m68k: handle presence of 64bit mul/div instructions cleanly

The traditional 68000 processors and the newer reduced instruction set
ColdFire processors do not support the 32*32->64 multiply or the 64/32->32
divide instructions. This is not a difference based on the presence of
a hardware MMU or not.

Create a new config symbol to mark that a CPU type doesn't support the
longer multiply/divide instructions. Use this then as a basis for using
the fast 64bit based divide (in div64.h) and for linking in the extra
libgcc functions that may be required (mulsi3, divsi3, etc).

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 2fe2d633fe08..32fd3642e71b 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -63,6 +63,9 @@ config ZONE_DMA
 config CPU_HAS_NO_BITFIELDS
         bool
 
+config CPU_HAS_NO_MULDIV64
+        bool
+
 config HZ
         int
         default 1000 if CLEOPATRA