mirror of https://github.com/acidanthera/audk.git
79 lines
2.4 KiB
ArmAsm
79 lines
2.4 KiB
ArmAsm
#------------------------------------------------------------------------------
|
|
#
|
|
# 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.
|
|
#
|
|
# Abstract:
|
|
#
|
|
# Switch the stack from temporary memory to permenent memory.
|
|
#
|
|
#------------------------------------------------------------------------------
|
|
|
|
|
|
#------------------------------------------------------------------------------
|
|
# VOID
|
|
# EFIAPI
|
|
# SecSwitchStack (
|
|
# UINT32 TemporaryMemoryBase,
|
|
# UINT32 PermenentMemoryBase
|
|
# )#
|
|
#------------------------------------------------------------------------------
|
|
ASM_GLOBAL ASM_PFX (SecSwitchStack)
|
|
ASM_PFX(SecSwitchStack):
|
|
#
|
|
# Save standard registers so they can be used to change stack
|
|
#
|
|
pushl %eax
|
|
pushl %ebx
|
|
pushl %ecx
|
|
pushl %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!
|
|
#
|
|
movl 20(%esp), %ebx # Save the first parameter
|
|
movl 24(%esp), %ecx # Save the second parameter
|
|
|
|
#
|
|
# Save this function's return address into permenent memory at first.
|
|
# Then, Fixup the esp point to permenent memory
|
|
#
|
|
movl %esp, %eax
|
|
subl %ebx, %eax
|
|
addl %ecx, %eax
|
|
movl 0(%esp), %edx # copy pushed register's value to permenent memory
|
|
movl %edx, 0(%eax)
|
|
movl 4(%esp), %edx
|
|
movl %edx, 4(%eax)
|
|
movl 8(%esp), %edx
|
|
movl %edx, 8(%eax)
|
|
movl 12(%esp), %edx
|
|
movl %edx, 12(%eax)
|
|
movl 16(%esp), %edx # Update this function's return address into permenent memory
|
|
movl %edx, 16(%eax)
|
|
movl %eax, %esp # From now, esp is pointed to permenent memory
|
|
|
|
#
|
|
# Fixup the ebp point to permenent memory
|
|
#
|
|
movl %ebp, %eax
|
|
subl %ebx, %eax
|
|
addl %ecx, %eax
|
|
movl %eax, %ebp # From now, ebp is pointed to permenent memory
|
|
|
|
popl %edx
|
|
popl %ecx
|
|
popl %ebx
|
|
popl %eax
|
|
ret
|
|
|
|
|