Messages in this thread | | | Subject | Re: [RFC PATCH net] net: phy: Fix "link partner" information disappear issue | From | Yonglong Liu <> | Date | Fri, 11 Oct 2019 13:55:30 +0800 |
| |
On 2019/10/11 3:17, Heiner Kallweit wrote: > On 10.10.2019 11:30, Yonglong Liu wrote: >> Some drivers just call phy_ethtool_ksettings_set() to set the >> links, for those phy drivers that use genphy_read_status(), if >> autoneg is on, and the link is up, than execute "ethtool -s >> ethx autoneg on" will cause "link partner" information disappear. >> >> The call trace is phy_ethtool_ksettings_set()->phy_start_aneg() >> ->linkmode_zero(phydev->lp_advertising)->genphy_read_status(), >> the link didn't change, so genphy_read_status() just return, and >> phydev->lp_advertising is zero now. >> > I think that clearing link partner advertising info in > phy_start_aneg() is questionable. If advertising doesn't change > then phy_config_aneg() basically is a no-op. Instead we may have > to clear the link partner advertising info in genphy_read_lpa() > if aneg is disabled or aneg isn't completed (basically the same > as in genphy_c45_read_lpa()). Something like: > > if (!phydev->autoneg_complete) { /* also covers case that aneg is disabled */ > linkmode_zero(phydev->lp_advertising); > } else if (phydev->autoneg == AUTONEG_ENABLE) { > ... > } >
If clear the link partner advertising info in genphy_read_lpa() and genphy_c45_read_lpa(), for the drivers that use genphy_read_status() is ok, but for those drivers that use there own read_status() may have problem, like aqr_read_status(), it will update lp_advertising first, and than call genphy_c45_read_status(), so will cause lp_advertising lost.
Another question, please see genphy_c45_read_status(), if clear the link partner advertising info in genphy_c45_read_lpa(), if autoneg is off, phydev->lp_advertising will not clear.
>> This patch call genphy_read_lpa() before the link state judgement >> to fix this problem. >> >> Fixes: 88d6272acaaa ("net: phy: avoid unneeded MDIO reads in genphy_read_status") >> Signed-off-by: Yonglong Liu <liuyonglong@huawei.com> >> --- >> drivers/net/phy/phy_device.c | 8 ++++---- >> 1 file changed, 4 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c >> index 9d2bbb1..ef3073c 100644 >> --- a/drivers/net/phy/phy_device.c >> +++ b/drivers/net/phy/phy_device.c >> @@ -1839,6 +1839,10 @@ int genphy_read_status(struct phy_device *phydev) >> if (err) >> return err; >> >> + err = genphy_read_lpa(phydev); >> + if (err < 0) >> + return err; >> + >> /* why bother the PHY if nothing can have changed */ >> if (phydev->autoneg == AUTONEG_ENABLE && old_link && phydev->link) >> return 0; >> @@ -1848,10 +1852,6 @@ int genphy_read_status(struct phy_device *phydev) >> phydev->pause = 0; >> phydev->asym_pause = 0; >> >> - err = genphy_read_lpa(phydev); >> - if (err < 0) >> - return err; >> - >> if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete) { >> phy_resolve_aneg_linkmode(phydev); >> } else if (phydev->autoneg == AUTONEG_DISABLE) { >> > > > . >
| |