[XL] Change in coreboot[main]: payloads: Add uefistub payload

[Simon Glass (Code Review)]

Attention is currently required from: Benjamin Doron, Martin L Roth, Maximilian Brune, Patrick Rudolph.

Simon Glass has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78913?usp=email )

Change subject: payloads: Add uefistub payload
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Patch Set 4:

(1 comment)

Patchset:

PS4: 
I struggle to understand the goal here. We already have U-Boot as a payload which can boot into Linuxboot and provide an EFI interface.

Why do we need to pull pieces out of U-Boot to achieve this? It doesn't seem a very friendly approach to me...particularly as the files do not seem to reference U-Bot as the source. But even if they do, this seems like a fork to me.

A huge amount of work went into making U-Boot support this feature. Much ongoing work is happening to improve it - the code base is under active development.

I believe it would make more sense for coreboot to embrace U-Boot as a first-class coreboot payload, rather than always trying to use something else.

I have been trying hard to get U-Boot to work better as a coreboot payload. U-Boot's CI now boots coreboot to check it works on every PR. I would really like to see some reciprocal efforts, rather than this sort of thing.

Please?