[PATCH] board: rzg2l: Do not expect a DTB blob from the TF-A.

[Marek Vasut]

On 9/18/25 2:48 PM, Mathieu Othacehe wrote:
> On the RZG2L platform, the advised
> TF-A (https://github.com/renesas-rz/rzg_trusted-firmware-a/tree/v2.5/rzg2l)
> does not pass any DTB blob to U-Boot.
> 
> On the other hand, the RZG2L part of U-Boot expects a DTB to be passed.  It
> means that if one flashes the latest TF-A as well as the mainline U-Boot,
> it will crash trying to dereference the NULL DTB pointer before outputing
> anything, which is painful to debug.

This part is unexpected ...

[...]

> -int board_fit_config_name_match(const char *name)
> -{
> -	void *atf_fdt_blob = (void *)(rcar_atf_boot_args[1]);
> -
> -	if (fdt_magic(atf_fdt_blob) != FDT_MAGIC)
... because every function which handles such passed DT is testing its 
DT magic validity first. Is the magic actually valid in your fail case?

Also, enable CONFIG_DEBUG_UART in your U-Boot config, then you will get 
very early UART output capabilities, it works even before DT is used.