src/southbridge/intel/i82801gx/smbus.c

/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2008-2009 coresystems GmbH
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#include <console/console.h>
#include <device/device.h>
#include <device/path.h>
#include <device/smbus.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <device/pci_ops.h>
#include <arch/io.h>
#include "i82801gx.h"
#include "smbus.h"

#define SMB_BASE 0x20
static void smbus_init(struct device *dev)
{
	u32 smb_base;

	smb_base = pci_read_config32(dev, SMB_BASE);
	printk(BIOS_DEBUG, "Initializing SMBus device:\n");
	printk(BIOS_DEBUG, "  Old SMBUS Base Address: 0x%04x\n", smb_base);
	pci_write_config32(dev, SMB_BASE, 0x00000401);
	smb_base = pci_read_config32(dev, SMB_BASE);
	printk(BIOS_DEBUG, "  New SMBUS Base Address: 0x%04x\n", smb_base);
}

static int lsmbus_read_byte(device_t dev, u8 address)
{
	u16 device;
	struct resource *res;
	struct bus *pbus;

	device = dev->path.i2c.device;
	pbus = get_pbus_smbus(dev);
	res = find_resource(pbus->dev, 0x20);

	return do_smbus_read_byte(res->base, device, address);
}

static struct smbus_bus_operations lops_smbus_bus = {
	.read_byte	= lsmbus_read_byte,
};

static void smbus_set_subsystem(device_t dev, unsigned vendor, unsigned device)
{
	if (!vendor || !device) {
		pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID,
				pci_read_config32(dev, PCI_VENDOR_ID));
	} else {
		pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID,
				((device & 0xffff) << 16) | (vendor & 0xffff));
	}
}

static struct pci_operations smbus_pci_ops = {
	.set_subsystem    = smbus_set_subsystem,
};

static struct device_operations smbus_ops = {
	.read_resources		= pci_dev_read_resources,
	.set_resources		= pci_dev_set_resources,
	.enable_resources	= pci_dev_enable_resources,
	.init			= smbus_init,
	.scan_bus		= scan_static_bus,
	.enable			= i82801gx_enable,
	.ops_smbus_bus		= &lops_smbus_bus,
	.ops_pci		= &smbus_pci_ops,
};

/* 82801GB/GR/GDH/GBM/GHM/GU (ICH7/ICH7R/ICH7DH/ICH7-M/ICH7-M DH/ICH7-U) */
static const struct pci_driver i82801gx_smbus __pci_driver = {
	.ops	= &smbus_ops,
	.vendor	= PCI_VENDOR_ID_INTEL,
	.device	= 0x27da,
};