On 10/03, Daniel Vetter wrote: > Typed up all the items Rodrigo capture at the vkms workshop at > xdc2018: > > https://etherpad.net/p/vkms_todo > > v2: Review from Rodrigo. > - Add eBPF for atomic check, I forgot it. > - Improve spelling. > > Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> > Cc: Gustavo Padovan <gustavo@xxxxxxxxxxx> > Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> > Cc: Sean Paul <sean@xxxxxxxxxx> > Cc: Haneen Mohammed <hamohammed.sa@xxxxxxxxx> > Cc: Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx> > --- > Documentation/gpu/vkms.rst | 101 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 99 insertions(+), 2 deletions(-) > > diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst > index 0a6ea6216e41..7dfc349a4508 100644 > --- a/Documentation/gpu/vkms.rst > +++ b/Documentation/gpu/vkms.rst > @@ -10,8 +10,8 @@ > TODO > ==== > > -CRC API > -------- > +CRC API Improvements > +-------------------- > > - Optimize CRC computation ``compute_crc()`` and plane blending ``blend()`` > > @@ -22,3 +22,100 @@ CRC API > > - Add igt test to check extreme alpha values i.e. fully opaque and fully > transparent (intermediate values are affected by hw-specific rounding modes). > + > +Vblank issues > +------------- > + > +Some IGT test cases are failing. Need to analyze why and fix the issues: > + > +- plain-flip-fb-recreate > +- plain-flip-ts-check > +- flip-vs-blocking-wf-vblank > +- plain-flip-fb-recreate-interruptible > +- flip-vs-wf_vblank-interruptible > + > +Runtime Configuration > +--------------------- > + > +We want to be able to reconfigure vkms instance without having to reload the > +module. Use/Test-cases: > + > +- Hotplug/hotremove connectors on the fly (to be able to test DP MST handling of > + compositors). > + > +- Configure planes/crtcs/connectors (we'd need some code to have more than 1 of > + them first). > + > +- Change output configuration: Plug/unplug screens, change EDID, allow changing > + the refresh rate. > + > +The currently proposed solution is to expose vkms configuration through > +configfs. All existing module options should be supported through configfs too. > + > +Add Plane Features > +------------------ > + > +There's lots of plane features we could add support for: > + > +- Real overlay planes, not just cursor. > + > +- Full alpha blending on all planes. > + > +- Rotation, scaling. > + > +- Additional buffer formats, especially YUV formats for video like NV12. > + Low/high bpp RGB formats would also be interesting. > + > +- Async updates (currently only possible on cursor plane using the legacy cursor > + api). > + > +For all of these, we also want to review the igt test coverage and make sure all > +relevant igt testcases work on vkms. > + > +Writeback support > +----------------- > + > +Currently vkms only computes a CRC for each frame. Once we have additional plane > +features, we could write back the entire composited frame, and expose it as: > + > +- Writeback connector. This is useful for testing compositors if you don't have > + hardware with writeback support. > + > +- As a v4l device. This is useful for debugging compositors on special vkms > + configurations, so that developers see what's really going on. > + > +Prime Buffer Sharing > +-------------------- > + > +We already have vgem, which is a gem driver for testing rendering, similar to > +how vkms is for testing the modeset side. Adding buffer sharing support to vkms > +allows us to test them together, to test synchronization and lots of other > +features. Also, this allows compositors to test whether they work correctly on > +SoC chips, where the display and rendering is very often split between 2 > +drivers. > + > +Output Features > +--------------- > + > +- Variable refresh rate/freesync support. This probably needs prime buffer > + sharing support, so that we can use vgem fences to simulate rendering in > + testing. Also needs support to specify the EDID. > + > +- Add support for link status, so that compositors can validate their runtime > + fallbacks when e.g. a Display Port link goes bad. > + > +- All the hotplug handling describe under "Runtime Configuration". > + > +Atomic Check using eBPF > +----------------------- > + > +Atomic drivers have lots of restrictions which are not exposed to userspace in > +any explicit form through e.g. possible property values. Userspace can only > +inquiry about these limits through the atomic IOCTL, possibly using the > +TEST_ONLY flag. Trying to add configurable code for all these limits, to allow > +compositors to be tested against them, would be rather futile exercise. Instead > +we could add support for eBPF to validate any kind of atomic state, and > +implement a library of different restrictions. > + > +This needs a bunch of features (plane compositing, multiple outputs, ...) > +enabled already to make sense. > -- > 2.19.0.rc2 > Reviewed-by: Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx> -- Rodrigo Siqueira http://siqueira.tech Graduate Student Department of Computer Science University of São Paulo _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
