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.