/**@file | |
Install a callback when necessary for setting the Feature Control MSR on all | |
processors. | |
Copyright (C) 2016, Red Hat, Inc. | |
SPDX-License-Identifier: BSD-2-Clause-Patent | |
**/ | |
#include <Library/DebugLib.h> | |
#include <Library/HobLib.h> | |
#include <Library/PeiServicesLib.h> | |
#include <Library/QemuFwCfgLib.h> | |
#include <Ppi/MpServices.h> | |
#include <Register/ArchitecturalMsr.h> | |
#include <IndustryStandard/Tdx.h> | |
#include "Platform.h" | |
/** | |
Write the Feature Control MSR on an Application Processor or the Boot | |
Processor. | |
All APs execute this function in parallel. The BSP executes the function | |
separately. | |
@param[in,out] WorkSpace Pointer to the input/output argument workspace | |
shared by all processors. | |
**/ | |
STATIC | |
VOID | |
EFIAPI | |
WriteFeatureControl ( | |
IN OUT VOID *WorkSpace | |
) | |
{ | |
EFI_HOB_PLATFORM_INFO *PlatformInfoHob = WorkSpace; | |
if (TdIsEnabled ()) { | |
TdVmCall ( | |
TDVMCALL_WRMSR, | |
(UINT64)MSR_IA32_FEATURE_CONTROL, | |
PlatformInfoHob->FeatureControlValue, | |
0, | |
0, | |
0 | |
); | |
} else { | |
AsmWriteMsr64 ( | |
MSR_IA32_FEATURE_CONTROL, | |
PlatformInfoHob->FeatureControlValue | |
); | |
} | |
} | |
/** | |
Notification function called when EFI_PEI_MP_SERVICES_PPI becomes available. | |
@param[in] PeiServices Indirect reference to the PEI Services Table. | |
@param[in] NotifyDescriptor Address of the notification descriptor data | |
structure. | |
@param[in] Ppi Address of the PPI that was installed. | |
@return Status of the notification. The status code returned from this | |
function is ignored. | |
**/ | |
STATIC | |
EFI_STATUS | |
EFIAPI | |
OnMpServicesAvailable ( | |
IN EFI_PEI_SERVICES **PeiServices, | |
IN EFI_PEI_NOTIFY_DESCRIPTOR *NotifyDescriptor, | |
IN VOID *Ppi | |
) | |
{ | |
EFI_PEI_MP_SERVICES_PPI *MpServices; | |
EFI_STATUS Status; | |
EFI_HOB_PLATFORM_INFO *PlatformInfoHob; | |
EFI_HOB_GUID_TYPE *GuidHob; | |
GuidHob = GetFirstGuidHob (&gUefiOvmfPkgPlatformInfoGuid); | |
if (GuidHob == NULL) { | |
return EFI_UNSUPPORTED; | |
} | |
PlatformInfoHob = (EFI_HOB_PLATFORM_INFO *)GET_GUID_HOB_DATA (GuidHob); | |
DEBUG ((DEBUG_VERBOSE, "%a: %a\n", gEfiCallerBaseName, __func__)); | |
// | |
// Write the MSR on all the APs in parallel. | |
// | |
MpServices = Ppi; | |
Status = MpServices->StartupAllAPs ( | |
(CONST EFI_PEI_SERVICES **)PeiServices, | |
MpServices, | |
WriteFeatureControl, // Procedure | |
FALSE, // SingleThread | |
0, // TimeoutInMicroSeconds: inf. | |
PlatformInfoHob // ProcedureArgument | |
); | |
if (EFI_ERROR (Status) && (Status != EFI_NOT_STARTED)) { | |
DEBUG ((DEBUG_ERROR, "%a: StartupAllAps(): %r\n", __func__, Status)); | |
return Status; | |
} | |
// | |
// Now write the MSR on the BSP too. | |
// | |
WriteFeatureControl (PlatformInfoHob); | |
return EFI_SUCCESS; | |
} | |
// | |
// Notification object for registering the callback, for when | |
// EFI_PEI_MP_SERVICES_PPI becomes available. | |
// | |
STATIC CONST EFI_PEI_NOTIFY_DESCRIPTOR mMpServicesNotify = { | |
EFI_PEI_PPI_DESCRIPTOR_NOTIFY_CALLBACK | // Flags | |
EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST, | |
&gEfiPeiMpServicesPpiGuid, // Guid | |
OnMpServicesAvailable // Notify | |
}; | |
VOID | |
InstallFeatureControlCallback ( | |
IN OUT EFI_HOB_PLATFORM_INFO *PlatformInfoHob | |
) | |
{ | |
EFI_STATUS Status; | |
FIRMWARE_CONFIG_ITEM FwCfgItem; | |
UINTN FwCfgSize; | |
Status = QemuFwCfgFindFile ( | |
"etc/msr_feature_control", | |
&FwCfgItem, | |
&FwCfgSize | |
); | |
if (EFI_ERROR (Status) || (FwCfgSize != sizeof (PlatformInfoHob->FeatureControlValue))) { | |
// | |
// Nothing to do. | |
// | |
return; | |
} | |
QemuFwCfgSelectItem (FwCfgItem); | |
QemuFwCfgReadBytes ( | |
sizeof (PlatformInfoHob->FeatureControlValue), | |
&(PlatformInfoHob->FeatureControlValue) | |
); | |
Status = PeiServicesNotifyPpi (&mMpServicesNotify); | |
if (EFI_ERROR (Status)) { | |
DEBUG (( | |
DEBUG_ERROR, | |
"%a: failed to set up MP Services callback: %r\n", | |
__func__, | |
Status | |
)); | |
} | |
} |