[PATCH net-next v3 9/9] net: wangxun: implement pci_error_handlers ops

[Jiawen Wu <jiawenwu@trustnetic.com>]

Support AER driver to handle the PCIe errors.

Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
---
 drivers/net/ethernet/wangxun/libwx/wx_err.c   | 102 ++++++++++++++++++
 drivers/net/ethernet/wangxun/libwx/wx_err.h   |   2 +
 drivers/net/ethernet/wangxun/libwx/wx_lib.c   |   3 +-
 drivers/net/ethernet/wangxun/libwx/wx_type.h  |   1 +
 drivers/net/ethernet/wangxun/ngbe/ngbe_main.c |   5 +-
 .../net/ethernet/wangxun/txgbe/txgbe_main.c   |   5 +-
 6 files changed, 115 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/wangxun/libwx/wx_err.c b/drivers/net/ethernet/wangxun/libwx/wx_err.c
index bb77bdce69d2..86b318647a3c 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_err.c
+++ b/drivers/net/ethernet/wangxun/libwx/wx_err.c
@@ -3,11 +3,113 @@
 
 #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;
+
+	netdev = wx->netdev;
+	if (!netif_device_present(netdev))
+		return PCI_ERS_RESULT_DISCONNECT;
+
+	rtnl_lock();
+	netif_device_detach(netdev);
+
+	if (netif_running(netdev))
+		wx->close_suspend(wx);
+
+	if (state == pci_channel_io_perm_failure) {
+		rtnl_unlock();
+		return PCI_ERS_RESULT_DISCONNECT;
+	}
+
+	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 bar access done before reset. */
+		smp_mb__before_atomic();
+		clear_bit(WX_STATE_DISABLED, wx->state);
+		pci_set_master(pdev);
+		pci_restore_state(pdev);
+		pci_save_state(pdev);
+		pci_wake_from_d3(pdev, false);
+
+		wx->do_reset(wx->netdev, false);
+		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;
+
+	netdev = wx->netdev;
+	rtnl_lock();
+	if (netif_running(netdev))
+		netdev->netdev_ops->ndo_open(netdev);
+
+	netif_device_attach(netdev);
+	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_reset_subtask(struct wx *wx)
 {
 	if (!test_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 e317e6c8d928..8b1a7863b5b1 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_handle_errors_subtask(struct wx *wx);
 void wx_tx_timeout(struct net_device *netdev, unsigned int txqueue);
 void wx_handle_tx_hang(struct wx_ring *tx_ring, unsigned int next);
diff --git a/drivers/net/ethernet/wangxun/libwx/wx_lib.c b/drivers/net/ethernet/wangxun/libwx/wx_lib.c
index 5a21478a592b..1cd73b424d7f 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_lib.c
+++ b/drivers/net/ethernet/wangxun/libwx/wx_lib.c
@@ -3418,7 +3418,8 @@ static void wx_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);
 }
 
 int wx_suspend(struct pci_dev *pdev, pm_message_t state)
diff --git a/drivers/net/ethernet/wangxun/libwx/wx_type.h b/drivers/net/ethernet/wangxun/libwx/wx_type.h
index 434a582393d7..142b166117fa 100644
--- a/drivers/net/ethernet/wangxun/libwx/wx_type.h
+++ b/drivers/net/ethernet/wangxun/libwx/wx_type.h
@@ -1196,6 +1196,7 @@ 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 e0f5d3b49db7..18bd627f63db 100644
--- a/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
+++ b/drivers/net/ethernet/wangxun/ngbe/ngbe_main.c
@@ -819,6 +819,7 @@ static int ngbe_probe(struct pci_dev *pdev,
 		goto err_register;
 
 	pci_set_drvdata(pdev, wx);
+	pci_save_state(pdev);
 
 	return 0;
 
@@ -869,7 +870,8 @@ 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 struct pci_driver ngbe_driver = {
@@ -881,6 +883,7 @@ static struct pci_driver ngbe_driver = {
 	.resume   = wx_resume,
 	.shutdown = wx_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 d4f87fbb9565..c9fdad7f0df2 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_main.c
@@ -886,6 +886,7 @@ 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);
 
@@ -956,7 +957,8 @@ 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 = {
@@ -968,6 +970,7 @@ static struct pci_driver txgbe_driver = {
 	.resume   = wx_resume,
 	.shutdown = wx_shutdown,
 	.sriov_configure = wx_pci_sriov_configure,
+	.err_handler = &wx_err_handler,
 };
 
 module_pci_driver(txgbe_driver);
-- 
2.48.1