On Mon, Jul 17, 2017 at 11:40 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: > On Mon, 17 Jul 2017, dbasehore . wrote: >> On Mon, Jul 17, 2017 at 6:33 PM, Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote: >> I could make a patch to try it out. I would probably add a flag to rtc >> timers to indicate whether it wakes the system (default true). We >> would have to add a sync with the rtc irq and the rtc irqwork. I would >> probably add a rtc_timer_sync function that would flush the rtc irq >> and flush the irqwork. I would call this after the freeze_ops sync >> function since the sci irq needs to finish before syncing with the rtc >> irq. Also, pm_wakeup_irq seems racy with the current implementation of >> s2idle_loop since the RTC irq could be mistakenly set as pm_wakeup_irq >> when something else actually triggered the full wakeup. Fortunately, I >> don't think pm_wakeup_irq is used for anything except debugging, but >> we might change that. > > There is another option which you might consider. We can reserve one of the > HPET comparators for that purpose and have a special interrupt handler for > it. Checking the HPET for expiry from the low level code should be trivial. > Does that handle setting up new timers properly or does the timer sync code still need to be written? > Thanks, > > tglx > >
