On 20.01.2016 18:52, Sriram V wrote: > Hi Krzyszof, > > > > On Mon, Jan 11, 2016 at 7:51 AM, Krzysztof Kozlowski > <k.kozlowski@xxxxxxxxxxx> wrote: >> On 11.01.2016 10:48, Sriram V wrote: >>> Hi Krzystof, >>> >>> >>> >>> On Mon, Jan 11, 2016 at 4:57 AM, Krzysztof Kozlowski >>> <k.kozlowski@xxxxxxxxxxx> wrote: >>>> 2016-01-10 22:49 GMT+09:00 Sriram V <vshrirama@xxxxxxxxx>: >>>>> Hi Krzysztof, >>>>> >>>>> I see that in pm_genpd_sumarry, the domains are off. However, i still >>>>> see the clocks are on. >>>>> For example; isp and cam is turned off in pm_genpd_summary, however >>>>> cam clocks are still on. >>>>> >>>>> Should'nt the clocks be turned off first and then the domain. >>>> >>>> No, the clocks in clock hierarchy are usually not disabled as a part >>>> of domain power off. However respective drivers attached to a power >>>> domain, when entering runtime suspend, should disable these clocks. >>>> >>> >>> That is true, runtime suspend framework should disable the clocks. >>> Hence, my question is if the clocks are active, Will disabling the >>> domain take effect? Because when i print the status - they show that >>> the domain is OFF. >> >> Yes, the domain will be disabled. >> >>> >>> On my system, what i see is camera clocks are active, But the domain >>> is OFF. Hence, i am not sure if camera subsystem is consuming power or >>> not since clocks are on. >>> >>> >From my understanding, the domain status should not indicate OFF if >>> any clocks are still on. >> >> Clocks and power domains in Linux are (mostly) independent subsystems so >> the domain will be disabled even though some clocks are active. Some >> clocks may be even missing in Linux (not defined) - it doesn't matter... >> >> It doesn't matter except in all the cases when this is a bug. :) The >> clocks should be disabled and some muxes reparented to oscclk. One of >> the cases we had was hang on reading clk_summary when power domain is off. >> > > Thanks for your pointers. > > When i boot the kernel, I see that the following domains are currently > on. I see that the following domains are currently on, Linux does not > know about these domains and they are permanently on. > > pd-fsys, pd-psgen, pd-peric, pd-wcore > > Is there a way of finding out if these can be shut off. i dont think > if clocks for the IP's serviced by these domains and the domain itself > is correctly tied-in in runtime-pm. As these domains are always on. The datasheet/reference manual in the "Local power control" describes conditions whether they could be disabled or not. It also documents what is required to power off them. > > Also, what kernel are you using? Usually mainline and linux-next. In some of the projects I use different ones, e.g. these on tizen.org (https://review.tizen.org/git/?p=platform/kernel/linux-exynos.git;a=summary). Best regards, Krzysztof -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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