diff --git a/configs/C29XPCIE_NOR_SECBOOT_defconfig b/configs/C29XPCIE_NOR_SECBOOT_defconfig
index 6ad8a89..58e618b 100644
--- a/configs/C29XPCIE_NOR_SECBOOT_defconfig
+++ b/configs/C29XPCIE_NOR_SECBOOT_defconfig
@@ -27,4 +27,5 @@
 CONFIG_FSL_ESPI=y
 CONFIG_RSA=y
 CONFIG_SPL_RSA=y
+CONFIG_RSA_SOFTWARE_EXP=y
 CONFIG_OF_LIBFDT=y