diff --git a/drivers/firmware/scmi/Makefile b/drivers/firmware/scmi/Makefile
index 336ea1f..d22f53e 100644
--- a/drivers/firmware/scmi/Makefile
+++ b/drivers/firmware/scmi/Makefile
@@ -1,2 +1,4 @@
 obj-y	+= scmi_agent-uclass.o
+obj-y	+= smt.o
+obj-$(CONFIG_DM_MAILBOX)	+= mailbox_agent.o
 obj-$(CONFIG_SANDBOX)		+= sandbox-scmi_agent.o