ALC(4) BSD Kernel Interfaces Manual ALC(4)NAMEalc — Atheros AR8131/AR8132 Gigabit/Fast Ethernet driver
SYNOPSIS
To compile this driver into the kernel, place the following lines in your
kernel configuration file:
device miibus
device alc
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
if_alc_load="YES"
DESCRIPTION
The alc device driver provides support for Atheros AR8131 PCI Express
Gigabit Ethernet controllers and Atheros AR8132 PCI Express Fast Ethernet
controllers.
All LOMs supported by the alc driver have TCP/UDP/IP checksum offload for
transmit, TCP segmentation offload (TSO), hardware VLAN tag strip‐
ping/insertion features, Wake On Lan (WOL) and an interrupt moderation
mechanism as well as a 64-bit multicast hash filter.
The AR8131/AR8132 supports Jumbo Frames (up to 9216 bytes), which can be
configured 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 alc driver supports the following media types:
autoselect Enable autoselection of the media type and options. The
user can manually override the autoselected mode by adding
media options to rc.conf(5).
10baseT/UTP Set 10Mbps operation.
100baseTX Set 100Mbps (Fast Ethernet) operation.
1000baseTX Set 1000baseTX operation over twisted pair.
The alc driver supports the following media options:
full-duplex Force full duplex operation.
half-duplex Force half duplex operation.
For more information on configuring this device, see ifconfig(8).
HARDWARE
The alc device driver provides support for the following Ethernet con‐
trollers:
· Atheros AR8131 PCI Express Gigabit Ethernet controller
· Atheros AR8132 PCI Express Fast Ethernet controller
LOADER TUNABLES
Tunables can be set at the loader(8) prompt before booting the kernel or
stored in loader.conf(5).
hw.alc.msi_disable
This tunable disables MSI support on the Ethernet hardware. The
default value is 0.
hw.alc.msix_disable
This tunable disables MSI-X support on the Ethernet hardware.
The default value is 0.
SYSCTL VARIABLES
The following variables are available as both sysctl(8) variables and
loader(8) tunables:
dev.alc.%d.int_rx_mod
Maximum amount of time to delay receive interrupt processing in
units of 1us. The accepted range is 0 to 130000, the default is
100(100us). Value 0 completely disables the interrupt modera‐
tion.
dev.alc.%d.int_tx_mod
Maximum amount of time to delay transmit interrupt processing in
units of 1us. The accepted range is 0 to 130000, the default is
50000(50ms). Value 0 completely disables the interrupt modera‐
tion.
dev.alc.%d.process_limit
Maximum amount of Rx frames to be processed in the event loop
before rescheduling a taskqueue. The accepted range is 32 to
255, the default value is 64 events. The interface does not need
to be brought down and up again before a change takes effect.
SEE ALSOaltq(4), arp(4), ifmedia(4), miibus(4), netintro(4), ng_ether(4),
vlan(4), ifconfig(8)HISTORY
The alc driver was written by Pyun YongHyeon ⟨yongari@FreeBSD.org⟩. It
first appeared in FreeBSD 8.0.
It was imported into DragonFly 2.5 by Matt Dillon based on a port by
Samuel J. Greear.
BSD February 14, 2010 BSD
