diff --git a/util/inteltool/Makefile b/util/inteltool/Makefile
index b51f5a2ad8..e36560d6e1 100644
--- a/util/inteltool/Makefile
+++ b/util/inteltool/Makefile
@@ -22,9 +22,11 @@ top ?= $(abspath ../..)
 CC      ?= gcc
 INSTALL ?= /usr/bin/install
 PREFIX  ?= /usr/local
-CFLAGS  ?= -O2 -g -Wall -W -I$(top)/src/commonlib/include
+CFLAGS  ?= -O2 -g -Wall -W
 LDFLAGS += -lpci -lz
 
+CPPFLAGS += -I$(top)/src/commonlib/include
+
 OBJS = inteltool.o cpu.o gpio.o rootcmplx.o powermgt.o memory.o pcie.o amb.o ivy_memory.o spi.o gfx.o ahci.o
 
 OS_ARCH	= $(shell uname)
@@ -32,19 +34,19 @@ ifeq ($(OS_ARCH), Darwin)
 LDFLAGS += -framework DirectHW
 endif
 ifeq ($(OS_ARCH), FreeBSD)
-CFLAGS += -I/usr/local/include
+CPPFLAGS += -I/usr/local/include
 LDFLAGS += -L/usr/local/lib
 LIBS = -lz
 endif
 ifeq ($(OS_ARCH), NetBSD)
-CFLAGS += -I/usr/pkg/include
+CPPFLAGS += -I/usr/pkg/include
 LDFLAGS += -L/usr/pkg/lib -Wl,-rpath-link,/usr/pkg/lib -lz -lpciutils -lpci -l$(shell uname -p)
 endif
 
 all: pciutils dep $(PROGRAM)
 
 $(PROGRAM): $(OBJS)
-	$(CC) $(CFLAGS) -o $(PROGRAM) $(OBJS) $(LDFLAGS)
+	$(CC) $(CFLAGS) $(CPPFLAGS) -o $(PROGRAM) $(OBJS) $(LDFLAGS)
 
 clean:
 	rm -f $(PROGRAM) *.o *~ junit.xml
@@ -53,7 +55,7 @@ distclean: clean
 	rm -f .dependencies
 
 dep:
-	@$(CC) $(CFLAGS) -MM *.c > .dependencies
+	@$(CC) $(CFLAGS) $(CPPFLAGS) -MM *.c > .dependencies
 
 define LIBPCI_TEST
 /* Avoid a failing test due to libpci header symbol shadowing breakage */
@@ -77,8 +79,9 @@ export LIBPCI_TEST
 pciutils:
 	@printf "\nChecking for pciutils and zlib... "
 	@echo "$$LIBPCI_TEST" > .test.c
-	@$(CC) $(CFLAGS) .test.c -o .test $(LDFLAGS) >/dev/null 2>&1 &&	  \
-		printf "found.\n" || ( printf "not found.\n\n"; 	  \
+	@$(CC) $(CFLAGS) $(CPPFLAGS) .test.c -o .test $(LDFLAGS)	  \
+						>/dev/null 2>&1 &&	  \
+		printf "found.\n" || ( printf "not found.\n\n";		  \
 		printf "Please install pciutils-devel and zlib-devel.\n"; \
 		printf "See README for more information.\n\n";		  \
 		rm -f .test.c .test; exit 1)