On 08/12/2013 06:53 PM, Sören Brinkmann wrote: > On Mon, Aug 12, 2013 at 06:49:17PM +0200, Daniel Lezcano wrote: >> On 08/12/2013 06:32 PM, Sören Brinkmann wrote: >>> On Mon, Aug 12, 2013 at 09:20:19AM -0700, Stephen Boyd wrote: >>>> On 08/12/13 09:03, Sören Brinkmann wrote: >>>>> On Fri, Aug 09, 2013 at 10:27:57AM -0700, Stephen Boyd wrote: >>>>>> On 08/09, Daniel Lezcano wrote: >>>>>>> yes, but at least the broadcast mechanism should send an IPI to cpu0 to >>>>>>> wake it up, no ? As Stephen stated this kind of configuration should has >>>>>>> never been tested before so the tick broadcast code is not handling this >>>>>>> case properly IMHO. >>>>>>> >>>>>> If you have a per-cpu tick device that isn't suffering from >>>>>> FEAT_C3_STOP why wouldn't you use that for the tick versus a >>>>>> per-cpu tick device that has FEAT_C3_STOP? It sounds like there >>>>>> is a bug in the preference logic or you should boost the rating >>>>>> of the arm global timer above the twd. Does this patch help? It >>>>>> should make the arm global timer the tick device and whatever the >>>>>> cadence timer you have into the broadcast device. >>>>> I finally got to test your patch. Unfortunately, it makes the system >>>>> hang even earlier: >>>> >>>> Sorry it had a bug depending on the registration order. Can you try this >>>> one (tabs are probably spaces, sorry)? I will go read through this >>>> thread to see if we already covered the registration order. >>> >>> That did it! Booted straight into the system. >> >> Good news :) >> >>> The broadcast device is >>> the TTC instead of GT, now. >>> >>> Tick Device: mode: 1 >>> Broadcast device >>> Clock Event Device: ttc_clockevent >>> max_delta_ns: 1207932479 >>> min_delta_ns: 18432 >>> mult: 233015 >>> shift: 32 >>> mode: 1 >>> next_event: 9223372036854775807 nsecs >>> set_next_event: ttc_set_next_event >>> set_mode: ttc_set_mode >>> event_handler: tick_handle_oneshot_broadcast >>> retries: 0 >>> >>> tick_broadcast_mask: 00000000 >>> tick_broadcast_oneshot_mask: 00000000 >> >> At the first glance, the timer broadcast usage is not set, right ? Can >> you try with the cpuidle flag even if it is not needed ? > > It's actually present. I have a clean 3.11-rc3 and the only changes are > my patch to enable the GT and Stephen's fix. > The cpuidle stats show both idle states being used.
Ah, right. The tick_broadcast_mask is not set because the arm global timer has not the CLOCK_EVT_FEAT_C3STOP feature flag set. Thanks -- Daniel -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog -- 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/
