Maybe you can remove all these computations and set the flag en_core_tk_irqen for the driver ? That will be handled by the cpuidle framework, no ?
Same comment for the intel_idle driver.
Yeah, I thought about that, too. I was a little too afraid of touching the sched_clock_idle_wakeup_event() parameter that is tied to the measurement, but it seems to have been vestigial for some time now and other drivers also just set it 0. I will whip up another version of the patch (won't change the PPC further though, if this version works I would just leave it at that... thanks for testing, Deepthi).