Hi,
> > > > + msg->vram.user_ctx = msg->vram.vram_gpa = vram_pp;
> > > > + msg->vram.is_vram_gpa_specified = 1;
> > > > + synthvid_send(hdev, msg);
> > >
> > > That suggests it is possible to define multiple framebuffers in vram,
> > > then pageflip by setting vram.vram_gpa. If that is the case I'm
> > > wondering whenever vram helpers are a better fit maybe? You don't
> > > have
> > > to blit each and every display update then.
> >
> > Thanks for the review. Unfortunately only the first vmbus message take
> > effect and subsequent calls are ignored. I originally implemented using
> > vram helpers but I figured out calling this vmbus message again won't
> > change the vram location.
/me notices there also is user_ctx. What is this?
> I think that needs a very big comment. Maybe even enforce that with a
> "vram_gpa_set" boolean in the device structure, and complain if we try to
> do that twice.
>
> Also I guess congrats to microsoft for defining things like that :-/
I would be kind of surprised if the virtual device doesn't support
pageflips. Maybe setting vram_gpa just isn't the correct way to do
it. Is there a specification available?
There are a number of microsoft folks in Cc: Anyone willing to comment?
thanks,
Gerd
PS: And, yes, in case pageflips really don't work going with shmem
helpers + blits is reasonable.
