On Fri, 9 Jul 2021 at 13:39, Dmitry Baryshkov
[off-list ref] wrote:

Hi,

On Fri, 9 Jul 2021 at 11:25, Ulf Hansson [off-list ref] wrote:

quoted

On Fri, 9 Jul 2021 at 06:32, Dmitry Baryshkov
[off-list ref] wrote:

quoted

Registers for some genpds can be located in the SoC area, powered up by
another power domain. To enabled access to those registers, respective
domain should be turned on.

This patch adds basic infrastructure to the genpd code to allow
implementing drivers for such genpd. PM domain can provide the parent
device through the genpd->dev.parent pointer. If its provided at the
pm_genpd_init() call time and if it is pm-enabled, genpd power_on and
power_off operations will call pm_runtime_get_sync() before powering up
the domain and pm_runtime_put_sync() after powering it down.

Signed-off-by: Dmitry Baryshkov <redacted>

Hi Dmitry,

Using runtime PM for the genpd provider device, is not the correct
approach. If the provider domain needs another domain to be powered on
to work correctly, that per definition means that it has a parent
domain.

I suggest you try to build the correct PM domain topology, via using
pm_genpd_add_subdomain() or of_genpd_add_subdomain(), then genpd will
manages the power on/off for parent/child domain internally.

Indeed, this patch seems redundant now, with the
pm_genpd_add_subdomain call in place.
Would you like me to resend a v3 just dropping this patch?

Yes, $subject patch isn't the way to go.

Let's continue discussing things on patch3/7 to conclude on the way forward.

[...]

Kind regards
Uffe