OvmfPkg/Sec/X64/SwitchStack.c

   1 /** @file
   2   Switch Stack functions.
   3
   4   Copyright (c) 2006 - 2007, Intel Corporation<BR>
   5   All rights reserved. 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 //
  16 // Include common header file for this module.
  17 //
  18
  19
  20 #include <Library/BaseLib.h>
  21 #include <Library/BaseMemoryLib.h>
  22 #include <Library/DebugLib.h>
  23 #include <Library/PeiServicesLib.h>
  24
  25 //
  26 // Type define for PEI Core Entry Point function
  27 //
  28 typedef
  29 VOID
  30 (EFIAPI *PEI_CORE_ENTRY_POINT)(
  31   IN CONST EFI_SEC_PEI_HAND_OFF        *SecCoreData,
  32   IN CONST EFI_PEI_PPI_DESCRIPTOR      *PpiList,
  33   IN VOID                              *Data
  34   )
  35 ;
  36
  37 /**
  38   Transfers control to a function starting with a new stack.
  39
  40   Transfers control to the function specified by EntryPoint using the new stack
  41   specified by NewStack and passing in the parameters specified by Context1 and
  42   Context2. Context1 and Context2 are optional and may be NULL. The function
  43   EntryPoint must never return.
  44
  45   If EntryPoint is NULL, then ASSERT().
  46   If NewStack is NULL, then ASSERT().
  47
  48   @param  EntryPoint  A pointer to function to call with the new stack.
  49   @param  Context1    A pointer to the context to pass into the EntryPoint
  50                       function.
  51   @param  Context2    A pointer to the context to pass into the EntryPoint
  52                       function.
  53   @param  NewStack    A pointer to the new stack to use for the EntryPoint
  54                       function.
  55   @param  NewBsp      A pointer to the new BSP for the EntryPoint on IPF. It's
  56                       Reserved on other architectures.
  57
  58 **/
  59 VOID
  60 EFIAPI
  61 PeiSwitchStacks (
  62   IN      SWITCH_STACK_ENTRY_POINT  EntryPoint,
  63   IN      VOID                      *Context1,  OPTIONAL
  64   IN      VOID                      *Context2,  OPTIONAL
  65   IN      VOID                      *Context3,  OPTIONAL
  66   IN      VOID                      *OldTopOfStack,
  67   IN      VOID                      *NewStack
  68   )
  69 {
  70   BASE_LIBRARY_JUMP_BUFFER  JumpBuffer;
  71   UINTN                     SizeOfStackUsed;
  72   UINTN                     SetJumpFlag;
  73
  74   ASSERT (EntryPoint != NULL);
  75   ASSERT (NewStack != NULL);
  76
  77   SetJumpFlag = SetJump (&JumpBuffer);
  78   //
  79   // The initial call to SetJump() must always return 0.
  80   // Subsequent calls to LongJump() may cause a non-zero value to be returned by SetJump().
  81   //
  82   if (SetJumpFlag == 0) {
  83     //
  84     // Stack should be aligned with CPU_STACK_ALIGNMENT
  85     //
  86     ASSERT (((UINTN)NewStack & (CPU_STACK_ALIGNMENT - 1)) == 0);
  87
  88     //JumpBuffer.Rip = (UINTN)EntryPoint;
  89     SizeOfStackUsed = (UINTN)OldTopOfStack - JumpBuffer.Rsp;
  90     JumpBuffer.Rsp = (UINTN)NewStack - SizeOfStackUsed;
  91     MemoryFence ();
  92     CopyMem (
  93       (VOID*) ((UINTN)NewStack - SizeOfStackUsed),
  94       (VOID*) ((UINTN)OldTopOfStack - SizeOfStackUsed),
  95       SizeOfStackUsed
  96       );
  97     LongJump (&JumpBuffer, (UINTN)-1);
  98   } else {
  99     (*(PEI_CORE_ENTRY_POINT)(EntryPoint)) (
 100       (EFI_SEC_PEI_HAND_OFF *) Context1,
 101       (EFI_PEI_PPI_DESCRIPTOR *) Context2,
 102       Context3
 103       );
 104   }
 105
 106   //
 107   // InternalSwitchStack () will never return
 108   //
 109   ASSERT (FALSE);
 110 }
 111
 112 /**
 113   Transfers control to a function starting with a new stack.
 114
 115   Transfers control to the function specified by EntryPoint using the new stack
 116   specified by NewStack and passing in the parameters specified by Context1 and
 117   Context2. Context1 and Context2 are optional and may be NULL. The function
 118   EntryPoint must never return.
 119
 120   If EntryPoint is NULL, then ASSERT().
 121   If NewStack is NULL, then ASSERT().
 122
 123   @param  EntryPoint  A pointer to function to call with the new stack.
 124   @param  Context1    A pointer to the context to pass into the EntryPoint
 125                       function.
 126   @param  Context2    A pointer to the context to pass into the EntryPoint
 127                       function.
 128   @param  NewStack    A pointer to the new stack to use for the EntryPoint
 129                       function.
 130   @param  NewBsp      A pointer to the new BSP for the EntryPoint on IPF. It's
 131                       Reserved on other architectures.
 132
 133 **/
 134 VOID
 135 EFIAPI
 136 SecSwitchStack (
 137   IN UINTN   TemporaryMemoryBase,
 138   IN UINTN   PermanentMemoryBase,
 139   IN UINTN   CopySize
 140   )
 141 {
 142   BASE_LIBRARY_JUMP_BUFFER  JumpBuffer;
 143   UINTN                     SetJumpFlag;
 144
 145   ASSERT ((VOID*)TemporaryMemoryBase != NULL);
 146   ASSERT ((VOID*)PermanentMemoryBase != NULL);
 147
 148   SetJumpFlag = SetJump (&JumpBuffer);
 149   //
 150   // The initial call to SetJump() must always return 0.
 151   // Subsequent calls to LongJump() may cause a non-zero value to be returned by SetJump().
 152   //
 153   if (SetJumpFlag == 0) {
 154     DEBUG ((EFI_D_ERROR, "SecSwitchStack+%d: Rsp: 0x%xL\n", __LINE__, JumpBuffer.Rsp));
 155     JumpBuffer.Rsp =
 156       (INTN)JumpBuffer.Rsp -
 157       (INTN)TemporaryMemoryBase +
 158       (INTN)PermanentMemoryBase;
 159     MemoryFence ();
 160     CopyMem((VOID*)PermanentMemoryBase, (VOID*)TemporaryMemoryBase, CopySize);
 161     LongJump (&JumpBuffer, (UINTN)-1);
 162   }
 163
 164 }
 165