audk/OvmfPkg/PlatformHasAcpiDtDxe/PlatformHasAcpiDtDxe.c

84 lines
2.0 KiB
C

/** @file
Decide whether the firmware should expose an ACPI- and/or a Device Tree-based
hardware description to the operating system.
Copyright (c) 2017, Red Hat, Inc.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Guid/PlatformHasAcpi.h>
#include <Guid/PlatformHasDeviceTree.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/PcdLib.h>
#include <Library/QemuFwCfgLib.h>
#include <Library/UefiBootServicesTableLib.h>
EFI_STATUS
EFIAPI
PlatformHasAcpiDt (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
FIRMWARE_CONFIG_ITEM FwCfgItem;
UINTN FwCfgSize;
//
// 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) &&
!EFI_ERROR (
QemuFwCfgFindFile (
"etc/table-loader",
&FwCfgItem,
&FwCfgSize
)
))
{
//
// Only make ACPI available on 64-bit systems, and only if QEMU generates
// (a subset of) the ACPI tables.
//
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;
}