FB model basic issues (WAS: radeon, apertures & memory mapping)

[Benjamin Herrenschmidt]

On Thu, 2005-03-17 at 03:25 +0200, Ville Syrjälä wrote:
> On Thu, Mar 17, 2005 at 12:12:58PM +1100, Benjamin Herrenschmidt wrote:
> > 
> > > I understand you can't have userspace program the accelerator while 
> > > someone else is doing the same thing. Oh and I now understand that the 
> > > same really applies to direct framebuffer access due to the swapper.  
> > 
> > And you can't have someone program the accelerator while somebody does
> > direct access neither. It's basically all exclusive.
> 
> I haven't seen that happen on any hardware I own. Matrox specs explicitly 
> mention that there is no need to synchronize accelerator and direct 
> framebuffer access.

You are lucky then :)

Ben.