Re: [PATCH] pci: change msi-x vector to 32bit

From: H. Peter Anvin
Date: Mon Aug 18 2008 - 18:14:45 EST


Alan Cox wrote:
I completely agree that irq number 99.9% of the time should be a completely
abstract token.
Sure, although one nice reason for doing the abstraction first is that
it stops people imposing fragile numbering schemes on irq ...

On a lot of embedded devices IRQ numbers are not abstract and not
fragile. I'm all for abstracting out interrupts nicely but it isn't just
the legacy PC cases to consider - a lot of embedded is at least as
defined, rigid and meaningfully numbered as ISA.


Note that James said:

Sure, but you have 16 (or whatever) legacy interrupts. You still call
them 1-16 (or ISA-1 through ISA-16). By the time we reach this stage,
we're essentially doing string table lookups for the interrupts, so
there's no need to pre-allocate them (except as a possible arch
implementation detail).

I think the point is that if we're going to have a meaningful name, it should be a string, so we can impose whatever naming scheme makes sense for the platform. Even on embedded platforms it may mean that the flat number scheme isn't what makes sense.

-hpa
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