| Message ID | 20221221080144.2549125-2-xiaoning.wang@nxp.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | fix mac not working after system resumed with WoL enabled | expand |
On Wed, Dec 21, 2022 at 04:01:43PM +0800, Clark Wang wrote: > Issue we met: > On some platforms, mac cannot work after resumed from the suspend with WoL > enabled. > > The cause of the issue: > 1. phylink_resolve() is in a workqueue which will not be executed immediately. > This is the call sequence: > phylink_resolve()->phylink_link_up()->pl->mac_ops->mac_link_up() > For stmmac driver, mac_link_up() will set the correct speed/duplex... > values which are from link_state. > 2. In stmmac_resume(), it will call stmmac_hw_setup() after called the > phylink_resume(), because mac need phy rx_clk to do the reset. > stmmac_core_init() is called in function stmmac_hw_setup(), which will > reset the mac and set the speed/duplex... to default value. > Conclusion: Because phylink_resolve() cannot determine when it is called, it > cannot be guaranteed to be called after stmmac_core_init(). > Once stmmac_core_init() is called after phylink_resolve(), > the mac will be misconfigured and cannot be used. > > In order to avoid this problem, add a function called phylink_phy_resume() > to resume phy separately. This eliminates the need to call phylink_resume() > before stmmac_hw_setup(). > > Add another judgement before called phy_start() in phylink_start(). This way > phy_start() will not be called multiple times when resumes. At the same time, > it may not affect other drivers that do not use phylink_phy_resume(). > It'd be nice to see Fixes tag. > Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> > --- > drivers/net/phy/phylink.c | 21 ++++++++++++++++++++- > include/linux/phylink.h | 1 + > 2 files changed, 21 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c > index 09cc65c0da93..5bab59142579 100644 > --- a/drivers/net/phy/phylink.c > +++ b/drivers/net/phy/phylink.c > @@ -1939,7 +1939,7 @@ void phylink_start(struct phylink *pl) > } > if (poll) > mod_timer(&pl->link_poll, jiffies + HZ); > - if (pl->phydev) > + if (pl->phydev && pl->phydev->state < PHY_UP) > phy_start(pl->phydev); > if (pl->sfp_bus) > sfp_upstream_start(pl->sfp_bus); > @@ -2020,6 +2020,25 @@ void phylink_suspend(struct phylink *pl, bool mac_wol) > } > EXPORT_SYMBOL_GPL(phylink_suspend); > > +/** > + * phylink_phy_resume() - resume phy alone > + * @pl: a pointer to a &struct phylink returned from phylink_create() > + * > + * In the MAC driver using phylink, if the MAC needs the clock of the phy > + * when it resumes, can call this function to resume the phy separately. > + * Then proceed to MAC resume operations. > + */ > +void phylink_phy_resume(struct phylink *pl) > +{ > + ASSERT_RTNL(); > + > + if (!test_bit(PHYLINK_DISABLE_MAC_WOL, &pl->phylink_disable_state) > + && pl->phydev) you can fit && at the end of the previous line. > + phy_start(pl->phydev); > + this blank line is not necessary. > +} > +EXPORT_SYMBOL_GPL(phylink_phy_resume); > + > /** > * phylink_resume() - handle a network device resume event > * @pl: a pointer to a &struct phylink returned from phylink_create() > diff --git a/include/linux/phylink.h b/include/linux/phylink.h > index c492c26202b5..6edfab5f754c 100644 > --- a/include/linux/phylink.h > +++ b/include/linux/phylink.h > @@ -589,6 +589,7 @@ void phylink_stop(struct phylink *); > > void phylink_suspend(struct phylink *pl, bool mac_wol); > void phylink_resume(struct phylink *pl); > +void phylink_phy_resume(struct phylink *pl); > > void phylink_ethtool_get_wol(struct phylink *, struct ethtool_wolinfo *); > int phylink_ethtool_set_wol(struct phylink *, struct ethtool_wolinfo *); > -- > 2.34.1 >
On Wed, Dec 21, 2022 at 04:01:43PM +0800, Clark Wang wrote: > Issue we met: > On some platforms, mac cannot work after resumed from the suspend with WoL > enabled. > > The cause of the issue: > 1. phylink_resolve() is in a workqueue which will not be executed immediately. > This is the call sequence: > phylink_resolve()->phylink_link_up()->pl->mac_ops->mac_link_up() > For stmmac driver, mac_link_up() will set the correct speed/duplex... > values which are from link_state. > 2. In stmmac_resume(), it will call stmmac_hw_setup() after called the > phylink_resume(), because mac need phy rx_clk to do the reset. > stmmac_core_init() is called in function stmmac_hw_setup(), which will > reset the mac and set the speed/duplex... to default value. > Conclusion: Because phylink_resolve() cannot determine when it is called, it > cannot be guaranteed to be called after stmmac_core_init(). > Once stmmac_core_init() is called after phylink_resolve(), > the mac will be misconfigured and cannot be used. > > In order to avoid this problem, add a function called phylink_phy_resume() > to resume phy separately. This eliminates the need to call phylink_resume() > before stmmac_hw_setup(). > > Add another judgement before called phy_start() in phylink_start(). This way > phy_start() will not be called multiple times when resumes. At the same time, > it may not affect other drivers that do not use phylink_phy_resume(). > > Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> > --- > drivers/net/phy/phylink.c | 21 ++++++++++++++++++++- > include/linux/phylink.h | 1 + > 2 files changed, 21 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c > index 09cc65c0da93..5bab59142579 100644 > --- a/drivers/net/phy/phylink.c > +++ b/drivers/net/phy/phylink.c > @@ -1939,7 +1939,7 @@ void phylink_start(struct phylink *pl) > } > if (poll) > mod_timer(&pl->link_poll, jiffies + HZ); > - if (pl->phydev) > + if (pl->phydev && pl->phydev->state < PHY_UP) I'm really not happy with this - not only does this subvert the checks in phy_start(), it's a layering violation, and it delves into internals of phylib in an unprotected way.
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 09cc65c0da93..5bab59142579 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -1939,7 +1939,7 @@ void phylink_start(struct phylink *pl) } if (poll) mod_timer(&pl->link_poll, jiffies + HZ); - if (pl->phydev) + if (pl->phydev && pl->phydev->state < PHY_UP) phy_start(pl->phydev); if (pl->sfp_bus) sfp_upstream_start(pl->sfp_bus); @@ -2020,6 +2020,25 @@ void phylink_suspend(struct phylink *pl, bool mac_wol) } EXPORT_SYMBOL_GPL(phylink_suspend); +/** + * phylink_phy_resume() - resume phy alone + * @pl: a pointer to a &struct phylink returned from phylink_create() + * + * In the MAC driver using phylink, if the MAC needs the clock of the phy + * when it resumes, can call this function to resume the phy separately. + * Then proceed to MAC resume operations. + */ +void phylink_phy_resume(struct phylink *pl) +{ + ASSERT_RTNL(); + + if (!test_bit(PHYLINK_DISABLE_MAC_WOL, &pl->phylink_disable_state) + && pl->phydev) + phy_start(pl->phydev); + +} +EXPORT_SYMBOL_GPL(phylink_phy_resume); + /** * phylink_resume() - handle a network device resume event * @pl: a pointer to a &struct phylink returned from phylink_create() diff --git a/include/linux/phylink.h b/include/linux/phylink.h index c492c26202b5..6edfab5f754c 100644 --- a/include/linux/phylink.h +++ b/include/linux/phylink.h @@ -589,6 +589,7 @@ void phylink_stop(struct phylink *); void phylink_suspend(struct phylink *pl, bool mac_wol); void phylink_resume(struct phylink *pl); +void phylink_phy_resume(struct phylink *pl); void phylink_ethtool_get_wol(struct phylink *, struct ethtool_wolinfo *); int phylink_ethtool_set_wol(struct phylink *, struct ethtool_wolinfo *);
Issue we met: On some platforms, mac cannot work after resumed from the suspend with WoL enabled. The cause of the issue: 1. phylink_resolve() is in a workqueue which will not be executed immediately. This is the call sequence: phylink_resolve()->phylink_link_up()->pl->mac_ops->mac_link_up() For stmmac driver, mac_link_up() will set the correct speed/duplex... values which are from link_state. 2. In stmmac_resume(), it will call stmmac_hw_setup() after called the phylink_resume(), because mac need phy rx_clk to do the reset. stmmac_core_init() is called in function stmmac_hw_setup(), which will reset the mac and set the speed/duplex... to default value. Conclusion: Because phylink_resolve() cannot determine when it is called, it cannot be guaranteed to be called after stmmac_core_init(). Once stmmac_core_init() is called after phylink_resolve(), the mac will be misconfigured and cannot be used. In order to avoid this problem, add a function called phylink_phy_resume() to resume phy separately. This eliminates the need to call phylink_resume() before stmmac_hw_setup(). Add another judgement before called phy_start() in phylink_start(). This way phy_start() will not be called multiple times when resumes. At the same time, it may not affect other drivers that do not use phylink_phy_resume(). Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> --- drivers/net/phy/phylink.c | 21 ++++++++++++++++++++- include/linux/phylink.h | 1 + 2 files changed, 21 insertions(+), 1 deletion(-)