[PATCH 2/2] drm/panfrost: adjusted job affinity for dual core group GPUs

[Alexey Sheplyakov]

Hi, Alyssa,

On Mon, Jan 10, 2022 at 12:42:44PM -0500, Alyssa Rosenzweig wrote:
> > Whether it's worth the effort depends on whether anyone really cares
> > about getting the full performance out of this particular GPU.
> > 
> > At this stage I think the main UABI change would be to add the opposite
> > flag to kbase, (e.g. "PANFROST_JD_DOESNT_NEED_COHERENCY_ON_GPU"[1]) to
> > opt-in to allowing the job to run across all cores.
> > 
> > The second change would be to allow compute jobs to be run on the second
> > core group, so another flag: PANFROST_RUN_ON_SECOND_CORE_GROUP.
> > 
> > But clearly there's little point adding such flags until someone steps
> > up to do the Mesa work.
> 
> I worry about the maintainence burden (both Mesa and kernel) of adding
> UABI only used by a piece of hardware none of us own, and only useful

To solve the "no hardware" problem we can send you (or any interested
panfrost hacker) a BE-M1000 based board (for free). BE-M1000 is 8 core
armv8 (Cortex A53) SoC with Mali T628 GPU. Plese email me for the further
details (preferably off the list) if you are interested.

Best regards,
   Alexey