2009-02-24 05:50:35 +00:00
|
|
|
What: /sys/bus/pci/drivers/.../bind
|
|
|
|
|
Date: December 2003
|
|
|
|
|
Contact: linux-pci@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
Writing a device location to this file will cause
|
|
|
|
|
the driver to attempt to bind to the device found at
|
|
|
|
|
this location. This is useful for overriding default
|
|
|
|
|
bindings. The format for the location is: DDDD:BB:DD.F.
|
|
|
|
|
That is Domain:Bus:Device.Function and is the same as
|
|
|
|
|
found in /sys/bus/pci/devices/. For example:
|
|
|
|
|
# echo 0000:00:19.0 > /sys/bus/pci/drivers/foo/bind
|
|
|
|
|
(Note: kernels before 2.6.28 may require echo -n).
|
|
|
|
|
|
|
|
|
|
What: /sys/bus/pci/drivers/.../unbind
|
|
|
|
|
Date: December 2003
|
|
|
|
|
Contact: linux-pci@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
Writing a device location to this file will cause the
|
|
|
|
|
driver to attempt to unbind from the device found at
|
|
|
|
|
this location. This may be useful when overriding default
|
|
|
|
|
bindings. The format for the location is: DDDD:BB:DD.F.
|
|
|
|
|
That is Domain:Bus:Device.Function and is the same as
|
|
|
|
|
found in /sys/bus/pci/devices/. For example:
|
|
|
|
|
# echo 0000:00:19.0 > /sys/bus/pci/drivers/foo/unbind
|
|
|
|
|
(Note: kernels before 2.6.28 may require echo -n).
|
|
|
|
|
|
|
|
|
|
What: /sys/bus/pci/drivers/.../new_id
|
|
|
|
|
Date: December 2003
|
|
|
|
|
Contact: linux-pci@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
Writing a device ID to this file will attempt to
|
|
|
|
|
dynamically add a new device ID to a PCI device driver.
|
|
|
|
|
This may allow the driver to support more hardware than
|
|
|
|
|
was included in the driver's static device ID support
|
|
|
|
|
table at compile time. The format for the device ID is:
|
|
|
|
|
VVVV DDDD SVVV SDDD CCCC MMMM PPPP. That is Vendor ID,
|
|
|
|
|
Device ID, Subsystem Vendor ID, Subsystem Device ID,
|
|
|
|
|
Class, Class Mask, and Private Driver Data. The Vendor ID
|
|
|
|
|
and Device ID fields are required, the rest are optional.
|
|
|
|
|
Upon successfully adding an ID, the driver will probe
|
|
|
|
|
for the device and attempt to bind to it. For example:
|
|
|
|
|
# echo "8086 10f5" > /sys/bus/pci/drivers/foo/new_id
|
|
|
|
|
|
2009-02-24 05:52:23 +00:00
|
|
|
What: /sys/bus/pci/drivers/.../remove_id
|
|
|
|
|
Date: February 2009
|
|
|
|
|
Contact: Chris Wright <chrisw@sous-sol.org>
|
|
|
|
|
Description:
|
|
|
|
|
Writing a device ID to this file will remove an ID
|
|
|
|
|
that was dynamically added via the new_id sysfs entry.
|
|
|
|
|
The format for the device ID is:
|
|
|
|
|
VVVV DDDD SVVV SDDD CCCC MMMM. That is Vendor ID, Device
|
|
|
|
|
ID, Subsystem Vendor ID, Subsystem Device ID, Class,
|
|
|
|
|
and Class Mask. The Vendor ID and Device ID fields are
|
|
|
|
|
required, the rest are optional. After successfully
|
|
|
|
|
removing an ID, the driver will no longer support the
|
|
|
|
|
device. This is useful to ensure auto probing won't
|
|
|
|
|
match the driver to the device. For example:
|
|
|
|
|
# echo "8086 10f5" > /sys/bus/pci/drivers/foo/remove_id
|
|
|
|
|
|
2009-03-20 20:56:31 +00:00
|
|
|
What: /sys/bus/pci/rescan
|
|
|
|
|
Date: January 2009
|
|
|
|
|
Contact: Linux PCI developers <linux-pci@vger.kernel.org>
|
|
|
|
|
Description:
|
|
|
|
|
Writing a non-zero value to this attribute will
|
|
|
|
|
force a rescan of all PCI buses in the system, and
|
|
|
|
|
re-discover previously removed devices.
|
|
|
|
|
|
2011-10-06 18:08:18 +00:00
|
|
|
What: /sys/bus/pci/devices/.../msi_irqs/
|
|
|
|
|
Date: September, 2011
|
|
|
|
|
Contact: Neil Horman <nhorman@tuxdriver.com>
|
|
|
|
|
Description:
|
|
|
|
|
The /sys/devices/.../msi_irqs directory contains a variable set
|
2013-12-19 20:30:17 +00:00
|
|
|
of files, with each file being named after a corresponding msi
|
|
|
|
|
irq vector allocated to that device.
|
2011-10-06 18:08:18 +00:00
|
|
|
|
2013-12-19 20:30:17 +00:00
|
|
|
What: /sys/bus/pci/devices/.../msi_irqs/<N>
|
2011-10-06 18:08:18 +00:00
|
|
|
Date: September 2011
|
|
|
|
|
Contact: Neil Horman <nhorman@tuxdriver.com>
|
|
|
|
|
Description:
|
|
|
|
|
This attribute indicates the mode that the irq vector named by
|
2013-12-19 20:30:17 +00:00
|
|
|
the file is in (msi vs. msix)
|
2011-10-06 18:08:18 +00:00
|
|
|
|
2009-03-20 20:56:36 +00:00
|
|
|
What: /sys/bus/pci/devices/.../remove
|
|
|
|
|
Date: January 2009
|
|
|
|
|
Contact: Linux PCI developers <linux-pci@vger.kernel.org>
|
|
|
|
|
Description:
|
|
|
|
|
Writing a non-zero value to this attribute will
|
|
|
|
|
hot-remove the PCI device and any of its children.
|
|
|
|
|
|
2011-05-13 00:11:39 +00:00
|
|
|
What: /sys/bus/pci/devices/.../pci_bus/.../rescan
|
|
|
|
|
Date: May 2011
|
|
|
|
|
Contact: Linux PCI developers <linux-pci@vger.kernel.org>
|
|
|
|
|
Description:
|
|
|
|
|
Writing a non-zero value to this attribute will
|
|
|
|
|
force a rescan of the bus and all child buses,
|
|
|
|
|
and re-discover devices removed earlier from this
|
2013-05-21 03:49:35 +00:00
|
|
|
part of the device tree.
|
2011-05-13 00:11:39 +00:00
|
|
|
|
2009-03-20 20:56:41 +00:00
|
|
|
What: /sys/bus/pci/devices/.../rescan
|
|
|
|
|
Date: January 2009
|
|
|
|
|
Contact: Linux PCI developers <linux-pci@vger.kernel.org>
|
|
|
|
|
Description:
|
|
|
|
|
Writing a non-zero value to this attribute will
|
|
|
|
|
force a rescan of the device's parent bus and all
|
|
|
|
|
child buses, and re-discover devices removed earlier
|
|
|
|
|
from this part of the device tree.
|
|
|
|
|
|
2009-07-27 20:37:48 +00:00
|
|
|
What: /sys/bus/pci/devices/.../reset
|
|
|
|
|
Date: July 2009
|
|
|
|
|
Contact: Michael S. Tsirkin <mst@redhat.com>
|
|
|
|
|
Description:
|
|
|
|
|
Some devices allow an individual function to be reset
|
|
|
|
|
without affecting other functions in the same device.
|
|
|
|
|
For devices that have this support, a file named reset
|
|
|
|
|
will be present in sysfs. Writing 1 to this file
|
|
|
|
|
will perform reset.
|
|
|
|
|
|
2008-03-05 16:52:39 +00:00
|
|
|
What: /sys/bus/pci/devices/.../vpd
|
|
|
|
|
Date: February 2008
|
|
|
|
|
Contact: Ben Hutchings <bhutchings@solarflare.com>
|
|
|
|
|
Description:
|
|
|
|
|
A file named vpd in a device directory will be a
|
|
|
|
|
binary file containing the Vital Product Data for the
|
|
|
|
|
device. It should follow the VPD format defined in
|
|
|
|
|
PCI Specification 2.1 or 2.2, but users should consider
|
|
|
|
|
that some devices may have malformatted data. If the
|
|
|
|
|
underlying VPD has a writable section then the
|
|
|
|
|
corresponding section of this file will be writable.
|
2009-03-20 03:25:17 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../virtfnN
|
|
|
|
|
Date: March 2009
|
|
|
|
|
Contact: Yu Zhao <yu.zhao@intel.com>
|
|
|
|
|
Description:
|
|
|
|
|
This symbolic link appears when hardware supports the SR-IOV
|
|
|
|
|
capability and the Physical Function driver has enabled it.
|
|
|
|
|
The symbolic link points to the PCI device sysfs entry of the
|
|
|
|
|
Virtual Function whose index is N (0...MaxVFs-1).
|
|
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../dep_link
|
|
|
|
|
Date: March 2009
|
|
|
|
|
Contact: Yu Zhao <yu.zhao@intel.com>
|
|
|
|
|
Description:
|
|
|
|
|
This symbolic link appears when hardware supports the SR-IOV
|
|
|
|
|
capability and the Physical Function driver has enabled it,
|
|
|
|
|
and this device has vendor specific dependencies with others.
|
|
|
|
|
The symbolic link points to the PCI device sysfs entry of
|
|
|
|
|
Physical Function this device depends on.
|
|
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../physfn
|
|
|
|
|
Date: March 2009
|
|
|
|
|
Contact: Yu Zhao <yu.zhao@intel.com>
|
|
|
|
|
Description:
|
|
|
|
|
This symbolic link appears when a device is a Virtual Function.
|
|
|
|
|
The symbolic link points to the PCI device sysfs entry of the
|
|
|
|
|
Physical Function this device associates with.
|
2009-06-16 02:01:25 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/slots/.../module
|
|
|
|
|
Date: June 2009
|
|
|
|
|
Contact: linux-pci@vger.kernel.org
|
|
|
|
|
Description:
|
|
|
|
|
This symbolic link points to the PCI hotplug controller driver
|
|
|
|
|
module that manages the hotplug slot.
|
2010-07-26 10:56:50 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../label
|
|
|
|
|
Date: July 2010
|
|
|
|
|
Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
|
|
|
|
|
Description:
|
|
|
|
|
Reading this attribute will provide the firmware
|
2011-03-02 17:04:17 +00:00
|
|
|
given name (SMBIOS type 41 string or ACPI _DSM string) of
|
|
|
|
|
the PCI device. The attribute will be created only
|
|
|
|
|
if the firmware has given a name to the PCI device.
|
|
|
|
|
ACPI _DSM string name will be given priority if the
|
|
|
|
|
system firmware provides SMBIOS type 41 string also.
|
2010-07-26 10:56:50 +00:00
|
|
|
Users:
|
|
|
|
|
Userspace applications interested in knowing the
|
|
|
|
|
firmware assigned name of the PCI device.
|
|
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../index
|
|
|
|
|
Date: July 2010
|
|
|
|
|
Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
|
|
|
|
|
Description:
|
|
|
|
|
Reading this attribute will provide the firmware
|
2011-03-02 17:04:17 +00:00
|
|
|
given instance (SMBIOS type 41 device type instance) of the
|
|
|
|
|
PCI device. The attribute will be created only if the firmware
|
|
|
|
|
has given an instance number to the PCI device.
|
2010-07-26 10:56:50 +00:00
|
|
|
Users:
|
|
|
|
|
Userspace applications interested in knowing the
|
|
|
|
|
firmware assigned device type instance of the PCI
|
|
|
|
|
device that can help in understanding the firmware
|
|
|
|
|
intended order of the PCI device.
|
2011-03-02 17:04:17 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../acpi_index
|
|
|
|
|
Date: July 2010
|
|
|
|
|
Contact: Narendra K <narendra_k@dell.com>, linux-bugs@dell.com
|
|
|
|
|
Description:
|
|
|
|
|
Reading this attribute will provide the firmware
|
|
|
|
|
given instance (ACPI _DSM instance number) of the PCI device.
|
|
|
|
|
The attribute will be created only if the firmware has given
|
|
|
|
|
an instance number to the PCI device. ACPI _DSM instance number
|
|
|
|
|
will be given priority if the system firmware provides SMBIOS
|
|
|
|
|
type 41 device type instance also.
|
|
|
|
|
Users:
|
|
|
|
|
Userspace applications interested in knowing the
|
|
|
|
|
firmware assigned instance number of the PCI
|
|
|
|
|
device that can help in understanding the firmware
|
|
|
|
|
intended order of the PCI device.
|
2012-08-08 01:07:41 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../d3cold_allowed
|
|
|
|
|
Date: July 2012
|
|
|
|
|
Contact: Huang Ying <ying.huang@intel.com>
|
|
|
|
|
Description:
|
|
|
|
|
d3cold_allowed is bit to control whether the corresponding PCI
|
|
|
|
|
device can be put into D3Cold state. If it is cleared, the
|
|
|
|
|
device will never be put into D3Cold state. If it is set, the
|
|
|
|
|
device may be put into D3Cold state if other requirements are
|
|
|
|
|
satisfied too. Reading this attribute will show the current
|
|
|
|
|
value of d3cold_allowed bit. Writing this attribute will set
|
|
|
|
|
the value of d3cold_allowed bit.
|
2012-11-28 03:31:37 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../sriov_totalvfs
|
|
|
|
|
Date: November 2012
|
|
|
|
|
Contact: Donald Dutile <ddutile@redhat.com>
|
|
|
|
|
Description:
|
|
|
|
|
This file appears when a physical PCIe device supports SR-IOV.
|
|
|
|
|
Userspace applications can read this file to determine the
|
|
|
|
|
maximum number of Virtual Functions (VFs) a PCIe physical
|
|
|
|
|
function (PF) can support. Typically, this is the value reported
|
|
|
|
|
in the PF's SR-IOV extended capability structure's TotalVFs
|
|
|
|
|
element. Drivers have the ability at probe time to reduce the
|
|
|
|
|
value read from this file via the pci_sriov_set_totalvfs()
|
|
|
|
|
function.
|
|
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../sriov_numvfs
|
|
|
|
|
Date: November 2012
|
|
|
|
|
Contact: Donald Dutile <ddutile@redhat.com>
|
|
|
|
|
Description:
|
|
|
|
|
This file appears when a physical PCIe device supports SR-IOV.
|
|
|
|
|
Userspace applications can read and write to this file to
|
|
|
|
|
determine and control the enablement or disablement of Virtual
|
|
|
|
|
Functions (VFs) on the physical function (PF). A read of this
|
|
|
|
|
file will return the number of VFs that are enabled on this PF.
|
|
|
|
|
A number written to this file will enable the specified
|
|
|
|
|
number of VFs. A userspace application would typically read the
|
|
|
|
|
file and check that the value is zero, and then write the number
|
|
|
|
|
of VFs that should be enabled on the PF; the value written
|
|
|
|
|
should be less than or equal to the value in the sriov_totalvfs
|
|
|
|
|
file. A userspace application wanting to disable the VFs would
|
|
|
|
|
write a zero to this file. The core ensures that valid values
|
|
|
|
|
are written to this file, and returns errors when values are not
|
|
|
|
|
valid. For example, writing a 2 to this file when sriov_numvfs
|
|
|
|
|
is not 0 and not 2 already will return an error. Writing a 10
|
|
|
|
|
when the value of sriov_totalvfs is 8 will return an error.
|
PCI: Introduce new device binding path using pci_dev.driver_override
The driver_override field allows us to specify the driver for a device
rather than relying on the driver to provide a positive match of the
device. This shortcuts the existing process of looking up the vendor and
device ID, adding them to the driver new_id, binding the device, then
removing the ID, but it also provides a couple advantages.
First, the above existing process allows the driver to bind to any device
matching the new_id for the window where it's enabled. This is often not
desired, such as the case of trying to bind a single device to a meta
driver like pci-stub or vfio-pci. Using driver_override we can do this
deterministically using:
echo pci-stub > /sys/bus/pci/devices/0000:03:00.0/driver_override
echo 0000:03:00.0 > /sys/bus/pci/devices/0000:03:00.0/driver/unbind
echo 0000:03:00.0 > /sys/bus/pci/drivers_probe
Previously we could not invoke drivers_probe after adding a device to
new_id for a driver as we get non-deterministic behavior whether the driver
we intend or the standard driver will claim the device. Now it becomes a
deterministic process, only the driver matching driver_override will probe
the device.
To return the device to the standard driver, we simply clear the
driver_override and reprobe the device:
echo > /sys/bus/pci/devices/0000:03:00.0/driver_override
echo 0000:03:00.0 > /sys/bus/pci/devices/0000:03:00.0/driver/unbind
echo 0000:03:00.0 > /sys/bus/pci/drivers_probe
Another advantage to this approach is that we can specify a driver override
to force a specific binding or prevent any binding. For instance when an
IOMMU group is exposed to userspace through VFIO we require that all
devices within that group are owned by VFIO. However, devices can be
hot-added into an IOMMU group, in which case we want to prevent the device
from binding to any driver (override driver = "none") or perhaps have it
automatically bind to vfio-pci. With driver_override it's a simple matter
for this field to be set internally when the device is first discovered to
prevent driver matches.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-20 14:53:21 +00:00
|
|
|
|
|
|
|
|
What: /sys/bus/pci/devices/.../driver_override
|
|
|
|
|
Date: April 2014
|
|
|
|
|
Contact: Alex Williamson <alex.williamson@redhat.com>
|
|
|
|
|
Description:
|
|
|
|
|
This file allows the driver for a device to be specified which
|
|
|
|
|
will override standard static and dynamic ID matching. When
|
|
|
|
|
specified, only a driver with a name matching the value written
|
|
|
|
|
to driver_override will have an opportunity to bind to the
|
|
|
|
|
device. The override is specified by writing a string to the
|
|
|
|
|
driver_override file (echo pci-stub > driver_override) and
|
|
|
|
|
may be cleared with an empty string (echo > driver_override).
|
|
|
|
|
This returns the device to standard matching rules binding.
|
|
|
|
|
Writing to driver_override does not automatically unbind the
|
|
|
|
|
device from its current driver or make any attempt to
|
|
|
|
|
automatically load the specified driver. If no driver with a
|
|
|
|
|
matching name is currently loaded in the kernel, the device
|
|
|
|
|
will not bind to any driver. This also allows devices to
|
|
|
|
|
opt-out of driver binding using a driver_override name such as
|
|
|
|
|
"none". Only a single driver may be specified in the override,
|
|
|
|
|
there is no support for parsing delimiters.
|
