| Message ID | 20250507135331.76021-7-maxime.chevallier@bootlin.com |
|---|---|
| State | New |
| Headers | show |
| Series | Introduce an ethernet port representation | expand |
Hi Maxime, On Wednesday, 7 May 2025 15:53:22 CEST Maxime Chevallier wrote: > There are currently 4 PHY drivers that can drive downstream SFPs: > marvell.c, marvell10g.c, at803x.c and marvell-88x2222.c. Most of the > logic is boilerplate, either calling into generic phylib helpers (for > SFP PHY attach, bus attach, etc.) or performing the same tasks with a > bit of validation : > - Getting the module's expected interface mode > - Making sure the PHY supports it > - Optionnaly perform some configuration to make sure the PHY outputs > the right mode > > This can be made more generic by leveraging the phy_port, and its > configure_mii() callback which allows setting a port's interfaces when > the port is a serdes. > > Introduce a generic PHY SFP support. If a driver doesn't probe the SFP > bus itself, but an SFP phandle is found in devicetree/firmware, then the > generic PHY SFP support will be used, relying on port ops. > > PHY driver need to : > - Register a .attach_port() callback > - When a serdes port is registered to the PHY, drivers must set > port->interfaces to the set of PHY_INTERFACE_MODE the port can output > - If the port has limitations regarding speed, duplex and aneg, the > port can also fine-tune the final linkmodes that can be supported > - The port may register a set of ops, including .configure_mii(), that > will be called at module_insert time to adjust the interface based on > the module detected. > > Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> > --- > drivers/net/phy/phy_device.c | 107 +++++++++++++++++++++++++++++++++++ > include/linux/phy.h | 2 + > 2 files changed, 109 insertions(+) > > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c > index aaf0eccbefba..aca3a47cbb66 100644 > --- a/drivers/net/phy/phy_device.c > +++ b/drivers/net/phy/phy_device.c > @@ -1450,6 +1450,87 @@ void phy_sfp_detach(void *upstream, struct sfp_bus > *bus) } > EXPORT_SYMBOL(phy_sfp_detach); > > +static int phy_sfp_module_insert(void *upstream, const struct sfp_eeprom_id > *id) +{ > + struct phy_device *phydev = upstream; > + struct phy_port *port = phy_get_sfp_port(phydev); > + RCT > + __ETHTOOL_DECLARE_LINK_MODE_MASK(sfp_support); > + DECLARE_PHY_INTERFACE_MASK(interfaces); > + phy_interface_t iface; > + > + linkmode_zero(sfp_support); > + > + if (!port) > + return -EINVAL; > + > + sfp_parse_support(phydev->sfp_bus, id, sfp_support, interfaces); > + > + if (phydev->n_ports == 1) > + phydev->port = sfp_parse_port(phydev->sfp_bus, id, sfp_support); As mentionned below, this check looks a bit strange to me. Why are we only parsing the SFP port if the PHY device only has one registered port? > + > + linkmode_and(sfp_support, port->supported, sfp_support); > + > + if (linkmode_empty(sfp_support)) { > + dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n"); > + return -EINVAL; > + } > + > + iface = sfp_select_interface(phydev->sfp_bus, sfp_support); > + > + /* Check that this interface is supported */ > + if (!test_bit(iface, port->interfaces)) { > + dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n"); > + return -EINVAL; > + } > + > + if (port->ops && port->ops->configure_mii) > + return port->ops->configure_mii(port, true, iface); The name "configure_mii()" seems a bit narrow-scoped to me, as this callback might have to configure something else than a MII link. For example, if a DAC SFP module is inserted, the downstream side of the transciever will have to be configured to 1000Base-X or something similar. I'd suggest something like "post_sfp_insert()", please let me know what you think. > + > + return 0; > +} > + > +static void phy_sfp_module_remove(void *upstream) > +{ > + struct phy_device *phydev = upstream; > + struct phy_port *port = phy_get_sfp_port(phydev); > + > + if (port && port->ops && port->ops->configure_mii) > + port->ops->configure_mii(port, false, PHY_INTERFACE_MODE_NA); > + > + if (phydev->n_ports == 1) > + phydev->port = PORT_NONE; This check is a bit confusing to me. Could you please explain why you're only setting the phydev's SFP port to PORT_NONE if the PHY device only has one registered port? Shouldn't this be done regardless? > +} > + > +static void phy_sfp_link_up(void *upstream) > +{ > + struct phy_device *phydev = upstream; > + struct phy_port *port = phy_get_sfp_port(phydev); > + > + if (port && port->ops && port->ops->link_up) > + port->ops->link_up(port); > +} > + > +static void phy_sfp_link_down(void *upstream) > +{ > + struct phy_device *phydev = upstream; > + struct phy_port *port = phy_get_sfp_port(phydev); > + > + if (port && port->ops && port->ops->link_down) > + port->ops->link_down(port); > +} > + > +static const struct sfp_upstream_ops sfp_phydev_ops = { > + .attach = phy_sfp_attach, > + .detach = phy_sfp_detach, > + .module_insert = phy_sfp_module_insert, > + .module_remove = phy_sfp_module_remove, > + .link_up = phy_sfp_link_up, > + .link_down = phy_sfp_link_down, > + .connect_phy = phy_sfp_connect_phy, > + .disconnect_phy = phy_sfp_disconnect_phy, > +}; > + > static int phy_add_port(struct phy_device *phydev, struct phy_port *port) > { > int ret = 0; > @@ -3351,6 +3432,13 @@ static int phy_setup_ports(struct phy_device *phydev) > if (ret) > return ret; > > + /* Use generic SFP probing only if the driver didn't do so already */ > + if (!phydev->sfp_bus) { Should the phy_sfp_probe() API be changed to something explicitely legacy? I feel like people writing new PHY drivers could be confused if they see some other drivers calling phy_sfp_probe() and others not doing anything and still getting SFP busses. > + ret = phy_sfp_probe(phydev, &sfp_phydev_ops); > + if (ret) > + goto out; > + } > + > if (phydev->n_ports < phydev->max_n_ports) { > ret = phy_default_setup_single_port(phydev); > if (ret) > @@ -3384,6 +3472,25 @@ static int phy_setup_ports(struct phy_device *phydev) > return ret; > } > > +/** > + * phy_get_sfp_port() - Returns the first valid SFP port of a PHY > + * @phydev: pointer to the PHY device to get the SFP port from > + * > + * Returns: The first active SFP (serdes) port of a PHY device, NULL if > none + * exist. > + */ > +struct phy_port *phy_get_sfp_port(struct phy_device *phydev) I'd suggest "phy_get_active_sfp_port()". > +{ > + struct phy_port *port; > + > + list_for_each_entry(port, &phydev->ports, head) > + if (port->active && port->is_serdes) > + return port; > + > + return NULL; > +} > +EXPORT_SYMBOL_GPL(phy_get_sfp_port); > + > /** > * fwnode_mdio_find_device - Given a fwnode, find the mdio_device > * @fwnode: pointer to the mdio_device's fwnode > diff --git a/include/linux/phy.h b/include/linux/phy.h > index 0180f4d4fd7d..aef13fab8882 100644 > --- a/include/linux/phy.h > +++ b/include/linux/phy.h > @@ -2091,6 +2091,8 @@ int __phy_hwtstamp_set(struct phy_device *phydev, > struct kernel_hwtstamp_config *config, > struct netlink_ext_ack *extack); > > +struct phy_port *phy_get_sfp_port(struct phy_device *phydev); > + > extern const struct bus_type mdio_bus_type; > extern const struct class mdio_bus_class; Thanks!
Hi Romain, On Mon, 12 May 2025 10:38:52 +0200 Romain Gantois <romain.gantois@bootlin.com> wrote: > Hi Maxime, > > On Wednesday, 7 May 2025 15:53:22 CEST Maxime Chevallier wrote: > > There are currently 4 PHY drivers that can drive downstream SFPs: > > marvell.c, marvell10g.c, at803x.c and marvell-88x2222.c. Most of the > > logic is boilerplate, either calling into generic phylib helpers (for > > SFP PHY attach, bus attach, etc.) or performing the same tasks with a > > bit of validation : > > - Getting the module's expected interface mode > > - Making sure the PHY supports it > > - Optionnaly perform some configuration to make sure the PHY outputs > > the right mode > > > > This can be made more generic by leveraging the phy_port, and its > > configure_mii() callback which allows setting a port's interfaces when > > the port is a serdes. > > > > Introduce a generic PHY SFP support. If a driver doesn't probe the SFP > > bus itself, but an SFP phandle is found in devicetree/firmware, then the > > generic PHY SFP support will be used, relying on port ops. > > > > PHY driver need to : > > - Register a .attach_port() callback > > - When a serdes port is registered to the PHY, drivers must set > > port->interfaces to the set of PHY_INTERFACE_MODE the port can output > > - If the port has limitations regarding speed, duplex and aneg, the > > port can also fine-tune the final linkmodes that can be supported > > - The port may register a set of ops, including .configure_mii(), that > > will be called at module_insert time to adjust the interface based on > > the module detected. > > > > Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> > > --- > > drivers/net/phy/phy_device.c | 107 +++++++++++++++++++++++++++++++++++ > > include/linux/phy.h | 2 + > > 2 files changed, 109 insertions(+) > > > > diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c > > index aaf0eccbefba..aca3a47cbb66 100644 > > --- a/drivers/net/phy/phy_device.c > > +++ b/drivers/net/phy/phy_device.c > > @@ -1450,6 +1450,87 @@ void phy_sfp_detach(void *upstream, struct sfp_bus > > *bus) } > > EXPORT_SYMBOL(phy_sfp_detach); > > > > +static int phy_sfp_module_insert(void *upstream, const struct sfp_eeprom_id > > *id) +{ > > + struct phy_device *phydev = upstream; > > + struct phy_port *port = phy_get_sfp_port(phydev); > > + > > RCT Can't be done here, it won't build if in the other order... > > > + __ETHTOOL_DECLARE_LINK_MODE_MASK(sfp_support); > > + DECLARE_PHY_INTERFACE_MASK(interfaces); > > + phy_interface_t iface; > > + > > + linkmode_zero(sfp_support); > > + > > + if (!port) > > + return -EINVAL; > > + > > + sfp_parse_support(phydev->sfp_bus, id, sfp_support, interfaces); > > + > > + if (phydev->n_ports == 1) > > + phydev->port = sfp_parse_port(phydev->sfp_bus, id, > sfp_support); > > As mentionned below, this check looks a bit strange to me. Why are we only > parsing the SFP port if the PHY device only has one registered port? Because phydev->port is global to the PHY. If we have another port, then phydev->port must be handled differently so that SFP insertion / removal doesn't overwrite what the other port is. Handling of phydev->port is still fragile in this state of the series, I'll try to improve on that for V7 and document it better. > > + > > + linkmode_and(sfp_support, port->supported, sfp_support); > > + > > + if (linkmode_empty(sfp_support)) { > > + dev_err(&phydev->mdio.dev, "incompatible SFP module > inserted\n"); > > + return -EINVAL; > > + } > > + > > + iface = sfp_select_interface(phydev->sfp_bus, sfp_support); > > + > > + /* Check that this interface is supported */ > > + if (!test_bit(iface, port->interfaces)) { > > + dev_err(&phydev->mdio.dev, "incompatible SFP module > inserted\n"); > > + return -EINVAL; > > + } > > + > > + if (port->ops && port->ops->configure_mii) > > + return port->ops->configure_mii(port, true, iface); > > The name "configure_mii()" seems a bit narrow-scoped to me, as this callback > might have to configure something else than a MII link. For example, if a DAC > SFP module is inserted, the downstream side of the transciever will have to be > configured to 1000Base-X or something similar. In that regard, you can consider 1000BaseX as a MII mode (we do have PHY_INTERFACE_MODE_1000BASEX). > I'd suggest something like "post_sfp_insert()", please let me know what you > think. That's not intended to be SFP-specific though. post_sfp_insert() sounds lke the narrow-scoped name to me :) Here we are dealing with a PHy that has a media-side port that isn't a MDI port, but an MII interface like a MAC would usually export. There may be an SFP here, or something else entirely :) One thing though is that this series uses a mix of "is_serdes" and "configure_mii" to mean pretty-much the same thing, I'll make the names a bit more homogenous. > > + > > + return 0; > > +} > > + > > +static void phy_sfp_module_remove(void *upstream) > > +{ > > + struct phy_device *phydev = upstream; > > + struct phy_port *port = phy_get_sfp_port(phydev); > > + > > + if (port && port->ops && port->ops->configure_mii) > > + port->ops->configure_mii(port, false, PHY_INTERFACE_MODE_NA); > > + > > + if (phydev->n_ports == 1) > > + phydev->port = PORT_NONE; > > This check is a bit confusing to me. Could you please explain why you're only > setting the phydev's SFP port to PORT_NONE if the PHY device only has one > registered port? Shouldn't this be done regardless? So that we don't overwrite what the other port would have set :) but, that's a bit fragile as I said and probably not correct anyways, let me double-check that. Maxime
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index aaf0eccbefba..aca3a47cbb66 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1450,6 +1450,87 @@ void phy_sfp_detach(void *upstream, struct sfp_bus *bus) } EXPORT_SYMBOL(phy_sfp_detach); +static int phy_sfp_module_insert(void *upstream, const struct sfp_eeprom_id *id) +{ + struct phy_device *phydev = upstream; + struct phy_port *port = phy_get_sfp_port(phydev); + + __ETHTOOL_DECLARE_LINK_MODE_MASK(sfp_support); + DECLARE_PHY_INTERFACE_MASK(interfaces); + phy_interface_t iface; + + linkmode_zero(sfp_support); + + if (!port) + return -EINVAL; + + sfp_parse_support(phydev->sfp_bus, id, sfp_support, interfaces); + + if (phydev->n_ports == 1) + phydev->port = sfp_parse_port(phydev->sfp_bus, id, sfp_support); + + linkmode_and(sfp_support, port->supported, sfp_support); + + if (linkmode_empty(sfp_support)) { + dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n"); + return -EINVAL; + } + + iface = sfp_select_interface(phydev->sfp_bus, sfp_support); + + /* Check that this interface is supported */ + if (!test_bit(iface, port->interfaces)) { + dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n"); + return -EINVAL; + } + + if (port->ops && port->ops->configure_mii) + return port->ops->configure_mii(port, true, iface); + + return 0; +} + +static void phy_sfp_module_remove(void *upstream) +{ + struct phy_device *phydev = upstream; + struct phy_port *port = phy_get_sfp_port(phydev); + + if (port && port->ops && port->ops->configure_mii) + port->ops->configure_mii(port, false, PHY_INTERFACE_MODE_NA); + + if (phydev->n_ports == 1) + phydev->port = PORT_NONE; +} + +static void phy_sfp_link_up(void *upstream) +{ + struct phy_device *phydev = upstream; + struct phy_port *port = phy_get_sfp_port(phydev); + + if (port && port->ops && port->ops->link_up) + port->ops->link_up(port); +} + +static void phy_sfp_link_down(void *upstream) +{ + struct phy_device *phydev = upstream; + struct phy_port *port = phy_get_sfp_port(phydev); + + if (port && port->ops && port->ops->link_down) + port->ops->link_down(port); +} + +static const struct sfp_upstream_ops sfp_phydev_ops = { + .attach = phy_sfp_attach, + .detach = phy_sfp_detach, + .module_insert = phy_sfp_module_insert, + .module_remove = phy_sfp_module_remove, + .link_up = phy_sfp_link_up, + .link_down = phy_sfp_link_down, + .connect_phy = phy_sfp_connect_phy, + .disconnect_phy = phy_sfp_disconnect_phy, +}; + static int phy_add_port(struct phy_device *phydev, struct phy_port *port) { int ret = 0; @@ -3351,6 +3432,13 @@ static int phy_setup_ports(struct phy_device *phydev) if (ret) return ret; + /* Use generic SFP probing only if the driver didn't do so already */ + if (!phydev->sfp_bus) { + ret = phy_sfp_probe(phydev, &sfp_phydev_ops); + if (ret) + goto out; + } + if (phydev->n_ports < phydev->max_n_ports) { ret = phy_default_setup_single_port(phydev); if (ret) @@ -3384,6 +3472,25 @@ static int phy_setup_ports(struct phy_device *phydev) return ret; } +/** + * phy_get_sfp_port() - Returns the first valid SFP port of a PHY + * @phydev: pointer to the PHY device to get the SFP port from + * + * Returns: The first active SFP (serdes) port of a PHY device, NULL if none + * exist. + */ +struct phy_port *phy_get_sfp_port(struct phy_device *phydev) +{ + struct phy_port *port; + + list_for_each_entry(port, &phydev->ports, head) + if (port->active && port->is_serdes) + return port; + + return NULL; +} +EXPORT_SYMBOL_GPL(phy_get_sfp_port); + /** * fwnode_mdio_find_device - Given a fwnode, find the mdio_device * @fwnode: pointer to the mdio_device's fwnode diff --git a/include/linux/phy.h b/include/linux/phy.h index 0180f4d4fd7d..aef13fab8882 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -2091,6 +2091,8 @@ int __phy_hwtstamp_set(struct phy_device *phydev, struct kernel_hwtstamp_config *config, struct netlink_ext_ack *extack); +struct phy_port *phy_get_sfp_port(struct phy_device *phydev); + extern const struct bus_type mdio_bus_type; extern const struct class mdio_bus_class;
There are currently 4 PHY drivers that can drive downstream SFPs: marvell.c, marvell10g.c, at803x.c and marvell-88x2222.c. Most of the logic is boilerplate, either calling into generic phylib helpers (for SFP PHY attach, bus attach, etc.) or performing the same tasks with a bit of validation : - Getting the module's expected interface mode - Making sure the PHY supports it - Optionnaly perform some configuration to make sure the PHY outputs the right mode This can be made more generic by leveraging the phy_port, and its configure_mii() callback which allows setting a port's interfaces when the port is a serdes. Introduce a generic PHY SFP support. If a driver doesn't probe the SFP bus itself, but an SFP phandle is found in devicetree/firmware, then the generic PHY SFP support will be used, relying on port ops. PHY driver need to : - Register a .attach_port() callback - When a serdes port is registered to the PHY, drivers must set port->interfaces to the set of PHY_INTERFACE_MODE the port can output - If the port has limitations regarding speed, duplex and aneg, the port can also fine-tune the final linkmodes that can be supported - The port may register a set of ops, including .configure_mii(), that will be called at module_insert time to adjust the interface based on the module detected. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> --- drivers/net/phy/phy_device.c | 107 +++++++++++++++++++++++++++++++++++ include/linux/phy.h | 2 + 2 files changed, 109 insertions(+)