On Wed, Feb 22, 2012 at 04:03:21PM +0000, James Simmons wrote: > > > > Imo we should ditch this - fb accel doesn't belong into the kernel. Even > > > on hw that still has a blitter for easy 2d accel without a complete 3d > > > state setup necessary, it's not worth it. Chris Wilson from our team once > > > played around with implementing fb accel in the kernel (i915 hw still has > > > a blitter engine in the latest generations). He quickly noticed that to > > > have decent speed, competitive with s/w rendering by the cpu he needs the > > > entire batch and buffer management stuff from userspace. And to really > > > beat the cpu, you need even more magic. > > > > > > If you want fast 2d accel, use something like cairo. > > > > Our conclusion on this is that we should not expose an explicit 2D > > acceleration API at the kernel level. If really needed, hardware 2D > > acceleration could be implemented as a DRM device to handle memory management, > > commands ring setup, synchronization, ... but I'm not even sure if that's > > worth it. I might not have conveyed it well in my notes. > > Fbcon scrolling at be painful at HD or better modes. Fbcon needs 3 > possible accels; copyarea, imageblit, and fillrect. The first two could be > hooked from the TTM layer. Its something I plan to experiment to see if > its worth it. Let's bite into this ;-) I know that fbcon scrolling totally sucks on big screens, but I also think it's a total waste of time to fix this. Imo fbcon has 2 use-cases: - display an OOSP. - allow me to run fsck (or any other desaster-recovery stuff). It can do that quite fine already. Flamy yours, Daniel -- Daniel Vetter Mail: daniel@xxxxxxxx Mobile: +41 (0)79 365 57 48 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
