Subject: Re: Xorg on Fujitsu "Lime" with MPC5200b?

From: Anatolij Gustschin <[email-masked]>
Date: Thu, 15 Apr 2010 09:44:13 +0200

On Wed, 14 Apr 2010 22:07:08 -0500
Bill Gatliff <[email-masked]> wrote:

> Put simply, I have an MPC5200b platform with a Fujitsu "Lime" GDC, and
> I'm trying to run Debian squeeze's xorg on it.
> 
> Actually, I *have* Debian squeeze's xorg running on the platform just
> fine, with a 2.6.34-rc1 kernel (kernel.org).  Problem is, every single
> diagonal line is very blocky--- not smooth at all.  I used to think this
> was a problem with X's fonts, but now I don't think so because the mouse
> cursor's diagonal lines also look equally bad.
> 
> It's almost as if any time the platform tries to draw a diagonal line,
> truncation/rounding errors are causing it problems in figuring out which
> pixels to turn on and off.

On all PowerPC based boards with Lime (PPC440EPx, MPC85xx) I have seen so
far there is a similar problem with direct access to the frame buffer in
16-bit mode.

> A non-Linux kernel on this hardware, running a non-X GUI, seems to work
> fine so I think the hardware isn't the problem.

It is possible that this non-X GUI doesn't access the frame buffer directly
but only uses the accelerated driver for rendering. In this case all
drawing is done by Lime itself triggered by 32-bit accesses to the
drawing command FIFO.

> Anyone have any suggestions on where to start with this one?  Anyone
> else running a similar configuration with any success?  I'm completely
> lost, and running out of hair *fast*...

You probably have to fix Xorg driver for swapping.

Anatolij