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/lib/eq.h b/drivers/net/ethernet/mellanox/mlx5/core/lib/eq.h
index 6d8c8a57d52b..c0fb6d72b695 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/eq.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/eq.h
@@ -4,6 +4,8 @@
 #ifndef __LIB_MLX5_EQ_H__
 #define __LIB_MLX5_EQ_H__
 #include <linux/mlx5/driver.h>
+#include <linux/mlx5/eq.h>
+#include <linux/mlx5/cq.h>
 
 #define MLX5_MAX_IRQ_NAME   (32)
 #define MLX5_EQE_SIZE       (sizeof(struct mlx5_eqe))
@@ -90,4 +92,7 @@ void mlx5_core_eq_free_irqs(struct mlx5_core_dev *dev);
 struct cpu_rmap *mlx5_eq_table_get_rmap(struct mlx5_core_dev *dev);
 #endif
 
+int mlx5_eq_notifier_register(struct mlx5_core_dev *dev, struct mlx5_nb *nb);
+int mlx5_eq_notifier_unregister(struct mlx5_core_dev *dev, struct mlx5_nb *nb);
+
 #endif