Re: [PATCH 2/2] arm64: dts: ti: Add basic support for phyBOARD-Lyra-AM625

[Wadim Egorov]

Am 05.05.23 um 11:39 schrieb Tony Lindgren:
> * Nishanth Menon <nm@xxxxxx> [230504 14:33]:
> > Just wondering: if the carrier board can easily work with different
> > SoMs.. in which case, we could do overlay to create the som + carrier
> > overlay to create rdk dtb - this might allow the scheme to scale to
> > additional SoMs and carrier combinations.. and the SoM dtb could be
> > sufficient for something like a bootloader.
> It might be best to limit the overlay usage to devices that might see
> dual use on the carrier board.. Not sure if setting up the entire
> carrier board makes sense as an overlay :) Not sure if folks want to
> debug boot issues on a remote server for example if an overlay is
> needed to boot with Ethernet :)

Our idea is to create overlays for SoM variants, e.g. an overlay for a SoM 
without SPI NOR flash populated.
If we want to reuse a carrier board, we could factor out the carrier board dts 
into a dtsi file and provide the needed combinations in form of different dts files.

In the bootloader world the situation is a bit different.
Here we would like to have a universal phycore_am62x "board" that should be able 
to handle most carrier board designs using that SoM. And since u-boot is moving 
towards having a single source of device trees, this concept will probably no 
longer work anymore. So your idea with a SoM dtb sounds interesting.
I wonder what ideas other SoM vendors have or how it is handled on other 
architectures.

Regards,
Wadim

> Regards,
>
> Tony