IAVF(4)                FreeBSD Kernel Interfaces Manual                IAVF(4)

NAME
     iavf - Intel Adaptive Virtual Function driver

SYNOPSIS
     To compile this driver into the kernel, place the following lines in your
     kernel configuration file:

           device iflib
           device iavf

     To load the driver as a module at boot time, place the following lines in
     loader.conf(5):

           if_iavf_load="YES"

DESCRIPTION
     The iavf driver provides support for the PCI Virtual Functions from the
     700 Series of ethernet devices and newer product families.  The driver
     supports Jumbo Frames, TX/RX checksum offload, TCP segmentation offload
     (TSO), Large Receive Offload (LRO), VLAN tag insertion/extraction, VLAN
     checksum offload, VLAN TSO, and Receive Side Steering (RSS), all for both
     IPv4 and IPv6.  For further hardware information and questions related to
     hardware requirements, see http://support.intel.com/.

     Support for Jumbo Frames is provided via the interface MTU setting.
     Selecting an MTU larger than 1500 bytes with the ifconfig(8) utility
     configures the adapter to receive and transmit Jumbo Frames.  The maximum
     MTU size for Jumbo Frames is 9706.

     Offloads are also controlled via the interface, for instance,
     checksumming for both IPv4 and IPv6 can be set and unset, TSO4 and/or
     TSO6, and finally LRO can be set and unset.

     For more information on configuring this device, see ifconfig(8).

     NOTE: This iavf driver is only for Virtual Functions.  For 700 series
     Physical Functions, use the ixl(4) driver.

LOADER TUNABLES
     Tunables can be set at the loader(8) prompt before booting the kernel or
     stored in loader.conf(5).

     hw.iavf.rx_itr
             The RX interrupt rate value, set to 62 (124 usec) by default.

     hw.iavf.tx_itr
             The TX interrupt rate value, set to 122 (244 usec) by default.

     hw.iavf.enable_head_writeback
             When the driver is finding the last TX descriptor processed by
             the hardware, use a value written to memory by the hardware
             instead of scanning the descriptor ring for completed
             descriptors.  Disabled by default; this mimics the "legacy" TX
             behavior found in ixgbe(4).  to ensure compatibility with future,
             non-700 series VF devices.

SUPPORT
     For general information and support, go to the Intel support website at:
     http://support.intel.com/.

     If an issue is identified with this driver with a supported adapter,
     email all the specific information related to the issue to
     freebsd@intel.com.

SEE ALSO
     arp(4), ixl(4), netintro(4), vlan(4), ifconfig(8), iflib(9)

HISTORY
     The iavf device driver first appeared in FreeBSD 10.1.  under the name
     "ixlv" It was converted to use iflib(9) and changed to its current name
     in FreeBSD 12.

AUTHORS
     The iavf driver was written by Jack Vogel <jfv@freebsd.org> and Eric
     Joyner <erj@freebsd.org>.

CAVEATS
     This driver is supposed to function on VFs spawned from future network
     devices by Intel, but at the time of this writing, has only been tested
     on the 700 series VFs.

FreeBSD 13.1-RELEASE-p6        January 30, 2019        FreeBSD 13.1-RELEASE-p6