NAME
mxge - Myricom Myri10GE 10 Gigabit Ethernet adapter driver
SYNOPSIS
To compile this driver into the kernel, place the following lines in your
kernel configuration file:
device firmware
device mxge
Alternatively, to load the driver as a module at boot time, place the
following lines in loader.conf(5):
if_mxge_load="YES"
mxge_ethp_z8e_load="YES"
mxge_eth_z8e_load="YES"
mxge_rss_ethp_z8e_load="YES"
mxge_rss_eth_z8e_load="YES"
DESCRIPTION
The mxge driver provides support for PCI Express 10 Gigabit Ethernet
adapters based on the Myricom LANai Z8E chip. The driver supports
Transmit/Receive checksum offload, Jumbo Frames, TCP segmentation offload
(TSO) as well as Large Receive Offload (LRO). For further hardware
information, see http://www.myri.com/.
For questions related to hardware requirements, refer to the
documentation supplied with your Myri10GE adapter. All hardware
requirements listed apply to use with FreeBSD.
Support for Jumbo Frames is provided 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 maximum
MTU size for Jumbo Frames is 9000.
For more information on configuring this device, see ifconfig(8).
HARDWARE
The mxge driver supports 10 Gigabit Ethernet adapters based on the
Myricom LANai Z8E chips:
· Myricom 10GBase-CX4 (10G-PCIE-8A-C, 10G-PCIE-8AL-C)
· Myricom 10GBase-R (10G-PCIE-8A-R, 10G-PCIE-8AL-R)
· Myricom 10G XAUI over ribbon fiber (10G-PCIE-8A-Q, 10G-PCIE-8AL-Q)
LOADER TUNABLES
Tunables can be set at the loader(8) prompt before booting the kernel or
stored in loader.conf(5).
hw.mxge.flow_control_enabled
Whether or not hardware flow control is enabled on the adapter.
The default value is 1.
hw.mxge.intr_coal_delay
This value delays the generation of all interrupts in units of 1
microsecond. The default value is 30.
hw.mxge.skip_pio_read
This value determines whether or not the driver may omit doing a
PIO read in the interrupt handler which ensures that the
interrupt line has been deasserted when using xPIC interrupts. A
non-zero value may result in lower CPU overhead, however it may
also result in spurious interrupts. The default value is 0.
This tunable has no effect when the device is using MSI or MSI-X
interrupts.
hw.mxge.max_slices
This value determines the maximum number of slices the driver
will attempt to use. The default value is 1. A slice is
comprised of a set of receive queues and an associated interrupt
thread. When using multiple slices, the NIC hashes traffic to
different slices based on the value of hw.mxge.rss_hashtype.
Using multiple slices requires that your motherboard and Myri10GE
NIC both be capable of MSI-X. Older Myri10GE NICs can be field
upgraded to add MSI-X using the "10G NIC Tool Kit" for FreeBSD
which is available from
http://www.myri.com/scs/download-10g-tools.html.
hw.mxge.rss_hashtype
This value determines how incoming traffic is steered to
different slices. This tunable is ignored when using just a
single slice. The legal values for this tunable are:
1 Hash on the source and destination IPv4 addresses.
2 Hash on source and destination IPv4 addresses and if the
packet is TCP, then also hash on the TCP source and
destination ports.
4 Hash on the TCP or UDP source ports. This is the default
value.
DIAGNOSTICS
mxge%d: Unable to allocate bus resource: memory A fatal initialization
error has occurred.
mxge%d: Unable to allocate bus resource: interrupt A fatal
initialization error has occurred.
mxge%d: Could not find firmware image %s The appropriate firmware kld
module was not installed. This is a non-fatal initialization error, but
will result in running in a reduced performance mode.
SUPPORT
For general information and support, go to the Myricom support website
at: http://www.myri.com/scs/.
If an issue is identified with the released source code on the supported
kernel with a supported adapter, email the specific information related
to the issue to 〈help@myri.com〉.
SEE ALSO
altq(4), arp(4), netintro(4), ng_ether(4), ifconfig(8)
HISTORY
The mxge device driver first appeared in FreeBSD 6.3.
AUTHORS
The mxge driver was written by Andrew Gallatin 〈gallatin@FreeBSD.org〉.