1 ;------------------------------------------------------------------------------ 2 ; 3 ; Copyright (c) 2013, 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 .code 23 24 ;------------------------------------------------------------------------------ 25 ; VOID 26 ; EFIAPI 27 ; SecSwitchStack ( 28 ; UINT32 TemporaryMemoryBase, 29 ; UINT32 PermenentMemoryBase 30 ; ); 31 ;------------------------------------------------------------------------------ 32 SecSwitchStack PROC 33 mov [rsp + 08h], rcx 34 mov [rsp + 10h], rdx 35 36 ; 37 ; Save three register: eax, ebx, ecx 38 ; 39 push rax 40 push rbx 41 push rcx 42 push rdx 43 44 ; 45 ; !!CAUTION!! this function address's is pushed into stack after 46 ; migration of whole temporary memory, so need save it to permenent 47 ; memory at first! 48 ; 49 50 mov rbx, [rsp + 28h] ; Save the first parameter 51 mov rcx, [rsp + 30h] ; Save the second parameter 52 53 ; 54 ; Save this function's return address into permenent memory at first. 55 ; Then, Fixup the esp point to permenent memory 56 ; 57 mov rax, rsp 58 sub rax, rbx 59 add rax, rcx 60 mov rdx, qword ptr [rsp] ; copy pushed register's value to permenent memory 61 mov qword ptr [rax], rdx 62 mov rdx, qword ptr [rsp + 8] 63 mov qword ptr [rax + 8], rdx 64 mov rdx, qword ptr [rsp + 10h] 65 mov qword ptr [rax + 10h], rdx 66 mov rdx, qword ptr [rsp + 18h] 67 mov qword ptr [rax + 18h], rdx 68 mov rdx, qword ptr [rsp + 20h] ; Update this function's return address into permenent memory 69 mov qword ptr [rax + 20h], rdx 70 mov rsp, rax ; From now, esp is pointed to permenent memory 71 72 ; 73 ; Fixup the ebp point to permenent memory 74 ; 75 mov rax, rbp 76 sub rax, rbx 77 add rax, rcx 78 mov rbp, rax ; From now, ebp is pointed to permenent memory 79 80 pop rdx 81 pop rcx 82 pop rbx 83 pop rax 84 ret 85 SecSwitchStack ENDP 86 87 ;------------------------------------------------------------------------------ 88 ; VOID 89 ; EFIAPI 90 ; PeiSwitchStacks ( 91 ; IN SWITCH_STACK_ENTRY_POINT EntryPoint, 92 ; IN VOID *Context1, OPTIONAL 93 ; IN VOID *Context2, OPTIONAL 94 ; IN VOID *Context3, OPTIONAL 95 ; IN VOID *NewStack 96 ; ) 97 ;------------------------------------------------------------------------------ 98 PeiSwitchStacks PROC 99 mov rax, rcx 100 mov rcx, rdx 101 mov rdx, r8 102 mov r8, r9 103 mov rsp, [rsp + 28h] 104 sub rsp, 20h 105 call rax 106 jmp $ 107 ret 108 PeiSwitchStacks ENDP 109 110 END 111
