mcdi.c

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/****************************************************************************
 * Driver for Solarflare Solarstorm network controllers and boards
 * Copyright 2008-2011 Solarflare Communications Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */

#include <linux/delay.h>
#include "net_driver.h"
#include "nic.h"
#include "io.h"
#include "regs.h"
#include "mcdi_pcol.h"
#include "phy.h"

/**************************************************************************
 *
 * Management-Controller-to-Driver Interface
 *
 **************************************************************************
 */

#define MCDI_RPC_TIMEOUT       10 /*seconds */

#define MCDI_PDU(efx)                           \
    (efx_port_num(efx) ? MC_SMEM_P1_PDU_OFST : MC_SMEM_P0_PDU_OFST)
#define MCDI_DOORBELL(efx)                      \
    (efx_port_num(efx) ? MC_SMEM_P1_DOORBELL_OFST : MC_SMEM_P0_DOORBELL_OFST)
#define MCDI_STATUS(efx)                        \
    (efx_port_num(efx) ? MC_SMEM_P1_STATUS_OFST : MC_SMEM_P0_STATUS_OFST)

/* A reboot/assertion causes the MCDI status word to be set after the
 * command word is set or a REBOOT event is sent. If we notice a reboot
 * via these mechanisms then wait 10ms for the status word to be set. */
#define MCDI_STATUS_DELAY_US        100
#define MCDI_STATUS_DELAY_COUNT     100
#define MCDI_STATUS_SLEEP_MS                        \
    (MCDI_STATUS_DELAY_US * MCDI_STATUS_DELAY_COUNT / 1000)

#define SEQ_MASK                            \
    EFX_MASK32(EFX_WIDTH(MCDI_HEADER_SEQ))

static inline struct efx_mcdi_iface *efx_mcdi(struct efx_nic *efx)
{
    struct siena_nic_data *nic_data;
    EFX_BUG_ON_PARANOID(efx_nic_rev(efx) < EFX_REV_SIENA_A0);
    nic_data = efx->nic_data;
    return &nic_data->mcdi;
}

void efx_mcdi_init(struct efx_nic *efx)
{
    struct efx_mcdi_iface *mcdi;

    if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
        return;

    mcdi = efx_mcdi(efx);
    init_waitqueue_head(&mcdi->wq);
    spin_lock_init(&mcdi->iface_lock);
    atomic_set(&mcdi->state, MCDI_STATE_QUIESCENT);
    mcdi->mode = MCDI_MODE_POLL;

    (void) efx_mcdi_poll_reboot(efx);
}

static void efx_mcdi_copyin(struct efx_nic *efx, unsigned cmd,
                const u8 *inbuf, size_t inlen)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
    unsigned pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
    unsigned doorbell = FR_CZ_MC_TREG_SMEM + MCDI_DOORBELL(efx);
    unsigned int i;
    efx_dword_t hdr;
    u32 xflags, seqno;

    BUG_ON(atomic_read(&mcdi->state) == MCDI_STATE_QUIESCENT);
    BUG_ON(inlen & 3 || inlen >= MC_SMEM_PDU_LEN);

    seqno = mcdi->seqno & SEQ_MASK;
    xflags = 0;
    if (mcdi->mode == MCDI_MODE_EVENTS)
        xflags |= MCDI_HEADER_XFLAGS_EVREQ;

    EFX_POPULATE_DWORD_6(hdr,
                 MCDI_HEADER_RESPONSE, 0,
                 MCDI_HEADER_RESYNC, 1,
                 MCDI_HEADER_CODE, cmd,
                 MCDI_HEADER_DATALEN, inlen,
                 MCDI_HEADER_SEQ, seqno,
                 MCDI_HEADER_XFLAGS, xflags);

    efx_writed(efx, &hdr, pdu);

    for (i = 0; i < inlen; i += 4)
        _efx_writed(efx, *((__le32 *)(inbuf + i)), pdu + 4 + i);

    /* Ensure the payload is written out before the header */
    wmb();

    /* ring the doorbell with a distinctive value */
    _efx_writed(efx, (__force __le32) 0x45789abc, doorbell);
}

static void efx_mcdi_copyout(struct efx_nic *efx, u8 *outbuf, size_t outlen)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
    unsigned int pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
    int i;

    BUG_ON(atomic_read(&mcdi->state) == MCDI_STATE_QUIESCENT);
    BUG_ON(outlen & 3 || outlen >= MC_SMEM_PDU_LEN);

    for (i = 0; i < outlen; i += 4)
        *((__le32 *)(outbuf + i)) = _efx_readd(efx, pdu + 4 + i);
}

static int efx_mcdi_poll(struct efx_nic *efx)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
    unsigned int time, finish;
    unsigned int respseq, respcmd, error;
    unsigned int pdu = FR_CZ_MC_TREG_SMEM + MCDI_PDU(efx);
    unsigned int rc, spins;
    efx_dword_t reg;

    /* Check for a reboot atomically with respect to efx_mcdi_copyout() */
    rc = -efx_mcdi_poll_reboot(efx);
    if (rc)
        goto out;

    /* Poll for completion. Poll quickly (once a us) for the 1st jiffy,
     * because generally mcdi responses are fast. After that, back off
     * and poll once a jiffy (approximately)
     */
    spins = TICK_USEC;
    finish = get_seconds() + MCDI_RPC_TIMEOUT;

    while (1) {
        if (spins != 0) {
            --spins;
            udelay(1);
        } else {
            schedule_timeout_uninterruptible(1);
        }

        time = get_seconds();

        rmb();
        efx_readd(efx, &reg, pdu);

        /* All 1's indicates that shared memory is in reset (and is
         * not a valid header). Wait for it to come out reset before
         * completing the command */
        if (EFX_DWORD_FIELD(reg, EFX_DWORD_0) != 0xffffffff &&
            EFX_DWORD_FIELD(reg, MCDI_HEADER_RESPONSE))
            break;

        if (time >= finish)
            return -ETIMEDOUT;
    }

    mcdi->resplen = EFX_DWORD_FIELD(reg, MCDI_HEADER_DATALEN);
    respseq = EFX_DWORD_FIELD(reg, MCDI_HEADER_SEQ);
    respcmd = EFX_DWORD_FIELD(reg, MCDI_HEADER_CODE);
    error = EFX_DWORD_FIELD(reg, MCDI_HEADER_ERROR);

    if (error && mcdi->resplen == 0) {
        netif_err(efx, hw, efx->net_dev, "MC rebooted\n");
        rc = EIO;
    } else if ((respseq ^ mcdi->seqno) & SEQ_MASK) {
        netif_err(efx, hw, efx->net_dev,
              "MC response mismatch tx seq 0x%x rx seq 0x%x\n",
              respseq, mcdi->seqno);
        rc = EIO;
    } else if (error) {
        efx_readd(efx, &reg, pdu + 4);
        switch (EFX_DWORD_FIELD(reg, EFX_DWORD_0)) {
#define TRANSLATE_ERROR(name)                   \
        case MC_CMD_ERR_ ## name:           \
            rc = name;              \
            break
            TRANSLATE_ERROR(ENOENT);
            TRANSLATE_ERROR(EINTR);
            TRANSLATE_ERROR(EACCES);
            TRANSLATE_ERROR(EBUSY);
            TRANSLATE_ERROR(EINVAL);
            TRANSLATE_ERROR(EDEADLK);
            TRANSLATE_ERROR(ENOSYS);
            TRANSLATE_ERROR(ETIME);
#undef TRANSLATE_ERROR
        default:
            rc = EIO;
            break;
        }
    } else
        rc = 0;

out:
    mcdi->resprc = rc;
    if (rc)
        mcdi->resplen = 0;

    /* Return rc=0 like wait_event_timeout() */
    return 0;
}

/* Test and clear MC-rebooted flag for this port/function */
int efx_mcdi_poll_reboot(struct efx_nic *efx)
{
    unsigned int addr = FR_CZ_MC_TREG_SMEM + MCDI_STATUS(efx);
    efx_dword_t reg;
    uint32_t value;

    if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
        return false;

    efx_readd(efx, &reg, addr);
    value = EFX_DWORD_FIELD(reg, EFX_DWORD_0);

    if (value == 0)
        return 0;

    EFX_ZERO_DWORD(reg);
    efx_writed(efx, &reg, addr);

    if (value == MC_STATUS_DWORD_ASSERT)
        return -EINTR;
    else
        return -EIO;
}

static void efx_mcdi_acquire(struct efx_mcdi_iface *mcdi)
{
    /* Wait until the interface becomes QUIESCENT and we win the race
     * to mark it RUNNING. */
    wait_event(mcdi->wq,
           atomic_cmpxchg(&mcdi->state,
                  MCDI_STATE_QUIESCENT,
                  MCDI_STATE_RUNNING)
           == MCDI_STATE_QUIESCENT);
}

static int efx_mcdi_await_completion(struct efx_nic *efx)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);

    if (wait_event_timeout(
            mcdi->wq,
            atomic_read(&mcdi->state) == MCDI_STATE_COMPLETED,
            msecs_to_jiffies(MCDI_RPC_TIMEOUT * 1000)) == 0)
        return -ETIMEDOUT;

    /* Check if efx_mcdi_set_mode() switched us back to polled completions.
     * In which case, poll for completions directly. If efx_mcdi_ev_cpl()
     * completed the request first, then we'll just end up completing the
     * request again, which is safe.
     *
     * We need an smp_rmb() to synchronise with efx_mcdi_mode_poll(), which
     * wait_event_timeout() implicitly provides.
     */
    if (mcdi->mode == MCDI_MODE_POLL)
        return efx_mcdi_poll(efx);

    return 0;
}

static bool efx_mcdi_complete(struct efx_mcdi_iface *mcdi)
{
    /* If the interface is RUNNING, then move to COMPLETED and wake any
     * waiters. If the interface isn't in RUNNING then we've received a
     * duplicate completion after we've already transitioned back to
     * QUIESCENT. [A subsequent invocation would increment seqno, so would
     * have failed the seqno check].
     */
    if (atomic_cmpxchg(&mcdi->state,
               MCDI_STATE_RUNNING,
               MCDI_STATE_COMPLETED) == MCDI_STATE_RUNNING) {
        wake_up(&mcdi->wq);
        return true;
    }

    return false;
}

static void efx_mcdi_release(struct efx_mcdi_iface *mcdi)
{
    atomic_set(&mcdi->state, MCDI_STATE_QUIESCENT);
    wake_up(&mcdi->wq);
}

static void efx_mcdi_ev_cpl(struct efx_nic *efx, unsigned int seqno,
                unsigned int datalen, unsigned int errno)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
    bool wake = false;

    spin_lock(&mcdi->iface_lock);

    if ((seqno ^ mcdi->seqno) & SEQ_MASK) {
        if (mcdi->credits)
            /* The request has been cancelled */
            --mcdi->credits;
        else
            netif_err(efx, hw, efx->net_dev,
                  "MC response mismatch tx seq 0x%x rx "
                  "seq 0x%x\n", seqno, mcdi->seqno);
    } else {
        mcdi->resprc = errno;
        mcdi->resplen = datalen;

        wake = true;
    }

    spin_unlock(&mcdi->iface_lock);

    if (wake)
        efx_mcdi_complete(mcdi);
}

int efx_mcdi_rpc(struct efx_nic *efx, unsigned cmd,
         const u8 *inbuf, size_t inlen, u8 *outbuf, size_t outlen,
         size_t *outlen_actual)
{
    efx_mcdi_rpc_start(efx, cmd, inbuf, inlen);
    return efx_mcdi_rpc_finish(efx, cmd, inlen,
                   outbuf, outlen, outlen_actual);
}

void efx_mcdi_rpc_start(struct efx_nic *efx, unsigned cmd, const u8 *inbuf,
            size_t inlen)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);

    BUG_ON(efx_nic_rev(efx) < EFX_REV_SIENA_A0);

    efx_mcdi_acquire(mcdi);

    /* Serialise with efx_mcdi_ev_cpl() and efx_mcdi_ev_death() */
    spin_lock_bh(&mcdi->iface_lock);
    ++mcdi->seqno;
    spin_unlock_bh(&mcdi->iface_lock);

    efx_mcdi_copyin(efx, cmd, inbuf, inlen);
}

int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
            u8 *outbuf, size_t outlen, size_t *outlen_actual)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
    int rc;

    BUG_ON(efx_nic_rev(efx) < EFX_REV_SIENA_A0);

    if (mcdi->mode == MCDI_MODE_POLL)
        rc = efx_mcdi_poll(efx);
    else
        rc = efx_mcdi_await_completion(efx);

    if (rc != 0) {
        /* Close the race with efx_mcdi_ev_cpl() executing just too late
         * and completing a request we've just cancelled, by ensuring
         * that the seqno check therein fails.
         */
        spin_lock_bh(&mcdi->iface_lock);
        ++mcdi->seqno;
        ++mcdi->credits;
        spin_unlock_bh(&mcdi->iface_lock);

        netif_err(efx, hw, efx->net_dev,
              "MC command 0x%x inlen %d mode %d timed out\n",
              cmd, (int)inlen, mcdi->mode);
    } else {
        size_t resplen;

        /* At the very least we need a memory barrier here to ensure
         * we pick up changes from efx_mcdi_ev_cpl(). Protect against
         * a spurious efx_mcdi_ev_cpl() running concurrently by
         * acquiring the iface_lock. */
        spin_lock_bh(&mcdi->iface_lock);
        rc = -mcdi->resprc;
        resplen = mcdi->resplen;
        spin_unlock_bh(&mcdi->iface_lock);

        if (rc == 0) {
            efx_mcdi_copyout(efx, outbuf,
                     min(outlen, mcdi->resplen + 3) & ~0x3);
            if (outlen_actual != NULL)
                *outlen_actual = resplen;
        } else if (cmd == MC_CMD_REBOOT && rc == -EIO)
            ; /* Don't reset if MC_CMD_REBOOT returns EIO */
        else if (rc == -EIO || rc == -EINTR) {
            netif_err(efx, hw, efx->net_dev, "MC fatal error %d\n",
                  -rc);
            efx_schedule_reset(efx, RESET_TYPE_MC_FAILURE);
        } else
            netif_dbg(efx, hw, efx->net_dev,
                  "MC command 0x%x inlen %d failed rc=%d\n",
                  cmd, (int)inlen, -rc);

        if (rc == -EIO || rc == -EINTR) {
            msleep(MCDI_STATUS_SLEEP_MS);
            efx_mcdi_poll_reboot(efx);
        }
    }

    efx_mcdi_release(mcdi);
    return rc;
}

void efx_mcdi_mode_poll(struct efx_nic *efx)
{
    struct efx_mcdi_iface *mcdi;

    if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
        return;

    mcdi = efx_mcdi(efx);
    if (mcdi->mode == MCDI_MODE_POLL)
        return;

    /* We can switch from event completion to polled completion, because
     * mcdi requests are always completed in shared memory. We do this by
     * switching the mode to POLL'd then completing the request.
     * efx_mcdi_await_completion() will then call efx_mcdi_poll().
     *
     * We need an smp_wmb() to synchronise with efx_mcdi_await_completion(),
     * which efx_mcdi_complete() provides for us.
     */
    mcdi->mode = MCDI_MODE_POLL;

    efx_mcdi_complete(mcdi);
}

void efx_mcdi_mode_event(struct efx_nic *efx)
{
    struct efx_mcdi_iface *mcdi;

    if (efx_nic_rev(efx) < EFX_REV_SIENA_A0)
        return;

    mcdi = efx_mcdi(efx);

    if (mcdi->mode == MCDI_MODE_EVENTS)
        return;

    /* We can't switch from polled to event completion in the middle of a
     * request, because the completion method is specified in the request.
     * So acquire the interface to serialise the requestors. We don't need
     * to acquire the iface_lock to change the mode here, but we do need a
     * write memory barrier ensure that efx_mcdi_rpc() sees it, which
     * efx_mcdi_acquire() provides.
     */
    efx_mcdi_acquire(mcdi);
    mcdi->mode = MCDI_MODE_EVENTS;
    efx_mcdi_release(mcdi);
}

static void efx_mcdi_ev_death(struct efx_nic *efx, int rc)
{
    struct efx_mcdi_iface *mcdi = efx_mcdi(efx);

    /* If there is an outstanding MCDI request, it has been terminated
     * either by a BADASSERT or REBOOT event. If the mcdi interface is
     * in polled mode, then do nothing because the MC reboot handler will
     * set the header correctly. However, if the mcdi interface is waiting
     * for a CMDDONE event it won't receive it [and since all MCDI events
     * are sent to the same queue, we can't be racing with
     * efx_mcdi_ev_cpl()]
     *
     * There's a race here with efx_mcdi_rpc(), because we might receive
     * a REBOOT event *before* the request has been copied out. In polled
     * mode (during startup) this is irrelevant, because efx_mcdi_complete()
     * is ignored. In event mode, this condition is just an edge-case of
     * receiving a REBOOT event after posting the MCDI request. Did the mc
     * reboot before or after the copyout? The best we can do always is
     * just return failure.
     */
    spin_lock(&mcdi->iface_lock);
    if (efx_mcdi_complete(mcdi)) {
        if (mcdi->mode == MCDI_MODE_EVENTS) {
            mcdi->resprc = rc;
            mcdi->resplen = 0;
            ++mcdi->credits;
        }
    } else {
        int count;

        /* Nobody was waiting for an MCDI request, so trigger a reset */
        efx_schedule_reset(efx, RESET_TYPE_MC_FAILURE);

        /* Consume the status word since efx_mcdi_rpc_finish() won't */
        for (count = 0; count < MCDI_STATUS_DELAY_COUNT; ++count) {
            if (efx_mcdi_poll_reboot(efx))
                break;
            udelay(MCDI_STATUS_DELAY_US);
        }
    }

    spin_unlock(&mcdi->iface_lock);
}

static unsigned int efx_mcdi_event_link_speed[] = {
    [MCDI_EVENT_LINKCHANGE_SPEED_100M] = 100,
    [MCDI_EVENT_LINKCHANGE_SPEED_1G] = 1000,
    [MCDI_EVENT_LINKCHANGE_SPEED_10G] = 10000,
};


static void efx_mcdi_process_link_change(struct efx_nic *efx, efx_qword_t *ev)
{
    u32 flags, fcntl, speed, lpa;

    speed = EFX_QWORD_FIELD(*ev, MCDI_EVENT_LINKCHANGE_SPEED);
    EFX_BUG_ON_PARANOID(speed >= ARRAY_SIZE(efx_mcdi_event_link_speed));
    speed = efx_mcdi_event_link_speed[speed];

    flags = EFX_QWORD_FIELD(*ev, MCDI_EVENT_LINKCHANGE_LINK_FLAGS);
    fcntl = EFX_QWORD_FIELD(*ev, MCDI_EVENT_LINKCHANGE_FCNTL);
    lpa = EFX_QWORD_FIELD(*ev, MCDI_EVENT_LINKCHANGE_LP_CAP);

    /* efx->link_state is only modified by efx_mcdi_phy_get_link(),
     * which is only run after flushing the event queues. Therefore, it
     * is safe to modify the link state outside of the mac_lock here.
     */
    efx_mcdi_phy_decode_link(efx, &efx->link_state, speed, flags, fcntl);

    efx_mcdi_phy_check_fcntl(efx, lpa);

    efx_link_status_changed(efx);
}

/* Called from  falcon_process_eventq for MCDI events */
void efx_mcdi_process_event(struct efx_channel *channel,
                efx_qword_t *event)
{
    struct efx_nic *efx = channel->efx;
    int code = EFX_QWORD_FIELD(*event, MCDI_EVENT_CODE);
    u32 data = EFX_QWORD_FIELD(*event, MCDI_EVENT_DATA);

    switch (code) {
    case MCDI_EVENT_CODE_BADSSERT:
        netif_err(efx, hw, efx->net_dev,
              "MC watchdog or assertion failure at 0x%x\n", data);
        efx_mcdi_ev_death(efx, EINTR);
        break;

    case MCDI_EVENT_CODE_PMNOTICE:
        netif_info(efx, wol, efx->net_dev, "MCDI PM event.\n");
        break;

    case MCDI_EVENT_CODE_CMDDONE:
        efx_mcdi_ev_cpl(efx,
                MCDI_EVENT_FIELD(*event, CMDDONE_SEQ),
                MCDI_EVENT_FIELD(*event, CMDDONE_DATALEN),
                MCDI_EVENT_FIELD(*event, CMDDONE_ERRNO));
        break;

    case MCDI_EVENT_CODE_LINKCHANGE:
        efx_mcdi_process_link_change(efx, event);
        break;
    case MCDI_EVENT_CODE_SENSOREVT:
        efx_mcdi_sensor_event(efx, event);
        break;
    case MCDI_EVENT_CODE_SCHEDERR:
        netif_info(efx, hw, efx->net_dev,
               "MC Scheduler error address=0x%x\n", data);
        break;
    case MCDI_EVENT_CODE_REBOOT:
        netif_info(efx, hw, efx->net_dev, "MC Reboot\n");
        efx_mcdi_ev_death(efx, EIO);
        break;
    case MCDI_EVENT_CODE_MAC_STATS_DMA:
        /* MAC stats are gather lazily.  We can ignore this. */
        break;
    case MCDI_EVENT_CODE_FLR:
        efx_sriov_flr(efx, MCDI_EVENT_FIELD(*event, FLR_VF));
        break;
    case MCDI_EVENT_CODE_PTP_RX:
    case MCDI_EVENT_CODE_PTP_FAULT:
    case MCDI_EVENT_CODE_PTP_PPS:
        efx_ptp_event(efx, event);
        break;

    default:
        netif_err(efx, hw, efx->net_dev, "Unknown MCDI event 0x%x\n",
              code);
    }
}

/**************************************************************************
 *
 * Specific request functions
 *
 **************************************************************************
 */

void efx_mcdi_print_fwver(struct efx_nic *efx, char *buf, size_t len)
{
    u8 outbuf[ALIGN(MC_CMD_GET_VERSION_OUT_LEN, 4)];
    size_t outlength;
    const __le16 *ver_words;
    int rc;

    BUILD_BUG_ON(MC_CMD_GET_VERSION_IN_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_GET_VERSION, NULL, 0,
              outbuf, sizeof(outbuf), &outlength);
    if (rc)
        goto fail;

    if (outlength < MC_CMD_GET_VERSION_OUT_LEN) {
        rc = -EIO;
        goto fail;
    }

    ver_words = (__le16 *)MCDI_PTR(outbuf, GET_VERSION_OUT_VERSION);
    snprintf(buf, len, "%u.%u.%u.%u",
         le16_to_cpu(ver_words[0]), le16_to_cpu(ver_words[1]),
         le16_to_cpu(ver_words[2]), le16_to_cpu(ver_words[3]));
    return;

fail:
    netif_err(efx, probe, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    buf[0] = 0;
}

int efx_mcdi_drv_attach(struct efx_nic *efx, bool driver_operating,
            bool *was_attached)
{
    u8 inbuf[MC_CMD_DRV_ATTACH_IN_LEN];
    u8 outbuf[MC_CMD_DRV_ATTACH_OUT_LEN];
    size_t outlen;
    int rc;

    MCDI_SET_DWORD(inbuf, DRV_ATTACH_IN_NEW_STATE,
               driver_operating ? 1 : 0);
    MCDI_SET_DWORD(inbuf, DRV_ATTACH_IN_UPDATE, 1);

    rc = efx_mcdi_rpc(efx, MC_CMD_DRV_ATTACH, inbuf, sizeof(inbuf),
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;
    if (outlen < MC_CMD_DRV_ATTACH_OUT_LEN) {
        rc = -EIO;
        goto fail;
    }

    if (was_attached != NULL)
        *was_attached = MCDI_DWORD(outbuf, DRV_ATTACH_OUT_OLD_STATE);
    return 0;

fail:
    netif_err(efx, probe, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_get_board_cfg(struct efx_nic *efx, u8 *mac_address,
               u16 *fw_subtype_list, u32 *capabilities)
{
    uint8_t outbuf[MC_CMD_GET_BOARD_CFG_OUT_LENMIN];
    size_t outlen, offset, i;
    int port_num = efx_port_num(efx);
    int rc;

    BUILD_BUG_ON(MC_CMD_GET_BOARD_CFG_IN_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_GET_BOARD_CFG, NULL, 0,
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;

    if (outlen < MC_CMD_GET_BOARD_CFG_OUT_LENMIN) {
        rc = -EIO;
        goto fail;
    }

    offset = (port_num)
        ? MC_CMD_GET_BOARD_CFG_OUT_MAC_ADDR_BASE_PORT1_OFST
        : MC_CMD_GET_BOARD_CFG_OUT_MAC_ADDR_BASE_PORT0_OFST;
    if (mac_address)
        memcpy(mac_address, outbuf + offset, ETH_ALEN);
    if (fw_subtype_list) {
        /* Byte-swap and truncate or zero-pad as necessary */
        offset = MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_OFST;
        for (i = 0;
             i < MC_CMD_GET_BOARD_CFG_OUT_FW_SUBTYPE_LIST_MAXNUM;
             i++) {
            fw_subtype_list[i] =
                (offset + 2 <= outlen) ?
                le16_to_cpup((__le16 *)(outbuf + offset)) : 0;
            offset += 2;
        }
    }
    if (capabilities) {
        if (port_num)
            *capabilities = MCDI_DWORD(outbuf,
                    GET_BOARD_CFG_OUT_CAPABILITIES_PORT1);
        else
            *capabilities = MCDI_DWORD(outbuf,
                    GET_BOARD_CFG_OUT_CAPABILITIES_PORT0);
    }

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d len=%d\n",
          __func__, rc, (int)outlen);

    return rc;
}

int efx_mcdi_log_ctrl(struct efx_nic *efx, bool evq, bool uart, u32 dest_evq)
{
    u8 inbuf[MC_CMD_LOG_CTRL_IN_LEN];
    u32 dest = 0;
    int rc;

    if (uart)
        dest |= MC_CMD_LOG_CTRL_IN_LOG_DEST_UART;
    if (evq)
        dest |= MC_CMD_LOG_CTRL_IN_LOG_DEST_EVQ;

    MCDI_SET_DWORD(inbuf, LOG_CTRL_IN_LOG_DEST, dest);
    MCDI_SET_DWORD(inbuf, LOG_CTRL_IN_LOG_DEST_EVQ, dest_evq);

    BUILD_BUG_ON(MC_CMD_LOG_CTRL_OUT_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_LOG_CTRL, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_nvram_types(struct efx_nic *efx, u32 *nvram_types_out)
{
    u8 outbuf[MC_CMD_NVRAM_TYPES_OUT_LEN];
    size_t outlen;
    int rc;

    BUILD_BUG_ON(MC_CMD_NVRAM_TYPES_IN_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_TYPES, NULL, 0,
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;
    if (outlen < MC_CMD_NVRAM_TYPES_OUT_LEN) {
        rc = -EIO;
        goto fail;
    }

    *nvram_types_out = MCDI_DWORD(outbuf, NVRAM_TYPES_OUT_TYPES);
    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n",
          __func__, rc);
    return rc;
}

int efx_mcdi_nvram_info(struct efx_nic *efx, unsigned int type,
            size_t *size_out, size_t *erase_size_out,
            bool *protected_out)
{
    u8 inbuf[MC_CMD_NVRAM_INFO_IN_LEN];
    u8 outbuf[MC_CMD_NVRAM_INFO_OUT_LEN];
    size_t outlen;
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_INFO_IN_TYPE, type);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_INFO, inbuf, sizeof(inbuf),
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;
    if (outlen < MC_CMD_NVRAM_INFO_OUT_LEN) {
        rc = -EIO;
        goto fail;
    }

    *size_out = MCDI_DWORD(outbuf, NVRAM_INFO_OUT_SIZE);
    *erase_size_out = MCDI_DWORD(outbuf, NVRAM_INFO_OUT_ERASESIZE);
    *protected_out = !!(MCDI_DWORD(outbuf, NVRAM_INFO_OUT_FLAGS) &
                (1 << MC_CMD_NVRAM_INFO_OUT_PROTECTED_LBN));
    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_nvram_update_start(struct efx_nic *efx, unsigned int type)
{
    u8 inbuf[MC_CMD_NVRAM_UPDATE_START_IN_LEN];
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_UPDATE_START_IN_TYPE, type);

    BUILD_BUG_ON(MC_CMD_NVRAM_UPDATE_START_OUT_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_UPDATE_START, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_nvram_read(struct efx_nic *efx, unsigned int type,
            loff_t offset, u8 *buffer, size_t length)
{
    u8 inbuf[MC_CMD_NVRAM_READ_IN_LEN];
    u8 outbuf[MC_CMD_NVRAM_READ_OUT_LEN(EFX_MCDI_NVRAM_LEN_MAX)];
    size_t outlen;
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_READ_IN_TYPE, type);
    MCDI_SET_DWORD(inbuf, NVRAM_READ_IN_OFFSET, offset);
    MCDI_SET_DWORD(inbuf, NVRAM_READ_IN_LENGTH, length);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_READ, inbuf, sizeof(inbuf),
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;

    memcpy(buffer, MCDI_PTR(outbuf, NVRAM_READ_OUT_READ_BUFFER), length);
    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_nvram_write(struct efx_nic *efx, unsigned int type,
               loff_t offset, const u8 *buffer, size_t length)
{
    u8 inbuf[MC_CMD_NVRAM_WRITE_IN_LEN(EFX_MCDI_NVRAM_LEN_MAX)];
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_WRITE_IN_TYPE, type);
    MCDI_SET_DWORD(inbuf, NVRAM_WRITE_IN_OFFSET, offset);
    MCDI_SET_DWORD(inbuf, NVRAM_WRITE_IN_LENGTH, length);
    memcpy(MCDI_PTR(inbuf, NVRAM_WRITE_IN_WRITE_BUFFER), buffer, length);

    BUILD_BUG_ON(MC_CMD_NVRAM_WRITE_OUT_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_WRITE, inbuf,
              ALIGN(MC_CMD_NVRAM_WRITE_IN_LEN(length), 4),
              NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_nvram_erase(struct efx_nic *efx, unsigned int type,
             loff_t offset, size_t length)
{
    u8 inbuf[MC_CMD_NVRAM_ERASE_IN_LEN];
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_ERASE_IN_TYPE, type);
    MCDI_SET_DWORD(inbuf, NVRAM_ERASE_IN_OFFSET, offset);
    MCDI_SET_DWORD(inbuf, NVRAM_ERASE_IN_LENGTH, length);

    BUILD_BUG_ON(MC_CMD_NVRAM_ERASE_OUT_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_ERASE, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_nvram_update_finish(struct efx_nic *efx, unsigned int type)
{
    u8 inbuf[MC_CMD_NVRAM_UPDATE_FINISH_IN_LEN];
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_UPDATE_FINISH_IN_TYPE, type);

    BUILD_BUG_ON(MC_CMD_NVRAM_UPDATE_FINISH_OUT_LEN != 0);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_UPDATE_FINISH, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

static int efx_mcdi_nvram_test(struct efx_nic *efx, unsigned int type)
{
    u8 inbuf[MC_CMD_NVRAM_TEST_IN_LEN];
    u8 outbuf[MC_CMD_NVRAM_TEST_OUT_LEN];
    int rc;

    MCDI_SET_DWORD(inbuf, NVRAM_TEST_IN_TYPE, type);

    rc = efx_mcdi_rpc(efx, MC_CMD_NVRAM_TEST, inbuf, sizeof(inbuf),
              outbuf, sizeof(outbuf), NULL);
    if (rc)
        return rc;

    switch (MCDI_DWORD(outbuf, NVRAM_TEST_OUT_RESULT)) {
    case MC_CMD_NVRAM_TEST_PASS:
    case MC_CMD_NVRAM_TEST_NOTSUPP:
        return 0;
    default:
        return -EIO;
    }
}

int efx_mcdi_nvram_test_all(struct efx_nic *efx)
{
    u32 nvram_types;
    unsigned int type;
    int rc;

    rc = efx_mcdi_nvram_types(efx, &nvram_types);
    if (rc)
        goto fail1;

    type = 0;
    while (nvram_types != 0) {
        if (nvram_types & 1) {
            rc = efx_mcdi_nvram_test(efx, type);
            if (rc)
                goto fail2;
        }
        type++;
        nvram_types >>= 1;
    }

    return 0;

fail2:
    netif_err(efx, hw, efx->net_dev, "%s: failed type=%u\n",
          __func__, type);
fail1:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

static int efx_mcdi_read_assertion(struct efx_nic *efx)
{
    u8 inbuf[MC_CMD_GET_ASSERTS_IN_LEN];
    u8 outbuf[MC_CMD_GET_ASSERTS_OUT_LEN];
    unsigned int flags, index, ofst;
    const char *reason;
    size_t outlen;
    int retry;
    int rc;

    /* Attempt to read any stored assertion state before we reboot
     * the mcfw out of the assertion handler. Retry twice, once
     * because a boot-time assertion might cause this command to fail
     * with EINTR. And once again because GET_ASSERTS can race with
     * MC_CMD_REBOOT running on the other port. */
    retry = 2;
    do {
        MCDI_SET_DWORD(inbuf, GET_ASSERTS_IN_CLEAR, 1);
        rc = efx_mcdi_rpc(efx, MC_CMD_GET_ASSERTS,
                  inbuf, MC_CMD_GET_ASSERTS_IN_LEN,
                  outbuf, sizeof(outbuf), &outlen);
    } while ((rc == -EINTR || rc == -EIO) && retry-- > 0);

    if (rc)
        return rc;
    if (outlen < MC_CMD_GET_ASSERTS_OUT_LEN)
        return -EIO;

    /* Print out any recorded assertion state */
    flags = MCDI_DWORD(outbuf, GET_ASSERTS_OUT_GLOBAL_FLAGS);
    if (flags == MC_CMD_GET_ASSERTS_FLAGS_NO_FAILS)
        return 0;

    reason = (flags == MC_CMD_GET_ASSERTS_FLAGS_SYS_FAIL)
        ? "system-level assertion"
        : (flags == MC_CMD_GET_ASSERTS_FLAGS_THR_FAIL)
        ? "thread-level assertion"
        : (flags == MC_CMD_GET_ASSERTS_FLAGS_WDOG_FIRED)
        ? "watchdog reset"
        : "unknown assertion";
    netif_err(efx, hw, efx->net_dev,
          "MCPU %s at PC = 0x%.8x in thread 0x%.8x\n", reason,
          MCDI_DWORD(outbuf, GET_ASSERTS_OUT_SAVED_PC_OFFS),
          MCDI_DWORD(outbuf, GET_ASSERTS_OUT_THREAD_OFFS));

    /* Print out the registers */
    ofst = MC_CMD_GET_ASSERTS_OUT_GP_REGS_OFFS_OFST;
    for (index = 1; index < 32; index++) {
        netif_err(efx, hw, efx->net_dev, "R%.2d (?): 0x%.8x\n", index,
            MCDI_DWORD2(outbuf, ofst));
        ofst += sizeof(efx_dword_t);
    }

    return 0;
}

static void efx_mcdi_exit_assertion(struct efx_nic *efx)
{
    u8 inbuf[MC_CMD_REBOOT_IN_LEN];

    /* If the MC is running debug firmware, it might now be
     * waiting for a debugger to attach, but we just want it to
     * reboot.  We set a flag that makes the command a no-op if it
     * has already done so.  We don't know what return code to
     * expect (0 or -EIO), so ignore it.
     */
    BUILD_BUG_ON(MC_CMD_REBOOT_OUT_LEN != 0);
    MCDI_SET_DWORD(inbuf, REBOOT_IN_FLAGS,
               MC_CMD_REBOOT_FLAGS_AFTER_ASSERTION);
    (void) efx_mcdi_rpc(efx, MC_CMD_REBOOT, inbuf, MC_CMD_REBOOT_IN_LEN,
                NULL, 0, NULL);
}

int efx_mcdi_handle_assertion(struct efx_nic *efx)
{
    int rc;

    rc = efx_mcdi_read_assertion(efx);
    if (rc)
        return rc;

    efx_mcdi_exit_assertion(efx);

    return 0;
}

void efx_mcdi_set_id_led(struct efx_nic *efx, enum efx_led_mode mode)
{
    u8 inbuf[MC_CMD_SET_ID_LED_IN_LEN];
    int rc;

    BUILD_BUG_ON(EFX_LED_OFF != MC_CMD_LED_OFF);
    BUILD_BUG_ON(EFX_LED_ON != MC_CMD_LED_ON);
    BUILD_BUG_ON(EFX_LED_DEFAULT != MC_CMD_LED_DEFAULT);

    BUILD_BUG_ON(MC_CMD_SET_ID_LED_OUT_LEN != 0);

    MCDI_SET_DWORD(inbuf, SET_ID_LED_IN_STATE, mode);

    rc = efx_mcdi_rpc(efx, MC_CMD_SET_ID_LED, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    if (rc)
        netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n",
              __func__, rc);
}

int efx_mcdi_reset_port(struct efx_nic *efx)
{
    int rc = efx_mcdi_rpc(efx, MC_CMD_ENTITY_RESET, NULL, 0, NULL, 0, NULL);
    if (rc)
        netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n",
              __func__, rc);
    return rc;
}

int efx_mcdi_reset_mc(struct efx_nic *efx)
{
    u8 inbuf[MC_CMD_REBOOT_IN_LEN];
    int rc;

    BUILD_BUG_ON(MC_CMD_REBOOT_OUT_LEN != 0);
    MCDI_SET_DWORD(inbuf, REBOOT_IN_FLAGS, 0);
    rc = efx_mcdi_rpc(efx, MC_CMD_REBOOT, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    /* White is black, and up is down */
    if (rc == -EIO)
        return 0;
    if (rc == 0)
        rc = -EIO;
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

static int efx_mcdi_wol_filter_set(struct efx_nic *efx, u32 type,
                   const u8 *mac, int *id_out)
{
    u8 inbuf[MC_CMD_WOL_FILTER_SET_IN_LEN];
    u8 outbuf[MC_CMD_WOL_FILTER_SET_OUT_LEN];
    size_t outlen;
    int rc;

    MCDI_SET_DWORD(inbuf, WOL_FILTER_SET_IN_WOL_TYPE, type);
    MCDI_SET_DWORD(inbuf, WOL_FILTER_SET_IN_FILTER_MODE,
               MC_CMD_FILTER_MODE_SIMPLE);
    memcpy(MCDI_PTR(inbuf, WOL_FILTER_SET_IN_MAGIC_MAC), mac, ETH_ALEN);

    rc = efx_mcdi_rpc(efx, MC_CMD_WOL_FILTER_SET, inbuf, sizeof(inbuf),
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;

    if (outlen < MC_CMD_WOL_FILTER_SET_OUT_LEN) {
        rc = -EIO;
        goto fail;
    }

    *id_out = (int)MCDI_DWORD(outbuf, WOL_FILTER_SET_OUT_FILTER_ID);

    return 0;

fail:
    *id_out = -1;
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;

}


int
efx_mcdi_wol_filter_set_magic(struct efx_nic *efx,  const u8 *mac, int *id_out)
{
    return efx_mcdi_wol_filter_set(efx, MC_CMD_WOL_TYPE_MAGIC, mac, id_out);
}


int efx_mcdi_wol_filter_get_magic(struct efx_nic *efx, int *id_out)
{
    u8 outbuf[MC_CMD_WOL_FILTER_GET_OUT_LEN];
    size_t outlen;
    int rc;

    rc = efx_mcdi_rpc(efx, MC_CMD_WOL_FILTER_GET, NULL, 0,
              outbuf, sizeof(outbuf), &outlen);
    if (rc)
        goto fail;

    if (outlen < MC_CMD_WOL_FILTER_GET_OUT_LEN) {
        rc = -EIO;
        goto fail;
    }

    *id_out = (int)MCDI_DWORD(outbuf, WOL_FILTER_GET_OUT_FILTER_ID);

    return 0;

fail:
    *id_out = -1;
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}


int efx_mcdi_wol_filter_remove(struct efx_nic *efx, int id)
{
    u8 inbuf[MC_CMD_WOL_FILTER_REMOVE_IN_LEN];
    int rc;

    MCDI_SET_DWORD(inbuf, WOL_FILTER_REMOVE_IN_FILTER_ID, (u32)id);

    rc = efx_mcdi_rpc(efx, MC_CMD_WOL_FILTER_REMOVE, inbuf, sizeof(inbuf),
              NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}

int efx_mcdi_flush_rxqs(struct efx_nic *efx)
{
    struct efx_channel *channel;
    struct efx_rx_queue *rx_queue;
    __le32 *qid;
    int rc, count;

    BUILD_BUG_ON(EFX_MAX_CHANNELS >
             MC_CMD_FLUSH_RX_QUEUES_IN_QID_OFST_MAXNUM);

    qid = kmalloc(EFX_MAX_CHANNELS * sizeof(*qid), GFP_KERNEL);
    if (qid == NULL)
        return -ENOMEM;

    count = 0;
    efx_for_each_channel(channel, efx) {
        efx_for_each_channel_rx_queue(rx_queue, channel) {
            if (rx_queue->flush_pending) {
                rx_queue->flush_pending = false;
                atomic_dec(&efx->rxq_flush_pending);
                qid[count++] = cpu_to_le32(
                    efx_rx_queue_index(rx_queue));
            }
        }
    }

    rc = efx_mcdi_rpc(efx, MC_CMD_FLUSH_RX_QUEUES, (u8 *)qid,
              count * sizeof(*qid), NULL, 0, NULL);
    WARN_ON(rc > 0);

    kfree(qid);

    return rc;
}

int efx_mcdi_wol_filter_reset(struct efx_nic *efx)
{
    int rc;

    rc = efx_mcdi_rpc(efx, MC_CMD_WOL_FILTER_RESET, NULL, 0, NULL, 0, NULL);
    if (rc)
        goto fail;

    return 0;

fail:
    netif_err(efx, hw, efx->net_dev, "%s: failed rc=%d\n", __func__, rc);
    return rc;
}