Booting compressed payloads from cbfsdisk?

[Rafael Send]

Hi,
I'm using coreboot with a grub 2 payload. Works great, generally.

However to save space in ROM I want to compress the other payloads which
are executed by grub out of cbfs, according to the coreboot wiki this is
possible.

However, I've tried both lzma and lz4 compressed payloads and each time
grub tells me: "unknown payload type".

It will load non-compressed ones just fine.

If booting such compressed payloads is indeed supported, what is the
correct way of doing so?

Thanks,
Rafael