Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 1861 insertions, 0 deletions

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
new file mode 100644
index 00000000..5e1ca3c5
--- /dev/null
+++ b/drivers/pci/probe.c
@@ -0,0 +1,1861 @@
+/*
+ * probe.c - PCI detection and setup code
+ */
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/cpumask.h>
+#include <linux/pci-aspm.h>
+#include "pci.h"
+
+#define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */
+#define CARDBUS_RESERVE_BUSNR	3
+
+static LIST_HEAD(pci_host_bridges);
+
+/* Ugh.  Need to stop exporting this to modules. */
+LIST_HEAD(pci_root_buses);
+EXPORT_SYMBOL(pci_root_buses);
+
+
+static int find_anything(struct device *dev, void *data)
+{
+	return 1;
+}
+
+/*
+ * Some device drivers need know if pci is initiated.
+ * Basically, we think pci is not initiated when there
+ * is no device to be found on the pci_bus_type.
+ */
+int no_pci_devices(void)
+{
+	struct device *dev;
+	int no_devices;
+
+	dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
+	no_devices = (dev == NULL);
+	put_device(dev);
+	return no_devices;
+}
+EXPORT_SYMBOL(no_pci_devices);
+
+static struct pci_host_bridge *pci_host_bridge(struct pci_dev *dev)
+{
+	struct pci_bus *bus;
+	struct pci_host_bridge *bridge;
+
+	bus = dev->bus;
+	while (bus->parent)
+		bus = bus->parent;
+
+	list_for_each_entry(bridge, &pci_host_bridges, list) {
+		if (bridge->bus == bus)
+			return bridge;
+	}
+
+	return NULL;
+}
+
+static bool resource_contains(struct resource *res1, struct resource *res2)
+{
+	return res1->start <= res2->start && res1->end >= res2->end;
+}
+
+void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
+			     struct resource *res)
+{
+	struct pci_host_bridge *bridge = pci_host_bridge(dev);
+	struct pci_host_bridge_window *window;
+	resource_size_t offset = 0;
+
+	list_for_each_entry(window, &bridge->windows, list) {
+		if (resource_type(res) != resource_type(window->res))
+			continue;
+
+		if (resource_contains(window->res, res)) {
+			offset = window->offset;
+			break;
+		}
+	}
+
+	region->start = res->start - offset;
+	region->end = res->end - offset;
+}
+EXPORT_SYMBOL(pcibios_resource_to_bus);
+
+static bool region_contains(struct pci_bus_region *region1,
+			    struct pci_bus_region *region2)
+{
+	return region1->start <= region2->start && region1->end >= region2->end;
+}
+
+void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+			     struct pci_bus_region *region)
+{
+	struct pci_host_bridge *bridge = pci_host_bridge(dev);
+	struct pci_host_bridge_window *window;
+	struct pci_bus_region bus_region;
+	resource_size_t offset = 0;
+
+	list_for_each_entry(window, &bridge->windows, list) {
+		if (resource_type(res) != resource_type(window->res))
+			continue;
+
+		bus_region.start = window->res->start - window->offset;
+		bus_region.end = window->res->end - window->offset;
+
+		if (region_contains(&bus_region, region)) {
+			offset = window->offset;
+			break;
+		}
+	}
+
+	res->start = region->start + offset;
+	res->end = region->end + offset;
+}
+EXPORT_SYMBOL(pcibios_bus_to_resource);
+
+/*
+ * PCI Bus Class
+ */
+static void release_pcibus_dev(struct device *dev)
+{
+	struct pci_bus *pci_bus = to_pci_bus(dev);
+
+	if (pci_bus->bridge)
+		put_device(pci_bus->bridge);
+	pci_bus_remove_resources(pci_bus);
+	pci_release_bus_of_node(pci_bus);
+	kfree(pci_bus);
+}
+
+static struct class pcibus_class = {
+	.name		= "pci_bus",
+	.dev_release	= &release_pcibus_dev,
+	.dev_attrs	= pcibus_dev_attrs,
+};
+
+static int __init pcibus_class_init(void)
+{
+	return class_register(&pcibus_class);
+}
+postcore_initcall(pcibus_class_init);
+
+static u64 pci_size(u64 base, u64 maxbase, u64 mask)
+{
+	u64 size = mask & maxbase;	/* Find the significant bits */
+	if (!size)
+		return 0;
+
+	/* Get the lowest of them to find the decode size, and
+	   from that the extent.  */
+	size = (size & ~(size-1)) - 1;
+
+	/* base == maxbase can be valid only if the BAR has
+	   already been programmed with all 1s.  */
+	if (base == maxbase && ((base | size) & mask) != mask)
+		return 0;
+
+	return size;
+}
+
+static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
+{
+	u32 mem_type;
+	unsigned long flags;
+
+	if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
+		flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
+		flags |= IORESOURCE_IO;
+		return flags;
+	}
+
+	flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
+	flags |= IORESOURCE_MEM;
+	if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
+		flags |= IORESOURCE_PREFETCH;
+
+	mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
+	switch (mem_type) {
+	case PCI_BASE_ADDRESS_MEM_TYPE_32:
+		break;
+	case PCI_BASE_ADDRESS_MEM_TYPE_1M:
+		dev_info(&dev->dev, "1M mem BAR treated as 32-bit BAR\n");
+		break;
+	case PCI_BASE_ADDRESS_MEM_TYPE_64:
+		flags |= IORESOURCE_MEM_64;
+		break;
+	default:
+		dev_warn(&dev->dev,
+			 "mem unknown type %x treated as 32-bit BAR\n",
+			 mem_type);
+		break;
+	}
+	return flags;
+}
+
+/**
+ * pci_read_base - read a PCI BAR
+ * @dev: the PCI device
+ * @type: type of the BAR
+ * @res: resource buffer to be filled in
+ * @pos: BAR position in the config space
+ *
+ * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
+ */
+int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
+			struct resource *res, unsigned int pos)
+{
+	u32 l, sz, mask;
+	u16 orig_cmd;
+	struct pci_bus_region region;
+
+	mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
+
+	if (!dev->mmio_always_on) {
+		pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
+		pci_write_config_word(dev, PCI_COMMAND,
+			orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
+	}
+
+	res->name = pci_name(dev);
+
+	pci_read_config_dword(dev, pos, &l);
+	pci_write_config_dword(dev, pos, l | mask);
+	pci_read_config_dword(dev, pos, &sz);
+	pci_write_config_dword(dev, pos, l);
+
+	if (!dev->mmio_always_on)
+		pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
+
+	/*
+	 * All bits set in sz means the device isn't working properly.
+	 * If the BAR isn't implemented, all bits must be 0.  If it's a
+	 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
+	 * 1 must be clear.
+	 */
+	if (!sz || sz == 0xffffffff)
+		goto fail;
+
+	/*
+	 * I don't know how l can have all bits set.  Copied from old code.
+	 * Maybe it fixes a bug on some ancient platform.
+	 */
+	if (l == 0xffffffff)
+		l = 0;
+
+	if (type == pci_bar_unknown) {
+		res->flags = decode_bar(dev, l);
+		res->flags |= IORESOURCE_SIZEALIGN;
+		if (res->flags & IORESOURCE_IO) {
+			l &= PCI_BASE_ADDRESS_IO_MASK;
+			mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
+		} else {
+			l &= PCI_BASE_ADDRESS_MEM_MASK;
+			mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
+		}
+	} else {
+		res->flags |= (l & IORESOURCE_ROM_ENABLE);
+		l &= PCI_ROM_ADDRESS_MASK;
+		mask = (u32)PCI_ROM_ADDRESS_MASK;
+	}
+
+	if (res->flags & IORESOURCE_MEM_64) {
+		u64 l64 = l;
+		u64 sz64 = sz;
+		u64 mask64 = mask | (u64)~0 << 32;
+
+		pci_read_config_dword(dev, pos + 4, &l);
+		pci_write_config_dword(dev, pos + 4, ~0);
+		pci_read_config_dword(dev, pos + 4, &sz);
+		pci_write_config_dword(dev, pos + 4, l);
+
+		l64 |= ((u64)l << 32);
+		sz64 |= ((u64)sz << 32);
+
+		sz64 = pci_size(l64, sz64, mask64);
+
+		if (!sz64)
+			goto fail;
+
+		if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
+			dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n",
+				pos);
+			goto fail;
+		}
+
+		if ((sizeof(resource_size_t) < 8) && l) {
+			/* Address above 32-bit boundary; disable the BAR */
+			pci_write_config_dword(dev, pos, 0);
+			pci_write_config_dword(dev, pos + 4, 0);
+			region.start = 0;
+			region.end = sz64;
+			pcibios_bus_to_resource(dev, res, &region);
+		} else {
+			region.start = l64;
+			region.end = l64 + sz64;
+			pcibios_bus_to_resource(dev, res, &region);
+			dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n",
+				   pos, res);
+		}
+	} else {
+		sz = pci_size(l, sz, mask);
+
+		if (!sz)
+			goto fail;
+
+		region.start = l;
+		region.end = l + sz;
+		pcibios_bus_to_resource(dev, res, &region);
+
+		dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
+	}
+
+ out:
+	return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
+ fail:
+	res->flags = 0;
+	goto out;
+}
+
+static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
+{
+	unsigned int pos, reg;
+
+	for (pos = 0; pos < howmany; pos++) {
+		struct resource *res = &dev->resource[pos];
+		reg = PCI_BASE_ADDRESS_0 + (pos << 2);
+		pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
+	}
+
+	if (rom) {
+		struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
+		dev->rom_base_reg = rom;
+		res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
+				IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
+				IORESOURCE_SIZEALIGN;
+		__pci_read_base(dev, pci_bar_mem32, res, rom);
+	}
+}
+
+static void __devinit pci_read_bridge_io(struct pci_bus *child)
+{
+	struct pci_dev *dev = child->self;
+	u8 io_base_lo, io_limit_lo;
+	unsigned long base, limit;
+	struct pci_bus_region region;
+	struct resource *res, res2;
+
+	res = child->resource[0];
+	pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
+	pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
+	base = (io_base_lo & PCI_IO_RANGE_MASK) << 8;
+	limit = (io_limit_lo & PCI_IO_RANGE_MASK) << 8;
+
+	if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
+		u16 io_base_hi, io_limit_hi;
+		pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
+		pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
+		base |= (io_base_hi << 16);
+		limit |= (io_limit_hi << 16);
+	}
+
+	if (base && base <= limit) {
+		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
+		res2.flags = res->flags;
+		region.start = base;
+		region.end = limit + 0xfff;
+		pcibios_bus_to_resource(dev, &res2, &region);
+		if (!res->start)
+			res->start = res2.start;
+		if (!res->end)
+			res->end = res2.end;
+		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+	}
+}
+
+static void __devinit pci_read_bridge_mmio(struct pci_bus *child)
+{
+	struct pci_dev *dev = child->self;
+	u16 mem_base_lo, mem_limit_lo;
+	unsigned long base, limit;
+	struct pci_bus_region region;
+	struct resource *res;
+
+	res = child->resource[1];
+	pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
+	pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
+	base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
+	limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
+	if (base && base <= limit) {
+		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
+		region.start = base;
+		region.end = limit + 0xfffff;
+		pcibios_bus_to_resource(dev, res, &region);
+		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+	}
+}
+
+static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child)
+{
+	struct pci_dev *dev = child->self;
+	u16 mem_base_lo, mem_limit_lo;
+	unsigned long base, limit;
+	struct pci_bus_region region;
+	struct resource *res;
+
+	res = child->resource[2];
+	pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
+	pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
+	base = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
+	limit = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
+
+	if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
+		u32 mem_base_hi, mem_limit_hi;
+		pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
+		pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
+
+		/*
+		 * Some bridges set the base > limit by default, and some
+		 * (broken) BIOSes do not initialize them.  If we find
+		 * this, just assume they are not being used.
+		 */
+		if (mem_base_hi <= mem_limit_hi) {
+#if BITS_PER_LONG == 64
+			base |= ((long) mem_base_hi) << 32;
+			limit |= ((long) mem_limit_hi) << 32;
+#else
+			if (mem_base_hi || mem_limit_hi) {
+				dev_err(&dev->dev, "can't handle 64-bit "
+					"address space for bridge\n");
+				return;
+			}
+#endif
+		}
+	}
+	if (base && base <= limit) {
+		res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
+					 IORESOURCE_MEM | IORESOURCE_PREFETCH;
+		if (res->flags & PCI_PREF_RANGE_TYPE_64)
+			res->flags |= IORESOURCE_MEM_64;
+		region.start = base;
+		region.end = limit + 0xfffff;
+		pcibios_bus_to_resource(dev, res, &region);
+		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+	}
+}
+
+void __devinit pci_read_bridge_bases(struct pci_bus *child)
+{
+	struct pci_dev *dev = child->self;
+	struct resource *res;
+	int i;
+
+	if (pci_is_root_bus(child))	/* It's a host bus, nothing to read */
+		return;
+
+	dev_info(&dev->dev, "PCI bridge to [bus %02x-%02x]%s\n",
+		 child->secondary, child->subordinate,
+		 dev->transparent ? " (subtractive decode)" : "");
+
+	pci_bus_remove_resources(child);
+	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
+		child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
+
+	pci_read_bridge_io(child);
+	pci_read_bridge_mmio(child);
+	pci_read_bridge_mmio_pref(child);
+
+	if (dev->transparent) {
+		pci_bus_for_each_resource(child->parent, res, i) {
+			if (res) {
+				pci_bus_add_resource(child, res,
+						     PCI_SUBTRACTIVE_DECODE);
+				dev_printk(KERN_DEBUG, &dev->dev,
+					   "  bridge window %pR (subtractive decode)\n",
+					   res);
+			}
+		}
+	}
+}
+
+static struct pci_bus * pci_alloc_bus(void)
+{
+	struct pci_bus *b;
+
+	b = kzalloc(sizeof(*b), GFP_KERNEL);
+	if (b) {
+		INIT_LIST_HEAD(&b->node);
+		INIT_LIST_HEAD(&b->children);
+		INIT_LIST_HEAD(&b->devices);
+		INIT_LIST_HEAD(&b->slots);
+		INIT_LIST_HEAD(&b->resources);
+		b->max_bus_speed = PCI_SPEED_UNKNOWN;
+		b->cur_bus_speed = PCI_SPEED_UNKNOWN;
+	}
+	return b;
+}
+
+static unsigned char pcix_bus_speed[] = {
+	PCI_SPEED_UNKNOWN,		/* 0 */
+	PCI_SPEED_66MHz_PCIX,		/* 1 */
+	PCI_SPEED_100MHz_PCIX,		/* 2 */
+	PCI_SPEED_133MHz_PCIX,		/* 3 */
+	PCI_SPEED_UNKNOWN,		/* 4 */
+	PCI_SPEED_66MHz_PCIX_ECC,	/* 5 */
+	PCI_SPEED_100MHz_PCIX_ECC,	/* 6 */
+	PCI_SPEED_133MHz_PCIX_ECC,	/* 7 */
+	PCI_SPEED_UNKNOWN,		/* 8 */
+	PCI_SPEED_66MHz_PCIX_266,	/* 9 */
+	PCI_SPEED_100MHz_PCIX_266,	/* A */
+	PCI_SPEED_133MHz_PCIX_266,	/* B */
+	PCI_SPEED_UNKNOWN,		/* C */
+	PCI_SPEED_66MHz_PCIX_533,	/* D */
+	PCI_SPEED_100MHz_PCIX_533,	/* E */
+	PCI_SPEED_133MHz_PCIX_533	/* F */
+};
+
+static unsigned char pcie_link_speed[] = {
+	PCI_SPEED_UNKNOWN,		/* 0 */
+	PCIE_SPEED_2_5GT,		/* 1 */
+	PCIE_SPEED_5_0GT,		/* 2 */
+	PCIE_SPEED_8_0GT,		/* 3 */
+	PCI_SPEED_UNKNOWN,		/* 4 */
+	PCI_SPEED_UNKNOWN,		/* 5 */
+	PCI_SPEED_UNKNOWN,		/* 6 */
+	PCI_SPEED_UNKNOWN,		/* 7 */
+	PCI_SPEED_UNKNOWN,		/* 8 */
+	PCI_SPEED_UNKNOWN,		/* 9 */
+	PCI_SPEED_UNKNOWN,		/* A */
+	PCI_SPEED_UNKNOWN,		/* B */
+	PCI_SPEED_UNKNOWN,		/* C */
+	PCI_SPEED_UNKNOWN,		/* D */
+	PCI_SPEED_UNKNOWN,		/* E */
+	PCI_SPEED_UNKNOWN		/* F */
+};
+
+void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
+{
+	bus->cur_bus_speed = pcie_link_speed[linksta & 0xf];
+}
+EXPORT_SYMBOL_GPL(pcie_update_link_speed);
+
+static unsigned char agp_speeds[] = {
+	AGP_UNKNOWN,
+	AGP_1X,
+	AGP_2X,
+	AGP_4X,
+	AGP_8X
+};
+
+static enum pci_bus_speed agp_speed(int agp3, int agpstat)
+{
+	int index = 0;
+
+	if (agpstat & 4)
+		index = 3;
+	else if (agpstat & 2)
+		index = 2;
+	else if (agpstat & 1)
+		index = 1;
+	else
+		goto out;
+	
+	if (agp3) {
+		index += 2;
+		if (index == 5)
+			index = 0;
+	}
+
+ out:
+	return agp_speeds[index];
+}
+
+
+static void pci_set_bus_speed(struct pci_bus *bus)
+{
+	struct pci_dev *bridge = bus->self;
+	int pos;
+
+	pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
+	if (!pos)
+		pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
+	if (pos) {
+		u32 agpstat, agpcmd;
+
+		pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
+		bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
+
+		pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
+		bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
+	}
+
+	pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
+	if (pos) {
+		u16 status;
+		enum pci_bus_speed max;
+		pci_read_config_word(bridge, pos + 2, &status);
+
+		if (status & 0x8000) {
+			max = PCI_SPEED_133MHz_PCIX_533;
+		} else if (status & 0x4000) {
+			max = PCI_SPEED_133MHz_PCIX_266;
+		} else if (status & 0x0002) {
+			if (((status >> 12) & 0x3) == 2) {
+				max = PCI_SPEED_133MHz_PCIX_ECC;
+			} else {
+				max = PCI_SPEED_133MHz_PCIX;
+			}
+		} else {
+			max = PCI_SPEED_66MHz_PCIX;
+		}
+
+		bus->max_bus_speed = max;
+		bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
+
+		return;
+	}
+
+	pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
+	if (pos) {
+		u32 linkcap;
+		u16 linksta;
+
+		pci_read_config_dword(bridge, pos + PCI_EXP_LNKCAP, &linkcap);
+		bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
+
+		pci_read_config_word(bridge, pos + PCI_EXP_LNKSTA, &linksta);
+		pcie_update_link_speed(bus, linksta);
+	}
+}
+
+
+static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
+					   struct pci_dev *bridge, int busnr)
+{
+	struct pci_bus *child;
+	int i;
+
+	/*
+	 * Allocate a new bus, and inherit stuff from the parent..
+	 */
+	child = pci_alloc_bus();
+	if (!child)
+		return NULL;
+
+	child->parent = parent;
+	child->ops = parent->ops;
+	child->sysdata = parent->sysdata;
+	child->bus_flags = parent->bus_flags;
+
+	/* initialize some portions of the bus device, but don't register it
+	 * now as the parent is not properly set up yet.  This device will get
+	 * registered later in pci_bus_add_devices()
+	 */
+	child->dev.class = &pcibus_class;
+	dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
+
+	/*
+	 * Set up the primary, secondary and subordinate
+	 * bus numbers.
+	 */
+	child->number = child->secondary = busnr;
+	child->primary = parent->secondary;
+	child->subordinate = 0xff;
+
+	if (!bridge)
+		return child;
+
+	child->self = bridge;
+	child->bridge = get_device(&bridge->dev);
+	pci_set_bus_of_node(child);
+	pci_set_bus_speed(child);
+
+	/* Set up default resource pointers and names.. */
+	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
+		child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
+		child->resource[i]->name = child->name;
+	}
+	bridge->subordinate = child;
+
+	return child;
+}
+
+struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
+{
+	struct pci_bus *child;
+
+	child = pci_alloc_child_bus(parent, dev, busnr);
+	if (child) {
+		down_write(&pci_bus_sem);
+		list_add_tail(&child->node, &parent->children);
+		up_write(&pci_bus_sem);
+	}
+	return child;
+}
+
+static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
+{
+	struct pci_bus *parent = child->parent;
+
+	/* Attempts to fix that up are really dangerous unless
+	   we're going to re-assign all bus numbers. */
+	if (!pcibios_assign_all_busses())
+		return;
+
+	while (parent->parent && parent->subordinate < max) {
+		parent->subordinate = max;
+		pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
+		parent = parent->parent;
+	}
+}
+
+/*
+ * If it's a bridge, configure it and scan the bus behind it.
+ * For CardBus bridges, we don't scan behind as the devices will
+ * be handled by the bridge driver itself.
+ *
+ * We need to process bridges in two passes -- first we scan those
+ * already configured by the BIOS and after we are done with all of
+ * them, we proceed to assigning numbers to the remaining buses in
+ * order to avoid overlaps between old and new bus numbers.
+ */
+int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
+{
+	struct pci_bus *child;
+	int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
+	u32 buses, i, j = 0;
+	u16 bctl;
+	u8 primary, secondary, subordinate;
+	int broken = 0;
+
+	pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
+	primary = buses & 0xFF;
+	secondary = (buses >> 8) & 0xFF;
+	subordinate = (buses >> 16) & 0xFF;
+
+	dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
+		secondary, subordinate, pass);
+
+	if (!primary && (primary != bus->number) && secondary && subordinate) {
+		dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
+		primary = bus->number;
+	}
+
+	/* Check if setup is sensible at all */
+	if (!pass &&
+	    (primary != bus->number || secondary <= bus->number)) {
+		dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
+		broken = 1;
+	}
+
+	/* Disable MasterAbortMode during probing to avoid reporting
+	   of bus errors (in some architectures) */ 
+	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
+	pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
+			      bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
+
+	if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
+	    !is_cardbus && !broken) {
+		unsigned int cmax;
+		/*
+		 * Bus already configured by firmware, process it in the first
+		 * pass and just note the configuration.
+		 */
+		if (pass)
+			goto out;
+
+		/*
+		 * If we already got to this bus through a different bridge,
+		 * don't re-add it. This can happen with the i450NX chipset.
+		 *
+		 * However, we continue to descend down the hierarchy and
+		 * scan remaining child buses.
+		 */
+		child = pci_find_bus(pci_domain_nr(bus), secondary);
+		if (!child) {
+			child = pci_add_new_bus(bus, dev, secondary);
+			if (!child)
+				goto out;
+			child->primary = primary;
+			child->subordinate = subordinate;
+			child->bridge_ctl = bctl;
+		}
+
+		cmax = pci_scan_child_bus(child);
+		if (cmax > max)
+			max = cmax;
+		if (child->subordinate > max)
+			max = child->subordinate;
+	} else {
+		/*
+		 * We need to assign a number to this bus which we always
+		 * do in the second pass.
+		 */
+		if (!pass) {
+			if (pcibios_assign_all_busses() || broken)
+				/* Temporarily disable forwarding of the
+				   configuration cycles on all bridges in
+				   this bus segment to avoid possible
+				   conflicts in the second pass between two
+				   bridges programmed with overlapping
+				   bus ranges. */
+				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
+						       buses & ~0xffffff);
+			goto out;
+		}
+
+		/* Clear errors */
+		pci_write_config_word(dev, PCI_STATUS, 0xffff);
+
+		/* Prevent assigning a bus number that already exists.
+		 * This can happen when a bridge is hot-plugged, so in
+		 * this case we only re-scan this bus. */
+		child = pci_find_bus(pci_domain_nr(bus), max+1);
+		if (!child) {
+			child = pci_add_new_bus(bus, dev, ++max);
+			if (!child)
+				goto out;
+		}
+		buses = (buses & 0xff000000)
+		      | ((unsigned int)(child->primary)     <<  0)
+		      | ((unsigned int)(child->secondary)   <<  8)
+		      | ((unsigned int)(child->subordinate) << 16);
+
+		/*
+		 * yenta.c forces a secondary latency timer of 176.
+		 * Copy that behaviour here.
+		 */
+		if (is_cardbus) {
+			buses &= ~0xff000000;
+			buses |= CARDBUS_LATENCY_TIMER << 24;
+		}
+
+		/*
+		 * We need to blast all three values with a single write.
+		 */
+		pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
+
+		if (!is_cardbus) {
+			child->bridge_ctl = bctl;
+			/*
+			 * Adjust subordinate busnr in parent buses.
+			 * We do this before scanning for children because
+			 * some devices may not be detected if the bios
+			 * was lazy.
+			 */
+			pci_fixup_parent_subordinate_busnr(child, max);
+			/* Now we can scan all subordinate buses... */
+			max = pci_scan_child_bus(child);
+			/*
+			 * now fix it up again since we have found
+			 * the real value of max.
+			 */
+			pci_fixup_parent_subordinate_busnr(child, max);
+		} else {
+			/*
+			 * For CardBus bridges, we leave 4 bus numbers
+			 * as cards with a PCI-to-PCI bridge can be
+			 * inserted later.
+			 */
+			for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
+				struct pci_bus *parent = bus;
+				if (pci_find_bus(pci_domain_nr(bus),
+							max+i+1))
+					break;
+				while (parent->parent) {
+					if ((!pcibios_assign_all_busses()) &&
+					    (parent->subordinate > max) &&
+					    (parent->subordinate <= max+i)) {
+						j = 1;
+					}
+					parent = parent->parent;
+				}
+				if (j) {
+					/*
+					 * Often, there are two cardbus bridges
+					 * -- try to leave one valid bus number
+					 * for each one.
+					 */
+					i /= 2;
+					break;
+				}
+			}
+			max += i;
+			pci_fixup_parent_subordinate_busnr(child, max);
+		}
+		/*
+		 * Set the subordinate bus number to its real value.
+		 */
+		child->subordinate = max;
+		pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
+	}
+
+	sprintf(child->name,
+		(is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
+		pci_domain_nr(bus), child->number);
+
+	/* Has only triggered on CardBus, fixup is in yenta_socket */
+	while (bus->parent) {
+		if ((child->subordinate > bus->subordinate) ||
+		    (child->number > bus->subordinate) ||
+		    (child->number < bus->number) ||
+		    (child->subordinate < bus->number)) {
+			dev_info(&child->dev, "[bus %02x-%02x] %s "
+				"hidden behind%s bridge %s [bus %02x-%02x]\n",
+				child->number, child->subordinate,
+				(bus->number > child->subordinate &&
+				 bus->subordinate < child->number) ?
+					"wholly" : "partially",
+				bus->self->transparent ? " transparent" : "",
+				dev_name(&bus->dev),
+				bus->number, bus->subordinate);
+		}
+		bus = bus->parent;
+	}
+
+out:
+	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
+
+	return max;
+}
+
+/*
+ * Read interrupt line and base address registers.
+ * The architecture-dependent code can tweak these, of course.
+ */
+static void pci_read_irq(struct pci_dev *dev)
+{
+	unsigned char irq;
+
+	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
+	dev->pin = irq;
+	if (irq)
+		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
+	dev->irq = irq;
+}
+
+void set_pcie_port_type(struct pci_dev *pdev)
+{
+	int pos;
+	u16 reg16;
+
+	pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
+	if (!pos)
+		return;
+	pdev->is_pcie = 1;
+	pdev->pcie_cap = pos;
+	pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
+	pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4;
+	pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, &reg16);
+	pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
+}
+
+void set_pcie_hotplug_bridge(struct pci_dev *pdev)
+{
+	int pos;
+	u16 reg16;
+	u32 reg32;
+
+	pos = pci_pcie_cap(pdev);
+	if (!pos)
+		return;
+	pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
+	if (!(reg16 & PCI_EXP_FLAGS_SLOT))
+		return;
+	pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &reg32);
+	if (reg32 & PCI_EXP_SLTCAP_HPC)
+		pdev->is_hotplug_bridge = 1;
+}
+
+#define LEGACY_IO_RESOURCE	(IORESOURCE_IO | IORESOURCE_PCI_FIXED)
+
+/**
+ * pci_setup_device - fill in class and map information of a device
+ * @dev: the device structure to fill
+ *
+ * Initialize the device structure with information about the device's 
+ * vendor,class,memory and IO-space addresses,IRQ lines etc.
+ * Called at initialisation of the PCI subsystem and by CardBus services.
+ * Returns 0 on success and negative if unknown type of device (not normal,
+ * bridge or CardBus).
+ */
+int pci_setup_device(struct pci_dev *dev)
+{
+	u32 class;
+	u8 hdr_type;
+	struct pci_slot *slot;
+	int pos = 0;
+	struct pci_bus_region region;
+	struct resource *res;
+
+	if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
+		return -EIO;
+
+	dev->sysdata = dev->bus->sysdata;
+	dev->dev.parent = dev->bus->bridge;
+	dev->dev.bus = &pci_bus_type;
+	dev->hdr_type = hdr_type & 0x7f;
+	dev->multifunction = !!(hdr_type & 0x80);
+	dev->error_state = pci_channel_io_normal;
+	set_pcie_port_type(dev);
+
+	list_for_each_entry(slot, &dev->bus->slots, list)
+		if (PCI_SLOT(dev->devfn) == slot->number)
+			dev->slot = slot;
+
+	/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
+	   set this higher, assuming the system even supports it.  */
+	dev->dma_mask = 0xffffffff;
+
+	dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
+		     dev->bus->number, PCI_SLOT(dev->devfn),
+		     PCI_FUNC(dev->devfn));
+
+	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
+	dev->revision = class & 0xff;
+	dev->class = class >> 8;		    /* upper 3 bytes */
+
+	dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
+		   dev->vendor, dev->device, dev->hdr_type, dev->class);
+
+	/* need to have dev->class ready */
+	dev->cfg_size = pci_cfg_space_size(dev);
+
+	/* "Unknown power state" */
+	dev->current_state = PCI_UNKNOWN;
+
+	/* Early fixups, before probing the BARs */
+	pci_fixup_device(pci_fixup_early, dev);
+	/* device class may be changed after fixup */
+	class = dev->class >> 8;
+
+	switch (dev->hdr_type) {		    /* header type */
+	case PCI_HEADER_TYPE_NORMAL:		    /* standard header */
+		if (class == PCI_CLASS_BRIDGE_PCI)
+			goto bad;
+		pci_read_irq(dev);
+		pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
+		pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
+		pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
+
+		/*
+		 *	Do the ugly legacy mode stuff here rather than broken chip
+		 *	quirk code. Legacy mode ATA controllers have fixed
+		 *	addresses. These are not always echoed in BAR0-3, and
+		 *	BAR0-3 in a few cases contain junk!
+		 */
+		if (class == PCI_CLASS_STORAGE_IDE) {
+			u8 progif;
+			pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
+			if ((progif & 1) == 0) {
+				region.start = 0x1F0;
+				region.end = 0x1F7;
+				res = &dev->resource[0];
+				res->flags = LEGACY_IO_RESOURCE;
+				pcibios_bus_to_resource(dev, res, &region);
+				region.start = 0x3F6;
+				region.end = 0x3F6;
+				res = &dev->resource[1];
+				res->flags = LEGACY_IO_RESOURCE;
+				pcibios_bus_to_resource(dev, res, &region);
+			}
+			if ((progif & 4) == 0) {
+				region.start = 0x170;
+				region.end = 0x177;
+				res = &dev->resource[2];
+				res->flags = LEGACY_IO_RESOURCE;
+				pcibios_bus_to_resource(dev, res, &region);
+				region.start = 0x376;
+				region.end = 0x376;
+				res = &dev->resource[3];
+				res->flags = LEGACY_IO_RESOURCE;
+				pcibios_bus_to_resource(dev, res, &region);
+			}
+		}
+		break;
+
+	case PCI_HEADER_TYPE_BRIDGE:		    /* bridge header */
+		if (class != PCI_CLASS_BRIDGE_PCI)
+			goto bad;
+		/* The PCI-to-PCI bridge spec requires that subtractive
+		   decoding (i.e. transparent) bridge must have programming
+		   interface code of 0x01. */ 
+		pci_read_irq(dev);
+		dev->transparent = ((dev->class & 0xff) == 1);
+		pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
+		set_pcie_hotplug_bridge(dev);
+		pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
+		if (pos) {
+			pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
+			pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
+		}
+		break;
+
+	case PCI_HEADER_TYPE_CARDBUS:		    /* CardBus bridge header */
+		if (class != PCI_CLASS_BRIDGE_CARDBUS)
+			goto bad;
+		pci_read_irq(dev);
+		pci_read_bases(dev, 1, 0);
+		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
+		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
+		break;
+
+	default:				    /* unknown header */
+		dev_err(&dev->dev, "unknown header type %02x, "
+			"ignoring device\n", dev->hdr_type);
+		return -EIO;
+
+	bad:
+		dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
+			"type %02x)\n", dev->class, dev->hdr_type);
+		dev->class = PCI_CLASS_NOT_DEFINED;
+	}
+
+	/* We found a fine healthy device, go go go... */
+	return 0;
+}
+
+static void pci_release_capabilities(struct pci_dev *dev)
+{
+	pci_vpd_release(dev);
+	pci_iov_release(dev);
+	pci_free_cap_save_buffers(dev);
+}
+
+/**
+ * pci_release_dev - free a pci device structure when all users of it are finished.
+ * @dev: device that's been disconnected
+ *
+ * Will be called only by the device core when all users of this pci device are
+ * done.
+ */
+static void pci_release_dev(struct device *dev)
+{
+	struct pci_dev *pci_dev;
+
+	pci_dev = to_pci_dev(dev);
+	pci_release_capabilities(pci_dev);
+	pci_release_of_node(pci_dev);
+	kfree(pci_dev);
+}
+
+/**
+ * pci_cfg_space_size - get the configuration space size of the PCI device.
+ * @dev: PCI device
+ *
+ * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
+ * have 4096 bytes.  Even if the device is capable, that doesn't mean we can
+ * access it.  Maybe we don't have a way to generate extended config space
+ * accesses, or the device is behind a reverse Express bridge.  So we try
+ * reading the dword at 0x100 which must either be 0 or a valid extended
+ * capability header.
+ */
+int pci_cfg_space_size_ext(struct pci_dev *dev)
+{
+	u32 status;
+	int pos = PCI_CFG_SPACE_SIZE;
+
+	if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
+		goto fail;
+	if (status == 0xffffffff)
+		goto fail;
+
+	return PCI_CFG_SPACE_EXP_SIZE;
+
+ fail:
+	return PCI_CFG_SPACE_SIZE;
+}
+
+int pci_cfg_space_size(struct pci_dev *dev)
+{
+	int pos;
+	u32 status;
+	u16 class;
+
+	class = dev->class >> 8;
+	if (class == PCI_CLASS_BRIDGE_HOST)
+		return pci_cfg_space_size_ext(dev);
+
+	pos = pci_pcie_cap(dev);
+	if (!pos) {
+		pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
+		if (!pos)
+			goto fail;
+
+		pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
+		if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
+			goto fail;
+	}
+
+	return pci_cfg_space_size_ext(dev);
+
+ fail:
+	return PCI_CFG_SPACE_SIZE;
+}
+
+static void pci_release_bus_bridge_dev(struct device *dev)
+{
+	kfree(dev);
+}
+
+struct pci_dev *alloc_pci_dev(void)
+{
+	struct pci_dev *dev;
+
+	dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	INIT_LIST_HEAD(&dev->bus_list);
+
+	return dev;
+}
+EXPORT_SYMBOL(alloc_pci_dev);
+
+bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
+				 int crs_timeout)
+{
+	int delay = 1;
+
+	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
+		return false;
+
+	/* some broken boards return 0 or ~0 if a slot is empty: */
+	if (*l == 0xffffffff || *l == 0x00000000 ||
+	    *l == 0x0000ffff || *l == 0xffff0000)
+		return false;
+
+	/* Configuration request Retry Status */
+	while (*l == 0xffff0001) {
+		if (!crs_timeout)
+			return false;
+
+		msleep(delay);
+		delay *= 2;
+		if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
+			return false;
+		/* Card hasn't responded in 60 seconds?  Must be stuck. */
+		if (delay > crs_timeout) {
+			printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
+					"responding\n", pci_domain_nr(bus),
+					bus->number, PCI_SLOT(devfn),
+					PCI_FUNC(devfn));
+			return false;
+		}
+	}
+
+	return true;
+}
+EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
+
+/*
+ * Read the config data for a PCI device, sanity-check it
+ * and fill in the dev structure...
+ */
+static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
+{
+	struct pci_dev *dev;
+	u32 l;
+
+	if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
+		return NULL;
+
+	dev = alloc_pci_dev();
+	if (!dev)
+		return NULL;
+
+	dev->bus = bus;
+	dev->devfn = devfn;
+	dev->vendor = l & 0xffff;
+	dev->device = (l >> 16) & 0xffff;
+
+	pci_set_of_node(dev);
+
+	if (pci_setup_device(dev)) {
+		kfree(dev);
+		return NULL;
+	}
+
+	return dev;
+}
+
+static void pci_init_capabilities(struct pci_dev *dev)
+{
+	/* MSI/MSI-X list */
+	pci_msi_init_pci_dev(dev);
+
+	/* Buffers for saving PCIe and PCI-X capabilities */
+	pci_allocate_cap_save_buffers(dev);
+
+	/* Power Management */
+	pci_pm_init(dev);
+	platform_pci_wakeup_init(dev);
+
+	/* Vital Product Data */
+	pci_vpd_pci22_init(dev);
+
+	/* Alternative Routing-ID Forwarding */
+	pci_enable_ari(dev);
+
+	/* Single Root I/O Virtualization */
+	pci_iov_init(dev);
+
+	/* Enable ACS P2P upstream forwarding */
+	pci_enable_acs(dev);
+}
+
+void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
+{
+	device_initialize(&dev->dev);
+	dev->dev.release = pci_release_dev;
+	pci_dev_get(dev);
+
+	dev->dev.dma_mask = &dev->dma_mask;
+	dev->dev.dma_parms = &dev->dma_parms;
+	dev->dev.coherent_dma_mask = 0xffffffffull;
+
+	pci_set_dma_max_seg_size(dev, 65536);
+	pci_set_dma_seg_boundary(dev, 0xffffffff);
+
+	/* Fix up broken headers */
+	pci_fixup_device(pci_fixup_header, dev);
+
+	/* moved out from quirk header fixup code */
+	pci_reassigndev_resource_alignment(dev);
+
+	/* Clear the state_saved flag. */
+	dev->state_saved = false;
+
+	/* Initialize various capabilities */
+	pci_init_capabilities(dev);
+
+	/*
+	 * Add the device to our list of discovered devices
+	 * and the bus list for fixup functions, etc.
+	 */
+	down_write(&pci_bus_sem);
+	list_add_tail(&dev->bus_list, &bus->devices);
+	up_write(&pci_bus_sem);
+}
+
+struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
+{
+	struct pci_dev *dev;
+
+	dev = pci_get_slot(bus, devfn);
+	if (dev) {
+		pci_dev_put(dev);
+		return dev;
+	}
+
+	dev = pci_scan_device(bus, devfn);
+	if (!dev)
+		return NULL;
+
+	pci_device_add(dev, bus);
+
+	return dev;
+}
+EXPORT_SYMBOL(pci_scan_single_device);
+
+static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
+{
+	u16 cap;
+	unsigned pos, next_fn;
+
+	if (!dev)
+		return 0;
+
+	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
+	if (!pos)
+		return 0;
+	pci_read_config_word(dev, pos + 4, &cap);
+	next_fn = cap >> 8;
+	if (next_fn <= fn)
+		return 0;
+	return next_fn;
+}
+
+static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
+{
+	return (fn + 1) % 8;
+}
+
+static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
+{
+	return 0;
+}
+
+static int only_one_child(struct pci_bus *bus)
+{
+	struct pci_dev *parent = bus->self;
+	if (!parent || !pci_is_pcie(parent))
+		return 0;
+	if (parent->pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
+	    parent->pcie_type == PCI_EXP_TYPE_DOWNSTREAM)
+		return 1;
+	return 0;
+}
+
+/**
+ * pci_scan_slot - scan a PCI slot on a bus for devices.
+ * @bus: PCI bus to scan
+ * @devfn: slot number to scan (must have zero function.)
+ *
+ * Scan a PCI slot on the specified PCI bus for devices, adding
+ * discovered devices to the @bus->devices list.  New devices
+ * will not have is_added set.
+ *
+ * Returns the number of new devices found.
+ */
+int pci_scan_slot(struct pci_bus *bus, int devfn)
+{
+	unsigned fn, nr = 0;
+	struct pci_dev *dev;
+	unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
+
+	if (only_one_child(bus) && (devfn > 0))
+		return 0; /* Already scanned the entire slot */
+
+	dev = pci_scan_single_device(bus, devfn);
+	if (!dev)
+		return 0;
+	if (!dev->is_added)
+		nr++;
+
+	if (pci_ari_enabled(bus))
+		next_fn = next_ari_fn;
+	else if (dev->multifunction)
+		next_fn = next_trad_fn;
+
+	for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
+		dev = pci_scan_single_device(bus, devfn + fn);
+		if (dev) {
+			if (!dev->is_added)
+				nr++;
+			dev->multifunction = 1;
+		}
+	}
+
+	/* only one slot has pcie device */
+	if (bus->self && nr)
+		pcie_aspm_init_link_state(bus->self);
+
+	return nr;
+}
+
+static int pcie_find_smpss(struct pci_dev *dev, void *data)
+{
+	u8 *smpss = data;
+
+	if (!pci_is_pcie(dev))
+		return 0;
+
+	/* For PCIE hotplug enabled slots not connected directly to a
+	 * PCI-E root port, there can be problems when hotplugging
+	 * devices.  This is due to the possibility of hotplugging a
+	 * device into the fabric with a smaller MPS that the devices
+	 * currently running have configured.  Modifying the MPS on the
+	 * running devices could cause a fatal bus error due to an
+	 * incoming frame being larger than the newly configured MPS.
+	 * To work around this, the MPS for the entire fabric must be
+	 * set to the minimum size.  Any devices hotplugged into this
+	 * fabric will have the minimum MPS set.  If the PCI hotplug
+	 * slot is directly connected to the root port and there are not
+	 * other devices on the fabric (which seems to be the most
+	 * common case), then this is not an issue and MPS discovery
+	 * will occur as normal.
+	 */
+	if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
+	     (dev->bus->self &&
+	      dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)))
+		*smpss = 0;
+
+	if (*smpss > dev->pcie_mpss)
+		*smpss = dev->pcie_mpss;
+
+	return 0;
+}
+
+static void pcie_write_mps(struct pci_dev *dev, int mps)
+{
+	int rc;
+
+	if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
+		mps = 128 << dev->pcie_mpss;
+
+		if (dev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && dev->bus->self)
+			/* For "Performance", the assumption is made that
+			 * downstream communication will never be larger than
+			 * the MRRS.  So, the MPS only needs to be configured
+			 * for the upstream communication.  This being the case,
+			 * walk from the top down and set the MPS of the child
+			 * to that of the parent bus.
+			 *
+			 * Configure the device MPS with the smaller of the
+			 * device MPSS or the bridge MPS (which is assumed to be
+			 * properly configured at this point to the largest
+			 * allowable MPS based on its parent bus).
+			 */
+			mps = min(mps, pcie_get_mps(dev->bus->self));
+	}
+
+	rc = pcie_set_mps(dev, mps);
+	if (rc)
+		dev_err(&dev->dev, "Failed attempting to set the MPS\n");
+}
+
+static void pcie_write_mrrs(struct pci_dev *dev)
+{
+	int rc, mrrs;
+
+	/* In the "safe" case, do not configure the MRRS.  There appear to be
+	 * issues with setting MRRS to 0 on a number of devices.
+	 */
+	if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
+		return;
+
+	/* For Max performance, the MRRS must be set to the largest supported
+	 * value.  However, it cannot be configured larger than the MPS the
+	 * device or the bus can support.  This should already be properly
+	 * configured by a prior call to pcie_write_mps.
+	 */
+	mrrs = pcie_get_mps(dev);
+
+	/* MRRS is a R/W register.  Invalid values can be written, but a
+	 * subsequent read will verify if the value is acceptable or not.
+	 * If the MRRS value provided is not acceptable (e.g., too large),
+	 * shrink the value until it is acceptable to the HW.
+ 	 */
+	while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
+		rc = pcie_set_readrq(dev, mrrs);
+		if (!rc)
+			break;
+
+		dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
+		mrrs /= 2;
+	}
+
+	if (mrrs < 128)
+		dev_err(&dev->dev, "MRRS was unable to be configured with a "
+			"safe value.  If problems are experienced, try running "
+			"with pci=pcie_bus_safe.\n");
+}
+
+static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
+{
+	int mps, orig_mps;
+
+	if (!pci_is_pcie(dev))
+		return 0;
+
+	mps = 128 << *(u8 *)data;
+	orig_mps = pcie_get_mps(dev);
+
+	pcie_write_mps(dev, mps);
+	pcie_write_mrrs(dev);
+
+	dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
+		 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
+		 orig_mps, pcie_get_readrq(dev));
+
+	return 0;
+}
+
+/* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
+ * parents then children fashion.  If this changes, then this code will not
+ * work as designed.
+ */
+void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
+{
+	u8 smpss;
+
+	if (!pci_is_pcie(bus->self))
+		return;
+
+	if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
+		return;
+
+	/* FIXME - Peer to peer DMA is possible, though the endpoint would need
+	 * to be aware to the MPS of the destination.  To work around this,
+	 * simply force the MPS of the entire system to the smallest possible.
+	 */
+	if (pcie_bus_config == PCIE_BUS_PEER2PEER)
+		smpss = 0;
+
+	if (pcie_bus_config == PCIE_BUS_SAFE) {
+		smpss = mpss;
+
+		pcie_find_smpss(bus->self, &smpss);
+		pci_walk_bus(bus, pcie_find_smpss, &smpss);
+	}
+
+	pcie_bus_configure_set(bus->self, &smpss);
+	pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
+}
+EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
+
+unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
+{
+	unsigned int devfn, pass, max = bus->secondary;
+	struct pci_dev *dev;
+
+	dev_dbg(&bus->dev, "scanning bus\n");
+
+	/* Go find them, Rover! */
+	for (devfn = 0; devfn < 0x100; devfn += 8)
+		pci_scan_slot(bus, devfn);
+
+	/* Reserve buses for SR-IOV capability. */
+	max += pci_iov_bus_range(bus);
+
+	/*
+	 * After performing arch-dependent fixup of the bus, look behind
+	 * all PCI-to-PCI bridges on this bus.
+	 */
+	if (!bus->is_added) {
+		dev_dbg(&bus->dev, "fixups for bus\n");
+		pcibios_fixup_bus(bus);
+		if (pci_is_root_bus(bus))
+			bus->is_added = 1;
+	}
+
+	for (pass=0; pass < 2; pass++)
+		list_for_each_entry(dev, &bus->devices, bus_list) {
+			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+			    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+				max = pci_scan_bridge(bus, dev, max, pass);
+		}
+
+	/*
+	 * We've scanned the bus and so we know all about what's on
+	 * the other side of any bridges that may be on this bus plus
+	 * any devices.
+	 *
+	 * Return how far we've got finding sub-buses.
+	 */
+	dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
+	return max;
+}
+
+struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
+		struct pci_ops *ops, void *sysdata, struct list_head *resources)
+{
+	int error;
+	struct pci_host_bridge *bridge;
+	struct pci_bus *b, *b2;
+	struct device *dev;
+	struct pci_host_bridge_window *window, *n;
+	struct resource *res;
+	resource_size_t offset;
+	char bus_addr[64];
+	char *fmt;
+
+	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
+	if (!bridge)
+		return NULL;
+
+	b = pci_alloc_bus();
+	if (!b)
+		goto err_bus;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		goto err_dev;
+
+	b->sysdata = sysdata;
+	b->ops = ops;
+
+	b2 = pci_find_bus(pci_domain_nr(b), bus);
+	if (b2) {
+		/* If we already got to this bus through a different bridge, ignore it */
+		dev_dbg(&b2->dev, "bus already known\n");
+		goto err_out;
+	}
+
+	dev->parent = parent;
+	dev->release = pci_release_bus_bridge_dev;
+	dev_set_name(dev, "pci%04x:%02x", pci_domain_nr(b), bus);
+	error = device_register(dev);
+	if (error)
+		goto dev_reg_err;
+	b->bridge = get_device(dev);
+	device_enable_async_suspend(b->bridge);
+	pci_set_bus_of_node(b);
+
+	if (!parent)
+		set_dev_node(b->bridge, pcibus_to_node(b));
+
+	b->dev.class = &pcibus_class;
+	b->dev.parent = b->bridge;
+	dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
+	error = device_register(&b->dev);
+	if (error)
+		goto class_dev_reg_err;
+
+	/* Create legacy_io and legacy_mem files for this bus */
+	pci_create_legacy_files(b);
+
+	b->number = b->secondary = bus;
+
+	bridge->bus = b;
+	INIT_LIST_HEAD(&bridge->windows);
+
+	if (parent)
+		dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
+	else
+		printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
+
+	/* Add initial resources to the bus */
+	list_for_each_entry_safe(window, n, resources, list) {
+		list_move_tail(&window->list, &bridge->windows);
+		res = window->res;
+		offset = window->offset;
+		pci_bus_add_resource(b, res, 0);
+		if (offset) {
+			if (resource_type(res) == IORESOURCE_IO)
+				fmt = " (bus address [%#06llx-%#06llx])";
+			else
+				fmt = " (bus address [%#010llx-%#010llx])";
+			snprintf(bus_addr, sizeof(bus_addr), fmt,
+				 (unsigned long long) (res->start - offset),
+				 (unsigned long long) (res->end - offset));
+		} else
+			bus_addr[0] = '\0';
+		dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
+	}
+
+	down_write(&pci_bus_sem);
+	list_add_tail(&bridge->list, &pci_host_bridges);
+	list_add_tail(&b->node, &pci_root_buses);
+	up_write(&pci_bus_sem);
+
+	return b;
+
+class_dev_reg_err:
+	device_unregister(dev);
+dev_reg_err:
+	down_write(&pci_bus_sem);
+	list_del(&bridge->list);
+	list_del(&b->node);
+	up_write(&pci_bus_sem);
+err_out:
+	kfree(dev);
+err_dev:
+	kfree(b);
+err_bus:
+	kfree(bridge);
+	return NULL;
+}
+
+struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
+		struct pci_ops *ops, void *sysdata, struct list_head *resources)
+{
+	struct pci_bus *b;
+
+	b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
+	if (!b)
+		return NULL;
+
+	b->subordinate = pci_scan_child_bus(b);
+	pci_bus_add_devices(b);
+	return b;
+}
+EXPORT_SYMBOL(pci_scan_root_bus);
+
+/* Deprecated; use pci_scan_root_bus() instead */
+struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
+		int bus, struct pci_ops *ops, void *sysdata)
+{
+	LIST_HEAD(resources);
+	struct pci_bus *b;
+
+	pci_add_resource(&resources, &ioport_resource);
+	pci_add_resource(&resources, &iomem_resource);
+	b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
+	if (b)
+		b->subordinate = pci_scan_child_bus(b);
+	else
+		pci_free_resource_list(&resources);
+	return b;
+}
+EXPORT_SYMBOL(pci_scan_bus_parented);
+
+struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *ops,
+					void *sysdata)
+{
+	LIST_HEAD(resources);
+	struct pci_bus *b;
+
+	pci_add_resource(&resources, &ioport_resource);
+	pci_add_resource(&resources, &iomem_resource);
+	b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
+	if (b) {
+		b->subordinate = pci_scan_child_bus(b);
+		pci_bus_add_devices(b);
+	} else {
+		pci_free_resource_list(&resources);
+	}
+	return b;
+}
+EXPORT_SYMBOL(pci_scan_bus);
+
+#ifdef CONFIG_HOTPLUG
+/**
+ * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
+ * @bridge: PCI bridge for the bus to scan
+ *
+ * Scan a PCI bus and child buses for new devices, add them,
+ * and enable them, resizing bridge mmio/io resource if necessary
+ * and possible.  The caller must ensure the child devices are already
+ * removed for resizing to occur.
+ *
+ * Returns the max number of subordinate bus discovered.
+ */
+unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
+{
+	unsigned int max;
+	struct pci_bus *bus = bridge->subordinate;
+
+	max = pci_scan_child_bus(bus);
+
+	pci_assign_unassigned_bridge_resources(bridge);
+
+	pci_bus_add_devices(bus);
+
+	return max;
+}
+
+EXPORT_SYMBOL(pci_add_new_bus);
+EXPORT_SYMBOL(pci_scan_slot);
+EXPORT_SYMBOL(pci_scan_bridge);
+EXPORT_SYMBOL_GPL(pci_scan_child_bus);
+#endif
+
+static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
+{
+	const struct pci_dev *a = to_pci_dev(d_a);
+	const struct pci_dev *b = to_pci_dev(d_b);
+
+	if      (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
+	else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return  1;
+
+	if      (a->bus->number < b->bus->number) return -1;
+	else if (a->bus->number > b->bus->number) return  1;
+
+	if      (a->devfn < b->devfn) return -1;
+	else if (a->devfn > b->devfn) return  1;
+
+	return 0;
+}
+
+void __init pci_sort_breadthfirst(void)
+{
+	bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
+}