1 /*++ 2 3 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR> 4 Portions copyright (c) 2008 - 2009, Apple Inc. 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 16 #include "Host.h" 17 18 19 /** 20 Transfers control to a function starting with a new stack. 21 22 Transfers control to the function specified by EntryPoint using the new stack 23 specified by NewStack and passing in the parameters specified by Context1 and 24 Context2. Context1 and Context2 are optional and may be NULL. The function 25 EntryPoint must never return. 26 27 If EntryPoint is NULL, then ASSERT(). 28 If NewStack is NULL, then ASSERT(). 29 30 @param EntryPoint A pointer to function to call with the new stack. 31 @param Context1 A pointer to the context to pass into the EntryPoint 32 function. 33 @param Context2 A pointer to the context to pass into the EntryPoint 34 function. 35 @param NewStack A pointer to the new stack to use for the EntryPoint 36 function. 37 38 **/ 39 VOID 40 EFIAPI 41 PeiSwitchStacks ( 42 IN SWITCH_STACK_ENTRY_POINT EntryPoint, 43 IN VOID *Context1, OPTIONAL 44 IN VOID *Context2, OPTIONAL 45 IN VOID *NewStack 46 ) 47 { 48 BASE_LIBRARY_JUMP_BUFFER JumpBuffer; 49 50 ASSERT (EntryPoint != NULL); 51 ASSERT (NewStack != NULL); 52 53 // 54 // Stack should be aligned with CPU_STACK_ALIGNMENT 55 // 56 ASSERT (((UINTN)NewStack & (CPU_STACK_ALIGNMENT - 1)) == 0); 57 58 JumpBuffer.Eip = (UINTN)EntryPoint; 59 JumpBuffer.Esp = (UINTN)NewStack - sizeof (VOID*); 60 JumpBuffer.Esp -= sizeof (Context1) + sizeof (Context2); 61 ((VOID**)JumpBuffer.Esp)[1] = Context1; 62 ((VOID**)JumpBuffer.Esp)[2] = Context2; 63 64 LongJump (&JumpBuffer, (UINTN)-1); 65 66 67 // 68 // PeiSwitchStacks () will never return 69 // 70 ASSERT (FALSE); 71 } 72 73 74 75
