diff --git a/meta-digi-dey/classes/trustfence.bbclass b/meta-digi-dey/classes/trustfence.bbclass
index b1a06c9ec..6eda06492 100644
--- a/meta-digi-dey/classes/trustfence.bbclass
+++ b/meta-digi-dey/classes/trustfence.bbclass
@@ -26,6 +26,7 @@ TRUSTFENCE_DEK_PATH:ccmp1 ?= "0"
 TRUSTFENCE_ENCRYPT_ENVIRONMENT ?= "1"
 TRUSTFENCE_ENCRYPT_ENVIRONMENT:ccmp1 ?= "0"
 TRUSTFENCE_SRK_REVOKE_MASK ?= "0x0"
+TRUSTFENCE_KEY_INDEX ?= "0"
 
 # Partition encryption configuration
 TRUSTFENCE_ENCRYPT_PARTITIONS ?= "1"