| /** @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; | |
| } |