diff --git a/rules/pulpos/targets/pulp_cluster.mk b/rules/pulpos/targets/pulp_cluster.mk
index 033b2c6..2c34d1e 100644
--- a/rules/pulpos/targets/pulp_cluster.mk
+++ b/rules/pulpos/targets/pulp_cluster.mk
@@ -54,6 +54,9 @@ PULP_SRCS     += kernel/fll-v$(fll/version).c
 PULP_SRCS     += kernel/freq-domains.c
 PULP_SRCS     += kernel/chips/pulp_cluster/soc.c
 
+# HMR
+PULP_CFLAGS += -DARCHI_HMR
+PULP_SRCS += kernel/hmr_synch.c
 
 include $(PULPRT_HOME)/rules/pulpos/configs/default.mk