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/*
* kexec: Linux boots Linux
*
* 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.
*/
.text
.code32
setup_legacy_pic:
/* Load the legacy dos settings into the 8259A pic */
movb $0xff, %al
outb %al, $0x21 /* mask all of 8259A-1 */
outb %al, $0xa1 /* mask all of 8259A-1 */
movb $0x11, %al
outb %al, $0x20 /* ICW1: select 8259A-1 init */
outb %al, $0x80 /* A short delay */
movb $0x08, %al
outb %al, $0x21 /* ICW2: 8259A-1 IR0-7 mappend to 0x8-0xf */
outb %al, $0x80 /* A short delay */
movb $01, %al
outb %al, $0x21 /* Normal 8086 auto EOI mode */
outb %al, $0x80 /* A short delay */
movb $0x11, %al
outb %al, $0xA0 /* ICW1: select 8259A-2 init */
outb %al, $0x80 /* A short delay */
movb $0x70, %al
outb %al, $0xA1 /* ICW2: 8259A-2 IR0-7 mappend to 0x70-0x77 */
outb %al, $0x80 /* A short delay */
movb $01, %al
outb %al, $0xA1 /* Normal 8086 auto EOI mode */
outb %al, $0x80 /* A short delay */
movb $0, %al
outb %al, $0x21 /* Unmask all of 8259A-1 */
outb %al, $0xa1 /* Unmask all of 8259A-2 */
ret
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