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Date:   Tue, 6 Jun 2023 09:30:59 +0200
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Subject: Re: [PATCH 3/6] media: dt-bindings: mediatek,vcodec: Remove VDEC_SYS
 for mt8183
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        <nfraprado@collabora.com>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Hans Verkuil <hverkuil-cisco@xs4all.nl>
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        Conor Dooley <conor+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Tiffany Lin <tiffany.lin@mediatek.com>,
        Yunfei Dong <yunfei.dong@mediatek.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, linux-media@vger.kernel.org,
        linux-mediatek@lists.infradead.org
References: <20230605162030.274395-1-nfraprado@collabora.com>
 <20230605162030.274395-4-nfraprado@collabora.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <20230605162030.274395-4-nfraprado@collabora.com>
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Il 05/06/23 18:20, Nícolas F. R. A. Prado ha scritto:
> The binding expects the first register space to be VDEC_SYS. But on
> mt8183, which uses the stateless decoders, this space is used only for
> controlling clocks and resets, which are better described as separate
> clock-controller and reset-controller nodes.
> 
> In fact, in mt8173's devicetree there are already such separate
> clock-controller nodes, which cause duplicate addresses between the
> vdecsys node and the vcodec node. But for this SoC, since the stateful
> decoder code makes other uses of the VDEC_SYS register space, it's not
> straightforward to remove it.
> 
> In order to avoid the same address conflict to happen on mt8183,
> since the only current use of the VDEC_SYS register space in
> the driver is to read the status of a clock that indicates the hardware
> is active, remove the VDEC_SYS register space from the binding and
> describe an extra clock that will be used to directly check the hardware
> status.
> 
> Also add reg-names to be able to tell that this new register schema is
> used, so the driver can keep backward compatibility.
> 
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>