Re: Interrupt Disable bit

[David Kahn <dmk@noho.eng.sun.com>]

>Sigh. Is this register mandatory? Sorry don't have PCI 2.3 handy.

>Not sure the gain's really worth it; sharing interrupts is never great, but
>this seems like a corner enough case not to have warranted a spec change.

I would respectfully disagree. It's a very useful feature from 
the reliability perspective and should have been there from day 1.
If there are problems with spurious interrupts, it's nearly
impossible for s/w to debug the problem and/or isolate the
device without this.

I believe the intent of this bit is that it is owned by the
'system' (eg: firmware or OS), and not the device driver.

MSI's will have a similar 'mask' bit per MSI being added via an ECN.

-David