NAME

     en — device driver for Midway-based ATM interfaces

SYNOPSIS

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

           device en
           device atm
           device utopia

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

           if_en_load="YES"

DESCRIPTION

     The en device driver supports Midway-based ATM interfaces including the Efficient Networks,
     Inc. ENI-155 and Adaptec ANA-59x0.  Midway is an AAL5 SAR (Segmentation and Reassembly)
     chip.

     For configuring the card for IP see natmip(4).

     The following sysctls are recognized by the driver additionally to those handled by
     utopia(4):

     hw.atm.enX.istats
             Contains an array of uint32_t with internal driver statistics.

     hw.atm.enX.debug
             This is a bit map of debugging options.  This variable is only available when the
             driver is compiled with debugging support.

     The driver supports the media options sdh, noscramb and unassigned (see utopia(4)).

DIAGNOSTICS

     en0 <Efficient Networks ENI-155p> rev 0 int a irq 5 on pci0:16
     en0: ATM midway v0, board IDs 6.0, Utopia (pipelined), 512KB on-board RAM
     en0: maximum DMA burst length = 64 bytes
     en0: 7 32KB receive buffers, 8 32KB transmit buffers allocated

SEE ALSO

     natm(4), natmip(4), utopia(4), ifconfig(8), route(8)

AUTHORS

     Chuck Cranor of Washington University implemented en driver in 1996 for NetBSD.

CAVEATS

     The driver extensively uses DMA on PCI.  The first generation PCI chipsets do not work or
     exhibit poor performance.