diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index 2775bcafe40f..28752f6c96f0 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -333,6 +333,13 @@ scmi_perf_describe_levels_get(const struct scmi_protocol_handle *ph, u32 domain,
 	return ret;
 }
 
+static int scmi_perf_num_domains_get(const struct scmi_protocol_handle *ph)
+{
+	struct scmi_perf_info *pi = ph->get_priv(ph);
+
+	return pi->num_domains;
+}
+
 static int scmi_perf_mb_limits_set(const struct scmi_protocol_handle *ph,
 				   u32 domain, u32 max_perf, u32 min_perf)
 {
@@ -726,6 +733,7 @@ scmi_power_scale_get(const struct scmi_protocol_handle *ph)
 }
 
 static const struct scmi_perf_proto_ops perf_proto_ops = {
+	.num_domains_get = scmi_perf_num_domains_get,
 	.limits_set = scmi_perf_limits_set,
 	.limits_get = scmi_perf_limits_get,
 	.level_set = scmi_perf_level_set,
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index a21d111cfbd4..70ec6a77a9b5 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -104,6 +104,7 @@ struct scmi_clk_proto_ops {
  * struct scmi_perf_proto_ops - represents the various operations provided
  *	by SCMI Performance Protocol
  *
+ * @num_domains_get: gets the number of supported performance domains
  * @limits_set: sets limits on the performance level of a domain
  * @limits_get: gets limits on the performance level of a domain
  * @level_set: sets the performance level of a domain
@@ -123,6 +124,7 @@ struct scmi_clk_proto_ops {
  *	or in some other (abstract) scale
  */
 struct scmi_perf_proto_ops {
+	int (*num_domains_get)(const struct scmi_protocol_handle *ph);
 	int (*limits_set)(const struct scmi_protocol_handle *ph, u32 domain,
 			  u32 max_perf, u32 min_perf);
 	int (*limits_get)(const struct scmi_protocol_handle *ph, u32 domain,