ae —
Attansic/Atheros L2 FastEthernet
controller driver
To compile this driver into the kernel, place the following lines
in your kernel configuration file:
device miibus
device ae
Alternatively, to load the driver as a module at boot time, place
the following line in
loader.conf(5):
The ae device driver provides support for
Attansic/Atheros L2 PCIe FastEthernet controllers.
The controller supports hardware Ethernet checksum processing,
hardware VLAN tag stripping/insertion and an interrupt moderation mechanism.
Attansic L2 also features a 64-bit multicast hash filter.
The ae 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
- Select 10Mbps operation.
100baseTX
- Set 100Mbps (FastEthernet) operation.
The ae driver provides support for 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).
The ae driver supports Attansic/Atheros L2
PCIe FastEthernet controllers, and is known to support the following
hardware:
- ASUS EeePC 701
- ASUS EeePC 900
Other hardware may or may not work with this driver.
Tunables can be set at the
loader(8) prompt before booting the kernel or stored in
loader.conf(5).
- hw.ae.msi_disable
- This tunable disables MSI support on the Ethernet hardware. The default
value is 0.
The ae driver collects a number of useful
MAC counter during the work. The statistics is available via the
dev.ae.%d.stats
sysctl(8) tree, where %d corresponds to the controller
number.
- ae%d: watchdog timeout.
- The device has stopped responding to the network, or there is a problem
with the network connection (cable).
- ae%d: reset timeout.
- The card reset operation has been timed out.
- ae%d: Generating random ethernet address.
- No valid Ethernet address was found in the controller NVRAM and registers.
Random locally administered address with ASUS OUI identifier will be used
instead.
The ae driver and this manual page was
written by Stanislav Sedov
<stas@FreeBSD.org>.
It first appeared in FreeBSD 7.1.
The Attansic L2 FastEthernet controller supports DMA but does not
use a descriptor based transfer mechanism via scatter-gather DMA. Thus the
data should be copied to/from the controller memory on each
transmit/receive. Furthermore, a lot of data alignment restrictions apply.
This may introduce a high CPU load on systems with heavy network activity.
Luckily enough this should not be a problem on modern hardware as L2 does
not support speeds faster than 100Mbps.