[POWERPC] pci32: Remove PowerMac P2P bridge IO hack

[linux-2.6.git] / arch / powerpc / kernel / pci_32.c

/*
 * Common pmac/prep/chrp pci routines. -- Cort
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/capability.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/bootmem.h>
#include <linux/irq.h>
#include <linux/list.h>

#include <asm/processor.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/sections.h>
#include <asm/pci-bridge.h>
#include <asm/byteorder.h>
#include <asm/uaccess.h>
#include <asm/machdep.h>

#undef DEBUG

#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif

unsigned long isa_io_base     = 0;
unsigned long pci_dram_offset = 0;
int pcibios_assign_bus_offset = 1;

void pcibios_make_OF_bus_map(void);

static void pcibios_fixup_resources(struct pci_dev* dev);
static void fixup_broken_pcnet32(struct pci_dev* dev);
static int reparent_resources(struct resource *parent, struct resource *res);
static void fixup_cpc710_pci64(struct pci_dev* dev);
#ifdef CONFIG_PPC_OF
static u8* pci_to_OF_bus_map;
#endif

/* By default, we don't re-assign bus numbers. We do this only on
 * some pmacs
 */
int pci_assign_all_buses;

LIST_HEAD(hose_list);

static int pci_bus_count;

static void
fixup_hide_host_resource_fsl(struct pci_dev* dev)
{
        int i, class = dev->class >> 8;

        if ((class == PCI_CLASS_PROCESSOR_POWERPC) &&
                (dev->hdr_type == PCI_HEADER_TYPE_NORMAL) &&
                (dev->bus->parent == NULL)) {
                for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
                        dev->resource[i].start = 0;
                        dev->resource[i].end = 0;
                        dev->resource[i].flags = 0;
                }
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MOTOROLA, PCI_ANY_ID, fixup_hide_host_resource_fsl); 
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_FREESCALE, PCI_ANY_ID, fixup_hide_host_resource_fsl); 

static void
fixup_broken_pcnet32(struct pci_dev* dev)
{
        if ((dev->class>>8 == PCI_CLASS_NETWORK_ETHERNET)) {
                dev->vendor = PCI_VENDOR_ID_AMD;
                pci_write_config_word(dev, PCI_VENDOR_ID, PCI_VENDOR_ID_AMD);
        }
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TRIDENT, PCI_ANY_ID,                     fixup_broken_pcnet32);

static void
fixup_cpc710_pci64(struct pci_dev* dev)
{
        /* Hide the PCI64 BARs from the kernel as their content doesn't
         * fit well in the resource management
         */
        dev->resource[0].start = dev->resource[0].end = 0;
        dev->resource[0].flags = 0;
        dev->resource[1].start = dev->resource[1].end = 0;
        dev->resource[1].flags = 0;
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM,     PCI_DEVICE_ID_IBM_CPC710_PCI64, fixup_cpc710_pci64);

static void
pcibios_fixup_resources(struct pci_dev *dev)
{
        struct pci_controller* hose = (struct pci_controller *)dev->sysdata;
        int i;
        resource_size_t offset, mask;

        if (!hose) {
                printk(KERN_ERR "No hose for PCI dev %s!\n", pci_name(dev));
                return;
        }
        for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
                struct resource *res = dev->resource + i;
                if (!res->flags)
                        continue;
                if (res->end == 0xffffffff) {
                        DBG("PCI:%s Resource %d [%016llx-%016llx] is unassigned\n",
                            pci_name(dev), i, (u64)res->start, (u64)res->end);
                        res->end -= res->start;
                        res->start = 0;
                        res->flags |= IORESOURCE_UNSET;
                        continue;
                }
                offset = 0;
                mask = (resource_size_t)-1;
                if (res->flags & IORESOURCE_MEM) {
                        offset = hose->pci_mem_offset;
                } else if (res->flags & IORESOURCE_IO) {
                        offset = (unsigned long) hose->io_base_virt
                                - isa_io_base;
                        mask = 0xffffffffu;
                }
                if (offset != 0) {
                        res->start = (res->start + offset) & mask;
                        res->end = (res->end + offset) & mask;
                        DBG("PCI: Fixup res %d (0x%lx) of dev %s: %llx -> %llx\n",
                            i, res->flags, pci_name(dev),
                            (u64)res->start - offset, (u64)res->start);
                }
        }

        /* Call machine specific resource fixup */
        if (ppc_md.pcibios_fixup_resources)
                ppc_md.pcibios_fixup_resources(dev);
}
DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID,            PCI_ANY_ID,                     pcibios_fixup_resources);

void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
                        struct resource *res)
{
        resource_size_t offset = 0, mask = (resource_size_t)-1;
        struct pci_controller *hose = dev->sysdata;

        if (hose && res->flags & IORESOURCE_IO) {
                offset = (unsigned long)hose->io_base_virt - isa_io_base;
                mask = 0xffffffffu;
        } else if (hose && res->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;
        region->start = (res->start - offset) & mask;
        region->end = (res->end - offset) & mask;
}
EXPORT_SYMBOL(pcibios_resource_to_bus);

void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
                             struct pci_bus_region *region)
{
        resource_size_t offset = 0, mask = (resource_size_t)-1;
        struct pci_controller *hose = dev->sysdata;

        if (hose && res->flags & IORESOURCE_IO) {
                offset = (unsigned long)hose->io_base_virt - isa_io_base;
                mask = 0xffffffffu;
        } else if (hose && res->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;
        res->start = (region->start + offset) & mask;
        res->end = (region->end + offset) & mask;
}
EXPORT_SYMBOL(pcibios_bus_to_resource);

/*
 * We need to avoid collisions with `mirrored' VGA ports
 * and other strange ISA hardware, so we always want the
 * addresses to be allocated in the 0x000-0x0ff region
 * modulo 0x400.
 *
 * Why? Because some silly external IO cards only decode
 * the low 10 bits of the IO address. The 0x00-0xff region
 * is reserved for motherboard devices that decode all 16
 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
 * but we want to try to avoid allocating at 0x2900-0x2bff
 * which might have be mirrored at 0x0100-0x03ff..
 */
void pcibios_align_resource(void *data, struct resource *res,
                                resource_size_t size, resource_size_t align)
{
        struct pci_dev *dev = data;

        if (res->flags & IORESOURCE_IO) {
                resource_size_t start = res->start;

                if (start & 0x300) {
                        start = (start + 0x3ff) & ~0x3ff;
                        res->start = start;
                }
        }
}
EXPORT_SYMBOL(pcibios_align_resource);

/*
 *  Handle resources of PCI devices.  If the world were perfect, we could
 *  just allocate all the resource regions and do nothing more.  It isn't.
 *  On the other hand, we cannot just re-allocate all devices, as it would
 *  require us to know lots of host bridge internals.  So we attempt to
 *  keep as much of the original configuration as possible, but tweak it
 *  when it's found to be wrong.
 *
 *  Known BIOS problems we have to work around:
 *      - I/O or memory regions not configured
 *      - regions configured, but not enabled in the command register
 *      - bogus I/O addresses above 64K used
 *      - expansion ROMs left enabled (this may sound harmless, but given
 *        the fact the PCI specs explicitly allow address decoders to be
 *        shared between expansion ROMs and other resource regions, it's
 *        at least dangerous)
 *
 *  Our solution:
 *      (1) Allocate resources for all buses behind PCI-to-PCI bridges.
 *          This gives us fixed barriers on where we can allocate.
 *      (2) Allocate resources for all enabled devices.  If there is
 *          a collision, just mark the resource as unallocated. Also
 *          disable expansion ROMs during this step.
 *      (3) Try to allocate resources for disabled devices.  If the
 *          resources were assigned correctly, everything goes well,
 *          if they weren't, they won't disturb allocation of other
 *          resources.
 *      (4) Assign new addresses to resources which were either
 *          not configured at all or misconfigured.  If explicitly
 *          requested by the user, configure expansion ROM address
 *          as well.
 */

static void __init
pcibios_allocate_bus_resources(struct list_head *bus_list)
{
        struct pci_bus *bus;
        int i;
        struct resource *res, *pr;

        /* Depth-First Search on bus tree */
        list_for_each_entry(bus, bus_list, node) {
                for (i = 0; i < 4; ++i) {
                        if ((res = bus->resource[i]) == NULL || !res->flags
                            || res->start > res->end)
                                continue;
                        if (bus->parent == NULL)
                                pr = (res->flags & IORESOURCE_IO)?
                                        &ioport_resource: &iomem_resource;
                        else {
                                pr = pci_find_parent_resource(bus->self, res);
                                if (pr == res) {
                                        /* this happens when the generic PCI
                                         * code (wrongly) decides that this
                                         * bridge is transparent  -- paulus
                                         */
                                        continue;
                                }
                        }

                        DBG("PCI: dev %s (bus 0x%02x) bridge rsrc %d: %016llx..%016llx "
                            "(f:0x%08lx), parent %p\n",
                            bus->self ? pci_name(bus->self) : "PHB", bus->number, i,
                            (u64)res->start, (u64)res->end, res->flags, pr);

                        if (pr && !(pr->flags & IORESOURCE_UNSET)) {
                                if (request_resource(pr, res) == 0)
                                        continue;
                                /*
                                 * Must be a conflict with an existing entry.
                                 * Move that entry (or entries) under the
                                 * bridge resource and try again.
                                 */
                                if (reparent_resources(pr, res) == 0)
                                        continue;
                        }
                        printk(KERN_WARNING
                               "PCI: Cannot allocate resource region "
                               "%d of PCI bridge %d, will remap\n",
                               i, bus->number);
                        res->flags |= IORESOURCE_UNSET;
                }
                pcibios_allocate_bus_resources(&bus->children);
        }
}

/*
 * Reparent resource children of pr that conflict with res
 * under res, and make res replace those children.
 */
static int __init
reparent_resources(struct resource *parent, struct resource *res)
{
        struct resource *p, **pp;
        struct resource **firstpp = NULL;

        for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
                if (p->end < res->start)
                        continue;
                if (res->end < p->start)
                        break;
                if (p->start < res->start || p->end > res->end)
                        return -1;      /* not completely contained */
                if (firstpp == NULL)
                        firstpp = pp;
        }
        if (firstpp == NULL)
                return -1;      /* didn't find any conflicting entries? */
        res->parent = parent;
        res->child = *firstpp;
        res->sibling = *pp;
        *firstpp = res;
        *pp = NULL;
        for (p = res->child; p != NULL; p = p->sibling) {
                p->parent = res;
                DBG(KERN_INFO "PCI: reparented %s [%llx..%llx] under %s\n",
                    p->name, (u64)p->start, (u64)p->end, res->name);
        }
        return 0;
}

void __init
update_bridge_resource(struct pci_dev *dev, struct resource *res)
{
        u8 io_base_lo, io_limit_lo;
        u16 mem_base, mem_limit;
        u16 cmd;
        resource_size_t start, end, off;
        struct pci_controller *hose = dev->sysdata;

        if (!hose) {
                printk("update_bridge_base: no hose?\n");
                return;
        }
        pci_read_config_word(dev, PCI_COMMAND, &cmd);
        pci_write_config_word(dev, PCI_COMMAND,
                              cmd & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY));
        if (res->flags & IORESOURCE_IO) {
                off = (unsigned long) hose->io_base_virt - isa_io_base;
                start = res->start - off;
                end = res->end - off;
                io_base_lo = (start >> 8) & PCI_IO_RANGE_MASK;
                io_limit_lo = (end >> 8) & PCI_IO_RANGE_MASK;
                if (end > 0xffff)
                        io_base_lo |= PCI_IO_RANGE_TYPE_32;
                else
                        io_base_lo |= PCI_IO_RANGE_TYPE_16;
                pci_write_config_word(dev, PCI_IO_BASE_UPPER16,
                                start >> 16);
                pci_write_config_word(dev, PCI_IO_LIMIT_UPPER16,
                                end >> 16);
                pci_write_config_byte(dev, PCI_IO_BASE, io_base_lo);
                pci_write_config_byte(dev, PCI_IO_LIMIT, io_limit_lo);

        } else if ((res->flags & (IORESOURCE_MEM | IORESOURCE_PREFETCH))
                   == IORESOURCE_MEM) {
                off = hose->pci_mem_offset;
                mem_base = ((res->start - off) >> 16) & PCI_MEMORY_RANGE_MASK;
                mem_limit = ((res->end - off) >> 16) & PCI_MEMORY_RANGE_MASK;
                pci_write_config_word(dev, PCI_MEMORY_BASE, mem_base);
                pci_write_config_word(dev, PCI_MEMORY_LIMIT, mem_limit);

        } else if ((res->flags & (IORESOURCE_MEM | IORESOURCE_PREFETCH))
                   == (IORESOURCE_MEM | IORESOURCE_PREFETCH)) {
                off = hose->pci_mem_offset;
                mem_base = ((res->start - off) >> 16) & PCI_PREF_RANGE_MASK;
                mem_limit = ((res->end - off) >> 16) & PCI_PREF_RANGE_MASK;
                pci_write_config_word(dev, PCI_PREF_MEMORY_BASE, mem_base);
                pci_write_config_word(dev, PCI_PREF_MEMORY_LIMIT, mem_limit);

        } else {
                DBG(KERN_ERR "PCI: ugh, bridge %s res has flags=%lx\n",
                    pci_name(dev), res->flags);
        }
        pci_write_config_word(dev, PCI_COMMAND, cmd);
}

static inline void alloc_resource(struct pci_dev *dev, int idx)
{
        struct resource *pr, *r = &dev->resource[idx];

        DBG("PCI: Allocating %s: Resource %d: %016llx..%016llx (f=%lx)\n",
            pci_name(dev), idx, (u64)r->start, (u64)r->end, r->flags);
        pr = pci_find_parent_resource(dev, r);
        if (!pr || (pr->flags & IORESOURCE_UNSET) ||  request_resource(pr, r) < 0) {
                printk(KERN_WARNING "PCI: Cannot allocate resource region %d"
                       " of device %s, will remap\n", idx, pci_name(dev));
                if (pr)
                        DBG("PCI:  parent is %p: %016llx-%016llx (f=%lx)\n",
                            pr, (u64)pr->start, (u64)pr->end, pr->flags);
                /* We'll assign a new address later */
                r->flags |= IORESOURCE_UNSET;
                r->end -= r->start;
                r->start = 0;
        }
}

static void __init
pcibios_allocate_resources(int pass)
{
        struct pci_dev *dev = NULL;
        int idx, disabled;
        u16 command;
        struct resource *r;

        for_each_pci_dev(dev) {
                pci_read_config_word(dev, PCI_COMMAND, &command);
                for (idx = 0; idx < 6; idx++) {
                        r = &dev->resource[idx];
                        if (r->parent)          /* Already allocated */
                                continue;
                        if (!r->flags || (r->flags & IORESOURCE_UNSET))
                                continue;       /* Not assigned at all */
                        if (r->flags & IORESOURCE_IO)
                                disabled = !(command & PCI_COMMAND_IO);
                        else
                                disabled = !(command & PCI_COMMAND_MEMORY);
                        if (pass == disabled)
                                alloc_resource(dev, idx);
                }
                if (pass)
                        continue;
                r = &dev->resource[PCI_ROM_RESOURCE];
                if (r->flags & IORESOURCE_ROM_ENABLE) {
                        /* Turn the ROM off, leave the resource region, but keep it unregistered. */
                        u32 reg;
                        DBG("PCI: Switching off ROM of %s\n", pci_name(dev));
                        r->flags &= ~IORESOURCE_ROM_ENABLE;
                        pci_read_config_dword(dev, dev->rom_base_reg, &reg);
                        pci_write_config_dword(dev, dev->rom_base_reg,
                                               reg & ~PCI_ROM_ADDRESS_ENABLE);
                }
        }
}

#ifdef CONFIG_PPC_OF
/*
 * Functions below are used on OpenFirmware machines.
 */
static void
make_one_node_map(struct device_node* node, u8 pci_bus)
{
        const int *bus_range;
        int len;

        if (pci_bus >= pci_bus_count)
                return;
        bus_range = of_get_property(node, "bus-range", &len);
        if (bus_range == NULL || len < 2 * sizeof(int)) {
                printk(KERN_WARNING "Can't get bus-range for %s, "
                       "assuming it starts at 0\n", node->full_name);
                pci_to_OF_bus_map[pci_bus] = 0;
        } else
                pci_to_OF_bus_map[pci_bus] = bus_range[0];

        for (node=node->child; node != 0;node = node->sibling) {
                struct pci_dev* dev;
                const unsigned int *class_code, *reg;
        
                class_code = of_get_property(node, "class-code", NULL);
                if (!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
                        (*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS))
                        continue;
                reg = of_get_property(node, "reg", NULL);
                if (!reg)
                        continue;
                dev = pci_get_bus_and_slot(pci_bus, ((reg[0] >> 8) & 0xff));
                if (!dev || !dev->subordinate) {
                        pci_dev_put(dev);
                        continue;
                }
                make_one_node_map(node, dev->subordinate->number);
                pci_dev_put(dev);
        }
}
        
void
pcibios_make_OF_bus_map(void)
{
        int i;
        struct pci_controller *hose, *tmp;
        struct property *map_prop;
        struct device_node *dn;

        pci_to_OF_bus_map = kmalloc(pci_bus_count, GFP_KERNEL);
        if (!pci_to_OF_bus_map) {
                printk(KERN_ERR "Can't allocate OF bus map !\n");
                return;
        }

        /* We fill the bus map with invalid values, that helps
         * debugging.
         */
        for (i=0; i<pci_bus_count; i++)
                pci_to_OF_bus_map[i] = 0xff;

        /* For each hose, we begin searching bridges */
        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
                struct device_node* node = hose->dn;

                if (!node)
                        continue;
                make_one_node_map(node, hose->first_busno);
        }
        dn = of_find_node_by_path("/");
        map_prop = of_find_property(dn, "pci-OF-bus-map", NULL);
        if (map_prop) {
                BUG_ON(pci_bus_count > map_prop->length);
                memcpy(map_prop->value, pci_to_OF_bus_map, pci_bus_count);
        }
        of_node_put(dn);
#ifdef DEBUG
        printk("PCI->OF bus map:\n");
        for (i=0; i<pci_bus_count; i++) {
                if (pci_to_OF_bus_map[i] == 0xff)
                        continue;
                printk("%d -> %d\n", i, pci_to_OF_bus_map[i]);
        }
#endif
}

typedef int (*pci_OF_scan_iterator)(struct device_node* node, void* data);

static struct device_node*
scan_OF_pci_childs(struct device_node* node, pci_OF_scan_iterator filter, void* data)
{
        struct device_node* sub_node;

        for (; node != 0;node = node->sibling) {
                const unsigned int *class_code;
        
                if (filter(node, data))
                        return node;

                /* For PCI<->PCI bridges or CardBus bridges, we go down
                 * Note: some OFs create a parent node "multifunc-device" as
                 * a fake root for all functions of a multi-function device,
                 * we go down them as well.
                 */
                class_code = of_get_property(node, "class-code", NULL);
                if ((!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
                        (*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS)) &&
                        strcmp(node->name, "multifunc-device"))
                        continue;
                sub_node = scan_OF_pci_childs(node->child, filter, data);
                if (sub_node)
                        return sub_node;
        }
        return NULL;
}

static struct device_node *scan_OF_for_pci_dev(struct device_node *parent,
                                               unsigned int devfn)
{
        struct device_node *np = NULL;
        const u32 *reg;
        unsigned int psize;

        while ((np = of_get_next_child(parent, np)) != NULL) {
                reg = of_get_property(np, "reg", &psize);
                if (reg == NULL || psize < 4)
                        continue;
                if (((reg[0] >> 8) & 0xff) == devfn)
                        return np;
        }
        return NULL;
}


static struct device_node *scan_OF_for_pci_bus(struct pci_bus *bus)
{
        struct device_node *parent, *np;

        /* Are we a root bus ? */
        if (bus->self == NULL || bus->parent == NULL) {
                struct pci_controller *hose = pci_bus_to_host(bus);
                if (hose == NULL)
                        return NULL;
                return of_node_get(hose->dn);
        }

        /* not a root bus, we need to get our parent */
        parent = scan_OF_for_pci_bus(bus->parent);
        if (parent == NULL)
                return NULL;

        /* now iterate for children for a match */
        np = scan_OF_for_pci_dev(parent, bus->self->devfn);
        of_node_put(parent);

        return np;
}

/*
 * Scans the OF tree for a device node matching a PCI device
 */
struct device_node *
pci_busdev_to_OF_node(struct pci_bus *bus, int devfn)
{
        struct device_node *parent, *np;

        if (!have_of)
                return NULL;

        DBG("pci_busdev_to_OF_node(%d,0x%x)\n", bus->number, devfn);
        parent = scan_OF_for_pci_bus(bus);
        if (parent == NULL)
                return NULL;
        DBG(" parent is %s\n", parent ? parent->full_name : "<NULL>");
        np = scan_OF_for_pci_dev(parent, devfn);
        of_node_put(parent);
        DBG(" result is %s\n", np ? np->full_name : "<NULL>");

        /* XXX most callers don't release the returned node
         * mostly because ppc64 doesn't increase the refcount,
         * we need to fix that.
         */
        return np;
}
EXPORT_SYMBOL(pci_busdev_to_OF_node);

struct device_node*
pci_device_to_OF_node(struct pci_dev *dev)
{
        return pci_busdev_to_OF_node(dev->bus, dev->devfn);
}
EXPORT_SYMBOL(pci_device_to_OF_node);

static int
find_OF_pci_device_filter(struct device_node* node, void* data)
{
        return ((void *)node == data);
}

/*
 * Returns the PCI device matching a given OF node
 */
int
pci_device_from_OF_node(struct device_node* node, u8* bus, u8* devfn)
{
        const unsigned int *reg;
        struct pci_controller* hose;
        struct pci_dev* dev = NULL;
        
        if (!have_of)
                return -ENODEV;
        /* Make sure it's really a PCI device */
        hose = pci_find_hose_for_OF_device(node);
        if (!hose || !hose->dn)
                return -ENODEV;
        if (!scan_OF_pci_childs(hose->dn->child,
                        find_OF_pci_device_filter, (void *)node))
                return -ENODEV;
        reg = of_get_property(node, "reg", NULL);
        if (!reg)
                return -ENODEV;
        *bus = (reg[0] >> 16) & 0xff;
        *devfn = ((reg[0] >> 8) & 0xff);

        /* Ok, here we need some tweak. If we have already renumbered
         * all busses, we can't rely on the OF bus number any more.
         * the pci_to_OF_bus_map is not enough as several PCI busses
         * may match the same OF bus number.
         */
        if (!pci_to_OF_bus_map)
                return 0;

        for_each_pci_dev(dev)
                if (pci_to_OF_bus_map[dev->bus->number] == *bus &&
                                dev->devfn == *devfn) {
                        *bus = dev->bus->number;
                        pci_dev_put(dev);
                        return 0;
                }

        return -ENODEV;
}
EXPORT_SYMBOL(pci_device_from_OF_node);

/* We create the "pci-OF-bus-map" property now so it appears in the
 * /proc device tree
 */
void __init
pci_create_OF_bus_map(void)
{
        struct property* of_prop;
        struct device_node *dn;

        of_prop = (struct property*) alloc_bootmem(sizeof(struct property) + 256);
        if (!of_prop)
                return;
        dn = of_find_node_by_path("/");
        if (dn) {
                memset(of_prop, -1, sizeof(struct property) + 256);
                of_prop->name = "pci-OF-bus-map";
                of_prop->length = 256;
                of_prop->value = &of_prop[1];
                prom_add_property(dn, of_prop);
                of_node_put(dn);
        }
}

#else /* CONFIG_PPC_OF */
void pcibios_make_OF_bus_map(void)
{
}
#endif /* CONFIG_PPC_OF */

static int __init
pcibios_init(void)
{
        struct pci_controller *hose, *tmp;
        struct pci_bus *bus;
        int next_busno = 0;

        printk(KERN_INFO "PCI: Probing PCI hardware\n");

        /* Scan all of the recorded PCI controllers.  */
        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
                if (pci_assign_all_buses)
                        hose->first_busno = next_busno;
                hose->last_busno = 0xff;
                bus = pci_scan_bus_parented(hose->parent, hose->first_busno,
                                            hose->ops, hose);
                if (bus)
                        pci_bus_add_devices(bus);
                hose->last_busno = bus->subordinate;
                if (pci_assign_all_buses || next_busno <= hose->last_busno)
                        next_busno = hose->last_busno + pcibios_assign_bus_offset;
        }
        pci_bus_count = next_busno;

        /* OpenFirmware based machines need a map of OF bus
         * numbers vs. kernel bus numbers since we may have to
         * remap them.
         */
        if (pci_assign_all_buses && have_of)
                pcibios_make_OF_bus_map();

        /* Call machine dependent fixup */
        if (ppc_md.pcibios_fixup)
                ppc_md.pcibios_fixup();

        /* Allocate and assign resources */
        pcibios_allocate_bus_resources(&pci_root_buses);
        pcibios_allocate_resources(0);
        pcibios_allocate_resources(1);

        DBG("PCI: Assigning unassigned resouces...\n");
        pci_assign_unassigned_resources();

        /* Call machine dependent post-init code */
        if (ppc_md.pcibios_after_init)
                ppc_md.pcibios_after_init();

        return 0;
}

subsys_initcall(pcibios_init);

void pcibios_fixup_bus(struct pci_bus *bus)
{
        struct pci_controller *hose = (struct pci_controller *) bus->sysdata;
        unsigned long io_offset;
        struct resource *res;
        struct pci_dev *dev;
        int i;

        io_offset = (unsigned long)hose->io_base_virt - isa_io_base;
        if (bus->parent == NULL) {
                /* This is a host bridge - fill in its resources */
                hose->bus = bus;

                bus->resource[0] = res = &hose->io_resource;
                if (!res->flags) {
                        if (io_offset)
                                printk(KERN_ERR "I/O resource not set for host"
                                       " bridge %d\n", hose->global_number);
                        res->start = 0;
                        res->end = IO_SPACE_LIMIT;
                        res->flags = IORESOURCE_IO;
                }
                res->start = (res->start + io_offset) & 0xffffffffu;
                res->end = (res->end + io_offset) & 0xffffffffu;

                for (i = 0; i < 3; ++i) {
                        res = &hose->mem_resources[i];
                        if (!res->flags) {
                                if (i > 0)
                                        continue;
                                printk(KERN_ERR "Memory resource not set for "
                                       "host bridge %d\n", hose->global_number);
                                res->start = hose->pci_mem_offset;
                                res->end = ~0U;
                                res->flags = IORESOURCE_MEM;
                        }
                        bus->resource[i+1] = res;
                }
        } else {
                /* This is a subordinate bridge */
                pci_read_bridge_bases(bus);

                for (i = 0; i < 4; ++i) {
                        if ((res = bus->resource[i]) == NULL)
                                continue;
                        if (!res->flags || bus->self->transparent)
                                continue;
                        if (io_offset && (res->flags & IORESOURCE_IO)) {
                                res->start = (res->start + io_offset) &
                                        0xffffffffu;
                                res->end = (res->end + io_offset) &
                                        0xffffffffu;
                        } else if (hose->pci_mem_offset
                                   && (res->flags & IORESOURCE_MEM)) {
                                res->start += hose->pci_mem_offset;
                                res->end += hose->pci_mem_offset;
                        }
                }
        }

        /* Platform specific bus fixups */
        if (ppc_md.pcibios_fixup_bus)
                ppc_md.pcibios_fixup_bus(bus);

        /* Read default IRQs and fixup if necessary */
        list_for_each_entry(dev, &bus->devices, bus_list) {
                pci_read_irq_line(dev);
                if (ppc_md.pci_irq_fixup)
                        ppc_md.pci_irq_fixup(dev);
        }
}

/* the next one is stolen from the alpha port... */
void __init
pcibios_update_irq(struct pci_dev *dev, int irq)
{
        pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
        /* XXX FIXME - update OF device tree node interrupt property */
}

int pcibios_enable_device(struct pci_dev *dev, int mask)
{
        u16 cmd, old_cmd;
        int idx;
        struct resource *r;

        if (ppc_md.pcibios_enable_device_hook)
                if (ppc_md.pcibios_enable_device_hook(dev, 0))
                        return -EINVAL;
                
        pci_read_config_word(dev, PCI_COMMAND, &cmd);
        old_cmd = cmd;
        for (idx=0; idx<6; idx++) {
                r = &dev->resource[idx];
                if (r->flags & IORESOURCE_UNSET) {
                        printk(KERN_ERR "PCI: Device %s not available because of resource collisions\n", pci_name(dev));
                        return -EINVAL;
                }
                if (r->flags & IORESOURCE_IO)
                        cmd |= PCI_COMMAND_IO;
                if (r->flags & IORESOURCE_MEM)
                        cmd |= PCI_COMMAND_MEMORY;
        }
        if (cmd != old_cmd) {
                printk("PCI: Enabling device %s (%04x -> %04x)\n",
                       pci_name(dev), old_cmd, cmd);
                pci_write_config_word(dev, PCI_COMMAND, cmd);
        }
        return 0;
}

static struct pci_controller*
pci_bus_to_hose(int bus)
{
        struct pci_controller *hose, *tmp;

        list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
                if (bus >= hose->first_busno && bus <= hose->last_busno)
                        return hose;
        return NULL;
}

/* Provide information on locations of various I/O regions in physical
 * memory.  Do this on a per-card basis so that we choose the right
 * root bridge.
 * Note that the returned IO or memory base is a physical address
 */

long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn)
{
        struct pci_controller* hose;
        long result = -EOPNOTSUPP;

        /* Argh ! Please forgive me for that hack, but that's the
         * simplest way to get existing XFree to not lockup on some
         * G5 machines... So when something asks for bus 0 io base
         * (bus 0 is HT root), we return the AGP one instead.
         */
#ifdef CONFIG_PPC_PMAC
        if (machine_is(powermac) && machine_is_compatible("MacRISC4"))
                if (bus == 0)
                        bus = 0xf0;
#endif /* CONFIG_PPC_PMAC */

        hose = pci_bus_to_hose(bus);
        if (!hose)
                return -ENODEV;

        switch (which) {
        case IOBASE_BRIDGE_NUMBER:
                return (long)hose->first_busno;
        case IOBASE_MEMORY:
                return (long)hose->pci_mem_offset;
        case IOBASE_IO:
                return (long)hose->io_base_phys;
        case IOBASE_ISA_IO:
                return (long)isa_io_base;
        case IOBASE_ISA_MEM:
                return (long)isa_mem_base;
        }

        return result;
}

unsigned long pci_address_to_pio(phys_addr_t address)
{
        struct pci_controller *hose, *tmp;

        list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
                unsigned int size = hose->io_resource.end -
                        hose->io_resource.start + 1;
                if (address >= hose->io_base_phys &&
                    address < (hose->io_base_phys + size)) {
                        unsigned long base =
                                (unsigned long)hose->io_base_virt - _IO_BASE;
                        return base + (address - hose->io_base_phys);
                }
        }
        return (unsigned int)-1;
}
EXPORT_SYMBOL(pci_address_to_pio);

/*
 * Null PCI config access functions, for the case when we can't
 * find a hose.
 */
#define NULL_PCI_OP(rw, size, type)                                     \
static int                                                              \
null_##rw##_config_##size(struct pci_dev *dev, int offset, type val)    \
{                                                                       \
        return PCIBIOS_DEVICE_NOT_FOUND;                                \
}

static int
null_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
                 int len, u32 *val)
{
        return PCIBIOS_DEVICE_NOT_FOUND;
}

static int
null_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
                  int len, u32 val)
{
        return PCIBIOS_DEVICE_NOT_FOUND;
}

static struct pci_ops null_pci_ops =
{
        .read = null_read_config,
        .write = null_write_config,
};

/*
 * These functions are used early on before PCI scanning is done
 * and all of the pci_dev and pci_bus structures have been created.
 */
static struct pci_bus *
fake_pci_bus(struct pci_controller *hose, int busnr)
{
        static struct pci_bus bus;

        if (hose == 0) {
                hose = pci_bus_to_hose(busnr);
                if (hose == 0)
                        printk(KERN_ERR "Can't find hose for PCI bus %d!\n", busnr);
        }
        bus.number = busnr;
        bus.sysdata = hose;
        bus.ops = hose? hose->ops: &null_pci_ops;
        return &bus;
}

#define EARLY_PCI_OP(rw, size, type)                                    \
int early_##rw##_config_##size(struct pci_controller *hose, int bus,    \
                               int devfn, int offset, type value)       \
{                                                                       \
        return pci_bus_##rw##_config_##size(fake_pci_bus(hose, bus),    \
                                            devfn, offset, value);      \
}

EARLY_PCI_OP(read, byte, u8 *)
EARLY_PCI_OP(read, word, u16 *)
EARLY_PCI_OP(read, dword, u32 *)
EARLY_PCI_OP(write, byte, u8)
EARLY_PCI_OP(write, word, u16)
EARLY_PCI_OP(write, dword, u32)

extern int pci_bus_find_capability (struct pci_bus *bus, unsigned int devfn, int cap);
int early_find_capability(struct pci_controller *hose, int bus, int devfn,
                          int cap)
{
        return pci_bus_find_capability(fake_pci_bus(hose, bus), devfn, cap);
}