Re: [PATCH 3/3] clk: qcom: gcc-sc7280: Update the .pwrsts for usb gdsc

[Rajendra Nayak]

On 9/15/2022 2:53 AM, Matthias Kaehlcke wrote:
> On Wed, Sep 14, 2022 at 09:12:36AM +0200, Johan Hovold wrote:
> > On Thu, Sep 01, 2022 at 09:04:55AM -0700, Matthias Kaehlcke wrote:
> > > On Thu, Sep 01, 2022 at 03:47:56PM +0530, Rajendra Nayak wrote:
> > > > USB on sc7280 cannot support wakeups from low power states
> > > > if the GDSC is turned OFF. Update the .pwrsts for usb GDSC so it
> > > > only transitions to RET in low power.
> > > >
> > > > Signed-off-by: Rajendra Nayak <quic_rjendra@xxxxxxxxxxx>
> > >
> > > Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> > > Tested-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> >
> > Did you confirm that you actually hit the retention state?
>
> No, how would I do that?
>
> > IIUC, this series is equivalent to using ALWAYS_ON unless CX is actually
> > powered off during suspend.
>
> The count in /sys/kernel/debug/qcom_stats/cxsd increses with each suspend,
> however it also does that with the GDSC configured as ALWAYS_ON and with
> Rajendra's "arm64: dts: qcom: sc7280: Add required-opps for USB" [1], so

hmm, that's really not expected. With my above patch and with the GDSC as
ALWAYS_ON there is a cx vote in suspend preventing cxsd so the counter
should not go up.

> I guess that isn't the correct signal.
>
> https://patchwork.kernel.org/project/linux-arm-msm/patch/20220914053017.23617-1-quic_rjendra@xxxxxxxxxxx/