Commit 2c29b235 authored Mar 12, 2015 by Jaeden Amero Committed by David S. Miller Mar 12, 2015

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 <jaeden.amero@ni.com>
Cc: Josh Cartwright <joshc@ni.com>
Cc: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 39361947

drivers/net/ethernet/cadence/macb.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -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,