The following URL link shows 6 parts article series about a
certain
computer built upon AMCC 405GPr.  It's a very good reading
for general public, 
I believe.

h
ttp://www-128.ibm.com/developerworks/views/power/libraryview
.jsp?search_by=Testing+and+measuring+the+TAMS+3011

... excerpt of Part 5 ...
The TAMS 3011 system this series uses is built around the
AMCC PowerPC
405GPr,
... Having looked at Linux and eCos on the 3011, this series
turns now to the
NetBSD port to it.
... NetBSD runs on other systems based on the 405GPr chip,
and the chip's
architecture turns out to make the port a comparatively
simple task.

... from an inset column ...
Of course it runs NetBSD
Why NetBSD? It's a system with clean, portable code, and it
makes a good
environment for exploring the system. ... Because NetBSD
runs on a very broad 
range of hardware, some of it
fairly slow, NetBSD also has excellent support for
cross-compilation.
While using a faster system to compile for a slower system
is appealing,
this is also a very handy thing when targeting a new board.
The
well-supported cross-development tools save a lot of time. 
Toru Nishimura / ALKYL Technology