Messages in this thread | | | Date | Tue, 30 Jul 2013 10:47:15 +0200 | From | Daniel Lezcano <> | Subject | Re: Enable arm_global_timer for Zynq brakes boot |
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On 07/30/2013 02:03 AM, Sören Brinkmann wrote: > Hi Daniel, > > On Mon, Jul 29, 2013 at 02:51:49PM +0200, Daniel Lezcano wrote: > (snip) >> >> the CPUIDLE_FLAG_TIMER_STOP flag tells the cpuidle framework the local >> timer will be stopped when entering to the idle state. In this case, the >> cpuidle framework will call clockevents_notify(ENTER) and switches to a >> broadcast timer and will call clockevents_notify(EXIT) when exiting the >> idle state, switching the local timer back in use. > > I've been thinking about this, trying to understand how this makes my > boot attempts on Zynq hang. IIUC, the wrongly provided TIMER_STOP flag > would make the timer core switch to a broadcast device even though it > wouldn't be necessary. But shouldn't it still work? It sounds like we do > something useless, but nothing wrong in a sense that it should result in > breakage. I guess I'm missing something obvious. This timer system will > always remain a mystery to me. > > Actually this more or less leads to the question: What is this > 'broadcast timer'. I guess that is some clockevent device which is > common to all cores? (that would be the cadence_ttc for Zynq). Is the > hang pointing to some issue with that driver?
If you look at the /proc/timer_list, which timer is used for broadcasting ?
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