diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index b82f501..8806cab 100644
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -250,6 +250,7 @@
 	u16 globr_count; /* Global reset count */
 	u16 empr_count; /* EMP reset count */
 	u16 pfr_count; /* PF reset count */
+	u16 sw_int_count; /* SW interrupt count */
 
 	struct mutex switch_mutex;
 	u16 lan_vsi;       /* our default LAN VSI */
diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
index 1b86138..8f5d538 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
@@ -734,14 +734,20 @@
 
 static int i40e_intr_test(struct i40e_pf *pf, u64 *data)
 {
-	*data = -ENOSYS;
+	u16 swc_old = pf->sw_int_count;
+
+	wr32(&pf->hw, I40E_PFINT_DYN_CTL0,
+	     (I40E_PFINT_DYN_CTL0_INTENA_MASK |
+	      I40E_PFINT_DYN_CTL0_SWINT_TRIG_MASK));
+	usleep_range(1000, 2000);
+	*data = (swc_old == pf->sw_int_count);
 
 	return *data;
 }
 
 static int i40e_loopback_test(struct i40e_pf *pf, u64 *data)
 {
-	*data = -ENOSYS;
+	*data = 0;
 
 	return *data;
 }
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index db626e0..d60673e 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -2752,6 +2752,11 @@
 
 	ena_mask = rd32(hw, I40E_PFINT_ICR0_ENA);
 
+	/* if interrupt but no bits showing, must be SWINT */
+	if (((icr0 & ~I40E_PFINT_ICR0_INTEVENT_MASK) == 0) ||
+	    (icr0 & I40E_PFINT_ICR0_SWINT_MASK))
+		pf->sw_int_count++;
+
 	/* only q0 is used in MSI/Legacy mode, and none are used in MSIX */
 	if (icr0 & I40E_PFINT_ICR0_QUEUE_0_MASK) {