Re: 2.4.0-test9 + Winchip2/2A processor family == hang on boot

From: Mikael Pettersson (mikpe@csd.uu.se)
Date: Wed Oct 11 2000 - 04:48:23 EST


On Wed, 11 Oct 2000, Frank de Lange wrote:

>Solved the problem with Winchip not booting. It turns out they do not like the
>code generated by gcc (gcc version 2.95.2 19991024 (release)) when the
>-march=i686 flag is set. Changing this flag to -march=i586 makes to box boot
>like it should.

That makes sense. The WinChip C6/2/3 processors were designed to
be compatible with the Intel Pentium and Pentium MMX processors.
They are _not_ compatible with P6 cores at the application level;
in particular, they do not have the conditional move instructions.

"-march=i686" permits gcc to use i686-specific instructions. Seriously
uncool if the processor doesn't have them.

I don't know if WinChips benefit from i686-like scheduling heuristics,
but perhaps "-mcpu=i686" would be appropriate for the Makefile
(i.e. use the i386 instruction set but schedule etc. as for an i686).

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



This archive was generated by hypermail 2b29 : Sun Oct 15 2000 - 21:00:17 EST