From d853d145ea3e63387a2ac759aa41d5e43876e561 Mon Sep 17 00:00:00 2001 From: jbrunet Date: Mon, 28 Nov 2016 10:46:46 +0100 Subject: [PATCH] net: phy: add an option to disable EEE advertisement MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Tested-by: Yegor Yefremov Tested-by: Andreas Färber Signed-off-by: David S. Miller --- 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 @@ -1120,6 +1120,43 @@ static int genphy_config_advert(struct phy_device *phydev) return changed; } +/** + * 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;