Re: Habanalabs Open-Source TPC LLVM compiler and SynapseAI Core library

From: Daniel Vetter <daniel.vetter@ffwll.ch>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Oded Gabbay <ogabbay@kernel.org>,
	mzuckerman@habana.ai, dsinger@habana.ai,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Dave Airlie <airlied@gmail.com>, Jason Gunthorpe <jgg@ziepe.ca>,
	"Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>
Subject: Re: Habanalabs Open-Source TPC LLVM compiler and SynapseAI Core library
Date: Fri, 10 Sep 2021 18:09:51 +0200	[thread overview]
Message-ID: <CAKMK7uFLBmdHphtnEa1nyAGUHdcP1KgmaK+vtV_GOU6wZZAOxg@mail.gmail.com> (raw)
In-Reply-To: <YTsQJ753sm701R/n@kroah.com>

On Fri, Sep 10, 2021 at 9:58 AM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
> On Fri, Sep 10, 2021 at 10:26:56AM +0300, Oded Gabbay wrote:
> > Hi Greg,
> >
> > Following our conversations a couple of months ago, I'm happy to tell you that
> > Habanalabs has open-sourced its TPC (Tensor Processing Core) LLVM compiler,
> > which is a fork of the LLVM open-source project.
> >
> > The project can be found on Habanalabs GitHub website at:
> > https://github.com/HabanaAI/tpc_llvm
> >
> > There is a companion guide on how to write TPC kernels at:
> > https://docs.habana.ai/en/latest/TPC_User_Guide/TPC_User_Guide.html
>
> That's great news, thanks for pushing for this and releasing it all!

Yeah this is neat.

There's still the problem that we spent the past 2.5 years pissing off
a lot of people for an imo questionable political project, bypassing
all the technical review and expertise. Now that the political
nonsense is resolved I think we need to look at at least the technical
cleanup. The angered people are much harder to fix, so let's maybe
ignore that (or perhaps a ks topic, no idea, I'm honestly not super
motivated to rehash this entire story again). Here's what I think we
should do:

- move drivers/misc/habanalabs under drivers/gpu/habanalabs and
review/discussions on dri-devel
- grandfather the entire current situation in as-is, it's not the only
driver we have with a funny uapi of its own (but the other driver did
manage to get their compiler into upstream llvm even, and not like 2
years late)
- review the dma-buf stuff on dri-devel and then land it through
standard flows, not the gregk-misc bypass
- close drivers/misc backdoor for further accel driver submissions,
I'd like to focus on technical stuff in this area going forward and
not pointless exercises in bypassing due process and all that

I expect we'll have a proper discussion what the stack should look
like with the next submission (from a different vendor maybe), that
ship kinda sailed with habanalabs.

Cheers, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch