dri/drm/kms question with regards to minor faults

[Bert Schiettecatte]

Hi John 

> Coincidentally, I've been looking at Panfrost on RK3288 this week as
> well!  I'm testing it with a project that has been using the binary blob
> driver for several years and unfortunately Panfrost seems to use ~15%
> more CPU.
> Like you, I see a huge number of minor faults (~500/second compared with
> ~3/second on libmali).  It seems that Panfrost is mmap'ing and
> munmap'ing buffers on every frame which doesn't happen when the same
> application is using the binary driver.

Thanks for confirming you are seeing the same issue. 

> Panfrost experts, is there a missed opportunity for optimisation here?
> Or is there something applications should be doing differently to avoid
> repeatedly mapping & unmapping the same buffers?

Panfrost team - any update on this? 

Thanks
Bert