netdev: expose DPLL pin handle for netdevice

In case netdevice represents a SyncE port, the user needs to understand
the connection between netdevice and associated DPLL pin. There might me
multiple netdevices pointing to the same pin, in case of VF/SF
implementation.

Add a IFLA Netlink attribute to nest the DPLL pin handle, similar to
how it is implemented for devlink port. Add a struct dpll_pin pointer
to netdev and protect access to it by RTNL. Expose netdev_dpll_pin_set()
and netdev_dpll_pin_clear() helpers to the drivers so they can set/clear
the DPLL pin relationship to netdev.

Note that during the lifetime of struct dpll_pin the pin handle does not
change. Therefore it is save to access it lockless. It is drivers
responsibility to call netdev_dpll_pin_clear() before dpll_pin_put().

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 37 insertions, 1 deletions

diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index 2202310c10cd..bbc480cd2932 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -101,6 +101,21 @@ struct dpll_pin_properties {
 	struct dpll_pin_frequency *freq_supported;
 };
 
+#if IS_ENABLED(CONFIG_DPLL)
+size_t dpll_msg_pin_handle_size(struct dpll_pin *pin);
+int dpll_msg_add_pin_handle(struct sk_buff *msg, struct dpll_pin *pin);
+#else
+static inline size_t dpll_msg_pin_handle_size(struct dpll_pin *pin)
+{
+	return 0;
+}
+
+static inline int dpll_msg_add_pin_handle(struct sk_buff *msg, struct dpll_pin *pin)
+{
+	return 0;
+}
+#endif
+
 struct dpll_device *
 dpll_device_get(u64 clock_id, u32 dev_driver_id, struct module *module);
 
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 0896aaa91dd7..db3d8429d50d 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -79,6 +79,8 @@ struct xdp_buff;
 struct xdp_frame;
 struct xdp_metadata_ops;
 struct xdp_md;
+/* DPLL specific */
+struct dpll_pin;
 
 typedef u32 xdp_features_t;
 
@@ -2049,6 +2051,9 @@ enum netdev_ml_priv_type {
  *			SET_NETDEV_DEVLINK_PORT macro. This pointer is static
  *			during the time netdevice is registered.
  *
+ *	@dpll_pin: Pointer to the SyncE source pin of a DPLL subsystem,
+ *		   where the clock is recovered.
+ *
  *	FIXME: cleanup struct net_device such that network protocol info
  *	moves out.
  */
@@ -2405,6 +2410,10 @@ struct net_device {
 	struct rtnl_hw_stats64	*offload_xstats_l3;
 
 	struct devlink_port	*devlink_port;
+
+#if IS_ENABLED(CONFIG_DPLL)
+	struct dpll_pin		*dpll_pin;
+#endif
 };
 #define to_net_dev(d) container_of(d, struct net_device, dev)
 
@@ -3940,6 +3949,18 @@ int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name);
 int dev_get_port_parent_id(struct net_device *dev,
 			   struct netdev_phys_item_id *ppid, bool recurse);
 bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b);
+void netdev_dpll_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin);
+void netdev_dpll_pin_clear(struct net_device *dev);
+
+static inline struct dpll_pin *netdev_dpll_pin(const struct net_device *dev)
+{
+#if IS_ENABLED(CONFIG_DPLL)
+	return dev->dpll_pin;
+#else
+	return NULL;
+#endif
+}
+
 struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again);
 struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 				    struct netdev_queue *txq, int *ret);
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index ce3117df9cec..fac351a93aed 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -376,7 +376,7 @@ enum {
 
 	IFLA_GSO_IPV4_MAX_SIZE,
 	IFLA_GRO_IPV4_MAX_SIZE,
-
+	IFLA_DPLL_PIN,
 	__IFLA_MAX
 };