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SK(4)                  FreeBSD Kernel Interfaces Manual                  SK(4)

     sk -- SysKonnect SK-984x and SK-982x PCI Gigabit Ethernet adapter driver

     To compile this driver into the kernel, place the following lines in your
     kernel configuration file:

           device miibus
           device sk

     Alternatively, to load the driver as a module at boot time, place the
     following line in loader.conf(5):


     The sk driver provides support for the SysKonnect SK-984x and SK-982x
     series PCI Gigabit Ethernet adapters.

     The SysKonnect adapters consist of two main components: the XaQti Corp.
     XMAC II gigabit MAC and the SysKonnect GEnesis controller ASIC.  The XMAC
     provides the gigabit MAC and PHY support while the GEnesis 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 SK-982x 1000baseT adapters also include a Broadcom BCM5400 1000baseTX
     PHY which is used in place of the XMAC's internal PHY.  The Broadcom PHY
     is connected to the XMAC via its GMII port.

     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 SysKonnect driver software currently only uses the second
     port on dual port adapters for failover purposes: if the link on the pri-
     mary port fails, the SysKonnect driver will automatically switch traffic
     onto the second port.

     Also supported is the Marvell Semiconductor 88E1000* gigabit PHY.

     The XaQti XMAC II supports full and half duplex operation with autonego-
     tiation.  The XMAC also supports unlimited frame sizes.  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.  Using jumbo frames can
     greatly improve performance for certain tasks, such as file transfers and
     data streaming.

     The sk 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 the /etc/rc.conf

     1000baseTX            Set 1000baseTX operation over twisted pair.  This
                           is only available for SK-982x series adapters with
                           1000baseT ports.  Both full-duplex and half-duplex
                           modes are supported.

     1000baseSX            Set 1000Mbps (Gigabit Ethernet) operation.  Both
                           full-duplex and half-duplex modes are supported.

     The sk driver supports the following media options:

     full-duplex           Force full duplex operation

     half-duplex           Force half duplex operation.

     The sk driver also supports one special link option for 1000baseTX cards:

     link0                 With 1000baseTX cards, establishing a link between
                           two ports requires that one port is configured as
                           master and the other one as slave.  With autonego-
                           tiation, the master/slave settings will be chosen
                           automatically.  However when manually selecting the
                           link state, it is necessary to force one side of
                           the link to be a master and the other a slave.  The
                           sk driver configures the ports as slaves by
                           default.  Setting the link0 flag with ifconfig(8)
                           will set a port as a master instead.

     For more information on configuring this device, see ifconfig(8).

     Adapters supported by the sk driver include:

     +o   3Com 3C940 single port, 1000baseT adapter
     +o   3Com 3C2000-T single port, 1000baseT adapter
     +o   Belkin F5D5005 single port, 1000baseT adapter
     +o   D-Link DGE-530T single port, 1000baseT adapter
     +o   Linksys EG1032 single port, 1000baseT adapter
     +o   SK-9521 SK-NET GE-T single port, 1000baseT adapter
     +o   SK-9821 SK-NET GE-T single port, 1000baseT adapter
     +o   SK-9822 SK-NET GE-T dual port, 1000baseT 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   SMC 9452TX single port, 1000baseT adapter

     The following variable is available as both sysctl(8) variable and
     loader(8) tunable:


             This variable controls interrupt moderation.  The accepted range
             is 10 to 10000, default value is 100 microseconds.  The interface
             has to be brought down and up again before a change takes effect.

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

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

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

     sk%d: no memory for softc struct!  The driver failed to allocate memory
     for per-device instance information during initialization.

     sk%d: failed to enable memory mapping!  The driver failed to initialize
     PCI shared memory mapping.  This might happen if the card is not in a
     bus-master slot.

     sk%d: no memory for jumbo buffers!  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).

     arp(4), miibus(4), netintro(4), ng_ether(4), vlan(4), ifconfig(8)

     XaQti XMAC II datasheet,

     SysKonnect GEnesis programming manual,

     The sk device driver first appeared in FreeBSD 3.0.

     The sk driver was written by Bill Paul <>.

FreeBSD 6.2                      July 16, 2005                     FreeBSD 6.2


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