diff --git a/cpu/mips/Makefile b/cpu/mips/Makefile
index 92dcc16..5091781 100644
--- a/cpu/mips/Makefile
+++ b/cpu/mips/Makefile
@@ -25,13 +25,16 @@
 
 LIB	= $(obj)lib$(CPU).a
 
-START	= start.o
-COBJS	= asc_serial.o au1x00_serial.o au1x00_eth.o au1x00_usb_ohci.o \
-	  cpu.o interrupts.o incaip_clock.o
-SOBJS	= incaip_wdt.o cache.o
+SOBJS-y	= cache.o
+COBJS-y	= cpu.o interrupts.o
 
-SRCS	:= $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(SOBJS) $(COBJS))
+SOBJS-$(CONFIG_INCA_IP)	+= incaip_wdt.o
+COBJS-$(CONFIG_INCA_IP)	+= asc_serial.o incaip_clock.o
+COBJS-$(CONFIG_PURPLE)	+= asc_serial.o
+COBJS-$(CONFIG_SOC_AU1X00) += au1x00_eth.o au1x00_serial.o au1x00_usb_ohci.o
+
+SRCS	:= $(START:.o=.S) $(SOBJS-y:.o=.S) $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(SOBJS-y) $(COBJS-y))
 START	:= $(addprefix $(obj),$(START))
 
 all:	$(obj).depend $(START) $(LIB)
diff --git a/cpu/mips/asc_serial.c b/cpu/mips/asc_serial.c
index 3498b61..be686c2 100644
--- a/cpu/mips/asc_serial.c
+++ b/cpu/mips/asc_serial.c
@@ -4,8 +4,6 @@
 
 #include <config.h>
 
-#if defined(CONFIG_PURPLE) || defined(CONFIG_INCA_IP)
-
 #ifdef CONFIG_PURPLE
 #define	serial_init	asc_serial_init
 #define	serial_putc	asc_serial_putc
@@ -368,4 +366,3 @@
 
     return res;
 }
-#endif /* CONFIG_PURPLE || CONFIG_INCA_IP */
diff --git a/cpu/mips/au1x00_eth.c b/cpu/mips/au1x00_eth.c
index aeb9662..d0cf8e0 100644
--- a/cpu/mips/au1x00_eth.c
+++ b/cpu/mips/au1x00_eth.c
@@ -23,8 +23,6 @@
  */
 #include <config.h>
 
-#ifdef CONFIG_SOC_AU1X00
-
 #if defined(CFG_DISCOVER_PHY)
 #error "PHY not supported yet"
 /* We just assume that we are running 100FD for now */
@@ -307,5 +305,3 @@
 
 	return 1;
 }
-
-#endif /* CONFIG_SOC_AU1X00 */
diff --git a/cpu/mips/au1x00_serial.c b/cpu/mips/au1x00_serial.c
index ec10ac0..6309794 100644
--- a/cpu/mips/au1x00_serial.c
+++ b/cpu/mips/au1x00_serial.c
@@ -26,9 +26,6 @@
  */
 
 #include <config.h>
-
-#ifdef CONFIG_SOC_AU1X00
-
 #include <common.h>
 #include <asm/au1x00.h>
 
@@ -132,4 +129,3 @@
 	}
 	return 0;
 }
-#endif /* CONFIG_SOC_AU1X00 */
diff --git a/cpu/mips/au1x00_usb_ohci.c b/cpu/mips/au1x00_usb_ohci.c
index e03b125..1ca8aaf 100644
--- a/cpu/mips/au1x00_usb_ohci.c
+++ b/cpu/mips/au1x00_usb_ohci.c
@@ -35,7 +35,7 @@
 
 #include <config.h>
 
-#if defined(CONFIG_SOC_AU1X00) && defined(CONFIG_USB_OHCI)
+#ifdef CONFIG_USB_OHCI
 
 /* #include <pci.h> no PCI on the AU1x00 */