No functional change; this converts loops that iterate from 0 to
PCI_BUS_NUM_RESOURCES through pci_bus resource[] table to use the
pci_bus_for_each_resource() iterator instead.

This doesn't change the way resources are stored; it merely removes
dependencies on the fact that they're in a table.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Introduce run-time PM callbacks for the PCI bus type.  Make the new
callbacks work in analogy with the existing system sleep PM
callbacks, so that the drivers already converted to struct dev_pm_ops
can use their suspend and resume routines for run-time PM without
modifications.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Although the majority of PCI devices can generate PMEs that in
principle may be used to wake up devices suspended at run time,
platform support is generally necessary to convert PMEs into wake-up
events that can be delivered to the kernel.  If ACPI is used for this
purpose, PME signals generated by a PCI device will trigger the ACPI
GPE associated with the device to generate an ACPI wake-up event that
we can set up a handler for, provided that everything is configured
correctly.

Unfortunately, the subset of PCI devices that have GPEs associated
with them is quite limited.  The devices without dedicated GPEs have
to rely on the GPEs associated with other devices (in the majority of
cases their upstream bridges and, possibly, the root bridge) to
generate ACPI wake-up events in response to PME signals from them.

Add ACPI platform support for PCI PME wake-up:
o Add a framework making is possible to use ACPI system notify
  handlers for run-time PM.
o Add new PCI platform callback ->run_wake() to struct
  pci_platform_pm_ops allowing us to enable/disable the platform to
  generate wake-up events for given device.  Implemet this callback
  for the ACPI platform.
o Define ACPI wake-up handlers for PCI devices and PCI root buses and
  make the PCI-ACPI binding code register wake-up notifiers for all
  PCI devices present in the ACPI tables.
o Add function pci_dev_run_wake() which can be used by PCI drivers to
  check if given device is capable of generating wake-up events at
  run time.

Developed in cooperation with Matthew Garrett <mjg@redhat.com>.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

PCIe native PME detection mechanism is based on interrupts generated
by root ports or event collectors every time a PCIe device sends a
PME message upstream.

Once a PME message has been sent by an endpoint device and received
by its root port (or event collector in the case of root complex
integrated endpoints), the Requester ID from the message header is
registered in the root port's Root Status register.  At the same
time, the PME Status bit of the Root Status register is set to
indicate that there's a PME to handle.  If PCIe PME interrupt is
enabled for the root port, it generates an interrupt once the PME
Status has been set.  After receiving the interrupt, the kernel can
identify the PCIe device that generated the PME using the Requester
ID from the root port's Root Status register. [For details, see PCI
Express Base Specification, Rev. 2.0.]

Implement a driver for the PCIe PME root port service working in
accordance with the above description.

Based on a patch from Shaohua Li <shaohua.li@intel.com>.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The "is_pcie" field in struct pci_dev is no longer needed because
struct pci_dev has PCIe capability offset in "pcie_cap" field and
(pcie_cap != 0) means the device is PCIe capable. This patch marks
"is_pcie" fields obsolete.

Current users of "is_pcie" field are:

- drivers/ssb/scan.c
- drivers/net/wireless/ath/ath9k/pci.c
- drivers/net/wireless/ath/ath5k/attach.c
- drivers/net/wireless/ath/ath5k/reset.c
- drivers/acpi/hest.c
- drivers/pci/pcie/pme/pcie_pme.c

Will post patches for each to use pci_is_pcie() as a follow-up.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

For use by pciehp.

pci_setup_bridge() will not check enabled for the slot bridge, otherwise
update res is not updated to bridge BAR.  That is, bridge is already
enabled for port service.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Reviewed-by: NAlex Chiang <achiang@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The ISDN4Linux HiSax driver family contains the last remaining users
of the deprecated pci_find_device() function. This patch creates a
private copy of that function in HiSax, and removes the now unused
global function together with its controlling configuration option,
CONFIG_PCI_LEGACY.
Signed-off-by: NTilman Schmidt <tilman@imap.cc>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Now that we return the new resource start position, there is no
need to update "struct resource" inside the align function.
Therefore, mark the struct resource as const.

Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

As suggested by Linus, align functions should return the start
of a resource, not void. An update of "res->start" is no longer
necessary.

Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Currently, drivers/pci/quirks.c is built unconditionally, but if
CONFIG_PCI_QUIRKS is unset, the only things actually built in this
file are definitions of global variables and empty functions (due to
the #ifdef CONFIG_PCI_QUIRKS embracing all of the code inside the
file).  This is not particularly nice and if someone overlooks
the #ifdef CONFIG_PCI_QUIRKS, build errors are introduced.

To clean that up, move the definitions of the global variables in
quirks.c that are always built to pci.c, move the definitions of
the empty functions (compiled when CONFIG_PCI_QUIRKS is unset) to
headers (additionally make these functions static inline) and modify
drivers/pci/Makefile so that quirks.c is only built if
CONFIG_PCI_QUIRKS is set.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Add the 8.0 GT/s speed.
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Take advantage of some gaps in the table to fit in support for AGP speeds.
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NJesse 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: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

These enums must not overlap anyway, since we only have a single
pci_bus_speed_strings array.  Use a single enum, and move it to
pci.h.  Add 'SPEED' to the pcie names to make it clear what they are.
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

We are missing these when building the pci_dev from scratch off
the Open Firmware device-tree
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>

It turns out that some PCI devices require extra delays when changing
power state from D3 to D0 (and the other way around).  Although this
is against the PCI specification, we can handle it quite easily by
allowing drivers to define arbitrary D3 delays for devices known to
require extra time for switching power states.

Introduce additional field d3_delay in struct pci_dev and use it to
store the value of the device's D0->D3 delay, in miliseconds.  Make
the PCI PM core code use the per-device d3_delay unless
pci_pm_d3_delay is greater (in which case the latter is used).
[This also allows the driver to specify d3_delay shorter than the
 10 ms required by the PCI standard if the device is known to be able
 to handle that.]

Make the sky2 driver set d3_delay to 150 for devices handled by it.

Fixes http://bugzilla.kernel.org/show_bug.cgi?id=14730 which is a
listed regression from 2.6.30.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

The cardbus code creates PCI devices without ever going through the
necessary fixup bits and pieces that normal PCI devices go through.

There's in fact a commented out call to pcibios_fixup_bus() in there,
it's commented because ... it doesn't work.

I could make pcibios_fixup_bus() do the right thing on powerpc easily
but I felt it cleaner instead to provide a specific hook pci_fixup_cardbus
for which a weak empty implementation is provided by the PCI core.

This fixes cardbus on powerbooks and probably all other PowerPC
platforms which was broken completely for ever on some platforms and
since 2.6.31 on others such as PowerBooks when we made the DMA ops
mandatory (since those are setup by the fixups).
Acked-by: NDominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Global variable declarations must match the definitions in section attributes
as the compiler is at liberty to vary the method it uses to access a variable,
depending on the section it is in.

When building the FRV arch, I now see:

  drivers/built-in.o: In function `pci_apply_final_quirks':
  drivers/pci/quirks.c:2606: relocation truncated to fit: R_FRV_GPREL12 against symbol `pci_dfl_cache_line_size' defined in .devinit.data section in drivers/built-in.o
  drivers/pci/quirks.c:2623: relocation truncated to fit: R_FRV_GPREL12 against symbol `pci_dfl_cache_line_size' defined in .devinit.data section in drivers/built-in.o
  drivers/pci/quirks.c:2630: relocation truncated to fit: R_FRV_GPREL12 against symbol `pci_dfl_cache_line_size' defined in .devinit.data section in drivers/built-in.o

because the declaration of pci_dfl_cache_line_size in linux/pci.h does not
match the definition in drivers/pci/pci.c.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit ae21ee65 "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: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Introduce pci_is_pcie() which returns true if the specified PCI device
is PCI Express capable, false otherwise.

The purpose of pci_is_pcie() is removing 'is_pcie' flag in the struct
pci_dev, which is not needed because we can check it using 'pcie_cap'
field. To remove 'is_pcie', we need to update user of 'is_pcie' to use
pci_is_pcie() instead first.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Introduce pci_pcie_cap() API that returns saved PCIe capability offset
(currently it is saved in 'pcie_cap' field in the struct PCI dev).
Using pci_pcie_cap() instead of pci_find_capability() avoids
unnecessary search in PCI configuration space.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse 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: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Added the pci_get_domain_and_slot_function which is analogous to
pci_get_bus_and_slot. It returns a pci_dev given a domain (segment) number,
bus number, and devnr. Like pci_get_bus_and_slot,
pci_get_domain_bus_and_slot holds a reference to the returned pci_dev.

Converted pci_get_bus_and_slot to a wrapper that calls
pci_get_domain_bus_and_slot with the domain hard-coded to 0.

This routine was patterned off code suggested by Bjorn Helgaas.
Acked-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NAndrew Patterson <andrew.patterson@hp.com>
Signed-off-by: NJesse 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: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: NHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: NMatt Domsch <Matt_Domsch@dell.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

For non hotplug PCI devices, the system firmware usually configures
CLS correctly.  For pccard devices system firmware can't do it and
Linux PCI layer doesn't do it either.  Unfortunately this leads to
poor performance for certain devices (sata_sil).  Unless MWI, which
requires separate configuration, is to be used, CLS doesn't affect
correctness, so the configuration should be harmless.

This patch makes pci_set_cacheline_size() always built and export it
and make pccard call it during attach.

Please note that some other PCI hotplug drivers (shpchp and pciehp)
also configure CLS on hotplug.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Daniel Ritz <daniel.ritz@gmx.ch>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Greg KH <greg@kroah.com>
Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Cc: Axel Birndt <towerlexa@gmx.de>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Till now, CLS has been determined either by arch code or as
L1_CACHE_BYTES.  Only x86 and ia64 set CLS explicitly and x86 doesn't
always get it right.  On most configurations, the chance is that
firmware configures the correct value during boot.

This patch makes pci_init() determine CLS by looking at what firmware
has configured.  It scans all devices and if all non-zero values
agree, the value is used.  If none is configured or there is a
disagreement, pci_dfl_cache_line_size is used.  arch can set the dfl
value (via PCI_CACHE_LINE_BYTES or pci_dfl_cache_line_size) or
override the actual one.

ia64, x86 and sparc64 updated to set the default cls instead of the
actual one.

While at it, declare pci_cache_line_size and pci_dfl_cache_line_size
in pci.h and drop private declarations from arch code.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid Miller <davem@davemloft.net>
Acked-by: NGreg KH <gregkh@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Introduce a new PCI device flag, wakeup_prepared, to prevent PCI
wake-up preparation code from being executed twice in a row for the
same device and for the same purpose.
Reviewed-by: NMatthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NJesse 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: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Separate out pci_add_dynid() from store_new_id() and export it so that
in-kernel code can add PCI IDs dynamically.  As the function will be
available regardless of HOTPLUG, put it and pull pci_free_dynids()
outside of CONFIG_HOTPLUG.

This will be used by pci-stub to initialize initial IDs via module
param.

While at it, remove bogus get_driver() failure check.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: NGrant Grundler <grundler@parisc-linux.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This is the first of three patches that implement a bit field that PCI
Express device drivers can use to indicate they need a fundamental reset
during error recovery.

By default, the EEH framework on powerpc does what's known as a "hot
reset" during recovery of a PCI Express device.  We've found a case
where the device needs a "fundamental reset" to recover properly.  The
current PCI error recovery and EEH frameworks do not support this
distinction.

The attached patch (courtesy of Richard Lary) adds a bit field to
pci_dev that indicates whether the device requires a fundamental reset
during recovery.

These patches supersede the previously submitted patch that implemented
a fundamental reset bit field.
Signed-off-by: NMike Mason <mmlnx@us.ibm.com>
Signed-off-by: NRichard Lary <rlary@us.ibm.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Background:
Graphic devices are accessed through ranges in I/O or memory space. While most
modern devices allow relocation of such ranges, some "Legacy" VGA devices
implemented on PCI will typically have the same "hard-decoded" addresses as
they did on ISA. For more details see "PCI Bus Binding to IEEE Std 1275-1994
Standard for Boot (Initialization Configuration) Firmware Revision 2.1"
Section 7, Legacy Devices.

The Resource Access Control (RAC) module inside the X server currently does
the task of arbitration when more than one legacy device co-exists on the same
machine. But the problem happens when these devices are trying to be accessed
by different userspace clients (e.g. two server in parallel). Their address
assignments conflict. Therefore an arbitration scheme _outside_ of the X
server is needed to control the sharing of these resources. This document
introduces the operation of the VGA arbiter implemented for Linux kernel.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NTiago Vignatti <tiago.vignatti@nokia.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Some devices allow an individual function to be reset without affecting
other functions in the same device: that's what pci_reset_function does.
For devices that have this support, expose reset attribite in sysfs.

This is useful e.g. for virtualization, where a qemu userspace
process wants to reset the device when the guest is reset,
to emulate machine reboot as closely as possible.
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Since this function should never modify it (saves warnings when called with
const args too).
Signed-off-by: NAlexey Zaytsev <zaytsev@altell.ru>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Other functions use type bool, so use that for pci_enable_wake as well.
Signed-off-by: NFrans Pop <elendil@planet.nl>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This patch enhances the FLR functions:
  1) remove disable_irq() so the shared IRQ won't be disabled.
  2) replace the 1s wait with 100, 200 and 400ms wait intervals
     for the Pending Transaction.
  3) replace mdelay() with msleep().
  4) add might_sleep().
  5) lock the device to prevent PM suspend from accessing the CSRs
     during the reset.
  6) coding style fixes.
Reviewed-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NYu Zhao <yu.zhao@intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Based on PCI Express AER specs, a root port might receive multiple
TLP errors while it could only save a correctable error source id
and an uncorrectable error source id at the same time. In addition,
some root port hardware might be unable to provide a correct source
id, i.e., the source id, or the bus id part of the source id provided
by root port might be equal to 0.

The patchset implements the support in kernel by searching the device
tree under the root port.

Patch 1 changes parameter cb of function pci_walk_bus to return a value.
When cb return non-zero, pci_walk_bus stops more searching on the
device tree.
Reviewed-by: NAndrew Patterson <andrew.patterson@hp.com>
Signed-off-by: NZhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Create symbolic link to hotplug driver module in the PCI slot
directory (/sys/bus/pci/slots/<SLOT#>). In the past, we need to load
hotplug drivers one by one to identify the hotplug driver that handles
the slot, and it was very inconvenient especially for trouble shooting.
With this change, we can easily identify the hotplug driver.
Signed-off-by: NTaku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: NAlex Chiang <achiang@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

pci_bus_set_ops changes pci_ops associated with a pci_bus. This can be
used by debug tools such as PCIE AER error injection to fake some PCI
configuration registers.
Acked-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

This patch (as1235) adds an array of PCI power-state names, together
with a simple inline accessor routine.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Adds support for PCI Express transaction layer end-to-end CRC checking
(ECRC).  This patch will enable/disable ECRC checking by setting/clearing
the ECRC Check Enable and/or ECRC Generation Enable bits for devices that
support ECRC.

The ECRC setting is controlled by the "pci=ecrc=<policy>" command-line
option. If this option is not set or is set to 'bios", the enable and
generation bits are left in whatever state that firmware/BIOS set them to.
The "off" setting turns them off, and the "on" option turns them on (if the
device supports it).

Turning ECRC on or off can be a data integrity versus performance
tradeoff.  In theory, turning it on will catch more data errors, turning
it off means possibly better performance since CRC does not need to be
calculated by the PCIe hardware and packet sizes are reduced.
Signed-off-by: NAndrew Patterson <andrew.patterson@hp.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>