Subject: RE: [PATCH net-next 5/7] net: txgbe: support switching mode to 1000BASE-X and SGMII

From: Jiawen Wu <[email-masked]>
Date: Tue, 25 Jul 2023 10:29:46 +0800

On Monday, July 24, 2023 6:40 PM, Russell King (Oracle) wrote:
> On Mon, Jul 24, 2023 at 06:23:39PM +0800, Jiawen Wu wrote:
> > @@ -185,6 +186,8 @@ static void txgbe_mac_link_up(struct phylink_config *config,
> >  	struct wx *wx = netdev_priv(to_net_dev(config->dev));
> >  	u32 txcfg, wdg;
> >
> > +	txgbe_enable_sec_tx_path(wx);
> > +
> >  	txcfg = rd32(wx, WX_MAC_TX_CFG);
> >  	txcfg &= ~WX_MAC_TX_CFG_SPEED_MASK;
> >
> > @@ -210,8 +213,20 @@ static void txgbe_mac_link_up(struct phylink_config *config,
> >  	wr32(wx, WX_MAC_WDG_TIMEOUT, wdg);
> >  }
> >
> > +static int txgbe_mac_prepare(struct phylink_config *config, unsigned int mode,
> > +			     phy_interface_t interface)
> > +{
> > +	struct wx *wx = netdev_priv(to_net_dev(config->dev));
> > +
> > +	wr32m(wx, WX_MAC_TX_CFG, WX_MAC_TX_CFG_TE, 0);
> > +	wr32m(wx, WX_MAC_RX_CFG, WX_MAC_RX_CFG_RE, 0);
> > +
> > +	return txgbe_disable_sec_tx_path(wx);
> 
> Is there a reason why the sec_tx_path is enabled/disabled asymmetrically?
> 
> I would expect the transmit path to be disabled in mac_link_down() and
> re-enabled in mac_link_up().
> 
> Alternatively, if it just needs to be disabled for reconfiguration,
> I would expect it to be disabled in mac_prepare() and re-enabled in
> mac_finish().
> 
> The disable in mac_prepare() and enable in mac_link_up() just looks
> rather strange, because it isn't symmetrical.

It needs to be disabled for PCS switch mode, I will move the re-enable to
mac_finish().