NAME
rl - RealTek
8129/8139 fast ethernet device driver
SYNOPSIS
device rl
DESCRIPTION
The rl driver
provides support for PCI ethernet adapters and embedded
controllers
based on the RealTek 8129 and 8139 fast ethernet controller
chips. This includes the Allied Telesyn
AT2550, Genius GF100TXR, NDC
Communications NE100TX-E,
OvisLink LEF-8129TX, OvisLink LEF-8139TX,
Netronix Inc.
EA-1210 NetEther 10/100, KTX-9130TX 10/100 Fast Ethernet,
Encore
ENL832-TX 10/100 M PCI, Longshine LCS-8038TX-R, the SMC EZ Card
10/100 PCI
1211-TX, and various other cheap adapters. It also supports
the Accton
EN1207D which has a chip labeled MPX5030 (or MPX5038) which
appears to be a
RealTek workalike.
The RealTek
controllers use bus master DMA but do not use a descriptor-
based data
transfer mechanism. The receiver
uses a single fixed size
ring buffer
from which packets must be copied into mbufs. For transmis-
sion, there are
only four outbound packet address registers which require
all outgoing
packets to be stored as contiguous buffers. Furthermore,
outbound packet
buffers must be longword aligned or else transmission
will fail.
The 8129
differs from the 8139 in that the 8139 has an internal PHY which
is controlled
through special direct access registers whereas the 8129
uses an
external PHY via an MII bus. The
8139 supports both 10 and
100Mbps speeds
in either full or half duplex. The
8129 can support the
same speeds and
modes given an appropriate PHY chip.
The rl driver
supports the following media types:
autoselect
Enable autoselection of the media type and options.
This is only supported if the PHY chip attached to
the RealTek controller supports NWAY autonegotia-
tion. The user can manually
override the autose-
lected mode by adding media options to the
/etc/rc.conf file.
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.
The rl driver
supports the following media options:
full-duplex Force
full duplex operation
half-duplex Force half duplex
operation.
Note that the
100baseTX media type is only available if supported by the
adapter. For more information on configuring
this device, see
ifconfig(8).
DIAGNOSTICS
rl%d: couldn't
map memory A fatal initialization
error has occurred.
rl%d: couldn't
map interrupt A fatal
initialization error has occurred.
rl%d: watchdog
timeout The device has stopped
responding to the network,
or there is a problem with the network
connection (cable).
rl%d: no memory
for rx list The driver failed to
allocate an mbuf for
the receiver
ring.
rl%d: no memory
for tx list The driver failed to
allocate an mbuf for
the transmitter
ring when allocating a pad buffer or collapsing an mbuf
chain into a
cluster.
rl%d: chip is
in D3 power state -- setting to D0
This message applies
only to
adapters which support power management.
Some operating systems
place the
controller in low power mode when shutting down, and some PCI
BIOSes fail to
bring the chip out of this state before configuring it.
The controller
loses all of its PCI configuration in the D3 state, so if
the BIOS does
not set it back to full power mode in time, it won't be
able to
configure it correctly. The driver
tries to detect this condi-
tion and bring
the adapter back to the D0 (full power) state, but this
may not be
enough to return the driver to a fully operational condition.
If you see this
message at boot time and the driver fails to attach the
device as a
network interface, you will have to perform second warm boot
to have the
device properly configured.
Note that this
condition only occurs when warm booting from another oper-
ating
system. If you power down your
system prior to booting FreeBSD,
the card should
be configured correctly.
SEE
ALSO
arp(4), netintro(4), ng_ether(4),
ifconfig(8)
The RealTek 8129
and 8139 datasheets, ftp.realtek.com.tw:/lancard/data
sheet.
HISTORY
The rl device
driver first appeared in FreeBSD 3.0.
AUTHORS
The rl driver was written by Bill Paul <wpaul@ctr.columbia.edu>.
http://people.freebsd.org/~wpaul/RealTek/
BUGS
Since outbound packets
must be longword aligned, the transmit routine has
to copy an
unaligned packet into an mbuf cluster buffer before transmis-
sion. The driver abuses the fact that the
cluster buffer pool is allo-
cated at system
startup time in a contiguous region starting at a page
boundary. Since cluster buffers are 2048 bytes,
they are longword
aligned by
definition. The driver probably
should not be depending on
this
characteristic.
The RealTek
data sheets are of especially poor quality: the grammar and
spelling are
awful and there is a lot of information missing, particular-
ly concerning
the receiver operation. One
particularly important fact
that the data
sheets fail to mention relates to the way in which the chip
fills in the
receive buffer. When an interrupt
is posted to signal that
a frame has
been received, it is possible that another frame might be in
the process of
being copied into the receive buffer while the driver is
busy handling the first one. If the driver manages to finish
processing
the first frame
before the chip is done DMAing the rest of the next
frame, the
driver may attempt to process the next frame in the buffer be-
fore the chip
has had a chance to finish DMAing all of it.
The driver can
check for an incomplete frame by inspecting the frame
length in the
header preceeding the actual packet data: an incomplete
frame will have
the magic length of 0xFFF0. When the
driver encounters
this value, it
knows that it has finished processing all currently avail-
able
packets. Neither this magic value
nor its significance are docu-
mented anywhere
in the RealTek data sheets.
FreeBSD November 4, 1998