Re: [PATCH v4 0/4] drm: sun4i: set proper TCON0 DCLK rate in DSI mode

From: Frank Oltmanns <frank@oltmanns.dev>
To: Roman Beranek <me@crly.cz>
Cc: Maxime Ripard <mripard@kernel.org>,
	David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
	Chen-Yu Tsai <wens@csie.org>,
	Jernej Skrabec <jernej.skrabec@gmail.com>,
	Samuel  Holland <samuel@sholland.org>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>, Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Icenowy Zheng <icenowy@aosc.io>, Ondrej Jirman <megi@xff.cz>,
	devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org,
	linux-arm-kernel@lists.infradead.org,
	linux-sunxi@lists.linux.dev, linux-clk@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 0/4] drm: sun4i: set proper TCON0 DCLK rate in DSI mode
Date: Wed, 10 May 2023 06:30:04 +0200	[thread overview]
Message-ID: <874jokg5sf.fsf@oltmanns.dev> (raw)
In-Reply-To: <CSHP4M31IC80.2WGQC75I3PX71@void.crly.cz>

Hello Roman,

On 2023-05-09 at 13:04:50 +0200, "Roman Beranek" <me@crly.cz> wrote:
> On Mon May 8, 2023 at 10:47 AM CEST, Frank Oltmanns wrote:
>> I played back a 60 fps video (10 seconds) and recorded the panel's
>> output with a 240 fps camera. I noticed only 2 dropped frames, that I
>> account to the imperfect data rate of 107.8MHz instead of 108 MHz due
>> to pll-video0's rate being 294MHz instead of the 297 MHz for reasons
>> I described in the thread on your v2 of this patch [4]).
>
> Yes. That's what should happen, right? Or do you report this as a
> defect?

Sorry, I didn't communicate more clearly. Without your patch, I'm losing
a number of frames in the realm of three digits. With your patch I only
lost 2 frames which is expetcted. Your patches are a big improvement.

This is the opposite of a defect report. :-)

Thanks,
  Frank

>
> Roman