UefiCpuPkg/Library/MpInitLib/DxeMpLib.c

   1 /** @file
   2   MP initialize support functions for DXE phase.
   3
   4   Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "MpLib.h"
  16
  17 #include <Library/UefiLib.h>
  18 #include <Library/UefiBootServicesTableLib.h>
  19 #include <Library/DebugAgentLib.h>
  20
  21 #define  AP_CHECK_INTERVAL     (EFI_TIMER_PERIOD_MILLISECONDS (100))
  22 #define  AP_SAFE_STACK_SIZE    128
  23
  24 CPU_MP_DATA      *mCpuMpData = NULL;
  25 EFI_EVENT        mCheckAllApsEvent = NULL;
  26 EFI_EVENT        mMpInitExitBootServicesEvent = NULL;
  27 EFI_EVENT        mLegacyBootEvent = NULL;
  28 volatile BOOLEAN mStopCheckAllApsStatus = TRUE;
  29 VOID             *mReservedApLoopFunc = NULL;
  30 UINTN            mReservedTopOfApStack;
  31 volatile UINT32  mNumberToFinish = 0;
  32
  33 /**
  34   Enable Debug Agent to support source debugging on AP function.
  35
  36 **/
  37 VOID
  38 EnableDebugAgent (
  39   VOID
  40   )
  41 {
  42   //
  43   // Initialize Debug Agent to support source level debug in DXE phase
  44   //
  45   InitializeDebugAgent (DEBUG_AGENT_INIT_DXE_AP, NULL, NULL);
  46 }
  47
  48 /**
  49   Get the pointer to CPU MP Data structure.
  50
  51   @return  The pointer to CPU MP Data structure.
  52 **/
  53 CPU_MP_DATA *
  54 GetCpuMpData (
  55   VOID
  56   )
  57 {
  58   ASSERT (mCpuMpData != NULL);
  59   return mCpuMpData;
  60 }
  61
  62 /**
  63   Save the pointer to CPU MP Data structure.
  64
  65   @param[in] CpuMpData  The pointer to CPU MP Data structure will be saved.
  66 **/
  67 VOID
  68 SaveCpuMpData (
  69   IN CPU_MP_DATA   *CpuMpData
  70   )
  71 {
  72   mCpuMpData = CpuMpData;
  73 }
  74
  75 /**
  76   Allocate reset vector buffer.
  77
  78   @param[in, out]  CpuMpData  The pointer to CPU MP Data structure.
  79 **/
  80 VOID
  81 AllocateResetVector (
  82   IN OUT CPU_MP_DATA          *CpuMpData
  83   )
  84 {
  85   EFI_STATUS            Status;
  86   UINTN                 ApResetVectorSize;
  87   EFI_PHYSICAL_ADDRESS  StartAddress;
  88
  89   if (CpuMpData->SaveRestoreFlag) {
  90     BackupAndPrepareWakeupBuffer (CpuMpData);
  91   } else {
  92     ApResetVectorSize = CpuMpData->AddressMap.RendezvousFunnelSize +
  93                         sizeof (MP_CPU_EXCHANGE_INFO);
  94
  95     StartAddress = BASE_1MB;
  96     Status = gBS->AllocatePages (
  97                     AllocateMaxAddress,
  98                     EfiACPIMemoryNVS,
  99                     EFI_SIZE_TO_PAGES (ApResetVectorSize),
 100                     &StartAddress
 101                     );
 102     ASSERT_EFI_ERROR (Status);
 103
 104     CpuMpData->WakeupBuffer      = (UINTN) StartAddress;
 105     CpuMpData->MpCpuExchangeInfo = (MP_CPU_EXCHANGE_INFO *) (UINTN)
 106                   (CpuMpData->WakeupBuffer + CpuMpData->AddressMap.RendezvousFunnelSize);
 107     //
 108     // copy AP reset code in it
 109     //
 110     CopyMem (
 111       (VOID *) CpuMpData->WakeupBuffer,
 112       (VOID *) CpuMpData->AddressMap.RendezvousFunnelAddress,
 113       CpuMpData->AddressMap.RendezvousFunnelSize
 114       );
 115   }
 116 }
 117
 118 /**
 119   Free AP reset vector buffer.
 120
 121   @param[in]  CpuMpData  The pointer to CPU MP Data structure.
 122 **/
 123 VOID
 124 FreeResetVector (
 125   IN CPU_MP_DATA              *CpuMpData
 126   )
 127 {
 128   EFI_STATUS            Status;
 129   UINTN                 ApResetVectorSize;
 130
 131   if (CpuMpData->SaveRestoreFlag) {
 132     RestoreWakeupBuffer (CpuMpData);
 133   } else {
 134     ApResetVectorSize = CpuMpData->AddressMap.RendezvousFunnelSize +
 135                         sizeof (MP_CPU_EXCHANGE_INFO);
 136     Status = gBS->FreePages(
 137                (EFI_PHYSICAL_ADDRESS)CpuMpData->WakeupBuffer,
 138                EFI_SIZE_TO_PAGES (ApResetVectorSize)
 139                );
 140     ASSERT_EFI_ERROR (Status);
 141   }
 142 }
 143
 144 /**
 145   Checks APs status and updates APs status if needed.
 146
 147 **/
 148 VOID
 149 CheckAndUpdateApsStatus (
 150   VOID
 151   )
 152 {
 153   UINTN                   ProcessorNumber;
 154   EFI_STATUS              Status;
 155   CPU_MP_DATA             *CpuMpData;
 156
 157   CpuMpData = GetCpuMpData ();
 158
 159   //
 160   // First, check whether pending StartupAllAPs() exists.
 161   //
 162   if (CpuMpData->WaitEvent != NULL) {
 163
 164     Status = CheckAllAPs ();
 165     //
 166     // If all APs finish for StartupAllAPs(), signal the WaitEvent for it.
 167     //
 168     if (Status != EFI_NOT_READY) {
 169       Status = gBS->SignalEvent (CpuMpData->WaitEvent);
 170       CpuMpData->WaitEvent = NULL;
 171     }
 172   }
 173
 174   //
 175   // Second, check whether pending StartupThisAPs() callings exist.
 176   //
 177   for (ProcessorNumber = 0; ProcessorNumber < CpuMpData->CpuCount; ProcessorNumber++) {
 178
 179     if (CpuMpData->CpuData[ProcessorNumber].WaitEvent == NULL) {
 180       continue;
 181     }
 182
 183     Status = CheckThisAP (ProcessorNumber);
 184
 185     if (Status != EFI_NOT_READY) {
 186       gBS->SignalEvent (CpuMpData->CpuData[ProcessorNumber].WaitEvent);
 187      CpuMpData->CpuData[ProcessorNumber].WaitEvent = NULL;
 188     }
 189   }
 190 }
 191
 192 /**
 193   Checks APs' status periodically.
 194
 195   This function is triggered by timer periodically to check the
 196   state of APs for StartupAllAPs() and StartupThisAP() executed
 197   in non-blocking mode.
 198
 199   @param[in]  Event    Event triggered.
 200   @param[in]  Context  Parameter passed with the event.
 201
 202 **/
 203 VOID
 204 EFIAPI
 205 CheckApsStatus (
 206   IN  EFI_EVENT                           Event,
 207   IN  VOID                                *Context
 208   )
 209 {
 210   //
 211   // If CheckApsStatus() is not stopped, otherwise return immediately.
 212   //
 213   if (!mStopCheckAllApsStatus) {
 214     CheckAndUpdateApsStatus ();
 215   }
 216 }
 217
 218 /**
 219   Get Protected mode code segment from current GDT table.
 220
 221   @return  Protected mode code segment value.
 222 **/
 223 UINT16
 224 GetProtectedModeCS (
 225   VOID
 226   )
 227 {
 228   IA32_DESCRIPTOR          GdtrDesc;
 229   IA32_SEGMENT_DESCRIPTOR  *GdtEntry;
 230   UINTN                    GdtEntryCount;
 231   UINT16                   Index;
 232
 233   Index = (UINT16) -1;
 234   AsmReadGdtr (&GdtrDesc);
 235   GdtEntryCount = (GdtrDesc.Limit + 1) / sizeof (IA32_SEGMENT_DESCRIPTOR);
 236   GdtEntry = (IA32_SEGMENT_DESCRIPTOR *) GdtrDesc.Base;
 237   for (Index = 0; Index < GdtEntryCount; Index++) {
 238     if (GdtEntry->Bits.L == 0) {
 239       if (GdtEntry->Bits.Type > 8 && GdtEntry->Bits.L == 0) {
 240         break;
 241       }
 242     }
 243     GdtEntry++;
 244   }
 245   ASSERT (Index != -1);
 246   return Index * 8;
 247 }
 248
 249 /**
 250   Do sync on APs.
 251
 252   @param[in, out] Buffer  Pointer to private data buffer.
 253 **/
 254 VOID
 255 EFIAPI
 256 RelocateApLoop (
 257   IN OUT VOID  *Buffer
 258   )
 259 {
 260   CPU_MP_DATA            *CpuMpData;
 261   BOOLEAN                MwaitSupport;
 262   ASM_RELOCATE_AP_LOOP   AsmRelocateApLoopFunc;
 263   UINTN                  ProcessorNumber;
 264
 265   MpInitLibWhoAmI (&ProcessorNumber);
 266   CpuMpData    = GetCpuMpData ();
 267   MwaitSupport = IsMwaitSupport ();
 268   AsmRelocateApLoopFunc = (ASM_RELOCATE_AP_LOOP) (UINTN) mReservedApLoopFunc;
 269   AsmRelocateApLoopFunc (
 270     MwaitSupport,
 271     CpuMpData->ApTargetCState,
 272     CpuMpData->PmCodeSegment,
 273     mReservedTopOfApStack - ProcessorNumber * AP_SAFE_STACK_SIZE,
 274     (UINTN) &mNumberToFinish
 275     );
 276   //
 277   // It should never reach here
 278   //
 279   ASSERT (FALSE);
 280 }
 281
 282 /**
 283   Callback function for ExitBootServices.
 284
 285   @param[in]  Event             Event whose notification function is being invoked.
 286   @param[in]  Context           The pointer to the notification function's context,
 287                                 which is implementation-dependent.
 288
 289 **/
 290 VOID
 291 EFIAPI
 292 MpInitChangeApLoopCallback (
 293   IN EFI_EVENT                Event,
 294   IN VOID                     *Context
 295   )
 296 {
 297   CPU_MP_DATA               *CpuMpData;
 298
 299   CpuMpData = GetCpuMpData ();
 300   CpuMpData->SaveRestoreFlag = TRUE;
 301   CpuMpData->PmCodeSegment = GetProtectedModeCS ();
 302   CpuMpData->ApLoopMode = PcdGet8 (PcdCpuApLoopMode);
 303   mNumberToFinish = CpuMpData->CpuCount - 1;
 304   WakeUpAP (CpuMpData, TRUE, 0, RelocateApLoop, NULL);
 305   while (mNumberToFinish > 0) {
 306     CpuPause ();
 307   }
 308   DEBUG ((DEBUG_INFO, "%a() done!\n", __FUNCTION__));
 309 }
 310
 311 /**
 312   Initialize global data for MP support.
 313
 314   @param[in] CpuMpData  The pointer to CPU MP Data structure.
 315 **/
 316 VOID
 317 InitMpGlobalData (
 318   IN CPU_MP_DATA               *CpuMpData
 319   )
 320 {
 321   EFI_STATUS                 Status;
 322   EFI_PHYSICAL_ADDRESS       Address;
 323   UINTN                      ApSafeBufferSize;
 324
 325   SaveCpuMpData (CpuMpData);
 326
 327   if (CpuMpData->CpuCount == 1) {
 328     //
 329     // If only BSP exists, return
 330     //
 331     return;
 332   }
 333
 334   //
 335   // Avoid APs access invalid buffer data which allocated by BootServices,
 336   // so we will allocate reserved data for AP loop code. We also need to
 337   // allocate this buffer below 4GB due to APs may be transferred to 32bit
 338   // protected mode on long mode DXE.
 339   // Allocating it in advance since memory services are not available in
 340   // Exit Boot Services callback function.
 341   //
 342   ApSafeBufferSize  = CpuMpData->AddressMap.RelocateApLoopFuncSize;
 343   ApSafeBufferSize += CpuMpData->CpuCount * AP_SAFE_STACK_SIZE;
 344
 345   Address = BASE_4GB - 1;
 346   Status  = gBS->AllocatePages (
 347                    AllocateMaxAddress,
 348                    EfiReservedMemoryType,
 349                    EFI_SIZE_TO_PAGES (ApSafeBufferSize),
 350                    &Address
 351                    );
 352   ASSERT_EFI_ERROR (Status);
 353   mReservedApLoopFunc = (VOID *) (UINTN) Address;
 354   ASSERT (mReservedApLoopFunc != NULL);
 355   mReservedTopOfApStack = (UINTN) Address + EFI_PAGES_TO_SIZE (EFI_SIZE_TO_PAGES (ApSafeBufferSize));
 356   ASSERT ((mReservedTopOfApStack & (UINTN)(CPU_STACK_ALIGNMENT - 1)) == 0);
 357   CopyMem (
 358     mReservedApLoopFunc,
 359     CpuMpData->AddressMap.RelocateApLoopFuncAddress,
 360     CpuMpData->AddressMap.RelocateApLoopFuncSize
 361     );
 362
 363   Status = gBS->CreateEvent (
 364                   EVT_TIMER | EVT_NOTIFY_SIGNAL,
 365                   TPL_NOTIFY,
 366                   CheckApsStatus,
 367                   NULL,
 368                   &mCheckAllApsEvent
 369                   );
 370   ASSERT_EFI_ERROR (Status);
 371
 372   //
 373   // Set timer to check all APs status.
 374   //
 375   Status = gBS->SetTimer (
 376                   mCheckAllApsEvent,
 377                   TimerPeriodic,
 378                   AP_CHECK_INTERVAL
 379                   );
 380   ASSERT_EFI_ERROR (Status);
 381
 382   Status = gBS->CreateEvent (
 383                   EVT_SIGNAL_EXIT_BOOT_SERVICES,
 384                   TPL_CALLBACK,
 385                   MpInitChangeApLoopCallback,
 386                   NULL,
 387                   &mMpInitExitBootServicesEvent
 388                   );
 389   ASSERT_EFI_ERROR (Status);
 390
 391   Status = gBS->CreateEventEx (
 392                   EVT_NOTIFY_SIGNAL,
 393                   TPL_CALLBACK,
 394                   MpInitChangeApLoopCallback,
 395                   NULL,
 396                   &gEfiEventLegacyBootGuid,
 397                   &mLegacyBootEvent
 398                   );
 399   ASSERT_EFI_ERROR (Status);
 400 }
 401
 402 /**
 403   This service executes a caller provided function on all enabled APs.
 404
 405   @param[in]  Procedure               A pointer to the function to be run on
 406                                       enabled APs of the system. See type
 407                                       EFI_AP_PROCEDURE.
 408   @param[in]  SingleThread            If TRUE, then all the enabled APs execute
 409                                       the function specified by Procedure one by
 410                                       one, in ascending order of processor handle
 411                                       number.  If FALSE, then all the enabled APs
 412                                       execute the function specified by Procedure
 413                                       simultaneously.
 414   @param[in]  WaitEvent               The event created by the caller with CreateEvent()
 415                                       service.  If it is NULL, then execute in
 416                                       blocking mode. BSP waits until all APs finish
 417                                       or TimeoutInMicroSeconds expires.  If it's
 418                                       not NULL, then execute in non-blocking mode.
 419                                       BSP requests the function specified by
 420                                       Procedure to be started on all the enabled
 421                                       APs, and go on executing immediately. If
 422                                       all return from Procedure, or TimeoutInMicroSeconds
 423                                       expires, this event is signaled. The BSP
 424                                       can use the CheckEvent() or WaitForEvent()
 425                                       services to check the state of event.  Type
 426                                       EFI_EVENT is defined in CreateEvent() in
 427                                       the Unified Extensible Firmware Interface
 428                                       Specification.
 429   @param[in]  TimeoutInMicroseconds   Indicates the time limit in microseconds for
 430                                       APs to return from Procedure, either for
 431                                       blocking or non-blocking mode. Zero means
 432                                       infinity.  If the timeout expires before
 433                                       all APs return from Procedure, then Procedure
 434                                       on the failed APs is terminated. All enabled
 435                                       APs are available for next function assigned
 436                                       by MpInitLibStartupAllAPs() or
 437                                       MPInitLibStartupThisAP().
 438                                       If the timeout expires in blocking mode,
 439                                       BSP returns EFI_TIMEOUT.  If the timeout
 440                                       expires in non-blocking mode, WaitEvent
 441                                       is signaled with SignalEvent().
 442   @param[in]  ProcedureArgument       The parameter passed into Procedure for
 443                                       all APs.
 444   @param[out] FailedCpuList           If NULL, this parameter is ignored. Otherwise,
 445                                       if all APs finish successfully, then its
 446                                       content is set to NULL. If not all APs
 447                                       finish before timeout expires, then its
 448                                       content is set to address of the buffer
 449                                       holding handle numbers of the failed APs.
 450                                       The buffer is allocated by MP Initialization
 451                                       library, and it's the caller's responsibility to
 452                                       free the buffer with FreePool() service.
 453                                       In blocking mode, it is ready for consumption
 454                                       when the call returns. In non-blocking mode,
 455                                       it is ready when WaitEvent is signaled.  The
 456                                       list of failed CPU is terminated by
 457                                       END_OF_CPU_LIST.
 458
 459   @retval EFI_SUCCESS             In blocking mode, all APs have finished before
 460                                   the timeout expired.
 461   @retval EFI_SUCCESS             In non-blocking mode, function has been dispatched
 462                                   to all enabled APs.
 463   @retval EFI_UNSUPPORTED         A non-blocking mode request was made after the
 464                                   UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was
 465                                   signaled.
 466   @retval EFI_UNSUPPORTED         WaitEvent is not NULL if non-blocking mode is not
 467                                   supported.
 468   @retval EFI_DEVICE_ERROR        Caller processor is AP.
 469   @retval EFI_NOT_STARTED         No enabled APs exist in the system.
 470   @retval EFI_NOT_READY           Any enabled APs are busy.
 471   @retval EFI_NOT_READY           MP Initialize Library is not initialized.
 472   @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
 473                                   all enabled APs have finished.
 474   @retval EFI_INVALID_PARAMETER   Procedure is NULL.
 475
 476 **/
 477 EFI_STATUS
 478 EFIAPI
 479 MpInitLibStartupAllAPs (
 480   IN  EFI_AP_PROCEDURE          Procedure,
 481   IN  BOOLEAN                   SingleThread,
 482   IN  EFI_EVENT                 WaitEvent               OPTIONAL,
 483   IN  UINTN                     TimeoutInMicroseconds,
 484   IN  VOID                      *ProcedureArgument      OPTIONAL,
 485   OUT UINTN                     **FailedCpuList         OPTIONAL
 486   )
 487 {
 488   EFI_STATUS              Status;
 489
 490   //
 491   // Temporarily stop checkAllApsStatus for avoid resource dead-lock.
 492   //
 493   mStopCheckAllApsStatus = TRUE;
 494
 495   Status = StartupAllAPsWorker (
 496              Procedure,
 497              SingleThread,
 498              WaitEvent,
 499              TimeoutInMicroseconds,
 500              ProcedureArgument,
 501              FailedCpuList
 502              );
 503
 504   //
 505   // Start checkAllApsStatus
 506   //
 507   mStopCheckAllApsStatus = FALSE;
 508
 509   return Status;
 510 }
 511
 512 /**
 513   This service lets the caller get one enabled AP to execute a caller-provided
 514   function.
 515
 516   @param[in]  Procedure               A pointer to the function to be run on the
 517                                       designated AP of the system. See type
 518                                       EFI_AP_PROCEDURE.
 519   @param[in]  ProcessorNumber         The handle number of the AP. The range is
 520                                       from 0 to the total number of logical
 521                                       processors minus 1. The total number of
 522                                       logical processors can be retrieved by
 523                                       MpInitLibGetNumberOfProcessors().
 524   @param[in]  WaitEvent               The event created by the caller with CreateEvent()
 525                                       service.  If it is NULL, then execute in
 526                                       blocking mode. BSP waits until this AP finish
 527                                       or TimeoutInMicroSeconds expires.  If it's
 528                                       not NULL, then execute in non-blocking mode.
 529                                       BSP requests the function specified by
 530                                       Procedure to be started on this AP,
 531                                       and go on executing immediately. If this AP
 532                                       return from Procedure or TimeoutInMicroSeconds
 533                                       expires, this event is signaled. The BSP
 534                                       can use the CheckEvent() or WaitForEvent()
 535                                       services to check the state of event.  Type
 536                                       EFI_EVENT is defined in CreateEvent() in
 537                                       the Unified Extensible Firmware Interface
 538                                       Specification.
 539   @param[in]  TimeoutInMicroseconds   Indicates the time limit in microseconds for
 540                                       this AP to finish this Procedure, either for
 541                                       blocking or non-blocking mode. Zero means
 542                                       infinity.  If the timeout expires before
 543                                       this AP returns from Procedure, then Procedure
 544                                       on the AP is terminated. The
 545                                       AP is available for next function assigned
 546                                       by MpInitLibStartupAllAPs() or
 547                                       MpInitLibStartupThisAP().
 548                                       If the timeout expires in blocking mode,
 549                                       BSP returns EFI_TIMEOUT.  If the timeout
 550                                       expires in non-blocking mode, WaitEvent
 551                                       is signaled with SignalEvent().
 552   @param[in]  ProcedureArgument       The parameter passed into Procedure on the
 553                                       specified AP.
 554   @param[out] Finished                If NULL, this parameter is ignored.  In
 555                                       blocking mode, this parameter is ignored.
 556                                       In non-blocking mode, if AP returns from
 557                                       Procedure before the timeout expires, its
 558                                       content is set to TRUE. Otherwise, the
 559                                       value is set to FALSE. The caller can
 560                                       determine if the AP returned from Procedure
 561                                       by evaluating this value.
 562
 563   @retval EFI_SUCCESS             In blocking mode, specified AP finished before
 564                                   the timeout expires.
 565   @retval EFI_SUCCESS             In non-blocking mode, the function has been
 566                                   dispatched to specified AP.
 567   @retval EFI_UNSUPPORTED         A non-blocking mode request was made after the
 568                                   UEFI event EFI_EVENT_GROUP_READY_TO_BOOT was
 569                                   signaled.
 570   @retval EFI_UNSUPPORTED         WaitEvent is not NULL if non-blocking mode is not
 571                                   supported.
 572   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 573   @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
 574                                   the specified AP has finished.
 575   @retval EFI_NOT_READY           The specified AP is busy.
 576   @retval EFI_NOT_READY           MP Initialize Library is not initialized.
 577   @retval EFI_NOT_FOUND           The processor with the handle specified by
 578                                   ProcessorNumber does not exist.
 579   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the BSP or disabled AP.
 580   @retval EFI_INVALID_PARAMETER   Procedure is NULL.
 581
 582 **/
 583 EFI_STATUS
 584 EFIAPI
 585 MpInitLibStartupThisAP (
 586   IN  EFI_AP_PROCEDURE          Procedure,
 587   IN  UINTN                     ProcessorNumber,
 588   IN  EFI_EVENT                 WaitEvent               OPTIONAL,
 589   IN  UINTN                     TimeoutInMicroseconds,
 590   IN  VOID                      *ProcedureArgument      OPTIONAL,
 591   OUT BOOLEAN                   *Finished               OPTIONAL
 592   )
 593 {
 594   EFI_STATUS              Status;
 595
 596   //
 597   // temporarily stop checkAllApsStatus for avoid resource dead-lock.
 598   //
 599   mStopCheckAllApsStatus = TRUE;
 600
 601   Status = StartupThisAPWorker (
 602              Procedure,
 603              ProcessorNumber,
 604              WaitEvent,
 605              TimeoutInMicroseconds,
 606              ProcedureArgument,
 607              Finished
 608              );
 609
 610   mStopCheckAllApsStatus = FALSE;
 611
 612   return Status;
 613 }
 614
 615 /**
 616   This service switches the requested AP to be the BSP from that point onward.
 617   This service changes the BSP for all purposes. This call can only be performed
 618   by the current BSP.
 619
 620   @param[in] ProcessorNumber   The handle number of AP that is to become the new
 621                                BSP. The range is from 0 to the total number of
 622                                logical processors minus 1. The total number of
 623                                logical processors can be retrieved by
 624                                MpInitLibGetNumberOfProcessors().
 625   @param[in] EnableOldBSP      If TRUE, then the old BSP will be listed as an
 626                                enabled AP. Otherwise, it will be disabled.
 627
 628   @retval EFI_SUCCESS             BSP successfully switched.
 629   @retval EFI_UNSUPPORTED         Switching the BSP cannot be completed prior to
 630                                   this service returning.
 631   @retval EFI_UNSUPPORTED         Switching the BSP is not supported.
 632   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 633   @retval EFI_NOT_FOUND           The processor with the handle specified by
 634                                   ProcessorNumber does not exist.
 635   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the current BSP or
 636                                   a disabled AP.
 637   @retval EFI_NOT_READY           The specified AP is busy.
 638   @retval EFI_NOT_READY           MP Initialize Library is not initialized.
 639
 640 **/
 641 EFI_STATUS
 642 EFIAPI
 643 MpInitLibSwitchBSP (
 644   IN UINTN                     ProcessorNumber,
 645   IN BOOLEAN                   EnableOldBSP
 646   )
 647 {
 648   EFI_STATUS            Status;
 649   BOOLEAN               OldInterruptState;
 650
 651   //
 652   // Before send both BSP and AP to a procedure to exchange their roles,
 653   // interrupt must be disabled. This is because during the exchange role
 654   // process, 2 CPU may use 1 stack. If interrupt happens, the stack will
 655   // be corrupted, since interrupt return address will be pushed to stack
 656   // by hardware.
 657   //
 658   OldInterruptState = SaveAndDisableInterrupts ();
 659
 660   //
 661   // Mask LINT0 & LINT1 for the old BSP
 662   //
 663   DisableLvtInterrupts ();
 664
 665   Status = SwitchBSPWorker (ProcessorNumber, EnableOldBSP);
 666
 667   //
 668   // Restore interrupt state.
 669   //
 670   SetInterruptState (OldInterruptState);
 671
 672   return Status;
 673 }
 674
 675 /**
 676   This service lets the caller enable or disable an AP from this point onward.
 677   This service may only be called from the BSP.
 678
 679   @param[in] ProcessorNumber   The handle number of AP.
 680                                The range is from 0 to the total number of
 681                                logical processors minus 1. The total number of
 682                                logical processors can be retrieved by
 683                                MpInitLibGetNumberOfProcessors().
 684   @param[in] EnableAP          Specifies the new state for the processor for
 685                                enabled, FALSE for disabled.
 686   @param[in] HealthFlag        If not NULL, a pointer to a value that specifies
 687                                the new health status of the AP. This flag
 688                                corresponds to StatusFlag defined in
 689                                EFI_MP_SERVICES_PROTOCOL.GetProcessorInfo(). Only
 690                                the PROCESSOR_HEALTH_STATUS_BIT is used. All other
 691                                bits are ignored.  If it is NULL, this parameter
 692                                is ignored.
 693
 694   @retval EFI_SUCCESS             The specified AP was enabled or disabled successfully.
 695   @retval EFI_UNSUPPORTED         Enabling or disabling an AP cannot be completed
 696                                   prior to this service returning.
 697   @retval EFI_UNSUPPORTED         Enabling or disabling an AP is not supported.
 698   @retval EFI_DEVICE_ERROR        The calling processor is an AP.
 699   @retval EFI_NOT_FOUND           Processor with the handle specified by ProcessorNumber
 700                                   does not exist.
 701   @retval EFI_INVALID_PARAMETER   ProcessorNumber specifies the BSP.
 702   @retval EFI_NOT_READY           MP Initialize Library is not initialized.
 703
 704 **/
 705 EFI_STATUS
 706 EFIAPI
 707 MpInitLibEnableDisableAP (
 708   IN  UINTN                     ProcessorNumber,
 709   IN  BOOLEAN                   EnableAP,
 710   IN  UINT32                    *HealthFlag OPTIONAL
 711   )
 712 {
 713   EFI_STATUS     Status;
 714   BOOLEAN        TempStopCheckState;
 715
 716   TempStopCheckState = FALSE;
 717   //
 718   // temporarily stop checkAllAPsStatus for initialize parameters.
 719   //
 720   if (!mStopCheckAllApsStatus) {
 721     mStopCheckAllApsStatus = TRUE;
 722     TempStopCheckState     = TRUE;
 723   }
 724
 725   Status = EnableDisableApWorker (ProcessorNumber, EnableAP, HealthFlag);
 726
 727   if (TempStopCheckState) {
 728     mStopCheckAllApsStatus = FALSE;
 729   }
 730
 731   return Status;
 732 }