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#------------------------------------------------------------------------------
#
# Copyright (c) 2008, 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:
# ProcessorAsms.S
#
# Abstract:
# This is separated from processor.c to allow this functions to be built with /O1
#
#
#------------------------------------------------------------------------------
#include <EfiBind.h>
.text
.globl ASM_PFX(SwitchStacks)
.globl ASM_PFX(TransferControlSetJump)
.globl ASM_PFX(TransferControlLongJump)
#
# Routine Description:
# This allows the caller to switch the stack and goes to the new entry point
#
# Arguments:
# EntryPoint - Pointer to the location to enter // rcx
# Parameter - Parameter to pass in // rdx
# NewStack - New Location of the stack // r8
# NewBsp - New BSP // r9 - not used
#
# Returns:
# Nothing. Goes to the Entry Point passing in the new parameters
#
ASM_PFX(SwitchStacks):
# Adjust stack for
# 1) leave 4 registers space
# 2) let it 16 bytes aligned after call
sub $0x20,%r8
and -0x10,%r8w # do not assume 16 bytes aligned
mov %r8,%rsp
mov %rcx,%r10
mov %rdx,%rcx
callq *%r10
#
# no ret as we have a new stack and we jumped to the new location
#
ret
#SwitchStacks ENDP
.equ EFI_SUCCESS, 0
.equ EFI_WARN_RETURN_FROM_LONG_JUMP, 5
#
#Routine Description:
#
# This routine implements the x64 variant of the SetJump call. Its
# responsibility is to store system state information for a possible
# subsequent LongJump.
#
#Arguments:
#
# Pointer to CPU context save buffer.
#
#Returns:
#
# EFI_SUCCESS
#
# EFI_STATUS
# EFIAPI
# TransferControlLongJump (
# IN EFI_PEI_TRANSFER_CONTROL_PROTOCOL *This,
# IN EFI_JUMP_BUFFER *Jump
# );
#
# rcx - *This
# rdx - JumpBuffer
#
ASM_PFX(TransferControlSetJump):
mov %rbx,(%rdx)
mov %rsp,0x8(%rdx)
mov %rbp,0x10(%rdx)
mov %rdi,0x18(%rdx)
mov %rsi,0x20(%rdx)
mov %r10,0x28(%rdx)
mov %r11,0x30(%rdx)
mov %r12,0x38(%rdx)
mov %r13,0x40(%rdx)
mov %r14,0x48(%rdx)
mov %r15,0x50(%rdx)
mov (%rsp),%rax
mov %rax,0x58(%rdx)
mov $0x0,%rax
retq
#
# EFI_STATUS
# EFIAPI
# TransferControlLongJump (
# IN EFI_PEI_TRANSFER_CONTROL_PROTOCOL *This, // rcx
# IN EFI_JUMP_BUFFER *Jump // rdx
# );
#
#
ASM_PFX(TransferControlLongJump):
# set return from SetJump to EFI_WARN_RETURN_FROM_LONG_JUMP
mov $0x5,%rax
mov (%rdx),%rbx
mov 0x8(%rdx),%rsp
mov 0x10(%rdx),%rbp
mov 0x18(%rdx),%rdi
mov 0x20(%rdx),%rsi
mov 0x28(%rdx),%r10
mov 0x30(%rdx),%r11
mov 0x38(%rdx),%r12
mov 0x40(%rdx),%r13
mov 0x48(%rdx),%r14
mov 0x50(%rdx),%r15
add $0x8,%rsp
jmpq *0x58(%rdx)
mov $0x5,%rax
retq
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