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 This program and the accompanying materials are licensed and made available under
  32 the terms and conditions of the BSD License that accompanies this distribution.
  33 The full text of the license may be found at
  34 http://opensource.org/licenses/bsd-license.php.
  35
  36 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  37 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  38
  39   @par Revision Reference:
  40   This Protocol is defined in the UEFI Platform Initialization Specification 1.2,
  41   Volume 2:Driver Execution Environment Core Interface.
  42
  43 **/
  44
  45 #ifndef _MP_SERVICE_PROTOCOL_H_
  46 #define _MP_SERVICE_PROTOCOL_H_
  47
  48 ///
  49 /// Global ID for the EFI_MP_SERVICES_PROTOCOL.
  50 ///
  51 #define EFI_MP_SERVICES_PROTOCOL_GUID \
  52   { \
  53     0x3fdda605, 0xa76e, 0x4f46, {0xad, 0x29, 0x12, 0xf4, 0x53, 0x1b, 0x3d, 0x08} \
  54   }
  55
  56 ///
  57 /// Forward declaration for the EFI_MP_SERVICES_PROTOCOL.
  58 ///
  59 typedef struct _EFI_MP_SERVICES_PROTOCOL EFI_MP_SERVICES_PROTOCOL;
  60
  61 ///
  62 /// Terminator for a list of failed CPUs returned by StartAllAPs().
  63 ///
  64 #define END_OF_CPU_LIST    0xffffffff
  65
  66 ///
  67 /// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
  68 /// indicates whether the processor is playing the role of BSP. If the bit is 1,
  69 /// then the processor is BSP. Otherwise, it is AP.
  70 ///
  71 #define PROCESSOR_AS_BSP_BIT         0x00000001
  72
  73 ///
  74 /// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
  75 /// indicates whether the processor is enabled. If the bit is 1, then the
  76 /// processor is enabled. Otherwise, it is disabled.
  77 ///
  78 #define PROCESSOR_ENABLED_BIT        0x00000002
  79
  80 ///
  81 /// This bit is used in the StatusFlag field of EFI_PROCESSOR_INFORMATION and
  82 /// indicates whether the processor is healthy. If the bit is 1, then the
  83 /// processor is healthy. Otherwise, some fault has been detected for the processor.
  84 ///
  85 #define PROCESSOR_HEALTH_STATUS_BIT  0x00000004
  86
  87 ///
  88 /// Structure that describes the pyhiscal location of a logical CPU.
  89 ///
  90 typedef struct {
  91   ///
  92   /// Zero-based physical package number that identifies the cartridge of the processor.
  93   ///
  94   UINT32  Package;
  95   ///
  96   /// Zero-based physical core number within package of the processor.
  97   ///
  98   UINT32  Core;
  99   ///
 100   /// Zero-based logical thread number within core of the processor.
 101   ///
 102   UINT32  Thread;
 103 } EFI_CPU_PHYSICAL_LOCATION;
 104
 105 ///
 106 /// Structure that describes information about a logical CPU.
 107 ///
 108 typedef struct {
 109   ///
 110   /// The unique processor ID determined by system hardware.  For IA32 and X64,
 111   /// the processor ID is the same as the Local APIC ID. Only the lower 8 bits
 112   /// are used, and higher bits are reserved.  For IPF, the lower 16 bits contains
 113   /// id/eid, and higher bits are reserved.
 114   ///
 115   UINT64                     ProcessorId;
 116   ///
 117   /// Flags indicating if the processor is BSP or AP, if the processor is enabled
 118   /// or disabled, and if the processor is healthy. Bits 3..31 are reserved and
 119   /// must be 0.
 120   ///
 121   /// <pre>
 122   /// BSP  ENABLED  HEALTH  Description
 123   /// ===  =======  ======  ===================================================
 124   ///  0      0       0     Unhealthy Disabled AP.
 125   ///  0      0       1     Healthy Disabled AP.
 126   ///  0      1       0     Unhealthy Enabled AP.
 127   ///  0      1       1     Healthy Enabled AP.
 128   ///  1      0       0     Invalid. The BSP can never be in the disabled state.
 129   ///  1      0       1     Invalid. The BSP can never be in the disabled state.
 130   ///  1      1       0     Unhealthy Enabled BSP.
 131   ///  1      1       1     Healthy Enabled BSP.
 132   /// </pre>
 133   ///
 134   UINT32                     StatusFlag;
 135   ///
 136   /// The physical location of the processor, including the physical package number
 137   /// that identifies the cartridge, the physical core number within package, and
 138   /// logical thread number within core.
 139   ///
 140   EFI_CPU_PHYSICAL_LOCATION  Location;
 141 } EFI_PROCESSOR_INFORMATION;
 142
 143 /**
 144   This service retrieves the number of logical processor in the platform
 145   and the number of those logical processors that are enabled on this boot.
 146   This service may only be called from the BSP.
 147
 148   This function is used to retrieve the following information:
 149     - The number of logical processors that are present in the system.
 150     - The number of enabled logical processors in the system at the instant
 151       this call is made.
 152
 153   Because MP Service Protocol provides services to enable and disable processors
 154   dynamically, the number of enabled logical processors may vary during the
 155   course of a boot session.
 156
 157   If this service is called from an AP, then EFI_DEVICE_ERROR is returned.
 158   If NumberOfProcessors or NumberOfEnabledProcessors is NULL, then
 159   EFI_INVALID_PARAMETER is returned. Otherwise, the total number of processors
 160   is returned in NumberOfProcessors, the number of currently enabled processor
 161   is returned in NumberOfEnabledProcessors, and EFI_SUCCESS is returned.
 162
 163   @param[in]  This                        A pointer to the EFI_MP_SERVICES_PROTOCOL
 164                                           instance.
 165   @param[out] NumberOfProcessors          Pointer to the total number of logical
 166                                           processors in the system, including the BSP
 167                                           and disabled APs.
 168   @param[out] NumberOfEnabledProcessors   Pointer to the number of enabled logical
 169                                           processors that exist in system, including
 170                                           the BSP.
 171
 172   @retval EFI_SUCCESS             The number of logical processors and enabled
 173                                   logical processors was retrieved.
 174   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 175   @retval EFI_INVALID_PARAMETER   NumberOfProcessors is NULL.
 176   @retval EFI_INVALID_PARAMETER   NumberOfEnabledProcessors is NULL.
 177
 178 **/
 179 typedef
 180 EFI_STATUS
 181 (EFIAPI *EFI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS)(
 182   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 183   OUT UINTN                     *NumberOfProcessors,
 184   OUT UINTN                     *NumberOfEnabledProcessors
 185   );
 186
 187 /**
 188   Gets detailed MP-related information on the requested processor at the
 189   instant this call is made. This service may only be called from the BSP.
 190
 191   This service retrieves detailed MP-related information about any processor
 192   on the platform. Note the following:
 193     - The processor information may change during the course of a boot session.
 194     - The information presented here is entirely MP related.
 195
 196   Information regarding the number of caches and their sizes, frequency of operation,
 197   slot numbers is all considered platform-related information and is not provided
 198   by this service.
 199
 200   @param[in]  This                  A pointer to the EFI_MP_SERVICES_PROTOCOL
 201                                     instance.
 202   @param[in]  ProcessorNumber       The handle number of processor.
 203   @param[out] ProcessorInfoBuffer   A pointer to the buffer where information for
 204                                     the requested processor is deposited.
 205
 206   @retval EFI_SUCCESS             Processor information was returned.
 207   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 208   @retval EFI_INVALID_PARAMETER   ProcessorInfoBuffer is NULL.
 209   @retval EFI_NOT_FOUND           The processor with the handle specified by
 210                                   ProcessorNumber does not exist in the platform.
 211
 212 **/
 213 typedef
 214 EFI_STATUS
 215 (EFIAPI *EFI_MP_SERVICES_GET_PROCESSOR_INFO)(
 216   IN  EFI_MP_SERVICES_PROTOCOL   *This,
 217   IN  UINTN                      ProcessorNumber,
 218   OUT EFI_PROCESSOR_INFORMATION  *ProcessorInfoBuffer
 219   );
 220
 221 /**
 222   This service executes a caller provided function on all enabled APs. APs can
 223   run either simultaneously or one at a time in sequence. This service supports
 224   both blocking and non-blocking requests. The non-blocking requests use EFI
 225   events so the BSP can detect when the APs have finished. This service may only
 226   be called from the BSP.
 227
 228   This function is used to dispatch all the enabled APs to the function specified
 229   by Procedure.  If any enabled AP is busy, then EFI_NOT_READY is returned
 230   immediately and Procedure is not started on any AP.
 231
 232   If SingleThread is TRUE, all the enabled APs execute the function specified by
 233   Procedure one by one, in ascending order of processor handle number. Otherwise,
 234   all the enabled APs execute the function specified by Procedure simultaneously.
 235
 236   If WaitEvent is NULL, execution is in blocking mode. The BSP waits until all
 237   APs finish or TimeoutInMicroSecs expires. Otherwise, execution is in non-blocking
 238   mode, and the BSP returns from this service without waiting for APs. If a
 239   non-blocking mode is requested after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
 240   is signaled, then EFI_UNSUPPORTED must be returned.
 241
 242   If the timeout specified by TimeoutInMicroseconds expires before all APs return
 243   from Procedure, then Procedure on the failed APs is terminated. All enabled APs
 244   are always available for further calls to EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 245   and EFI_MP_SERVICES_PROTOCOL.StartupThisAP(). If FailedCpuList is not NULL, its
 246   content points to the list of processor handle numbers in which Procedure was
 247   terminated.
 248
 249   Note: It is the responsibility of the consumer of the EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 250   to make sure that the nature of the code that is executed on the BSP and the
 251   dispatched APs is well controlled. The MP Services Protocol does not guarantee
 252   that the Procedure function is MP-safe. Hence, the tasks that can be run in
 253   parallel are limited to certain independent tasks and well-controlled exclusive
 254   code. EFI services and protocols may not be called by APs unless otherwise
 255   specified.
 256
 257   In blocking execution mode, BSP waits until all APs finish or
 258   TimeoutInMicroSeconds expires.
 259
 260   In non-blocking execution mode, BSP is freed to return to the caller and then
 261   proceed to the next task without having to wait for APs. The following
 262   sequence needs to occur in a non-blocking execution mode:
 263
 264     -# The caller that intends to use this MP Services Protocol in non-blocking
 265        mode creates WaitEvent by calling the EFI CreateEvent() service.  The caller
 266        invokes EFI_MP_SERVICES_PROTOCOL.StartupAllAPs(). If the parameter WaitEvent
 267        is not NULL, then StartupAllAPs() executes in non-blocking mode. It requests
 268        the function specified by Procedure to be started on all the enabled APs,
 269        and releases the BSP to continue with other tasks.
 270     -# The caller can use the CheckEvent() and WaitForEvent() services to check
 271        the state of the WaitEvent created in step 1.
 272     -# When the APs complete their task or TimeoutInMicroSecondss expires, the MP
 273        Service signals WaitEvent by calling the EFI SignalEvent() function. If
 274        FailedCpuList is not NULL, its content is available when WaitEvent is
 275        signaled. If all APs returned from Procedure prior to the timeout, then
 276        FailedCpuList is set to NULL. If not all APs return from Procedure before
 277        the timeout, then FailedCpuList is filled in with the list of the failed
 278        APs. The buffer is allocated by MP Service Protocol using AllocatePool().
 279        It is the caller's responsibility to free the buffer with FreePool() service.
 280     -# This invocation of SignalEvent() function informs the caller that invoked
 281        EFI_MP_SERVICES_PROTOCOL.StartupAllAPs() that either all the APs completed
 282        the specified task or a timeout occurred. The contents of FailedCpuList
 283        can be examined to determine which APs did not complete the specified task
 284        prior to the timeout.
 285
 286   @param[in]  This                    A pointer to the EFI_MP_SERVICES_PROTOCOL
 287                                       instance.
 288   @param[in]  Procedure               A pointer to the function to be run on
 289                                       enabled APs of the system. See type
 290                                       EFI_AP_PROCEDURE.
 291   @param[in]  SingleThread            If TRUE, then all the enabled APs execute
 292                                       the function specified by Procedure one by
 293                                       one, in ascending order of processor handle
 294                                       number.  If FALSE, then all the enabled APs
 295                                       execute the function specified by Procedure
 296                                       simultaneously.
 297   @param[in]  WaitEvent               The event created by the caller with CreateEvent()
 298                                       service.  If it is NULL, then execute in
 299                                       blocking mode. BSP waits until all APs finish
 300                                       or TimeoutInMicroSeconds expires.  If it's
 301                                       not NULL, then execute in non-blocking mode.
 302                                       BSP requests the function specified by
 303                                       Procedure to be started on all the enabled
 304                                       APs, and go on executing immediately. If
 305                                       all return from Procedure, or TimeoutInMicroSeconds
 306                                       expires, this event is signaled. The BSP
 307                                       can use the CheckEvent() or WaitForEvent()
 308                                       services to check the state of event.  Type
 309                                       EFI_EVENT is defined in CreateEvent() in
 310                                       the Unified Extensible Firmware Interface
 311                                       Specification.
 312   @param[in]  TimeoutInMicrosecsond   Indicates the time limit in microseconds for
 313                                       APs to return from Procedure, either for
 314                                       blocking or non-blocking mode. Zero means
 315                                       infinity.  If the timeout expires before
 316                                       all APs return from Procedure, then Procedure
 317                                       on the failed APs is terminated. All enabled
 318                                       APs are available for next function assigned
 319                                       by EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 320                                       or EFI_MP_SERVICES_PROTOCOL.StartupThisAP().
 321                                       If the timeout expires in blocking mode,
 322                                       BSP returns EFI_TIMEOUT.  If the timeout
 323                                       expires in non-blocking mode, WaitEvent
 324                                       is signaled with SignalEvent().
 325   @param[in]  ProcedureArgument       The parameter passed into Procedure for
 326                                       all APs.
 327   @param[out] FailedCpuList           If NULL, this parameter is ignored. Otherwise,
 328                                       if all APs finish successfully, then its
 329                                       content is set to NULL. If not all APs
 330                                       finish before timeout expires, then its
 331                                       content is set to address of the buffer
 332                                       holding handle numbers of the failed APs.
 333                                       The buffer is allocated by MP Service Protocol,
 334                                       and it's the caller's responsibility to
 335                                       free the buffer with FreePool() service.
 336                                       In blocking mode, it is ready for consumption
 337                                       when the call returns. In non-blocking mode,
 338                                       it is ready when WaitEvent is signaled.  The
 339                                       list of failed CPU is terminated by
 340                                       END_OF_CPU_LIST.
 341
 342   @retval EFI_SUCCESS             In blocking mode, all APs have finished before
 343                                   the timeout expired.
 344   @retval EFI_SUCCESS             In non-blocking mode, function has been dispatched
 345                                   to all enabled APs.
 346   @retval EFI_UNSUPPORTED         A non-blocking mode request was made after the
 347                                   UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was
 348                                   signaled.
 349   @retval EFI_DEVICE_ERROR        Caller processor is AP.
 350   @retval EFI_NOT_STARTED         No enabled APs exist in the system.
 351   @retval EFI_NOT_READY           Any enabled APs are busy.
 352   @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
 353                                   all enabled APs have finished.
 354   @retval EFI_INVALID_PARAMETER   Procedure is NULL.
 355
 356 **/
 357 typedef
 358 EFI_STATUS
 359 (EFIAPI *EFI_MP_SERVICES_STARTUP_ALL_APS)(
 360   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 361   IN  EFI_AP_PROCEDURE          Procedure,
 362   IN  BOOLEAN                   SingleThread,
 363   IN  EFI_EVENT                 WaitEvent               OPTIONAL,
 364   IN  UINTN                     TimeoutInMicroSeconds,
 365   IN  VOID                      *ProcedureArgument      OPTIONAL,
 366   OUT UINTN                     **FailedCpuList         OPTIONAL
 367   );
 368
 369 /**
 370   This service lets the caller get one enabled AP to execute a caller-provided
 371   function. The caller can request the BSP to either wait for the completion
 372   of the AP or just proceed with the next task by using the EFI event mechanism.
 373   See EFI_MP_SERVICES_PROTOCOL.StartupAllAPs() for more details on non-blocking
 374   execution support.  This service may only be called from the BSP.
 375
 376   This function is used to dispatch one enabled AP to the function specified by
 377   Procedure passing in the argument specified by ProcedureArgument.  If WaitEvent
 378   is NULL, execution is in blocking mode. The BSP waits until the AP finishes or
 379   TimeoutInMicroSecondss expires. Otherwise, execution is in non-blocking mode.
 380   BSP proceeds to the next task without waiting for the AP. If a non-blocking mode
 381   is requested after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT is signaled,
 382   then EFI_UNSUPPORTED must be returned.
 383
 384   If the timeout specified by TimeoutInMicroseconds expires before the AP returns
 385   from Procedure, then execution of Procedure by the AP is terminated. The AP is
 386   available for subsequent calls to EFI_MP_SERVICES_PROTOCOL.StartupAllAPs() and
 387   EFI_MP_SERVICES_PROTOCOL.StartupThisAP().
 388
 389   @param[in]  This                    A pointer to the EFI_MP_SERVICES_PROTOCOL
 390                                       instance.
 391   @param[in]  Procedure               A pointer to the function to be run on the
 392                                       designated AP of the system. See type
 393                                       EFI_AP_PROCEDURE.
 394   @param[in]  ProcessorNumber         The handle number of the AP. The range is
 395                                       from 0 to the total number of logical
 396                                       processors minus 1. The total number of
 397                                       logical processors can be retrieved by
 398                                       EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 399   @param[in]  WaitEvent               The event created by the caller with CreateEvent()
 400                                       service.  If it is NULL, then execute in
 401                                       blocking mode. BSP waits until this AP finish
 402                                       or TimeoutInMicroSeconds expires.  If it's
 403                                       not NULL, then execute in non-blocking mode.
 404                                       BSP requests the function specified by
 405                                       Procedure to be started on this AP,
 406                                       and go on executing immediately. If this AP
 407                                       return from Procedure or TimeoutInMicroSeconds
 408                                       expires, this event is signaled. The BSP
 409                                       can use the CheckEvent() or WaitForEvent()
 410                                       services to check the state of event.  Type
 411                                       EFI_EVENT is defined in CreateEvent() in
 412                                       the Unified Extensible Firmware Interface
 413                                       Specification.
 414   @param[in]  TimeoutInMicrosecsond   Indicates the time limit in microseconds for
 415                                       this AP to finish this Procedure, either for
 416                                       blocking or non-blocking mode. Zero means
 417                                       infinity.  If the timeout expires before
 418                                       this AP returns from Procedure, then Procedure
 419                                       on the AP is terminated. The
 420                                       AP is available for next function assigned
 421                                       by EFI_MP_SERVICES_PROTOCOL.StartupAllAPs()
 422                                       or EFI_MP_SERVICES_PROTOCOL.StartupThisAP().
 423                                       If the timeout expires in blocking mode,
 424                                       BSP returns EFI_TIMEOUT.  If the timeout
 425                                       expires in non-blocking mode, WaitEvent
 426                                       is signaled with SignalEvent().
 427   @param[in]  ProcedureArgument       The parameter passed into Procedure on the
 428                                       specified AP.
 429   @param[out] Finished                If NULL, this parameter is ignored.  In
 430                                       blocking mode, this parameter is ignored.
 431                                       In non-blocking mode, if AP returns from
 432                                       Procedure before the timeout expires, its
 433                                       content is set to TRUE. Otherwise, the
 434                                       value is set to FALSE. The caller can
 435                                       determine if the AP returned from Procedure
 436                                       by evaluating this value.
 437
 438   @retval EFI_SUCCESS             In blocking mode, specified AP finished before
 439                                   the timeout expires.
 440   @retval EFI_SUCCESS             In non-blocking mode, the function has been
 441                                   dispatched to specified AP.
 442   @retval EFI_UNSUPPORTED         A non-blocking mode request was made after the
 443                                   UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was
 444                                   signaled.
 445   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 446   @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
 447                                   the specified AP has finished.
 448   @retval EFI_NOT_READY           The specified AP is busy.
 449   @retval EFI_NOT_FOUND           The processor with the handle specified by
 450                                   ProcessorNumber does not exist.
 451   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the BSP or disabled AP.
 452   @retval EFI_INVALID_PARAMETER   Procedure is NULL.
 453
 454 **/
 455 typedef
 456 EFI_STATUS
 457 (EFIAPI *EFI_MP_SERVICES_STARTUP_THIS_AP)(
 458   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 459   IN  EFI_AP_PROCEDURE          Procedure,
 460   IN  UINTN                     ProcessorNumber,
 461   IN  EFI_EVENT                 WaitEvent               OPTIONAL,
 462   IN  UINTN                     TimeoutInMicroseconds,
 463   IN  VOID                      *ProcedureArgument      OPTIONAL,
 464   OUT BOOLEAN                   *Finished               OPTIONAL
 465   );
 466
 467 /**
 468   This service switches the requested AP to be the BSP from that point onward.
 469   This service changes the BSP for all purposes.   This call can only be performed
 470   by the current BSP.
 471
 472   This service switches the requested AP to be the BSP from that point onward.
 473   This service changes the BSP for all purposes. The new BSP can take over the
 474   execution of the old BSP and continue seamlessly from where the old one left
 475   off. This service may not be supported after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT
 476   is signaled.
 477
 478   If the BSP cannot be switched prior to the return from this service, then
 479   EFI_UNSUPPORTED must be returned.
 480
 481   @param[in] This              A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
 482   @param[in] ProcessorNumber   The handle number of AP that is to become the new
 483                                BSP. The range is from 0 to the total number of
 484                                logical processors minus 1. The total number of
 485                                logical processors can be retrieved by
 486                                EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 487   @param[in] EnableOldBSP      If TRUE, then the old BSP will be listed as an
 488                                enabled AP. Otherwise, it will be disabled.
 489
 490   @retval EFI_SUCCESS             BSP successfully switched.
 491   @retval EFI_UNSUPPORTED         Switching the BSP cannot be completed prior to
 492                                   this service returning.
 493   @retval EFI_UNSUPPORTED         Switching the BSP is not supported.
 494   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 495   @retval EFI_NOT_FOUND           The processor with the handle specified by
 496                                   ProcessorNumber does not exist.
 497   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the current BSP or
 498                                   a disabled AP.
 499   @retval EFI_NOT_READY           The specified AP is busy.
 500
 501 **/
 502 typedef
 503 EFI_STATUS
 504 (EFIAPI *EFI_MP_SERVICES_SWITCH_BSP)(
 505   IN EFI_MP_SERVICES_PROTOCOL  *This,
 506   IN  UINTN                    ProcessorNumber,
 507   IN  BOOLEAN                  EnableOldBSP
 508   );
 509
 510 /**
 511   This service lets the caller enable or disable an AP from this point onward.
 512   This service may only be called from the BSP.
 513
 514   This service allows the caller enable or disable an AP from this point onward.
 515   The caller can optionally specify the health status of the AP by Health. If
 516   an AP is being disabled, then the state of the disabled AP is implementation
 517   dependent. If an AP is enabled, then the implementation must guarantee that a
 518   complete initialization sequence is performed on the AP, so the AP is in a state
 519   that is compatible with an MP operating system. This service may not be supported
 520   after the UEFI Event EFI_EVENT_GROUP_READY_TO_BOOT is signaled.
 521
 522   If the enable or disable AP operation cannot be completed prior to the return
 523   from this service, then EFI_UNSUPPORTED must be returned.
 524
 525   @param[in] This              A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
 526   @param[in] ProcessorNumber   The handle number of AP.
 527                                The range is from 0 to the total number of
 528                                logical processors minus 1. The total number of
 529                                logical processors can be retrieved by
 530                                EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 531   @param[in] EnableAP          Specifies the new state for the processor for
 532                                enabled, FALSE for disabled.
 533   @param[in] HealthFlag        If not NULL, a pointer to a value that specifies
 534                                the new health status of the AP. This flag
 535                                corresponds to StatusFlag defined in
 536                                EFI_MP_SERVICES_PROTOCOL.GetProcessorInfo(). Only
 537                                the PROCESSOR_HEALTH_STATUS_BIT is used. All other
 538                                bits are ignored.  If it is NULL, this parameter
 539                                is ignored.
 540
 541   @retval EFI_SUCCESS             The specified AP was enabled or disabled successfully.
 542   @retval EFI_UNSUPPORTED         Enabling or disabling an AP cannot be completed
 543                                   prior to this service returning.
 544   @retval EFI_UNSUPPORTED         Enabling or disabling an AP is not supported.
 545   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 546   @retval EFI_NOT_FOUND           Processor with the handle specified by ProcessorNumber
 547                                   does not exist.
 548   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the BSP.
 549
 550 **/
 551 typedef
 552 EFI_STATUS
 553 (EFIAPI *EFI_MP_SERVICES_ENABLEDISABLEAP)(
 554   IN  EFI_MP_SERVICES_PROTOCOL  *This,
 555   IN  UINTN                     ProcessorNumber,
 556   IN  BOOLEAN                   EnableAP,
 557   IN  UINT32                    *HealthFlag OPTIONAL
 558   );
 559
 560 /**
 561   This return the handle number for the calling processor.  This service may be
 562   called from the BSP and APs.
 563
 564   This service returns the processor handle number for the calling processor.
 565   The returned value is in the range from 0 to the total number of logical
 566   processors minus 1. The total number of logical processors can be retrieved
 567   with EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors(). This service may be
 568   called from the BSP and APs. If ProcessorNumber is NULL, then EFI_INVALID_PARAMETER
 569   is returned. Otherwise, the current processors handle number is returned in
 570   ProcessorNumber, and EFI_SUCCESS is returned.
 571
 572   @param[in] This              A pointer to the EFI_MP_SERVICES_PROTOCOL instance.
 573   @param[in] ProcessorNumber   Pointer to the handle number of AP.
 574                                The range is from 0 to the total number of
 575                                logical processors minus 1. The total number of
 576                                logical processors can be retrieved by
 577                                EFI_MP_SERVICES_PROTOCOL.GetNumberOfProcessors().
 578
 579   @retval EFI_SUCCESS             The current processor handle number was returned
 580                                   in ProcessorNumber.
 581   @retval EFI_INVALID_PARAMETER   ProcessorNumber is NULL.
 582
 583 **/
 584 typedef
 585 EFI_STATUS
 586 (EFIAPI *EFI_MP_SERVICES_WHOAMI)(
 587   IN EFI_MP_SERVICES_PROTOCOL  *This,
 588   OUT UINTN                    *ProcessorNumber
 589   );
 590
 591 ///
 592 /// When installed, the MP Services Protocol produces a collection of services
 593 /// that are needed for MP management.
 594 ///
 595 /// Before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, the module
 596 /// that produces this protocol is required to place all APs into an idle state
 597 /// whenever the APs are disabled or the APs are not executing code as requested
 598 /// through the StartupAllAPs() or StartupThisAP() services. The idle state of
 599 /// an AP before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled is
 600 /// implementation dependent.
 601 ///
 602 /// After the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, all the APs
 603 /// must be placed in the OS compatible CPU state as defined by the UEFI
 604 /// Specification. Implementations of this protocol may use the UEFI event
 605 /// EFI_EVENT_GROUP_READY_TO_BOOT to force APs into the OS compatible state as
 606 /// defined by the UEFI Specification. Modules that use this protocol must
 607 /// guarantee that all non-blocking mode requests on all APs have been completed
 608 /// before the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled. Since the
 609 /// order that event notification functions in the same event group are executed
 610 /// is not deterministic, an event of type EFI_EVENT_GROUP_READY_TO_BOOT cannot
 611 /// be used to guarantee that APs have completed their non-blocking mode requests.
 612 ///
 613 /// When the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, the StartAllAPs()
 614 /// and StartupThisAp() services must no longer support non-blocking mode requests.
 615 /// The support for SwitchBSP() and EnableDisableAP() may no longer be supported
 616 /// after this event is signaled. Since UEFI Applications and UEFI OS Loaders
 617 /// execute after the UEFI event EFI_EVENT_GROUP_READY_TO_BOOT is signaled, these
 618 /// UEFI images must be aware that the functionality of this protocol may be reduced.
 619 ///
 620 struct _EFI_MP_SERVICES_PROTOCOL {
 621   EFI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS  GetNumberOfProcessors;
 622   EFI_MP_SERVICES_GET_PROCESSOR_INFO        GetProcessorInfo;
 623   EFI_MP_SERVICES_STARTUP_ALL_APS           StartupAllAPs;
 624   EFI_MP_SERVICES_STARTUP_THIS_AP           StartupThisAP;
 625   EFI_MP_SERVICES_SWITCH_BSP                SwitchBSP;
 626   EFI_MP_SERVICES_ENABLEDISABLEAP           EnableDisableAP;
 627   EFI_MP_SERVICES_WHOAMI                    WhoAmI;
 628 };
 629
 630 extern EFI_GUID gEfiMpServiceProtocolGuid;
 631
 632 #endif