/*
 * Copyright (c) 2013-2015, Mellanox Technologies, Ltd.  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.
 */

#ifndef __MLX5_WQ_H__
#define __MLX5_WQ_H__

#include <linux/mlx5/mlx5_ifc.h>
#include <linux/mlx5/cq.h>
#include <linux/mlx5/qp.h>

struct mlx5_wq_param {
        int             linear;
        int             buf_numa_node;
        int             db_numa_node;
};

struct mlx5_wq_ctrl {
        struct mlx5_core_dev    *mdev;
        struct mlx5_buf         buf;
        struct mlx5_db          db;
};

struct mlx5_frag_wq_ctrl {
        struct mlx5_core_dev    *mdev;
        struct mlx5_frag_buf    frag_buf;
        struct mlx5_db          db;
};

struct mlx5_wq_cyc {
        void                    *buf;
        __be32                  *db;
        u16                     sz_m1;
        u8                      log_stride;
};

struct mlx5_wq_qp {
        struct mlx5_wq_cyc      rq;
        struct mlx5_wq_cyc      sq;
};

struct mlx5_cqwq {
        struct mlx5_frag_buf    frag_buf;
        __be32                  *db;
        u32                     sz_m1;
        u32                     frag_sz_m1;
        u32                     cc; /* consumer counter */
        u8                      log_sz;
        u8                      log_stride;
        u8                      log_frag_strides;
};

struct mlx5_wq_ll {
        void                    *buf;
        __be32                  *db;
        __be16                  *tail_next;
        u16                     sz_m1;
        u16                     head;
        u16                     wqe_ctr;
        u16                     cur_sz;
        u8                      log_stride;
};

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);
u32 mlx5_wq_cyc_get_size(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,
                      struct mlx5_wq_ctrl *wq_ctrl);

int mlx5_cqwq_create(struct mlx5_core_dev *mdev, struct mlx5_wq_param *param,
                     void *cqc, struct mlx5_cqwq *wq,
                     struct mlx5_frag_wq_ctrl *wq_ctrl);
u32 mlx5_cqwq_get_size(struct mlx5_cqwq *wq);

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);
u32 mlx5_wq_ll_get_size(struct mlx5_wq_ll *wq);

void mlx5_wq_destroy(struct mlx5_wq_ctrl *wq_ctrl);
void mlx5_cqwq_destroy(struct mlx5_frag_wq_ctrl *wq_ctrl);

static inline u16 mlx5_wq_cyc_ctr2ix(struct mlx5_wq_cyc *wq, u16 ctr)
{
        return ctr & wq->sz_m1;
}

static inline void *mlx5_wq_cyc_get_wqe(struct mlx5_wq_cyc *wq, u16 ix)
{
        return wq->buf + (ix << wq->log_stride);
}

static inline int mlx5_wq_cyc_cc_bigger(u16 cc1, u16 cc2)
{
        int equal   = (cc1 == cc2);
        int smaller = 0x8000 & (cc1 - cc2);

        return !equal && !smaller;
}

static inline u32 mlx5_cqwq_get_ci(struct mlx5_cqwq *wq)
{
        return wq->cc & wq->sz_m1;
}

static inline void *mlx5_cqwq_get_wqe(struct mlx5_cqwq *wq, u32 ix)
{
        unsigned int frag = (ix >> wq->log_frag_strides);

        return wq->frag_buf.frags[frag].buf +
                ((wq->frag_sz_m1 & ix) << wq->log_stride);
}

static inline u32 mlx5_cqwq_get_wrap_cnt(struct mlx5_cqwq *wq)
{
        return wq->cc >> wq->log_sz;
}

static inline void mlx5_cqwq_pop(struct mlx5_cqwq *wq)
{
        wq->cc++;
}

static inline void mlx5_cqwq_update_db_record(struct mlx5_cqwq *wq)
{
        *wq->db = cpu_to_be32(wq->cc & 0xffffff);
}

static inline struct mlx5_cqe64 *mlx5_cqwq_get_cqe(struct mlx5_cqwq *wq)
{
        u32 ci = mlx5_cqwq_get_ci(wq);
        struct mlx5_cqe64 *cqe = mlx5_cqwq_get_wqe(wq, ci);
        u8 cqe_ownership_bit = cqe->op_own & MLX5_CQE_OWNER_MASK;
        u8 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 */
        dma_rmb();

        return cqe;
}

static inline int mlx5_wq_ll_is_full(struct mlx5_wq_ll *wq)
{
        return wq->cur_sz == wq->sz_m1;
}

static inline int mlx5_wq_ll_is_empty(struct mlx5_wq_ll *wq)
{
        return !wq->cur_sz;
}

static inline void *mlx5_wq_ll_get_wqe(struct mlx5_wq_ll *wq, u16 ix)
{
        return wq->buf + (ix << wq->log_stride);
}

static inline void mlx5_wq_ll_push(struct mlx5_wq_ll *wq, u16 head_next)
{
        wq->head = head_next;
        wq->wqe_ctr++;
        wq->cur_sz++;
}

static inline void mlx5_wq_ll_pop(struct mlx5_wq_ll *wq, __be16 ix,
                                  __be16 *next_tail_next)
{
        *wq->tail_next = ix;
        wq->tail_next = next_tail_next;
        wq->cur_sz--;
}

static inline void mlx5_wq_ll_update_db_record(struct mlx5_wq_ll *wq)
{
        *wq->db = cpu_to_be32(wq->wqe_ctr);
}

#endif /* __MLX5_WQ_H__ */