MdePkg/Include/Protocol/MpService.h

   1 /** @file
   2   When installed, the MP Services Protocol produces a collection of services
   3   that are needed for MP management.
   4
   5   The MP Services Protocol provides a generalized way of performing following tasks:
   6     - Retrieving information of multi-processor environment and MP-related status of
   7       specific processors.
   8     - Dispatching user-provided function to APs.
   9     - Maintain MP-related processor status.
  10
  11   The MP Services Protocol must be produced on any system with more than one logical
  12   processor.
  13
  14   The Protocol is available only during boot time.
  15
  16   MP Services Protocol is hardware-independent. Most of the logic of this protocol
  17   is architecturally neutral. It abstracts the multi-processor environment and
  18   status of processors, and provides interfaces to retrieve information, maintain,
  19   and dispatch.
  20
  21   MP Services Protocol may be consumed by ACPI module. The ACPI module may use this
  22   protocol to retrieve data that are needed for an MP platform and report them to OS.
  23   MP Services Protocol may also be used to program and configure processors, such
  24   as MTRR synchronization for memory space attributes setting in DXE Services.
  25   MP Services Protocol may be used by non-CPU DXE drivers to speed up platform boot
  26   by taking advantage of the processing capabilities of the APs, for example, using
  27   APs to help test system memory in parallel with other device initialization.
  28   Diagnostics applications may also use this protocol for multi-processor.
  29
  30 Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
  31 SPDX-License-Identifier: BSD-2-Clause-Patent
  32
  33   @par Revision Reference:
  34   This Protocol is defined in the UEFI Platform Initialization Specification 1.2,
  35   Volume 2:Driver Execution Environment Core Interface.
  36
  37 **/
  38
  39 #ifndef _MP_SERVICE_PROTOCOL_H_
  40 #define _MP_SERVICE_PROTOCOL_H_
  41
  42 ///
  43 /// Global ID for the EFI_MP_SERVICES_PROTOCOL.
  44 ///
  45 #define EFI_MP_SERVICES_PROTOCOL_GUID \
  46   { \
  47     0x3fdda605, 0xa76e, 0x4f46, {0xad, 0x29, 0x12, 0xf4, 0x53, 0x1b, 0x3d, 0x08} \
  48   }
  49
  50 ///
  51 /// Forward declaration for the EFI_MP_SERVICES_PROTOCOL.
  52 ///
  53 typedef struct _EFI_MP_SERVICES_PROTOCOL EFI_MP_SERVICES_PROTOCOL;
  54
  55 ///
  56 /// Terminator for a list of failed CPUs returned by StartAllAPs().
  57 ///
  58 #define END_OF_CPU_LIST    0xffffffff
  59
  60 ///
  61 /// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
  62 /// indicates whether the processor is playing the role of BSP. If the bit is 1,
  63 /// then the processor is BSP. Otherwise, it is AP.
  64 ///
  65 #define PROCESSOR_AS_BSP_BIT         0x00000001
  66
  67 ///
  68 /// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
  69 /// indicates whether the processor is enabled. If the bit is 1, then the
  70 /// processor is enabled. Otherwise, it is disabled.
  71 ///
  72 #define PROCESSOR_ENABLED_BIT        0x00000002
  73
  74 ///
  75 /// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
  76 /// indicates whether the processor is healthy. If the bit is 1, then the
  77 /// processor is healthy. Otherwise, some fault has been detected for the processor.
  78 ///
  79 #define PROCESSOR_HEALTH_STATUS_BIT  0x00000004
  80
  81 ///
  82 /// Structure that describes the pyhiscal location of a logical CPU.
  83 ///
  84 typedef struct {
  85   ///
  86   /// Zero-based physical package number that identifies the cartridge of the processor.
  87   ///
  88   UINT32  Package;
  89   ///
  90   /// Zero-based physical core number within package of the processor.
  91   ///
  92   UINT32  Core;
  93   ///
  94   /// Zero-based logical thread number within core of the processor.
  95   ///
  96   UINT32  Thread;
  97 } EFI_CPU_PHYSICAL_LOCATION;
  98
  99 ///
 100 /// Structure that describes information about a logical CPU.
 101 ///
 102 typedef struct {
 103   ///
 104   /// The unique processor ID determined by system hardware.  For IA32 and X64,
 105   /// the processor ID is the same as the Local APIC ID. Only the lower 8 bits
 106   /// are used, and higher bits are reserved.  For IPF, the lower 16 bits contains
 107   /// id/eid, and higher bits are reserved.
 108   ///
 109   UINT64                     ProcessorId;
 110   ///
 111   /// Flags indicating if the processor is BSP or AP, if the processor is enabled
 112   /// or disabled, and if the processor is healthy. Bits 3..31 are reserved and
 113   /// must be 0.
 114   ///
 115   /// <pre>
 116   /// BSP  ENABLED  HEALTH  Description
 117   /// ===  =======  ======  ===================================================
 118   ///  0      0       0     Unhealthy Disabled AP.
 119   ///  0      0       1     Healthy Disabled AP.
 120   ///  0      1       0     Unhealthy Enabled AP.
 121   ///  0      1       1     Healthy Enabled AP.
 122   ///  1      0       0     Invalid. The BSP can never be in the disabled state.
 123   ///  1      0       1     Invalid. The BSP can never be in the disabled state.
 124   ///  1      1       0     Unhealthy Enabled BSP.
 125   ///  1      1       1     Healthy Enabled BSP.
 126   /// </pre>
 127   ///
 128   UINT32                     StatusFlag;
 129   ///
 130   /// The physical location of the processor, including the physical package number
 131   /// that identifies the cartridge, the physical core number within package, and
 132   /// logical thread number within core.
 133   ///
 134   EFI_CPU_PHYSICAL_LOCATION  Location;
 135 } EFI_PROCESSOR_INFORMATION;
 136
 137 /**
 138   This service retrieves the number of logical processor in the platform
 139   and the number of those logical processors that are enabled on this boot.
 140   This service may only be called from the BSP.
 141
 142   This function is used to retrieve the following information:
 143     - The number of logical processors that are present in the system.
 144     - The number of enabled logical processors in the system at the instant
 145       this call is made.
 146
 147   Because MP Service Protocol provides services to enable and disable processors
 148   dynamically, the number of enabled logical processors may vary during the
 149   course of a boot session.
 150
 151   If this service is called from an AP, then EFI_DEVICE_ERROR is returned.
 152   If NumberOfProcessors or NumberOfEnabledProcessors is NULL, then
 153   EFI_INVALID_PARAMETER is returned. Otherwise, the total number of processors
 154   is returned in NumberOfProcessors, the number of currently enabled processor
 155   is returned in NumberOfEnabledProcessors, and EFI_SUCCESS is returned.
 156
 157   @param[in]  This                        A pointer to the EFI_MP_SERVICES_PROTOCOL
 158                                           instance.
 159   @param[out] NumberOfProcessors          Pointer to the total number of logical
 160                                           processors in the system, including the BSP
 161                                           and disabled APs.
 162   @param[out] NumberOfEnabledProcessors   Pointer to the number of enabled logical
 163                                           processors that exist in system, including
 164                                           the BSP.
 165
 166   @retval EFI_SUCCESS             The number of logical processors and enabled
 167                                   logical processors was retrieved.
 168   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 169   @retval EFI_INVALID_PARAMETER   NumberOfProcessors is NULL.
 170   @retval EFI_INVALID_PARAMETER   NumberOfEnabledProcessors is NULL.
 171
 172 **/
 173 typedef
 174 EFI_STATUS
 175 (EFIAPI *EFI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS)(
 176   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 177   OUT UINTN                     *NumberOfProcessors,
 178   OUT UINTN                     *NumberOfEnabledProcessors
 179   );
 180
 181 /**
 182   Gets detailed MP-related information on the requested processor at the
 183   instant this call is made. This service may only be called from the BSP.
 184
 185   This service retrieves detailed MP-related information about any processor
 186   on the platform. Note the following:
 187     - The processor information may change during the course of a boot session.
 188     - The information presented here is entirely MP related.
 189
 190   Information regarding the number of caches and their sizes, frequency of operation,
 191   slot numbers is all considered platform-related information and is not provided
 192   by this service.
 193
 194   @param[in]  This                  A pointer to the EFI_MP_SERVICES_PROTOCOL
 195                                     instance.
 196   @param[in]  ProcessorNumber       The handle number of processor.
 197   @param[out] ProcessorInfoBuffer   A pointer to the buffer where information for
 198                                     the requested processor is deposited.
 199
 200   @retval EFI_SUCCESS             Processor information was returned.
 201   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 202   @retval EFI_INVALID_PARAMETER   ProcessorInfoBuffer is NULL.
 203   @retval EFI_NOT_FOUND           The processor with the handle specified by
 204                                   ProcessorNumber does not exist in the platform.
 205
 206 **/
 207 typedef
 208 EFI_STATUS
 209 (EFIAPI *EFI_MP_SERVICES_GET_PROCESSOR_INFO)(
 210   IN  EFI_MP_SERVICES_PROTOCOL   *This,
 211   IN  UINTN                      ProcessorNumber,
 212   OUT EFI_PROCESSOR_INFORMATION  *ProcessorInfoBuffer
 213   );
 214
 215 /**
 216   This service executes a caller provided function on all enabled APs. APs can
 217   run either simultaneously or one at a time in sequence. This service supports
 218   both blocking and non-blocking requests. The non-blocking requests use EFI
 219   events so the BSP can detect when the APs have finished. This service may only
 220   be called from the BSP.
 221
 222   This function is used to dispatch all the enabled APs to the function specified
 223   by Procedure.  If any enabled AP is busy, then EFI_NOT_READY is returned
 224   immediately and Procedure is not started on any AP.
 225
 226   If SingleThread is TRUE, all the enabled APs execute the function specified by
 227   Procedure one by one, in ascending order of processor handle number. Otherwise,
 228   all the enabled APs execute the function specified by Procedure simultaneously.
 229
 230   If WaitEvent is NULL, execution is in blocking mode. The BSP waits until all
 231   APs finish or TimeoutInMicroSecs expires. Otherwise, execution is in non-blocking
 232   mode, and the BSP returns from this service without waiting for APs. If a
 233   non-blocking mode is requested after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
 234   is signaled, then EFI_UNSUPPORTED must be returned.
 235
 236   If the timeout specified by TimeoutInMicroseconds expires before all APs return
 237   from Procedure, then Procedure on the failed APs is terminated. All enabled APs
 238   are always available for further calls to EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 239   and EFI_MP_SERVICES_PROTOCOL.StartupThisAP(). If FailedCpuList is not NULL, its
 240   content points to the list of processor handle numbers in which Procedure was
 241   terminated.
 242
 243   Note: It is the responsibility of the consumer of the EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 244   to make sure that the nature of the code that is executed on the BSP and the
 245   dispatched APs is well controlled. The MP Services Protocol does not guarantee
 246   that the Procedure function is MP-safe. Hence, the tasks that can be run in
 247   parallel are limited to certain independent tasks and well-controlled exclusive
 248   code. EFI services and protocols may not be called by APs unless otherwise
 249   specified.
 250
 251   In blocking execution mode, BSP waits until all APs finish or
 252   TimeoutInMicroSeconds expires.
 253
 254   In non-blocking execution mode, BSP is freed to return to the caller and then
 255   proceed to the next task without having to wait for APs. The following
 256   sequence needs to occur in a non-blocking execution mode:
 257
 258     -# The caller that intends to use this MP Services Protocol in non-blocking
 259        mode creates WaitEvent by calling the EFI CreateEvent() service.  The caller
 260        invokes EFI_MP_SERVICES_PROTOCOL.StartupAllAPs(). If the parameter WaitEvent
 261        is not NULL, then StartupAllAPs() executes in non-blocking mode. It requests
 262        the function specified by Procedure to be started on all the enabled APs,
 263        and releases the BSP to continue with other tasks.
 264     -# The caller can use the CheckEvent() and WaitForEvent() services to check
 265        the state of the WaitEvent created in step 1.
 266     -# When the APs complete their task or TimeoutInMicroSecondss expires, the MP
 267        Service signals WaitEvent by calling the EFI SignalEvent() function. If
 268        FailedCpuList is not NULL, its content is available when WaitEvent is
 269        signaled. If all APs returned from Procedure prior to the timeout, then
 270        FailedCpuList is set to NULL. If not all APs return from Procedure before
 271        the timeout, then FailedCpuList is filled in with the list of the failed
 272        APs. The buffer is allocated by MP Service Protocol using AllocatePool().
 273        It is the caller's responsibility to free the buffer with FreePool() service.
 274     -# This invocation of SignalEvent() function informs the caller that invoked
 275        EFI_MP_SERVICES_PROTOCOL.StartupAllAPs() that either all the APs completed
 276        the specified task or a timeout occurred. The contents of FailedCpuList
 277        can be examined to determine which APs did not complete the specified task
 278        prior to the timeout.
 279
 280   @param[in]  This                    A pointer to the EFI_MP_SERVICES_PROTOCOL
 281                                       instance.
 282   @param[in]  Procedure               A pointer to the function to be run on
 283                                       enabled APs of the system. See type
 284                                       EFI_AP_PROCEDURE.
 285   @param[in]  SingleThread            If TRUE, then all the enabled APs execute
 286                                       the function specified by Procedure one by
 287                                       one, in ascending order of processor handle
 288                                       number.  If FALSE, then all the enabled APs
 289                                       execute the function specified by Procedure
 290                                       simultaneously.
 291   @param[in]  WaitEvent               The event created by the caller with CreateEvent()
 292                                       service.  If it is NULL, then execute in
 293                                       blocking mode. BSP waits until all APs finish
 294                                       or TimeoutInMicroSeconds expires.  If it's
 295                                       not NULL, then execute in non-blocking mode.
 296                                       BSP requests the function specified by
 297                                       Procedure to be started on all the enabled
 298                                       APs, and go on executing immediately. If
 299                                       all return from Procedure, or TimeoutInMicroSeconds
 300                                       expires, this event is signaled. The BSP
 301                                       can use the CheckEvent() or WaitForEvent()
 302                                       services to check the state of event.  Type
 303                                       EFI_EVENT is defined in CreateEvent() in
 304                                       the Unified Extensible Firmware Interface
 305                                       Specification.
 306   @param[in]  TimeoutInMicrosecsond   Indicates the time limit in microseconds for
 307                                       APs to return from Procedure, either for
 308                                       blocking or non-blocking mode. Zero means
 309                                       infinity.  If the timeout expires before
 310                                       all APs return from Procedure, then Procedure
 311                                       on the failed APs is terminated. All enabled
 312                                       APs are available for next function assigned
 313                                       by EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 314                                       or EFI_MP_SERVICES_PROTOCOL.StartupThisAP().
 315                                       If the timeout expires in blocking mode,
 316                                       BSP returns EFI_TIMEOUT.  If the timeout
 317                                       expires in non-blocking mode, WaitEvent
 318                                       is signaled with SignalEvent().
 319   @param[in]  ProcedureArgument       The parameter passed into Procedure for
 320                                       all APs.
 321   @param[out] FailedCpuList           If NULL, this parameter is ignored. Otherwise,
 322                                       if all APs finish successfully, then its
 323                                       content is set to NULL. If not all APs
 324                                       finish before timeout expires, then its
 325                                       content is set to address of the buffer
 326                                       holding handle numbers of the failed APs.
 327                                       The buffer is allocated by MP Service Protocol,
 328                                       and it's the caller's responsibility to
 329                                       free the buffer with FreePool() service.
 330                                       In blocking mode, it is ready for consumption
 331                                       when the call returns. In non-blocking mode,
 332                                       it is ready when WaitEvent is signaled.  The
 333                                       list of failed CPU is terminated by
 334                                       END_OF_CPU_LIST.
 335
 336   @retval EFI_SUCCESS             In blocking mode, all APs have finished before
 337                                   the timeout expired.
 338   @retval EFI_SUCCESS             In non-blocking mode, function has been dispatched
 339                                   to all enabled APs.
 340   @retval EFI_UNSUPPORTED         A non-blocking mode request was made after the
 341                                   UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was
 342                                   signaled.
 343   @retval EFI_DEVICE_ERROR        Caller processor is AP.
 344   @retval EFI_NOT_STARTED         No enabled APs exist in the system.
 345   @retval EFI_NOT_READY           Any enabled APs are busy.
 346   @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
 347                                   all enabled APs have finished.
 348   @retval EFI_INVALID_PARAMETER   Procedure is NULL.
 349
 350 **/
 351 typedef
 352 EFI_STATUS
 353 (EFIAPI *EFI_MP_SERVICES_STARTUP_ALL_APS)(
 354   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 355   IN  EFI_AP_PROCEDURE          Procedure,
 356   IN  BOOLEAN                   SingleThread,
 357   IN  EFI_EVENT                 WaitEvent               OPTIONAL,
 358   IN  UINTN                     TimeoutInMicroSeconds,
 359   IN  VOID                      *ProcedureArgument      OPTIONAL,
 360   OUT UINTN                     **FailedCpuList         OPTIONAL
 361   );
 362
 363 /**
 364   This service lets the caller get one enabled AP to execute a caller-provided
 365   function. The caller can request the BSP to either wait for the completion
 366   of the AP or just proceed with the next task by using the EFI event mechanism.
 367   See EFI_MP_SERVICES_PROTOCOL.StartupAllAPs() for more details on non-blocking
 368   execution support.  This service may only be called from the BSP.
 369
 370   This function is used to dispatch one enabled AP to the function specified by
 371   Procedure passing in the argument specified by ProcedureArgument.  If WaitEvent
 372   is NULL, execution is in blocking mode. The BSP waits until the AP finishes or
 373   TimeoutInMicroSecondss expires. Otherwise, execution is in non-blocking mode.
 374   BSP proceeds to the next task without waiting for the AP. If a non-blocking mode
 375   is requested after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT is signaled,
 376   then EFI_UNSUPPORTED must be returned.
 377
 378   If the timeout specified by TimeoutInMicroseconds expires before the AP returns
 379   from Procedure, then execution of Procedure by the AP is terminated. The AP is
 380   available for subsequent calls to EFI_MP_SERVICES_PROTOCOL.StartupAllAPs() and
 381   EFI_MP_SERVICES_PROTOCOL.StartupThisAP().
 382
 383   @param[in]  This                    A pointer to the EFI_MP_SERVICES_PROTOCOL
 384                                       instance.
 385   @param[in]  Procedure               A pointer to the function to be run on the
 386                                       designated AP of the system. See type
 387                                       EFI_AP_PROCEDURE.
 388   @param[in]  ProcessorNumber         The handle number of the AP. The range is
 389                                       from 0 to the total number of logical
 390                                       processors minus 1. The total number of
 391                                       logical processors can be retrieved by
 392                                       EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 393   @param[in]  WaitEvent               The event created by the caller with CreateEvent()
 394                                       service.  If it is NULL, then execute in
 395                                       blocking mode. BSP waits until this AP finish
 396                                       or TimeoutInMicroSeconds expires.  If it's
 397                                       not NULL, then execute in non-blocking mode.
 398                                       BSP requests the function specified by
 399                                       Procedure to be started on this AP,
 400                                       and go on executing immediately. If this AP
 401                                       return from Procedure or TimeoutInMicroSeconds
 402                                       expires, this event is signaled. The BSP
 403                                       can use the CheckEvent() or WaitForEvent()
 404                                       services to check the state of event.  Type
 405                                       EFI_EVENT is defined in CreateEvent() in
 406                                       the Unified Extensible Firmware Interface
 407                                       Specification.
 408   @param[in]  TimeoutInMicrosecsond   Indicates the time limit in microseconds for
 409                                       this AP to finish this Procedure, either for
 410                                       blocking or non-blocking mode. Zero means
 411                                       infinity.  If the timeout expires before
 412                                       this AP returns from Procedure, then Procedure
 413                                       on the AP is terminated. The
 414                                       AP is available for next function assigned
 415                                       by EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 416                                       or EFI_MP_SERVICES_PROTOCOL.StartupThisAP().
 417                                       If the timeout expires in blocking mode,
 418                                       BSP returns EFI_TIMEOUT.  If the timeout
 419                                       expires in non-blocking mode, WaitEvent
 420                                       is signaled with SignalEvent().
 421   @param[in]  ProcedureArgument       The parameter passed into Procedure on the
 422                                       specified AP.
 423   @param[out] Finished                If NULL, this parameter is ignored.  In
 424                                       blocking mode, this parameter is ignored.
 425                                       In non-blocking mode, if AP returns from
 426                                       Procedure before the timeout expires, its
 427                                       content is set to TRUE. Otherwise, the
 428                                       value is set to FALSE. The caller can
 429                                       determine if the AP returned from Procedure
 430                                       by evaluating this value.
 431
 432   @retval EFI_SUCCESS             In blocking mode, specified AP finished before
 433                                   the timeout expires.
 434   @retval EFI_SUCCESS             In non-blocking mode, the function has been
 435                                   dispatched to specified AP.
 436   @retval EFI_UNSUPPORTED         A non-blocking mode request was made after the
 437                                   UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was
 438                                   signaled.
 439   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 440   @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
 441                                   the specified AP has finished.
 442   @retval EFI_NOT_READY           The specified AP is busy.
 443   @retval EFI_NOT_FOUND           The processor with the handle specified by
 444                                   ProcessorNumber does not exist.
 445   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the BSP or disabled AP.
 446   @retval EFI_INVALID_PARAMETER   Procedure is NULL.
 447
 448 **/
 449 typedef
 450 EFI_STATUS
 451 (EFIAPI *EFI_MP_SERVICES_STARTUP_THIS_AP)(
 452   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 453   IN  EFI_AP_PROCEDURE          Procedure,
 454   IN  UINTN                     ProcessorNumber,
 455   IN  EFI_EVENT                 WaitEvent               OPTIONAL,
 456   IN  UINTN                     TimeoutInMicroseconds,
 457   IN  VOID                      *ProcedureArgument      OPTIONAL,
 458   OUT BOOLEAN                   *Finished               OPTIONAL
 459   );
 460
 461 /**
 462   This service switches the requested AP to be the BSP from that point onward.
 463   This service changes the BSP for all purposes.   This call can only be performed
 464   by the current BSP.
 465
 466   This service switches the requested AP to be the BSP from that point onward.
 467   This service changes the BSP for all purposes. The new BSP can take over the
 468   execution of the old BSP and continue seamlessly from where the old one left
 469   off. This service may not be supported after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
 470   is signaled.
 471
 472   If the BSP cannot be switched prior to the return from this service, then
 473   EFI_UNSUPPORTED must be returned.
 474
 475   @param[in] This              A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
 476   @param[in] ProcessorNumber   The handle number of AP that is to become the new
 477                                BSP. The range is from 0 to the total number of
 478                                logical processors minus 1. The total number of
 479                                logical processors can be retrieved by
 480                                EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 481   @param[in] EnableOldBSP      If TRUE, then the old BSP will be listed as an
 482                                enabled AP. Otherwise, it will be disabled.
 483
 484   @retval EFI_SUCCESS             BSP successfully switched.
 485   @retval EFI_UNSUPPORTED         Switching the BSP cannot be completed prior to
 486                                   this service returning.
 487   @retval EFI_UNSUPPORTED         Switching the BSP is not supported.
 488   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 489   @retval EFI_NOT_FOUND           The processor with the handle specified by
 490                                   ProcessorNumber does not exist.
 491   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the current BSP or
 492                                   a disabled AP.
 493   @retval EFI_NOT_READY           The specified AP is busy.
 494
 495 **/
 496 typedef
 497 EFI_STATUS
 498 (EFIAPI *EFI_MP_SERVICES_SWITCH_BSP)(
 499   IN EFI_MP_SERVICES_PROTOCOL  *This,
 500   IN  UINTN                    ProcessorNumber,
 501   IN  BOOLEAN                  EnableOldBSP
 502   );
 503
 504 /**
 505   This service lets the caller enable or disable an AP from this point onward.
 506   This service may only be called from the BSP.
 507
 508   This service allows the caller enable or disable an AP from this point onward.
 509   The caller can optionally specify the health status of the AP by Health. If
 510   an AP is being disabled, then the state of the disabled AP is implementation
 511   dependent. If an AP is enabled, then the implementation must guarantee that a
 512   complete initialization sequence is performed on the AP, so the AP is in a state
 513   that is compatible with an MP operating system. This service may not be supported
 514   after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT is signaled.
 515
 516   If the enable or disable AP operation cannot be completed prior to the return
 517   from this service, then EFI_UNSUPPORTED must be returned.
 518
 519   @param[in] This              A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
 520   @param[in] ProcessorNumber   The handle number of AP.
 521                                The range is from 0 to the total number of
 522                                logical processors minus 1. The total number of
 523                                logical processors can be retrieved by
 524                                EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 525   @param[in] EnableAP          Specifies the new state for the processor for
 526                                enabled, FALSE for disabled.
 527   @param[in] HealthFlag        If not NULL, a pointer to a value that specifies
 528                                the new health status of the AP. This flag
 529                                corresponds to StatusFlag defined in
 530                                EFI_MP_SERVICES_PROTOCOL.GetProcessorInfo(). Only
 531                                the PROCESSOR_HEALTH_STATUS_BIT is used. All other
 532                                bits are ignored.  If it is NULL, this parameter
 533                                is ignored.
 534
 535   @retval EFI_SUCCESS             The specified AP was enabled or disabled successfully.
 536   @retval EFI_UNSUPPORTED         Enabling or disabling an AP cannot be completed
 537                                   prior to this service returning.
 538   @retval EFI_UNSUPPORTED         Enabling or disabling an AP is not supported.
 539   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 540   @retval EFI_NOT_FOUND           Processor with the handle specified by ProcessorNumber
 541                                   does not exist.
 542   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the BSP.
 543
 544 **/
 545 typedef
 546 EFI_STATUS
 547 (EFIAPI *EFI_MP_SERVICES_ENABLEDISABLEAP)(
 548   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 549   IN  UINTN                     ProcessorNumber,
 550   IN  BOOLEAN                   EnableAP,
 551   IN  UINT32                    *HealthFlag OPTIONAL
 552   );
 553
 554 /**
 555   This return the handle number for the calling processor.  This service may be
 556   called from the BSP and APs.
 557
 558   This service returns the processor handle number for the calling processor.
 559   The returned value is in the range from 0 to the total number of logical
 560   processors minus 1. The total number of logical processors can be retrieved
 561   with EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors(). This service may be
 562   called from the BSP and APs. If ProcessorNumber is NULL, then EFI_INVALID_PARAMETER
 563   is returned. Otherwise, the current processors handle number is returned in
 564   ProcessorNumber, and EFI_SUCCESS is returned.
 565
 566   @param[in] This              A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
 567   @param[in] ProcessorNumber   Pointer to the handle number of AP.
 568                                The range is from 0 to the total number of
 569                                logical processors minus 1. The total number of
 570                                logical processors can be retrieved by
 571                                EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 572
 573   @retval EFI_SUCCESS             The current processor handle number was returned
 574                                   in ProcessorNumber.
 575   @retval EFI_INVALID_PARAMETER   ProcessorNumber is NULL.
 576
 577 **/
 578 typedef
 579 EFI_STATUS
 580 (EFIAPI *EFI_MP_SERVICES_WHOAMI)(
 581   IN EFI_MP_SERVICES_PROTOCOL  *This,
 582   OUT UINTN                    *ProcessorNumber
 583   );
 584
 585 ///
 586 /// When installed, the MP Services Protocol produces a collection of services
 587 /// that are needed for MP management.
 588 ///
 589 /// Before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, the module
 590 /// that produces this protocol is required to place all APs into an idle state
 591 /// whenever the APs are disabled or the APs are not executing code as requested
 592 /// through the StartupAllAPs() or StartupThisAP() services. The idle state of
 593 /// an AP before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled is
 594 /// implementation dependent.
 595 ///
 596 /// After the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, all the APs
 597 /// must be placed in the OS compatible CPU state as defined by the UEFI
 598 /// Specification. Implementations of this protocol may use the UEFI event
 599 /// EFI_EVENT_GROUP_READY_TO_BOOT to force APs into the OS compatible state as
 600 /// defined by the UEFI Specification. Modules that use this protocol must
 601 /// guarantee that all non-blocking mode requests on all APs have been completed
 602 /// before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled. Since the
 603 /// order that event notification functions in the same event group are executed
 604 /// is not deterministic, an event of type EFI_EVENT_GROUP_READY_TO_BOOT cannot
 605 /// be used to guarantee that APs have completed their non-blocking mode requests.
 606 ///
 607 /// When the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, the StartAllAPs()
 608 /// and StartupThisAp() services must no longer support non-blocking mode requests.
 609 /// The support for SwitchBSP() and EnableDisableAP() may no longer be supported
 610 /// after this event is signaled. Since UEFI Applications and UEFI OS Loaders
 611 /// execute after the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, these
 612 /// UEFI images must be aware that the functionality of this protocol may be reduced.
 613 ///
 614 struct _EFI_MP_SERVICES_PROTOCOL {
 615   EFI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS  GetNumberOfProcessors;
 616   EFI_MP_SERVICES_GET_PROCESSOR_INFO        GetProcessorInfo;
 617   EFI_MP_SERVICES_STARTUP_ALL_APS           StartupAllAPs;
 618   EFI_MP_SERVICES_STARTUP_THIS_AP           StartupThisAP;
 619   EFI_MP_SERVICES_SWITCH_BSP                SwitchBSP;
 620   EFI_MP_SERVICES_ENABLEDISABLEAP           EnableDisableAP;
 621   EFI_MP_SERVICES_WHOAMI                    WhoAmI;
 622 };
 623
 624 extern EFI_GUID gEfiMpServiceProtocolGuid;
 625
 626 #endif