diff --git a/target/linux/bcm53xx/image/Makefile b/target/linux/bcm53xx/image/Makefile
index 61bc39cfd6..2acf107b35 100644
--- a/target/linux/bcm53xx/image/Makefile
+++ b/target/linux/bcm53xx/image/Makefile
@@ -13,16 +13,7 @@ define Image/Prepare
 	$(call prepare_generic_squashfs,$(KDIR)/fs_mark)
 endef
 
-define Image/Build/Initramfs
-	$(call Image/Build/Initramfs/Chk,bcm4708-netgear-r6250,U12H245T00_NETGEAR,2,initramfs)
-endef
-
-define Image/Build/Initramfs/Chk
-	$(call Image/Build/Initramfs/DTB,$(1))
-	$(STAGING_DIR_HOST)/bin/mkchkimg -o $(BIN_DIR)/openwrt-$(1)-$(4).chk -k $(KDIR)/$(IMG_PREFIX)-$(4)-$(1).trx -b $(2) -r $(3)
-endef
-
-define Image/Build/Initramfs/DTB
+define Image/Build/initramfs/DTB
 	$(call Image/Build/DTB,zImage-initramfs,$(1))
 	$(STAGING_DIR_HOST)/bin/trx -o $(KDIR)/$(IMG_PREFIX)-initramfs-$(1).trx \
 		-f $(KDIR)/zImage-initramfs-$(1).lzma
@@ -35,11 +26,6 @@ define Image/Build/squashfs/DTB
 		-a 1024 -f $(KDIR)/root.squashfs -a 0x10000 -A $(KDIR)/fs_mark
 endef
 
-define Image/Build/squashfs/Chk
-	$(call Image/Build/squashfs/DTB,$(1))
-	$(STAGING_DIR_HOST)/bin/mkchkimg -o $(BIN_DIR)/openwrt-$(1)-$(4).chk -k $(KDIR)/$(IMG_PREFIX)-$(4)-$(1).trx -b $(2) -r $(3)
-endef
-
 define Image/Build/DTB
 	rm -f $(KDIR)/$(1)-$(2).lzma
 	rm -f $(KDIR)/$(1)-$(2).dts
@@ -47,10 +33,18 @@ define Image/Build/DTB
 	$(STAGING_DIR_HOST)/bin/lzma e $(KDIR)/$(1)-$(2).dts $(KDIR)/$(1)-$(2).lzma -d16
 endef
 
-define Image/Build
-	$(call Image/Build/$(1),$(1))
-	$(call Image/Build/squashfs/Chk,bcm4708-netgear-r6250,U12H245T00_NETGEAR,2,squashfs)
+define Image/Build/Chk
+	$(call Image/Build/$(1)/DTB,$(2))
+	$(STAGING_DIR_HOST)/bin/mkchkimg -o $(BIN_DIR)/openwrt-$(2)-$(1).chk -k $(KDIR)/$(IMG_PREFIX)-$(1)-$(2).trx -b $(3) -r $(4)
 endef
 
+# $(1): filesystem type (e.g. squashfs, initramfs).
+define Image/Build
+	$(call Image/Build/Chk,$(1),bcm4708-netgear-r6250,U12H245T00_NETGEAR,2)
+endef
+
+define Image/Build/Initramfs
+	$(call Image/Build,initramfs)
+endef
 
 $(eval $(call BuildImage))