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Date: Sat, 07 Dec 2024 07:30:27 +0100
From: Nikolaus Voss <nv@vosn.de>
To: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Alexander Stein <alexander.stein@ew.tq-group.com>, Liu Ying
 <victor.liu@nxp.com>, Luca Ceresoli <luca.ceresoli@bootlin.com>, Fabio
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 <andrzej.hajda@intel.com>, Neil Armstrong <neil.armstrong@linaro.org>,
 Robert Foss <rfoss@kernel.org>, Laurent Pinchart
 <Laurent.pinchart@ideasonboard.com>, Jonas Karlman <jonas@kwiboo.se>, Jernej
 Skrabec <jernej.skrabec@gmail.com>, David Airlie <airlied@gmail.com>, Daniel
 Vetter <daniel@ffwll.ch>, nikolaus.voss@haag-streit.com,
 dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] drm: bridge: fsl-ldb: fixup mode on freq mismatch
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Hi Miquèl,

On 06.12.2024 15:08, Miquel Raynal wrote:
> On 03/12/2024 at 20:09:52 +01, Nikolaus Voss <nv@vosn.de> wrote:
> 
>> LDB clock has to be a fixed multiple of the pixel clock.
> 
> Not only, IIUC it also needs to be synchronized, ie. share the same
> source.
> 
>> As LDB and pixel clock are derived from different clock sources
>> (at least on imx8mp),
> 
> Wait, what? I am sorry but that is not at all recommended, both should
> come from video_pll1 which the de-facto versatile PLL to use, no? Am I
> missing something here?

No, I was wrong :-). I've corrected the log text in the v3.

-- 
Nikolaus Voss