On Tue, May 11, 2021 at 05:55:12PM +0200, Maxime Ripard wrote: > New KMS properties come with a bunch of requirements to avoid each > driver from running their own, inconsistent, set of properties, > eventually leading to issues like property conflicts, inconsistencies > between drivers and semantics, etc. > > Let's document what we expect. > > Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> > --- > Documentation/gpu/drm-kms.rst | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst > index 87e5023e3f55..30f4c376f419 100644 > --- a/Documentation/gpu/drm-kms.rst > +++ b/Documentation/gpu/drm-kms.rst > @@ -463,6 +463,24 @@ KMS Properties > This section of the documentation is primarily aimed at user-space developers. > For the driver APIs, see the other sections. > > +Requirements > +------------ > + > +KMS drivers might need to add extra properties to support new features. > +Each new property introduced in a driver need to meet a few > +requirements, in addition to the one mentioned above.: > + > +- It must be standardized, with some documentation to describe the > + property can be used. > + > +- It must provide a generic helper in the core code to register that > + property on the object it attaches to. Maybe also include anything that drivers might want to precompute, e.g. we have helpers for cliprects. > + > +- Its content must be decoded by the core and provided in the object object's > + associated state structure. > + > +- An IGT test must be submitted. "... where reasonable." We have that disclaimer already here: https://dri.freedesktop.org/docs/drm/gpu/drm-uapi.html#testing-requirements-for-userspace-api I think would be good to cross-reference the uapi rules in general https://dri.freedesktop.org/docs/drm/gpu/drm-uapi.html#open-source-userspace-requirements With the bikesheds addressed: Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> But this needs ideally a pile of acks from most display driver teams. -Daniel > + > Property Types and Blob Property Support > ---------------------------------------- > > -- > 2.31.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
