On 27 April 2016 at 16:04, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> Hi Ulf,
>
> On Wed, Apr 27, 2016 at 3:59 PM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
>> On 26 April 2016 at 09:09, Geert Uytterhoeven <geert+renesas@xxxxxxxxx> wrote:
>>> As a pure Clock Domain does not have the concept of powering the domain
>>> itself, the CPG/MSTP driver does not provide power_off() and power_on()
>>> callbacks.
>>> However, the genpd core may still perform a dummy power down, causing
>>> /sys/kernel/debug/pm_genpd/pm_genpd_summary to report the domain's
>>> status being "off-0".
>>>
>>> Use the always-on governor to make sure the domain is never powered
>>> down, and always shows up as "on" in pm_genpd_summary.
>>
>> Hmm.
>>
>> Hypothetically, what if the clock domain would be a subdomain, where
>> its master is able to power down? Using the always on governor would
>> prevent the master from power off as well.
>
> That's correct. However, on R-Mobile/R-Car SoCs, this is not the case, so it
> doesn't matter here.
>
>> I am wondering whether we should introduce some similar as
>> pm_runtime_no_callbacks() but for the generic PM domain instead.
>>
>> What do you think?
>
> In my case, the domain is not managed by its parent, to there's no such
> analogy.
Ok, fair enough.
This looks good to me!
Kind regards
Uffe
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds
