On Wed, Jul 19, 2017 at 4:19 PM, Marc Zyngier [off-list ref] wrote:

On a slightly tangential subject, there is another aspect that I thought
of implementing for a while, but always ended up just relying on a quick
hack: forcing the injection of an actual interrupt. A number of
interrupt controllers have the ability to make an interrupt pending, for
it to be handled as if a device had actually triggered it.

This would be especially useful for a class of embedded systems that
are woken up from deep sleep by an asynchronous interrupt controller.

Usually GPIO(-ish) lines are armed and the system put to sleep, and
when it comes up, the information of what line woke it up is there in a
special register, but the actual (synchronous) interrupt line is no longer
asserted or edge triggered, so an interrupt need to be inserted.

Yours,
Linus Walleij