audk/OvmfPkg/PlatformPei/FeatureControl.c

129 lines
3.6 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/PeiServicesLib.h>
#include <Library/QemuFwCfgLib.h>
#include <Ppi/MpServices.h>
#include <Register/Msr/Core2Msr.h>
#include "Platform.h"
//
// The value to be written to the Feature Control MSR, retrieved from fw_cfg.
//
STATIC UINT64 mFeatureControlValue;
/**
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
)
{
AsmWriteMsr64 (MSR_CORE2_FEATURE_CONTROL, mFeatureControlValue);
}
/**
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;
DEBUG ((EFI_D_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.
NULL // ProcedureArgument
);
if (EFI_ERROR (Status) && Status != EFI_NOT_STARTED) {
DEBUG ((EFI_D_ERROR, "%a: StartupAllAps(): %r\n", __FUNCTION__, Status));
return Status;
}
//
// Now write the MSR on the BSP too.
//
WriteFeatureControl (NULL);
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 (
VOID
)
{
EFI_STATUS Status;
FIRMWARE_CONFIG_ITEM FwCfgItem;
UINTN FwCfgSize;
Status = QemuFwCfgFindFile ("etc/msr_feature_control", &FwCfgItem,
&FwCfgSize);
if (EFI_ERROR (Status) || FwCfgSize != sizeof mFeatureControlValue) {
//
// Nothing to do.
//
return;
}
QemuFwCfgSelectItem (FwCfgItem);
QemuFwCfgReadBytes (sizeof mFeatureControlValue, &mFeatureControlValue);
Status = PeiServicesNotifyPpi (&mMpServicesNotify);
if (EFI_ERROR (Status)) {
DEBUG ((EFI_D_ERROR, "%a: failed to set up MP Services callback: %r\n",
__FUNCTION__, Status));
}
}