Re: [PATCH v5 1/4] dt-bindindgs: i2c: qcom,i2c-geni: Document shared flag
From: Krzysztof Kozlowski
Date: Tue Dec 10 2024 - 10:56:51 EST
>> There would be spare register but i think it should be in sync with hardware team. let me check with them and update back if any bit can be repurposed for this feature. I agree, if any register is available, it can programmed prior to kernel.
>>> It would need to be reserved on all SoCs though (future and
>>> past), to make sure the contract is always held up, but I
>>> think finding a persistent bit that has never been used
>>> shouldn't be impossible.
>>>
>> Yes, let me check it with hardware and firmware team and update back. Does this mean, there can't be a such software sharing mechanism (purely software decision) based on DTSI flag ?
>
> I suppose that depends on our needs. If we can set that bit
> before Linux starts (i.e. in UEFI), we can avoid touching
> the pinctrl state regardless of whether the other entities
> have started up yet to avoid overcomplicating it.
>
> If we need Linux to set that bit, we would still need some
> mechanism like a dt property. But I really think that the
> bootloader should be burdened with this instead, given it
> has a better understanding of the hardware due to it being
> well, the bootloader).
>
> Krzysztof, I'm assuming that sounds sane from your
> perspective too?
Yes, sound okay.
Best regards,
Krzysztof