diff --git a/plat/xilinx/zynqmp/include/plat_ipi.h b/plat/xilinx/zynqmp/include/plat_ipi.h
index bccd2f1..a78f93a 100644
--- a/plat/xilinx/zynqmp/include/plat_ipi.h
+++ b/plat/xilinx/zynqmp/include/plat_ipi.h
@@ -41,7 +41,7 @@
 #define IPI_BUFFER_TARGET_LOCAL_OFFSET	0x80U
 #define IPI_BUFFER_TARGET_REMOTE_OFFSET	0x1C0U
 
-#define IPI_BUFFER_MAX_WORDS	8
+#define IPI_BUFFER_MAX_WORDS	8U
 
 #define IPI_BUFFER_REQ_OFFSET	0x0U
 #define IPI_BUFFER_RESP_OFFSET	0x20U