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+What: /sys/bus/pci/drivers/.../bind
+What: /sys/devices/pciX/.../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
+What: /sys/devices/pciX/.../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
+What: /sys/devices/pciX/.../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
+
+What: /sys/bus/pci/drivers/.../remove_id
+What: /sys/devices/pciX/.../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
+
+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.
+
+What: /sys/bus/pci/devices/.../msi_bus
+Date: September 2014
+Contact: Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+ Writing a zero value to this attribute disallows MSI and
+ MSI-X for any future drivers of the device. If the device
+ is a bridge, MSI and MSI-X will be disallowed for future
+ drivers of all child devices under the bridge. Drivers
+ must be reloaded for the new setting to take effect.
+
+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
+ of files, with each file being named after a corresponding msi
+ irq vector allocated to that device.
+
+What: /sys/bus/pci/devices/.../msi_irqs/<N>
+Date: September 2011
+Contact: Neil Horman <nhorman@tuxdriver.com>
+Description:
+ This attribute indicates the mode that the irq vector named by
+ the file is in (msi vs. msix)
+
+What: /sys/bus/pci/devices/.../irq
+Date: August 2021
+Contact: Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+ If a driver has enabled MSI (not MSI-X), "irq" contains the
+ IRQ of the first MSI vector. Otherwise "irq" contains the
+ IRQ of the legacy INTx interrupt.
+
+ "irq" being set to 0 indicates that the device isn't
+ capable of generating legacy INTx interrupts.
+
+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.
+
+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
+ part of the device tree.
+
+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.
+
+What: /sys/bus/pci/devices/.../reset_method
+Date: August 2021
+Contact: Amey Narkhede <ameynarkhede03@gmail.com>
+Description:
+ Some devices allow an individual function to be reset
+ without affecting other functions in the same slot.
+
+ For devices that have this support, a file named
+ reset_method is present in sysfs. Reading this file
+ gives names of the supported and enabled reset methods and
+ their ordering. Writing a space-separated list of names of
+ reset methods sets the reset methods and ordering to be
+ used when resetting the device. Writing an empty string
+ disables the ability to reset the device. Writing
+ "default" enables all supported reset methods in the
+ default ordering.
+
+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.
+
+What: /sys/bus/pci/devices/.../vpd
+Date: February 2008
+Contact: Ben Hutchings <bwh@kernel.org>
+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 incorrectly formatted data.
+ If the underlying VPD has a writable section then the
+ corresponding section of this file will be writable.
+
+What: /sys/bus/pci/devices/.../virtfn<N>
+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.
+
+What: /sys/bus/pci/devices/.../modalias
+Date: May 2005
+Contact: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Description:
+ This attribute indicates the PCI ID of the device object.
+
+ That is in the format:
+ pci:vXXXXXXXXdXXXXXXXXsvXXXXXXXXsdXXXXXXXXbcXXscXXiXX,
+ where:
+
+ - vXXXXXXXX contains the vendor ID;
+ - dXXXXXXXX contains the device ID;
+ - svXXXXXXXX contains the sub-vendor ID;
+ - sdXXXXXXXX contains the subsystem device ID;
+ - bcXX contains the device class;
+ - scXX contains the device subclass;
+ - iXX contains the device class programming interface.
+
+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.
+
+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
+ 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.
+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 given instance
+ number of the PCI device. Depending on the platform this can
+ be for example the SMBIOS type 41 device type instance or the
+ user-defined ID (UID) on s390. The attribute will be created
+ only if the firmware has given an instance number to the PCI
+ device and that number is guaranteed to uniquely identify the
+ device in the system.
+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.
+
+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.
+
+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.
+
+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.
+
+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.
+
+What: /sys/bus/pci/devices/.../numa_node
+Date: Oct 2014
+Contact: Prarit Bhargava <prarit@redhat.com>
+Description:
+ This file contains the NUMA node to which the PCI device is
+ attached, or -1 if the node is unknown. The initial value
+ comes from an ACPI _PXM method or a similar firmware
+ source. If that is missing or incorrect, this file can be
+ written to override the node. In that case, please report
+ a firmware bug to the system vendor. Writing to this file
+ taints the kernel with TAINT_FIRMWARE_WORKAROUND, which
+ reduces the supportability of your system.
+
+What: /sys/bus/pci/devices/.../revision
+Date: November 2016
+Contact: Emil Velikov <emil.l.velikov@gmail.com>
+Description:
+ This file contains the revision field of the PCI device.
+ The value comes from device config space. The file is read only.
+
+What: /sys/bus/pci/devices/.../sriov_drivers_autoprobe
+Date: April 2017
+Contact: Bodong Wang<bodong@mellanox.com>
+Description:
+ This file is associated with the PF of a device that
+ supports SR-IOV. It determines whether newly-enabled VFs
+ are immediately bound to a driver. It initially contains
+ 1, which means the kernel automatically binds VFs to a
+ compatible driver immediately after they are enabled. If
+ an application writes 0 to the file before enabling VFs,
+ the kernel will not bind VFs to a driver.
+
+ A typical use case is to write 0 to this file, then enable
+ VFs, then assign the newly-created VFs to virtual machines.
+ Note that changing this file does not affect already-
+ enabled VFs. In this scenario, the user must first disable
+ the VFs, write 0 to sriov_drivers_autoprobe, then re-enable
+ the VFs.
+
+ This is similar to /sys/bus/pci/drivers_autoprobe, but
+ affects only the VFs associated with a specific PF.
+
+What: /sys/bus/pci/devices/.../p2pmem/size
+Date: November 2017
+Contact: Logan Gunthorpe <logang@deltatee.com>
+Description:
+ If the device has any Peer-to-Peer memory registered, this
+ file contains the total amount of memory that the device
+ provides (in decimal).
+
+What: /sys/bus/pci/devices/.../p2pmem/available
+Date: November 2017
+Contact: Logan Gunthorpe <logang@deltatee.com>
+Description:
+ If the device has any Peer-to-Peer memory registered, this
+ file contains the amount of memory that has not been
+ allocated (in decimal).
+
+What: /sys/bus/pci/devices/.../p2pmem/published
+Date: November 2017
+Contact: Logan Gunthorpe <logang@deltatee.com>
+Description:
+ If the device has any Peer-to-Peer memory registered, this
+ file contains a '1' if the memory has been published for
+ use outside the driver that owns the device.
+
+What: /sys/bus/pci/devices/.../p2pmem/allocate
+Date: August 2022
+Contact: Logan Gunthorpe <logang@deltatee.com>
+Description:
+ This file allows mapping p2pmem into userspace. For each
+ mmap() call on this file, the kernel will allocate a chunk
+ of Peer-to-Peer memory for use in Peer-to-Peer transactions.
+ This memory can be used in O_DIRECT calls to NVMe backed
+ files for Peer-to-Peer copies.
+
+What: /sys/bus/pci/devices/.../link/clkpm
+ /sys/bus/pci/devices/.../link/l0s_aspm
+ /sys/bus/pci/devices/.../link/l1_aspm
+ /sys/bus/pci/devices/.../link/l1_1_aspm
+ /sys/bus/pci/devices/.../link/l1_2_aspm
+ /sys/bus/pci/devices/.../link/l1_1_pcipm
+ /sys/bus/pci/devices/.../link/l1_2_pcipm
+Date: October 2019
+Contact: Heiner Kallweit <hkallweit1@gmail.com>
+Description: If ASPM is supported for an endpoint, these files can be
+ used to disable or enable the individual power management
+ states. Write y/1/on to enable, n/0/off to disable.
+
+What: /sys/bus/pci/devices/.../power_state
+Date: November 2020
+Contact: Linux PCI developers <linux-pci@vger.kernel.org>
+Description:
+ This file contains the current PCI power state of the device.
+ The value comes from the PCI kernel device state and can be one
+ of: "unknown", "error", "D0", D1", "D2", "D3hot", "D3cold".
+ The file is read only.
+
+What: /sys/bus/pci/devices/.../sriov_vf_total_msix
+Date: January 2021
+Contact: Leon Romanovsky <leonro@nvidia.com>
+Description:
+ This file is associated with a SR-IOV physical function (PF).
+ It contains the total number of MSI-X vectors available for
+ assignment to all virtual functions (VFs) associated with PF.
+ The value will be zero if the device doesn't support this
+ functionality. For supported devices, the value will be
+ constant and won't be changed after MSI-X vectors assignment.
+
+What: /sys/bus/pci/devices/.../sriov_vf_msix_count
+Date: January 2021
+Contact: Leon Romanovsky <leonro@nvidia.com>
+Description:
+ This file is associated with a SR-IOV virtual function (VF).
+ It allows configuration of the number of MSI-X vectors for
+ the VF. This allows devices that have a global pool of MSI-X
+ vectors to optimally divide them between VFs based on VF usage.
+
+ The values accepted are:
+ * > 0 - this number will be reported as the Table Size in the
+ VF's MSI-X capability
+ * < 0 - not valid
+ * = 0 - will reset to the device default value
+
+ The file is writable if the PF is bound to a driver that
+ implements ->sriov_set_msix_vec_count().
+
+What: /sys/bus/pci/devices/.../resourceN_resize
+Date: September 2022
+Contact: Alex Williamson <alex.williamson@redhat.com>
+Description:
+ These files provide an interface to PCIe Resizable BAR support.
+ A file is created for each BAR resource (N) supported by the
+ PCIe Resizable BAR extended capability of the device. Reading
+ each file exposes the bitmap of available resource sizes:
+
+ # cat resource1_resize
+ 00000000000001c0
+
+ The bitmap represents supported resource sizes for the BAR,
+ where bit0 = 1MB, bit1 = 2MB, bit2 = 4MB, etc. In the above
+ example the device supports 64MB, 128MB, and 256MB BAR sizes.
+
+ When writing the file, the user provides the bit position of
+ the desired resource size, for example:
+
+ # echo 7 > resource1_resize
+
+ This indicates to set the size value corresponding to bit 7,
+ 128MB. The resulting size is 2 ^ (bit# + 20). This definition
+ matches the PCIe specification of this capability.
+
+ In order to make use of resource resizing, all PCI drivers must
+ be unbound from the device and peer devices under the same
+ parent bridge may need to be soft removed. In the case of
+ VGA devices, writing a resize value will remove low level
+ console drivers from the device. Raw users of pci-sysfs
+ resourceN attributes must be terminated prior to resizing.
+ Success of the resizing operation is not guaranteed.