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/** @file
  Definitions for the PI MP Services Protocol defined in the PI spec.

@copyright
  Copyright (c) 2011 - 2012 Intel Corporation. All rights reserved
  This software and associated documentation (if any) is furnished
  under a license and may only be used or copied in accordance
  with the terms of the license. Except as permitted by such
  license, no part of this software or documentation may be
  reproduced, stored in a retrieval system, or transmitted in any
  form or by any means without the express written consent of
  Intel Corporation.

  This file contains 'Framework Code' and is licensed as such
  under the terms of your license agreement with Intel or your
  vendor.  This file may not be modified, except as allowed by
  additional terms of your license agreement.

**/
#ifndef _PI_MP_SERVICES_H_
#define _PI_MP_SERVICES_H_

///
/// Share some definitions from Framework MP Services Protocol
///
#include EFI_PROTOCOL_CONSUMER (MpService)

///
/// Global ID for the EFI_PI_MP_SERVICES_PROTOCOL.
///
#define EFI_PI_MP_SERVICES_PROTOCOL_GUID \
  { \
    0x3fdda605, 0xa76e, 0x4f46, \
    { \
      0xad, 0x29, 0x12, 0xf4, 0x53, 0x1b, 0x3d, 0x08 \
    } \
  }

///
/// Forward declaration for the EFI_PI_MP_SERVICES_PROTOCOL.
///
typedef struct _EFI_PI_MP_SERVICES_PROTOCOL EFI_PI_MP_SERVICES_PROTOCOL;

///
/// Terminator for a list of failed CPUs returned by StartAllAPs().
///
#define END_OF_CPU_LIST 0xffffffff

///
/// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
/// indicates whether the processor is playing the role of BSP. If the bit is 1,
/// then the processor is BSP. Otherwise, it is AP.
///
#define PROCESSOR_AS_BSP_BIT  0x00000001

///
/// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
/// indicates whether the processor is enabled. If the bit is 1, then the
/// processor is enabled. Otherwise, it is disabled.
///
#define PROCESSOR_ENABLED_BIT 0x00000002

///
/// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
/// indicates whether the processor is healthy. If the bit is 1, then the
/// processor is healthy. Otherwise, some fault has been detected for the processor.
///
#define PROCESSOR_HEALTH_STATUS_BIT 0x00000004

///
/// Structure that describes the pyhiscal location of a logical CPU.
///
typedef struct {
  ///
  /// Zero-based physical package number that identifies the cartridge of the processor.
  ///
  UINT32 Package;
  ///
  /// Zero-based physical core number within package of the processor.
  ///
  UINT32 Core;
  ///
  /// Zero-based logical thread number within core of the processor.
  ///
  UINT32 Thread;
} EFI_CPU_PHYSICAL_LOCATION;

///
/// Structure that describes information about a logical CPU.
///
typedef struct {
  ///
  /// The unique processor ID determined by system hardware.  For IA32 and X64,
  /// the processor ID is the same as the Local APIC ID. Only the lower 8 bits
  /// are used, and higher bits are reserved.  For IPF, the lower 16 bits contains
  /// id/eid, and higher bits are reserved.
  ///
  UINT64 ProcessorId;
  ///
  /// Flags indicating if the processor is BSP or AP, if the processor is enabled
  /// or disabled, and if the processor is healthy. Bits 3..31 are reserved and
  /// must be 0.
  ///
  /// <pre>
  /// BSP  ENABLED  HEALTH  Description
  /// ===  =======  ======  ===================================================
  ///  0      0       0     Unhealthy Disabled AP.
  ///  0      0       1     Healthy Disabled AP.
  ///  0      1       0     Unhealthy Enabled AP.
  ///  0      1       1     Healthy Enabled AP.
  ///  1      0       0     Invalid. The BSP can never be in the disabled state.
  ///  1      0       1     Invalid. The BSP can never be in the disabled state.
  ///  1      1       0     Unhealthy Enabled BSP.
  ///  1      1       1     Healthy Enabled BSP.
  /// </pre>
  ///
  UINT32 StatusFlag;
  ///
  /// The physical location of the processor, including the physical package number
  /// that identifies the cartridge, the physical core number within package, and
  /// logical thread number within core.
  ///
  EFI_CPU_PHYSICAL_LOCATION Location;
} EFI_PROCESSOR_INFORMATION;

/**
  This service retrieves the number of logical processor in the platform
  and the number of those logical processors that are enabled on this boot.
  This service may only be called from the BSP.

  This function is used to retrieve the following information:
    - The number of logical processors that are present in the system.
    - The number of enabled logical processors in the system at the instant
      this call is made.

  Because MP Service Protocol provides services to enable and disable processors
  dynamically, the number of enabled logical processors may vary during the
  course of a boot session.

  If this service is called from an AP, then EFI_DEVICE_ERROR is returned.
  If NumberOfProcessors or NumberOfEnabledProcessors is NULL, then
  EFI_INVALID_PARAMETER is returned. Otherwise, the total number of processors
  is returned in NumberOfProcessors, the number of currently enabled processor
  is returned in NumberOfEnabledProcessors, and EFI_SUCCESS is returned.

  @param[in] This                      - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] NumberOfProcessors        - Pointer to the total number of logical processors in the system,
                                         including the BSP and disabled APs.
  @param[in] NumberOfEnabledProcessors - Pointer to the number of enabled logical processors that exist
                                         in system, including the BSP.

  @retval EFI_SUCCESS            - Number of logical processors and enabled logical processors retrieved.
  @retval EFI_DEVICE_ERROR       - Caller processor is AP.
  @retval EFI_INVALID_PARAMETER  - NumberOfProcessors is NULL.
  @retval EFI_INVALID_PARAMETER  - NumberOfEnabledProcessors is NULL.
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  OUT UINTN                      *NumberOfProcessors,
  OUT UINTN                      *NumberOfEnabledProcessors
  );

/**
  Gets detailed MP-related information on the requested processor at the
  instant this call is made. This service may only be called from the BSP.

  This service retrieves detailed MP-related information about any processor
  on the platform. Note the following:
    - The processor information may change during the course of a boot session.
    - The information presented here is entirely MP related.

  Information regarding the number of caches and their sizes, frequency of operation,
  slot numbers is all considered platform-related information and is not provided
  by this service.

  @param[in] This                - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] ProcessorNumber     -  The handle number of processor.
  @param[in] ProcessorInfoBuffer - A pointer to the buffer where information for the requested processor is deposited.

  @retval EFI_SUCCESS           - Processor information successfully returned.
  @retval EFI_DEVICE_ERROR      - Caller processor is AP.
  @retval EFI_INVALID_PARAMETER - ProcessorInfoBuffer is NULL
  @retval EFI_NOT_FOUND         - Processor with the handle specified by ProcessorNumber does not exist.
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_GET_PROCESSOR_INFO)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  IN UINTN                       ProcessorNumber,
  OUT EFI_PROCESSOR_INFORMATION  *ProcessorInfoBuffer
  );

/**
  This service executes a caller provided function on all enabled APs. APs can
  run either simultaneously or one at a time in sequence. This service supports
  both blocking and non-blocking requests. The non-blocking requests use EFI
  events so the BSP can detect when the APs have finished. This service may only
  be called from the BSP.

  This function is used to dispatch all the enabled APs to the function specified
  by Procedure.  If any enabled AP is busy, then EFI_NOT_READY is returned
  immediately and Procedure is not started on any AP.

  If SingleThread is TRUE, all the enabled APs execute the function specified by
  Procedure one by one, in ascending order of processor handle number. Otherwise,
  all the enabled APs execute the function specified by Procedure simultaneously.

  If WaitEvent is NULL, execution is in blocking mode. The BSP waits until all
  APs finish or TimeoutInMicroSecs expires. Otherwise, execution is in non-blocking
  mode, and the BSP returns from this service without waiting for APs. If a
  non-blocking mode is requested after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
  is signaled, then EFI_UNSUPPORTED must be returned.

  If the timeout specified by TimeoutInMicroseconds expires before all APs return
  from Procedure, then Procedure on the failed APs is terminated. All enabled APs
  are always available for further calls to EFI_PI_MP_SERVICES_PROTOCOL.StartupAllAPs()
  and EFI_PI_MP_SERVICES_PROTOCOL.StartupThisAP(). If FailedCpuList is not NULL, its
  content points to the list of processor handle numbers in which Procedure was
  terminated.

  Note: It is the responsibility of the consumer of the EFI_PI_MP_SERVICES_PROTOCOL.StartupAllAPs()
  to make sure that the nature of the code that is executed on the BSP and the
  dispatched APs is well controlled. The MP Services Protocol does not guarantee
  that the Procedure function is MP-safe. Hence, the tasks that can be run in
  parallel are limited to certain independent tasks and well-controlled exclusive
  code. EFI services and protocols may not be called by APs unless otherwise
  specified.

  In blocking execution mode, BSP waits until all APs finish or
  TimeoutInMicroSeconds expires.

  In non-blocking execution mode, BSP is freed to return to the caller and then
  proceed to the next task without having to wait for APs. The following
  sequence needs to occur in a non-blocking execution mode:

    -# The caller that intends to use this MP Services Protocol in non-blocking
       mode creates WaitEvent by calling the EFI CreateEvent() service.  The caller
       invokes EFI_PI_MP_SERVICES_PROTOCOL.StartupAllAPs(). If the parameter WaitEvent
       is not NULL, then StartupAllAPs() executes in non-blocking mode. It requests
       the function specified by Procedure to be started on all the enabled APs,
       and releases the BSP to continue with other tasks.
    -# The caller can use the CheckEvent() and WaitForEvent() services to check
       the state of the WaitEvent created in step 1.
    -# When the APs complete their task or TimeoutInMicroSecondss expires, the MP
       Service signals WaitEvent by calling the EFI SignalEvent() function. If
       FailedCpuList is not NULL, its content is available when WaitEvent is
       signaled. If all APs returned from Procedure prior to the timeout, then
       FailedCpuList is set to NULL. If not all APs return from Procedure before
       the timeout, then FailedCpuList is filled in with the list of the failed
       APs. The buffer is allocated by MP Service Protocol using AllocatePool().
       It is the caller's responsibility to free the buffer with FreePool() service.
    -# This invocation of SignalEvent() function informs the caller that invoked
       EFI_PI_MP_SERVICES_PROTOCOL.StartupAllAPs() that either all the APs completed
       the specified task or a timeout occurred. The contents of FailedCpuList
       can be examined to determine which APs did not complete the specified task
       prior to the timeout.

  @param[in] This                  - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] Procedure             - A pointer to the function to be run on enabled APs of the system.
  @param[in] SingleThread          - Indicates whether to execute the function simultaneously or one by one..
  @param[in] WaitEvent             - The event created by the caller.
                                     If it is NULL, then execute in blocking mode.
                                     If it is not NULL, then execute in non-blocking mode.
  @param[in] TimeoutInMicrosecsond - The time limit in microseconds for this AP to finish the function.
                                     Zero means infinity.
  @param[in] ProcArgument          - Pointer to the optional parameter of the assigned function.
  @param[in] FailedCpuList         - The list of processor numbers that fail to finish the function before
                                     TimeoutInMicrosecsond expires.

  @retval EFI_SUCCESS           - In blocking mode, all APs have finished before the timeout expired.
  @retval EFI_SUCCESS           - In non-blocking mode, function has been dispatched to all enabled APs.
  @retval EFI_DEVICE_ERROR      - Caller processor is AP.
  @retval EFI_NOT_STARTED       - No enabled AP exists in the system.
  @retval EFI_NOT_READY         - Any enabled AP is busy.
  @retval EFI_TIMEOUT           - In blocking mode, The timeout expired before all enabled APs have finished.
  @retval EFI_INVALID_PARAMETER - Procedure is NULL.
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_STARTUP_ALL_APS)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  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 lets the caller get one enabled AP to execute a caller-provided
  function. The caller can request the BSP to either wait for the completion
  of the AP or just proceed with the next task by using the EFI event mechanism.
  See EFI_PI_MP_SERVICES_PROTOCOL.StartupAllAPs() for more details on non-blocking
  execution support.  This service may only be called from the BSP.

  This function is used to dispatch one enabled AP to the function specified by
  Procedure passing in the argument specified by ProcedureArgument.  If WaitEvent
  is NULL, execution is in blocking mode. The BSP waits until the AP finishes or
  TimeoutInMicroSecondss expires. Otherwise, execution is in non-blocking mode.
  BSP proceeds to the next task without waiting for the AP. If a non-blocking mode
  is requested after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT is signaled,
  then EFI_UNSUPPORTED must be returned.

  If the timeout specified by TimeoutInMicroseconds expires before the AP returns
  from Procedure, then execution of Procedure by the AP is terminated. The AP is
  available for subsequent calls to EFI_PI_MP_SERVICES_PROTOCOL.StartupAllAPs() and
  EFI_PI_MP_SERVICES_PROTOCOL.StartupThisAP().

  @param[in] This                  - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] Procedure             - A pointer to the function to be run on the designated AP.
  @param[in] ProcessorNumber       - The handle number of AP..
  @param[in] WaitEvent             - The event created by the caller.
                                     If it is NULL, then execute in blocking mode.
                                     If it is not NULL, then execute in non-blocking mode.
  @param[in] TimeoutInMicroseconds - The time limit in microseconds for this AP to finish the function.
                                     Zero means infinity.
  @param[in] ProcArgument          - Pointer to the optional parameter of the assigned function.
  @param[in] Finished              - Indicates whether AP has finished assigned function.
                                     In blocking mode, it is ignored.

  @retval EFI_SUCCESS           - In blocking mode, specified AP has finished before the timeout expires.
  @retval EFI_SUCCESS           - In non-blocking mode, function has been dispatched to specified AP.
  @retval EFI_DEVICE_ERROR      - Caller processor is AP.
  @retval EFI_TIMEOUT           - In blocking mode, the timeout expires before specified AP has finished.
  @retval EFI_NOT_READY         - Specified AP is busy.
  @retval EFI_NOT_FOUND         - Processor with the handle specified by ProcessorNumber does not exist.
  @retval EFI_INVALID_PARAMETER - ProcessorNumber specifies the BSP or disabled AP.
  @retval EFI_INVALID_PARAMETER - Procedure is NULL.
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_STARTUP_THIS_AP)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  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 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.

  This service switches the requested AP to be the BSP from that point onward.
  This service changes the BSP for all purposes. The new BSP can take over the
  execution of the old BSP and continue seamlessly from where the old one left
  off. This service may not be supported after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
  is signaled.

  If the BSP cannot be switched prior to the return from this service, then
  EFI_UNSUPPORTED must be returned.

  @param[in] This                 - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] ProcessorNumber      - The handle number of processor.
  @param[in] EnableOldBSP         - Whether to enable or disable the original BSP.

  @retval EFI_SUCCESS           - BSP successfully switched.
  @retval EFI_DEVICE_ERROR      - Caller processor is AP.
  @retval EFI_NOT_FOUND         - Processor with the handle specified by ProcessorNumber does not exist.
  @retval EFI_INVALID_PARAMETER - ProcessorNumber specifies the BSP or disabled AP.
  @retval EFI_NOT_READY         - Specified AP is busy.
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_SWITCH_BSP)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  IN UINTN                       ProcessorNumber,
  IN BOOLEAN                     EnableOldBSP
  );

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

  This service allows the caller enable or disable an AP from this point onward.
  The caller can optionally specify the health status of the AP by Health. If
  an AP is being disabled, then the state of the disabled AP is implementation
  dependent. If an AP is enabled, then the implementation must guarantee that a
  complete initialization sequence is performed on the AP, so the AP is in a state
  that is compatible with an MP operating system. This service may not be supported
  after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT is signaled.

  If the enable or disable AP operation cannot be completed prior to the return
  from this service, then EFI_UNSUPPORTED must be returned.

  @param[in] This                  - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] ProcessorNumber       - The handle number of processor.
  @param[in] EnableAP              - Indicates whether the newstate of the AP is enabled or disabled.
  @param[in] HealthFlag            - Indicates new health state of the AP..

  @retval EFI_SUCCESS            - AP successfully enabled or disabled.
  @retval EFI_DEVICE_ERROR       - Caller processor is AP.
  @retval EFI_NOT_FOUND          - Processor with the handle specified by ProcessorNumber does not exist.
  @retval EFI_INVALID_PARAMETERS - ProcessorNumber specifies the BSP.
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_ENABLEDISABLEAP)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  IN UINTN                       ProcessorNumber,
  IN BOOLEAN                     EnableAP,
  IN UINT32 *HealthFlag          OPTIONAL
  );

/**
  This return the handle number for the calling processor.  This service may be
  called from the BSP and APs.

  This service returns the processor handle number for the calling processor.
  The returned value is in the range from 0 to the total number of logical
  processors minus 1. The total number of logical processors can be retrieved
  with EFI_PI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors(). This service may be
  called from the BSP and APs. If ProcessorNumber is NULL, then EFI_INVALID_PARAMETER
  is returned. Otherwise, the current processors handle number is returned in
  ProcessorNumber, and EFI_SUCCESS is returned.

  @param[in] This                 - A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
  @param[in] ProcessorNumber      - Pointer to the handle number of AP.

  @retval EFI_SUCCESS           - Processor number successfully returned.
  @retval EFI_INVALID_PARAMETER - ProcessorNumber is NULL
**/
typedef
EFI_STATUS
(EFIAPI *EFI_PI_MP_SERVICES_WHOAMI)(
  IN EFI_PI_MP_SERVICES_PROTOCOL *This,
  OUT UINTN                      *ProcessorNumber
  );

///
/// When installed, the MP Services Protocol produces a collection of services
/// that are needed for MP management.
///
/// Before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, the module
/// that produces this protocol is required to place all APs into an idle state
/// whenever the APs are disabled or the APs are not executing code as requested
/// through the StartupAllAPs() or StartupThisAP() services. The idle state of
/// an AP before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled is
/// implementation dependent.
///
/// After the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, all the APs
/// must be placed in the OS compatible CPU state as defined by the UEFI
/// Specification. Implementations of this protocol may use the UEFI event
/// EFI_EVENT_GROUP_READY_TO_BOOT to force APs into the OS compatible state as
/// defined by the UEFI Specification. Modules that use this protocol must
/// guarantee that all non-blocking mode requests on all APs have been completed
/// before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled. Since the
/// order that event notification functions in the same event group are executed
/// is not deterministic, an event of type EFI_EVENT_GROUP_READY_TO_BOOT cannot
/// be used to guarantee that APs have completed their non-blocking mode requests.
///
/// When the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, the StartAllAPs()
/// and StartupThisAp() services must no longer support non-blocking mode requests.
/// The support for SwitchBSP() and EnableDisableAP() may no longer be supported
/// after this event is signaled. Since UEFI Applications and UEFI OS Loaders
/// execute after the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, these
/// UEFI images must be aware that the functionality of this protocol may be reduced.
///
struct _EFI_PI_MP_SERVICES_PROTOCOL {
  ///
  /// This service retrieves the number of logical processor in the platform and the number of those logical
  /// processors that are enabled on this boot. This service may only be called from the BSP.
  ///
  EFI_PI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS GetNumberOfProcessors;
  ///
  /// This service retrieves detailed MP-related information about any processor on the platform.
  ///
  EFI_PI_MP_SERVICES_GET_PROCESSOR_INFO       GetProcessorInfo;
  ///
  /// This service executes a caller provided function on all enabled APs.
  ///
  EFI_PI_MP_SERVICES_STARTUP_ALL_APS          StartupAllAPs;
  ///
  /// This service lets the caller get one enabled AP to execute a caller-provided function.
  ///
  EFI_PI_MP_SERVICES_STARTUP_THIS_AP          StartupThisAP;
  ///
  /// This service switches the requested AP to be the BSP from that point onward.
  ///
  EFI_PI_MP_SERVICES_SWITCH_BSP               SwitchBSP;
  ///
  /// This service lets the caller enable or disable an AP from this point onward. This service may only be
  /// called from the BSP.
  ///
  EFI_PI_MP_SERVICES_ENABLEDISABLEAP          EnableDisableAP;
  ///
  /// This return the handle number for the calling processor.  This service may be called from the BSP and APs.
  ///
  EFI_PI_MP_SERVICES_WHOAMI                   WhoAmI;
};

extern EFI_GUID gEfiPiMpServiceProtocolGuid;

#endif