Subject: Re: PCMCIA 3C589B on 1.3 alpha
To: Martin Husemann <>
From: Jason Thorpe <>
List: port-i386
Date: 12/01/1997 10:55:31
On Fri, 28 Nov 1997 07:28:28 +0100 (MET) 
 Martin Husemann <> wrote:

 > Why isn't this mask calculated at runtime? Or the mapping retried with another
 > irq if one fails?

Unfortunately, I know of no way to do this.  When you get an IRQ that
doesn't work, one of two things will happen:

	(a) Your machine will hang when the first interrupt comes in.

	(b) Your device will never get interrupts.

(a) is hard to recover from.  And (b) is hard to distinguish from e.g.
"nothing is happening, no, really".

There are some BIOS calls that one can make to "solve" some of the
problems people have mentioned here, i.e. getting a decent IRQ, getting
a decent I/O base, etc.  Unfortunately, it doens't appear as if there
is a protected-mode interface to these calls (like there is for APM),
which makes using them problematic.

Jason R. Thorpe                             
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