diff --git a/pc-bios/s390-ccw/Makefile b/pc-bios/s390-ccw/Makefile
index 15e423274f..11c5dd4799 100644
--- a/pc-bios/s390-ccw/Makefile
+++ b/pc-bios/s390-ccw/Makefile
@@ -10,7 +10,7 @@ $(call set-vpath, $(SRC_PATH)/pc-bios/s390-ccw)
 .PHONY : all clean build-all
 
 OBJECTS = start.o main.o bootmap.o sclp-ascii.o virtio.o
-CFLAGS += -fPIE -fno-stack-protector -ffreestanding
+CFLAGS += -fPIE -fno-stack-protector -ffreestanding -march=z900
 CFLAGS += -fno-delete-null-pointer-checks -msoft-float
 LDFLAGS += -Wl,-pie -nostdlib