FreeBSD support this hardware?

[Ted Mittelstaedt]

> -----Original Message-----
> From: owner-freebsd-questions at freebsd.org
> [mailto:owner-freebsd-questions at freebsd.org]On Behalf Of Ivan Voras
> Sent: Thursday, February 28, 2008 3:30 AM
> To: freebsd-questions at freebsd.org
> Subject: Re: FreeBSD support this hardware?
> 
> 
> Robe wrote:
> 
> > And here's the link to the CPU page 
> http://www.dmp.com.tw/tech/Vortex86SX/
> > 
> > Can anybody tell me if FreeBSD support this hardware?
> 
> Judging by the "SX" label and the information on the page, no, because
> it doesn't have a FPU.
> 

I'm surprised they claim Linux compatability since
I thought Linux required an FPU as well.

FreeBSD 4.X supports these with the kernel option
MATH_EMULATE or GPL_MATH_EMULATE  Later versions of
FreeBSD got rid of that option.

NetBSD 4 still has MATH_EMULATE but it's buggy.  There
was a discussion last month on the NetBSD mailing
list about whether it would be a good thing to fix it.

You could, possibly, recompile FreeBSD (or more
likely, picobsd, see "man picobsd" for information)
with the -msoft-float option to gcc to build a version
that would not require a FPU.   But you still need
an emulator that would supply the floating point
operations. gcc includes (or included) a generic
implementation of these functions in dp-bit.c and
fp-bit.c.  Of course, it would be under the GPL.
Or you could get the FreeBSD 4.11 source and dig up
the ancient emulator that was under the BSD license
and use that.

Here's a thread fragment I found that discusses the
process with regards to building libgcc 
http://www.busybox.net/lists/uclibc/2002-May/003404.html

Good luck - some things are better off left dead,
the non-FPU cpus were one of these things.

Ted