src/superio/winbond/w83977tf/early_serial.c

/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2000 AG Electronics Ltd.
 * Copyright (C) 2003-2004 Linux Networx
 * Copyright (C) 2004 Tyan
 *
 * 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 */

#include <arch/io.h>
#include "w83977tf.h"

static void pnp_enter_ext_func_mode(pnp_devfn_t dev)
{
	u16 port = dev >> 8;
	outb(0x87, port);
	outb(0x87, port);
}

static void pnp_exit_ext_func_mode(pnp_devfn_t dev)
{
	u16 port = dev >> 8;
	outb(0xaa, port);
}

static void w83977tf_enable_serial(pnp_devfn_t dev, u16 iobase)
{
	pnp_enter_ext_func_mode(dev);
	pnp_set_logical_device(dev);
	pnp_set_enable(dev, 0);
	pnp_set_iobase(dev, PNP_IDX_IO0, iobase);
	pnp_set_enable(dev, 1);
	pnp_exit_ext_func_mode(dev);
}