/*
 * This file is part of the coreboot project.
 *
 * It is based on the arch/i386/boot/setup.S file from the Linux kernel.
 */

/*
!       setup.S         Copyright (C) 1991, 1992 Linus Torvalds
!
! some changes and additional features by Christoph Niemann,
! March 1993/June 1994 (Christoph.Niemann@linux.org)
*/

#include <io.h>

/*
! well, that went ok, I hope. Now we have to reprogram the interrupts :-(
! we put them right after the intel-reserved hardware interrupts, at
! int 0x20-0x2F. There they won't mess up anything. Sadly IBM really
! messed this up with the original PC, and they haven't been able to
! rectify it afterwards. Thus the bios puts interrupts at 0x08-0x0f,
! which is used for the internal hardware interrupts as well. We just
! have to reprogram the 8259's, and it isn't fun.
 */
void setup_i8259(void)
{
	outb(0x11, 0x20);	/* Initialization sequence (8259A-1). */
	outb(0x11, 0xA0);	/* Initialization sequence (8259A-2). */
	outb(0x20, 0x21);	/* Start of hardware INTs (0x20). */
	outb(0x28, 0xA1);	/* Start of hardware INTs 2 (0x28). */
	outb(0x04, 0x21);	/* 8259-1 is master. */
	outb(0x02, 0xA1);	/* 8259-2 is slave. */
	outb(0x01, 0x21);	/* 8086 mode for both. */
	outb(0x01, 0xA1);
	outb(0xFF, 0xA1);	/* Mask off all interrupts for now. */
	outb(0xFB, 0x21);	/* Mask all IRQs but IRQ2 which is cascaded. */
}