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2025-09-05net: phy: transfer phy_config_inband() locking responsibility to phylinkdavem/netVladimir Oltean1-0/+9
Problem description =================== Lockdep reports a possible circular locking dependency (AB/BA) between &pl->state_mutex and &phy->lock, as follows. phylink_resolve() // acquires &pl->state_mutex -> phylink_major_config() -> phy_config_inband() // acquires &pl->phydev->lock whereas all the other call sites where &pl->state_mutex and &pl->phydev->lock have the locking scheme reversed. Everywhere else, &pl->phydev->lock is acquired at the top level, and &pl->state_mutex at the lower level. A clear example is phylink_bringup_phy(). The outlier is the newly introduced phy_config_inband() and the existing lock order is the correct one. To understand why it cannot be the other way around, it is sufficient to consider phylink_phy_change(), phylink's callback from the PHY device's phy->phy_link_change() virtual method, invoked by the PHY state machine. phy_link_up() and phy_link_down(), the (indirect) callers of phylink_phy_change(), are called with &phydev->lock acquired. Then phylink_phy_change() acquires its own &pl->state_mutex, to serialize changes made to its pl->phy_state and pl->link_config. So all other instances of &pl->state_mutex and &phydev->lock must be consistent with this order. Problem impact ============== I think the kernel runs a serious deadlock risk if an existing phylink_resolve() thread, which results in a phy_config_inband() call, is concurrent with a phy_link_up() or phy_link_down() call, which will deadlock on &pl->state_mutex in phylink_phy_change(). Practically speaking, the impact may be limited by the slow speed of the medium auto-negotiation protocol, which makes it unlikely for the current state to still be unresolved when a new one is detected, but I think the problem is there. Nonetheless, the problem was discovered using lockdep. Proposed solution ================= Practically speaking, the phy_config_inband() requirement of having phydev->lock acquired must transfer to the caller (phylink is the only caller). There, it must bubble up until immediately before &pl->state_mutex is acquired, for the cases where that takes place. Solution details, considerations, notes ======================================= This is the phy_config_inband() call graph: sfp_upstream_ops :: connect_phy() | v phylink_sfp_connect_phy() | v phylink_sfp_config_phy() | | sfp_upstream_ops :: module_insert() | | | v | phylink_sfp_module_insert() | | | | sfp_upstream_ops :: module_start() | | | | | v | | phylink_sfp_module_start() | | | | v v | phylink_sfp_config_optical() phylink_start() | | | phylink_resume() v v | | phylink_sfp_set_config() | | | v v v phylink_mac_initial_config() | phylink_resolve() | | phylink_ethtool_ksettings_set() v v v phylink_major_config() | v phy_config_inband() phylink_major_config() caller #1, phylink_mac_initial_config(), does not acquire &pl->state_mutex nor do its callers. It must acquire &pl->phydev->lock prior to calling phylink_major_config(). phylink_major_config() caller #2, phylink_resolve() acquires &pl->state_mutex, thus also needs to acquire &pl->phydev->lock. phylink_major_config() caller #3, phylink_ethtool_ksettings_set(), is completely uninteresting, because it only calls phylink_major_config() if pl->phydev is NULL (otherwise it calls phy_ethtool_ksettings_set()). We need to change nothing there. Other solutions =============== The lock inversion between &pl->state_mutex and &pl->phydev->lock has occurred at least once before, as seen in commit c718af2d00a3 ("net: phylink: fix ethtool -A with attached PHYs"). The solution there was to simply not call phy_set_asym_pause() under the &pl->state_mutex. That cannot be extended to our case though, where the phy_config_inband() call is much deeper inside the &pl->state_mutex section. Fixes: 5fd0f1a02e75 ("net: phylink: add negotiation of in-band capabilities") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/20250904125238.193990-2-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-05net: phylink: add lock for serializing concurrent pl->phydev writes with resolverVladimir Oltean1-3/+16
Currently phylink_resolve() protects itself against concurrent phylink_bringup_phy() or phylink_disconnect_phy() calls which modify pl->phydev by relying on pl->state_mutex. The problem is that in phylink_resolve(), pl->state_mutex is in a lock inversion state with pl->phydev->lock. So pl->phydev->lock needs to be acquired prior to pl->state_mutex. But that requires dereferencing pl->phydev in the first place, and without pl->state_mutex, that is racy. Hence the reason for the extra lock. Currently it is redundant, but it will serve a functional purpose once mutex_lock(&phy->lock) will be moved outside of the mutex_lock(&pl->state_mutex) section. Another alternative considered would have been to let phylink_resolve() acquire the rtnl_mutex, which is also held when phylink_bringup_phy() and phylink_disconnect_phy() are called. But since phylink_disconnect_phy() runs under rtnl_lock(), it would deadlock with phylink_resolve() when calling flush_work(&pl->resolve). Additionally, it would have been undesirable because it would have unnecessarily blocked many other call paths as well in the entire kernel, so the smaller-scoped lock was preferred. Link: https://lore.kernel.org/netdev/aLb6puGVzR29GpPx@shell.armlinux.org.uk/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/20250904125238.193990-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-03net: phylink: move PHY interrupt request to non-fail pathRussell King (Oracle)1-3/+3
The blamed commit added code which could return an error after we requested the PHY interrupt. When we return an error, the caller will call phy_detach() which fails to free the interrupt. Rearrange the code such that failing operations happen before the interrupt is requested, thereby allowing phy_detach() to be used. Note that replacing phy_detach() with phy_disconnect() in these paths could lead to freeing an interrupt which was never requested. Fixes: 1942b1c6f687 ("net: phylink: make configuring clock-stop dependent on MAC support") Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://patch.msgid.link/E1ut35k-00000001UEl-0iq6@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-02net: phylink: disable autoneg for interfaces that have no inbandRussell King (Oracle)1-0/+18
Mathew reports that as a result of commit 6561f0e547be ("net: pcs: pcs-lynx: implement pcs_inband_caps() method"), 10G SFP modules no longer work with the Lynx PCS. This problem is not specific to the Lynx PCS, but is caused by commit df874f9e52c3 ("net: phylink: add pcs_inband_caps() method") which added validation of the autoneg state to the optical SFP configuration path. Fix this by handling interface modes that fundamentally have no inband negotiation more correctly - if we only have a single interface mode, clear the Autoneg support bit and the advertising mask. If the module can operate with several different interface modes, autoneg may be supported for other modes, so leave the support mask alone and just clear the Autoneg bit in the advertising mask. This restores 10G optical module functionality with PCS that supply their inband support, and makes ethtool output look sane. Reported-by: Mathew McBride <matt@traverse.com.au> Closes: https://lore.kernel.org/r/025c0ebe-5537-4fa3-b05a-8b835e5ad317@app.fastmail.com Fixes: df874f9e52c3 ("net: phylink: add pcs_inband_caps() method") Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/E1uslwx-00000001SPB-2kiM@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-02net: phylink: provide phylink_get_inband_type()Russell King (Oracle)1-35/+44
Provide a function to get the type of the inband signalling used for a PHY interface type. This will be used in the subsequent patch to address problems with 10G optical modules. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://patch.msgid.link/E1uslws-00000001SP5-1R2R@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-09net: phy: MII-Lite PHY interface modeKamil Horák - 2N1-0/+1
Some Broadcom PHYs are capable to operate in simplified MII mode, without TXER, RXER, CRS and COL signals as defined for the MII. The MII-Lite mode can be used on most Ethernet controllers with full MII interface by just leaving the input signals (RXER, CRS, COL) inactive. The absence of COL signal makes half-duplex link modes impossible but does not interfere with BroadR-Reach link modes on Broadcom PHYs, because they are all full-duplex only. Add MII-Lite interface mode, especially for Broadcom two-wire PHYs. Signed-off-by: Kamil Horák - 2N <kamilh@axis.com> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/20250708090140.61355-2-kamilh@axis.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07net: phylink: add phylink_sfp_select_interface_speed()Russell King (Oracle)1-1/+40
Add phylink_sfp_select_interface_speed() which attempts to select the SFP interface based on the ethtool speed when autoneg is turned off. This allows users to turn off autoneg for SFPs that support multiple interface modes, and have an appropriate interface mode selected. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1uWu14-005KXo-IO@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07net: phylink: clear SFP interfaces when not in useRussell King (Oracle)1-0/+10
Clear the SFP interfaces bitmap when we're not using it - in other words, when a module is unplugged, or we're using a PHY on the module. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1uWu0z-005KXi-EM@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07net: phylink: restrict SFP interfaces to those that are supportedRussell King (Oracle)1-5/+4
When configuring an optical SFP interface, restrict the bitmap of SFP interfaces (pl->sfp_interfaces) to those that are supported by the host, rather than calculating this in a local variable. This will allow us to avoid recomputing this in the phylink_ethtool_ksettings_set() path. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1uWu0u-005KXc-A4@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-24net: phy: Add interface types for 50G and 100GAlexander Duyck1-0/+13
Add support for 802.3cd based interface types 50GBASE-R and 100GBASE-P. This choice in naming is based on section 135 of the 802.3-2022 IEEE Standard. In addition it is adding support for what I am referring to as LAUI which is based on annex 135C of the IEEE Standard, and shares many similarities with the 25/50G consortium. The main difference between the two is that IEEE spec refers to LAUI as the AUI before the RS(544/514) FEC, whereas the 25/50G use this lane and frequency combination after going through RS(528/514), Base-R or no FEC at all. Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Link: https://patch.msgid.link/175028444205.625704.4191700324472974116.stgit@ahduyck-xeon-server.home.arpa Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-04-29net: phylink: Drop unused defines for SUPPORTED/ADVERTISED_INTERFACESAlexander Duyck1-7/+0
The defines for SUPPORTED_INTERFACES and ADVERTISED_INTERFACES both appear to be unused. I couldn't find anything that actually references them in the original diff that added them and it seems like they have persisted despite using deprecated defines that aren't supposed to be used as per the ethtool.h header that defines the bits they are composed of. Since they are unused, and not supposed to be used anymore I am just dropping the lines of code since they seem to just be occupying space. Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/174578398922.1580647.9720643128205980455.stgit@ahduyck-xeon-server.home.arpa Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-22net: phylink: fix suspend/resume with WoL enabled and link downRussell King (Oracle)1-16/+22
When WoL is enabled, we update the software state in phylink to indicate that the link is down, and disable the resolver from bringing the link back up. On resume, we attempt to bring the overall state into consistency by calling the .mac_link_down() method, but this is wrong if the link was already down, as phylink strictly orders the .mac_link_up() and .mac_link_down() methods - and this would break that ordering. Fixes: f97493657c63 ("net: phylink: add suspend/resume support") Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Tested-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1u55Qf-0016RN-PA@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-05treewide: Switch/rename to timer_delete[_sync]()Thomas Gleixner1-2/+2
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-25net: phylink: force link down on major_config failureRussell King (Oracle)1-8/+34
If we fail to configure the MAC or PCS according to the desired mode, do not allow the network link to come up until we have successfully configured the MAC and PCS. This improves phylink's behaviour when an error occurs. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1twkqO-0006FI-Gm@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25net: phylink: add functions to block/unblock rx clock stopRussell King (Oracle)1-0/+59
Some MACs require the PHY receive clock to be running to complete setup actions. This may fail if the PHY has negotiated EEE, the MAC supports receive clock stop, and the link has entered LPI state. Provide a pair of APIs that MAC drivers can use to temporarily block the PHY disabling the receive clock. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tvO6k-008Vjt-MZ@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-25net: phylink: add phylink_prepare_resume()Russell King (Oracle)1-0/+25
When the system is suspended, the PHY may be placed in low-power mode by setting the BMCR 0.11 Power down bit. IEEE 802.3 states that the behaviour of the PHY in this state is implementation specific, and the PHY is not required to meet the RX_CLK and TX_CLK requirements. Essentially, this means that a PHY may stop the clocks that it is generating while in power down state. However, MACs exist which require the clocks from the PHY to be running in order to properly resume. phylink_prepare_resume() provides them with a way to clear the Power down bit early. Note, however, that IEEE 802.3 gives PHYs up to 500ms grace before the transmit and receive clocks meet the requirements after clearing the power down bit. Add a resume preparation function, which will ensure that the receive clock from the PHY is appropriately configured while resuming. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tvO6V-008Vjb-AP@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-24net: phylink: Remove unused function pointer from phylink structureAlexander Duyck1-2/+0
From what I can tell the .get_fixed_state pointer in the phylink structure hasn't been used since commit 5c05c1dbb177 ("net: phylink, dsa: eliminate phylink_fixed_state_cb()") . Since I can't find any users for it we might as well just drop the pointer. Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/174240634772.1745174.5690351737682751849.stgit@ahduyck-xeon-server.home.arpa Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-18net: phylink: Use phy_caps to get an interface's capabilities and modesMaxime Chevallier1-76/+14
Phylink has internal code to get the MAC capabilities of a given PHY interface (what are the supported speed and duplex). Extract that into phy_caps, but use the link_capa for conversion. Add an internal phylink helper for the link caps -> mac caps conversion, and use this in phylink_caps_to_linkmodes(). Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20250307173611.129125-14-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-18net: phylink: Convert capabilities to linkmodes using phy_capsMaxime Chevallier1-134/+21
phylink_caps_to_linkmodes() is used to derive a list of linkmodes that can be conceivably exposed using a given set of speeds and duplex through phylink's MAC capabilities. This list can be derived from the link_caps array in phy_caps, provided we convert the MAC capabilities into a LINK_CAPA bitmask first. Introduce an internal phylink helper phylink_caps_to_link_caps() to convert from MAC capabilities into phy_caps, then phy_caps_linkmodes() to do the link_caps -> linkmodes conversion. This avoids having to update phylink for every new linkmode. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20250307173611.129125-13-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-18net: phylink: Add a mapping between MAC_CAPS and LINK_CAPSMaxime Chevallier1-24/+25
phylink allows MAC drivers to report the capabilities in terms of speed, duplex and pause support. This is done through a dedicated set of enum values in the form of the MAC_ capabilities. They are very close to what the LINK_CAPA_xxx can express, with the difference that LINK_CAPA don't have any information about Pause/Asym Pause support. To prepare converting phylink to using the phy_caps, add the mapping between MAC capabilities and phy_caps. While doing so, we move the phylink_caps_params array up a bit to simplify future commits. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20250307173611.129125-12-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-18net: phylink: Use phy_caps_lookup for fixed-link configurationMaxime Chevallier1-13/+31
When phylink creates a fixed-link configuration, it finds a matching linkmode to set as the advertised, lp_advertising and supported modes based on the speed and duplex of the fixed link. Use the newly introduced phy_caps_lookup to get these modes instead of phy_lookup_settings(). This has the side effect that the matched settings and configured linkmodes may now contain several linkmodes (the intersection of supported linkmodes from the phylink settings and the linkmodes that match speed/duplex) instead of the one from phy_lookup_settings(). Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20250307173611.129125-10-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-18net: phy: phy_caps: Allow looking-up link caps based on speed and duplexMaxime Chevallier1-8/+9
As the link_caps array is efficient for <speed,duplex> lookups, implement a function for speed/duplex lookups that matches a given mask. This replicates to some extent the phy_lookup_settings() behaviour, matching full link_capabilities instead of a single linkmode. phy.c's phy_santize_settings() and phylink's phylink_ethtool_ksettings_set() performs such lookup using the phy_settings table, but are only interested in the actual speed/duplex that were matched, rathet than the individual linkmode. Similar to phy_lookup_settings(), the newly introduced phy_caps_lookup() will run through the link_caps[] array by descending speed/duplex order. If the link_capabilities for a given <speed/duplex> tuple intersects the passed linkmodes, we consider that a match. Similar to phy_lookup_settings(), we also allow passing an 'exact' boolean, allowing non-exact match. Here, we MUST always match the linkmodes mask, but we allow matching on lower speed settings. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20250307173611.129125-8-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-07net: phylink: Remove unused phylink_init_eeeDr. David Alan Gilbert1-18/+0
phylink_init_eee() is currently unused. It was last added in 2019 by commit 86e58135bc4a ("net: phylink: add phylink_init_eee() helper") but it didn't actually wire a use up. It had previous been removed in 2017 by commit 939eae25d9a5 ("phylink: remove phylink_init_eee()"). Remove it again. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/20250306184534.246152-1-linux@treblig.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05net: phylink: use pl->link_interface in phylink_expects_phy()Choong Yong Liang1-1/+1
The phylink_expects_phy() function allows MAC drivers to check if they are expecting a PHY to attach. The checking condition in phylink_expects_phy() aims to achieve the same result as the checking condition in phylink_attach_phy(). However, the checking condition in phylink_expects_phy() uses pl->link_config.interface, while phylink_attach_phy() uses pl->link_interface. Initially, both pl->link_interface and pl->link_config.interface are set to SGMII, and pl->cfg_link_an_mode is set to MLO_AN_INBAND. When the interface switches from SGMII to 2500BASE-X, pl->link_config.interface is updated by phylink_major_config(). At this point, pl->cfg_link_an_mode remains MLO_AN_INBAND, and pl->link_config.interface is set to 2500BASE-X. Subsequently, when the STMMAC interface is taken down administratively and brought back up, it is blocked by phylink_expects_phy(). Since phylink_expects_phy() and phylink_attach_phy() aim to achieve the same result, phylink_expects_phy() should check pl->link_interface, which never changes, instead of pl->link_config.interface, which is updated by phylink_major_config(). Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Choong Yong Liang <yong.liang.choong@linux.intel.com> Link: https://patch.msgid.link/20250227121522.1802832-2-yong.liang.choong@linux.intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-14net: remove phylink_pcs .neg_mode booleanRussell King (Oracle)1-25/+5
As all PCS are using the neg_mode parameter rather than the legacy an_mode, remove the ability to use the legacy an_mode. We remove the tests in the phylink code, unconditionally passing the PCS neg_mode parameter to PCS methods, and remove setting the flag from drivers. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tidPn-0040hd-2R@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-14net: phylink: add support for notifying PCS about EEERussell King (Oracle)1-3/+22
There are hooks in the stmmac driver into XPCS to control the EEE settings when LPI is configured at the MAC. This bypasses the layering. To allow this to be removed from the stmmac driver, add two new methods for PCS to inform them when the LPI/EEE enablement state changes at the MAC. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1thRQ3-003w6u-RH@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-6/+9
Cross-merge networking fixes after downstream PR (net-6.14-rc3). No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-12net: phylink: provide phylink_mac_implements_lpi()Russell King (Oracle)1-2/+1
Provide a helper to determine whether the MAC operations structure implements the LPI operations, which will be used by both phylink and DSA. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1thR9g-003vX6-4s@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-11net: phylink: make configuring clock-stop dependent on MAC supportRussell King (Oracle)1-6/+9
We should not be configuring the PHYs clock-stop settings unless the MAC supports phylink managed EEE. Make this dependent on MAC support. This was noticed in a suspicious RCU usage report from the kernel test robot (the suspicious RCU usage due to calling phy_detach() remains unaddressed, but is triggered by the error this was generating.) Fixes: 03abf2a7c654 ("net: phylink: add EEE management") Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://patch.msgid.link/E1tgjNn-003q0w-Pw@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-20net: phylink: fix regression when binding a PHYRussell King (Oracle)1-1/+5
Some PHYs don't support clause 45 access, and return -EOPNOTSUPP from phy_modify_mmd(), which causes phylink_bringup_phy() to fail. Prevent this failure by allowing -EOPNOTSUPP to also mean success. Reported-by: Jiawen Wu <jiawenwu@trustnetic.com> Tested-by: Jiawen Wu <jiawenwu@trustnetic.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/E1tZp1a-001V62-DT@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-20net: phylink: always do a major config when attaching a SFP PHYRussell King (Oracle)1-6/+5
Background: https://lore.kernel.org/r/20250107123615.161095-1-ericwouds@gmail.com Since adding negotiation of in-band capabilities, it is no longer sufficient to just look at the MLO_AN_xxx mode and PHY interface to decide whether to do a major configuration, since the result now depends on the capabilities of the attaching PHY. Always trigger a major configuration in this case. Testing log: https://lore.kernel.org/r/f20c9744-3953-40e7-a9c9-5534b25d2e2a@gmail.com Reported-by: Eric Woudstra <ericwouds@gmail.com> Tested-by: Eric Woudstra <ericwouds@gmail.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2025-01-16net: phylink: add EEE managementRussell King (Oracle)1-5/+133
Add EEE management to phylink, making use of the phylib implementation. This will only be used where a MAC driver populates the methods and capabilities bitfield, otherwise we keep our old behaviour. Phylink will keep track of the EEE configuration, including the clock stop abilities at each end of the MAC to PHY link, programming the PHY appropriately and preserving the LPI configuration should the PHY go away. Phylink will call into the MAC driver when LPI needs to be enabled or disabled, with the requirement that the MAC have LPI disabled prior to the netdev being brought up (in other words, it will only call mac_disable_tx_lpi() if it has already called mac_enable_tx_lpi().) Support for phylink managed EEE is enabled by populating both tx_lpi MAC operations method pointers, and filling in both LPI interfaces and capabilities. If the methods are provided but the LPI interfaces or capabilities remain empty, this indicates to phylink that EEE is implemented by the driver but the hardware it is driving does not support EEE, and thus the ethtool set_eee() and get_eee() methods will return EOPNOTSUPP. No validation of the LPI timer value is performed by this patch. For interface modes which do not support LPI, we make no attempt to manipulate the phylib EEE advertisement, but instead refuse to activate LPI at the MAC, noting it at debug message level. We also restrict the advertisement and reported userspace support linkmode masks according to the lpi_capabilities provided to phylink by the MAC driver. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Link: https://patch.msgid.link/E1tYADq-0014Pn-J1@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-16net: phylink: add phylink_link_is_up() helperRussell King (Oracle)1-5/+6
Add a helper to determine whether the link is up or down. Currently this is only used in one location, but becomes necessary to test when reconfiguring EEE. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Link: https://patch.msgid.link/E1tYADl-0014Ph-EV@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-15net: phylink: provide fixed state for 1000base-X and 2500base-XRussell King (Oracle)1-10/+19
When decoding clause 22 state, if in-band is disabled and using either 1000base-X or 2500base-X, rather than reporting link-down, we know the speed, and we only support full duplex. Pause modes taken from XPCS. This fixes a problem reported by Eric Woudstra. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1tXGei-000EtL-Fn@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-15net: phylink: use neg_mode in phylink_mii_c22_pcs_decode_state()Russell King (Oracle)1-4/+8
Rather than using the state of the Autoneg bit, which is unreliable with the new PCS neg mode support, use the passed neg_mode to decide whether to decode the link partner advertisement data. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1tXGed-000EtF-CN@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-15net: phylink: pass neg_mode into c22 state decoderRussell King (Oracle)1-2/+5
Pass the current neg_mode into phylink_mii_c22_pcs_get_state() and phylink_mii_c22_pcs_decode_state(). Update all users of phylink PCS that use these functions. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1tXGeY-000Et9-8g@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-15net: phylink: pass neg_mode into .pcs_get_state() methodRussell King (Oracle)1-1/+1
Pass the current neg_mode into the .pcs_get_state() method. Update all users of phylink PCS. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1tXGeT-000Et3-4L@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-15net: phylink: use pcs_neg_mode in phylink_mac_pcs_get_state()Russell King (Oracle)1-6/+16
As in-band AN no longer just depends on MLO_AN_INBAND + Autoneg bit, we need to take account of the pcs_neg_mode when deciding how to initialise the speed, duplex and pause state members before calling into the .pcs_neg_mode() method. Add this. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Tested-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/E1tXGeO-000Esx-0r@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-06net: phylink: add support for PCS supported_interfaces bitmapRussell King (Oracle)1-0/+11
Add support for the PCS to specify which interfaces it supports, which can be used by MAC drivers to build the main supported_interfaces bitmap. Phylink also validates that the PCS returned by the MAC driver supports the interface that the MAC was asked for. An empty supported_interfaces bitmap from the PCS indicates that it does not provide this information, and we handle that appropriately. Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tTffL-007RoD-1Y@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-15net: phylink: improve phylink_sfp_config_phy() error message with missing PHY driverVladimir Oltean1-0/+7
It seems that phylink does not support driving PHYs in SFP modules using the Generic PHY or Generic Clause 45 PHY driver. I've come to this conclusion after analyzing these facts: - sfp_sm_probe_phy(), who is our caller here, first calls phy_device_register() and then sfp_add_phy() -> ... -> phylink_sfp_connect_phy(). - phydev->supported is populated by phy_probe() - phy_probe() is usually called synchronously from phy_device_register() via phy_bus_match(), if a precise device driver is found for the PHY. In that case, phydev->supported has a good chance of being set to a non-zero mask. - There is an exceptional case for the PHYs for which phy_bus_match() didn't find a driver. Those devices sit for a while without a driver, then phy_attach_direct() force-binds the genphy_c45_driver or genphy_driver to them. Again, this triggers phy_probe() and renders a good chance of phydev->supported being populated, assuming compatibility with genphy_read_abilities() or genphy_c45_pma_read_abilities(). - phylink_sfp_config_phy() does not support the exceptional case of retrieving phydev->supported from the Generic PHY driver, due to its code flow. It expects the phydev->supported mask to already be non-empty, because it first calls phylink_validate() on it, and only calls phylink_attach_phy() if that succeeds. Thus, phylink_attach_phy() -> phy_attach_direct() has no chance of running. It is not my wish to change the state of affairs by altering the code flow, but merely to document the limitation rather than have the current unspecific error: [ 61.800079] mv88e6085 d0032004.mdio-mii:12 sfp: validation with support 00,00000000,00000000,00000000 failed: -EINVAL [ 61.820743] sfp sfp: sfp_add_phy failed: -EINVAL On the premise that an empty phydev->supported is going to make phylink_validate() fail anyway, and that this is caused by a missing PHY driver, it would be more informative to single out that case, undercut the entire phylink_sfp_config_phy() call, including phylink_validate(), and print a more specific message for this common gotcha: [ 37.076403] mv88e6085 d0032004.mdio-mii:12 sfp: PHY i2c:sfp:16 (id 0x01410cc2) has no driver loaded [ 37.089157] mv88e6085 d0032004.mdio-mii:12 sfp: Drivers which handle known common cases: CONFIG_BCM84881_PHY, CONFIG_MARVELL_PHY [ 37.108047] sfp sfp: sfp_add_phy failed: -EINVAL Link: https://lore.kernel.org/netdev/20241113144229.3ff4bgsalvj7spb7@skbuf/ Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/20241212140834.278894-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04net: phylink: remove phylink_phy_no_inband()Russell King (Oracle)1-21/+6
Remove phylink_phy_no_inband() now that we are handling the lack of inband negotiation by querying the capabilities of the PHY and PCS, and the BCM84881 PHY driver provides us the information necessary to make the decision. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tIUsO-006IUt-KN@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04net: phylink: add negotiation of in-band capabilitiesRussell King (Oracle)1-10/+144
Support for in-band signalling with Serdes links is uncertain. Some PHYs do not support in-band for e.g. SGMII. Some PCS do not support in-band for 2500Base-X. Some PCS require in-band for Base-X protocols. Simply using what is in DT is insufficient when we have hot-pluggable PHYs e.g. in the form of SFP modules, which may not provide the in-band signalling. In order to address this, we have introduced phy_inband_caps() and pcs_inband_caps() functions to allow phylink to retrieve the capabilities from each end of the PCS/PHY link. This commit adds code to resolve whether in-band will be used in the various scenarios that we have: In-band not being used, PHY present using SGMII or Base-X, PHY not present. We also deal with no capabilties provided. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tIUsJ-006IUn-H3@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04net: phylink: add pcs_inband_caps() methodRussell King (Oracle)1-0/+60
Add a pcs_inband_caps() method to query the PCS for its inband link capabilities, and use this to determine whether link modes used with optical SFPs can be supported. When a PCS does not provide a method, we allow inband negotiation to be either on or off, making this a no-op until the pcs_inband_caps() method is implemented by a PCS driver. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tIUs4-006IUU-7K@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04net: phylink: add debug for phylink_major_config()Russell King (Oracle)1-1/+26
Now that we have a more complexity in phylink_major_config(), augment the debugging so we can see what's going on there. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tIUrZ-006ITt-Fa@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04net: phylink: split cur_link_an_mode into requested and activeRussell King (Oracle)1-29/+31
There is an interdependence between the current link_an_mode and pcs_neg_mode that some drivers rely upon to know whether inband or PHY mode will be used. In order to support detection of PCS and PHY inband capabilities resulting in automatic selection of inband or PHY mode, we need to cater for this, and support changing the MAC link_an_mode. However, we end up with an inter-dependency between the current link_an_mode and pcs_neg_mode. To solve this, split the current link_an_mode into the requested link_an_mode and active link_an_mode. The requested link_an_mode will always be passed to phylink_pcs_neg_mode(), and the active link_an_mode will be used for everything else, and only updated during phylink_major_config(). This will ensure that phylink_pcs_neg_mode()'s link_an_mode will not depend on the active link_an_mode that will, in a future patch, depend on pcs_neg_mode. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tIUrU-006ITn-Ai@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-04net: phylink: pass phylink and pcs into phylink_pcs_neg_mode()Russell King (Oracle)1-13/+13
Move the call to phylink_pcs_neg_mode() in phylink_major_config() after we have selected the appropriate PCS to allow the PCS to be passed in. Add struct phylink and struct phylink_pcs pointers to phylink_pcs_neg_mode() and pass in the appropriate structures. Set pl->pcs_neg_mode before returning, and remove the return value. This will allow the capabilities of the PCS and any PHY to be used when deciding which pcs_neg_mode should be used. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1tIUrP-006ITh-6u@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-6/+8
Cross-merge networking fixes after downstream PR (net-6.12-rc8). Conflicts: tools/testing/selftests/net/.gitignore 252e01e68241 ("selftests: net: add netlink-dumps to .gitignore") be43a6b23829 ("selftests: ncdevmem: Move ncdevmem under drivers/net/hw") https://lore.kernel.org/all/20241113122359.1b95180a@canb.auug.org.au/ drivers/net/phy/phylink.c 671154f174e0 ("net: phylink: ensure PHY momentary link-fails are handled") 7530ea26c810 ("net: phylink: remove "using_mac_select_pcs"") Adjacent changes: drivers/net/ethernet/stmicro/stmmac/dwmac-intel-plat.c 5b366eae7193 ("stmmac: dwmac-intel-plat: fix call balance of tx_clk handling routines") e96321fad3ad ("net: ethernet: Switch back to struct platform_driver::remove()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-13net: phylink: ensure PHY momentary link-fails are handledRussell King (Oracle)1-6/+8
Normally, phylib won't notify changes in quick succession. However, as a result of commit 3e43b903da04 ("net: phy: Immediately call adjust_link if only tx_lpi_enabled changes") this is no longer true - it is now possible that phy_link_down() and phy_link_up() will both complete before phylink's resolver has run, which means it'll miss that pl->phy_state.link momentarily became false. Rename "mac_link_dropped" to be more generic "link_failed" since it will cover more than the MAC/PCS end of the link failing, and arrange to set this in phylink_phy_change() if we notice that the PHY reports that the link is down. This will ensure that we capture an EEE reconfiguration event. Fixes: 3e43b903da04 ("net: phy: Immediately call adjust_link if only tx_lpi_enabled changes") Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://patch.msgid.link/E1tAtcW-002RBS-LB@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-11net: phylink: clean up phylink_resolve()Russell King (Oracle)1-19/+16
Now that we have reduced the indentation level, clean up the code formatting. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1t9RQz-002Ff5-EA@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-11net: phylink: remove switch() statement in resolve handlingRussell King (Oracle)1-49/+45
The switch() statement doesn't sit very well with the preceeding if() statements, so let's just convert everything to if()s. As a result of the two preceding commits, there is now only one case in the switch() statement. Remove the switch statement and reduce the code indentation. Code reformatting will be in the following commit. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Link: https://patch.msgid.link/E1t9RQu-002Fez-AA@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>