Thanks to the great efforts of Morgan Tsai of SiS we support the SiS966
southbridge now:

From: Morgan Tsai <my_tsai@sis.com>                                                                                                       

It supports SiS761GX / SiS966 chipset, only for AMD K8 platform so far.
Due to integrated VGA sharing system memory, some code in southbridge
folder have to init northbridge.

Copyright (C) 2007 Morgan Tsai <my_tsai@sis.com>
Copyright (C) 2007 Silicon Integrated Systems Corp. (SiS)

Change Log:

Newly support GIGABYTE GA-2761GXDK
CPU type: AMD AM2 socket
Northbridge: SiS 761GX
Southbridge: SiS 966
SuperIO: ITE8716F

Signed-off-by: Morgan Tsai <my_tsai@sis.com>
Acked-by: Stefan Reinauer <stepan@coresystems.de>



git-svn-id: svn://svn.coreboot.org/coreboot/trunk@2902 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/southbridge/sis/sis966/sis966_smbus.h b/src/southbridge/sis/sis966/sis966_smbus.h
new file mode 100644
index 0000000..cc0e1db
--- /dev/null
+++ b/src/southbridge/sis/sis966/sis966_smbus.h
@@ -0,0 +1,202 @@
+/*
+ * This file is part of the LinuxBIOS project.
+ *
+ * Copyright (C) 2004 Tyan Computer
+ * Written by Yinghai Lu <yhlu@tyan.com> for Tyan Computer.
+ * Copyright (C) 2006,2007 AMD
+ * Written by Yinghai Lu <yinghai.lu@amd.com> for AMD.
+ * Copyright (C) 2007 Silicon Integrated Systems Corp. (SiS)
+ * Written by Morgan Tsai <my_tsai@sis.com> for SiS.
+ *
+ * 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
+ */
+
+#include <device/smbus_def.h>
+
+#define SMBHSTSTAT	0x1
+#define SMBHSTPRTCL	0x0
+#define SMBHSTCMD	0x3
+#define SMBXMITADD	0x2
+#define SMBHSTDAT0	0x4
+#define SMBHSTDAT1	0x5
+
+/* Between 1-10 seconds, We should never timeout normally
+ * Longer than this is just painful when a timeout condition occurs.
+ */
+#define SMBUS_TIMEOUT	(100*1000*10)
+
+static inline void smbus_delay(void)
+{
+	outb(0x80, 0x80);
+}
+
+static int smbus_wait_until_ready(unsigned smbus_io_base)
+{
+	unsigned long loops;
+	loops = SMBUS_TIMEOUT;
+	do {
+		unsigned char val;
+		smbus_delay();
+		val = inb(smbus_io_base + SMBHSTSTAT);
+		val &= 0x1f;
+		if (val == 0) {
+			return 0;
+		}
+		outb(val,smbus_io_base + SMBHSTSTAT);
+	} while(--loops);
+	return -2;
+}
+
+static int smbus_wait_until_done(unsigned smbus_io_base)
+{
+	unsigned long loops;
+	loops = SMBUS_TIMEOUT;
+	do {
+		unsigned char val;
+		smbus_delay();
+
+		val = inb(smbus_io_base + 0x00);
+		if ( (val & 0xff) != 0x02) {
+			return 0;
+		}
+	} while(--loops);
+	return -3;
+}
+static int do_smbus_recv_byte(unsigned smbus_io_base, unsigned device)
+{
+	unsigned char global_status_register;
+	unsigned char byte;
+
+	/* set the device I'm talking too */
+	outb(((device & 0x7f) << 1)|1 , smbus_io_base + SMBXMITADD);
+	smbus_delay();
+
+	/* byte data recv */
+	outb(0x05, smbus_io_base + SMBHSTPRTCL);
+	smbus_delay();
+
+	/* poll for transaction completion */
+	if (smbus_wait_until_done(smbus_io_base) < 0) {
+		return -3;
+	}
+
+	global_status_register = inb(smbus_io_base + SMBHSTSTAT) & 0x80; /* lose check */
+
+	/* read results of transaction */
+	byte = inb(smbus_io_base + SMBHSTCMD);
+
+	if (global_status_register != 0x80) { // lose check, otherwise it should be 0
+		return -1;
+	}
+	return byte;
+}
+static int do_smbus_send_byte(unsigned smbus_io_base, unsigned device, unsigned char val)
+{
+	unsigned global_status_register;
+
+	outb(val, smbus_io_base + SMBHSTDAT0);
+	smbus_delay();
+
+	/* set the command... */
+	outb(val, smbus_io_base + SMBHSTCMD);
+	smbus_delay();
+
+	/* set the device I'm talking too */
+	outb(((device & 0x7f) << 1) | 0, smbus_io_base + SMBXMITADD);
+	smbus_delay();
+
+	/* set up for a byte data write */
+	outb(0x04, smbus_io_base + SMBHSTPRTCL);
+	smbus_delay();
+
+	/* poll for transaction completion */
+	if (smbus_wait_until_done(smbus_io_base) < 0) {
+		return -3;
+	}
+	global_status_register = inb(smbus_io_base + SMBHSTSTAT) & 0x80; /* lose check */;
+
+	if (global_status_register != 0x80) {
+		return -1;
+	}
+	return 0;
+}
+static int do_smbus_read_byte(unsigned smbus_io_base, unsigned device, unsigned address)
+{
+	unsigned char global_status_register;
+	unsigned char byte;
+
+	outb(0xff, smbus_io_base + 0x00);
+	smbus_delay();
+	outb(0x20, smbus_io_base + 0x03);
+	smbus_delay();
+
+	outb(((device & 0x7f) << 1)|1 , smbus_io_base + 0x04);
+	smbus_delay();
+	outb(address & 0xff, smbus_io_base + 0x05);
+	smbus_delay();
+	outb(0x12, smbus_io_base + 0x03);
+	smbus_delay();
+
+int	i,j;
+for(i=0;i<0x1000;i++)
+{
+	if (inb(smbus_io_base + 0x00) != 0x08)
+	{	smbus_delay();
+		for(j=0;j<0xFFFF;j++);
+	}
+};
+
+	global_status_register = inb(smbus_io_base + 0x00); 
+	byte = inb(smbus_io_base + 0x08);
+
+	if (global_status_register != 0x08) { // lose check, otherwise it should be 0
+		print_debug("Fail");print_debug("\r\t");
+			return -1;
+	}
+		print_debug("Success");print_debug("\r\t");	
+	return byte;
+}
+
+
+static int do_smbus_write_byte(unsigned smbus_io_base, unsigned device, unsigned address, unsigned char val)
+{
+	unsigned global_status_register;
+
+	outb(val, smbus_io_base + SMBHSTDAT0);
+	smbus_delay();
+
+	/* set the device I'm talking too */
+	outb(((device & 0x7f) << 1) | 0, smbus_io_base + SMBXMITADD);
+	smbus_delay();
+
+	outb(address & 0xff, smbus_io_base + SMBHSTCMD);
+	smbus_delay();
+
+	/* set up for a byte data write */
+	outb(0x06, smbus_io_base + SMBHSTPRTCL);
+	smbus_delay();
+
+	/* poll for transaction completion */
+	if (smbus_wait_until_done(smbus_io_base) < 0) {
+		return -3;
+	}
+	global_status_register = inb(smbus_io_base + SMBHSTSTAT) & 0x80; /* lose check */;
+
+	if (global_status_register != 0x80) {
+		return -1;
+	}
+	return 0;
+}
+