Need to probe slave device first to make it release PDIAG-
(this is required for correct device side cable detection).

Based on libata commit f31f0cc2.

Thanks to Craig for testing this patch.

Cc: Craig Block <chblock3@yahoo.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Convert {ide_hwif_t,ide_pci_device_t}->host_flag to be u16.

* Add IDE_HFLAG_POST_SET_MODE host flag to indicate the need to program 
  the host for the transfer mode after programming the device.  Set it
  in au1xxx-ide, amd74xx, cs5530, cs5535, pdc202xx_new, sc1200, pmac
  and via82cxxx host drivers.

* Add IDE_HFLAG_NO_SET_MODE host flag to indicate the need to completely
  skip programming of host/device for the transfer mode ("smart" hosts).
  Set it in it821x host driver and check it in ide_tune_dma().

* Add ide_set_pio_mode()/ide_set_dma_mode() helpers and convert all
  direct ->set_pio_mode/->speedproc users to use these helpers.

* Move ide_config_drive_speed() calls from ->set_pio_mode/->speedproc
  methods to callers.

* Rename ->speedproc method to ->set_dma_mode, make it void and update
  all implementations accordingly.

* Update ide_set_xfer_rate() comments.

* Unexport ide_config_drive_speed().

v2:
* Fix issues noticed by Sergei:
  - export ide_set_dma_mode() instead of moving ->set_pio_mode abuse wrt
    to setting DMA modes from sc1200_set_pio_mode() to do_special()
  - check IDE_HFLAG_NO_SET_MODE in ide_tune_dma()
  - check for (hwif->set_pio_mode) == NULL in ide_set_pio_mode()
  - check for (hwif->set_dma_mode) == NULL in ide_set_dma_mode()
  - return -1 from ide_set_{pio,dma}_mode() if ->set_{pio,dma}_mode == NULL
  - don't set ->set_{pio,dma}_mode on it821x in "smart" mode
  - fix build problem in pmac.c
  - minor fixes in au1xxx-ide.c/cs5530.c/siimage.c
  - improve patch description

Changes in behavior caused by this patch:
- HDIO_SET_PIO_MODE ioctl would now return -ENOSYS for attempts to change
  PIO mode if it821x controller is in "smart" mode
- removal of two debugging printk-s (from cs5530.c and sc1200.c)
- transfer modes 0x00-0x07 passed from user space may be programmed twice on
  the device (not really an issue since 0x00 is not supported correctly by
  any host driver ATM, 0x01 is not supported at all and 0x02-0x07 are invalid)
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Check ide_config_drive_speed() return value.

* While at also call ide_config_drive_speed() if the transfer mode is
  XFER_PIO_SLOW (this case happens iff the transfer mode has already been
  set on the device by ide-proc.c::set_xfer_rate()) and remove redundant
  setting of ->{init,current}_speed.

* Bump driver version.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Set transfer mode on the device before programming the host controller for
the new timings (matches what auide_tune_chipset() is doing wrt DMA modes).
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add "good DMA drives" hack for icside to ide-dma.c::ide_find_dma_mode()
  (in the long-term it should be either removed or generalized for all hosts).

* Use ide_tune_dma() in icside.c::icside_dma_check().

  This results in the following changes in behavior:
  - pre-EIDE SWDMA modes are now also respected
  - drive->autodma is checked instead of hwif->autodma
    (doesn't really matter as icside sets both to "1")

* Make ide-dma.c::__ide_dma_good_drive() static and drop "__" prefix.

Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add missing initialization of hwif->autodma and drive->autodma to
  pmac_ide_setup_dma().

* Use ide_tune_dma() in pmac_ide_dma_check().

While at it:

* Fix pmac_ide_dma_check() return value if DMA mode is not programmed
  (should be "-1" otherwise ide_set_dma() will try to enable DMA).

* Remove unnecessary drive->using_dma fiddling (->dma_off_quietly is always
  called before ide_set_dma() call and ide_set_dma() calls ->ide_dma_on if
  ->ide_dma_check returns "0").

v2:
* No reason to blacklist all ide_floppy devices and the old code was always
  enabling DMA anyway (without even programming controller/device if the
  device was ide_floppy).

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Use ide_config_drive_speed() instead of pmac_ide_do_setfeature() and remove
the latter, also  ide-iops.c::__ide_wait_stat() could be static again.

Since for IDE PMAC host driver IDE_CONTROL_REG is always true, device's
->quirk_list is always zero and ->ide_dma_host_{on,off} are nops than
the only changes in behavior are:

* if PIO mode is set then ->dma_off_queitly is called to disable DMA

* if setting transfer mode fails ide_dump_status() is called to dump status

v2:
* IDE PMAC controllers allow separate PIO and DMA timings and PPC userland
  depends on this fact, and calls "hdparm -p" without calling "hdparm -d".

  Therefore to compensate for DMA being disabled by ide_config_drive_speed()
  for PIO modes:

  - add IDE_HFLAG_SET_PIO_MODE_KEEP_DMA flag and set it in PMAC host driver

  - add handling of the new flag to ide-io.c::do_special()

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Upper layers are responsible for controlling nIEN so don't clear nIEN after
command execution in pmac_ide_do_setfeature().

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Use __ide_wait_stat() instead of wait_for_ready() in pmac_ide_do_setfeature().

While at it do following changes to match __ide_wait_stat() call in
ide_config_drive_speed():

* Wait WAIT_CMD time (20 sec) instead of 2 sec for device to clear BUSY_STAT.

* Check DRQ_STAT bit (shouldn't be set for good device status).

Also remove no longer needed wait_for_ready() from ide-iops.c.
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Don't check for good device status before executing the command in
pmac_ide_do_setfeature() (ide_config_drive_speed() doesn't do this).

It is a job of upper layers to guarantee that the device is ready to
accept new command before we get here.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Split off checking of the status register from ide_wait_stat() to
  __ide_wait_stat() helper.

* Use the new helper in ide_config_drive_speed().  The only change in the
  functionality is that the function now fails if after 20 sec (WAIT_CMD)
  device is still busy (BUSY_STAT bit is set) while previously instead of
  failing the function continued with checking for the correct device status
  (which would give the device additional 10 usec to clear BUSY_STAT bit).

* Remove stale comment for ide_config_drive_speed().

* Remove duplicate comment for ide_wait_stat() from <linux/ide.h>.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Fix pmac_ide_dma_check() to use pmac_ide_tune_chipset() and remove no longer
  necessary pmac_ide_{m,u}dma_enable().

* While at it remove some dead code from pmac_ide_dma_check() (leftovers from
  conversion to use ide_max_dma_mode()).

There should be no functionality changes caused by this patch.

v2:
* Fix compile by replacing "id" with "drive->id" in pmac_ide_dma_check()
  (Noticed by Ben).

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

pmac_ide_do_setfeature() contains matching nIEN setting/clearing so this
Device Control register messing in pmac_ide_dma_check() is totally unnecessary.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move adjusting of cycle time for devices providing explicit DMA cycle time
  from pmac_ide_mdma_enable() to set_timings_mdma().

* Remove no longer needed drive_cycle_time argument.

* BUG() if unsupported speed argument value is passed (shouldn't happen).

* Matching access/recovery timings always exist so remove redundant check.

* Make set_timings_mdma() void.

* Update pmac_ide_tune_chipset()'s comment.
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Don't check check for pmif == NULL (it should never be NULL if we got here).

* Make a local copy of the timings and set the pmif->timings[] only after
  setting the transfer mode on the device (otherwise SELECT_DRIVE() call in
  pmac_ide_do_setfeature() will program new timings before the transfer mode
  is set on the device - this was pointed out by Sergei).  This change makes
  pmac_ide_tune_chipset() behavior match this of pmac_ide_{m,u}dma_enable().
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

kauai_lookup_timing() should always return non-zero return value:

* BUG() in kauai_lookup_timing() if the timing info cannot be found.

* Remove code checking for zero return value from all callers.
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

This patch removes the unused EXPORT_SYMBOL_GPL(ide_acpi_set_state)
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

We need to set hwif->chipset or IDE PCI host drivers may try to claim
our ide_hwifs[] slot.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Fix DMI const-ification fallout that appeared when merging subsystem
trees.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

According to latest memory ordering specification documents from Intel
and AMD, both manufacturers are committed to in-order loads from
cacheable memory for the x86 architecture.  Hence, smp_rmb() may be a
simple barrier.

Also according to those documents, and according to existing practice in
Linux (eg.  spin_unlock doesn't enforce ordering), stores to cacheable
memory are visible in program order too.  Special string stores are safe
-- their constituent stores may be out of order, but they must complete
in order WRT surrounding stores.  Nontemporal stores to WB memory can go
out of order, and so they should be fenced explicitly to make them
appear in-order WRT other stores.  Hence, smp_wmb() may be a simple
barrier.

    http://developer.intel.com/products/processor/manuals/318147.pdf
    http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/24593.pdf

In userspace microbenchmarks on a core2 system, fence instructions range
anywhere from around 15 cycles to 50, which may not be totally
insignificant in performance critical paths (code size will go down
too).

However the primary motivation for this is to have the canonical barrier
implementation for x86 architecture.

smp_rmb on buggy pentium pros remains a locked op, which is apparently
required.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

wmb() on x86 must always include a barrier, because stores can go out of
order in many cases when dealing with devices (eg. WC memory).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

movnt* instructions are not strongly ordered with respect to other stores,
so if we are to assume stores are strongly ordered in the rest of the 64
bit code, we must fence these off (see similar examples in 32 bit code).

[ The AMD memory ordering document seems to say that nontemporal stores can
  also pass earlier regular stores, so maybe we need sfences _before_
  movnt* everywhere too? ]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

IOW, it needs to depend on both CONFIG_BLOCK and CONFIG_COMPAT.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev: (119 commits)
  [libata] struct pci_dev related cleanups
  libata: use ata_exec_internal() for PMP register access
  libata: implement ATA_PFLAG_RESETTING
  libata: add @timeout to ata_exec_internal[_sg]()
  ahci: fix notification handling
  ahci: clean up PORT_IRQ_BAD_PMP enabling
  ahci: kill leftover from enabling NCQ over PMP
  libata: wrap schedule_timeout_uninterruptible() in loop
  libata: skip suppress reporting if ATA_EHI_QUIET
  libata: clear ehi description after initial host report
  pata_jmicron: match vendor and class code only
  libata: add ST9160821AS / 3.ALD to NCQ blacklist
  pata_acpi: ACPI driver support
  libata-core: Expose gtm methods for driver use
  libata: add HDT722516DLA380 to NCQ blacklist
  libata: blacklist NCQ on Seagate Barracuda ST380817AS
  [libata] Turn on ACPI by default
  libata_scsi: Fix ATAPI transfer lengths
  libata: correct handling of SRST reset sequences
  libata: Integrate ACPI-based PATA/SATA hotplug - version 5
  ...

Since there is no x86-64 architecture anymore it cannot be maintained.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: (37 commits)
  PCI: merge almost all of pci_32.h and pci_64.h together
  PCI: X86: Introduce and enable PCI domain support
  PCI: Add 'nodomains' boot option, and pci_domains_supported global
  PCI: modify PCI bridge control ISA flag for clarity
  PCI: use _CRS for PCI resource allocation
  PCI: avoid P2P prefetch window for expansion ROMs
  PCI: skip ISA ioresource alignment on some systems
  PCI: remove transparent bridge sizing
  pci: write file size to inode on proc bus file write
  pci: use size stored in proc_dir_entry for proc bus files
  pci: implement "pci=noaer"
  PCI: fix IDE legacy mode resources
  MSI: Use correct data offset for 32-bit MSI in read_msi_msg()
  PCI: Fix incorrect argument order to list_add_tail() in PCI dynamic ID code
  PCI: i386: Compaq EVO N800c needs PCI bus renumbering
  PCI: Remove no longer correct documentation regarding MSI vector assignment
  PCI: re-enable onboard sound on "MSI K8T Neo2-FIR"
  PCI: quirk_vt82c586_acpi: Omit reading PCI revision ID
  PCI: quirk amd_8131_mmrbc: Omit reading pci revision ID
  cpqphp: Use PCI_CLASS_REVISION instead of PCI_REVISION_ID for read
  ...

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (75 commits)
  PM: merge device power-management source files
  sysfs: add copyrights
  kobject: update the copyrights
  kset: add some kerneldoc to help describe what these strange things are
  Driver core: rename ktype_edd and ktype_efivar
  Driver core: rename ktype_driver
  Driver core: rename ktype_device
  Driver core: rename ktype_class
  driver core: remove subsystem_init()
  sysfs: move sysfs file poll implementation to sysfs_open_dirent
  sysfs: implement sysfs_open_dirent
  sysfs: move sysfs_dirent->s_children into sysfs_dirent->s_dir
  sysfs: make sysfs_root a regular directory dirent
  sysfs: open code sysfs_attach_dentry()
  sysfs: make s_elem an anonymous union
  sysfs: make bin attr open get active reference of parent too
  sysfs: kill unnecessary NULL pointer check in sysfs_release()
  sysfs: kill unnecessary sysfs_get() in open paths
  sysfs: reposition sysfs_dirent->s_mode.
  sysfs: kill sysfs_update_file()
  ...

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6: (142 commits)
  USB: fix race in autosuspend reschedule
  atmel_usba_udc: Keep track of the device status
  USB: Nikon D40X unusual_devs entry
  USB: serial core should respect driver requirements
  USB: documentation for USB power management
  USB: skip autosuspended devices during system resume
  USB: mutual exclusion for EHCI init and port resets
  USB: allow usbstorage to have LUNS greater than 2Tb
  USB: Adding support for SHARP WS011SH to ipaq.c
  USB: add atmel_usba_udc driver
  USB: ohci SSB bus glue
  USB: ehci build fixes on au1xxx, ppc-soc
  USB: add runtime frame_no quirk for big-endian OHCI
  USB: funsoft: Fix termios
  USB: visor: termios bits
  USB: unusual_devs entry for Nikon DSC D2Xs
  USB: re-remove <linux/usb_sl811.h>
  USB: move <linux/usb_gadget.h> to <linux/usb/gadget.h>
  USB: Export URB statistics for powertop
  USB: serial gadget: Disable endpoints on unload
  ...

* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Don't take semaphore in cpufreq_quick_get()
  [CPUFREQ] Support different families in fid/did to frequency conversion
  [CPUFREQ] cpufreq_stats: misc cpuinit section annotations
  [CPUFREQ] implement !CONFIG_CPU_FREQ stub for  cpufreq_unregister_notifier()
  [CPUFREQ] mark hotplug notifier callback as __cpuinit
  [CPUFREQ] Only check for transition latency on problematic governors (kconfig fix)
  [CPUFREQ] allow ondemand and conservative cpufreq governors to be used as default
  [CPUFREQ] move policy's governor initialisation out of low-level drivers into cpufreq core
  [CPUFREQ] Longhaul - Add support for PM133 northbridge
  [CPUFREQ] x86: use num_online_nodes to get physical cpus numbers for

* git://git.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-x86: (40 commits)
  x86: HPET add another ICH7 PCI id
  x86: HPET force enable ICH5 suspend/resume fix
  x86: HPET force enable for ICH5
  x86: HPET try to activate force detected hpet
  x86: HPET force enable o ICH7 and later
  x86: HPET restructure hpet code for hpet force enable
  clock events: allow replacement of broadcast timer
  i386/x8664: cleanup the shared hpet code
  i386: Remove the useless #ifdef in i8253.h
  ACPI: remove the now unused ifdef code
  jiffies: remove unused macros
  x86_64: cleanup apic.c after clock events switch
  x86_64: remove now unused code
  x86: unify timex.h variants
  x86: kill 8253pit.h
  x86: disable apic timer for AMD C1E enabled CPUs
  x86: Fix irq0 / local apic timer accounting
  x86_64: convert to clock events
  x86_64: Add (not yet used) clock event functions
  x86_64: prepare idle loop for dynamic ticks
  ...

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: (23 commits)
  ocfs2: Optionally return filldir errors
  ocfs2: Write support for directories with inline data
  ocfs2: Read support for directories with inline data
  ocfs2: Write support for inline data
  ocfs2: Read support for inline data
  ocfs2: Structure updates for inline data
  ocfs2: Cleanup dirent size check
  ocfs2: Rename cleanups
  ocfs2: Provide convenience function for ino lookup
  ocfs2: Implement ocfs2_empty_dir() as a caller of ocfs2_dir_foreach()
  ocfs2: Remove open coded readdir()
  ocfs2: Pass raw u64 to filldir
  ocfs2: Abstract out core dir listing functionality
  ocfs2: Move directory manipulation code into dir.c
  ocfs2: Small refactor of truncate zeroing code
  ocfs2: move nonsparse hole-filling into ocfs2_write_begin()
  ocfs2: Sync ocfs2_fs.h with ocfs2-tools
  [PATCH] fs/ocfs2/: removed unneeded initial value and function's return value
  ocfs2: Implement show_options()
  ocfs2: Clear slot map when umounting a local volume
  ...

* 'isdn-cleanups' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/misc-2.6:
  [ISDN] HiSax diva: split setup into three smaller functions
  [ISDN] HiSax sedlbauer: move ISAPNP and PCI code into functions of their own
  [ISDN] HiSax elsa: split huge setup function into four smaller functions
  [ISDN] HiSax avm_pci: split setup into three smaller functions
  [ISDN] Remove CONFIG_PCI ifdefs from 100% PCI source code

It was just duplicated code...
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

* fix bug in pci_read() and pci_write() which prevented PCI domain
  support from working (hardcoded domain 0).

* unconditionally enable CONFIG_PCI_DOMAINS

* implement pci_domain_nr() and pci_proc_domain(), as required of
  all arches when CONFIG_PCI_DOMAINS is enabled.

* store domain in struct pci_sysdata, as assigned by ACPI

* support "pci=nodomains"
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

* Introduce pci_domains_supported global, hardcoded to zero if
  !CONFIG_PCI_DOMAINS.

* Introduce 'nodomains' boot option, which clears pci_domains_supported
  on platforms that enable it by default (x86, x86-64, and others when
  they are converted to use this).
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Modify PCI Bridge Control ISA flag for clarity

This patch changes PCI_BRIDGE_CTL_NO_ISA to PCI_BRIDGE_CTL_ISA
and modifies it's clarifying comment and locations where used.
The change reduces the chance of future confusion since it makes
the set/unset meaning of the bit the same in both the bridge
control register and bridge_ctl field of the pci_bus struct.
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Acked-by: Linas Vepstas <linas@austin.ibm.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

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: Gary Hade <gary.hade@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>