QuarkPlatformPkg/Platform/Dxe/SaveMemoryConfig/SaveMemoryConfig.c

   1 /** @file
   2 This is the driver that locates the MemoryConfigurationData HOB, if it
   3 exists, and saves the data to nvRAM.
   4
   5 Copyright (c) 2013-2015 Intel Corporation.
   6
   7 This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <Library/DebugLib.h>
  18 #include <Library/HobLib.h>
  19 #include <Library/MemoryAllocationLib.h>
  20 #include <Library/UefiBootServicesTableLib.h>
  21 #include <Library/UefiRuntimeServicesTableLib.h>
  22 #include <Library/BaseMemoryLib.h>
  23 #include <Library/UefiDriverEntryPoint.h>
  24
  25 #include <Guid/MemoryConfigData.h>
  26 #include <Guid/DebugMask.h>
  27
  28 EFI_STATUS
  29 EFIAPI
  30 SaveMemoryConfigEntryPoint (
  31   IN EFI_HANDLE         ImageHandle,
  32   IN EFI_SYSTEM_TABLE   *SystemTable
  33   )
  34 /*++
  35
  36   Routine Description:
  37     This is the standard EFI driver point that detects whether there is a
  38     MemoryConfigurationData HOB and, if so, saves its data to nvRAM.
  39
  40   Arguments:
  41     ImageHandle   - Handle for the image of this driver
  42     SystemTable   - Pointer to the EFI System Table
  43
  44   Returns:
  45     EFI_SUCCESS   - if the data is successfully saved or there was no data
  46     EFI_NOT_FOUND - if the HOB list could not be located.
  47     EFI_UNLOAD_IMAGE - It is not success
  48
  49 --*/
  50 {
  51   EFI_STATUS  Status;
  52   VOID        *HobList;
  53   EFI_HOB_GUID_TYPE *GuidHob;
  54   VOID        *HobData;
  55   VOID        *VariableData;
  56   UINTN       DataSize;
  57   UINTN       BufferSize;
  58
  59   DataSize      = 0;
  60   VariableData  = NULL;
  61   GuidHob = NULL;
  62   HobList = NULL;
  63   HobData = NULL;
  64   Status  = EFI_UNSUPPORTED;
  65
  66   //
  67   // Get the HOB list.  If it is not present, then ASSERT.
  68   //
  69   HobList = GetHobList ();
  70   ASSERT (HobList != NULL);
  71
  72   //
  73   // Search for the Memory Configuration GUID HOB.  If it is not present, then
  74   // there's nothing we can do. It may not exist on the update path.
  75   //
  76   GuidHob = GetNextGuidHob (&gEfiMemoryConfigDataGuid, HobList);
  77   if (GuidHob != NULL) {
  78     HobData = GET_GUID_HOB_DATA (GuidHob);
  79     DataSize = GET_GUID_HOB_DATA_SIZE (GuidHob);
  80     //
  81     // Use the HOB to save Memory Configuration Data
  82     //
  83     BufferSize = DataSize;
  84     VariableData = AllocatePool (BufferSize);
  85     ASSERT (VariableData != NULL);
  86     Status = gRT->GetVariable (
  87                     EFI_MEMORY_CONFIG_DATA_NAME,
  88                     &gEfiMemoryConfigDataGuid,
  89                     NULL,
  90                     &BufferSize,
  91                     VariableData
  92                     );
  93     if (Status == EFI_BUFFER_TOO_SMALL) {
  94       gBS->FreePool (VariableData);
  95       VariableData = AllocatePool (BufferSize);
  96       ASSERT (VariableData != NULL);
  97       Status = gRT->GetVariable (
  98                       EFI_MEMORY_CONFIG_DATA_NAME,
  99                       &gEfiMemoryConfigDataGuid,
 100                       NULL,
 101                       &BufferSize,
 102                       VariableData
 103                       );
 104     }
 105
 106     if (EFI_ERROR(Status) || BufferSize != DataSize || CompareMem (HobData, VariableData, DataSize) != 0) {
 107       Status = gRT->SetVariable (
 108                       EFI_MEMORY_CONFIG_DATA_NAME,
 109                       &gEfiMemoryConfigDataGuid,
 110                       (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS),
 111                       DataSize,
 112                       HobData
 113                       );
 114       ASSERT((Status == EFI_SUCCESS) || (Status == EFI_OUT_OF_RESOURCES));
 115     }
 116
 117     gBS->FreePool (VariableData);
 118   }
 119
 120   //
 121   // This driver does not produce any protocol services, so always unload it.
 122   //
 123   return Status;
 124 }