Take advantage of some gaps in the table to fit in support for AGP speeds.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Both PCIe and PCI-X bridges report their secondary bus speed in their
respective capabilities.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Move the max_bus_speed and cur_bus_speed into the pci_bus. Expose the
values through the PCI slot driver instead of the hotplug slot driver.
Update all the hotplug drivers to use the pci_bus instead of their own
data structures.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The Alternate Routing-ID Interpretation capability allows a single device
to have up to 256 functions. They can be populated sparsely, so the
current technique of scanning every eighth function is not guaranteed
to find them all. By introducing a 'next_fn' function pointer, we can
use the linked list of functions in the ARI capability to scan all the
functions which exist.
We can then speed up the pci_scan_slot by skipping the scan of subsequent
devfns for PCIe devices which are the direct children of Root Ports or
Downstream Ports. These devices are only permitted to implement device
0, unless they are ARI devices, in which case they'll be scanned by the
ARI code above.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We are missing these when building the pci_dev from scratch off
the Open Firmware device-tree
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Commit ae21ee65e8 "PCI: acs p2p upsteram
forwarding enabling" doesn't actually enable ACS.
Add a function to pci core to allow an IOMMU to request that ACS
be enabled. The existing mechanism of using iommu_found() in the pci
core to know when ACS should be enabled doesn't actually work due to
initialization order; iommu has only been detected not initialized.
Have Intel and AMD IOMMUs request ACS, and Xen does as well during early
init of dom0.
Cc: Allen Kay <allen.m.kay@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Use pcie_cap() instead of pci_find_capability() to get PCIe capability
offset in PCI core code. This avoids unnecessary search in PCI
configuration space.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
There are a lot of codes that searches PCI express capability offset
in the PCI configuration space using pci_find_capability(). Caching it
in the struct pci_dev will reduce unncecessary search. This patch adds
an additional 'pcie_cap' fields into struct pci_dev, which is
initialized at pci device scan time (in set_pcie_port_type()).
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This makes PCI resource management messages more consistent and adds a few
new messages to aid debugging.
Whenever we assign resources to a device, update a BAR, or change a
bridge aperture, it's worth noting it.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Since we have a struct device, we might as well use dev_printk. Note that
both pr_debug() and dev_dbg() are completely compiled out unless DEBUG or
DYNAMIC_DEBUG is defined.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Jesse accidentally applied v1 [1] of the patchset instead of v2 [2]. This
is the diff between v1 and v2.
The changes in this patch are:
- tidied vsprintf stack buffer to shrink and compute size more
accurately
- use %pR for decoding and %pr for "raw" (with type and flags) instead
of adding %pRt and %pRf
[1] http://lkml.org/lkml/2009/10/6/491
[2] http://lkml.org/lkml/2009/10/13/441
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Change to populate the subsystem vendor and subsytem device IDs for
PCI-PCI bridges that implement the PCI Subsystem Vendor ID capability.
Previously bridges left subsystem vendor IDs unpopulated.
Signed-off-by: Gabe Black <gabe.black@ni.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Feedback from Hidetoshi Seto and Kenji Kaneshige incorporated. This
correctly handles PCI-X bridges, PCIe root ports and endpoints, and
prints debug messages when invalid/reserved types are found in the
HEST. PCI devices not in domain/segment 0 are not represented in
HEST, thus will be ignored.
Today, the PCIe Advanced Error Reporting (AER) driver attaches itself
to every PCIe root port for which BIOS reports it should, via ACPI
_OSC.
However, _OSC alone is insufficient for newer BIOSes. Part of ACPI
4.0 is the new APEI (ACPI Platform Error Interfaces) which is a way
for OS and BIOS to handshake over which errors for which components
each will handle. One table in ACPI 4.0 is the Hardware Error Source
Table (HEST), where BIOS can define that errors for certain PCIe
devices (or all devices), should be handled by BIOS ("Firmware First
mode"), rather than be handled by the OS.
Dell PowerEdge 11G server BIOS defines Firmware First mode in HEST, so
that it may manage such errors, log them to the System Event Log, and
possibly take other actions. The aer driver should honor this, and
not attach itself to devices noted as such.
Furthermore, Kenji Kaneshige reminded us to disallow changing the AER
registers when respecting Firmware First mode. Platform firmware is
expected to manage these, and if changes to them are allowed, it could
break that firmware's behavior.
The HEST parsing code may be replaced in the future by a more
feature-rich implementation. This patch provides the minimum needed
to prevent breakage until that implementation is available.
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
When probing for ROM BAR size, we should not change bits 1:10 in this
BAR, because these bits are marked as "reserved for future use" in PCI
spec, so changing them might have side effects.
No such issue for I/O or memory, as there is an implementation note in
PCI spec which explicitly allows writing 0xfffffffff there.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch is predicated on Jeremy's patch in include/xen/xen.h. It'll
prevent ACS init unless the platform has both an IOMMU and we're running
as dom0.
Signed-off-by: Allen Kay <allen.m.kay@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Note: dom0 checking in v4 has been separated out into 2/2.
This patch enables P2P upstream forwarding in ACS capable PCIe switches.
It solves two potential problems in virtualization environment where a PCIe
device is assigned to a guest domain using a HW iommu such as VT-d:
1) Unintentional failure caused by guest physical address programmed
into the device's DMA that happens to match the memory address range
of other downstream ports in the same PCIe switch. This causes the PCI
transaction to go to the matching downstream port instead of go to the
root complex to get translated by VT-d as it should be.
2) Malicious guest software intentionally attacks another downstream
PCIe device by programming the DMA address into the assigned device
that matches memory address range of the downstream PCIe port.
We are in process of implementing device filtering software in KVM/XEN
management software to allow device assignment of PCIe devices behind a PCIe
switch only if it has ACS capability and with the P2P upstream forwarding bits
enabled. This patch is intended to work for both KVM and Xen environments.
Signed-off-by: Allen Kay <allen.m.kay@intel.com>
Reviewed-by: Mathew Wilcox <willy@linux.intel.com>
Reviewed-by: Chris Wright <chris@sous-sol.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some PCI devices fail if their standard configuration registers are
restored twice in a row. Prevent this from happening by making
pci_restore_state() clear the saved_state flag of the device right
after the device's standard configuration registers have been
populated with the previously saved values.
Simplify PCI PM callbacks by removing the direct clearing of
state_saved from them, as it shouldn't be necessary any more (except
in pci_pm_thaw(), where it has to be cleared, so that the values saved
during the "freeze" phase of hibernation are not used later by mistake).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
In general a BIOS may goof or we may hotplug in a hotplug controller.
In either case the kernel needs to reserve resources for plugging
in more devices in the future instead of creating a minimal resource
assignment.
We already do this for cardbus bridges I am just adding a variant
for pcie bridges.
v2: Make testing for pcie hotplug bridges based on a flag.
So far we only set the flag for pcie but a header_quirk
could easily be added for the non-standard pci hotplug
bridges.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We already print it out for pci bridges, so also print it out for pci devices.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This was #define'd as 0 on all platforms, so let's get rid of it.
This change makes pci_scan_slot() slightly easier to read.
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Use pci_is_root_bus() in pci_read_bridge_bases() to check if the pci
bus is root, for code consistency.
Reviewed-by: Alex Chiang <achiang@hp.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We should not assign 64bit ranges to PCI devices that only take 32bit
prefetchable addresses.
Try to set IORESOURCE_MEM_64 in 64bit resource of pci_device/pci_bridge
and make the bus resource only have that bit set when all devices under
it support 64bit prefetchable memory. Use that flag to allocate
resources from that range.
Reported-by: Yannick <yannick.roehlly@free.fr>
Reviewed-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The device class may be changed after the fixup, so re-read the class
value from pci_dev when configuring the device. Otherwise some devices
such as JMicron SATA controller won't work.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Commit 30a18d6c3f introduced a new
function to set the PCI bus resources. Unfortunately, neither the
author, nor the committers seemed to know that we already have somewhere
to do that -- pcibios_fixup_bus(). This patch moves the hook (used only
by the K8 code) into x86-specific code where it should have been in the
first place.
Cc: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_rescan_bus was annotated as __devinit, which is wrong,
because it will never be part of device initialization.
Howevever, we can't simply drop the annotation, because then we
get section warnings about calling pci_scan_child_bus (which is
correctly marked as __devinit).
pci_rescan_bus will only get built when CONFIG_HOTPLUG is set,
meaning that __devinit is a nop, so we know that pci_scan_child_bus
has not been freed.
Annotate as __ref to silence modpost.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
New pci_cfg_space_size() needs invalid pdev->class, put it in the
right place in the pci_setup_device().
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This interface allows the user to force a rescan of all PCI buses
in system, and rediscover devices that have been removed earlier.
pci_bus_attrs implementation from Trent Piepho.
Thanks to Vegard Nossum for discovering locking issues with the
sysfs interface.
Cc: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This API is used by the PCI core to rescan a bus and rediscover
newly added devices.
Over time, it is expected that the various PCI hotplug drivers
will migrate to this interface and away from the old
pci_do_scan_bus() interface.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
While scanning bridges, we stop our scan if we encounter a bus
that we've seen before, to work around some buggy chipsets. This
is a good idea, but prevents us from fully scanning the PCI bus
at a future time (to find newly hot-added devices, for example).
Change the logic so that we skip _re-adding_ an existing bus
that we've seen before, but also allow the scan to descend to
all child buses.
Now that we're potentially scanning our child buses again, we
also need to be sure not to attempt re-initializing their BARs
so we avoid that.
This patch lays the groundwork to allow the user to issue a
rescan of the PCI bus at any time.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_scan_slot() has been rewritten to be less complex and will now
return the number of *new* devices found.
Existing callers need not worry because they already assume that
they can't call pci_scan_slot() on an already-scanned slot.
Thus, there is no semantic change for existing callers: returning
newly found devices (this patch) is exactly equal to returning all
found devices (before this patch).
This patch adds some more groundwork to allow us to rescan the
PCI bus during runtime to discover newly added devices.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_scan_single_device is supposed to add newly discovered
devices to pci_bus->devices, but doesn't check to see if the
device has already been added. This can cause problems if we ever
want to use this interface to rescan the PCI bus.
If the device is already added, just return it.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Move the device setup stuff into pci_setup_device() which will be used
to setup the Virtual Function later.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reserve the bus number range used by the Virtual Function when
pcibios_assign_all_busses() returns true.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
If a device has the SR-IOV capability, initialize it (set the ARI
Capable Hierarchy in the lowest numbered PF if necessary; calculate
the System Page Size for the VF MMIO, probe the VF Offset, Stride
and BARs). A lock for the VF bus allocation is also initialized if
a PF is the lowest numbered PF.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Many host bridges support a 4k config space, so check them directy
instead of using quirks to add them.
We only need to do this extra check for host bridges at this point,
because only host bridges are known to have extended address space
without also having a PCI-X/PCI-E caps. Other devices with this
property could be done with quirks (if there are any).
As a bonus, we can remove the quirks for AMD host bridges with family
10h and 11h since they're not needed any more.
With this patch, we can get correct pci cfg size of new Intel CPUs/IOHs
with host bridges.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Current pci_read_bridge_bases() has an assumption that pci_bus->self
is NULL on the pci root bus (It checks pci_bus->self to see if the pci
bus is root bus). But is might not true on some platforms. We must
check pci_bus->parent instead.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'cpus4096-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
[IA64] fix typo in cpumask_of_pcibus()
x86: fix x86_32 builds for summit and es7000 arch's
cpumask: use work_on_cpu in acpi-cpufreq.c for read_measured_perf_ctrs
cpumask: use work_on_cpu in acpi-cpufreq.c for drv_read and drv_write
cpumask: use cpumask_var_t in acpi-cpufreq.c
cpumask: use work_on_cpu in acpi/cstate.c
cpumask: convert struct cpufreq_policy to cpumask_var_t
cpumask: replace CPUMASK_ALLOC etc with cpumask_var_t
x86: cleanup remaining cpumask_t ops in smpboot code
cpumask: update pci_bus_show_cpuaffinity to use new cpumask API
cpumask: update local_cpus_show to use new cpumask API
ia64: cpumask fix for is_affinity_mask_valid()
When PCI devices are initialized, we check whether they support PCI PM
caps and set the device can_wakeup flag if so. However, some devices
may have platform provided wakeup events rather than PCI PME signals, so
we need to set can_wakeup in that case too. Doing so should allow
wakeups from many more devices, especially on cost constrained systems.
Reported-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Joseph Chan <JosephChan@via.com.tw>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Allow pci_alloc_child_bus() to allocate buses without bridge devices.
Some SR-IOV devices can occupy more than one bus number, but there is no
explicit bridges because that have internal routing mechanism.
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Export __pci_read_base() so it can be used by whole PCI subsystem.
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch moves all definitions of the PCI resource names to an 'enum',
and also replaces some hard-coded resource variables with symbol
names. This change eases introduction of device specific resources.
Reviewed-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Since interrupts will soon be disabled at PCI resume time, we need to
pre-allocate memory to save/restore PCI config space (or use GFP_ATOMIC,
but this is safer).
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch is part of a larger patch series which will remove
the "char bus_id[20]" name string from struct device. The device
name is managed in the kobject anyway, and without any size
limitation, and just needlessly copied into "struct device".
To set and read the device name dev_name(dev) and dev_set_name(dev)
must be used. If your code uses static kobjects, which it shouldn't
do, "const char *init_name" can be used to statically provide the
name the registered device should have. At registration time, the
init_name field is cleared, to enforce the use of dev_name(dev) to
access the device name at a later time.
We need to get rid of all occurrences of bus_id in the entire tree
to be able to enable the new interface. Please apply this patch,
and possibly convert any remaining remaining occurrences of bus_id.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: use new cpumask API to reduce stack usage
Replace the local cpumask_t variable with a pointer to the
const cpumask that needs to be printed.
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: change calling convention of existing cpumask APIs
Most cpumask functions started with cpus_: these have been replaced by
cpumask_ ones which take struct cpumask pointers as expected.
These four functions don't have good replacement names; fortunately
they're rarely used, so we just change them over.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: tony.luck@intel.com
Cc: ralf@linux-mips.org
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: cl@linux-foundation.org
Cc: srostedt@redhat.com
This cleanup removes the resource assignment in pci_read_bridge_bases()
since it has taken care by pci_alloc_child_bus() when allocating the bus:
/* Set up default resource pointers and names.. */
for (i = 0; i < PCI_BRIDGE_RES_NUM; i++) {
child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
child->resource[i]->name = child->name;
}
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Some firmware fail to properly configure P2P bridges, leaving them
with invalid bus numbers. In some cases, this happens on some embedded
4xx boards as the result of the kernel allocating different bus space
than the firmware does to host bridges while not setting
pcibios_assign_all_busses() for various reasons. In other cases, it can
just be bogus firmware.
This adds some sanity checking to the PCI probing code. If a bridge is
found whose primary bus number doesn't match the bus it's sitting on,
or whose secondary bus number not strictly above it's primary bus
number, then the bridge bus numbers are deconfigured in the first pass
of pci_scan_bridge() to be re-assigned in the second pass.
Tested-by: "Ayman El-Khashab" <AymanE@tanisys.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
