Re: [PATCH 8/9] ARM: dts: sun7i: bananapi-m1-plus: Add PMIC regulators and OPPs for cpufreq

[Chen-Yu Tsai <wens-jdAy2FN1RRM@public.gmane.org>]

Hi,

On Sat, Jul 9, 2016 at 4:18 PM, Maxime Ripard
<maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
> Hi,
>
> On Wed, Jul 06, 2016 at 05:10:49PM +0800, Chen-Yu Tsai wrote:
>> The Bananapi M1+, like other Allwinner A20 based boards, uses the AXP209
>> PMIC to supply its power. The vendor FEX file's DVFS table suggests the
>> board's CPU power rail has a voltage drop of 25 ~ 50 mV.
>>
>> Add the PMIC regulator nodes and copy the DVFS table from the FEX file.
>>
>> Signed-off-by: Chen-Yu Tsai <wens-jdAy2FN1RRM@public.gmane.org>
>> ---
>>  arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts | 48 ++++++++++++++++++++++--
>>  1 file changed, 44 insertions(+), 4 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts b/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts
>> index ba5bca0fe997..7bb418bd1b6e 100644
>> --- a/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts
>> +++ b/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts
>> @@ -105,6 +105,22 @@
>>       status = "okay";
>>  };
>>
>> +&cpu0 {
>> +     cpu-supply = <&reg_dcdc2>;
>> +
>> +     /* The custom DVFS table suggests a voltage drop of 25 ~ 50 mV */
>> +     operating-points = <
>> +             /* kHz    uV */
>> +             1080000 1450000
>> +             912000  1425000
>> +             864000  1350000
>> +             720000  1250000
>> +             528000  1150000
>> +             312000  1100000
>> +             144000  1050000
>> +             >;
>> +};
>> +
>
> We've always tried to not use all the non-sense OPPs coming from the
> FEX files. Have you experienced any issues with the default ones?

I'll find some time to run a stress test on it.

> The other patches have been queued either for 4.8 as fixes, or 4.9.

Thanks!

ChenYu

>
> Thanks!
> Maxime
>
> --
> Maxime Ripard, Free Electrons
> Embedded Linux and Kernel engineering
> http://free-electrons.com