On 25.06.2017 12:03, Sean Halle wrote:
I think the crux of this is whether the idea of merging Berkeley
into LowRISC is realistic or not.. it seems like a very large amount of
work? Do I have that right? For example, might it even be easier be to
simply restart with the current Rocket repo and redo the integration
work, rather then trying to weed through all the merge conflicts..? Or,
do I misunderstand the effort involved?
I think Wei can best comment on this. The major addition of lowRISC is
Tagged Memory and I agree the better approach is to rebase that work.
Beside that it is actually TL2 that remains.
If that is the case, that the effort of a merge is prohibitive, and
result LowRISC never actually merge Berkeley code back in, then we would
be fine.. we port TL2 once, and then mainstream it into LowRISC, and
there's no more effort after that. At least as long as that version is
good enough, then there is no strong reason to update it.
For now its every privilege spec update that needs to be implemented,
possibly further extensions if wanted. Then run-control debug and
probably other stuff I am not even aware of.
Has there been any discussion about the likelihood and timing of
updating LowRISC to the new Berkeley style of things? We have some
evidence that the new Berkeley style is less modular, and has a steeper
learning curve than the July 2016 version of the code. We chose LowRISC
in part for this reason -- the older style is simpler, easier for us to
get up and running.
Yeah, I agree on the learning curve issue, but am personally undecided
if that is a good enough reason to permanently divert.
Have a great weekend!