[ECOS] MPC860, MSR initialization

Gary Thomas gary@mlbassoc.com
Wed Mar 5 05:47:00 GMT 2003

On Tue, 2003-03-04 at 18:57, Jonathan Larmour wrote:
> Radu Cernea wrote:
> > Hi,
> >  
> > I think there is a small problem with the definition CYG_MSR_COMMON in the file 
> > 
> > …\hal\powerpc\arch\current\src\vectors.S 
> > 
> > The FP bit should not be asserted for MPC860. See MPC860UM, chapter
> True. Below patch checked in.

While this is true, pedantically, it doesn't seem to matter at all
for any MPC8xx that we've ever run eCos on (and it's been nearly 5 years
now).  The patch does make things match the documentation, even if
"real life experience" does not :-)

Note: I checked this and it has no performance difference at all.
My guess is that the bit is simply ignored by the hardware.

Gary Thomas                 |
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