On Wed, 26 Jun 2024 at 18:52, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Wed, Jun 26, 2024 at 11:39:01AM +0100, Daniel Stone wrote: > > On Wed, 26 Jun 2024 at 09:28, Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote: > > > So we are kind of stuck here between breaking one or the other use- > > > case. I'm leaning heavily into the direction of just fixing Mesa, so we > > > can specify the type of screen we need at creation time to avoid the > > > renderonly issue, porting this change as far back as reasonably > > > possible and file old userspace into shit-happens. > > > > Yeah, honestly this sounds like the best solution to me too. > > Yeah mesa sounds kinda broken here ... > > What might work in the kernel is if you publish a fake 3d engine that's > too new for broken mesa, if that's enough to make it fail to bind? And if > mesa still happily binds against that, then yeah it's probably too broken > and we need etnaviv-v2 (as a drm driver uapi name, I think that's what > mesa filters?) for anything new (including the NN-only ones). > > I would still try to avoid that, but just in case someone screams about > regressions. It's not just etnaviv, it's literally every Mesa driver which works with decoupled render/display. So that would be etnaviv-v2, panfrost-v2, panthor-v2, v3d-v2, powervr-v2, ... albeit those don't tend to have multiple instances. Anyway, I'm still leaning towards the answer being: this is not an etnaviv regression caused by NPU, it's a longstanding generic Mesa issue for which the answer is to fix the known fragility. Cheers, Daniel
