Link speed changes require a full HW reset. This isn't done
properly at the moment. It will involve delays and thus isn't
suitable to do from the link poll callback.
So let's create a reset_task that we can queue up when the
link changes. It will be useful for various cases of error
handling as well.
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
--
v2. Fix lock ordering
Add mdio_bus mutex
---
drivers/net/ethernet/faraday/ftgmac100.c | 87 +++++++++++++++++++++++++++-----
1 file changed, 74 insertions(+), 13 deletions(-)
diff --git a/drivers/net/ethernet/faraday/ftgmac100.c
b/drivers/net/ethernet/faraday/ftgmac100.c
index 36f2905..61f02bf 100644
--- a/drivers/net/ethernet/faraday/ftgmac100.c
+++ b/drivers/net/ethernet/faraday/ftgmac100.c
@@ -74,6 +74,7 @@ struct ftgmac100 {
struct device *dev;
struct ncsi_dev *ndev;
struct napi_struct napi;
+ struct work_struct reset_task;
struct mii_bus *mii_bus;
/* Link management */
@@ -872,7 +873,6 @@ static void ftgmac100_adjust_link(struct net_device *netdev)
struct ftgmac100 *priv = netdev_priv(netdev);
struct phy_device *phydev = netdev->phydev;
int new_speed;
- int ier;
/* We store "no link" as speed 0 */
if (!phydev->link)
@@ -897,20 +897,11 @@ static void ftgmac100_adjust_link(struct net_device
*netdev)
if (!new_speed)
return;
- ier = ioread32(priv->base + FTGMAC100_OFFSET_IER);
-
- /* disable all interrupts */
+ /* Disable all interrupts */
iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
- netif_stop_queue(netdev);
- ftgmac100_stop_hw(priv);
-
- netif_start_queue(netdev);
- ftgmac100_init_hw(priv);
- ftgmac100_start_hw(priv);
-
- /* re-enable interrupts */
- iowrite32(ier, priv->base + FTGMAC100_OFFSET_IER);
+ /* Reset the adapter asynchronously */
+ schedule_work(&priv->reset_task);
}
static int ftgmac100_mii_probe(struct ftgmac100 *priv)
@@ -1135,6 +1126,61 @@ static int ftgmac100_init_all(struct ftgmac100 *priv,
bool ignore_alloc_err)
return err;
}
+static void ftgmac100_reset_task(struct work_struct *work)
+{
+ struct ftgmac100 *priv = container_of(work, struct ftgmac100,
+ reset_task);
+ struct net_device *netdev = priv->netdev;
+ int err;
+
+ netdev_dbg(netdev, "Resetting NIC...\n");
+
+ /* Lock the world */
+ rtnl_lock();
+ if (netdev->phydev)
+ mutex_lock(&netdev->phydev->lock);
+ if (priv->mii_bus)
+ mutex_lock(&priv->mii_bus->mdio_lock);
+
+
+ /* Check if the interface is still up */
+ if (!netif_running(netdev))
+ goto bail;
+
+ /* Stop the network stack */
+ netif_trans_update(netdev);
+ napi_disable(&priv->napi);
+ netif_tx_disable(netdev);
+
+ /* Stop and reset the MAC */
+ ftgmac100_stop_hw(priv);
+ err = ftgmac100_reset_hw(priv);
+ if (err) {
+ /* Not much we can do ... it might come back... */
+ netdev_err(netdev, "attempting to continue...\n");
+ }
+
+ /* Free all rx and tx buffers */
+ ftgmac100_free_buffers(priv);
+
+ /* The ring pointers have been reset in HW, reflect this here */
+ priv->rx_pointer = 0;
+ priv->tx_clean_pointer = 0;
+ priv->tx_pointer = 0;
+ priv->tx_pending = 0;
+
+ /* Setup everything again and restart chip */
+ ftgmac100_init_all(priv, true);
+
+ netdev_dbg(netdev, "Reset done !\n");
+ bail:
+ if (priv->mii_bus)
+ mutex_unlock(&priv->mii_bus->mdio_lock);
+ if (netdev->phydev)
+ mutex_unlock(&netdev->phydev->lock);
+ rtnl_unlock();
+}
+
static int ftgmac100_open(struct net_device *netdev)
{
struct ftgmac100 *priv = netdev_priv(netdev);
@@ -1220,6 +1266,14 @@ static int ftgmac100_stop(struct net_device *netdev)
{
struct ftgmac100 *priv = netdev_priv(netdev);
+ /* Note about the reset task: We are called with the rtnl lock
+ * held, so we are synchronized against the core of the reset
+ * task. We must not try to synchronously cancel it otherwise
+ * we can deadlock. But since it will test for netif_running()
+ * which has already been cleared by the net core, we don't
+ * anything special to do.
+ */
+
/* disable all interrupts */
iowrite32(0, priv->base + FTGMAC100_OFFSET_IER);
@@ -1395,6 +1449,7 @@ static int ftgmac100_probe(struct platform_device *pdev)
priv = netdev_priv(netdev);
priv->netdev = netdev;
priv->dev = &pdev->dev;
+ INIT_WORK(&priv->reset_task, ftgmac100_reset_task);
spin_lock_init(&priv->tx_lock);
@@ -1498,6 +1553,12 @@ static int ftgmac100_remove(struct platform_device *pdev)
priv = netdev_priv(netdev);
unregister_netdev(netdev);
+
+ /* There's a small chance the reset task will have been re-queued,
+ * during stop, make sure it's gone before we free the structure.
+ */
+ cancel_work_sync(&priv->reset_task);
+
ftgmac100_destroy_mdio(netdev);
iounmap(priv->base);
--
2.9.3
