Re: [PATCH 15/16] misc: lan966x_pci: Add dtso nodes in order to support SFPs

Thomas Petazzoni
2025-04-09T07:44:30Z

On Tue Apr 8, 2025 at 5:38 PM CEST, Andrew Lunn wrote:

> "HW blocks inside an SoC." That would be the SoC .dtsi file. Anything
> outside of the SoC is in the .dts file. OEM vendors take the SoC,
> build a board around it, and name there .dts file after the board,
> describing how the board components are connected to the SoC.
>
> So..
>
> So by PCI endpoint, you mean the PCIe chip? So it sounds like there
> should be a .dtsi file describing the chip.
>
> Everything outside of the chip, like the SFP cages, are up to the
> vendor building the board. I would say that should be described in a
> .dtso file, which describes how the board components are connected to
> the PCIe chip? And that .dtso file should be named after the board,
> since there are going to many of them, from different OEM vendors.

Indeed, that makes sense. So if I get correctly your suggestion,
instead of having a .dtso that describes everything, it should be
split between:

- A .dtsi that describes what's inside the LAN996x when used in PCI
endpoint mode

- A .dtso that includes the above .dtsi, and that describes what on
the PCI board around the LAN966x.

Correct?

Thomas
--
Thomas Petazzoni, co-owner and CEO, Bootlin
Embedded Linux and Kernel engineering and training