src/superio/smsc/lpc47n217/lpc47n217_early_serial.c

/*
 * $Header: /home/cvs/BIR/ca-cpu/freebios/src/superio/smsc/lpc47n217/lpc47n217_early_serial.c,v 1.1.1.1 2005/07/11 15:28:51 smagnani Exp $
 *
 * lpc47n217_early_serial.c: Pre-RAM driver for SMSC LPC47N217 Super I/O chip
 *
 * Copyright (C) 2005 Digital Design Corporation
 *
 * 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.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * $Log: lpc47n217_early_serial.c,v $
 * Revision 1.1.1.1  2005/07/11 15:28:51  smagnani
 * Initial revision.
 *
 *
 */

#include <arch/romcc_io.h>
#include <assert.h>
#include "lpc47n217.h"

//----------------------------------------------------------------------------------
// Function:    	pnp_enter_conf_state
// Parameters:  	dev - high 8 bits = Super I/O port
// Return Value:	None
// Description: 	Enable access to the LPC47N217's configuration registers.
//
static inline void pnp_enter_conf_state(device_t dev) {
	unsigned port = dev>>8;
    outb(0x55, port);
}

//----------------------------------------------------------------------------------
// Function:    	pnp_exit_conf_state
// Parameters:  	dev - high 8 bits = Super I/O port
// Return Value:	None
// Description: 	Disable access to the LPC47N217's configuration registers.
//
static void pnp_exit_conf_state(device_t dev) {
	unsigned port = dev>>8;
    outb(0xaa, port);
}

//----------------------------------------------------------------------------------
// Function:    	lpc47n217_pnp_set_iobase
// Parameters:  	dev - high 8 bits = Super I/O port, 
//						  low 8 bits = logical device number (per lpc47n217.h)
//					iobase - base I/O port for the logical device
// Return Value:	None
// Description: 	Program the base I/O port for the specified logical device.
//
void lpc47n217_pnp_set_iobase(device_t dev, unsigned iobase)
{
	// LPC47N217 requires base ports to be a multiple of 4
	ASSERT(!(iobase & 0x3));

	switch(dev & 0xFF) {
	case LPC47N217_PP: 
		pnp_write_config(dev, 0x23, (iobase >> 2) & 0xff);
		break;
		
	case LPC47N217_SP1: 
		pnp_write_config(dev, 0x24, (iobase >> 2) & 0xff);
		break;
		
	case LPC47N217_SP2:
		pnp_write_config(dev, 0x25, (iobase >> 2) & 0xff);
		break;
		
	default:
		break;
	}
}

//----------------------------------------------------------------------------------
// Function:    	lpc47n217_pnp_set_enable
// Parameters:  	dev - high 8 bits = Super I/O port, 
//						  low 8 bits = logical device number (per lpc47n217.h)
//					enable - 0 to disable, anythig else to enable
// Return Value:	None
// Description: 	Enable or disable the specified logical device.
//					Technically, a full disable requires setting the device's base
//					I/O port below 0x100. We don't do that here, because we don't
//					have access to a data structure that specifies what the 'real'
//					base port is (when asked to enable the device). Also the function
//					is used only to disable the device while its true base port is
//					programmed (see lpc47n217_enable_serial() below).
//
void lpc47n217_pnp_set_enable(device_t dev, int enable)
{
	uint8_t power_register = 0;
	uint8_t power_mask = 0;
	uint8_t current_power;
	uint8_t new_power;
	
	switch(dev & 0xFF) {
	case LPC47N217_PP: 
		power_register = 0x01;
		power_mask = 0x04;
		break;
		
	case LPC47N217_SP1: 
		power_register = 0x02;
		power_mask = 0x08;
		break;
		
	case LPC47N217_SP2:
		power_register = 0x02;
		power_mask = 0x80;
		break;
		
	default:
		return;
	}

	current_power = pnp_read_config(dev, power_register);
	new_power = current_power & ~power_mask;		// disable by default

	if (enable)
		new_power |= power_mask;		// Enable

	pnp_write_config(dev, power_register, new_power);
}

//----------------------------------------------------------------------------------
// Function:    	lpc47n217_enable_serial
// Parameters:  	dev - high 8 bits = Super I/O port, 
//						  low 8 bits = logical device number (per lpc47n217.h)
//					iobase - processor I/O port address to assign to this serial device
// Return Value:	bool
// Description: 	Configure the base I/O port of the specified serial device
//					and enable the serial device.
//
static void lpc47n217_enable_serial(device_t dev, unsigned iobase)
{
	// NOTE: Cannot use pnp_set_XXX() here because they assume chip
	//		 support for logical devices, which the LPC47N217 doesn't have
	
	pnp_enter_conf_state(dev);
	lpc47n217_pnp_set_enable(dev, 0);
	lpc47n217_pnp_set_iobase(dev, iobase);
	lpc47n217_pnp_set_enable(dev, 1);
	pnp_exit_conf_state(dev);
}