diff --git a/Makefile.include b/Makefile.include
index 4decf6ed66282922a639b3027c56fc8fa5d457aa..2955ef44f66daab3c03cf9304aea817ee6115b94 100644
--- a/Makefile.include
+++ b/Makefile.include
@@ -159,6 +159,10 @@ endif
 
 export TOOLCHAIN
 
+# default toolchain prefix, defaults to target triple followed by a dash, you
+# will most likely not need to touch this.
+export PREFIX ?= $(if $(TARGET_ARCH),$(TARGET_ARCH)-)
+
 # Import all toolchain settings
 include $(RIOTCPU)/Makefile.include.$(TOOLCHAIN)
 
diff --git a/cpu/Makefile.include.cortexm_common b/cpu/Makefile.include.cortexm_common
index 6537e465ca2d9a9db14f745af21df7ccea56ac4d..4eac2434931d34a344172b2e785d7b9d266c1542 100644
--- a/cpu/Makefile.include.cortexm_common
+++ b/cpu/Makefile.include.cortexm_common
@@ -1,10 +1,6 @@
 # Target triple for the build. Use arm-none-eabi if you are unsure.
 export TARGET_ARCH ?= arm-none-eabi
 
-# default toolchain prefix, defaults to target triple followed by a dash, you
-# will most likely not need to touch this.
-export PREFIX ?= $(if $(TARGET_ARCH),$(TARGET_ARCH)-)
-
 # define build specific options
 export CFLAGS_CPU   = -mcpu=$(MCPU) -mlittle-endian -mthumb $(CFLAGS_FPU)
 ifneq (llvm,$(TOOLCHAIN))