EdkCompatibilityPkg/Compatibility/ReadOnlyVariableToReadOnlyVariable2Thunk/ReadOnlyVariableToReadOnlyVariable2Thunk.c

   1 /** @file
   2 Module produce EFI_PEI_READ_ONLY_VARIABLE_PPI on top of EFI_PEI_READ_ONLY_VARIABLE2_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_VARIABLE_PPI on top of EFI_PEI_READ_ONLY_VARIABLE2_PPI.
   7 # This module is used on platform when both of these two conditions are true:
   8 # 1) Framework module consumes EFI_PEI_READ_ONLY_VARIABLE_PPI is present.
   9 # 2) The platform has a PI module that only produces EFI_PEI_READ_ONLY_VARIABLE2_PPI.
  10
  11 This module can't be used together with ReadOnlyVariable2ToReadOnlyVariableThunk module.
  12
  13 Copyright (c) 2006 - 2008 Intel Corporation. <BR>
  14 All rights reserved. This program and the accompanying materials
  15 are licensed and made available under the terms and conditions of the BSD License
  16 which accompanies this distribution.  The full text of the license may be found at
  17 http://opensource.org/licenses/bsd-license.php
  18
  19 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  20 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  21 Module Name:
  22
  23 **/
  24
  25 #include <PiPei.h>
  26 #include <Ppi/ReadOnlyVariable.h>
  27 #include <Ppi/ReadOnlyVariable2.h>
  28 #include <Ppi/ReadOnlyVariableThunkPresent.h>
  29 #include <Library/DebugLib.h>
  30 #include <Library/PeiServicesLib.h>
  31
  32 //
  33 // Function Prototypes
  34 //
  35 EFI_STATUS
  36 EFIAPI
  37 PeiGetVariable (
  38   IN  EFI_PEI_SERVICES  **PeiServices,
  39   IN  CHAR16            *VariableName,
  40   IN  EFI_GUID          *VendorGuid,
  41   OUT UINT32            *Attributes OPTIONAL,
  42   IN  OUT UINTN         *DataSize,
  43   OUT VOID              *Data
  44   );
  45
  46 EFI_STATUS
  47 EFIAPI
  48 PeiGetNextVariableName (
  49   IN EFI_PEI_SERVICES  **PeiServices,
  50   IN OUT UINTN         *VariableNameSize,
  51   IN OUT CHAR16        *VariableName,
  52   IN OUT EFI_GUID      *VendorGuid
  53   );
  54
  55 //
  56 // Module globals
  57 //
  58 EFI_PEI_READ_ONLY_VARIABLE_PPI mVariablePpi = {
  59   PeiGetVariable,
  60   PeiGetNextVariableName
  61 };
  62
  63 EFI_PEI_PPI_DESCRIPTOR     mPpiListVariable = {
  64   (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  65   &gEfiPeiReadOnlyVariablePpiGuid,
  66   &mVariablePpi
  67 };
  68
  69 /**
  70   Standard entry point of a PEIM.
  71
  72   @param FfsHeadher  The FFS file header
  73   @param PeiServices  General purpose services available to every PEIM.
  74
  75   @retval EFI_SUCCESS If the gEfiPeiReadOnlyVariablePpiGuid interface could be successfully installed.
  76
  77 --*/
  78 EFI_STATUS
  79 EFIAPI
  80 PeimInitializeReadOnlyVariable (
  81   IN EFI_PEI_FILE_HANDLE     FfsHeader,
  82   IN CONST EFI_PEI_SERVICES  **PeiServices
  83   )
  84 {
  85   VOID        *Interface;
  86   EFI_STATUS  Status;
  87
  88   //
  89   // Make sure ReadOnlyVariableToReadOnlyVariable2 module is not present. If so, the call chain will form a
  90   // infinite loop: ReadOnlyVariable -> ReadOnlyVariable2 -> ReadOnlyVariable -> ....
  91   //
  92   Status = PeiServicesLocatePpi (&gPeiReadonlyVariableThunkPresentPpiGuid, 0, NULL, &Interface);
  93   ASSERT (Status == EFI_NOT_FOUND);
  94
  95   //
  96   // Publish the variable capability to other modules
  97   //
  98   return (*PeiServices)->InstallPpi (PeiServices, &mPpiListVariable);
  99 }
 100
 101 EFI_STATUS
 102 EFIAPI
 103 PeiGetVariable (
 104   IN  EFI_PEI_SERVICES  **PeiServices,
 105   IN  CHAR16            *VariableName,
 106   IN  EFI_GUID          *VendorGuid,
 107   OUT UINT32            *Attributes OPTIONAL,
 108   IN  OUT UINTN         *DataSize,
 109   OUT VOID              *Data
 110   )
 111 /*++
 112
 113 Routine Description:
 114
 115   Provide the read variable functionality of the variable services.
 116
 117 Arguments:
 118
 119   PeiServices - General purpose services available to every PEIM.
 120
 121   VariableName     - The variable name
 122
 123   VendorGuid       - The vendor's GUID
 124
 125   Attributes       - Pointer to the attribute
 126
 127   DataSize         - Size of data
 128
 129   Data             - Pointer to data
 130
 131 Returns:
 132
 133   EFI_SUCCESS           - The interface could be successfully installed
 134
 135   EFI_NOT_FOUND         - The variable could not be discovered
 136
 137   EFI_BUFFER_TOO_SMALL  - The caller buffer is not large enough
 138
 139 --*/
 140 {
 141   EFI_STATUS                      Status;
 142   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
 143
 144   Status = (*PeiServices)->LocatePpi (
 145                              (CONST EFI_PEI_SERVICES **)PeiServices,
 146                              &gEfiPeiReadOnlyVariable2PpiGuid,
 147                              0,
 148                              NULL,
 149                              (VOID **)&ReadOnlyVariable2
 150                              );
 151   ASSERT_EFI_ERROR (Status);
 152
 153   return ReadOnlyVariable2->GetVariable (
 154                               ReadOnlyVariable2,
 155                               VariableName,
 156                               VendorGuid,
 157                               Attributes,
 158                               DataSize,
 159                               Data
 160                               );
 161 }
 162
 163 EFI_STATUS
 164 EFIAPI
 165 PeiGetNextVariableName (
 166   IN EFI_PEI_SERVICES  **PeiServices,
 167   IN OUT UINTN         *VariableNameSize,
 168   IN OUT CHAR16        *VariableName,
 169   IN OUT EFI_GUID      *VendorGuid
 170   )
 171 /*++
 172
 173 Routine Description:
 174
 175   Provide the get next variable functionality of the variable services.
 176
 177 Arguments:
 178
 179   PeiServices        - General purpose services available to every PEIM.
 180   VariabvleNameSize  - The variable name's size.
 181   VariableName       - A pointer to the variable's name.
 182   VariableGuid       - A pointer to the EFI_GUID structure.
 183
 184   VariableNameSize - Size of the variable name
 185
 186   VariableName     - The variable name
 187
 188   VendorGuid       - The vendor's GUID
 189
 190 Returns:
 191
 192   EFI_SUCCESS - The interface could be successfully installed
 193
 194   EFI_NOT_FOUND - The variable could not be discovered
 195
 196 --*/
 197 {
 198   EFI_STATUS                      Status;
 199   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
 200
 201   Status = (*PeiServices)->LocatePpi (
 202                              (CONST EFI_PEI_SERVICES **)PeiServices,
 203                              &gEfiPeiReadOnlyVariable2PpiGuid,
 204                              0,
 205                              NULL,
 206                              (VOID **)&ReadOnlyVariable2
 207                              );
 208   ASSERT_EFI_ERROR (Status);
 209
 210   return ReadOnlyVariable2->NextVariableName (
 211                               ReadOnlyVariable2,
 212                               VariableNameSize,
 213                               VariableName,
 214                               VendorGuid
 215                               );
 216 }