On Sat, Oct 23, 2010 at 1:22 PM, Patrick McNamara <[email protected]> wrote: > As it currently sits, the framebuffer driver is decent enough with the > exception of full screen scrolling. That is very painful.
This is in part because PCI reads take about 4x as long as writes. The writes get combined into bursts (MTRR setting), while reads are separate transactions. A dirty fix for this would be to avoid PCI reads entirely. It would be cool if we could somehow get fb to write to the card and to a local buffer, while doing all reads from the local buffer. We could do this by wrapping every fb call or somehow using XAA, EXA, or UXA and just making all the right fb calls. Anything that does writes would get called twice, once for the back buffer, once for the screen. All reads would always be directed at the back buffer. -- Timothy Normand Miller http://www.cse.ohio-state.edu/~millerti Open Graphics Project _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
