/*
 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
 *                       <benh@kernel.crashing.org>
 *    and                Arnd Bergmann, 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.
 *
 */

#undef DEBUG

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>

#include <asm/errno.h>
#include <asm/topology.h>
#include <asm/pci-bridge.h>
#include <asm/ppc-pci.h>
#include <asm/atomic.h>

/*
 * The list of OF IDs below is used for matching bus types in the
 * system whose devices are to be exposed as of_platform_devices.
 *
 * This is the default list valid for most platforms. This file provides
 * functions who can take an explicit list if necessary though
 *
 * The search is always performed recursively looking for children of
 * the provided device_node and recursively if such a children matches
 * a bus type in the list
 */

static const struct of_device_id of_default_bus_ids[] = {
        { .type = "soc", },
        { .compatible = "soc", },
        { .type = "spider", },
        { .type = "axon", },
        { .type = "plb5", },
        { .type = "plb4", },
        { .type = "opb", },
        { .type = "ebc", },
        {},
};

struct bus_type of_platform_bus_type = {
       .uevent  = of_device_uevent,
};
EXPORT_SYMBOL(of_platform_bus_type);

static int __init of_bus_driver_init(void)
{
        return of_bus_type_init(&of_platform_bus_type, "of_platform");
}

postcore_initcall(of_bus_driver_init);

struct of_device* of_platform_device_create(struct device_node *np,
                                            const char *bus_id,
                                            struct device *parent)
{
        struct of_device *dev;

        dev = of_device_alloc(np, bus_id, parent);
        if (!dev)
                return NULL;

        dev->dma_mask = 0xffffffffUL;
        dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);

        dev->dev.bus = &of_platform_bus_type;

        /* We do not fill the DMA ops for platform devices by default.
         * This is currently the responsibility of the platform code
         * to do such, possibly using a device notifier
         */

        if (of_device_register(dev) != 0) {
                of_device_free(dev);
                return NULL;
        }

        return dev;
}
EXPORT_SYMBOL(of_platform_device_create);



/**
 * of_platform_bus_create - Create an OF device for a bus node and all its
 * children. Optionally recursively instanciate matching busses.
 * @bus: device node of the bus to instanciate
 * @matches: match table, NULL to use the default, OF_NO_DEEP_PROBE to
 * disallow recursive creation of child busses
 */
static int of_platform_bus_create(const struct device_node *bus,
                                  const struct of_device_id *matches,
                                  struct device *parent)
{
        struct device_node *child;
        struct of_device *dev;
        int rc = 0;

        for_each_child_of_node(bus, child) {
                pr_debug("   create child: %s\n", child->full_name);
                dev = of_platform_device_create(child, NULL, parent);
                if (dev == NULL)
                        rc = -ENOMEM;
                else if (!of_match_node(matches, child))
                        continue;
                if (rc == 0) {
                        pr_debug("   and sub busses\n");
                        rc = of_platform_bus_create(child, matches, &dev->dev);
                } if (rc) {
                        of_node_put(child);
                        break;
                }
        }
        return rc;
}

/**
 * of_platform_bus_probe - Probe the device-tree for platform busses
 * @root: parent of the first level to probe or NULL for the root of the tree
 * @matches: match table, NULL to use the default
 * @parent: parent to hook devices from, NULL for toplevel
 *
 * Note that children of the provided root are not instanciated as devices
 * unless the specified root itself matches the bus list and is not NULL.
 */

int of_platform_bus_probe(struct device_node *root,
                          const struct of_device_id *matches,
                          struct device *parent)
{
        struct device_node *child;
        struct of_device *dev;
        int rc = 0;

        if (matches == NULL)
                matches = of_default_bus_ids;
        if (matches == OF_NO_DEEP_PROBE)
                return -EINVAL;
        if (root == NULL)
                root = of_find_node_by_path("/");
        else
                of_node_get(root);

        pr_debug("of_platform_bus_probe()\n");
        pr_debug(" starting at: %s\n", root->full_name);

        /* Do a self check of bus type, if there's a match, create
         * children
         */
        if (of_match_node(matches, root)) {
                pr_debug(" root match, create all sub devices\n");
                dev = of_platform_device_create(root, NULL, parent);
                if (dev == NULL) {
                        rc = -ENOMEM;
                        goto bail;
                }
                pr_debug(" create all sub busses\n");
                rc = of_platform_bus_create(root, matches, &dev->dev);
                goto bail;
        }
        for_each_child_of_node(root, child) {
                if (!of_match_node(matches, child))
                        continue;

                pr_debug("  match: %s\n", child->full_name);
                dev = of_platform_device_create(child, NULL, parent);
                if (dev == NULL)
                        rc = -ENOMEM;
                else
                        rc = of_platform_bus_create(child, matches, &dev->dev);
                if (rc) {
                        of_node_put(child);
                        break;
                }
        }
 bail:
        of_node_put(root);
        return rc;
}
EXPORT_SYMBOL(of_platform_bus_probe);

static int of_dev_node_match(struct device *dev, void *data)
{
        return to_of_device(dev)->node == data;
}

struct of_device *of_find_device_by_node(struct device_node *np)
{
        struct device *dev;

        dev = bus_find_device(&of_platform_bus_type,
                              NULL, np, of_dev_node_match);
        if (dev)
                return to_of_device(dev);
        return NULL;
}
EXPORT_SYMBOL(of_find_device_by_node);

static int of_dev_phandle_match(struct device *dev, void *data)
{
        phandle *ph = data;
        return to_of_device(dev)->node->linux_phandle == *ph;
}

struct of_device *of_find_device_by_phandle(phandle ph)
{
        struct device *dev;

        dev = bus_find_device(&of_platform_bus_type,
                              NULL, &ph, of_dev_phandle_match);
        if (dev)
                return to_of_device(dev);
        return NULL;
}
EXPORT_SYMBOL(of_find_device_by_phandle);


#ifdef CONFIG_PPC_OF_PLATFORM_PCI

/* The probing of PCI controllers from of_platform is currently
 * 64 bits only, mostly due to gratuitous differences between
 * the 32 and 64 bits PCI code on PowerPC and the 32 bits one
 * lacking some bits needed here.
 */

static int __devinit of_pci_phb_probe(struct of_device *dev,
                                      const struct of_device_id *match)
{
        struct pci_controller *phb;

        /* Check if we can do that ... */
        if (ppc_md.pci_setup_phb == NULL)
                return -ENODEV;

        printk(KERN_INFO "Setting up PCI bus %s\n", dev->node->full_name);

        /* Alloc and setup PHB data structure */
        phb = pcibios_alloc_controller(dev->node);
        if (!phb)
                return -ENODEV;

        /* Setup parent in sysfs */
        phb->parent = &dev->dev;

        /* Setup the PHB using arch provided callback */
        if (ppc_md.pci_setup_phb(phb)) {
                pcibios_free_controller(phb);
                return -ENODEV;
        }

        /* Process "ranges" property */
        pci_process_bridge_OF_ranges(phb, dev->node, 0);

        /* Init pci_dn data structures */
        pci_devs_phb_init_dynamic(phb);

        /* Register devices with EEH */
#ifdef CONFIG_EEH
        if (dev->node->child)
                eeh_add_device_tree_early(dev->node);
#endif /* CONFIG_EEH */

        /* Scan the bus */
        pcibios_scan_phb(phb, dev->node);
        if (phb->bus == NULL)
                return -ENXIO;

        /* Claim resources. This might need some rework as well depending
         * wether we are doing probe-only or not, like assigning unassigned
         * resources etc...
         */
        pcibios_claim_one_bus(phb->bus);

        /* Finish EEH setup */
#ifdef CONFIG_EEH
        eeh_add_device_tree_late(phb->bus);
#endif

        /* Add probed PCI devices to the device model */
        pci_bus_add_devices(phb->bus);

        return 0;
}

static struct of_device_id of_pci_phb_ids[] = {
        { .type = "pci", },
        { .type = "pcix", },
        { .type = "pcie", },
        { .type = "pciex", },
        { .type = "ht", },
        {}
};

static struct of_platform_driver of_pci_phb_driver = {
        .match_table = of_pci_phb_ids,
        .probe = of_pci_phb_probe,
        .driver = {
                .name = "of-pci",
        },
};

static __init int of_pci_phb_init(void)
{
        return of_register_platform_driver(&of_pci_phb_driver);
}

device_initcall(of_pci_phb_init);

#endif /* CONFIG_PPC_OF_PLATFORM_PCI */