diff --git a/drivers/net/ethernet/spacemit/k1_emac.c b/drivers/net/ethernet/spacemit/k1_emac.c index 220eb5ce7583..88e9424d2d51 100644 --- a/drivers/net/ethernet/spacemit/k1_emac.c +++ b/drivers/net/ethernet/spacemit/k1_emac.c @@ -1099,7 +1099,13 @@ static int emac_read_stat_cnt(struct emac_priv *priv, u8 cnt, u32 *res, 100, 10000); if (ret) { - netdev_err(priv->ndev, "Read stat timeout\n"); + /* + * This could be caused by the PHY stopping its refclk even when + * the link is up, for power saving. See also comments in + * emac_stats_update(). + */ + dev_err_ratelimited(&priv->ndev->dev, + "Read stat timeout. PHY clock stopped?\n"); return ret; } @@ -1147,17 +1153,25 @@ static void emac_stats_update(struct emac_priv *priv) assert_spin_locked(&priv->stats_lock); - if (!netif_running(priv->ndev) || !netif_device_present(priv->ndev)) { - /* Not up, don't try to update */ + /* + * We can't read statistics if the interface is not up. Also, some PHYs + * stop their reference clocks for link down power saving, which also + * causes reading statistics to time out. Don't update and don't + * reschedule in these cases. + */ + if (!netif_running(priv->ndev) || + !netif_carrier_ok(priv->ndev) || + !netif_device_present(priv->ndev)) { return; } for (i = 0; i < sizeof(priv->tx_stats) / sizeof(*tx_stats); i++) { /* - * If reading stats times out, everything is broken and there's - * nothing we can do. Reading statistics also can't return an - * error, so just return without updating and without - * rescheduling. + * If reading stats times out anyway, the stat registers will be + * stuck, and we can't really recover from that. + * + * Reading statistics also can't return an error, so just return + * without updating and without rescheduling. */ if (emac_tx_read_stat_cnt(priv, i, &res)) return; @@ -1636,6 +1650,12 @@ static void emac_adjust_link(struct net_device *dev) emac_wr(priv, MAC_GLOBAL_CONTROL, ctrl); emac_set_fc_autoneg(priv); + + /* + * Reschedule stats updates now that link is up. See comments in + * emac_stats_update(). + */ + mod_timer(&priv->stats_timer, jiffies); } phy_print_status(phydev);