net/mlx5: Generate PPS IN event on new function for shared clock

jira LE-3615
Rebuild_History Non-Buildable kernel-5.14.0-570.28.1.el9_6
commit-author Jianbo Liu <jianbol@nvidia.com>
commit 39c1202

As a specific function (mdev) is chosen to send MTPPSE command to
firmware, the event is generated only on that function. When that
function is unloaded, the PPS event can't be forward to PTP device,
even when there are other functions in the group, and PTP device is
not destroyed. To resolve this problem, need to send MTPPSE again from
new function, and dis-arm the event on old function after that.

PPS events are handled by EQ notifier. The async EQs and notifiers are
destroyed in mlx5_eq_table_destroy() which is called before
mlx5_cleanup_clock(). During the period between
mlx5_eq_table_destroy() and mlx5_cleanup_clock(), the events can't be
handled. To avoid event loss, add mlx5_clock_unload() in mlx5_unload()
to arm the event on other available function, and mlx5_clock_load in
mlx5_load() for symmetry.

	Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
	Reviewed-by: Carolina Jubran <cjubran@nvidia.com>
	Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
	Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
	Signed-off-by: Paolo Abeni <pabeni@redhat.com>

(cherry picked from commit 39c1202)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c

@@ -90,6 +90,7 @@ struct mlx5_clock_priv {
 	struct mlx5_clock clock;
 	struct mlx5_core_dev *mdev;
 	struct mutex lock; /* protect mdev and used in PTP callbacks */
+	struct mlx5_core_dev *event_mdev;
 };
 
 static struct mlx5_clock_priv *clock_priv(struct mlx5_clock *clock)
@@ -691,6 +692,11 @@ static int mlx5_extts_configure(struct ptp_clock_info *ptp,
 		goto unlock;
 
 	err = mlx5_set_mtppse(mdev, pin, 0, MLX5_EVENT_MODE_REPETETIVE & on);
+	if (err)
+		goto unlock;
+
+	clock->pps_info.pin_armed[pin] = on;
+	clock_priv(clock)->event_mdev = mdev;
 
 unlock:
 	mlx5_clock_unlock(clock);
@@ -1417,6 +1423,90 @@ static void mlx5_shared_clock_unregister(struct mlx5_core_dev *mdev)
 	mlx5_devcom_unregister_component(mdev->clock_state->compdev);
 }
 
+static void mlx5_clock_arm_pps_in_event(struct mlx5_clock *clock,
+					struct mlx5_core_dev *new_mdev,
+					struct mlx5_core_dev *old_mdev)
+{
+	struct ptp_clock_info *ptp_info = &clock->ptp_info;
+	struct mlx5_clock_priv *cpriv = clock_priv(clock);
+	int i;
+
+	for (i = 0; i < ptp_info->n_pins; i++) {
+		if (ptp_info->pin_config[i].func != PTP_PF_EXTTS ||
+		    !clock->pps_info.pin_armed[i])
+			continue;
+
+		if (new_mdev) {
+			mlx5_set_mtppse(new_mdev, i, 0, MLX5_EVENT_MODE_REPETETIVE);
+			cpriv->event_mdev = new_mdev;
+		} else {
+			cpriv->event_mdev = NULL;
+		}
+
+		if (old_mdev)
+			mlx5_set_mtppse(old_mdev, i, 0, MLX5_EVENT_MODE_DISABLE);
+	}
+}
+
+void mlx5_clock_load(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_clock *clock = mdev->clock;
+	struct mlx5_clock_priv *cpriv;
+
+	if (!MLX5_CAP_GEN(mdev, device_frequency_khz))
+		return;
+
+	INIT_WORK(&mdev->clock_state->out_work, mlx5_pps_out);
+	MLX5_NB_INIT(&mdev->clock_state->pps_nb, mlx5_pps_event, PPS_EVENT);
+	mlx5_eq_notifier_register(mdev, &mdev->clock_state->pps_nb);
+
+	if (!clock->shared) {
+		mlx5_clock_arm_pps_in_event(clock, mdev, NULL);
+		return;
+	}
+
+	cpriv = clock_priv(clock);
+	mlx5_devcom_comp_lock(mdev->clock_state->compdev);
+	mlx5_clock_lock(clock);
+	if (mdev == cpriv->mdev && mdev != cpriv->event_mdev)
+		mlx5_clock_arm_pps_in_event(clock, mdev, cpriv->event_mdev);
+	mlx5_clock_unlock(clock);
+	mlx5_devcom_comp_unlock(mdev->clock_state->compdev);
+}
+
+void mlx5_clock_unload(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_core_dev *peer_dev, *next = NULL;
+	struct mlx5_clock *clock = mdev->clock;
+	struct mlx5_devcom_comp_dev *pos;
+
+	if (!MLX5_CAP_GEN(mdev, device_frequency_khz))
+		return;
+
+	if (!clock->shared) {
+		mlx5_clock_arm_pps_in_event(clock, NULL, mdev);
+		goto out;
+	}
+
+	mlx5_devcom_comp_lock(mdev->clock_state->compdev);
+	mlx5_devcom_for_each_peer_entry(mdev->clock_state->compdev, peer_dev, pos) {
+		if (peer_dev->clock && peer_dev != mdev) {
+			next = peer_dev;
+			break;
+		}
+	}
+
+	mlx5_clock_lock(clock);
+	if (mdev == clock_priv(clock)->event_mdev)
+		mlx5_clock_arm_pps_in_event(clock, next, mdev);
+	mlx5_clock_unlock(clock);
+	mlx5_devcom_comp_unlock(mdev->clock_state->compdev);
+
+out:
+	mlx5_eq_notifier_unregister(mdev, &mdev->clock_state->pps_nb);
+	cancel_work_sync(&mdev->clock_state->out_work);
+}
+
 static struct mlx5_clock null_clock;
 
 int mlx5_init_clock(struct mlx5_core_dev *mdev)
@@ -1456,10 +1546,6 @@ int mlx5_init_clock(struct mlx5_core_dev *mdev)
 		}
 	}
 
-	INIT_WORK(&mdev->clock_state->out_work, mlx5_pps_out);
-	MLX5_NB_INIT(&mdev->clock_state->pps_nb, mlx5_pps_event, PPS_EVENT);
-	mlx5_eq_notifier_register(mdev, &mdev->clock_state->pps_nb);
-
 	return 0;
 }
 
@@ -1468,9 +1554,6 @@ void mlx5_cleanup_clock(struct mlx5_core_dev *mdev)
 	if (!MLX5_CAP_GEN(mdev, device_frequency_khz))
 		return;
 
-	mlx5_eq_notifier_unregister(mdev, &mdev->clock_state->pps_nb);
-	cancel_work_sync(&mdev->clock_state->out_work);
-
 	if (mdev->clock->shared)
 		mlx5_shared_clock_unregister(mdev);
 	else

drivers/net/ethernet/mellanox/mlx5/core/lib/clock.h

@@ -42,6 +42,7 @@ struct mlx5_pps {
 	u8                         enabled;
 	u64                        min_npps_period;
 	u64                        min_out_pulse_duration_ns;
+	bool                       pin_armed[MAX_PIN_NUM];
 };
 
 struct mlx5_timer {
@@ -84,6 +85,8 @@ typedef ktime_t (*cqe_ts_to_ns)(struct mlx5_clock *, u64);
 #if IS_ENABLED(CONFIG_PTP_1588_CLOCK)
 int mlx5_init_clock(struct mlx5_core_dev *mdev);
 void mlx5_cleanup_clock(struct mlx5_core_dev *mdev);
+void mlx5_clock_load(struct mlx5_core_dev *mdev);
+void mlx5_clock_unload(struct mlx5_core_dev *mdev);
 
 static inline int mlx5_clock_get_ptp_index(struct mlx5_core_dev *mdev)
 {
@@ -117,6 +120,8 @@ static inline ktime_t mlx5_real_time_cyc2time(struct mlx5_clock *clock,
 #else
 static inline int mlx5_init_clock(struct mlx5_core_dev *mdev) { return 0; }
 static inline void mlx5_cleanup_clock(struct mlx5_core_dev *mdev) {}
+static inline void mlx5_clock_load(struct mlx5_core_dev *mdev) {}
+static inline void mlx5_clock_unload(struct mlx5_core_dev *mdev) {}
 static inline int mlx5_clock_get_ptp_index(struct mlx5_core_dev *mdev)
 {
 	return -1;

drivers/net/ethernet/mellanox/mlx5/core/main.c

@@ -1358,6 +1358,8 @@ static int mlx5_load(struct mlx5_core_dev *dev)
 		goto err_eq_table;
 	}
 
+	mlx5_clock_load(dev);
+
 	err = mlx5_fw_tracer_init(dev->tracer);
 	if (err) {
 		mlx5_core_err(dev, "Failed to init FW tracer %d\n", err);
@@ -1441,6 +1443,7 @@ static int mlx5_load(struct mlx5_core_dev *dev)
 	mlx5_hv_vhca_cleanup(dev->hv_vhca);
 	mlx5_fw_reset_events_stop(dev);
 	mlx5_fw_tracer_cleanup(dev->tracer);
+	mlx5_clock_unload(dev);
 	mlx5_eq_table_destroy(dev);
 err_eq_table:
 	mlx5_irq_table_destroy(dev);
@@ -1467,6 +1470,7 @@ static void mlx5_unload(struct mlx5_core_dev *dev)
 	mlx5_hv_vhca_cleanup(dev->hv_vhca);
 	mlx5_fw_reset_events_stop(dev);
 	mlx5_fw_tracer_cleanup(dev->tracer);
+	mlx5_clock_unload(dev);
 	mlx5_eq_table_destroy(dev);
 	mlx5_irq_table_destroy(dev);
 	mlx5_pagealloc_stop(dev);