audk/UefiCpuPkg/CpuFeatures/CpuFeaturesDxe.c

/** @file
  CPU Features DXE driver to initialize CPU features.

  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include <PiDxe.h>

#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/RegisterCpuFeaturesLib.h>

#include <Protocol/SmmConfiguration.h>
#include <Guid/CpuFeaturesInitDone.h>


/**
  Worker function to perform CPU feature initialization.

**/
VOID
CpuFeaturesInitializeWorker (
  VOID
  )
{
  EFI_STATUS             Status;
  EFI_HANDLE             Handle;

  CpuFeaturesDetect ();

  CpuFeaturesInitialize ();

  //
  // Install CPU Features Init Done Protocol
  //
  Handle = NULL;
  Status = gBS->InstallProtocolInterface (
                  &Handle,
                  &gEdkiiCpuFeaturesInitDoneGuid,
                  EFI_NATIVE_INTERFACE,
                  NULL
                  );
  ASSERT_EFI_ERROR (Status);
}

/**
  Event notification that initialize CPU features when gEfiSmmConfigurationProtocol installs.

  @param[in]  Event                 The Event that is being processed, not used.
  @param[in]  Context               Event Context, not used.
**/
VOID
EFIAPI
SmmConfigurationEventNotify (
  IN EFI_EVENT                         Event,
  IN VOID                              *Context
  )
{
  EFI_STATUS                           Status;
  EFI_SMM_CONFIGURATION_PROTOCOL       *SmmConfiguration;

  //
  // Make sure this notification is for this handler
  //
  Status = gBS->LocateProtocol (&gEfiSmmConfigurationProtocolGuid, NULL, (VOID **)&SmmConfiguration);
  if (EFI_ERROR (Status)) {
    return;
  }

  CpuFeaturesInitializeWorker ();
}

/**
  CPU Features driver entry point function.

  If PcdCpuFeaturesInitAfterSmmRelocation is TRUE, it will register one
  SMM Configuration Protocol notify function to perform CPU features
  initialization. Otherwise, it will perform CPU features initialization
  directly.

  @param ImageHandle     Image handle this driver.
  @param SystemTable     Pointer to the System Table.

  @retval EFI_SUCCESS   CPU Features is initialized successfully.
**/
EFI_STATUS
EFIAPI
CpuFeaturesDxeInitialize (
  IN EFI_HANDLE                            ImageHandle,
  IN EFI_SYSTEM_TABLE                      *SystemTable
  )
{
  VOID        *Registration;

  if (PcdGetBool (PcdCpuFeaturesInitAfterSmmRelocation)) {
    //
    // Install notification callback on SMM Configuration Protocol
    //
    EfiCreateProtocolNotifyEvent (
      &gEfiSmmConfigurationProtocolGuid,
      TPL_CALLBACK,
      SmmConfigurationEventNotify,
      NULL,
      &Registration
      );
  } else {
    CpuFeaturesInitializeWorker ();
  }

  return EFI_SUCCESS;
}