Nouveau - Feb 2021 - [PATCH 2/3] drm/nouveau/kms/nv50-: Report max cursor size to userspace

Ilia Mirkin, Wed, Feb 24, 2021 16:10:57 +0100:
> On Wed, Feb 24, 2021 at 4:09 AM Alex Riesen <alexander.riesen at
cetitec.com> wrote:
> > Ilia Mirkin, Tue, Feb 23, 2021 19:13:59 +0100:
> > > It might also be worthwhile just testing if the 256x256 cursor
works
> > > quite the way one would want. If you're interested, grab
libdrm,
> > > there's a test called 'modetest', which has an option
to enable a
> > > moving cursor (-c iirc). It's hard-coded to 64x64, so
you'll have to
> > > modify it there too (and probably change the pattern from plain
gray
> > > to any one of the other ones).
> >
> > I am interested, so I did.
> >
> > If I start the test without X running, the sprite of 256x256 cursor
always
> > contained horizontal lines across it, both with commit reverted and
vanilla
> > v5.11. Similarly, the 64x64 cursor has no lines across it in both
kernels.
> >
> > The test does not seem to work at all if there is an X server running
(using
> > modesetting driver): modetest complained about permission denied to
set the
> > mode, and just sits there, drawing nothing on the displays.
> > So I could not run the test in the environment of original problem.
> > Am I starting it correctly? Is the change in modetest.c correct?
> 
> Looks right. Although TBH I'd just start it on a single display (I
> forgot you could even do multiple displays). You should be able to
> start it with the X server running if you switch to a vt (and run it
> as root). If you can't, that means the modesetting driver is
> forgetting to do something in the LeaveVT function.
Tried that and yes, modetest works. Even without running it as root.
> The fact that you're getting lines with modetest means there's
> something wrong with 256x256. What if you do 128x128 -- does that work
> OK?
Yes. Unfortunately in both cases.
> Simon, you tested on a GK208, that has a slightly later display
> controller than the GK104 -- can you try to reproduce Alex's results?
> Perhaps there was a problem with the GK10x's and it starts working OK
> with the GK110 disp.
> 
> I don't have any GK10x's in my posession (I have nearly every other
> iteration of the display controller), but hopefully someone on the
> nouveau team will be able to dig one up and reproduce.
> 
> Thanks for testing, Alex!
You're welcome! As I'm stuck with this particular machine for
foreseeable
future, you can count on mine GK10x as well.

On Wed, Feb 24, 2021 at 11:35 AM Alex Riesen
<alexander.riesen at cetitec.com> wrote:
> Ilia Mirkin, Wed, Feb 24, 2021 16:10:57 +0100:
> > The fact that you're getting lines with modetest means there's
> > something wrong with 256x256. What if you do 128x128 -- does that work
> > OK?
>
> Yes. Unfortunately in both cases.
Just to be crystal clear -- are you saying that 128x128 works or does
not work? (You said "yes", which would imply it works OK, but then you
said both cases, which would imply doesn't work since 256x256 doesn't
work?)

Thanks,

  -ilia