Date:   Tue, 7 Feb 2023 19:44:53 +0100
From:   Francesco Dolcini <francesco@dolcini.it>
To:     Nishanth Menon <nm@ti.com>, Vignesh Raghavendra <vigneshr@ti.com>,
        Dave Gerlach <d-gerlach@ti.com>
Cc:     Tero Kristo <kristo@kernel.org>, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, francesco.dolcini@toradex.com
Subject: K3 AM62x SoC dts/dtsi include hierarchy and naming scheme
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Hello Vignesh and all,
I am writing you to get some clarification on the way the dts/dtsi
naming and include hierarchy is designed for the TI K3 AM62x SOC family.

I read commit f1d17330a5be ("arm64: dts: ti: Introduce base support for AM62x SoC").

I plan to send in the next few weeks some device tree files for
inclusion in the kernel for SOM (or computer on module) based on the
AM62x SOC.

I do envision to have the same dts file for different machine that are
going to use different variant of the AM62x SOC, e.g. AM623 vs AM625 or
just a different number of CPU cores, handling the differences at
runtime (patching the .dtb in U-Boot?) to limit the maintenance effort and
limit the amount of very similar dts files.

Said that we would prefer to stay close with what is considered/agreed
to be the best approach.

Would something like that work or you would have a completely different
expectation?

What would be the expected naming scheme? k3-am62-${board_name}.dts ?
Something else?

k3-am625.dtsi defines the CPU nodes, why are these in a AM625 specific
file? To me this looks like something that would be just the same with
AM623, and at the same time AM6251 has only one core (see [0] Table 5-1).
Am I missing something?

Thanks for your help,
Francesco

[0] https://www.ti.com/lit/ds/symlink/am625.pdf