/** @file
Decide whether the firmware should expose an ACPI- and/or a Device Tree-based
hardware description to the operating system.
Copyright (c) 2021, Arm Limited. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include
#include
#include
#include
#include
#include
/** Entry point for the Cloud Hypervisor PlatformHasAcpiDtDxe.
@param [in] ImageHandle Handle for this image.
@param [in] SystemTable Pointer to the EFI system table.
@return EFI_SUCCESS If ACPI or Device Tree based hardware
description protocol was installed.
@return EFI_INVALID_PARAMETER A parameter was invalid.
@return EFI_OUT_OF_RESOURCES Insufficient resources exist to complete
the request.
**/
EFI_STATUS
EFIAPI
PlatformHasAcpiDt (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
//
// If we fail to install any of the necessary protocols below, the OS will be
// unbootable anyway (due to lacking hardware description), so tolerate no
// errors here.
//
if ((MAX_UINTN == MAX_UINT64) &&
!PcdGetBool (PcdForceNoAcpi))
{
Status = gBS->InstallProtocolInterface (
&ImageHandle,
&gEdkiiPlatformHasAcpiGuid,
EFI_NATIVE_INTERFACE,
NULL
);
if (EFI_ERROR (Status)) {
goto Failed;
}
return Status;
}
//
// Expose the Device Tree otherwise.
//
Status = gBS->InstallProtocolInterface (
&ImageHandle,
&gEdkiiPlatformHasDeviceTreeGuid,
EFI_NATIVE_INTERFACE,
NULL
);
if (EFI_ERROR (Status)) {
goto Failed;
}
return Status;
Failed:
ASSERT_EFI_ERROR (Status);
CpuDeadLoop ();
//
// Keep compilers happy.
//
return Status;
}