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Date: Mon, 20 May 2024 17:34:58 +0200
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Subject: Re: [PATCH v4 3/3] drm/mediatek: Implement OF graphs support for
 display paths
To: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>,
 chunkuang.hu@kernel.org
Cc: robh@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org,
 p.zabel@pengutronix.de, airlied@gmail.com, daniel@ffwll.ch,
 maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de,
 matthias.bgg@gmail.com, shawn.sung@mediatek.com, yu-chang.lee@mediatek.com,
 ck.hu@mediatek.com, jitao.shi@mediatek.com, devicetree@vger.kernel.org,
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References: <20240516081104.83458-1-angelogioacchino.delregno@collabora.com>
 <20240516081104.83458-4-angelogioacchino.delregno@collabora.com>
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From: Alexandre Mergnat <amergnat@baylibre.com>
In-Reply-To: <20240516081104.83458-4-angelogioacchino.delregno@collabora.com>
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Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Tested-by: Alexandre Mergnat <amergnat@baylibre.com>

On 16/05/2024 10:11, AngeloGioacchino Del Regno wrote:
> It is impossible to add each and every possible DDP path combination
> for each and every possible combination of SoC and board: right now,
> this driver hardcodes configuration for 10 SoCs and this is going to
> grow larger and larger, and with new hacks like the introduction of
> mtk_drm_route which is anyway not enough for all final routes as the
> DSI cannot be connected to MERGE if it's not a dual-DSI, or enabling
> DSC preventively doesn't work if the display doesn't support it, or
> others.
> 
> Since practically all display IPs in MediaTek SoCs support being
> interconnected with different instances of other, or the same, IPs
> or with different IPs and in different combinations, the final DDP
> pipeline is effectively a board specific configuration.
> 
> Implement OF graphs support to the mediatek-drm drivers, allowing to
> stop hardcoding the paths, and preventing this driver to get a huge
> amount of arrays for each board and SoC combination, also paving the
> way to share the same mtk_mmsys_driver_data between multiple SoCs,
> making it more straightforward to add support for new chips.

-- 
Regards,
Alexandre