BSP Developer's Guide

VxWorks 5.5
BSP Developer’s Guide
work that is now handled in the TCP/IP stack. Thus, in a 4.4 BSD driver, this code
is unnecessary and should be removed.
G.2.2 Changing the Transmit Startup Routine
Under 4.3 BSD, the function prototype for a transmit startup routine is as follows:
static void xxTxStartup (int unit);
Under 4.4 BSD, the prototype has changed to the following:
static void xxTxStartup (struct ifnet * pDrvCtrl);
The 4.4 BSD version expects a pointer to a driver control structure. This change
eases the burden on the startup routine. Instead of having to find its own driver
control structure, it receives a pointer to a driver control structure as input.
If the driver uses netJobAdd( ) to schedule the transmit startup routine for
task-level execution, edit the netJobAdd( ) call to pass in a DRV_CTRL structure
pointer instead of a unit number.
G.2.3 Changes in Receiving Packets
Under 4.3 BSD, the driver calls do_protocol_with_type( ). For example:
do_protocol_with_type (etherType, pMbuf, &pDrvCtrl->idr, len);
This call expects an etherType (which the driver had to discover previously), a
pointer to an mbuf containing the packet data, the Interface Data Record, and the
length of the data.
Under 4.4 BSD, replace the call above with a call to do_protocol( ). For example:
do_protocol (pEh, pMbuf, &pDrvCtrl->idr, len);
The first parameter expects a pointer to the very beginning of the packet (including
the link level header). All the other parameters remain the same. The driver no
longer needs to figure out the etherType for the protocol.
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