Re: [PATCH v11 8/9] arm64: dts: qcom: ipq9574: Add LDO regulator node

From: Varadarajan Narayanan
Date: Wed May 10 2023 - 06:23:13 EST


On Tue, May 09, 2023 at 04:08:59PM +0300, Dmitry Baryshkov wrote:
> On Tue, 9 May 2023 at 14:56, Varadarajan Narayanan
> <quic_varada@xxxxxxxxxxx> wrote:
> >
> > Add LDO regulator node
> >
> > Signed-off-by: Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> > ---
> > Changes in v10:
> > - Add LDO regulator node
> > ---
> > arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts | 7 +++++++
> > 1 file changed, 7 insertions(+)
>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
>
> Minor question below:
>
> >
> > diff --git a/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts b/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
> > index bdc1434..1f5d14f 100644
> > --- a/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
> > +++ b/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
> > @@ -60,6 +60,13 @@
> > regulator-min-microvolt = <725000>;
> > regulator-max-microvolt = <1075000>;
> > };
> > +
> > + mp5496_l2: l2 {
> > + regulator-min-microvolt = <1800000>;
> > + regulator-max-microvolt = <1800000>;
> > + regulator-boot-on;
> > + regulator-always-on;
>
> This usually points out that there are other users which are not yet
> enabled/properly specified. What users are there for this supply which
> demand it to be always on?

The 1.8v rail is used by PCIe PHY, PLL for Ethernet SerDes
interface and PLLs that generate SoC clocks. The voting for this
rail is managed by the RPM f/w.

Thanks
Varada

> > + };
> > };
> > };
> >
> > --
> > 2.7.4
> >
>
>
> --
> With best wishes
> Dmitry