diff --git a/documentation/ref-manual/ref-variables.xml b/documentation/ref-manual/ref-variables.xml
index 0eb5d98c58..a07cada8e8 100644
--- a/documentation/ref-manual/ref-variables.xml
+++ b/documentation/ref-manual/ref-variables.xml
@@ -3257,6 +3257,24 @@
+ IMAGE_BOOT_FILES
+
+
+ Comma separated list of files that will be installed into
+ boot partition when preparing an image. Source files By default the file
+ is installed under the same name as source file. To change
+ the destination name, separate it with ";". Source files
+ need to be located in
+ DEPLOY_DIR_IMAGE.
+ Examples:
+
+
+ IMAGE_BOOT_FILES = "u-boot.img uImage:kernel"
+ IMAGE_BOOT_FILES = "u-boot.${UBOOT_SUFFIX} ${KERNEL_IMAGETYPE}""
+
+
+
+
IMAGE_CLASSES