ArmVirtPkg/KvmtoolPlatformDxe/KvmtoolPlatformDxe.c

   1 /** @file
   2
   3   The KvmtoolPlatformDxe performs the platform specific initialization like:
   4   - It decides if the firmware should expose ACPI or Device Tree-based
   5     hardware description to the operating system.
   6
   7   Copyright (c) 2018 - 2020, ARM Limited. All rights reserved.
   8
   9   SPDX-License-Identifier: BSD-2-Clause-Patent
  10
  11 **/
  12
  13 #include <Guid/VariableFormat.h>
  14 #include <Library/BaseLib.h>
  15 #include <Library/DebugLib.h>
  16 #include <Library/UefiBootServicesTableLib.h>
  17 #include <Protocol/FdtClient.h>
  18
  19 /** Decide if the firmware should expose ACPI tables or Device Tree and
  20     install the appropriate protocol interface.
  21
  22   Note: This function is derived from "ArmVirtPkg/PlatformHasAcpiDtDxe",
  23         by dropping the word size check, and the fw_cfg check.
  24
  25   @param [in]  ImageHandle  Handle for this image.
  26
  27   @retval EFI_SUCCESS             Success.
  28   @retval EFI_OUT_OF_RESOURCES    There was not enough memory to install the
  29                                   protocols.
  30   @retval EFI_INVALID_PARAMETER   A parameter is invalid.
  31
  32 **/
  33 STATIC
  34 EFI_STATUS
  35 PlatformHasAcpiDt (
  36   IN EFI_HANDLE           ImageHandle
  37   )
  38 {
  39   if (!PcdGetBool (PcdForceNoAcpi)) {
  40     // Expose ACPI tables
  41     return gBS->InstallProtocolInterface (
  42                   &ImageHandle,
  43                   &gEdkiiPlatformHasAcpiGuid,
  44                   EFI_NATIVE_INTERFACE,
  45                   NULL
  46                   );
  47   }
  48
  49   // Expose the Device Tree.
  50   return gBS->InstallProtocolInterface (
  51                 &ImageHandle,
  52                 &gEdkiiPlatformHasDeviceTreeGuid,
  53                 EFI_NATIVE_INTERFACE,
  54                 NULL
  55                 );
  56 }
  57
  58 /** Entry point for Kvmtool Platform Dxe
  59
  60   @param [in]  ImageHandle  Handle for this image.
  61   @param [in]  SystemTable  Pointer to the EFI system table.
  62
  63   @retval EFI_SUCCESS             Success.
  64   @retval EFI_OUT_OF_RESOURCES    There was not enough memory to install the
  65                                   protocols.
  66   @retval EFI_INVALID_PARAMETER   A parameter is invalid.
  67
  68 **/
  69 EFI_STATUS
  70 EFIAPI
  71 KvmtoolPlatformDxeEntryPoint (
  72   IN EFI_HANDLE           ImageHandle,
  73   IN EFI_SYSTEM_TABLE     *SystemTable
  74   )
  75 {
  76   EFI_STATUS                     Status;
  77
  78   Status = PlatformHasAcpiDt (ImageHandle);
  79   ASSERT_EFI_ERROR (Status);
  80
  81   return Status;
  82 }