diff --git a/board/mpc8641hpcn/Makefile b/board/mpc8641hpcn/Makefile
index f70f44b..46214ed 100644
--- a/board/mpc8641hpcn/Makefile
+++ b/board/mpc8641hpcn/Makefile
@@ -23,12 +23,16 @@
 
 include $(TOPDIR)/config.mk
 
-LIB	= lib$(BOARD).a
+LIB	= $(obj)lib$(BOARD).a
 
-OBJS	:= $(BOARD).o pixis.o sys_eeprom.o
+COBJS	:= $(BOARD).o pixis.o sys_eeprom.o
 SOBJS	:= init.o
 
-$(LIB):	$(OBJS) $(SOBJS)
+SRCS	:= $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+SOBJS	:= $(addprefix $(obj),$(SOBJS))
+
+$(LIB):	$(obj).depend $(OBJS) $(SOBJS)
 	$(AR) crv $@ $(OBJS)
 
 clean:
@@ -40,10 +44,9 @@
 
 #########################################################################
 
-.depend:	Makefile $(SOBJS:.o=.S) $(OBJS:.o=.c)
-		$(CC) -M $(CPPFLAGS) $(SOBJS:.o=.S) $(OBJS:.o=.c) > $@
-ifeq ($(filter distclean, $(MAKECMDGOALS)),)
--include .depend
-endif
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude ($obj).depend
 
 #########################################################################
diff --git a/cpu/mpc86xx/Makefile b/cpu/mpc86xx/Makefile
index 7995945..ad5b36d 100644
--- a/cpu/mpc86xx/Makefile
+++ b/cpu/mpc86xx/Makefile
@@ -25,24 +25,27 @@
 
 include $(TOPDIR)/config.mk
 
-LIB	= lib$(CPU).a
+LIB	= $(obj)lib$(CPU).a
 
 START	= start.o #resetvec.o
-ASOBJS  = cache.o
+SOBJS	= cache.o
 COBJS	= traps.o cpu.o cpu_init.o speed.o interrupts.o \
 	  pci.o pcie_indirect.o i2c.o spd_sdram.o
-OBJS	= $(COBJS)
 
-all:	.depend $(START) $(ASOBJS) $(LIB)
+SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
+START	:= $(addprefix $(obj),$(START))
+
+all:	$(obj).depend $(START) $(LIB)
 
 $(LIB):	$(OBJS)
 	$(AR) crv $@ $(ASOBJS) $(OBJS)
 
 #########################################################################
 
-.depend:	Makefile $(START:.o=.S) $(ASOBJS:.o=.S) $(COBJS:.o=.c)
-		$(CC) -M $(CFLAGS) $(START:.o=.S) $(ASOBJS:.o=.S) $(COBJS:.o=.c) > $@
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
 
-sinclude .depend
+sinclude $(obj).depend
 
 #########################################################################