Having looked somewhat closer at the SCSI and se code, I've got a slightly
better idea of what's happening.  When I try to add IP to the adaptor
(ifconfig se0 inet 192.168.13.1), the command prompt doesn't come back.
I've traced the problem down to the SCSI code :

	the IP stack sends an ARP request for its address -
	the call sequence is -
		...
		ether_output()
		se_ifstart()
		scsi_scsipi_cmd()
		scsipi_execute_xs()
		ncr5380_scsi_cmd()
		run_main()
		scsi_main()
		information_transfer()
		handle_message()

This is where I think the problem is.  In ncr5380_scsi_cmd() (file
... src/sys/arch/atari/dev/ncr5380.c), there are the lines :

	run_main(xs->sc_link->adaptor_softc);
	if (xs->flags & SCSI_POLL|ITSDONE)
		return (COMPLETE);
	return (SUCESSFULLY_QUEUED);

Back in scsipi_execute_xs() (file ... src/sys/dev/scsipi/scsipi_base.c),
returning 'SUCESSFULLY_QUEUED' causes :

	case SUCESSFULLY_QUEUED:
		...
		tsleep (xs, PRIBIO + 1, "scsipi_cmd", 0);

causing ifconfig to sleep on wait channel 'scsipi_cmd'.  Unfortunately,
it never gets woken up, so I don't get the prompt back :(

The arp packet is sent out (seen with tcpdump), so I would (naively)
expect that the code would return 'COMPLETE' and not 'SUCESSFULLY_QUEUED'.
For it to return 'COMPLETE', 'ITSDONE' should be set (via finish_req()
called in handle_message() I assume), and I can't see why it isn't.  I
would guess that the adaptor has finished, but the code thinks it hasn't :(
Pointers greatly appreciated.  Alternatively, I shall wade through the
SCSI code with the debugger sometime tomorrow ...

J

PS.  This may be a stupid question, but why is there a separate Atari
version of the 5380 code?

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