diff --git a/arch/powerpc/cpu/mpc85xx/config.mk b/arch/powerpc/cpu/mpc85xx/config.mk
index f36d823..d1765cd 100644
--- a/arch/powerpc/cpu/mpc85xx/config.mk
+++ b/arch/powerpc/cpu/mpc85xx/config.mk
@@ -23,7 +23,7 @@
 
 PLATFORM_RELFLAGS += -meabi
 
-PLATFORM_CPPFLAGS += -ffixed-r2 -Wa,-me500 -msoft-float -mno-string
+PLATFORM_CPPFLAGS += -ffixed-r2 -mcpu=8540 -Wa,-me500 -msoft-float -mno-string
 
 # -mspe=yes is needed to have -mno-spe accepted by a buggy GCC;
 # see "[PATCH,rs6000] make -mno-spe work as expected" on
