ArmVirtPkg/PlatformHasAcpiDtDxe/PlatformHasAcpiDtDxe.c

   1 /** @file
   2   Decide whether the firmware should expose an ACPI- and/or a Device Tree-based
   3   hardware description to the operating system.
   4
   5   Copyright (c) 2017, Red Hat, Inc.
   6
   7   This program and the accompanying materials are licensed and made available
   8   under the terms and conditions of the BSD License which accompanies this
   9   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, WITHOUT
  13   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14 **/
  15
  16 #include <Guid/PlatformHasAcpi.h>
  17 #include <Guid/PlatformHasDeviceTree.h>
  18 #include <Library/BaseLib.h>
  19 #include <Library/DebugLib.h>
  20 #include <Library/PcdLib.h>
  21 #include <Library/UefiBootServicesTableLib.h>
  22
  23 EFI_STATUS
  24 EFIAPI
  25 PlatformHasAcpiDt (
  26   IN EFI_HANDLE       ImageHandle,
  27   IN EFI_SYSTEM_TABLE *SystemTable
  28   )
  29 {
  30   EFI_STATUS Status;
  31
  32   Status = EFI_SUCCESS;
  33
  34   //
  35   // If we fail to install any of the necessary protocols below, the OS will be
  36   // unbootable anyway (due to lacking hardware description), so tolerate no
  37   // errors here.
  38   //
  39   // Always make ACPI available on 64-bit systems.
  40   //
  41   if (MAX_UINTN == MAX_UINT64) {
  42     Status = gBS->InstallProtocolInterface (
  43                     &ImageHandle,
  44                     &gEdkiiPlatformHasAcpiGuid,
  45                     EFI_NATIVE_INTERFACE,
  46                     NULL
  47                     );
  48     if (EFI_ERROR (Status)) {
  49       goto Failed;
  50     }
  51   }
  52
  53   //
  54   // Expose the Device Tree unless PcdPureAcpiBoot is set.
  55   //
  56   if (!FeaturePcdGet (PcdPureAcpiBoot)) {
  57     Status = gBS->InstallProtocolInterface (
  58                     &ImageHandle,
  59                     &gEdkiiPlatformHasDeviceTreeGuid,
  60                     EFI_NATIVE_INTERFACE,
  61                     NULL
  62                     );
  63     if (EFI_ERROR (Status)) {
  64       goto Failed;
  65     }
  66   }
  67
  68   return Status;
  69
  70 Failed:
  71   ASSERT_EFI_ERROR (Status);
  72   CpuDeadLoop ();
  73   //
  74   // Keep compilers happy.
  75   //
  76   return Status;
  77 }