[igt-dev] [Intel-gfx] [PATCH i-g-t v2 03/14] lib/igt_kms: Rework pipe properties to be more atomic, v7.

[Daniel Vetter]

On Mon, Mar 05, 2018 at 03:37:30PM +0100, Maxime Ripard wrote:
> Hi,
> 
> On Thu, Oct 12, 2017 at 01:54:24PM +0200, Maarten Lankhorst wrote:
> > In the future I want to allow tests to commit more properties,
> > but for this to work I have to fix all properties to work better
> > with atomic commit. Instead of special casing each
> > property make a bitmask for all property changed flags, and try to
> > commit all properties.
> > 
> > This has been the most involved one, since legacy pipe commit still
> > handles a lot of the properties differently from the rest.
> > 
> > Changes since v1:
> > - Dump all changed properties on commit.
> > - Fix bug in igt_pipe_refresh().
> > Changes since v2:
> > - Set pipe ACTIVE property changed flag on init.
> > Changes since v3:
> > - Add a missing igt_pipe_refresh() to kms_atomic_interruptible.
> > Changes since v4:
> > - Perform error handling when setting custom crtc properties.
> > Changes since v5:
> > - Only attempt to commit changes properties.
> > Changes since v6:
> > - Clear OUT_FENCE_PTR on succesful commit.
> > 
> > Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> 
> I'm a bit late to the party on this one, but this commit broke the
> chamelium tests on vc4, with every kernel since at least 4.12.
> 
> This is the error message:
> http://code.bulix.org/32fw1l-293842
> 
> From the stack trace, it looks like the atomic commit was failing, and
> indeed it fails here:
> https://elixir.bootlin.com/linux/v4.16-rc4/source/drivers/gpu/drm/drm_atomic.c#L2319
> 
> with prop_id being 0 for some reason.
> 
> I had a look at that patch, but I can't see anything wrong with it. Do
> you have any ideas?

No idea tbh, I guess we need to start tracing where the igt library tries
to set property 0. Would probably be really good to catch that in the
libdrm atomic support (same with trying to set a prop on obj 0, neither
makes any sense at all).
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch