upgrade: Honnor the PROBE_HOST make argument.

upgrade/Makefile

@@ -1,5 +1,13 @@
 OUTFILE = blackmagic_upgrade
 
+PC_HOSTED =
+ifeq ($(PROBE_HOST), libftdi)
+        PC_HOSTED = true
+endif
+ifeq ($(PROBE_HOST), pc-stlinkv2)
+        PC_HOSTED = true
+endif
+
 CC = $(CROSS_COMPILE)gcc
 
 CFLAGS = -Wall -Wextra -std=gnu99 -O0 -g -MD -mno-ms-bitfields
@@ -10,9 +18,29 @@ OBJ =	bindata.o	\
 	stm32mem.o	\
 	main.o
 
-all: $(OUTFILE)
+ifndef $(PROBE_HOST)
+	PROBE_HOST=native
+endif
 
-bindata.o: ../src/blackmagic.bin
+ifndef  PC_HOSTED
+all: $(OUTFILE)
+else
+all:
+ ifeq ($(PROBE_HOST), libftdi)
+	@echo "Libftdi needs no firmware update"
+ endif
+ ifeq ($(PROBE_HOST), pc-stlinkv2)
+	@echo "Pc-stlinkv2 use ST provided tools for firmware update"
+ endif
+endif
+
+bindata.o: $(PROBE_HOST).d
+
+$(PROBE_HOST).d: ../src/blackmagic.bin
+	-rm *.d
+	make -C ../src $0 clean
+	make -C ../src $0
+	touch $(PROBE_HOST).d
 
 $(OUTFILE) $(OUTFILE).exe: $(OBJ)
 	$(CC) $(CFLAGS) -o $@ $^ $(LDFLAGS)