3499cbb3b
--- /dev/null
+++ b/UefiCpuPkg/Library/MmSaveStateLib/MmSaveState.h
@@ -0,0 +1,94 @@
+/** @file
+ SMRAM Save State Map header file.
+
+ Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.
+ Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef MM_SAVESTATE_H_
+#define MM_SAVESTATE_H_
+
+#include
+#include
+#include
+#include
+#include
+#include
+
+// Macro used to simplify the lookup table entries of type CPU_MM_SAVE_STATE_REGISTER_RANGE
+#define MM_REGISTER_RANGE(Start, End) { Start, End, End - Start + 1 }
+
+// Structure used to describe a range of registers
+typedef struct {
+ EFI_MM_SAVE_STATE_REGISTER Start;
+ EFI_MM_SAVE_STATE_REGISTER End;
+ UINTN Length;
+} CPU_MM_SAVE_STATE_REGISTER_RANGE;
+
+// Structure used to build a lookup table to retrieve the widths and offsets
+// associated with each supported EFI_MM_SAVE_STATE_REGISTER value
+
+typedef struct {
+ UINT8 Width32;
+ UINT8 Width64;
+ UINT16 Offset32;
+ UINT16 Offset64Lo;
+ UINT16 Offset64Hi;
+ BOOLEAN Writeable;
+} CPU_MM_SAVE_STATE_LOOKUP_ENTRY;
+
+/**
+ Returns LMA value of the Processor.
+
+ @retval UINT8 returns LMA bit value.
+**/
+UINT8
+MmSaveStateGetRegisterLma (
+ VOID
+ );
+
+/**
+ Read information from the CPU save state.
+
+ @param Register Specifies the CPU register to read form the save state.
+ @param RegOffset Offset for the next register index.
+
+ @retval 0 Register is not valid
+ @retval >0 Index into mCpuWidthOffset[] associated with Register
+
+**/
+UINTN
+MmSaveStateGetRegisterIndex (
+ IN EFI_MM_SAVE_STATE_REGISTER Register,
+ IN UINTN RegOffset
+ );
+
+/**
+ Read a CPU Save State register on the target processor.
+
+ This function abstracts the differences that whether the CPU Save State register is in the
+ IA32 CPU Save State Map or X64 CPU Save State Map.
+
+ This function supports reading a CPU Save State register in SMBase relocation handler.
+
+ @param[in] CpuIndex Specifies the zero-based index of the CPU save state.
+ @param[in] RegisterIndex Index into mCpuWidthOffset[] look up table.
+ @param[in] Width The number of bytes to read from the CPU save state.
+ @param[out] Buffer Upon return, this holds the CPU register value read from the save state.
+
+ @retval EFI_SUCCESS The register was read from Save State.
+ @retval EFI_NOT_FOUND The register is not defined for the Save State of Processor.
+ @retval EFI_INVALID_PARAMTER This or Buffer is NULL.
+
+**/
+EFI_STATUS
+MmSaveStateReadRegisterByIndex (
+ IN UINTN CpuIndex,
+ IN UINTN RegisterIndex,
+ IN UINTN Width,
+ OUT VOID *Buffer
+ );
+
+#endif
diff --git a/UefiCpuPkg/Library/MmSaveStateLib/MmSaveStateCommon.c b/UefiCpuPkg/Library/MmSaveStateLib/MmSaveStateCommon.c
new file mode 100644
index 0000000000..09c6c3f96f
--- /dev/null
+++ b/UefiCpuPkg/Library/MmSaveStateLib/MmSaveStateCommon.c
@@ -0,0 +1,132 @@
+/** @file
+ Provides common supporting function to access SMRAM Save State Map
+
+ Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.
+ Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "MmSaveState.h"
+
+// Table used by MmSaveStateGetRegisterIndex() to convert an EFI_MM_SAVE_STATE_REGISTER
+// value to an index into a table of type CPU_MM_SAVE_STATE_LOOKUP_ENTRY
+CONST CPU_MM_SAVE_STATE_REGISTER_RANGE mCpuRegisterRanges[] = {
+ MM_REGISTER_RANGE (EFI_MM_SAVE_STATE_REGISTER_GDTBASE, EFI_MM_SAVE_STATE_REGISTER_LDTINFO),
+ MM_REGISTER_RANGE (EFI_MM_SAVE_STATE_REGISTER_ES, EFI_MM_SAVE_STATE_REGISTER_RIP),
+ MM_REGISTER_RANGE (EFI_MM_SAVE_STATE_REGISTER_RFLAGS, EFI_MM_SAVE_STATE_REGISTER_CR4),
+ { (EFI_MM_SAVE_STATE_REGISTER)0, (EFI_MM_SAVE_STATE_REGISTER)0, 0}
+};
+
+extern CONST CPU_MM_SAVE_STATE_LOOKUP_ENTRY mCpuWidthOffset[];
+
+/**
+ Read information from the CPU save state.
+
+ @param Register Specifies the CPU register to read form the save state.
+ @param RegOffset Offset for the next register index.
+
+ @retval 0 Register is not valid
+ @retval >0 Index into mCpuWidthOffset[] associated with Register
+
+**/
+UINTN
+MmSaveStateGetRegisterIndex (
+ IN EFI_MM_SAVE_STATE_REGISTER Register,
+ IN UINTN RegOffset
+ )
+{
+ UINTN Index;
+ UINTN Offset;
+
+ for (Index = 0, Offset = RegOffset; mCpuRegisterRanges[Index].Length != 0; Index++) {
+ if ((Register >= mCpuRegisterRanges[Index].Start) && (Register <= mCpuRegisterRanges[Index].End)) {
+ return Register - mCpuRegisterRanges[Index].Start + Offset;
+ }
+
+ Offset += mCpuRegisterRanges[Index].Length;
+ }
+
+ return 0;
+}
+
+/**
+ Read a CPU Save State register on the target processor.
+
+ This function abstracts the differences that whether the CPU Save State register is in the
+ IA32 CPU Save State Map or X64 CPU Save State Map.
+
+ This function supports reading a CPU Save State register in SMBase relocation handler.
+
+ @param[in] CpuIndex Specifies the zero-based index of the CPU save state.
+ @param[in] RegisterIndex Index into mCpuWidthOffset[] look up table.
+ @param[in] Width The number of bytes to read from the CPU save state.
+ @param[out] Buffer Upon return, this holds the CPU register value read from the save state.
+
+ @retval EFI_SUCCESS The register was read from Save State.
+ @retval EFI_NOT_FOUND The register is not defined for the Save State of Processor.
+ @retval EFI_INVALID_PARAMTER This or Buffer is NULL.
+
+**/
+EFI_STATUS
+MmSaveStateReadRegisterByIndex (
+ IN UINTN CpuIndex,
+ IN UINTN RegisterIndex,
+ IN UINTN Width,
+ OUT VOID *Buffer
+ )
+{
+ if (RegisterIndex == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ if (MmSaveStateGetRegisterLma () == EFI_MM_SAVE_STATE_REGISTER_LMA_32BIT) {
+ //
+ // If 32-bit mode width is zero, then the specified register can not be accessed
+ //
+ if (mCpuWidthOffset[RegisterIndex].Width32 == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ //
+ // If Width is bigger than the 32-bit mode width, then the specified register can not be accessed
+ //
+ if (Width > mCpuWidthOffset[RegisterIndex].Width32) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // Write return buffer
+ //
+ ASSERT (gSmst->CpuSaveState[CpuIndex] != NULL);
+ CopyMem (Buffer, (UINT8 *)gSmst->CpuSaveState[CpuIndex] + mCpuWidthOffset[RegisterIndex].Offset32, Width);
+ } else {
+ //
+ // If 64-bit mode width is zero, then the specified register can not be accessed
+ //
+ if (mCpuWidthOffset[RegisterIndex].Width64 == 0) {
+ return EFI_NOT_FOUND;
+ }
+
+ //
+ // If Width is bigger than the 64-bit mode width, then the specified register can not be accessed
+ //
+ if (Width > mCpuWidthOffset[RegisterIndex].Width64) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ //
+ // Write lower 32-bits of return buffer
+ //
+ CopyMem (Buffer, (UINT8 *)gSmst->CpuSaveState[CpuIndex] + mCpuWidthOffset[RegisterIndex].Offset64Lo, MIN (4, Width));
+ if (Width > 4) {
+ //
+ // Write upper 32-bits of return buffer
+ //
+ CopyMem ((UINT8 *)Buffer + 4, (UINT8 *)gSmst->CpuSaveState[CpuIndex] + mCpuWidthOffset[RegisterIndex].Offset64Hi, Width - 4);
+ }
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/UefiCpuPkg/UefiCpuPkg.dsc b/UefiCpuPkg/UefiCpuPkg.dsc
index da95f58ca6..e2300e7993 100644
--- a/UefiCpuPkg/UefiCpuPkg.dsc
+++ b/UefiCpuPkg/UefiCpuPkg.dsc
@@ -2,6 +2,7 @@
# UefiCpuPkg Package
#
# Copyright (c) 2007 - 2023, Intel Corporation. All rights reserved.
+# Copyright (C) 2023 Advanced Micro Devices, Inc. All rights reserved.
#
# SPDX-License-Identifier: BSD-2-Clause-Patent
#
@@ -99,6 +100,7 @@
MemoryAllocationLib|MdePkg/Library/SmmMemoryAllocationLib/SmmMemoryAllocationLib.inf
HobLib|MdePkg/Library/DxeHobLib/DxeHobLib.inf
CpuExceptionHandlerLib|UefiCpuPkg/Library/CpuExceptionHandlerLib/SmmCpuExceptionHandlerLib.inf
+ MmSaveStateLib|UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveStateLib.inf
[LibraryClasses.common.MM_STANDALONE]
MmServicesTableLib|MdePkg/Library/StandaloneMmServicesTableLib/StandaloneMmServicesTableLib.inf
@@ -182,6 +184,7 @@
UnitTestResultReportLib|UnitTestFrameworkPkg/Library/UnitTestResultReportLib/UnitTestResultReportLibConOut.inf
}
+ UefiCpuPkg/Library/MmSaveStateLib/AmdMmSaveStateLib.inf
[Components.X64]
UefiCpuPkg/Library/CpuExceptionHandlerLib/UnitTest/DxeCpuExceptionHandlerLibUnitTest.inf