UefiCpuPkg/CpuDxe/CpuMp.c

   1 /** @file
   2   CPU DXE Module.
   3
   4   Copyright (c) 2008 - 2014, 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 "CpuDxe.h"
  16 #include "CpuMp.h"
  17
  18 UINTN gMaxLogicalProcessorNumber;
  19 UINTN gApStackSize;
  20
  21 VOID *mCommonStack = 0;
  22 VOID *mTopOfApCommonStack = 0;
  23 VOID *mApStackStart = 0;
  24
  25 volatile UINTN mNumberOfProcessors;
  26
  27 EFI_MP_SERVICES_PROTOCOL  mMpServicesTemplate = {
  28   NULL, // GetNumberOfProcessors,
  29   NULL, // GetProcessorInfo,
  30   NULL, // StartupAllAPs,
  31   NULL, // StartupThisAP,
  32   NULL, // SwitchBSP,
  33   NULL, // EnableDisableAP,
  34   NULL  // WhoAmI
  35 };
  36
  37 /**
  38   Application Processors do loop routine
  39   after switch to its own stack.
  40
  41   @param  Context1    A pointer to the context to pass into the function.
  42   @param  Context2    A pointer to the context to pass into the function.
  43
  44 **/
  45 VOID
  46 ProcessorToIdleState (
  47   IN      VOID                      *Context1,  OPTIONAL
  48   IN      VOID                      *Context2   OPTIONAL
  49   )
  50 {
  51   DEBUG ((DEBUG_INFO, "Ap apicid is %d\n", GetApicId ()));
  52
  53   AsmApDoneWithCommonStack ();
  54
  55   CpuSleep ();
  56   CpuDeadLoop ();
  57 }
  58
  59 /**
  60   Application Processor C code entry point.
  61
  62 **/
  63 VOID
  64 EFIAPI
  65 ApEntryPointInC (
  66   VOID
  67   )
  68 {
  69   mNumberOfProcessors++;
  70   mApStackStart = (UINT8*)mApStackStart + gApStackSize;
  71
  72   SwitchStack (
  73     (SWITCH_STACK_ENTRY_POINT)(UINTN)ProcessorToIdleState,
  74     NULL,
  75     NULL,
  76     mApStackStart);
  77 }
  78
  79
  80 /**
  81   Initialize Multi-processor support.
  82
  83 **/
  84 VOID
  85 InitializeMpSupport (
  86   VOID
  87   )
  88 {
  89   gMaxLogicalProcessorNumber = (UINTN) PcdGet32 (PcdCpuMaxLogicalProcessorNumber);
  90   if (gMaxLogicalProcessorNumber < 1) {
  91     DEBUG ((DEBUG_ERROR, "Setting PcdCpuMaxLogicalProcessorNumber should be more than zero.\n"));
  92     return;
  93   }
  94
  95   if (gMaxLogicalProcessorNumber == 1) {
  96     return;
  97   }
  98
  99   gApStackSize = (UINTN) PcdGet32 (PcdCpuApStackSize);
 100   ASSERT ((gApStackSize & (SIZE_4KB - 1)) == 0);
 101
 102   mApStackStart = AllocatePages (EFI_SIZE_TO_PAGES (gMaxLogicalProcessorNumber * gApStackSize));
 103   ASSERT (mApStackStart != NULL);
 104
 105   //
 106   // the first buffer of stack size used for common stack, when the amount of AP
 107   // more than 1, we should never free the common stack which maybe used for AP reset.
 108   //
 109   mCommonStack = mApStackStart;
 110   mTopOfApCommonStack = (UINT8*) mApStackStart + gApStackSize;
 111   mApStackStart = mTopOfApCommonStack;
 112
 113   mNumberOfProcessors = 1;
 114
 115   if (mNumberOfProcessors == 1) {
 116     FreePages (mCommonStack, EFI_SIZE_TO_PAGES (gMaxLogicalProcessorNumber * gApStackSize));
 117     return;
 118   }
 119
 120   if (mNumberOfProcessors < gMaxLogicalProcessorNumber) {
 121     FreePages (mApStackStart, EFI_SIZE_TO_PAGES ((gMaxLogicalProcessorNumber - mNumberOfProcessors) *
 122                                                  gApStackSize));
 123   }
 124 }