From 2c29b2354a06f42493ddd2a5eb65962981e666ed Mon Sep 17 00:00:00 2001 From: Jaeden Amero Date: Thu, 12 Mar 2015 18:07:54 -0500 Subject: net/macb: Only adjust tx_clk on link change The PHY state machine (in drivers/net/phy/phy.c) will unconditionally call phydev->adjust_link (macb_handle_link_change) when polling in the PHY_CHANGELINK state. As currently written, macb always ends up requesting a new tx_clk frequency in macb_handle_link_change. It is a waste of time to request a new tx_clk frequency if the link state hasn't changed, as the tx_clk will already be configured properly. Let's only request a new tx_clk clock frequency when necessary. Signed-off-by: Jaeden Amero Cc: Josh Cartwright Cc: Soren Brinkmann Signed-off-by: David S. Miller --- drivers/net/ethernet/cadence/macb.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/net/ethernet/cadence') diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c index f00be585f661..a0a04b3638e6 100644 --- a/drivers/net/ethernet/cadence/macb.c +++ b/drivers/net/ethernet/cadence/macb.c @@ -293,10 +293,13 @@ static void macb_handle_link_change(struct net_device *dev) spin_unlock_irqrestore(&bp->lock, flags); - macb_set_tx_clk(bp->tx_clk, phydev->speed, dev); - if (status_change) { if (phydev->link) { + /* Update the TX clock rate if and only if the link is + * up and there has been a link change. + */ + macb_set_tx_clk(bp->tx_clk, phydev->speed, dev); + netif_carrier_on(dev); netdev_info(dev, "link up (%d/%s)\n", phydev->speed, -- cgit v1.2.3-59-g8ed1b