[RFC] arm64: dts: freescale: Supporting Variscite SoM and carrier revisions

[Frank Li]

On Mon, Oct 26, 2026 at 09:29:39AM +0100, Stefano Radaelli wrote:
> Hi Frank,
>
> On Fri, Oct 23, 2026 at 10:15:36AM -0500, Frank Li wrote:
> > >
> > >   imx8mm-var-dart-2.2-sonata-1.4.dtb
> > >     DART-MX8M Mini v2.2 on Sonata v1.4
> > >
> > > These are proposed names, assuming that the same DT correctly describes
> > > all the hardware combinations covered by each entry.
> >
> > If new boards 2.3 appear, do you plan change to
> > imx8mm-var-dart-2.2-sonata-1.4-2.3.dtb?
> >
> > Rename affect addtional problem or efforts when back port.
>
> No, our intention is to keep the filename unchanged. For example,
> imx8mm-var-dart-2.0-sonata-1.0.dtb would retain that name even if it
> also supports later revisions, provided that the same description
> remains correct for all previously supported hardware.
>
> Regarding the filename itself, would it be acceptable to include both
> the SoM and carrier hardware revisions, as in the example above?

Is it for created dtb file? We generally doesn't finial results.

> Or is there a preferred upstream naming convention for distinguishing
> these combinations? I have not found a clear example to follow where
> both revisions are included in the filename.
>
> We would introduce a separate DTS/DTB only when the hardware requires
> a different description, sharing the common parts through .dtsi files.
> Our preference is to distribute complete DTBs that the bootloader
> can load directly.

It should be fine only if dts can be shared. It is okay to generate differe
combination dtb file by using makefile.

>
> > How about use boards compatible string? You add new compatible for new
> > boards, so user know this dts cover which boards.
>
> Could you give an example of how you would handle the root compatible
> property when the same DTB is used unchanged on multiple revisions?
>
> For instance, if SoM v2.0 and v2.1 on the same carrier can share exactly
> the same DT, would you retain the existing board compatible, or
> introduce revision-specific strings? How would those be represented
> in the shared DTS?

Yes, need revision-specific compatible string.

compatible = "SoM2.1-carrier-0.1", "SoMv2.0-carrier-0.2", ....

Frank

>
> Thanks,
> Stefano