Message-ID: <1662a593-8a5d-9214-8a3e-ef2699a35265@ti.com>
Date:   Sun, 5 Feb 2023 20:01:43 +0530
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Subject: Re: [PATCH v7 3/6] drm/tidss: Add support for AM625 DSS
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To:     Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Jyri Sarha <jyri.sarha@iki.fi>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>
CC:     DRI Development List <dri-devel@lists.freedesktop.org>,
        Devicetree List <devicetree@vger.kernel.org>,
        Linux Kernel List <linux-kernel@vger.kernel.org>,
        Nishanth Menon <nm@ti.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Rahul T R <r-ravikumar@ti.com>,
        Devarsh Thakkar <devarsht@ti.com>,
        Jai Luthra <j-luthra@ti.com>,
        Jayesh Choudhary <j-choudhary@ti.com>
References: <20230125113529.13952-1-a-bhatia1@ti.com>
 <20230125113529.13952-4-a-bhatia1@ti.com>
 <ab6f52bb-a3f5-afda-c037-f009153a0bb6@ideasonboard.com>
From:   Aradhya Bhatia <a-bhatia1@ti.com>
In-Reply-To: <ab6f52bb-a3f5-afda-c037-f009153a0bb6@ideasonboard.com>
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On 03-Feb-23 21:03, Tomi Valkeinen wrote:
> On 25/01/2023 13:35, Aradhya Bhatia wrote:
>> Add support for the DSS controller on TI's new AM625 SoC in the tidss
>> driver.
>>
>> The first video port (VP0) in am625-dss can output OLDI signals through
>> 2 OLDI TXes. A 3rd output port has been added with "DISPC_PORT_OLDI" bus
>> type.
> 
> Not a big thing here as you add support for a new SoC, but the ordering
> of the patches is not optimal. Here you add the AM625 DSS support, but
> then you continue actually adding the DSS support (well, mainly OLDI) in
> the following patches.
> 
> I think patch 6 could be before this patch. Parts of patch 4 could also
> be before this patch. The AM65X renames from patch 5 could be before
> this patch.

I can move whole of Patch 6 and even of Patch 4 before this one. I have
mentioned 'AM625-DSS' in a couple comments which I can make generic,
and the rest everything is SoC-agnostic.

I haven't tried this, but my concern is if we break patch 5 into 2
separate patches,

i. AM65X rename plus SoC based switch case, and
ii. Addition of AM625 SoC case

then I might have to overwrite some changes implemented during (i) in
(ii). I don't suppose that would be okay, would it?

Also, is it important to keep the compatible-addition patches of
DT-binding and driver next to each other in the series? Or should
the DT-binding patches should be the first ones? Just curious! =)

> 
> I'm mainly thinking of a case where someone uses AM625 and is bisecting
> a problem. What happens if his board uses OLDI, and he happens to hit
> one of these patches during bisect? If the display just stays black, but
> otherwise everything works fine, then no problem. But if it crashes or
> starts spamming sync losts or such or gives errors, it's not so nice.
> 
You are right! This certainly makes sense.


Regards
Aradhya