Index: head/sys/arm/arm/machdep.c
===================================================================
--- head/sys/arm/arm/machdep.c
+++ head/sys/arm/arm/machdep.c
@@ -1111,6 +1111,8 @@
 	char *env;
 	void *kmdp;
 	int err_devmap, mem_regions_sz;
+	phandle_t root;
+	char dts_version[255];
 #ifdef EFI
 	struct efi_map_header *efihdr;
 #endif
@@ -1272,6 +1274,18 @@
 		    err_devmap);
 
 	platform_late_init();
+
+	root = OF_finddevice("/");
+	if (OF_getprop(root, "freebsd,dts-version", dts_version, sizeof(dts_version)) > 0) {
+		if (strcmp(LINUX_DTS_VERSION, dts_version) != 0)
+			printf("WARNING: DTB version is %s while kernel expects %s, "
+			    "please update the DTB in the ESP\n",
+			    dts_version,
+			    LINUX_DTS_VERSION);
+	} else {
+		printf("WARNING: Cannot find freebsd,dts-version property, "
+		    "cannot check DTB compliance\n");
+	}
 
 	/*
 	 * We must now clean the cache again....