From: Sengan Baring-Gould <sengan@seqnet.net>
  To  : ggi-develop@eskimo.com
  Date: Tue, 25 Aug 1998 19:09:27 -0600

UMA problem

When running xf68_dev I noticed that it appeared
to be writing into the compression buffer which is
stored after the uncompressed frame buffer on the
MediaGX... which of course screws things up nicely.

In general games might want to store data in the space
between the end of the used screen memory and
fb_fix_screeninfo.smem_start+smem_len... which will
cause badness on the MediaGX.

So I need to be able to tell the fb device that the
framebuffer just changed size... or at least prevent
the memmapping to take over the whole memory
space.

In general this problem should occur with all devices
using a unified memory architecture, so I'm not quite
sure why fbcon does not allow it (the old amiga had UMA
and screens of varying sizes for instance)

What should I do?

Sengan