BSP Developer's Guide

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Upgrading 4.3 BSD Network Drivers
! CAUTION: When converting a BSD 4.3 network driver code to an END, you must
replace all calls into the protocol with appropriate calls to the MUX. Also, you must
remove all code that implements or uses the etherInputHook( ) and
etherOutputHook( ) routines.
Rewrite xxattach( ) to Use an endLoad( ) Interface
Rewrite the interface of your xxattach( ) to match the endLoad( ) entry point
described in Loading the Device: endLoad( ), p.290.
Much of the code that handles the specifics of hardware initialization should be the
same. However, when allocating the memory for packet reception buffers that are
passed up to the protocol, you should use the MUX buffer management utilities.
See H.3.1 Setting Up and Using a Memory Pool for Receive and Transmit Buffers, as well
as the reference entry for muxBufInit( ).
Remove any code your xxattach( ) included to support the implementation of the
etherInputHook( ) and etherOutputHook( ) routines.
xxReceive( ) Still Handles Task-Level Packet Reception
Because the MUX does not directly call the driver’s packet reception code, there is
no endReceive( ) entry point. However, your driver still needs to handle packet
reception at the task level. Unfortunately, most of the code in this driver routine
requires extensive revision. Instead of calling the protocol directly, this routine
uses a MUX-supplied function to pass a packet up to the protocol (see
H.3 Guidelines for Handling Packet Reception in Your Driver). Also, your receive
routine should use the MUX-managed memory pool as its receive buffer area.
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Rewrite xxOutput( ) to Use an endSend( ) Interface
Rewrite the interface of your xxOutput( ) to match the endSend( ) routine
described in Sending Data Out on the Device: endSend( ), p.293.
Much of the code that dealt directly with putting the packet on the hardware
should need little if any revision. However, you should change your code to use
mblk chains allocated out of an endBufLib-managed memory pool. For more
information, see the reference entry for netBufLib.
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