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.Dd December 1, 2018
.Dt ENA 4
.Os
.Sh NAME
.Nm ena
.Nd NetBSD kernel driver for Elastic Network Adapter (ENA) family
.Sh SYNOPSIS
.Cd "ena* at pci? dev ? function ?"
.Sh DESCRIPTION
The ENA is a networking interface designed to make good use of modern CPU
features and system architectures.
.Pp
The ENA device exposes a lightweight management interface with a
minimal set of memory mapped registers and extendable command set
through an Admin Queue.
.Pp
The driver supports a range of ENA devices, is link-speed independent
(i.e., the same driver is used for 10GbE, 25GbE, 40GbE, etc.), and has
a negotiated and extendable feature set.
.Pp
Some ENA devices support SR-IOV.
This driver is used for both the
SR-IOV Physical Function (PF) and Virtual Function (VF) devices.
.Pp
The ENA devices enable high speed and low overhead network traffic
processing by providing multiple Tx/Rx queue pairs (the maximum number
is advertised by the device via the Admin Queue), a dedicated MSI-X
interrupt vector per Tx/Rx queue pair, and CPU cacheline optimized
data placement.
.Pp
The
.Nm
driver supports industry standard TCP/IP offload features such
as checksum offload and TCP transmit segmentation offload (TSO).
Receive-side scaling (RSS) is supported for multi-core scaling.
.Pp
The
.Nm
driver and its corresponding devices implement health
monitoring mechanisms such as watchdog, enabling the device and driver
to recover in a manner transparent to the application, as well as
debug logs.
.Pp
Some of the ENA devices support a working mode called Low-latency
Queue (LLQ), which saves several more microseconds.
This feature might be implemented for the driver in future releases.
.Sh HARDWARE
Supported PCI vendor ID/device IDs:
.Pp
.Bl -bullet -compact
.It
1d0f:0ec2 - ENA PF
.It
1d0f:1ec2 - ENA PF with LLQ support
.It
1d0f:ec20 - ENA VF
.It
1d0f:ec21 - ENA VF with LLQ support
.El
.Sh SEE ALSO
.Xr arp 4 ,
.Xr ifmedia 4 ,
.Xr netintro 4 ,
.Xr pci 4 ,
.Xr ifconfig 8
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was originally written by
.An Semihalf
for
.Fx .
The driver was ported to
.Nx
by
.An Jared D. McNeill Aq Mt jmcneill@NetBSD.org .