[U-Boot] SPL Platdata howto?

[Simon Goldschmidt]

Hi,

while searching for bytes to save in SPL in order to add FIT signature 
handling, I am currently trying to get socfpga-gen5 to use OF_PLATDATA.

To begin, I stripped down socfpga_socrates_defconfig to absolutely 
nothing but serial drivers in SPL (with some modifications to the 
Kconfig) and enabled DEBUG_UART to see what's going on.

Now while this config runs OK with a dtb (it just won't boot as drivers 
are missing -> "failed to boot from all boot devices"), it does not find 
the serial driver after enabling OF_PLATDATA.

So since serial_rockchip.c already uses OF_PLATDATA and is based on 
ns16550 that my socfpga-gen5 platform is using: what do I have to do 
besides enabling OF_PLATDATA to get this working?

I just seems like uclass_first_device does not find any UCLASS_SERIAL 
deivce when OF_PLATDATA is enabled.

(And when answering this, keep in mind I need to get MMC and QSPI 
drivers working with OF_PLATDATA - I already fixed compiler errors in 
those, nothing more.)

Thanks,
Simon