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/*
* purgatory: setup code
*
* Copyright (C) 2003,2004 Eric Biederman (ebiederm@xmission.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation (version 2 of the License).
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#undef i386
.text
.arch i386
.globl purgatory_start
purgatory_start:
.code32
/* Load a gdt so I know what the segment registers are */
lgdt %cs:gdt
/* load the data segments */
movl $0x08, %eax /* data segment */
movl %eax, %ds
movl %eax, %es
movl %eax, %ss
movl %eax, %fs
movl %eax, %gs
/* load the code segment */
ljmp $0x10,$1f
1:
movl 0(%esp), %eax
movl %eax, jump_back_entry
/* Setup a stack */
movl $lstack_end, %esp
/* Call the C code */
call purgatory
jmp entry32
.section ".rodata"
.balign 16
gdt:
/* 0x00 unusable segment so used as the gdt ptr */
.word gdt_end - gdt - 1
.long gdt
.word 0
/* 0x8 4GB flat data segment */
.word 0xFFFF, 0x0000, 0x9200, 0x00CF
/* 0x10 4GB flat code segment */
.word 0xFFFF, 0x0000, 0x9A00, 0x00CF
gdt_end:
/* A stack for the purgatory code */
.bss
.balign 4096
lstack:
.skip 4096
lstack_end:
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