On Wed, 31 Oct 2012 16:26:54 +0100 Daniel Vetter <daniel at ffwll.ch> wrote: > On Wed, Oct 31, 2012 at 4:23 PM, Jesse Barnes <jbarnes at virtuousgeek.org> wrote: > > > >> On Tue, Oct 30, 2012 at 01:33:47PM -0500, Jesse Barnes wrote: > >> > The hw supports async flips through the render ring, so why not expose it? > >> > It gives us one more "tear me harder" option we can use in the DDX and > >> > for other cases where simply flipping to the latest buffer is more > >> > important than visual quality. > >> > >> The only reason I can see why anyone would really want async flips is > >> when you're restricted to double buffering. With triple buffering you > >> should be able to override the previous flip w/o tearing. > >> > >> Well, actually if you use the ring based flips, then you can't do the > >> override. My atomic page flip code can do it because it's using mmio > >> flips. There were also other reasons favoring mmio over ring. > >> > >> Once the atomic code is deemed ready, I would suggest we just nuke the > >> ring based flip code (pun intended). > > > > Yeah, I agree. In fact one of the first versions of the flip code used > > mmio, and I think it's a better way to go. > > How are we gonna sync up with outstanding rendering before issuing the > flip? If the answer is involves enabling the render irq, I'm not gonna > like it ;-) Why are you afraid of irqs when rendering is active? We'll already be awake at those times anyway... -- Jesse Barnes, Intel Open Source Technology Center
