ET(4) BSD Kernel Interfaces Manual ET(4)NAMEet — 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 con‐
figures 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 live‐
locked under a high degree of stress.
hw.et.rx_intr_delay This value delays the generation of receive inter‐
rupts 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 recom‐
mended 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 modera‐
tion. The default value is 1000000000 (nanosec‐
onds).
SEE ALSOarp(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
The et driver was written by Sepherosa Ziehau ⟨sepherosa@gmail.com⟩.
BSD July 9, 2008 BSD
