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Subject: RE: [PATCH] Add irq host and hwirq pair fields to output
	whenshowing interrupts.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Zhang Wei-r63237 <Wei.Zhang@freescale.com>
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> > Now, regarding the patch itself, printing the hw irq is not 
> > that useful
> > without some indication of which host it belongs to. Best is to add a
> > name() or something like that to the host ops.
> > 
> 
> Sure, can I use the PIC controller node full name from of_tree as the
> host name?

There is no 1:1 relationship between an OF node and an irq host. (There
is -most- of the time but I left the irq core on purpose more flexible,
hence the match() method. On some setups it makes sense to have multiple
HW PICs share a single domain number (for example on cell).

Thus I'd rather have a way for the host to give you that name, which in
turn can be the OF path if there is such a thing, or something else...

Best might be 4 columns:

<virq> <hwirq> <pic name> <host name>

(PIC name is the same as in /proc/interrupts).
 
> Do you prefer debugfs instead of /proc/interrupts?

Yes, at least for now. Maybe if we can convince ourselves that nothing
significant would break of changing /proc/interrupts, then we can add
stuffs to it, but I'd rather avoid.

Ben.