[PATCH net-next RFC v3 12/14] net/mlx5: Add support for fw live patch event

[Moshe Shemesh]

Firmware live patch event notifies the driver that the firmware was just
updated using live patch. In such case the driver should not reload or
re-initiate entities, part to updating the firmware version and
re-initiate the firmware tracer which can be updated by live patch with
new strings database to help debugging an issue.

Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>
---
 .../mellanox/mlx5/core/diag/fw_tracer.c       | 31 +++++++++++++++++++
 .../mellanox/mlx5/core/diag/fw_tracer.h       |  1 +
 .../ethernet/mellanox/mlx5/core/fw_reset.c    | 27 ++++++++++++++++
 include/linux/mlx5/device.h                   |  1 +
 4 files changed, 60 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
index ad3594c4afcb..08dae045d185 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.c
@@ -1064,6 +1064,37 @@ void mlx5_fw_tracer_destroy(struct mlx5_fw_tracer *tracer)
 	kvfree(tracer);
 }
 
+int mlx5_fw_tracer_recreate_strings_db(struct mlx5_fw_tracer *tracer)
+{
+	struct mlx5_core_dev *dev;
+	int err;
+
+	if (IS_ERR_OR_NULL(tracer))
+		return -EINVAL;
+
+	cancel_work_sync(&tracer->read_fw_strings_work);
+	mlx5_fw_tracer_clean_ready_list(tracer);
+	mlx5_fw_tracer_clean_print_hash(tracer);
+	mlx5_fw_tracer_clean_saved_traces_array(tracer);
+	mlx5_fw_tracer_free_strings_db(tracer);
+
+	dev = tracer->dev;
+	err = mlx5_query_mtrc_caps(tracer);
+	if (err) {
+		mlx5_core_dbg(dev, "FWTracer: Failed to query capabilities %d\n", err);
+		return err;
+	}
+
+	err = mlx5_fw_tracer_allocate_strings_db(tracer);
+	if (err) {
+		mlx5_core_warn(dev, "FWTracer: Allocate strings DB failed %d\n", err);
+		return err;
+	}
+	mlx5_fw_tracer_init_saved_traces_array(tracer);
+
+	return 0;
+}
+
 static int fw_tracer_event(struct notifier_block *nb, unsigned long action, void *data)
 {
 	struct mlx5_fw_tracer *tracer = mlx5_nb_cof(nb, struct mlx5_fw_tracer, nb);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.h b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.h
index 40601fba80ba..1a755098aeeb 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/fw_tracer.h
@@ -191,5 +191,6 @@ void mlx5_fw_tracer_destroy(struct mlx5_fw_tracer *tracer);
 int mlx5_fw_tracer_trigger_core_dump_general(struct mlx5_core_dev *dev);
 int mlx5_fw_tracer_get_saved_traces_objects(struct mlx5_fw_tracer *tracer,
 					    struct devlink_fmsg *fmsg);
+int mlx5_fw_tracer_recreate_strings_db(struct mlx5_fw_tracer *tracer);
 
 #endif
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
index 0df2ad9d555c..13a5e226d331 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fw_reset.c
@@ -2,6 +2,7 @@
 /* Copyright (c) 2020, Mellanox Technologies inc.  All rights reserved. */
 
 #include "fw_reset.h"
+#include "diag/fw_tracer.h"
 
 enum {
 	MLX5_FW_RESET_FLAGS_RESET_REQUESTED,
@@ -13,6 +14,7 @@ struct mlx5_fw_reset {
 	struct mlx5_core_dev *dev;
 	struct mlx5_nb nb;
 	struct workqueue_struct *wq;
+	struct work_struct fw_live_patch_work;
 	struct work_struct reset_request_work;
 	struct work_struct reset_reload_work;
 	struct work_struct reset_now_work;
@@ -187,6 +189,27 @@ static void mlx5_sync_reset_set_reset_requested(struct mlx5_core_dev *dev)
 	mlx5_start_sync_reset_poll(dev);
 }
 
+static void mlx5_fw_live_patch_event(struct work_struct *work)
+{
+	struct mlx5_fw_reset *fw_reset = container_of(work, struct mlx5_fw_reset,
+						      fw_live_patch_work);
+	struct mlx5_core_dev *dev = fw_reset->dev;
+	struct mlx5_fw_tracer *tracer;
+
+	mlx5_core_info(dev, "Live patch updated firmware version: %d.%d.%d\n", fw_rev_maj(dev),
+		       fw_rev_min(dev), fw_rev_sub(dev));
+
+	tracer = dev->tracer;
+	if (IS_ERR_OR_NULL(tracer))
+		return;
+
+	mlx5_fw_tracer_cleanup(tracer);
+	if (mlx5_fw_tracer_recreate_strings_db(tracer))
+		mlx5_core_err(dev, "Failed to recreate FW tracer strings DB\n");
+	if (mlx5_fw_tracer_init(tracer))
+		mlx5_core_err(dev, "Failed to re-initialize FW tracer\n");
+}
+
 static void mlx5_sync_reset_request_event(struct work_struct *work)
 {
 	struct mlx5_fw_reset *fw_reset = container_of(work, struct mlx5_fw_reset,
@@ -360,6 +383,9 @@ static int fw_reset_event_notifier(struct notifier_block *nb, unsigned long acti
 	struct mlx5_eqe *eqe = data;
 
 	switch (eqe->sub_type) {
+	case MLX5_GENERAL_SUBTYPE_FW_LIVE_PATCH_EVENT:
+			queue_work(fw_reset->wq, &fw_reset->fw_live_patch_work);
+		break;
 	case MLX5_GENERAL_SUBTYPE_PCI_SYNC_FOR_FW_UPDATE_EVENT:
 		mlx5_sync_reset_events_handle(fw_reset, eqe);
 		break;
@@ -404,6 +430,7 @@ int mlx5_fw_reset_events_init(struct mlx5_core_dev *dev)
 	fw_reset->dev = dev;
 	dev->priv.fw_reset = fw_reset;
 
+	INIT_WORK(&fw_reset->fw_live_patch_work, mlx5_fw_live_patch_event);
 	INIT_WORK(&fw_reset->reset_request_work, mlx5_sync_reset_request_event);
 	INIT_WORK(&fw_reset->reset_reload_work, mlx5_sync_reset_reload_work);
 	INIT_WORK(&fw_reset->reset_now_work, mlx5_sync_reset_now_event);
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 4d3376e20f5e..ab5bedd9d3d3 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -366,6 +366,7 @@ enum {
 enum {
 	MLX5_GENERAL_SUBTYPE_DELAY_DROP_TIMEOUT = 0x1,
 	MLX5_GENERAL_SUBTYPE_PCI_POWER_CHANGE_EVENT = 0x5,
+	MLX5_GENERAL_SUBTYPE_FW_LIVE_PATCH_EVENT = 0x7,
 	MLX5_GENERAL_SUBTYPE_PCI_SYNC_FOR_FW_UPDATE_EVENT = 0x8,
 };
 
-- 
2.17.1