kernel/linux.git/include/linux/phylink.h, branch v6.18.21

net: phylink: remove stale an_enabled from doc

2025-08-26T00:59:08+00:00

state->an_enabled was removed by commit 4ee9b0dcf09f ("net: phylink: remove an_enabled") but is left in mac_config() doc, so clean it. Signed-off-by: David Yang Reviewed-by: Russell King (Oracle) Link: https://patch.msgid.link/20250824013009.2443580-1-mmyangfl@gmail.com Signed-off-by: Jakub Kicinski

net: phylink: mac_link_(up|down)() clarifications

2025-04-23T01:21:53+00:00

As a result of an email from the fbnic author, I reviewed the phylink documentation, and I have decided to clarify the wording in the mac_link_(up|down)() kernel documentation as this was written from the point of view of mvneta/mvpp2 and is misleading. The documentation talks about forcing the link - indeed, this is what is done in the mvneta and mvpp2 drivers but not at the physical layer but the MACs idea, which has the effect of only allowing or stopping packet flow at the MAC. This "link" needs to be controlled when using a PHY or fixed link to start or stop packet flow at the MAC. However, as the MAC and PCS are tightly integrated, if the MACs idea of the link is forced down, it has the side effect that there is no way to determine that the media link has come up - in this mode, the MAC must be allowed to follow its built-in PCS so we can read the link state. Frame the documentation in more generic terms, to avoid the thought that the physical media link to the partner needs in some way to be forced up or down with these calls; it does not. If that were to be done, it would be a self-fulfilling prophecy - e.g. if the media link goes down, then mac_link_down() will be called, and if the media link is then placed into a forced down state, there is no possibility that the media link will ever come up again - clearly this is a wrong interpretation. These methods are notifications to the MAC about what has happened to the media link state - either from the PHY, or a PCS, or whatever mechanism fixed-link is using. Thus, reword them to get away from talking about changing link state to avoid confusion with media link state. This is not a change of any requirements of these methods. Also, remove the obsolete references to EEE for these methods, we now have the LPI functions for configuring the EEE parameters which renders this redundant, and also makes the passing of "phy" to the mac_link_up() function obsolete. Signed-off-by: Russell King (Oracle) Reviewed-by: Maxime Chevallier Link: https://patch.msgid.link/E1u5Ah5-001GO1-7E@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski

net: phylink: add functions to block/unblock rx clock stop

2025-03-25T14:58:04+00:00

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) Link: https://patch.msgid.link/E1tvO6k-008Vjt-MZ@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski

net: phylink: add phylink_prepare_resume()

2025-03-25T14:58:03+00:00

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) Link: https://patch.msgid.link/E1tvO6V-008Vjb-AP@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski

net: phylink: expand on .pcs_config() method documentation

2025-03-17T20:30:54+00:00

Expand on the requirements of the .pcs_config() method documentation, specifically mentioning that it should cause minimal disruption to an established link, and that it should return a positive non-zero value when requiring the .pcs_an_restart() method to be called. Signed-off-by: Russell King (Oracle) Link: https://patch.msgid.link/E1trb24-005oVq-Is@rmk-PC.armlinux.org.uk Signed-off-by: Paolo Abeni

net: phylink: Remove unused phylink_init_eee

2025-03-08T03:03:31+00:00

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 Reviewed-by: Russell King (Oracle) Link: https://patch.msgid.link/20250306184534.246152-1-linux@treblig.org Signed-off-by: Jakub Kicinski

net: remove phylink_pcs .neg_mode boolean

2025-02-15T01:09:50+00:00

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) Link: https://patch.msgid.link/E1tidPn-0040hd-2R@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski

net: phylink: add support for notifying PCS about EEE

2025-02-14T21:42:51+00:00

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) Link: https://patch.msgid.link/E1thRQ3-003w6u-RH@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski

net: phylink: provide phylink_mac_implements_lpi()

2025-02-13T02:20:04+00:00

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) Link: https://patch.msgid.link/E1thR9g-003vX6-4s@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski

net: phylink: add EEE management

2025-01-17T01:22:59+00:00

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) Reviewed-by: Jacob Keller Link: https://patch.msgid.link/E1tYADq-0014Pn-J1@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski