Re: [PATCH] clk: qcom: gcc-ipq6018: add QUP6 I2C clock

From: Robert Marko
Date: Sat Oct 21 2023 - 07:57:34 EST


On Fri, 20 Oct 2023 at 08:40, Kathiravan Thirumoorthy
<quic_kathirav@xxxxxxxxxxx> wrote:
>
>
> On 10/19/2023 7:53 PM, Robert Marko wrote:
> > On Thu, 19 Oct 2023 at 08:46, Kathiravan Thirumoorthy
> > <quic_kathirav@xxxxxxxxxxx> wrote:
> >>
> >> On 10/19/2023 1:59 AM, Konrad Dybcio wrote:
> >>>
> >>> On 10/15/23 18:20, Robert Marko wrote:
> >>>> QUP6 I2C clock is listed in the dt bindings but it was never included in
> >>>> the GCC driver.
> >>>> So lets add support for it, its intentionally marked to never be
> >>>> disabled
> >>>> as its somehow affecting DVFS and if disabled it sometimes crashes the
> >>>> board.
> >>>>
> >>>> Signed-off-by: Robert Marko <robimarko@xxxxxxxxx>
> >>>> ---
> >>> Bjorn, would you be able to get an idea of what could be sitting
> >>> on that bus?
> >>>
> >>> Or maybe the IPQ folks could know?
> >>>
> >> Konrad / Robert,
> >>
> >> Similar to IPQ9574, RPM needs this clock to communicate with PMIC over
> >> I2C interface. Discussion happened here[1] is pretty much applicable to
> >> IPQ6018 as well. Based on previous experience, we may need to document
> >> the reason for CLK_IGNORE_UNUSED in driver as well. Nevertheless,
> >>
> >> Reviewed-by: Kathiravan Thirumoorthy <quic_kathirav@xxxxxxxxxxx>
> > Thanks for the explanation, it makes sense as I used to control the
> > MP5496 directly
> > via I2C.
> >
> > Is it possible to disable RPM so it doesn't conflict and just use the
> > full MP5496 driver instead?
> > I find the RPM quite limiting as there is no way to actually retrieve
> > the current-voltage.
>
>
> Robert, checked with the team and currently we don't have any option to
> disable the RPM as such.

Thanks for checking.

BTW, is there any information you could share on the USB GDSC-s?
I tried converting them to GDSC-s like IPQ8074 has, but it seems that
they have different features.
It would be great to use proper GSDC support instead of manually
setting bits during GCC probe.

Regards,
Robert
>
>
> >
> > Regards,
> > Robert
> >> [1]
> >> https://lore.kernel.org/linux-arm-msm/2852fc37-284f-6534-f163-45b37b153db1@xxxxxxxxxxx/
> >>
> >>
> >>> Konrad