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

From: Marco Felsch
Date: Fri Oct 28 2022 - 10:53:21 EST


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.

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
>
>
>