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> --- drivers/net/ethernet/faraday/ftgmac100.c | 85 +++++++++++++++++++++++++++----- 1 file changed, 72 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c index 96c6bc2..d616c0a 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) @@ -899,20 +899,11 @@ static void ftgmac100_adjust_link(struct net_device *netdev) priv->cur_speed = new_speed; priv->cur_duplex = phydev->duplex; - 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) @@ -1137,6 +1128,59 @@ 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"); + + /* Block PHY polling */ + if (netdev->phydev) + mutex_lock(&netdev->phydev->lock); + + rtnl_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: + rtnl_unlock(); + + /* Unblock PHY polling */ + if (netdev->phydev) + mutex_unlock(&netdev->phydev->lock); +} + static int ftgmac100_open(struct net_device *netdev) { struct ftgmac100 *priv = netdev_priv(netdev); @@ -1222,6 +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); @@ -1397,6 +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); @@ -1500,6 +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