On Sat, Mar 31, 2012 at 7:00 AM, Ming Lei <tom.leiming@xxxxxxxxx> wrote: > On Fri, Mar 30, 2012 at 5:20 PM, Shilimkar, Santosh <santosh.shilimkar@xxxxxx> >> >>> After Ming Lie's comment, the point that I came to my mind was, >>> certainly there will be resolution difference between these two clocksources, >>> if gptimer2 is sourced from sys_ck (26Mhz). >>> >> GPTIMER2 with sysclock is not an option. GPTIMER is not in wakeup domain >> and when sysclock is cut, it stops. > > If neither CONFIG_PM or CONFIG_CPUIDLE is set, GPTIMER2 with sysclock > should be an option. > So it's a PM disable kernel and you will recompile it. > As I commented before, high resolution timer is very useful for trace, debug or > high frequency perf sample. Suppose you want to trace the running time of > one function, 32K counter can only give you a resolution of ~35us, which is > too coarse to work well. > Since you need to recompile the kernel, you can very much tweak the clocksource to use GPTIMER with sysl clock. Support for that is still in place. Regards Santosh -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
