#include "MpLib.h"
#include <Library/UefiLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/DebugAgentLib.h>
#include <Library/DxeServicesTableLib.h>
#include <Library/CcExitLib.h>
#include <Register/Amd/SevSnpMsr.h>
#include <Register/Amd/Ghcb.h>
#include <Protocol/Timer.h>

Macros
#define	AP_SAFE_STACK_SIZE 128

Functions
VOID	EnableDebugAgent (VOID)

CPU_MP_DATA *	GetCpuMpData (VOID)

VOID	SaveCpuMpData (IN CPU_MP_DATA *CpuMpData)

UINTN	GetWakeupBuffer (IN UINTN WakeupBufferSize)

UINTN	AllocateCodeBuffer (IN UINTN BufferSize)

UINTN	GetSevEsAPMemory (VOID)

VOID	CheckAndUpdateApsStatus (VOID)

VOID EFIAPI	CheckApsStatus (IN EFI_EVENT Event, IN VOID *Context)

UINT16	GetProtectedMode16CS (VOID)

UINT16	GetProtectedModeCS (VOID)

VOID	AllocateApLoopCodeBuffer (IN UINTN Pages, IN OUT EFI_PHYSICAL_ADDRESS *Address)

VOID	RemoveNxprotection (IN EFI_PHYSICAL_ADDRESS BaseAddress, IN UINTN Length)

VOID EFIAPI	MpInitChangeApLoopCallback (IN EFI_EVENT Event, IN VOID *Context)

VOID	InitMpGlobalData (IN CPU_MP_DATA *CpuMpData)

EFI_STATUS EFIAPI	MpInitLibStartupAllAPs (IN EFI_AP_PROCEDURE Procedure, IN BOOLEAN SingleThread, IN EFI_EVENT WaitEvent OPTIONAL, IN UINTN TimeoutInMicroseconds, IN VOID ProcedureArgument OPTIONAL, OUT UINTN *FailedCpuList OPTIONAL)

EFI_STATUS EFIAPI	MpInitLibStartupThisAP (IN EFI_AP_PROCEDURE Procedure, IN UINTN ProcessorNumber, IN EFI_EVENT WaitEvent OPTIONAL, IN UINTN TimeoutInMicroseconds, IN VOID ProcedureArgument OPTIONAL, OUT BOOLEAN Finished OPTIONAL)

EFI_STATUS EFIAPI	MpInitLibSwitchBSP (IN UINTN ProcessorNumber, IN BOOLEAN EnableOldBSP)

EFI_STATUS EFIAPI	MpInitLibEnableDisableAP (IN UINTN ProcessorNumber, IN BOOLEAN EnableAP, IN UINT32 *HealthFlag OPTIONAL)

EFI_STATUS	PlatformShadowMicrocode (IN OUT CPU_MP_DATA *CpuMpData)

Variables
CPU_MP_DATA *	mCpuMpData = NULL

EFI_EVENT	mCheckAllApsEvent = NULL

EFI_EVENT	mMpInitExitBootServicesEvent = NULL

EFI_EVENT	mLegacyBootEvent = NULL

volatile BOOLEAN	mStopCheckAllApsStatus = TRUE

STATIC EFI_PHYSICAL_ADDRESS	mSevEsDxeWakeupBuffer = 0x88000

Detailed Description

MP initialize support functions for DXE phase.

Copyright (c) 2016 - 2024, Intel Corporation. All rights reserved.
Copyright (c) 2024, AMD Inc. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file DxeMpLib.c.

Macro Definition Documentation

◆ AP_SAFE_STACK_SIZE

#define AP_SAFE_STACK_SIZE 128

Definition at line 22 of file DxeMpLib.c.

Function Documentation

◆ AllocateApLoopCodeBuffer()

VOID AllocateApLoopCodeBuffer	(	IN UINTN	Pages,
		IN OUT EFI_PHYSICAL_ADDRESS *	Address
	)

Allocate buffer for ApLoopCode.

Parameters

[in]	Pages	Number of pages to allocate.
[in,out]	Address	Pointer to the allocated buffer.

Definition at line 401 of file DxeMpLib.c.

◆ AllocateCodeBuffer()

UINTN AllocateCodeBuffer ( IN UINTN BufferSize )

Get available EfiBootServicesCode memory below 4GB by specified size.

This buffer is required to safely transfer AP from real address mode to protected mode or long mode, due to the fact that the buffer returned by GetWakeupBuffer() may be marked as non-executable.

Parameters

[in] BufferSize Wakeup transition buffer size.

Return values

other	Return wakeup transition buffer address below 4GB.
0	Cannot find free memory below 4GB.

Definition at line 163 of file DxeMpLib.c.

◆ CheckAndUpdateApsStatus()

VOID CheckAndUpdateApsStatus ( VOID )

Checks APs status and updates APs status if needed.

Definition at line 235 of file DxeMpLib.c.

◆ CheckApsStatus()

VOID EFIAPI CheckApsStatus	(	IN EFI_EVENT	Event,
		IN VOID *	Context
	)

Checks APs' status periodically.

This function is triggered by timer periodically to check the state of APs for StartupAllAPs() and StartupThisAP() executed in non-blocking mode.

Parameters

[in]	Event	Event triggered.
[in]	Context	Parameter passed with the event.

Definition at line 289 of file DxeMpLib.c.

◆ EnableDebugAgent()

VOID EnableDebugAgent ( VOID )

Enable Debug Agent to support source debugging on AP function.

Definition at line 40 of file DxeMpLib.c.

◆ GetCpuMpData()

CPU_MP_DATA * GetCpuMpData ( VOID )

Get the pointer to CPU MP Data structure.

Returns: The pointer to CPU MP Data structure.

Definition at line 56 of file DxeMpLib.c.

◆ GetProtectedMode16CS()

UINT16 GetProtectedMode16CS ( VOID )

Get Protected mode code segment with 16-bit default addressing from current GDT table.

Returns: Protected mode 16-bit code segment value.

Definition at line 309 of file DxeMpLib.c.

◆ GetProtectedModeCS()

UINT16 GetProtectedModeCS ( VOID )

Get Protected mode code segment from current GDT table.

Returns: Protected mode code segment value.

Definition at line 355 of file DxeMpLib.c.

◆ GetSevEsAPMemory()

UINTN GetSevEsAPMemory ( VOID )

Return the address of the SEV-ES AP jump table.

This buffer is required in order for an SEV-ES guest to transition from UEFI into an OS.

Returns: Return SEV-ES AP jump table buffer

Definition at line 193 of file DxeMpLib.c.

◆ GetWakeupBuffer()

UINTN GetWakeupBuffer ( IN UINTN WakeupBufferSize )

Get available system memory below 0x88000 by specified size.

Parameters

[in] WakeupBufferSize Wakeup buffer size required

Return values

other	Return wakeup buffer address below 1MB.
-1	Cannot find free memory below 1MB.

Definition at line 86 of file DxeMpLib.c.

◆ InitMpGlobalData()

VOID InitMpGlobalData ( IN CPU_MP_DATA * CpuMpData )

Initialize global data for MP support.

Parameters

[in] CpuMpData The pointer to CPU MP Data structure.

Definition at line 499 of file DxeMpLib.c.

◆ MpInitChangeApLoopCallback()

VOID EFIAPI MpInitChangeApLoopCallback	(	IN EFI_EVENT	Event,
		IN VOID *	Context
	)

Callback function for ExitBootServices.

Parameters

[in]	Event	Event whose notification function is being invoked.
[in]	Context	The pointer to the notification function's context, which is implementation-dependent.

Definition at line 459 of file DxeMpLib.c.

◆ MpInitLibEnableDisableAP()

EFI_STATUS EFIAPI MpInitLibEnableDisableAP	(	IN UINTN	ProcessorNumber,
		IN BOOLEAN	EnableAP,
		IN UINT32 *HealthFlag	OPTIONAL
	)

This service lets the caller enable or disable an AP from this point onward. This service may only be called from the BSP.

Parameters

[in]	ProcessorNumber	The handle number of AP. The range is from 0 to the total number of logical processors minus 1. The total number of logical processors can be retrieved by MpInitLibGetNumberOfProcessors().
[in]	EnableAP	Specifies the new state for the processor for enabled, FALSE for disabled.
[in]	HealthFlag	If not NULL, a pointer to a value that specifies the new health status of the AP. This flag corresponds to StatusFlag defined in EFI_MP_SERVICES_PROTOCOL.GetProcessorInfo(). Only the PROCESSOR_HEALTH_STATUS_BIT is used. All other bits are ignored. If it is NULL, this parameter is ignored.

Return values

EFI_SUCCESS	The specified AP was enabled or disabled successfully.
EFI_UNSUPPORTED	Enabling or disabling an AP cannot be completed prior to this service returning.
EFI_UNSUPPORTED	Enabling or disabling an AP is not supported.
EFI_DEVICE_ERROR	The calling processor is an AP.
EFI_NOT_FOUND	Processor with the handle specified by ProcessorNumber does not exist.
EFI_INVALID_PARAMETER	ProcessorNumber specifies the BSP.
EFI_NOT_READY	MP Initialize Library is not initialized.

Definition at line 920 of file DxeMpLib.c.

◆ MpInitLibStartupAllAPs()

EFI_STATUS EFIAPI MpInitLibStartupAllAPs	(	IN EFI_AP_PROCEDURE	Procedure,
		IN BOOLEAN	SingleThread,
		IN EFI_EVENT WaitEvent	OPTIONAL,
		IN UINTN	TimeoutInMicroseconds,
		IN VOID *ProcedureArgument	OPTIONAL,
		OUT UINTN **FailedCpuList	OPTIONAL
	)

This service executes a caller provided function on all enabled APs.

Parameters

[in]	Procedure	A pointer to the function to be run on enabled APs of the system. See type EFI_AP_PROCEDURE.
[in]	SingleThread	If TRUE, then all the enabled APs execute the function specified by Procedure one by one, in ascending order of processor handle number. If FALSE, then all the enabled APs execute the function specified by Procedure simultaneously.
[in]	WaitEvent	The event created by the caller with CreateEvent() service. If it is NULL, then execute in blocking mode. BSP waits until all APs finish or TimeoutInMicroSeconds expires. If it's not NULL, then execute in non-blocking mode. BSP requests the function specified by Procedure to be started on all the enabled APs, and go on executing immediately. If all return from Procedure, or TimeoutInMicroSeconds expires, this event is signaled. The BSP can use the CheckEvent() or WaitForEvent() services to check the state of event. Type EFI_EVENT is defined in CreateEvent() in the Unified Extensible Firmware Interface Specification.
[in]	TimeoutInMicroseconds	Indicates the time limit in microseconds for APs to return from Procedure, either for blocking or non-blocking mode. Zero means infinity. If the timeout expires before all APs return from Procedure, then Procedure on the failed APs is terminated. All enabled APs are available for next function assigned by MpInitLibStartupAllAPs() or MPInitLibStartupThisAP(). If the timeout expires in blocking mode, BSP returns EFI_TIMEOUT. If the timeout expires in non-blocking mode, WaitEvent is signaled with SignalEvent().
[in]	ProcedureArgument	The parameter passed into Procedure for all APs.
[out]	FailedCpuList	If NULL, this parameter is ignored. Otherwise, if all APs finish successfully, then its content is set to NULL. If not all APs finish before timeout expires, then its content is set to address of the buffer holding handle numbers of the failed APs. The buffer is allocated by MP Initialization library, and it's the caller's responsibility to free the buffer with FreePool() service. In blocking mode, it is ready for consumption when the call returns. In non-blocking mode, it is ready when WaitEvent is signaled. The list of failed CPU is terminated by END_OF_CPU_LIST.

Return values

EFI_SUCCESS	In blocking mode, all APs have finished before the timeout expired.
EFI_SUCCESS	In non-blocking mode, function has been dispatched to all enabled APs.
EFI_UNSUPPORTED	A non-blocking mode request was made after the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was signaled.
EFI_UNSUPPORTED	WaitEvent is not NULL if non-blocking mode is not supported.
EFI_DEVICE_ERROR	Caller processor is AP.
EFI_NOT_STARTED	No enabled APs exist in the system.
EFI_NOT_READY	Any enabled APs are busy.
EFI_NOT_READY	MP Initialize Library is not initialized.
EFI_TIMEOUT	In blocking mode, the timeout expired before all enabled APs have finished.
EFI_INVALID_PARAMETER	Procedure is NULL.

Definition at line 682 of file DxeMpLib.c.

◆ MpInitLibStartupThisAP()

EFI_STATUS EFIAPI MpInitLibStartupThisAP	(	IN EFI_AP_PROCEDURE	Procedure,
		IN UINTN	ProcessorNumber,
		IN EFI_EVENT WaitEvent	OPTIONAL,
		IN UINTN	TimeoutInMicroseconds,
		IN VOID *ProcedureArgument	OPTIONAL,
		OUT BOOLEAN *Finished	OPTIONAL
	)

This service lets the caller get one enabled AP to execute a caller-provided function.

Parameters

[in]	Procedure	A pointer to the function to be run on the designated AP of the system. See type EFI_AP_PROCEDURE.
[in]	ProcessorNumber	The handle number of the AP. The range is from 0 to the total number of logical processors minus 1. The total number of logical processors can be retrieved by MpInitLibGetNumberOfProcessors().
[in]	WaitEvent	The event created by the caller with CreateEvent() service. If it is NULL, then execute in blocking mode. BSP waits until this AP finish or TimeoutInMicroSeconds expires. If it's not NULL, then execute in non-blocking mode. BSP requests the function specified by Procedure to be started on this AP, and go on executing immediately. If this AP return from Procedure or TimeoutInMicroSeconds expires, this event is signaled. The BSP can use the CheckEvent() or WaitForEvent() services to check the state of event. Type EFI_EVENT is defined in CreateEvent() in the Unified Extensible Firmware Interface Specification.
[in]	TimeoutInMicroseconds	Indicates the time limit in microseconds for this AP to finish this Procedure, either for blocking or non-blocking mode. Zero means infinity. If the timeout expires before this AP returns from Procedure, then Procedure on the AP is terminated. The AP is available for next function assigned by MpInitLibStartupAllAPs() or MpInitLibStartupThisAP(). If the timeout expires in blocking mode, BSP returns EFI_TIMEOUT. If the timeout expires in non-blocking mode, WaitEvent is signaled with SignalEvent().
[in]	ProcedureArgument	The parameter passed into Procedure on the specified AP.
[out]	Finished	If NULL, this parameter is ignored. In blocking mode, this parameter is ignored. In non-blocking mode, if AP returns from Procedure before the timeout expires, its content is set to TRUE. Otherwise, the value is set to FALSE. The caller can determine if the AP returned from Procedure by evaluating this value.

Return values

EFI_SUCCESS	In blocking mode, specified AP finished before the timeout expires.
EFI_SUCCESS	In non-blocking mode, the function has been dispatched to specified AP.
EFI_UNSUPPORTED	A non-blocking mode request was made after the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was signaled.
EFI_UNSUPPORTED	WaitEvent is not NULL if non-blocking mode is not supported.
EFI_DEVICE_ERROR	The calling processor is an AP.
EFI_TIMEOUT	In blocking mode, the timeout expired before the specified AP has finished.
EFI_NOT_READY	The specified AP is busy.
EFI_NOT_READY	MP Initialize Library is not initialized.
EFI_NOT_FOUND	The processor with the handle specified by ProcessorNumber does not exist.
EFI_INVALID_PARAMETER	ProcessorNumber specifies the BSP or disabled AP.
EFI_INVALID_PARAMETER	Procedure is NULL.

Definition at line 789 of file DxeMpLib.c.

◆ MpInitLibSwitchBSP()

EFI_STATUS EFIAPI MpInitLibSwitchBSP	(	IN UINTN	ProcessorNumber,
		IN BOOLEAN	EnableOldBSP
	)

This service switches the requested AP to be the BSP from that point onward. This service changes the BSP for all purposes. This call can only be performed by the current BSP.

Parameters

[in]	ProcessorNumber	The handle number of AP that is to become the new BSP. The range is from 0 to the total number of logical processors minus 1. The total number of logical processors can be retrieved by MpInitLibGetNumberOfProcessors().
[in]	EnableOldBSP	If TRUE, then the old BSP will be listed as an enabled AP. Otherwise, it will be disabled.

Return values

EFI_SUCCESS	BSP successfully switched.
EFI_UNSUPPORTED	Switching the BSP cannot be completed prior to this service returning.
EFI_UNSUPPORTED	Switching the BSP is not supported.
EFI_DEVICE_ERROR	The calling processor is an AP.
EFI_NOT_FOUND	The processor with the handle specified by ProcessorNumber does not exist.
EFI_INVALID_PARAMETER	ProcessorNumber specifies the current BSP or a disabled AP.
EFI_NOT_READY	The specified AP is busy.
EFI_NOT_READY	MP Initialize Library is not initialized.

Definition at line 847 of file DxeMpLib.c.

◆ PlatformShadowMicrocode()

EFI_STATUS PlatformShadowMicrocode ( IN OUT CPU_MP_DATA * CpuMpData )

This funtion will try to invoke platform specific microcode shadow logic to relocate microcode update patches into memory.

Parameters

[in,out] CpuMpData The pointer to CPU MP Data structure.

Return values

EFI_SUCCESS	Shadow microcode success.
EFI_OUT_OF_RESOURCES	No enough resource to complete the operation.
EFI_UNSUPPORTED	Can't find platform specific microcode shadow PPI/Protocol.

Definition at line 959 of file DxeMpLib.c.

◆ RemoveNxprotection()

VOID RemoveNxprotection	(	IN EFI_PHYSICAL_ADDRESS	BaseAddress,
		IN UINTN	Length
	)

Remove Nx protection for the range specific by BaseAddress and Length.

The PEI implementation uses CpuPageTableLib to change the attribute. The DXE implementation uses gDS to change the attribute.

Parameters

[in]	BaseAddress	BaseAddress of the range.
[in]	Length	Length of the range.

Definition at line 427 of file DxeMpLib.c.

◆ SaveCpuMpData()

VOID SaveCpuMpData ( IN CPU_MP_DATA * CpuMpData )

Save the pointer to CPU MP Data structure.

Parameters

[in] CpuMpData The pointer to CPU MP Data structure will be saved.

Definition at line 70 of file DxeMpLib.c.

Variable Documentation

◆ mCheckAllApsEvent

EFI_EVENT mCheckAllApsEvent = NULL

Definition at line 25 of file DxeMpLib.c.

◆ mCpuMpData

CPU_MP_DATA* mCpuMpData = NULL

Definition at line 24 of file DxeMpLib.c.

◆ mLegacyBootEvent

EFI_EVENT mLegacyBootEvent = NULL

Definition at line 27 of file DxeMpLib.c.

◆ mMpInitExitBootServicesEvent

EFI_EVENT mMpInitExitBootServicesEvent = NULL

Definition at line 26 of file DxeMpLib.c.

◆ mSevEsDxeWakeupBuffer

STATIC EFI_PHYSICAL_ADDRESS mSevEsDxeWakeupBuffer = 0x88000

Definition at line 33 of file DxeMpLib.c.

◆ mStopCheckAllApsStatus

volatile BOOLEAN mStopCheckAllApsStatus = TRUE

Definition at line 28 of file DxeMpLib.c.

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ AP_SAFE_STACK_SIZE

Function Documentation

◆ AllocateApLoopCodeBuffer()

◆ AllocateCodeBuffer()

◆ CheckAndUpdateApsStatus()

◆ CheckApsStatus()

◆ EnableDebugAgent()

◆ GetCpuMpData()

◆ GetProtectedMode16CS()

◆ GetProtectedModeCS()

◆ GetSevEsAPMemory()

◆ GetWakeupBuffer()

◆ InitMpGlobalData()

◆ MpInitChangeApLoopCallback()

◆ MpInitLibEnableDisableAP()

◆ MpInitLibStartupAllAPs()

◆ MpInitLibStartupThisAP()

◆ MpInitLibSwitchBSP()

◆ PlatformShadowMicrocode()

◆ RemoveNxprotection()

◆ SaveCpuMpData()

Variable Documentation

◆ mCheckAllApsEvent

◆ mCpuMpData

◆ mLegacyBootEvent

◆ mMpInitExitBootServicesEvent

◆ mSevEsDxeWakeupBuffer

◆ mStopCheckAllApsStatus