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 SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Library/DebugLib.h>
  12 #include <Library/HobLib.h>
  13 #include <Library/MemoryAllocationLib.h>
  14 #include <Library/UefiBootServicesTableLib.h>
  15 #include <Library/UefiRuntimeServicesTableLib.h>
  16 #include <Library/BaseMemoryLib.h>
  17 #include <Library/UefiDriverEntryPoint.h>
  18
  19 #include <Guid/MemoryConfigData.h>
  20 #include <Guid/DebugMask.h>
  21
  22 EFI_STATUS
  23 EFIAPI
  24 SaveMemoryConfigEntryPoint (
  25   IN EFI_HANDLE         ImageHandle,
  26   IN EFI_SYSTEM_TABLE   *SystemTable
  27   )
  28 /*++
  29
  30   Routine Description:
  31     This is the standard EFI driver point that detects whether there is a
  32     MemoryConfigurationData HOB and, if so, saves its data to nvRAM.
  33
  34   Arguments:
  35     ImageHandle   - Handle for the image of this driver
  36     SystemTable   - Pointer to the EFI System Table
  37
  38   Returns:
  39     EFI_SUCCESS   - if the data is successfully saved or there was no data
  40     EFI_NOT_FOUND - if the HOB list could not be located.
  41     EFI_UNLOAD_IMAGE - It is not success
  42
  43 --*/
  44 {
  45   EFI_STATUS  Status;
  46   VOID        *HobList;
  47   EFI_HOB_GUID_TYPE *GuidHob;
  48   VOID        *HobData;
  49   VOID        *VariableData;
  50   UINTN       DataSize;
  51   UINTN       BufferSize;
  52
  53   DataSize      = 0;
  54   VariableData  = NULL;
  55   GuidHob = NULL;
  56   HobList = NULL;
  57   HobData = NULL;
  58   Status  = EFI_UNSUPPORTED;
  59
  60   //
  61   // Get the HOB list.  If it is not present, then ASSERT.
  62   //
  63   HobList = GetHobList ();
  64   ASSERT (HobList != NULL);
  65
  66   //
  67   // Search for the Memory Configuration GUID HOB.  If it is not present, then
  68   // there's nothing we can do. It may not exist on the update path.
  69   //
  70   GuidHob = GetNextGuidHob (&gEfiMemoryConfigDataGuid, HobList);
  71   if (GuidHob != NULL) {
  72     HobData = GET_GUID_HOB_DATA (GuidHob);
  73     DataSize = GET_GUID_HOB_DATA_SIZE (GuidHob);
  74     //
  75     // Use the HOB to save Memory Configuration Data
  76     //
  77     BufferSize = DataSize;
  78     VariableData = AllocatePool (BufferSize);
  79     ASSERT (VariableData != NULL);
  80     Status = gRT->GetVariable (
  81                     EFI_MEMORY_CONFIG_DATA_NAME,
  82                     &gEfiMemoryConfigDataGuid,
  83                     NULL,
  84                     &BufferSize,
  85                     VariableData
  86                     );
  87     if (Status == EFI_BUFFER_TOO_SMALL) {
  88       gBS->FreePool (VariableData);
  89       VariableData = AllocatePool (BufferSize);
  90       ASSERT (VariableData != NULL);
  91       Status = gRT->GetVariable (
  92                       EFI_MEMORY_CONFIG_DATA_NAME,
  93                       &gEfiMemoryConfigDataGuid,
  94                       NULL,
  95                       &BufferSize,
  96                       VariableData
  97                       );
  98     }
  99
 100     if (EFI_ERROR(Status) || BufferSize != DataSize || CompareMem (HobData, VariableData, DataSize) != 0) {
 101       Status = gRT->SetVariable (
 102                       EFI_MEMORY_CONFIG_DATA_NAME,
 103                       &gEfiMemoryConfigDataGuid,
 104                       (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS),
 105                       DataSize,
 106                       HobData
 107                       );
 108       ASSERT((Status == EFI_SUCCESS) || (Status == EFI_OUT_OF_RESOURCES));
 109     }
 110
 111     gBS->FreePool (VariableData);
 112   }
 113
 114   //
 115   // This driver does not produce any protocol services, so always unload it.
 116   //
 117   return Status;
 118 }