Re: [RFC PATCH v5 0/4] PM: domain: Support skiping disabling unused domains until sync state

From: Ulf Hansson
Date: Mon Apr 07 2025 - 12:26:08 EST


On Mon, 7 Apr 2025 at 16:13, Devarsh Thakkar
<devarsht@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hi Abel,
>
> On 21/06/23 20:10, Abel Vesa wrote:
>
> Thanks a lot for working on this.
>
> > This new approach drops the is_off change that was part of v4. That was
> > kind of beyond the scope of this patchset. This new approach changes the
> > boot_keep_on in such a way that we won't need any kind of new locking
> > for a PD. This involves using the patch [1] for adding dev_set_drv_sync_state
> > from Saravana for allowing the genpd core to set a default sync state
> > callback for a provider that doesn't register one by itself. While at it,
> > we can add another such API but this time to query a device's sync state.
> > Then, we filter out each power off request in such a way that if a boot
> > powered on power domain is not attached to its consumer device and
> > the provider has not state synced yet, the power off request is skipped.
> >
> > [1] https://lore.kernel.org/all/20210407034456.516204-2-saravanak@xxxxxxxxxx/
> >
> > No worth mentioning what changed since v4 as this version is almost
> > entirely reworked.
> >
> > Abel Vesa (3):
> > driver core: Add dev_is_drv_state_synced()
> > PM: domains: Ignore power off request for enabled unused domains
> > PM: domains: Add and set generic sync state callback
> >
> > Saravana Kannan (1):
> > driver core: Add dev_set_drv_sync_state()
> >
>
> Could you please share if you are planning to re-spin this series as
> non-RFC in near future ?
>
> We think that these patches would be useful to enable smooth display
> transition from boot-loader to kernel space, something which our team is
> working on, so just wanted to know your plans for this series.

I am working on it as we speak, but I need a few more days for
testing. You should expect something to hit LKML later this week or at
least early next week.

I will keep you posted!

Kind regards
Uffe

>
>
> Regards
> Devarsh
>
> > drivers/base/power/domain.c | 72 +++++++++++++++++++++++++++++++++++++
> > include/linux/device.h | 26 ++++++++++++++
> > include/linux/pm_domain.h | 4 +++
> > 3 files changed, 102 insertions(+)
> >
>