nfp: move link state interrupt request/free calls

We need to be able to disable the link state interrupt when
the device is brought down.  We used to just free the IRQ
at the beginning of .ndo_stop().  As we now move towards
more ordered .ndo_open()/.ndo_stop() paths LSC allocation
should be placed in the "allocate resource" section.

Since the IRQ can't be freed early in .ndo_stop(), it is
disabled instead.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -1729,10 +1729,16 @@ static int nfp_net_netdev_open(struct net_device *netdev)
 				      NFP_NET_IRQ_EXN_IDX, nn->exn_handler);
 	if (err)
 		return err;
+	err = nfp_net_aux_irq_request(nn, NFP_NET_CFG_LSC, "%s-lsc",
+				      nn->lsc_name, sizeof(nn->lsc_name),
+				      NFP_NET_IRQ_LSC_IDX, nn->lsc_handler);
+	if (err)
+		goto err_free_exn;
+	disable_irq(nn->irq_entries[NFP_NET_CFG_LSC].vector);
 
 	err = nfp_net_alloc_rings(nn);
 	if (err)
-		goto err_free_exn;
+		goto err_free_lsc;
 
 	err = netif_set_real_num_tx_queues(netdev, nn->num_tx_rings);
 	if (err)
@@ -1812,19 +1818,11 @@ static int nfp_net_netdev_open(struct net_device *netdev)
 
 	netif_tx_wake_all_queues(netdev);
 
-	err = nfp_net_aux_irq_request(nn, NFP_NET_CFG_LSC, "%s-lsc",
-				      nn->lsc_name, sizeof(nn->lsc_name),
-				      NFP_NET_IRQ_LSC_IDX, nn->lsc_handler);
-	if (err)
-		goto err_stop_tx;
+	enable_irq(nn->irq_entries[NFP_NET_CFG_LSC].vector);
 	nfp_net_read_link_status(nn);
 
 	return 0;
 
-err_stop_tx:
-	netif_tx_disable(netdev);
-	for (r = 0; r < nn->num_r_vecs; r++)
-		nfp_net_tx_flush(nn->r_vecs[r].tx_ring);
 err_disable_napi:
 	while (r--) {
 		napi_disable(&nn->r_vecs[r].napi);
@@ -1834,6 +1832,8 @@ static int nfp_net_netdev_open(struct net_device *netdev)
 	nfp_net_clear_config_and_disable(nn);
 err_free_rings:
 	nfp_net_free_rings(nn);
+err_free_lsc:
+	nfp_net_aux_irq_free(nn, NFP_NET_CFG_LSC, NFP_NET_IRQ_LSC_IDX);
 err_free_exn:
 	nfp_net_aux_irq_free(nn, NFP_NET_CFG_EXN, NFP_NET_IRQ_EXN_IDX);
 	return err;
@@ -1855,7 +1855,7 @@ static int nfp_net_netdev_close(struct net_device *netdev)
 
 	/* Step 1: Disable RX and TX rings from the Linux kernel perspective
 	 */
-	nfp_net_aux_irq_free(nn, NFP_NET_CFG_LSC, NFP_NET_IRQ_LSC_IDX);
+	disable_irq(nn->irq_entries[NFP_NET_CFG_LSC].vector);
 	netif_carrier_off(netdev);
 	nn->link_up = false;
 
@@ -1876,6 +1876,7 @@ static int nfp_net_netdev_close(struct net_device *netdev)
 	}
 
 	nfp_net_free_rings(nn);
+	nfp_net_aux_irq_free(nn, NFP_NET_CFG_LSC, NFP_NET_IRQ_LSC_IDX);
 	nfp_net_aux_irq_free(nn, NFP_NET_CFG_EXN, NFP_NET_IRQ_EXN_IDX);
 
 	nn_dbg(nn, "%s down", netdev->name);