Re: [PATCH v5 09/18] arm64: dts: qcom: qrb5165-rb5: model the PMU of the QCA6391

Dmitry Baryshkov
2024-02-20T18:12:05Z

On Tue, 20 Feb 2024 at 19:53, Bartosz Golaszewski <brgl@bgdev.pl> wrote:
>
> On Tue, Feb 20, 2024 at 5:30 PM Dmitry Baryshkov
> <dmitry.baryshkov@linaro.org> wrote:
> >
> > On Tue, 20 Feb 2024 at 13:16, Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > >
> > > On Mon, Feb 19, 2024 at 8:59 PM Mark Brown <broonie@kernel.org> wrote:
> > > >
> > > > On Mon, Feb 19, 2024 at 07:48:20PM +0100, Bartosz Golaszewski wrote:
> > > > > On Mon, Feb 19, 2024 at 7:03 PM Mark Brown <broonie@kernel.org> wrote:
> > > > > > On Fri, Feb 16, 2024 at 09:32:06PM +0100, Bartosz Golaszewski wrote:
> > > >
> > > > > > > + vreg_pmu_aon_0p59: ldo1 {
> > > > > > > + regulator-name = "vreg_pmu_aon_0p59";
> > > > > > > + regulator-min-microvolt = <540000>;
> > > > > > > + regulator-max-microvolt = <840000>;
> > > > > > > + };
> > > >
> > > > > > That's a *very* wide voltage range for a supply that's got a name ending
> > >
> > > Because it's an error, it should have been 640000. Thanks for spotting it.
> >
> > According to the datasheet, VDD08_PMU_AON_O goes up to 0.85V then down
> > to 0.59V, which is the working voltage.
> >
>
> Hmm indeed this is what figure 3.4 says but table 3-2 says the maximum is 0.64V.
>
> > VDD08_PMU_RFA_CMN is normally at 0.8V, but goes to 0.4V during sleep.
> >
>
> Again figure 3.4 and table 3-2 disagree unless I'm missing something.

I suspect that the table you have mentioned provides normal working
conditions for the PMU, while power-up and sleep might be outside of
'normal' conditions.

I suppose that these outputs are underspecified in the datasheet. I
think we can omit the values here.

--
With best wishes
Dmitry