Re: [PATCH 1/3] dt-bindings: cpufreq: qcom-cpufreq-nvmem: make cpr bindings optional

From: Krzysztof Kozlowski
Date: Sun Jan 22 2023 - 09:13:30 EST


On 22/01/2023 15:05, Christian Marangi wrote:
> On Sun, Jan 22, 2023 at 02:57:07PM +0100, Krzysztof Kozlowski wrote:
>> On 21/01/2023 01:01, Christian Marangi wrote:
>>> The qcom-cpufreq-nvmem driver also supports legacy devices pre-cpr that
>>> doesn't have power-domains. When the schema was introduced, it was
>>> wrongly set to always require these binding but this is not the case for
>>> legacy device that base everything on nvmem cells and multiple microvolt
>>
>> What is a "legacy device"? Why do you adjust bindings to legacy device?
>> Can't you just fix the DTS on these devices?
>>
>
> With legacy I mean device where cpr (core power reduction) wasn't a
> thing and qcom used a different way to select the microvolt for the opp.
>
> There is nothing in the related DTS to fix since they are not broken.
> The driver doesn't enforce cpr presence and supports both new and old
> implementation...
>
> Setting the cpr as a required binding was wrong from the start. It was
> probably done when qcs404 was introduced and they had this bright idea
> of creating the schema and ignoring the other kind of configuration the
> driver supports.
>
> Since now we want to send opp for ipq8064 that use the old
> implementation this fixup is required.
>
> Probably I should drop the legacy term and just say that the driver
> supports 2 different configuration and the following schema permits only
> one?

Yes, it would be clearer.

Best regards,
Krzysztof