[virglrenderer-devel] coherent memory access for virgl

[Gerd Hoffmann]

  Hi,

> > > For example, on some ARM devices, AFBC can be only used on the (host)
> > > primary KMS plane.
> >
> > What is AFBC?  Some drm format modifier?
> 
> Yes, it stands for ARM frame buffer compression and it's widely used
> on that architecture.

Speaking of compression:  How does buffer size calculation and buffer
allocation work in case compression is used?

> Speaking of reallocation, the current Linux modifier API
> (gbm_bo_create_with_modifiers) passes in a list of supported modifiers
> for gbm to allocate from.  Assuming we do think of a way to notify the
> guest about the available KMS-supported modifiers, any new allocation
> ioctl will probably need to pass the modifier list to the host.

How does mesa handle modifiers?  Does it use the drm modifiers directly?
Or has mesa/gallium its own naming scheme?

Right now the format specification used by virtio is based on gallium
formats ...

cheers,
  Gerd