[PATCH net-next v2 4/5] net: phy: marvell10g: change MACTYPE if underlying MAC does not support it

Marek Behún
2020-10-29T22:25:23Z

RollBall SFPs contain a Marvell 88X3310 PHY, but by default the MACTYPE
is set to 10GBASE-R with Rate Matching.

Some devices (for example those based on Armada 38x) only support up to
2500base-x SerDes modes.

Change the PHY's MACTYPE to 4 (which means changing between 10gbase-r,
5gbase-r, 2500base-x ans SGMII depending on copper speed) if this is the
case (which is infered from phydev->interface).

Signed-off-by: Marek Behún <kabel@kernel.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
---
drivers/net/phy/marvell10g.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)

diff --git a/drivers/net/phy/marvell10g.c b/drivers/net/phy/marvell10g.c
index 1901ba277413..9e8e9aa66972 100644
--- a/drivers/net/phy/marvell10g.c
+++ b/drivers/net/phy/marvell10g.c
@@ -453,6 +453,33 @@ static bool mv3310_has_pma_ngbaset_quirk(struct phy_device *phydev)
MV_PHY_ALASKA_NBT_QUIRK_MASK) == MV_PHY_ALASKA_NBT_QUIRK_REV;
}

+static int mv3310_select_mactype(struct phy_device *phydev)
+{
+ int mac_type, ret;
+
+ /* On some devices the MAC does not support 10G mode, but may support
+ * lower modes, such as SGMII or 2500base-x.
+ * By changing MACTYPE of the PHY to 4 in this case, we ensure that
+ * the MAC will link with the PHY at least for these lower speeds.
+ */
+ switch (phydev->interface) {
+ case PHY_INTERFACE_MODE_SGMII:
+ case PHY_INTERFACE_MODE_2500BASEX:
+ mac_type = 4;
+ break;
+ default:
+ return 0;
+ }
+
+ ret = phy_modify_mmd_changed(phydev, MDIO_MMD_VEND2, MV_V2_PORT_CTRL,
+ MV_V2_PORT_MAC_TYPE_MASK, mac_type);
+ if (ret <= 0)
+ return ret;
+
+ return phy_modify_mmd(phydev, MDIO_MMD_VEND2, MV_V2_PORT_CTRL,
+ MV_V2_PORT_CTRL_SWRST, MV_V2_PORT_CTRL_SWRST);
+}
+
static int mv3310_config_init(struct phy_device *phydev)
{
struct mv3310_priv *priv = dev_get_drvdata(&phydev->mdio.dev);
@@ -474,6 +501,10 @@ static int mv3310_config_init(struct phy_device *phydev)
if (err)
return err;

+ err = mv3310_select_mactype(phydev);
+ if (err)
+ return err;
+
val = phy_read_mmd(phydev, MDIO_MMD_VEND2, MV_V2_PORT_CTRL);
if (val < 0)
return val;
--
2.26.2