Support AER driver to handle the PCIe errors.

Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
---
 drivers/net/ethernet/wangxun/libwx/wx_err.c   | 111 ++++++++++++++++++
 drivers/net/ethernet/wangxun/libwx/wx_err.h   |   2 +
 drivers/net/ethernet/wangxun/libwx/wx_type.h  |   1 +
 drivers/net/ethernet/wangxun/ngbe/ngbe_main.c |   9 +-
 .../net/ethernet/wangxun/txgbe/txgbe_main.c   |   8 +-
 5 files changed, 127 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/wangxun/libwx/wx_err.c b/drivers/net/ethernet/wangxun/libwx/wx_err.c
index e249cea874be..ae5d14071f3d 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_err.c
+++ b/drivers/net/ethernet/wangxun/libwx/wx_err.c

@@ -4,11 +4,122 @@
 
 #include <linux/netdevice.h>
 #include <linux/pci.h>
+#include <linux/aer.h>
 
 #include "wx_type.h"
 #include "wx_lib.h"
 #include "wx_err.h"
 
+/**
+ * wx_io_error_detected - called when PCI error is detected
+ * @pdev: Pointer to PCI device
+ * @state: The current pci connection state
+ *
+ * Return: pci_ers_result_t.
+ *
+ * This function is called after a PCI bus error affecting
+ * this device has been detected.
+ */
+static pci_ers_result_t wx_io_error_detected(struct pci_dev *pdev,
+					     pci_channel_state_t state)
+{
+	struct wx *wx = pci_get_drvdata(pdev);
+	struct net_device *netdev;
+
+	if (!wx)
+		return PCI_ERS_RESULT_DISCONNECT;
+
+	netdev = wx->netdev;
+	if (!netif_device_present(netdev))
+		return PCI_ERS_RESULT_DISCONNECT;
+
+	if (state == pci_channel_io_perm_failure)
+		return PCI_ERS_RESULT_DISCONNECT;
+
+	rtnl_lock();
+	netif_device_detach(netdev);

+
+	if (netif_running(netdev) && wx->soft_quiesce)
+		wx->soft_quiesce(wx);
+
+	if (!test_and_set_bit(WX_STATE_DISABLED, wx->state))
+		pci_disable_device(pdev);
+	rtnl_unlock();
+
+	/* Request a slot reset. */
+	return PCI_ERS_RESULT_NEED_RESET;
+}
+
+/**
+ * wx_io_slot_reset - called after the pci bus has been reset.
+ * @pdev: Pointer to PCI device
+ *
+ * Return: pci_ers_result_t.
+ *
+ * Restart the card from scratch, as if from a cold-boot.
+ */
+static pci_ers_result_t wx_io_slot_reset(struct pci_dev *pdev)
+{
+	struct wx *wx = pci_get_drvdata(pdev);
+	pci_ers_result_t result;
+
+	if (pci_enable_device_mem(pdev)) {
+		wx_err(wx, "Cannot re-enable PCI device after reset.\n");
+		result = PCI_ERS_RESULT_DISCONNECT;
+	} else {
+		/* make all memory operations done before clearing the flag */
+		smp_mb__before_atomic();
+		clear_bit(WX_STATE_DISABLED, wx->state);
+		pci_set_master(pdev);
+		pci_restore_state(pdev);
+		pci_wake_from_d3(pdev, false);
+
+		rtnl_lock();
+		if (wx->do_reset)
+			wx->do_reset(wx->netdev, false);
+		rtnl_unlock();
+		result = PCI_ERS_RESULT_RECOVERED;
+	}
+
+	pci_aer_clear_nonfatal_status(pdev);
+
+	return result;
+}
+
+/**
+ * wx_io_resume - called when traffic can start flowing again.
+ * @pdev: Pointer to PCI device
+ *
+ * This callback is called when the error recovery driver tells us that
+ * its OK to resume normal operation.
+ */
+static void wx_io_resume(struct pci_dev *pdev)
+{
+	struct wx *wx = pci_get_drvdata(pdev);
+	struct net_device *netdev;
+	int err;
+
+	netdev = wx->netdev;
+	rtnl_lock();
+	if (netif_running(netdev)) {
+		err = netdev->netdev_ops->ndo_open(netdev);
+		if (err) {
+			wx_err(wx, "Failed to open netdev after reset\n");
+			goto out;
+		}
+	}
+	netif_device_attach(netdev);
+out:
+	rtnl_unlock();
+}
+
+const struct pci_error_handlers wx_err_handler = {
+	.error_detected = wx_io_error_detected,
+	.slot_reset = wx_io_slot_reset,
+	.resume = wx_io_resume,
+};
+EXPORT_SYMBOL(wx_err_handler);
+
 static void wx_pf_reset_subtask(struct wx *wx)
 {
 	if (!test_and_clear_bit(WX_FLAG_NEED_PF_RESET, wx->flags))

diff --git a/drivers/net/ethernet/wangxun/libwx/wx_err.h b/drivers/net/ethernet/wangxun/libwx/wx_err.h
index a529bf54eeac..de5d02316230 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_err.h
+++ b/drivers/net/ethernet/wangxun/libwx/wx_err.h

@@ -7,6 +7,8 @@
 #ifndef _WX_ERR_H_
 #define _WX_ERR_H_
 
+extern const struct pci_error_handlers wx_err_handler;
+
 void wx_check_err_subtask(struct wx *wx);
 int wx_init_err_task(struct wx *wx);
 void wx_check_tx_hang_subtask(struct wx *wx);

diff --git a/drivers/net/ethernet/wangxun/libwx/wx_type.h b/drivers/net/ethernet/wangxun/libwx/wx_type.h
index 1b25a52188f7..778e186e4555 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_type.h
+++ b/drivers/net/ethernet/wangxun/libwx/wx_type.h

@@ -1221,6 +1221,7 @@ enum wx_state {
 	WX_STATE_PTP_RUNNING,
 	WX_STATE_PTP_TX_IN_PROGRESS,
 	WX_STATE_SERVICE_SCHED,
+	WX_STATE_DISABLED,
 	WX_STATE_NBITS		/* must be last */
 };
 

diff --git a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
index 2484d3177034..8e5a708ea809 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c

@@ -589,7 +589,8 @@ static void ngbe_dev_shutdown(struct pci_dev *pdev, bool *enable_wake)
 	*enable_wake = !!wufc;
 	wx_control_hw(wx, false);
 
-	pci_disable_device(pdev);
+	if (!test_and_set_bit(WX_STATE_DISABLED, wx->state))
+		pci_disable_device(pdev);
 }
 
 static void ngbe_shutdown(struct pci_dev *pdev)

@@ -879,6 +880,7 @@ static int ngbe_probe(struct pci_dev *pdev,
 		goto err_register;
 
 	pci_set_drvdata(pdev, wx);
+	pci_save_state(pdev);
 
 	return 0;
 

@@ -934,7 +936,8 @@ static void ngbe_remove(struct pci_dev *pdev)
 	kfree(wx->mac_table);
 	wx_clear_interrupt_scheme(wx);
 
-	pci_disable_device(pdev);
+	if (!test_and_set_bit(WX_STATE_DISABLED, wx->state))
+		pci_disable_device(pdev);
 }
 
 static int ngbe_suspend(struct pci_dev *pdev, pm_message_t state)

@@ -961,6 +964,7 @@ static int ngbe_resume(struct pci_dev *pdev)
 		wx_err(wx, "Cannot enable PCI device from suspend\n");
 		return err;
 	}
+	clear_bit(WX_STATE_DISABLED, wx->state);
 	pci_set_master(pdev);
 	device_wakeup_disable(&pdev->dev);
 

@@ -985,6 +989,7 @@ static struct pci_driver ngbe_driver = {
 	.resume   = ngbe_resume,
 	.shutdown = ngbe_shutdown,
 	.sriov_configure = wx_pci_sriov_configure,
+	.err_handler = &wx_err_handler,
 };
 
 module_pci_driver(ngbe_driver);

diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
index 816aba4a9099..e913e3553ced 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c

@@ -570,7 +570,8 @@ static void txgbe_dev_shutdown(struct pci_dev *pdev)
 
 	wx_control_hw(wx, false);
 
-	pci_disable_device(pdev);
+	if (!test_and_set_bit(WX_STATE_DISABLED, wx->state))
+		pci_disable_device(pdev);
 }
 
 static void txgbe_shutdown(struct pci_dev *pdev)

@@ -922,6 +923,7 @@ static int txgbe_probe(struct pci_dev *pdev,
 		goto err_remove_phy;
 
 	pci_set_drvdata(pdev, wx);
+	pci_save_state(pdev);
 
 	netif_tx_stop_all_queues(netdev);
 

@@ -996,7 +998,8 @@ static void txgbe_remove(struct pci_dev *pdev)
 	kfree(wx->mac_table);
 	wx_clear_interrupt_scheme(wx);
 
-	pci_disable_device(pdev);
+	if (!test_and_set_bit(WX_STATE_DISABLED, wx->state))
+		pci_disable_device(pdev);
 }
 
 static struct pci_driver txgbe_driver = {

@@ -1006,6 +1009,7 @@ static struct pci_driver txgbe_driver = {
 	.remove   = txgbe_remove,
 	.shutdown = txgbe_shutdown,
 	.sriov_configure = wx_pci_sriov_configure,
+	.err_handler = &wx_err_handler,
 };
 
 module_pci_driver(txgbe_driver);

-- 
2.51.0