diff --git a/rpi-update b/rpi-update
index 1d82db4..f9df64d 100755
--- a/rpi-update
+++ b/rpi-update
@@ -26,7 +26,11 @@ fi
 
 BRANCH=${BRANCH:-"master"}
 ROOT_PATH=${ROOT_PATH:-"/"}
-CUR_FW_SUBDIR="/$(echo =$(vcgencmd get_config os_prefix) | cut -d'=' -f3)"
+if command -v vcgencmd > /dev/null; then
+	CUR_FW_SUBDIR="/$(echo =$(vcgencmd get_config os_prefix) | cut -d'=' -f3)"
+else
+	CUR_FW_SUBDIR="/"
+fi
 FW_SUBDIR=${FW_SUBDIR:-${CUR_FW_SUBDIR}}
 if [[ "${FW_SUBDIR}" != "" ]]; then
 	if [[ "${FW_SUBDIR::1}" != "/" ]]; then