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#------------------------------------------------------------------------------
#
# Copyright (c) 2006, Intel Corporation
# All rights reserved. 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:
#
# Thunk.asm
#
# Abstract:
#
# Real mode thunk
#
#------------------------------------------------------------------------------
MISMATCH: "EXTERNDEF C mCode16Size:DWORD"
MISMATCH: "CONST SEGMENT FLAT "DATA" READONLY"
MISMATCH: "mCode16Size DD _TEXT16SIZE"
MISMATCH: "CONSTS"
MISMATCH: "_DATA SEGMENT FLAT "DATA""
MISMATCH: "NullSegSel DQ 0"
MISMATCH: "_16BitCsSel LABEL QWORD"
.word -1
.word 0
.byte 0
.byte 0x9b
.byte 0x8f # 16-bit segment
.byte 0
MISMATCH: "_16Gdtr LABEL FWORD"
MISMATCH: " DW $ - offset NullSegSel - 1"
MISMATCH: " DD offset NullSegSel"
MISMATCH: "_DATAS"
MISMATCH: "_TEXT SEGMENT FLAT "CODE" PARA"
MISMATCH: "IA32_REGS STRUC 4t"
MISMATCH: "_EDI DD ?"
MISMATCH: "_ESI DD ?"
MISMATCH: "_EBP DD ?"
MISMATCH: "_ESP DD ?"
MISMATCH: "_EBX DD ?"
MISMATCH: "_EDX DD ?"
MISMATCH: "_ECX DD ?"
MISMATCH: "_EAX DD ?"
MISMATCH: "_DS DW ?"
MISMATCH: "_ES DW ?"
MISMATCH: "_FS DW ?"
MISMATCH: "_GS DW ?"
MISMATCH: "_EFLAGS DD ?"
MISMATCH: "_EIP DD ?"
MISMATCH: "_CS DW ?"
MISMATCH: "_SS DW ?"
MISMATCH: "IA32_REGSS"
MISMATCH: "_STK16 STRUC 1t"
MISMATCH: "RetEip DD ?"
MISMATCH: "RetCs DW ?"
MISMATCH: "ThunkFlags DW ?"
MISMATCH: "SavedEsp DD ?"
MISMATCH: "SavedSs DW ?"
MISMATCH: "SavedGdtr FWORD ?"
MISMATCH: "SavedCr0 DD ?"
MISMATCH: "SavedCr4 DD ?"
MISMATCH: "_STK16S"
.global _InternalAsmThunk16
MISMATCH: "_InternalAsmThunk16: USES ebp ebx esi edi ds es fs gs"
MISMATCH: " ASSUME esi:PTR IA32_REGS"
movl 36(%esp),%esi
MISMATCH: " movzx edx, [esi]._SS"
movl $[esi]._ESP, %edi
MISMATCH: " add edi, - sizeof (_STK16) - sizeof (IA32_REGS)"
pushl %edi # save stack offset
imull $16,%edx,%eax # eax <- edx*16
addl %eax,%edi # edi <- linear address of 16-bit stack
MISMATCH: " push sizeof (IA32_REGS) / 4"
popl %ecx
rep
movsl # copy context to 16-bit stack
popl %ebx # ebx <- 16-bit stack offset
MISMATCH: " mov eax, offset @F "
stosl
movl %cs,%eax # return segment
stosw
movl 40(%esp),%eax # THUNK flags
stosw
movl %esp,%eax
stosl # save esp
movl %ss,%eax # save ss
stosw
MISMATCH: " sgdt fword ptr [edi] "
MISMATCH: " sidt fword ptr [esp + 36] "
movl %cr0, %esi
movl %esi,6(%edi) # save CR0
MISMATCH: " and esi, NOT 80000001h "
movl %cr4, %eax
movl %eax,10(%edi) # save CR4
MISMATCH: " and al, NOT 30h "
movl %edx,%edi # edi <- 16-bit stack segment
movl 44(%esp),%edx
shll $16,%edx
pushl %edx
MISMATCH: " lgdt _16Gdtr "
.byte 0xea
MISMATCH: " DD offset @16Bit"
.word 8 # jmp far 8:@16Bit
@16Bit:
movl %esi, %cr0 # disable protected mode
movl %eax, %cr4 # disable PAE & PSE
lret
@@:
movl %ss,%eax
shll $4,%eax
addl %esp,%eax # eax <- address of 16-bit stack
MISMATCH: " lss esp, fword ptr (_STK16 ptr [esp + sizeof (IA32_REGS)]).SavedEsp"
MISMATCH: " lidt fword ptr [esp + 36] "
ret
MISMATCH: "_TEXTS"
MISMATCH: "_TEXT16 SEGMENT USE16 "CODE" PARA"
.global _Code16Addr
MISMATCH: "_Code16Addr: C"
.global RealMode
RealMode:
MISMATCH: " ASSUME bp:PTR _STK16"
movw %di,%ss # set up stack
movl %ebx,%esp
MISMATCH: " lidt fword ptr cs:[_16Idtr - _Code16Addr]"
popal
popl %ds
popl %es
popl %fs
popl %gs
addw $4,%sp # skip EFlags
MISMATCH: " test (_STK16 ptr [esp + 8]).ThunkFlags, 1"
jz @F
pushf
@@:
pushw %cs
MISMATCH: " push @FarCallRet - _Code16Addr"
jz @F
MISMATCH: " jmp fword ptr [esp + 6]"
@@:
MISMATCH: " jmp fword ptr [esp + 4]"
@FarCallRet:
pushfl
pushw %gs
pushw %fs
pushw %es
pushw %ds
pushal
cli
MISMATCH: " lea bp, [esp + sizeof (IA32_REGS)]"
.byte 0x66
MISMATCH: " lgdt [bp].SavedGdtr"
movl $[bp].SavedCr4, %eax
movl %eax, %cr4
movl $[bp].SavedCr0, %eax
movl %eax, %cr0 # restore CR0
MISMATCH: " jmp fword ptr [bp].RetEip"
MISMATCH: "_16Idtr FWORD (1 SHL 10) - 1"
_TEXT16:
MISMATCH: "_TEXT16SIZE = _TEXT16- _Code16Addr"
MISMATCH: "_TEXT16S"
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