Masami and Ken Nakata wrote:
> > in grf.c:
> > 374c374
> > <     *addrp += (unsigned long) gp->sc_grfmode->fboff & 0xfff;
> > ---
> > >     *addrp += (unsigned long) gp->sc_grfmode->fboff;
> 
> But I'm not sure of this one.  I vaguely remember this is necessary on
> some (old, I think) models (probably those with 32-bit dirty ROM).

  Thats what I thought at first too: the SE/30 fboff was 0x8000,
which looks a lot like a flag bit, and the SE/30 has dirty ROMs.
However I've concluded that the offset really is 32767. It has two
banks of video RAM, seperated by 32K, and the primary bank is the
upper one.

  I believe that most machines must have an fboff of zero,
because I don't see how mmap() of /dev/grf could work otherwise.