RL(4)                     OpenBSD Programmer's Manual                    RL(4)

NAME
     rl - Realtek 8129/8139 10/100 Ethernet device

SYNOPSIS
     rl* at pci?
     rl* at cardbus?
     rlphy* at mii?

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, among others, the following cards:

           Accton MPX5030 CardBus
           Allied Telesyn AT2550
           Corega FEther CB-TXD 10/100 Ethernet
           D-Link DFE530TX+, DFE538TX, DFE-690TXD
           Encore ENL832-TX-RENT 10/100 M PCI
           Genius GF100TXR
           KTX-9130TX 10/100 Fast Ethernet
           Longshine LCS-8038TX-R
           NDC Communications NE100TX-E
           Netgear FA311 v2
           Netronix Inc. EA-1210 NetEther 10/100
           Nortel BayStack 21
           OvisLink LEF-8129TX, LEF-8139TX
           SMC EZ Card 10/100 PCI 1211-TX
           TRENDnet TE100-PCBUSR CardBus

     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 con-
                  troller supports NWAY autonegotiation.  The user can manual-
                  ly override the autoselected mode by adding media options to
                  the appropriate hostname.if(5) file.

     10baseT      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 this message appears at boot time and the driver fails to attach the
     device as a network interface, a second warm boot will have to be per-
     formed to have the device properly configured.

     Note that this condition only occurs when warm booting from another oper-
     ating system.  If the system is powered down prior to booting OpenBSD,
     the card should be configured correctly.

SEE ALSO
     arp(4), ifmedia(4), intro(4), netintro(4), rlphy(4), hostname.if(5),
     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.  OpenBSD support
     first appeared in OpenBSD 2.5.

AUTHORS
     The rl driver was written by Bill Paul <wpaul@ctr.columbia.edu>.

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 preceding 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.

OpenBSD 4.7                      May 31, 2007                                3
