Bamboo PCI interrupt issues

Segher Boessenkool segher at
Wed Mar 5 07:39:29 EST 2008

>> Using '8' is correct. PCI interrupts are *always* level sensitive and
>> active
>> low.
> Unless you use one of those strange bridges that stick not gates on the
> PCI IRQ inputs :-) But I don't think that's the case on the 440EP.

More generally, the target interrupt descriptors (sense values, in
particular) in a device tree interrupt map describe the interrupts as
seen on the target interrupt controller, *not* as seen on this (source)
interrupt domain.  This should be obvious, but since the source 
descriptor for PCI doesn't have a sense value (it's always level low,
after all), it can be confusing.  Well, interrupts always are confusing 


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