RE: PATCH: (on Alpha) emulating missing instructions

Richard B. Johnson (root@chaos.analogic.com)
Fri, 15 Oct 1999 09:36:00 -0400 (EDT)


On Fri, 15 Oct 1999, Jones D (ISaCS) wrote:

>
> > > We already have FPU emulation in kernel, and there
> > That should probably have been in userspace.
>
> That could be a worthwhile project at some point, as
> that's a fair amount of code. The only thing that concerns
> me, is that is the FP emulation code there to allow booting
> on 386s with no FPU ?
>
> Ie, without it, will the kernel boot on a PC without an FPU ?
>
> regards,
>
> Dave.
>

There should be no FPU requirements in the kernel. The fact that
the kernel will not continue booting if a FPU is not found, but
FPU emulation has not been compiled in, is an artificial constraint
imposed by the initialization code.

The purpose of the FPU emulation is not to allow the machine to boot.
Instead, it is to allow floating-point instructions to be emulated. This
allows programs that use floating point operations to run without having
to be especially compiled against a 'C' floating-point emulator library
like M$DOS 'C' compilers.

Cheers,
Dick Johnson
**** FILE SYSTEM WAS MODIFIED ****
Penguin : Linux version 2.3.13 on an i686 machine (400.59 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/