ET(4)                  FreeBSD Kernel Interfaces Manual                  ET(4)

NAME
     et - Agere ET1310 10/100/Gigabit Ethernet driver

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

           device miibus
           device et

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

           if_et_load="YES"

DESCRIPTION
     The et driver supports PCI Express Ethernet adapters based on the Agere
     ET1310 chip.

     The et driver supports the following media types:

     autoselect   Enable autoselection of the media types and options.  The
                  user can manually override the autoselected mode by adding
                  media options to the /etc/rc.conf file.

     10baseT/UTP  Set 10Mbps operation.  The mediaopt option can also be used
                  to select either full-duplex or half-duplex modes.

     100baseTX    Set 100Mbps (Fast Ethernet) operation.  The mediaopt option
                  can also be used to select either full-duplex or half-duplex
                  modes.

     1000baseT    Set 1000Mbps (Gigabit Ethernet) operation.  The mediaopt
                  option can only be set to full-duplex mode.

     The et driver supports the following media options:

     full-duplex  Force full-duplex operation.

     half-duplex  Force half-duplex operation.

     Note that the 1000baseT media type is only available if it is supported
     by the adapter.  For more information on configuring this device, see
     ifconfig(8).

HARDWARE
     The et driver supports Agere ET1310 10/100/Gigabit Ethernet adapters.

TUNABLES
     hw.et.rx_intr_npkts      This value controls how many packets should be
                              received before a receive interrupt is
                              generated.  The default value is 32.  It is
                              recommended to set this value above 38 to
                              prevent the host from being livelocked under a
                              high degree of stress.

     hw.et.rx_intr_delay      This value delays the generation of receive
                              interrupts in units of ~4 microseconds.  It is
                              used together with hw.et.rx_intr_npkts to
                              achieve RX interrupt moderation.  The default
                              value is 20.

     hw.et.tx_intr_nsegs      This value controls how many segments (not
                              packets) should be transmitted before a transmit
                              interrupt is generated.  The default value is
                              126.  It is recommended to set this value below
                              280 to prevent the TX ring from underflowing.

     hw.et.timer              This value controls how often a timer interrupt
                              should be generated.  It is used together with
                              hw.et.tx_intr_nsegs to achieve TX interrupt
                              moderation.  The default value is 1000000000
                              (nanoseconds).

SEE ALSO
     altq(4), arp(4), miibus(4), netintro(4), ng_ether(4), vlan(4),
     ifconfig(8)

HISTORY
     The et device driver first appeared in DragonFly 1.11.  The first FreeBSD
     release to include it was FreeBSD 8.0.

AUTHORS
     The et driver was written by Sepherosa Ziehau <sepherosa@gmail.com> for
     DragonFly.  It was ported to FreeBSD by Xin LI <delphij@FreeBSD.org>.

FreeBSD 13.1-RELEASE-p6        December 9, 2011        FreeBSD 13.1-RELEASE-p6