/*
 * PCI <-> OF mapping helpers
 *
 * Copyright 2011 IBM Corp.
 *
 * 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.
 */

#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include "pci.h"

void pci_set_of_node(struct pci_dev *dev)
{
	if (!dev->bus->dev.of_node)
		return;
	dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
						    dev->devfn);
}

void pci_release_of_node(struct pci_dev *dev)
{
	of_node_put(dev->dev.of_node);
	dev->dev.of_node = NULL;
}

void pci_set_bus_of_node(struct pci_bus *bus)
{
	if (bus->self == NULL)
		bus->dev.of_node = pcibios_get_phb_of_node(bus);
	else
		bus->dev.of_node = of_node_get(bus->self->dev.of_node);
}

void pci_release_bus_of_node(struct pci_bus *bus)
{
	of_node_put(bus->dev.of_node);
	bus->dev.of_node = NULL;
}

struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
{
	/* This should only be called for PHBs */
	if (WARN_ON(bus->self || bus->parent))
		return NULL;

	/* Look for a node pointer in either the intermediary device we
	 * create above the root bus or it's own parent. Normally only
	 * the later is populated.
	 */
	if (bus->bridge->of_node)
		return of_node_get(bus->bridge->of_node);
	if (bus->bridge->parent && bus->bridge->parent->of_node)
		return of_node_get(bus->bridge->parent->of_node);
	return NULL;
}

struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus)
{
#ifdef CONFIG_IRQ_DOMAIN
	struct irq_domain *d;

	if (!bus->dev.of_node)
		return NULL;

	/* Start looking for a phandle to an MSI controller. */
	d = of_msi_get_domain(&bus->dev, bus->dev.of_node, DOMAIN_BUS_PCI_MSI);
	if (d)
		return d;

	/*
	 * If we don't have an msi-parent property, look for a domain
	 * directly attached to the host bridge.
	 */
	d = irq_find_matching_host(bus->dev.of_node, DOMAIN_BUS_PCI_MSI);
	if (d)
		return d;

	return irq_find_host(bus->dev.of_node);
#else
	return NULL;
#endif
}

int pci_parse_request_of_pci_ranges(struct device *dev,
				    struct list_head *resources,
				    struct resource **bus_range)
{
	int err, res_valid = 0;
	struct device_node *np = dev->of_node;
	resource_size_t iobase;
	struct resource_entry *win, *tmp;

	INIT_LIST_HEAD(resources);
	err = of_pci_get_host_bridge_resources(np, 0, 0xff, resources, &iobase);
	if (err)
		return err;

	err = devm_request_pci_bus_resources(dev, resources);
	if (err)
		goto out_release_res;

	resource_list_for_each_entry_safe(win, tmp, resources) {
		struct resource *res = win->res;

		switch (resource_type(res)) {
		case IORESOURCE_IO:
			err = pci_remap_iospace(res, iobase);
			if (err) {
				dev_warn(dev, "error %d: failed to map resource %pR\n",
					 err, res);
				resource_list_destroy_entry(win);
			}
			break;
		case IORESOURCE_MEM:
			res_valid |= !(res->flags & IORESOURCE_PREFETCH);
			break;
		case IORESOURCE_BUS:
			if (bus_range)
				*bus_range = res;
			break;
		}
	}

	if (res_valid)
		return 0;

	dev_err(dev, "non-prefetchable memory resource required\n");
	err = -EINVAL;

 out_release_res:
	pci_free_resource_list(resources);
	return err;
}