diff --git a/tools/firmware/Makefile b/tools/firmware/Makefile
index 85902319e8..63ccb7b17e 100644
--- a/tools/firmware/Makefile
+++ b/tools/firmware/Makefile
@@ -30,7 +30,7 @@ all:
 .PHONY: install
 install: all
 	[ -d $(INSTALL_DIR) ] || install -d -m0755 $(INSTALL_DIR)
-	install -m0644 $(TARGET) $(INSTALL_DIR)
+	[ ! -e $(TARGET) ] || install -m0644 $(TARGET) $(INSTALL_DIR)
 
 .PHONY: clean
 clean: