net/mlx5: EQ, Introduce atomic notifier chain subscription API

Use atomic_notifier_chain to fire firmware events at internal mlx5 core
components such as eswitch/fpga/clock/FW tracer/etc.., this is to
avoid explicit calls from low level mlx5_core to upper components and to
simplify the mlx5_core API for future developments.

Simply provide register/unregister notifiers API and call the notifier
chain on firmware async events.

Example: to subscribe to a FW event:
struct mlx5_nb port_event;

MLX5_NB_INIT(&port_event, port_event_handler, PORT_CHANGE);
mlx5_eq_notifier_register(mdev, &port_event);

where:
 - port_event_handler is the notifier block callback.
 - PORT_EVENT is the suffix of MLX5_EVENT_TYPE_PORT_CHANGE.

The above will guarantee that port_event_handler will receive all FW
events of the type MLX5_EVENT_TYPE_PORT_CHANGE.

To receive all FW/HW events one can subscribe to
MLX5_EVENT_TYPE_NOTIFY_ANY.

The next few patches will start moving all mlx5 core components to use
this new API and cleanup mlx5_eq_async_int misx handler from component
explicit calls and specific logic.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.h b/drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.h
index 21727d9eeb84..e06c6e16ffc9 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.h
@@ -78,6 +78,11 @@ do {									\
 		 __func__, __LINE__, current->pid,			\
 		##__VA_ARGS__)
 
+#define mlx5_core_warn_once(__dev, format, ...)				\
+	dev_warn_once(&(__dev)->pdev->dev, "%s:%d:(pid %d): " format,	\
+		      __func__, __LINE__, current->pid,			\
+		      ##__VA_ARGS__)
+
 #define mlx5_core_info(__dev, format, ...)				\
 	dev_info(&(__dev)->pdev->dev, format, ##__VA_ARGS__)