On Wed, Feb 21, 2024 at 02:04:19PM +0100, Romain Gantois wrote: > Some MAC drivers (e.g. stmmac) require a continuous receive clock signal to > be generated by a PCS that is handled by a standalone PCS driver. > > Such a PCS driver does not have access to a PHY device, thus cannot check > the PHY_F_RXC_ALWAYS_ON flag. They cannot check max_requires_rxc in the > phylink config either, since it is a private member. Therefore, a new flag > is needed to signal to the PCS that it should keep the RX clock signal up > at all times. > > Suggested-by: Russell King <linux@xxxxxxxxxxxxxxx> > Signed-off-by: Romain Gantois <romain.gantois@xxxxxxxxxxx> ... > @@ -549,6 +557,34 @@ void pcs_an_restart(struct phylink_pcs *pcs); > */ > void pcs_link_up(struct phylink_pcs *pcs, unsigned int neg_mode, > phy_interface_t interface, int speed, int duplex); > + > +/** > + * pcs_pre_init() - Configure PCS components necessary for MAC initialization > + * @pcs: a pointer to a &struct phylink_pcs. > + * > + * This function can be called by MAC drivers through the > + * phylink_pcs_pre_init() wrapper, before their hardware is initialized. It > + * should not be called after the link is brought up, as reconfiguring the PCS > + * at this point could break the link. > + * > + * Some MAC devices require specific hardware initialization to be performed by > + * their associated PCS device before they can properly initialize their own > + * hardware. An example of this is the initialization of stmmac controllers, > + * which requires an active REF_CLK signal to be provided by the PHY/PCS. > + * > + * By calling phylink_pcs_pre_init(), MAC drivers can ensure that the PCS is > + * setup in a way that allows for successful hardware initialization. > + * > + * The specific configuration performed by pcs_pre_init() is dependent on the > + * model of PCS and the requirements of the MAC device attached to it. PCS > + * driver authors should consider whether their target device is to be used in > + * conjunction with a MAC device whose driver calls phylink_pcs_pre_init(). MAC > + * driver authors should document their requirements for the PCS > + * pre-initialization. > + * > + */ > +int pcs_config(struct phylink_pcs *pcs); Hi Romain, Should this be pcs_pre_init instead of pcs_config? > + > #endif > > struct phylink *phylink_create(struct phylink_config *, ...
