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Subject: Re: [PATCH 2/3] [media] tc358743: Increase FIFO level to 300.
From: Philipp Zabel <p.zabel@pengutronix.de>
To: Dave Stevenson <dave.stevenson@raspberrypi.org>,
        Mats Randgaard <matrandg@cisco.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Hans Verkuil <hans.verkuil@cisco.com>,
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Date: Tue, 19 Sep 2017 17:24:45 +0200
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Hi Dave,

On Tue, 2017-09-19 at 14:08 +0100, Dave Stevenson wrote:
> The existing fixed value of 16 worked for UYVY 720P60 over
> 2 lanes at 594MHz, or UYVY 1080P60 over 4 lanes. (RGB888
> 1080P60 needs 6 lanes at 594MHz).
> It doesn't allow for lower resolutions to work as the FIFO
> underflows.
> 
> Using a value of 300 works for all resolutions down to VGA60,
> and the increase in frame delay is <4usecs for 1080P60 UYVY
> (2.55usecs for RGB888).
> 
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>

Can we increase this to 320? This would also allow
720p60 at 594 Mbps / 4 lanes, according to the xls.

regards
Philipp