--- Rules.mak
+++ Rules.mak
@@ -162,6 +162,9 @@
 endif
 
 ifeq ($(strip $(TARGET_ARCH)),mips)
+ifneq ($(strip $(MIPS_CUSTOM_ARCH_CPU_CFLAGS)),)
+	CPU_CFLAGS-y+=$(strip $(MIPS_CUSTOM_ARCH_CPU_CFLAGS))
+else
 	CPU_CFLAGS-$(CONFIG_MIPS_ISA_1)+=-mips1
 	CPU_CFLAGS-$(CONFIG_MIPS_ISA_2)+=-mips2 -mtune=mips2
 	CPU_CFLAGS-$(CONFIG_MIPS_ISA_3)+=-mips3 -mtune=mips3
@@ -169,6 +172,7 @@
 	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS32)+=-mips32 -mtune=mips32
 	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS64)+=-mips64 -mtune=mips32
 endif
+endif
 
 ifeq ($(strip $(TARGET_ARCH)),sh)
 	OPTIMIZATION+=-fstrict-aliasing