[U-Boot] [RFC PATCH v1 0/9] Add support for applications of overlays in SPL

[Michal Simek]

On 22. 03. 19 15:39, Jean-Jacques Hiblot wrote:
> 
> The purpose of this series is to provide the SPL with ability to apply
> overlays for u-boot. this is only a RFC so far, to get a feedback on the
> approach.
> 
> Our use-case is the support of the daughter boards of the AM65x EVM. In
> Linux, each board is supported by a unique overlay. The presence of the
> boards is detected at runtime, and some useful features (like USB) are
> implemented on those daughter boards. Instead of providing multiple dtbs
> and fall in a combinatorial pit, we propose to use DT overlays.

Not sure if you have it on these boards too but I expect you are able to
detect base board with this code board/ti/common/board_detect.c

How do you detect these daughter cards? Is there additional I2C
connection to them and they have on board eeprom with any format for
detection?
Something similar what it is part of FMC standard/VITA 57.1 with using
FRU spec for daughter card description?
Anyway we are working on FRU parser exactly for this purpose.

Do you also need to apply that overlays in SPL?
Isn't it enough to apply them as the part of board_fdt_blob_setup()?

Thanks,
Michal