Unable to implement board fdt-fixup for imx8m CPU

[Rasmus Villemoes]

On 25/04/2023 04.17, Hugo Villeneuve wrote:

> I need to detect at runtime the SOM configuration from an EEPROM, and based on that information adjust the ethernet PHY property inside the device tree.
> 
> I have already done that with success, it works great and as a temporary workaround I simply call my own function imx8m_board_fix_fdt() at the end of the function board_fix_fdt() of arch/arm/mach-imx/imx8m/soc.c.
> 
> But I don't think that a "board" level function should have been put in a SOC/arch source file in arch/arm/mach-imx/imx8m/soc.c in the first place. If it were not for that, there wouldn't be any need to define something new (event or other).
> 
> Maybe we should try to remove that board level function from arch/arm/mach-imx/imx8m/soc.c and use some other already existing mechanism for SOC-level device tree fixups?

AFAICT, you/we can just nuke that function completely.

(1) As you say, it's not appropriate for arch/SOC to provide that in the
first place.
(2) It's completely dead and useless code:
(2a) No in-tree imx8m-based board seems to set CONFIG_OF_BOARD_FIXUP
(2b) The nodes which that function wants to disable don't even exist in
the U-Boot copy of imx8mp.dtsi.

Commit 35bb60787b88 should never have been applied in mainline U-Boot,
it's some random import of code from downstream NXP U-Boot, with a
commit message that makes no sense in upstream context.

Rasmus