audk/OvmfPkg/PlatformPei/FeatureControl.c

162 lines
4.4 KiB
C

/**@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, __FUNCTION__));
//
// 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", __FUNCTION__, 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",
__FUNCTION__,
Status
));
}
}