Re: [PATCH v2 1/6] dt-bindings: arm: mediatek: mmsys: change compatible for MT8195

From: Krzysztof Kozlowski
Date: Sun Sep 18 2022 - 05:32:15 EST


On 16/09/2022 04:34, Jason-JH Lin wrote:
> Hi Matthias,
>
> Thanks for the review.
>
> On Fri, 2022-09-16 at 00:05 +0200, Matthias Brugger wrote:
>>
>> On 15/09/2022 18:18, Jason-JH.Lin wrote:
>>> For previous MediaTek SoCs, such as MT8173, there are 2 display HW
>>> pipelines binding to 1 mmsys with the same power domain, the same
>>> clock driver and the same mediatek-drm driver.
>>>
>>> For MT8195, VDOSYS0 and VDOSYS1 are 2 display HW pipelines binding
>>> to
>>> 2 different power domains, different clock drivers and different
>>> mediatek-drm drivers.
>>>
>>> Moreover, Hardware pipeline of VDOSYS0 has these components: COLOR,
>>> CCORR, AAL, GAMMA, DITHER. They are related to the PQ (Picture
>>> Quality)
>>> and they makes VDOSYS0 supports PQ function while they are not
>>> including in VDOSYS1.
>>>
>>> Hardware pipeline of VDOSYS1 has the component ETHDR (HDR related
>>> component). It makes VDOSYS1 supports the HDR function while it's
>>> not
>>> including in VDOSYS0.
>>>
>>> To summarize0:
>>> Only VDOSYS0 can support PQ adjustment.
>>> Only VDOSYS1 can support HDR adjustment.
>>>
>>> Therefore, we need to separate these two different mmsys hardwares
>>> to
>>> 2 different compatibles for MT8195.
>>>
>>> Fixes: 81c5a41d10b9 ("dt-bindings: arm: mediatek: mmsys: add mt8195
>>> SoC binding")
>>> Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
>>> Signed-off-by: Bo-Chen Chen <rex-bc.chen@xxxxxxxxxxxx>
>>> ---
>>> .../devicetree/bindings/arm/mediatek/mediatek,mmsys.yaml |
>>> 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git
>>> a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yam
>>> l
>>> b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yam
>>> l
>>> index 6ad023eec193..0e267428eaa6 100644
>>> ---
>>> a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yam
>>> l
>>> +++
>>> b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yam
>>> l
>>> @@ -31,7 +31,7 @@ properties:
>>> - mediatek,mt8183-mmsys
>>> - mediatek,mt8186-mmsys
>>> - mediatek,mt8192-mmsys
>>> - - mediatek,mt8195-mmsys
>>> + - mediatek,mt8195-vdosys0
>>
>> Nack, we miss the fallback compatible, as I already said twice.
>>
>> Regards,
>> Matthias
>
> I'm sorry this happened again.
> I'll keep the compatible "mediatek,mt8195-mmsys" at next version.
>
> The patch "dt-bindings: arm: mediatek: mmsys: remove the unused
> compatible for mt8195" should be sent after accepting the vdosys1
> series, right?

I don't think there will be no such patch...

You need to add a bindings change which will accept device nodes like:
foo {
compatible = "mediatek,mt8195-vdosys0", "mediatek,mt8195-mmsys";

}

Example-schema shows how to do it.

Best regards,
Krzysztof