/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2005-2006 Fen Systems Ltd.
 * Copyright 2006-2012 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/netdevice.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/kernel_stat.h>
#include <linux/pci.h>
#include <linux/ethtool.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/udp.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
#include "selftest.h"
#include "workarounds.h"

/* IRQ latency can be enormous because:
 * - All IRQs may be disabled on a CPU for a *long* time by e.g. a
 *   slow serial console or an old IDE driver doing error recovery
 * - The PREEMPT_RT patches mostly deal with this, but also allow a
 *   tasklet or normal task to be given higher priority than our IRQ
 *   threads
 * Try to avoid blaming the hardware for this.
 */
#define IRQ_TIMEOUT HZ

/*
 * Loopback test packet structure
 *
 * The self-test should stress every RSS vector, and unfortunately
 * Falcon only performs RSS on TCP/UDP packets.
 */
struct efx_loopback_payload {
        struct ethhdr header;
        struct iphdr ip;
        struct udphdr udp;
        __be16 iteration;
        char msg[64];
} __packed;

/* Loopback test source MAC address */
static const u8 payload_source[ETH_ALEN] __aligned(2) = {
        0x00, 0x0f, 0x53, 0x1b, 0x1b, 0x1b,
};

static const char payload_msg[] =
        "Hello world! This is an Efx loopback test in progress!";

/* Interrupt mode names */
static const unsigned int efx_interrupt_mode_max = EFX_INT_MODE_MAX;
static const char *const efx_interrupt_mode_names[] = {
        [EFX_INT_MODE_MSIX]   = "MSI-X",
        [EFX_INT_MODE_MSI]    = "MSI",
        [EFX_INT_MODE_LEGACY] = "legacy",
};
#define INT_MODE(efx) \
        STRING_TABLE_LOOKUP(efx->interrupt_mode, efx_interrupt_mode)

/**
 * efx_loopback_state - persistent state during a loopback selftest
 * @flush:              Drop all packets in efx_loopback_rx_packet
 * @packet_count:       Number of packets being used in this test
 * @skbs:               An array of skbs transmitted
 * @offload_csum:       Checksums are being offloaded
 * @rx_good:            RX good packet count
 * @rx_bad:             RX bad packet count
 * @payload:            Payload used in tests
 */
struct efx_loopback_state {
        bool flush;
        int packet_count;
        struct sk_buff **skbs;
        bool offload_csum;
        atomic_t rx_good;
        atomic_t rx_bad;
        struct efx_loopback_payload payload;
};

/* How long to wait for all the packets to arrive (in ms) */
#define LOOPBACK_TIMEOUT_MS 1000

/**************************************************************************
 *
 * MII, NVRAM and register tests
 *
 **************************************************************************/

static int efx_test_phy_alive(struct efx_nic *efx, struct efx_self_tests *tests)
{
        int rc = 0;

        if (efx->phy_op->test_alive) {
                rc = efx->phy_op->test_alive(efx);
                tests->phy_alive = rc ? -1 : 1;
        }

        return rc;
}

static int efx_test_nvram(struct efx_nic *efx, struct efx_self_tests *tests)
{
        int rc = 0;

        if (efx->type->test_nvram) {
                rc = efx->type->test_nvram(efx);
                tests->nvram = rc ? -1 : 1;
        }

        return rc;
}

/**************************************************************************
 *
 * Interrupt and event queue testing
 *
 **************************************************************************/

/* Test generation and receipt of interrupts */
static int efx_test_interrupts(struct efx_nic *efx,
                               struct efx_self_tests *tests)
{
        unsigned long timeout, wait;
        int cpu;

        netif_dbg(efx, drv, efx->net_dev, "testing interrupts\n");
        tests->interrupt = -1;

        efx_nic_irq_test_start(efx);
        timeout = jiffies + IRQ_TIMEOUT;
        wait = 1;

        /* Wait for arrival of test interrupt. */
        netif_dbg(efx, drv, efx->net_dev, "waiting for test interrupt\n");
        do {
                schedule_timeout_uninterruptible(wait);
                cpu = efx_nic_irq_test_irq_cpu(efx);
                if (cpu >= 0)
                        goto success;
                wait *= 2;
        } while (time_before(jiffies, timeout));

        netif_err(efx, drv, efx->net_dev, "timed out waiting for interrupt\n");
        return -ETIMEDOUT;

 success:
        netif_dbg(efx, drv, efx->net_dev, "%s test interrupt seen on CPU%d\n",
                  INT_MODE(efx), cpu);
        tests->interrupt = 1;
        return 0;
}

/* Test generation and receipt of interrupting events */
static int efx_test_eventq_irq(struct efx_nic *efx,
                               struct efx_self_tests *tests)
{
        struct efx_channel *channel;
        unsigned int read_ptr[EFX_MAX_CHANNELS];
        unsigned long napi_ran = 0, dma_pend = 0, int_pend = 0;
        unsigned long timeout, wait;

        BUILD_BUG_ON(EFX_MAX_CHANNELS > BITS_PER_LONG);

        efx_for_each_channel(channel, efx) {
                read_ptr[channel->channel] = channel->eventq_read_ptr;
                set_bit(channel->channel, &dma_pend);
                set_bit(channel->channel, &int_pend);
                efx_nic_event_test_start(channel);
        }

        timeout = jiffies + IRQ_TIMEOUT;
        wait = 1;

        /* Wait for arrival of interrupts.  NAPI processing may or may
         * not complete in time, but we can cope in any case.
         */
        do {
                schedule_timeout_uninterruptible(wait);

                efx_for_each_channel(channel, efx) {
                        efx_stop_eventq(channel);
                        if (channel->eventq_read_ptr !=
                            read_ptr[channel->channel]) {
                                set_bit(channel->channel, &napi_ran);
                                clear_bit(channel->channel, &dma_pend);
                                clear_bit(channel->channel, &int_pend);
                        } else {
                                if (efx_nic_event_present(channel))
                                        clear_bit(channel->channel, &dma_pend);
                                if (efx_nic_event_test_irq_cpu(channel) >= 0)
                                        clear_bit(channel->channel, &int_pend);
                        }
                        efx_start_eventq(channel);
                }

                wait *= 2;
        } while ((dma_pend || int_pend) && time_before(jiffies, timeout));

        efx_for_each_channel(channel, efx) {
                bool dma_seen = !test_bit(channel->channel, &dma_pend);
                bool int_seen = !test_bit(channel->channel, &int_pend);

                tests->eventq_dma[channel->channel] = dma_seen ? 1 : -1;
                tests->eventq_int[channel->channel] = int_seen ? 1 : -1;

                if (dma_seen && int_seen) {
                        netif_dbg(efx, drv, efx->net_dev,
                                  "channel %d event queue passed (with%s NAPI)\n",
                                  channel->channel,
                                  test_bit(channel->channel, &napi_ran) ?
                                  "" : "out");
                } else {
                        /* Report failure and whether either interrupt or DMA
                         * worked
                         */
                        netif_err(efx, drv, efx->net_dev,
                                  "channel %d timed out waiting for event queue\n",
                                  channel->channel);
                        if (int_seen)
                                netif_err(efx, drv, efx->net_dev,
                                          "channel %d saw interrupt "
                                          "during event queue test\n",
                                          channel->channel);
                        if (dma_seen)
                                netif_err(efx, drv, efx->net_dev,
                                          "channel %d event was generated, but "
                                          "failed to trigger an interrupt\n",
                                          channel->channel);
                }
        }

        return (dma_pend || int_pend) ? -ETIMEDOUT : 0;
}

static int efx_test_phy(struct efx_nic *efx, struct efx_self_tests *tests,
                        unsigned flags)
{
        int rc;

        if (!efx->phy_op->run_tests)
                return 0;

        mutex_lock(&efx->mac_lock);
        rc = efx->phy_op->run_tests(efx, tests->phy_ext, flags);
        mutex_unlock(&efx->mac_lock);
        return rc;
}

/**************************************************************************
 *
 * Loopback testing
 * NB Only one loopback test can be executing concurrently.
 *
 **************************************************************************/

/* Loopback test RX callback
 * This is called for each received packet during loopback testing.
 */
void efx_loopback_rx_packet(struct efx_nic *efx,
                            const char *buf_ptr, int pkt_len)
{
        struct efx_loopback_state *state = efx->loopback_selftest;
        struct efx_loopback_payload *received;
        struct efx_loopback_payload *payload;

        BUG_ON(!buf_ptr);

        /* If we are just flushing, then drop the packet */
        if ((state == NULL) || state->flush)
                return;

        payload = &state->payload;

        received = (struct efx_loopback_payload *) buf_ptr;
        received->ip.saddr = payload->ip.saddr;
        if (state->offload_csum)
                received->ip.check = payload->ip.check;

        /* Check that header exists */
        if (pkt_len < sizeof(received->header)) {
                netif_err(efx, drv, efx->net_dev,
                          "saw runt RX packet (length %d) in %s loopback "
                          "test\n", pkt_len, LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that the ethernet header exists */
        if (memcmp(&received->header, &payload->header, ETH_HLEN) != 0) {
                netif_err(efx, drv, efx->net_dev,
                          "saw non-loopback RX packet in %s loopback test\n",
                          LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check packet length */
        if (pkt_len != sizeof(*payload)) {
                netif_err(efx, drv, efx->net_dev,
                          "saw incorrect RX packet length %d (wanted %d) in "
                          "%s loopback test\n", pkt_len, (int)sizeof(*payload),
                          LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that IP header matches */
        if (memcmp(&received->ip, &payload->ip, sizeof(payload->ip)) != 0) {
                netif_err(efx, drv, efx->net_dev,
                          "saw corrupted IP header in %s loopback test\n",
                          LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that msg and padding matches */
        if (memcmp(&received->msg, &payload->msg, sizeof(received->msg)) != 0) {
                netif_err(efx, drv, efx->net_dev,
                          "saw corrupted RX packet in %s loopback test\n",
                          LOOPBACK_MODE(efx));
                goto err;
        }

        /* Check that iteration matches */
        if (received->iteration != payload->iteration) {
                netif_err(efx, drv, efx->net_dev,
                          "saw RX packet from iteration %d (wanted %d) in "
                          "%s loopback test\n", ntohs(received->iteration),
                          ntohs(payload->iteration), LOOPBACK_MODE(efx));
                goto err;
        }

        /* Increase correct RX count */
        netif_vdbg(efx, drv, efx->net_dev,
                   "got loopback RX in %s loopback test\n", LOOPBACK_MODE(efx));

        atomic_inc(&state->rx_good);
        return;

 err:
#ifdef DEBUG
        if (atomic_read(&state->rx_bad) == 0) {
                netif_err(efx, drv, efx->net_dev, "received packet:\n");
                print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
                               buf_ptr, pkt_len, 0);
                netif_err(efx, drv, efx->net_dev, "expected packet:\n");
                print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
                               &state->payload, sizeof(state->payload), 0);
        }
#endif
        atomic_inc(&state->rx_bad);
}

/* Initialise an efx_selftest_state for a new iteration */
static void efx_iterate_state(struct efx_nic *efx)
{
        struct efx_loopback_state *state = efx->loopback_selftest;
        struct net_device *net_dev = efx->net_dev;
        struct efx_loopback_payload *payload = &state->payload;

        /* Initialise the layerII header */
        ether_addr_copy((u8 *)&payload->header.h_dest, net_dev->dev_addr);
        ether_addr_copy((u8 *)&payload->header.h_source, payload_source);
        payload->header.h_proto = htons(ETH_P_IP);

        /* saddr set later and used as incrementing count */
        payload->ip.daddr = htonl(INADDR_LOOPBACK);
        payload->ip.ihl = 5;
        payload->ip.check = (__force __sum16) htons(0xdead);
        payload->ip.tot_len = htons(sizeof(*payload) - sizeof(struct ethhdr));
        payload->ip.version = IPVERSION;
        payload->ip.protocol = IPPROTO_UDP;

        /* Initialise udp header */
        payload->udp.source = 0;
        payload->udp.len = htons(sizeof(*payload) - sizeof(struct ethhdr) -
                                 sizeof(struct iphdr));
        payload->udp.check = 0; /* checksum ignored */

        /* Fill out payload */
        payload->iteration = htons(ntohs(payload->iteration) + 1);
        memcpy(&payload->msg, payload_msg, sizeof(payload_msg));

        /* Fill out remaining state members */
        atomic_set(&state->rx_good, 0);
        atomic_set(&state->rx_bad, 0);
        smp_wmb();
}

static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
{
        struct efx_nic *efx = tx_queue->efx;
        struct efx_loopback_state *state = efx->loopback_selftest;
        struct efx_loopback_payload *payload;
        struct sk_buff *skb;
        int i;
        netdev_tx_t rc;

        /* Transmit N copies of buffer */
        for (i = 0; i < state->packet_count; i++) {
                /* Allocate an skb, holding an extra reference for
                 * transmit completion counting */
                skb = alloc_skb(sizeof(state->payload), GFP_KERNEL);
                if (!skb)
                        return -ENOMEM;
                state->skbs[i] = skb;
                skb_get(skb);

                /* Copy the payload in, incrementing the source address to
                 * exercise the rss vectors */
                payload = ((struct efx_loopback_payload *)
                           skb_put(skb, sizeof(state->payload)));
                memcpy(payload, &state->payload, sizeof(state->payload));
                payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));

                /* Ensure everything we've written is visible to the
                 * interrupt handler. */
                smp_wmb();

                netif_tx_lock_bh(efx->net_dev);
                rc = efx_enqueue_skb(tx_queue, skb);
                netif_tx_unlock_bh(efx->net_dev);

                if (rc != NETDEV_TX_OK) {
                        netif_err(efx, drv, efx->net_dev,
                                  "TX queue %d could not transmit packet %d of "
                                  "%d in %s loopback test\n", tx_queue->queue,
                                  i + 1, state->packet_count,
                                  LOOPBACK_MODE(efx));

                        /* Defer cleaning up the other skbs for the caller */
                        kfree_skb(skb);
                        return -EPIPE;
                }
        }

        return 0;
}

static int efx_poll_loopback(struct efx_nic *efx)
{
        struct efx_loopback_state *state = efx->loopback_selftest;

        return atomic_read(&state->rx_good) == state->packet_count;
}

static int efx_end_loopback(struct efx_tx_queue *tx_queue,
                            struct efx_loopback_self_tests *lb_tests)
{
        struct efx_nic *efx = tx_queue->efx;
        struct efx_loopback_state *state = efx->loopback_selftest;
        struct sk_buff *skb;
        int tx_done = 0, rx_good, rx_bad;
        int i, rc = 0;

        netif_tx_lock_bh(efx->net_dev);

        /* Count the number of tx completions, and decrement the refcnt. Any
         * skbs not already completed will be free'd when the queue is flushed */
        for (i = 0; i < state->packet_count; i++) {
                skb = state->skbs[i];
                if (skb && !skb_shared(skb))
                        ++tx_done;
                dev_kfree_skb(skb);
        }

        netif_tx_unlock_bh(efx->net_dev);

        /* Check TX completion and received packet counts */
        rx_good = atomic_read(&state->rx_good);
        rx_bad = atomic_read(&state->rx_bad);
        if (tx_done != state->packet_count) {
                /* Don't free the skbs; they will be picked up on TX
                 * overflow or channel teardown.
                 */
                netif_err(efx, drv, efx->net_dev,
                          "TX queue %d saw only %d out of an expected %d "
                          "TX completion events in %s loopback test\n",
                          tx_queue->queue, tx_done, state->packet_count,
                          LOOPBACK_MODE(efx));
                rc = -ETIMEDOUT;
                /* Allow to fall through so we see the RX errors as well */
        }

        /* We may always be up to a flush away from our desired packet total */
        if (rx_good != state->packet_count) {
                netif_dbg(efx, drv, efx->net_dev,
                          "TX queue %d saw only %d out of an expected %d "
                          "received packets in %s loopback test\n",
                          tx_queue->queue, rx_good, state->packet_count,
                          LOOPBACK_MODE(efx));
                rc = -ETIMEDOUT;
                /* Fall through */
        }

        /* Update loopback test structure */
        lb_tests->tx_sent[tx_queue->queue] += state->packet_count;
        lb_tests->tx_done[tx_queue->queue] += tx_done;
        lb_tests->rx_good += rx_good;
        lb_tests->rx_bad += rx_bad;

        return rc;
}

static int
efx_test_loopback(struct efx_tx_queue *tx_queue,
                  struct efx_loopback_self_tests *lb_tests)
{
        struct efx_nic *efx = tx_queue->efx;
        struct efx_loopback_state *state = efx->loopback_selftest;
        int i, begin_rc, end_rc;

        for (i = 0; i < 3; i++) {
                /* Determine how many packets to send */
                state->packet_count = efx->txq_entries / 3;
                state->packet_count = min(1 << (i << 2), state->packet_count);
                state->skbs = kcalloc(state->packet_count,
                                      sizeof(state->skbs[0]), GFP_KERNEL);
                if (!state->skbs)
                        return -ENOMEM;
                state->flush = false;

                netif_dbg(efx, drv, efx->net_dev,
                          "TX queue %d testing %s loopback with %d packets\n",
                          tx_queue->queue, LOOPBACK_MODE(efx),
                          state->packet_count);

                efx_iterate_state(efx);
                begin_rc = efx_begin_loopback(tx_queue);

                /* This will normally complete very quickly, but be
                 * prepared to wait much longer. */
                msleep(1);
                if (!efx_poll_loopback(efx)) {
                        msleep(LOOPBACK_TIMEOUT_MS);
                        efx_poll_loopback(efx);
                }

                end_rc = efx_end_loopback(tx_queue, lb_tests);
                kfree(state->skbs);

                if (begin_rc || end_rc) {
                        /* Wait a while to ensure there are no packets
                         * floating around after a failure. */
                        schedule_timeout_uninterruptible(HZ / 10);
                        return begin_rc ? begin_rc : end_rc;
                }
        }

        netif_dbg(efx, drv, efx->net_dev,
                  "TX queue %d passed %s loopback test with a burst length "
                  "of %d packets\n", tx_queue->queue, LOOPBACK_MODE(efx),
                  state->packet_count);

        return 0;
}

/* Wait for link up. On Falcon, we would prefer to rely on efx_monitor, but
 * any contention on the mac lock (via e.g. efx_mac_mcast_work) causes it
 * to delay and retry. Therefore, it's safer to just poll directly. Wait
 * for link up and any faults to dissipate. */
static int efx_wait_for_link(struct efx_nic *efx)
{
        struct efx_link_state *link_state = &efx->link_state;
        int count, link_up_count = 0;
        bool link_up;

        for (count = 0; count < 40; count++) {
                schedule_timeout_uninterruptible(HZ / 10);

                if (efx->type->monitor != NULL) {
                        mutex_lock(&efx->mac_lock);
                        efx->type->monitor(efx);
                        mutex_unlock(&efx->mac_lock);
                }

                mutex_lock(&efx->mac_lock);
                link_up = link_state->up;
                if (link_up)
                        link_up = !efx->type->check_mac_fault(efx);
                mutex_unlock(&efx->mac_lock);

                if (link_up) {
                        if (++link_up_count == 2)
                                return 0;
                } else {
                        link_up_count = 0;
                }
        }

        return -ETIMEDOUT;
}

static int efx_test_loopbacks(struct efx_nic *efx, struct efx_self_tests *tests,
                              unsigned int loopback_modes)
{
        enum efx_loopback_mode mode;
        struct efx_loopback_state *state;
        struct efx_channel *channel =
                efx_get_channel(efx, efx->tx_channel_offset);
        struct efx_tx_queue *tx_queue;
        int rc = 0;

        /* Set the port loopback_selftest member. From this point on
         * all received packets will be dropped. Mark the state as
         * "flushing" so all inflight packets are dropped */
        state = kzalloc(sizeof(*state), GFP_KERNEL);
        if (state == NULL)
                return -ENOMEM;
        BUG_ON(efx->loopback_selftest);
        state->flush = true;
        efx->loopback_selftest = state;

        /* Test all supported loopback modes */
        for (mode = LOOPBACK_NONE; mode <= LOOPBACK_TEST_MAX; mode++) {
                if (!(loopback_modes & (1 << mode)))
                        continue;

                /* Move the port into the specified loopback mode. */
                state->flush = true;
                mutex_lock(&efx->mac_lock);
                efx->loopback_mode = mode;
                rc = __efx_reconfigure_port(efx);
                mutex_unlock(&efx->mac_lock);
                if (rc) {
                        netif_err(efx, drv, efx->net_dev,
                                  "unable to move into %s loopback\n",
                                  LOOPBACK_MODE(efx));
                        goto out;
                }

                rc = efx_wait_for_link(efx);
                if (rc) {
                        netif_err(efx, drv, efx->net_dev,
                                  "loopback %s never came up\n",
                                  LOOPBACK_MODE(efx));
                        goto out;
                }

                /* Test all enabled types of TX queue */
                efx_for_each_channel_tx_queue(tx_queue, channel) {
                        state->offload_csum = (tx_queue->queue &
                                               EFX_TXQ_TYPE_OFFLOAD);
                        rc = efx_test_loopback(tx_queue,
                                               &tests->loopback[mode]);
                        if (rc)
                                goto out;
                }
        }

 out:
        /* Remove the flush. The caller will remove the loopback setting */
        state->flush = true;
        efx->loopback_selftest = NULL;
        wmb();
        kfree(state);

        return rc;
}

/**************************************************************************
 *
 * Entry point
 *
 *************************************************************************/

int efx_selftest(struct efx_nic *efx, struct efx_self_tests *tests,
                 unsigned flags)
{
        enum efx_loopback_mode loopback_mode = efx->loopback_mode;
        int phy_mode = efx->phy_mode;
        int rc_test = 0, rc_reset, rc;

        efx_selftest_async_cancel(efx);

        /* Online (i.e. non-disruptive) testing
         * This checks interrupt generation, event delivery and PHY presence. */

        rc = efx_test_phy_alive(efx, tests);
        if (rc && !rc_test)
                rc_test = rc;

        rc = efx_test_nvram(efx, tests);
        if (rc && !rc_test)
                rc_test = rc;

        rc = efx_test_interrupts(efx, tests);
        if (rc && !rc_test)
                rc_test = rc;

        rc = efx_test_eventq_irq(efx, tests);
        if (rc && !rc_test)
                rc_test = rc;

        if (rc_test)
                return rc_test;

        if (!(flags & ETH_TEST_FL_OFFLINE))
                return efx_test_phy(efx, tests, flags);

        /* Offline (i.e. disruptive) testing
         * This checks MAC and PHY loopback on the specified port. */

        /* Detach the device so the kernel doesn't transmit during the
         * loopback test and the watchdog timeout doesn't fire.
         */
        efx_device_detach_sync(efx);

        if (efx->type->test_chip) {
                rc_reset = efx->type->test_chip(efx, tests);
                if (rc_reset) {
                        netif_err(efx, hw, efx->net_dev,
                                  "Unable to recover from chip test\n");
                        efx_schedule_reset(efx, RESET_TYPE_DISABLE);
                        return rc_reset;
                }

                if ((tests->memory < 0 || tests->registers < 0) && !rc_test)
                        rc_test = -EIO;
        }

        /* Ensure that the phy is powered and out of loopback
         * for the bist and loopback tests */
        mutex_lock(&efx->mac_lock);
        efx->phy_mode &= ~PHY_MODE_LOW_POWER;
        efx->loopback_mode = LOOPBACK_NONE;
        __efx_reconfigure_port(efx);
        mutex_unlock(&efx->mac_lock);

        rc = efx_test_phy(efx, tests, flags);
        if (rc && !rc_test)
                rc_test = rc;

        rc = efx_test_loopbacks(efx, tests, efx->loopback_modes);
        if (rc && !rc_test)
                rc_test = rc;

        /* restore the PHY to the previous state */
        mutex_lock(&efx->mac_lock);
        efx->phy_mode = phy_mode;
        efx->loopback_mode = loopback_mode;
        __efx_reconfigure_port(efx);
        mutex_unlock(&efx->mac_lock);

        netif_device_attach(efx->net_dev);

        return rc_test;
}

void efx_selftest_async_start(struct efx_nic *efx)
{
        struct efx_channel *channel;

        efx_for_each_channel(channel, efx)
                efx_nic_event_test_start(channel);
        schedule_delayed_work(&efx->selftest_work, IRQ_TIMEOUT);
}

void efx_selftest_async_cancel(struct efx_nic *efx)
{
        cancel_delayed_work_sync(&efx->selftest_work);
}

void efx_selftest_async_work(struct work_struct *data)
{
        struct efx_nic *efx = container_of(data, struct efx_nic,
                                           selftest_work.work);
        struct efx_channel *channel;
        int cpu;

        efx_for_each_channel(channel, efx) {
                cpu = efx_nic_event_test_irq_cpu(channel);
                if (cpu < 0)
                        netif_err(efx, ifup, efx->net_dev,
                                  "channel %d failed to trigger an interrupt\n",
                                  channel->channel);
                else
                        netif_dbg(efx, ifup, efx->net_dev,
                                  "channel %d triggered interrupt on CPU %d\n",
                                  channel->channel, cpu);
        }
}