Re: [PATCH v3 00/14] arm64: dts: imx8mm-kontron: DT updates

From: Frieder Schrempf <frieder.schrempf@kontron.de>
To: Shawn Guo <shawnguo@kernel.org>,
	Frieder Schrempf <frieder@fris.de>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc: Conor Dooley <conor+dt@kernel.org>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Alexander Stein <alexander.stein@ew.tq-group.com>,
	Fabio Estevam <festevam@gmail.com>,
	Gregor Herburger <gregor.herburger@ew.tq-group.com>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	Marcel Ziswiler <marcel.ziswiler@toradex.com>,
	Marek Vasut <marex@denx.de>, NXP Linux Team <linux-imx@nxp.com>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Philippe Schenker <philippe.schenker@toradex.com>,
	Tim Harvey <tharvey@gateworks.com>
Subject: Re: [PATCH v3 00/14] arm64: dts: imx8mm-kontron: DT updates
Date: Mon, 8 Jan 2024 09:54:14 +0100	[thread overview]
Message-ID: <a618fb58-fdcc-41b3-a3fa-72025477a481@kontron.de> (raw)
In-Reply-To: <5bdfefe3-238a-48d3-b8a4-cee4fb6b0951@kontron.de>

On 19.12.23 16:14, Frieder Schrempf wrote:
> On 13.12.23 10:31, Shawn Guo wrote:
>> On Wed, Dec 06, 2023 at 03:41:03PM +0100, Frieder Schrempf wrote:
>>> From: Frieder Schrempf <frieder.schrempf@kontron.de>
>> ...
>>>  arch/arm64/boot/dts/freescale/Makefile        |   4 +
>>>  .../dts/freescale/imx8mm-kontron-bl-osm-s.dts | 295 +++------
>>>  .../boot/dts/freescale/imx8mm-kontron-bl.dts  | 198 +++++-
>>>  .../boot/dts/freescale/imx8mm-kontron-dl.dtso | 201 +++++++
>>>  .../dts/freescale/imx8mm-kontron-osm-s.dtsi   | 567 +++++++++++++++++-
>>>  .../boot/dts/freescale/imx8mm-kontron-sl.dtsi |   4 +-
>>>  6 files changed, 1035 insertions(+), 234 deletions(-)
>>>  create mode 100644 arch/arm64/boot/dts/freescale/imx8mm-kontron-dl.dtso
>>
>> A couple of things:
>>
>> - I have to use 'git am -3' apply some of the patches.  Could you rebase
>>   the series on imx/dt64 branch?
> 
> Ok, sure!
> 
>>
>> - There are a few DTC warnings that need to be addressed.
>>
>> ../arch/arm64/boot/dts/freescale/imx8mm-kontron-bl.dts:235.34-238.7: Warning (graph_endpoint): /soc@0/bus@30800000/i2c@30a40000/bridge@2c/ports/port@0/endpoint: graph connection to node '/soc@0/bus@32c00000/dsi@32e10000/ports/port@1/endpoint' is not bidirectional
> 
> I'm not aware of a proper solution for this warning. The thing is that
> there is a DSI switch on the board that is able to route the DSI output
> of the SoC to one of two bridges (HDMI or LVDS).
> 
> On the driver side there is no representation of the switch. Therefore
> the result is a three-way connection for the graph ports which is
> reported by the binding check, but works fine as we only enable one of
> the target port nodes at a time and use GPIO hogs to select the switch path.
> 
> Rob, Krzystztof: Would it be acceptable to ignore this until there is a
> way to represent this in the DT? Are there alternative solutions? Is
> there anything to model a graph link switch?
> 
>> arch/arm64/boot/dts/freescale/imx8mm-kontron-dl.dtbo: Warning (graph_port): /fragment@3: graph port node name should be 'port'
>> ../arch/arm64/boot/dts/freescale/imx8mm-kontron-dl.dtso:61.17-63.3: Warning (graph_endpoint): /fragment@3/__overlay__: graph endpoint node name should be 'endpoint'
> 
> For these warnings it seems like I could work around them by creating
> two separate port nodes in the board DT and then only enable the proper
> one in the overlay.

Until I find out how to deal with the DTC warnings above, I sent a v4
without the display support patches to unblock the merging of the other
patches.