1 #------------------------------------------------------------------------------ 2 # 3 # Copyright (c) 2007, Intel Corporation. All rights reserved.<BR> 4 # This program and the accompanying materials 5 # are licensed and made available under the terms and conditions of the BSD License 6 # which accompanies this distribution. The full text of the license may be found at 7 # http:#opensource.org/licenses/bsd-license.php 8 # 9 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 10 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 11 # 12 # Module Name: 13 # 14 # Stack.asm 15 # 16 # Abstract: 17 # 18 # Switch the stack from temporary memory to permenent memory. 19 # 20 #------------------------------------------------------------------------------ 21 22 .text 23 24 25 //------------------------------------------------------------------------------ 26 // VOID 27 // EFIAPI 28 // SecSwitchStack ( 29 // UINT32 TemporaryMemoryBase, 30 // UINT32 PermenentMemoryBase 31 // )// 32 //------------------------------------------------------------------------------ 33 ASM_GLOBAL ASM_PFX(SecSwitchStack) 34 ASM_PFX(SecSwitchStack): 35 # 36 # Save three register: eax, ebx, ecx 37 # 38 push %eax 39 push %ebx 40 push %ecx 41 push %edx 42 43 # 44 # !!CAUTION!! this function address's is pushed into stack after 45 # migration of whole temporary memory, so need save it to permenent 46 # memory at first! 47 # 48 49 movl 20(%esp), %ebx # Save the first parameter 50 movl 24(%esp), %ecx # Save the second parameter 51 52 # 53 # Save this function's return address into permenent memory at first. 54 # Then, Fixup the esp point to permenent memory 55 # 56 57 movl %esp, %eax 58 subl %ebx, %eax 59 addl %ecx, %eax 60 movl (%esp), %edx # copy pushed register's value to permenent memory 61 movl %edx, (%eax) 62 movl 4(%esp), %edx 63 movl %edx, 4(%eax) 64 movl 8(%esp), %edx 65 movl %edx, 8(%eax) 66 movl 12(%esp), %edx 67 movl %edx, 12(%eax) 68 movl 16(%esp), %edx 69 movl %edx, 16(%eax) 70 movl %eax, %esp # From now, esp is pointed to permenent memory 71 72 # 73 # Fixup the ebp point to permenent memory 74 # 75 #ifndef __APPLE__ 76 movl %ebp, %eax 77 subl %ebx, %eax 78 addl %ecx, %eax 79 movl %eax, %ebp # From now, ebp is pointed to permenent memory 80 81 # 82 # Fixup callee's ebp point for PeiDispatch 83 # 84 movl (%ebp), %eax 85 subl %ebx, %eax 86 addl %ecx, %eax 87 movl %eax, (%ebp) # From now, Temporary's PPI caller's stack is in permenent memory 88 #endif 89 90 pop %edx 91 pop %ecx 92 pop %ebx 93 pop %eax 94 ret 95 96
