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    SubjectRe: [PATCH v2 0/9] Exynos Adaptive Supply Voltage support
    On 19-08-19, 15:39, Sylwester Nawrocki wrote:
    > Unfortunately not, the patch set as I see it is another way of updating
    > an OPP after it was parsed from DT. OPP remove/add could work equally
    > well in our use case.

    Adding OPPs dynamically has limitations, you can't set many values which are
    otherwise possible with DT. And removing/adding is not the right thing to do
    technically.

    > The problem is that we have the information on how to translate the
    > common OPP voltage to a voltage specific to given silicon encoded jointly
    > in the ASV tables and the CHIPID registers (efuse/OTP memory).
    > Additionally, algorithm of selecting ASV data (OPP voltage) based on
    > the "key" data from registers is not generic, it is usually different
    > per each SoC type.
    >
    > I tried to identify some patterns in those tables in order to simplify
    > possible DT binding, but that was not really successful. I ended up just
    > keeping whole tables.

    Sorry but I am unable to understand the difficulty you are facing now. So what I
    suggest is something like this.

    - Use DT to get a frequency and voltage for each frequency.
    - At runtime, based on SoC, registers, efuses, etc, update the voltage of the
    OPPs.
    - This algo can be different for each SoC, no one is stopping you from doing
    that.

    Am I missing something ?

    --
    viresh

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