1 /** @file
2 Module produce EFI_PEI_READ_ONLY_VARIABLE2_PPI on top of EFI_PEI_READ_ONLY_VARIABLE_PPI.
3 UEFI PI Spec supersedes Intel's Framework Specs.
4 EFI_PEI_READ_ONLY_VARIABLE_PPI defined in Intel Framework Pkg is replaced by EFI_PEI_READ_ONLY_VARIABLE2_PPI
5 in MdePkg.
6 This module produces EFI_PEI_READ_ONLY_VARIABLE2_PPI on top of EFI_PEI_READ_ONLY_VARIABLE_PPI.
7 This module is used on platform when both of these two conditions are true:
8 1) Framework module produces EFI_PEI_READ_ONLY_VARIABLE_PPI is present.
9 2) The platform has PI modules that only consumes EFI_PEI_READ_ONLY_VARIABLE2_PPI.
10
11 This module can't be used together with ReadOnlyVariableToReadOnlyVariable2Thunk module.
12
13
14 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
15 This program and the accompanying materials
16 are licensed and made available under the terms and conditions of the BSD License
17 which accompanies this distribution. The full text of the license may be found at
18 http://opensource.org/licenses/bsd-license.php
19
20 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
21 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
22 Module Name:
23
24 **/
25
26 #include <PiPei.h>
27 #include <Ppi/ReadOnlyVariable2.h>
28 #include <Ppi/ReadOnlyVariable.h>
29 #include <Library/DebugLib.h>
30 #include <Library/PeiServicesTablePointerLib.h>
31 #include <Library/PeiServicesLib.h>
32
33 /**
34 Provide the read variable functionality of the variable services.
35
36 @param This A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
37 @param VariableName A pointer to a null-terminated string that is the variable's name.
38 @param VariableGuid A pointer to an EFI_GUID that is the variable's GUID. The combination of
39 VariableGuid and VariableName must be unique.
40 @param Attributes If non-NULL, on return, points to the variable's attributes.
41 @param DataSize On entry, points to the size in bytes of the Data buffer.
42 On return, points to the size of the data returned in Data.
43 @param Data Points to the buffer which will hold the returned variable value.
44
45 @retval EFI_SUCCESS The interface could be successfully installed
46 @retval EFI_NOT_FOUND The variable could not be discovered
47 @retval EFI_BUFFER_TOO_SMALL The caller buffer is not large enough
48
49 **/
50 EFI_STATUS
51 EFIAPI
PeiGetVariable(IN CONST EFI_PEI_READ_ONLY_VARIABLE2_PPI * This,IN CONST CHAR16 * VariableName,IN CONST EFI_GUID * VariableGuid,OUT UINT32 * Attributes,IN OUT UINTN * DataSize,OUT VOID * Data)52 PeiGetVariable (
53 IN CONST EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
54 IN CONST CHAR16 *VariableName,
55 IN CONST EFI_GUID *VariableGuid,
56 OUT UINT32 *Attributes,
57 IN OUT UINTN *DataSize,
58 OUT VOID *Data
59 )
60 {
61 EFI_STATUS Status;
62 EFI_PEI_READ_ONLY_VARIABLE_PPI *ReadOnlyVariable;
63
64 Status = PeiServicesLocatePpi (
65 &gEfiPeiReadOnlyVariablePpiGuid,
66 0,
67 NULL,
68 (VOID **)&ReadOnlyVariable
69 );
70 ASSERT_EFI_ERROR (Status);
71
72 return ReadOnlyVariable->PeiGetVariable (
73 (EFI_PEI_SERVICES **) GetPeiServicesTablePointer (),
74 (CHAR16 *)VariableName,
75 (EFI_GUID *)VariableGuid,
76 Attributes,
77 DataSize,
78 Data
79 );
80 }
81
82 /**
83 Provide the get next variable functionality of the variable services.
84
85 @param This A pointer to this instance of the EFI_PEI_READ_ONLY_VARIABLE2_PPI.
86
87 @param VariableNameSize On entry, points to the size of the buffer pointed to by VariableName.
88 @param VariableName On entry, a pointer to a null-terminated string that is the variable's name.
89 On return, points to the next variable's null-terminated name string.
90
91 @param VariableGuid On entry, a pointer to an EFI_GUID that is the variable's GUID.
92 On return, a pointer to the next variable's GUID.
93
94 @retval EFI_SUCCESS The interface could be successfully installed
95 @retval EFI_NOT_FOUND The variable could not be discovered
96
97 **/
98 EFI_STATUS
99 EFIAPI
PeiGetNextVariableName(IN CONST EFI_PEI_READ_ONLY_VARIABLE2_PPI * This,IN OUT UINTN * VariableNameSize,IN OUT CHAR16 * VariableName,IN OUT EFI_GUID * VariableGuid)100 PeiGetNextVariableName (
101 IN CONST EFI_PEI_READ_ONLY_VARIABLE2_PPI *This,
102 IN OUT UINTN *VariableNameSize,
103 IN OUT CHAR16 *VariableName,
104 IN OUT EFI_GUID *VariableGuid
105 )
106 {
107 EFI_STATUS Status;
108 EFI_PEI_READ_ONLY_VARIABLE_PPI *ReadOnlyVariable;
109
110 Status = PeiServicesLocatePpi (
111 &gEfiPeiReadOnlyVariablePpiGuid,
112 0,
113 NULL,
114 (VOID **)&ReadOnlyVariable
115 );
116 ASSERT_EFI_ERROR (Status);
117
118 return ReadOnlyVariable->PeiGetNextVariableName (
119 (EFI_PEI_SERVICES **) GetPeiServicesTablePointer (),
120 VariableNameSize,
121 VariableName,
122 VariableGuid
123 );
124 }
125
126 //
127 // Module globals
128 //
129 EFI_PEI_READ_ONLY_VARIABLE2_PPI mVariablePpi = {
130 PeiGetVariable,
131 PeiGetNextVariableName
132 };
133
134 EFI_PEI_PPI_DESCRIPTOR mPpiListVariable = {
135 (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
136 &gEfiPeiReadOnlyVariable2PpiGuid,
137 &mVariablePpi
138 };
139
140 /**
141 User entry for this PEIM driver.
142
143 @param FileHandle Handle of the file being invoked.
144 @param PeiServices Describes the list of possible PEI Services.
145
146 @retval EFI_SUCCESS ReadOnlyVariable2 PPI is successfully installed.
147 @return Others ReadOnlyVariable2 PPI is not successfully installed.
148
149 **/
150 EFI_STATUS
151 EFIAPI
PeimInitializeReadOnlyVariable2(IN EFI_PEI_FILE_HANDLE FileHandle,IN CONST EFI_PEI_SERVICES ** PeiServices)152 PeimInitializeReadOnlyVariable2 (
153 IN EFI_PEI_FILE_HANDLE FileHandle,
154 IN CONST EFI_PEI_SERVICES **PeiServices
155 )
156 {
157 //
158 // This thunk module can only be used together with a PI PEI core, as we
159 // assume PeiServices Pointer Table can be located in a standard way defined
160 // in PI spec.
161 //
162 ASSERT ((*PeiServices)->Hdr.Revision >= 0x00010000);
163
164 //
165 // Developer should make sure ReadOnlyVariable2ToReadOnlyVariable module is not present. or else, the call chain will form a
166 // infinite loop: ReadOnlyVariable2 -> ReadOnlyVariable -> ReadOnlyVariable2 -> .....
167 //
168 //
169 // Publish the variable capability to other modules
170 //
171 return PeiServicesInstallPpi (&mPpiListVariable);
172 }
173