Re: [PATCH 2/2] interconnect: qcom: qcm2290: Enable sync state

From: Konrad Dybcio
Date: Fri Jul 21 2023 - 08:03:49 EST


On 20.07.2023 21:52, Stephan Gerhold wrote:
> On Thu, Jul 20, 2023 at 08:24:01PM +0200, Konrad Dybcio wrote:
>> Very surprisingly, qcm2290 does not seem to require any interface
>> clocks.
>
> What does this mean exactly? The interconnect .sync_state() is
> responsible to drop the initial maximum bandwidth votes, with the
> assumption that all active devices have voted for the bandwidth they
> need. How does this relate to "requiring interface clocks"?
If it required such clocks to be present, sync_state could not
complete, as trying to access some nodes would crash the platform
due to unclocked access.

>
>> It's therefore safe to enable sync_state to park unused devices.
>> Do so.
>
> Doesn't this make everything painfully slow? There are no interconnect
> consumers at all in qcm2290.dtsi. I would expect that all bandwidths
> end up at minimum.
There are no interconnect providers defined in qcm2290.dtsi.

Konrad