Hi,
I am working on a concept terminal that required the LCD display to
be running X windows in portrait mode (600x800). At the moment,
the approach that I have taken is to take the standard vesafb driver
(the system has VESA BIOS support) and allocate a block of memory
to use as a portrait framebuffer. Then I used a kernel thread running
in the background to copy from this virtual framebuffer to the physical
framebuffer (which is in landscape) at regular interval. I ran the
standard XF86_FBDev on top of this and it recognizes the framebuffer
correctly and run the X windows in portrait mode.
Here's the problem: the copying from one buffer to the other is taking
up lots of CPU time (about 30% or more), this causes deteriotion of
the system performance. I believe I have already optimized the code
substantiately, but the performance still not up to what we want (when
we move our stylus on the touch screen at normal handwriting speed,
the cursor always trails behind).
Does anyone know what else I can try to get a better performance out
of the system? Some people did told me that I should modify the X
windows
directly to have better performance, but I am quite reluctant due to
the complexity and lack of understanding of X server itself. I would
be gladful if someone could do that or guide me on doing it.
Thanks a lot!
Regards,
T J
-- Chng Tiak-Jung tiak-jung.chng@ericsson.com Ericsson Research/Cyberlab Singapore Tel: +65-350-1649 510 Thomson Road, #18-00 Fax: +65-256-2403 SLF Building, Singapore 298135 http://www.ericsson.com/- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Thu Mar 23 2000 - 21:00:22 EST