/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2008 Joseph Smith <joe@smittys.pointclark.net>
 *
 * 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 <console/console.h>
#include <arch/io.h>
#include <stdint.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_ids.h>
#include <cpu/cpu.h>
#include <stdlib.h>
#include <string.h>
#include <bitops.h>
#include "chip.h"
#include "i82830.h"

static void northbridge_init(device_t dev)
{
	printk_spew("Northbridge init\n");
}

static struct device_operations northbridge_operations = {
	.read_resources = pci_dev_read_resources,
	.set_resources = pci_dev_set_resources,
	.enable_resources = pci_dev_enable_resources,
	.init = northbridge_init,
	.enable = 0,
	.ops_pci = 0,
};

static struct pci_driver northbridge_driver __pci_driver = {
	.ops = &northbridge_operations,
	.vendor = PCI_VENDOR_ID_INTEL,
	.device = 0x3575,
};

static void ram_resource(device_t dev, unsigned long index,
			 unsigned long basek, unsigned long sizek)
{
	struct resource *resource;

	if (!sizek)
		return;
	resource = new_resource(dev, index);
	resource->base = ((resource_t) basek) << 10;
	resource->size = ((resource_t) sizek) << 10;
	resource->flags = IORESOURCE_MEM | IORESOURCE_CACHEABLE |
	    IORESOURCE_FIXED | IORESOURCE_STORED | IORESOURCE_ASSIGNED;
}

static void tolm_test(void *gp, struct device *dev, struct resource *new)
{
	struct resource **best_p = gp;
	struct resource *best;
	best = *best_p;
	if (!best || (best->base > new->base))
		best = new;
	*best_p = best;
}

static uint32_t find_pci_tolm(struct bus *bus)
{
	struct resource *min;
	uint32_t tolm;
	min = 0;
	search_bus_resources(bus, IORESOURCE_MEM, IORESOURCE_MEM, tolm_test,
			     &min);
	tolm = 0xffffffffUL;
	if (min && tolm > min->base)
		tolm = min->base;
	return tolm;
}

#if CONFIG_WRITE_HIGH_TABLES==1
#define HIGH_TABLES_SIZE 64	// maximum size of high tables in KB
extern uint64_t high_tables_base, high_tables_size;
#endif
static void pci_domain_set_resources(device_t dev)
{
	device_t mc_dev;
	uint32_t pci_tolm;
	int igd_memory = 0;

	pci_tolm = find_pci_tolm(&dev->link[0]);
	mc_dev = dev->link[0].children;
	if (mc_dev) {
		unsigned long tomk, tolmk;
		int idx;

		if (CONFIG_VIDEO_MB == 512) {
			igd_memory = (CONFIG_VIDEO_MB);
		} else {
			igd_memory = (CONFIG_VIDEO_MB * 1024);
		}

		/* Get the value of the highest DRB. This tells the end of
		 * the physical memory. The units are ticks of 32MB
		 * i.e. 1 means 32MB.
		 */
		tomk = ((unsigned long)pci_read_config8(mc_dev, DRB + 3)) << 15;
		tomk -= igd_memory;
		printk_debug("Setting RAM size to %d\n", tomk);

		/* Compute the top of low memory. */
		tolmk = pci_tolm >> 10;
		if (tolmk >= tomk) {
			/* The PCI hole does does not overlap the memory. */
			tolmk = tomk;
		}

		/* Report the memory regions. */
		idx = 10;
		ram_resource(dev, idx++, 0, 640);
		ram_resource(dev, idx++, 1024, tolmk - 1024);

#if CONFIG_WRITE_HIGH_TABLES==1
		/* Leave some space for ACPI, PIRQ and MP tables */
		high_tables_base = (tomk - HIGH_TABLES_SIZE) * 1024;
		high_tables_size = HIGH_TABLES_SIZE * 1024;
#endif
	}
	assign_resources(&dev->link[0]);
}

static struct device_operations pci_domain_ops = {
	.read_resources		= pci_domain_read_resources,
	.set_resources		= pci_domain_set_resources,
	.enable_resources	= enable_childrens_resources,
	.init			= 0,
	.scan_bus		= pci_domain_scan_bus,
};

static void cpu_bus_init(device_t dev)
{
	initialize_cpus(&dev->link[0]);
}

static void cpu_bus_noop(device_t dev)
{
}

static struct device_operations cpu_bus_ops = {
	.read_resources		= cpu_bus_noop,
	.set_resources		= cpu_bus_noop,
	.enable_resources	= cpu_bus_noop,
	.init			= cpu_bus_init,
	.scan_bus		= 0,
};

static void enable_dev(struct device *dev)
{
	struct device_path;

	/* Set the operations if it is a special bus type. */
	if (dev->path.type == DEVICE_PATH_PCI_DOMAIN) {
		dev->ops = &pci_domain_ops;
		pci_set_method(dev);
	} else if (dev->path.type == DEVICE_PATH_APIC_CLUSTER) {
		dev->ops = &cpu_bus_ops;
	}
}

struct chip_operations northbridge_intel_i82830_ops = {
	CHIP_NAME("Intel 82830 Northbridge")
	.enable_dev = enable_dev,
};
