net: sfp: add support for setting signalling rate

Add support to the SFP layer to allow phylink to set the signalling
rate for a SFP module. The rate given will be in units of kilo-baud
(1000 baud).

Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index dc9a740b1ff770b24b102d64649ef1747ac74235..f2106d17847a501b4f680f173eab506ffa21bbb6 100644 (file)
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -156,6 +156,23 @@ static const char *phylink_an_mode_str(unsigned int mode)
        return mode < ARRAY_SIZE(modestr) ? modestr[mode] : "unknown";
 }
 
+static unsigned int phylink_interface_signal_rate(phy_interface_t interface)
+{
+       switch (interface) {
+       case PHY_INTERFACE_MODE_SGMII:
+       case PHY_INTERFACE_MODE_1000BASEX: /* 1.25Mbd */
+               return 1250;
+       case PHY_INTERFACE_MODE_2500BASEX: /* 3.125Mbd */
+               return 3125;
+       case PHY_INTERFACE_MODE_5GBASER: /* 5.15625Mbd */
+               return 5156;
+       case PHY_INTERFACE_MODE_10GBASER: /* 10.3125Mbd */
+               return 10313;
+       default:
+               return 0;
+       }
+}
+
 /**
  * phylink_interface_max_speed() - get the maximum speed of a phy interface
  * @interface: phy interface mode defined by &typedef phy_interface_t
@@ -1025,6 +1042,7 @@ static void phylink_major_config(struct phylink *pl, bool restart,
 {
        struct phylink_pcs *pcs = NULL;
        bool pcs_changed = false;
+       unsigned int rate_kbd;
        int err;
 
        phylink_dbg(pl, "major config %s\n", phy_modes(state->interface));
@@ -1084,6 +1102,12 @@ static void phylink_major_config(struct phylink *pl, bool restart,
                                    ERR_PTR(err));
        }
 
+       if (pl->sfp_bus) {
+               rate_kbd = phylink_interface_signal_rate(state->interface);
+               if (rate_kbd)
+                       sfp_upstream_set_signal_rate(pl->sfp_bus, rate_kbd);
+       }
+
        phylink_pcs_poll_start(pl);
 }
 

diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index 9372e5a4cadcf5f76ce2253dbf01d6080756ddb5..e8dd47bffe4356cd5cf436242d871795e2681ecf 100644 (file)
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -575,6 +575,26 @@ static void sfp_upstream_clear(struct sfp_bus *bus)
        bus->upstream = NULL;
 }
 
+/**
+ * sfp_upstream_set_signal_rate() - set data signalling rate
+ * @bus: a pointer to the &struct sfp_bus structure for the sfp module
+ * @rate_kbd: signalling rate in units of 1000 baud
+ *
+ * Configure the rate select settings on the SFP module for the signalling
+ * rate (not the same as the data rate).
+ *
+ * Locks that may be held:
+ *  Phylink's state_mutex
+ *  rtnl lock
+ *  SFP's sm_mutex
+ */
+void sfp_upstream_set_signal_rate(struct sfp_bus *bus, unsigned int rate_kbd)
+{
+       if (bus->registered)
+               bus->socket_ops->set_signal_rate(bus->sfp, rate_kbd);
+}
+EXPORT_SYMBOL_GPL(sfp_upstream_set_signal_rate);
+
 /**
  * sfp_bus_find_fwnode() - parse and locate the SFP bus from fwnode
  * @fwnode: firmware node for the parent device (MAC or PHY)

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index bf7dac9977e1b89cfae39825976bc9ac0a0ad68d..34bf724c00c76b164d042c90754de56d19a13934 100644 (file)
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -2527,6 +2527,10 @@ static void sfp_stop(struct sfp *sfp)
        sfp_sm_event(sfp, SFP_E_DEV_DOWN);
 }
 
+static void sfp_set_signal_rate(struct sfp *sfp, unsigned int rate_kbd)
+{
+}
+
 static int sfp_module_info(struct sfp *sfp, struct ethtool_modinfo *modinfo)
 {
        /* locking... and check module is present */
@@ -2611,6 +2615,7 @@ static const struct sfp_socket_ops sfp_module_ops = {
        .detach = sfp_detach,
        .start = sfp_start,
        .stop = sfp_stop,
+       .set_signal_rate = sfp_set_signal_rate,
        .module_info = sfp_module_info,
        .module_eeprom = sfp_module_eeprom,
        .module_eeprom_by_page = sfp_module_eeprom_by_page,

diff --git a/drivers/net/phy/sfp.h b/drivers/net/phy/sfp.h
index 6cf1643214d3ef34c0dfdb716be9b76823f0d3d1..c7cb50d1009992b46f657ac9c579f7cfe7ea48b2 100644 (file)
--- a/drivers/net/phy/sfp.h
+++ b/drivers/net/phy/sfp.h
@@ -19,6 +19,7 @@ struct sfp_socket_ops {
        void (*detach)(struct sfp *sfp);
        void (*start)(struct sfp *sfp);
        void (*stop)(struct sfp *sfp);
+       void (*set_signal_rate)(struct sfp *sfp, unsigned int rate_kbd);
        int (*module_info)(struct sfp *sfp, struct ethtool_modinfo *modinfo);
        int (*module_eeprom)(struct sfp *sfp, struct ethtool_eeprom *ee,
                             u8 *data);

diff --git a/include/linux/sfp.h b/include/linux/sfp.h
index ef06a195b3c2bc588f485364d3a6bd86f992dec5..2f66e03e9dbd0b314e26166183905fdb76618a41 100644 (file)
--- a/include/linux/sfp.h
+++ b/include/linux/sfp.h
@@ -556,6 +556,7 @@ int sfp_get_module_eeprom_by_page(struct sfp_bus *bus,
                                  struct netlink_ext_ack *extack);
 void sfp_upstream_start(struct sfp_bus *bus);
 void sfp_upstream_stop(struct sfp_bus *bus);
+void sfp_upstream_set_signal_rate(struct sfp_bus *bus, unsigned int rate_kbd);
 void sfp_bus_put(struct sfp_bus *bus);
 struct sfp_bus *sfp_bus_find_fwnode(const struct fwnode_handle *fwnode);
 int sfp_bus_add_upstream(struct sfp_bus *bus, void *upstream,
@@ -615,6 +616,11 @@ static inline void sfp_upstream_stop(struct sfp_bus *bus)
 {
 }
 
+static inline void sfp_upstream_set_signal_rate(struct sfp_bus *bus,
+                                               unsigned int rate_kbd)
+{
+}
+
 static inline void sfp_bus_put(struct sfp_bus *bus)
 {
 }