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[MiNT] FPU question

Hi,

I have a question regarding memory mapped FPU's in 68000 machines (e.g.
MegaSTE): how does the _FPU cookie look like on such a machine?

This is important for making MiNT hardware FPU test working right. The
point is:

1) MiNT relies on a presence of a `true FPU' in the machine. This
   information is needed to save and restore FPU state at context
   switches.

2) An internal FPU in 68060 and 68040, as well as 68882 attached to a
   68020/68030 in coprocessor mode make no problems here.

3) But 68000 has no coprocessor mode, thus a memory mapped FPU has to be
   handled via Line-F handler (correct me if I am wrong).

4) However, MiNT itself does not install Line-F FPU emulation, and
   to my knowledge, doesn't pass Line-F exceptions to the TOS.

So, I am afraid, if the FPU detection routine tells the kernel, that
a memory mapped FPU is a `true coprocessor', the kernel will generate a
'11 bombs' signal at next context switch after attempt to do a FSAVE.

If the FPU detection routine tells the kernel, that there's no FPU (though
a memory mapped 68881 may exist), no _FPU cookie will be present. This is
true though, because indicates that no Line-F routines are installed, so
infomation about such an FPU would be useless.

I am puzzled at the moment, so please tell me someone: how does the _FPU
cookie look like on a 68000 MegaSTE equipped with an FPU? I mean, how does
it look like under TOS _and_ after loading MiNT (earlier than 1.15.1 beta
0.6, because that last already contains the FPU detection routines). I
have no MSTE machine, so I cannot test it myself.

Thanks, 

--
Konrad M.Kokoszkiewicz
|mail: draco@mi.com.pl                  | Atari Falcon030/TT030/65XE |
|http://www.obta.uw.edu.pl/~draco/
|http://draco.atari.org

** Ea natura multitudinis est,
** aut servit humiliter, aut superbe dominatur (Liv. XXIV,25)
*************************************************************
** U pospolstwa normalne jest, ze albo sluzy ono unizenie,
** albo bezczelnie sie panoszy.