Subject: Re: Multiple boards at same interrupt?
To: Rob Healey <>
From: Michael L. Hitch <>
List: amiga-dev
Date: 04/22/1995 10:49:42
On Apr 22, 11:27am, Rob Healey wrote:
> 	interrupt can be handled at the same time, i.e. 1+N Lance
> 	ethernet cards? The older le driver stomped on multiple cards.
> 	When was the change put in and does it work OK? I was just
> 	settling down to add Multicast to the le driver when I
> 	noticed an #if 0 in the config routine.

  The original if_le.c interrupt routine was written to handle a single
card with the unit number passed to the interrupt routine. It should
have worked, if there was a call to the interrupt routine for each
configured board [which I don't think was ever in the interrupt code in

  I changed all the interrupt routines when I finally added the isr

> 	Also, it would appear that the ethernet card is in the
> 	isr chain before the internal SCSI controller on a 3000. Would
> 	this have any impact in SCSI vs le wars? It looks like other
> 	SCSI controllers are at 2 as well so does that mean the ethernet
> 	cards will always be processed before the SCSI controllers? Is
> 	this a performance concern? Is there a way to manually force

  It means that the Ethernet cards would be check for an interrupt
before the A3000 SCSI.  Not all SCSI adapters interrupt at level 2 [my
PPI Zeus uses 6, and I think the Magnum 40 SCSI does also.]

  I'm not sure how much the Ethernet interfaces would impact the SCSI.
If you had enough Ethernet boards, and enough Ethernet traffic, then it
might be possible to severley impact the SCSI adapter.  When I was doing
the isr chains, I wondered if a prioritized chain would be needed, but I
didn't think so at the time.

> 	the config order of devices so the SCSI controller would be
> 	configured before the other devices? It appears that a SCSI
> 	controller will always be the last thing to config from the
> 	kernel boot output I've seen.

  Most of my SCSI adapters configure before other Zorro boards.  All
Zorro boards are configured in order they appear in the ConfigDev chain,
which should be the order they appear in the Zorro bus slots.  Most of
my SCSI adapters are builtin to the accelerator cards and are configured
by expansion.library first.

  The A3000 SCSI does not have a ConfigDev entry, and it's currently
configured after the zbus configuration.  You could move that call (in
amiga/autoconf.c) to configure before the zbus configuration.


Michael L. Hitch			INTERNET:
Computer Consultant
Office of Systems and Computing Services
Montana State University	Bozeman, MT	USA