Re: [PATCH V2 03/15] arm64: dts: imx8mp-evk: fix BUCK/LDO voltage

[Peng Fan <peng.fan@xxxxxxxxxxx>]

On 10/28/2022 10:53 PM, Marco Felsch wrote:
> On 22-10-24, Peng Fan (OSS) wrote:
> > From: Peng Fan <peng.fan@xxxxxxx>
> >
> > Per PCA9450C datasheet, the voltage range as below:
> > BUCK1 0.6 - 2.1875
> > BUCK2 0.6 - 2.1875
> > BUCK4 0.6 - 3.4
> > BUCK5 0.6 - 3.4
> > BUCK6 0.6 - 3.4
> >
> > LDO1 1.6-1.9, 3.0-3.3
> > LDO2 0.8 – 1.15
> > LDO3 0.8 - 3.3
> > LDO4 0.8 - 3.3
> > LDO5 1.8 - 3.3
> >
> > Currently we set the board voltage range same as PMIC regulator
> > range.
>
> We did not therefore you aligned it. Also are you sure that this will
> not damage the boards since you're lowering the min-voltage and raising
> the max. voltage? According the schematic, BUCK1 is for VDD_SOC which is
> min. 0.805V and max. 1.0V. After you're change someone could set it to
> 2.1875V. Same applies to BUCK2 which is for VDD_ARM and should be within
> min. 0.805V and max. 1.05V.

You are right. But I think DVFS already limit it.

I am not sure very sure, let me drop this patch for now. I need confirm
with HW team.

Thanks,
Peng.

> Regards,
>    Marco
>
> > Also add LDO[2,4] in this patch
> >
> > Fixes: 5497bc2a2bff ("arm64: dts: imx8mp-evk: Add PMIC device")
> > Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> > ---
> >   arch/arm64/boot/dts/freescale/imx8mp-evk.dts | 44 +++++++++++++-------
> >   1 file changed, 30 insertions(+), 14 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mp-evk.dts b/arch/arm64/boot/dts/freescale/imx8mp-evk.dts
> > index b4c1ef2559f2..a4cddc5a8620 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mp-evk.dts
> > +++ b/arch/arm64/boot/dts/freescale/imx8mp-evk.dts
> > @@ -248,8 +248,8 @@ pmic@25 {
> >   		regulators {
> >   			BUCK1 {
> >   				regulator-name = "BUCK1";
> > -				regulator-min-microvolt = <720000>;
> > -				regulator-max-microvolt = <1000000>;
> > +				regulator-min-microvolt = <600000>;
> > +				regulator-max-microvolt = <2187500>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   				regulator-ramp-delay = <3125>;
> > @@ -257,8 +257,8 @@ BUCK1 {
> >   
> >   			reg_arm: BUCK2 {
> >   				regulator-name = "BUCK2";
> > -				regulator-min-microvolt = <720000>;
> > -				regulator-max-microvolt = <1025000>;
> > +				regulator-min-microvolt = <600000>;
> > +				regulator-max-microvolt = <2187500>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   				regulator-ramp-delay = <3125>;
> > @@ -268,40 +268,56 @@ reg_arm: BUCK2 {
> >   
> >   			BUCK4 {
> >   				regulator-name = "BUCK4";
> > -				regulator-min-microvolt = <3000000>;
> > -				regulator-max-microvolt = <3600000>;
> > +				regulator-min-microvolt = <600000>;
> > +				regulator-max-microvolt = <3400000>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   			};
> >   
> >   			BUCK5 {
> >   				regulator-name = "BUCK5";
> > -				regulator-min-microvolt = <1650000>;
> > -				regulator-max-microvolt = <1950000>;
> > +				regulator-min-microvolt = <600000>;
> > +				regulator-max-microvolt = <3400000>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   			};
> >   
> >   			BUCK6 {
> >   				regulator-name = "BUCK6";
> > -				regulator-min-microvolt = <1045000>;
> > -				regulator-max-microvolt = <1155000>;
> > +				regulator-min-microvolt = <600000>;
> > +				regulator-max-microvolt = <3400000>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   			};
> >   
> >   			LDO1 {
> >   				regulator-name = "LDO1";
> > -				regulator-min-microvolt = <1650000>;
> > -				regulator-max-microvolt = <1950000>;
> > +				regulator-min-microvolt = <1600000>;
> > +				regulator-max-microvolt = <3300000>;
> > +				regulator-boot-on;
> > +				regulator-always-on;
> > +			};
> > +
> > +			LDO2 {
> > +				regulator-name = "LDO2";
> > +				regulator-min-microvolt = <800000>;
> > +				regulator-max-microvolt = <1150000>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   			};
> >   
> >   			LDO3 {
> >   				regulator-name = "LDO3";
> > -				regulator-min-microvolt = <1710000>;
> > -				regulator-max-microvolt = <1890000>;
> > +				regulator-min-microvolt = <800000>;
> > +				regulator-max-microvolt = <3300000>;
> > +				regulator-boot-on;
> > +				regulator-always-on;
> > +			};
> > +
> > +			ldo4: LDO4 {
> > +				regulator-name = "LDO4";
> > +				regulator-min-microvolt = <800000>;
> > +				regulator-max-microvolt = <3300000>;
> >   				regulator-boot-on;
> >   				regulator-always-on;
> >   			};
> > --
> > 2.37.1