/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2007 Rudolf Marek <r.marek@assembler.cz>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License v2 as published by
 * the Free Software Foundation.
 *
 * 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/device.h>
#include <device/pci.h>
#include <device/pci_ops.h>
#include <device/pci_ids.h>
#include <console/console.h>

/**
 * Setup the V-Link for VT8237R, 8X mode.
 *
 * For K8T890CF VIA recommends what is in VIA column, AW is award 8X:
 *
 *						 REG   DEF   AW  VIA-8X VIA-4X
 *						 -----------------------------
 * NB V-Link Manual Driving Control strobe	 0xb5  0x46  0x46  0x88  0x88
 * NB V-Link Manual Driving Control - Data	 0xb6  0x46  0x46  0x88  0x88
 * NB V-Link Receiving Strobe Delay		 0xb7  0x02  0x02  0x61  0x01
 * NB V-Link Compensation Control bit4,0 (b5,b6) 0xb4  0x10  0x10  0x11  0x11
 * SB V-Link Strobe Drive Control 		 0xb9  0x00  0xa5  0x98  0x98
 * SB V-Link Data drive Control????		 0xba  0x00  0xbb  0x77  0x77
 * SB V-Link Receive Strobe Delay????		 0xbb  0x04  0x11  0x11  0x11
 * SB V-Link Compensation Control bit0 (use b9)	 0xb8  0x00  0x01  0x01  0x01
 * V-Link CKG Control				 0xb0  0x05  0x05  0x06  0x03
 * V-Link CKG Control				 0xb1  0x05  0x05  0x01  0x03
 */
static void ctrl_init_vt8237r(struct device *dev)
{
	u8 reg;

	/*
	 * This init code is valid only for the VT8237R! For different
	 * sounthbridges (e.g. VT8237A, VT8237S, VT8237 (without plus R)
	 * and VT8251) a different init code is required.
	 */
	device_t devsb = dev_find_device(PCI_VENDOR_ID_VIA,
					 PCI_DEVICE_ID_VIA_VT8237R_LPC, 0);
	if (!devsb)
		return;

	pci_write_config8(dev, 0xb5, 0x88);
	pci_write_config8(dev, 0xb6, 0x88);
	pci_write_config8(dev, 0xb7, 0x61);

	reg = pci_read_config8(dev, 0xb4);
	reg |= 0x11;
	pci_write_config8(dev, 0xb4, reg);

	pci_write_config8(dev, 0xb9, 0x98);
	pci_write_config8(dev, 0xba, 0x77);
	pci_write_config8(dev, 0xbb, 0x11);

	reg = pci_read_config8(dev, 0xb8);
	reg |= 0x1;
	pci_write_config8(dev, 0xb8, reg);

	pci_write_config8(dev, 0xb0, 0x06);
	pci_write_config8(dev, 0xb1, 0x01);

	/* Program V-link 8X 16bit full duplex, parity enabled. */
	pci_write_config8(dev, 0x48, 0xa3);
}

static void ctrl_enable(struct device *dev)
{
	u8 regm, regm2, regm3;
	device_t devfun3 = dev_find_device(PCI_VENDOR_ID_VIA,
					   PCI_DEVICE_ID_VIA_K8T890CE_3, 0);

	/* TODO: Fix some ordering issue fo V-link set Rx77[6] and PCI1_Rx4F[0]
	   should to 1 */

	/* C2P Read ACK Return Priority */
	/* PCI CFG Address bits[27:24] are used as extended register address
	   bit[11:8] */
	pci_write_config8(dev, 0x47, 0x30);
	/* Magic init. This is not well documented :/ */
	pci_write_config8(dev, 0x70, 0xc2);

	/* PCI Control */
	pci_write_config8(dev, 0x72, 0xee);
	pci_write_config8(dev, 0x73, 0x01);
	pci_write_config8(dev, 0x74, 0x24);
	pci_write_config8(dev, 0x75, 0x0f);
	pci_write_config8(dev, 0x76, 0x50);
	pci_write_config8(dev, 0x77, 0x08);
	pci_write_config8(dev, 0x78, 0x01);
	/* APIC on HT */
	pci_write_config8(dev, 0x7c, 0x7f);
	pci_write_config8(dev, 0x7f, 0x02);

	/* WARNING: Need to copy some registers from NB (D0F3) to SB (D0F7). */

	regm = pci_read_config8(devfun3, 0x88);	/* Shadow mem CTRL */
	pci_write_config8(dev, 0x57, regm);

	regm = pci_read_config8(devfun3, 0x80);	/* Shadow page C */
	pci_write_config8(dev, 0x61, regm);

	regm = pci_read_config8(devfun3, 0x81);	/* Shadow page D */
	pci_write_config8(dev, 0x62, regm);

	regm = pci_read_config8(devfun3, 0x86);	/* SMM and APIC decoding */
	pci_write_config8(dev, 0xe6, regm);

	regm3 = pci_read_config8(devfun3, 0x82);/* Shadow page E */

	/*
	 * All access bits for 0xE0000-0xEFFFF encode as just 2 bits!
	 * So the NB reg is quite inconsistent, we expect there only 0xff or 0x00,
	 * and write them to 0x63 7-6 but! VIA 8237A has the mirror at 0x64!
	 */
	if (regm3 == 0xff)
		regm3 = 0xc0;
	else
		regm3 = 0x0;

	/* Shadow page F + memhole copy */
	regm = pci_read_config8(devfun3, 0x83);
	pci_write_config8(dev, 0x63, regm3 | (regm & 0x3F));
}

static const struct device_operations ctrl_ops = {
	.read_resources		= pci_dev_read_resources,
	.set_resources		= pci_dev_set_resources,
	.enable_resources	= pci_dev_enable_resources,
	.enable			= ctrl_enable,
	.init			= ctrl_init_vt8237r,
	.ops_pci		= 0,
};

static const struct pci_driver northbridge_driver __pci_driver = {
	.ops	= &ctrl_ops,
	.vendor	= PCI_VENDOR_ID_VIA,
	.device	= PCI_DEVICE_ID_VIA_K8T890CE_7,
};
