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References: <20230517133309.9874-1-ddrokosov@sberdevices.ru> <20230517133309.9874-6-ddrokosov@sberdevices.ru>
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From:   Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date:   Fri, 19 May 2023 23:09:29 +0200
Message-ID: <CAFBinCC3kQ9Nz3R2W-Qj9tbPJfS8JsB_4AkmPgS6xpQ96DBy2w@mail.gmail.com>
Subject: Re: [PATCH v15 5/6] dt-bindings: clock: meson: add A1 Peripherals
 clock controller bindings
To:     Dmitry Rokosov <ddrokosov@sberdevices.ru>,
        krzysztof.kozlowski+dt@linaro.org
Cc:     neil.armstrong@linaro.org, jbrunet@baylibre.com,
        mturquette@baylibre.com, sboyd@kernel.org, robh+dt@kernel.org,
        khilman@baylibre.com, jian.hu@amlogic.com, kernel@sberdevices.ru,
        rockosov@gmail.com, linux-amlogic@lists.infradead.org,
        linux-clk@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
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Hi Krzysztof and Dmitry,

On Wed, May 17, 2023 at 3:33=E2=80=AFPM Dmitry Rokosov <ddrokosov@sberdevic=
es.ru> wrote:
[...]
> +  clocks:
> +    items:
> +      - description: input fixed pll div2
> +      - description: input fixed pll div3
> +      - description: input fixed pll div5
> +      - description: input fixed pll div7
> +      - description: input hifi pll
> +      - description: input oscillator (usually at 24MHz)
> +
> +  clock-names:
> +    items:
> +      - const: fclk_div2
> +      - const: fclk_div3
> +      - const: fclk_div5
> +      - const: fclk_div7
> +      - const: hifi_pll
> +      - const: xtal
This IP block has at least one additional input called "sys_pll_div16".
My understanding is that the "sys_pll_div16" clock is generated by the
CPU clock controller. Support for the CPU clock controller
(dt-bindings and a driver) will be added at a later time by Dmitry.
How can we manage incrementally implementing the clock controllers?
From a hardware perspective the "sys_pll_div16" input is mandatory.
How to manage this in the .dts patches then (for example: does this
mean that Dmitry can only add the clock controller to the .dts when
all clock controller bindings have been implemented - or is there
another way)?


Best regards,
Martin