/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2005-2006 Fen Systems Ltd.
 * Copyright 2005-2013 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/module.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/delay.h>
#include <linux/notifier.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/in.h>
#include <linux/ethtool.h>
#include <linux/topology.h>
#include <linux/gfp.h>
#include <linux/aer.h>
#include <linux/interrupt.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
#include "selftest.h"

#include "workarounds.h"

/**************************************************************************
 *
 * Type name strings
 *
 **************************************************************************
 */

/* Loopback mode names (see LOOPBACK_MODE()) */
const unsigned int ef4_loopback_mode_max = LOOPBACK_MAX;
const char *const ef4_loopback_mode_names[] = {
        [LOOPBACK_NONE]         = "NONE",
        [LOOPBACK_DATA]         = "DATAPATH",
        [LOOPBACK_GMAC]         = "GMAC",
        [LOOPBACK_XGMII]        = "XGMII",
        [LOOPBACK_XGXS]         = "XGXS",
        [LOOPBACK_XAUI]         = "XAUI",
        [LOOPBACK_GMII]         = "GMII",
        [LOOPBACK_SGMII]        = "SGMII",
        [LOOPBACK_XGBR]         = "XGBR",
        [LOOPBACK_XFI]          = "XFI",
        [LOOPBACK_XAUI_FAR]     = "XAUI_FAR",
        [LOOPBACK_GMII_FAR]     = "GMII_FAR",
        [LOOPBACK_SGMII_FAR]    = "SGMII_FAR",
        [LOOPBACK_XFI_FAR]      = "XFI_FAR",
        [LOOPBACK_GPHY]         = "GPHY",
        [LOOPBACK_PHYXS]        = "PHYXS",
        [LOOPBACK_PCS]          = "PCS",
        [LOOPBACK_PMAPMD]       = "PMA/PMD",
        [LOOPBACK_XPORT]        = "XPORT",
        [LOOPBACK_XGMII_WS]     = "XGMII_WS",
        [LOOPBACK_XAUI_WS]      = "XAUI_WS",
        [LOOPBACK_XAUI_WS_FAR]  = "XAUI_WS_FAR",
        [LOOPBACK_XAUI_WS_NEAR] = "XAUI_WS_NEAR",
        [LOOPBACK_GMII_WS]      = "GMII_WS",
        [LOOPBACK_XFI_WS]       = "XFI_WS",
        [LOOPBACK_XFI_WS_FAR]   = "XFI_WS_FAR",
        [LOOPBACK_PHYXS_WS]     = "PHYXS_WS",
};

const unsigned int ef4_reset_type_max = RESET_TYPE_MAX;
const char *const ef4_reset_type_names[] = {
        [RESET_TYPE_INVISIBLE]          = "INVISIBLE",
        [RESET_TYPE_ALL]                = "ALL",
        [RESET_TYPE_RECOVER_OR_ALL]     = "RECOVER_OR_ALL",
        [RESET_TYPE_WORLD]              = "WORLD",
        [RESET_TYPE_RECOVER_OR_DISABLE] = "RECOVER_OR_DISABLE",
        [RESET_TYPE_DATAPATH]           = "DATAPATH",
        [RESET_TYPE_DISABLE]            = "DISABLE",
        [RESET_TYPE_TX_WATCHDOG]        = "TX_WATCHDOG",
        [RESET_TYPE_INT_ERROR]          = "INT_ERROR",
        [RESET_TYPE_RX_RECOVERY]        = "RX_RECOVERY",
        [RESET_TYPE_DMA_ERROR]          = "DMA_ERROR",
        [RESET_TYPE_TX_SKIP]            = "TX_SKIP",
};

/* Reset workqueue. If any NIC has a hardware failure then a reset will be
 * queued onto this work queue. This is not a per-nic work queue, because
 * ef4_reset_work() acquires the rtnl lock, so resets are naturally serialised.
 */
static struct workqueue_struct *reset_workqueue;

/* How often and how many times to poll for a reset while waiting for a
 * BIST that another function started to complete.
 */
#define BIST_WAIT_DELAY_MS      100
#define BIST_WAIT_DELAY_COUNT   100

/**************************************************************************
 *
 * Configurable values
 *
 *************************************************************************/

/*
 * Use separate channels for TX and RX events
 *
 * Set this to 1 to use separate channels for TX and RX. It allows us
 * to control interrupt affinity separately for TX and RX.
 *
 * This is only used in MSI-X interrupt mode
 */
bool ef4_separate_tx_channels;
module_param(ef4_separate_tx_channels, bool, 0444);
MODULE_PARM_DESC(ef4_separate_tx_channels,
                 "Use separate channels for TX and RX");

/* This is the weight assigned to each of the (per-channel) virtual
 * NAPI devices.
 */
static int napi_weight = 64;

/* This is the time (in jiffies) between invocations of the hardware
 * monitor.
 * On Falcon-based NICs, this will:
 * - Check the on-board hardware monitor;
 * - Poll the link state and reconfigure the hardware as necessary.
 * On Siena-based NICs for power systems with EEH support, this will give EEH a
 * chance to start.
 */
static unsigned int ef4_monitor_interval = 1 * HZ;

/* Initial interrupt moderation settings.  They can be modified after
 * module load with ethtool.
 *
 * The default for RX should strike a balance between increasing the
 * round-trip latency and reducing overhead.
 */
static unsigned int rx_irq_mod_usec = 60;

/* Initial interrupt moderation settings.  They can be modified after
 * module load with ethtool.
 *
 * This default is chosen to ensure that a 10G link does not go idle
 * while a TX queue is stopped after it has become full.  A queue is
 * restarted when it drops below half full.  The time this takes (assuming
 * worst case 3 descriptors per packet and 1024 descriptors) is
 *   512 / 3 * 1.2 = 205 usec.
 */
static unsigned int tx_irq_mod_usec = 150;

/* This is the first interrupt mode to try out of:
 * 0 => MSI-X
 * 1 => MSI
 * 2 => legacy
 */
static unsigned int interrupt_mode;

/* This is the requested number of CPUs to use for Receive-Side Scaling (RSS),
 * i.e. the number of CPUs among which we may distribute simultaneous
 * interrupt handling.
 *
 * Cards without MSI-X will only target one CPU via legacy or MSI interrupt.
 * The default (0) means to assign an interrupt to each core.
 */
static unsigned int rss_cpus;
module_param(rss_cpus, uint, 0444);
MODULE_PARM_DESC(rss_cpus, "Number of CPUs to use for Receive-Side Scaling");

static bool phy_flash_cfg;
module_param(phy_flash_cfg, bool, 0644);
MODULE_PARM_DESC(phy_flash_cfg, "Set PHYs into reflash mode initially");

static unsigned irq_adapt_low_thresh = 8000;
module_param(irq_adapt_low_thresh, uint, 0644);
MODULE_PARM_DESC(irq_adapt_low_thresh,
                 "Threshold score for reducing IRQ moderation");

static unsigned irq_adapt_high_thresh = 16000;
module_param(irq_adapt_high_thresh, uint, 0644);
MODULE_PARM_DESC(irq_adapt_high_thresh,
                 "Threshold score for increasing IRQ moderation");

static unsigned debug = (NETIF_MSG_DRV | NETIF_MSG_PROBE |
                         NETIF_MSG_LINK | NETIF_MSG_IFDOWN |
                         NETIF_MSG_IFUP | NETIF_MSG_RX_ERR |
                         NETIF_MSG_TX_ERR | NETIF_MSG_HW);
module_param(debug, uint, 0);
MODULE_PARM_DESC(debug, "Bitmapped debugging message enable value");

/**************************************************************************
 *
 * Utility functions and prototypes
 *
 *************************************************************************/

static int ef4_soft_enable_interrupts(struct ef4_nic *efx);
static void ef4_soft_disable_interrupts(struct ef4_nic *efx);
static void ef4_remove_channel(struct ef4_channel *channel);
static void ef4_remove_channels(struct ef4_nic *efx);
static const struct ef4_channel_type ef4_default_channel_type;
static void ef4_remove_port(struct ef4_nic *efx);
static void ef4_init_napi_channel(struct ef4_channel *channel);
static void ef4_fini_napi(struct ef4_nic *efx);
static void ef4_fini_napi_channel(struct ef4_channel *channel);
static void ef4_fini_struct(struct ef4_nic *efx);
static void ef4_start_all(struct ef4_nic *efx);
static void ef4_stop_all(struct ef4_nic *efx);

#define EF4_ASSERT_RESET_SERIALISED(efx)                \
        do {                                            \
                if ((efx->state == STATE_READY) ||      \
                    (efx->state == STATE_RECOVERY) ||   \
                    (efx->state == STATE_DISABLED))     \
                        ASSERT_RTNL();                  \
        } while (0)

static int ef4_check_disabled(struct ef4_nic *efx)
{
        if (efx->state == STATE_DISABLED || efx->state == STATE_RECOVERY) {
                netif_err(efx, drv, efx->net_dev,
                          "device is disabled due to earlier errors\n");
                return -EIO;
        }
        return 0;
}

/**************************************************************************
 *
 * Event queue processing
 *
 *************************************************************************/

/* Process channel's event queue
 *
 * This function is responsible for processing the event queue of a
 * single channel.  The caller must guarantee that this function will
 * never be concurrently called more than once on the same channel,
 * though different channels may be being processed concurrently.
 */
static int ef4_process_channel(struct ef4_channel *channel, int budget)
{
        struct ef4_tx_queue *tx_queue;
        int spent;

        if (unlikely(!channel->enabled))
                return 0;

        ef4_for_each_channel_tx_queue(tx_queue, channel) {
                tx_queue->pkts_compl = 0;
                tx_queue->bytes_compl = 0;
        }

        spent = ef4_nic_process_eventq(channel, budget);
        if (spent && ef4_channel_has_rx_queue(channel)) {
                struct ef4_rx_queue *rx_queue =
                        ef4_channel_get_rx_queue(channel);

                ef4_rx_flush_packet(channel);
                ef4_fast_push_rx_descriptors(rx_queue, true);
        }

        /* Update BQL */
        ef4_for_each_channel_tx_queue(tx_queue, channel) {
                if (tx_queue->bytes_compl) {
                        netdev_tx_completed_queue(tx_queue->core_txq,
                                tx_queue->pkts_compl, tx_queue->bytes_compl);
                }
        }

        return spent;
}

/* NAPI poll handler
 *
 * NAPI guarantees serialisation of polls of the same device, which
 * provides the guarantee required by ef4_process_channel().
 */
static void ef4_update_irq_mod(struct ef4_nic *efx, struct ef4_channel *channel)
{
        int step = efx->irq_mod_step_us;

        if (channel->irq_mod_score < irq_adapt_low_thresh) {
                if (channel->irq_moderation_us > step) {
                        channel->irq_moderation_us -= step;
                        efx->type->push_irq_moderation(channel);
                }
        } else if (channel->irq_mod_score > irq_adapt_high_thresh) {
                if (channel->irq_moderation_us <
                    efx->irq_rx_moderation_us) {
                        channel->irq_moderation_us += step;
                        efx->type->push_irq_moderation(channel);
                }
        }

        channel->irq_count = 0;
        channel->irq_mod_score = 0;
}

static int ef4_poll(struct napi_struct *napi, int budget)
{
        struct ef4_channel *channel =
                container_of(napi, struct ef4_channel, napi_str);
        struct ef4_nic *efx = channel->efx;
        int spent;

        netif_vdbg(efx, intr, efx->net_dev,
                   "channel %d NAPI poll executing on CPU %d\n",
                   channel->channel, raw_smp_processor_id());

        spent = ef4_process_channel(channel, budget);

        if (spent < budget) {
                if (ef4_channel_has_rx_queue(channel) &&
                    efx->irq_rx_adaptive &&
                    unlikely(++channel->irq_count == 1000)) {
                        ef4_update_irq_mod(efx, channel);
                }

                ef4_filter_rfs_expire(channel);

                /* There is no race here; although napi_disable() will
                 * only wait for napi_complete(), this isn't a problem
                 * since ef4_nic_eventq_read_ack() will have no effect if
                 * interrupts have already been disabled.
                 */
                napi_complete_done(napi, spent);
                ef4_nic_eventq_read_ack(channel);
        }

        return spent;
}

/* Create event queue
 * Event queue memory allocations are done only once.  If the channel
 * is reset, the memory buffer will be reused; this guards against
 * errors during channel reset and also simplifies interrupt handling.
 */
static int ef4_probe_eventq(struct ef4_channel *channel)
{
        struct ef4_nic *efx = channel->efx;
        unsigned long entries;

        netif_dbg(efx, probe, efx->net_dev,
                  "chan %d create event queue\n", channel->channel);

        /* Build an event queue with room for one event per tx and rx buffer,
         * plus some extra for link state events and MCDI completions. */
        entries = roundup_pow_of_two(efx->rxq_entries + efx->txq_entries + 128);
        EF4_BUG_ON_PARANOID(entries > EF4_MAX_EVQ_SIZE);
        channel->eventq_mask = max(entries, EF4_MIN_EVQ_SIZE) - 1;

        return ef4_nic_probe_eventq(channel);
}

/* Prepare channel's event queue */
static int ef4_init_eventq(struct ef4_channel *channel)
{
        struct ef4_nic *efx = channel->efx;
        int rc;

        EF4_WARN_ON_PARANOID(channel->eventq_init);

        netif_dbg(efx, drv, efx->net_dev,
                  "chan %d init event queue\n", channel->channel);

        rc = ef4_nic_init_eventq(channel);
        if (rc == 0) {
                efx->type->push_irq_moderation(channel);
                channel->eventq_read_ptr = 0;
                channel->eventq_init = true;
        }
        return rc;
}

/* Enable event queue processing and NAPI */
void ef4_start_eventq(struct ef4_channel *channel)
{
        netif_dbg(channel->efx, ifup, channel->efx->net_dev,
                  "chan %d start event queue\n", channel->channel);

        /* Make sure the NAPI handler sees the enabled flag set */
        channel->enabled = true;
        smp_wmb();

        napi_enable(&channel->napi_str);
        ef4_nic_eventq_read_ack(channel);
}

/* Disable event queue processing and NAPI */
void ef4_stop_eventq(struct ef4_channel *channel)
{
        if (!channel->enabled)
                return;

        napi_disable(&channel->napi_str);
        channel->enabled = false;
}

static void ef4_fini_eventq(struct ef4_channel *channel)
{
        if (!channel->eventq_init)
                return;

        netif_dbg(channel->efx, drv, channel->efx->net_dev,
                  "chan %d fini event queue\n", channel->channel);

        ef4_nic_fini_eventq(channel);
        channel->eventq_init = false;
}

static void ef4_remove_eventq(struct ef4_channel *channel)
{
        netif_dbg(channel->efx, drv, channel->efx->net_dev,
                  "chan %d remove event queue\n", channel->channel);

        ef4_nic_remove_eventq(channel);
}

/**************************************************************************
 *
 * Channel handling
 *
 *************************************************************************/

/* Allocate and initialise a channel structure. */
static struct ef4_channel *
ef4_alloc_channel(struct ef4_nic *efx, int i, struct ef4_channel *old_channel)
{
        struct ef4_channel *channel;
        struct ef4_rx_queue *rx_queue;
        struct ef4_tx_queue *tx_queue;
        int j;

        channel = kzalloc(sizeof(*channel), GFP_KERNEL);
        if (!channel)
                return NULL;

        channel->efx = efx;
        channel->channel = i;
        channel->type = &ef4_default_channel_type;

        for (j = 0; j < EF4_TXQ_TYPES; j++) {
                tx_queue = &channel->tx_queue[j];
                tx_queue->efx = efx;
                tx_queue->queue = i * EF4_TXQ_TYPES + j;
                tx_queue->channel = channel;
        }

        rx_queue = &channel->rx_queue;
        rx_queue->efx = efx;
        setup_timer(&rx_queue->slow_fill, ef4_rx_slow_fill,
                    (unsigned long)rx_queue);

        return channel;
}

/* Allocate and initialise a channel structure, copying parameters
 * (but not resources) from an old channel structure.
 */
static struct ef4_channel *
ef4_copy_channel(const struct ef4_channel *old_channel)
{
        struct ef4_channel *channel;
        struct ef4_rx_queue *rx_queue;
        struct ef4_tx_queue *tx_queue;
        int j;

        channel = kmalloc(sizeof(*channel), GFP_KERNEL);
        if (!channel)
                return NULL;

        *channel = *old_channel;

        channel->napi_dev = NULL;
        INIT_HLIST_NODE(&channel->napi_str.napi_hash_node);
        channel->napi_str.napi_id = 0;
        channel->napi_str.state = 0;
        memset(&channel->eventq, 0, sizeof(channel->eventq));

        for (j = 0; j < EF4_TXQ_TYPES; j++) {
                tx_queue = &channel->tx_queue[j];
                if (tx_queue->channel)
                        tx_queue->channel = channel;
                tx_queue->buffer = NULL;
                memset(&tx_queue->txd, 0, sizeof(tx_queue->txd));
        }

        rx_queue = &channel->rx_queue;
        rx_queue->buffer = NULL;
        memset(&rx_queue->rxd, 0, sizeof(rx_queue->rxd));
        setup_timer(&rx_queue->slow_fill, ef4_rx_slow_fill,
                    (unsigned long)rx_queue);

        return channel;
}

static int ef4_probe_channel(struct ef4_channel *channel)
{
        struct ef4_tx_queue *tx_queue;
        struct ef4_rx_queue *rx_queue;
        int rc;

        netif_dbg(channel->efx, probe, channel->efx->net_dev,
                  "creating channel %d\n", channel->channel);

        rc = channel->type->pre_probe(channel);
        if (rc)
                goto fail;

        rc = ef4_probe_eventq(channel);
        if (rc)
                goto fail;

        ef4_for_each_channel_tx_queue(tx_queue, channel) {
                rc = ef4_probe_tx_queue(tx_queue);
                if (rc)
                        goto fail;
        }

        ef4_for_each_channel_rx_queue(rx_queue, channel) {
                rc = ef4_probe_rx_queue(rx_queue);
                if (rc)
                        goto fail;
        }

        return 0;

fail:
        ef4_remove_channel(channel);
        return rc;
}

static void
ef4_get_channel_name(struct ef4_channel *channel, char *buf, size_t len)
{
        struct ef4_nic *efx = channel->efx;
        const char *type;
        int number;

        number = channel->channel;
        if (efx->tx_channel_offset == 0) {
                type = "";
        } else if (channel->channel < efx->tx_channel_offset) {
                type = "-rx";
        } else {
                type = "-tx";
                number -= efx->tx_channel_offset;
        }
        snprintf(buf, len, "%s%s-%d", efx->name, type, number);
}

static void ef4_set_channel_names(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                channel->type->get_name(channel,
                                        efx->msi_context[channel->channel].name,
                                        sizeof(efx->msi_context[0].name));
}

static int ef4_probe_channels(struct ef4_nic *efx)
{
        struct ef4_channel *channel;
        int rc;

        /* Restart special buffer allocation */
        efx->next_buffer_table = 0;

        /* Probe channels in reverse, so that any 'extra' channels
         * use the start of the buffer table. This allows the traffic
         * channels to be resized without moving them or wasting the
         * entries before them.
         */
        ef4_for_each_channel_rev(channel, efx) {
                rc = ef4_probe_channel(channel);
                if (rc) {
                        netif_err(efx, probe, efx->net_dev,
                                  "failed to create channel %d\n",
                                  channel->channel);
                        goto fail;
                }
        }
        ef4_set_channel_names(efx);

        return 0;

fail:
        ef4_remove_channels(efx);
        return rc;
}

/* Channels are shutdown and reinitialised whilst the NIC is running
 * to propagate configuration changes (mtu, checksum offload), or
 * to clear hardware error conditions
 */
static void ef4_start_datapath(struct ef4_nic *efx)
{
        netdev_features_t old_features = efx->net_dev->features;
        bool old_rx_scatter = efx->rx_scatter;
        struct ef4_tx_queue *tx_queue;
        struct ef4_rx_queue *rx_queue;
        struct ef4_channel *channel;
        size_t rx_buf_len;

        /* Calculate the rx buffer allocation parameters required to
         * support the current MTU, including padding for header
         * alignment and overruns.
         */
        efx->rx_dma_len = (efx->rx_prefix_size +
                           EF4_MAX_FRAME_LEN(efx->net_dev->mtu) +
                           efx->type->rx_buffer_padding);
        rx_buf_len = (sizeof(struct ef4_rx_page_state) +
                      efx->rx_ip_align + efx->rx_dma_len);
        if (rx_buf_len <= PAGE_SIZE) {
                efx->rx_scatter = efx->type->always_rx_scatter;
                efx->rx_buffer_order = 0;
        } else if (efx->type->can_rx_scatter) {
                BUILD_BUG_ON(EF4_RX_USR_BUF_SIZE % L1_CACHE_BYTES);
                BUILD_BUG_ON(sizeof(struct ef4_rx_page_state) +
                             2 * ALIGN(NET_IP_ALIGN + EF4_RX_USR_BUF_SIZE,
                                       EF4_RX_BUF_ALIGNMENT) >
                             PAGE_SIZE);
                efx->rx_scatter = true;
                efx->rx_dma_len = EF4_RX_USR_BUF_SIZE;
                efx->rx_buffer_order = 0;
        } else {
                efx->rx_scatter = false;
                efx->rx_buffer_order = get_order(rx_buf_len);
        }

        ef4_rx_config_page_split(efx);
        if (efx->rx_buffer_order)
                netif_dbg(efx, drv, efx->net_dev,
                          "RX buf len=%u; page order=%u batch=%u\n",
                          efx->rx_dma_len, efx->rx_buffer_order,
                          efx->rx_pages_per_batch);
        else
                netif_dbg(efx, drv, efx->net_dev,
                          "RX buf len=%u step=%u bpp=%u; page batch=%u\n",
                          efx->rx_dma_len, efx->rx_page_buf_step,
                          efx->rx_bufs_per_page, efx->rx_pages_per_batch);

        /* Restore previously fixed features in hw_features and remove
         * features which are fixed now
         */
        efx->net_dev->hw_features |= efx->net_dev->features;
        efx->net_dev->hw_features &= ~efx->fixed_features;
        efx->net_dev->features |= efx->fixed_features;
        if (efx->net_dev->features != old_features)
                netdev_features_change(efx->net_dev);

        /* RX filters may also have scatter-enabled flags */
        if (efx->rx_scatter != old_rx_scatter)
                efx->type->filter_update_rx_scatter(efx);

        /* We must keep at least one descriptor in a TX ring empty.
         * We could avoid this when the queue size does not exactly
         * match the hardware ring size, but it's not that important.
         * Therefore we stop the queue when one more skb might fill
         * the ring completely.  We wake it when half way back to
         * empty.
         */
        efx->txq_stop_thresh = efx->txq_entries - ef4_tx_max_skb_descs(efx);
        efx->txq_wake_thresh = efx->txq_stop_thresh / 2;

        /* Initialise the channels */
        ef4_for_each_channel(channel, efx) {
                ef4_for_each_channel_tx_queue(tx_queue, channel) {
                        ef4_init_tx_queue(tx_queue);
                        atomic_inc(&efx->active_queues);
                }

                ef4_for_each_channel_rx_queue(rx_queue, channel) {
                        ef4_init_rx_queue(rx_queue);
                        atomic_inc(&efx->active_queues);
                        ef4_stop_eventq(channel);
                        ef4_fast_push_rx_descriptors(rx_queue, false);
                        ef4_start_eventq(channel);
                }

                WARN_ON(channel->rx_pkt_n_frags);
        }

        if (netif_device_present(efx->net_dev))
                netif_tx_wake_all_queues(efx->net_dev);
}

static void ef4_stop_datapath(struct ef4_nic *efx)
{
        struct ef4_channel *channel;
        struct ef4_tx_queue *tx_queue;
        struct ef4_rx_queue *rx_queue;
        int rc;

        EF4_ASSERT_RESET_SERIALISED(efx);
        BUG_ON(efx->port_enabled);

        /* Stop RX refill */
        ef4_for_each_channel(channel, efx) {
                ef4_for_each_channel_rx_queue(rx_queue, channel)
                        rx_queue->refill_enabled = false;
        }

        ef4_for_each_channel(channel, efx) {
                /* RX packet processing is pipelined, so wait for the
                 * NAPI handler to complete.  At least event queue 0
                 * might be kept active by non-data events, so don't
                 * use napi_synchronize() but actually disable NAPI
                 * temporarily.
                 */
                if (ef4_channel_has_rx_queue(channel)) {
                        ef4_stop_eventq(channel);
                        ef4_start_eventq(channel);
                }
        }

        rc = efx->type->fini_dmaq(efx);
        if (rc && EF4_WORKAROUND_7803(efx)) {
                /* Schedule a reset to recover from the flush failure. The
                 * descriptor caches reference memory we're about to free,
                 * but falcon_reconfigure_mac_wrapper() won't reconnect
                 * the MACs because of the pending reset.
                 */
                netif_err(efx, drv, efx->net_dev,
                          "Resetting to recover from flush failure\n");
                ef4_schedule_reset(efx, RESET_TYPE_ALL);
        } else if (rc) {
                netif_err(efx, drv, efx->net_dev, "failed to flush queues\n");
        } else {
                netif_dbg(efx, drv, efx->net_dev,
                          "successfully flushed all queues\n");
        }

        ef4_for_each_channel(channel, efx) {
                ef4_for_each_channel_rx_queue(rx_queue, channel)
                        ef4_fini_rx_queue(rx_queue);
                ef4_for_each_possible_channel_tx_queue(tx_queue, channel)
                        ef4_fini_tx_queue(tx_queue);
        }
}

static void ef4_remove_channel(struct ef4_channel *channel)
{
        struct ef4_tx_queue *tx_queue;
        struct ef4_rx_queue *rx_queue;

        netif_dbg(channel->efx, drv, channel->efx->net_dev,
                  "destroy chan %d\n", channel->channel);

        ef4_for_each_channel_rx_queue(rx_queue, channel)
                ef4_remove_rx_queue(rx_queue);
        ef4_for_each_possible_channel_tx_queue(tx_queue, channel)
                ef4_remove_tx_queue(tx_queue);
        ef4_remove_eventq(channel);
        channel->type->post_remove(channel);
}

static void ef4_remove_channels(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                ef4_remove_channel(channel);
}

int
ef4_realloc_channels(struct ef4_nic *efx, u32 rxq_entries, u32 txq_entries)
{
        struct ef4_channel *other_channel[EF4_MAX_CHANNELS], *channel;
        u32 old_rxq_entries, old_txq_entries;
        unsigned i, next_buffer_table = 0;
        int rc, rc2;

        rc = ef4_check_disabled(efx);
        if (rc)
                return rc;

        /* Not all channels should be reallocated. We must avoid
         * reallocating their buffer table entries.
         */
        ef4_for_each_channel(channel, efx) {
                struct ef4_rx_queue *rx_queue;
                struct ef4_tx_queue *tx_queue;

                if (channel->type->copy)
                        continue;
                next_buffer_table = max(next_buffer_table,
                                        channel->eventq.index +
                                        channel->eventq.entries);
                ef4_for_each_channel_rx_queue(rx_queue, channel)
                        next_buffer_table = max(next_buffer_table,
                                                rx_queue->rxd.index +
                                                rx_queue->rxd.entries);
                ef4_for_each_channel_tx_queue(tx_queue, channel)
                        next_buffer_table = max(next_buffer_table,
                                                tx_queue->txd.index +
                                                tx_queue->txd.entries);
        }

        ef4_device_detach_sync(efx);
        ef4_stop_all(efx);
        ef4_soft_disable_interrupts(efx);

        /* Clone channels (where possible) */
        memset(other_channel, 0, sizeof(other_channel));
        for (i = 0; i < efx->n_channels; i++) {
                channel = efx->channel[i];
                if (channel->type->copy)
                        channel = channel->type->copy(channel);
                if (!channel) {
                        rc = -ENOMEM;
                        goto out;
                }
                other_channel[i] = channel;
        }

        /* Swap entry counts and channel pointers */
        old_rxq_entries = efx->rxq_entries;
        old_txq_entries = efx->txq_entries;
        efx->rxq_entries = rxq_entries;
        efx->txq_entries = txq_entries;
        for (i = 0; i < efx->n_channels; i++) {
                channel = efx->channel[i];
                efx->channel[i] = other_channel[i];
                other_channel[i] = channel;
        }

        /* Restart buffer table allocation */
        efx->next_buffer_table = next_buffer_table;

        for (i = 0; i < efx->n_channels; i++) {
                channel = efx->channel[i];
                if (!channel->type->copy)
                        continue;
                rc = ef4_probe_channel(channel);
                if (rc)
                        goto rollback;
                ef4_init_napi_channel(efx->channel[i]);
        }

out:
        /* Destroy unused channel structures */
        for (i = 0; i < efx->n_channels; i++) {
                channel = other_channel[i];
                if (channel && channel->type->copy) {
                        ef4_fini_napi_channel(channel);
                        ef4_remove_channel(channel);
                        kfree(channel);
                }
        }

        rc2 = ef4_soft_enable_interrupts(efx);
        if (rc2) {
                rc = rc ? rc : rc2;
                netif_err(efx, drv, efx->net_dev,
                          "unable to restart interrupts on channel reallocation\n");
                ef4_schedule_reset(efx, RESET_TYPE_DISABLE);
        } else {
                ef4_start_all(efx);
                netif_device_attach(efx->net_dev);
        }
        return rc;

rollback:
        /* Swap back */
        efx->rxq_entries = old_rxq_entries;
        efx->txq_entries = old_txq_entries;
        for (i = 0; i < efx->n_channels; i++) {
                channel = efx->channel[i];
                efx->channel[i] = other_channel[i];
                other_channel[i] = channel;
        }
        goto out;
}

void ef4_schedule_slow_fill(struct ef4_rx_queue *rx_queue)
{
        mod_timer(&rx_queue->slow_fill, jiffies + msecs_to_jiffies(100));
}

static const struct ef4_channel_type ef4_default_channel_type = {
        .pre_probe              = ef4_channel_dummy_op_int,
        .post_remove            = ef4_channel_dummy_op_void,
        .get_name               = ef4_get_channel_name,
        .copy                   = ef4_copy_channel,
        .keep_eventq            = false,
};

int ef4_channel_dummy_op_int(struct ef4_channel *channel)
{
        return 0;
}

void ef4_channel_dummy_op_void(struct ef4_channel *channel)
{
}

/**************************************************************************
 *
 * Port handling
 *
 **************************************************************************/

/* This ensures that the kernel is kept informed (via
 * netif_carrier_on/off) of the link status, and also maintains the
 * link status's stop on the port's TX queue.
 */
void ef4_link_status_changed(struct ef4_nic *efx)
{
        struct ef4_link_state *link_state = &efx->link_state;

        /* SFC Bug 5356: A net_dev notifier is registered, so we must ensure
         * that no events are triggered between unregister_netdev() and the
         * driver unloading. A more general condition is that NETDEV_CHANGE
         * can only be generated between NETDEV_UP and NETDEV_DOWN */
        if (!netif_running(efx->net_dev))
                return;

        if (link_state->up != netif_carrier_ok(efx->net_dev)) {
                efx->n_link_state_changes++;

                if (link_state->up)
                        netif_carrier_on(efx->net_dev);
                else
                        netif_carrier_off(efx->net_dev);
        }

        /* Status message for kernel log */
        if (link_state->up)
                netif_info(efx, link, efx->net_dev,
                           "link up at %uMbps %s-duplex (MTU %d)\n",
                           link_state->speed, link_state->fd ? "full" : "half",
                           efx->net_dev->mtu);
        else
                netif_info(efx, link, efx->net_dev, "link down\n");
}

void ef4_link_set_advertising(struct ef4_nic *efx, u32 advertising)
{
        efx->link_advertising = advertising;
        if (advertising) {
                if (advertising & ADVERTISED_Pause)
                        efx->wanted_fc |= (EF4_FC_TX | EF4_FC_RX);
                else
                        efx->wanted_fc &= ~(EF4_FC_TX | EF4_FC_RX);
                if (advertising & ADVERTISED_Asym_Pause)
                        efx->wanted_fc ^= EF4_FC_TX;
        }
}

void ef4_link_set_wanted_fc(struct ef4_nic *efx, u8 wanted_fc)
{
        efx->wanted_fc = wanted_fc;
        if (efx->link_advertising) {
                if (wanted_fc & EF4_FC_RX)
                        efx->link_advertising |= (ADVERTISED_Pause |
                                                  ADVERTISED_Asym_Pause);
                else
                        efx->link_advertising &= ~(ADVERTISED_Pause |
                                                   ADVERTISED_Asym_Pause);
                if (wanted_fc & EF4_FC_TX)
                        efx->link_advertising ^= ADVERTISED_Asym_Pause;
        }
}

static void ef4_fini_port(struct ef4_nic *efx);

/* We assume that efx->type->reconfigure_mac will always try to sync RX
 * filters and therefore needs to read-lock the filter table against freeing
 */
void ef4_mac_reconfigure(struct ef4_nic *efx)
{
        down_read(&efx->filter_sem);
        efx->type->reconfigure_mac(efx);
        up_read(&efx->filter_sem);
}

/* Push loopback/power/transmit disable settings to the PHY, and reconfigure
 * the MAC appropriately. All other PHY configuration changes are pushed
 * through phy_op->set_link_ksettings(), and pushed asynchronously to the MAC
 * through ef4_monitor().
 *
 * Callers must hold the mac_lock
 */
int __ef4_reconfigure_port(struct ef4_nic *efx)
{
        enum ef4_phy_mode phy_mode;
        int rc;

        WARN_ON(!mutex_is_locked(&efx->mac_lock));

        /* Disable PHY transmit in mac level loopbacks */
        phy_mode = efx->phy_mode;
        if (LOOPBACK_INTERNAL(efx))
                efx->phy_mode |= PHY_MODE_TX_DISABLED;
        else
                efx->phy_mode &= ~PHY_MODE_TX_DISABLED;

        rc = efx->type->reconfigure_port(efx);

        if (rc)
                efx->phy_mode = phy_mode;

        return rc;
}

/* Reinitialise the MAC to pick up new PHY settings, even if the port is
 * disabled. */
int ef4_reconfigure_port(struct ef4_nic *efx)
{
        int rc;

        EF4_ASSERT_RESET_SERIALISED(efx);

        mutex_lock(&efx->mac_lock);
        rc = __ef4_reconfigure_port(efx);
        mutex_unlock(&efx->mac_lock);

        return rc;
}

/* Asynchronous work item for changing MAC promiscuity and multicast
 * hash.  Avoid a drain/rx_ingress enable by reconfiguring the current
 * MAC directly. */
static void ef4_mac_work(struct work_struct *data)
{
        struct ef4_nic *efx = container_of(data, struct ef4_nic, mac_work);

        mutex_lock(&efx->mac_lock);
        if (efx->port_enabled)
                ef4_mac_reconfigure(efx);
        mutex_unlock(&efx->mac_lock);
}

static int ef4_probe_port(struct ef4_nic *efx)
{
        int rc;

        netif_dbg(efx, probe, efx->net_dev, "create port\n");

        if (phy_flash_cfg)
                efx->phy_mode = PHY_MODE_SPECIAL;

        /* Connect up MAC/PHY operations table */
        rc = efx->type->probe_port(efx);
        if (rc)
                return rc;

        /* Initialise MAC address to permanent address */
        ether_addr_copy(efx->net_dev->dev_addr, efx->net_dev->perm_addr);

        return 0;
}

static int ef4_init_port(struct ef4_nic *efx)
{
        int rc;

        netif_dbg(efx, drv, efx->net_dev, "init port\n");

        mutex_lock(&efx->mac_lock);

        rc = efx->phy_op->init(efx);
        if (rc)
                goto fail1;

        efx->port_initialized = true;

        /* Reconfigure the MAC before creating dma queues (required for
         * Falcon/A1 where RX_INGR_EN/TX_DRAIN_EN isn't supported) */
        ef4_mac_reconfigure(efx);

        /* Ensure the PHY advertises the correct flow control settings */
        rc = efx->phy_op->reconfigure(efx);
        if (rc && rc != -EPERM)
                goto fail2;

        mutex_unlock(&efx->mac_lock);
        return 0;

fail2:
        efx->phy_op->fini(efx);
fail1:
        mutex_unlock(&efx->mac_lock);
        return rc;
}

static void ef4_start_port(struct ef4_nic *efx)
{
        netif_dbg(efx, ifup, efx->net_dev, "start port\n");
        BUG_ON(efx->port_enabled);

        mutex_lock(&efx->mac_lock);
        efx->port_enabled = true;

        /* Ensure MAC ingress/egress is enabled */
        ef4_mac_reconfigure(efx);

        mutex_unlock(&efx->mac_lock);
}

/* Cancel work for MAC reconfiguration, periodic hardware monitoring
 * and the async self-test, wait for them to finish and prevent them
 * being scheduled again.  This doesn't cover online resets, which
 * should only be cancelled when removing the device.
 */
static void ef4_stop_port(struct ef4_nic *efx)
{
        netif_dbg(efx, ifdown, efx->net_dev, "stop port\n");

        EF4_ASSERT_RESET_SERIALISED(efx);

        mutex_lock(&efx->mac_lock);
        efx->port_enabled = false;
        mutex_unlock(&efx->mac_lock);

        /* Serialise against ef4_set_multicast_list() */
        netif_addr_lock_bh(efx->net_dev);
        netif_addr_unlock_bh(efx->net_dev);

        cancel_delayed_work_sync(&efx->monitor_work);
        ef4_selftest_async_cancel(efx);
        cancel_work_sync(&efx->mac_work);
}

static void ef4_fini_port(struct ef4_nic *efx)
{
        netif_dbg(efx, drv, efx->net_dev, "shut down port\n");

        if (!efx->port_initialized)
                return;

        efx->phy_op->fini(efx);
        efx->port_initialized = false;

        efx->link_state.up = false;
        ef4_link_status_changed(efx);
}

static void ef4_remove_port(struct ef4_nic *efx)
{
        netif_dbg(efx, drv, efx->net_dev, "destroying port\n");

        efx->type->remove_port(efx);
}

/**************************************************************************
 *
 * NIC handling
 *
 **************************************************************************/

static LIST_HEAD(ef4_primary_list);
static LIST_HEAD(ef4_unassociated_list);

static bool ef4_same_controller(struct ef4_nic *left, struct ef4_nic *right)
{
        return left->type == right->type &&
                left->vpd_sn && right->vpd_sn &&
                !strcmp(left->vpd_sn, right->vpd_sn);
}

static void ef4_associate(struct ef4_nic *efx)
{
        struct ef4_nic *other, *next;

        if (efx->primary == efx) {
                /* Adding primary function; look for secondaries */

                netif_dbg(efx, probe, efx->net_dev, "adding to primary list\n");
                list_add_tail(&efx->node, &ef4_primary_list);

                list_for_each_entry_safe(other, next, &ef4_unassociated_list,
                                         node) {
                        if (ef4_same_controller(efx, other)) {
                                list_del(&other->node);
                                netif_dbg(other, probe, other->net_dev,
                                          "moving to secondary list of %s %s\n",
                                          pci_name(efx->pci_dev),
                                          efx->net_dev->name);
                                list_add_tail(&other->node,
                                              &efx->secondary_list);
                                other->primary = efx;
                        }
                }
        } else {
                /* Adding secondary function; look for primary */

                list_for_each_entry(other, &ef4_primary_list, node) {
                        if (ef4_same_controller(efx, other)) {
                                netif_dbg(efx, probe, efx->net_dev,
                                          "adding to secondary list of %s %s\n",
                                          pci_name(other->pci_dev),
                                          other->net_dev->name);
                                list_add_tail(&efx->node,
                                              &other->secondary_list);
                                efx->primary = other;
                                return;
                        }
                }

                netif_dbg(efx, probe, efx->net_dev,
                          "adding to unassociated list\n");
                list_add_tail(&efx->node, &ef4_unassociated_list);
        }
}

static void ef4_dissociate(struct ef4_nic *efx)
{
        struct ef4_nic *other, *next;

        list_del(&efx->node);
        efx->primary = NULL;

        list_for_each_entry_safe(other, next, &efx->secondary_list, node) {
                list_del(&other->node);
                netif_dbg(other, probe, other->net_dev,
                          "moving to unassociated list\n");
                list_add_tail(&other->node, &ef4_unassociated_list);
                other->primary = NULL;
        }
}

/* This configures the PCI device to enable I/O and DMA. */
static int ef4_init_io(struct ef4_nic *efx)
{
        struct pci_dev *pci_dev = efx->pci_dev;
        dma_addr_t dma_mask = efx->type->max_dma_mask;
        unsigned int mem_map_size = efx->type->mem_map_size(efx);
        int rc, bar;

        netif_dbg(efx, probe, efx->net_dev, "initialising I/O\n");

        bar = efx->type->mem_bar;

        rc = pci_enable_device(pci_dev);
        if (rc) {
                netif_err(efx, probe, efx->net_dev,
                          "failed to enable PCI device\n");
                goto fail1;
        }

        pci_set_master(pci_dev);

        /* Set the PCI DMA mask.  Try all possibilities from our
         * genuine mask down to 32 bits, because some architectures
         * (e.g. x86_64 with iommu_sac_force set) will allow 40 bit
         * masks event though they reject 46 bit masks.
         */
        while (dma_mask > 0x7fffffffUL) {
                rc = dma_set_mask_and_coherent(&pci_dev->dev, dma_mask);
                if (rc == 0)
                        break;
                dma_mask >>= 1;
        }
        if (rc) {
                netif_err(efx, probe, efx->net_dev,
                          "could not find a suitable DMA mask\n");
                goto fail2;
        }
        netif_dbg(efx, probe, efx->net_dev,
                  "using DMA mask %llx\n", (unsigned long long) dma_mask);

        efx->membase_phys = pci_resource_start(efx->pci_dev, bar);
        rc = pci_request_region(pci_dev, bar, "sfc");
        if (rc) {
                netif_err(efx, probe, efx->net_dev,
                          "request for memory BAR failed\n");
                rc = -EIO;
                goto fail3;
        }
        efx->membase = ioremap_nocache(efx->membase_phys, mem_map_size);
        if (!efx->membase) {
                netif_err(efx, probe, efx->net_dev,
                          "could not map memory BAR at %llx+%x\n",
                          (unsigned long long)efx->membase_phys, mem_map_size);
                rc = -ENOMEM;
                goto fail4;
        }
        netif_dbg(efx, probe, efx->net_dev,
                  "memory BAR at %llx+%x (virtual %p)\n",
                  (unsigned long long)efx->membase_phys, mem_map_size,
                  efx->membase);

        return 0;

 fail4:
        pci_release_region(efx->pci_dev, bar);
 fail3:
        efx->membase_phys = 0;
 fail2:
        pci_disable_device(efx->pci_dev);
 fail1:
        return rc;
}

static void ef4_fini_io(struct ef4_nic *efx)
{
        int bar;

        netif_dbg(efx, drv, efx->net_dev, "shutting down I/O\n");

        if (efx->membase) {
                iounmap(efx->membase);
                efx->membase = NULL;
        }

        if (efx->membase_phys) {
                bar = efx->type->mem_bar;
                pci_release_region(efx->pci_dev, bar);
                efx->membase_phys = 0;
        }

        /* Don't disable bus-mastering if VFs are assigned */
        if (!pci_vfs_assigned(efx->pci_dev))
                pci_disable_device(efx->pci_dev);
}

void ef4_set_default_rx_indir_table(struct ef4_nic *efx)
{
        size_t i;

        for (i = 0; i < ARRAY_SIZE(efx->rx_indir_table); i++)
                efx->rx_indir_table[i] =
                        ethtool_rxfh_indir_default(i, efx->rss_spread);
}

static unsigned int ef4_wanted_parallelism(struct ef4_nic *efx)
{
        cpumask_var_t thread_mask;
        unsigned int count;
        int cpu;

        if (rss_cpus) {
                count = rss_cpus;
        } else {
                if (unlikely(!zalloc_cpumask_var(&thread_mask, GFP_KERNEL))) {
                        netif_warn(efx, probe, efx->net_dev,
                                   "RSS disabled due to allocation failure\n");
                        return 1;
                }

                count = 0;
                for_each_online_cpu(cpu) {
                        if (!cpumask_test_cpu(cpu, thread_mask)) {
                                ++count;
                                cpumask_or(thread_mask, thread_mask,
                                           topology_sibling_cpumask(cpu));
                        }
                }

                free_cpumask_var(thread_mask);
        }

        if (count > EF4_MAX_RX_QUEUES) {
                netif_cond_dbg(efx, probe, efx->net_dev, !rss_cpus, warn,
                               "Reducing number of rx queues from %u to %u.\n",
                               count, EF4_MAX_RX_QUEUES);
                count = EF4_MAX_RX_QUEUES;
        }

        return count;
}

/* Probe the number and type of interrupts we are able to obtain, and
 * the resulting numbers of channels and RX queues.
 */
static int ef4_probe_interrupts(struct ef4_nic *efx)
{
        unsigned int extra_channels = 0;
        unsigned int i, j;
        int rc;

        for (i = 0; i < EF4_MAX_EXTRA_CHANNELS; i++)
                if (efx->extra_channel_type[i])
                        ++extra_channels;

        if (efx->interrupt_mode == EF4_INT_MODE_MSIX) {
                struct msix_entry xentries[EF4_MAX_CHANNELS];
                unsigned int n_channels;

                n_channels = ef4_wanted_parallelism(efx);
                if (ef4_separate_tx_channels)
                        n_channels *= 2;
                n_channels += extra_channels;
                n_channels = min(n_channels, efx->max_channels);

                for (i = 0; i < n_channels; i++)
                        xentries[i].entry = i;
                rc = pci_enable_msix_range(efx->pci_dev,
                                           xentries, 1, n_channels);
                if (rc < 0) {
                        /* Fall back to single channel MSI */
                        efx->interrupt_mode = EF4_INT_MODE_MSI;
                        netif_err(efx, drv, efx->net_dev,
                                  "could not enable MSI-X\n");
                } else if (rc < n_channels) {
                        netif_err(efx, drv, efx->net_dev,
                                  "WARNING: Insufficient MSI-X vectors"
                                  " available (%d < %u).\n", rc, n_channels);
                        netif_err(efx, drv, efx->net_dev,
                                  "WARNING: Performance may be reduced.\n");
                        n_channels = rc;
                }

                if (rc > 0) {
                        efx->n_channels = n_channels;
                        if (n_channels > extra_channels)
                                n_channels -= extra_channels;
                        if (ef4_separate_tx_channels) {
                                efx->n_tx_channels = min(max(n_channels / 2,
                                                             1U),
                                                         efx->max_tx_channels);
                                efx->n_rx_channels = max(n_channels -
                                                         efx->n_tx_channels,
                                                         1U);
                        } else {
                                efx->n_tx_channels = min(n_channels,
                                                         efx->max_tx_channels);
                                efx->n_rx_channels = n_channels;
                        }
                        for (i = 0; i < efx->n_channels; i++)
                                ef4_get_channel(efx, i)->irq =
                                        xentries[i].vector;
                }
        }

        /* Try single interrupt MSI */
        if (efx->interrupt_mode == EF4_INT_MODE_MSI) {
                efx->n_channels = 1;
                efx->n_rx_channels = 1;
                efx->n_tx_channels = 1;
                rc = pci_enable_msi(efx->pci_dev);
                if (rc == 0) {
                        ef4_get_channel(efx, 0)->irq = efx->pci_dev->irq;
                } else {
                        netif_err(efx, drv, efx->net_dev,
                                  "could not enable MSI\n");
                        efx->interrupt_mode = EF4_INT_MODE_LEGACY;
                }
        }

        /* Assume legacy interrupts */
        if (efx->interrupt_mode == EF4_INT_MODE_LEGACY) {
                efx->n_channels = 1 + (ef4_separate_tx_channels ? 1 : 0);
                efx->n_rx_channels = 1;
                efx->n_tx_channels = 1;
                efx->legacy_irq = efx->pci_dev->irq;
        }

        /* Assign extra channels if possible */
        j = efx->n_channels;
        for (i = 0; i < EF4_MAX_EXTRA_CHANNELS; i++) {
                if (!efx->extra_channel_type[i])
                        continue;
                if (efx->interrupt_mode != EF4_INT_MODE_MSIX ||
                    efx->n_channels <= extra_channels) {
                        efx->extra_channel_type[i]->handle_no_channel(efx);
                } else {
                        --j;
                        ef4_get_channel(efx, j)->type =
                                efx->extra_channel_type[i];
                }
        }

        efx->rss_spread = efx->n_rx_channels;

        return 0;
}

static int ef4_soft_enable_interrupts(struct ef4_nic *efx)
{
        struct ef4_channel *channel, *end_channel;
        int rc;

        BUG_ON(efx->state == STATE_DISABLED);

        efx->irq_soft_enabled = true;
        smp_wmb();

        ef4_for_each_channel(channel, efx) {
                if (!channel->type->keep_eventq) {
                        rc = ef4_init_eventq(channel);
                        if (rc)
                                goto fail;
                }
                ef4_start_eventq(channel);
        }

        return 0;
fail:
        end_channel = channel;
        ef4_for_each_channel(channel, efx) {
                if (channel == end_channel)
                        break;
                ef4_stop_eventq(channel);
                if (!channel->type->keep_eventq)
                        ef4_fini_eventq(channel);
        }

        return rc;
}

static void ef4_soft_disable_interrupts(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        if (efx->state == STATE_DISABLED)
                return;

        efx->irq_soft_enabled = false;
        smp_wmb();

        if (efx->legacy_irq)
                synchronize_irq(efx->legacy_irq);

        ef4_for_each_channel(channel, efx) {
                if (channel->irq)
                        synchronize_irq(channel->irq);

                ef4_stop_eventq(channel);
                if (!channel->type->keep_eventq)
                        ef4_fini_eventq(channel);
        }
}

static int ef4_enable_interrupts(struct ef4_nic *efx)
{
        struct ef4_channel *channel, *end_channel;
        int rc;

        BUG_ON(efx->state == STATE_DISABLED);

        if (efx->eeh_disabled_legacy_irq) {
                enable_irq(efx->legacy_irq);
                efx->eeh_disabled_legacy_irq = false;
        }

        efx->type->irq_enable_master(efx);

        ef4_for_each_channel(channel, efx) {
                if (channel->type->keep_eventq) {
                        rc = ef4_init_eventq(channel);
                        if (rc)
                                goto fail;
                }
        }

        rc = ef4_soft_enable_interrupts(efx);
        if (rc)
                goto fail;

        return 0;

fail:
        end_channel = channel;
        ef4_for_each_channel(channel, efx) {
                if (channel == end_channel)
                        break;
                if (channel->type->keep_eventq)
                        ef4_fini_eventq(channel);
        }

        efx->type->irq_disable_non_ev(efx);

        return rc;
}

static void ef4_disable_interrupts(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        ef4_soft_disable_interrupts(efx);

        ef4_for_each_channel(channel, efx) {
                if (channel->type->keep_eventq)
                        ef4_fini_eventq(channel);
        }

        efx->type->irq_disable_non_ev(efx);
}

static void ef4_remove_interrupts(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        /* Remove MSI/MSI-X interrupts */
        ef4_for_each_channel(channel, efx)
                channel->irq = 0;
        pci_disable_msi(efx->pci_dev);
        pci_disable_msix(efx->pci_dev);

        /* Remove legacy interrupt */
        efx->legacy_irq = 0;
}

static void ef4_set_channels(struct ef4_nic *efx)
{
        struct ef4_channel *channel;
        struct ef4_tx_queue *tx_queue;

        efx->tx_channel_offset =
                ef4_separate_tx_channels ?
                efx->n_channels - efx->n_tx_channels : 0;

        /* We need to mark which channels really have RX and TX
         * queues, and adjust the TX queue numbers if we have separate
         * RX-only and TX-only channels.
         */
        ef4_for_each_channel(channel, efx) {
                if (channel->channel < efx->n_rx_channels)
                        channel->rx_queue.core_index = channel->channel;
                else
                        channel->rx_queue.core_index = -1;

                ef4_for_each_channel_tx_queue(tx_queue, channel)
                        tx_queue->queue -= (efx->tx_channel_offset *
                                            EF4_TXQ_TYPES);
        }
}

static int ef4_probe_nic(struct ef4_nic *efx)
{
        int rc;

        netif_dbg(efx, probe, efx->net_dev, "creating NIC\n");

        /* Carry out hardware-type specific initialisation */
        rc = efx->type->probe(efx);
        if (rc)
                return rc;

        do {
                if (!efx->max_channels || !efx->max_tx_channels) {
                        netif_err(efx, drv, efx->net_dev,
                                  "Insufficient resources to allocate"
                                  " any channels\n");
                        rc = -ENOSPC;
                        goto fail1;
                }

                /* Determine the number of channels and queues by trying
                 * to hook in MSI-X interrupts.
                 */
                rc = ef4_probe_interrupts(efx);
                if (rc)
                        goto fail1;

                ef4_set_channels(efx);

                /* dimension_resources can fail with EAGAIN */
                rc = efx->type->dimension_resources(efx);
                if (rc != 0 && rc != -EAGAIN)
                        goto fail2;

                if (rc == -EAGAIN)
                        /* try again with new max_channels */
                        ef4_remove_interrupts(efx);

        } while (rc == -EAGAIN);

        if (efx->n_channels > 1)
                netdev_rss_key_fill(&efx->rx_hash_key,
                                    sizeof(efx->rx_hash_key));
        ef4_set_default_rx_indir_table(efx);

        netif_set_real_num_tx_queues(efx->net_dev, efx->n_tx_channels);
        netif_set_real_num_rx_queues(efx->net_dev, efx->n_rx_channels);

        /* Initialise the interrupt moderation settings */
        efx->irq_mod_step_us = DIV_ROUND_UP(efx->timer_quantum_ns, 1000);
        ef4_init_irq_moderation(efx, tx_irq_mod_usec, rx_irq_mod_usec, true,
                                true);

        return 0;

fail2:
        ef4_remove_interrupts(efx);
fail1:
        efx->type->remove(efx);
        return rc;
}

static void ef4_remove_nic(struct ef4_nic *efx)
{
        netif_dbg(efx, drv, efx->net_dev, "destroying NIC\n");

        ef4_remove_interrupts(efx);
        efx->type->remove(efx);
}

static int ef4_probe_filters(struct ef4_nic *efx)
{
        int rc;

        spin_lock_init(&efx->filter_lock);
        init_rwsem(&efx->filter_sem);
        mutex_lock(&efx->mac_lock);
        down_write(&efx->filter_sem);
        rc = efx->type->filter_table_probe(efx);
        if (rc)
                goto out_unlock;

#ifdef CONFIG_RFS_ACCEL
        if (efx->type->offload_features & NETIF_F_NTUPLE) {
                struct ef4_channel *channel;
                int i, success = 1;

                ef4_for_each_channel(channel, efx) {
                        channel->rps_flow_id =
                                kcalloc(efx->type->max_rx_ip_filters,
                                        sizeof(*channel->rps_flow_id),
                                        GFP_KERNEL);
                        if (!channel->rps_flow_id)
                                success = 0;
                        else
                                for (i = 0;
                                     i < efx->type->max_rx_ip_filters;
                                     ++i)
                                        channel->rps_flow_id[i] =
                                                RPS_FLOW_ID_INVALID;
                }

                if (!success) {
                        ef4_for_each_channel(channel, efx)
                                kfree(channel->rps_flow_id);
                        efx->type->filter_table_remove(efx);
                        rc = -ENOMEM;
                        goto out_unlock;
                }

                efx->rps_expire_index = efx->rps_expire_channel = 0;
        }
#endif
out_unlock:
        up_write(&efx->filter_sem);
        mutex_unlock(&efx->mac_lock);
        return rc;
}

static void ef4_remove_filters(struct ef4_nic *efx)
{
#ifdef CONFIG_RFS_ACCEL
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                kfree(channel->rps_flow_id);
#endif
        down_write(&efx->filter_sem);
        efx->type->filter_table_remove(efx);
        up_write(&efx->filter_sem);
}

static void ef4_restore_filters(struct ef4_nic *efx)
{
        down_read(&efx->filter_sem);
        efx->type->filter_table_restore(efx);
        up_read(&efx->filter_sem);
}

/**************************************************************************
 *
 * NIC startup/shutdown
 *
 *************************************************************************/

static int ef4_probe_all(struct ef4_nic *efx)
{
        int rc;

        rc = ef4_probe_nic(efx);
        if (rc) {
                netif_err(efx, probe, efx->net_dev, "failed to create NIC\n");
                goto fail1;
        }

        rc = ef4_probe_port(efx);
        if (rc) {
                netif_err(efx, probe, efx->net_dev, "failed to create port\n");
                goto fail2;
        }

        BUILD_BUG_ON(EF4_DEFAULT_DMAQ_SIZE < EF4_RXQ_MIN_ENT);
        if (WARN_ON(EF4_DEFAULT_DMAQ_SIZE < EF4_TXQ_MIN_ENT(efx))) {
                rc = -EINVAL;
                goto fail3;
        }
        efx->rxq_entries = efx->txq_entries = EF4_DEFAULT_DMAQ_SIZE;

        rc = ef4_probe_filters(efx);
        if (rc) {
                netif_err(efx, probe, efx->net_dev,
                          "failed to create filter tables\n");
                goto fail4;
        }

        rc = ef4_probe_channels(efx);
        if (rc)
                goto fail5;

        return 0;

 fail5:
        ef4_remove_filters(efx);
 fail4:
 fail3:
        ef4_remove_port(efx);
 fail2:
        ef4_remove_nic(efx);
 fail1:
        return rc;
}

/* If the interface is supposed to be running but is not, start
 * the hardware and software data path, regular activity for the port
 * (MAC statistics, link polling, etc.) and schedule the port to be
 * reconfigured.  Interrupts must already be enabled.  This function
 * is safe to call multiple times, so long as the NIC is not disabled.
 * Requires the RTNL lock.
 */
static void ef4_start_all(struct ef4_nic *efx)
{
        EF4_ASSERT_RESET_SERIALISED(efx);
        BUG_ON(efx->state == STATE_DISABLED);

        /* Check that it is appropriate to restart the interface. All
         * of these flags are safe to read under just the rtnl lock */
        if (efx->port_enabled || !netif_running(efx->net_dev) ||
            efx->reset_pending)
                return;

        ef4_start_port(efx);
        ef4_start_datapath(efx);

        /* Start the hardware monitor if there is one */
        if (efx->type->monitor != NULL)
                queue_delayed_work(efx->workqueue, &efx->monitor_work,
                                   ef4_monitor_interval);

        efx->type->start_stats(efx);
        efx->type->pull_stats(efx);
        spin_lock_bh(&efx->stats_lock);
        efx->type->update_stats(efx, NULL, NULL);
        spin_unlock_bh(&efx->stats_lock);
}

/* Quiesce the hardware and software data path, and regular activity
 * for the port without bringing the link down.  Safe to call multiple
 * times with the NIC in almost any state, but interrupts should be
 * enabled.  Requires the RTNL lock.
 */
static void ef4_stop_all(struct ef4_nic *efx)
{
        EF4_ASSERT_RESET_SERIALISED(efx);

        /* port_enabled can be read safely under the rtnl lock */
        if (!efx->port_enabled)
                return;

        /* update stats before we go down so we can accurately count
         * rx_nodesc_drops
         */
        efx->type->pull_stats(efx);
        spin_lock_bh(&efx->stats_lock);
        efx->type->update_stats(efx, NULL, NULL);
        spin_unlock_bh(&efx->stats_lock);
        efx->type->stop_stats(efx);
        ef4_stop_port(efx);

        /* Stop the kernel transmit interface.  This is only valid if
         * the device is stopped or detached; otherwise the watchdog
         * may fire immediately.
         */
        WARN_ON(netif_running(efx->net_dev) &&
                netif_device_present(efx->net_dev));
        netif_tx_disable(efx->net_dev);

        ef4_stop_datapath(efx);
}

static void ef4_remove_all(struct ef4_nic *efx)
{
        ef4_remove_channels(efx);
        ef4_remove_filters(efx);
        ef4_remove_port(efx);
        ef4_remove_nic(efx);
}

/**************************************************************************
 *
 * Interrupt moderation
 *
 **************************************************************************/
unsigned int ef4_usecs_to_ticks(struct ef4_nic *efx, unsigned int usecs)
{
        if (usecs == 0)
                return 0;
        if (usecs * 1000 < efx->timer_quantum_ns)
                return 1; /* never round down to 0 */
        return usecs * 1000 / efx->timer_quantum_ns;
}

unsigned int ef4_ticks_to_usecs(struct ef4_nic *efx, unsigned int ticks)
{
        /* We must round up when converting ticks to microseconds
         * because we round down when converting the other way.
         */
        return DIV_ROUND_UP(ticks * efx->timer_quantum_ns, 1000);
}

/* Set interrupt moderation parameters */
int ef4_init_irq_moderation(struct ef4_nic *efx, unsigned int tx_usecs,
                            unsigned int rx_usecs, bool rx_adaptive,
                            bool rx_may_override_tx)
{
        struct ef4_channel *channel;
        unsigned int timer_max_us;

        EF4_ASSERT_RESET_SERIALISED(efx);

        timer_max_us = efx->timer_max_ns / 1000;

        if (tx_usecs > timer_max_us || rx_usecs > timer_max_us)
                return -EINVAL;

        if (tx_usecs != rx_usecs && efx->tx_channel_offset == 0 &&
            !rx_may_override_tx) {
                netif_err(efx, drv, efx->net_dev, "Channels are shared. "
                          "RX and TX IRQ moderation must be equal\n");
                return -EINVAL;
        }

        efx->irq_rx_adaptive = rx_adaptive;
        efx->irq_rx_moderation_us = rx_usecs;
        ef4_for_each_channel(channel, efx) {
                if (ef4_channel_has_rx_queue(channel))
                        channel->irq_moderation_us = rx_usecs;
                else if (ef4_channel_has_tx_queues(channel))
                        channel->irq_moderation_us = tx_usecs;
        }

        return 0;
}

void ef4_get_irq_moderation(struct ef4_nic *efx, unsigned int *tx_usecs,
                            unsigned int *rx_usecs, bool *rx_adaptive)
{
        *rx_adaptive = efx->irq_rx_adaptive;
        *rx_usecs = efx->irq_rx_moderation_us;

        /* If channels are shared between RX and TX, so is IRQ
         * moderation.  Otherwise, IRQ moderation is the same for all
         * TX channels and is not adaptive.
         */
        if (efx->tx_channel_offset == 0) {
                *tx_usecs = *rx_usecs;
        } else {
                struct ef4_channel *tx_channel;

                tx_channel = efx->channel[efx->tx_channel_offset];
                *tx_usecs = tx_channel->irq_moderation_us;
        }
}

/**************************************************************************
 *
 * Hardware monitor
 *
 **************************************************************************/

/* Run periodically off the general workqueue */
static void ef4_monitor(struct work_struct *data)
{
        struct ef4_nic *efx = container_of(data, struct ef4_nic,
                                           monitor_work.work);

        netif_vdbg(efx, timer, efx->net_dev,
                   "hardware monitor executing on CPU %d\n",
                   raw_smp_processor_id());
        BUG_ON(efx->type->monitor == NULL);

        /* If the mac_lock is already held then it is likely a port
         * reconfiguration is already in place, which will likely do
         * most of the work of monitor() anyway. */
        if (mutex_trylock(&efx->mac_lock)) {
                if (efx->port_enabled)
                        efx->type->monitor(efx);
                mutex_unlock(&efx->mac_lock);
        }

        queue_delayed_work(efx->workqueue, &efx->monitor_work,
                           ef4_monitor_interval);
}

/**************************************************************************
 *
 * ioctls
 *

 *************************************************************************/

/* Net device ioctl
 * Context: process, rtnl_lock() held.
 */
static int ef4_ioctl(struct net_device *net_dev, struct ifreq *ifr, int cmd)
{
        struct ef4_nic *efx = netdev_priv(net_dev);
        struct mii_ioctl_data *data = if_mii(ifr);

        /* Convert phy_id from older PRTAD/DEVAD format */
        if ((cmd == SIOCGMIIREG || cmd == SIOCSMIIREG) &&
            (data->phy_id & 0xfc00) == 0x0400)
                data->phy_id ^= MDIO_PHY_ID_C45 | 0x0400;

        return mdio_mii_ioctl(&efx->mdio, data, cmd);
}

/**************************************************************************
 *
 * NAPI interface
 *
 **************************************************************************/

static void ef4_init_napi_channel(struct ef4_channel *channel)
{
        struct ef4_nic *efx = channel->efx;

        channel->napi_dev = efx->net_dev;
        netif_napi_add(channel->napi_dev, &channel->napi_str,
                       ef4_poll, napi_weight);
}

static void ef4_init_napi(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                ef4_init_napi_channel(channel);
}

static void ef4_fini_napi_channel(struct ef4_channel *channel)
{
        if (channel->napi_dev)
                netif_napi_del(&channel->napi_str);

        channel->napi_dev = NULL;
}

static void ef4_fini_napi(struct ef4_nic *efx)
{
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                ef4_fini_napi_channel(channel);
}

/**************************************************************************
 *
 * Kernel netpoll interface
 *
 *************************************************************************/

#ifdef CONFIG_NET_POLL_CONTROLLER

/* Although in the common case interrupts will be disabled, this is not
 * guaranteed. However, all our work happens inside the NAPI callback,
 * so no locking is required.
 */
static void ef4_netpoll(struct net_device *net_dev)
{
        struct ef4_nic *efx = netdev_priv(net_dev);
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                ef4_schedule_channel(channel);
}

#endif

/**************************************************************************
 *
 * Kernel net device interface
 *
 *************************************************************************/

/* Context: process, rtnl_lock() held. */
int ef4_net_open(struct net_device *net_dev)
{
        struct ef4_nic *efx = netdev_priv(net_dev);
        int rc;

        netif_dbg(efx, ifup, efx->net_dev, "opening device on CPU %d\n",
                  raw_smp_processor_id());

        rc = ef4_check_disabled(efx);
        if (rc)
                return rc;
        if (efx->phy_mode & PHY_MODE_SPECIAL)
                return -EBUSY;

        /* Notify the kernel of the link state polled during driver load,
         * before the monitor starts running */
        ef4_link_status_changed(efx);

        ef4_start_all(efx);
        ef4_selftest_async_start(efx);
        return 0;
}

/* Context: process, rtnl_lock() held.
 * Note that the kernel will ignore our return code; this method
 * should really be a void.
 */
int ef4_net_stop(struct net_device *net_dev)
{
        struct ef4_nic *efx = netdev_priv(net_dev);

        netif_dbg(efx, ifdown, efx->net_dev, "closing on CPU %d\n",
                  raw_smp_processor_id());

        /* Stop the device and flush all the channels */
        ef4_stop_all(efx);

        return 0;
}

/* Context: process, dev_base_lock or RTNL held, non-blocking. */
static void ef4_net_stats(struct net_device *net_dev,
                          struct rtnl_link_stats64 *stats)
{
        struct ef4_nic *efx = netdev_priv(net_dev);

        spin_lock_bh(&efx->stats_lock);
        efx->type->update_stats(efx, NULL, stats);
        spin_unlock_bh(&efx->stats_lock);
}

/* Context: netif_tx_lock held, BHs disabled. */
static void ef4_watchdog(struct net_device *net_dev)
{
        struct ef4_nic *efx = netdev_priv(net_dev);

        netif_err(efx, tx_err, efx->net_dev,
                  "TX stuck with port_enabled=%d: resetting channels\n",
                  efx->port_enabled);

        ef4_schedule_reset(efx, RESET_TYPE_TX_WATCHDOG);
}


/* Context: process, rtnl_lock() held. */
static int ef4_change_mtu(struct net_device *net_dev, int new_mtu)
{
        struct ef4_nic *efx = netdev_priv(net_dev);
        int rc;

        rc = ef4_check_disabled(efx);
        if (rc)
                return rc;

        netif_dbg(efx, drv, efx->net_dev, "changing MTU to %d\n", new_mtu);

        ef4_device_detach_sync(efx);
        ef4_stop_all(efx);

        mutex_lock(&efx->mac_lock);
        net_dev->mtu = new_mtu;
        ef4_mac_reconfigure(efx);
        mutex_unlock(&efx->mac_lock);

        ef4_start_all(efx);
        netif_device_attach(efx->net_dev);
        return 0;
}

static int ef4_set_mac_address(struct net_device *net_dev, void *data)
{
        struct ef4_nic *efx = netdev_priv(net_dev);
        struct sockaddr *addr = data;
        u8 *new_addr = addr->sa_data;
        u8 old_addr[6];
        int rc;

        if (!is_valid_ether_addr(new_addr)) {
                netif_err(efx, drv, efx->net_dev,
                          "invalid ethernet MAC address requested: %pM\n",
                          new_addr);
                return -EADDRNOTAVAIL;
        }

        /* save old address */
        ether_addr_copy(old_addr, net_dev->dev_addr);
        ether_addr_copy(net_dev->dev_addr, new_addr);
        if (efx->type->set_mac_address) {
                rc = efx->type->set_mac_address(efx);
                if (rc) {
                        ether_addr_copy(net_dev->dev_addr, old_addr);
                        return rc;
                }
        }

        /* Reconfigure the MAC */
        mutex_lock(&efx->mac_lock);
        ef4_mac_reconfigure(efx);
        mutex_unlock(&efx->mac_lock);

        return 0;
}

/* Context: netif_addr_lock held, BHs disabled. */
static void ef4_set_rx_mode(struct net_device *net_dev)
{
        struct ef4_nic *efx = netdev_priv(net_dev);

        if (efx->port_enabled)
                queue_work(efx->workqueue, &efx->mac_work);
        /* Otherwise ef4_start_port() will do this */
}

static int ef4_set_features(struct net_device *net_dev, netdev_features_t data)
{
        struct ef4_nic *efx = netdev_priv(net_dev);
        int rc;

        /* If disabling RX n-tuple filtering, clear existing filters */
        if (net_dev->features & ~data & NETIF_F_NTUPLE) {
                rc = efx->type->filter_clear_rx(efx, EF4_FILTER_PRI_MANUAL);
                if (rc)
                        return rc;
        }

        /* If Rx VLAN filter is changed, update filters via mac_reconfigure */
        if ((net_dev->features ^ data) & NETIF_F_HW_VLAN_CTAG_FILTER) {
                /* ef4_set_rx_mode() will schedule MAC work to update filters
                 * when a new features are finally set in net_dev.
                 */
                ef4_set_rx_mode(net_dev);
        }

        return 0;
}

static const struct net_device_ops ef4_netdev_ops = {
        .ndo_open               = ef4_net_open,
        .ndo_stop               = ef4_net_stop,
        .ndo_get_stats64        = ef4_net_stats,
        .ndo_tx_timeout         = ef4_watchdog,
        .ndo_start_xmit         = ef4_hard_start_xmit,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_do_ioctl           = ef4_ioctl,
        .ndo_change_mtu         = ef4_change_mtu,
        .ndo_set_mac_address    = ef4_set_mac_address,
        .ndo_set_rx_mode        = ef4_set_rx_mode,
        .ndo_set_features       = ef4_set_features,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = ef4_netpoll,
#endif
        .ndo_setup_tc           = ef4_setup_tc,
#ifdef CONFIG_RFS_ACCEL
        .ndo_rx_flow_steer      = ef4_filter_rfs,
#endif
};

static void ef4_update_name(struct ef4_nic *efx)
{
        strcpy(efx->name, efx->net_dev->name);
        ef4_mtd_rename(efx);
        ef4_set_channel_names(efx);
}

static int ef4_netdev_event(struct notifier_block *this,
                            unsigned long event, void *ptr)
{
        struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);

        if ((net_dev->netdev_ops == &ef4_netdev_ops) &&
            event == NETDEV_CHANGENAME)
                ef4_update_name(netdev_priv(net_dev));

        return NOTIFY_DONE;
}

static struct notifier_block ef4_netdev_notifier = {
        .notifier_call = ef4_netdev_event,
};

static ssize_t
show_phy_type(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct ef4_nic *efx = pci_get_drvdata(to_pci_dev(dev));
        return sprintf(buf, "%d\n", efx->phy_type);
}
static DEVICE_ATTR(phy_type, 0444, show_phy_type, NULL);

static int ef4_register_netdev(struct ef4_nic *efx)
{
        struct net_device *net_dev = efx->net_dev;
        struct ef4_channel *channel;
        int rc;

        net_dev->watchdog_timeo = 5 * HZ;
        net_dev->irq = efx->pci_dev->irq;
        net_dev->netdev_ops = &ef4_netdev_ops;
        net_dev->ethtool_ops = &ef4_ethtool_ops;
        net_dev->gso_max_segs = EF4_TSO_MAX_SEGS;
        net_dev->min_mtu = EF4_MIN_MTU;
        net_dev->max_mtu = EF4_MAX_MTU;

        rtnl_lock();

        /* Enable resets to be scheduled and check whether any were
         * already requested.  If so, the NIC is probably hosed so we
         * abort.
         */
        efx->state = STATE_READY;
        smp_mb(); /* ensure we change state before checking reset_pending */
        if (efx->reset_pending) {
                netif_err(efx, probe, efx->net_dev,
                          "aborting probe due to scheduled reset\n");
                rc = -EIO;
                goto fail_locked;
        }

        rc = dev_alloc_name(net_dev, net_dev->name);
        if (rc < 0)
                goto fail_locked;
        ef4_update_name(efx);

        /* Always start with carrier off; PHY events will detect the link */
        netif_carrier_off(net_dev);

        rc = register_netdevice(net_dev);
        if (rc)
                goto fail_locked;

        ef4_for_each_channel(channel, efx) {
                struct ef4_tx_queue *tx_queue;
                ef4_for_each_channel_tx_queue(tx_queue, channel)
                        ef4_init_tx_queue_core_txq(tx_queue);
        }

        ef4_associate(efx);

        rtnl_unlock();

        rc = device_create_file(&efx->pci_dev->dev, &dev_attr_phy_type);
        if (rc) {
                netif_err(efx, drv, efx->net_dev,
                          "failed to init net dev attributes\n");
                goto fail_registered;
        }
        return 0;

fail_registered:
        rtnl_lock();
        ef4_dissociate(efx);
        unregister_netdevice(net_dev);
fail_locked:
        efx->state = STATE_UNINIT;
        rtnl_unlock();
        netif_err(efx, drv, efx->net_dev, "could not register net dev\n");
        return rc;
}

static void ef4_unregister_netdev(struct ef4_nic *efx)
{
        if (!efx->net_dev)
                return;

        BUG_ON(netdev_priv(efx->net_dev) != efx);

        if (ef4_dev_registered(efx)) {
                strlcpy(efx->name, pci_name(efx->pci_dev), sizeof(efx->name));
                device_remove_file(&efx->pci_dev->dev, &dev_attr_phy_type);
                unregister_netdev(efx->net_dev);
        }
}

/**************************************************************************
 *
 * Device reset and suspend
 *
 **************************************************************************/

/* Tears down the entire software state and most of the hardware state
 * before reset.  */
void ef4_reset_down(struct ef4_nic *efx, enum reset_type method)
{
        EF4_ASSERT_RESET_SERIALISED(efx);

        ef4_stop_all(efx);
        ef4_disable_interrupts(efx);

        mutex_lock(&efx->mac_lock);
        if (efx->port_initialized && method != RESET_TYPE_INVISIBLE &&
            method != RESET_TYPE_DATAPATH)
                efx->phy_op->fini(efx);
        efx->type->fini(efx);
}

/* This function will always ensure that the locks acquired in
 * ef4_reset_down() are released. A failure return code indicates
 * that we were unable to reinitialise the hardware, and the
 * driver should be disabled. If ok is false, then the rx and tx
 * engines are not restarted, pending a RESET_DISABLE. */
int ef4_reset_up(struct ef4_nic *efx, enum reset_type method, bool ok)
{
        int rc;

        EF4_ASSERT_RESET_SERIALISED(efx);

        /* Ensure that SRAM is initialised even if we're disabling the device */
        rc = efx->type->init(efx);
        if (rc) {
                netif_err(efx, drv, efx->net_dev, "failed to initialise NIC\n");
                goto fail;
        }

        if (!ok)
                goto fail;

        if (efx->port_initialized && method != RESET_TYPE_INVISIBLE &&
            method != RESET_TYPE_DATAPATH) {
                rc = efx->phy_op->init(efx);
                if (rc)
                        goto fail;
                rc = efx->phy_op->reconfigure(efx);
                if (rc && rc != -EPERM)
                        netif_err(efx, drv, efx->net_dev,
                                  "could not restore PHY settings\n");
        }

        rc = ef4_enable_interrupts(efx);
        if (rc)
                goto fail;

        down_read(&efx->filter_sem);
        ef4_restore_filters(efx);
        up_read(&efx->filter_sem);

        mutex_unlock(&efx->mac_lock);

        ef4_start_all(efx);

        return 0;

fail:
        efx->port_initialized = false;

        mutex_unlock(&efx->mac_lock);

        return rc;
}

/* Reset the NIC using the specified method.  Note that the reset may
 * fail, in which case the card will be left in an unusable state.
 *
 * Caller must hold the rtnl_lock.
 */
int ef4_reset(struct ef4_nic *efx, enum reset_type method)
{
        int rc, rc2;
        bool disabled;

        netif_info(efx, drv, efx->net_dev, "resetting (%s)\n",
                   RESET_TYPE(method));

        ef4_device_detach_sync(efx);
        ef4_reset_down(efx, method);

        rc = efx->type->reset(efx, method);
        if (rc) {
                netif_err(efx, drv, efx->net_dev, "failed to reset hardware\n");
                goto out;
        }

        /* Clear flags for the scopes we covered.  We assume the NIC and
         * driver are now quiescent so that there is no race here.
         */
        if (method < RESET_TYPE_MAX_METHOD)
                efx->reset_pending &= -(1 << (method + 1));
        else /* it doesn't fit into the well-ordered scope hierarchy */
                __clear_bit(method, &efx->reset_pending);

        /* Reinitialise bus-mastering, which may have been turned off before
         * the reset was scheduled. This is still appropriate, even in the
         * RESET_TYPE_DISABLE since this driver generally assumes the hardware
         * can respond to requests. */
        pci_set_master(efx->pci_dev);

out:
        /* Leave device stopped if necessary */
        disabled = rc ||
                method == RESET_TYPE_DISABLE ||
                method == RESET_TYPE_RECOVER_OR_DISABLE;
        rc2 = ef4_reset_up(efx, method, !disabled);
        if (rc2) {
                disabled = true;
                if (!rc)
                        rc = rc2;
        }

        if (disabled) {
                dev_close(efx->net_dev);
                netif_err(efx, drv, efx->net_dev, "has been disabled\n");
                efx->state = STATE_DISABLED;
        } else {
                netif_dbg(efx, drv, efx->net_dev, "reset complete\n");
                netif_device_attach(efx->net_dev);
        }
        return rc;
}

/* Try recovery mechanisms.
 * For now only EEH is supported.
 * Returns 0 if the recovery mechanisms are unsuccessful.
 * Returns a non-zero value otherwise.
 */
int ef4_try_recovery(struct ef4_nic *efx)
{
#ifdef CONFIG_EEH
        /* A PCI error can occur and not be seen by EEH because nothing
         * happens on the PCI bus. In this case the driver may fail and
         * schedule a 'recover or reset', leading to this recovery handler.
         * Manually call the eeh failure check function.
         */
        struct eeh_dev *eehdev = pci_dev_to_eeh_dev(efx->pci_dev);
        if (eeh_dev_check_failure(eehdev)) {
                /* The EEH mechanisms will handle the error and reset the
                 * device if necessary.
                 */
                return 1;
        }
#endif
        return 0;
}

/* The worker thread exists so that code that cannot sleep can
 * schedule a reset for later.
 */
static void ef4_reset_work(struct work_struct *data)
{
        struct ef4_nic *efx = container_of(data, struct ef4_nic, reset_work);
        unsigned long pending;
        enum reset_type method;

        pending = ACCESS_ONCE(efx->reset_pending);
        method = fls(pending) - 1;

        if ((method == RESET_TYPE_RECOVER_OR_DISABLE ||
             method == RESET_TYPE_RECOVER_OR_ALL) &&
            ef4_try_recovery(efx))
                return;

        if (!pending)
                return;

        rtnl_lock();

        /* We checked the state in ef4_schedule_reset() but it may
         * have changed by now.  Now that we have the RTNL lock,
         * it cannot change again.
         */
        if (efx->state == STATE_READY)
                (void)ef4_reset(efx, method);

        rtnl_unlock();
}

void ef4_schedule_reset(struct ef4_nic *efx, enum reset_type type)
{
        enum reset_type method;

        if (efx->state == STATE_RECOVERY) {
                netif_dbg(efx, drv, efx->net_dev,
                          "recovering: skip scheduling %s reset\n",
                          RESET_TYPE(type));
                return;
        }

        switch (type) {
        case RESET_TYPE_INVISIBLE:
        case RESET_TYPE_ALL:
        case RESET_TYPE_RECOVER_OR_ALL:
        case RESET_TYPE_WORLD:
        case RESET_TYPE_DISABLE:
        case RESET_TYPE_RECOVER_OR_DISABLE:
        case RESET_TYPE_DATAPATH:
                method = type;
                netif_dbg(efx, drv, efx->net_dev, "scheduling %s reset\n",
                          RESET_TYPE(method));
                break;
        default:
                method = efx->type->map_reset_reason(type);
                netif_dbg(efx, drv, efx->net_dev,
                          "scheduling %s reset for %s\n",
                          RESET_TYPE(method), RESET_TYPE(type));
                break;
        }

        set_bit(method, &efx->reset_pending);
        smp_mb(); /* ensure we change reset_pending before checking state */

        /* If we're not READY then just leave the flags set as the cue
         * to abort probing or reschedule the reset later.
         */
        if (ACCESS_ONCE(efx->state) != STATE_READY)
                return;

        queue_work(reset_workqueue, &efx->reset_work);
}

/**************************************************************************
 *
 * List of NICs we support
 *
 **************************************************************************/

/* PCI device ID table */
static const struct pci_device_id ef4_pci_table[] = {
        {PCI_DEVICE(PCI_VENDOR_ID_SOLARFLARE,
                    PCI_DEVICE_ID_SOLARFLARE_SFC4000A_0),
         .driver_data = (unsigned long) &falcon_a1_nic_type},
        {PCI_DEVICE(PCI_VENDOR_ID_SOLARFLARE,
                    PCI_DEVICE_ID_SOLARFLARE_SFC4000B),
         .driver_data = (unsigned long) &falcon_b0_nic_type},
        {0}                     /* end of list */
};

/**************************************************************************
 *
 * Dummy PHY/MAC operations
 *
 * Can be used for some unimplemented operations
 * Needed so all function pointers are valid and do not have to be tested
 * before use
 *
 **************************************************************************/
int ef4_port_dummy_op_int(struct ef4_nic *efx)
{
        return 0;
}
void ef4_port_dummy_op_void(struct ef4_nic *efx) {}

static bool ef4_port_dummy_op_poll(struct ef4_nic *efx)
{
        return false;
}

static const struct ef4_phy_operations ef4_dummy_phy_operations = {
        .init            = ef4_port_dummy_op_int,
        .reconfigure     = ef4_port_dummy_op_int,
        .poll            = ef4_port_dummy_op_poll,
        .fini            = ef4_port_dummy_op_void,
};

/**************************************************************************
 *
 * Data housekeeping
 *
 **************************************************************************/

/* This zeroes out and then fills in the invariants in a struct
 * ef4_nic (including all sub-structures).
 */
static int ef4_init_struct(struct ef4_nic *efx,
                           struct pci_dev *pci_dev, struct net_device *net_dev)
{
        int i;

        /* Initialise common structures */
        INIT_LIST_HEAD(&efx->node);
        INIT_LIST_HEAD(&efx->secondary_list);
        spin_lock_init(&efx->biu_lock);
#ifdef CONFIG_SFC_FALCON_MTD
        INIT_LIST_HEAD(&efx->mtd_list);
#endif
        INIT_WORK(&efx->reset_work, ef4_reset_work);
        INIT_DELAYED_WORK(&efx->monitor_work, ef4_monitor);
        INIT_DELAYED_WORK(&efx->selftest_work, ef4_selftest_async_work);
        efx->pci_dev = pci_dev;
        efx->msg_enable = debug;
        efx->state = STATE_UNINIT;
        strlcpy(efx->name, pci_name(pci_dev), sizeof(efx->name));

        efx->net_dev = net_dev;
        efx->rx_prefix_size = efx->type->rx_prefix_size;
        efx->rx_ip_align =
                NET_IP_ALIGN ? (efx->rx_prefix_size + NET_IP_ALIGN) % 4 : 0;
        efx->rx_packet_hash_offset =
                efx->type->rx_hash_offset - efx->type->rx_prefix_size;
        efx->rx_packet_ts_offset =
                efx->type->rx_ts_offset - efx->type->rx_prefix_size;
        spin_lock_init(&efx->stats_lock);
        mutex_init(&efx->mac_lock);
        efx->phy_op = &ef4_dummy_phy_operations;
        efx->mdio.dev = net_dev;
        INIT_WORK(&efx->mac_work, ef4_mac_work);
        init_waitqueue_head(&efx->flush_wq);

        for (i = 0; i < EF4_MAX_CHANNELS; i++) {
                efx->channel[i] = ef4_alloc_channel(efx, i, NULL);
                if (!efx->channel[i])
                        goto fail;
                efx->msi_context[i].efx = efx;
                efx->msi_context[i].index = i;
        }

        /* Higher numbered interrupt modes are less capable! */
        efx->interrupt_mode = max(efx->type->max_interrupt_mode,
                                  interrupt_mode);

        /* Would be good to use the net_dev name, but we're too early */
        snprintf(efx->workqueue_name, sizeof(efx->workqueue_name), "sfc%s",
                 pci_name(pci_dev));
        efx->workqueue = create_singlethread_workqueue(efx->workqueue_name);
        if (!efx->workqueue)
                goto fail;

        return 0;

fail:
        ef4_fini_struct(efx);
        return -ENOMEM;
}

static void ef4_fini_struct(struct ef4_nic *efx)
{
        int i;

        for (i = 0; i < EF4_MAX_CHANNELS; i++)
                kfree(efx->channel[i]);

        kfree(efx->vpd_sn);

        if (efx->workqueue) {
                destroy_workqueue(efx->workqueue);
                efx->workqueue = NULL;
        }
}

void ef4_update_sw_stats(struct ef4_nic *efx, u64 *stats)
{
        u64 n_rx_nodesc_trunc = 0;
        struct ef4_channel *channel;

        ef4_for_each_channel(channel, efx)
                n_rx_nodesc_trunc += channel->n_rx_nodesc_trunc;
        stats[GENERIC_STAT_rx_nodesc_trunc] = n_rx_nodesc_trunc;
        stats[GENERIC_STAT_rx_noskb_drops] = atomic_read(&efx->n_rx_noskb_drops);
}

/**************************************************************************
 *
 * PCI interface
 *
 **************************************************************************/

/* Main body of final NIC shutdown code
 * This is called only at module unload (or hotplug removal).
 */
static void ef4_pci_remove_main(struct ef4_nic *efx)
{
        /* Flush reset_work. It can no longer be scheduled since we
         * are not READY.
         */
        BUG_ON(efx->state == STATE_READY);
        cancel_work_sync(&efx->reset_work);

        ef4_disable_interrupts(efx);
        ef4_nic_fini_interrupt(efx);
        ef4_fini_port(efx);
        efx->type->fini(efx);
        ef4_fini_napi(efx);
        ef4_remove_all(efx);
}

/* Final NIC shutdown
 * This is called only at module unload (or hotplug removal).  A PF can call
 * this on its VFs to ensure they are unbound first.
 */
static void ef4_pci_remove(struct pci_dev *pci_dev)
{
        struct ef4_nic *efx;

        efx = pci_get_drvdata(pci_dev);
        if (!efx)
                return;

        /* Mark the NIC as fini, then stop the interface */
        rtnl_lock();
        ef4_dissociate(efx);
        dev_close(efx->net_dev);
        ef4_disable_interrupts(efx);
        efx->state = STATE_UNINIT;
        rtnl_unlock();

        ef4_unregister_netdev(efx);

        ef4_mtd_remove(efx);

        ef4_pci_remove_main(efx);

        ef4_fini_io(efx);
        netif_dbg(efx, drv, efx->net_dev, "shutdown successful\n");

        ef4_fini_struct(efx);
        free_netdev(efx->net_dev);

        pci_disable_pcie_error_reporting(pci_dev);
};

/* NIC VPD information
 * Called during probe to display the part number of the
 * installed NIC.  VPD is potentially very large but this should
 * always appear within the first 512 bytes.
 */
#define SFC_VPD_LEN 512
static void ef4_probe_vpd_strings(struct ef4_nic *efx)
{
        struct pci_dev *dev = efx->pci_dev;
        char vpd_data[SFC_VPD_LEN];
        ssize_t vpd_size;
        int ro_start, ro_size, i, j;

        /* Get the vpd data from the device */
        vpd_size = pci_read_vpd(dev, 0, sizeof(vpd_data), vpd_data);
        if (vpd_size <= 0) {
                netif_err(efx, drv, efx->net_dev, "Unable to read VPD\n");
                return;
        }

        /* Get the Read only section */
        ro_start = pci_vpd_find_tag(vpd_data, 0, vpd_size, PCI_VPD_LRDT_RO_DATA);
        if (ro_start < 0) {
                netif_err(efx, drv, efx->net_dev, "VPD Read-only not found\n");
                return;
        }

        ro_size = pci_vpd_lrdt_size(&vpd_data[ro_start]);
        j = ro_size;
        i = ro_start + PCI_VPD_LRDT_TAG_SIZE;
        if (i + j > vpd_size)
                j = vpd_size - i;

        /* Get the Part number */
        i = pci_vpd_find_info_keyword(vpd_data, i, j, "PN");
        if (i < 0) {
                netif_err(efx, drv, efx->net_dev, "Part number not found\n");
                return;
        }

        j = pci_vpd_info_field_size(&vpd_data[i]);
        i += PCI_VPD_INFO_FLD_HDR_SIZE;
        if (i + j > vpd_size) {
                netif_err(efx, drv, efx->net_dev, "Incomplete part number\n");
                return;
        }

        netif_info(efx, drv, efx->net_dev,
                   "Part Number : %.*s\n", j, &vpd_data[i]);

        i = ro_start + PCI_VPD_LRDT_TAG_SIZE;
        j = ro_size;
        i = pci_vpd_find_info_keyword(vpd_data, i, j, "SN");
        if (i < 0) {
                netif_err(efx, drv, efx->net_dev, "Serial number not found\n");
                return;
        }

        j = pci_vpd_info_field_size(&vpd_data[i]);
        i += PCI_VPD_INFO_FLD_HDR_SIZE;
        if (i + j > vpd_size) {
                netif_err(efx, drv, efx->net_dev, "Incomplete serial number\n");
                return;
        }

        efx->vpd_sn = kmalloc(j + 1, GFP_KERNEL);
        if (!efx->vpd_sn)
                return;

        snprintf(efx->vpd_sn, j + 1, "%s", &vpd_data[i]);
}


/* Main body of NIC initialisation
 * This is called at module load (or hotplug insertion, theoretically).
 */
static int ef4_pci_probe_main(struct ef4_nic *efx)
{
        int rc;

        /* Do start-of-day initialisation */
        rc = ef4_probe_all(efx);
        if (rc)
                goto fail1;

        ef4_init_napi(efx);

        rc = efx->type->init(efx);
        if (rc) {
                netif_err(efx, probe, efx->net_dev,
                          "failed to initialise NIC\n");
                goto fail3;
        }

        rc = ef4_init_port(efx);
        if (rc) {
                netif_err(efx, probe, efx->net_dev,
                          "failed to initialise port\n");
                goto fail4;
        }

        rc = ef4_nic_init_interrupt(efx);
        if (rc)
                goto fail5;
        rc = ef4_enable_interrupts(efx);
        if (rc)
                goto fail6;

        return 0;

 fail6:
        ef4_nic_fini_interrupt(efx);
 fail5:
        ef4_fini_port(efx);
 fail4:
        efx->type->fini(efx);
 fail3:
        ef4_fini_napi(efx);
        ef4_remove_all(efx);
 fail1:
        return rc;
}

/* NIC initialisation
 *
 * This is called at module load (or hotplug insertion,
 * theoretically).  It sets up PCI mappings, resets the NIC,
 * sets up and registers the network devices with the kernel and hooks
 * the interrupt service routine.  It does not prepare the device for
 * transmission; this is left to the first time one of the network
 * interfaces is brought up (i.e. ef4_net_open).
 */
static int ef4_pci_probe(struct pci_dev *pci_dev,
                         const struct pci_device_id *entry)
{
        struct net_device *net_dev;
        struct ef4_nic *efx;
        int rc;

        /* Allocate and initialise a struct net_device and struct ef4_nic */
        net_dev = alloc_etherdev_mqs(sizeof(*efx), EF4_MAX_CORE_TX_QUEUES,
                                     EF4_MAX_RX_QUEUES);
        if (!net_dev)
                return -ENOMEM;
        efx = netdev_priv(net_dev);
        efx->type = (const struct ef4_nic_type *) entry->driver_data;
        efx->fixed_features |= NETIF_F_HIGHDMA;

        pci_set_drvdata(pci_dev, efx);
        SET_NETDEV_DEV(net_dev, &pci_dev->dev);
        rc = ef4_init_struct(efx, pci_dev, net_dev);
        if (rc)
                goto fail1;

        netif_info(efx, probe, efx->net_dev,
                   "Solarflare NIC detected\n");

        ef4_probe_vpd_strings(efx);

        /* Set up basic I/O (BAR mappings etc) */
        rc = ef4_init_io(efx);
        if (rc)
                goto fail2;

        rc = ef4_pci_probe_main(efx);
        if (rc)
                goto fail3;

        net_dev->features |= (efx->type->offload_features | NETIF_F_SG |
                              NETIF_F_RXCSUM);
        /* Mask for features that also apply to VLAN devices */
        net_dev->vlan_features |= (NETIF_F_HW_CSUM | NETIF_F_SG |
                                   NETIF_F_HIGHDMA | NETIF_F_RXCSUM);

        net_dev->hw_features = net_dev->features & ~efx->fixed_features;

        /* Disable VLAN filtering by default.  It may be enforced if
         * the feature is fixed (i.e. VLAN filters are required to
         * receive VLAN tagged packets due to vPort restrictions).
         */
        net_dev->features &= ~NETIF_F_HW_VLAN_CTAG_FILTER;
        net_dev->features |= efx->fixed_features;

        rc = ef4_register_netdev(efx);
        if (rc)
                goto fail4;