text: /*
   * Copyright (c) 2015, Mellanox Technologies. All rights reserved.
   *
   * This software is available to you under a choice of one of two
   * licenses.  You may choose to be licensed under the terms of the GNU
   * General Public License (GPL) Version 2, available from the file
   * COPYING in the main directory of this source tree, or the
   * OpenIB.org BSD license below:
   *
   *     Redistribution and use in source and binary forms, with or
   *     without modification, are permitted provided that the following
   *     conditions are met:
   *
   *      - Redistributions of source code must retain the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer.
   *
   *      - Redistributions in binary form must reproduce the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer in the documentation and/or other materials
   *        provided with the distribution.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  
  #include "en.h"
  
  struct mlx5_cqe64 *mlx5e_get_cqe(struct mlx5e_cq *cq)
  {
  	struct mlx5_cqwq *wq = &cq->wq;
  	u32 ci = mlx5_cqwq_get_ci(wq);
  	struct mlx5_cqe64 *cqe = mlx5_cqwq_get_wqe(wq, ci);
  	int cqe_ownership_bit = cqe->op_own & MLX5_CQE_OWNER_MASK;
  	int sw_ownership_val = mlx5_cqwq_get_wrap_cnt(wq) & 1;
  
  	if (cqe_ownership_bit != sw_ownership_val)
  		return NULL;
  
  	/* ensure cqe content is read after cqe ownership bit */
  	rmb();
  
  	return cqe;
  }
  
  int mlx5e_napi_poll(struct napi_struct *napi, int budget)
  {
  	struct mlx5e_channel *c = container_of(napi, struct mlx5e_channel,
  					       napi);
  	bool busy = false;
  	int work_done;
  	int i;
  
  	clear_bit(MLX5E_CHANNEL_NAPI_SCHED, &c->flags);
  
  	for (i = 0; i < c->num_tc; i++)
  		busy |= mlx5e_poll_tx_cq(&c->sq[i].cq);
  
  	work_done = mlx5e_poll_rx_cq(&c->rq.cq, budget);
  	busy |= work_done == budget;
  	busy |= mlx5e_post_rx_wqes(&c->rq);
  
  	if (busy)
  		return budget;
  
  	napi_complete_done(napi, work_done);
  
  	/* avoid losing completion event during/after polling cqs */
  	if (test_bit(MLX5E_CHANNEL_NAPI_SCHED, &c->flags)) {
  		napi_schedule(napi);
  		return work_done;
  	}
  
  	for (i = 0; i < c->num_tc; i++)
  		mlx5e_cq_arm(&c->sq[i].cq);
  	mlx5e_cq_arm(&c->rq.cq);
  
  	return work_done;
  }
  
  void mlx5e_completion_event(struct mlx5_core_cq *mcq)
  {
  	struct mlx5e_cq *cq = container_of(mcq, struct mlx5e_cq, mcq);
  
  	set_bit(MLX5E_CHANNEL_NAPI_SCHED, &cq->channel->flags);
  	barrier();
  	napi_schedule(cq->napi);
  }
  
  void mlx5e_cq_error_event(struct mlx5_core_cq *mcq, enum mlx5_event event)
  {
  	struct mlx5e_cq *cq = container_of(mcq, struct mlx5e_cq, mcq);
  	struct mlx5e_channel *c = cq->channel;
  	struct mlx5e_priv *priv = c->priv;
  	struct net_device *netdev = priv->netdev;
  
  	netdev_err(netdev, "%s: cqn=0x%.6x event=0x%.2x\n",
  		   __func__, mcq->cqn, event);
  }
  