Message-ID: <6a2b0750-b71b-409e-7e9d-df0f3fa71a2e@samsung.com>
Date:   Sat, 28 Jan 2023 23:55:36 +0100
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Subject: Re: [PATCH 2/9] ARM: dts: exynos: move exynos-bus nodes out of soc
 in Exynos5420
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To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Kukjin Kim <kgene@kernel.org>, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     replicant@osuosl.org, phone-devel@vger.kernel.org,
        ~postmarketos/upstreaming@lists.sr.ht,
        =?UTF-8?Q?Martin_J=c3=bccker?= <martin.juecker@gmail.com>,
        Henrik Grimler <henrik@grimler.se>,
        Chanwoo Choi <cw00.choi@samsung.com>
From:   Marek Szyprowski <m.szyprowski@samsung.com>
In-Reply-To: <4dea3da5-54b6-bc50-a802-cb73ddccf5d8@linaro.org>
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References: <20230125094513.155063-1-krzysztof.kozlowski@linaro.org>
        <CGME20230125094529eucas1p29b5f25af2c658abef13a93c49eca975f@eucas1p2.samsung.com>
        <20230125094513.155063-2-krzysztof.kozlowski@linaro.org>
        <cd42b8c9-a79a-068c-a967-810c05e818bd@samsung.com>
        <d8f5fa57-da3a-09f9-e297-197068264d26@linaro.org>
        <4dea3da5-54b6-bc50-a802-cb73ddccf5d8@linaro.org>
Precedence: bulk

On 28.01.2023 11:43, Krzysztof Kozlowski wrote:
> On 26/01/2023 11:59, Krzysztof Kozlowski wrote:
>> On 26/01/2023 10:47, Marek Szyprowski wrote:
>>> Hi Krzysztof,
>>>
>>> On 25.01.2023 10:45, Krzysztof Kozlowski wrote:
>>>> The soc node is supposed to have only device nodes with MMIO addresses,
>>>> as reported by dtc W=1:
>>>>
>>>>     arch/arm/boot/dts/exynos5420.dtsi:1070.24-1075.5:
>>>>       Warning (simple_bus_reg): /soc/bus-wcore: missing or empty reg/ranges property
>>>>
>>>> and dtbs_check:
>>>>
>>>>     exynos5420-arndale-octa.dtb: soc: bus-wcore:
>>>>       {'compatible': ['samsung,exynos-bus'], 'clocks': [[2, 769]], 'clock-names': ['bus'], 'status': ['disabled']} should not be valid under {'type': 'object'}
>>>>
>>>> Move the bus nodes and their OPP tables out of SoC to fix this.
>>>> Re-order them alphabetically while moving and put some of the OPP tables
>>>> in device nodes (if they are not shared).
>>>>
>>>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>> Frankly speaking I'm not very keen on moving those bus nodes out of
>>> /soc. Technically speaking this is definitely a part of soc and doesn't
>>> make much sense outside of it. IMHO they describe SoC hardware details
>>> and they might be moved somehow under clock controller device(s),
>>> although this would require some changes in the bindings and drivers.
>> That's the only way to fix it without change of drivers any ABI
>> compatibility issue. The same we do for Qualcomm interconnects, e.g.
>> arch/arm64/boot/dts/qcom/sm8450.dtsi where some interconnects have some
>> do not have MMIO space.
>>
>> I want to achieve finally clean dtbs_check run for all Exynos sources.
>> The in-tree bindings already pass, so now I am fixing the ones coming
>> from dtschema (simple-bus.yaml in particular).
>>
>> If you have any other idea how to seamlessly clean it up, I am happy to
>> hear. But I guess the main problem is that no one is being paid for
>> doing anything for Samsung Exynos, so for free not many put much effort
>> into working on it.
> Marek, I value your feedback a lot and I appreciate your help here. Just
> to be clear that I am not ignoring it, little disclaimer:
>
> Unless there is a clear NAK from you or someone else, with an idea to
> fix or with a commitment to change driver/bindings, I am planning to
> grab these changes.
>
> I really want to get the dtbs_check done. With these and my other fixes,
> the arm64 exynos DTS pass fully all dtschema and in-kernel dtbs_check.

Go ahead. I won't block it.

Best regards

-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland