WB(4)

NAME
wb - Winbond W89C840F 10/100 Ethernet device

SYNOPSIS
wb* at pci?
amphy* at mii?

DESCRIPTION
The wb driver provides support for PCI Ethernet adapters and embedded controllers based on the Winbond W89C840F Fast Ethernet controller chip. This includes the TRENDnet TE100-PCIE and various other cheap boards. The 840F should not be confused with the 940F, which is an NE2000 clone and only supports 10Mbps speeds.

The Winbond controller uses bus master DMA and is designed to be a DEC "tulip" work-alike. It differs from the standard DEC design in several ways: the control and status registers are spaced 4 bytes apart instead of 8, and the receive filter is programmed through registers rather than by downloading a special setup frame via the transmit DMA engine. Using an external PHY, the Winbond chip supports both 10 and 100Mbps speeds in either full or half duplex.

The wb 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 Winbond controller supports NWAY autonegotiation. The user can manually 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 wb 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

wb0: couldn't map memory A fatal initialization error has occurred.

wb0: couldn't map interrupt A fatal initialization error has occurred.

wb0: watchdog timeout The device has stopped responding to the network, or there is a problem with the network connection (cable).

wb0: no memory for rx list The driver failed to allocate an mbuf for the receiver ring.

wb0: 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.

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

HISTORY
The wb device driver first appeared in FreeBSD 3.0. OpenBSD support first appeared in OpenBSD 2.5.

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

BUGS
The Winbond chip seems to behave strangely in some cases when the link partner switches modes. If, for example, both sides are set to 10Mbps half-duplex, and the other end is changed to 100Mbps full-duplex, the Winbond's receiver suddenly starts writing trash all over the RX descriptors. The wb driver handles this by forcing a reset of both the controller chip and attached PHY. This is drastic, but it appears to be the only way to recover properly from this condition.