Minor code enhancement.
[mirror_edk2.git] / IntelFrameworkPkg / Include / Ppi / ReadOnlyVariable.h
CommitLineData
3e5a3960 1/** @file\r
5259c97d 2 This file declares the Read-only Variable Service PPI, which is required by the framework spec.\r
7c6b0440 3\r
4a71b21a 4 These services provide a lightweight, read-only variant of the full EFI variable services. The\r
5 reason that these services are read-only is to reduce the complexity of flash management. Also,\r
6 some implementation of the PEI may use the same physical flash part for variable and PEIM\r
7 storage; as such, a write command to certain technologies would alter the contents of the entire part,\r
8 thus making the in situ PEIM execution not follow the required flow.\r
3e5a3960 9\r
2bbaeb0d 10 Copyright (c) 2006 - 2009, Intel Corporation\r
b80fbe85 11 All rights reserved. This program and the accompanying materials\r
12 are licensed and made available under the terms and conditions of the BSD License\r
13 which accompanies this distribution. The full text of the license may be found at\r
14 http://opensource.org/licenses/bsd-license.php\r
3e5a3960 15\r
b80fbe85 16 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
17 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
3e5a3960 18\r
55c1c87c 19 @par Revision Reference:\r
20 This PPI is defined in PEI CIS\r
21 Version 0.91.\r
3e5a3960 22**/\r
23\r
24#ifndef __PEI_READ_ONLY_VARIABLE_PPI_H__\r
25#define __PEI_READ_ONLY_VARIABLE_PPI_H__\r
26\r
27#define EFI_PEI_READ_ONLY_VARIABLE_ACCESS_PPI_GUID \\r
28 { \\r
29 0x3cdc90c6, 0x13fb, 0x4a75, {0x9e, 0x79, 0x59, 0xe9, 0xdd, 0x78, 0xb9, 0xfa } \\r
30 }\r
31\r
32typedef struct _EFI_PEI_READ_ONLY_VARIABLE_PPI EFI_PEI_READ_ONLY_VARIABLE_PPI;\r
33\r
22be261c 34///\r
35/// Variable attributes\r
36///@{\r
3e5a3960 37#define EFI_VARIABLE_NON_VOLATILE 0x00000001\r
38#define EFI_VARIABLE_BOOTSERVICE_ACCESS 0x00000002\r
39#define EFI_VARIABLE_RUNTIME_ACCESS 0x00000004\r
f527a6f1 40///\r
41/// Inconsistent with specification here: \r
42/// In Framework Spec, PeiCis0.91, neither the macro or its value is defined.\r
43/// Keeping this inconsistancy for backward compatibility.\r
44/// \r
1db0e83a 45#define EFI_VARIABLE_READ_ONLY 0x00000008\r
22be261c 46///@}\r
40038403 47\r
3e5a3960 48/**\r
49 Get Variable value by Name and GUID pair\r
50\r
22be261c 51 @param[in] PeiServices An indirect pointer to the PEI Services Table published by the PEI Foundation.\r
52 @param[in] VariableName A NULL-terminated Unicode string that is the name of the vendor's variable.\r
53 @param[in] VendorGuid A unique identifier for the vendor.\r
54 @param[out] Attributes This OPTIONAL parameter may be either NULL or\r
55 a pointer to the location in which to return\r
56 the attributes bitmask for the variable.\r
57 @param[in,out] DataSize On input, the size in bytes of the return Data buffer.\r
58 On output, the size of data returned in Data.\r
59 @param[out] Data The buffer to return the contents of the variable.\r
3e5a3960 60\r
61 @retval EFI_SUCCESS The function completed successfully.\r
62 @retval EFI_NOT_FOUND The variable was not found.\r
63 @retval EFI_BUFFER_TOO_SMALL The BufferSize is too small for the result.\r
64 @retval EFI_INVALID_PARAMETER One of the parameters has an invalid value.\r
65 @retval EFI_DEVICE_ERROR The variable could not be retrieved due to a hardware error.\r
66\r
67**/\r
68typedef\r
69EFI_STATUS\r
69686d56 70(EFIAPI *EFI_PEI_GET_VARIABLE)(\r
22be261c 71 IN EFI_PEI_SERVICES **PeiServices,\r
72 IN CHAR16 *VariableName,\r
73 IN EFI_GUID *VendorGuid,\r
74 OUT UINT32 *Attributes OPTIONAL,\r
75 IN OUT UINTN *DataSize,\r
76 OUT VOID *Data\r
3e5a3960 77 );\r
78\r
79/**\r
b80fbe85 80 This function can be called multiple times to retrieve the VariableName\r
81 and VendorGuid of all variables currently available in the system. On each call\r
5259c97d 82 to GetNextVariableName(), the previous results are passed into the interface,\r
b80fbe85 83 and on output the interface returns the next variable name data. When the\r
3e5a3960 84 entire variable list has been returned, the error EFI_NOT_FOUND is returned.\r
85\r
22be261c 86 @param[in] PeiServices An indirect pointer to the PEI Services Table published by the PEI Foundation.\r
87 @param[in] VariableNameSize The size of the VariableName buffer.\r
88 @param[in] VariableName On input, supplies the last VariableName that was\r
89 returned by GetNextVariableName(). On output, returns the Null-terminated\r
90 Unicode string of the current variable.\r
91 @param[in] VendorGuid On input, supplies the last VendorGuid that was\r
92 returned by GetNextVariableName(). On output, returns the VendorGuid\r
93 of the current variable.\r
3e5a3960 94\r
95 @retval EFI_SUCCESS The function completed successfully.\r
96 @retval EFI_NOT_FOUND The next variable was not found.\r
97 @retval EFI_BUFFER_TOO_SMALL The VariableNameSize is too small for the result.\r
98 @retval EFI_INVALID_PARAMETER One of the parameters has an invalid value.\r
99 @retval EFI_DEVICE_ERROR The variable name could not be retrieved due to a hardware error.\r
100\r
101**/\r
102typedef\r
103EFI_STATUS\r
69686d56 104(EFIAPI *EFI_PEI_GET_NEXT_VARIABLE_NAME)(\r
3e5a3960 105 IN EFI_PEI_SERVICES **PeiServices,\r
106 IN OUT UINTN *VariableNameSize,\r
107 IN OUT CHAR16 *VariableName,\r
108 IN OUT EFI_GUID *VendorGuid\r
109 );\r
110\r
7c6b0440 111///\r
112/// This PPI provides a lightweight, read-only variant of the full EFI\r
113/// variable services. \r
114///\r
3e5a3960 115struct _EFI_PEI_READ_ONLY_VARIABLE_PPI {\r
1db0e83a 116 ///\r
117 /// Inconsistent with specification here: \r
118 /// In Framework Spec, PeiCis0.91, the field is named as GetVariable and GetNextVariableName.\r
119 /// Keeping this inconsistance is for backward compatibility.\r
120 /// \r
121 EFI_PEI_GET_VARIABLE PeiGetVariable; ///< A service to ascertain a given variable name.\r
122 EFI_PEI_GET_NEXT_VARIABLE_NAME PeiGetNextVariableName; ///< A service to ascertain a variable based upon a given, known variable\r
3e5a3960 123};\r
124\r
125extern EFI_GUID gEfiPeiReadOnlyVariablePpiGuid;\r
126\r
22be261c 127#endif /* __PEI_READ_ONLY_VARIABLE_PPI_H__ */\r
128\r