MdeModulePkg/Library/PeiDebugPrintHobLib/PeiDebugPrintHobLib.c

/** @file
  NULL Library class that reads Debug Mask variable and if it exists makes a
  HOB that contains the debug mask.

  Copyright (c) 2011, Apple, Inc. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include <PiPei.h>

#include <Library/HobLib.h>
#include <Library/DebugLib.h>
#include <Library/PeiServicesLib.h>

#include <Ppi/ReadOnlyVariable2.h>
#include <Guid/DebugMask.h>


/**
  The constructor reads variable and sets HOB

  @param  FileHandle   The handle of FFS header the loaded driver.
  @param  PeiServices  The pointer to the PEI services.

  @retval EFI_SUCCESS  The constructor always returns EFI_SUCCESS.

**/
EFI_STATUS
EFIAPI
PeiDebugPrintHobLibConstructor (
  IN EFI_PEI_FILE_HANDLE        FileHandle,
  IN CONST EFI_PEI_SERVICES     **PeiServices
  )
{
  EFI_STATUS                      Status;
  EFI_PEI_READ_ONLY_VARIABLE2_PPI *Variable;
  UINTN                           Size;
  UINT64                          GlobalErrorLevel;
  UINT32                          HobErrorLevel;

  Status = PeiServicesLocatePpi (
             &gEfiPeiReadOnlyVariable2PpiGuid,
             0,
             NULL,
             (VOID **)&Variable
             );
  if (!EFI_ERROR (Status)) {
    Size = sizeof (GlobalErrorLevel);
    Status = Variable->GetVariable (
                         Variable,
                         DEBUG_MASK_VARIABLE_NAME,
                         &gEfiGenericVariableGuid,
                         NULL,
                         &Size,
                         &GlobalErrorLevel
                         );
    if (!EFI_ERROR (Status)) {
      //
      // Build the GUID'ed HOB for DXE
      //
      HobErrorLevel = (UINT32)GlobalErrorLevel;
      BuildGuidDataHob (
        &gEfiGenericVariableGuid,
        &HobErrorLevel,
        sizeof (HobErrorLevel)
        );
    }
  }

  return EFI_SUCCESS;
}