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;------------------------------------------------------------------------------
;
; Copyright (c) 2013, Intel Corporation. All rights reserved.<BR>
; This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
; http://opensource.org/licenses/bsd-license.php
;
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;
; Module Name:
;
; Stack.asm
;
; Abstract:
;
; Switch the stack from temporary memory to permenent memory.
;
;------------------------------------------------------------------------------
.code
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; SecSwitchStack (
; UINT32 TemporaryMemoryBase,
; UINT32 PermenentMemoryBase
; );
;------------------------------------------------------------------------------
SecSwitchStack PROC
mov [rsp + 08h], rcx
mov [rsp + 10h], rdx
;
; Save three register: eax, ebx, ecx
;
push rax
push rbx
push rcx
push rdx
;
; !!CAUTION!! this function address's is pushed into stack after
; migration of whole temporary memory, so need save it to permenent
; memory at first!
;
mov rbx, [rsp + 28h] ; Save the first parameter
mov rcx, [rsp + 30h] ; Save the second parameter
;
; Save this function's return address into permenent memory at first.
; Then, Fixup the esp point to permenent memory
;
mov rax, rsp
sub rax, rbx
add rax, rcx
mov rdx, qword ptr [rsp] ; copy pushed register's value to permenent memory
mov qword ptr [rax], rdx
mov rdx, qword ptr [rsp + 8]
mov qword ptr [rax + 8], rdx
mov rdx, qword ptr [rsp + 10h]
mov qword ptr [rax + 10h], rdx
mov rdx, qword ptr [rsp + 18h]
mov qword ptr [rax + 18h], rdx
mov rdx, qword ptr [rsp + 20h] ; Update this function's return address into permenent memory
mov qword ptr [rax + 20h], rdx
mov rsp, rax ; From now, esp is pointed to permenent memory
;
; Fixup the ebp point to permenent memory
;
mov rax, rbp
sub rax, rbx
add rax, rcx
mov rbp, rax ; From now, ebp is pointed to permenent memory
pop rdx
pop rcx
pop rbx
pop rax
ret
SecSwitchStack ENDP
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; PeiSwitchStacks (
; IN SWITCH_STACK_ENTRY_POINT EntryPoint,
; IN VOID *Context1, OPTIONAL
; IN VOID *Context2, OPTIONAL
; IN VOID *Context3, OPTIONAL
; IN VOID *NewStack
; )
;------------------------------------------------------------------------------
PeiSwitchStacks PROC
mov rax, rcx
mov rcx, rdx
mov rdx, r8
mov r8, r9
mov rsp, [rsp + 28h]
sub rsp, 20h
call rax
jmp $
ret
PeiSwitchStacks ENDP
END
|
