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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 entry32, entry32_regs
entry32:
	.code32

	/* Setup a gdt that should that is generally usefully */
	lgdt	%cs:gdt

	/* load the data segments */
	movl	$0x18, %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:		

	/* Load the registers */
	movl	eax, %eax
	movl	ecx, %ecx
	movl	edx, %edx
	movl	esi, %esi
	movl	edi, %edi
	movl	esp, %esp
	movl	ebp, %ebp
	movl	ebx, %ebx

	/* Jump to the loaded image */
	jmpl	*(eip)

	.section ".rodata"
	.balign 16
gdt:
	/* 0x00 unusable segment so used as the gdt ptr */
	.word	gdt_end - gdt - 1
	.long	gdt
	.word	0

	/* 0x08 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000

	/* Documented linux kernel segments */
	/* 0x10 4GB flat code segment */
	.word	0xFFFF, 0x0000, 0x9A00, 0x00CF
	/* 0x18 4GB flat data segment */
	.word	0xFFFF, 0x0000, 0x9200, 0x00CF

	/* 0x20 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x28 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x30 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x38 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x40 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x48 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x50 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	/* 0x58 dummy */
	.word	0x0000, 0x0000, 0x0000, 0x000
	
	/* Segments used by the 2.5.x kernel */
	/* 0x60 4GB flat code segment */
	.word	0xFFFF, 0x0000, 0x9A00, 0x00CF
	/* 0x68 4GB flat data segment */
	.word	0xFFFF, 0x0000, 0x9200, 0x00CF
gdt_end:
	
	.data 
	.balign 4
entry32_regs:  
eax:	.long 0x00000000
ebx:	.long 0x00000000
ecx:	.long 0x00000000
edx:	.long 0x00000000
esi:	.long 0x00000000
edi:	.long 0x00000000
esp:	.long 0x00000000
ebp:	.long 0x00000000
eip:	.long entry16
	.size entry32_regs, . - entry32_regs