pci_config_lock must be a real spinlock in preempt-rt. Convert it to
raw_spinlock. No change for !RT kernels.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This patch adds a probing code that seeks for an specific pci bus. It
still needs testing, but it is hoped that this will help to identify the
memory controller with Xeon 55xx series.
Signed-off-by: NAristeu Sergio <arozansk@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Replace the #ifdef'ed OLPC-specific init functions by a conditional
x86_init function.  If the function returns 0 we leave pci_arch_init,
otherwise we continue.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Andres Salomon <dilinger@collabora.co.uk>
LKML-Reference: <43F901BD926A4E43B106BF17856F0755A318CE89@orsmsx508.amr.corp.intel.com>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The main benefit of using ACPI host bridge window information is that
we can do better resource allocation in systems with multiple host bridges,
e.g., http://bugzilla.kernel.org/show_bug.cgi?id=14183

Sometimes we need _CRS information even if we only have one host bridge,
e.g., https://bugs.launchpad.net/ubuntu/+source/linux/+bug/341681

Most of these systems are relatively new, so this patch turns on
"pci=use_crs" only on machines with a BIOS date of 2008 or newer.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Platforms like Moorestown want to override the pcibios_fixup_irqs
default function. Add it to x86_init.pci.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D00@orsmsx508.amr.corp.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Moorestown wants to reuse pcibios_init_irq but needs to provide its
own implementation of pci_enable_irq. After we distangled the init we
can move the init_irq call to x86_init and remove the pci_enable_irq
!= NULL check in pcibios_init_irq. pci_enable_irq is compile time
initialized to pirq_enable_irq and the special cases which override it
(visws and acpi) set the x86_init function pointer to noop. That
allows MSRT to override pci_enable_irq and otherwise run
pcibios_init_irq unmodified.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80CFF@orsmsx508.amr.corp.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

The PCI initialization in pci_subsys_init() is a mess. pci_numaq_init,
pci_acpi_init, pci_visws_init and pci_legacy_init are called and each
implementation checks and eventually modifies the global variable
pcibios_scanned.

x86_init functions allow us to do this more elegant. The pci.init
function pointer is preset to pci_legacy_init. numaq, acpi and visws
can modify the pointer in their early setup functions. The functions
return 0 when they did the full initialization including bus scan. A
non zero return value indicates that pci_legacy_init needs to be
called either because the selected function failed or wants the
generic bus scan in pci_legacy_init to happen (e.g. visws).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80CFE@orsmsx508.amr.corp.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

This patch factors out the search for an MMCONFIG region, which was
previously implemented in both mmconfig_32 and mmconfig_64.  No functional
change.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This changes pci_mmcfg_region from a table to a list, to make it easier
to add and remove MMCONFIG regions for PCI host bridge hotplug.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The virtual address is only used for x86_64, but it's so much simpler
to manage it as part of the pci_mmcfg_region that I think it's worth
wasting a pointer per MMCONFIG region on x86_32.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This patch adds a resource and corresponding name to the MMCONFIG
structure.  This makes allocation simpler (we can allocate the
resource and name at the same time we allocate the pci_mmcfg_region),
and gives us a way to hang onto the resource after inserting it.
This will be needed so we can release and free it when hot-removing
a host bridge.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This only renames the struct pci_mmcfg_region members; no functional change.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This adds a struct pci_mmcfg_region with a little more information
than the struct acpi_mcfg_allocation used previously.  The acpi_mcfg
structure is defined by the spec, so we can't change it.

To begin with, struct pci_mmcfg_region is basically the same as the
ACPI MCFG version, but future patches will add more information.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This factors out the common "bus << 20" expression used when computing the
MMCONFIG address.
Reviewed-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This reverts commit 9e9f46c4.

Quoting from the commit message:

 "At this point, it seems to solve more problems than it causes, so let's
  try using it by default.  It's an easy revert if it ends up causing
  trouble."

And guess what? The _CRS code causes trouble.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move
arch/x86/kernel/acpi/boot.c: acpi_parse_mcfg()
to
arch/x86/pci/mmconfig-shared.c: pci_parse_mcfg()
where it is used, and make it static.

Move associated globals and helper routine with it.

No functional change.

This code move is in preparation for SFI support,
which will allow the PCI code to find the MCFG table
on systems which do not support ACPI.
Signed-off-by: NLen Brown <len.brown@intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>

At this point, it seems to solve more problems than it causes, so let's try using it by default.  It's an easy revert if it ends up causing trouble.
Reviewed-by: NYinghai Lu <yhlu.kernel@gmail.com>
Acked-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Impact: cleanup

Now that arch/x86/pci/pci.h is used in a number of other places as well,
move the lowlevel x86 pci definitions into the architecture include files.
(not to be confused with the existing arch/x86/include/asm/pci.h file,
which provides public details about x86 PCI)

Tested on: X86_32_UP, X86_32_SMP and X86_64_SMP
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: Changes reboot behavior.

If port CF9 seems to be safe to touch, attempt it before trying the
keyboard controller.  Port CF9 is not available on all chipsets (a
significant but decreasing number of modern chipsets don't implement
it), but port CF9 itself should in general be safe to poke (no ill
effects if unimplemented) on any system which has PCI Configuration
Method #1 or #2, as it falls inside the PCI configuration port range
in both cases.  No chipset without PCI is known to have port CF9,
either, although an explicit "pci=bios" would mean we miss this and
therefore don't use port CF9.  An explicit "reboot=pci" can be used to
force the use of port CF9.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

I don't know, if this new code boots, but at least it
compiles. Someone should really test it.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Patch d49c4288 (tip/x86/mpparse) introduced some changes in calling
subsys_init calls if CONFIG_X86_NUMAQ option is set. This patch
updates subsystem initalization according to this changes.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

So far subsys_initcalls has been executed in this order depending on
the object order in the Makefile:

arch/x86/pci/visws.c:subsys_initcall(pcibios_init);
arch/x86/pci/numa.c:subsys_initcall(pci_numa_init);
arch/x86/pci/acpi.c:subsys_initcall(pci_acpi_init);
arch/x86/pci/legacy.c:subsys_initcall(pci_legacy_init);
arch/x86/pci/irq.c:subsys_initcall(pcibios_irq_init);
arch/x86/pci/common.c:subsys_initcall(pcibios_init);

This patch removes the ordering dependency. There is now only one
subsys_initcall function that contains subsystem initialization code
with a defined order.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

"Form follows function". Code is now where it belongs to.
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Contention for scarce PCI memory resources has been growing
due to an increasing number of PCI slots in large multi-node
systems.  The kernel currently attempts by default to
allocate memory for all PCI expansion ROMs so there has
also been an increasing number of PCI memory allocation
failures seen on these systems.  This occurs because the
BIOS either (1) provides insufficient PCI memory resource
for all the expansion ROMs or (2) provides adequate PCI
memory resource for expansion ROMs but provides the
space in kernel unexpected BIOS assigned P2P non-prefetch
windows.

The resulting PCI memory allocation failures may be benign
when related to memory requests for expansion ROMs themselves
but in some cases they can occur when attempting to allocate
space for more critical BARs.  This can happen when a successful
expansion ROM allocation request consumes memory resource
that was intended for a non-ROM BAR.  We have seen this
happen during PCI hotplug of an adapter that contains a
P2P bridge where successful memory allocation for an
expansion ROM BAR on device behind the bridge consumed
memory that was intended for a non-ROM BAR on the P2P bridge.
In all cases the allocation failure messages can be very
confusing for users.

This patch provides a new 'pci=norom' kernel boot parameter
that can be used to disable the default PCI expansion ROM memory
resource allocation.  This provides a way to avoid the above
described issues on systems that do not contain PCI devices
for which drivers or user-level applications depend on the
default PCI expansion ROM memory resource allocation behavior.
Signed-off-by: NGary Hade <garyhade@us.ibm.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Previously, one would have to specifically choose CONFIG_OLPC and
CONFIG_PCI_GOOLPC in order to enable PCI_OLPC.  That doesn't really work
for distro kernels, so this patch allows one to choose CONFIG_OLPC and
CONFIG_PCI_GOANY in order to build in OLPC support in a generic kernel (as
requested by Robert Millan).

This also moves GOOLPC before GOANY in the menuconfig list.

Finally, make pci_access_init return early if we detect OLPC hardware.
There's no need to continue probing stuff, and pci_pcbios_init
specifically trashes our settings (we didn't run into that before because
PCI_GOANY wasn't supported).
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

this change:

| commit 08f1c192
| Author: Muli Ben-Yehuda <muli@il.ibm.com>
| Date:   Sun Jul 22 00:23:39 2007 +0300
|
|    x86-64: introduce struct pci_sysdata to facilitate sharing of ->sysdata
|
|    This patch introduces struct pci_sysdata to x86 and x86-64, and
|    converts the existing two users (NUMA, Calgary) to use it.
|
|    This lays the groundwork for having other users of sysdata, such as
|    the PCI domains work.
|
|    The Calgary bits are tested, the NUMA bits just look ok.

replaces pcibios_scan_root with pci_scan_bus_parented...

but in pcibios_scan_root we have a DMI check:

    dmi_check_system(pciprobe_dmi_table);

when when have several peer root buses this could be called multiple
times (which is bad), so move that call to pci_access_init().
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

so we don't align the io port start address for pci cards.

also move out dmi check out acpi.c, because it has nothing to do with acpi.
it could spare some calling when we have several peer root buses.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This adds support for OLPC XO hardware.  Open Firmware on XOs don't contain
the VSA, so it is necessary to emulate the PCI BARs in the kernel.  This also
adds functionality for running EC commands, and a CONFIG_OLPC.

A number of OLPC drivers depend upon CONFIG_OLPC.

olpc_ec_timeout is a hack to work around Embedded Controller bugs.

[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: geode_has_vsa build fix]
[akpm@linux-foundation.org: olpc_register_battery_callback doesn't exist]
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

so will disable that feature by default, and only enable that via
pci=check_enable_amd_mmconf or for system match with dmi table.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

For x86_64, need to free pci_mmcfg_virt, and iounmap some pointers
when MMCONF is not reserved in E820 or acpi _CRS and get rejected.
Signed-off-by: NYinghai Lu <yinghai.lu@sun.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Greg KH <greg@kroah.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This path adds validation of the MMCONFIG table against the ACPI reserved
motherboard resources.  If the MMCONFIG table is found to be reserved in
ACPI, we don't bother checking the E820 table.  The PCI Express firmware
spec apparently tells BIOS developers that reservation in ACPI is required
and E820 reservation is optional, so checking against ACPI first makes
sense.  Many BIOSes don't reserve the MMCONFIG region in E820 even though
it is perfectly functional, the existing check needlessly disables MMCONFIG
in these cases.

In order to do this, MMCONFIG setup has been split into two phases.  If PCI
configuration type 1 is not available then MMCONFIG is enabled early as
before.  Otherwise, it is enabled later after the ACPI interpreter is
enabled, since we need to be able to execute control methods in order to
check the ACPI reserved resources.  Presently this is just triggered off
the end of ACPI interpreter initialization.

There are a few other behavioral changes here:

- Validate all MMCONFIG configurations provided, not just the first one.

- Validate the entire required length of each configuration according to
  the provided ending bus number is reserved, not just the minimum required
  allocation.

- Validate that the area is reserved even if we read it from the chipset
  directly and not from the MCFG table.  This catches the case where the
  BIOS didn't set the location properly in the chipset and has mapped it
  over other things it shouldn't have.

This also cleans up the MMCONFIG initialization functions so that they
simply do nothing if MMCONFIG is not compiled in.

Based on an original patch by Rajesh Shah from Intel.

[akpm@linux-foundation.org: many fixes and cleanups]
Signed-off-by: NRobert Hancock <hancockr@shaw.ca>
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NAndi Kleen <ak@suse.de>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use the generic pci_enable_resources() instead of the arch-specific code.

Unlike this arch-specific code, the generic version:
    - checks for resource collisions with "!r->parent"
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We currently keep 2 lists of PCI devices in the system, one in the
driver core, and one all on its own.  This second list is sorted at boot
time, in "BIOS" order, to try to remain compatible with older kernels
(2.2 and earlier days).  There was also a "nosort" option to turn this
sorting off, to remain compatible with even older kernel versions, but
that just ends up being what we have been doing from 2.5 days...

Unfortunately, the second list of devices is not really ever used to 
determine the probing order of PCI devices or drivers[1].  That is done
using the driver core list instead.  This change happened back in the
early 2.5 days.

Relying on BIOS ording for the binding of drivers to specific device
names is problematic for many reasons, and userspace tools like udev
exist to properly name devices in a persistant manner if that is needed,
no reliance on the BIOS is needed.

Matt Domsch and others at Dell noticed this back in 2006, and added a
boot option to sort the PCI device lists (both of them) in a
breadth-first manner to help remain compatible with the 2.4 order, if
needed for any reason.  This option is not going away, as some systems
rely on them.

This patch removes the sorting of the internal PCI device list in "BIOS"
mode, as it's not needed at all anymore, and hasn't for many years.
I've also removed the PCI flags for this from some other arches that for
some reason defined them, but never used them.

This should not change the ordering of any drivers or device probing.

[1] The old-style pci_get_device and pci_find_device() still used this
sorting order, but there are very few drivers that use these functions,
as they are deprecated for use in this manner.  If for some reason, a
driver rely on the order and uses these functions, the breadth-first
boot option will resolve any problem.

Cc: Matt Domsch <Matt_Domsch@dell.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We want to allow different implementations of pci_raw_ops for standard
and extended config space on x86.  Rather than clutter generic code with
knowledge of this, we make pci_raw_ops private to x86 and use it to
implement the new raw interface -- raw_pci_read() and raw_pci_write().
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Thanks to Loic Prylli <loic@myri.com>, who originally proposed
this idea.

Always using legacy configuration mechanism for the legacy config space
and extended mechanism (mmconf) for the extended config space is
a simple and very logical approach. It's supposed to resolve all
known mmconf problems. It still allows per-device quirks (tweaking
dev->cfg_size). It also allows to get rid of mmconf fallback code.
Signed-off-by: NIvan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use _CRS for PCI resource allocation

This patch resolves an issue where incorrect PCI memory and i/o ranges
are being assigned to hotplugged PCI devices on some IBM systems.  The
resource mis-allocation not only makes the PCI device unuseable but
often makes the entire system unuseable due to resulting machine checks.

The hotplug capable PCI slots on the affected systems are not located
under a standard P2P bridge but are instead located under PCI root
bridges or subtractive decode P2P bridges.  For example, the IBM x3850
contains 2 hotplug capable PCI-X slots and 4 hotplug capable PCIe slots
with the PCI-X slots each located under a PCI root bridge and the PCIe
slots each located under a subtractive decode P2P bridge.

The current i386/x86_64 PCI resource allocation code does not use _CRS
returned resource information.  No other resource information source is
available for slots that are not below a standard P2P bridge so
incorrect ranges are being allocated from e820 hole causing the bad
result.

This patch causes the kernel to use _CRS returned resource info.  It is
roughly based on a change provided by Matthew Wilcox for the ia64 kernel
in 2005.  Due to possible buggy BIOS factor and possible yet to be
discovered kernel issues the function is disabled by default and can be
enabled with pci=use_crs.
Signed-off-by: NGary Hade <gary.hade@us.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Skip ISA ioresource alignment on some systems

To conserve limited PCI i/o resource on some IBM multi-node systems, the
BIOS allocates (via _CRS) and expects the kernel to use addresses in
ranges currently excluded by pcibios_align_resource() [i386/pci/i386.c].
This change allows the kernel to use the currently excluded address
ranges on the IBM x3800, x3850, and x3950.
Signed-off-by: NGary Hade <gary.hade@us.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Some broken devices have been discovered to require %al/%ax/%eax registers
for MMIO config space accesses.  Modify mmconfig.c to use these registers
explicitly (rather than modify the global readb/writeb/etc inlines).

AK: also changed i386 to always use eax
AK: moved change to extended space probing to different patch
AK: reworked with inlines according to Linus' requirements.
AK: improve comments.
Signed-off-by: Ndean gaudet <dean@arctic.org>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>