mesa, intel driver, and synchronous flipping

Michel Dänzer michel at
Wed Dec 17 01:59:08 PST 2008

On Wed, 2008-12-17 at 18:11 +1100, garrone wrote:
> The mesa direct rendering with the intel driver appears to rely on
> asychronous flipping. However the hardware, according to the 965
> documentation I have downloaded from the intellinuxgraphics site, is
> capable of synchronous flips. 
> (The kernel file i915_dma.c ors in the "ASYNC_FLIP" constant in the function
> i915_dispatch_flip, invoked eventually by a call to glXSwapBuffers.
> For a description of the hardware capability, 
> refer to volume 1 of the 965 graphics pdf files, searching for the
> command MI_DISPLAY_FLIP)
> The application I am targeting has dual opengl windows, 
> each one running on a separate display, and covering the whole of that
> display, from a single Intel graphics chipset.

This was working with synchronous flips at some point at least on
i915/i945 hardware, but I think the functionality has been ripped out
again because GEM didn't mix well with it.

Earthling Michel Dänzer           |
Libre software enthusiast         |          Debian, X and DRI developer

More information about the xorg mailing list