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Date:   Wed, 03 May 2023 16:22:32 +0200
Message-Id: <CSCPKPC8OB80.1TTBCM3YDVJQ5@void.crly.cz>
Subject: Re: [PATCH v2 0/7] drm: sun4i: set proper TCON0 DCLK rate in DSI
 mode
From:   "Roman Beranek" <me@crly.cz>
To:     "Frank Oltmanns" <frank@oltmanns.dev>,
        "Maxime Ripard" <mripard@kernel.org>,
        "Jernej Skrabec" <jernej.skrabec@gmail.com>
Cc:     "Chen-Yu Tsai" <wens@csie.org>, "David Airlie" <airlied@gmail.com>,
        "Daniel Vetter" <daniel@ffwll.ch>,
        "Samuel Holland" <samuel@sholland.org>,
        "Ondrej Jirman" <megi@xff.cz>, <dri-devel@lists.freedesktop.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-sunxi@lists.linux.dev>, <linux-kernel@vger.kernel.org>
References: <20230418074008.69752-1-me@crly.cz>
 <87cz3uzpx1.fsf@oltmanns.dev> <87mt2o9njh.fsf@oltmanns.dev>
In-Reply-To: <87mt2o9njh.fsf@oltmanns.dev>
Precedence: bulk

Hello everyone,

I apologize for my absence from the discussion during past week, I got
hit with tonsillitis.

On Mon May 1, 2023 at 3:40 PM CEST, Frank Oltmanns wrote:
> Looking at ccu_nkm_determine_rate(), we've found our culprit because it
> does not try parent clock rates other than the current one. The same
> applies to all other ccu_nkm_* functions.

Yes, that's why I dropped CLK_SET_RATE_PARENT from pll-mipi in v3.

>  b. Add functionality to ccu_nkm_* to also update the parent clock rate.
>
> I'm actually interested in tackling b, but I can't make any promises as
> to if and when I'll be able to solve it. I'm not certain about any side
> effects this might have.

It sounds like an interesting exercise. But what if HDMI is then added
to the mix?

Best regards
Roman