* Zwane Mwaikambo <[EMAIL PROTECTED]> [050204 09:54]: > On Fri, 4 Feb 2005, Tony Lindgren wrote: > > > * Zwane Mwaikambo <[EMAIL PROTECTED]> [050204 09:31]: > > > On Fri, 4 Feb 2005, Tony Lindgren wrote: > > > > > > > Yes, it's safer to keep the timer periodic, although it's > > > > used for oneshot purposes for the skips. If the timer interrupt > > > > got missed for some reason, the system would be able to recover when > > > > it's in periodic mode. > > > > > > > > And with some timers, we can do the reprogramming faster, as we just > > > > need to load the new value. > > > > > > > > I could not figure out how to disable the interrupts for PIT > > > > when local APIC is used and the ticks to skip is longer than PIT > > > > would allow. So I just changed the mode temporarily to disable it. > > > > > > > > Does anybody know if there's a way to stop PIT interrupts while > > > > keeping it in the periodic mode? > > > > > > disable_irq(0) ? > > > > Then the problem is that the CPU does not stay in sleep but wakes to > > the first PIT interrupt AFAIK. > > I do not understand, do you want to disable the PIT from interrupting the > processor and enable it interrupting at a later time?
Yes, that right. PIT max skip ticks = 54 and local APIC timer > 1000. PIT interrupt needs to be disabled to stay in sleep for over 54 ticks. But I think you're right, disable_irq(0) should do the trick :) Hmmm, we should be able to keep PIT irq disabled all the time when using local APIC timer. I'll play with it a bit. Tony - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
