RDMA/nes: Fix SFP+ link down detection issue with switch port disable

In case of SFP+ PHY, link status check at interrupt processing can
give false results.  For proper link status change detection a delayed
recheck is needed to give nes registers time to settle.  Add a
periodic link status recheck scheduled at interrupt to detect
potential delayed registers state changes.

Addresses: http://bugs.openfabrics.org/bugzilla/show_bug.cgi?id=2117
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/hw/nes/nes.c b/drivers/infiniband/hw/nes/nes.c
index e17f52c..3b4ec32 100644 (file)
--- a/drivers/infiniband/hw/nes/nes.c
+++ b/drivers/infiniband/hw/nes/nes.c
@@ -674,6 +674,8 @@ static int __devinit nes_probe(struct pci_dev *pcidev, const struct pci_device_i
        }
        nes_notifiers_registered++;
 
+       INIT_DELAYED_WORK(&nesdev->work, nes_recheck_link_status);
+
        /* Initialize network devices */
        if ((netdev = nes_netdev_init(nesdev, mmio_regs)) == NULL)
                goto bail7;
@@ -756,6 +758,7 @@ static void __devexit nes_remove(struct pci_dev *pcidev)
        struct nes_device *nesdev = pci_get_drvdata(pcidev);
        struct net_device *netdev;
        int netdev_index = 0;
+       unsigned long flags;
 
                if (nesdev->netdev_count) {
                        netdev = nesdev->netdev[netdev_index];
@@ -782,6 +785,14 @@ static void __devexit nes_remove(struct pci_dev *pcidev)
        free_irq(pcidev->irq, nesdev);
        tasklet_kill(&nesdev->dpc_tasklet);
 
+       spin_lock_irqsave(&nesdev->nesadapter->phy_lock, flags);
+       if (nesdev->link_recheck) {
+               spin_unlock_irqrestore(&nesdev->nesadapter->phy_lock, flags);
+               cancel_delayed_work_sync(&nesdev->work);
+       } else {
+               spin_unlock_irqrestore(&nesdev->nesadapter->phy_lock, flags);
+       }
+
        /* Deallocate the Adapter Structure */
        nes_destroy_adapter(nesdev->nesadapter);
 

diff --git a/drivers/infiniband/hw/nes/nes.h b/drivers/infiniband/hw/nes/nes.h
index b3d145e..6fe7987 100644 (file)
--- a/drivers/infiniband/hw/nes/nes.h
+++ b/drivers/infiniband/hw/nes/nes.h
@@ -268,6 +268,9 @@ struct nes_device {
        u8                     napi_isr_ran;
        u8                     disable_rx_flow_control;
        u8                     disable_tx_flow_control;
+
+       struct delayed_work    work;
+       u8                     link_recheck;
 };
 
 
@@ -507,6 +510,7 @@ void nes_nic_ce_handler(struct nes_device *, struct nes_hw_nic_cq *);
 void nes_iwarp_ce_handler(struct nes_device *, struct nes_hw_cq *);
 int nes_destroy_cqp(struct nes_device *);
 int nes_nic_cm_xmit(struct sk_buff *, struct net_device *);
+void nes_recheck_link_status(struct work_struct *work);
 
 /* nes_nic.c */
 struct net_device *nes_netdev_init(struct nes_device *, void __iomem *);

diff --git a/drivers/infiniband/hw/nes/nes_hw.c b/drivers/infiniband/hw/nes/nes_hw.c
index 2b89b06..8b606fd 100644 (file)
--- a/drivers/infiniband/hw/nes/nes_hw.c
+++ b/drivers/infiniband/hw/nes/nes_hw.c
@@ -2650,6 +2650,13 @@ static void nes_process_mac_intr(struct nes_device *nesdev, u32 mac_number)
                                }
                        }
                }
+               if (nesadapter->phy_type[mac_index] == NES_PHY_TYPE_SFP_D) {
+                       if (nesdev->link_recheck)
+                               cancel_delayed_work(&nesdev->work);
+                       nesdev->link_recheck = 1;
+                       schedule_delayed_work(&nesdev->work,
+                                             NES_LINK_RECHECK_DELAY);
+               }
        }
 
        spin_unlock_irqrestore(&nesadapter->phy_lock, flags);
@@ -2657,6 +2664,80 @@ static void nes_process_mac_intr(struct nes_device *nesdev, u32 mac_number)
        nesadapter->mac_sw_state[mac_number] = NES_MAC_SW_IDLE;
 }
 
+void nes_recheck_link_status(struct work_struct *work)
+{
+       unsigned long flags;
+       struct nes_device *nesdev = container_of(work, struct nes_device, work.work);
+       struct nes_adapter *nesadapter = nesdev->nesadapter;
+       struct nes_vnic *nesvnic;
+       u32 mac_index = nesdev->mac_index;
+       u16 phy_data;
+       u16 temp_phy_data;
+
+       spin_lock_irqsave(&nesadapter->phy_lock, flags);
+
+       /* check link status */
+       nes_read_10G_phy_reg(nesdev, nesadapter->phy_index[mac_index], 1, 0x9003);
+       temp_phy_data = (u16)nes_read_indexed(nesdev, NES_IDX_MAC_MDIO_CONTROL);
+
+       nes_read_10G_phy_reg(nesdev, nesadapter->phy_index[mac_index], 3, 0x0021);
+       nes_read_indexed(nesdev, NES_IDX_MAC_MDIO_CONTROL);
+       nes_read_10G_phy_reg(nesdev, nesadapter->phy_index[mac_index], 3, 0x0021);
+       phy_data = (u16)nes_read_indexed(nesdev, NES_IDX_MAC_MDIO_CONTROL);
+
+       phy_data = (!temp_phy_data && (phy_data == 0x8000)) ? 0x4 : 0x0;
+
+       nes_debug(NES_DBG_PHY, "%s: Phy data = 0x%04X, link was %s.\n",
+               __func__, phy_data,
+               nesadapter->mac_link_down[mac_index] ? "DOWN" : "UP");
+
+       if (phy_data & 0x0004) {
+               nesadapter->mac_link_down[mac_index] = 0;
+               list_for_each_entry(nesvnic, &nesadapter->nesvnic_list[mac_index], list) {
+                       if (nesvnic->linkup == 0) {
+                               printk(PFX "The Link is now up for port %s, netdev %p.\n",
+                                               nesvnic->netdev->name, nesvnic->netdev);
+                               if (netif_queue_stopped(nesvnic->netdev))
+                                       netif_start_queue(nesvnic->netdev);
+                               nesvnic->linkup = 1;
+                               netif_carrier_on(nesvnic->netdev);
+
+                               spin_lock(&nesvnic->port_ibevent_lock);
+                               if (nesdev->iw_status == 0) {
+                                       nesdev->iw_status = 1;
+                                       nes_port_ibevent(nesvnic);
+                               }
+                               spin_unlock(&nesvnic->port_ibevent_lock);
+                       }
+               }
+
+       } else {
+               nesadapter->mac_link_down[mac_index] = 1;
+               list_for_each_entry(nesvnic, &nesadapter->nesvnic_list[mac_index], list) {
+                       if (nesvnic->linkup == 1) {
+                               printk(PFX "The Link is now down for port %s, netdev %p.\n",
+                                               nesvnic->netdev->name, nesvnic->netdev);
+                               if (!(netif_queue_stopped(nesvnic->netdev)))
+                                       netif_stop_queue(nesvnic->netdev);
+                               nesvnic->linkup = 0;
+                               netif_carrier_off(nesvnic->netdev);
+
+                               spin_lock(&nesvnic->port_ibevent_lock);
+                               if (nesdev->iw_status == 1) {
+                                       nesdev->iw_status = 0;
+                                       nes_port_ibevent(nesvnic);
+                               }
+                               spin_unlock(&nesvnic->port_ibevent_lock);
+                       }
+               }
+       }
+       if (nesdev->link_recheck++ < NES_LINK_RECHECK_MAX)
+               schedule_delayed_work(&nesdev->work, NES_LINK_RECHECK_DELAY);
+       else
+               nesdev->link_recheck = 0;
+
+       spin_unlock_irqrestore(&nesadapter->phy_lock, flags);
+}
 
 
 static void nes_nic_napi_ce_handler(struct nes_device *nesdev, struct nes_hw_nic_cq *cq)

diff --git a/drivers/infiniband/hw/nes/nes_hw.h b/drivers/infiniband/hw/nes/nes_hw.h
index 8a9ea9a..d2abe07 100644 (file)
--- a/drivers/infiniband/hw/nes/nes_hw.h
+++ b/drivers/infiniband/hw/nes/nes_hw.h
@@ -1354,6 +1354,10 @@ struct nes_terminate_hdr {
 #define BAD_FRAME_OFFSET       64
 #define CQE_MAJOR_DRV          0x8000
 
+/* Used for link status recheck after interrupt processing */
+#define NES_LINK_RECHECK_DELAY msecs_to_jiffies(50)
+#define NES_LINK_RECHECK_MAX   60
+
 #define nes_vlan_rx vlan_hwaccel_receive_skb
 #define nes_netif_rx netif_receive_skb