net/mlx5e: Reset RQ doorbell counter before moving RQ state from RST to RDY

Initialize RQ doorbell counters to zero prior to moving an RQ from RST
to RDY state. Per HW spec, when RQ is back to RDY state, the descriptor
ID on the completion is reset. The doorbell record must comply.

Fixes: 8276ea13 ("net/mlx5e: Report and recover from CQE with error on RQ")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Reported-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en/txrx.h

@@ -179,6 +179,14 @@ mlx5e_tx_dma_unmap(struct device *pdev, struct mlx5e_sq_dma *dma)
 	}
 }
 
+static inline void mlx5e_rqwq_reset(struct mlx5e_rq *rq)
+{
+	if (rq->wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ)
+		mlx5_wq_ll_reset(&rq->mpwqe.wq);
+	else
+		mlx5_wq_cyc_reset(&rq->wqe.wq);
+}
+
 /* SW parser related functions */
 
 struct mlx5e_swp_spec {

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

@@ -712,6 +712,9 @@ int mlx5e_modify_rq_state(struct mlx5e_rq *rq, int curr_state, int next_state)
 	if (!in)
 		return -ENOMEM;
 
+	if (curr_state == MLX5_RQC_STATE_RST && next_state == MLX5_RQC_STATE_RDY)
+		mlx5e_rqwq_reset(rq);
+
 	rqc = MLX5_ADDR_OF(modify_rq_in, in, ctx);
 
 	MLX5_SET(modify_rq_in, in, rq_state, curr_state);

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

@@ -94,6 +94,13 @@ void mlx5_wq_cyc_wqe_dump(struct mlx5_wq_cyc *wq, u16 ix, u8 nstrides)
 	print_hex_dump(KERN_WARNING, "", DUMP_PREFIX_OFFSET, 16, 1, wqe, len, false);
 }
 
+void mlx5_wq_cyc_reset(struct mlx5_wq_cyc *wq)
+{
+	wq->wqe_ctr = 0;
+	wq->cur_sz = 0;
+	mlx5_wq_cyc_update_db_record(wq);
+}
+
 int mlx5_wq_qp_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 		      void *qpc, struct mlx5_wq_qp *wq,
 		      struct mlx5_wq_ctrl *wq_ctrl)
@@ -192,6 +199,19 @@ int mlx5_cqwq_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 	return err;
 }
 
+static void mlx5_wq_ll_init_list(struct mlx5_wq_ll *wq)
+{
+	struct mlx5_wqe_srq_next_seg *next_seg;
+	int i;
+
+	for (i = 0; i < wq->fbc.sz_m1; i++) {
+		next_seg = mlx5_wq_ll_get_wqe(wq, i);
+		next_seg->next_wqe_index = cpu_to_be16(i + 1);
+	}
+	next_seg = mlx5_wq_ll_get_wqe(wq, i);
+	wq->tail_next = &next_seg->next_wqe_index;
+}
+
 int mlx5_wq_ll_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 		      void *wqc, struct mlx5_wq_ll *wq,
 		      struct mlx5_wq_ctrl *wq_ctrl)
@@ -199,9 +219,7 @@ int mlx5_wq_ll_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 	u8 log_wq_stride = MLX5_GET(wq, wqc, log_wq_stride);
 	u8 log_wq_sz     = MLX5_GET(wq, wqc, log_wq_sz);
 	struct mlx5_frag_buf_ctrl *fbc = &wq->fbc;
-	struct mlx5_wqe_srq_next_seg *next_seg;
 	int err;
-	int i;
 
 	err = mlx5_db_alloc_node(mdev, &wq_ctrl->db, param->db_numa_node);
 	if (err) {
@@ -220,13 +238,7 @@ int mlx5_wq_ll_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 
 	mlx5_init_fbc(wq_ctrl->buf.frags, log_wq_stride, log_wq_sz, fbc);
 
-	for (i = 0; i < fbc->sz_m1; i++) {
-		next_seg = mlx5_wq_ll_get_wqe(wq, i);
-		next_seg->next_wqe_index = cpu_to_be16(i + 1);
-	}
-	next_seg = mlx5_wq_ll_get_wqe(wq, i);
-	wq->tail_next = &next_seg->next_wqe_index;
-
+	mlx5_wq_ll_init_list(wq);
 	wq_ctrl->mdev = mdev;
 
 	return 0;
@@ -237,6 +249,15 @@ int mlx5_wq_ll_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 	return err;
 }
 
+void mlx5_wq_ll_reset(struct mlx5_wq_ll *wq)
+{
+	wq->head = 0;
+	wq->wqe_ctr = 0;
+	wq->cur_sz = 0;
+	mlx5_wq_ll_init_list(wq);
+	mlx5_wq_ll_update_db_record(wq);
+}
+
 void mlx5_wq_destroy(struct mlx5_wq_ctrl *wq_ctrl)
 {
 	mlx5_frag_buf_free(wq_ctrl->mdev, &wq_ctrl->buf);

drivers/net/ethernet/mellanox/mlx5/core/wq.h

@@ -80,6 +80,7 @@ int mlx5_wq_cyc_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 		       void *wqc, struct mlx5_wq_cyc *wq,
 		       struct mlx5_wq_ctrl *wq_ctrl);
 void mlx5_wq_cyc_wqe_dump(struct mlx5_wq_cyc *wq, u16 ix, u8 nstrides);
+void mlx5_wq_cyc_reset(struct mlx5_wq_cyc *wq);
 
 int mlx5_wq_qp_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 		      void *qpc, struct mlx5_wq_qp *wq,
@@ -92,6 +93,7 @@ int mlx5_cqwq_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 int mlx5_wq_ll_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
 		      void *wqc, struct mlx5_wq_ll *wq,
 		      struct mlx5_wq_ctrl *wq_ctrl);
+void mlx5_wq_ll_reset(struct mlx5_wq_ll *wq);
 
 void mlx5_wq_destroy(struct mlx5_wq_ctrl *wq_ctrl);