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

[Robert Marko]

On Wed, 25 Oct 2023 at 10:42, Kathiravan Thirumoorthy
<quic_kathirav@xxxxxxxxxxx> wrote:
>
>
>
> On 10/21/2023 5:27 PM, Robert Marko wrote:
> > 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.
>
>
> Could you please explain the issue which you are facing? Based on quick
> look at the HW documentation, seems there is no difference between
> IPQ8074 and IPQ6018 GDSC-s.

Thanks for checking, it seems I hit a buggy kernel version last time I tried to
convert the driver to use proper GDSC-s and now it seems to work fine,
I will send patches to add GDSC-s.

Regards,
Robert
>
> Thanks,