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

NAME
     sk, skc, msk, mskc - SysKonnect XMAC II and Marvell Yukon based Gigabit
     Ethernet device

SYNOPSIS
     skc* at pci?
     sk* at skc?
     mskc* at pci?
     msk* at mskc?
     brgphy* at mii?
     eephy* at mii?
     xmphy* at mii?

DESCRIPTION
     The sk driver provides support for SysKonnect based Gigabit Ethernet
     adapters and Marvell based Gigabit Ethernet adapters, including the fol-
     lowing:

           o   3Com 3c940 single port, copper adapter
           o   3Com 3c2000-T single port, copper adapter
           o   Belkin F5D5005, copper adapter
           o   D-Link DGE-530T, copper adapter
           o   Linksys EG1032v2, copper adapter
           o   Linksys EG1064v2, copper adapter
           o   SK-9821 SK-NET GE-T single port, copper adapter
           o   SK-9822 SK-NET GE-T dual port, copper adapter
           o   SK-9841 SK-NET GE-LX single port, single mode fiber adapter
           o   SK-9842 SK-NET GE-LX dual port, single mode fiber adapter
           o   SK-9843 SK-NET GE-SX single port, multimode fiber adapter
           o   SK-9844 SK-NET GE-SX dual port, multimode fiber adapter
           o   SK-9521 V2.0 single port, copper adapter (32-bit)
           o   SK-9821 V2.0 single port, copper adapter
           o   SK-9843 V2.0 single port, copper adapter
           o   SMC 9452TX, copper adapter

     The msk driver provides support for the Marvell Yukon-2 based Gigabit
     Ethernet adapters, including the following:

           o   Marvell Yukon 88E8035, copper adapter
           o   Marvell Yukon 88E8036, copper adapter
           o   Marvell Yukon 88E8038, copper adapter
           o   Marvell Yukon 88E8050, copper adapter
           o   Marvell Yukon 88E8052, copper adapter
           o   Marvell Yukon 88E8053, copper adapter
           o   SK-9E21 1000Base-T single port, copper adapter
           o   SK-9E22 1000Base-T dual port, copper adapter
           o   SK-9E81 1000Base-SX single port, multimode fiber adapter
           o   SK-9E82 1000Base-SX dual port, multimode fiber adapter
           o   SK-9E91 1000Base-LX single port, single mode fiber adapter
           o   SK-9E92 1000Base-LX dual port, single mode fiber adapter
           o   SK-9S21 1000Base-T single port, copper adapter
           o   SK-9S22 1000Base-T dual port, copper adapter
           o   SK-9S81 1000Base-SX single port, multimode fiber adapter
           o   SK-9S82 1000Base-SX dual port, multimode fiber adapter
           o   SK-9S91 1000Base-LX single port, single mode fiber adapter
           o   SK-9S92 1000Base-LX dual port, single mode fiber adapter
           o   SK-9E21D 1000Base-T single port, copper adapter

     The SysKonnect based adapters consist of two main components: the XaQti
     Corp. XMAC II Gigabit MAC (sk) and the SysKonnect GEnesis controller ASIC
     (skc).  The XMAC provides the Gigabit MAC and PHY support while the GEne-
     sis provides an interface to the PCI bus, DMA support, packet buffering
     and arbitration.  The GEnesis can control up to two XMACs simultaneously,
     allowing dual-port NIC configurations.

     The Marvell based adapters are a single integrated circuit, but are still
     presented as a separate MAC (sk) and controller ASIC (skc).

     The sk driver configures dual port SysKonnect adapters such that each
     XMAC is treated as a separate logical network interface.  Both ports can
     operate independently of each other and can be connected to separate net-
     works.

     The XaQti XMAC II supports full and half duplex operation with autonego-
     tiation.  The XMAC also supports a frame size of up to 9000 bytes.  Sup-
     port for Jumbo frames is provided via the interface MTU setting.  Select-
     ing an MTU larger than 1500 bytes with the ifconfig(8) utility configures
     the adapter to transmit Jumbo frames.  Using Jumbo frames can greatly im-
     prove performance for certain tasks, such as file transfers and data
     streaming.

     Hardware receive IP checksum offload for IPv4 is supported.

     The following media types and options (as given to ifconfig(8)) are sup-
     ported:

           media autoselect
                Enable autoselection of the media type and options.  The user
                can manually override the autoselected mode by adding media
                options to the appropriate hostname.if(5) file.

           media 1000baseSX mediaopt full-duplex
                Set 1000Mbps (Gigabit Ethernet) operation on fiber and force
                full-duplex mode.

           media 1000baseSX mediaopt half-duplex
                Set 1000Mbps (Gigabit Ethernet) operation on fiber and force
                half-duplex mode.

           media 1000baseT mediaopt full-duplex
                Set 1000Mbps (Gigabit Ethernet) operation and force full-du-
                plex mode.

     For more information on configuring this device, see ifconfig(8).  To
     view a list of media types and options supported by the card, try
     ifconfig -m <device>.  For example, ifconfig -m sk0.

DIAGNOSTICS
     sk%d: can't map mem space  A fatal initialization error has occurred.

     sk%d: couldn't map interrupt  A fatal initialization error has occurred.

     sk%d: no memory for jumbo buffer queue!  The driver failed to allocate
     memory for jumbo frames during initialization.

     sk%d: watchdog timeout  The device has stopped responding to the network,
     or there is a problem with the network connection (cable).

SEE ALSO
     arp(4), brgphy(4), eephy(4), ifmedia(4), intro(4), netintro(4), pci(4),
     xmphy(4), hostname.if(5), ifconfig(8)

     XaQti XMAC II datasheet, http://www.xaqti.com.

     SysKonnect GEnesis programming manual, http://www.syskonnect.com.

HISTORY
     The sk device driver first appeared in FreeBSD 3.0, and OpenBSD support
     was added in OpenBSD 2.6.

     The msk driver first appeared in OpenBSD 4.0.

AUTHORS
     The sk driver was written by Bill Paul <wpaul@ctr.columbia.edu>.  Support
     for the Marvell Yukon-2 was added by Mark Kettenis
     <kettenis@openbsd.org>.

BUGS
     The msk driver does not support hardware receive IP checksum offload yet.

OpenBSD 4.0                      July 3, 1999                                3
