Messages in this thread | | | From | Peng Fan <> | Subject | RE: [PATCH V5 07/12] arm64: dts: imx8mn-evk: update vdd_soc dvs voltage | Date | Wed, 16 Nov 2022 15:47:01 +0000 |
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> Subject: Re: [PATCH V5 07/12] arm64: dts: imx8mn-evk: update vdd_soc dvs > voltage > > On 22-11-16, Peng Fan wrote: > > > Subject: Re: [PATCH V5 07/12] arm64: dts: imx8mn-evk: update vdd_soc > > > dvs voltage > > > > > > Hi Peng, > > > > > > On 22-11-15, Peng Fan (OSS) wrote: > > > > From: Peng Fan <peng.fan@nxp.com> > > > > > > > > Per schematic, BUCK1 is for VDD_SOC&DRAM&PU_0V9. The > > > > nxp,dvs-run-voltage and nxp,dvs-standby-voltage need set for > > > > BUCK1, not > > > BUCK2. > > > > BUCK2 is for A53, which is handled by DVFS, so no need dvs property. > > > > > > > > Signed-off-by: Peng Fan <peng.fan@nxp.com> > > > > --- > > > > arch/arm64/boot/dts/freescale/imx8mn-evk.dts | 4 ++-- > > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/arch/arm64/boot/dts/freescale/imx8mn-evk.dts > > > > b/arch/arm64/boot/dts/freescale/imx8mn-evk.dts > > > > index 4eb467df5ba7..a5a7d74ec1d5 100644 > > > > --- a/arch/arm64/boot/dts/freescale/imx8mn-evk.dts > > > > +++ b/arch/arm64/boot/dts/freescale/imx8mn-evk.dts > > > > @@ -47,6 +47,8 @@ buck1: BUCK1{ > > > > regulator-boot-on; > > > > regulator-always-on; > > > > regulator-ramp-delay = <3125>; > > > > + nxp,dvs-run-voltage = <950000>; > > > > > > One last question on this. According the schematic the max should be > > > 0.88/0.945V and you are going to set it to 0.950V. > > > > No, my schematic shows the TYP voltage is 0.85/0.95V. > > I have the Rev.A2 i.MX8MNano DDR4 SoM schematic and TYP is listed as > 0.8/0.9V. Is this different for different ram configurations? [Peng Fan]
It maybe DDR4 board support 2400MTS, LPDDR4 board support 3200MTS, but I am not sure.
Regards, Peng.
Sorry for asking > but the i.MX8MNano LPDDR4 schematic is not available. > > > > According the driver the nxp,dvs-run-voltage is just the same as the > > > normal regulator voltage. So I would suggest to just use the > > > nxp,dvs-standby- voltage property to enable the DVS feature since > > > the run voltage is already handled by the > > > regulator-min-microvolt/regulator-max-microvolt. So it would be just: > > It should be fine to not set nxp,dvs-run-voltage, because bootloader > > already set that. > > Okay, so leave the voltage as it is right now and just add the nxp,dvs- > standby-voltage seems fine :) > > Regards, > Marco > > > > > Thanks, > > Peng. > > > > > > > + nxp,dvs-standby-voltage = <750000>; > > > > > > Regards, > > > Marco > > > > > > > }; > > > > > > > > buck2: BUCK2 { > > > > @@ -56,8 +58,6 @@ buck2: BUCK2 { > > > > regulator-boot-on; > > > > regulator-always-on; > > > > regulator-ramp-delay = <3125>; > > > > - nxp,dvs-run-voltage = <950000>; > > > > - nxp,dvs-standby-voltage = <850000>; > > > > }; > > > > > > > > buck4: BUCK4{ > > > > -- > > > > 2.37.1 > > > > > > > > > > > > > >
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