Subject: [bug#64907] [PATCH 0/2] gnu: Add rvvm support packages.

From: Juliana Sims <[email-masked]>
Date: Sat, 02 Sep 2023 21:42:48 -0400

Hi Vagrant,

 > It could be a lot of work over time to maintain a patched version of
 > u-boot and/or opensbi, especially if those patches are not going to 
be
 > merged upstream at some point...

I make a point of periodically updating and checking for the continued 
functionality of all new packages I submit to Guix. There is a fair bit 
of RISC-V work I would like to do over the next years so I would have 
no problem extending this personal policy to these packages as well.

 > How much faster? Knowing nothing about RVVM, When I asked on
 > irc.libera.chat #riscv that was basically the question I got...

No idea, but having done a fair bit of RISC-V development on emulators, 
I'm willing to take anything I can get XD

 > Worked around how?

So, that turn of phrase was pretty arbitrary, but the sentiment I 
wished to communicate is that I doubt most developers need Linux to be 
tiny. I don't even understand *why* Linux needs to be shrunk for rvvm; 
perhaps to minimize the disk space or memory given to it? If that's the 
case, then the work-around would be to give it more disk and memory 
from the host.

 > Thinking a little more, from what I recall, the whole point of
 > fw_jump.bin is so that you can dynamically specify the payload at
 > runtime ... why do we need a separate fw_payload.bin created at
 > build-time, if you can just pass a (potentially custom) payload at
 > runtime?

As mentioned in the cover letter, you can drop the opensbi patch if you 
like. I didn't think to test opensbi-generic before packaging this 
patched version, and figured "waste not; want not." However, rvvm does 
not work with any version of u-boot currently in Guix.

Hope this helps with any concerns. Let me know if I need to make any 
changes to the patch(es).

Thanks,
Juli