Re: [PATCH] drm/fourcc: document modifier uniqueness requirements

2020-06-02 Thread Daniel Vetter
On Mon, Jun 01, 2020 at 11:35:54AM +0100, Brian Starkey wrote: > On Wed, May 27, 2020 at 10:55:34AM +0200, Daniel Vetter wrote: > > On Wed, May 27, 2020 at 08:52:00AM +, Simon Ser wrote: > > > There have suggestions to bake pitch alignment, address alignement, > > > contiguous memory or other p

Re: [PATCH] drm/fourcc: document modifier uniqueness requirements

2020-06-01 Thread Simon Ser
> > > + * Users see modifiers as opaque tokens they can check for equality and > > > + * intersect. Users musn't need to know to reason about the modifier > > > value > > > + * (i.e. users are not expected to extract information out of the > > > modifier). > > > + * > > Doesn't this conflict with

Re: [PATCH] drm/fourcc: document modifier uniqueness requirements

2020-06-01 Thread Brian Starkey
On Wed, May 27, 2020 at 10:55:34AM +0200, Daniel Vetter wrote: > On Wed, May 27, 2020 at 08:52:00AM +, Simon Ser wrote: > > There have suggestions to bake pitch alignment, address alignement, > > contiguous memory or other placement (hidden VRAM, GTT/BAR, etc) > > constraints into modifiers. La

Re: [PATCH] drm/fourcc: document modifier uniqueness requirements

2020-05-27 Thread Daniel Vetter
On Wed, May 27, 2020 at 08:52:00AM +, Simon Ser wrote: > There have suggestions to bake pitch alignment, address alignement, > contiguous memory or other placement (hidden VRAM, GTT/BAR, etc) > constraints into modifiers. Last time this was brought up it seemed > like the consensus was to not a

[PATCH] drm/fourcc: document modifier uniqueness requirements

2020-05-27 Thread Simon Ser
There have suggestions to bake pitch alignment, address alignement, contiguous memory or other placement (hidden VRAM, GTT/BAR, etc) constraints into modifiers. Last time this was brought up it seemed like the consensus was to not allow this. Document this in drm_fourcc.h. There are several reason