[PATCH net-next v7 7/9] net: wangxun: schedule hardware stats update in watchdog

[Jiawen Wu <jiawenwu@trustnetic.com>]

Hardware statistics should be updated periodically in the watchdog to
prevent 32-bit registers from overflowing. This is also required for the
upcoming pause frame accounting logic, which relies on regular statistics
sampling.

Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
---
 drivers/net/ethernet/wangxun/libwx/wx_hw.c    |  9 +++++
 drivers/net/ethernet/wangxun/libwx/wx_type.h  |  1 +
 drivers/net/ethernet/wangxun/ngbe/ngbe_main.c | 36 ++++++++++++++++++-
 .../net/ethernet/wangxun/txgbe/txgbe_main.c   |  1 +
 4 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/wangxun/libwx/wx_hw.c b/drivers/net/ethernet/wangxun/libwx/wx_hw.c
index 05731a50d85f..31259f69c0e2 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_hw.c
+++ b/drivers/net/ethernet/wangxun/libwx/wx_hw.c
@@ -2513,6 +2513,7 @@ int wx_sw_init(struct wx *wx)
 		return -ENOMEM;
 	}
 
+	spin_lock_init(&wx->hw_stats_lock);
 	mutex_init(&wx->reset_lock);
 	bitmap_zero(wx->state, WX_STATE_NBITS);
 	bitmap_zero(wx->flags, WX_PF_FLAGS_NBITS);
@@ -2845,6 +2846,12 @@ void wx_update_stats(struct wx *wx)
 	u64 restart_queue = 0, tx_busy = 0;
 	u32 i;
 
+	if (!netif_running(wx->netdev) ||
+	    test_bit(WX_STATE_RESETTING, wx->state))
+		return;
+
+	spin_lock(&wx->hw_stats_lock);
+
 	/* gather some stats to the wx struct that are per queue */
 	for (i = 0; i < wx->num_rx_queues; i++) {
 		struct wx_ring *rx_ring = wx->rx_ring[i];
@@ -2913,6 +2920,8 @@ void wx_update_stats(struct wx *wx)
 	for (i = wx->num_vfs * wx->num_rx_queues_per_pool;
 	     i < wx->mac.max_rx_queues; i++)
 		hwstats->qmprc += rd32(wx, WX_PX_MPRC(i));
+
+	spin_unlock(&wx->hw_stats_lock);
 }
 EXPORT_SYMBOL(wx_update_stats);
 
diff --git a/drivers/net/ethernet/wangxun/libwx/wx_type.h b/drivers/net/ethernet/wangxun/libwx/wx_type.h
index 0fbdda63b141..7831c5035be8 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_type.h
+++ b/drivers/net/ethernet/wangxun/libwx/wx_type.h
@@ -1354,6 +1354,7 @@ struct wx {
 	bool default_up;
 
 	struct wx_hw_stats stats;
+	spinlock_t hw_stats_lock; /* spinlock for accessing to hw stats */
 	u64 tx_busy;
 	u64 non_eop_descs;
 	u64 restart_queue;
diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
index 8c9d505721b1..d8e3827a8b1f 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
@@ -138,6 +138,26 @@ static int ngbe_sw_init(struct wx *wx)
 	return 0;
 }
 
+/**
+ * ngbe_service_task - manages and runs subtasks
+ * @work: pointer to work_struct containing our data
+ **/
+static void ngbe_service_task(struct work_struct *work)
+{
+	struct wx *wx = container_of(work, struct wx, service_task);
+
+	wx_update_stats(wx);
+
+	wx_service_event_complete(wx);
+}
+
+static void ngbe_init_service(struct wx *wx)
+{
+	timer_setup(&wx->service_timer, wx_service_timer, 0);
+	INIT_WORK(&wx->service_task, ngbe_service_task);
+	clear_bit(WX_STATE_SERVICE_SCHED, wx->state);
+}
+
 /**
  * ngbe_irq_enable - Enable default interrupt generation settings
  * @wx: board private structure
@@ -368,6 +388,10 @@ static void ngbe_disable_device(struct wx *wx)
 	wx_napi_disable_all(wx);
 	netif_tx_stop_all_queues(netdev);
 	netif_tx_disable(netdev);
+
+	timer_delete_sync(&wx->service_timer);
+	cancel_work_sync(&wx->service_task);
+
 	if (wx->gpio_ctrl)
 		ngbe_sfp_modules_txrx_powerctl(wx, false);
 	wx_irq_disable(wx);
@@ -407,6 +431,7 @@ void ngbe_up(struct wx *wx)
 	wx_napi_enable_all(wx);
 	/* enable transmits */
 	netif_tx_start_all_queues(wx->netdev);
+	mod_timer(&wx->service_timer, jiffies);
 
 	/* clear any pending interrupts, may auto mask */
 	rd32(wx, WX_PX_IC(0));
@@ -770,9 +795,11 @@ static int ngbe_probe(struct pci_dev *pdev,
 	eth_hw_addr_set(netdev, wx->mac.perm_addr);
 	wx_mac_set_default_filter(wx, wx->mac.perm_addr);
 
+	ngbe_init_service(wx);
+
 	err = wx_init_interrupt_scheme(wx);
 	if (err)
-		goto err_free_mac_table;
+		goto err_cancel_service;
 
 	/* phy Interface Configuration */
 	err = ngbe_mdio_init(wx);
@@ -792,6 +819,9 @@ static int ngbe_probe(struct pci_dev *pdev,
 	wx_control_hw(wx, false);
 err_clear_interrupt_scheme:
 	wx_clear_interrupt_scheme(wx);
+err_cancel_service:
+	timer_delete_sync(&wx->service_timer);
+	cancel_work_sync(&wx->service_task);
 err_free_mac_table:
 	kfree(wx->rss_key);
 	kfree(wx->mac_table);
@@ -820,6 +850,10 @@ static void ngbe_remove(struct pci_dev *pdev)
 	netdev = wx->netdev;
 	wx_disable_sriov(wx);
 	unregister_netdev(netdev);
+
+	timer_shutdown_sync(&wx->service_timer);
+	cancel_work_sync(&wx->service_task);
+
 	phylink_destroy(wx->phylink);
 	pci_release_selected_regions(pdev,
 				     pci_select_bars(pdev, IORESOURCE_MEM));
diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
index 0dd128aa18da..ec32a5f422f2 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
@@ -130,6 +130,7 @@ static void txgbe_service_task(struct work_struct *work)
 
 	txgbe_module_detection_subtask(wx);
 	txgbe_link_config_subtask(wx);
+	wx_update_stats(wx);
 
 	wx_service_event_complete(wx);
 }
-- 
2.48.1