cxgb4: when max_tx_rate is 0 disable tx rate limiting

in ndo_set_vf_rate() when max_tx_rate is 0 disable tx
rate limiting for that vf.
Signed-off-by: NCasey Leedom <leedom@chelsio.com>
Signed-off-by: NGanesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c

@@ -2749,6 +2749,27 @@ static int cxgb4_mgmt_set_vf_rate(struct net_device *dev, int vf,
 		return -EINVAL;
 	}
 
+	if (max_tx_rate == 0) {
+		/* unbind VF to to any Traffic Class */
+		fw_pfvf =
+		    (FW_PARAMS_MNEM_V(FW_PARAMS_MNEM_PFVF) |
+		     FW_PARAMS_PARAM_X_V(FW_PARAMS_PARAM_PFVF_SCHEDCLASS_ETH));
+		fw_class = 0xffffffff;
+		ret = t4_set_params(adap, adap->mbox, adap->pf, vf + 1, 1,
+				    &fw_pfvf, &fw_class);
+		if (ret) {
+			dev_err(adap->pdev_dev,
+				"Err %d in unbinding PF %d VF %d from TX Rate Limiting\n",
+				ret, adap->pf, vf);
+			return -EINVAL;
+		}
+		dev_info(adap->pdev_dev,
+			 "PF %d VF %d is unbound from TX Rate Limiting\n",
+			 adap->pf, vf);
+		adap->vfinfo[vf].tx_rate = 0;
+		return 0;
+	}
+
 	ret = t4_get_link_params(pi, &link_ok, &speed, &mtu);
 	if (ret != FW_SUCCESS) {
 		dev_err(adap->pdev_dev,
@@ -2798,8 +2819,8 @@ static int cxgb4_mgmt_set_vf_rate(struct net_device *dev, int vf,
 			    &fw_class);
 	if (ret) {
 		dev_err(adap->pdev_dev,
-			"Err %d in binding VF %d to Traffic Class %d\n",
-			ret, vf, class_id);
+			"Err %d in binding PF %d VF %d to Traffic Class %d\n",
+			ret, adap->pf, vf, class_id);
 		return -EINVAL;
 	}
 	dev_info(adap->pdev_dev, "PF %d VF %d is bound to Class %d\n",