Commit Graph

192 Commits

Author SHA1 Message Date
Benjamin Herrenschmidt
deb2d2ecd4 PCI/GPU: implement VGA arbitration on Linux
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: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Tiago Vignatti <tiago.vignatti@nokia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 13:29:36 -07:00
Michael S. Tsirkin
711d57796f PCI: expose function reset capability in sysfs
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: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-09-09 13:29:24 -07:00
Alek Du
c82f63e411 PCI: check saved state before restore
Without the check, the config space may be filled with zeros. Though
the driver should try to avoid call restoring before saving, but the
pci layer also should check this.

Also removes the existing check in pci_restore_standard_config, since
it's superfluous with the new check in restore_state.

Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-08-20 09:08:45 -07:00
Matthew Wilcox
46b952a3c3 PCI: Fix IRQ swizzling for ARI-enabled devices
For many purposes, including interrupt-swizzling, devices with ARI
enabled behave as if they have one device (number 0) and 256 functions.
This probably hasn't bitten us in practice because all ARI devices I've
seen are also IOV devices, and IOV devices are required to use MSI.
This isn't guaranteed, and there are legitimate reasons to use ARI
without IOV, and hence potentially use pin-based interrupts.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-07-01 14:24:30 -07:00
Yu Zhao
654b75e044 PCI: check if bus has a proper bridge device before triggering SBR
For devices attached to the root bus, we can't trigger Secondary Bus
Reset because there is no bridge device associated with the bus. So
need to check bus->self again NULL first before using it.

Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-29 12:13:13 -07:00
Linus Torvalds
59ef7a83f1 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (74 commits)
  PCI: make msi_free_irqs() to use msix_mask_irq() instead of open coded write
  PCI: Fix the NIU MSI-X problem in a better way
  PCI ASPM: remove get_root_port_link
  PCI ASPM: cleanup pcie_aspm_sanity_check
  PCI ASPM: remove has_switch field
  PCI ASPM: cleanup calc_Lx_latency
  PCI ASPM: cleanup pcie_aspm_get_cap_device
  PCI ASPM: cleanup clkpm checks
  PCI ASPM: cleanup __pcie_aspm_check_state_one
  PCI ASPM: cleanup initialization
  PCI ASPM: cleanup change input argument of aspm functions
  PCI ASPM: cleanup misc in struct pcie_link_state
  PCI ASPM: cleanup clkpm state in struct pcie_link_state
  PCI ASPM: cleanup latency field in struct pcie_link_state
  PCI ASPM: cleanup aspm state field in struct pcie_link_state
  PCI ASPM: fix typo in struct pcie_link_state
  PCI: drivers/pci/slot.c should depend on CONFIG_SYSFS
  PCI: remove redundant __msi_set_enable()
  PCI PM: consistently use type bool for wake enable variable
  x86/ACPI: Correct maximum allowed _CRS returned resources and warn if exceeded
  ...
2009-06-22 11:59:51 -07:00
Frans Pop
7d9a73f6dc PCI PM: consistently use type bool for wake enable variable
Other functions use type bool, so use that for pci_enable_wake as well.

Signed-off-by: Frans Pop <elendil@planet.nl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 15:19:02 -07:00
Rafael J. Wysocki
d2abdf6288 PCI PM: Fix handling of devices without PM support by pci_target_state()
If a PCI device is not power-manageable either by the platform, or
with the help of the native PCI PM interface, pci_target_state() will
return either PCI_D3hot, or PCI_POWER_ERROR for it, depending on
whether or not the device is configured to wake up the system.  Alas,
none of these return values is correct, because each of them causes
pci_prepare_to_sleep() to return error code, although it should
complete successfully in such a case.

Fix this problem by making pci_target_state() always return PCI_D0
for devices that cannot be power managed.

Cc: stable@kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:17 -07:00
Yu Zhao
c12ff1df5f PCI: support Secondary Bus Reset
PCI-to-PCI Bridge 1.2 specifies that the Secondary Bus Reset bit can
force the assertion of RST# on the secondary interface, which can be
used to reset all devices including subordinates under this bus. This
can be used to reset a function if this function is the only device
under this bus.

Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:16 -07:00
Yu Zhao
f85876ba82 PCI: support PM D0hot->D3 transition reset
PCI PM 1.2 specifies that the device will perform an internal reset upon
transitioning from D3hot to D0 when the NO_SOFT_RESET bit is clear. This
method can be used to reset a function if neither PCIe FLR nor PCI AF FLR
are supported.

Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:16 -07:00
Yu Zhao
8c1c699fec PCI: cleanup Function Level Reset
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: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:30:15 -07:00
Kenji Kaneshige
1eb3948716 PCI: use pci_is_root_bus() in pci_common_swizzle()
Use pci_is_root_bus() in pci_common_swizzle() for checking if the pci
bus is root, for code consistency.

Reviewed-by: Alex Chiang <achiang@hp.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:29:32 -07:00
Kenji Kaneshige
8784fd4d49 PCI: use pci_is_root_bus() in pci_get_interrupt_pin()
Use pci_is_root_bus() in pci_get_interrupt_pin() for checking if the
pci bus is root, for code consistency.

Reviewed-by: Alex Chiang <achiang@hp.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-16 14:29:31 -07:00
Alan Stern
00240c3839 PCI: add power-state name strings
This patch (as1235) adds an array of PCI power-state names, together
with a simple inline accessor routine.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:44 -07:00
Andrew Patterson
43c1640884 PCI: Add support for turning PCIe ECRC on or off
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: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-11 12:04:21 -07:00
Rafael J. Wysocki
f62795f1e8 PCI PM: Follow PCI_PM_CTRL_NO_SOFT_RESET during transitions from D3
According to the PCI PM specification (PCI Bus Power Management
Interface Specification, Rev. 1.2, Section 5.4.1) we are supposed to
reinitialize devices that have PCI_PM_CTRL_NO_SOFT_RESET clear during
all transitions from PCI_D3hot to PCI_D0, but we only do it if the
device's current_state field is equal to PCI_UNKNOWN.

This may lead to problems if a device with PCI_PM_CTRL_NO_SOFT_RESET
unset is put into PCI_D3hot at run time by its driver and
pci_set_power_state() is used to put it back into PCI_D0, because in
that case the device will remain uninitialized after
pci_set_power_state() has returned.  Prevent that from happening by
modifying pci_raw_set_power_state() to reinitialize devices with
PCI_PM_CTRL_NO_SOFT_RESET unset during all transitions from D3 to D0.

Cc: stable@kernel.org
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-06-11 12:04:20 -07:00
Rafael J. Wysocki
b3bad72e49 PCI PM: Fix initialization and kexec breakage for some devices
Recent PCI PM changes introduced a bug that causes some devices to be
mishandled after kexec and during early initialization.  The failure
scenario in the kexec case is the following:

* Assume a PCI device is not power-manageable by the platform and has
  PCI_PM_CTRL_NO_SOFT_RESET set in PMCSR.
* The device is put into D3 before kexec (using the native PCI PM).
* After kexec, pci_setup_device() sets the device's power state to
  PCI_UNKNOWN.
* pci_set_power_state(dev, PCI_D0) is called by the device's driver.
* __pci_start_power_transition(dev, PCI_D0) is called and since the
  device is not power-manageable by the platform, it causes
  pci_update_current_state(dev, PCI_D0) to be called.  As a result
  the device's current_state field is updated to PCI_D3, in
  accordance with the contents of its PCI PM registers.
* pci_raw_set_power_state() is called and it changes the device power
  state to D0.  *However*, it should also call pci_restore_bars() to
  reinitialize the device, but it doesn't, because the device's
  current_state field has been modified earlier.

To prevent this from happening, modify pci_platform_power_transition()
so that it doesn't use pci_update_current_state() to update the
current_state field for devices that aren't power-manageable by the
platform.  Instead, this field should be updated directly for devices
that don't support the native PCI PM.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-05-19 15:26:07 -07:00
Yu Zhao
1b6b8ce2ac PCI: only save/restore existent registers in the PCIe capability
PCIe 1.1 base neither requires the endpoint to implement the entire
PCIe capability structure nor specifies default values of registers
that are not implemented by the device. So we only save and restore
registers that must be implemented by different device types if the
device PCIe capability version is 1.

PCIe 1.1 Capability Structure Expansion ECN and PCIe 2.0 requires
all registers in the PCIe capability to be either implemented or
hardwired to 0. Their PCIe capability version is 2.

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-04-22 15:59:41 -07:00
Yuji Shimada
296ccb086d PCI: Setup disabled bridges even if buses are added
This patch sets up disabled bridges even if buses have already been
added.

pci_assign_unassigned_resources is called after buses are added.
pci_assign_unassigned_resources calls pci_bus_assign_resources.
pci_bus_assign_resources calls pci_setup_bridge to configure BARs of
bridges.

Currently pci_setup_bridge returns immediately if the bus have already
been added. So pci_assign_unassigned_resources can't configure BARs of
bridges that were added in a disabled state; this patch fixes the issue.

On logical hot-add, we need to prevent the kernel from re-initializing
bridges that have already been initialized. To achieve this,
pci_setup_bridge returns immediately if the bridge have already been
enabled.

We don't need to check whether the specified bus is a root bus or not.
pci_setup_bridge is not called on a root bus, because a root bus does
not have a bridge.

The patch adds a new helper function, pci_is_enabled. I made the
function name similar to pci_is_managed. The codes which use
enable_cnt directly are changed to use pci_is_enabled.

Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Yuji Shimada <shimada-yxb@necst.nec.co.jp>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-04-06 11:25:06 -07:00
Linus Torvalds
811158b147 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  trivial: Update my email address
  trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
  trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
  trivial: Fix misspelling of "Celsius".
  trivial: remove unused variable 'path' in alloc_file()
  trivial: fix a pdlfush -> pdflush typo in comment
  trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
  trivial: wusb: Storage class should be before const qualifier
  trivial: drivers/char/bsr.c: Storage class should be before const qualifier
  trivial: h8300: Storage class should be before const qualifier
  trivial: fix where cgroup documentation is not correctly referred to
  trivial: Give the right path in Documentation example
  trivial: MTD: remove EOL from MODULE_DESCRIPTION
  trivial: Fix typo in bio_split()'s documentation
  trivial: PWM: fix of #endif comment
  trivial: fix typos/grammar errors in Kconfig texts
  trivial: Fix misspelling of firmware
  trivial: cgroups: documentation typo and spelling corrections
  trivial: Update contact info for Jochen Hein
  trivial: fix typo "resgister" -> "register"
  ...
2009-04-03 15:24:35 -07:00
Linus Torvalds
e76e5b2c66 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (88 commits)
  PCI: fix HT MSI mapping fix
  PCI: don't enable too much HT MSI mapping
  x86/PCI: make pci=lastbus=255 work when acpi is on
  PCI: save and restore PCIe 2.0 registers
  PCI: update fakephp for bus_id removal
  PCI: fix kernel oops on bridge removal
  PCI: fix conflict between SR-IOV and config space sizing
  powerpc/PCI: include pci.h in powerpc MSI implementation
  PCI Hotplug: schedule fakephp for feature removal
  PCI Hotplug: rename legacy_fakephp to fakephp
  PCI Hotplug: restore fakephp interface with complete reimplementation
  PCI: Introduce /sys/bus/pci/devices/.../rescan
  PCI: Introduce /sys/bus/pci/devices/.../remove
  PCI: Introduce /sys/bus/pci/rescan
  PCI: Introduce pci_rescan_bus()
  PCI: do not enable bridges more than once
  PCI: do not initialize bridges more than once
  PCI: always scan child buses
  PCI: pci_scan_slot() returns newly found devices
  PCI: don't scan existing devices
  ...

Fix trivial append-only conflict in Documentation/feature-removal-schedule.txt
2009-04-01 09:47:12 -07:00
Rafael J. Wysocki
8efb8c76fc PCI PM: Make pci_prepare_to_sleep() disable wake-up if needed
If the device is not supposed to wake up the system, ie. when
device_may_wakeup(&dev->dev) returns 'false', pci_prepare_to_sleep()
should pass 'false' to pci_enable_wake() so that it calls the
platform to disable the wake-up capability of the device.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-30 21:46:56 +02:00
Rafael J. Wysocki
0e5dd46b76 PCI PM: Introduce __pci_[start|complete]_power_transition() (rev. 2)
The radeonfb driver needs to program the device's PMCSR directly due
to some quirky hardware it has to handle (see
http://bugzilla.kernel.org/show_bug.cgi?id=12846 for details) and
after doing that it needs to call the platform (usually ACPI) to
finish the power transition of the device.  Currently it uses
pci_set_power_state() for this purpose, however making a specific
assumption about the internal behavior of this function, which has
changed recently so that this assumption is no longer satisfied.
For this reason, introduce __pci_complete_power_transition() that may
be called by the radeonfb driver to complete the power transition of
the device.  For symmetry, introduce __pci_start_power_transition().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-30 21:46:56 +02:00
Rafael J. Wysocki
4a865905f6 PCI PM: Make pci_set_power_state() handle devices with no PM support
There is a problem with PCI devices without any PM support (either
native or through the platform) that pci_set_power_state() always
returns error code for them, even if they are being put into D0.
However, such devices are always in D0, so pci_set_power_state()
should return success when attempting to put such a device into D0.
It also should update the current_state field for these devices as
appropriate.  This modification is necessary so that the standard
configuration registers of these devices are successfully restored by
pci_restore_standard_config() during the "early" phase of resume.

In addition, pci_set_power_state() should check the value of
current_state before calling the platform to change the power state
of the device to avoid doing that unnecessarily.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-30 21:46:56 +02:00
Rafael J. Wysocki
0128a89cf7 PCI PM: Move pci_restore_standard_config to pci-driver.c
Move pci_restore_standard_config() from pci.c to pci-driver.c and
make it static.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-30 21:46:55 +02:00
Rafael J. Wysocki
f00a20ef46 PCI PM: Use pci_set_power_state during early resume
Once we have allowed timer interrupts to be enabled during the early
phase of resuming devices, we are now able to use the generic
pci_set_power_state() to put PCI devices into D0 at that time.  Then,
the platform-specific PM code will have a chance to handle devices
that don't implement the native PCI PM or that require some
additional, platform-specific operations to be carried out to power
them up.  Also, by doing this we can simplify the code quite a bit.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-30 21:46:55 +02:00
Nick Andrew
877d03105d trivial: Fix misspelling of firmware
Fix misspelling of firmware.

Signed-off-by: Nick Andrew <nick@nick-andrew.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-03-30 15:21:59 +02:00
Yu Zhao
898585172f PCI: save and restore PCIe 2.0 registers
PCIe 2.0 defines several new registers (Device Control 2, Link Control 2,
and Slot Control 2). Save and retore them in pci_save_pcie_state() and
pci_restore_pcie_state().

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-26 16:02:30 -07:00
Yu Zhao
8c5cdb6adc PCI: restore saved SR-IOV state
Restore the volatile registers in the SR-IOV capability after the
D3->D0 transition.

Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 10:48:24 -07:00
Yu Zhao
d1b054da8f PCI: initialize and release SR-IOV capability
If a device has the SR-IOV capability, initialize it (set the ARI
Capable Hierarchy in the lowest numbered PF if necessary; calculate
the System Page Size for the VF MMIO, probe the VF Offset, Stride
and BARs). A lock for the VF bus allocation is also initialized if
a PF is the lowest numbered PF.

Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 10:48:22 -07:00
Yuji Shimada
32a9a682be PCI: allow assignment of memory resources with a specified alignment
This patch allows memory resources to be assigned with a specified
alignment at boot-time or run-time. The patch is useful when we use PCI
pass-through, because page-aligned memory resources are required to
securely share PCI resources with guest drivers.

If you want to assign the resource at boot time, please set
"pci=resource_alignment=" boot parameter.

This is format of "pci=resource_alignment=" boot parameter:

        [<order of align>@][<domain>:]<bus>:<slot>.<func>[; ...]
                Specifies alignment and device to reassign
                aligned memory resources.
                If <order of align> is not specified, PAGE_SIZE is
                used as alignment.
                PCI-PCI bridge can be specified, if resource
                windows need to be expanded.

This is example:

        pci=resource_alignment=20@07:00.0;18@0f:00.0;00:1d.7

If you want to assign the resource at run-time, please set
"/sys/bus/pci/resource_alignment" file, and hot-remove the device and
hot-add the device.  For this purpose, fakephp or PCI hotplug interfaces
can be used.

The format of "/sys/bus/pci/resource_alignment" file is the same with
boot parameter. You can use "," instead of ";".

For example:

        # cd /sys/bus/pci
        # echo -n 20@12:00.0 > resource_alignment
        # echo 1 > devices/0000:12:00.0/remove
        # echo 1 > rescan

Reviewed-by: Alex Chiang <achiang@hp.com>
Reviewed-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Yuji Shimada <shimada-yxb@necst.nec.co.jp>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 10:48:15 -07:00
Kenji Kaneshige
c74d724462 PCI: fix wrong assumption in pci_common_swizzle
Current pci_common_swizzle() seems to have a assumption that
pci_bus->self is NULL on the pci root bus. But it might not be true on
some platforms. Because of this wrong assumption, pci_common_swizzle()
might cause endless loop. We must check pci_bus->parent instead.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 10:48:05 -07:00
Kenji Kaneshige
c2a3072e01 PCI: fix wrong assumption in pci_get_interrupt_pin
Current pci_get_interrupt_pin() seems to have an assumption that
pci_bus->self is NULL on the root pci bus. But it might not be true on
some platforms. Because of this wrong assumption, current
pci_get_interrupt_pin() might cause endless loop. We must check
pci_bus->parent instead.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-20 10:48:04 -07:00
Sheng Yang
5fe5db05f6 PCI: Speed up device reset function
For all devices need to do function level reset, currently we need wait for
at least 200ms, which can be too long if we have lots of devices...

The patch checked pending bit before msleep() to skip some unnecessary
sleeping interval.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19 19:29:31 -07:00
Harvey Harrison
e496b617b4 PCI: __FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19 19:29:20 -07:00
Randy Dunlap
f5ddcac435 PCI: fix missing kernel-doc and typos
Fix pci kernel-doc parameter missing notation, correct
function name, and fix typo:

Warning(linux-2.6.28-git10//drivers/pci/pci.c:1511): No description found for parameter 'exclusive'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-02-13 12:03:08 -08:00
Rafael J. Wysocki
49c968111a PCI PM: Read power state from device after trying to change it on resume
pci_restore_standard_config() unconditionally changes current_state
to PCI_D0 after attempting to change the device's power state, but
it should rather read the actual current power state from the
device.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-02-04 17:22:28 -08:00
Rafael J. Wysocki
144a76bc88 PCI PM: Check if the state has been saved before trying to restore it
Check if the standard configuration registers of a PCI device have
been saved during suspend before trying to restore them during
resume.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-By: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-02-04 17:20:39 -08:00
Rafael J. Wysocki
476e7faefc PCI PM: Do not wait for buses in B2 or B3 during resume
pci_restore_standard_config() adds extra delay for PCI buses in
low power states (B2 or B3), but this is only correct for buses in
B2, because the buses in B3 are reset when they are put back into
B0.  Thus we should wait for such buses to settle after the reset,
but it's not a good idea to wait that long (1.1 s) with interrupts
off.

On the other hand, we have never waited for buses in B2 and B3
during resume and it seems reasonable to go back to this well
tested behaviour.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-27 09:47:10 -08:00
Rafael J. Wysocki
48f67f54a5 PCI PM: Power up devices before restoring their state
Devices that have MSI-X enabled before suspend to RAM or hibernation
and that are in a low power state during resume will not be handled
correctly by pci_restore_standard_config().  Namely, it first calls
pci_restore_state() which calls pci_restore_msi_state(), which in turn
executes __pci_restore_msix_state() that accesses the device's memory
space to restore the contents of the MSI-X table.  However, if the
device is in a low power state at this point, it's memory space is
not accessible.

The easiest way to fix this potential problem is to make
pci_restore_standard_config() call pci_restore_state() after
it has put the device into the full power state, D0.  Fortunately,
all of this is done with interrupts off, so the change of ordering
should not cause any trouble.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-27 09:47:02 -08:00
Rafael J. Wysocki
aa8c6c9374 PCI PM: Restore standard config registers of all devices early
There is a problem in our handling of suspend-resume of PCI devices that
many of them have their standard config registers restored with
interrupts enabled and they are put into the full power state with
interrupts enabled as well.  This may lead to the following scenario:
  * an interrupt vector is shared between two or more devices
  * one device is resumed earlier and generates an interrupt
  * the interrupt handler of another device tries to handle it and
    attempts to access the device the config space of which hasn't been
    restored yet and/or which still is in a low power state
  * the system crashes as a result

To prevent this from happening we should restore the standard
configuration registers of all devices with interrupts disabled and we
should put them into the D0 power state right after that.
Unfortunately, this cannot be done using the existing
pci_set_power_state(), because it can sleep.  Also, to do it we have to
make sure that the config spaces of all devices were actually saved
during suspend.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-16 12:57:58 -08:00
Linus Torvalds
50246dd41c Revert "PCI PM: Register power state of devices during initialization"
This reverts commit 98e6e286d7, as Yinghai
Lu reports that it breaks kexec with at least the e1000 and e1000e
drivers.  The reason is that the shutdown sequence puts the hardware
into D3 sleep, and the commit causes us to claim that it then is in D0
(running) state just because we don't understand the PM capabilities.

Which then later makes "pci_set_power_state()" not do anything, and the
device never wakes up properly and just returns 0xff to everything.

Reported-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: From: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Jesse Barnes <jesse.barnes@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-16 08:14:51 -08:00
Rafael J. Wysocki
98e6e286d7 PCI PM: Register power state of devices during initialization
Use the observation that the power state of a PCI device can be
loaded into its pci_dev structure as soon as pci_pm_init() is run for
it and make that happen.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:18:04 -08:00
Rafael J. Wysocki
734104292f PCI PM: Avoid touching devices behind bridges in unknown state
It generally is better to avoid accessing devices behind bridges that
may not be in the D0 power state, because in that case the bridges'
secondary buses may not be accessible.  For this reason, during the
early phase of resume (ie. with interrupts disabled), before
restoring the standard config registers of a device, check the power
state of the bridge the device is behind and postpone the restoration
of the device's config space, as well as any other operations that
would involve accessing the device, if that state is not D0.

In such cases the restoration of the device's config space will be
retried during the "normal" phase of resume (ie. with interrupts
enabled), so that the bridge can be put into D0 before that happens.

Also, save standard configuration registers of PCI devices during the
"normal" phase of suspend (ie. with interrupts enabled), so that the
bridges the devices are behind can be put into low power states (we
don't put bridges into low power states at the moment, but we may
want to do it in the future and it seems reasonable to design for
that).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:16:05 -08:00
Rafael J. Wysocki
fa58d305d9 PCI PM: Add suspend counterpart of pci_reenable_device
PCI devices without drivers are not disabled during suspend and
hibernation, but they are enabled during resume, with the help of
pci_reenable_device(), so there is an unbalanced execution of
pcibios_enable_device() in the resume code path.

To correct this introduce function pci_disable_enabled_device()
that will disable the argument device, if it is enabled when the
function is being run, without updating the device's pci_dev
structure and use it in the suspend code path to balance the
pci_reenable_device() executed during resume.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:14:40 -08:00
Ben Hutchings
6a479079c0 PCI: Add pci_clear_master() as opposite of pci_set_master()
During an online device reset it may be useful to disable bus-mastering.
pci_disable_device() does that, and far more besides, so is not suitable
for an online reset.

Add pci_clear_master() which does just this.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:23 -08:00
Bjorn Helgaas
68feac87de PCI: add pci_common_swizzle() for INTx swizzling
This patch adds pci_common_swizzle(), which swizzles INTx values all the
way up to a root bridge.

This common implementation can replace several architecture-specific
ones.  This should someday be combined with pci_get_interrupt_pin(),
but I left it separate for now to make reviewing easier.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:12 -08:00
Rafael J. Wysocki
f06fc0b6f8 PCI PM: Fix pci_update_current_state
Currently, PCI devices without the PM capability that are power
manageable by the platform (eg. ACPI) are not handled correctly
by pci_set_power_state(), because their current_state field is not
updated to reflect the new power state of the device.  Fix this by
making pci_update_current_state() accept additional argument
representing the power state of the device as set by the platform.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:08 -08:00
Jesse Barnes
eb9c39d031 PCI: set device wakeup capable flag if platform support is present
When PCI devices are initialized, we check whether they support PCI PM
caps and set the device can_wakeup flag if so.  However, some devices
may have platform provided wakeup events rather than PCI PME signals, so
we need to set can_wakeup in that case too.  Doing so should allow
wakeups from many more devices, especially on cost constrained systems.

Reported-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Joseph Chan <JosephChan@via.com.tw>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:07 -08:00
Yu Zhao
613e7ed6f7 PCI: add a new function to map BAR offsets
Add a function to map a given resource number to a corresponding
register so drivers can get the offset and type of device specific BARs.

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-01-07 11:13:04 -08:00