i82801ix: Provide ramstage smbus functions.

Change-Id: Idc62e382a4002274abe6c23d76fe0874c62846c5
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/6433
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>

src/southbridge/intel/i82801ix/Makefile.inc

@@ -26,6 +26,7 @@ ramstage-y += usb_ehci.c
 ramstage-y += sata.c
 ramstage-y += hdaudio.c
 ramstage-y += thermal.c
+ramstage-y += smbus.c
 
 ramstage-y += ../i82801gx/reset.c
 ramstage-y += ../i82801gx/watchdog.c

src/southbridge/intel/i82801ix/smbus.c

@@ -0,0 +1,116 @@
+/*
+ * 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 "smbus.h"
+
+static void pch_smbus_init(device_t dev)
+{
+	u16 reg16;
+
+	/* Enable clock gating */
+	reg16 = pci_read_config16(dev, 0x80);
+	reg16 &= ~((1 << 8)|(1 << 10)|(1 << 12)|(1 << 14));
+	pci_write_config16(dev, 0x80, reg16);
+}
+
+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 int lsmbus_write_byte(device_t dev, u8 address, u8 val)
+{
+	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_write_byte(res->base, device, address, val);
+}
+
+static struct smbus_bus_operations lops_smbus_bus = {
+	.read_byte	= lsmbus_read_byte,
+	.write_byte	= lsmbus_write_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 void smbus_read_resources(device_t dev)
+{
+	struct resource *res = new_resource(dev, PCI_BASE_ADDRESS_4);
+	res->base = SMBUS_IO_BASE;
+	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_static_bus,
+	.init			= pch_smbus_init,
+	.ops_smbus_bus		= &lops_smbus_bus,
+	.ops_pci		= &smbus_pci_ops,
+};
+
+static const unsigned short pci_device_ids[] = { 0x2930, 0 };
+
+static const struct pci_driver pch_smbus __pci_driver = {
+	.ops	 = &smbus_ops,
+	.vendor	 = PCI_VENDOR_ID_INTEL,
+	.devices = pci_device_ids,
+};

src/southbridge/intel/i82801ix/smbus.h

@@ -97,3 +97,48 @@ static int do_smbus_read_byte(unsigned smbus_base, unsigned device, unsigned add
 	}
 	return byte;
 }
+
+#ifndef __PRE_RAM__
+static  int do_smbus_write_byte(unsigned smbus_base, unsigned device, unsigned address, unsigned data)
+{
+	unsigned char global_status_register;
+
+	if (smbus_wait_until_ready(smbus_base) < 0)
+		return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+
+	/* Setup transaction */
+	/* Disable interrupts */
+	outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL);
+	/* Set the device I'm talking too */
+	outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD);
+	/* Set the command/address... */
+	outb(address & 0xff, smbus_base + SMBHSTCMD);
+	/* Set up for a byte data read */
+	outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x2 << 2),
+	     (smbus_base + SMBHSTCTL));
+	/* Clear any lingering errors, so the transaction will run */
+	outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
+
+	/* Clear the data byte... */
+	outb(data, smbus_base + SMBHSTDAT0);
+
+	/* Start the command */
+	outb((inb(smbus_base + SMBHSTCTL) | 0x40),
+	     smbus_base + SMBHSTCTL);
+
+	/* Poll for transaction completion */
+	if (smbus_wait_until_done(smbus_base) < 0)
+		return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
+
+	global_status_register = inb(smbus_base + SMBHSTSTAT);
+
+	/* Ignore the "In Use" status... */
+	global_status_register &= ~(3 << 5);
+
+	/* Read results of transaction */
+	if (global_status_register != (1 << 1))
+		return SMBUS_ERROR;
+
+	return 0;
+}
+#endif