.\" Copyright (c) 2013-2018, Intel Corporation
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions are met:
.\"
.\"  1. Redistributions of source code must retain the above copyright notice,
.\"     this list of conditions and the following disclaimer.
.\"
.\"  2. Redistributions in binary form must reproduce the above copyright
.\"     notice, this list of conditions and the following disclaimer in the
.\"     documentation and/or other materials provided with the distribution.
.\"
.\"  3. Neither the name of the Intel Corporation nor the names of its
.\"     contributors may be used to endorse or promote products derived from
.\"     this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
.\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.\" * Other names and brands may be claimed as the property of others.
.\"
.\" $FreeBSD$
.\"
.Dd October 5, 2018
.Dt IAVF 4
.Os
.Sh NAME
.Nm iavf
.Nd "Intel Adaptive Virtual Function driver"
.Sh SYNOPSIS
To compile this driver into the kernel, place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device iavf"
.Ed
.Pp
To load the driver as a module at boot time, place the following lines in
.Xr loader.conf 5 :
.Bd -literal -offset indent
if_iavf_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
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
.Pa http://support.intel.com/ .
.Pp
Support for Jumbo Frames is provided via the interface MTU setting.
Selecting an MTU larger than 1500 bytes with the
.Xr ifconfig 8
utility configures the adapter to receive and transmit Jumbo Frames.
The maximum MTU size for Jumbo Frames is 9706.
.Pp
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.
.Pp
For more information on configuring this device, see
.Xr ifconfig 8 .
.Pp
.Em NOTE :
This
.Nm
driver is only for Virtual Functions.
For 700 series Physical Functions, use the
.Xr ixl 4
driver.
.Sh LOADER TUNABLES
Tunables can be set at the
.Xr loader 8
prompt before booting the kernel or stored in
.Xr loader.conf 5 .
.Bl -tag -width indent
.It Va hw.iavf.rx_itr
The RX interrupt rate value, set to 62 (124 usec) by default.
.It Va hw.iavf.tx_itr
The TX interrupt rate value, set to 122 (244 usec) by default.
.It Va 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
.Xr ixgbe 4 .
to ensure compatibility with future, non-700 series VF devices.
.El
.Sh SUPPORT
For general information and support,
go to the Intel support website at:
.Pa http://support.intel.com/ .
.Pp
If an issue is identified with this driver with a supported adapter,
email all the specific information related to the issue to
.Mt freebsd@intel.com .
.Sh SEE ALSO
.Xr arp 4 ,
.Xr ixl 4 ,
.Xr netintro 4 ,
.Xr vlan 4 ,
.Xr ifconfig 8 ,
.Xr iflib 9
.Sh HISTORY
The
.Nm
device driver first appeared in
.Fx 10.1 .
under the name "ixlv"
It was converted to use
.Xr iflib 9
and changed to its current name in
.Fx 12 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Jack Vogel Aq Mt jfv@freebsd.org
and
.An Eric Joyner Aq Mt erj@freebsd.org .
.Sh 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.