diff --git a/target/linux/mpc52xx/Makefile b/target/linux/mpc52xx/Makefile
index 152e51e58341f093d300eac54f903923d30ee0ae..b4649e45c4b2fee3c4b2d5e6cd529f00c897d2f2 100644
--- a/target/linux/mpc52xx/Makefile
+++ b/target/linux/mpc52xx/Makefile
@@ -9,6 +9,7 @@ include $(TOPDIR)/rules.mk
 ARCH:=powerpc
 BOARD:=mpc52xx
 BOARDNAME:=Freescale MPC52xx
+CFLAGS:=-Os -pipe -funit-at-a-time -mcpu=603e
 FEATURES:=targz ext4
 
 LINUX_VERSION:=2.6.30.10
diff --git a/target/linux/mpc83xx/Makefile b/target/linux/mpc83xx/Makefile
index f13a961ca5dbf1577d43e96e34afcdc0a1a72318..40ed374fa9445af6ff4d2d07ad456fcf5c6334b2 100644
--- a/target/linux/mpc83xx/Makefile
+++ b/target/linux/mpc83xx/Makefile
@@ -9,6 +9,7 @@ include $(TOPDIR)/rules.mk
 ARCH:=powerpc
 BOARD:=mpc83xx
 BOARDNAME:=Freescale MPC83xx
+CFLAGS:=-Os -pipe -funit-at-a-time -mcpu=603e
 FEATURES:=squashfs targz broken
 MAINTAINER:=Imre Kaloz <kaloz@openwrt.org>