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[hh.org.git] / arch / ppc / kernel / pci.c

/*
 * Common 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 <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/irq.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 isa_mem_base    = 0;
unsigned long pci_dram_offset = 0;
int pcibios_assign_bus_offset = 1;

void pcibios_make_OF_bus_map(void);

static int pci_relocate_bridge_resource(struct pci_bus *bus, int i);
static int probe_resource(struct pci_bus *parent, struct resource *pr,
                          struct resource *res, struct resource **conflict);
static void update_bridge_base(struct pci_bus *bus, int i);
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);

/* By default, we don't re-assign bus numbers.
 */
int pci_assign_all_buses;

struct pci_controller* hose_head;
struct pci_controller** hose_tail = &hose_head;

static int pci_bus_count;

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;
        unsigned long offset;

        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,
                                (unsigned long long)res->start,
                                (unsigned long long)res->end);
                        res->end -= res->start;
                        res->start = 0;
                        res->flags |= IORESOURCE_UNSET;
                        continue;
                }
                offset = 0;
                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;
                }
                if (offset != 0) {
                        res->start += offset;
                        res->end += offset;
#ifdef DEBUG
                        printk("Fixup res %d (%lx) of dev %s: %lx -> %lx\n",
                               i, res->flags, pci_name(dev),
                               res->start - offset, res->start);
#endif
                }
        }

        /* 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)
{
        unsigned long offset = 0;
        struct pci_controller *hose = dev->sysdata;

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

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

        if (hose && res->flags & IORESOURCE_IO)
                offset = (unsigned long)hose->io_base_virt - isa_io_base;
        else if (hose && res->flags & IORESOURCE_MEM)
                offset = hose->pci_mem_offset;
        res->start = region->start + offset;
        res->end = region->end + offset;
}
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 (size > 0x100) {
                        printk(KERN_ERR "PCI: I/O Region %s/%d too large"
                               " (%lld bytes)\n", pci_name(dev),
                               dev->resource - res, (unsigned long long)size);
                }

                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: bridge rsrc %llx..%llx (%lx), parent %p\n",
                                (unsigned long long)res->start,
                                (unsigned long long)res->end, res->flags, pr);
                        if (pr) {
                                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_ERR "PCI: Cannot allocate resource region "
                               "%d of PCI bridge %d\n", i, bus->number);
                        if (pci_relocate_bridge_resource(bus, i))
                                bus->resource[i] = NULL;
                }
                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, (unsigned long long)p->start,
                        (unsigned long long)p->end, res->name);
        }
        return 0;
}

/*
 * A bridge has been allocated a range which is outside the range
 * of its parent bridge, so it needs to be moved.
 */
static int __init
pci_relocate_bridge_resource(struct pci_bus *bus, int i)
{
        struct resource *res, *pr, *conflict;
        unsigned long try, size;
        int j;
        struct pci_bus *parent = bus->parent;

        if (parent == NULL) {
                /* shouldn't ever happen */
                printk(KERN_ERR "PCI: can't move host bridge resource\n");
                return -1;
        }
        res = bus->resource[i];
        if (res == NULL)
                return -1;
        pr = NULL;
        for (j = 0; j < 4; j++) {
                struct resource *r = parent->resource[j];
                if (!r)
                        continue;
                if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
                        continue;
                if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH)) {
                        pr = r;
                        break;
                }
                if (res->flags & IORESOURCE_PREFETCH)
                        pr = r;
        }
        if (pr == NULL)
                return -1;
        size = res->end - res->start;
        if (pr->start > pr->end || size > pr->end - pr->start)
                return -1;
        try = pr->end;
        for (;;) {
                res->start = try - size;
                res->end = try;
                if (probe_resource(bus->parent, pr, res, &conflict) == 0)
                        break;
                if (conflict->start <= pr->start + size)
                        return -1;
                try = conflict->start - 1;
        }
        if (request_resource(pr, res)) {
                DBG(KERN_ERR "PCI: huh? couldn't move to %llx..%llx\n",
                        (unsigned long long)res->start,
                        (unsigned long long)res->end);
                return -1;              /* "can't happen" */
        }
        update_bridge_base(bus, i);
        printk(KERN_INFO "PCI: bridge %d resource %d moved to %llx..%llx\n",
                bus->number, i, (unsigned long long)res->start,
                (unsigned long long)res->end);
        return 0;
}

static int __init
probe_resource(struct pci_bus *parent, struct resource *pr,
               struct resource *res, struct resource **conflict)
{
        struct pci_bus *bus;
        struct pci_dev *dev;
        struct resource *r;
        int i;

        for (r = pr->child; r != NULL; r = r->sibling) {
                if (r->end >= res->start && res->end >= r->start) {
                        *conflict = r;
                        return 1;
                }
        }
        list_for_each_entry(bus, &parent->children, node) {
                for (i = 0; i < 4; ++i) {
                        if ((r = bus->resource[i]) == NULL)
                                continue;
                        if (!r->flags || r->start > r->end || r == res)
                                continue;
                        if (pci_find_parent_resource(bus->self, r) != pr)
                                continue;
                        if (r->end >= res->start && res->end >= r->start) {
                                *conflict = r;
                                return 1;
                        }
                }
        }
        list_for_each_entry(dev, &parent->devices, bus_list) {
                for (i = 0; i < 6; ++i) {
                        r = &dev->resource[i];
                        if (!r->flags || (r->flags & IORESOURCE_UNSET))
                                continue;
                        if (pci_find_parent_resource(dev, r) != pr)
                                continue;
                        if (r->end >= res->start && res->end >= r->start) {
                                *conflict = r;
                                return 1;
                        }
                }
        }
        return 0;
}

static void __init
update_bridge_base(struct pci_bus *bus, int i)
{
        struct resource *res = bus->resource[i];
        u8 io_base_lo, io_limit_lo;
        u16 mem_base, mem_limit;
        u16 cmd;
        unsigned long start, end, off;
        struct pci_dev *dev = bus->self;
        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) {
                        pci_write_config_word(dev, PCI_IO_BASE_UPPER16,
                                              start >> 16);
                        pci_write_config_word(dev, PCI_IO_LIMIT_UPPER16,
                                              end >> 16);
                        io_base_lo |= PCI_IO_RANGE_TYPE_32;
                } else
                        io_base_lo |= PCI_IO_RANGE_TYPE_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 %d has flags=%lx\n",
                    pci_name(dev), i, 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:%s: Resource %d: %016llx-%016llx (f=%lx)\n",
            pci_name(dev), idx, (unsigned long long)r->start,
            (unsigned long long)r->end, r->flags);
        pr = pci_find_parent_resource(dev, r);
        if (!pr || request_resource(pr, r) < 0) {
                printk(KERN_ERR "PCI: Cannot allocate resource region %d"
                       " of device %s\n", idx, pci_name(dev));
                if (pr)
                        DBG("PCI:  parent is %p: %016llx-%016llx (f=%lx)\n",
                                pr, (unsigned long long)pr->start,
                                (unsigned long long)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);
                }
        }
}

static void __init
pcibios_assign_resources(void)
{
        struct pci_dev *dev = NULL;
        int idx;
        struct resource *r;

        for_each_pci_dev(dev) {
                int class = dev->class >> 8;

                /* Don't touch classless devices and host bridges */
                if (!class || class == PCI_CLASS_BRIDGE_HOST)
                        continue;

                for (idx = 0; idx < 6; idx++) {
                        r = &dev->resource[idx];

                        /*
                         * We shall assign a new address to this resource,
                         * either because the BIOS (sic) forgot to do so
                         * or because we have decided the old address was
                         * unusable for some reason.
                         */
                        if ((r->flags & IORESOURCE_UNSET) && r->end &&
                            (!ppc_md.pcibios_enable_device_hook ||
                             !ppc_md.pcibios_enable_device_hook(dev, 1))) {
                                r->flags &= ~IORESOURCE_UNSET;
                                pci_assign_resource(dev, idx);
                        }
                }

#if 0 /* don't assign ROMs */
                r = &dev->resource[PCI_ROM_RESOURCE];
                r->end -= r->start;
                r->start = 0;
                if (r->end)
                        pci_assign_resource(dev, PCI_ROM_RESOURCE);
#endif
        }
}


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

        pci_read_config_word(dev, PCI_COMMAND, &cmd);
        old_cmd = cmd;
        for (idx=0; idx<6; idx++) {
                /* Only set up the requested stuff */
                if (!(mask & (1<<idx)))
                        continue;
        
                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 (dev->resource[PCI_ROM_RESOURCE].start)
                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 int next_controller_index;

struct pci_controller * __init
pcibios_alloc_controller(void)
{
        struct pci_controller *hose;

        hose = (struct pci_controller *)alloc_bootmem(sizeof(*hose));
        memset(hose, 0, sizeof(struct pci_controller));

        *hose_tail = hose;
        hose_tail = &hose->next;

        hose->index = next_controller_index++;

        return hose;
}

void pcibios_make_OF_bus_map(void)
{
}

/* Add sysfs properties */
void pcibios_add_platform_entries(struct pci_dev *pdev)
{
}


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

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

        /* Scan all of the recorded PCI controllers.  */
        for (next_busno = 0, hose = hose_head; hose; hose = hose->next) {
                if (pci_assign_all_buses)
                        hose->first_busno = next_busno;
                hose->last_busno = 0xff;
                bus = pci_scan_bus(hose->first_busno, hose->ops, hose);
                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();

        /* Do machine dependent PCI interrupt routing */
        if (ppc_md.pci_swizzle && ppc_md.pci_map_irq)
                pci_fixup_irqs(ppc_md.pci_swizzle, ppc_md.pci_map_irq);

        /* 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);
        pcibios_assign_resources();

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

        return 0;
}

subsys_initcall(pcibios_init);

unsigned char __init
common_swizzle(struct pci_dev *dev, unsigned char *pinp)
{
        struct pci_controller *hose = dev->sysdata;

        if (dev->bus->number != hose->first_busno) {
                u8 pin = *pinp;
                do {
                        pin = bridge_swizzle(pin, PCI_SLOT(dev->devfn));
                        /* Move up the chain of bridges. */
                        dev = dev->bus->self;
                } while (dev->bus->self);
                *pinp = pin;

                /* The slot is the idsel of the last bridge. */
        }
        return PCI_SLOT(dev->devfn);
}

unsigned long resource_fixup(struct pci_dev * dev, struct resource * res,
                             unsigned long start, unsigned long size)
{
        return start;
}

void __init pcibios_fixup_bus(struct pci_bus *bus)
{
        struct pci_controller *hose = (struct pci_controller *) bus->sysdata;
        unsigned long io_offset;
        struct resource *res;
        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->index);
                        res->start = 0;
                        res->end = IO_SPACE_LIMIT;
                        res->flags = IORESOURCE_IO;
                }
                res->start += io_offset;
                res->end += io_offset;

                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->index);
                                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)
                                continue;
                        if (io_offset && (res->flags & IORESOURCE_IO)) {
                                res->start += io_offset;
                                res->end += io_offset;
                        } else if (hose->pci_mem_offset
                                   && (res->flags & IORESOURCE_MEM)) {
                                res->start += hose->pci_mem_offset;
                                res->end += hose->pci_mem_offset;
                        }
                }
        }

        if (ppc_md.pcibios_fixup_bus)
                ppc_md.pcibios_fixup_bus(bus);
}

char __init *pcibios_setup(char *str)
{
        return str;
}

/* 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;
}

struct pci_controller*
pci_bus_to_hose(int bus)
{
        struct pci_controller* hose = hose_head;

        for (; hose; hose = hose->next)
                if (bus >= hose->first_busno && bus <= hose->last_busno)
                        return hose;
        return NULL;
}

void __iomem *
pci_bus_io_base(unsigned int bus)
{
        struct pci_controller *hose;

        hose = pci_bus_to_hose(bus);
        if (!hose)
                return NULL;
        return hose->io_base_virt;
}

unsigned long
pci_bus_io_base_phys(unsigned int bus)
{
        struct pci_controller *hose;

        hose = pci_bus_to_hose(bus);
        if (!hose)
                return 0;
        return hose->io_base_phys;
}

unsigned long
pci_bus_mem_base_phys(unsigned int bus)
{
        struct pci_controller *hose;

        hose = pci_bus_to_hose(bus);
        if (!hose)
                return 0;
        return hose->pci_mem_offset;
}

unsigned long
pci_resource_to_bus(struct pci_dev *pdev, struct resource *res)
{
        /* Hack alert again ! See comments in chrp_pci.c
         */
        struct pci_controller* hose =
                (struct pci_controller *)pdev->sysdata;
        if (hose && res->flags & IORESOURCE_MEM)
                return res->start - hose->pci_mem_offset;
        /* We may want to do something with IOs here... */
        return res->start;
}


static struct resource *__pci_mmap_make_offset(struct pci_dev *dev,
                                               unsigned long *offset,
                                               enum pci_mmap_state mmap_state)
{
        struct pci_controller *hose = pci_bus_to_hose(dev->bus->number);
        unsigned long io_offset = 0;
        int i, res_bit;

        if (hose == 0)
                return NULL;            /* should never happen */

        /* If memory, add on the PCI bridge address offset */
        if (mmap_state == pci_mmap_mem) {
                *offset += hose->pci_mem_offset;
                res_bit = IORESOURCE_MEM;
        } else {
                io_offset = hose->io_base_virt - ___IO_BASE;
                *offset += io_offset;
                res_bit = IORESOURCE_IO;
        }

        /*
         * Check that the offset requested corresponds to one of the
         * resources of the device.
         */
        for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
                struct resource *rp = &dev->resource[i];
                int flags = rp->flags;

                /* treat ROM as memory (should be already) */
                if (i == PCI_ROM_RESOURCE)
                        flags |= IORESOURCE_MEM;

                /* Active and same type? */
                if ((flags & res_bit) == 0)
                        continue;

                /* In the range of this resource? */
                if (*offset < (rp->start & PAGE_MASK) || *offset > rp->end)
                        continue;

                /* found it! construct the final physical address */
                if (mmap_state == pci_mmap_io)
                        *offset += hose->io_base_phys - io_offset;
                return rp;
        }

        return NULL;
}

/*
 * Set vm_page_prot of VMA, as appropriate for this architecture, for a pci
 * device mapping.
 */
static pgprot_t __pci_mmap_set_pgprot(struct pci_dev *dev, struct resource *rp,
                                      pgprot_t protection,
                                      enum pci_mmap_state mmap_state,
                                      int write_combine)
{
        unsigned long prot = pgprot_val(protection);

        /* Write combine is always 0 on non-memory space mappings. On
         * memory space, if the user didn't pass 1, we check for a
         * "prefetchable" resource. This is a bit hackish, but we use
         * this to workaround the inability of /sysfs to provide a write
         * combine bit
         */
        if (mmap_state != pci_mmap_mem)
                write_combine = 0;
        else if (write_combine == 0) {
                if (rp->flags & IORESOURCE_PREFETCH)
                        write_combine = 1;
        }

        /* XXX would be nice to have a way to ask for write-through */
        prot |= _PAGE_NO_CACHE;
        if (write_combine)
                prot &= ~_PAGE_GUARDED;
        else
                prot |= _PAGE_GUARDED;

        printk("PCI map for %s:%llx, prot: %lx\n", pci_name(dev),
                (unsigned long long)rp->start, prot);

        return __pgprot(prot);
}

/*
 * This one is used by /dev/mem and fbdev who have no clue about the
 * PCI device, it tries to find the PCI device first and calls the
 * above routine
 */
pgprot_t pci_phys_mem_access_prot(struct file *file,
                                  unsigned long pfn,
                                  unsigned long size,
                                  pgprot_t protection)
{
        struct pci_dev *pdev = NULL;
        struct resource *found = NULL;
        unsigned long prot = pgprot_val(protection);
        unsigned long offset = pfn << PAGE_SHIFT;
        int i;

        if (page_is_ram(pfn))
                return prot;

        prot |= _PAGE_NO_CACHE | _PAGE_GUARDED;

        for_each_pci_dev(pdev) {
                for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
                        struct resource *rp = &pdev->resource[i];
                        int flags = rp->flags;

                        /* Active and same type? */
                        if ((flags & IORESOURCE_MEM) == 0)
                                continue;
                        /* In the range of this resource? */
                        if (offset < (rp->start & PAGE_MASK) ||
                            offset > rp->end)
                                continue;
                        found = rp;
                        break;
                }
                if (found)
                        break;
        }
        if (found) {
                if (found->flags & IORESOURCE_PREFETCH)
                        prot &= ~_PAGE_GUARDED;
                pci_dev_put(pdev);
        }

        DBG("non-PCI map for %lx, prot: %lx\n", offset, prot);

        return __pgprot(prot);
}


/*
 * Perform the actual remap of the pages for a PCI device mapping, as
 * appropriate for this architecture.  The region in the process to map
 * is described by vm_start and vm_end members of VMA, the base physical
 * address is found in vm_pgoff.
 * The pci device structure is provided so that architectures may make mapping
 * decisions on a per-device or per-bus basis.
 *
 * Returns a negative error code on failure, zero on success.
 */
int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
                        enum pci_mmap_state mmap_state,
                        int write_combine)
{
        unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
        struct resource *rp;
        int ret;

        rp = __pci_mmap_make_offset(dev, &offset, mmap_state);
        if (rp == NULL)
                return -EINVAL;

        vma->vm_pgoff = offset >> PAGE_SHIFT;
        vma->vm_page_prot = __pci_mmap_set_pgprot(dev, rp,
                                                  vma->vm_page_prot,
                                                  mmap_state, write_combine);

        ret = remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
                               vma->vm_end - vma->vm_start, vma->vm_page_prot);

        return ret;
}

/* Obsolete functions. Should be removed once the symbios driver
 * is fixed
 */
unsigned long
phys_to_bus(unsigned long pa)
{
        struct pci_controller *hose;
        int i;

        for (hose = hose_head; hose; hose = hose->next) {
                for (i = 0; i < 3; ++i) {
                        if (pa >= hose->mem_resources[i].start
                            && pa <= hose->mem_resources[i].end) {
                                /*
                                 * XXX the hose->pci_mem_offset really
                                 * only applies to mem_resources[0].
                                 * We need a way to store an offset for
                                 * the others.  -- paulus
                                 */
                                if (i == 0)
                                        pa -= hose->pci_mem_offset;
                                return pa;
                        }
                }
        }
        /* hmmm, didn't find it */
        return 0;
}

unsigned long
pci_phys_to_bus(unsigned long pa, int busnr)
{
        struct pci_controller* hose = pci_bus_to_hose(busnr);
        if (!hose)
                return pa;
        return pa - hose->pci_mem_offset;
}

unsigned long
pci_bus_to_phys(unsigned int ba, int busnr)
{
        struct pci_controller* hose = pci_bus_to_hose(busnr);
        if (!hose)
                return ba;
        return ba + hose->pci_mem_offset;
}

/* 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;

        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;
}

void pci_resource_to_user(const struct pci_dev *dev, int bar,
                          const struct resource *rsrc,
                          resource_size_t *start, resource_size_t *end)
{
        struct pci_controller *hose = pci_bus_to_hose(dev->bus->number);
        unsigned long offset = 0;

        if (hose == NULL)
                return;

        if (rsrc->flags & IORESOURCE_IO)
                offset = ___IO_BASE - hose->io_base_virt + hose->io_base_phys;

        *start = rsrc->start + offset;
        *end = rsrc->end + offset;
}

void __init
pci_init_resource(struct resource *res, unsigned long start, unsigned long end,
                  int flags, char *name)
{
        res->start = start;
        res->end = end;
        res->flags = flags;
        res->name = name;
        res->parent = NULL;
        res->sibling = NULL;
        res->child = NULL;
}

void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max)
{
        unsigned long start = pci_resource_start(dev, bar);
        unsigned long len = pci_resource_len(dev, bar);
        unsigned long flags = pci_resource_flags(dev, bar);

        if (!len)
                return NULL;
        if (max && len > max)
                len = max;
        if (flags & IORESOURCE_IO)
                return ioport_map(start, len);
        if (flags & IORESOURCE_MEM)
                /* Not checking IORESOURCE_CACHEABLE because PPC does
                 * not currently distinguish between ioremap and
                 * ioremap_nocache.
                 */
                return ioremap(start, len);
        /* What? */
        return NULL;
}

void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
{
        /* Nothing to do */
}
EXPORT_SYMBOL(pci_iomap);
EXPORT_SYMBOL(pci_iounmap);

unsigned long pci_address_to_pio(phys_addr_t address)
{
        struct pci_controller* hose = hose_head;

        for (; hose; hose = hose->next) {
                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 =
{
        null_read_config,
        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)