Re: [PATCH v2 43/48] ARM: tegra: Add OPP tables and power domains to Tegra20 device-tree

From: Dmitry Osipenko
Date: Tue Dec 22 2020 - 14:25:18 EST


22.12.2020 08:47, Viresh Kumar пишет:
> On 17-12-20, 21:06, Dmitry Osipenko wrote:
>> diff --git a/arch/arm/boot/dts/tegra20-peripherals-opp.dtsi b/arch/arm/boot/dts/tegra20-peripherals-opp.dtsi
>> index b84afecea154..7e015cdfbc55 100644
>> --- a/arch/arm/boot/dts/tegra20-peripherals-opp.dtsi
>> +++ b/arch/arm/boot/dts/tegra20-peripherals-opp.dtsi
>> @@ -1,6 +1,46 @@
>> // SPDX-License-Identifier: GPL-2.0
>>
>> / {
>> + core_opp_table: core-power-domain-opp-table {
>> + compatible = "operating-points-v2";
>> + opp-shared;
>> +
>> + core_opp_950: opp@950000 {
>> + opp-microvolt = <950000 950000 1300000>;
>> + opp-level = <950000>;
>> + };
>
> I am not sure I fully understand this, why does it have both microvolt and level
> properties ?
>

The level is used by everything related to GENPD, while voltage is used
by the domain driver.

I think it's cleaner to separate the level from voltage, even though
they are set to the same values, which is done purely for convenience.
The 0,1,2,3 levels are meaningless in the context of this power domain,
while voltages make total sense.