diff --git a/boot/uboot/Config.in b/boot/uboot/Config.in
index f5c20f5168..085397d03d 100644
--- a/boot/uboot/Config.in
+++ b/boot/uboot/Config.in
@@ -492,6 +492,8 @@ config BR2_TARGET_UBOOT_ZYNQMP_PMUFW
 	  (e.g. http://...), and it will be downloaded and used from
 	  the download directory.
 
+	  The PMU firmware binary can be either in ELF or BIN format.
+
 	  If empty, the generated boot.bin will not contain a PMU
 	  firmware.