/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2003-2004 Linux Networx
 * (Written by Eric Biederman <ebiederman@lnxi.com> for Linux Networx)
 * Copyright (C) 2003 Greg Watson <jarrah@users.sourceforge.net>
 * Copyright (C) 2004 Li-Ta Lo <ollie@lanl.gov>
 * Copyright (C) 2005-2006 Tyan
 * (Written by Yinghai Lu <yhlu@tyan.com> for Tyan)
 *
 * 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 <console/console.h>
#include <device/device.h>
#include <device/path.h>
#include <device/pci.h>
#include <device/pci_def.h>
#include <device/resource.h>

/** Linked list of ALL devices */
DEVTREE_CONST struct device * DEVTREE_CONST all_devices = &dev_root;

/**
 * Given a PCI bus and a devfn number, find the device structure.
 *
 * @param bus The bus number.
 * @param devfn A device/function number.
 * @return Pointer to the device structure (if found), 0 otherwise.
 */
DEVTREE_CONST struct device *dev_find_slot(unsigned int bus,
						unsigned int devfn)
{
	DEVTREE_CONST struct device *dev, *result;

	result = 0;
	for (dev = all_devices; dev; dev = dev->next) {
		if ((dev->path.type == DEVICE_PATH_PCI) &&
		    (dev->bus->secondary == bus) &&
		    (dev->path.pci.devfn == devfn)) {
			result = dev;
			break;
		}
	}
	return result;
}

/**
 * Given a Device Path Type, find the device structure.
 *
 * @param prev_match The previously matched device instance.
 * @param path_type The Device Path Type.
 * @return Pointer to the device structure (if found), 0 otherwise.
 */
DEVTREE_CONST struct device *dev_find_path(
		DEVTREE_CONST struct device *prev_match,
		enum device_path_type path_type)
{
	DEVTREE_CONST struct device *dev, *result = NULL;

	if (prev_match == NULL)
		prev_match = all_devices;
	else
		prev_match = prev_match->next;

	for (dev = prev_match; dev; dev = dev->next) {
		if (dev->path.type == path_type) {
			result = dev;
			break;
		}
	}
	return result;
}

/**
 * Given a device pointer, find the next PCI device.
 *
 * @param previous_dev A pointer to a PCI device structure.
 * @return Pointer to the next device structure (if found), 0 otherwise.
 */
DEVTREE_CONST struct device *dev_find_next_pci_device(
		DEVTREE_CONST struct device *previous_dev)
{
	return dev_find_path(previous_dev, DEVICE_PATH_PCI);
}

static int path_eq(const struct device_path *path1,
		const struct device_path *path2)
{
	int equal = 0;

	if (path1->type != path2->type)
		return 0;

	switch (path1->type) {
	case DEVICE_PATH_NONE:
		break;
	case DEVICE_PATH_ROOT:
		equal = 1;
		break;
	case DEVICE_PATH_PCI:
		equal = (path1->pci.devfn == path2->pci.devfn);
		break;
	case DEVICE_PATH_PNP:
		equal = (path1->pnp.port == path2->pnp.port) &&
			(path1->pnp.device == path2->pnp.device);
		break;
	case DEVICE_PATH_I2C:
		equal = (path1->i2c.device == path2->i2c.device) &&
			(path1->i2c.mode_10bit == path2->i2c.mode_10bit);
		break;
	case DEVICE_PATH_APIC:
		equal = (path1->apic.apic_id == path2->apic.apic_id);
		break;
	case DEVICE_PATH_DOMAIN:
		equal = (path1->domain.domain == path2->domain.domain);
		break;
	case DEVICE_PATH_CPU_CLUSTER:
		equal = (path1->cpu_cluster.cluster
			 == path2->cpu_cluster.cluster);
		break;
	case DEVICE_PATH_CPU:
		equal = (path1->cpu.id == path2->cpu.id);
		break;
	case DEVICE_PATH_CPU_BUS:
		equal = (path1->cpu_bus.id == path2->cpu_bus.id);
		break;
	case DEVICE_PATH_GENERIC:
		equal = (path1->generic.id == path2->generic.id) &&
			(path1->generic.subid == path2->generic.subid);
		break;
	case DEVICE_PATH_SPI:
		equal = (path1->spi.cs == path2->spi.cs);
		break;
	case DEVICE_PATH_USB:
		equal = (path1->usb.port_type == path2->usb.port_type) &&
			(path1->usb.port_id == path2->usb.port_id);
		break;
	case DEVICE_PATH_MMIO:
		equal = (path1->mmio.addr == path2->mmio.addr);
		break;
	default:
		printk(BIOS_ERR, "Unknown device type: %d\n", path1->type);
		break;
	}

	return equal;
}

/**
 * See if a device structure exists for path.
 *
 * @param parent The bus to find the device on.
 * @param path The relative path from the bus to the appropriate device.
 * @return Pointer to a device structure for the device on bus at path
 *         or 0/NULL if no device is found.
 */
DEVTREE_CONST struct device *find_dev_path(
	const struct bus *parent, const struct device_path *path)
{
	DEVTREE_CONST struct device *child;
	for (child = parent->children; child; child = child->sibling) {
		if (path_eq(path, &child->path))
			break;
	}
	return child;
}

DEVTREE_CONST struct device *pcidev_path_behind(
	const struct bus *parent, pci_devfn_t devfn)
{
	const struct device_path path = {
		.type = DEVICE_PATH_PCI,
		.pci.devfn = devfn,
	};
	return find_dev_path(parent, &path);
}

DEVTREE_CONST struct device *pcidev_path_on_root(pci_devfn_t devfn)
{
	DEVTREE_CONST struct device *pci_domain;

	/* Work around pcidev_path_behind() below failing
	 * due tue complicated devicetree with topology
	 * being manipulated on-the-fly.
	 */
	if (CONFIG(NORTHBRIDGE_AMD_AMDFAM10))
		return dev_find_slot(0, devfn);

	pci_domain = dev_find_path(NULL, DEVICE_PATH_DOMAIN);
	if (!pci_domain)
		return NULL;

	return pcidev_path_behind(pci_domain->link_list, devfn);
}

DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn)
{
	return pcidev_path_on_root(PCI_DEVFN(dev, fn));
}

/**
 * Given an SMBus bus and a device number, find the device structure.
 *
 * @param bus The bus number.
 * @param addr A device number.
 * @return Pointer to the device structure (if found), 0 otherwise.
 */
DEVTREE_CONST struct device *dev_find_slot_on_smbus(unsigned int bus,
							unsigned int addr)
{
	DEVTREE_CONST struct device *dev, *result;

	result = 0;
	for (dev = all_devices; dev; dev = dev->next) {
		if ((dev->path.type == DEVICE_PATH_I2C) &&
		    (dev->bus->secondary == bus) &&
		    (dev->path.i2c.device == addr)) {
			result = dev;
			break;
		}
	}
	return result;
}

/**
 * Given a PnP port and a device number, find the device structure.
 *
 * @param port The I/O port.
 * @param device Logical device number.
 * @return Pointer to the device structure (if found), 0 otherwise.
 */
DEVTREE_CONST struct device *dev_find_slot_pnp(u16 port, u16 device)
{
	DEVTREE_CONST struct device *dev;

	for (dev = all_devices; dev; dev = dev->next) {
		if ((dev->path.type == DEVICE_PATH_PNP) &&
		    (dev->path.pnp.port == port) &&
		    (dev->path.pnp.device == device)) {
			return dev;
		}
	}
	return 0;
}

/**
 * Given a device and previous match iterate through all the children.
 *
 * @param bus parent device's bus holding all the children
 * @param prev_child previous child already traversed, if NULL start at
 *        children of parent bus.
 * @return pointer to child or NULL when no more children
 */
DEVTREE_CONST struct device *dev_bus_each_child(const struct bus *parent,
					DEVTREE_CONST struct device *prev_child)
{
	DEVTREE_CONST struct device *dev;

	if (parent == NULL)
		return NULL;

	if (prev_child == NULL)
		dev = parent->children;
	else
		dev = prev_child->sibling;

	return dev;
}