--- linux-2.6.13/include/asm-mips/unistd.h
+++ linux-2.6.13/include/asm-mips/unistd.h
@@ -13,6 +13,7 @@
 #define _ASM_UNISTD_H
 
 #include <asm/sgidefs.h>
+#include <linux/config.h>
 
 #if _MIPS_SIM == _MIPS_SIM_ABI32