| Message ID | 20230324081656.2969663-2-michael.wei.hong.sit@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Fix PHY handle no longer parsing | expand |
On Fri, 24 Mar 2023 16:16:54 +0800 Michael Sit Wei Hong wrote: > Provide phylink_expects_phy() to allow MAC drivers to check if it > is expecting a PHY to attach to. Since fixed-linked setups do not > need to attach to a PHY. > > Provides a boolean value as to if the MAC should expect a PHY. > returns true if a PHY is expected. > > Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com> Russell, looks good? > diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c > index 1a2f074685fa..5c2bd1370993 100644 > --- a/drivers/net/phy/phylink.c > +++ b/drivers/net/phy/phylink.c > @@ -1586,6 +1586,19 @@ void phylink_destroy(struct phylink *pl) > } > EXPORT_SYMBOL_GPL(phylink_destroy); > > +/** > + * phylink_expects_phy() - Determine if phylink expects a phy to be attached > + * @pl: a pointer to a &struct phylink returned from phylink_create() > + * > + * Fixed-link mode does not need a PHY, returns a boolean value to check if > + * phylink will be expecting a PHY to attach. > + */ > +bool phylink_expects_phy(struct phylink *pl) > +{ > + return pl->cfg_link_an_mode != MLO_AN_FIXED; > +} > +EXPORT_SYMBOL_GPL(phylink_expects_phy); > + > static void phylink_phy_change(struct phy_device *phydev, bool up) > { > struct phylink *pl = phydev->phylink; > diff --git a/include/linux/phylink.h b/include/linux/phylink.h > index c492c26202b5..637698ed5cb6 100644 > --- a/include/linux/phylink.h > +++ b/include/linux/phylink.h > @@ -574,6 +574,7 @@ struct phylink *phylink_create(struct phylink_config *, struct fwnode_handle *, > phy_interface_t iface, > const struct phylink_mac_ops *mac_ops); > void phylink_destroy(struct phylink *); > +bool phylink_expects_phy(struct phylink *pl); > > int phylink_connect_phy(struct phylink *, struct phy_device *); > int phylink_of_phy_connect(struct phylink *, struct device_node *, u32 flags);
On Tue, Mar 28, 2023 at 06:57:20PM -0700, Jakub Kicinski wrote: > On Fri, 24 Mar 2023 16:16:54 +0800 Michael Sit Wei Hong wrote: > > Provide phylink_expects_phy() to allow MAC drivers to check if it > > is expecting a PHY to attach to. Since fixed-linked setups do not > > need to attach to a PHY. > > > > Provides a boolean value as to if the MAC should expect a PHY. > > returns true if a PHY is expected. > > > > Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com> > > Russell, looks good? Not really, given that phylink_attach_phy() will refuse to attach a PHY when: if (WARN_ON(pl->cfg_link_an_mode == MLO_AN_FIXED || (pl->cfg_link_an_mode == MLO_AN_INBAND && phy_interface_mode_is_8023z(interface) && !pl->sfp_bus))) return -EINVAL; So, if we introduce a helper named "phylink_expects_phy" that returns true when cfg_link_an_mode == MLO_AN_INBAND and the interface mode is e.g. 1000base-X, but then someone tries to attach a PHY, the kernel spits out a warning, backtrace, and a return value of -EINVAL, things are going to look really rather stupid.
> -----Original Message----- > From: Russell King <linux@armlinux.org.uk> > Sent: Wednesday, March 29, 2023 5:01 PM > To: Jakub Kicinski <kuba@kernel.org> > Cc: Sit, Michael Wei Hong <michael.wei.hong.sit@intel.com>; > Giuseppe Cavallaro <peppe.cavallaro@st.com>; Alexandre Torgue > <alexandre.torgue@foss.st.com>; Jose Abreu > <joabreu@synopsys.com>; David S . Miller <davem@davemloft.net>; > Eric Dumazet <edumazet@google.com>; Paolo Abeni > <pabeni@redhat.com>; Maxime Coquelin > <mcoquelin.stm32@gmail.com>; Ong, Boon Leong > <boon.leong.ong@intel.com>; netdev@vger.kernel.org; linux- > stm32@st-md-mailman.stormreply.com; linux-arm- > kernel@lists.infradead.org; linux-kernel@vger.kernel.org; Looi, > Hong Aun <hong.aun.looi@intel.com>; Voon, Weifeng > <weifeng.voon@intel.com>; Lai, Peter Jun Ann > <peter.jun.ann.lai@intel.com> > Subject: Re: [PATCH net v3 1/3] net: phylink: add > phylink_expects_phy() method > > On Tue, Mar 28, 2023 at 06:57:20PM -0700, Jakub Kicinski wrote: > > On Fri, 24 Mar 2023 16:16:54 +0800 Michael Sit Wei Hong wrote: > > > Provide phylink_expects_phy() to allow MAC drivers to check if it > is > > > expecting a PHY to attach to. Since fixed-linked setups do not > need > > > to attach to a PHY. > > > > > > Provides a boolean value as to if the MAC should expect a PHY. > > > returns true if a PHY is expected. > > > > > > Signed-off-by: Michael Sit Wei Hong > <michael.wei.hong.sit@intel.com> > > > > Russell, looks good? > > Not really, given that phylink_attach_phy() will refuse to attach a > PHY > when: > > if (WARN_ON(pl->cfg_link_an_mode == MLO_AN_FIXED || > (pl->cfg_link_an_mode == MLO_AN_INBAND && > phy_interface_mode_is_8023z(interface) && !pl- > >sfp_bus))) > return -EINVAL; > > So, if we introduce a helper named "phylink_expects_phy" that > returns true when cfg_link_an_mode == MLO_AN_INBAND and the > interface mode is e.g. 1000base-X, but then someone tries to attach > a PHY, the kernel spits out a warning, backtrace, and a return value > of -EINVAL, things are going to look really rather stupid. > Should we check for these 3 conditions as well then? (pl->cfg_link_an_mode == MLO_AN_INBAND && phy_interface_mode_is_8023z(interface) && !pl->sfp_bus) to determine if phylink expects a phy. > -- > RMK's Patch system: > https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
On Wed, Mar 29, 2023 at 09:34:05AM +0000, Sit, Michael Wei Hong wrote: > > > > -----Original Message----- > > From: Russell King <linux@armlinux.org.uk> > > Sent: Wednesday, March 29, 2023 5:01 PM > > To: Jakub Kicinski <kuba@kernel.org> > > Cc: Sit, Michael Wei Hong <michael.wei.hong.sit@intel.com>; > > Giuseppe Cavallaro <peppe.cavallaro@st.com>; Alexandre Torgue > > <alexandre.torgue@foss.st.com>; Jose Abreu > > <joabreu@synopsys.com>; David S . Miller <davem@davemloft.net>; > > Eric Dumazet <edumazet@google.com>; Paolo Abeni > > <pabeni@redhat.com>; Maxime Coquelin > > <mcoquelin.stm32@gmail.com>; Ong, Boon Leong > > <boon.leong.ong@intel.com>; netdev@vger.kernel.org; linux- > > stm32@st-md-mailman.stormreply.com; linux-arm- > > kernel@lists.infradead.org; linux-kernel@vger.kernel.org; Looi, > > Hong Aun <hong.aun.looi@intel.com>; Voon, Weifeng > > <weifeng.voon@intel.com>; Lai, Peter Jun Ann > > <peter.jun.ann.lai@intel.com> > > Subject: Re: [PATCH net v3 1/3] net: phylink: add > > phylink_expects_phy() method > > > > On Tue, Mar 28, 2023 at 06:57:20PM -0700, Jakub Kicinski wrote: > > > On Fri, 24 Mar 2023 16:16:54 +0800 Michael Sit Wei Hong wrote: > > > > Provide phylink_expects_phy() to allow MAC drivers to check if it > > is > > > > expecting a PHY to attach to. Since fixed-linked setups do not > > need > > > > to attach to a PHY. > > > > > > > > Provides a boolean value as to if the MAC should expect a PHY. > > > > returns true if a PHY is expected. > > > > > > > > Signed-off-by: Michael Sit Wei Hong > > <michael.wei.hong.sit@intel.com> > > > > > > Russell, looks good? > > > > Not really, given that phylink_attach_phy() will refuse to attach a > > PHY > > when: > > > > if (WARN_ON(pl->cfg_link_an_mode == MLO_AN_FIXED || > > (pl->cfg_link_an_mode == MLO_AN_INBAND && > > phy_interface_mode_is_8023z(interface) && !pl- > > >sfp_bus))) > > return -EINVAL; > > > > So, if we introduce a helper named "phylink_expects_phy" that > > returns true when cfg_link_an_mode == MLO_AN_INBAND and the > > interface mode is e.g. 1000base-X, but then someone tries to attach > > a PHY, the kernel spits out a warning, backtrace, and a return value > > of -EINVAL, things are going to look really rather stupid. > > > Should we check for these 3 conditions as well then? > (pl->cfg_link_an_mode == MLO_AN_INBAND && > phy_interface_mode_is_8023z(interface) && !pl->sfp_bus) > to determine if phylink expects a phy. If there's a sfp bus, then we don't expect a PHY from the MAC driver (as there can only be one PHY attached), and as phylink_expects_phy() is for the MAC driver to use, we should be returning false if pl->sfp_bus != NULL. pl->cfg_link_an_mode == MLO_AN_FIXED || (pl->cfg_link_an_mode == MLO_AN_INBAND && phy_interface_mode_is_8023z(interface)) Is true when we're in fixed-link mode, or if we're in in-band mode and using 1000base-X or 25000base-X. These are the conditions that we don't expect the MAC driver to give us a PHY. To put that in positive logic, we expect a PHY from the MAC when we're in PHY mode, or when we're in in-band mode and using SGMII, QSGMII, USXGMII, RGMII, etc. The reason for the extra "&& !pl->sfp_bus" in phylink_attach_phy() is to allow SFPs to connect to the MAC using inband mode with 1000base-X and 2500base-X interface modes. These are not for the MAC-side of things though.
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c index 1a2f074685fa..5c2bd1370993 100644 --- a/drivers/net/phy/phylink.c +++ b/drivers/net/phy/phylink.c @@ -1586,6 +1586,19 @@ void phylink_destroy(struct phylink *pl) } EXPORT_SYMBOL_GPL(phylink_destroy); +/** + * phylink_expects_phy() - Determine if phylink expects a phy to be attached + * @pl: a pointer to a &struct phylink returned from phylink_create() + * + * Fixed-link mode does not need a PHY, returns a boolean value to check if + * phylink will be expecting a PHY to attach. + */ +bool phylink_expects_phy(struct phylink *pl) +{ + return pl->cfg_link_an_mode != MLO_AN_FIXED; +} +EXPORT_SYMBOL_GPL(phylink_expects_phy); + static void phylink_phy_change(struct phy_device *phydev, bool up) { struct phylink *pl = phydev->phylink; diff --git a/include/linux/phylink.h b/include/linux/phylink.h index c492c26202b5..637698ed5cb6 100644 --- a/include/linux/phylink.h +++ b/include/linux/phylink.h @@ -574,6 +574,7 @@ struct phylink *phylink_create(struct phylink_config *, struct fwnode_handle *, phy_interface_t iface, const struct phylink_mac_ops *mac_ops); void phylink_destroy(struct phylink *); +bool phylink_expects_phy(struct phylink *pl); int phylink_connect_phy(struct phylink *, struct phy_device *); int phylink_of_phy_connect(struct phylink *, struct device_node *, u32 flags);
Provide phylink_expects_phy() to allow MAC drivers to check if it is expecting a PHY to attach to. Since fixed-linked setups do not need to attach to a PHY. Provides a boolean value as to if the MAC should expect a PHY. returns true if a PHY is expected. Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com> --- drivers/net/phy/phylink.c | 13 +++++++++++++ include/linux/phylink.h | 1 + 2 files changed, 14 insertions(+)