Re: [PATCH 02/12] soc: qcom: aoss: Drop power domain support

Bjorn Andersson
2021-05-28T04:05:32Z

On Tue 27 Apr 01:25 CDT 2021, Sibi Sankar wrote:

> On 2021-04-18 07:31, Stephen Boyd wrote:
> > Quoting Sibi Sankar (2021-04-16 05:03:48)
> > > The load state resources are expected to follow the life cycle of the
> > > remote processor it tracks. However, modeling load state resources as
> > > power-domains result in them getting turned off during system suspend
> > > and thereby falling out of sync with the remote processors that are
> > > still
> > > on. Fix this by replacing load state resource control through the
> > > generic
> > > qmp message send interface instead.
> > >
> > > Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
> > > ---
> >
> > Is it possible to keep this code around for a cycle so that there isn't
> > the chance that someone is using the deprecated DT bindings with a new
> > kernel? I worry that ripping the code out will cause them angst.
>
> deprecated bindings with a newer kernel
> shouldn't cause any problems since it is
> the driver changes that make AOSS PD
> mandatory or not. So the newer kernel will
> just use qmp_send and leave the PD unused.
>

Maybe I'm missing something in your argument here, but I see two issues:
* The changes here requires that the new qcom,qmp property is defined,
or the qcom_qmp_get() will be unable to find the qmp instance.
* Between patch 2 and 5 there's no load_state handling.

Perhaps we can carry the power-domain handling as a fallback i
qcom_qmp_get() fails, for a few releases?

Other than the ordering and backwards compatibility issue I think this
looks good. So can you please respin this based on the later revision of
the qmp patch? (And fix Rob's request on the commit message)

https://lore.kernel.org/linux-arm-msm/1620320818-2206-2-git-send-email-deesin@codeaurora.org/

Regards,
Bjorn

> > Certainly we have to keep the code in place until DT is updated, so this
> > patch should come last?
>
> sure I don't mind, as long as it simplifies
> the merge process.
>
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