Contributed-under: TianoCore Contribution Agreement 1.0 Signed off by: Jiewen Yao <jiewen.yao@intel.com> Reviewed by: Ravi Rangarajan <ravi.p.rangarajan@intel.com> Reviewed by: Maurice Ma <maurice.ma@intel.com> Reviewed by: Giri Mudusuru <giri.p.mudusuru@intel.com> Reviewed by: Liming Gao <liming.gao@intel.com> git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15676 6f19259b-4bc3-4df7-8a09-765794883524
		
			
				
	
	
		
			83 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			NASM
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			NASM
		
	
	
	
	
	
| ;------------------------------------------------------------------------------
 | |
| ;
 | |
| ; Copyright (c) 2014, 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.
 | |
| ;
 | |
| ; Abstract:
 | |
| ;
 | |
| ;   Switch the stack from temporary memory to permenent memory.
 | |
| ;
 | |
| ;------------------------------------------------------------------------------
 | |
| 
 | |
|     .586p
 | |
|     .model  flat,C
 | |
|     .code
 | |
| 
 | |
| ;------------------------------------------------------------------------------
 | |
| ; VOID
 | |
| ; EFIAPI
 | |
| ; SecSwitchStack (
 | |
| ;   UINT32   TemporaryMemoryBase,
 | |
| ;   UINT32   PermenentMemoryBase
 | |
| ;   );
 | |
| ;------------------------------------------------------------------------------
 | |
| SecSwitchStack   PROC
 | |
|     ;
 | |
|     ; Save three register: eax, ebx, ecx
 | |
|     ;
 | |
|     push  eax
 | |
|     push  ebx
 | |
|     push  ecx
 | |
|     push  edx
 | |
| 
 | |
|     ;
 | |
|     ; !!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   ebx, [esp + 20]          ; Save the first parameter
 | |
|     mov   ecx, [esp + 24]          ; Save the second parameter
 | |
| 
 | |
|     ;
 | |
|     ; Save this function's return address into permenent memory at first.
 | |
|     ; Then, Fixup the esp point to permenent memory
 | |
|     ;
 | |
|     mov   eax, esp
 | |
|     sub   eax, ebx
 | |
|     add   eax, ecx
 | |
|     mov   edx, dword ptr [esp]         ; copy pushed register's value to permenent memory
 | |
|     mov   dword ptr [eax], edx
 | |
|     mov   edx, dword ptr [esp + 4]
 | |
|     mov   dword ptr [eax + 4], edx
 | |
|     mov   edx, dword ptr [esp + 8]
 | |
|     mov   dword ptr [eax + 8], edx
 | |
|     mov   edx, dword ptr [esp + 12]
 | |
|     mov   dword ptr [eax + 12], edx
 | |
|     mov   edx, dword ptr [esp + 16]    ; Update this function's return address into permenent memory
 | |
|     mov   dword ptr [eax + 16], edx
 | |
|     mov   esp, eax                     ; From now, esp is pointed to permenent memory
 | |
| 
 | |
|     ;
 | |
|     ; Fixup the ebp point to permenent memory
 | |
|     ;
 | |
|     mov   eax, ebp
 | |
|     sub   eax, ebx
 | |
|     add   eax, ecx
 | |
|     mov   ebp, eax                ; From now, ebp is pointed to permenent memory
 | |
| 
 | |
|     pop   edx
 | |
|     pop   ecx
 | |
|     pop   ebx
 | |
|     pop   eax
 | |
|     ret
 | |
| SecSwitchStack   ENDP
 | |
| 
 | |
|     END
 |