Unable to implement board fdt-fixup for imx8m CPU

[Hugo Villeneuve]

On Mon, 24 Apr 2023 15:01:35 -0600
Simon Glass <sjg at chromium.org> wrote:

> Hi Hugo,
> 
> On Mon, 24 Apr 2023 at 14:53, Hugo Villeneuve <hugo at hugovil.com> wrote:
> >
> > Hi,
> > according to this document:
> >
> >     doc/develop/driver-model/fdt-fixup.rst
> >
> > it is suggested that boards implement the board_fix_fdt() function to tweak the device tree. I am trying to do just that, but unfortunately I cannot because the following source file already has an implementation of board_fix_fdt():
> >
> >     arch/arm/mach-imx/imx8m/soc.c
> >
> > For all boards using a imx8m CPU, how can we implement board_fix_fdt()?
> 
> If you enable CONFIG_EVENT you can use EVT_FT_FIXUP to add as many
> fixup functions as you need.
> 
> Migration to use that mechanism everywhere hasn't really started, but
> I think it would be useful.

Hi Simon,
to be more precise, I need to modify the FDT used by U-Boot to tweak some ethernet PHY properties before initializing the ethernet controller. I do _not_ need to fix the FDT before booting in the OS.

With that in mind, do you still think using CONFIG_EVENT is the way to go? I am not sure from my reading of the source code because it seems that fixup events are called just before booting into the OS.

Thank you,
Hugo.