ramips: add factory image for WNDR3700v5

This uses the existing rules for Sercomm factory images and moves them
to the ramips image Makefile, so they can be used in all subtargets.

The new factory image for WNDR3700v5 can be flashed using nmrpflash.

Signed-off-by: Jan Hoffmann <jan@3e8.eu>

target/linux/ramips/image/Makefile

@@ -10,6 +10,7 @@ include $(INCLUDE_DIR)/image.mk
 DEVICE_VARS += DTS IMAGE_SIZE NETGEAR_BOARD_ID NETGEAR_HW_ID
 DEVICE_VARS += BUFFALO_TAG_PLATFORM BUFFALO_TAG_VERSION BUFFALO_TAG_MINOR
 DEVICE_VARS += SEAMA_SIGNATURE SEAMA_MTDBLOCK
+DEVICE_VARS += SERCOMM_HWID SERCOMM_HWVER SERCOMM_SWVER
 
 loadaddr-y := 0x80000000
 loadaddr-$(CONFIG_TARGET_ramips_rt288x) := 0x88000000
@@ -132,6 +133,19 @@ define Build/zyimage
 	$(STAGING_DIR_HOST)/bin/zyimage $(1) $@
 endef
 
+define Build/sercom-seal
+	$(STAGING_DIR_HOST)/bin/mksercommfw \
+		-i $@ \
+		-b $(SERCOMM_HWID) \
+		-r $(SERCOMM_HWVER) \
+		-v $(SERCOMM_SWVER) \
+		$(1)
+endef
+
+define Build/sercom-footer
+	$(call Build/sercom-seal,-f)
+endef
+
 ralink_default_fw_size_4M=3866624
 ralink_default_fw_size_8M=8060928
 ralink_default_fw_size_16M=16121856

target/linux/ramips/image/mt7621.mk

@@ -531,7 +531,16 @@ TARGET_DEVICES += mqmaker_witi-512m
 
 define Device/wndr3700v5
   DTS := WNDR3700V5
-  IMAGE_SIZE := $(ralink_default_fw_size_16M)
+  BLOCKSIZE := 64k
+  IMAGE_SIZE := 15232k
+  SERCOMM_HWID := AYB
+  SERCOMM_HWVER := A001
+  SERCOMM_SWVER := 0x1054
+  IMAGES += factory.img
+  IMAGE/default := append-kernel | pad-to $$$$(BLOCKSIZE) | append-rootfs | pad-rootfs
+  IMAGE/sysupgrade.bin := $$(IMAGE/default) | append-metadata | check-size $$$$(IMAGE_SIZE)
+  IMAGE/factory.img := pad-extra 320k | $$(IMAGE/default) | pad-to $$$$(BLOCKSIZE) | \
+	sercom-footer | pad-to 128 | zip WNDR3700v5.bin | sercom-seal
   DEVICE_TITLE := Netgear WNDR3700v5
   DEVICE_PACKAGES := kmod-mt7603 kmod-mt76x2 kmod-usb3 wpad-basic
 endef

target/linux/ramips/image/mt76x8.mk

@@ -2,22 +2,6 @@
 # MT76x8 Profiles
 #
 
-DEVICE_VARS += SERCOMM_HWID SERCOMM_HWVER SERCOMM_SWVER
-
-define Build/sercom-seal
-	$(STAGING_DIR_HOST)/bin/mksercommfw \
-		-i $@ \
-		-b $(SERCOMM_HWID) \
-		-r $(SERCOMM_HWVER) \
-		-v $(SERCOMM_SWVER) \
-		$(1)
-endef
-
-define Build/sercom-footer
-	$(call Build/sercom-seal,-f)
-endef
-
-
 define Device/tplink
   TPLINK_FLASHLAYOUT :=
   TPLINK_HWID :=