The WARN_ON() in acpiphp_enumerate_slots() triggers unnecessarily for
devices whose bridges are going to be handled by native PCIe hotplug
(pciehp) and the simplest way to prevent that from happening is to
drop the WARN_ON().
References: https://bugzilla.kernel.org/show_bug.cgi?id=62831
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
One of the error code paths in acpiphp_enumerate_slots() is missing
a pci_dev_put(bridge->pci_dev) call, so add it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
* acpi-pci-hotplug:
ACPI / hotplug / PCI: Avoid parent bus rescans on spurious device checks
ACPI / hotplug / PCI: Use _OST to notify firmware about notify status
ACPI / hotplug / PCI: Avoid doing too much for spurious notifies
ACPI / hotplug / PCI: Don't trim devices before scanning the namespace
In the current ACPIPHP notify handler we always go directly for a
rescan of the parent bus if we get a device check notification for
a device that is not a bridge. However, this obviously is
overzealous if nothing really changes, because this way we may rescan
the whole PCI hierarchy pretty much in vain.
That happens on Alex Williamson's machine whose ACPI tables contain
device objects that are supposed to coresspond to PCIe root ports,
but those ports aren't physically present (or at least they aren't
visible in the PCI config space to us). The BIOS generates multiple
device check notifies for those objects during boot and for each of
them we go straight for the parent bus rescan, but the parent bus is
the root bus in this particular case. In consequence, we rescan the
whole PCI bus from the top several times in a row, which is
completely unnecessary, increases boot time by 50% (after previous
fixes) and generates excess dmesg output from the PCI subsystem.
Fix the problem by checking if we can find anything new in the
slot corresponding to the device we've got a device check notify
for and doing nothig if that's not the case.
The spec (ACPI 5.0, Section 5.6.6) appears to mandate this behavior,
as it says:
Device Check. Used to notify OSPM that the device either appeared
or disappeared. If the device has appeared, OSPM will re-enumerate
from the parent. If the device has disappeared, OSPM will
invalidate the state of the device. OSPM may optimize out
re-enumeration.
Therefore, according to the spec, we are free to do nothing if
nothing changes.
References: https://bugzilla.kernel.org/show_bug.cgi?id=60865
Reported-and-tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The spec suggests that we should use _OST to notify the platform
about the status of notifications it sends us, for example so that
it doesn't repeate a notification that has been handled already.
This turns out to help reduce the amount of diagnostic output from
the ACPIPHP subsystem and speed up boot on at least one system that
generates multiple device check notifies for PCIe devices on the root
bus during boot.
Reported-and-tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Sometimes we may get a spurious device check or bus check notify for
a hotplug device and in those cases we should avoid doing all of the
configuration work needed when something actually changes. To that
end, check the return value of pci_scan_slot() in enable_slot() and
bail out early if it is 0.
This turns out to help reduce the amount of diagnostic output from
the ACPIPHP subsystem and speed up boot on at least one system that
generates multiple device check notifies for PCIe devices on the root
bus during boot.
Reported-and-tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In acpiphp_bus_add() we first remove device objects corresponding to
the given handle and the ACPI namespace branch below it, which are
then re-created by acpi_bus_scan(). This used to be done to clean
up after surprise removals, but now we do the cleanup through
trim_stale_devices() which checks if the devices in question are
actually gone before removing them, so the device hierarchy trimming
in acpiphp_bus_add() is not necessary any more and, moreover, it may
lead to problems if it removes device objects corresponding to
devices that are actually present.
For this reason, remove the leftover acpiphp_bus_trim() from
acpiphp_bus_add().
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
1) ACPI-based PCI hotplug (ACPIPHP) subsystem rework and introduction
of Intel Thunderbolt support on systems that use ACPI for signalling
Thunderbolt hotplug events. This also should make ACPIPHP work in
some cases in which it was known to have problems. From
Rafael J Wysocki, Mika Westerberg and Kirill A Shutemov.
2) ACPI core code cleanups and dock station support cleanups from
Jiang Liu and Rafael J Wysocki.
3) Fixes for locking problems related to ACPI device hotplug from
Rafael J Wysocki.
4) ACPICA update to version 20130725 includig fixes, cleanups, support
for more than 256 GPEs per GPE block and a change to make the ACPI
PM Timer optional (we've seen systems without the PM Timer in the
field already). One of the fixes, related to the DeRefOf operator,
is necessary to prevent some Windows 8 oriented AML from causing
problems to happen. From Bob Moore, Lv Zheng, and Jung-uk Kim.
5) Removal of the old and long deprecated /proc/acpi/event interface
and related driver changes from Thomas Renninger.
6) ACPI and Xen changes to make the reduced hardware sleep work with
the latter from Ben Guthro.
7) ACPI video driver cleanups and a blacklist of systems that should
not tell the BIOS that they are compatible with Windows 8 (or ACPI
backlight and possibly other things will not work on them). From
Felipe Contreras.
8) Assorted ACPI fixes and cleanups from Aaron Lu, Hanjun Guo,
Kuppuswamy Sathyanarayanan, Lan Tianyu, Sachin Kamat, Tang Chen,
Toshi Kani, and Wei Yongjun.
9) cpufreq ondemand governor target frequency selection change to
reduce oscillations between min and max frequencies (essentially,
it causes the governor to choose target frequencies proportional
to load) from Stratos Karafotis.
10) cpufreq fixes allowing sysfs attributes file permissions to be
preserved over suspend/resume cycles Srivatsa S Bhat.
11) Removal of Device Tree parsing for CPU device nodes from multiple
cpufreq drivers that required some changes related to
of_get_cpu_node() to be made in a few architectures and in the
driver core. From Sudeep KarkadaNagesha.
12) cpufreq core fixes and cleanups related to mutual exclusion and
driver module references from Viresh Kumar, Lukasz Majewski and
Rafael J Wysocki.
13) Assorted cpufreq fixes and cleanups from Amit Daniel Kachhap,
Bartlomiej Zolnierkiewicz, Hanjun Guo, Jingoo Han, Joseph Lo,
Julia Lawall, Li Zhong, Mark Brown, Sascha Hauer, Stephen Boyd,
Stratos Karafotis, and Viresh Kumar.
14) Fixes to prevent race conditions in coupled cpuidle from happening
from Colin Cross.
15) cpuidle core fixes and cleanups from Daniel Lezcano and
Tuukka Tikkanen.
16) Assorted cpuidle fixes and cleanups from Daniel Lezcano,
Geert Uytterhoeven, Jingoo Han, Julia Lawall, Linus Walleij,
and Sahara.
17) System sleep tracing changes from Todd E Brandt and Shuah Khan.
18) PNP subsystem conversion to using struct dev_pm_ops for power
management from Shuah Khan.
/
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Merge tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
1) ACPI-based PCI hotplug (ACPIPHP) subsystem rework and introduction
of Intel Thunderbolt support on systems that use ACPI for signalling
Thunderbolt hotplug events. This also should make ACPIPHP work in
some cases in which it was known to have problems. From
Rafael J Wysocki, Mika Westerberg and Kirill A Shutemov.
2) ACPI core code cleanups and dock station support cleanups from
Jiang Liu and Rafael J Wysocki.
3) Fixes for locking problems related to ACPI device hotplug from
Rafael J Wysocki.
4) ACPICA update to version 20130725 includig fixes, cleanups, support
for more than 256 GPEs per GPE block and a change to make the ACPI
PM Timer optional (we've seen systems without the PM Timer in the
field already). One of the fixes, related to the DeRefOf operator,
is necessary to prevent some Windows 8 oriented AML from causing
problems to happen. From Bob Moore, Lv Zheng, and Jung-uk Kim.
5) Removal of the old and long deprecated /proc/acpi/event interface
and related driver changes from Thomas Renninger.
6) ACPI and Xen changes to make the reduced hardware sleep work with
the latter from Ben Guthro.
7) ACPI video driver cleanups and a blacklist of systems that should
not tell the BIOS that they are compatible with Windows 8 (or ACPI
backlight and possibly other things will not work on them). From
Felipe Contreras.
8) Assorted ACPI fixes and cleanups from Aaron Lu, Hanjun Guo,
Kuppuswamy Sathyanarayanan, Lan Tianyu, Sachin Kamat, Tang Chen,
Toshi Kani, and Wei Yongjun.
9) cpufreq ondemand governor target frequency selection change to
reduce oscillations between min and max frequencies (essentially,
it causes the governor to choose target frequencies proportional
to load) from Stratos Karafotis.
10) cpufreq fixes allowing sysfs attributes file permissions to be
preserved over suspend/resume cycles Srivatsa S Bhat.
11) Removal of Device Tree parsing for CPU device nodes from multiple
cpufreq drivers that required some changes related to
of_get_cpu_node() to be made in a few architectures and in the
driver core. From Sudeep KarkadaNagesha.
12) cpufreq core fixes and cleanups related to mutual exclusion and
driver module references from Viresh Kumar, Lukasz Majewski and
Rafael J Wysocki.
13) Assorted cpufreq fixes and cleanups from Amit Daniel Kachhap,
Bartlomiej Zolnierkiewicz, Hanjun Guo, Jingoo Han, Joseph Lo,
Julia Lawall, Li Zhong, Mark Brown, Sascha Hauer, Stephen Boyd,
Stratos Karafotis, and Viresh Kumar.
14) Fixes to prevent race conditions in coupled cpuidle from happening
from Colin Cross.
15) cpuidle core fixes and cleanups from Daniel Lezcano and
Tuukka Tikkanen.
16) Assorted cpuidle fixes and cleanups from Daniel Lezcano,
Geert Uytterhoeven, Jingoo Han, Julia Lawall, Linus Walleij,
and Sahara.
17) System sleep tracing changes from Todd E Brandt and Shuah Khan.
18) PNP subsystem conversion to using struct dev_pm_ops for power
management from Shuah Khan.
* tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (217 commits)
cpufreq: Don't use smp_processor_id() in preemptible context
cpuidle: coupled: fix race condition between pokes and safe state
cpuidle: coupled: abort idle if pokes are pending
cpuidle: coupled: disable interrupts after entering safe state
ACPI / hotplug: Remove containers synchronously
driver core / ACPI: Avoid device hot remove locking issues
cpufreq: governor: Fix typos in comments
cpufreq: governors: Remove duplicate check of target freq in supported range
cpufreq: Fix timer/workqueue corruption due to double queueing
ACPI / EC: Add ASUSTEK L4R to quirk list in order to validate ECDT
ACPI / thermal: Add check of "_TZD" availability and evaluating result
cpufreq: imx6q: Fix clock enable balance
ACPI: blacklist win8 OSI for buggy laptops
cpufreq: tegra: fix the wrong clock name
cpuidle: Change struct menu_device field types
cpuidle: Add a comment warning about possible overflow
cpuidle: Fix variable domains in get_typical_interval()
cpuidle: Fix menu_device->intervals type
cpuidle: CodingStyle: Break up multiple assignments on single line
cpuidle: Check called function parameter in get_typical_interval()
...
Add an arch specific attribute to recover a pci function from an
error state or config space blockage.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Convert s390' pci hotplug to be builtin only, with no module option.
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* acpi-pci-hotplug: (34 commits)
ACPI / PM: Hold acpi_scan_lock over system PM transitions
ACPI / hotplug / PCI: Fix NULL pointer dereference in cleanup_bridge()
PCI / ACPI: Use dev_dbg() instead of dev_info() in acpi_pci_set_power_state()
ACPI / hotplug / PCI: Get rid of check_sub_bridges()
ACPI / hotplug / PCI: Clean up bridge_mutex usage
ACPI / hotplug / PCI: Redefine enable_device() and disable_device()
ACPI / hotplug / PCI: Sanitize acpiphp_get_(latch)|(adapter)_status()
ACPI / hotplug / PCI: Get rid of unused constants in acpiphp.h
ACPI / hotplug / PCI: Check for new devices on enabled slots
ACPI / hotplug / PCI: Allow slots without new devices to be rescanned
ACPI / hotplug / PCI: Do not check SLOT_ENABLED in enable_device()
ACPI / hotplug / PCI: Do not exectute _PS0 and _PS3 directly
ACPI / hotplug / PCI: Do not queue up event handling work items in vain
ACPI / hotplug / PCI: Consolidate slot disabling and ejecting
ACPI / hotplug / PCI: Drop redundant checks from check_hotplug_bridge()
ACPI / hotplug / PCI: Rework namespace scanning and trimming routines
ACPI / hotplug / PCI: Store parent in functions and bus in slots
ACPI / hotplug / PCI: Drop handle field from struct acpiphp_bridge
ACPI / hotplug / PCI: Drop handle field from struct acpiphp_func
ACPI / hotplug / PCI: Embed function struct into struct acpiphp_context
...
* acpi-cleanup: (21 commits)
ACPI / dock: fix error return code in dock_add()
ACPI / dock: Drop unnecessary local variable from dock_add()
ACPI / dock / PCI: Drop ACPI dock notifier chain
ACPI / dock: Do not check CONFIG_ACPI_DOCK_MODULE
ACPI / dock: Do not leak memory on falilures to add a dock station
ACPI: Drop ACPI bus notifier call chain
ACPI / dock: Rework the handling of notifications
ACPI / dock: Simplify dock_init_hotplug() and dock_release_hotplug()
ACPI / dock: Walk list in reverse order during removal of devices
ACPI / dock: Rework and simplify find_dock_devices()
ACPI / dock: Drop the hp_lock mutex from struct dock_station
ACPI: simplify acpiphp driver with new helper functions
ACPI: simplify dock driver with new helper functions
ACPI: Export acpi_(bay)|(dock)_match() from scan.c
ACPI: introduce two helper functions for _EJ0 and _LCK
ACPI: introduce helper function acpi_execute_simple_method()
ACPI: introduce helper function acpi_has_method()
ACPI / dock: simplify dock_create_acpi_device()
ACPI / dock: mark initialization functions with __init
ACPI / dock: drop redundant spin lock in dock station object
...
* pci/yinghai-assign-unassigned-v6:
PCI: Assign resources for hot-added host bridge more aggressively
PCI: Move resource reallocation code to non-__init
PCI: Delay enabling bridges until they're needed
PCI: Assign resources on a per-bus basis
PCI: Enable unassigned resource reallocation on per-bus basis
PCI: Turn on reallocation for unassigned resources with host bridge offset
PCI: Look for unassigned resources on per-bus basis
PCI: Drop temporary variable in pci_assign_unassigned_resources()
Based on a patch by Jon Mason (see URL below).
All users of pcie_bus_configure_settings() pass arguments of the form
"bus, bus->self->pcie_mpss". The "mpss" argument is redundant since we
can easily look it up internally. In addition, all callers check
"bus->self" for NULL, which we can also do internally.
This patch simplifies the interface and the callers. No functional change.
Reference: http://lkml.kernel.org/r/1317048850-30728-2-git-send-email-mason@myri.com
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
After commit bbd34fc (ACPI / hotplug / PCI: Register all devices
under the given bridge) register_slot() is called for all PCI
devices under a given bridge that have corresponding objects in
the ACPI namespace, but it calls acpiphp_register_hotplug_slot()
only for devices satisfying specific criteria. Still,
cleanup_bridge() calls acpiphp_unregister_hotplug_slot() for all
objects created by register_slot(), although it should only call it
for the ones that acpiphp_register_hotplug_slot() has been called
for (successfully). This causes a NULL pointer to be dereferenced
by the acpiphp_unregister_hotplug_slot() executed by cleanup_bridge()
if the object it is called for has not been passed to
acpiphp_register_hotplug_slot().
To fix this problem, check if the 'slot' field of the object passed
to acpiphp_unregister_hotplug_slot() in cleanup_bridge() is not NULL,
which only is the case if acpiphp_register_hotplug_slot() has been
executed for that object. In addition to that, make register_slot()
reset the 'slot' field to NULL if acpiphp_register_hotplug_slot() has
failed for the given object to prevent stale pointers from being
used by acpiphp_unregister_hotplug_slot().
Reported-and-tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PCIe hotplug has a bus per slot, so we can just use a normal
secondary bus reset. However, if a slot supports surprise removal,
a bus reset can be seen as a presence detection change triggering
a hot-remove followed by a hot-add. Disable presence detection from
triggering an interrupt or being polled around the bus reset.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Hotplug
PCI: pciehp: Fix null pointer deref when hot-removing SR-IOV device
PCI: hotplug: Convert to be builtin only, not modular
PCI: pciehp: Convert pciehp to be builtin only, not modular
Resource allocation
PCI: Retry allocation of only the resource type that failed
ARM
PCI: mvebu: Disable prefetchable memory support in PCI-to-PCI bridge
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Merge tag 'pci-v3.11-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI fixes from Bjorn Helgaas:
"Yinghai fixed a couple regressions: one resource assignment problem
introduced in v3.10 that showed up with SR-IOV on powerpc, and another
SR-IOV hot-remove issue related to refcounting changes we merged for
v3.11.
Yinghai is still working on another SR-IOV-related fix or two, which
will be simpler if pciehp is non-modular, so I included the Kconfig
changes now to get them in earlier.
Finally, a minor fix for the ARM Marvell EBU host bridge driver that
was merged for v3.11
Hotplug:
PCI: pciehp: Fix null pointer deref when hot-removing SR-IOV device
PCI: hotplug: Convert to be builtin only, not modular
PCI: pciehp: Convert pciehp to be builtin only, not modular
Resource allocation:
PCI: Retry allocation of only the resource type that failed
ARM:
PCI: mvebu: Disable prefetchable memory support in PCI-to-PCI bridge"
* tag 'pci-v3.11-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: mvebu: Disable prefetchable memory support in PCI-to-PCI bridge
PCI: Retry allocation of only the resource type that failed
PCI: pciehp: Convert pciehp to be builtin only, not modular
PCI: hotplug: Convert to be builtin only, not modular
PCI: pciehp: Fix null pointer deref when hot-removing SR-IOV device
Convert CONFIG_HOTPLUG_PCI from tristate to bool. This only affects
the hotplug core; several of the hotplug drivers can still be modules.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Hot-removing a device with SR-IOV enabled causes a null pointer dereference
in v3.9 and v3.10.
This is a regression caused by ba518e3c17 ("PCI: pciehp: Iterate over all
devices in slot, not functions 0-7"). When we iterate over the
bus->devices list, we first remove the PF, which also removes all the VFs
from the list. Then the list iterator blows up because more than just the
current entry was removed from the list.
ac205b7bb7 ("PCI: make sriov work with hotplug remove") works around a
similar problem in pci_stop_bus_devices() by iterating over the list in
reverse, so the VFs are stopped and removed from the list first, before the
PF.
This patch changes pciehp_unconfigure_device() to iterate over the list in
reverse, too.
[bhelgaas: bugzilla, changelog]
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=60604
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yijing Wang <wangyijing@huawei.com>
CC: stable@vger.kernel.org # v3.9+
We currently enable PCI bridges after scanning a bus and assigning
resources. This is often done in arch code.
This patch changes this so we don't enable a bridge until necessary, i.e.,
until we enable a PCI device behind the bridge. We do this in the generic
pci_enable_device() path, so this also removes the arch-specific code to
enable bridges.
[bhelgaas: changelog]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Since pcibios_release_device() called by pci_stop_and_remove_bus_device()
has removed the device from the EEH cache, we needn't do that again.
Cc: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that acpiphp_check_bridge() always enumerates devices behind the
bridge, there is no need to do that for each sub-bridge anymore like
it is done in the current ACPI-based PCI hotplug (ACPIPHP) code.
Given this we don't need check_sub_bridges() anymore, so drop that
function completely.
This also simplifies the ACPIPHP code a bit.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Do not acquire bridge_mutex around the addition of a slot to its
bridge's list of slots and arount the addition of a function to
its slot's list of functions, because that doesn't help anything
right now (those lists are walked without any locking anyway).
However, acquire bridge_mutex around the list walk in
acpiphp_remove_slots() and use list_for_each_entry() there,
because we terminate the walk as soon as we find the first matching
entry. This prevents that list walk from colliding with bridge
addition and removal.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Notice that functions enable_device() and disable_device() cannot
fail and their return values are ignored in the majority of places,
so redefine them as void and use the opportunity to change their
names to enable_slot() and disable_slot(), respectively, which much
better reflects what they do.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
There is no need for a temporary variable and all the tricks with
ternary operators in acpiphp_get_(latch)|(adapter)_status(). Change
those functions to be a bit more straightforward.
[rjw: Changelog]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Drop some unused symbols from acpiphp.h and redefine SLOT_ENABLED
(which is the only slot flag now) as 1.
[rjw: Redefinition of SLOT_ENABLED, changelog]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The current implementation of acpiphp_check_bridge() is pretty dumb:
- It enables a slot if it's not enabled and the slot status is
ACPI_STA_ALL.
- It disables a slot if it's enabled and the slot status is not
ACPI_STA_ALL.
This behavior is not sufficient to handle the Thunderbolt daisy
chaining case properly, however, because in that case the bus
behind the already enabled slot needs to be rescanned for new
devices.
For this reason, modify acpiphp_check_bridge() so that slots are
disabled and stopped if they are not in the ACPI_STA_ALL state.
For slots in the ACPI_STA_ALL state, devices behind them that don't
respond are trimmed using a new function, trim_stale_devices(),
introduced specifically for this purpose. That function walks
the given bus and checks each device on it. If the device doesn't
respond, it is assumed to be gone and is removed.
Once all of the stale devices directy behind the slot have been
removed, acpiphp_check_bridge() will start looking for new devices
that might have appeared on the given bus. It will do that even if
the slot is already enabled (SLOT_ENABLED is set for it).
In addition to that, make the bus check notification ignore
SLOT_ENABLED and go for enable_device() directly if bridge is NULL,
so that devices behind the slot are re-enumerated in that case too.
This change is based on earlier patches from Kirill A Shutemov
and Mika Westerberg.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Currently, enable_device() checks the return value of pci_scan_slot()
and returns immediately if that's 0 (meaning that no new functions
have been found in the slot). However, if one of the functions in
the slot is a bridge, some new devices may appear below it even if
the bridge itself is present continuously, so it generally is
necessary to do the rescan anyway just in case. [In particular,
that's necessary with the Thunderbolt daisy chaining in which case
new devices may be connected to the existing ones down the chain.]
The correctness of this change relies on the ability of
pcibios_resource_survey_bus() to detect if it has already been called
for the given bus and to skip it if so. Failure to do that will lead
to resource allocation conflicts.
[rjw: Changelog]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
With Thunderbolt you can daisy chain devices: connect new devices to
an already plugged one. In that case the "hotplug slot" is already
enabled, but we still want to look for new PCI devices behind it.
Reuse enable_device() to scan for new PCI devices on enabled slots
and push the SLOT_ENABLED check up into acpiphp_enable_slot().
[rjw: Rebased, modified the changelog]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI-based PCI hotplug (acpiphp) core code need not and really
should not execute _PS0 and _PS3 directly for devices it handles.
First of all, it is not necessary to put devices into D3 after
acpi_bus_trim() has walked through them, because
acpi_device_unregister() invoked by it puts each device into D3cold
before returning. Thus after disable_device() the slot should be
powered down already.
Second, calling _PS0 directly on ACPI device objects may not be
appropriate, because it may require power resources to be set up in
a specific way in advance and that must be taken care of by the ACPI
core. Thus modify acpiphp_bus_add() to power up the device using
the appropriate interface after it has run acpi_bus_scan() on its
handle.
After that, the functions executing _PS0 and _PS3, power_on_slot()
and power_off_slot(), are not necessary any more, so drop them
and update the code calling them accordingly. Also drop the
function flags related to device power states, since they aren't
useful any more too.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Modify handle_hotplug_event() to avoid queing up the execution of
handle_hotplug_event_work_fn() as a work item on kacpi_hotplug_wq
for non-hotplug events, such as ACPI_NOTIFY_DEVICE_WAKE. Move
the code printing diagnostic messages for those events into
handle_hotplug_event().
In addition to that, remove the bogus comment about how the core
should distinguish between hotplug and non-hotplug events and
queue them up on different workqueues. The core clearly cannot
know in advance what events will be interesting to the given
caller of acpi_install_notify_handler().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Both acpiphp_disable_slot() and acpiphp_eject_slot() are always
called together so instead of calling each separately we can
consolidate them into one function acpiphp_disable_and_eject_slot()
that does both (but it will return success on _EJ0 failures that
were ignored in the majority of call sites anyway).
[rjw: Rebased plus minor tweaks]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Two checks in check_hotplug_bridge() are redundant (they have been
done by the caller already), so drop them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The acpiphp_bus_trim() and acpiphp_bus_add() functions need not
return error codes that are never checked, so redefine them and
simplify them a bit.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
To avoid chasing more pointers than necessary in some situations,
move the bridge pointer from struct acpiphp_slot to struct
acpiphp_func (and call it 'parent') and add a bus pointer to
struct acpiphp_slot.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The handle field in struct acpiphp_bridge is only used by
acpiphp_enumerate_slots(), but in that function the local handle
variable can be used instead, so make that happen and drop handle
from struct acpiphp_bridge.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The ACPI handle stored in struct acpiphp_func is also stored in the
struct acpiphp_context object containing it and it is trivial to get
from a struct acpiphp_func pointer to the handle field of the outer
struct acpiphp_context.
Hence, the handle field of struct acpiphp_func is redundant, so drop
it and provide a helper function, func_to_handle(), allowing it
users to get the ACPI handle for the given struct acpiphp_func
pointer.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Since there has to be a struct acpiphp_func object for every struct
acpiphp_context created by register_slot(), the struct acpiphp_func
one can be embedded into the struct acpiphp_context one, which allows
some code simplifications to be made.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The only bridge flag used by the ACPI-based PCI hotplug (ACPIPHP)
code is BRIDGE_HAS_EJ0, but it is only used by the event handling
function hotplug_event() and if that flag is set, the corresponding
function flag FUNC_HAS_EJ0 is set as well, so that bridge flag is
redundant.
For this reason, drop BRIDGE_HAS_EJ0 and all code referring to it
and since it is the only bridge flag defined, drop the flags field
from struct acpiphp_bridge entirely.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
If the slot unique number is passed as an additional argument to
acpiphp_register_hotplug_slot(), the 'sun' field in struct
acpiphp_slot is only used by ibm_[s|g]et_attention_status(),
but then it's more efficient to store it in struct slot.
Thus move the 'sun' field from struct acpiphp_slot to struct slot
changing its data type to unsigned int in the process, and redefine
acpiphp_register_hotplug_slot() to take the slot number as separate
argument.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Rework register_slot() to create a struct acpiphp_func object for
every function it is called for and to create acpiphp slots for all
of them. Although acpiphp_register_hotplug_slot() is only called for
the slots whose functions are identified as "ejectable", so that user
space can manipulate them, the ACPIPHP notify handler,
handle_hotplug_event(), is now installed for all of the registered
functions (that aren't dock stations) and hotplug events may be
handled for all of them.
As a result, essentially, all PCI bridges represented by objects in
the ACPI namespace are now going to be "hotplug" bridges and that may
affect resources allocation in general, although it shouldn't lead to
problems.
This allows the code to be simplified substantially and addresses
the problem where bus check or device check notifications for some
PCI bridges or devices are not handled, because those devices are
not recognized as "ejectable" or there appear to be no "ejectable"
devices under those bridges.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
To make the code in register_slot() a bit easier to follow, change
the way the slot allocation part is organized. Drop one local
variable that's not used any more after that modification.
This code change should not lead to any changes in behavior.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Since the func pointer in struct acpiphp_context can always be used
instead of the func pointer in struct acpiphp_bridge, drop the
latter.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
There are separate handling event functions for hotplug bridges and
for hotplug functions, but they may be combined into one common
hotplug event handling function which simplifies the code slightly.
That also allows a theoretical bug to be dealt with which in
principle may occur if a hotplug bridge is on a dock station, because
in that case the bridge-specific notification should be used instead
of the function-specific one, but the dock station always uses the
latter.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Modify handle_hotplug_event() to pass the entire context object
(instead of its fields individually) to work functions started by it.
This change makes the subsequent consolidation of the event handling
work functions a bit more straightforward.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Using the hotplug context objects introduced previously rework the
ACPI-based PCI hotplug (ACPIPHP) core code to get to acpiphp_bridge
objects associated with hotplug bridges from those context objects
rather than from the global list of hotplug bridges.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
