Re: [PATCH 3/3] arm64: dts: rk3399: Add init voltage for vdd_log

From: Markus Reichl
Date: Tue Nov 12 2019 - 06:06:55 EST


Dear Sore, Kever,

Am 12.11.19 um 11:19 schrieb Soeren Moch:
>
>
> On 12.11.19 11:02, Kever Yang wrote:
>> Markus,
>>
>>
>> On 2019/11/12 äå4:16, Markus Reichl wrote:
>>> Hi Kever,
>>>
>>> have a rk3399-roc-pc running mainline U-Boot and kernel and vdd_log is
>>> showing 1118 mV.
>>
>> The rk3399-roc-pc have the same vdd_log circuit in schematic, so it
>> should like the patch 1/3 of
>>
>> this patch set.
>>
>> I don't understand who is setting this value, maybe the default value
>> without pwm regulator enabled?
>>
>>> Is this a danger for the board?
>>> How to fix it?
>>
>> The best way is to set correct min/max microvolt of the
>> regulator(measure with PWM output low and high),
> I didn't look into the schematic of this board, but if it is similar to
> RockPro64, setting the pwm regulator to the max voltage of 1.7V will
> probably kill the rk3399 immediately. So I recommend not to do this...
>
It has to be set to 450mV - 1400mV to give 953mV.
I will come out with a patch that fixes this.

> Regards,
> Soeren
>>
>> (note that if no driver touch the regulator, the PWM is default
>> input, not output;)
>> to
>> and set a init-microvolt for U-Boot driver, and I think no kernel
>> driver touch this regulator now.
>>
>>
>> Thanks,
>>
>> - Kever
>>
>>> Btw. vin-supply for this pwm-regulator is ignored and I could not
>>> find it
>>> in bindings doc.
>>>
>>> GruÃ,
>>
>>
>
>
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip@xxxxxxxxxxxxxxxxxxx
> http://lists.infradead.org/mailman/listinfo/linux-rockchip
>

GruÃ,
--
Markus Reichl