src/soc/intel/skylake/smbus.c

/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2008-2009 coresystems GmbH
 * Copyright (C) 2014 Google Inc.
 * Copyright (C) 2015 Intel 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; 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.
 */

#include <arch/io.h>
#include <console/console.h>
#include <device/device.h>
#include <device/path.h>
#include <device/smbus.h>
#include <device/smbus_def.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <device/pci_ops.h>
#include <soc/iomap.h>
#include <soc/ramstage.h>
#include <soc/smbus.h>

static void pch_smbus_init(device_t dev)
{
	struct resource *res;
	u16 reg16;

	/* Enable clock gating */
	reg16 = pci_read_config32(dev, 0x80);
	reg16 &= ~((1 << 8)|(1 << 10)|(1 << 12)|(1 << 14));
	pci_write_config32(dev, 0x80, reg16);

	/* Set Receive Slave Address */
	res = find_resource(dev, PCI_BASE_ADDRESS_4);
	if (res)
		outb(SMBUS_SLAVE_ADDR, res->base + SMB_RCV_SLVA);
}

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, PCI_BASE_ADDRESS_4);

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

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

	device = dev->path.i2c.device;
	pbus = get_pbus_smbus(dev);
	res = find_resource(pbus->dev, PCI_BASE_ADDRESS_4);
	return do_smbus_write_byte(res->base, device, address, data);
}

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

static void smbus_read_resources(device_t dev)
{
	struct resource *res = new_resource(dev, PCI_BASE_ADDRESS_4);
	res->base = SMBUS_BASE_ADDRESS;
	res->size = 32;
	res->limit = res->base + res->size - 1;
	res->flags = IORESOURCE_IO | IORESOURCE_FIXED | IORESOURCE_RESERVE |
		     IORESOURCE_STORED | IORESOURCE_ASSIGNED;

	/* Also add MMIO resource */
	res = pci_get_resource(dev, PCI_BASE_ADDRESS_0);
}

static struct device_operations smbus_ops = {
	.read_resources		= &smbus_read_resources,
	.set_resources		= &pci_dev_set_resources,
	.enable_resources	= &pci_dev_enable_resources,
	.scan_bus		= &scan_smbus,
	.init			= &pch_smbus_init,
	.ops_smbus_bus		= &lops_smbus_bus,
	.ops_pci		= &soc_pci_ops,
};

static const unsigned short pci_device_ids[] = {
	0x9d23, /* SunRisePoint LP */
	0
};

static const struct pci_driver pch_smbus __pci_driver = {
	.ops	 = &smbus_ops,
	.vendor	 = PCI_VENDOR_ID_INTEL,
	.devices = pci_device_ids,
};