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| #------------------------------------------------------------------------------
| #
| # Copyright (c) 2007, Intel Corporation. All rights reserved.<BR>
| # SPDX-License-Identifier: BSD-2-Clause-Patent
| #
| # Module Name:
| #
| # Stack.asm
| #
| # Abstract:
| #
| # Switch the stack from temporary memory to permanent memory.
| #
| #------------------------------------------------------------------------------
|
| .text
|
|
| //------------------------------------------------------------------------------
| // VOID
| // EFIAPI
| // SecSwitchStack (
| // UINT32 TemporaryMemoryBase,
| // UINT32 PermenentMemoryBase
| // )//
| //------------------------------------------------------------------------------
| ASM_GLOBAL ASM_PFX(SecSwitchStack)
| ASM_PFX(SecSwitchStack):
| #
| # 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 permanent
| # 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 permanent memory at first.
| # Then, Fixup the esp point to permanent memory
| #
|
| movl %esp, %eax
| subl %ebx, %eax
| addl %ecx, %eax
| movl (%esp), %edx # copy pushed register's value to permanent memory
| movl %edx, (%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
| movl %edx, 16(%eax)
| movl %eax, %esp # From now, esp is pointed to permanent memory
|
| #
| # Fixup the ebp point to permanent memory
| #
| #ifndef __APPLE__
| movl %ebp, %eax
| subl %ebx, %eax
| addl %ecx, %eax
| movl %eax, %ebp # From now, ebp is pointed to permanent memory
|
| #
| # Fixup callee's ebp point for PeiDispatch
| #
| movl (%ebp), %eax
| subl %ebx, %eax
| addl %ecx, %eax
| movl %eax, (%ebp) # From now, Temporary's PPI caller's stack is in permanent memory
| #endif
|
| pop %edx
| pop %ecx
| pop %ebx
| pop %eax
| ret
|
|
|
