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;

/* Default PCI flags is 0 */
unsigned int ppc_pci_flags;

void pcibios_make_OF_bus_map(void);

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
 */
static 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 int skip_isa_ioresource_align(struct pci_dev *dev)
{
	if ((ppc_pci_flags & PPC_PCI_CAN_SKIP_ISA_ALIGN) &&
	    !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA))
		return 1;
	return 0;
}

/*
 * 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 (skip_isa_ioresource_align(dev))
			return;
		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 {
				/* Don't bother with non-root busses when
				 * re-assigning all resources.
				 */
				if (ppc_pci_flags & PPC_PCI_REASSIGN_ALL_RSRC)
					continue;
				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");

	if (ppc_pci_flags & PPC_PCI_REASSIGN_ALL_BUS)
		pci_assign_all_buses = 1;

	/* 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. If we re-assign everything, then
	 * we skip the allocate phase
	 */
	pcibios_allocate_bus_resources(&pci_root_buses);
	if (!(ppc_pci_flags & PPC_PCI_REASSIGN_ALL_RSRC)) {
		pcibios_allocate_resources(0);
		pcibios_allocate_resources(1);
	}
	if (!(ppc_pci_flags & PPC_PCI_PROBE_ONLY)) {
		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 __devinit pcibios_do_bus_setup(struct pci_bus *bus)
{
	struct pci_controller *hose = (struct pci_controller *) bus->sysdata;
	unsigned long io_offset;
	struct resource *res;
	int i;

	/* Hookup PHB resources */
	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;
		}
	}
}

/* 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;

	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);
}