ET (4)
BSD 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).
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 pre-
vent 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 underflo