Propose downloading proprietary blobs

Issue: FP3-A11#331
Change-Id: I7f2a65793689128fcb301f6b2a263d988a331854
(cherry picked from commit 50d6ff967669e792faf726113ba6d40c73b85e1b)
diff --git a/device.mk b/device.mk
index 61a9fd6..2c7bd24 100644
--- a/device.mk
+++ b/device.mk
@@ -989,11 +989,24 @@
 $(warning Using default blobs path: $(FP3_PROPRIETARY_PATH).)
 endif
 
+DEVICE_BLOB_VERSION := 4.A.0013.3
+
+GET_BLOBS_CMD = vendor/fairphone/tools/bin/get_blobs.py --device FP3 --build-id $(DEVICE_BLOB_VERSION) --blobs-dir $(FP3_PROPRIETARY_PATH)
+
+# Check the presence of proprietary blobs
+ifeq ("$(wildcard $(FP3_PROPRIETARY_PATH)/device-vendor.mk)","")
+define BLOBS_INSTRUCTION
+Cannot find FP3 binary blobs.
+Please run
+  $(GET_BLOBS_CMD)
+and accept the terms of agreement.
+endef
+$(error $(BLOBS_INSTRUCTION))
+endif
+
 # Call this in the end so that flags if required can be utilized.
 $(call inherit-product, $(FP3_PROPRIETARY_PATH)/device-vendor.mk)
 
-DEVICE_BLOB_VERSION := 4.A.0013.3
-
 # Build some more display components to vendor
 $(call inherit-product, vendor/qcom/opensource/commonsys-intf/display/config/display-interfaces-product.mk)
 ###################################################################################