[PATCH net-next v10 2/3] net: phy: add support for clause 37 auto-negotiation

From: rentao . bupt
Date: Tue Oct 22 2019 - 14:31:47 EST


From: Heiner Kallweit <hkallweit1@xxxxxxxxx>

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

Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
Signed-off-by: Tao Ren <taoren@xxxxxx>
Tested-by: Renà van Dorst <opensource@xxxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
---
No change in v9/v10.
Changes in v8:
- Rebased the patch on top of net-next HEAD.
Changes in v7:
- Update "if (AUTONEG_ENABLE != phydev->autoneg)" to
"if (phydev->autoneg != AUTONEG_ENABLE)" so checkpatch.pl is happy.
Changes in v6:
- add "Signed-off-by: Tao Ren <taoren@xxxxxx>"
Changes in v1-v5:
- nothing changed. It's given v5 just to align with the version of
patch series.

drivers/net/phy/phy_device.c | 139 +++++++++++++++++++++++++++++++++++
include/linux/phy.h | 4 +
2 files changed, 143 insertions(+)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index f1f60bd4865a..fa71998fea51 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1607,6 +1607,40 @@ static int genphy_config_advert(struct phy_device *phydev)
return changed;
}

+/**
+ * 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
@@ -1715,6 +1749,54 @@ 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
@@ -1886,6 +1968,63 @@ 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 9a0e981df502..78436d58ce7c 100644
--- 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);
--
2.17.1