/*
 *   BSD LICENSE
 *
 *   Copyright(c) 2017 Cavium, Inc.. All rights reserved.
 *   All rights reserved.
 *
 *   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.
 *     * Neither the name of Cavium, Inc. nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "lio_bsd.h"
#include "lio_common.h"
#include "lio_droq.h"
#include "lio_iq.h"
#include "lio_response_manager.h"
#include "lio_device.h"
#include "lio_main.h"

static void     lio_poll_req_completion(void *arg, int pending);

int
lio_setup_response_list(struct octeon_device *oct)
{
        struct lio_tq   *ctq;
        int             i, ret = 0;

        for (i = 0; i < LIO_MAX_RESPONSE_LISTS; i++) {
                STAILQ_INIT(&oct->response_list[i].head);
                mtx_init(&oct->response_list[i].lock, "response_list_lock",
                         NULL, MTX_DEF);
                atomic_store_rel_int(&oct->response_list[i].pending_req_count,
                                     0);
        }
        mtx_init(&oct->cmd_resp_wqlock, "cmd_resp_wqlock", NULL, MTX_DEF);

        ctq = &oct->dma_comp_tq;
        ctq->tq = taskqueue_create("lio_dma_comp", M_WAITOK,
                                   taskqueue_thread_enqueue, &ctq->tq);

        TIMEOUT_TASK_INIT(ctq->tq, &ctq->work, 0, lio_poll_req_completion,
                          (void *)ctq);
        ctq->ctxptr = oct;

        oct->cmd_resp_state = LIO_DRV_ONLINE;
        taskqueue_start_threads(&ctq->tq, 1, PI_NET, "lio%d_dma_comp",
                                oct->octeon_id);
        taskqueue_enqueue_timeout(ctq->tq, &ctq->work, lio_ms_to_ticks(50));

        return (ret);
}

void
lio_delete_response_list(struct octeon_device *oct)
{

        if (oct->dma_comp_tq.tq != NULL) {
                while (taskqueue_cancel_timeout(oct->dma_comp_tq.tq,
                                                &oct->dma_comp_tq.work, NULL))
                        taskqueue_drain_timeout(oct->dma_comp_tq.tq,
                                                &oct->dma_comp_tq.work);
                taskqueue_free(oct->dma_comp_tq.tq);
                oct->dma_comp_tq.tq = NULL;
        }
}

int
lio_process_ordered_list(struct octeon_device *octeon_dev,
                         uint32_t force_quit)
{
        struct lio_response_list        *ordered_sc_list;
        struct lio_soft_command         *sc;
        uint64_t                        status64;
        uint32_t                        status;
        int                             request_complete = 0;
        int                             resp_to_process;

        resp_to_process = LIO_MAX_ORD_REQS_TO_PROCESS;

        ordered_sc_list = &octeon_dev->response_list[LIO_ORDERED_SC_LIST];

        do {
                mtx_lock(&ordered_sc_list->lock);

                if (STAILQ_EMPTY(&ordered_sc_list->head)) {
                        /*
                         * ordered_sc_list is empty; there is nothing to
                         * process
                         */
                        mtx_unlock(&ordered_sc_list->lock);
                        return (1);
                }

                sc = LIO_STAILQ_FIRST_ENTRY(&ordered_sc_list->head,
                                            struct lio_soft_command, node);

                status = LIO_REQUEST_PENDING;

                /*
                 * check if octeon has finished DMA'ing a response to where
                 * rptr is pointing to
                 */
                status64 = *sc->status_word;

                if (status64 != COMPLETION_WORD_INIT) {
                        /*
                         * This logic ensures that all 64b have been written.
                         * 1. check byte 0 for non-FF
                         * 2. if non-FF, then swap result from BE to host order
                         * 3. check byte 7 (swapped to 0) for non-FF
                         * 4. if non-FF, use the low 32-bit status code
                         * 5. if either byte 0 or byte 7 is FF, don't use status
                         */
                        if ((status64 & 0xff) != 0xff) {
                                lio_swap_8B_data(&status64, 1);
                                if (((status64 & 0xff) != 0xff)) {
                                        /* retrieve 16-bit firmware status */
                                        status = (uint32_t)(status64 &
                                                            0xffffULL);
                                        if (status) {
                                                status = LIO_FW_STATUS_CODE(
                                                                        status);
                                        } else {
                                                /* i.e. no error */
                                                status = LIO_REQUEST_DONE;
                                        }
                                }
                        }
                } else if (force_quit || (sc->timeout &&
                           lio_check_timeout(ticks, sc->timeout))) {
                        lio_dev_err(octeon_dev, "%s: cmd failed, timeout (%u, %u)\n",
                                    __func__, ticks, sc->timeout);
                        status = LIO_REQUEST_TIMEOUT;
                }

                if (status != LIO_REQUEST_PENDING) {
                        /* we have received a response or we have timed out */
                        /* remove node from linked list */
                        STAILQ_REMOVE(&octeon_dev->response_list
                                      [LIO_ORDERED_SC_LIST].head,
                                      &sc->node, lio_stailq_node, entries);
                        atomic_subtract_int(&octeon_dev->response_list
                                            [LIO_ORDERED_SC_LIST].
                                            pending_req_count, 1);
                        mtx_unlock(&ordered_sc_list->lock);

                        if (sc->callback != NULL)
                                sc->callback(octeon_dev, status,
                                             sc->callback_arg);

                        request_complete++;

                } else {
                        /* no response yet */
                        request_complete = 0;
                        mtx_unlock(&ordered_sc_list->lock);
                }

                /*
                 * If we hit the Max Ordered requests to process every loop,
                 * we quit and let this function be invoked the next time
                 * the poll thread runs to process the remaining requests.
                 * This function can take up the entire CPU if there is no
                 * upper limit to the requests processed.
                 */
                if (request_complete >= resp_to_process)
                        break;
        } while (request_complete);

        return (0);
}

static void
lio_poll_req_completion(void *arg, int pending)
{
        struct lio_tq           *ctq = (struct lio_tq *)arg;
        struct octeon_device    *oct = (struct octeon_device *)ctq->ctxptr;

        lio_process_ordered_list(oct, 0);
        taskqueue_enqueue_timeout(ctq->tq, &ctq->work, lio_ms_to_ticks(50));
}