+/** @file\r
+ EDKII PEI Variable PPI provides an implementation of variables\r
+ intended for use as a means to store data in the PEI environment.\r
+\r
+ Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>\r
+ SPDX-License-Identifier: BSD-2-Clause-Patent\r
+\r
+**/\r
+\r
+#ifndef EDKII_PEI_VARIABLE_PPI_H_\r
+#define EDKII_PEI_VARIABLE_PPI_H_\r
+\r
+#define EDKII_PEI_VARIABLE_PPI_GUID \\r
+ { \\r
+ 0xe7b2cd04, 0x4b14, 0x44c2, { 0xb7, 0x48, 0xce, 0xaf, 0x2b, 0x66, 0x4a, 0xb0 } \\r
+ }\r
+\r
+typedef struct _EDKII_PEI_VARIABLE_PPI EDKII_PEI_VARIABLE_PPI;\r
+\r
+/**\r
+ This service retrieves a variable's value using its name and GUID.\r
+\r
+ Read the specified variable from the UEFI variable store. If the Data\r
+ buffer is too small to hold the contents of the variable,\r
+ the error EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the\r
+ required buffer size to obtain the data.\r
+\r
+ @param[in] This A pointer to this instance of the EDKII_PEI_VARIABLE_PPI.\r
+ @param[in] VariableName A pointer to a null-terminated string that is the variable's name.\r
+ @param[in] VariableGuid A pointer to an EFI_GUID that is the variable's GUID. The combination of\r
+ VariableGuid and VariableName must be unique.\r
+ @param[out] Attributes If non-NULL, on return, points to the variable's attributes.\r
+ @param[in, out] DataSize On entry, points to the size in bytes of the Data buffer.\r
+ On return, points to the size of the data returned in Data.\r
+ @param[out] Data Points to the buffer which will hold the returned variable value.\r
+ May be NULL with a zero DataSize in order to determine the size of the\r
+ buffer needed.\r
+\r
+ @retval EFI_SUCCESS The variable was read successfully.\r
+ @retval EFI_NOT_FOUND The variable was not found.\r
+ @retval EFI_BUFFER_TOO_SMALL The DataSize is too small for the resulting data.\r
+ DataSize is updated with the size required for\r
+ the specified variable.\r
+ @retval EFI_INVALID_PARAMETER VariableName, VariableGuid, DataSize or Data is NULL.\r
+ @retval EFI_DEVICE_ERROR The variable could not be retrieved because of a device error.\r
+\r
+**/\r
+typedef\r
+EFI_STATUS\r
+(EFIAPI *EDKII_PEI_GET_VARIABLE)(\r
+ IN CONST EDKII_PEI_VARIABLE_PPI *This,\r
+ IN CONST CHAR16 *VariableName,\r
+ IN CONST EFI_GUID *VariableGuid,\r
+ OUT UINT32 *Attributes OPTIONAL,\r
+ IN OUT UINTN *DataSize,\r
+ OUT VOID *Data OPTIONAL\r
+ );\r
+\r
+/**\r
+ Return the next variable name and GUID.\r
+\r
+ This function is called multiple times to retrieve the VariableName\r
+ and VariableGuid of all variables currently available in the system.\r
+ On each call, the previous results are passed into the interface,\r
+ and, on return, the interface returns the data for the next\r
+ variable. To get started, VariableName should initially contain L"\0"\r
+ and VariableNameSize should be sizeof(CHAR16). When the entire\r
+ variable list has been returned, EFI_NOT_FOUND is returned.\r
+\r
+ @param[in] This A pointer to this instance of the EDKII_PEI_VARIABLE_PPI.\r
+ @param[in, out] VariableNameSize On entry, points to the size of the buffer pointed to by VariableName.\r
+ On return, the size of the variable name buffer.\r
+ @param[in, out] VariableName On entry, a pointer to a null-terminated string that is the variable's name.\r
+ On return, points to the next variable's null-terminated name string.\r
+ @param[in, out] VariableGuid On entry, a pointer to an EFI_GUID that is the variable's GUID.\r
+ On return, a pointer to the next variable's GUID.\r
+\r
+ @retval EFI_SUCCESS The next variable name was read successfully.\r
+ @retval EFI_NOT_FOUND All variables have been enumerated.\r
+ @retval EFI_BUFFER_TOO_SMALL The VariableNameSize is too small for the resulting\r
+ data. VariableNameSize is updated with the size\r
+ required for the specified variable.\r
+ @retval EFI_INVALID_PARAMETER VariableName, VariableGuid or\r
+ VariableNameSize is NULL.\r
+ @retval EFI_DEVICE_ERROR The variable could not be retrieved because of a device error.\r
+\r
+**/\r
+typedef\r
+EFI_STATUS\r
+(EFIAPI *EDKII_PEI_GET_NEXT_VARIABLE_NAME)(\r
+ IN CONST EDKII_PEI_VARIABLE_PPI *This,\r
+ IN OUT UINTN *VariableNameSize,\r
+ IN OUT CHAR16 *VariableName,\r
+ IN OUT EFI_GUID *VariableGuid\r
+ );\r
+\r
+/**\r
+ Sets the value of a variable.\r
+\r
+ @param[in] This A pointer to this instance of the EDKII_PEI_VARIABLE_PPI.\r
+ @param[in] VariableName A Null-terminated string that is the name of the vendor's variable.\r
+ Each VariableName is unique for each VendorGuid. VariableName must\r
+ contain 1 or more characters. If VariableName is an empty string,\r
+ then EFI_INVALID_PARAMETER is returned.\r
+ @param[in] VendorGuid A unique identifier for the vendor.\r
+ @param[in] Attributes Attributes bitmask to set for the variable.\r
+ @param[in] DataSize The size in bytes of the Data buffer. Unless the EFI_VARIABLE_APPEND_WRITE\r
+ attribute is set, a size of zero causes the variable to be deleted. When the\r
+ EFI_VARIABLE_APPEND_WRITE attribute is set, then a SetVariable() call with a\r
+ DataSize of zero will not cause any change to the variable value.\r
+ @param[in] Data The contents for the variable.\r
+\r
+ @retval EFI_SUCCESS The firmware has successfully stored the variable and its data as\r
+ defined by the Attributes.\r
+ @retval EFI_INVALID_PARAMETER An invalid combination of attribute bits, name, and GUID was supplied, or the\r
+ DataSize exceeds the maximum allowed.\r
+ @retval EFI_INVALID_PARAMETER VariableName is an empty string.\r
+ @retval EFI_OUT_OF_RESOURCES Not enough storage is available to hold the variable and its data.\r
+ @retval EFI_DEVICE_ERROR The variable could not be stored due to a hardware error.\r
+ @retval EFI_WRITE_PROTECTED The variable in question is read-only.\r
+ @retval EFI_WRITE_PROTECTED The variable in question cannot be deleted.\r
+ @retval EFI_SECURITY_VIOLATION The variable could not be written due to EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS,\r
+ or EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS, or\r
+ EFI_VARIABLE_ENHANCED_AUTHENTICATED_ACCESS being set. Writing to authenticated\r
+ variables is not supported in the PEI environment. Updates to authenticated\r
+ variables can be requested during PEI via the EFI_AUTHENTICATED_VARIABLE_HOB, but\r
+ these updates won't be written to non-volatile storage until later in DXE.\r
+ The EFI_AUTHENTICATED_VARIABLE_HOB is a HOB with the GUID\r
+ gEfiAuthenticatedVariableGuid. This HOB contains a VARIABLE_STORE_HEADER followed\r
+ by one or more UEFI variables, which are stored as DWORD aligned tuples of\r
+ (VARIABLE_HEADER + CHAR16 VariableName + VariableData).\r
+ See MdeModulePkg/Include/Guid/VariableFormat.h for these data structure\r
+ definitions and MdeModulePkg/Universal/Variable/RuntimeDxe/VariableParsing.c for\r
+ an example of how to parse these data structures.\r
+ @retval EFI_NOT_FOUND The variable trying to be updated or deleted was not found.\r
+\r
+**/\r
+typedef\r
+EFI_STATUS\r
+(EFIAPI *EDKII_PEI_SET_VARIABLE)(\r
+ IN CONST EDKII_PEI_VARIABLE_PPI *This,\r
+ IN CHAR16 *VariableName,\r
+ IN EFI_GUID *VendorGuid,\r
+ IN UINT32 Attributes,\r
+ IN UINTN DataSize,\r
+ IN VOID *Data\r
+ );\r
+\r
+/**\r
+ Returns information about the UEFI variables.\r
+\r
+ @param[in] This A pointer to this instance of the EDKII_PEI_VARIABLE_PPI.\r
+ @param[in] Attributes Attributes bitmask to specify the type of variables on\r
+ which to return information.\r
+ @param[out] MaximumVariableStorageSize On output the maximum size of the storage space\r
+ available for the EFI variables associated with the\r
+ attributes specified.\r
+ @param[out] RemainingVariableStorageSize Returns the remaining size of the storage space\r
+ available for the EFI variables associated with the\r
+ attributes specified.\r
+ @param[out] MaximumVariableSize Returns the maximum size of the individual EFI\r
+ variables associated with the attributes specified.\r
+\r
+ @retval EFI_SUCCESS Valid answer returned.\r
+ @retval EFI_INVALID_PARAMETER An invalid combination of attribute bits was supplied\r
+ @retval EFI_UNSUPPORTED The attribute is not supported on this platform, and the\r
+ MaximumVariableStorageSize,\r
+ RemainingVariableStorageSize, MaximumVariableSize\r
+ are undefined.\r
+\r
+**/\r
+typedef\r
+EFI_STATUS\r
+(EFIAPI *EDKII_PEI_QUERY_VARIABLE_INFO)(\r
+ IN CONST EDKII_PEI_VARIABLE_PPI *This,\r
+ IN UINT32 Attributes,\r
+ OUT UINT64 *MaximumVariableStorageSize,\r
+ OUT UINT64 *RemainingVariableStorageSize,\r
+ OUT UINT64 *MaximumVariableSize\r
+ );\r
+\r
+///\r
+/// PEI Variable PPI is intended for use as a means\r
+/// to store data in the PEI environment.\r
+///\r
+struct _EDKII_PEI_VARIABLE_PPI {\r
+ EDKII_PEI_GET_VARIABLE GetVariable;\r
+ EDKII_PEI_GET_NEXT_VARIABLE_NAME GetNextVariableName;\r
+ EDKII_PEI_SET_VARIABLE SetVariable;\r
+ EDKII_PEI_QUERY_VARIABLE_INFO QueryVariableInfo;\r
+};\r
+\r
+extern EFI_GUID gEdkiiPeiVariablePpiGuid;\r
+\r
+#endif\r