/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2010-2016 Solarflare Communications Inc.
 * All rights reserved.
 *
 * This software was developed in part by Philip Paeps under contract for
 * Solarflare Communications, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * 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 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.
 *
 * The views and conclusions contained in the software and documentation are
 * those of the authors and should not be interpreted as representing official
 * policies, either expressed or implied, of the FreeBSD Project.
 */

#include <sys/param.h>
#include <sys/condvar.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/syslog.h>
#include <sys/taskqueue.h>
#include <sys/malloc.h>

#include "common/efx.h"
#include "common/efx_mcdi.h"
#include "common/efx_regs_mcdi.h"

#include "sfxge.h"

#if EFSYS_OPT_MCDI_LOGGING
#include <dev/pci/pcivar.h>
#endif

#define SFXGE_MCDI_POLL_INTERVAL_MIN 10         /* 10us in 1us units */
#define SFXGE_MCDI_POLL_INTERVAL_MAX 100000     /* 100ms in 1us units */

static void
sfxge_mcdi_timeout(struct sfxge_softc *sc)
{
        device_t dev = sc->dev;

        log(LOG_WARNING, "[%s%d] MC_TIMEOUT", device_get_name(dev),
                device_get_unit(dev));

        EFSYS_PROBE(mcdi_timeout);
        sfxge_schedule_reset(sc);
}

static void
sfxge_mcdi_poll(struct sfxge_softc *sc, uint32_t timeout_us)
{
        efx_nic_t *enp;
        clock_t delay_total;
        clock_t delay_us;
        boolean_t aborted __diagused;

        delay_total = 0;
        delay_us = SFXGE_MCDI_POLL_INTERVAL_MIN;
        enp = sc->enp;

        do {
                if (efx_mcdi_request_poll(enp)) {
                        EFSYS_PROBE1(mcdi_delay, clock_t, delay_total);
                        return;
                }

                if (delay_total > timeout_us) {
                        aborted = efx_mcdi_request_abort(enp);
                        KASSERT(aborted, ("abort failed"));
                        sfxge_mcdi_timeout(sc);
                        return;
                }

                /* Spin or block depending on delay interval. */
                if (delay_us < 1000000)
                        DELAY(delay_us);
                else
                        pause("mcdi wait", delay_us * hz / 1000000);

                delay_total += delay_us;

                /* Exponentially back off the poll frequency. */
                delay_us = delay_us * 2;
                if (delay_us > SFXGE_MCDI_POLL_INTERVAL_MAX)
                        delay_us = SFXGE_MCDI_POLL_INTERVAL_MAX;

        } while (1);
}

static void
sfxge_mcdi_execute(void *arg, efx_mcdi_req_t *emrp)
{
        struct sfxge_softc *sc;
        struct sfxge_mcdi *mcdi;
        uint32_t timeout_us = 0;

        sc = (struct sfxge_softc *)arg;
        mcdi = &sc->mcdi;

        SFXGE_MCDI_LOCK(mcdi);

        KASSERT(mcdi->state == SFXGE_MCDI_INITIALIZED,
            ("MCDI not initialized"));

        /* Issue request and poll for completion. */
        efx_mcdi_get_timeout(sc->enp, emrp, &timeout_us);
        KASSERT(timeout_us > 0, ("MCDI timeout not initialized"));

        efx_mcdi_request_start(sc->enp, emrp, B_FALSE);
        sfxge_mcdi_poll(sc, timeout_us);

        SFXGE_MCDI_UNLOCK(mcdi);
}

static void
sfxge_mcdi_ev_cpl(void *arg)
{
        struct sfxge_softc *sc;
        struct sfxge_mcdi *mcdi __diagused;

        sc = (struct sfxge_softc *)arg;
        mcdi = &sc->mcdi;

        KASSERT(mcdi->state == SFXGE_MCDI_INITIALIZED,
            ("MCDI not initialized"));

        /* We do not use MCDI completion, MCDI is simply polled */
}

static void
sfxge_mcdi_exception(void *arg, efx_mcdi_exception_t eme)
{
        struct sfxge_softc *sc;
        device_t dev;

        sc = (struct sfxge_softc *)arg;
        dev = sc->dev;

        log(LOG_WARNING, "[%s%d] MC_%s", device_get_name(dev),
            device_get_unit(dev),
            (eme == EFX_MCDI_EXCEPTION_MC_REBOOT)
            ? "REBOOT"
            : (eme == EFX_MCDI_EXCEPTION_MC_BADASSERT)
            ? "BADASSERT" : "UNKNOWN");

        EFSYS_PROBE(mcdi_exception);

        sfxge_schedule_reset(sc);
}

#if EFSYS_OPT_MCDI_LOGGING

#define SFXGE_MCDI_LOG_BUF_SIZE 128

static size_t
sfxge_mcdi_do_log(char *buffer, void *data, size_t data_size,
                  size_t pfxsize, size_t position)
{
        uint32_t *words = data;
        size_t i;

        for (i = 0; i < data_size; i += sizeof(*words)) {
                if (position + 2 * sizeof(*words) + 1 >= SFXGE_MCDI_LOG_BUF_SIZE) {
                        buffer[position] = '\0';
                        printf("%s \\\n", buffer);
                        position = pfxsize;
                }
                snprintf(buffer + position, SFXGE_MCDI_LOG_BUF_SIZE - position,
                         " %08x", *words);
                words++;
                position += 2 * sizeof(uint32_t) + 1;
        }
        return (position);
}

static void
sfxge_mcdi_logger(void *arg, efx_log_msg_t type,
                  void *header, size_t header_size,
                  void *data, size_t data_size)
{
        struct sfxge_softc *sc = (struct sfxge_softc *)arg;
        char buffer[SFXGE_MCDI_LOG_BUF_SIZE];
        size_t pfxsize;
        size_t start;

        if (!sc->mcdi_logging)
                return;

        pfxsize = snprintf(buffer, sizeof(buffer),
                           "sfc %04x:%02x:%02x.%02x %s MCDI RPC %s:",
                           pci_get_domain(sc->dev),
                           pci_get_bus(sc->dev),
                           pci_get_slot(sc->dev),
                           pci_get_function(sc->dev),
                           device_get_nameunit(sc->dev),
                           type == EFX_LOG_MCDI_REQUEST ? "REQ" :
                           type == EFX_LOG_MCDI_RESPONSE ? "RESP" : "???");
        start = sfxge_mcdi_do_log(buffer, header, header_size,
                                  pfxsize, pfxsize);
        start = sfxge_mcdi_do_log(buffer, data, data_size, pfxsize, start);
        if (start != pfxsize) {
                buffer[start] = '\0';
                printf("%s\n", buffer);
        }
}

#endif

int
sfxge_mcdi_ioctl(struct sfxge_softc *sc, sfxge_ioc_t *ip)
{
        const efx_nic_cfg_t *encp = efx_nic_cfg_get(sc->enp);
        struct sfxge_mcdi *mp = &(sc->mcdi);
        efx_mcdi_req_t emr;
        uint8_t *mcdibuf;
        int rc;

        if (mp->state == SFXGE_MCDI_UNINITIALIZED) {
                rc = ENODEV;
                goto fail1;
        }

        if (!(encp->enc_features & EFX_FEATURE_MCDI)) {
                rc = ENOTSUP;
                goto fail2;
        }

        if (ip->u.mcdi.len > SFXGE_MCDI_MAX_PAYLOAD) {
                rc = EINVAL;
                goto fail3;
        }

        mcdibuf = malloc(SFXGE_MCDI_MAX_PAYLOAD, M_TEMP, M_WAITOK | M_ZERO);
        if ((rc = copyin(ip->u.mcdi.payload, mcdibuf, ip->u.mcdi.len)) != 0) {
                goto fail5;
        }

        emr.emr_cmd = ip->u.mcdi.cmd;
        emr.emr_in_buf = mcdibuf;
        emr.emr_in_length = ip->u.mcdi.len;

        emr.emr_out_buf = mcdibuf;
        emr.emr_out_length = SFXGE_MCDI_MAX_PAYLOAD;

        sfxge_mcdi_execute(sc, &emr);

        ip->u.mcdi.rc = emr.emr_rc;
        ip->u.mcdi.cmd = emr.emr_cmd;
        ip->u.mcdi.len = emr.emr_out_length_used;
        if ((rc = copyout(mcdibuf, ip->u.mcdi.payload, ip->u.mcdi.len)) != 0) {
                goto fail6;
        }

        /*
         * Helpfully trigger a device reset in response to an MCDI_CMD_REBOOT
         * Both ports will see ->emt_exception callbacks on the next MCDI poll
         */
        if (ip->u.mcdi.cmd == MC_CMD_REBOOT) {
                EFSYS_PROBE(mcdi_ioctl_mc_reboot);
                /* sfxge_t->s_state_lock held */
                (void) sfxge_schedule_reset(sc);
        }

        free(mcdibuf, M_TEMP);

        return (0);

fail6:
fail5:
        free(mcdibuf, M_TEMP);
fail3:
fail2:
fail1:
        return (rc);
}

int
sfxge_mcdi_init(struct sfxge_softc *sc)
{
        efx_nic_t *enp;
        struct sfxge_mcdi *mcdi;
        efx_mcdi_transport_t *emtp;
        efsys_mem_t *esmp;
        int max_msg_size;
        int rc;

        enp = sc->enp;
        mcdi = &sc->mcdi;
        emtp = &mcdi->transport;
        esmp = &mcdi->mem;
        max_msg_size = sizeof (uint32_t) + MCDI_CTL_SDU_LEN_MAX_V2;

        KASSERT(mcdi->state == SFXGE_MCDI_UNINITIALIZED,
            ("MCDI already initialized"));

        SFXGE_MCDI_LOCK_INIT(mcdi, device_get_nameunit(sc->dev));

        mcdi->state = SFXGE_MCDI_INITIALIZED;

        if ((rc = sfxge_dma_alloc(sc, max_msg_size, esmp)) != 0)
                goto fail;

        emtp->emt_context = sc;
        emtp->emt_dma_mem = esmp;
        emtp->emt_execute = sfxge_mcdi_execute;
        emtp->emt_ev_cpl = sfxge_mcdi_ev_cpl;
        emtp->emt_exception = sfxge_mcdi_exception;
#if EFSYS_OPT_MCDI_LOGGING
        emtp->emt_logger = sfxge_mcdi_logger;
        SYSCTL_ADD_INT(device_get_sysctl_ctx(sc->dev),
                       SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)),
                       OID_AUTO, "mcdi_logging", CTLFLAG_RW,
                       &sc->mcdi_logging, 0,
                       "MCDI logging");
#endif

        if ((rc = efx_mcdi_init(enp, emtp)) != 0)
                goto fail;

        return (0);

fail:
        SFXGE_MCDI_LOCK_DESTROY(mcdi);
        mcdi->state = SFXGE_MCDI_UNINITIALIZED;
        return (rc);
}

void
sfxge_mcdi_fini(struct sfxge_softc *sc)
{
        struct sfxge_mcdi *mcdi;
        efx_nic_t *enp;
        efx_mcdi_transport_t *emtp;
        efsys_mem_t *esmp;

        enp = sc->enp;
        mcdi = &sc->mcdi;
        emtp = &mcdi->transport;
        esmp = &mcdi->mem;

        SFXGE_MCDI_LOCK(mcdi);
        KASSERT(mcdi->state == SFXGE_MCDI_INITIALIZED,
            ("MCDI not initialized"));

        efx_mcdi_fini(enp);
        bzero(emtp, sizeof(*emtp));

        SFXGE_MCDI_UNLOCK(mcdi);

        sfxge_dma_free(esmp);

        SFXGE_MCDI_LOCK_DESTROY(mcdi);
}