Using %pR standardizes the struct resource output.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
machine is compatible is an OF-specific call. It should have
the of_ prefix to protect the global namespace.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Michal Simek <monstr@monstr.eu>
Fix the following 3 issues:
arch/powerpc/kernel/process.c: In function 'arch_randomize_brk':
arch/powerpc/kernel/process.c:1183: error: 'mmu_highuser_ssize' undeclared (first use in this function)
arch/powerpc/kernel/process.c:1183: error: (Each undeclared identifier is reported only once
arch/powerpc/kernel/process.c:1183: error: for each function it appears in.)
arch/powerpc/kernel/process.c:1183: error: 'MMU_SEGSIZE_1T' undeclared (first use in this function)
In file included from arch/powerpc/kernel/setup_64.c:60:
arch/powerpc/include/asm/mmu-hash64.h:132: error: redefinition of 'struct mmu_psize_def'
arch/powerpc/include/asm/mmu-hash64.h:159: error: expected identifier or '(' before numeric constant
arch/powerpc/include/asm/mmu-hash64.h:396: error: conflicting types for 'mm_context_t'
arch/powerpc/include/asm/mmu-book3e.h:184: error: previous declaration of 'mm_context_t' was here
cc1: warnings being treated as errors
arch/powerpc/kernel/pci_64.c: In function 'pcibios_unmap_io_space':
arch/powerpc/kernel/pci_64.c💯 error: unused variable 'res'
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The two versions are doing almost exactly the same thing. No need to
maintain them as separate files. This patch also has the side effect
of making the PCI device tree scanning code available to 32 bit powerpc
machines, but no board ports actually make use of this feature at this
point.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The PCI device tree scanning code in pci_64.c is some useful functionality.
It allows PCI devices to be described in the device tree instead of being
probed for, which in turn allows pci devices to use all of the device tree
facilities to describe complex PCI bus architectures like GPIO and IRQ
routing (perhaps not a common situation for desktop or server systems,
but useful for embedded systems with on-board PCI devices).
This patch moves the device tree scanning into pci-common.c so it is
available for 32-bit powerpc machines too.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
resource_size_t is 64 bits on PowerPC 64.
Gets rid of this warning:
arch/powerpc/kernel/pci_64.c: In function 'pcibios_map_io_space':
arch/powerpc/kernel/pci_64.c:504: warning: format '%016lx' expects type 'long unsigned int', but argument 2 has type 'resource_size_t'
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is a random collection of added ifdef's around portions of
code that only mak sense on server processors. Using either
CONFIG_PPC_STD_MMU_64 or CONFIG_PPC_BOOK3S as seems appropriate.
This is meant to make the future merging of Book3E 64-bit support
easier.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The pcnet32 driver has had in its device id table for some time a match
against the "broken" vendor ID. No need to fake out the vendor ID
with an explicit fixup.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
A couple of issues crept in since about 2.6.27 related to accessing PCI
device ROMs on various powerpc machines.
First, historically, we don't allocate the ROM resource in the resource
tree. I'm not entirely certain of why, I susepct they often contained
garbage on x86 but it's hard to tell. This causes the current generic
code to always call pci_assign_resource() when trying to access the said
ROM from sysfs, which will try to re-assign some new address regardless
of what the ROM BAR was already set to at boot time. This can be a
problem on hypervisor platforms like pSeries where we aren't supposed
to move PCI devices around (and in fact probably can't).
Second, our code that generates the PCI tree from the OF device-tree
(instead of doing config space probing) which we mostly use on pseries
at the moment, didn't set the (new) flag IORESOURCE_SIZEALIGN on any
resource. That means that any attempt at re-assigning such a resource
with pci_assign_resource() would fail due to resource_alignment()
returning 0.
This fixes this by doing these two things:
- The code that calculates resource flags based on the OF device-node
is improved to set IORESOURCE_SIZEALIGN on any valid BAR, and while at
it also set IORESOURCE_READONLY for ROMs since we were lacking that too
- We now allocate ROM resources as part of the resource tree. However
to limit the chances of nasty conflicts due to busted firmwares, we
only do it on the second pass of our two-passes allocation scheme,
so that all valid and enabled BARs get precedence.
This brings pSeries back the ability to access PCI ROMs via sysfs (and
thus initialize various video cards from X etc...).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
move the definition of hose_list next to its hotplug spinlock.
create pcibios_io_size to encapsulate ifdef in existing pci-common
function pcibios_vaddr_is_ioport
move pci_address_to_pio to pci-common, using new pcibios_io_size, and
protect this GPL exported function against concurrent hotplug removal
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
X has been failing to start on my quad G5 powermac since commit
1fd0f52583 ("powerpc: Fix domain numbers
in /proc on 64-bit") went in. The reason is that the change allows X
to see the PCI-PCI bridge above the video card (previously it was
obscured by the fact that there were two "00" directories in
/proc/bus/pci), and the pciconfig_iobase system call on the bridge is
failing because of a hack that we have to return information about the
AGP bus when X asks about bus 0. This machine doesn't have an AGP bus
(it has PCI Express) and so the pciconfig_iobase call is returning -1,
which ultimately causes X to fail to start.
This fixes it by checking that we have an AGP bridge before
redirecting the pciconfig_iobase call to return information about the
AGP bus. With this, X starts successfully both on a quad G5 with
PCI Express and on an older dual G5 with AGP.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently, our PCI code uses the pcibios_fixup_bus() callback, which
is called by the generic code when probing PCI buses, for two
different things.
One is to set up things related to the bus itself, such as reading
bridge resources for P2P bridges, fixing them up, or setting up the
iommu's associated with bridges on some platforms.
The other is some setup for each individual device under that bridge,
mostly setting up DMA mappings and interrupts.
The problem is that this approach doesn't work well with PCI hotplug
when an existing bus is re-probed for new children. We fix this
problem by splitting pcibios_fixup_bus into two routines:
pcibios_setup_bus_self() is now called to setup the bus itself
pcibios_setup_bus_devices() is now called to setup devices
pcibios_fixup_bus() is then modified to call these two after reading the
bridge bases, and the OF based PCI probe is modified to avoid calling
into the first one when rescanning an existing bridge.
[paulus@samba.org - fixed eeh.h for 32-bit compile now that pci-common.c
is including it unconditionally.]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The function pcibios_do_bus_setup() was used by pcibios_fixup_bus()
to perform setup that is different between the 32-bit and 64-bit
code. This difference no longer exists, thus the function is removed
and the setup now done directly from pci-common.c.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The 32-bit and 64-bit powerpc PCI code used to set up the resource
pointers of the root bus of a given PHB in completely different
places.
This unifies this in large part, by making 32-bit use a routine very
similar to what 64-bit does when initially scanning the PCI busses.
The actual setup of the PHB resources itself is then moved to a
common function in pci-common.c.
This should cause no functional change on 64-bit. On 32-bit, the
effect is that the PHB resources are going to be setup a bit earlier,
instead of being setup from pcibios_fixup_bus().
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This removes the various DBG() macro from the powerpc PCI code and
makes it use the standard pr_debug instead.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The code to properly expose domain numbers in /proc is somewhat
bogus on ppc64 as it depends on the "buid" field being non-0,
but that field is really pseries specific.
This removes that code and makes ppc64 use the same code as 32-bit
which effectively decides whether to expose domains based on
ppc_pci_flags set by the platform, and sets the default for 64-bit
to enable domains and enable compatibility for domain 0 (which
strips the domain number for domain 0 to help with X servers).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
A typo/thinko made us pass the wrong argument to __flush_hash_table_range
when unplugging bridges, thus not flushing all the translations for
the IO space on unplug. The third parameter to __flush_hash_table_range
is `end', not `size'.
This causes the hypervisor to refuse unplugging slots.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We essentially adopt the 64-bit dma code, with some changes to support
32-bit systems, including HIGHMEM. dma functions on 32-bit are now
invoked via accessor functions which call the correct op for a device based
on archdata dma_ops. If there is no archdata dma_ops, this defaults
to dma_direct_ops.
In addition, the dma_map/unmap_page functions are added to dma_ops
because we can't just fall back on map/unmap_single when HIGHMEM is
enabled. In the case of dma_direct_*, we stop using map/unmap_single
and just use the page version - this saves a lot of ugly
ifdeffing. We leave map/unmap_single in the dma_ops definition,
though, because they are needed by the iommu code, which does not
implement map/unmap_page. Ideally, going forward, we will completely
eliminate map/unmap_single and just have map/unmap_page, if it's
workable for 64-bit.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Use the struct device's numa_node instead; use accessor functions
to get/set numa_node.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
During the next merge window, pci_name()'s return value will become
const, so use the new dev_set_name() instead to avoid the warning (from
linux-next):
arch/powerpc/kernel/pci_64.c: In function 'of_create_pci_dev':
arch/powerpc/kernel/pci_64.c:193: warning: passing argument 1 of 'sprintf' discards qualifiers from pointer target type
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We must always hookup the pci_bus resource 0 to the PHB io_resource
even if the latter is empty (the bus has no IO support). Otherwise,
some other code will end up hooking it up to something bogus and the
resource tree will end up being broken.
This fixes boot on QS20 Cell blades where the IDE driver failed to
allocate the IO resources due to breakage of the resource tree.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This merge the two implementations, based on the previously
fixed up 32 bits one. The pcibios_enable_device_hook in ppc_md
is now available for ppc64 use. Also remove the new unused
"initial" parameter from it and fixup users.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The way iSeries manages PCI IO and Memory resources is a bit strange
and is based on overriding the content of those resources with home
cooked ones afterward.
This changes it a bit to better integrate with the new resource handling
so that the "virtual" tokens that iSeries replaces resources with are
done from the proper per-device fixup hook, and bridge resources are
set to enclose that token space. This fixes various things such as
the output of /proc/iomem & ioports, among others. This also fixes up
various boot messages as well.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The 32 bits PCI code now uses the generic code for assigning unassigned
resources and an algorithm similar to x86 for claiming existing ones.
This works far better than the 64 bits code which basically can only
claim existing ones (pci_probe_only=1) or would fall apart completely.
This merges them so that the new 32 bits implementation is used for both.
64 bits now gets the new PCI flags for controlling the behaviour, though
the old pci_probe_only global is still there for now to be cleared if you
want to.
I kept a pcibios_claim_one_bus() function mostly based on the old 64
bits code for use by the DLPAR hotplug. This will have to be cleaned
up, thought I hope it will work in the meantime.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The PCI code in 32 and 64 bits fixes up resources differently.
32 bits uses a header quirk plus handles bridges in pcibios_fixup_bus()
while 64 bits does things in various places depending on whether you
are using OF probing, using PCI hotplug, etc...
This merges those by basically using the 32 bits approach for both,
with various tweaks to make 64 bits work with the new approach.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This merges the PowerPC 32 and 64 bits version of pcibios_resource_to_bus
and pcibios_bus_to_resource().
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds flags the platforms can use to enable domain numbers
in /proc/bus/pci.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adds to the 32 bits PCI code some flags, replacing the old
pci_assign_all_busses global, that allow us to control various
aspects of the PCI probing, such as whether to re-assign all
resources or not, or to not try to assign anything at all.
This also adds the flag x86 already has to avoid ISA alignment
on bridges that don't have ISA forwarding enabled (no legacy
devices on the top level bus) and sets it for PowerMacs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
PowerPC currently doesn't implement pci_set_dma_mask(), which means drivers
calling it will get the generic version in drivers/pci/pci.c.
The powerpc dma mapping ops include a dma_set_mask() hook, which luckily is
not implemented by anyone - so there is no bug in the fact that the hook
is currently never called.
However in future we'll add implementation(s) of dma_set_mask(), and so we
need pci_set_dma_mask() to call the hook.
To save adding a hook to the dma mapping ops, pci-set_consistent_dma_mask()
simply calls the dma_set_mask() hook and then copies the new mask into
dev.coherenet_dma_mask.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This merges the 32-bit and 64-bit implementations of
pci_process_bridge_OF_ranges(). The new function is cleaner than both
the old ones, and supports 64 bits ranges on ppc32 which is necessary
for the 4xx port.
It also adds some better (hopefully) output to the kernel log which
should help diagnose problems and makes better use of existing OF
parsing helpers (avoiding a few bugs of both implementations along
the way).
There are still a few unfortunate ifdef's but there is no way around
these for now at least not until some other bits of the PCI code are
made common.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The /proc/bus/pci/* files list PCI domain numbers only for
devices that claim to be on a multi-domain system. The check
for this is broken on powerpc, because the buid value is
truncated to 32 bits.
There is at least one machine (IBM QS21) that only uses
the high-order bits of the buid, so the return value
of pci_proc_domain() ends up being always zero, which
makes /proc/bus/pci useless.
Change the logic to always return '1' for a nonzero
buid value.
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
powerpc has a couple of bugs in the usage of dma_masks that tend to
break when drivers explicitly try to set a 32-bit mask for example.
First, the code that generates the pci devices from the OF device-tree
doesn't initialize the mask properly, then our implementation of
set_dma_mask() was trying to validate the -previous- mask value, not the
one passed in as an argument.
This fixes these problems.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (209 commits)
[POWERPC] Create add_rtc() function to enable the RTC CMOS driver
[POWERPC] Add H_ILLAN_ATTRIBUTES hcall number
[POWERPC] xilinxfb: Parameterize xilinxfb platform device registration
[POWERPC] Oprofile support for Power 5++
[POWERPC] Enable arbitary speed tty ioctls and split input/output speed
[POWERPC] Make drivers/char/hvc_console.c:khvcd() static
[POWERPC] Remove dead code for preventing pread() and pwrite() calls
[POWERPC] Remove unnecessary #undef printk from prom.c
[POWERPC] Fix typo in Ebony default DTS
[POWERPC] Check for NULL ppc_md.init_IRQ() before calling
[POWERPC] Remove extra return statement
[POWERPC] pasemi: Don't auto-select CONFIG_EMBEDDED
[POWERPC] pasemi: Rename platform
[POWERPC] arch/powerpc/kernel/sysfs.c: Move NUMA exports
[POWERPC] Add __read_mostly support for powerpc
[POWERPC] Modify sched_clock() to make CONFIG_PRINTK_TIME more sane
[POWERPC] Create a dummy zImage if no valid platform has been selected
[POWERPC] PS3: Bootwrapper support.
[POWERPC] powermac i2c: Use mutex
[POWERPC] Schedule removal of arch/ppc
...
Fixed up conflicts manually in:
Documentation/feature-removal-schedule.txt
arch/powerpc/kernel/pci_32.c
arch/powerpc/kernel/pci_64.c
include/asm-powerpc/pci.h
and asked the powerpc people to double-check the result..
Currently there are 97 occurrences where drivers need the pci
revision ID. We can do this once for all devices. Even the pci
subsystem needs the revision several times for quirks. The extra
u8 member pads out nicely in the pci_dev struct.
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently pcibios_add_platform_entries() returns void, but could fail,
so instead have it return an int and propagate errors up to
pci_create_sysfs_dev_files().
Fixes:
arch/powerpc/kernel/pci_64.c: In function 'pcibios_add_platform_entries':
arch/powerpc/kernel/pci_64.c:878: warning: ignoring return value of
'device_create_file', declared with attribute warn_unused_result
arch/powerpc/kernel/pci_32.c: In function 'pcibios_add_platform_entries':
arch/powerpc/kernel/pci_32.c:1043: warning: ignoring return value of
'device_create_file', declared with attribute warn_unused_result
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove uses of hack GET_64BIT() property macro and use
the more general of_read_number() function from prom.h
as suggested by Milton.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Use the ppc64 style list management and allocation functions for
pci_controllers. This makes the pci_controller structs just a bit more
common between ppc32 & ppc64.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Moved the low hanging fruit that was either identical or close
to it between ppc32 & ppc64 for PCI into pci-common.c
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Make the pci_controller struct use global_number for the PHB domain number
instead of index to match what ppc64 does and reuse its pci_domain_nr code.
Introduced a pci-common.c to handle shared code between ppc32 & ppc64.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Commit 3d5134ee83 left debugging turned on
in arch/powerpc/kernel/pci_64.c. This turns it off again.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This rewrites pretty much from scratch the handling of MMIO and PIO
space allocations on powerpc64. The main goals are:
- Get rid of imalloc and use more common code where possible
- Simplify the current mess so that PIO space is allocated and
mapped in a single place for PCI bridges
- Handle allocation constraints of PIO for all bridges including
hot plugged ones within the 2GB space reserved for IO ports,
so that devices on hotplugged busses will now work with drivers
that assume IO ports fit in an int.
- Cleanup and separate tracking of the ISA space in the reserved
low 64K of IO space. No ISA -> Nothing mapped there.
I booted a cell blade with IDE on PIO and MMIO and a dual G5 so
far, that's it :-)
With this patch, all allocations are done using the code in
mm/vmalloc.c, though we use the low level __get_vm_area with
explicit start/stop constraints in order to manage separate
areas for vmalloc/vmap, ioremap, and PCI IOs.
This greatly simplifies a lot of things, as you can see in the
diffstat of that patch :-)
A new pair of functions pcibios_map/unmap_io_space() now replace
all of the previous code that used to manipulate PCI IOs space.
The allocation is done at mapping time, which is now called from
scan_phb's, just before the devices are probed (instead of after,
which is by itself a bug fix). The only other caller is the PCI
hotplug code for hot adding PCI-PCI bridges (slots).
imalloc is gone, as is the "sub-allocation" thing, but I do beleive
that hotplug should still work in the sense that the space allocation
is always done by the PHB, but if you unmap a child bus of this PHB
(which seems to be possible), then the code should properly tear
down all the HPTE mappings for that area of the PHB allocated IO space.
I now always reserve the first 64K of IO space for the bridge with
the ISA bus on it. I have moved the code for tracking ISA in a separate
file which should also make it smarter if we ever are capable of
hot unplugging or re-plugging an ISA bridge.
This should have a side effect on platforms like powermac where VGA IOs
will no longer work. This is done on purpose though as they would have
worked semi-randomly before. The idea at this point is to isolate drivers
that might need to access those and fix them by providing a proper
function to obtain an offset to the legacy IOs of a given bus.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This changes the way of_platform_pci creates PCI host bridges such
that it uses request_phb_iospace() for mapping the IO ports, instead
of using the dynamic hotplug stuff. That guarantees the IO space
stays within the 2GB limit and thus doesn't break half of the legacy
drivers around.
Fixes a couple of warnings due to missing IO space while at it.
This patch is a temporary workaround for 2.6.22 before a more complete
rewrite of IO mappings is merged in 2.6.23
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
My patch "Cope with PCI host bridge I/O window not starting at 0"
introduced a bug in the calculation of the virtual addresses for the
I/O windows of PCI host bridges other than the first, because it
didn't account for the fact that hose->io_resource gets offset so that
it reflects the range of global I/O port numbers assigned to the
bridge. This fixes it and simplifies get_bus_io_range() in the
process.
Signed-off-by: Paul Mackerras <paulus@samba.org>