Re: Two different interrupt-parents

On Mon, Apr 16, 2012 at 09:55:09AM -0400, jonsmirl-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org wrote:

On Mon, Apr 16, 2012 at 12:53 AM, David Gibson
[off-list ref] wrote:

quoted

On Mon, Apr 16, 2012 at 04:14:25AM +0000, Sethi Varun-B16395 wrote:

quoted

You can use a 4 cell interrupt specifier (we use that in case of embedded power architecture platforms)
- First cell corresponds to one of the four cascade lines (coming from the cascaded pic)
- Second cell provides the interrupt sense information
- Third one tells the interrupt subtype (in your case should be the cascade power interrupt type)
- Fourth cell communicates the interrupt number corresponding to the cascaded pic.

There would be a single interrupt parent, which is the system interrupt controller. You would have
to translate the four cell interrupt specifier and also add cascaded interrupt handling
for the shared interrupt line.

No, don't do that.

Use the interrupt-map technique described in the thread that got
linked earlier.

If interrupts had syntax like GPIOs this problem wouldn't exist.

Yes, but the interrupt syntax has existed since forever, so it's not
worth creating a new incompatible one which we'd need to teach all the
clients about, when a perfectl good workaround like the interrupt-map
method exists.

-- 
David Gibson			| I'll have my music baroque, and my code
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				| _way_ _around_!
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