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Message-ID: <3e197ec0-154f-78b6-3bf1-12cf765a3cc6@collabora.com>
Date:   Thu, 5 Oct 2023 14:41:22 +0200
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Subject: Re: [PATCH] arm64: dts: mediatek: mt8186: fix clock names for power
 domains
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To:     Eugen Hristev <eugen.hristev@collabora.com>, matthias.bgg@gmail.com
Cc:     allen-kh.cheng@mediatek.com, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org
References: <20231005103041.352478-1-eugen.hristev@collabora.com>
From:   AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
In-Reply-To: <20231005103041.352478-1-eugen.hristev@collabora.com>
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Il 05/10/23 12:30, Eugen Hristev ha scritto:
> Clocks for each power domain are split into big categories: pd clocks
> and subsys clocks.
> According to the binding, all clocks which have a dash '-' in their name
> are treated as subsys clocks, and must be placed at the end of the list.
> The other clocks which are pd clocks must come first.
> Fixed the naming and the placing of all clocks in the power domains.
> For the avoidance of doubt, prefixed all subsys clocks with the 'subsys'
> prefix. The binding does not enforce strict clock names, the driver
> uses them in bulk, only making a difference for pd clocks vs subsys clocks.
> 
> The above problem appears to be trivial, however, it leads to incorrect
> power up and power down sequence of the power domains, because some
> clocks will be mistakenly taken for subsys clocks and viceversa.
> One consequence is the fact that if the DIS power domain goes power down
> and power back up during the boot process, when it comes back up, there
> are still transactions left on the bus which makes the display inoperable.
> 
> Some of the clocks for the DIS power domain were wrongly using '_' instead
> of '-', which again made these clocks being treated as pd clocks instead of
> subsys clocks.
> 
> Fixes: d9e43c1e7a38 ("arm64: dts: mt8186: Add power domains controller")
> Signed-off-by: Eugen Hristev <eugen.hristev@collabora.com>

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