[PATCH net-next v3 1/4] net: phy: add an option to disable EEE advertisement
From: jbrunet@baylibre.com (Jerome Brunet)
Date: 2016-11-28 09:47:15
Also in:
linux-amlogic, linux-devicetree, lkml, netdev
Subsystem:
ethernet phy library, networking drivers, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
This patch adds an option to disable EEE advertisement in the generic PHY by providing a mask of prohibited modes corresponding to the value found in the MDIO_AN_EEE_ADV register. On some platforms, PHY Low power idle seems to be causing issues, even breaking the link some cases. The patch provides a convenient way for these platforms to disable EEE advertisement and work around the issue. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> --- drivers/net/phy/phy.c | 3 ++ drivers/net/phy/phy_device.c | 80 +++++++++++++++++++++++++++++++++++++++----- include/linux/phy.h | 3 ++ 3 files changed, 77 insertions(+), 9 deletions(-)
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 73adbaa9ac86..a3981cc6448a 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c@@ -1396,6 +1396,9 @@ int phy_ethtool_set_eee(struct phy_device *phydev, struct ethtool_eee *data) { int val = ethtool_adv_to_mmd_eee_adv_t(data->advertised); + /* Mask prohibited EEE modes */ + val &= ~phydev->eee_broken_modes; + phy_write_mmd_indirect(phydev, MDIO_AN_EEE_ADV, MDIO_MMD_AN, val); return 0;
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index ba86c191a13e..83e52f1b80f2 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c@@ -1121,6 +1121,43 @@ static int genphy_config_advert(struct phy_device *phydev) } /** + * genphy_config_eee_advert - disable unwanted eee mode advertisement + * @phydev: target phy_device struct + * + * Description: Writes MDIO_AN_EEE_ADV after disabling unsupported energy + * efficent ethernet modes. Returns 0 if the PHY's advertisement hasn't + * changed, and 1 if it has changed. + */ +static int genphy_config_eee_advert(struct phy_device *phydev) +{ + u32 broken = phydev->eee_broken_modes; + u32 old_adv, adv; + + /* Nothing to disable */ + if (!broken) + return 0; + + /* If the following call fails, we assume that EEE is not + * supported by the phy. If we read 0, EEE is not advertised + * In both case, we don't need to continue + */ + adv = phy_read_mmd_indirect(phydev, MDIO_AN_EEE_ADV, MDIO_MMD_AN); + if (adv <= 0) + return 0; + + old_adv = adv; + adv &= ~broken; + + /* Advertising remains unchanged with the broken mask */ + if (old_adv == adv) + return 0; + + phy_write_mmd_indirect(phydev, MDIO_AN_EEE_ADV, MDIO_MMD_AN, adv); + + return 1; +} + +/** * genphy_setup_forced - configures/forces speed/duplex from @phydev * @phydev: target phy_device struct *
@@ -1178,15 +1215,20 @@ EXPORT_SYMBOL(genphy_restart_aneg); */ int genphy_config_aneg(struct phy_device *phydev) { - int result; + int err, changed; + + changed = genphy_config_eee_advert(phydev); if (AUTONEG_ENABLE != phydev->autoneg) return genphy_setup_forced(phydev); - result = genphy_config_advert(phydev); - if (result < 0) /* error */ - return result; - if (result == 0) { + err = genphy_config_advert(phydev); + if (err < 0) /* error */ + return err; + + changed |= err; + + if (changed == 0) { /* Advertisement hasn't changed, but maybe aneg was never on to * begin with? Or maybe phy was isolated? */
@@ -1196,16 +1238,16 @@ int genphy_config_aneg(struct phy_device *phydev) return ctl; if (!(ctl & BMCR_ANENABLE) || (ctl & BMCR_ISOLATE)) - result = 1; /* do restart aneg */ + changed = 1; /* do restart aneg */ } /* Only restart aneg if we are advertising something different * than we were before. */ - if (result > 0) - result = genphy_restart_aneg(phydev); + if (changed > 0) + return genphy_restart_aneg(phydev); - return result; + return 0; } EXPORT_SYMBOL(genphy_config_aneg);
@@ -1563,6 +1605,21 @@ static void of_set_phy_supported(struct phy_device *phydev) __set_phy_supported(phydev, max_speed); } +static void of_set_phy_eee_broken(struct phy_device *phydev) +{ + struct device_node *node = phydev->mdio.dev.of_node; + u32 broken; + + if (!IS_ENABLED(CONFIG_OF_MDIO)) + return; + + if (!node) + return; + + if (!of_property_read_u32(node, "eee-broken-modes", &broken)) + phydev->eee_broken_modes = broken; +} + /** * phy_probe - probe and init a PHY device * @dev: device to probe and init
@@ -1600,6 +1657,11 @@ static int phy_probe(struct device *dev) of_set_phy_supported(phydev); phydev->advertising = phydev->supported; + /* Get the EEE modes we want to prohibit. We will ask + * the PHY stop advertising these mode later on + */ + of_set_phy_eee_broken(phydev); + /* Set the state to READY by default */ phydev->state = PHY_READY;
diff --git a/include/linux/phy.h b/include/linux/phy.h
index edde28ce163a..b53177fd38af 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h@@ -417,6 +417,9 @@ struct phy_device { u32 advertising; u32 lp_advertising; + /* Energy efficient ethernet modes which should be prohibited */ + u32 eee_broken_modes; + int autoneg; int link_timeout;
--
2.7.4