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Date:   Tue, 27 Jun 2023 11:07:22 +0200
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Subject: Re: [PATCH 03/15] dt-bindings: clock: qcom,dispcc-sm6125: Require GCC
 PLL0 DIV clock
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To:     Marijn Suijten <marijn.suijten@somainline.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Cc:     Konrad Dybcio <konrad.dybcio@linaro.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Krishna Manikandan <quic_mkrishn@quicinc.com>,
        ~postmarketos/upstreaming@lists.sr.ht,
        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Martin Botka <martin.botka@somainline.org>,
        Jami Kettunen <jami.kettunen@somainline.org>,
        linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org,
        dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org,
        Lux Aliaga <they@mint.lgbt>
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From:   Krzysztof Kozlowski <krzk@kernel.org>
In-Reply-To: <makhh4ebdmoa5f6r4mbx4g2v2cpcsi74wqf3622dxuli4w7tb6@els2rvqcnvgz>
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On 27/06/2023 11:02, Marijn Suijten wrote:
>>>>> So deleting a new item at the end does not matter.  But what if I respin
>>>>> this patch to add the new clock _at the end_, which will then be at the
>>>>> same index as the previous GCC_DISP_AHB_CLK?
>>>>
>>>> I think you know the answer, right? What do you want to prove? That two
>>>> independent changes can have together negative effect? We know this.
>>>
>>> The question is whether this is allowed?
>>
>> That would be an ABI break and I already explained if it is or is not
>> allowed.
> 
> How should we solve it then, if we cannot remove GCC_DISP_AHB_CLK in one
> patch and add GCC_DISP_GPLL0_DIV_CLK_SRC **at the end** in the next
> patch?  Keep an empty spot at the original index of GCC_DISP_AHB_CLK?

I don't know if you are trolling me or really asking question, so just
in case it is the latter:

"No one is locked into the ABI. SoC maintainer decides on this. "

Also:
https://lore.kernel.org/linux-arm-msm/20230608152759.GA2721945-robh@kernel.org/

https://lore.kernel.org/linux-arm-msm/CAL_JsqKOq+PdjUPVYqdC7QcjGxp-KbAG_O9e+zrfY7k-wRr1QQ@mail.gmail.com/

https://lore.kernel.org/linux-arm-msm/20220602143245.GA2256965-robh@kernel.org/

https://lore.kernel.org/linux-arm-msm/20220601202452.GA365963-robh@kernel.org/

Any many more.

Best regards,
Krzysztof