DragonFly On-Line Manual Pages


ET(4)		      DragonFly Kernel Interfaces Manual		 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 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 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

The et driver was written by Sepherosa Ziehau <sepherosa@gmail.com>. DragonFly 3.7 July 9, 2008 DragonFly 3.7