[PATCH net-next v2 3/7] net: phy: marvell10g: Use 2500BASEX when using 2.5GBASET

[Maxime Chevallier]

The Marvell Alaska family of PHYs supports 2.5GBaseT and 5GBaseT modes,
as defined in the 802.3bz specification.

Upon establishing a 2.5GBASET link, the PHY will reconfigure it's MII
interface to 2500BASEX.

At 5G, the PHY will reconfigure it's interface to 5GBASE-R, but this
mode isn't supported by any MAC for now.

This was tested with :
 - The 88X3310, which is on the MacchiatoBin
 - The 88E2010, an Alaska PHY that has no fiber interfaces, and is
   limited to 5G maximum speed.

Signed-off-by: Maxime Chevallier <maxime.chevall...@bootlin.com>
---
 drivers/net/phy/marvell10g.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/drivers/net/phy/marvell10g.c b/drivers/net/phy/marvell10g.c
index 821ef1b2f8cc..9342d8c2ff7f 100644
--- a/drivers/net/phy/marvell10g.c
+++ b/drivers/net/phy/marvell10g.c
@@ -235,6 +235,7 @@ static int mv3310_config_init(struct phy_device *phydev)
 {
        /* Check that the PHY interface type is compatible */
        if (phydev->interface != PHY_INTERFACE_MODE_SGMII &&
+           phydev->interface != PHY_INTERFACE_MODE_2500BASEX &&
            phydev->interface != PHY_INTERFACE_MODE_XAUI &&
            phydev->interface != PHY_INTERFACE_MODE_RXAUI &&
            phydev->interface != PHY_INTERFACE_MODE_10GKR)
@@ -313,18 +314,29 @@ static int mv3310_aneg_done(struct phy_device *phydev)
 static void mv3310_update_interface(struct phy_device *phydev)
 {
        if ((phydev->interface == PHY_INTERFACE_MODE_SGMII ||
+            phydev->interface == PHY_INTERFACE_MODE_2500BASEX ||
             phydev->interface == PHY_INTERFACE_MODE_10GKR) && phydev->link) {
                /* The PHY automatically switches its serdes interface (and
-                * active PHYXS instance) between Cisco SGMII and 10GBase-KR
-                * modes according to the speed.  Florian suggests setting
-                * phydev->interface to communicate this to the MAC. Only do
-                * this if we are already in either SGMII or 10GBase-KR mode.
+                * active PHYXS instance) between Cisco SGMII, 10GBase-KR and
+                * 2500BaseX 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.
                 */
-               if (phydev->speed == SPEED_10000)
+               switch (phydev->speed) {
+               case SPEED_10000:
                        phydev->interface = PHY_INTERFACE_MODE_10GKR;
-               else if (phydev->speed >= SPEED_10 &&
-                        phydev->speed < SPEED_10000)
+                       break;
+               case SPEED_2500:
+                       phydev->interface = PHY_INTERFACE_MODE_2500BASEX;
+                       break;
+               case SPEED_1000:
+               case SPEED_100:
+               case SPEED_10:
                        phydev->interface = PHY_INTERFACE_MODE_SGMII;
+                       break;
+               default:
+                       break;
+               }
        }
 }
 
-- 
2.19.2