Re: [PATCH v2 00/48] Introduce core voltage scaling for NVIDIA Tegra20/30 SoCs

From: Dmitry Osipenko
Date: Thu Jan 07 2021 - 14:40:19 EST

05.01.2021 20:11, Krzysztof Kozlowski пишет:
> On Thu, Dec 17, 2020 at 09:05:50PM +0300, Dmitry Osipenko wrote:
>> Introduce core voltage scaling for NVIDIA Tegra20/30 SoCs, which reduces
>> power consumption and heating of the Tegra chips. Tegra SoC has multiple
>> hardware units which belong to a core power domain of the SoC and share
>> the core voltage. The voltage must be selected in accordance to a minimum
>> requirement of every core hardware unit.
>> The minimum core voltage requirement depends on:
>> 1. Clock enable state of a hardware unit.
>> 2. Clock frequency.
>> 3. Unit's internal idling/active state.
>> This series is tested on Acer A500 (T20), AC100 (T20), Nexus 7 (T30),
>> Ouya (T30), TK1 (T124) and some others. I also added voltage scaling to
>> the Ventana (T20) and Cardhu (T30) boards which are tested by NVIDIA's CI
>> farm. Tegra30 is now couple degrees cooler on Nexus 7 and stays cool on
>> Ouya (instead of becoming burning hot) while system is idling. It should
>> be possible to improve this further by implementing a more advanced power
>> management features for the kernel drivers.
>> The DVFS support is opt-in for all boards, meaning that older DTBs will
>> continue to work like they did it before this series. It should be possible
>> to easily add the core voltage scaling support for Tegra114+ SoCs based on
>> this grounding work later on, if anyone will want to implement it.
> The same comment as for your interconnect work: for sets touching
> multiple systems please mention the dependencies between patches in the
> cover letter. Not as a reply to such remark like I make here, but as a
> separate entry in the cover letter.

I'll describe all the dependencies in the next revision, thanks.