PCI/ACPI: Use acpi_evaluate_dsm_typed()

The acpi_evaluate_dsm_typed() provides a way to check the type of the
object evaluated by _DSM call. Use it instead of open coded variant.

Link: https://lore.kernel.org/r/20231002135352.2603096-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>

PCI/sysfs: Protect driver's D3cold preference from user space

struct pci_dev contains two flags which govern whether the device may
suspend to D3cold:

* no_d3cold provides an opt-out for drivers (e.g. if a device is known
to not wake from D3cold)

* d3cold_allowed provides an opt-out for user space (default is true,
user space may set to false)

Since commit 9d26d3a8f1b0 ("PCI: Put PCIe ports into D3 during suspend"),
the user space setting overwrites the driver setting. Essentially user
space is trusted to know better than the driver whether D3cold is
working.

That feels unsafe and wrong. Assume that the change was introduced
inadvertently and do not overwrite no_d3cold when d3cold_allowed is
modified. Instead, consider d3cold_allowed in addition to no_d3cold
when choosing a suspend state for the device.

That way, user space may opt out of D3cold if the driver hasn't, but it
may no longer force an opt in if the driver has opted out.

Fixes: 9d26d3a8f1b0 ("PCI: Put PCIe ports into D3 during suspend")
Link: https://lore.kernel.org/r/b8a7f4af2b73f6b506ad8ddee59d747cbf834606.1695025365.git.lukas@wunner.de
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Cc: stable@vger.kernel.org # v4.8+

PCI/ACPI: Call _REG when transitioning D-states

ACPI r6.5, sec 6.5.4, describes how AML is unable to access an
OperationRegion unless _REG has been called to connect a handler:

The OS runs _REG control methods to inform AML code of a change in the
availability of an operation region. When an operation region handler is
unavailable, AML cannot access data fields in that region. (Operation
region writes will be ignored and reads will return indeterminate data.)

The PCI core does not call _REG at any time, leading to the undefined
behavior mentioned in the spec.

The spec explains that _REG should be executed to indicate whether a
given region can be accessed:

Once _REG has been executed for a particular operation region, indicating
that the operation region handler is ready, a control method can access
fields in the operation region. Conversely, control methods must not
access fields in operation regions when _REG method execution has not
indicated that the operation region handler is ready.

An example included in the spec demonstrates calling _REG when devices are
turned off: "when the host controller or bridge controller is turned off
or disabled, PCI Config Space Operation Regions for child devices are
no longer available. As such, ETH0’s _REG method will be run when it
is turned off and will again be run when PCI1 is turned off."

It is reported that ASMedia PCIe GPIO controllers fail functional tests
after the system has returning from suspend (S3 or s2idle). This is because
the BIOS checks whether the OSPM has called the _REG method to determine
whether it can interact with the OperationRegion assigned to the device as
part of the other AML called for the device.

To fix this issue, call acpi_evaluate_reg() when devices are transitioning
to D3cold or D0.

[bhelgaas: split pci_power_t checking to preliminary patch]
Link: https://uefi.org/specs/ACPI/6.5/06_Device_Configuration.html#reg-region
Link: https://lore.kernel.org/r/20230620140451.21007-1-mario.limonciello@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>

PCI/ACPI: Validate acpi_pci_set_power_state() parameter

Previously acpi_pci_set_power_state() assumed the requested power state was
valid (PCI_D0 ... PCI_D3cold). If a caller supplied something else, we
could index outside the state_conv[] array and pass junk to
acpi_device_set_power().

Validate the pci_power_t parameter and return -EINVAL if it's invalid.

Link: https://lore.kernel.org/r/20230621222857.GA122930@bhelgaas
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>

PCI/ACPI: Account for _S0W of the target bridge in acpi_pci_bridge_d3()

It is questionable to allow a PCI bridge to go into D3 if it has _S0W
returning D2 or a shallower power state, so modify acpi_pci_bridge_d3(() to
always take the return value of _S0W for the target bridge into account.
That is, make it return 'false' if _S0W returns D2 or a shallower power
state for the target bridge regardless of its ancestor Root Port
properties. Of course, this also causes 'false' to be returned if the Root
Port itself is the target and its _S0W returns D2 or a shallower power
state.

However, still allow bridges without _S0W that are power-manageable via
ACPI to enter D3 to retain the current code behavior in that case.

This fixes problems where a hotplug notification is missed because a bridge
is in D3. That means hot-added devices such as USB4 docks (and the devices
they contain) and Thunderbolt 3 devices may not work.

Link: https://lore.kernel.org/linux-pci/20221031223356.32570-1-mario.limonciello@amd.com/
Link: https://lore.kernel.org/r/12155458.O9o76ZdvQC@kreacher
Reported-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Use METHOD_NAME__UID instead of plain string

Replace the string "_UID" with the METHOD_NAME__UID macro so instances are
easier to find.

Link: https://lore.kernel.org/r/20221104032430.186424-1-zouyipeng@huawei.com
Signed-off-by: Yipeng Zou <zouyipeng@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Update link to PCI firmware specification

The previous link to the PCI firmware specification in the comments
for drivers/pci/pci-acpi.c no longer works. Update the comment
to a current link to this specification.

Link: https://lore.kernel.org/r/20220722174754.27921-1-mario.limonciello@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Allow D3 only if Root Port can signal and wake from D3

acpi_pci_bridge_d3(dev) returns "true" if "dev" is a hotplug bridge that
can handle hotplug events while in D3. Previously this meant either:

- "dev" has a _PS0 or _PR0 method (acpi_pci_power_manageable()), or

- The Root Port above "dev" has a _DSD with a "HotPlugSupportInD3"
property with value 1.

This did not consider _PRW, which tells us about wakeup GPEs (ACPI v6.4,
sec 7.3.13). Without a wakeup GPE, from an ACPI perspective the Root Port
has no way of generating wakeup signals, so hotplug events will be lost if
we use D3.

Similarly, it did not consider _S0W, which tells us the deepest D-state
from which a device can wake itself (sec 7.3.20). If _S0W tells us the
device cannot wake from D3, hotplug events will again be lost if we use D3.

Some platforms, e.g., AMD Yellow Carp, supply "HotPlugSupportInD3" without
_PRW or with an _S0W that says the Root Port cannot wake from D3. On those
platforms, we previously put bridges in D3hot, hotplug events were lost,
and hotplugged devices would not be recognized without manually rescanning.

Allow bridges to be put in D3 only if the Root Port can generate wakeup
GPEs (wakeup.flags.valid), it can wake from D3 (_S0W), AND it has the
"HotPlugSupportInD3" property.

Neither Windows 10 nor Windows 11 puts the bridge in D3 when the firmware
is configured this way, and this change aligns the handling of the
situation to be the same.

[bhelgaas: commit log, tidy "HotPlugSupportInD3" check and comment]
Link: https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/07_Power_and_Performance_Mgmt/device-power-management-objects.html?highlight=s0w#s0w-s0-device-wake-state
Link: https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-pcie-root-ports-supporting-hot-plug-in-d3
Link: https://lore.kernel.org/r/20220401034003.3166-1-mario.limonciello@amd.com
Fixes: 26ad34d510a87 ("PCI / ACPI: Whitelist D3 for more PCIe hotplug ports")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: ACPI: PM: Power up devices in D3cold before scanning them

The initial configuration of ACPI power resources on some systems
implies that some PCI devices on them are initially in D3cold.

In some cases, especially for PCIe Root Ports, this is a "logical"
D3cold, meaning that the configuration space of the device is
accessible, but some of its functionality may be missing, but it
very well may be real D3cold, in which case the device will not
be accessible at all. However, the PCI bus type driver will need
to access its configuration space in order to enumerate it.

To prevent possible device enumeration failures that may ensue as
a result of ACPI power resources being initially in the "off"
state, power up all children of the host bridge ACPI device object
that hold valid _ADR objects (which indicates that they will be
enumerated by the PCI bus type driver) and do that to all children
of the ACPI device objects corresponding to PCI bridges (including
PCIe ports).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

PCI/ACPI: Replace acpi_bus_get_device() with acpi_fetch_acpi_dev()

Replace acpi_bus_get_device() that is going to be dropped with
acpi_fetch_acpi_dev().

No intentional functional impact.

Link: https://lore.kernel.org/r/11930209.O9o76ZdvQC@kreacher
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

PCI: PM: Make pci_choose_state() call pci_target_state()

The pci_choose_state() and pci_target_state() implementations are
somewhat divergent without a good reason, because they are used
for similar purposes.

Change the pci_choose_state() implementation to use pci_target_state()
internally except for transitions to the working state of the system
in which case it is expected to return D0.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>

PCI: PM: Simplify acpi_pci_power_manageable()

Make acpi_pci_power_manageable() more straightforward.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>

PCI: ACPI: PM: Do not use pci_platform_pm_ops for ACPI

Using struct pci_platform_pm_ops for ACPI adds unnecessary
indirection to the interactions between the PCI core and ACPI PM,
which is also subject to retpolines.

Moreover, it is not particularly clear from the current code that,
as far as PCI PM is concerned, "platform" really means just ACPI
except for the special casess when Intel MID PCI PM is used or when
ACPI support is disabled (through the kernel config or command line,
or because there are no usable ACPI tables on the system).

To address the above, rework the PCI PM code to invoke ACPI PM
functions directly as needed and drop the acpi_pci_platform_pm
object that is not necessary any more.

Accordingly, update some of the ACPI PM functions in question to do
extra checks in case the ACPI support is disabled (which previously
was taken care of by avoiding to set the pci_platform_ops pointer
in those cases).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>

PCI: ACPI: Drop acpi_pci_bus

The acpi_pci_bus structure was used primarily for running
acpi_pci_find_companion() during PCI device objects registration,
but after commit 375553a93201 ("PCI: Setup ACPI fwnode early and at
the same time with OF") that function is called by pci_setup_device()
via pci_set_acpi_fwnode(), which happens before calling
pci_device_add() on the new PCI device object, so its ACPI companion
has been set already when acpi_device_notify() runs and it will never
call ->find_companion() from acpi_pci_bus.

For this reason, modify acpi_device_notify() and
acpi_device_notify_remove() to call pci_acpi_setup() and
pci_acpi_cleanup(), respectively, directly on PCI device objects
and drop acpi_pci_bus altogether.

While at it, notice that pci_acpi_setup() and pci_acpi_cleanup()
can obtain the ACPI companion pointer, which is guaranteed to not
be NULL, from their callers and modify them to work that way so
as to reduce the number of redundant checks somewhat.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Ferry Toth <fntoth@gmail.com>

PCI: ACPI: Check parent pointer in acpi_pci_find_companion()

If acpi_pci_find_companion() is called for a device whose parent
pointer is NULL, it will crash when attempting to get the ACPI
companion of the parent due to a NULL pointer dereference in
the ACPI_COMPANION() macro.

This was not a problem before commit 375553a93201 ("PCI: Setup ACPI
fwnode early and at the same time with OF") that made pci_setup_device()
call pci_set_acpi_fwnode() and so it allowed devices with NULL parent
pointers to be passed to acpi_pci_find_companion() which is the case
in pci_iov_add_virtfn(), for instance.

Fix this issue by making acpi_pci_find_companion() check the device's
parent pointer upfront and bail out if it is NULL.

While pci_iov_add_virtfn() can be changed to set the device's parent
pointer before calling pci_setup_device() for it, checking pointers
against NULL before dereferencing them is prudent anyway and looking
for ACPI companions of virtual functions isn't really useful.

Fixes: 375553a93201 ("PCI: Setup ACPI fwnode early and at the same time with OF")
Link: https://lore.kernel.org/linux-acpi/8e4bbd5c59de31db71f718556654c0aa077df03d.camel@linux.ibm.com/
Reported-by: Niklas Schnelle <schnelle@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Don't reset a fwnode set by OF

Commit 375553a93201 ("PCI: Setup ACPI fwnode early and at the same time
with OF") added a call to pci_set_acpi_fwnode() in pci_setup_device(),
which unconditionally clears any fwnode previously set by
pci_set_of_node().

pci_set_acpi_fwnode() looks for ACPI_COMPANION(), which only returns the
existing fwnode if it was set by ACPI_COMPANION_SET(). If it was set by
OF instead, ACPI_COMPANION() returns NULL and pci_set_acpi_fwnode()
accidentally clears the fwnode. To fix this, look for any fwnode instead
of just ACPI companions.

Fixes a virtio-iommu boot regression in v5.15-rc1.

Fixes: 375553a93201 ("PCI: Setup ACPI fwnode early and at the same time with OF")
Link: https://lore.kernel.org/r/20210913172358.1775381-1-jean-philippe@linaro.org
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: VMD: ACPI: Make ACPI companion lookup work for VMD bus

On some systems, in order to get to the deepest low-power state of
the platform (which may be necessary to save significant enough
amounts of energy while suspended to idle. for example), devices on
the PCI bus exposed by the VMD driver need to be power-managed via
ACPI. However, the layout of the ACPI namespace below the VMD
controller device object does not reflect the layout of the PCI bus
under the VMD host bridge, so in order to identify the ACPI companion
objects for the devices on that bus, it is necessary to use a special
_ADR encoding on the ACPI side. In other words, acpi_pci_find_companion()
does not work for these devices, so it needs to be amended with a
special lookup logic specific to the VMD bus.

Address this issue by allowing the VMD driver to temporarily install
an ACPI companion lookup hook containing the code matching the devices
on the VMD PCI bus with the corresponding objects in the ACPI
namespace.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Jon Derrick <jonathan.derrick@intel.com>

PCI: Change the type of probe argument in reset functions

Change the type of probe argument in functions which implement reset
methods from int to bool to make the context and intent clear.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-10-ameynarkhede03@gmail.com
Signed-off-by: Amey Narkhede <ameynarkhede03@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Add support for ACPI _RST reset method

_RST is a standard ACPI method that performs a function level reset of a
device (ACPI v6.3, sec 7.3.25).

Add pci_dev_acpi_reset() to probe for _RST method and execute if present.
The default priority of this reset is set to below device-specific and
above hardware resets.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20210817180500.1253-9-ameynarkhede03@gmail.com
Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Sinan Kaya <okaya@kernel.org>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>

PCI: Setup ACPI fwnode early and at the same time with OF

Previously, the ACPI_COMPANION() of a pci_dev was usually set by
acpi_bind_one() in this path:

pci_device_add
pci_configure_device
pci_init_capabilities
device_add
device_platform_notify
acpi_platform_notify
acpi_device_notify # KOBJ_ADD
acpi_bind_one
ACPI_COMPANION_SET

However, things like pci_configure_device() and pci_init_capabilities()
that run before device_add() need the ACPI_COMPANION, e.g.,
acpi_pci_bridge_d3() uses a _DSD method to learn about D3 support. These
places had special-case code to manually look up the ACPI_COMPANION.

Set the ACPI_COMPANION earlier, in pci_setup_device(), so it will be
available while configuring the device. This covers both paths to creating
pci_dev objects:

pci_scan_single_device # for normal non-SR-IOV devices
pci_scan_device
pci_setup_device
pci_set_acpi_fwnode
pci_device_add

pci_iov_add_virtfn # for SR-IOV virtual functions
pci_setup_device
pci_set_acpi_fwnode

Also move the OF fwnode setup to the same spot.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20210817180500.1253-8-ameynarkhede03@gmail.com
Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>

PCI: Use acpi_pci_power_manageable()

Use acpi_pci_power_manageable() instead of duplicating the logic in
acpi_pci_bridge_d3(). No functional change intended.

[bhelgaas: split out from
https://lore.kernel.org/r/20210817180500.1253-8-ameynarkhede03@gmail.com]
Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Add pci_set_acpi_fwnode() to set ACPI_COMPANION

Move the existing logic from acpi_pci_bridge_d3() to a separate function
pci_set_acpi_fwnode() to set the ACPI fwnode. No functional change
intended.

Link: https://lore.kernel.org/r/20210817180500.1253-7-ameynarkhede03@gmail.com
Signed-off-by: Shanker Donthineni <sdonthineni@nvidia.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>

PCI/ACPI: Fix acpi_pci_set_power_state() debug message

If PCI_D3cold is passed to acpi_pci_set_power_state() as the second
argument and there is no ACPI D3cold support for the given device, the
debug message will state that the device power state has been changed to
D3cold, while in fact it will be D3hot, because acpi_device_set_power()
falls back to D3hot automatically if D3cold is not supported without
returning an error.

To address this issue, modify the debug message to print the current power
state of the target PCI device's ACPI companion instead of printing the
target power state, which may not reflect the real final power state of the
device.

Link: https://lore.kernel.org/r/4319486.LvFx2qVVIh@kreacher
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Wilczyński <kw@linux.com>

PCI/ACPI: Fix companion lookup for device 0 on the root bus

In some cases acpi_pci_find_companion() returns an incorrect device object
as the ACPI companion for device 0 on the root bus (bus 0).

On the affected systems that device is the PCI interface to the host bridge
and the "ACPI companion" returned for it corresponds to a non-PCI device
located in the SoC (e.g. a sensor on an I2C bus). As a result of this, the
ACPI device object "attached" to PCI device 00:00.0 cannot be used for
enumerating the device that is really represented by it which (of course)
is problematic.

Address that issue by preventing acpi_pci_find_companion() from returning a
device object with a valid _HID (which by the spec should not be present
uder ACPI device objects corresponding to PCI devices) for PCI device
00:00.0.

[bhelgaas: use pci_is_root_bus()]
Link: https://lore.kernel.org/linux-acpi/1409ba0c-1580-dc09-e6fe-a0c9bcda6462@gmail.com/
Link: https://lore.kernel.org/r/4673285.9aE2nYKHPr@kreacher
Reported-by: Daniel Scally <djrscally@gmail.com>
Tested-by: Daniel Scally <djrscally@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Daniel Scally <djrscally@gmail.com>

PM: ACPI: PCI: Drop acpi_pm_set_bridge_wakeup()

The idea behind acpi_pm_set_bridge_wakeup() was to allow bridges to
be reference counted for wakeup enabling, because they may be enabled
to signal wakeup on behalf of their subordinate devices and that
may happen for multiple times in a row, whereas for the other devices
it only makes sense to enable wakeup signaling once.

However, this becomes problematic if the bridge itself is suspended,
because it is treated as a "regular" device in that case and the
reference counting doesn't work.

For instance, suppose that there are two devices below a bridge and
they both can signal wakeup. Every time one of them is suspended,
wakeup signaling is enabled for the bridge, so when they both have
been suspended, the bridge's wakeup reference counter value is 2.

Say that the bridge is suspended subsequently and acpi_pci_wakeup()
is called for it. Because the bridge can signal wakeup, that
function will invoke acpi_pm_set_device_wakeup() to configure it
and __acpi_pm_set_device_wakeup() will be called with the last
argument equal to 1. This causes __acpi_device_wakeup_enable()
invoked by it to omit the reference counting, because the reference
counter of the target device (the bridge) is 2 at that time.

Now say that the bridge resumes and one of the device below it
resumes too, so the bridge's reference counter becomes 0 and
wakeup signaling is disabled for it, but there is still the other
suspended device which may need the bridge to signal wakeup on its
behalf and that is not going to work.

To address this scenario, use wakeup enable reference counting for
all devices, not just for bridges, so drop the last argument from
__acpi_device_wakeup_enable() and __acpi_pm_set_device_wakeup(),
which causes acpi_pm_set_device_wakeup() and
acpi_pm_set_bridge_wakeup() to become identical, so drop the latter
and use the former instead of it everywhere.

Fixes: 1ba51a7c1496 ("ACPI / PCI / PM: Rework acpi_pci_propagate_wakeup()")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+

PCI/ACPI: Whitelist hotplug ports for D3 if power managed by ACPI

Recent laptops with dual AMD GPUs fail to suspend the discrete GPU, thus
causing lockups on system sleep and high power consumption at runtime.
The discrete GPU would normally be suspended to D3cold by turning off
ACPI _PR3 Power Resources of the Root Port above the GPU.

However on affected systems, the Root Port is hotplug-capable and
pci_bridge_d3_possible() only allows hotplug ports to go to D3 if they
belong to a Thunderbolt device or if the Root Port possesses a
"HotPlugSupportInD3" ACPI property. Neither is the case on affected
laptops. The reason for whitelisting only specific, known to work
hotplug ports for D3 is that there have been reports of SkyLake Xeon-SP
systems raising Hardware Error NMIs upon suspending their hotplug ports:
https://lore.kernel.org/linux-pci/20170503180426.GA4058@otc-nc-03/

But if a hotplug port is power manageable by ACPI (as can be detected
through presence of Power Resources and corresponding _PS0 and _PS3
methods) then it ought to be safe to suspend it to D3. To this end,
amend acpi_pci_bridge_d3() to whitelist such ports for D3.

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1222
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1252
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1304
Reported-and-tested-by: Arthur Borsboom <arthurborsboom@gmail.com>
Reported-and-tested-by: matoro <matoro@airmail.cc>
Reported-by: Aaron Zakhrov <aaron.zakhrov@gmail.com>
Reported-by: Michal Rostecki <mrostecki@suse.com>
Reported-by: Shai Coleman <git@shaicoleman.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI/PM: Rename pci_dev.d3_delay to d3hot_delay

PCI devices support two variants of the D3 power state: D3hot (main power
present) D3cold (main power removed). Previously struct pci_dev contained:

unsigned int d3_delay; /* D3->D0 transition time in ms */
unsigned int d3cold_delay; /* D3cold->D0 transition time in ms */

"d3_delay" refers specifically to the D3hot state. Rename it to
"d3hot_delay" to avoid ambiguity and align with the ACPI "_DSM for
Specifying Device Readiness Durations" in the PCI Firmware spec r3.2,
sec 4.6.9.

There is no change to the functionality.

Link: https://lore.kernel.org/r/20200730210848.1578826-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Treat "external-facing" devices themselves as internal

"External-facing" devices are internal devices that expose PCIe hierarchies
such as Thunderbolt outside the platform [1]. Previously these internal
devices were marked as "untrusted" the same as devices downstream from
them.

Use the ACPI or DT information to identify external-facing devices, but
only mark the devices *downstream* from them as "untrusted" [2]. The
external-facing device itself is no longer marked as untrusted.

[1] https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports
[2] https://lore.kernel.org/linux-pci/20200610230906.GA1528594@bjorn-Precision-5520/
Link: https://lore.kernel.org/r/20200707224604.3737893-3-rajatja@google.com
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through # [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: Rename _DSM constants to align with spec

Rename PCI-related _DSM constants to align them with the PCI Firmware Spec,
r3.2, sec 4.6. No functional change intended.

Link: https://lore.kernel.org/r/20200526213905.2479381-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Unify pcie_find_root_port() and pci_find_pcie_root_port()

Previously we used pcie_find_root_port() to find a Root Port from a PCIe
device and pci_find_pcie_root_port() to find a Root Port from a
Conventional PCI device.

Unify the two functions and use pcie_find_root_port() to find a Root Port
from either a Conventional PCI device or a PCIe device. Then there is no
need to distinguish the type of the device.

Link: https://lore.kernel.org/r/1589019568-5216-1-git-send-email-yangyicong@hisilicon.com
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # thunderbolt

PCI/DPC: Add Error Disconnect Recover (EDR) support

Error Disconnect Recover (EDR) is a feature that allows ACPI firmware to
notify OSPM that a device has been disconnected due to an error condition
(ACPI v6.3, sec 5.6.6). OSPM advertises its support for EDR on PCI devices
via _OSC (see [1], sec 4.5.1, table 4-4). The OSPM EDR notify handler
should invalidate software state associated with disconnected devices and
may attempt to recover them. OSPM communicates the status of recovery to
the firmware via _OST (sec 6.3.5.2).

For PCIe, firmware may use Downstream Port Containment (DPC) to support
EDR. Per [1], sec 4.5.1, table 4-6, even if firmware has retained control
of DPC, OSPM may read/write DPC control and status registers during the EDR
notification processing window, i.e., from the time it receives an EDR
notification until it clears the DPC Trigger Status.

Note that per [1], sec 4.5.1 and 4.5.2.4,

1. If the OS supports EDR, it should advertise that to firmware by
setting OSC_PCI_EDR_SUPPORT in _OSC Support.

2. If the OS sets OSC_PCI_EXPRESS_DPC_CONTROL in _OSC Control to request
control of the DPC capability, it must also set OSC_PCI_EDR_SUPPORT in
_OSC Support.

Add an EDR notify handler to attempt recovery.

[1] Downstream Port Containment Related Enhancements ECN, Jan 28, 2019,
affecting PCI Firmware Specification, Rev. 3.2
https://members.pcisig.com/wg/PCI-SIG/document/12888

[bhelgaas: squash add/enable patches into one]
Link: https://lore.kernel.org/r/90f91fe6d25c13f9d2255d2ce97ca15be307e1bb.1585000084.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>

PCI/ACPI: Move pcie_to_hpx3_type[] from stack to static data

Move pcie_to_hpx3_type[] from the stack to static data. This reduces stack
usage and also makes the object code slightly smaller.

Link: https://lore.kernel.org/r/20200210085256.319424-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Remove unnecessary struct hotplug_program_ops

Move the ACPI-specific structs hpx_type0, hpx_type1, hpx_type2 and
hpx_type3 to drivers/pci/pci-acpi.c as they are not used anywhere else.
Then remove the struct hotplug_program_ops that has been shared between
drivers/pci/probe.c and drivers/pci/pci-acpi.c from drivers/pci/pci.h as it
is no longer needed.

The struct hotplug_program_ops was added by 87fcf12e846a ("PCI/ACPI: Remove
the need for 'struct hotplug_params'") and replaced previously used struct
hotplug_params enabling the support for the _HPX Type 3 Setting Record that
was added by f873c51a155a ("PCI/ACPI: Implement _HPX Type 3 Setting
Record").

The new struct allowed for the static functions such program_hpx_type0(),
program_hpx_type1(), etc., from the drivers/pci/probe.c to be called from
the function pci_acpi_program_hp_params() in the drivers/pci/pci-acpi.c.

Previously a programming of _HPX Type 0 was as follows:

drivers/pci/probe.c:

program_hpx_type0()
...
pci_configure_device()
hp_ops = {
.program_type0 = program_hpx_type0,
...
}
pci_acpi_program_hp_params(&hp_ops)

drivers/pci/pci-acpi.c:

pci_acpi_program_hp_params(&hp_ops)
acpi_run_hpx(hp_ops)
decode_type0_hpx_record()
hp_ops->program_type0 # program_hpx_type0() called via hp_ops

After the ACPI-specific functions, structs, enums, etc., have been moved to
drivers/pci/pci-acpi.c there is no need for the hotplug_program_ops as all
of the _HPX Type 0, 1, 2 and 3 are directly accessible.

Link: https://lore.kernel.org/r/20190827094951.10613-4-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Move _HPP & _HPX functions to pci-acpi.c

Move program_hpx_type0(), program_hpx_type1(), etc., and enums
hpx_type3_dev_type, hpx_type3_fn_type and hpx_type3_cfg_loc to
drivers/pci/pci-acpi.c as these functions and enums are ACPI-specific.

Move structs hpx_type0, hpx_type1, hpx_type2 and hpx_type3 to
drivers/pci/pci.h as these are shared between drivers/pci/pci-acpi.c and
drivers/pci/probe.c.

Link: https://lore.kernel.org/r/20190827094951.10613-3-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Rename _HPX structs from hpp_* to hpx_*

The names of the hpp_type0, hpp_type1 and hpp_type2 structs suggest that
they're related to _HPP, when in fact they're related to _HPX.

The struct hpp_type0 denotes an _HPX Type 0 setting record that supersedes
the _HPP setting record, and it has been used interchangeably for _HPP as
per the ACPI specification (see version 6.3, section 6.2.9.1) which states
that it should be applied to PCI, PCI-X and PCI Express devices, with
settings being ignored if they are not applicable.

Rename them to hpx_type0, hpx_type1 and hpx_type2 to reflect their relation
to _HPX rather than _HPP.

Link: https://lore.kernel.org/r/20190827094951.10613-2-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Move ASPM declarations to linux/pci.h

Move ASPM definitions and function prototypes from include/linux/pci-aspm.h
to include/linux/pci.h so users only need to include <linux/pci.h>:

PCIE_LINK_STATE_L0S
PCIE_LINK_STATE_L1
PCIE_LINK_STATE_CLKPM
pci_disable_link_state()
pci_disable_link_state_locked()
pcie_no_aspm()

No functional changes intended.

Link: https://lore.kernel.org/r/20190827095620.11213-1-kw@linux.com
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: PM/ACPI: Refresh all stale power state data in pci_pm_complete()

In pci_pm_complete() there are checks to decide whether or not to
resume devices that were left in runtime-suspend during the preceding
system-wide transition into a sleep state. They involve checking the
current power state of the device and comparing it with the power
state of it set before the preceding system-wide transition, but the
platform component of the device's power state is not handled
correctly in there.

Namely, on platforms with ACPI, the device power state information
needs to be updated with care, so that the reference counters of
power resources used by the device (if any) are set to ensure that
the refreshed power state of it will be maintained going forward.

To that end, introduce a new ->refresh_state() platform PM callback
for PCI devices, for asking the platform to refresh the device power
state data and ensure that the corresponding power state will be
maintained going forward, make it invoke acpi_device_update_power()
(for devices with ACPI PM) on platforms with ACPI and make
pci_pm_complete() use it, through a new pci_refresh_power_state()
wrapper function.

Fixes: a0d2a959d3da (PCI: Avoid unnecessary resume after direct-complete)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

PCI / ACPI: Add _PR0 dependent devices

If otherwise unrelated PCI devices share ACPI power resources turning
them on causes the devices to enter D0uninitialized power state which may
cause problems.

For example in Intel Ice Lake two root ports (RP0 and RP1), Thunderbolt
controller (NHI) and xHCI controller all share power resources as can be
ween in the topology below where power resources are marked with []:

Host bridge
|
+- RP0 ---\
+- RP1 ---|--+--> [TBT]
+- NHI --/ |
| |
| v
+- xHCI --> [D3C]

In a situation where all devices sharing the power resources are in
D3cold (the power resources are turned off) and for example the
Thunderbolt controller is runtime resumed resulting that the power
resources are turned on. This means that the other devices sharing them
(RP0, RP1 and xHCI) are transitioned into D0uninitialized state. If they
were configured to trigger wake (PME) on a certain event that
configuration gets lost after reset so we would need to re-initialize
them to get the wakeup working as expected again. To do so we would need
to runtime resume all of them to make sure their registers get restored
properly before we can runtime suspend them again.

Since we just added concept of "_PR0 dependent device" we can solve this
by calling the relevant add/remove functions when the PCI device is bind
to its ACPI representation. If it has power resources the PCI device
will be added as dependent device to them and runtime resumed whenever
they are physically turned on. This should make sure PCI core can
reconfigure wakes after the device is transitioned into D0uninitialized.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI / ACPI: Use cached ACPI device state to get PCI device power state

The ACPI power state returned by acpi_device_get_power() may depend on
the configuration of ACPI power resources in the system which may change
any time after acpi_device_get_power() has returned, unless the
reference counters of the ACPI power resources in question are set to
prevent that from happening. Thus it is invalid to use acpi_device_get_power()
in acpi_pci_get_power_state() the way it is done now and the value of
the ->power.state field in the corresponding struct acpi_device objects
(which reflects the ACPI power resources reference counting, among other
things) should be used instead.

As an example where this becomes an issue is Intel Ice Lake where the
Thunderbolt controller (NHI), two PCIe root ports (RP0 and RP1) and xHCI
all share the same power resources. The following picture with power
resources marked with [] shows the topology:

Host bridge
|
+- RP0 ---\
+- RP1 ---|--+--> [TBT]
+- NHI --/ |
| |
| v
+- xHCI --> [D3C]

Here TBT and D3C are the shared ACPI power resources. ACPI _PR3() method
of the devices in question returns either TBT or D3C or both.

Say we runtime suspend first the root ports RP0 and RP1, then NHI. Now
since the TBT power resource is still on when the root ports are runtime
suspended their dev->current_state is set to D3hot. When NHI is runtime
suspended TBT is finally turned off but state of the root ports remain
to be D3hot. Now when the xHCI is runtime suspended D3C gets also turned
off. PCI core thus has power states of these devices cached in their
dev->current_state as follows:

RP0 -> D3hot
RP1 -> D3hot
NHI -> D3cold
xHCI -> D3cold

If the user now runs lspci for instance, the result is all 1's like in
the below output (00:07.0 is the first root port, RP0):

00:07.0 PCI bridge: Intel Corporation Device 8a1d (rev ff) (prog-if ff)
!!! Unknown header type 7f
Kernel driver in use: pcieport

In short the hardware state is not in sync with the software state
anymore. The exact same thing happens with the PME polling thread which
ends up bringing the root ports back into D0 after they are runtime
suspended.

For this reason, modify acpi_pci_get_power_state() so that it uses the
ACPI device power state that was cached by the ACPI core. This makes the
PCI device power state match the ACPI device power state regardless of
state of the shared power resources which may still be on at this point.

Link: https://lore.kernel.org/r/20190618161858.77834-2-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI/PCI: PM: Add missing wakeup.flags.valid checks

Both acpi_pci_need_resume() and acpi_dev_needs_resume() check if the
current ACPI wakeup configuration of the device matches what is
expected as far as system wakeup from sleep states is concerned, as
reflected by the device_may_wakeup() return value for the device.

However, they only should do that if wakeup.flags.valid is set for
the device's ACPI companion, because otherwise the wakeup.prepare_count
value for it is meaningless.

Add the missing wakeup.flags.valid checks to these functions.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

PCI: Replace printk(KERN_INFO) with pr_info(), etc

Replace printk() with pr_*() to be more consistent with other logging and
avoid checkpatch warnings.

Link: https://lore.kernel.org/lkml/1555733026-19609-1-git-send-email-mohankumar718@gmail.com
Link: https://lore.kernel.org/lkml/1555733130-19804-1-git-send-email-mohankumar718@gmail.com
Signed-off-by: Mohan Kumar <mohankumar718@gmail.com>
[bhelgaas: squash in similar changes from second patch in series]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Implement _HPX Type 3 Setting Record

The _HPX Type 3 Setting Record is intended to be more generic and allow
configuration of settings not possible with Type 2 records. For example,
firmware could ensure that the completion timeout value is set accordingly
throughout the PCI tree.

Implement support for _HPX Type 3 Setting Records, which were added in the
ACPI 6.3 spec.

Link: https://lore.kernel.org/lkml/20190208162414.3996-4-mr.nuke.me@gmail.com
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Remove the need for 'struct hotplug_params'

We used to first parse all the _HPP and _HPX tables before using the
information to program registers of PCIe devices. Up through HPX Type 2,
there was only one structure of each type, so we could cheat and store it
on the stack.

With HPX Type 3 we get an arbitrary number of entries, so the above model
doesn't scale that well. Instead of parsing all tables at once, parse and
program each entry separately. For _HPP and _HPX Types 0 through 2, this
is functionally equivalent. The change enables the upcoming _HPX Type 3 to
integrate more easily.

Link: https://lore.kernel.org/lkml/20190208162414.3996-3-mr.nuke.me@gmail.com
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
[bhelgaas: fix build errors]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: Do not export pci_get_hp_params()

pci_get_hp_params() is only used within drivers/pci, and there is no reason
to make it available outside of the PCI core, so stop exporting it.

Link: https://lore.kernel.org/lkml/20190208162414.3996-2-mr.nuke.me@gmail.com
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / ACPI: Identify untrusted PCI devices

A malicious PCI device may use DMA to attack the system. An external
Thunderbolt port is a convenient point to attach such a device. The OS
may use IOMMU to defend against DMA attacks.

Some BIOSes mark these externally facing root ports with this
ACPI _DSD [1]:

Name (_DSD, Package () {
ToUUID ("efcc06cc-73ac-4bc3-bff0-76143807c389"),
Package () {
Package () {"ExternalFacingPort", 1},
Package () {"UID", 0 }
}
})

If we find such a root port, mark it and all its children as untrusted.
The rest of the OS may use this information to enable DMA protection
against malicious devices. For instance the device may be put behind an
IOMMU to keep it from accessing memory outside of what the driver has
allocated for it.

While at it, add a comment on top of prp_guids array explaining the
possible caveat resulting when these GUIDs are treated equivalent.

[1] https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

Revert "ACPI/PCI: Pay attention to device-specific _PXM node values"

This reverts commit bad7dcd94f3956bcfc0a69ef71fdf0fcca3de4a8.

bad7dcd94f39 ("ACPI/PCI: Pay attention to device-specific _PXM node
values") caused boot failures (no console output at all) for Martin [1]
and Ingo [2] on AMD ThreadRipper systems.

Revert the commit until we figure out how to safely use these
device-specific _PXM values.

[1] https://lore.kernel.org/linux-pci/20180912152140.3676-2-Jonathan.Cameron@huawei.com
[2] https://lore.kernel.org/linux-pci/20181113071712.GA2353@gmail.com
Fixes: bad7dcd94f39 ("ACPI/PCI: Pay attention to device-specific _PXM node values")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / ACPI: Mark expected switch fall-through

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 1472052 ("Missing break in switch")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / ACPI: Whitelist D3 for more PCIe hotplug ports

In order to have better power management for Thunderbolt PCIe chains,
Windows enables power management for native PCIe hotplug ports if there is
the following ACPI _DSD attached to the root port:

Name (_DSD, Package () {
ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"),
Package () {
Package () {"HotPlugSupportInD3", 1}
}
})

This is also documented in:

https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-pcie-root-ports-supporting-hot-plug-in-d3

Do the same in Linux by introducing new firmware PM callback
(->bridge_d3()) and then implement it for ACPI based systems so that the
above property is checked.

There is one catch, though. The initial pci_dev->bridge_d3 is set before
the root port has ACPI companion bound (the device is not added to the PCI
bus either) so we need to look up the ACPI companion manually in that case
in acpi_pci_bridge_d3().

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI / ACPI: Enable wake automatically for power managed bridges

We enable power management automatically for bridges where
pci_bridge_d3_possible() returns true. However, these bridges may have
ACPI methods such as _DSW that need to be called before D3 entry. For
example in Lenovo Thinkpad X1 Carbon 6th _DSW method is used to prepare
D3cold for the PCIe root port hosting Thunderbolt chain. Because wake is
not enabled _DSW method is never called and the port does not enter
D3cold properly consuming more power than necessary.

Users can work this around by writing "enabled" to "wakeup" sysfs file
under the device in question but that is not something an ordinary user
is expected to do.

Since we already automatically enable power management for PCIe ports
with ->bridge_d3 set extend that to enable wake for them as well,
assuming the port has any ACPI wakeup related objects implemented in the
namespace (adev->wakeup.flags.valid is true). This ensures the necessary
ACPI methods get called at appropriate times and allows the root port in
Thinkpad X1 Carbon 6th to go into D3cold.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI/PCI: Pay attention to device-specific _PXM node values

The ACPI specification allows you to provide _PXM entries for devices based
on their location on a particular bus. Let us use that if it is provided
rather than just assuming it makes sense to put the device into the
proximity domain of the root.

An example DSDT entry that will supply this is:

Device (PCI2)
{
Name (_HID, "PNP0A08") // PCI Express Root Bridge
Name (_CID, "PNP0A03") // Compatible PCI Root Bridge
Name(_SEG, 2) // Segment of this Root complex
Name(_BBN, 0xF8) // Base Bus Number
Name(_CCA, 1)
Method (_PXM, 0, NotSerialized) {
Return(0x00)
}

...
Device (BRI0) {
Name (_HID, "19E51610")
Name (_ADR, 0)
Name (_BBN, 0xF9)
Device (CAR0) {
Name (_HID, "97109912")
Name (_ADR, 0)
Method (_PXM, 0, NotSerialized) {
Return(0x02)
}
}
}
}

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / ACPI / PM: Resume all bridges on suspend-to-RAM

Commit 26112ddc254c (PCI / ACPI / PM: Resume bridges w/o drivers on
suspend-to-RAM) attempted to fix a functional regression resulting
from commit c62ec4610c40 (PM / core: Fix direct_complete handling
for devices with no callbacks) by resuming PCI bridges without
drivers (that is, "parallel PCI" ones) during system-wide suspend if
the target system state is not ACPI S0 (working state).

That turns out insufficient, however, as it is reported that, at
least in one case, the platform firmware gets confused if a PCIe
root port is suspended before entering the ACPI S3 sleep state.
That issue was exposed by commit 77b3729ca03 (PCI / PM: Use
SMART_SUSPEND and LEAVE_SUSPENDED flags for PCIe ports) that allowed
PCIe ports to stay in runtime suspend during system-wide suspend
(which is OK for suspend-to-idle, but turns out to be problematic
otherwise).

For this reason, drop the driver check from acpi_pci_need_resume()
and resume all bridges (including PCIe ports with drivers) during
system-wide suspend if the target system state is not ACPI S0.

[If the target system state is ACPI S0, it means suspend-to-idle
and the platform firmware is not going to be invoked to actually
suspend the system, so there is no need to resume the bridges in
that case.]

Fixes: 77b3729ca03 (PCI / PM: Use SMART_SUSPEND and LEAVE_SUSPENDED flags for PCIe ports)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=200675
Reported-by: teika kazura <teika@gmx.com>
Tested-by: teika kazura <teika@gmx.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: 4.16+ <stable@vger.kernel.org> # 4.16+: 26112ddc254c (PCI / ACPI / PM: Resume bridges ...)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI / ACPI / PM: Resume bridges w/o drivers on suspend-to-RAM

It is reported that commit c62ec4610c40 (PM / core: Fix direct_complete
handling for devices with no callbacks) introduced a system suspend
regression on Samsung 305V4A by allowing a PCI bridge (not a PCIe
port) to stay in D3 over suspend-to-RAM, which is a side effect of
setting power.direct_complete for the children of that bridge that
have no PM callbacks.

On the majority of systems PCI bridges are not allowed to be
runtime-suspended (the power/control sysfs attribute is set to "on"
for them by default), but user space can change that setting and if
it does so and a given bridge has no children with PM callbacks, the
direct_complete optimization will be applied to it and it will stay
in suspend over system suspend. Apparently, that confuses the
platform firmware on the affected machine and that may very well
happen elsewhere, so avoid the direct_complete optimization for
PCI bridges with no drivers (if there is a driver, it should take
care of the PM handling) on suspend-to-RAM altogether (that should
not matter for suspend-to-idle as platform firmware is not involved
in it).

Fixes: c62ec4610c40 (PM / core: Fix direct_complete handling for devices with no callbacks)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=199941
Reported-by: n0000b.n000b@gmail.com
Tested-by: n0000b.n000b@gmail.com
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: 4.15+ <stable@vger.kernel.org> # 4.15+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: shpchp: Separate existence of SHPC and permission to use it

The shpchp driver registers for all PCI bridge devices. Its probe method
should fail if either (1) the bridge doesn't have an SHPC or (2) the OS
isn't allowed to use it (the platform firmware may be operating the SHPC
itself).

Separate these two tests into:

- A new shpc_capable() that looks for the SHPC hardware and is applicable
on all systems (ACPI and non-ACPI), and

- A simplified acpi_get_hp_hw_control_from_firmware() that we call only
when we already know an SHPC exists and there may be ACPI methods to
either request permission to use it (_OSC) or transfer control to the
OS (OSHP).

acpi_get_hp_hw_control_from_firmware() is implemented when CONFIG_ACPI=y,
but does nothing if the current platform doesn't support ACPI.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

PCI: shpchp: Add shpchp_is_native()

In the same way we do for pciehp, add shpchp_is_native(), which returns
true if the bridge should be handled by the native SHPC driver. Then
convert the driver to use this function.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: pciehp: Make pciehp_is_native() stricter

Previously pciehp_is_native() returned true for any PCI device in a
hierarchy where _OSC says we can use pciehp. This is incorrect because
bridges without PCI_EXP_SLTCAP_HPC capability should be managed by acpiphp
instead.

Improve pciehp_is_native() to return true only when PCI_EXP_SLTCAP_HPC is
set and the pciehp driver is present. In any other case return false
to let acpiphp handle those.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[bhelgaas: remove NULL pointer check]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: Tidy comments

Remove pointless comments that tell us the file name, remove blank line
comments, follow multi-line comment conventions. No functional change
intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Add SPDX GPL-2.0 when no license was specified

b24413180f56 ("License cleanup: add SPDX GPL-2.0 license identifier to
files with no license") added SPDX GPL-2.0 to several PCI files that
previously contained no license information.

Add SPDX GPL-2.0 to all other PCI files that did not contain any license
information and hence were under the default GPL version 2 license of the
kernel.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PCI: Add wrappers for dev_printk()

Add PCI-specific dev_printk() wrappers and use them to simplify the code
slightly. No functional change intended.

Signed-off-by: Frederick Lawler <fred@fredlawl.com>
[bhelgaas: squash into one patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PCI: Bail early in acpi_pci_add_bus() if there is no ACPI handle

Hyper-V instances support PCI pass-through which is implemented through PV
pci-hyperv driver. When a device is passed through, a new root PCI bus is
created in the guest. The bus sits on top of VMBus and has no associated
information in ACPI. acpi_pci_add_bus() in this case proceeds all the way
to acpi_evaluate_dsm(), which reports

ACPI: \: failed to evaluate _DSM (0x1001)

While acpi_pci_slot_enumerate() and acpiphp_enumerate_slots() are protected
against ACPI_HANDLE() being NULL and do nothing, acpi_evaluate_dsm() is not
and gives us the error. It seems the correct fix is to not do anything in
acpi_pci_add_bus() in such cases.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PCI / PM: Rework acpi_pci_propagate_wakeup()

The acpi_pci_propagate_wakeup() routine is there to handle cases in
which PCI bridges (or PCIe ports) are expected to signal wakeup
for devices below them, but currently it doesn't do that correctly.

The problem is that acpi_pci_propagate_wakeup() uses
acpi_pm_set_device_wakeup() for bridges and if that routine is
called for multiple times to disable wakeup for the same device,
it will disable it on the first invocation and the next calls
will have no effect (it works analogously when called to enable
wakeup, but that is not a problem).

Now, say acpi_pci_propagate_wakeup() has been called for two
different devices under the same bridge and it has called
acpi_pm_set_device_wakeup() for that bridge each time. The
bridge is now enabled to generate wakeup signals. Next,
suppose that one of the devices below it resumes and
acpi_pci_propagate_wakeup() is called to disable wakeup for that
device. It will then call acpi_pm_set_device_wakeup() for the bridge
and that will effectively disable remote wakeup for all devices under
it even though some of them may still be suspended and remote wakeup
may be expected to work for them.

To address this (arguably theoretical) issue, allow
wakeup.enable_count under struct acpi_device to grow beyond 1 in
certain situations. In particular, allow that to happen in
acpi_pci_propagate_wakeup() when wakeup is enabled or disabled
for PCI bridges, so that wakeup is actually disabled for the
bridge when all devices under it resume and not when just one
of them does that.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

PM / core: Drop run_wake flag from struct dev_pm_info

The run_wake flag in struct dev_pm_info is used to indicate whether
or not the device is capable of generating remote wakeup signals at
run time (or in the system working state), but the distinction
between runtime remote wakeup and system wakeup signaling has always
been rather artificial. The only practical reason for it to exist
at the core level was that ACPI and PCI treated those two cases
differently, but that's not the case any more after recent changes.

For this reason, get rid of the run_wake flag and, when applicable,
use device_set_wakeup_capable() and device_can_wakeup() instead of
device_set_run_wake() and device_run_wake(), respectively.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / PM: Simplify device wakeup settings code

After previous changes it is not necessary to distinguish between
device wakeup for run time and device wakeup from system sleep states
any more, so rework the PCI device wakeup settings code accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / PM: Drop pme_interrupt flag from struct pci_dev

The pme_interrupt flag in struct pci_dev is set when PMEs generated
by the device are going to be signaled via root port PME interrupts.

Ironically enough, that information is only used by the code setting
up device wakeup through ACPI which returns as soon as it sees the
pme_interrupt flag set while setting up "remote runtime wakeup".
That is questionable, however, because in theory there may be PCIe
devices using out-of-band PME signaling under root ports handled
by the native PME code or devices requiring wakeup power setup to be
carried out by AML. For such devices, ACPI wakeup should be invoked
regardless of whether or not native PME signaling is used in general.

For this reason, drop the pme_interrupt flag and rework the code
using it which then allows the ACPI-based device wakeup handling
in PCI to be consolidated to use one code path for both "runtime
remote wakeup" and system wakeup (from sleep states).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PM: Consolidate device wakeup settings code

Currently, there are two separate ways of handling device wakeup
settings in the ACPI core, depending on whether this is runtime
wakeup or system wakeup (from sleep states). However, after the
previous commit eliminating the run_wake ACPI device wakeup flag,
there is no difference between the two any more at the ACPI level,
so they can be combined.

For this reason, introduce acpi_pm_set_device_wakeup() to replace both
acpi_pm_device_run_wake() and acpi_pm_device_sleep_wake() and make it
check the ACPI device object's wakeup.valid flag to determine whether
or not the device can be set up to generate wakeup signals.

Also notice that zpodd_enable/disable_run_wake() only call
device_set_run_wake() because acpi_pm_device_run_wake() called
device_run_wake(), which is not done by acpi_pm_set_device_wakeup(),
so drop the now redundant device_set_run_wake() calls from there.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PM: Drop run_wake from struct acpi_device_wakeup_flags

The run_wake flag in struct acpi_device_wakeup_flags stores the
information on whether or not the device can generate wakeup
signals at run time, but in ACPI that really is equivalent to
being able to generate wakeup signals at all.

In fact, run_wake will always be set after successful executeion of
acpi_setup_gpe_for_wake(), but if that fails, the device will not be
able to use a wakeup GPE at all, so it won't be able to wake up the
systems from sleep states too. Hence, run_wake actually means that
the device is capable of triggering wakeup and so it is equivalent
to the valid flag.

For this reason, drop run_wake from struct acpi_device_wakeup_flags
and make sure that the valid flag is only set if
acpi_setup_gpe_for_wake() has been successful.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PM: Run wakeup notify handlers synchronously

The work functions provided by the users of acpi_add_pm_notifier()
should be run synchronously before re-enabling the wakeup GPE in
case they are used to clear the status and/or disable the wakeup
signaling at the source. Otherwise, which is the case currently in
the PCI bus type code, the same wakeup event may be signaled for
multiple times while the execution of the work function in response
to it has already been queued up.

Fortunately, acpi_add_pm_notifier() is only used by PCI and by
ACPI device PM code internally, so the change is relatively
straightforward to make.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI: Switch to use generic guid_t in acpi_evaluate_dsm()

acpi_evaluate_dsm() and friends take a pointer to a raw buffer of 16
bytes. Instead we convert them to use guid_t type. At the same time we
convert current users.

acpi_str_to_uuid() becomes useless after the conversion and it's safe to
get rid of it.

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Yisen Zhuang <yisen.zhuang@huawei.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

PCI/ACPI: Provide acpi_get_rc_resources() for ARM64 platform

The acpi_get_rc_resources() is used to get the RC register address that can
not be described in MCFG. It takes the _HID & segment to look for and
outputs the RC address resource. Use PNP0C02 devices to describe such RC
address resource. Use _UID to match segment to tell which root bus the
PNP0C02 resource belongs to.

[bhelgaas: add dev argument, wrap in #ifdef CONFIG_PCI_QUIRKS]
Signed-off-by: Dongdong Liu <liudongdong3@huawei.com>
Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / hotplug / PCI: Make device_is_managed_by_native_pciehp() public

We're about to add runtime PM of hotplug ports, but we need to restrict it
to ports that are handled natively by the OS: If they're handled by the
firmware (which is the case for Thunderbolt on non-Macs), things would
break if the OS put the ports into D3hot behind the firmware's back.

To determine if a hotplug port is handled natively, one has to walk up from
the port to the root bridge and check the cached _OSC Control Field for the
value of the "PCI Express Native Hot Plug control" bit. There's already a
function to do that, device_is_managed_by_native_pciehp(), but it's private
to drivers/pci/hotplug/acpiphp_glue.c and only compiled in if
CONFIG_HOTPLUG_PCI_ACPI is enabled.

Make it public and move it to drivers/pci/pci-acpi.c, so that it is
available in the more general CONFIG_ACPI case.

The function contains a check if the device in question is a hotplug port
and returns false if it's not. The caller we're going to add doesn't need
this as it only calls the function if it actually *is* a hotplug port.
Move the check out of the function into the single existing caller.

Rename it to pciehp_is_native() and add some kerneldoc and polish.

No functional change intended.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: Query platform firmware for device power state

Usually the most accurate way to determine a PCI device's power state is to
read its PM Control & Status Register. There are two cases however when
this is not an option: If the device doesn't have the PM capability at
all, or if it is in D3cold (in which case its config space is
inaccessible).

In both cases, we can alternatively query the platform firmware for its
opinion on the device's power state. To facilitate this, augment struct
pci_platform_pm_ops with a ->get_power callback and implement it for
acpi_pci_platform_pm (the only pci_platform_pm_ops existing so far).

It is used by a forthcoming commit to let pci_update_current_state()
recognize D3cold.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

acpi: pci: Setup MSI domain for ACPI based pci devices

This patch introduces pci_msi_register_fwnode_provider() for irqchip
to register a callback, to provide a way to determine appropriate MSI
domain for a pci device.

It also introduces pci_host_bridge_acpi_msi_domain(), which returns
the MSI domain of the specified PCI host bridge with DOMAIN_BUS_PCI_MSI
bus token. Then, it is assigned to pci device.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

PCI / PM: constify pci_platform_pm_ops structure

The pci_platform_pm_ops structure is never modified, so declare it as
const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI / ACPI: Fix pci_acpi_optimize_delay() comment

The function takes ACPI handle, not the device itself. Fix the
comment

Signed-off-by: Srinidhi Kasagar <srinidhi.kasagar@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PM: Rework device power management to follow ACPI 6

The ACPI 6 specification has made some changes in the device power
management area. In particular:

* The D3hot power state is now supposed to be always available
(instead of D3cold) and D3cold is only regarded as valid if the
_PR3 object is present for the given device.

* The required ordering of transitions into power states deeper than
D0 is now such that for a transition into state Dx the _PSx method
is supposed to be executed first, if present, and the states of
the power resources the device depends on are supposed to be
changed after that.

* It is now explicitly forbidden to transition devices from
lower-power (deeper) into higher-power (shallower) power states
other than D0.

Those changes have been made so the specification reflects the
Windows' device power management code that the vast majority of
systems using ACPI is validated against.

To avoid artificial differences in ACPI device power management
between Windows and Linux, modify the ACPI device power management
code to follow the new specification. Add comments explaining the
code flow in some unclear places.

This only may affect some real corner cases in which the OS behavior
expected by the firmware is different from the Windows one, but that's
quite unlikely. The transition ordering change affects transitions
to D1 and D2 which are rarely used (if at all) and into D3hot and
D3cold for devices actually having _PR3, but those are likely to
be validated against Windows anyway. The other changes may affect
code calling acpi_device_get_power() or acpi_device_update_power()
where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD
(that's why the ACPI fan driver needs to be updated too) and since
transitions into ACPI_STATE_D3_HOT may remove power now, it is better
to avoid this one in acpi_pm_device_sleep_state() if the "no power
off" PM QoS flag is set.

The only existing user of acpi_device_can_poweroff() really cares
about the case when _PR3 is present, so the change in that function
should not cause any problems to happen too.

A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT
now and the compatibility with older systems should be covered
automatically.

In any case, if any real problems result from this, it still will
be better to follow the Windows' behavior (which now is reflected
by the specification too) in general and handle the cases when it
doesn't work via quirks.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI/ACPI: Optimize device state transition delays

The PCI "ACPI additions for FW latency optimizations" ECN (link below)
defines two functions in the PCI _DSM:

Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
host bridge. If it returns one, the OS may assume that all devices in
the hierarchy have already completed power-on reset delays.

Function 9, "Device Readiness Durations," applies only to the object
where it is located. It returns delay durations required after various
events if the device requires less time than the spec requires. Delays
from this function take precedence over the Reset Delay function.

Add support for Reset Delay and part of Device Readiness Durations.

[bhelgaas: changelog, comments]
Link: https://www.pcisig.com/specifications/conventional/pci_firmware/ECN_fw_latency_optimization_final.pdf
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Make a shareable UUID for PCI firmware ACPI _DSM

The PCI Firmware Specification, r3.0, sec 4.6.4.1.3, defines a single UUID
for an ACPI _DSM method to provide device-specific control functions. This
_DSM method support several functions, including PCI Express Slot
Information, PCI Express Slot Number, PCI Bus Capabilities, etc.

Move the UUID definition from pci/pci-label.c, where it could be used only
for one function, to pci/pci-acpi.c where it can be shared for all these
functions.

[bhelgaas: changelog]
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: Don't look for ACPI hotplug parameters if ACPI is disabled

Booting a v3.18 or newer Xen domU kernel with PCI devices passed through
results in an oops (this is a 32-bit 3.13.11 dom0 with a 64-bit 4.4.0
hypervisor and 32-bit domU):

BUG: unable to handle kernel paging request at 0030303e
IP: [<c06ed0e6>] acpi_ns_validate_handle+0x12/0x1a
Call Trace:
[<c06eda4d>] ? acpi_evaluate_object+0x31/0x1fc
[<c06b78e1>] ? pci_get_hp_params+0x111/0x4e0
[<c0407bc7>] ? xen_force_evtchn_callback+0x17/0x30
[<c04085fb>] ? xen_restore_fl_direct_reloc+0x4/0x4
[<c0699d34>] ? pci_device_add+0x24/0x450

Don't look for ACPI configuration information if ACPI has been disabled.

I don't think this is the best fix, because we can boot plain Linux (no
Xen) with "acpi=off", and we don't need this check in pci_get_hp_params().
There should be a better fix that would make Xen domU work the same way.
The domU kernel has ACPI support but it has no AML. There should be a way
to initialize the ACPI data structures so things fail gracefully rather
than oopsing. This is an interim fix to address the regression.

Fixes: 6cd33649fa83 ("PCI: Add pci_configure_device() during enumeration")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=96301
Reported-by: Michael D Labriola <mlabriol@gdeb.com>
Tested-by: Michael D Labriola <mlabriol@gdeb.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org # v3.18+

PCI / PM: Avoid resuming PCI devices during system suspend

Commit f25c0ae2b4c4 (ACPI / PM: Avoid resuming devices in ACPI PM
domain during system suspend) modified the ACPI PM domain's system
suspend callbacks to allow devices attached to it to be left in the
runtime-suspended state during system suspend so as to optimize
the suspend process.

This was based on the general mechanism introduced by commit
aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended
devices unnecessarily).

Extend that approach to PCI devices by modifying the PCI bus type's
->prepare callback to return 1 for devices that are runtime-suspended
when it is being executed and that are in a suitable power state and
need not be resumed going forward.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Delete unnecessary NULL pointer checks

The functions pci_dev_put(), pci_pme_wakeup_bus(), and put_device() return
immediately if their argument is NULL. Thus the test before the call is
not needed.

Remove these unnecessary tests.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Shuffle pci-acpi.c functions to group them logically

Move code around to put all the ACPI power management stuff together and
all the pieces related to ACPI methods (_CBA, _HPP, _HPX) together.

No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Whitespace cleanup in pci-acpi.c

Whitespace fixes only; no functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Move pci_get_hp_params() to drivers/pci/pci-acpi.c

Move pci_get_hp_params() and related functions from
drivers/pci/hotplug/acpi_pcihp.c to drivers/pci/pci-acpi.c.

Previously, pci_get_hp_params() was used only by hotplug drivers. But
future changes will move this into the normal device enumeration process,
so it will be used even when CONFIG_HOTPLUG_PCI is not set.

No functional change.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PCI: Use ACPI_COMPANION() instead of ACPI_HANDLE()

The ACPI_HANDLE() macro evaluates ACPI_COMPANION() internally to
return the handle of the device's ACPI companion, so it is much
more straightforward and efficient to use ACPI_COMPANION()
directly to obtain the device's ACPI companion object instead of
using ACPI_HANDLE() and acpi_bus_get_device() on the returned
handle for the same thing.

Use ACPI_COMPANION() instead of ACPI_HANDLE() in the PCI ACPI support
code.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI / PM: Revork the handling of ACPI device wakeup notifications

Since ACPI wakeup GPEs are going to be enabled during system suspend
as well as for runtime wakeup by a subsequent patch and the same
notify handlers will be used in both cases, rework the ACPI device
wakeup notification framework so that the part specific to physical
devices is always run asynchronously from the PM workqueue. This
prevents runtime resume callbacks for those devices from being
run during system suspend and resume which may not be appropriate,
among other things.

Also make ACPI device wakeup notification handling a bit more robust
agaist subsequent removal of ACPI device objects, whould that ever
happen, and create a wakeup source object for each ACPI device
configured for wakeup so that wakeup notifications for those
devices can wake up the system from the "freeze" sleep state.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: Use pci_is_bridge() to simplify code

Use pci_is_bridge() to simplify code. No functional change.

Requires: 326c1cdae741 PCI: Rename pci_is_bridge() to pci_has_subordinate()
Requires: 1c86438c9423 PCI: Add new pci_is_bridge() interface
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI / ACPI: Install wakeup notify handlers for all PCI devs with ACPI

It turns out that some BIOSes don't report wakeup GPEs through
_PRW, but use them for signaling wakeup anyway, which causes GPE
storms to occur on some systems after resume from system suspend.
This issue has been uncovered by commit d2e5f0c16ad6 (ACPI / PCI:
Rework the setup and cleanup of device wakeup) during the 3.9
development cycle.

Work around the problem by installing wakeup notify handlers for all
PCI devices with ACPI support (i.e. having ACPI companions) regardless
of whether or not the BIOS reports ACPI wakeup support for them. The
presence of the wakeup notify handlers alone is not harmful in any
way if there are no events for them to handle (they are simply never
executed then), but on some systems they are needed to take care of
spurious events.

Fixes: d2e5f0c16ad6 (ACPI / PCI: Rework the setup and cleanup of device wakeup)
References: https://bugzilla.kernel.org/show_bug.cgi?id=63021
Reported-and-tested-by: Agustin Barto <abarto@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI: Use dev_is_pci() to identify PCI devices

Use dev_is_pci() instead of checking bus type directly.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / bind: Rework struct acpi_bus_type

Replace the .find_device function pointer in struct acpi_bus_type
with a new one, .find_companion, that is supposed to point to a
function returning struct acpi_device pointer (instead of an int)
and takes one argument (instead of two). This way the role of
this callback is more clear and the implementation of it can
be more straightforward.

Update all of the users of struct acpi_bus_type (PCI, PNP/ACPI and
USB) to reflect the structure change.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI

PCI / ACPI: Use acpi_find_child_device() for child devices lookup

It is much more efficient to use acpi_find_child_device()
for child devices lookup in acpi_pci_find_device() and pass
ACPI_COMPANION(dev->parent) to it directly instead of obtaining
ACPI_HANDLE() of ACPI_COMPANION(dev->parent) and passing it to
acpi_find_child() which has to run acpi_bus_get_device() to
obtain ACPI_COMPANION(dev->parent) from that again.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>

ACPI: Clean up inclusions of ACPI header files

Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.

First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
should not be included directly from any files that are built for
CONFIG_ACPI unset, because that generally leads to build warnings about
undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set,
<linux/acpi.h> includes those files and for CONFIG_ACPI unset it
provides stub ACPI symbols to be used in that case.

Second, there are ordering dependencies between those files that always
have to be met. Namely, it is required that <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there. And <acpi/acpi.h> which provides
basic ACPICA type declarations should always be included prior to any other
ACPI headers in CONFIG_ACPI builds. That also is taken care of including
<linux/acpi.h> as appropriate.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI: Eliminate the DEVICE_ACPI_HANDLE() macro

Since DEVICE_ACPI_HANDLE() is now literally identical to
ACPI_HANDLE(), replace it with the latter everywhere and drop its
definition from include/acpi.h.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

PCI: Fix whitespace, capitalization, and spelling errors

Fix whitespace, capitalization, and spelling errors. No functional change.
I know "busses" is not an error, but "buses" was more common, so I used it
consistently.

Signed-off-by: Marta Rybczynska <rybczynska@gmail.com> (pci_reset_bridge_secondary_bus())
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

pci-acpi: convert acpi_get_handle() to acpi_has_method()

acpi_has_method() is a new ACPI API introduced to check
the existence of an ACPI control method.

It can be used to replace acpi_get_handle() in the case that
1. the calling function doesn't need the ACPI handle of the control method.
and
2. the calling function doesn't care the reason why the method is unavailable.

Convert acpi_get_handle() to acpi_has_method()
in drivers/pci/pci-acpi.c in this patch.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
CC: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PCI / ACPI / PM: Clear pme_poll for devices in D3cold on wakeup

Commit 448bd85 (PCI/PM: add PCIe runtime D3cold support) added a
piece of code to pci_acpi_wake_dev() causing that function to behave
in a special way for devices in D3cold (so that their configuration
registers are not accessed before those devices are resumed).
However, it didn't take the clearing of the pme_poll flag into
account. That has to be done for all devices, even if they are in
D3cold, or pci_pme_list_scan() will not know that wakeup has been
signaled for the device and will poll its PME Status bit
unnecessarily.

Fix the problem by moving the clearing of the pme_poll flag in
pci_acpi_wake_dev() before the code introduced by commit 448bd85.

Reported-and-tested-by: David E. Box <david.e.box@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: 3.6+ <stable@vger.kernel.org> # 3.6+

ACPI: Try harder to resolve _ADR collisions for bridges

In theory, under a given ACPI namespace node there should be only
one child device object with _ADR whose value matches a given bus
address exactly. In practice, however, there are systems in which
multiple child device objects under a given parent have _ADR matching
exactly the same address. In those cases we use _STA to determine
which of the multiple matching devices is enabled, since some systems
are known to indicate which ACPI device object to associate with the
given physical (usually PCI) device this way.

Unfortunately, as it turns out, there are systems in which many
device objects under the same parent have _ADR matching exactly the
same bus address and none of them has _STA, in which case they all
should be regarded as enabled according to the spec. Still, if
those device objects are supposed to represent bridges (e.g. this
is the case for device objects corresponding to PCIe ports), we can
try harder and skip the ones that have no child device objects in the
ACPI namespace. With luck, we can avoid using device objects that we
are not expected to use this way.

Although this only works for bridges whose children also have ACPI
namespace representation, it is sufficient to address graphics
adapter detection issues on some systems, so rework the code finding
a matching device ACPI handle for a given bus address to implement
this idea.

Introduce a new function, acpi_find_child(), taking three arguments:
the ACPI handle of the device's parent, a bus address suitable for
the device's bus type and a bool indicating if the device is a
bridge and make it work as outlined above. Reimplement the function
currently used for this purpose, acpi_get_child(), as a call to
acpi_find_child() with the last argument set to 'false' and make
the PCI subsystem use acpi_find_child() with the bridge information
passed as the last argument to it. [Lan Tianyu notices that it is
not sufficient to use pci_is_bridge() for that, because the device's
subordinate pointer hasn't been set yet at this point, so use
hdr_type instead.]

This change fixes a regression introduced inadvertently by commit
33f767d (ACPI: Rework acpi_get_child() to be more efficient) which
overlooked the fact that for acpi_walk_namespace() "post-order" means
"after all children have been visited" rather than "on the way back",
so for device objects without children and for namespace walks of
depth 1, as in the acpi_get_child() case, the "post-order" callbacks
ordering is actually the same as the ordering of "pre-order" ones.
Since that commit changed the namespace walk in acpi_get_child() to
terminate after finding the first matching object instead of going
through all of them and returning the last one, it effectively
changed the result returned by that function in some rare cases and
that led to problems (the switch from a "pre-order" to a "post-order"
callback was supposed to prevent that from happening, but it was
ineffective).

As it turns out, the systems where the change made by commit
33f767d actually matters are those where there are multiple ACPI
device objects representing the same PCIe port (which effectively
is a bridge). Moreover, only one of them, and the one we are
expected to use, has child device objects in the ACPI namespace,
so the regression can be addressed as described above.

References: https://bugzilla.kernel.org/show_bug.cgi?id=60561
Reported-by: Peter Wu <lekensteyn@gmail.com>
Tested-by: Vladimir Lalov <mail@vlalov.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+

PCI / ACPI: Use dev_dbg() instead of dev_info() in acpi_pci_set_power_state()

acpi_pci_set_power_state() uses dev_info() to print diagnostic
messages regarding ACPI power state changes of devices, but that
results in too much not really interesting output into the kernel
log in some cases.

For this reason, change it to use dev_dbg() instead and prevent
kernel log from being spammed.

[rjw: Changelog]
References: https://bugzilla.kernel.org/show_bug.cgi?id=60636
Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI / PCI: Make bus registration and unregistration symmetric

Since acpi_pci_slot_enumerate() and acpiphp_enumerate_slots() can get
the ACPI device handle they need from bus->bridge, it is not
necessary to pass that handle to them as an argument.

Drop the second argument of acpi_pci_slot_enumerate() and
acpiphp_enumerate_slots(), rework them to obtain the ACPI handle
from bus->bridge and make acpi_pci_add_bus() and
acpi_pci_remove_bus() entirely symmetrical.

Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>

PCI / ACPI / PM: Use correct power state strings in messages

Make acpi_pci_set_power_state() print the name of the ACPI device
power state the device has been actually put into instead of printing
the name of the requested PCI device power state, which need not be
the same.

[bhelgaas: use ACPI_STATE_D3_COLD (ACPI_STATE_D3 == ACPI_STATE_D3_COLD)]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: Replace printks with appropriate pr_*()

Replace deprecated printk(KERN_ERR...) with pr_err() in pci-acpi.c

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI: acpiphp: Do not use ACPI PCI subdriver mechanism

Previously the acpiphp driver registered itself as an ACPI PCI subdriver,
so its callbacks were invoked when creating/destroying PCI root
buses to manage ACPI-based PCI hotplug slots. But it doesn't handle
P2P bridge hotplug events, so it will cause strange behaviour if there
are hotplug slots associated with a hot-removed P2P bridge.

This patch fixes this issue by:
1) Directly hooking into PCI core to update hotplug slot devices when
creating/destroying PCI buses through:
pci_{add|remove}_bus() -> acpi_pci_{add|remove}_bus()
2) Getting rid of unused ACPI PCI subdriver-related code

It also cleans up unused code in the acpiphp driver.

[bhelgaas: keep acpi_pci_add_bus() stub for CONFIG_ACPI=n]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>

PCI/ACPI: Handle PCI slot devices when creating/destroying PCI buses

Currently the pci_slot driver doesn't update PCI slot devices when PCI
device hotplug event happens, which may cause memory leak and returning
stale information to user.

Now the pci_slot driver has been changed as built-in driver, so invoke
PCI slot enumeration and destroy routines directly from the PCI core.
And remove ACPI PCI sub-driver related code because it isn't needed
any more.

[bhelgas: removed "extern" from function declarations]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>

PCI/ACPI: Prepare stub functions to handle ACPI PCI (hotplug) slots

Prepare two stub functions to handle ACPI PCI slots and ACPI PCI hotplug
slots, which will be invoked by the PCI core when creating/destroying
PCI buses.

It will be used to get rid of ACPI PCI subdrivers for pci_slot and
acpiphp, and eventually remove the ACPI PCI subdriver mechanism.

And it will also be used to handle ACPI PCI (hotplug) slots in a unified
way, both at boot time and for PCI hotplug operations.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Myron Stowe <myron.stowe@redhat.com>

PCI/ACPI: Always resume devices on ACPI wakeup notifications

It turns out that the _Lxx control methods provided by some BIOSes
clear the PME Status bit of PCI devices they handle, which means that
pci_acpi_wake_dev() cannot really use that bit to check whether or
not the device has signalled wakeup.

One symptom of the problem is, for example, that when an affected PCI
USB controller is runtime-suspended, then plugging in a new USB device
into one of the controller's ports will not wake up the controller,
which should happen.

For this reason, make pci_acpi_wake_dev() always attempt to resume
the device it is called for regardless of the device's PME Status bit
value (that bit still has to be cleared if set at this point,
though).

Reported-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Matthew Garrett <mjg59@srcf.ucam.org>
CC: stable@vger.kernel.org # v3.7+

ACPI / glue: Add .match() callback to struct acpi_bus_type

USB uses the .find_bridge() callback from struct acpi_bus_type
incorrectly, because as a result of the way it is used by USB every
device in the system that doesn't have a bus type or parent is
passed to usb_acpi_find_device() for inspection.

What USB actually needs, though, is to call usb_acpi_find_device()
for USB ports that don't have a bus type defined, but have
usb_port_device_type as their device type, as well as for USB
devices.

To fix that replace the struct bus_type pointer in struct
acpi_bus_type used for matching devices to specific subsystems
with a .match() callback to be used for this purpose and update
the users of struct acpi_bus_type, including USB, accordingly.
Define the .match() callback routine for USB, usb_acpi_bus_match(),
in such a way that it will cover both USB devices and USB ports
and remove the now redundant .find_bridge() callback pointer from
usb_acpi_bus.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>

PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers

Previously, we cached _PRT (PCI routing table, ACPI 5.0 sec 6.2.12)
contents and associated each _PRT entry with a PCI bus number. The bus
number association means dependencies on PCI device enumeration and bus
number assignment, as well as on the PCI/ACPI binding process.

After 4f535093cf ("PCI: Put pci_dev in device tree as early as possible"),
these dependencies caused the IRQ issues reported by Peter:

pci 0000:00:1e.0: PCI bridge to [bus 09] (subtractive decode)
pci 0000:00:1e.0: can't derive routing for PCI INT A
snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
irq 18: nobody cared (try booting with the "irqpoll" option)

This patch removes _PRT caching. Instead, we evaluate _PRT as needed
in the pci_enable_device() path. This also removes the dependency on
PCI bus numbers: we can simply look at the _PRT associated with each
bridge as we walk upstream toward the root.

[bhelgaas: changelog]
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=53561
Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PM: Rework the handling of devices depending on power resources

Commit 0090def6 (ACPI: Add interface to register/unregister device
to/from power resources) made it possible to indicate to the ACPI
core that if the given device depends on any power resources, then
it should be resumed as soon as all of the power resources required
by it to transition to the D0 power state have been turned on.

Unfortunately, however, this was a mistake, because all devices
depending on power resources should be treated this way (i.e. they
should be resumed when all power resources required by their D0
state have been turned on) and for the majority of those devices
the ACPI core can figure out by itself which (physical) devices
depend on what power resources.

For this reason, replace the code added by commit 0090def6 with a
new, much more straightforward, mechanism that will be used
internally by the ACPI core and remove all references to that code
from kernel subsystems using ACPI.

For the cases when there are (physical) devices that should be
resumed whenever a not directly related ACPI device node goes into
D0 as a result of power resources configuration changes, like in
the SATA case, add two new routines, acpi_dev_pm_add_dependent()
and acpi_dev_pm_remove_dependent(), allowing subsystems to manage
such dependencies. Convert the SATA subsystem to use the new
functions accordingly.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

ACPI / PCI: Set root bridge ACPI handle in advance

The ACPI handles of PCI root bridges need to be known to
acpi_bind_one(), so that it can create the appropriate
"firmware_node" and "physical_node" files for them, but currently
the way it gets to know those handles is not exactly straightforward
(to put it lightly).

This is how it works, roughly:

1. acpi_bus_scan() finds the handle of a PCI root bridge,
creates a struct acpi_device object for it and passes that
object to acpi_pci_root_add().

2. acpi_pci_root_add() creates a struct acpi_pci_root object,
populates its "device" field with its argument's address
(device->handle is the ACPI handle found in step 1).

3. The struct acpi_pci_root object created in step 2 is passed
to pci_acpi_scan_root() and used to get resources that are
passed to pci_create_root_bus().

4. pci_create_root_bus() creates a struct pci_host_bridge object
and passes its "dev" member to device_register().

5. platform_notify(), which for systems with ACPI is set to
acpi_platform_notify(), is called.

So far, so good. Now it starts to be "interesting".

6. acpi_find_bridge_device() is used to find the ACPI handle of
the given device (which is the PCI root bridge) and executes
acpi_pci_find_root_bridge(), among other things, for the
given device object.

7. acpi_pci_find_root_bridge() uses the name (sic!) of the given
device object to extract the segment and bus numbers of the PCI
root bridge and passes them to acpi_get_pci_rootbridge_handle().

8. acpi_get_pci_rootbridge_handle() browses the list of ACPI PCI
root bridges and finds the one that matches the given segment
and bus numbers. Its handle is then used to initialize the
ACPI handle of the PCI root bridge's device object by
acpi_bind_one(). However, this is *exactly* the ACPI handle we
started with in step 1.

Needless to say, this is quite embarassing, but it may be avoided
thanks to commit f3fd0c8 (ACPI: Allow ACPI handles of devices to be
initialized in advance), which makes it possible to initialize the
ACPI handle of a device before passing it to device_register().

Accordingly, add a new __weak routine, pcibios_root_bridge_prepare(),
defaulting to an empty implementation that can be replaced by the
interested architecutres (x86 and ia64 at the moment) with functions
that will set the root bridge's ACPI handle before its dev member is
passed to device_register(). Make both x86 and ia64 provide such
implementations of pcibios_root_bridge_prepare() and remove
acpi_pci_find_root_bridge() and acpi_get_pci_rootbridge_handle() that
aren't necessary any more.

Included is a fix for breakage on systems with non-ACPI PCI host
bridges from Bjorn Helgaas.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PCI: Move the _PRT setup and cleanup code to pci-acpi.c

Move the code related to _PRT setup and removal and to power
resources from acpi_pci_bind() and acpi_pci_unbind() to the .setup()
and .cleanup() callbacks in acpi_pci_bus and remove acpi_pci_bind()
and acpi_pci_unbind() that have no purpose any more. Accordingly,
remove the code related to device .bind() and .unbind() operations
from the ACPI PCI root bridge driver.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>

ACPI / PCI: Rework the setup and cleanup of device wakeup

Currently, the ACPI wakeup capability of PCI devices is set up
in two different places, partially in acpi_pci_bind() where
runtime wakeup is initialized and partially in
platform_pci_wakeup_init(), where system wakeup is initialized.
The cleanup is only done in acpi_pci_unbind() and it only covers
runtime wakeup.

Use the new .setup() and .cleanup() callbacks in struct acpi_bus_type
to consolidate that code and do the setup and the cleanup each in one
place.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Toshi Kani <toshi.kani@hp.com>

ACPI / PM: Move routines for adding/removing device wakeup notifiers

ACPI routines for adding and removing device wakeup notifiers are
currently defined in a PCI-specific file, but they will be necessary
for non-PCI devices too, so move them to a separate file under
drivers/acpi and rename them to indicate their ACPI origins.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

PM / ACPI: Take device PM QoS flags into account

Make ACPI power management routines and PCI power management
routines depending on ACPI take device PM QoS flags into account
when deciding what power state to put the device into.

In particular, after this change acpi_pm_device_sleep_state() will
not return ACPI_STATE_D3_COLD as the deepest available low-power
state if PM_QOS_FLAG_NO_POWER_OFF is requested for the device and it
will not require remote wakeup to work for the device in the returned
low-power state if there is at least one PM QoS flags request for the
device, but PM_QOS_FLAG_REMOTE_WAKEUP is not requested for it.

Accordingly, acpi_pci_set_power_state() will refuse to put the
device into D3cold if PM_QOS_FLAG_NO_POWER_OFF is requested for it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>

PCI / PM: Fix D3/D3cold/D4 messages printed by acpi_pci_set_power_state()

If a PCI device is put into D3_cold by acpi_bus_set_power(),
the message printed by acpi_pci_set_power_state() says that its
power state has been changed to D4, which doesn't make sense.
In turn, if the device is put into D3_hot, the message simply
says "D3" without specifying the variant of the D3 state.

Fix this by using the pci_power_name() macro for printing the state
name instead of building it from the numeric value corresponding to
the given state directly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/PM: add PCIe runtime D3cold support

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>

ACPI/PM: specify lowest allowed state for device sleep state

Lower device sleep state can save more power, but has more exit
latency too. Sometimes, to satisfy some power QoS and other
requirement, we need to constrain the lowest device sleep state.

In this patch, a parameter to specify lowest allowed state for
acpi_pm_device_sleep_state is added. So that the caller can enforce
the constraint via the parameter.

This is needed by PCIe D3cold support, where the lowest power state
allowed may be D3_HOT instead of default D3_COLD.

CC: Len Brown <lenb@kernel.org>
CC: linux-acpi@vger.kernel.org
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

PCI/ACPI: provide MMCONFIG address for PCI host bridges

This patch provide MMCONFIG address for PCI host bridges, which will
be used to support host bridge hotplug. It gets MMCONFIG address
by evaluating _CBA method if available.

Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jiang Liu <liuj97@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

ACPI / PCI / PM: Fix device PM regression related to D3hot/D3cold

Commit 1cc0c998fdf2 ("ACPI: Fix D3hot v D3cold confusion") introduced a
bug in __acpi_bus_set_power() and changed the behavior of
acpi_pci_set_power_state() in such a way that it generally doesn't work
as expected if PCI_D3hot is passed to it as the second argument.

First off, if ACPI_STATE_D3 (equal to ACPI_STATE_D3_COLD) is passed to
__acpi_bus_set_power() and the explicit_set flag is set for the D3cold
state, the function will try to execute AML method called "_PS4", which
doesn't exist.

Fix this by adding a check to ensure that the name of the AML method
to execute for transitions to ACPI_STATE_D3_COLD is correct in
__acpi_bus_set_power(). Also make sure that the explicit_set flag
for ACPI_STATE_D3_COLD will be set if _PS3 is present and modify
acpi_power_transition() to avoid accessing power resources for
ACPI_STATE_D3_COLD, because they don't exist.

Second, if PCI_D3hot is passed to acpi_pci_set_power_state() as the
target state, the function will request a transition to
ACPI_STATE_D3_HOT instead of ACPI_STATE_D3. However,
ACPI_STATE_D3_HOT is now only marked as supported if the _PR3 AML
method is defined for the given device, which is rare. This causes
problems to happen on systems where devices were successfully put
into ACPI D3 by pci_set_power_state(PCI_D3hot) which doesn't work
now. In particular, some unused graphics adapters are not turned
off as a result.

To fix this issue restore the old behavior of
acpi_pci_set_power_state(), which is to request a transition to
ACPI_STATE_D3 (equal to ACPI_STATE_D3_COLD) if either PCI_D3hot or
PCI_D3cold is passed to it as the argument.

This approach is not ideal, because generally power should not
be removed from devices if PCI_D3hot is the target power state,
but since this behavior is relied on, we have no choice but to
restore it at the moment and spend more time on designing a
better solution in the future.

References: https://bugzilla.kernel.org/show_bug.cgi?id=43228
Reported-by: rocko <rockorequin@hotmail.com>
Reported-by: Cristian Rodríguez <crrodriguez@opensuse.org>
Reported-and-tested-by: Peter <lekensteyn@gmail.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ACPI: Fix D3hot v D3cold confusion

Before this patch, ACPI_STATE_D3 incorrectly referenced D3hot
in some places, but D3cold in other places.

After this patch, ACPI_STATE_D3 always means ACPI_STATE_D3_COLD;
and all references to D3hot use ACPI_STATE_D3_HOT.

ACPI's _PR3 method is used to enter both D3hot and D3cold states.
What distinguishes D3hot from D3cold is the presence _PR3
(Power Resources for D3hot) If these resources are all ON,
then the state is D3hot. If _PR3 is not present,
or all _PR0 resources for the devices are OFF,
then the state is D3cold.

This patch applies after Linux-3.4-rc1.
A future syntax cleanup may remove ACPI_STATE_D3
to emphasize that it always means ACPI_STATE_D3_COLD.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI, PCI: Move acpi_dev_run_wake() to ACPI core

acpi_dev_run_wake() is a generic function which can be used by
other subsystem too. Rename it to acpi_pm_device_run_wake, to be
consistent with acpi_pm_device_sleep_wake.

Then move it to ACPI core.

Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI/ACPI/PM: Avoid resuming devices that don't signal PME

Modify pci_acpi_wake_dev() to avoid resuming PME-capable devices
whose PME Status bits are not set, which may happen currently if
several devices are associated with the same wakeup GPE and all
of them are notified whenever at least one of them signals PME.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: Rework ASPM disable code

Right now we forcibly clear ASPM state on all devices if the BIOS indicates
that the feature isn't supported. Based on the Microsoft presentation
"PCI Express In Depth for Windows Vista and Beyond", I'm starting to think
that this may be an error. The implication is that unless the platform
grants full control via _OSC, Windows will not touch any PCIe features -
including ASPM. In that case clearing ASPM state would be an error unless
the platform has granted us that control.

This patch reworks the ASPM disabling code such that the actual clearing
of state is triggered by a successful handoff of PCIe control to the OS.
The general ASPM code undergoes some changes in order to ensure that the
ability to clear the bits isn't overridden by ASPM having already been
disabled. Further, this theoretically now allows for situations where
only a subset of PCIe roots hand over control, leaving the others in the
BIOS state.

It's difficult to know for sure that this is the right thing to do -
there's zero public documentation on the interaction between all of these
components. But enough vendors enable ASPM on platforms and then set this
bit that it seems likely that they're expecting the OS to leave them alone.

Measured to save around 5W on an idle Thinkpad X220.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI/ACPI/PM: Avoid resuming devices that don't signal PME

Modify pci_acpi_wake_dev() to avoid resuming PME-capable devices
whose PME Status bits are not set, which may happen currently if
several devices are associated with the same wakeup GPE and all
of them are notified whenever at least one of them signals PME.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: Rework ASPM disable code

Right now we forcibly clear ASPM state on all devices if the BIOS indicates
that the feature isn't supported. Based on the Microsoft presentation
"PCI Express In Depth for Windows Vista and Beyond", I'm starting to think
that this may be an error. The implication is that unless the platform
grants full control via _OSC, Windows will not touch any PCIe features -
including ASPM. In that case clearing ASPM state would be an error unless
the platform has granted us that control.

This patch reworks the ASPM disabling code such that the actual clearing
of state is triggered by a successful handoff of PCIe control to the OS.
The general ASPM code undergoes some changes in order to ensure that the
ability to clear the bits isn't overridden by ASPM having already been
disabled. Further, this theoretically now allows for situations where
only a subset of PCIe roots hand over control, leaving the others in the
BIOS state.

It's difficult to know for sure that this is the right thing to do -
there's zero public documentation on the interaction between all of these
components. But enough vendors enable ASPM on platforms and then set this
bit that it seems likely that they're expecting the OS to leave them alone.

Measured to save around 5W on an idle Thinkpad X220.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI / PM: Remove unnecessary error variable from acpi_dev_run_wake()

The result returned by acpi_dev_run_wake() is always either -EINVAL
or -ENODEV, while obviously it should return 0 on success. The
problem is that the leftover error variable, that's not really used
in the function, is initialized with -ENODEV and then returned
without modification.

To fix this issue remove the error variable from acpi_dev_run_wake()
and make the function return 0 on success as appropriate.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI / PM: Extend PME polling to all PCI devices

The land of PCI power management is a land of sorrow and ugliness,
especially in the area of signaling events by devices. There are
devices that set their PME Status bits, but don't really bother
to send a PME message or assert PME#. There are hardware vendors
who don't connect PME# lines to the system core logic (they know
who they are). There are PCI Express Root Ports that don't bother
to trigger interrupts when they receive PME messages from the devices
below. There are ACPI BIOSes that forget to provide _PRW methods for
devices capable of signaling wakeup. Finally, there are BIOSes that
do provide _PRW methods for such devices, but then don't bother to
call Notify() for those devices from the corresponding _Lxx/_Exx
GPE-handling methods. In all of these cases the kernel doesn't have
a chance to receive a proper notification that it should wake up a
device, so devices stay in low-power states forever. Worse yet, in
some cases they continuously send PME Messages that are silently
ignored, because the kernel simply doesn't know that it should clear
the device's PME Status bit.

This problem was first observed for "parallel" (non-Express) PCI
devices on add-on cards and Matthew Garrett addressed it by adding
code that polls PME Status bits of such devices, if they are enabled
to signal PME, to the kernel. Recently, however, it has turned out
that PCI Express devices are also affected by this issue and that it
is not limited to add-on devices, so it seems necessary to extend
the PME polling to all PCI devices, including PCI Express and planar
ones. Still, it would be wasteful to poll the PME Status bits of
devices that are known to receive proper PME notifications, so make
the kernel (1) poll the PME Status bits of all PCI and PCIe devices
enabled to signal PME and (2) disable the PME Status polling for
devices for which correct PME notifications are received.

Tested-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI: Add D3 cold state

_SxW returns an Integer containing the lowest D-state supported in state
Sx. If OSPM has not indicated that it supports _PR3, then the value “3”
corresponds to D3. If it has indicated _PR3 support, the value “3”
represents D3hot and the value “4” represents D3cold.

Linux does set _OSC._PR3, so we should fix it to expect that _SxW can
return 4.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI: Remove the wakeup.run_wake_count device field

The wakeup.run_wake_count ACPI device field is only used by the PCI
runtime PM code to "protect" devices from being prepared for
generating wakeup signals more than once in a row. However, it
really doesn't provide any protection, because (1) all of the
functions it is supposed to protect use their own reference counters
effectively ensuring that the device will be set up for generating
wakeup signals just once and (2) the PCI runtime PM code uses
wakeup.run_wake_count in a racy way, since nothing prevents
acpi_dev_run_wake() from being called concurrently from two different
threads for the same device.

Remove the wakeup.run_wake_count ACPI device field which is
unnecessary, confusing and used in a wrong way.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

PCI/PM: Report wakeup events before resuming devices

Make wakeup events be reported by the PCI subsystem before attempting to
resume devices or queuing up runtime resume requests for them, because
wakeup events should be reported as soon as they have been detected.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: Disable ASPM if BIOS asks us to

We currently refuse to touch the ASPM registers if the BIOS tells us that
ASPM isn't supported. This can cause problems if the BIOS has (for any
reason) enabled ASPM on some devices anyway. Change the code such that we
explicitly clear ASPM if the FADT indicates that ASPM isn't supported,
and make sure we tidy up appropriately on device removal in order to deal
with the hotplug case. If ASPM is disabled because the BIOS doesn't hand
over control then we won't touch the registers.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PM: Make it possible to avoid races between wakeup and system sleep

One of the arguments during the suspend blockers discussion was that
the mainline kernel didn't contain any mechanisms making it possible
to avoid races between wakeup and system suspend.

Generally, there are two problems in that area. First, if a wakeup
event occurs exactly when /sys/power/state is being written to, it
may be delivered to user space right before the freezer kicks in, so
the user space consumer of the event may not be able to process it
before the system is suspended. Second, if a wakeup event occurs
after user space has been frozen, it is not generally guaranteed that
the ongoing transition of the system into a sleep state will be
aborted.

To address these issues introduce a new global sysfs attribute,
/sys/power/wakeup_count, associated with a running counter of wakeup
events and three helper functions, pm_stay_awake(), pm_relax(), and
pm_wakeup_event(), that may be used by kernel subsystems to control
the behavior of this attribute and to request the PM core to abort
system transitions into a sleep state already in progress.

The /sys/power/wakeup_count file may be read from or written to by
user space. Reads will always succeed (unless interrupted by a
signal) and return the current value of the wakeup events counter.
Writes, however, will only succeed if the written number is equal to
the current value of the wakeup events counter. If a write is
successful, it will cause the kernel to save the current value of the
wakeup events counter and to abort the subsequent system transition
into a sleep state if any wakeup events are reported after the write
has returned.

[The assumption is that before writing to /sys/power/state user space
will first read from /sys/power/wakeup_count. Next, user space
consumers of wakeup events will have a chance to acknowledge or
veto the upcoming system transition to a sleep state. Finally, if
the transition is allowed to proceed, /sys/power/wakeup_count will
be written to and if that succeeds, /sys/power/state will be written
to as well. Still, if any wakeup events are reported to the PM core
by kernel subsystems after that point, the transition will be
aborted.]

Additionally, put a wakeup events counter into struct dev_pm_info and
make these per-device wakeup event counters available via sysfs,
so that it's possible to check the activity of various wakeup event
sources within the kernel.

To illustrate how subsystems can use pm_wakeup_event(), make the
low-level PCI runtime PM wakeup-handling code use it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: markgross <markgross@thegnar.org>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>

ACPICA: Remove wakeup GPE reference counting which is not used

After the previous patch that introduced acpi_gpe_wakeup() and
modified the ACPI suspend and wakeup code to use it, the third
argument of acpi_{enable|disable}_gpe() and the GPE wakeup
reference counter are not necessary any more. Remove them and
modify all of the users of acpi_{enable|disable}_gpe()
accordingly. Also drop GPE type constants that aren't used
any more.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI / ACPI / PM: Platform support for PCI PME wake-up

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

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

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

Developed in cooperation with Matthew Garrett <mjg@redhat.com>.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI: replace acpi_integer by u64

acpi_integer is now obsolete and removed from the ACPICA code base,
replaced by u64.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI/PM: Propagate wake-up enable for PCIe devices too

Having read the PM part of the PCIe 2.0 specification more carefully
I think that it was a mistake to restrict the wake-up enable
propagation to non-PCIe devices, because if we do not request
control of the root ports' PME registers via OSC, PCIe PME is
supposed to be handled by the platform, just like the non-PCIe PME.
Even if we do that, the wake-up propagation is done to allow the
devices to wake up the system from sleep states which involves the
platform anyway, so it won't hurt.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: use pci_is_pcie() in pci core

Change for PCI core to use pci_is_pcie() instead of checking
pci_dev->is_pcie.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI / ACPI PM: Propagate wake-up enable for devices w/o ACPI support

Some PCI devices (not PCI Express), like PCI add-on cards, can
generate PME#, but they don't have any special platform wake-up
support. For this reason, even if they generate PME# to wake up the
system from a sleep state, wake-up events are not generated by the
platform.

It turns out that, at least on some systems, PCI bridges and the PCI
host bridge have ACPI GPEs associated with them that, if enabled to
generate wake-up events, allow the system to wake up if one of the
add-on devices asserts PME# while the system is in a sleep state.
Following this observation, if a PCI device without direct ACPI
wake-up support is prepared to wake up the system during a transition
into a sleep state (eg. suspend to RAM), try to configure the bridges
on the path from the device to the root bridge to wake-up the system.

Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI / ACPI PM: Rework some debug messages

Move a debug message from acpi_pci_sleep_wake() to
acpi_pm_device_sleep_wake() and use the standard dev_*() macros
in there.

Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI PM: Simplify PCI wake-up code

Rework the PCI wake-up code so that it's easier to read without
changing the functionality.

Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPICA: Update FADT flag definitions

Add new flags in the Boot Architecture flags field. Update comments
for all FADT flags. Add FADT version when each flag was defined.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI/ACPI: move _OSC code to pci_root.c

Move PCI _OSC management code from drivers/pci/pci-acpi.c to
drivers/acpi/pci_root.c. The benefits are

- We no longer need struct osc_data and its management code (contents
are moved to struct acpi_pci_root). This simplify the code, and we
no longer care about kmalloc() failure.

- We can make pci_acpi_osc_support() be a static function, which is
called only from drivers/acpi/pci_root.c.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Reviewed-by: Andrew Patterson <andrew.patterson@hp.com>
Tested-by: Andrew Patterson <andrew.patterson@hp.com>
Acked-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

pci-acpi: Cleanup _OSC evaluation code

Cleanup _OSC evaluation code. Some whitespace changes and a few other
minor cleanups.

Reviewed-by: Andrew Patterson <andrew.patterson@hp.com>
Tested-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI/ACPI: Remove unnecessary _OSC evaluation for control request

If a control had already been granted, we don't need to re-evaluate
_OSC for it because firmware may not reject control of any feature it
has previously granted control to.

Reviewed-by: Andrew Patterson <andrew.patterson@hp.com>
Tested-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: revert additional _OSC evaluation

Reverts adf411b819adc9fa96e9b3e638c7480d5e71d270.

The commit adf411b819adc9fa96e9b3e638c7480d5e71d270 was based on the
improper assumption that queried result was not updated when _OSC
support field was changed. But, in fact, queried result is updated
whenever _OSC support field was changed through __acpi_query_osc().
As a result, the commit adf411b819adc9fa96e9b3e638c7480d5e71d270 only
introduced unnecessary additional _OSC evaluation...

Tested-by: Andrew Patterson <andrew.patterson@hp.com>
Reviewed-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: remove obsolete _OSC capability support functions

The acpi_query_osc, __pci_osc_support_set, pci_osc_support_set, and
pcie_osc_support_set functions have been obsoleted in favor of setting
these capabilities during root bridge discovery with
pci_acpi_osc_support. There are no longer any callers of these
functions, so remove them.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: call _OSC support during root bridge discovery

Add pci_acpi_osc_support() and call it when a PCI bridge is added. This
allows us to avoid having every individual PCI root bridge driver call
_OSC support for every root bridge in their probe functions, a
significant savings in boot time.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: struct device - replace bus_id with dev_name(), dev_set_name()

This patch is part of a larger patch series which will remove
the "char bus_id[20]" name string from struct device. The device
name is managed in the kobject anyway, and without any size
limitation, and just needlessly copied into "struct device".

To set and read the device name dev_name(dev) and dev_set_name(dev)
must be used. If your code uses static kobjects, which it shouldn't
do, "const char *init_name" can be used to statically provide the
name the registered device should have. At registration time, the
init_name field is cleared, to enforce the use of dev_name(dev) to
access the device name at a later time.

We need to get rid of all occurrences of bus_id in the entire tree
to be able to enable the new interface. Please apply this patch,
and possibly convert any remaining remaining occurrences of bus_id.

Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-Off-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI: remove private acpica headers from driver files

External driver files should not include any private acpica headers.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI: ignore bit0 of _OSC return code

Currently acpi_run_osc() checks all the bits in _OSC result code (the
first DWORD in the capabilities buffer) to see error condition. But the
bit 0, which doesn't indicate any error, must be ignored.

The bit 0 is used as the query flag at _OSC invocation time. Some
platforms clear it during _OSC evaluation, but the others don't. On
latter platforms, current acpi_run_osc() mis-detects error when _OSC is
evaluated with query flag set because it doesn't ignore the bit 0.
Because of this, the __acpi_query_osc() always fails on such platforms.

And this is the cause of the problem that pci_osc_control_set() doesn't
work since the commit 4e39432f4df544d3dfe4fc90a22d87de64d15815 which
changed pci_osc_control_set() to use __acpi_query_osc().

Tested-by:"Tomasz Czernecki <czernecki@gmail.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI: Oops in ACPI with git latest

ACPI Warning (nseval-0168): Insufficient arguments - method [_OSC] needs 5, found 4 [20080926]
ACPI Warning (nspredef-0252): \_SB_.PCI0._OSC: Parameter count mismatch - ASL declared 5, expected 4 [20080926]
ACPI Error (nspredef-0163): \_SB_.PCI0._OSC: Missing expected return value [20080926]
BUG: unable to handle kernel NULL pointer dereference at 00000000
IP: [<c0237671>] acpi_run_osc+0xa1/0x170

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI/PCI: Fix return value of acpi_cuery_osc()

If acpi_query_osc() returns other than AE_OK, __pci_osc_support_set()
stops scanning ACPI objects to evaluate _OSC. This prevents subsequent
_OSCs from being evaluated if some of root bridge doesn't have _OSC, for
example. So acpi_query_osc() should return always AE_OK to evaluate all
_OSC.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: Always query _OSC control field in pci_osc_control_set()

In current pci_osc_control_set() implementation, once the _OSC control
field is queried, it is never queried again. But the query result can
change depending on the _OSC support field. For example, if PCI Express
Native Hot Plug control depends on ASPM support on a certain platform, a
PCI Express Native Hot Plug Control query would fail before the ASPM
driver was loaded, but it would succeed if the ASPM driver was loaded
first. Therefore, pci_osc_control_set() should query the _OSC control
field every time.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: Change pci_osc_control_set() to query control bits first

Current pci_osc_control_set() evaluates _OSC without query for control
bits, unless __pci_osc_support_set() is called beforehand. But as
strongly recommended in PCI firmware specification, it should query
control bits first.

This patch changes pci_osc_control_set() to query control bits first
even if __pci_osc_support_set() is not called beforehand.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: Fix possible race condition on _OSC evaluation

Fix possible race condition on _OSC evaluation.

Current _OSC evaluation code has possible race condition because it
maniputes osc_data linked list or its contents without any lock
mechanism.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: disable ASPM per ACPI FADT setting

The ACPI FADT table includes an ASPM control bit. If the bit is set, do
not enable ASPM since it may indicate that the platform doesn't actually
support the feature.

Tested-by: Jack Howarth <howarth@bromo.msbb.uc.edu>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI ACPI: Drop the second argument of platform_pci_choose_state

Since the second argument of acpi_pci_choose_state() and
platform_pci_choose_state() is never used, remove it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI PM: acpi_pm_device_sleep_state() cleanup

Get rid of a superfluous acpi_pm_device_sleep_state() parameter. The
only legitimate value of that parameter must be derived from the first
parameter, which is what all the callers already do. (However, this
does not address the fact that ACPI still doesn't set up those flags.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI ACPI: Rework PCI handling of wake-up

* Introduce function acpi_pm_device_sleep_wake() for enabling and
disabling the system wake-up capability of devices that are power
manageable by ACPI.

* Introduce function acpi_bus_can_wakeup() allowing other (dependent)
subsystems to check if ACPI is able to enable the system wake-up
capability of given device.

* Introduce callback .sleep_wake() in struct pci_platform_pm_ops and
for the ACPI PCI 'driver' make it use acpi_pm_device_sleep_wake().

* Introduce callback .can_wakeup() in struct pci_platform_pm_ops and
for the ACPI 'driver' make it use acpi_bus_can_wakeup().

* Move the PME# handlig code out of pci_enable_wake() and split it
into two functions, pci_pme_capable() and pci_pme_active(),
allowing the caller to check if given device is capable of
generating PME# from given power state and to enable/disable the
device's PME# functionality, respectively.

* Modify pci_enable_wake() to use the new ACPI callbacks and the new
PME#-related functions.

* Drop the generic .platform_enable_wakeup() callback that is not
used any more.

* Introduce device_set_wakeup_capable() that will set the
power.can_wakeup flag of given device.

* Rework PCI device PM initialization so that, if given device is
capable of generating wake-up events, either natively through the
PME# mechanism, or with the help of the platform, its
power.can_wakeup flag is set and its power.should_wakeup flag is
unset as appropriate.

* Make ACPI set the power.can_wakeup flag for devices found to be
wake-up capable by it.

* Make the ACPI wake-up code enable/disable GPEs for devices that
have the wakeup.flags.prepared flag set (which means that their
wake-up power has been enabled).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: rework pci_set_power_state function to call platform first

Rework pci_set_power_state() so that the platform callback is
invoked before the native mechanism, if necessary. Also, make
the function check if the device is power manageable by the
platform before invoking the platform callback.

This may matter if the device dependent on additional power
resources controlled by the platform is being put into D0, in which
case those power resources must be turned on before we attempt to
handle the device itself.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI: Introduce platform_pci_power_manageable function

Introduce function pointer platform_pci_power_manageable to be used
by the platform-related code to point to a function allowing us to
check if given device is power manageable by the platform.

Introduce acpi_pci_power_manageable() playing that role for ACPI.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Fix forcedeth hibernate/wake-on-lan problems

This patch is the minimal amount of code needed to support
wake-on-lan in platform mode properly (i.e. "ethtool -s eth0 wol g"
is sufficient, no additional magic needed) for me.

This is derived from David Brownells patch
(http://lists.laptop.org/pipermail/devel/2007-April/004691.html).
However I decided to move the hook into pci-acpi.c since the other
two pci hooks also live there and pci and acpi are the only users of
the platform_enable_wakeup-hook.

As a 'side-effect' this also makes wake on usb activity work for me
and I had to disable usb wakeup (which is enabled by default) using
the power/wakeup sysfs functionality ("echo disabled >
${sysfs_path_to_device}/power/wakeup").

(BTW I first thought the 'immediate reboot because of usb wake' effect is
caused by the optical mouse generating a wake event, but it rather
seems to be a problem with a flaky secondary usb host controller,
which sees a connected device where nothing is attached)

Signed-off-by: Tobias Diedrich <ranma+kernel@tdiedrich.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

PCI ACPI: Drop the second argument of platform_pci_choose_state

Since the second argument of acpi_pci_choose_state() and
platform_pci_choose_state() is never used, remove it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI PM: acpi_pm_device_sleep_state() cleanup

Get rid of a superfluous acpi_pm_device_sleep_state() parameter. The
only legitimate value of that parameter must be derived from the first
parameter, which is what all the callers already do. (However, this
does not address the fact that ACPI still doesn't set up those flags.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

pci-acpi: formatting cleanups for _OSC

Minor cleanup in pci-acpi.c.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

pci-acpi: remove unused variable in __pci_osc_support_set

The 'retval' variable in __pci_osc_support_set() is no longer
used. Remove this unused variable.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

pci-acpi: add flag to indicate query had been done

Current pci-acpi implementation checks osc_data->support_stat to see
if control bits had been already queried. It is not good from the
viewpoint of easy understanding. So this patch adds new 'is_queried'
flag to indicate query had been done.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

pci-acpi: use local buffer for _OSC

Current pci-acpi implementation uses array in osc_data directly to
evaluate _OSC. It needs to save the old data and restore it if _OSC
evaluation fails. To make it more robust, we should use local array to
evaluate _OSC.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

pci-acpi: remove duplicate code for _OSC

Remove the duplicated code in acpi_query_osc() and acpi_run_osc().
It simplifies the code very much.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Acked-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: another multiple _OSC memory leak fix

The acpi_query_osc() function can be called for the ACPI object that
doesn't have _OSC method. In this case, acpi_get_osc_data() would
allocate a useless memory region. To avoid this, we need to check the
existence of _OSC before calling acpi_get_osc_data() in acpi_query_osc().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: handle multiple _OSC

The pci_osc_control_set() function can be called for the ACPI object
that doesn't have _OSC method. In this case, acpi_get_osc_data() would
allocate a useless memory region. To avoid this, we need to check the
existence of _OSC before calling acpi_get_osc_data(). Here is a patch
to fix this problem in pci_osc_control_set.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI/PCI: handle multiple _OSC

There is an IA64 system here which have two pci root bridges with _OSC.
One _OSC disables SHPC control bit but the other not. Below patch makes
_OSC data per-device instead of one global, otherwise linux takes both
root bridges don't support SHPC.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

PCI ACPI: fix uninitialized variable in __pci_osc_support_set

Fix uninitialized variable in __pci_osc_support_set().

If the ACPI namespace doesn't have any device object corresponding to
the specified hid, 'retval' in __pci_osc_support_set() is not changed
by the acpi_query_osc() callback. Since 'retval' is not initizlized in
the current implementation, the contents of 'retval' is undefined in
this case. This causes a mis-handling of ctrlset_buf[OSC_SUPPORT_TYPE]
and will cause an unexpected result in the subsequent
pci_osc_control_set() call as a result.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

ACPI: acpi_pci_set_power_state() cleanups

Minor cleanups to acpi_pci_set_power_state(): use the ACPI and PCI
state symbols to make clear that a mapping is being done between PCI
and ACPI states, instead of using magic numbers. For paranoia's sake,
report any errors. Save five bytes (x86_64) too.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI: kernel-doc: fix pci-acpi warning

Fix PCI kernel-doc warning:
Warning(linux-2.6.24-git12//drivers/pci/pci-acpi.c:166): No description found for parameter 'hid'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

PCI ACPI: Fix comment describing acpi_pci_choose_state

The last line of the comment preceding the definition of
acpi_pci_choose_state() is incorrect. Remove it.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Len Brown <len.brown@intel.com>

kernel-doc: fix pci-acpi warning

Fix PCI kernel-doc warning:
Warning(linux-2.6.24-git12//drivers/pci/pci-acpi.c:166): No description found for parameter 'hid'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI ACPI: Added a function to register _OSC with only PCIe devices.

The function pci_osc_support_set() traverses every root bridge when
checking for _OSC support for a capability. It quits as soon as it finds a
device/bridge that doesn't support the requested capability. This won't
work for systems that have mixed PCI and PCIe bridges when checking for
PCIe features. I split this function into two -- pci_osc_support_set() and
pcie_osc_support_set(). The latter is used when only PCIe devices should be
traversed.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

PCI: drivers/pci/: remove unused exports

This patch removes the following unused exports:
- remove the following unused EXPORT_SYMBOL's:
- pci-acpi.c: pci_osc_support_set
- proc.c: pci_proc_detach_bus
- remove the following unused EXPORT_SYMBOL_GPL's:
- bus.c: pci_walk_bus
- probe.c: pci_create_bus
- setup-res.c: pci_claim_resource

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

ACPI: restore CONFIG_ACPI_SLEEP

Restore the 2.6.22 CONFIG_ACPI_SLEEP build option, but now shadowing the
new CONFIG_PM_SLEEP option.

Signed-off-by: Len Brown <len.brown@intel.com>
[ Modified to work with the PM config setup changes. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ACPI: ignore _PSx method for hotplugable PCI devices

If the ACPI device has _EJ0, ignore the device.
_PSx will set power for the slot,
and the hotplug driver will take care of _PSx.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

ACPI: Use ACPI methods to select PCI device suspend state

applied after Rafel's 'PM: Update global suspend and hibernation
operations framework' patch set

Signed-off-by: Shaohua Li<shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

PCI: fix AER driver error information

Below patch fixes aer driver error information and enables aer driver
although CONFIG_ACPI=n.

As a matter of fact, the new patch is created from below 2 patches plus
a minor patch apply fuzz fixing. Because the second patch fixed a compilation
error introduced by the first patch, I merge them to facilitate bisect.


1) http://marc.info/?l=linux-kernel&m=117783233918191&w=2;
2) http://marc.info/?l=linux-mm-commits&m=118046936720790&w=2


Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

ACPI: Disable MSI on request of FADT

The ACPI spec defines the bit and Microsoft uses it,
so Linux must use it too.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

pci: clear osc support flags if no _OSC method

So it looks like pci aer code will call pci_osc_support_set to tell the
firmware about OSC_EXT_PCI_CONFIG_SUPPORT flag. that causes
ctrlset_buf[OSC_SUPPORT_TYPE] to evaluate to true when pciehp calls
pci_osc_control_set() is called (to attempt to use OSC to gain native
pcie control from firmware), regardless of whether or not _OSC was
actually successfully executed. That causes this section of code:
if (ctrlset_buf[OSC_SUPPORT_TYPE] &&
((global_ctrlsets & ctrlset) != ctrlset)) {
return AE_SUPPORT;
}
to be hit.

This patch will reset the OSC_SUPPORT_TYPE field if _OSC fails, and then
would allow pciehp to go ahead and try to run _OSC again.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] PCI ACPI: Rename the functions to avoid multiple instances.

There were two instances of pci_acpi_init(), one in
drivers/pci/pci-acpi.c and another in arch/i386/pci/acpi.c.
Rename the one in pci-acpi.c and make it consistent with
other names in the same file.

Signed-off-by: Muthukumar R <muthur@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[PATCH] pci: correctly allocate return buffers for osc calls

The OSC set and query functions do not allocate enough space for return
values, and set the output buffer length to a false, too large value. This
causes the acpi-ca code to assume that the output buffer is larger than it
actually is, and overwrite memory when copying acpi return buffers into
this caller provided buffer. In some cases this can cause kernel oops if
the memory that is overwritten is a pointer. This patch will change these
calls to use a dynamically allocated output buffer, thus allowing the
acpi-ca code to decide how much space is needed.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: "Yu, Luming" <luming.yu@intel.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] PCI: kernel-doc fix for pci-acpi.c

Fix kernel-doc warning in pci/pci-acpi.c.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] pciehp: request control of each hotplug controller individually

This patch tweaks the way pciehp requests control of the hotplug
hardware from BIOS. It now tries to invoke the ACPI _OSC method
for a specific hotplug controller only, rather than walking the
entire acpi namespace invoking all possible _OSC methods under
all host bridges. This allows us to gain control of each hotplug
controller individually, even if BIOS fails to give us control of
some other hotplug controller in the system.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

[ACPI] gut acpi_pci_choose_state() to avoid conflict
with pending pm_message_t re-definition.

Signed-off-by: Len Brown <len.brown@intel.com>

[ACPI] pci_set_power_state() now calls
platform_pci_set_power_state()
and ACPI can answer

http://bugzilla.kernel.org/show_bug.cgi?id=4277

Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

[ACPI] PCI can now get suspend state from firmware

pci_choose_state() can now call
platform_pci_choose_state()
and ACPI can answer

http://bugzilla.kernel.org/show_bug.cgi?id=4277

Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

[ACPI] Bind ACPI and PCI devices

http://bugzilla.kernel.org/show_bug.cgi?id=4277

Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

[PATCH] PCI: Clean up a lot of sparse "Should it be static?" warnings.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!