Re: [PATCH net-next v2 3/5] net: phy: update in-band AN mode when changing interface by PHY driver

[Choong Yong Liang]

On 4/8/2023 5:02 pm, Russell King (Oracle) wrote:
> On Fri, Aug 04, 2023 at 04:45:25PM +0800, Choong Yong Liang wrote:
> > From: "Tan, Tee Min" <tee.min.tan@xxxxxxxxxxxxxxx>
> >
> > Add cur_link_an_mode into phy_device struct for PHY drivers to
> > communicate the in-band AN mode setting with phylink framework.
> >
> > As there is a mechanism in PHY drivers to switch the PHY interface
> > between SGMII and 2500BaseX according to link speed. In this case,
> > the in-band AN mode should be switching based on the PHY interface
> > as well, if the PHY interface has been changed/updated by PHY driver.
> >
> > For e.g., disable in-band AN in 2500BaseX mode, or enable in-band AN
> > back for SGMII mode (10/100/1000Mbps).
> >
> > Signed-off-by: Tan, Tee Min <tee.min.tan@xxxxxxxxxxxxxxx>
> > Signed-off-by: Choong Yong Liang <yong.liang.choong@xxxxxxxxxxxxxxx>
> > ---
> >   drivers/net/phy/marvell10g.c | 6 ++++++
> >   drivers/net/phy/phylink.c    | 4 ++++
> >   include/linux/phy.h          | 3 +++
> >   3 files changed, 13 insertions(+)
> >
> > diff --git a/drivers/net/phy/marvell10g.c b/drivers/net/phy/marvell10g.c
> > index d4bb90d76881..a9df19278618 100644
> > --- a/drivers/net/phy/marvell10g.c
> > +++ b/drivers/net/phy/marvell10g.c
> > @@ -30,6 +30,7 @@
> >   #include <linux/phy.h>
> >   #include <linux/sfp.h>
> >   #include <linux/netdevice.h>
> > +#include <linux/phylink.h>
> >   
> >   #define MV_PHY_ALASKA_NBT_QUIRK_MASK	0xfffffffe
> >   #define MV_PHY_ALASKA_NBT_QUIRK_REV	(MARVELL_PHY_ID_88X3310 | 0xa)
> > @@ -946,6 +947,9 @@ static void mv3310_update_interface(struct phy_device *phydev)
> >   	 * xaui / rxaui modes according to the speed.
> >   	 * Florian suggests setting phydev->interface to communicate this to the
> >   	 * MAC. Only do this if we are already in one of the above modes.
> > +	 * In-band Auto-negotiation is not supported in 2500BASE-X.
> > +	 * Setting phydev->cur_link_an_mode to communicate this to the
> > +	 * phylink framework.
> >   	 */
> >   	switch (phydev->speed) {
> >   	case SPEED_10000:
> > @@ -956,11 +960,13 @@ static void mv3310_update_interface(struct phy_device *phydev)
> >   		break;
> >   	case SPEED_2500:
> >   		phydev->interface = PHY_INTERFACE_MODE_2500BASEX;
> > +		phydev->cur_link_an_mode = MLO_AN_PHY;
> >   		break;
> >   	case SPEED_1000:
> >   	case SPEED_100:
> >   	case SPEED_10:
> >   		phydev->interface = PHY_INTERFACE_MODE_SGMII;
> > +		phydev->cur_link_an_mode = MLO_AN_INBAND;
> >   		break;
> >   	default:
> >   		break;
> > diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
> > index 4f1c8bb199e9..f9cbb6d7e134 100644
> > --- a/drivers/net/phy/phylink.c
> > +++ b/drivers/net/phy/phylink.c
> > @@ -1720,6 +1720,8 @@ static void phylink_phy_change(struct phy_device *phydev, bool up)
> >   		pl->phy_state.pause |= MLO_PAUSE_RX;
> >   	pl->phy_state.interface = phydev->interface;
> >   	pl->phy_state.link = up;
> > +	pl->cur_link_an_mode = phydev->cur_link_an_mode;
> > +	pl->cfg_link_an_mode = phydev->cur_link_an_mode;
> >   	mutex_unlock(&pl->state_mutex);
> >   
> >   	phylink_run_resolve(pl);
> > @@ -1824,6 +1826,8 @@ static int phylink_bringup_phy(struct phylink *pl, struct phy_device *phy,
> >   	if (pl->config->mac_managed_pm)
> >   		phy->mac_managed_pm = true;
> >   
> > +	pl->phydev->cur_link_an_mode = pl->cur_link_an_mode;
>
> I am really not happy with exposing phylink's AN mode into phylib.
Hi Russell,

Thank you for the feedback.
After conducting further analysis on my end, it appears that this line 
"pl->phydev->cur_link_an_mode = pl->cur_link_an_mode;" is not necessary.
If we remove this line of code, would the implementation of this patch be 
acceptable to you?