Hi Krzysztof, Are you saying that only power domains under "Local Power Control" can be attached to runtime PM and can be turned off? In that case, i dont see other domains such as peris, psgen, wcore in there, Hence these need to be always on? is my understanding correct? Thanks On Wed, Jan 20, 2016 at 3:42 PM, Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx> wrote: > 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 -- Regards, Sriram -- 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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