Index: head/sys/dev/sfxge/common/ef10_nic.c
===================================================================
--- head/sys/dev/sfxge/common/ef10_nic.c
+++ head/sys/dev/sfxge/common/ef10_nic.c
@@ -961,6 +961,50 @@
 	return (efx_mcdi_unlink_piobuf(enp, vi_index));
 }
 
+static	__checkReturn	efx_rc_t
+ef10_mcdi_get_pf_count(
+	__in		efx_nic_t *enp,
+	__out		uint32_t *pf_countp)
+{
+	efx_mcdi_req_t req;
+	uint8_t payload[MAX(MC_CMD_GET_PF_COUNT_IN_LEN,
+			    MC_CMD_GET_PF_COUNT_OUT_LEN)];
+	efx_rc_t rc;
+
+	(void) memset(payload, 0, sizeof (payload));
+	req.emr_cmd = MC_CMD_GET_PF_COUNT;
+	req.emr_in_buf = payload;
+	req.emr_in_length = MC_CMD_GET_PF_COUNT_IN_LEN;
+	req.emr_out_buf = payload;
+	req.emr_out_length = MC_CMD_GET_PF_COUNT_OUT_LEN;
+
+	efx_mcdi_execute(enp, &req);
+
+	if (req.emr_rc != 0) {
+		rc = req.emr_rc;
+		goto fail1;
+	}
+
+	if (req.emr_out_length_used < MC_CMD_GET_PF_COUNT_OUT_LEN) {
+		rc = EMSGSIZE;
+		goto fail2;
+	}
+
+	*pf_countp = *MCDI_OUT(req, uint8_t,
+				MC_CMD_GET_PF_COUNT_OUT_PF_COUNT_OFST);
+
+	EFSYS_ASSERT(*pf_countp != 0);
+
+	return (0);
+
+fail2:
+	EFSYS_PROBE(fail2);
+fail1:
+	EFSYS_PROBE1(fail1, efx_rc_t, rc);
+
+	return (rc);
+}
+
 	__checkReturn	efx_rc_t
 ef10_get_datapath_caps(
 	__in		efx_nic_t *enp)
@@ -975,6 +1019,9 @@
 					    &tso2nc)) != 0)
 		goto fail1;
 
+	if ((rc = ef10_mcdi_get_pf_count(enp, &encp->enc_hw_pf_count)) != 0)
+		goto fail1;
+
 #define	CAP_FLAG(flags1, field)		\
 	((flags1) & (1 << (MC_CMD_GET_CAPABILITIES_V2_OUT_ ## field ## _LBN)))
 
Index: head/sys/dev/sfxge/common/efx.h
===================================================================
--- head/sys/dev/sfxge/common/efx.h
+++ head/sys/dev/sfxge/common/efx.h
@@ -1142,6 +1142,8 @@
 	/* Number of TSO contexts on the NIC (FATSOv2) */
 	uint32_t		enc_fw_assisted_tso_v2_n_contexts;
 	boolean_t		enc_hw_tx_insert_vlan_enabled;
+	/* Number of PFs on the NIC */
+	uint32_t		enc_hw_pf_count;
 	/* Datapath firmware vadapter/vport/vswitch support */
 	boolean_t		enc_datapath_cap_evb;
 	boolean_t		enc_rx_disable_scatter_supported;
Index: head/sys/dev/sfxge/common/siena_nic.c
===================================================================
--- head/sys/dev/sfxge/common/siena_nic.c
+++ head/sys/dev/sfxge/common/siena_nic.c
@@ -105,6 +105,13 @@
 
 	encp->enc_board_type = board_type;
 
+	/*
+	 * There is no possibility to determine the number of PFs on Siena
+	 * by issuing MCDI request, and it is not an easy task to find the
+	 * value based on the board type, so 'enc_hw_pf_count' is set to 1
+	 */
+	encp->enc_hw_pf_count = 1;
+
 	/* Additional capabilities */
 	encp->enc_clk_mult = 1;
 	if (EFX_DWORD_FIELD(capabilities, MC_CMD_CAPABILITIES_TURBO)) {