net: phy: add support for clause 37 auto-negotiation

This patch adds support for clause 37 1000Base-X auto-negotiation.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Tao Ren <taoren@fb.com>
Tested-by: René van Dorst <opensource@vdorst.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index f1f60bd..fa71998 100644 (file)
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1608,6 +1608,40 @@ static int genphy_config_advert(struct phy_device *phydev)
 }
 
 /**
+ * genphy_c37_config_advert - sanitize and advertise auto-negotiation parameters
+ * @phydev: target phy_device struct
+ *
+ * Description: Writes MII_ADVERTISE with the appropriate values,
+ *   after sanitizing the values to make sure we only advertise
+ *   what is supported.  Returns < 0 on error, 0 if the PHY's advertisement
+ *   hasn't changed, and > 0 if it has changed. This function is intended
+ *   for Clause 37 1000Base-X mode.
+ */
+static int genphy_c37_config_advert(struct phy_device *phydev)
+{
+       u16 adv = 0;
+
+       /* Only allow advertising what this PHY supports */
+       linkmode_and(phydev->advertising, phydev->advertising,
+                    phydev->supported);
+
+       if (linkmode_test_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
+                             phydev->advertising))
+               adv |= ADVERTISE_1000XFULL;
+       if (linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+                             phydev->advertising))
+               adv |= ADVERTISE_1000XPAUSE;
+       if (linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+                             phydev->advertising))
+               adv |= ADVERTISE_1000XPSE_ASYM;
+
+       return phy_modify_changed(phydev, MII_ADVERTISE,
+                                 ADVERTISE_1000XFULL | ADVERTISE_1000XPAUSE |
+                                 ADVERTISE_1000XHALF | ADVERTISE_1000XPSE_ASYM,
+                                 adv);
+}
+
+/**
  * genphy_config_eee_advert - disable unwanted eee mode advertisement
  * @phydev: target phy_device struct
  *
@@ -1716,6 +1750,54 @@ int __genphy_config_aneg(struct phy_device *phydev, bool changed)
 EXPORT_SYMBOL(__genphy_config_aneg);
 
 /**
+ * genphy_c37_config_aneg - restart auto-negotiation or write BMCR
+ * @phydev: target phy_device struct
+ *
+ * Description: If auto-negotiation is enabled, we configure the
+ *   advertising, and then restart auto-negotiation.  If it is not
+ *   enabled, then we write the BMCR. This function is intended
+ *   for use with Clause 37 1000Base-X mode.
+ */
+int genphy_c37_config_aneg(struct phy_device *phydev)
+{
+       int err, changed;
+
+       if (phydev->autoneg != AUTONEG_ENABLE)
+               return genphy_setup_forced(phydev);
+
+       err = phy_modify(phydev, MII_BMCR, BMCR_SPEED1000 | BMCR_SPEED100,
+                        BMCR_SPEED1000);
+       if (err)
+               return err;
+
+       changed = genphy_c37_config_advert(phydev);
+       if (changed < 0) /* error */
+               return changed;
+
+       if (!changed) {
+               /* Advertisement hasn't changed, but maybe aneg was never on to
+                * begin with?  Or maybe phy was isolated?
+                */
+               int ctl = phy_read(phydev, MII_BMCR);
+
+               if (ctl < 0)
+                       return ctl;
+
+               if (!(ctl & BMCR_ANENABLE) || (ctl & BMCR_ISOLATE))
+                       changed = 1; /* do restart aneg */
+       }
+
+       /* Only restart aneg if we are advertising something different
+        * than we were before.
+        */
+       if (changed > 0)
+               return genphy_restart_aneg(phydev);
+
+       return 0;
+}
+EXPORT_SYMBOL(genphy_c37_config_aneg);
+
+/**
  * genphy_aneg_done - return auto-negotiation status
  * @phydev: target phy_device struct
  *
@@ -1887,6 +1969,63 @@ int genphy_read_status(struct phy_device *phydev)
 EXPORT_SYMBOL(genphy_read_status);
 
 /**
+ * genphy_c37_read_status - check the link status and update current link state
+ * @phydev: target phy_device struct
+ *
+ * Description: Check the link, then figure out the current state
+ *   by comparing what we advertise with what the link partner
+ *   advertises. This function is for Clause 37 1000Base-X mode.
+ */
+int genphy_c37_read_status(struct phy_device *phydev)
+{
+       int lpa, err, old_link = phydev->link;
+
+       /* Update the link, but return if there was an error */
+       err = genphy_update_link(phydev);
+       if (err)
+               return err;
+
+       /* why bother the PHY if nothing can have changed */
+       if (phydev->autoneg == AUTONEG_ENABLE && old_link && phydev->link)
+               return 0;
+
+       phydev->duplex = DUPLEX_UNKNOWN;
+       phydev->pause = 0;
+       phydev->asym_pause = 0;
+
+       if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) {
+               lpa = phy_read(phydev, MII_LPA);
+               if (lpa < 0)
+                       return lpa;
+
+               linkmode_mod_bit(ETHTOOL_LINK_MODE_Autoneg_BIT,
+                                phydev->lp_advertising, lpa & LPA_LPACK);
+               linkmode_mod_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
+                                phydev->lp_advertising, lpa & LPA_1000XFULL);
+               linkmode_mod_bit(ETHTOOL_LINK_MODE_Pause_BIT,
+                                phydev->lp_advertising, lpa & LPA_1000XPAUSE);
+               linkmode_mod_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
+                                phydev->lp_advertising,
+                                lpa & LPA_1000XPAUSE_ASYM);
+
+               phy_resolve_aneg_linkmode(phydev);
+       } else if (phydev->autoneg == AUTONEG_DISABLE) {
+               int bmcr = phy_read(phydev, MII_BMCR);
+
+               if (bmcr < 0)
+                       return bmcr;
+
+               if (bmcr & BMCR_FULLDPLX)
+                       phydev->duplex = DUPLEX_FULL;
+               else
+                       phydev->duplex = DUPLEX_HALF;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(genphy_c37_read_status);
+
+/**
  * genphy_soft_reset - software reset the PHY via BMCR_RESET bit
  * @phydev: target phy_device struct
  *

diff --git a/include/linux/phy.h b/include/linux/phy.h
index 9a0e981..78436d5 100644 (file)
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1106,6 +1106,10 @@ int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad,
 int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum,
                                 u16 regnum, u16 val);
 
+/* Clause 37 */
+int genphy_c37_config_aneg(struct phy_device *phydev);
+int genphy_c37_read_status(struct phy_device *phydev);
+
 /* Clause 45 PHY */
 int genphy_c45_restart_aneg(struct phy_device *phydev);
 int genphy_c45_check_and_restart_aneg(struct phy_device *phydev, bool restart);