Host bridge hotplug:
- Untangle _PRT from struct pci_bus (Bjorn Helgaas)
- Request _OSC control before scanning root bus (Taku Izumi)
- Assign resources when adding host bridge (Yinghai Lu)
- Remove root bus when removing host bridge (Yinghai Lu)
- Remove _PRT during hot remove (Yinghai Lu)
SRIOV
- Add sysfs knobs to control numVFs (Don Dutile)
Power management
- Notify devices when power resource turned on (Huang Ying)
Bug fixes
- Work around broken _SEG on HP xw9300 (Bjorn Helgaas)
- Keep runtime PM enabled for unbound PCI devices (Huang Ying)
- Fix Optimus dual-GPU runtime D3 suspend issue (Dave Airlie)
- Fix xen frontend shutdown issue (David Vrabel)
- Work around PLX PCI 9050 BAR alignment erratum (Ian Abbott)
Miscellaneous
- Add GPL license for drivers/pci/ioapic (Andrew Cooks)
- Add standard PCI-X, PCIe ASPM register #defines (Bjorn Helgaas)
- NumaChip remote PCI support (Daniel Blueman)
- Fix PCIe Link Capabilities Supported Link Speed definition (Jingoo Han)
- Convert dev_printk() to dev_info(), etc (Joe Perches)
- Add support for non PCI BAR ROM data (Matthew Garrett)
- Add x86 support for host bridge translation offset (Mike Yoknis)
- Report success only when every driver supports AER (Vijay Pandarathil)
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Merge tag 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI update from Bjorn Helgaas:
"Host bridge hotplug:
- Untangle _PRT from struct pci_bus (Bjorn Helgaas)
- Request _OSC control before scanning root bus (Taku Izumi)
- Assign resources when adding host bridge (Yinghai Lu)
- Remove root bus when removing host bridge (Yinghai Lu)
- Remove _PRT during hot remove (Yinghai Lu)
SRIOV
- Add sysfs knobs to control numVFs (Don Dutile)
Power management
- Notify devices when power resource turned on (Huang Ying)
Bug fixes
- Work around broken _SEG on HP xw9300 (Bjorn Helgaas)
- Keep runtime PM enabled for unbound PCI devices (Huang Ying)
- Fix Optimus dual-GPU runtime D3 suspend issue (Dave Airlie)
- Fix xen frontend shutdown issue (David Vrabel)
- Work around PLX PCI 9050 BAR alignment erratum (Ian Abbott)
Miscellaneous
- Add GPL license for drivers/pci/ioapic (Andrew Cooks)
- Add standard PCI-X, PCIe ASPM register #defines (Bjorn Helgaas)
- NumaChip remote PCI support (Daniel Blueman)
- Fix PCIe Link Capabilities Supported Link Speed definition (Jingoo
Han)
- Convert dev_printk() to dev_info(), etc (Joe Perches)
- Add support for non PCI BAR ROM data (Matthew Garrett)
- Add x86 support for host bridge translation offset (Mike Yoknis)
- Report success only when every driver supports AER (Vijay
Pandarathil)"
Fix up trivial conflicts.
* tag 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (48 commits)
PCI: Use phys_addr_t for physical ROM address
x86/PCI: Add NumaChip remote PCI support
ath9k: Use standard #defines for PCIe Capability ASPM fields
iwlwifi: Use standard #defines for PCIe Capability ASPM fields
iwlwifi: collapse wrapper for pcie_capability_read_word()
iwlegacy: Use standard #defines for PCIe Capability ASPM fields
iwlegacy: collapse wrapper for pcie_capability_read_word()
cxgb3: Use standard #defines for PCIe Capability ASPM fields
PCI: Add standard PCIe Capability Link ASPM field names
PCI/portdrv: Use PCI Express Capability accessors
PCI: Use standard PCIe Capability Link register field names
x86: Use PCI setup data
PCI: Add support for non-BAR ROMs
PCI: Add pcibios_add_device
EFI: Stash ROMs if they're not in the PCI BAR
PCI: Add and use standard PCI-X Capability register names
PCI/PM: Keep runtime PM enabled for unbound PCI devices
xen-pcifront: Handle backend CLOSED without CLOSING
PCI: SRIOV control and status via sysfs (documentation)
PCI/AER: Report success only when every device has AER-aware driver
...
For unbound PCI devices, what we need is:
- Always in D0 state, because some devices do not work again after
being put into D3 by the PCI bus.
- In SUSPENDED state if allowed, so that the parent devices can still
be put into low power state.
To satisfy these requirements, the runtime PM for the unbound PCI
devices are disabled and set to SUSPENDED state. One issue of this
solution is that the PCI devices will be put into SUSPENDED state even
if the SUSPENDED state is forbidden via the sysfs interface
(.../power/control) of the device. This is not an issue for most
devices, because most PCI devices are not used at all if unbound.
But there are exceptions. For example, unbound VGA card can be used
for display, but suspending its parents makes it stop working.
To fix the issue, we keep the runtime PM enabled when the PCI devices
are unbound. But the runtime PM callbacks will do nothing if the PCI
devices are unbound. This way, we can put the PCI devices into
SUSPENDED state without putting the PCI devices into D3 state.
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=48201
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org # v3.6+
With the demise of CONFIG_HOTPLUG as an option, the pci_uevent
function located in hotplug.c will now always be used and doesn't need
special treatment in the Makefile. Move pci_uevent into pci-driver.c
and remove hotplug.c
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove conditional code based on CONFIG_HOTPLUG being false. It's
always on now in preparation of it going away as an option.
Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the driver takes care of state saving, don't touch any registers on it.
Optimus (dual-gpu) laptops seem to have their own form of D3cold, but
unfortunately enter it on normal D3 transitions via the ACPI callback.
So when we use runtime PM to transition to D3, the card disappears off
the PCI bus, however we then try to access registers on it in the
runtime suspend finish, which really doesn't work.
This patch checks whether the pci state is saved and doesn't attempt to hit
any registers after that point if it is.
(Looks okay to Rafael)
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Some actions during shutdown need device to be in D0 state, such as
MSI shutdown etc, so resume device before shutdown.
Without this patch, a device may not be enumerated after a kexec
because the corresponding bridge is not in D0, so that
configuration space of the device is not accessible.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CC: stable@vger.kernel.org # v3.6+
* Improved system suspend/resume and runtime PM handling for the SH TMU, CMT
and MTU2 clock event devices (also used by ARM/shmobile).
* Generic PM domains framework extensions related to cpuidle support and
domain objects lookup using names.
* ARM/shmobile power management updates including improved support for the
SH7372's A4S power domain containing the CPU core.
* cpufreq changes related to AMD CPUs support from Matthew Garrett, Andre
Przywara and Borislav Petkov.
* cpu0 cpufreq driver from Shawn Guo.
* cpufreq governor fixes related to the relaxing of limit from Michal Pecio.
* OMAP cpufreq updates from Axel Lin and Richard Zhao.
* cpuidle ladder governor fixes related to the disabling of states from
Carsten Emde and me.
* Runtime PM core updates related to the interactions with the system suspend
core from Alan Stern and Kevin Hilman.
* Wakeup sources modification allowing more helper functions to be called from
interrupt context from John Stultz and additional diagnostic code from Todd
Poynor.
* System suspend error code path fix from Feng Hong.
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Merge tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael J Wysocki:
- Improved system suspend/resume and runtime PM handling for the SH
TMU, CMT and MTU2 clock event devices (also used by ARM/shmobile).
- Generic PM domains framework extensions related to cpuidle support
and domain objects lookup using names.
- ARM/shmobile power management updates including improved support for
the SH7372's A4S power domain containing the CPU core.
- cpufreq changes related to AMD CPUs support from Matthew Garrett,
Andre Przywara and Borislav Petkov.
- cpu0 cpufreq driver from Shawn Guo.
- cpufreq governor fixes related to the relaxing of limit from Michal
Pecio.
- OMAP cpufreq updates from Axel Lin and Richard Zhao.
- cpuidle ladder governor fixes related to the disabling of states from
Carsten Emde and me.
- Runtime PM core updates related to the interactions with the system
suspend core from Alan Stern and Kevin Hilman.
- Wakeup sources modification allowing more helper functions to be
called from interrupt context from John Stultz and additional
diagnostic code from Todd Poynor.
- System suspend error code path fix from Feng Hong.
Fixed up conflicts in cpufreq/powernow-k8 that stemmed from the
workqueue fixes conflicting fairly badly with the removal of support for
hardware P-state chips. The changes were independent but somewhat
intertwined.
* tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (76 commits)
Revert "PM QoS: Use spinlock in the per-device PM QoS constraints code"
PM / Runtime: let rpm_resume() succeed if RPM_ACTIVE, even when disabled, v2
cpuidle: rename function name "__cpuidle_register_driver", v2
cpufreq: OMAP: Check IS_ERR() instead of NULL for omap_device_get_by_hwmod_name
cpuidle: remove some empty lines
PM: Prevent runtime suspend during system resume
PM QoS: Use spinlock in the per-device PM QoS constraints code
PM / Sleep: use resume event when call dpm_resume_early
cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure
ACPI / processor: remove pointless variable initialization
ACPI / processor: remove unused function parameter
cpufreq: OMAP: remove loops_per_jiffy recalculate for smp
sections: fix section conflicts in drivers/cpufreq
cpufreq: conservative: update frequency when limits are relaxed
cpufreq / ondemand: update frequency when limits are relaxed
properly __init-annotate pm_sysrq_init()
cpufreq: Add a generic cpufreq-cpu0 driver
PM / OPP: Initialize OPP table from device tree
ARM: add cpufreq transiton notifier to adjust loops_per_jiffy for smp
cpufreq: Remove support for hardware P-state chips from powernow-k8
...
This patch (as1591) moves the pm_runtime_get_noresume() and
pm_runtime_put_sync() calls from __device_suspend() and
device_resume() to device_prepare() and device_complete() in the PM
core.
The reason for doing this is to make sure that parent devices remain
at full power (i.e., don't go into runtime suspend) while their
children are being resumed from a system sleep.
The PCI core already contained equivalent code to serve the same
purpose. The patch removes the duplicated code, since it is no longer
needed. One of the comments from the PCI core gets moved into the PM
core, and a second comment is added to explain whe the _get_noresume
and _put_sync calls are present.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This patch removes hardcoded sysfs attributes manipulation and
converts them into generic pci_bus->drv_attrs. This saves several bytes.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This patch fixes the following bug:
http://marc.info/?l=linux-pci&m=134329923124234&w=2
The root cause of the bug is as follow.
If a device is not bound with the corresponding driver, the device
runtime PM will be disabled and the device will be put into suspended
state. So that, the bridge/PCIe port connected to it may be put into
suspended and low power state. When do probing for the device later,
because the bridge/PCIe port connected to it is in low power state,
the IO access to device may fail.
To solve the issue, the bridge/PCIe port connected to the device is
put into active state before probing.
Reported-by: Bjorn Mork <bjorn@mork.no>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Commit dbf0e4c (PCI: EHCI: fix crash during suspend on ASUS
computers) added a workaround for an ASUS suspend issue related to
USB EHCI and a bug in a number of ASUS BIOSes that attempt to shut
down the EHCI controller during system suspend if its PCI command
register doesn't contain 0 at that time.
It turns out that the same workaround is necessary in the analogous
hibernation code path, so add it.
References: https://bugzilla.kernel.org/show_bug.cgi?id=45811
Reported-and-tested-by: Oleksij Rempel <bug-track@fisher-privat.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Host bridge hotplug
- Add MMCONFIG support for hot-added host bridges (Jiang Liu)
Device hotplug
- Move fixups from __init to __devinit (Sebastian Andrzej Siewior)
- Call FINAL fixups for hot-added devices, too (Myron Stowe)
- Factor out generic code for P2P bridge hot-add (Yinghai Lu)
- Remove all functions in a slot, not just those with _EJx (Amos Kong)
Dynamic resource management
- Track bus number allocation (struct resource tree per domain) (Yinghai Lu)
- Make P2P bridge 1K I/O windows work with resource reassignment (Bjorn Helgaas, Yinghai Lu)
- Disable decoding while updating 64-bit BARs (Bjorn Helgaas)
Power management
- Add PCIe runtime D3cold support (Huang Ying)
Virtualization
- Add VFIO infrastructure (ACS, DMA source ID quirks) (Alex Williamson)
- Add quirks for devices with broken INTx masking (Jan Kiszka)
Miscellaneous
- Fix some PCI Express capability version issues (Myron Stowe)
- Factor out some arch code with a weak, generic, pcibios_setup() (Myron Stowe)
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Merge tag 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI changes from Bjorn Helgaas:
"Host bridge hotplug:
- Add MMCONFIG support for hot-added host bridges (Jiang Liu)
Device hotplug:
- Move fixups from __init to __devinit (Sebastian Andrzej Siewior)
- Call FINAL fixups for hot-added devices, too (Myron Stowe)
- Factor out generic code for P2P bridge hot-add (Yinghai Lu)
- Remove all functions in a slot, not just those with _EJx (Amos
Kong)
Dynamic resource management:
- Track bus number allocation (struct resource tree per domain)
(Yinghai Lu)
- Make P2P bridge 1K I/O windows work with resource reassignment
(Bjorn Helgaas, Yinghai Lu)
- Disable decoding while updating 64-bit BARs (Bjorn Helgaas)
Power management:
- Add PCIe runtime D3cold support (Huang Ying)
Virtualization:
- Add VFIO infrastructure (ACS, DMA source ID quirks) (Alex
Williamson)
- Add quirks for devices with broken INTx masking (Jan Kiszka)
Miscellaneous:
- Fix some PCI Express capability version issues (Myron Stowe)
- Factor out some arch code with a weak, generic, pcibios_setup()
(Myron Stowe)"
* tag 'for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (122 commits)
PCI: hotplug: ensure a consistent return value in error case
PCI: fix undefined reference to 'pci_fixup_final_inited'
PCI: build resource code for M68K architecture
PCI: pciehp: remove unused pciehp_get_max_lnk_width(), pciehp_get_cur_lnk_width()
PCI: reorder __pci_assign_resource() (no change)
PCI: fix truncation of resource size to 32 bits
PCI: acpiphp: merge acpiphp_debug and debug
PCI: acpiphp: remove unused res_lock
sparc/PCI: replace pci_cfg_fake_ranges() with pci_read_bridge_bases()
PCI: call final fixups hot-added devices
PCI: move final fixups from __init to __devinit
x86/PCI: move final fixups from __init to __devinit
MIPS/PCI: move final fixups from __init to __devinit
PCI: support sizing P2P bridge I/O windows with 1K granularity
PCI: reimplement P2P bridge 1K I/O windows (Intel P64H2)
PCI: disable MEM decoding while updating 64-bit MEM BARs
PCI: leave MEM and IO decoding disabled during 64-bit BAR sizing, too
PCI: never discard enable/suspend/resume_early/resume fixups
PCI: release temporary reference in __nv_msi_ht_cap_quirk()
PCI: restructure 'pci_do_fixups()'
...
Quite a few ASUS computers experience a nasty problem, related to the
EHCI controllers, when going into system suspend. It was observed
that the problem didn't occur if the controllers were not put into the
D3 power state before starting the suspend, and commit
151b612847 (USB: EHCI: fix crash during
suspend on ASUS computers) was created to do this.
It turned out this approach messed up other computers that didn't have
the problem -- it prevented USB wakeup from working. Consequently
commit c2fb8a3fa2 (USB: add
NO_D3_DURING_SLEEP flag and revert 151b612847) was merged; it
reverted the earlier commit and added a whitelist of known good board
names.
Now we know the actual cause of the problem. Thanks to AceLan Kao for
tracking it down.
According to him, an engineer at ASUS explained that some of their
BIOSes contain a bug that was added in an attempt to work around a
problem in early versions of Windows. When the computer goes into S3
suspend, the BIOS tries to verify that the EHCI controllers were first
quiesced by the OS. Nothing's wrong with this, but the BIOS does it
by checking that the PCI COMMAND registers contain 0 without checking
the controllers' power state. If the register isn't 0, the BIOS
assumes the controller needs to be quiesced and tries to do so. This
involves making various MMIO accesses to the controller, which don't
work very well if the controller is already in D3. The end result is
a system hang or memory corruption.
Since the value in the PCI COMMAND register doesn't matter once the
controller has been suspended, and since the value will be restored
anyway when the controller is resumed, we can work around the BIOS bug
simply by setting the register to 0 during system suspend. This patch
(as1590) does so and also reverts the second commit mentioned above,
which is now unnecessary.
In theory we could do this for every PCI device. However to avoid
introducing new problems, the patch restricts itself to EHCI host
controllers.
Finally the affected systems can suspend with USB wakeup working
properly.
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=37632
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=42728
Based-on-patch-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Dâniel Fraga <fragabr@gmail.com>
Tested-by: Javier Marcet <jmarcet@gmail.com>
Tested-by: Andrey Rahmatullin <wrar@wrar.name>
Tested-by: Oleksij Rempel <bug-track@fisher-privat.net>
Tested-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Cc: stable <stable@vger.kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit cc2893b6 (PCI: Ensure we re-enable devices on resume)
addressed the problem with USB not being powered after resume on
recent Lenovo machines, but it did that in a suboptimal way.
Namely, it should have changed the relevant code paths only,
which are pci_pm_resume_noirq() and pci_pm_restore_noirq() supposed
to restore the device's power and standard configuration registers
after system resume from suspend or hibernation. Instead, however,
it modified pci_set_power_state() which is executed in several
other situations too. That resulted in some undesirable effects,
like attempting to change a device's power state in the same way
multiple times in a row (up to as many as 4 times in a row in the
snd_hda_intel driver).
Fix the bug addressed by commit cc2893b6 in an alternative way,
by forcibly powering up all devices in pci_pm_default_resume_early(),
which is called by pci_pm_resume_noirq() and pci_pm_restore_noirq()
to restore the device's power and standard configuration registers,
and modifying pci_pm_runtime_resume() to avoid the forcible power-up
if not necessary. Then, revert the changes made by commit cc2893b6
to make the confusion introduced by it go away.
Acked-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This patch adds runtime D3cold support and corresponding ACPI platform
support. This patch only enables runtime D3cold support; it does not
enable D3cold support during system suspend/hibernate.
D3cold is the deepest power saving state for a PCIe device, where its main
power is removed. While it is in D3cold, you can't access the device at
all, not even its configuration space (which is still accessible in D3hot).
Therefore the PCI PM registers can not be used to transition into/out of
the D3cold state; that must be done by platform logic such as ACPI _PR3.
To support wakeup from D3cold, a system may provide auxiliary power, which
allows a device to request wakeup using a Beacon or the sideband WAKE#
signal. WAKE# is usually connected to platform logic such as ACPI GPE.
This is quite different from other power saving states, where devices
request wakeup via a PME message on the PCIe link.
Some devices, such as those in plug-in slots, have no direct platform
logic. For example, there is usually no ACPI _PR3 for them. D3cold
support for these devices can be done via the PCIe Downstream Port leading
to the device. When the PCIe port is powered on/off, the device is powered
on/off too. Wakeup events from the device will be notified to the
corresponding PCIe port.
For more information about PCIe D3cold and corresponding ACPI support,
please refer to:
- PCI Express Base Specification Revision 2.0
- Advanced Configuration and Power Interface Specification Revision 5.0
[bhelgaas: changelog]
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Originally-by: Zheng Yan <zheng.z.yan@intel.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Disable Bus Master bit on the device in pci_device_shutdown() to ensure PCI
devices do not continue to DMA data after shutdown. This can cause memory
corruption in case of a kexec where the current kernel shuts down and
transfers control to a new kernel while a PCI device continues to DMA to
memory that does not belong to it any more in the new kernel.
I have tested this code on two laptops, two workstations and a 16-socket
server. kexec worked correctly on all of them.
Signed-off-by: Khalid Aziz <khalid.aziz@hp.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Pull PCI changes (including maintainer change) from Jesse Barnes:
"This pull has some good cleanups from Bjorn and Yinghai, as well as
some more code from Yinghai to better handle resource re-allocation
when enabled.
There's also a new initcall_debug feature from Arjan which will print
out quirk timing information to help identify slow quirks for fixing
or refinement (Yinghai sent in a few patches to do just that once the
new debug code landed).
Beyond that, I'm handing off PCI maintainership to Bjorn Helgaas.
He's been a core PCI and Linux contributor for some time now, and has
kindly volunteered to take over. I just don't feel I have the time
for PCI review and work that it deserves lately (I've taken on some
other projects), and haven't been as responsive lately as I'd like, so
I approached Bjorn asking if he'd like to manage things. He's going
to give it a try, and I'm confident he'll do at least as well as I
have in keeping the tree managed, patches flowing, and keeping things
stable."
Fix up some fairly trivial conflicts due to other cleanups (mips device
resource fixup cleanups clashing with list handling cleanup, ppc iseries
removal clashing with pci_probe_only cleanup etc)
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci: (112 commits)
PCI: Bjorn gets PCI hotplug too
PCI: hand PCI maintenance over to Bjorn Helgaas
unicore32/PCI: move <asm-generic/pci-bridge.h> include to asm/pci.h
sparc/PCI: convert devtree and arch-probed bus addresses to resource
powerpc/PCI: allow reallocation on PA Semi
powerpc/PCI: convert devtree bus addresses to resource
powerpc/PCI: compute I/O space bus-to-resource offset consistently
arm/PCI: don't export pci_flags
PCI: fix bridge I/O window bus-to-resource conversion
x86/PCI: add spinlock held check to 'pcibios_fwaddrmap_lookup()'
PCI / PCIe: Introduce command line option to disable ARI
PCI: make acpihp use __pci_remove_bus_device instead
PCI: export __pci_remove_bus_device
PCI: Rename pci_remove_behind_bridge to pci_stop_and_remove_behind_bridge
PCI: Rename pci_remove_bus_device to pci_stop_and_remove_bus_device
PCI: print out PCI device info along with duration
PCI: Move "pci reassigndev resource alignment" out of quirks.c
PCI: Use class for quirk for usb host controller fixup
PCI: Use class for quirk for ti816x class fixup
PCI: Use class for quirk for intel e100 interrupt fixup
...
If a PCI device is enabled to generate wakeup signals (PME) when put
into a low-power state by runtime PM, it will be still enabled to
generate those signals after the system shutdown, unless its driver's
.shutdown() callback takes care of the wakeup signals generation
setting. Moreover, there are devices that are not enabled to wake
up the system and that are configured by runtime PM to generate
wakeup signals so that (runtime) remote wakeup works with them.
Those devices should be reconfigured during system shutdown so that
they don't generate wakeup signals, but at least some drivers don't
do that. However, that very well may be done by the PCI core so
that drivers don't have to worry about it. For this reason, modify
pci_device_shutdown() to disable the generation of wakeup events for
devices not supposed to wake up the system.
References: https://bugzilla.kernel.org/show_bug.cgi?id=37952
Reported-and-tested-by: Kamil Iskra <kamil.54002@iskra.name>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch (as1514) cleans up some places where new_id and remove_id
sysfs attributes are created and deleted. Handling both attributes in
a single routine rather than a pair of routines makes the code
smaller. It also prevents certain kinds of errors, like one we
currently have in the USB subsystem: The removeid attribute is often
created even when newid isn't (because the driver's no_dynamid_id flag
is set).
In the case of the PCMCIA subsystem, the newid attribute is created
but never explicitly deleted. The patch adds a deletion routine.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As part of the removal of get_driver()/put_driver(), this patch
(as1511) changes all the places that add dynamic IDs for drivers.
Since these additions are done by writing to the drivers' sysfs
attribute files, and the attributes are removed when the drivers are
unregistered, there is no reason to take an extra reference to the
drivers.
The one exception is the pci-stub driver, which calls pci_add_dynid()
as part of its registration. But again, there's no reason to take an
extra reference here, because the driver can't be unloaded while it is
being registered.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Dmitry Torokhov <dmitry.torokhov@gmail.com>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Include the driver name and device in warning when a pci driver
supports both legacy pm and new framework as just the stack trace
gives no way to identify the driver.
Signed-off-by: David Fries <David@Fries.net>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
A subsequent patch is going to move the invocation of
pm_runtime_barrier() from dpm_prepare() to __device_suspend().
Consequently, early wakeup events resulting from runtime resume
requests for wakeup devices queued up right before system suspend
will only be detected after all of the subsystem-level .prepare()
callbacks have run. However, the PCI bus type calls
pm_runtime_get_sync() from its pci_pm_prepare() callback routine,
so it would destroy the early wakeup events information regarding PCI
devices. To prevent this from happening add an early wakeup
detection mechanism, analogous to the one currently in dpm_prepare(),
to pci_pm_prepare().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
After commit e866500247
(PM: Allow pm_runtime_suspend() to succeed during system suspend) it
is possible that a device resumed by the pm_runtime_resume(dev) in
pci_pm_prepare() will be suspended immediately from a work item,
timer function or otherwise, defeating the very purpose of calling
pm_runtime_resume(dev) from there. To prevent that from happening
it is necessary to increment the runtime PM usage counter of the
device by replacing pm_runtime_resume() with pm_runtime_get_sync().
Moreover, the incremented runtime PM usage counter has to be
decremented by the corresponding pci_pm_complete(), via
pm_runtime_put_sync().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: stable@kernel.org
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Xen save/restore is going to use hibernate device callbacks for
quiescing devices and putting them back to normal operations and it
would need to select CONFIG_HIBERNATION for this purpose. However,
that also would cause the hibernate interfaces for user space to be
enabled, which might confuse user space, because the Xen kernels
don't support hibernation. Moreover, it would be wasteful, as it
would make the Xen kernels include a substantial amount of code that
they would never use.
To address this issue introduce new power management Kconfig option
CONFIG_HIBERNATE_CALLBACKS, such that it will only select the code
that is necessary for the hibernate device callbacks to work and make
CONFIG_HIBERNATION select it. Then, Xen save/restore will be able to
select CONFIG_HIBERNATE_CALLBACKS without dragging the entire
hibernate code along with it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
After redefining CONFIG_PM to depend on (CONFIG_PM_SLEEP ||
CONFIG_PM_RUNTIME) the CONFIG_PM_OPS option is redundant and can be
replaced with CONFIG_PM.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
pci_restore_state only ever returns 0, thus there is no benefit in
having it return any value. Also, a large majority of the callers do
not check the return code of pci_restore_state. Make the
pci_restore_state a void return and avoid the overhead.
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Jon Mason <jon.mason@exar.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch (as1388) changes the way the PCI core handles runtime PM
settings when probing or unbinding drivers. Now the core will make
sure the device is enabled for runtime PM, with a usage count >= 1,
when a driver is probed. It does the same when calling a driver's
remove method.
If the driver wants to use runtime PM, all it has to do is call
pm_runtime_pu_noidle() near the end of its probe routine (to cancel
the core's usage increment) and pm_runtime_get_noresume() near the
start of its remove routine (to restore the usage count). It does not
need to mess around with setting the runtime state to enabled,
disabled, active, or suspended.
The patch updates e1000e and r8169, the only PCI drivers that already
use the existing runtime PM interface.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse 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: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (75 commits)
PCI hotplug: clean up acpi_run_hpp()
PCI hotplug: acpiphp: use generic pci_configure_slot()
PCI hotplug: shpchp: use generic pci_configure_slot()
PCI hotplug: pciehp: use generic pci_configure_slot()
PCI hotplug: add pci_configure_slot()
PCI hotplug: clean up acpi_get_hp_params_from_firmware() interface
PCI hotplug: acpiphp: don't cache hotplug_params in acpiphp_bridge
PCI hotplug: acpiphp: remove superfluous _HPP/_HPX evaluation
PCI: Clear saved_state after the state has been restored
PCI PM: Return error codes from pci_pm_resume()
PCI: use dev_printk in quirk messages
PCI / PCIe portdrv: Fix pcie_portdrv_slot_reset()
PCI Hotplug: convert acpi_pci_detect_ejectable() to take an acpi_handle
PCI Hotplug: acpiphp: find bridges the easy way
PCI: pcie portdrv: remove unused variable
PCI / ACPI PM: Propagate wake-up enable for devices w/o ACPI support
ACPI PM: Replace wakeup.prepared with reference counter
PCI PM: Introduce device flag wakeup_prepared
PCI / ACPI PM: Rework some debug messages
PCI PM: Simplify PCI wake-up code
...
Fixed up conflict in arch/powerpc/kernel/pci_64.c due to OF device tree
scanning having been moved and merged for the 32- and 64-bit cases. The
'needs_freset' initialization added in 6e19314cc ("PCI/powerpc: support
PCIe fundamental reset") is now in arch/powerpc/kernel/pci_of_scan.c.
Some PCI devices fail if their standard configuration registers are
restored twice in a row. Prevent this from happening by making
pci_restore_state() clear the saved_state flag of the device right
after the device's standard configuration registers have been
populated with the previously saved values.
Simplify PCI PM callbacks by removing the direct clearing of
state_saved from them, as it shouldn't be necessary any more (except
in pci_pm_thaw(), where it has to be cleared, so that the values saved
during the "freeze" phase of hibernation are not used later by mistake).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Currently pci_pm_resume() always returns 0, which makes the error
variable defined in there a bit pointless. Make pci_pm_resume()
return error codes obtained from drivers' callbacks.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse 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: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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>
They are not supposed to be modified by drivers, so make them const.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask: (36 commits)
cpumask: remove cpumask allocation from idle_balance, fix
numa, cpumask: move numa_node_id default implementation to topology.h, fix
cpumask: remove cpumask allocation from idle_balance
x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus
x86: cpumask: update 32-bit APM not to mug current->cpus_allowed
x86: microcode: cleanup
x86: cpumask: use work_on_cpu in arch/x86/kernel/microcode_core.c
cpumask: fix CONFIG_CPUMASK_OFFSTACK=y cpu hotunplug crash
numa, cpumask: move numa_node_id default implementation to topology.h
cpumask: convert node_to_cpumask_map[] to cpumask_var_t
cpumask: remove x86 cpumask_t uses.
cpumask: use cpumask_var_t in uv_flush_tlb_others.
cpumask: remove cpumask_t assignment from vector_allocation_domain()
cpumask: make Xen use the new operators.
cpumask: clean up summit's send_IPI functions
cpumask: use new cpumask functions throughout x86
x86: unify cpu_callin_mask/cpu_callout_mask/cpu_initialized_mask/cpu_sibling_setup_mask
cpumask: convert struct cpuinfo_x86's llc_shared_map to cpumask_var_t
cpumask: convert node_to_cpumask_map[] to cpumask_var_t
x86: unify 32 and 64-bit node_to_cpumask_map
...
* '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
At present the configuration spaces of PCI devices that have no
drivers or no PM support in the drivers (either legacy or through a
pm object) are not saved during suspend and, consequently, they are
not restored during resume. This generally may lead to the state of
the system being slightly inconsistent after the resume, so it's
better to save and restore the configuration spaces of these devices
as well.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Once we have allowed timer interrupts to be enabled during the late
phase of suspending devices, we are now able to use the generic
pci_set_power_state() to put PCI devices into low power states at
that time. We can also use some related platform callbacks, like the
ones preparing devices for wake-up, during the late suspend.
Doing this will allow us to avoid the race condition where a device
using shared interrupts is put into a low power state with interrupts
enabled and then an interrupt (for another device) comes in and
confuses its driver. At the same time, devices that don't support
the native PCI PM or that require some additional, platform-specific
operations to be carried out to put them into low power states will
be handled as appropriate.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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>
I noticed two functions use a variable "i" to store the return value of PM
function calls while the rest of the file uses "error". As "i" normally
indicates a counter of some sort it seems better to keep this consistent.
Signed-off-by: Frans Pop <elendil@planet.nl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This interface allows the user to force a rescan of all PCI buses
in system, and rediscover devices that have been removed earlier.
pci_bus_attrs implementation from Trent Piepho.
Thanks to Vegard Nossum for discovering locking issues with the
sysfs interface.
Cc: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This adds a remove_id sysfs entry to allow users of new_id to later
remove the added dynid. One use case is management tools that want to
dynamically bind/unbind devices to pci-stub driver while devices are
assigned to KVM guests. Rather than having to track which driver was
originally bound to the driver, a mangement tool can simply:
Guest uses device
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: cleanup
node_to_cpumask (and the blecherous node_to_cpumask_ptr which
contained a declaration) are replaced now everyone implements
cpumask_of_node.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently, the PM core always attempts to manage devices with drivers
that use the new PM framework. In particular, it attempts to disable
the devices (which is unnecessary), to save their state (which may be
undesirable if the driver has done that already) and to put them into
low power states (again, this may be undesirable if the driver has
already put the device into a low power state). That need not be
the right thing to do, so make the core be more careful in this
respect.
Generally, there are the following categories of devices to consider:
* bridge devices without drivers
* non-bridge devices without drivers
* bridge devices with drivers
* non-bridge devices with drivers
and each of them should be handled differently.
For bridge devices without drivers the PCI PM core will save their
state on suspend and restore it (early) during resume, after putting
them into D0 if necessary. It will not attempt to do anything else
to these devices.
For non-bridge devices without drivers the PCI PM core will disable
them and save their state on suspend. During resume, it will put
them into D0, if necessary, restore their state (early) and reenable
them.
For bridge devices with drivers the PCI PM core will only save
their state on suspend if the driver hasn't done that already.
Still, the core will restore their state (early) during resume,
after putting them into D0, if necessary.
For non-bridge devices with drivers the PCI PM core will only save
their state on suspend if the driver hasn't done that already. Also,
if the state of the device hasn't been saved by the driver, the core
will attempt to put the device into a low power state. During
resume the core will restore the state of the device (early), after
putting it into D0, if necessary.
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>
Linus Torvalds