import 15.2.0 Octopus source

[ceph.git] / ceph / src / spdk / dpdk / drivers / net / sfc / sfc_ev.c

/* SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2016-2018 Solarflare Communications Inc.
 * All rights reserved.
 *
 * This software was jointly developed between OKTET Labs (under contract
 * for Solarflare) and Solarflare Communications, Inc.
 */

#include <rte_debug.h>
#include <rte_cycles.h>
#include <rte_alarm.h>
#include <rte_branch_prediction.h>

#include "efx.h"

#include "sfc.h"
#include "sfc_debug.h"
#include "sfc_log.h"
#include "sfc_ev.h"
#include "sfc_rx.h"
#include "sfc_tx.h"
#include "sfc_kvargs.h"


/* Initial delay when waiting for event queue init complete event */
#define SFC_EVQ_INIT_BACKOFF_START_US   (1)
/* Maximum delay between event queue polling attempts */
#define SFC_EVQ_INIT_BACKOFF_MAX_US     (10 * 1000)
/* Event queue init approx timeout */
#define SFC_EVQ_INIT_TIMEOUT_US         (2 * US_PER_S)

/* Management event queue polling period in microseconds */
#define SFC_MGMT_EV_QPOLL_PERIOD_US     (US_PER_S)

static const char *
sfc_evq_type2str(enum sfc_evq_type type)
{
        switch (type) {
        case SFC_EVQ_TYPE_MGMT:
                return "mgmt-evq";
        case SFC_EVQ_TYPE_RX:
                return "rx-evq";
        case SFC_EVQ_TYPE_TX:
                return "tx-evq";
        default:
                SFC_ASSERT(B_FALSE);
                return NULL;
        }
}

static boolean_t
sfc_ev_initialized(void *arg)
{
        struct sfc_evq *evq = arg;

        /* Init done events may be duplicated on SFN7xxx (SFC bug 31631) */
        SFC_ASSERT(evq->init_state == SFC_EVQ_STARTING ||
                   evq->init_state == SFC_EVQ_STARTED);

        evq->init_state = SFC_EVQ_STARTED;

        return B_FALSE;
}

static boolean_t
sfc_ev_nop_rx(void *arg, uint32_t label, uint32_t id,
              uint32_t size, uint16_t flags)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa,
                "EVQ %u unexpected Rx event label=%u id=%#x size=%u flags=%#x",
                evq->evq_index, label, id, size, flags);
        return B_TRUE;
}

static boolean_t
sfc_ev_efx_rx(void *arg, __rte_unused uint32_t label, uint32_t id,
              uint32_t size, uint16_t flags)
{
        struct sfc_evq *evq = arg;
        struct sfc_efx_rxq *rxq;
        unsigned int stop;
        unsigned int pending_id;
        unsigned int delta;
        unsigned int i;
        struct sfc_efx_rx_sw_desc *rxd;

        if (unlikely(evq->exception))
                goto done;

        rxq = sfc_efx_rxq_by_dp_rxq(evq->dp_rxq);

        SFC_ASSERT(rxq != NULL);
        SFC_ASSERT(rxq->evq == evq);
        SFC_ASSERT(rxq->flags & SFC_EFX_RXQ_FLAG_STARTED);

        stop = (id + 1) & rxq->ptr_mask;
        pending_id = rxq->pending & rxq->ptr_mask;
        delta = (stop >= pending_id) ? (stop - pending_id) :
                (rxq->ptr_mask + 1 - pending_id + stop);

        if (delta == 0) {
                /*
                 * Rx event with no new descriptors done and zero length
                 * is used to abort scattered packet when there is no room
                 * for the tail.
                 */
                if (unlikely(size != 0)) {
                        evq->exception = B_TRUE;
                        sfc_err(evq->sa,
                                "EVQ %u RxQ %u invalid RX abort "
                                "(id=%#x size=%u flags=%#x); needs restart",
                                evq->evq_index, rxq->dp.dpq.queue_id,
                                id, size, flags);
                        goto done;
                }

                /* Add discard flag to the first fragment */
                rxq->sw_desc[pending_id].flags |= EFX_DISCARD;
                /* Remove continue flag from the last fragment */
                rxq->sw_desc[id].flags &= ~EFX_PKT_CONT;
        } else if (unlikely(delta > rxq->batch_max)) {
                evq->exception = B_TRUE;

                sfc_err(evq->sa,
                        "EVQ %u RxQ %u completion out of order "
                        "(id=%#x delta=%u flags=%#x); needs restart",
                        evq->evq_index, rxq->dp.dpq.queue_id,
                        id, delta, flags);

                goto done;
        }

        for (i = pending_id; i != stop; i = (i + 1) & rxq->ptr_mask) {
                rxd = &rxq->sw_desc[i];

                rxd->flags = flags;

                SFC_ASSERT(size < (1 << 16));
                rxd->size = (uint16_t)size;
        }

        rxq->pending += delta;

done:
        return B_FALSE;
}

static boolean_t
sfc_ev_dp_rx(void *arg, __rte_unused uint32_t label, uint32_t id,
             __rte_unused uint32_t size, __rte_unused uint16_t flags)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_rxq *dp_rxq;

        dp_rxq = evq->dp_rxq;
        SFC_ASSERT(dp_rxq != NULL);

        SFC_ASSERT(evq->sa->priv.dp_rx->qrx_ev != NULL);
        return evq->sa->priv.dp_rx->qrx_ev(dp_rxq, id);
}

static boolean_t
sfc_ev_nop_rx_ps(void *arg, uint32_t label, uint32_t id,
                 uint32_t pkt_count, uint16_t flags)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa,
                "EVQ %u unexpected packed stream Rx event label=%u id=%#x pkt_count=%u flags=%#x",
                evq->evq_index, label, id, pkt_count, flags);
        return B_TRUE;
}

/* It is not actually used on datapath, but required on RxQ flush */
static boolean_t
sfc_ev_dp_rx_ps(void *arg, __rte_unused uint32_t label, uint32_t id,
                __rte_unused uint32_t pkt_count, __rte_unused uint16_t flags)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_rxq *dp_rxq;

        dp_rxq = evq->dp_rxq;
        SFC_ASSERT(dp_rxq != NULL);

        if (evq->sa->priv.dp_rx->qrx_ps_ev != NULL)
                return evq->sa->priv.dp_rx->qrx_ps_ev(dp_rxq, id);
        else
                return B_FALSE;
}

static boolean_t
sfc_ev_nop_tx(void *arg, uint32_t label, uint32_t id)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected Tx event label=%u id=%#x",
                evq->evq_index, label, id);
        return B_TRUE;
}

static boolean_t
sfc_ev_tx(void *arg, __rte_unused uint32_t label, uint32_t id)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_txq *dp_txq;
        struct sfc_efx_txq *txq;
        unsigned int stop;
        unsigned int delta;

        dp_txq = evq->dp_txq;
        SFC_ASSERT(dp_txq != NULL);

        txq = sfc_efx_txq_by_dp_txq(dp_txq);
        SFC_ASSERT(txq->evq == evq);

        if (unlikely((txq->flags & SFC_EFX_TXQ_FLAG_STARTED) == 0))
                goto done;

        stop = (id + 1) & txq->ptr_mask;
        id = txq->pending & txq->ptr_mask;

        delta = (stop >= id) ? (stop - id) : (txq->ptr_mask + 1 - id + stop);

        txq->pending += delta;

done:
        return B_FALSE;
}

static boolean_t
sfc_ev_dp_tx(void *arg, __rte_unused uint32_t label, uint32_t id)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_txq *dp_txq;

        dp_txq = evq->dp_txq;
        SFC_ASSERT(dp_txq != NULL);

        SFC_ASSERT(evq->sa->priv.dp_tx->qtx_ev != NULL);
        return evq->sa->priv.dp_tx->qtx_ev(dp_txq, id);
}

static boolean_t
sfc_ev_exception(void *arg, uint32_t code, __rte_unused uint32_t data)
{
        struct sfc_evq *evq = arg;

        if (code == EFX_EXCEPTION_UNKNOWN_SENSOREVT)
                return B_FALSE;

        evq->exception = B_TRUE;
        sfc_warn(evq->sa,
                 "hardware exception %s (code=%u, data=%#x) on EVQ %u;"
                 " needs recovery",
                 (code == EFX_EXCEPTION_RX_RECOVERY) ? "RX_RECOVERY" :
                 (code == EFX_EXCEPTION_RX_DSC_ERROR) ? "RX_DSC_ERROR" :
                 (code == EFX_EXCEPTION_TX_DSC_ERROR) ? "TX_DSC_ERROR" :
                 (code == EFX_EXCEPTION_FWALERT_SRAM) ? "FWALERT_SRAM" :
                 (code == EFX_EXCEPTION_UNKNOWN_FWALERT) ? "UNKNOWN_FWALERT" :
                 (code == EFX_EXCEPTION_RX_ERROR) ? "RX_ERROR" :
                 (code == EFX_EXCEPTION_TX_ERROR) ? "TX_ERROR" :
                 (code == EFX_EXCEPTION_EV_ERROR) ? "EV_ERROR" :
                 "UNKNOWN",
                 code, data, evq->evq_index);

        return B_TRUE;
}

static boolean_t
sfc_ev_nop_rxq_flush_done(void *arg, uint32_t rxq_hw_index)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected RxQ %u flush done",
                evq->evq_index, rxq_hw_index);
        return B_TRUE;
}

static boolean_t
sfc_ev_rxq_flush_done(void *arg, __rte_unused uint32_t rxq_hw_index)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_rxq *dp_rxq;
        struct sfc_rxq *rxq;

        dp_rxq = evq->dp_rxq;
        SFC_ASSERT(dp_rxq != NULL);

        rxq = sfc_rxq_by_dp_rxq(dp_rxq);
        SFC_ASSERT(rxq != NULL);
        SFC_ASSERT(rxq->hw_index == rxq_hw_index);
        SFC_ASSERT(rxq->evq == evq);
        RTE_SET_USED(rxq);

        sfc_rx_qflush_done(sfc_rxq_info_by_dp_rxq(dp_rxq));

        return B_FALSE;
}

static boolean_t
sfc_ev_nop_rxq_flush_failed(void *arg, uint32_t rxq_hw_index)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected RxQ %u flush failed",
                evq->evq_index, rxq_hw_index);
        return B_TRUE;
}

static boolean_t
sfc_ev_rxq_flush_failed(void *arg, __rte_unused uint32_t rxq_hw_index)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_rxq *dp_rxq;
        struct sfc_rxq *rxq;

        dp_rxq = evq->dp_rxq;
        SFC_ASSERT(dp_rxq != NULL);

        rxq = sfc_rxq_by_dp_rxq(dp_rxq);
        SFC_ASSERT(rxq != NULL);
        SFC_ASSERT(rxq->hw_index == rxq_hw_index);
        SFC_ASSERT(rxq->evq == evq);
        RTE_SET_USED(rxq);

        sfc_rx_qflush_failed(sfc_rxq_info_by_dp_rxq(dp_rxq));

        return B_FALSE;
}

static boolean_t
sfc_ev_nop_txq_flush_done(void *arg, uint32_t txq_hw_index)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected TxQ %u flush done",
                evq->evq_index, txq_hw_index);
        return B_TRUE;
}

static boolean_t
sfc_ev_txq_flush_done(void *arg, __rte_unused uint32_t txq_hw_index)
{
        struct sfc_evq *evq = arg;
        struct sfc_dp_txq *dp_txq;
        struct sfc_txq *txq;

        dp_txq = evq->dp_txq;
        SFC_ASSERT(dp_txq != NULL);

        txq = sfc_txq_by_dp_txq(dp_txq);
        SFC_ASSERT(txq != NULL);
        SFC_ASSERT(txq->hw_index == txq_hw_index);
        SFC_ASSERT(txq->evq == evq);
        RTE_SET_USED(txq);

        sfc_tx_qflush_done(sfc_txq_info_by_dp_txq(dp_txq));

        return B_FALSE;
}

static boolean_t
sfc_ev_software(void *arg, uint16_t magic)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected software event magic=%#.4x",
                evq->evq_index, magic);
        return B_TRUE;
}

static boolean_t
sfc_ev_sram(void *arg, uint32_t code)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected SRAM event code=%u",
                evq->evq_index, code);
        return B_TRUE;
}

static boolean_t
sfc_ev_wake_up(void *arg, uint32_t index)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected wake up event index=%u",
                evq->evq_index, index);
        return B_TRUE;
}

static boolean_t
sfc_ev_timer(void *arg, uint32_t index)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected timer event index=%u",
                evq->evq_index, index);
        return B_TRUE;
}

static boolean_t
sfc_ev_nop_link_change(void *arg, __rte_unused efx_link_mode_t link_mode)
{
        struct sfc_evq *evq = arg;

        sfc_err(evq->sa, "EVQ %u unexpected link change event",
                evq->evq_index);
        return B_TRUE;
}

static boolean_t
sfc_ev_link_change(void *arg, efx_link_mode_t link_mode)
{
        struct sfc_evq *evq = arg;
        struct sfc_adapter *sa = evq->sa;
        struct rte_eth_link new_link;

        sfc_port_link_mode_to_info(link_mode, &new_link);
        if (rte_eth_linkstatus_set(sa->eth_dev, &new_link))
                evq->sa->port.lsc_seq++;

        return B_FALSE;
}

static const efx_ev_callbacks_t sfc_ev_callbacks = {
        .eec_initialized        = sfc_ev_initialized,
        .eec_rx                 = sfc_ev_nop_rx,
        .eec_rx_ps              = sfc_ev_nop_rx_ps,
        .eec_tx                 = sfc_ev_nop_tx,
        .eec_exception          = sfc_ev_exception,
        .eec_rxq_flush_done     = sfc_ev_nop_rxq_flush_done,
        .eec_rxq_flush_failed   = sfc_ev_nop_rxq_flush_failed,
        .eec_txq_flush_done     = sfc_ev_nop_txq_flush_done,
        .eec_software           = sfc_ev_software,
        .eec_sram               = sfc_ev_sram,
        .eec_wake_up            = sfc_ev_wake_up,
        .eec_timer              = sfc_ev_timer,
        .eec_link_change        = sfc_ev_link_change,
};

static const efx_ev_callbacks_t sfc_ev_callbacks_efx_rx = {
        .eec_initialized        = sfc_ev_initialized,
        .eec_rx                 = sfc_ev_efx_rx,
        .eec_rx_ps              = sfc_ev_nop_rx_ps,
        .eec_tx                 = sfc_ev_nop_tx,
        .eec_exception          = sfc_ev_exception,
        .eec_rxq_flush_done     = sfc_ev_rxq_flush_done,
        .eec_rxq_flush_failed   = sfc_ev_rxq_flush_failed,
        .eec_txq_flush_done     = sfc_ev_nop_txq_flush_done,
        .eec_software           = sfc_ev_software,
        .eec_sram               = sfc_ev_sram,
        .eec_wake_up            = sfc_ev_wake_up,
        .eec_timer              = sfc_ev_timer,
        .eec_link_change        = sfc_ev_nop_link_change,
};

static const efx_ev_callbacks_t sfc_ev_callbacks_dp_rx = {
        .eec_initialized        = sfc_ev_initialized,
        .eec_rx                 = sfc_ev_dp_rx,
        .eec_rx_ps              = sfc_ev_dp_rx_ps,
        .eec_tx                 = sfc_ev_nop_tx,
        .eec_exception          = sfc_ev_exception,
        .eec_rxq_flush_done     = sfc_ev_rxq_flush_done,
        .eec_rxq_flush_failed   = sfc_ev_rxq_flush_failed,
        .eec_txq_flush_done     = sfc_ev_nop_txq_flush_done,
        .eec_software           = sfc_ev_software,
        .eec_sram               = sfc_ev_sram,
        .eec_wake_up            = sfc_ev_wake_up,
        .eec_timer              = sfc_ev_timer,
        .eec_link_change        = sfc_ev_nop_link_change,
};

static const efx_ev_callbacks_t sfc_ev_callbacks_efx_tx = {
        .eec_initialized        = sfc_ev_initialized,
        .eec_rx                 = sfc_ev_nop_rx,
        .eec_rx_ps              = sfc_ev_nop_rx_ps,
        .eec_tx                 = sfc_ev_tx,
        .eec_exception          = sfc_ev_exception,
        .eec_rxq_flush_done     = sfc_ev_nop_rxq_flush_done,
        .eec_rxq_flush_failed   = sfc_ev_nop_rxq_flush_failed,
        .eec_txq_flush_done     = sfc_ev_txq_flush_done,
        .eec_software           = sfc_ev_software,
        .eec_sram               = sfc_ev_sram,
        .eec_wake_up            = sfc_ev_wake_up,
        .eec_timer              = sfc_ev_timer,
        .eec_link_change        = sfc_ev_nop_link_change,
};

static const efx_ev_callbacks_t sfc_ev_callbacks_dp_tx = {
        .eec_initialized        = sfc_ev_initialized,
        .eec_rx                 = sfc_ev_nop_rx,
        .eec_rx_ps              = sfc_ev_nop_rx_ps,
        .eec_tx                 = sfc_ev_dp_tx,
        .eec_exception          = sfc_ev_exception,
        .eec_rxq_flush_done     = sfc_ev_nop_rxq_flush_done,
        .eec_rxq_flush_failed   = sfc_ev_nop_rxq_flush_failed,
        .eec_txq_flush_done     = sfc_ev_txq_flush_done,
        .eec_software           = sfc_ev_software,
        .eec_sram               = sfc_ev_sram,
        .eec_wake_up            = sfc_ev_wake_up,
        .eec_timer              = sfc_ev_timer,
        .eec_link_change        = sfc_ev_nop_link_change,
};


void
sfc_ev_qpoll(struct sfc_evq *evq)
{
        SFC_ASSERT(evq->init_state == SFC_EVQ_STARTED ||
                   evq->init_state == SFC_EVQ_STARTING);

        /* Synchronize the DMA memory for reading not required */

        efx_ev_qpoll(evq->common, &evq->read_ptr, evq->callbacks, evq);

        if (unlikely(evq->exception) && sfc_adapter_trylock(evq->sa)) {
                struct sfc_adapter *sa = evq->sa;
                int rc;

                if (evq->dp_rxq != NULL) {
                        unsigned int rxq_sw_index;

                        rxq_sw_index = evq->dp_rxq->dpq.queue_id;

                        sfc_warn(sa,
                                 "restart RxQ %u because of exception on its EvQ %u",
                                 rxq_sw_index, evq->evq_index);

                        sfc_rx_qstop(sa, rxq_sw_index);
                        rc = sfc_rx_qstart(sa, rxq_sw_index);
                        if (rc != 0)
                                sfc_err(sa, "cannot restart RxQ %u",
                                        rxq_sw_index);
                }

                if (evq->dp_txq != NULL) {
                        unsigned int txq_sw_index;

                        txq_sw_index = evq->dp_txq->dpq.queue_id;

                        sfc_warn(sa,
                                 "restart TxQ %u because of exception on its EvQ %u",
                                 txq_sw_index, evq->evq_index);

                        sfc_tx_qstop(sa, txq_sw_index);
                        rc = sfc_tx_qstart(sa, txq_sw_index);
                        if (rc != 0)
                                sfc_err(sa, "cannot restart TxQ %u",
                                        txq_sw_index);
                }

                if (evq->exception)
                        sfc_panic(sa, "unrecoverable exception on EvQ %u",
                                  evq->evq_index);

                sfc_adapter_unlock(sa);
        }

        /* Poll-mode driver does not re-prime the event queue for interrupts */
}

void
sfc_ev_mgmt_qpoll(struct sfc_adapter *sa)
{
        if (rte_spinlock_trylock(&sa->mgmt_evq_lock)) {
                if (sa->mgmt_evq_running)
                        sfc_ev_qpoll(sa->mgmt_evq);

                rte_spinlock_unlock(&sa->mgmt_evq_lock);
        }
}

int
sfc_ev_qprime(struct sfc_evq *evq)
{
        SFC_ASSERT(evq->init_state == SFC_EVQ_STARTED);
        return efx_ev_qprime(evq->common, evq->read_ptr);
}

/* Event queue HW index allocation scheme is described in sfc_ev.h. */
int
sfc_ev_qstart(struct sfc_evq *evq, unsigned int hw_index)
{
        struct sfc_adapter *sa = evq->sa;
        efsys_mem_t *esmp;
        uint32_t evq_flags = sa->evq_flags;
        unsigned int total_delay_us;
        unsigned int delay_us;
        int rc;

        sfc_log_init(sa, "hw_index=%u", hw_index);

        esmp = &evq->mem;

        evq->evq_index = hw_index;

        /* Clear all events */
        (void)memset((void *)esmp->esm_base, 0xff,
                     efx_evq_size(sa->nic, evq->entries));

        if (sa->intr.lsc_intr && hw_index == sa->mgmt_evq_index)
                evq_flags |= EFX_EVQ_FLAGS_NOTIFY_INTERRUPT;
        else
                evq_flags |= EFX_EVQ_FLAGS_NOTIFY_DISABLED;

        /* Create the common code event queue */
        rc = efx_ev_qcreate(sa->nic, hw_index, esmp, evq->entries,
                            0 /* unused on EF10 */, 0, evq_flags,
                            &evq->common);
        if (rc != 0)
                goto fail_ev_qcreate;

        SFC_ASSERT(evq->dp_rxq == NULL || evq->dp_txq == NULL);
        if (evq->dp_rxq != 0) {
                if (strcmp(sa->priv.dp_rx->dp.name,
                           SFC_KVARG_DATAPATH_EFX) == 0)
                        evq->callbacks = &sfc_ev_callbacks_efx_rx;
                else
                        evq->callbacks = &sfc_ev_callbacks_dp_rx;
        } else if (evq->dp_txq != 0) {
                if (strcmp(sa->priv.dp_tx->dp.name,
                           SFC_KVARG_DATAPATH_EFX) == 0)
                        evq->callbacks = &sfc_ev_callbacks_efx_tx;
                else
                        evq->callbacks = &sfc_ev_callbacks_dp_tx;
        } else {
                evq->callbacks = &sfc_ev_callbacks;
        }

        evq->init_state = SFC_EVQ_STARTING;

        /* Wait for the initialization event */
        total_delay_us = 0;
        delay_us = SFC_EVQ_INIT_BACKOFF_START_US;
        do {
                (void)sfc_ev_qpoll(evq);

                /* Check to see if the initialization complete indication
                 * posted by the hardware.
                 */
                if (evq->init_state == SFC_EVQ_STARTED)
                        goto done;

                /* Give event queue some time to init */
                rte_delay_us(delay_us);

                total_delay_us += delay_us;

                /* Exponential backoff */
                delay_us *= 2;
                if (delay_us > SFC_EVQ_INIT_BACKOFF_MAX_US)
                        delay_us = SFC_EVQ_INIT_BACKOFF_MAX_US;

        } while (total_delay_us < SFC_EVQ_INIT_TIMEOUT_US);

        rc = ETIMEDOUT;
        goto fail_timedout;

done:
        return 0;

fail_timedout:
        evq->init_state = SFC_EVQ_INITIALIZED;
        efx_ev_qdestroy(evq->common);

fail_ev_qcreate:
        sfc_log_init(sa, "failed %d", rc);
        return rc;
}

void
sfc_ev_qstop(struct sfc_evq *evq)
{
        if (evq == NULL)
                return;

        sfc_log_init(evq->sa, "hw_index=%u", evq->evq_index);

        if (evq->init_state != SFC_EVQ_STARTED)
                return;

        evq->init_state = SFC_EVQ_INITIALIZED;
        evq->callbacks = NULL;
        evq->read_ptr = 0;
        evq->exception = B_FALSE;

        efx_ev_qdestroy(evq->common);

        evq->evq_index = 0;
}

static void
sfc_ev_mgmt_periodic_qpoll(void *arg)
{
        struct sfc_adapter *sa = arg;
        int rc;

        sfc_ev_mgmt_qpoll(sa);

        rc = rte_eal_alarm_set(SFC_MGMT_EV_QPOLL_PERIOD_US,
                               sfc_ev_mgmt_periodic_qpoll, sa);
        if (rc == -ENOTSUP) {
                sfc_warn(sa, "alarms are not supported");
                sfc_warn(sa, "management EVQ must be polled indirectly using no-wait link status update");
        } else if (rc != 0) {
                sfc_err(sa,
                        "cannot rearm management EVQ polling alarm (rc=%d)",
                        rc);
        }
}

static void
sfc_ev_mgmt_periodic_qpoll_start(struct sfc_adapter *sa)
{
        sfc_ev_mgmt_periodic_qpoll(sa);
}

static void
sfc_ev_mgmt_periodic_qpoll_stop(struct sfc_adapter *sa)
{
        rte_eal_alarm_cancel(sfc_ev_mgmt_periodic_qpoll, sa);
}

int
sfc_ev_start(struct sfc_adapter *sa)
{
        int rc;

        sfc_log_init(sa, "entry");

        rc = efx_ev_init(sa->nic);
        if (rc != 0)
                goto fail_ev_init;

        /* Start management EVQ used for global events */

        /*
         * Management event queue start polls the queue, but it cannot
         * interfere with other polling contexts since mgmt_evq_running
         * is false yet.
         */
        rc = sfc_ev_qstart(sa->mgmt_evq, sa->mgmt_evq_index);
        if (rc != 0)
                goto fail_mgmt_evq_start;

        rte_spinlock_lock(&sa->mgmt_evq_lock);
        sa->mgmt_evq_running = true;
        rte_spinlock_unlock(&sa->mgmt_evq_lock);

        if (sa->intr.lsc_intr) {
                rc = sfc_ev_qprime(sa->mgmt_evq);
                if (rc != 0)
                        goto fail_mgmt_evq_prime;
        }

        /*
         * Start management EVQ polling. If interrupts are disabled
         * (not used), it is required to process link status change
         * and other device level events to avoid unrecoverable
         * error because the event queue overflow.
         */
        sfc_ev_mgmt_periodic_qpoll_start(sa);

        /*
         * Rx/Tx event queues are started/stopped when corresponding
         * Rx/Tx queue is started/stopped.
         */

        return 0;

fail_mgmt_evq_prime:
        sfc_ev_qstop(sa->mgmt_evq);

fail_mgmt_evq_start:
        efx_ev_fini(sa->nic);

fail_ev_init:
        sfc_log_init(sa, "failed %d", rc);
        return rc;
}

void
sfc_ev_stop(struct sfc_adapter *sa)
{
        sfc_log_init(sa, "entry");

        sfc_ev_mgmt_periodic_qpoll_stop(sa);

        rte_spinlock_lock(&sa->mgmt_evq_lock);
        sa->mgmt_evq_running = false;
        rte_spinlock_unlock(&sa->mgmt_evq_lock);

        sfc_ev_qstop(sa->mgmt_evq);

        efx_ev_fini(sa->nic);
}

int
sfc_ev_qinit(struct sfc_adapter *sa,
             enum sfc_evq_type type, unsigned int type_index,
             unsigned int entries, int socket_id, struct sfc_evq **evqp)
{
        struct sfc_evq *evq;
        int rc;

        sfc_log_init(sa, "type=%s type_index=%u",
                     sfc_evq_type2str(type), type_index);

        SFC_ASSERT(rte_is_power_of_2(entries));

        rc = ENOMEM;
        evq = rte_zmalloc_socket("sfc-evq", sizeof(*evq), RTE_CACHE_LINE_SIZE,
                                 socket_id);
        if (evq == NULL)
                goto fail_evq_alloc;

        evq->sa = sa;
        evq->type = type;
        evq->entries = entries;

        /* Allocate DMA space */
        rc = sfc_dma_alloc(sa, sfc_evq_type2str(type), type_index,
                           efx_evq_size(sa->nic, evq->entries), socket_id,
                           &evq->mem);
        if (rc != 0)
                goto fail_dma_alloc;

        evq->init_state = SFC_EVQ_INITIALIZED;

        sa->evq_count++;

        *evqp = evq;

        return 0;

fail_dma_alloc:
        rte_free(evq);

fail_evq_alloc:

        sfc_log_init(sa, "failed %d", rc);
        return rc;
}

void
sfc_ev_qfini(struct sfc_evq *evq)
{
        struct sfc_adapter *sa = evq->sa;

        SFC_ASSERT(evq->init_state == SFC_EVQ_INITIALIZED);

        sfc_dma_free(sa, &evq->mem);

        rte_free(evq);

        SFC_ASSERT(sa->evq_count > 0);
        sa->evq_count--;
}

static int
sfc_kvarg_perf_profile_handler(__rte_unused const char *key,
                               const char *value_str, void *opaque)
{
        uint32_t *value = opaque;

        if (strcasecmp(value_str, SFC_KVARG_PERF_PROFILE_THROUGHPUT) == 0)
                *value = EFX_EVQ_FLAGS_TYPE_THROUGHPUT;
        else if (strcasecmp(value_str, SFC_KVARG_PERF_PROFILE_LOW_LATENCY) == 0)
                *value = EFX_EVQ_FLAGS_TYPE_LOW_LATENCY;
        else if (strcasecmp(value_str, SFC_KVARG_PERF_PROFILE_AUTO) == 0)
                *value = EFX_EVQ_FLAGS_TYPE_AUTO;
        else
                return -EINVAL;

        return 0;
}

int
sfc_ev_attach(struct sfc_adapter *sa)
{
        int rc;

        sfc_log_init(sa, "entry");

        sa->evq_flags = EFX_EVQ_FLAGS_TYPE_THROUGHPUT;
        rc = sfc_kvargs_process(sa, SFC_KVARG_PERF_PROFILE,
                                sfc_kvarg_perf_profile_handler,
                                &sa->evq_flags);
        if (rc != 0) {
                sfc_err(sa, "invalid %s parameter value",
                        SFC_KVARG_PERF_PROFILE);
                goto fail_kvarg_perf_profile;
        }

        sa->mgmt_evq_index = 0;
        rte_spinlock_init(&sa->mgmt_evq_lock);

        rc = sfc_ev_qinit(sa, SFC_EVQ_TYPE_MGMT, 0, sa->evq_min_entries,
                          sa->socket_id, &sa->mgmt_evq);
        if (rc != 0)
                goto fail_mgmt_evq_init;

        /*
         * Rx/Tx event queues are created/destroyed when corresponding
         * Rx/Tx queue is created/destroyed.
         */

        return 0;

fail_mgmt_evq_init:

fail_kvarg_perf_profile:
        sfc_log_init(sa, "failed %d", rc);
        return rc;
}

void
sfc_ev_detach(struct sfc_adapter *sa)
{
        sfc_log_init(sa, "entry");

        sfc_ev_qfini(sa->mgmt_evq);

        if (sa->evq_count != 0)
                sfc_err(sa, "%u EvQs are not destroyed before detach",
                        sa->evq_count);
}