ET(4)

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

SYNOPSIS
device miibus
device et

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

    if_et_load="YES"

DESCRIPTION
The et driver supports the PCIe Ethernet adapters based on Agere ET1310.

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 setting for Jumbo Frames is 15572. This value coincides with the maximum Jumbo Frames size of 15594.

The et driver supports the following media types:

autoselect
    Enable autoselection of the media types and options

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 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).

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 129. It is recommended to set this value above 38 to prevent 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 25.

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 256. It is recommended to set this value below 280 to prevent TX ring from underflow.

hw.et.timer
    This value controls how often the 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
arp(4), ifmedia(4), miibus(4), netintro(4), ng_ether(4), vlan(4), ifconfig(8)

HISTORY
The et device driver first appeared in DragonFly 1.11.

AUTHORS
-nosplit The et driver was written by Sepherosa Ziehau <sepherosa@gmail.com>.