/*
 * Copyright (c) 2017 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 <net/addrconf.h>
#include <linux/etherdevice.h>
#include <linux/mlx5/vport.h>

#include "mlx5_core.h"
#include "lib/mlx5.h"
#include "fpga/conn.h"

#define MLX5_FPGA_PKEY 0xFFFF
#define MLX5_FPGA_PKEY_INDEX 0 /* RoCE PKEY 0xFFFF is always at index 0 */
#define MLX5_FPGA_RECV_SIZE 2048
#define MLX5_FPGA_PORT_NUM 1
#define MLX5_FPGA_CQ_BUDGET 64

static int mlx5_fpga_conn_map_buf(struct mlx5_fpga_conn *conn,
                                  struct mlx5_fpga_dma_buf *buf)
{
        struct device *dma_device;
        int err = 0;

        if (unlikely(!buf->sg[0].data))
                goto out;

        dma_device = mlx5_core_dma_dev(conn->fdev->mdev);
        buf->sg[0].dma_addr = dma_map_single(dma_device, buf->sg[0].data,
                                             buf->sg[0].size, buf->dma_dir);
        err = dma_mapping_error(dma_device, buf->sg[0].dma_addr);
        if (unlikely(err)) {
                mlx5_fpga_warn(conn->fdev, "DMA error on sg 0: %d\n", err);
                err = -ENOMEM;
                goto out;
        }

        if (!buf->sg[1].data)
                goto out;

        buf->sg[1].dma_addr = dma_map_single(dma_device, buf->sg[1].data,
                                             buf->sg[1].size, buf->dma_dir);
        err = dma_mapping_error(dma_device, buf->sg[1].dma_addr);
        if (unlikely(err)) {
                mlx5_fpga_warn(conn->fdev, "DMA error on sg 1: %d\n", err);
                dma_unmap_single(dma_device, buf->sg[0].dma_addr,
                                 buf->sg[0].size, buf->dma_dir);
                err = -ENOMEM;
        }

out:
        return err;
}

static void mlx5_fpga_conn_unmap_buf(struct mlx5_fpga_conn *conn,
                                     struct mlx5_fpga_dma_buf *buf)
{
        struct device *dma_device;

        dma_device = mlx5_core_dma_dev(conn->fdev->mdev);
        if (buf->sg[1].data)
                dma_unmap_single(dma_device, buf->sg[1].dma_addr,
                                 buf->sg[1].size, buf->dma_dir);

        if (likely(buf->sg[0].data))
                dma_unmap_single(dma_device, buf->sg[0].dma_addr,
                                 buf->sg[0].size, buf->dma_dir);
}

static int mlx5_fpga_conn_post_recv(struct mlx5_fpga_conn *conn,
                                    struct mlx5_fpga_dma_buf *buf)
{
        struct mlx5_wqe_data_seg *data;
        unsigned int ix;
        int err = 0;

        err = mlx5_fpga_conn_map_buf(conn, buf);
        if (unlikely(err))
                goto out;

        if (unlikely(conn->qp.rq.pc - conn->qp.rq.cc >= conn->qp.rq.size)) {
                mlx5_fpga_conn_unmap_buf(conn, buf);
                return -EBUSY;
        }

        ix = conn->qp.rq.pc & (conn->qp.rq.size - 1);
        data = mlx5_wq_cyc_get_wqe(&conn->qp.wq.rq, ix);
        data->byte_count = cpu_to_be32(buf->sg[0].size);
        data->lkey = cpu_to_be32(conn->fdev->conn_res.mkey);
        data->addr = cpu_to_be64(buf->sg[0].dma_addr);

        conn->qp.rq.pc++;
        conn->qp.rq.bufs[ix] = buf;

        /* Make sure that descriptors are written before doorbell record. */
        dma_wmb();
        *conn->qp.wq.rq.db = cpu_to_be32(conn->qp.rq.pc & 0xffff);
out:
        return err;
}

static void mlx5_fpga_conn_notify_hw(struct mlx5_fpga_conn *conn, void *wqe)
{
        /* ensure wqe is visible to device before updating doorbell record */
        dma_wmb();
        *conn->qp.wq.sq.db = cpu_to_be32(conn->qp.sq.pc);
        /* Make sure that doorbell record is visible before ringing */
        wmb();
        mlx5_write64(wqe, conn->fdev->conn_res.uar->map + MLX5_BF_OFFSET);
}

static void mlx5_fpga_conn_post_send(struct mlx5_fpga_conn *conn,
                                     struct mlx5_fpga_dma_buf *buf)
{
        struct mlx5_wqe_ctrl_seg *ctrl;
        struct mlx5_wqe_data_seg *data;
        unsigned int ix, sgi;
        int size = 1;

        ix = conn->qp.sq.pc & (conn->qp.sq.size - 1);

        ctrl = mlx5_wq_cyc_get_wqe(&conn->qp.wq.sq, ix);
        data = (void *)(ctrl + 1);

        for (sgi = 0; sgi < ARRAY_SIZE(buf->sg); sgi++) {
                if (!buf->sg[sgi].data)
                        break;
                data->byte_count = cpu_to_be32(buf->sg[sgi].size);
                data->lkey = cpu_to_be32(conn->fdev->conn_res.mkey);
                data->addr = cpu_to_be64(buf->sg[sgi].dma_addr);
                data++;
                size++;
        }

        ctrl->imm = 0;
        ctrl->fm_ce_se = MLX5_WQE_CTRL_CQ_UPDATE;
        ctrl->opmod_idx_opcode = cpu_to_be32(((conn->qp.sq.pc & 0xffff) << 8) |
                                             MLX5_OPCODE_SEND);
        ctrl->qpn_ds = cpu_to_be32(size | (conn->qp.qpn << 8));

        conn->qp.sq.pc++;
        conn->qp.sq.bufs[ix] = buf;
        mlx5_fpga_conn_notify_hw(conn, ctrl);
}

int mlx5_fpga_conn_send(struct mlx5_fpga_conn *conn,
                        struct mlx5_fpga_dma_buf *buf)
{
        unsigned long flags;
        int err;

        if (!conn->qp.active)
                return -ENOTCONN;

        buf->dma_dir = DMA_TO_DEVICE;
        err = mlx5_fpga_conn_map_buf(conn, buf);
        if (err)
                return err;

        spin_lock_irqsave(&conn->qp.sq.lock, flags);

        if (conn->qp.sq.pc - conn->qp.sq.cc >= conn->qp.sq.size) {
                list_add_tail(&buf->list, &conn->qp.sq.backlog);
                goto out_unlock;
        }

        mlx5_fpga_conn_post_send(conn, buf);

out_unlock:
        spin_unlock_irqrestore(&conn->qp.sq.lock, flags);
        return err;
}

static int mlx5_fpga_conn_post_recv_buf(struct mlx5_fpga_conn *conn)
{
        struct mlx5_fpga_dma_buf *buf;
        int err;

        buf = kzalloc(sizeof(*buf) + MLX5_FPGA_RECV_SIZE, 0);
        if (!buf)
                return -ENOMEM;

        buf->sg[0].data = (void *)(buf + 1);
        buf->sg[0].size = MLX5_FPGA_RECV_SIZE;
        buf->dma_dir = DMA_FROM_DEVICE;

        err = mlx5_fpga_conn_post_recv(conn, buf);
        if (err)
                kfree(buf);

        return err;
}

static int mlx5_fpga_conn_create_mkey(struct mlx5_core_dev *mdev, u32 pdn,
                                      u32 *mkey)
{
        int inlen = MLX5_ST_SZ_BYTES(create_mkey_in);
        void *mkc;
        u32 *in;
        int err;

        in = kvzalloc(inlen, GFP_KERNEL);
        if (!in)
                return -ENOMEM;

        mkc = MLX5_ADDR_OF(create_mkey_in, in, memory_key_mkey_entry);
        MLX5_SET(mkc, mkc, access_mode_1_0, MLX5_MKC_ACCESS_MODE_PA);
        MLX5_SET(mkc, mkc, lw, 1);
        MLX5_SET(mkc, mkc, lr, 1);

        MLX5_SET(mkc, mkc, pd, pdn);
        MLX5_SET(mkc, mkc, length64, 1);
        MLX5_SET(mkc, mkc, qpn, 0xffffff);

        err = mlx5_core_create_mkey(mdev, mkey, in, inlen);

        kvfree(in);
        return err;
}

static void mlx5_fpga_conn_rq_cqe(struct mlx5_fpga_conn *conn,
                                  struct mlx5_cqe64 *cqe, u8 status)
{
        struct mlx5_fpga_dma_buf *buf;
        int ix, err;

        ix = be16_to_cpu(cqe->wqe_counter) & (conn->qp.rq.size - 1);
        buf = conn->qp.rq.bufs[ix];
        conn->qp.rq.bufs[ix] = NULL;
        conn->qp.rq.cc++;

        if (unlikely(status && (status != MLX5_CQE_SYNDROME_WR_FLUSH_ERR)))
                mlx5_fpga_warn(conn->fdev, "RQ buf %p on FPGA QP %u completion status %d\n",
                               buf, conn->fpga_qpn, status);
        else
                mlx5_fpga_dbg(conn->fdev, "RQ buf %p on FPGA QP %u completion status %d\n",
                              buf, conn->fpga_qpn, status);

        mlx5_fpga_conn_unmap_buf(conn, buf);

        if (unlikely(status || !conn->qp.active)) {
                conn->qp.active = false;
                kfree(buf);
                return;
        }

        buf->sg[0].size = be32_to_cpu(cqe->byte_cnt);
        mlx5_fpga_dbg(conn->fdev, "Message with %u bytes received successfully\n",
                      buf->sg[0].size);
        conn->recv_cb(conn->cb_arg, buf);

        buf->sg[0].size = MLX5_FPGA_RECV_SIZE;
        err = mlx5_fpga_conn_post_recv(conn, buf);
        if (unlikely(err)) {
                mlx5_fpga_warn(conn->fdev,
                               "Failed to re-post recv buf: %d\n", err);
                kfree(buf);
        }
}

static void mlx5_fpga_conn_sq_cqe(struct mlx5_fpga_conn *conn,
                                  struct mlx5_cqe64 *cqe, u8 status)
{
        struct mlx5_fpga_dma_buf *buf, *nextbuf;
        unsigned long flags;
        int ix;

        spin_lock_irqsave(&conn->qp.sq.lock, flags);

        ix = be16_to_cpu(cqe->wqe_counter) & (conn->qp.sq.size - 1);
        buf = conn->qp.sq.bufs[ix];
        conn->qp.sq.bufs[ix] = NULL;
        conn->qp.sq.cc++;

        /* Handle backlog still under the spinlock to ensure message post order */
        if (unlikely(!list_empty(&conn->qp.sq.backlog))) {
                if (likely(conn->qp.active)) {
                        nextbuf = list_first_entry(&conn->qp.sq.backlog,
                                                   struct mlx5_fpga_dma_buf, list);
                        list_del(&nextbuf->list);
                        mlx5_fpga_conn_post_send(conn, nextbuf);
                }
        }

        spin_unlock_irqrestore(&conn->qp.sq.lock, flags);

        if (unlikely(status && (status != MLX5_CQE_SYNDROME_WR_FLUSH_ERR)))
                mlx5_fpga_warn(conn->fdev, "SQ buf %p on FPGA QP %u completion status %d\n",
                               buf, conn->fpga_qpn, status);
        else
                mlx5_fpga_dbg(conn->fdev, "SQ buf %p on FPGA QP %u completion status %d\n",
                              buf, conn->fpga_qpn, status);

        mlx5_fpga_conn_unmap_buf(conn, buf);

        if (likely(buf->complete))
                buf->complete(conn, conn->fdev, buf, status);

        if (unlikely(status))
                conn->qp.active = false;
}

static void mlx5_fpga_conn_handle_cqe(struct mlx5_fpga_conn *conn,
                                      struct mlx5_cqe64 *cqe)
{
        u8 opcode, status = 0;

        opcode = get_cqe_opcode(cqe);

        switch (opcode) {
        case MLX5_CQE_REQ_ERR:
                status = ((struct mlx5_err_cqe *)cqe)->syndrome;
                fallthrough;
        case MLX5_CQE_REQ:
                mlx5_fpga_conn_sq_cqe(conn, cqe, status);
                break;

        case MLX5_CQE_RESP_ERR:
                status = ((struct mlx5_err_cqe *)cqe)->syndrome;
                fallthrough;
        case MLX5_CQE_RESP_SEND:
                mlx5_fpga_conn_rq_cqe(conn, cqe, status);
                break;
        default:
                mlx5_fpga_warn(conn->fdev, "Unexpected cqe opcode %u\n",
                               opcode);
        }
}

static void mlx5_fpga_conn_arm_cq(struct mlx5_fpga_conn *conn)
{
        mlx5_cq_arm(&conn->cq.mcq, MLX5_CQ_DB_REQ_NOT,
                    conn->fdev->conn_res.uar->map, conn->cq.wq.cc);
}

static inline void mlx5_fpga_conn_cqes(struct mlx5_fpga_conn *conn,
                                       unsigned int budget)
{
        struct mlx5_cqe64 *cqe;

        while (budget) {
                cqe = mlx5_cqwq_get_cqe(&conn->cq.wq);
                if (!cqe)
                        break;

                budget--;
                mlx5_cqwq_pop(&conn->cq.wq);
                mlx5_fpga_conn_handle_cqe(conn, cqe);
                mlx5_cqwq_update_db_record(&conn->cq.wq);
        }
        if (!budget) {
                tasklet_schedule(&conn->cq.tasklet);
                return;
        }

        mlx5_fpga_dbg(conn->fdev, "Re-arming CQ with cc# %u\n", conn->cq.wq.cc);
        /* ensure cq space is freed before enabling more cqes */
        wmb();
        mlx5_fpga_conn_arm_cq(conn);
}

static void mlx5_fpga_conn_cq_tasklet(struct tasklet_struct *t)
{
        struct mlx5_fpga_conn *conn = from_tasklet(conn, t, cq.tasklet);

        if (unlikely(!conn->qp.active))
                return;
        mlx5_fpga_conn_cqes(conn, MLX5_FPGA_CQ_BUDGET);
}

static void mlx5_fpga_conn_cq_complete(struct mlx5_core_cq *mcq,
                                       struct mlx5_eqe *eqe)
{
        struct mlx5_fpga_conn *conn;

        conn = container_of(mcq, struct mlx5_fpga_conn, cq.mcq);
        if (unlikely(!conn->qp.active))
                return;
        mlx5_fpga_conn_cqes(conn, MLX5_FPGA_CQ_BUDGET);
}

static int mlx5_fpga_conn_create_cq(struct mlx5_fpga_conn *conn, int cq_size)
{
        struct mlx5_fpga_device *fdev = conn->fdev;
        struct mlx5_core_dev *mdev = fdev->mdev;
        u32 temp_cqc[MLX5_ST_SZ_DW(cqc)] = {0};
        u32 out[MLX5_ST_SZ_DW(create_cq_out)];
        struct mlx5_wq_param wqp;
        struct mlx5_cqe64 *cqe;
        int inlen, err, eqn;
        void *cqc, *in;
        __be64 *pas;
        u32 i;

        conn->cq.mcq.cqe_sz     = 64;
        conn->cq.mcq.set_ci_db  = conn->cq.wq_ctrl.db.db;
        conn->cq.mcq.arm_db     = conn->cq.wq_ctrl.db.db + 1;
        *conn->cq.mcq.set_ci_db = 0;
        conn->cq.mcq.vector     = 0;
        conn->cq.mcq.comp       = mlx5_fpga_conn_cq_complete;

        cq_size = roundup_pow_of_two(cq_size);
        MLX5_SET(cqc, temp_cqc, log_cq_size, ilog2(cq_size));

        wqp.buf_numa_node = mdev->priv.numa_node;
        wqp.db_numa_node  = mdev->priv.numa_node;

        err = mlx5_cqwq_create(mdev, &wqp, temp_cqc, &conn->cq.wq,
                               &conn->cq.wq_ctrl);
        if (err)
                return err;

        for (i = 0; i < mlx5_cqwq_get_size(&conn->cq.wq); i++) {
                cqe = mlx5_cqwq_get_wqe(&conn->cq.wq, i);
                cqe->op_own = MLX5_CQE_INVALID << 4 | MLX5_CQE_OWNER_MASK;
        }

        inlen = MLX5_ST_SZ_BYTES(create_cq_in) +
                sizeof(u64) * conn->cq.wq_ctrl.buf.npages;
        in = kvzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_cqwq;
        }

        err = mlx5_comp_eqn_get(mdev, smp_processor_id(), &eqn);
        if (err) {
                kvfree(in);
                goto err_cqwq;
        }

        cqc = MLX5_ADDR_OF(create_cq_in, in, cq_context);
        MLX5_SET(cqc, cqc, log_cq_size, ilog2(cq_size));
        MLX5_SET(cqc, cqc, c_eqn_or_apu_element, eqn);
        MLX5_SET(cqc, cqc, uar_page, fdev->conn_res.uar->index);
        MLX5_SET(cqc, cqc, log_page_size, conn->cq.wq_ctrl.buf.page_shift -
                           MLX5_ADAPTER_PAGE_SHIFT);
        MLX5_SET64(cqc, cqc, dbr_addr, conn->cq.wq_ctrl.db.dma);

        pas = (__be64 *)MLX5_ADDR_OF(create_cq_in, in, pas);
        mlx5_fill_page_frag_array(&conn->cq.wq_ctrl.buf, pas);

        err = mlx5_core_create_cq(mdev, &conn->cq.mcq, in, inlen, out, sizeof(out));
        kvfree(in);

        if (err)
                goto err_cqwq;

        tasklet_setup(&conn->cq.tasklet, mlx5_fpga_conn_cq_tasklet);
        mlx5_fpga_dbg(fdev, "Created CQ #0x%x\n", conn->cq.mcq.cqn);

        goto out;

err_cqwq:
        mlx5_wq_destroy(&conn->cq.wq_ctrl);
out:
        return err;
}

static void mlx5_fpga_conn_destroy_cq(struct mlx5_fpga_conn *conn)
{
        tasklet_disable(&conn->cq.tasklet);
        tasklet_kill(&conn->cq.tasklet);
        mlx5_core_destroy_cq(conn->fdev->mdev, &conn->cq.mcq);
        mlx5_wq_destroy(&conn->cq.wq_ctrl);
}

static int mlx5_fpga_conn_create_wq(struct mlx5_fpga_conn *conn, void *qpc)
{
        struct mlx5_fpga_device *fdev = conn->fdev;
        struct mlx5_core_dev *mdev = fdev->mdev;
        struct mlx5_wq_param wqp;

        wqp.buf_numa_node = mdev->priv.numa_node;
        wqp.db_numa_node  = mdev->priv.numa_node;

        return mlx5_wq_qp_create(mdev, &wqp, qpc, &conn->qp.wq,
                                 &conn->qp.wq_ctrl);
}

static int mlx5_fpga_conn_create_qp(struct mlx5_fpga_conn *conn,
                                    unsigned int tx_size, unsigned int rx_size)
{
        struct mlx5_fpga_device *fdev = conn->fdev;
        u32 out[MLX5_ST_SZ_DW(create_qp_out)] = {};
        struct mlx5_core_dev *mdev = fdev->mdev;
        u32 temp_qpc[MLX5_ST_SZ_DW(qpc)] = {};
        void *in = NULL, *qpc;
        int err, inlen;

        conn->qp.rq.pc = 0;
        conn->qp.rq.cc = 0;
        conn->qp.rq.size = roundup_pow_of_two(rx_size);
        conn->qp.sq.pc = 0;
        conn->qp.sq.cc = 0;
        conn->qp.sq.size = roundup_pow_of_two(tx_size);

        MLX5_SET(qpc, temp_qpc, log_rq_stride, ilog2(MLX5_SEND_WQE_DS) - 4);
        MLX5_SET(qpc, temp_qpc, log_rq_size, ilog2(conn->qp.rq.size));
        MLX5_SET(qpc, temp_qpc, log_sq_size, ilog2(conn->qp.sq.size));
        err = mlx5_fpga_conn_create_wq(conn, temp_qpc);
        if (err)
                goto out;

        conn->qp.rq.bufs = kvzalloc_objs(conn->qp.rq.bufs[0], conn->qp.rq.size);
        if (!conn->qp.rq.bufs) {
                err = -ENOMEM;
                goto err_wq;
        }

        conn->qp.sq.bufs = kvzalloc_objs(conn->qp.sq.bufs[0], conn->qp.sq.size);
        if (!conn->qp.sq.bufs) {
                err = -ENOMEM;
                goto err_rq_bufs;
        }

        inlen = MLX5_ST_SZ_BYTES(create_qp_in) +
                MLX5_FLD_SZ_BYTES(create_qp_in, pas[0]) *
                conn->qp.wq_ctrl.buf.npages;
        in = kvzalloc(inlen, GFP_KERNEL);
        if (!in) {
                err = -ENOMEM;
                goto err_sq_bufs;
        }

        qpc = MLX5_ADDR_OF(create_qp_in, in, qpc);
        MLX5_SET(qpc, qpc, uar_page, fdev->conn_res.uar->index);
        MLX5_SET(qpc, qpc, log_page_size,
                 conn->qp.wq_ctrl.buf.page_shift - MLX5_ADAPTER_PAGE_SHIFT);
        MLX5_SET(qpc, qpc, fre, 1);
        MLX5_SET(qpc, qpc, rlky, 1);
        MLX5_SET(qpc, qpc, st, MLX5_QP_ST_RC);
        MLX5_SET(qpc, qpc, pm_state, MLX5_QP_PM_MIGRATED);
        MLX5_SET(qpc, qpc, pd, fdev->conn_res.pdn);
        MLX5_SET(qpc, qpc, log_rq_stride, ilog2(MLX5_SEND_WQE_DS) - 4);
        MLX5_SET(qpc, qpc, log_rq_size, ilog2(conn->qp.rq.size));
        MLX5_SET(qpc, qpc, rq_type, MLX5_NON_ZERO_RQ);
        MLX5_SET(qpc, qpc, log_sq_size, ilog2(conn->qp.sq.size));
        MLX5_SET(qpc, qpc, cqn_snd, conn->cq.mcq.cqn);
        MLX5_SET(qpc, qpc, cqn_rcv, conn->cq.mcq.cqn);
        MLX5_SET(qpc, qpc, ts_format, mlx5_get_qp_default_ts(mdev));
        MLX5_SET64(qpc, qpc, dbr_addr, conn->qp.wq_ctrl.db.dma);
        if (MLX5_CAP_GEN(mdev, cqe_version) == 1)
                MLX5_SET(qpc, qpc, user_index, 0xFFFFFF);

        mlx5_fill_page_frag_array(&conn->qp.wq_ctrl.buf,
                                  (__be64 *)MLX5_ADDR_OF(create_qp_in, in, pas));

        MLX5_SET(create_qp_in, in, opcode, MLX5_CMD_OP_CREATE_QP);
        err = mlx5_cmd_exec(mdev, in, inlen, out, sizeof(out));
        if (err)
                goto err_sq_bufs;

        conn->qp.qpn = MLX5_GET(create_qp_out, out, qpn);
        mlx5_fpga_dbg(fdev, "Created QP #0x%x\n", conn->qp.qpn);

        goto out;

err_sq_bufs:
        kvfree(conn->qp.sq.bufs);
err_rq_bufs:
        kvfree(conn->qp.rq.bufs);
err_wq:
        mlx5_wq_destroy(&conn->qp.wq_ctrl);
out:
        kvfree(in);
        return err;
}

static void mlx5_fpga_conn_free_recv_bufs(struct mlx5_fpga_conn *conn)
{
        int ix;

        for (ix = 0; ix < conn->qp.rq.size; ix++) {
                if (!conn->qp.rq.bufs[ix])
                        continue;
                mlx5_fpga_conn_unmap_buf(conn, conn->qp.rq.bufs[ix]);
                kfree(conn->qp.rq.bufs[ix]);
                conn->qp.rq.bufs[ix] = NULL;
        }
}

static void mlx5_fpga_conn_flush_send_bufs(struct mlx5_fpga_conn *conn)
{
        struct mlx5_fpga_dma_buf *buf, *temp;
        int ix;

        for (ix = 0; ix < conn->qp.sq.size; ix++) {
                buf = conn->qp.sq.bufs[ix];
                if (!buf)
                        continue;
                conn->qp.sq.bufs[ix] = NULL;
                mlx5_fpga_conn_unmap_buf(conn, buf);
                if (!buf->complete)
                        continue;
                buf->complete(conn, conn->fdev, buf, MLX5_CQE_SYNDROME_WR_FLUSH_ERR);
        }
        list_for_each_entry_safe(buf, temp, &conn->qp.sq.backlog, list) {
                mlx5_fpga_conn_unmap_buf(conn, buf);
                if (!buf->complete)
                        continue;
                buf->complete(conn, conn->fdev, buf, MLX5_CQE_SYNDROME_WR_FLUSH_ERR);
        }
}

static void mlx5_fpga_conn_destroy_qp(struct mlx5_fpga_conn *conn)
{
        struct mlx5_core_dev *dev = conn->fdev->mdev;
        u32 in[MLX5_ST_SZ_DW(destroy_qp_in)] = {};

        MLX5_SET(destroy_qp_in, in, opcode, MLX5_CMD_OP_DESTROY_QP);
        MLX5_SET(destroy_qp_in, in, qpn, conn->qp.qpn);
        mlx5_cmd_exec_in(dev, destroy_qp, in);

        mlx5_fpga_conn_free_recv_bufs(conn);
        mlx5_fpga_conn_flush_send_bufs(conn);
        kvfree(conn->qp.sq.bufs);
        kvfree(conn->qp.rq.bufs);
        mlx5_wq_destroy(&conn->qp.wq_ctrl);
}

static int mlx5_fpga_conn_reset_qp(struct mlx5_fpga_conn *conn)
{
        struct mlx5_core_dev *mdev = conn->fdev->mdev;
        u32 in[MLX5_ST_SZ_DW(qp_2rst_in)] = {};

        mlx5_fpga_dbg(conn->fdev, "Modifying QP %u to RST\n", conn->qp.qpn);

        MLX5_SET(qp_2rst_in, in, opcode, MLX5_CMD_OP_2RST_QP);
        MLX5_SET(qp_2rst_in, in, qpn, conn->qp.qpn);

        return mlx5_cmd_exec_in(mdev, qp_2rst, in);
}

static int mlx5_fpga_conn_init_qp(struct mlx5_fpga_conn *conn)
{
        u32 in[MLX5_ST_SZ_DW(rst2init_qp_in)] = {};
        struct mlx5_fpga_device *fdev = conn->fdev;
        struct mlx5_core_dev *mdev = fdev->mdev;
        u32 *qpc;

        mlx5_fpga_dbg(conn->fdev, "Modifying QP %u to INIT\n", conn->qp.qpn);

        qpc = MLX5_ADDR_OF(rst2init_qp_in, in, qpc);

        MLX5_SET(qpc, qpc, st, MLX5_QP_ST_RC);
        MLX5_SET(qpc, qpc, pm_state, MLX5_QP_PM_MIGRATED);
        MLX5_SET(qpc, qpc, primary_address_path.pkey_index, MLX5_FPGA_PKEY_INDEX);
        MLX5_SET(qpc, qpc, primary_address_path.vhca_port_num, MLX5_FPGA_PORT_NUM);
        MLX5_SET(qpc, qpc, pd, conn->fdev->conn_res.pdn);
        MLX5_SET(qpc, qpc, cqn_snd, conn->cq.mcq.cqn);
        MLX5_SET(qpc, qpc, cqn_rcv, conn->cq.mcq.cqn);
        MLX5_SET64(qpc, qpc, dbr_addr, conn->qp.wq_ctrl.db.dma);

        MLX5_SET(rst2init_qp_in, in, opcode, MLX5_CMD_OP_RST2INIT_QP);
        MLX5_SET(rst2init_qp_in, in, qpn, conn->qp.qpn);

        return mlx5_cmd_exec_in(mdev, rst2init_qp, in);
}

static int mlx5_fpga_conn_rtr_qp(struct mlx5_fpga_conn *conn)
{
        u32 in[MLX5_ST_SZ_DW(init2rtr_qp_in)] = {};
        struct mlx5_fpga_device *fdev = conn->fdev;
        struct mlx5_core_dev *mdev = fdev->mdev;
        u32 *qpc;

        mlx5_fpga_dbg(conn->fdev, "QP RTR\n");

        qpc = MLX5_ADDR_OF(init2rtr_qp_in, in, qpc);

        MLX5_SET(qpc, qpc, mtu, MLX5_QPC_MTU_1K_BYTES);
        MLX5_SET(qpc, qpc, log_msg_max, (u8)MLX5_CAP_GEN(mdev, log_max_msg));
        MLX5_SET(qpc, qpc, remote_qpn, conn->fpga_qpn);
        MLX5_SET(qpc, qpc, next_rcv_psn,
                 MLX5_GET(fpga_qpc, conn->fpga_qpc, next_send_psn));
        MLX5_SET(qpc, qpc, primary_address_path.pkey_index, MLX5_FPGA_PKEY_INDEX);
        MLX5_SET(qpc, qpc, primary_address_path.vhca_port_num, MLX5_FPGA_PORT_NUM);
        ether_addr_copy(MLX5_ADDR_OF(qpc, qpc, primary_address_path.rmac_47_32),
                        MLX5_ADDR_OF(fpga_qpc, conn->fpga_qpc, fpga_mac_47_32));
        MLX5_SET(qpc, qpc, primary_address_path.udp_sport,
                 MLX5_CAP_ROCE(mdev, r_roce_min_src_udp_port));
        MLX5_SET(qpc, qpc, primary_address_path.src_addr_index,
                 conn->qp.sgid_index);
        MLX5_SET(qpc, qpc, primary_address_path.hop_limit, 0);
        memcpy(MLX5_ADDR_OF(qpc, qpc, primary_address_path.rgid_rip),
               MLX5_ADDR_OF(fpga_qpc, conn->fpga_qpc, fpga_ip),
               MLX5_FLD_SZ_BYTES(qpc, primary_address_path.rgid_rip));

        MLX5_SET(init2rtr_qp_in, in, opcode, MLX5_CMD_OP_INIT2RTR_QP);
        MLX5_SET(init2rtr_qp_in, in, qpn, conn->qp.qpn);

        return mlx5_cmd_exec_in(mdev, init2rtr_qp, in);
}

static int mlx5_fpga_conn_rts_qp(struct mlx5_fpga_conn *conn)
{
        struct mlx5_fpga_device *fdev = conn->fdev;
        u32 in[MLX5_ST_SZ_DW(rtr2rts_qp_in)] = {};
        struct mlx5_core_dev *mdev = fdev->mdev;
        u32 *qpc;

        mlx5_fpga_dbg(conn->fdev, "QP RTS\n");

        qpc = MLX5_ADDR_OF(rtr2rts_qp_in, in, qpc);

        MLX5_SET(qpc, qpc, log_ack_req_freq, 8);
        MLX5_SET(qpc, qpc, min_rnr_nak, 0x12);
        MLX5_SET(qpc, qpc, primary_address_path.ack_timeout, 0x12); /* ~1.07s */
        MLX5_SET(qpc, qpc, next_send_psn,
                 MLX5_GET(fpga_qpc, conn->fpga_qpc, next_rcv_psn));
        MLX5_SET(qpc, qpc, retry_count, 7);
        MLX5_SET(qpc, qpc, rnr_retry, 7); /* Infinite retry if RNR NACK */

        MLX5_SET(rtr2rts_qp_in, in, opcode, MLX5_CMD_OP_RTR2RTS_QP);
        MLX5_SET(rtr2rts_qp_in, in, qpn, conn->qp.qpn);
        MLX5_SET(rtr2rts_qp_in, in, opt_param_mask, MLX5_QP_OPTPAR_RNR_TIMEOUT);

        return mlx5_cmd_exec_in(mdev, rtr2rts_qp, in);
}

static int mlx5_fpga_conn_connect(struct mlx5_fpga_conn *conn)
{
        struct mlx5_fpga_device *fdev = conn->fdev;
        int err;

        MLX5_SET(fpga_qpc, conn->fpga_qpc, state, MLX5_FPGA_QPC_STATE_ACTIVE);
        err = mlx5_fpga_modify_qp(conn->fdev->mdev, conn->fpga_qpn,
                                  MLX5_FPGA_QPC_STATE, &conn->fpga_qpc);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to activate FPGA RC QP: %d\n", err);
                goto out;
        }

        err = mlx5_fpga_conn_reset_qp(conn);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to change QP state to reset\n");
                goto err_fpga_qp;
        }

        err = mlx5_fpga_conn_init_qp(conn);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to modify QP from RESET to INIT\n");
                goto err_fpga_qp;
        }
        conn->qp.active = true;

        while (!mlx5_fpga_conn_post_recv_buf(conn))
                ;

        err = mlx5_fpga_conn_rtr_qp(conn);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to change QP state from INIT to RTR\n");
                goto err_recv_bufs;
        }

        err = mlx5_fpga_conn_rts_qp(conn);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to change QP state from RTR to RTS\n");
                goto err_recv_bufs;
        }
        goto out;

err_recv_bufs:
        mlx5_fpga_conn_free_recv_bufs(conn);
err_fpga_qp:
        MLX5_SET(fpga_qpc, conn->fpga_qpc, state, MLX5_FPGA_QPC_STATE_INIT);
        if (mlx5_fpga_modify_qp(conn->fdev->mdev, conn->fpga_qpn,
                                MLX5_FPGA_QPC_STATE, &conn->fpga_qpc))
                mlx5_fpga_err(fdev, "Failed to revert FPGA QP to INIT\n");
out:
        return err;
}

struct mlx5_fpga_conn *mlx5_fpga_conn_create(struct mlx5_fpga_device *fdev,
                                             struct mlx5_fpga_conn_attr *attr,
                                             enum mlx5_ifc_fpga_qp_type qp_type)
{
        struct mlx5_fpga_conn *ret, *conn;
        u8 *remote_mac, *remote_ip;
        int err;

        if (!attr->recv_cb)
                return ERR_PTR(-EINVAL);

        conn = kzalloc_obj(*conn);
        if (!conn)
                return ERR_PTR(-ENOMEM);

        conn->fdev = fdev;
        INIT_LIST_HEAD(&conn->qp.sq.backlog);

        spin_lock_init(&conn->qp.sq.lock);

        conn->recv_cb = attr->recv_cb;
        conn->cb_arg = attr->cb_arg;

        remote_mac = MLX5_ADDR_OF(fpga_qpc, conn->fpga_qpc, remote_mac_47_32);
        err = mlx5_query_mac_address(fdev->mdev, remote_mac);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to query local MAC: %d\n", err);
                ret = ERR_PTR(err);
                goto err;
        }

        /* Build Modified EUI-64 IPv6 address from the MAC address */
        remote_ip = MLX5_ADDR_OF(fpga_qpc, conn->fpga_qpc, remote_ip);
        remote_ip[0] = 0xfe;
        remote_ip[1] = 0x80;
        addrconf_addr_eui48(&remote_ip[8], remote_mac);

        err = mlx5_core_reserved_gid_alloc(fdev->mdev, &conn->qp.sgid_index);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to allocate SGID: %d\n", err);
                ret = ERR_PTR(err);
                goto err;
        }

        err = mlx5_core_roce_gid_set(fdev->mdev, conn->qp.sgid_index,
                                     MLX5_ROCE_VERSION_2,
                                     MLX5_ROCE_L3_TYPE_IPV6,
                                     remote_ip, remote_mac, true, 0,
                                     MLX5_FPGA_PORT_NUM);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to set SGID: %d\n", err);
                ret = ERR_PTR(err);
                goto err_rsvd_gid;
        }
        mlx5_fpga_dbg(fdev, "Reserved SGID index %u\n", conn->qp.sgid_index);

        /* Allow for one cqe per rx/tx wqe, plus one cqe for the next wqe,
         * created during processing of the cqe
         */
        err = mlx5_fpga_conn_create_cq(conn,
                                       (attr->tx_size + attr->rx_size) * 2);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to create CQ: %d\n", err);
                ret = ERR_PTR(err);
                goto err_gid;
        }

        mlx5_fpga_conn_arm_cq(conn);

        err = mlx5_fpga_conn_create_qp(conn, attr->tx_size, attr->rx_size);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to create QP: %d\n", err);
                ret = ERR_PTR(err);
                goto err_cq;
        }

        MLX5_SET(fpga_qpc, conn->fpga_qpc, state, MLX5_FPGA_QPC_STATE_INIT);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, qp_type, qp_type);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, st, MLX5_FPGA_QPC_ST_RC);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, ether_type, ETH_P_8021Q);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, vid, 0);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, next_rcv_psn, 1);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, next_send_psn, 0);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, pkey, MLX5_FPGA_PKEY);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, remote_qpn, conn->qp.qpn);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, rnr_retry, 7);
        MLX5_SET(fpga_qpc, conn->fpga_qpc, retry_count, 7);

        err = mlx5_fpga_create_qp(fdev->mdev, &conn->fpga_qpc,
                                  &conn->fpga_qpn);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to create FPGA RC QP: %d\n", err);
                ret = ERR_PTR(err);
                goto err_qp;
        }

        err = mlx5_fpga_conn_connect(conn);
        if (err) {
                ret = ERR_PTR(err);
                goto err_conn;
        }

        mlx5_fpga_dbg(fdev, "FPGA QPN is %u\n", conn->fpga_qpn);
        ret = conn;
        goto out;

err_conn:
        mlx5_fpga_destroy_qp(conn->fdev->mdev, conn->fpga_qpn);
err_qp:
        mlx5_fpga_conn_destroy_qp(conn);
err_cq:
        mlx5_fpga_conn_destroy_cq(conn);
err_gid:
        mlx5_core_roce_gid_set(fdev->mdev, conn->qp.sgid_index, 0, 0, NULL,
                               NULL, false, 0, MLX5_FPGA_PORT_NUM);
err_rsvd_gid:
        mlx5_core_reserved_gid_free(fdev->mdev, conn->qp.sgid_index);
err:
        kfree(conn);
out:
        return ret;
}

void mlx5_fpga_conn_destroy(struct mlx5_fpga_conn *conn)
{
        conn->qp.active = false;
        tasklet_disable(&conn->cq.tasklet);
        synchronize_irq(conn->cq.mcq.irqn);

        mlx5_fpga_destroy_qp(conn->fdev->mdev, conn->fpga_qpn);
        mlx5_fpga_conn_destroy_qp(conn);
        mlx5_fpga_conn_destroy_cq(conn);

        mlx5_core_roce_gid_set(conn->fdev->mdev, conn->qp.sgid_index, 0, 0,
                               NULL, NULL, false, 0, MLX5_FPGA_PORT_NUM);
        mlx5_core_reserved_gid_free(conn->fdev->mdev, conn->qp.sgid_index);
        kfree(conn);
}

int mlx5_fpga_conn_device_init(struct mlx5_fpga_device *fdev)
{
        int err;

        err = mlx5_nic_vport_enable_roce(fdev->mdev);
        if (err) {
                mlx5_fpga_err(fdev, "Failed to enable RoCE: %d\n", err);
                goto out;
        }

        fdev->conn_res.uar = mlx5_get_uars_page(fdev->mdev);
        if (IS_ERR(fdev->conn_res.uar)) {
                err = PTR_ERR(fdev->conn_res.uar);
                mlx5_fpga_err(fdev, "get_uars_page failed, %d\n", err);
                goto err_roce;
        }
        mlx5_fpga_dbg(fdev, "Allocated UAR index %u\n",
                      fdev->conn_res.uar->index);

        err = mlx5_core_alloc_pd(fdev->mdev, &fdev->conn_res.pdn);
        if (err) {
                mlx5_fpga_err(fdev, "alloc pd failed, %d\n", err);
                goto err_uar;
        }
        mlx5_fpga_dbg(fdev, "Allocated PD %u\n", fdev->conn_res.pdn);

        err = mlx5_fpga_conn_create_mkey(fdev->mdev, fdev->conn_res.pdn,
                                         &fdev->conn_res.mkey);
        if (err) {
                mlx5_fpga_err(fdev, "create mkey failed, %d\n", err);
                goto err_dealloc_pd;
        }
        mlx5_fpga_dbg(fdev, "Created mkey 0x%x\n", fdev->conn_res.mkey);

        return 0;

err_dealloc_pd:
        mlx5_core_dealloc_pd(fdev->mdev, fdev->conn_res.pdn);
err_uar:
        mlx5_put_uars_page(fdev->mdev, fdev->conn_res.uar);
err_roce:
        mlx5_nic_vport_disable_roce(fdev->mdev);
out:
        return err;
}

void mlx5_fpga_conn_device_cleanup(struct mlx5_fpga_device *fdev)
{
        mlx5_core_destroy_mkey(fdev->mdev, fdev->conn_res.mkey);
        mlx5_core_dealloc_pd(fdev->mdev, fdev->conn_res.pdn);
        mlx5_put_uars_page(fdev->mdev, fdev->conn_res.uar);
        mlx5_nic_vport_disable_roce(fdev->mdev);
}