Subject: Re: IRQ and DRQ autoconfiguration
To: Charles M. Hannum <mycroft@duality.gnu.ai.mit.edu>
From: None <Mark_Weaver@brown.edu>
List: current-users
Date: 07/30/1994 02:27:16
"Charles M. Hannum" <mycroft@duality.gnu.ai.mit.edu> writes:
> I've just enabled some old code I had written in the aha, ahb, bt, and
> uha drivers, to use the IRQ and DRQ read off the board at boot time,
> rather than statically configuring the info into the kernel.
Cool, I'll test it tonight on my Ultrastor 34F.
> I also fixed some bogons related to how DMA channels were configured,
> that have been around since Julian.
This reminds me of something I was always curious about. The
Ultrastor 14F uses DMA to transfer the data, whereas the 34F is a
bus-mastering VLB card that does the transfer on its own. Yet,
long ago when I was looking through ultra14f.c, I couldn't find
any difference in how the two cards were treated. In fact, the
only change that was necessary to get the 34f working way back
before NetBSD existed was to increase a couple of timeouts.
My question is: where does the uha code call the dma code to get
it to transfer the data, and is this code somehow turned off for
the 34f? It should be. I'm very unfamiliar with the Intel hardware
architecture, so please forgive me if I'm asking a stupid question.
Mark
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Email: Mark_Weaver@brown.edu | Brown University
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