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    SubjectRe: Enable arm_global_timer for Zynq brakes boot
    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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