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VR(4)                  FreeBSD Kernel Interfaces Manual                  VR(4)

     vr - VIA Technologies Rhine I/II/III Ethernet device driver

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

           device miibus
           device vr

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


     The vr driver provides support for PCI Ethernet adapters and embedded
     controllers based on the VIA Technologies VT3043 Rhine I, VT86C100A Rhine
     II, and VT6105/VT6105M Rhine III Fast Ethernet controller chips.

     The VIA Rhine chips use bus master DMA and have a descriptor layout
     designed to resemble that of the DEC 21x4x ``tulip'' chips.  The register
     layout is different however and the receive filter in the Rhine chips is
     much simpler and is programmed through registers rather than by
     downloading a special setup frame through the transmit DMA engine.
     Transmit and receive DMA buffers must be longword aligned.  The Rhine
     chips are meant to be interfaced with external physical layer devices via
     an MII bus.  They support both 10 and 100Mbps speeds in either full or
     half duplex.

     The vr 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

     10baseT/UTP           Set 10Mbps operation.  The mediaopt option can also
                           be used to select either full-duplex or half-duplex

     100baseTX             Set 100Mbps (Fast Ethernet) operation.  The
                           mediaopt option can also be used to select either
                           full-duplex or half-duplex modes.

     The vr 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

     The vr driver supports VIA Technologies Rhine I, Rhine II, and Rhine III
     based Fast Ethernet adapters including:

        AOpen/Acer ALN-320
        D-Link DFE520-TX
        D-Link DFE530-TX
        Hawking Technologies PN102TX
        Soekris Engineering net5501

     The following variables are available as sysctl(8) variables:

             Display lots of useful MAC counters maintained in the driver.

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

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

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

     vr%d: no memory for rx list  The driver failed to allocate an mbuf for
     the receiver ring.

     vr%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.

     vr%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 will not be
     able to configure it correctly.  The driver tries to detect this
     condition 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
     operating system.  If you power down your system prior to booting
     FreeBSD, the card should be configured correctly.

     altq(4), arp(4), miibus(4), netintro(4), ng_ether(4), polling(4),

     The VIA Technologies VT86C100A data sheet,

     The vr device driver first appeared in FreeBSD 3.0.

     The vr driver was written by Bill Paul <[email protected]>.

     The vr driver always copies transmit mbuf chains into longword-aligned
     buffers prior to transmission in order to pacify the Rhine chips.  If
     buffers are not aligned correctly, the chip will round the supplied
     buffer address and begin DMAing from the wrong location.  This buffer
     copying impairs transmit performance on slower systems but cannot be
     avoided.  On faster machines (e.g. a Pentium II), the performance impact
     is much less noticeable.

FreeBSD 11.1-RELEASE-p4        February 25, 2012       FreeBSD 11.1-RELEASE-p4
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