On Tue, 3 Sep 2002, Frederick Bruckman wrote:
> What happens if you build a kernel without FPSP (with or without FPU)?

If I'm not mistaken, options FPSP only matters if you're running on a
68[LC]040... sys/arch/mac68k/mac68k/locore.s does a
  cmpl    #FPU_68040,_C_LABEL(fputype) | 68040 FPU?
and only calls the FPSP routines if the comparison is true. So a kernel
without FPSP shouldn't be any different on an '030 machine.

I do wonder about this bit of code around line 581 of locore.s though:

ENTRY_NOPROFILE(fpunsupp)
#if defined(M68040)
        cmpl    #FPU_68040,_C_LABEL(fputype) | 68040 FPU?
        jne     _C_LABEL(illinst)       | no, treat as illinst
#ifdef FPSP
        jmp     _ASM_LABEL(fpsp_unsupp) | yes, go handle it
#endif
Lfp_unsupp:
#endif /* M68040 */
#ifdef FPU_EMULATE
        clrl    %sp@-                   | stack adjust count
        moveml  #0xFFFF,%sp@-           | save registers
        moveq   #T_FPEMULD,%d0          | denote as FP emulation trap
        jra     _ASM_LABEL(fault)       | do it
#else
        jra     _C_LABEL(illinst)
#endif

Shouldn't that jne _C_LABEL(illinst)       | no, treat as illinst
be a jne _C_LABEL(Lfp_unsupp)?

CVS says:

revision 1.80
date: 1997/06/29 06:07:39;  author: scottr;  state: Exp;  lines: +590 -745
Get several cleanup chores out of the way.  The code is functionally
identical to the previous incarnation.

However, a diff between 1.79 and 1.80 shows:
-       cmpl    #FPU_68040,_fputype     | 68040? (see fpu.c)
-       jne     Lfp_unsupp              | no, treat as illinst
+       cmpl    #FPU_68040,_C_LABEL(fputype) | 68040 FPU?
+       jne     _C_LABEL(illinst)       | no, treat as illinst

which doesn't look like a functionally identical change to me :)
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