NAME
jme - JMicron Gigabit/Fast Ethernet driver
SYNOPSIS
To compile this driver into the kernel, place the following lines in your
kernel configuration file:
device miibus
device jme
Alternatively, to load the driver as a module at boot time, place the
following line in loader.conf(5):
if_jme_load="YES"
DESCRIPTION
The jme device driver provides support for JMicron JMC250 PCI Express
Gigabit Ethernet controllers and JMicron JMC260 PCI Express Fast Ethernet
controllers.
All LOMs supported by the jme driver have TCP/UDP/IP checksum offload for
both transmit and receive, TCP segmentation offload (TSO), hardware VLAN
tag stripping/insertion features, Wake On Lan (WOL) and an interrupt
coalescing/moderation mechanism as well as a 64-bit multicast hash
filter.
The JMC250 also 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 jme 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 jme 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 jme device driver provides support for the following Ethernet
controllers:
· JMicron JMC250 PCI Express Gigabit Ethernet controller
· JMicron JMC260 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.jme.msi_disable
This tunable disables MSI support on the Ethernet hardware. The
default value is 0.
hw.jme.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.jme.%d.tx_coal_to
Maximum amount of time to delay for Tx completion interrupt in
units of 1us. The accepted range is 1 to 65535, the default is
100 (100us).
dev.jme.%d.tx_coal_pkt
Maximum number of packets to fire Tx completion interrupt. The
accepted range is 1 to 255, the default is 8.
dev.jme.%d.rx_coal_to
Maximum amount of time to delay for Rx completion interrupt in
units of 1us. The accepted range is 1 to 65535, the default is
100 (100us).
dev.jme.%d.rx_coal_pkt
Maximum number of packets to fire Rx completion interrupt. The
accepted range is 1 to 255, the default is 2.
dev.jme.%d.process_limit
Maximum amount of Rx events to be processed in the event loop
before rescheduling a taskqueue. The accepted range is 10 to
255, the default value is 128 events. The interface does not
need to be brought down and up again before a change takes
effect.
SEE ALSO
altq(4), arp(4), miibus(4), netintro(4), ng_ether(4), vlan(4),
ifconfig(8)
HISTORY
The jme driver was written by Pyun YongHyeon 〈yongari@FreeBSD.org〉. It
first appeared in FreeBSD 7.1.