+{
+ EFI_HOB_GUID_TYPE *GuidHob;
+
+ if (VariableFlashInfo == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ GuidHob = GetFirstGuidHob (&gVariableFlashInfoHobGuid);
+ if (GuidHob == NULL) {
+ return EFI_NOT_FOUND;
+ }
+
+ *VariableFlashInfo = GET_GUID_HOB_DATA (GuidHob);
+
+ //
+ // Assert if more than one variable flash information HOB is present.
+ //
+ DEBUG_CODE (
+ if ((GetNextGuidHob (&gVariableFlashInfoHobGuid, GET_NEXT_HOB
(GuidHob)) != NULL)) {
+ DEBUG ((DEBUG_ERROR, "ERROR: Found two variable flash information
HOBs\n"));
+ ASSERT (FALSE);
+ }
+
+ );
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Get the base address and size for the NV storage area used for UEFI
variable storage.
+
+ @param[out] BaseAddress The NV storage base address.
+ @param[out] Length The NV storage length in bytes.
+
+ @retval EFI_SUCCESS NV storage information was found
successfully.
+ @retval EFI_INVALID_PARAMETER A required pointer parameter is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableFlashNvStorageInfo (
+ OUT EFI_PHYSICAL_ADDRESS *BaseAddress,
+ OUT UINT64 *Length
+ )
+{
+ EFI_STATUS Status;
+ VARIABLE_FLASH_INFO *VariableFlashInfo;
+
+ if ((BaseAddress == NULL) || (Length == NULL)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Status = GetVariableFlashInfoFromHob (&VariableFlashInfo);
+ if (!EFI_ERROR (Status)) {
+ *BaseAddress = VariableFlashInfo->NvVariableBaseAddress;
+ *Length = VariableFlashInfo->NvVariableLength;
+ } else {
+ *BaseAddress = (EFI_PHYSICAL_ADDRESS)(PcdGet64
(PcdFlashNvStorageVariableBase64) != 0 ?
+ PcdGet64
(PcdFlashNvStorageVariableBase64) :
+ PcdGet32
(PcdFlashNvStorageVariableBase)
+ );
+ *Length = (UINT64)PcdGet32 (PcdFlashNvStorageVariableSize);
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Get the base address and size for the fault tolerant write (FTW) spare
+ area used for UEFI variable storage.
+
+ @param[out] BaseAddress The FTW spare base address.
+ @param[out] Length The FTW spare length in bytes.
+
+ @retval EFI_SUCCESS FTW spare information was found
successfully.
+ @retval EFI_INVALID_PARAMETER A required pointer parameter is NULL.
+ @retval EFI_NOT_FOUND FTW spare information could not be
found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableFlashFtwSpareInfo (
+ OUT EFI_PHYSICAL_ADDRESS *BaseAddress,
+ OUT UINT64 *Length
+ )
+{
+ EFI_STATUS Status;
+ VARIABLE_FLASH_INFO *VariableFlashInfo;
+
+ if ((BaseAddress == NULL) || (Length == NULL)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Status = GetVariableFlashInfoFromHob (&VariableFlashInfo);
+ if (!EFI_ERROR (Status)) {
+ *BaseAddress = VariableFlashInfo->FtwSpareBaseAddress;
+ *Length = VariableFlashInfo->FtwSpareLength;
+ } else {
+ *BaseAddress = (EFI_PHYSICAL_ADDRESS)(PcdGet64
(PcdFlashNvStorageFtwSpareBase64) != 0 ?
+ PcdGet64
(PcdFlashNvStorageFtwSpareBase64) :
+ PcdGet32
(PcdFlashNvStorageFtwSpareBase)
+ );
+ *Length = (UINT64)PcdGet32 (PcdFlashNvStorageFtwSpareSize);
+ }
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Get the base address and size for the fault tolerant write (FTW)
working
+ area used for UEFI variable storage.
+
+ @param[out] BaseAddress The FTW working area base address.
+ @param[out] Length The FTW working area length in bytes.
+
+ @retval EFI_SUCCESS FTW working information was found
successfully.
+ @retval EFI_INVALID_PARAMETER A required pointer parameter is NULL.
+ @retval EFI_NOT_FOUND FTW working information could not
be found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableFlashFtwWorkingInfo (
+ OUT EFI_PHYSICAL_ADDRESS *BaseAddress,
+ OUT UINT64 *Length
+ )
+{
+ EFI_STATUS Status;
+ VARIABLE_FLASH_INFO *VariableFlashInfo;
+
+ if ((BaseAddress == NULL) || (Length == NULL)) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Status = GetVariableFlashInfoFromHob (&VariableFlashInfo);
+ if (!EFI_ERROR (Status)) {
+ *BaseAddress = VariableFlashInfo->FtwWorkingBaseAddress;
+ *Length = VariableFlashInfo->FtwWorkingLength;
+ } else {
+ *BaseAddress = (EFI_PHYSICAL_ADDRESS)(PcdGet64
(PcdFlashNvStorageFtwWorkingBase64) != 0 ?
+ PcdGet64
(PcdFlashNvStorageFtwWorkingBase64) :
+ PcdGet32
(PcdFlashNvStorageFtwWorkingBase)
+ );
+ *Length = (UINT64)PcdGet32 (PcdFlashNvStorageFtwWorkingSize);
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/MdeModulePkg/Include/Library/VariableFlashInfoLib.h
b/MdeModulePkg/Include/Library/VariableFlashInfoLib.h
new file mode 100644
index 000000000000..1367be9376ea
--- /dev/null
+++ b/MdeModulePkg/Include/Library/VariableFlashInfoLib.h
@@ -0,0 +1,68 @@
+/** @file
+ Variable Flash Information Library
+
+Copyright (c) Microsoft Corporation<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef VARIABLE_FLASH_INFO_LIB_H_
+#define VARIABLE_FLASH_INFO_LIB_H_
+
+/**
+ Get the base address and size for the NV storage area used for UEFI
variable storage.
+
+ @param[out] BaseAddress The NV storage base address.
+ @param[out] Length The NV storage length in bytes.
+
+ @retval EFI_SUCCESS NV storage information was found
successfully.
+ @retval EFI_INVALID_PARAMETER A required pointer parameter is NULL.
+ @retval EFI_NOT_FOUND NV storage information could not be
found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableFlashNvStorageInfo (
+ OUT EFI_PHYSICAL_ADDRESS *BaseAddress,
+ OUT UINT64 *Length
+ );
+
+/**
+ Get the base address and size for the fault tolerant write (FTW) spare
+ area used for UEFI variable storage.
+
+ @param[out] BaseAddress The FTW spare base address.
+ @param[out] Length The FTW spare length in bytes.
+
+ @retval EFI_SUCCESS FTW spare information was found
successfully.
+ @retval EFI_INVALID_PARAMETER A required pointer parameter is NULL.
+ @retval EFI_NOT_FOUND FTW spare information could not be
found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableFlashFtwSpareInfo (
+ OUT EFI_PHYSICAL_ADDRESS *BaseAddress,
+ OUT UINT64 *Length
+ );
+
+/**
+ Get the base address and size for the fault tolerant write (FTW)
working
+ area used for UEFI variable storage.
+
+ @param[out] BaseAddress The FTW working area base address.
+ @param[out] Length The FTW working area length in bytes.
+
+ @retval EFI_SUCCESS FTW working information was found
successfully.
+ @retval EFI_INVALID_PARAMETER A required pointer parameter is NULL.
+ @retval EFI_NOT_FOUND FTW working information could not
be found.
+
+**/
+EFI_STATUS
+EFIAPI
+GetVariableFlashFtwWorkingInfo (
+ OUT EFI_PHYSICAL_ADDRESS *BaseAddress,
+ OUT UINT64 *Length
+ );
+
+#endif
diff --git
a/MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.inf
b/MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.inf
new file mode 100644
index 000000000000..70175e75f9b1
--- /dev/null
+++
b/MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.inf
@@ -0,0 +1,48 @@
+## @file
+# Variable Flash Information Library
+#
+# Provides services to access UEFI variable flash information.
+#
+# Copyright (c) Microsoft Corporation<BR>
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+
+[Defines]
+ INF_VERSION = 0x00010005
+ BASE_NAME = BaseVariableFlashInfoLib
+ MODULE_UNI_FILE = BaseVariableFlashInfoLib.uni
+ FILE_GUID = DEC426C9-C92E-4BAD-8E93-3F61C261118B
+ MODULE_TYPE = BASE
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = VariableFlashInfoLib
+
+#
+# The following information is for reference only and not required by
the build tools.
+#
+# VALID_ARCHITECTURES = ANY
+#
+
+[Sources]
+ BaseVariableFlashInfoLib.c
+
+[Packages]
+ MdePkg/MdePkg.dec
+ MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+ DebugLib
+ HobLib
+
+[Guids]
+ gVariableFlashInfoHobGuid ## CONSUMES ## HOB
+
+[Pcd]
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableBase64
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableSize
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwSpareBase
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwSpareBase64
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwSpareSize
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingBase
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingBase64
## SOMETIMES_CONSUMES
+ gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize
## SOMETIMES_CONSUMES
diff --git
a/MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.uni
b/MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.uni
new file mode 100644
index 000000000000..9a5348fa02a0
--- /dev/null
+++
b/MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.uni
@@ -0,0 +1,12 @@
+// /** @file
+// Variable Flash Information Library
+//
+// Copyright (c) Microsoft Corporation<BR>
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+// **/
+
+#string STR_MODULE_ABSTRACT #language en-US "UEFI variable flash
information library"
+
+#string STR_MODULE_DESCRIPTION #language en-US "Provides services to
access UEFI variable flash information."
diff --git a/MdeModulePkg/MdeModulePkg.dec
b/MdeModulePkg/MdeModulePkg.dec
index 4e82f5836096..2bcb9f9453af 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -154,6 +154,10 @@ [LibraryClasses]
#
VariablePolicyHelperLib|Include/Library/VariablePolicyHelperLib.h
+ ## @libraryclass Provides services to access UEFI variable flash
information.
+ #
+ VariableFlashInfoLib|Include/Library/VariableFlashInfoLib.h
+
[Guids]
## MdeModule package token space guid
# Include/Guid/MdeModulePkgTokenSpace.h
diff --git a/MdeModulePkg/MdeModulePkg.dsc
b/MdeModulePkg/MdeModulePkg.dsc
index b1d83461865e..90a0a7ec4a7c 100644
--- a/MdeModulePkg/MdeModulePkg.dsc
+++ b/MdeModulePkg/MdeModulePkg.dsc
@@ -103,6 +103,7 @@ [LibraryClasses]
DisplayUpdateProgressLib|MdeModulePkg/Library/DisplayUpdateProgressLibGraphics/DisplayUpdateProgressLibGraphics.inf
VariablePolicyHelperLib|MdeModulePkg/Library/VariablePolicyHelperLib/VariablePolicyHelperLib.inf
MmUnblockMemoryLib|MdePkg/Library/MmUnblockMemoryLib/MmUnblockMemoryLibNull.inf
+
VariableFlashInfoLib|MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.inf
[LibraryClasses.EBC.PEIM]
IoLib|MdePkg/Library/PeiIoLibCpuIo/PeiIoLibCpuIo.inf
@@ -440,6 +441,7 @@ [Components]
MdeModulePkg/Library/FmpAuthenticationLibNull/FmpAuthenticationLibNull.inf
MdeModulePkg/Library/DxeCapsuleLibFmp/DxeCapsuleLib.inf
MdeModulePkg/Library/DxeCapsuleLibFmp/DxeRuntimeCapsuleLib.inf
+
MdeModulePkg/Library/BaseVariableFlashInfoLib/BaseVariableFlashInfoLib.inf
[Components.IA32, Components.X64, Components.AARCH64]
MdeModulePkg/Universal/EbcDxe/EbcDxe.inf
