briggs@puma.macbsd.com wrote:
> 
> > However, there is no routine to do this on the 68040 class of
> > machines (at least there wasn't pre 1.2 - has anything changed?),
> > and NetBSD assumes it's contiguous. When the MMU is disabled, it
> > crashes.
> 
> The memory layout of the IIci and IIsi differ only in that the IIsi has
> 1MB soldered into bank A whereas the IIci has 4 SIMM slots for bank A.
> 
> Scott has written a routine that should allow the 040 to get the mapping
> info.  It's in -current (not in 1.2 or earlier sources).  I haven't
> tried it, yet.  You may have to enable it in pmap_bootstrap.c.

Hmm... looks like it's time to upgrade my kernel sources (for a start,
anyway).

> > > 1)  What does the FPSP compile option do?  040 floating point software?
> > >     Do I need this to use an 040 CPU?
> >
> > This is only required if your Daystar is a "light" 040 with no FPU,
> > ie. a 68LC040.
> 
> Nope.  You need FPU_EMULATE if you have an LC040.  If you have a full
> 040, you need FPSP because it emulates instructions that were in the
> 68881 and 68882 but not in the FPU on the 040.

Whoops - I stand corrected (thanks, Allen). I forgot about the striped
down FPU in the '040. Teaches me not to answer questions without first
investigating...

-- 
Paul Ripke
BHP Information Technology
Open VMS, AXP & UNIX (AIX, HP/UX, DG/UX, SCO, SGI, Digital, SunOS...) Sysadmin
Computer Centre,    Five Islands Rd,    Port Kembla,    NSW 2505,    AUSTRALIA
  ripke.paul.pr@bhp.com.au     weripp@itwol.bhp.com.au     pjr02@uow.edu.au
            Anyone wishing to lay claim to the opinions expressed
                      herein, do so at their own risk.