Multiple PCI devices on the same IRQ: kernel or driver?

Michael Ogg ogg@research.bell-labs.com
Mon Nov 30 15:22:12 1998


> I read through the mailing list archive and found that Bruce Benson also
> had this problem in December of 1997 with the same machine that I have (a
> gw2k P-5 133).  I exchanged email with Bruce and he stated that the
> driver is the source of the problem rather than the kernel.  He suggested
> that I try rearranging the cards on the bus, loading the necessary
> modules in different orders, or using different compiler switches when
> compiling the modules.

There's another solution that I've used successfully (albeit reluctantly):
you can "hard wire" a particular PCI slot to use a specific IRQ.  Many
(possibly all) BIOS allow you to do this.  The reluctance should be
obvious, and it kinda breaks the idea of Plug 'n Play.  But until PCI truly
is Plug 'n Play, what canya do?

The combination where I've done this successfully is an Adaptec 2940 plus
Kingston 21140, but I believe it should work for any IRQ assignment.

Mike

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