sfc: Correct interrupt timer quantum for Siena (normal and turbo mode)

[deliverable/linux.git] / drivers / net / ethernet / sfc / efx.c

/****************************************************************************
 * Driver for Solarflare Solarstorm network controllers and boards
 * Copyright 2005-2006 Fen Systems Ltd.
 * Copyright 2005-2011 Solarflare Communications Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */

#include <linux/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/crc32.h>
#include <linux/ethtool.h>
#include <linux/topology.h>
#include <linux/gfp.h>
#include <linux/cpu_rmap.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"

#include "mcdi.h"
#include "workarounds.h"

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

/* Loopback mode names (see LOOPBACK_MODE()) */
const unsigned int efx_loopback_mode_max = LOOPBACK_MAX;
const char *const efx_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 efx_reset_type_max = RESET_TYPE_MAX;
const char *const efx_reset_type_names[] = {
        [RESET_TYPE_INVISIBLE]     = "INVISIBLE",
        [RESET_TYPE_ALL]           = "ALL",
        [RESET_TYPE_WORLD]         = "WORLD",
        [RESET_TYPE_DISABLE]       = "DISABLE",
        [RESET_TYPE_TX_WATCHDOG]   = "TX_WATCHDOG",
        [RESET_TYPE_INT_ERROR]     = "INT_ERROR",
        [RESET_TYPE_RX_RECOVERY]   = "RX_RECOVERY",
        [RESET_TYPE_RX_DESC_FETCH] = "RX_DESC_FETCH",
        [RESET_TYPE_TX_DESC_FETCH] = "TX_DESC_FETCH",
        [RESET_TYPE_TX_SKIP]       = "TX_SKIP",
        [RESET_TYPE_MC_FAILURE]    = "MC_FAILURE",
};

#define EFX_MAX_MTU (9 * 1024)

/* 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
 * efx_reset_work() acquires the rtnl lock, so resets are naturally serialised.
 */
static struct workqueue_struct *reset_workqueue;

/**************************************************************************
 *
 * 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
 */
static unsigned int separate_tx_channels;
module_param(separate_tx_channels, uint, 0444);
MODULE_PARM_DESC(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.
 */
static unsigned int efx_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 int phy_flash_cfg;
module_param(phy_flash_cfg, int, 0644);
MODULE_PARM_DESC(phy_flash_cfg, "Set PHYs into reflash mode initially");

static unsigned irq_adapt_low_thresh = 10000;
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 = 20000;
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 void efx_remove_channels(struct efx_nic *efx);
static void efx_remove_port(struct efx_nic *efx);
static void efx_init_napi(struct efx_nic *efx);
static void efx_fini_napi(struct efx_nic *efx);
static void efx_fini_napi_channel(struct efx_channel *channel);
static void efx_fini_struct(struct efx_nic *efx);
static void efx_start_all(struct efx_nic *efx);
static void efx_stop_all(struct efx_nic *efx);

#define EFX_ASSERT_RESET_SERIALISED(efx)                \
        do {                                            \
                if ((efx->state == STATE_RUNNING) ||    \
                    (efx->state == STATE_DISABLED))     \
                        ASSERT_RTNL();                  \
        } while (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 efx_process_channel(struct efx_channel *channel, int budget)
{
        struct efx_nic *efx = channel->efx;
        int spent;

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

        spent = efx_nic_process_eventq(channel, budget);
        if (spent == 0)
                return 0;

        /* Deliver last RX packet. */
        if (channel->rx_pkt) {
                __efx_rx_packet(channel, channel->rx_pkt,
                                channel->rx_pkt_csummed);
                channel->rx_pkt = NULL;
        }

        efx_rx_strategy(channel);

        efx_fast_push_rx_descriptors(efx_channel_get_rx_queue(channel));

        return spent;
}

/* Mark channel as finished processing
 *
 * Note that since we will not receive further interrupts for this
 * channel before we finish processing and call the eventq_read_ack()
 * method, there is no need to use the interrupt hold-off timers.
 */
static inline void efx_channel_processed(struct efx_channel *channel)
{
        /* The interrupt handler for this channel may set work_pending
         * as soon as we acknowledge the events we've seen.  Make sure
         * it's cleared before then. */
        channel->work_pending = false;
        smp_wmb();

        efx_nic_eventq_read_ack(channel);
}

/* NAPI poll handler
 *
 * NAPI guarantees serialisation of polls of the same device, which
 * provides the guarantee required by efx_process_channel().
 */
static int efx_poll(struct napi_struct *napi, int budget)
{
        struct efx_channel *channel =
                container_of(napi, struct efx_channel, napi_str);
        struct efx_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 = efx_process_channel(channel, budget);

        if (spent < budget) {
                if (channel->channel < efx->n_rx_channels &&
                    efx->irq_rx_adaptive &&
                    unlikely(++channel->irq_count == 1000)) {
                        if (unlikely(channel->irq_mod_score <
                                     irq_adapt_low_thresh)) {
                                if (channel->irq_moderation > 1) {
                                        channel->irq_moderation -= 1;
                                        efx->type->push_irq_moderation(channel);
                                }
                        } else if (unlikely(channel->irq_mod_score >
                                            irq_adapt_high_thresh)) {
                                if (channel->irq_moderation <
                                    efx->irq_rx_moderation) {
                                        channel->irq_moderation += 1;
                                        efx->type->push_irq_moderation(channel);
                                }
                        }
                        channel->irq_count = 0;
                        channel->irq_mod_score = 0;
                }

                efx_filter_rfs_expire(channel);

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

        return spent;
}

/* Process the eventq of the specified channel immediately on this CPU
 *
 * Disable hardware generated interrupts, wait for any existing
 * processing to finish, then directly poll (and ack ) the eventq.
 * Finally reenable NAPI and interrupts.
 *
 * This is for use only during a loopback self-test.  It must not
 * deliver any packets up the stack as this can result in deadlock.
 */
void efx_process_channel_now(struct efx_channel *channel)
{
        struct efx_nic *efx = channel->efx;

        BUG_ON(channel->channel >= efx->n_channels);
        BUG_ON(!channel->enabled);
        BUG_ON(!efx->loopback_selftest);

        /* Disable interrupts and wait for ISRs to complete */
        efx_nic_disable_interrupts(efx);
        if (efx->legacy_irq) {
                synchronize_irq(efx->legacy_irq);
                efx->legacy_irq_enabled = false;
        }
        if (channel->irq)
                synchronize_irq(channel->irq);

        /* Wait for any NAPI processing to complete */
        napi_disable(&channel->napi_str);

        /* Poll the channel */
        efx_process_channel(channel, channel->eventq_mask + 1);

        /* Ack the eventq. This may cause an interrupt to be generated
         * when they are reenabled */
        efx_channel_processed(channel);

        napi_enable(&channel->napi_str);
        if (efx->legacy_irq)
                efx->legacy_irq_enabled = true;
        efx_nic_enable_interrupts(efx);
}

/* 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 efx_probe_eventq(struct efx_channel *channel)
{
        struct efx_nic *efx = channel->efx;
        unsigned long entries;

        netif_dbg(channel->efx, probe, channel->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);
        EFX_BUG_ON_PARANOID(entries > EFX_MAX_EVQ_SIZE);
        channel->eventq_mask = max(entries, EFX_MIN_EVQ_SIZE) - 1;

        return efx_nic_probe_eventq(channel);
}

/* Prepare channel's event queue */
static void efx_init_eventq(struct efx_channel *channel)
{
        netif_dbg(channel->efx, drv, channel->efx->net_dev,
                  "chan %d init event queue\n", channel->channel);

        channel->eventq_read_ptr = 0;

        efx_nic_init_eventq(channel);
}

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

        efx_nic_fini_eventq(channel);
}

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

        efx_nic_remove_eventq(channel);
}

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

/* Allocate and initialise a channel structure, optionally copying
 * parameters (but not resources) from an old channel structure. */
static struct efx_channel *
efx_alloc_channel(struct efx_nic *efx, int i, struct efx_channel *old_channel)
{
        struct efx_channel *channel;
        struct efx_rx_queue *rx_queue;
        struct efx_tx_queue *tx_queue;
        int j;

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

                *channel = *old_channel;

                channel->napi_dev = NULL;
                memset(&channel->eventq, 0, sizeof(channel->eventq));

                rx_queue = &channel->rx_queue;
                rx_queue->buffer = NULL;
                memset(&rx_queue->rxd, 0, sizeof(rx_queue->rxd));

                for (j = 0; j < EFX_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));
                }
        } else {
                channel = kzalloc(sizeof(*channel), GFP_KERNEL);
                if (!channel)
                        return NULL;

                channel->efx = efx;
                channel->channel = i;

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

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

        return channel;
}

static int efx_probe_channel(struct efx_channel *channel)
{
        struct efx_tx_queue *tx_queue;
        struct efx_rx_queue *rx_queue;
        int rc;

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

        rc = efx_probe_eventq(channel);
        if (rc)
                goto fail1;

        efx_for_each_channel_tx_queue(tx_queue, channel) {
                rc = efx_probe_tx_queue(tx_queue);
                if (rc)
                        goto fail2;
        }

        efx_for_each_channel_rx_queue(rx_queue, channel) {
                rc = efx_probe_rx_queue(rx_queue);
                if (rc)
                        goto fail3;
        }

        channel->n_rx_frm_trunc = 0;

        return 0;

 fail3:
        efx_for_each_channel_rx_queue(rx_queue, channel)
                efx_remove_rx_queue(rx_queue);
 fail2:
        efx_for_each_channel_tx_queue(tx_queue, channel)
                efx_remove_tx_queue(tx_queue);
 fail1:
        return rc;
}


static void efx_set_channel_names(struct efx_nic *efx)
{
        struct efx_channel *channel;
        const char *type = "";
        int number;

        efx_for_each_channel(channel, efx) {
                number = channel->channel;
                if (efx->n_channels > efx->n_rx_channels) {
                        if (channel->channel < efx->n_rx_channels) {
                                type = "-rx";
                        } else {
                                type = "-tx";
                                number -= efx->n_rx_channels;
                        }
                }
                snprintf(efx->channel_name[channel->channel],
                         sizeof(efx->channel_name[0]),
                         "%s%s-%d", efx->name, type, number);
        }
}

static int efx_probe_channels(struct efx_nic *efx)
{
        struct efx_channel *channel;
        int rc;

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

        efx_for_each_channel(channel, efx) {
                rc = efx_probe_channel(channel);
                if (rc) {
                        netif_err(efx, probe, efx->net_dev,
                                  "failed to create channel %d\n",
                                  channel->channel);
                        goto fail;
                }
        }
        efx_set_channel_names(efx);

        return 0;

fail:
        efx_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 efx_init_channels(struct efx_nic *efx)
{
        struct efx_tx_queue *tx_queue;
        struct efx_rx_queue *rx_queue;
        struct efx_channel *channel;

        /* Calculate the rx buffer allocation parameters required to
         * support the current MTU, including padding for header
         * alignment and overruns.
         */
        efx->rx_buffer_len = (max(EFX_PAGE_IP_ALIGN, NET_IP_ALIGN) +
                              EFX_MAX_FRAME_LEN(efx->net_dev->mtu) +
                              efx->type->rx_buffer_hash_size +
                              efx->type->rx_buffer_padding);
        efx->rx_buffer_order = get_order(efx->rx_buffer_len +
                                         sizeof(struct efx_rx_page_state));

        /* Initialise the channels */
        efx_for_each_channel(channel, efx) {
                netif_dbg(channel->efx, drv, channel->efx->net_dev,
                          "init chan %d\n", channel->channel);

                efx_init_eventq(channel);

                efx_for_each_channel_tx_queue(tx_queue, channel)
                        efx_init_tx_queue(tx_queue);

                /* The rx buffer allocation strategy is MTU dependent */
                efx_rx_strategy(channel);

                efx_for_each_channel_rx_queue(rx_queue, channel)
                        efx_init_rx_queue(rx_queue);

                WARN_ON(channel->rx_pkt != NULL);
                efx_rx_strategy(channel);
        }
}

/* This enables event queue processing and packet transmission.
 *
 * Note that this function is not allowed to fail, since that would
 * introduce too much complexity into the suspend/resume path.
 */
static void efx_start_channel(struct efx_channel *channel)
{
        struct efx_rx_queue *rx_queue;

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

        /* The interrupt handler for this channel may set work_pending
         * as soon as we enable it.  Make sure it's cleared before
         * then.  Similarly, make sure it sees the enabled flag set. */
        channel->work_pending = false;
        channel->enabled = true;
        smp_wmb();

        /* Fill the queues before enabling NAPI */
        efx_for_each_channel_rx_queue(rx_queue, channel)
                efx_fast_push_rx_descriptors(rx_queue);

        napi_enable(&channel->napi_str);
}

/* This disables event queue processing and packet transmission.
 * This function does not guarantee that all queue processing
 * (e.g. RX refill) is complete.
 */
static void efx_stop_channel(struct efx_channel *channel)
{
        if (!channel->enabled)
                return;

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

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

static void efx_fini_channels(struct efx_nic *efx)
{
        struct efx_channel *channel;
        struct efx_tx_queue *tx_queue;
        struct efx_rx_queue *rx_queue;
        int rc;

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

        rc = efx_nic_flush_queues(efx);
        if (rc && EFX_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");
                efx_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");
        }

        efx_for_each_channel(channel, efx) {
                netif_dbg(channel->efx, drv, channel->efx->net_dev,
                          "shut down chan %d\n", channel->channel);

                efx_for_each_channel_rx_queue(rx_queue, channel)
                        efx_fini_rx_queue(rx_queue);
                efx_for_each_possible_channel_tx_queue(tx_queue, channel)
                        efx_fini_tx_queue(tx_queue);
                efx_fini_eventq(channel);
        }
}

static void efx_remove_channel(struct efx_channel *channel)
{
        struct efx_tx_queue *tx_queue;
        struct efx_rx_queue *rx_queue;

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

        efx_for_each_channel_rx_queue(rx_queue, channel)
                efx_remove_rx_queue(rx_queue);
        efx_for_each_possible_channel_tx_queue(tx_queue, channel)
                efx_remove_tx_queue(tx_queue);
        efx_remove_eventq(channel);
}

static void efx_remove_channels(struct efx_nic *efx)
{
        struct efx_channel *channel;

        efx_for_each_channel(channel, efx)
                efx_remove_channel(channel);
}

int
efx_realloc_channels(struct efx_nic *efx, u32 rxq_entries, u32 txq_entries)
{
        struct efx_channel *other_channel[EFX_MAX_CHANNELS], *channel;
        u32 old_rxq_entries, old_txq_entries;
        unsigned i;
        int rc;

        efx_stop_all(efx);
        efx_fini_channels(efx);

        /* Clone channels */
        memset(other_channel, 0, sizeof(other_channel));
        for (i = 0; i < efx->n_channels; i++) {
                channel = efx_alloc_channel(efx, i, efx->channel[i]);
                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;
        }

        rc = efx_probe_channels(efx);
        if (rc)
                goto rollback;

        efx_init_napi(efx);

        /* Destroy old channels */
        for (i = 0; i < efx->n_channels; i++) {
                efx_fini_napi_channel(other_channel[i]);
                efx_remove_channel(other_channel[i]);
        }
out:
        /* Free unused channel structures */
        for (i = 0; i < efx->n_channels; i++)
                kfree(other_channel[i]);

        efx_init_channels(efx);
        efx_start_all(efx);
        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 efx_schedule_slow_fill(struct efx_rx_queue *rx_queue)
{
        mod_timer(&rx_queue->slow_fill, jiffies + msecs_to_jiffies(100));
}

/**************************************************************************
 *
 * 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 efx_link_status_changed(struct efx_nic *efx)
{
        struct efx_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)%s\n",
                           link_state->speed, link_state->fd ? "full" : "half",
                           efx->net_dev->mtu,
                           (efx->promiscuous ? " [PROMISC]" : ""));
        } else {
                netif_info(efx, link, efx->net_dev, "link down\n");
        }

}

void efx_link_set_advertising(struct efx_nic *efx, u32 advertising)
{
        efx->link_advertising = advertising;
        if (advertising) {
                if (advertising & ADVERTISED_Pause)
                        efx->wanted_fc |= (EFX_FC_TX | EFX_FC_RX);
                else
                        efx->wanted_fc &= ~(EFX_FC_TX | EFX_FC_RX);
                if (advertising & ADVERTISED_Asym_Pause)
                        efx->wanted_fc ^= EFX_FC_TX;
        }
}

void efx_link_set_wanted_fc(struct efx_nic *efx, u8 wanted_fc)
{
        efx->wanted_fc = wanted_fc;
        if (efx->link_advertising) {
                if (wanted_fc & EFX_FC_RX)
                        efx->link_advertising |= (ADVERTISED_Pause |
                                                  ADVERTISED_Asym_Pause);
                else
                        efx->link_advertising &= ~(ADVERTISED_Pause |
                                                   ADVERTISED_Asym_Pause);
                if (wanted_fc & EFX_FC_TX)
                        efx->link_advertising ^= ADVERTISED_Asym_Pause;
        }
}

static void efx_fini_port(struct efx_nic *efx);

/* 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_settings(), and pushed asynchronously to the MAC
 * through efx_monitor().
 *
 * Callers must hold the mac_lock
 */
int __efx_reconfigure_port(struct efx_nic *efx)
{
        enum efx_phy_mode phy_mode;
        int rc;

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

        /* Serialise the promiscuous flag with efx_set_multicast_list. */
        if (efx_dev_registered(efx)) {
                netif_addr_lock_bh(efx->net_dev);
                netif_addr_unlock_bh(efx->net_dev);
        }

        /* 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 efx_reconfigure_port(struct efx_nic *efx)
{
        int rc;

        EFX_ASSERT_RESET_SERIALISED(efx);

        mutex_lock(&efx->mac_lock);
        rc = __efx_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 efx_mac_work(struct work_struct *data)
{
        struct efx_nic *efx = container_of(data, struct efx_nic, mac_work);

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

static int efx_probe_port(struct efx_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 */
        memcpy(efx->net_dev->dev_addr, efx->net_dev->perm_addr, ETH_ALEN);

        return 0;
}

static int efx_init_port(struct efx_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) */
        efx->type->reconfigure_mac(efx);

        /* Ensure the PHY advertises the correct flow control settings */
        rc = efx->phy_op->reconfigure(efx);
        if (rc)
                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 efx_start_port(struct efx_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;

        /* efx_mac_work() might have been scheduled after efx_stop_port(),
         * and then cancelled by efx_flush_all() */
        efx->type->reconfigure_mac(efx);

        mutex_unlock(&efx->mac_lock);
}

/* Prevent efx_mac_work() and efx_monitor() from working */
static void efx_stop_port(struct efx_nic *efx)
{
        netif_dbg(efx, ifdown, efx->net_dev, "stop port\n");

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

        /* Serialise against efx_set_multicast_list() */
        if (efx_dev_registered(efx)) {
                netif_addr_lock_bh(efx->net_dev);
                netif_addr_unlock_bh(efx->net_dev);
        }
}

static void efx_fini_port(struct efx_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;
        efx_link_status_changed(efx);
}

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

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

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

/* This configures the PCI device to enable I/O and DMA. */
static int efx_init_io(struct efx_nic *efx)
{
        struct pci_dev *pci_dev = efx->pci_dev;
        dma_addr_t dma_mask = efx->type->max_dma_mask;
        int rc;

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

        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) {
                if (pci_dma_supported(pci_dev, dma_mask)) {
                        rc = pci_set_dma_mask(pci_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);
        rc = pci_set_consistent_dma_mask(pci_dev, dma_mask);
        if (rc) {
                /* pci_set_consistent_dma_mask() is not *allowed* to
                 * fail with a mask that pci_set_dma_mask() accepted,
                 * but just in case...
                 */
                netif_err(efx, probe, efx->net_dev,
                          "failed to set consistent DMA mask\n");
                goto fail2;
        }

        efx->membase_phys = pci_resource_start(efx->pci_dev, EFX_MEM_BAR);
        rc = pci_request_region(pci_dev, EFX_MEM_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,
                                       efx->type->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,
                          efx->type->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,
                  efx->type->mem_map_size, efx->membase);

        return 0;

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

static void efx_fini_io(struct efx_nic *efx)
{
        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) {
                pci_release_region(efx->pci_dev, EFX_MEM_BAR);
                efx->membase_phys = 0;
        }

        pci_disable_device(efx->pci_dev);
}

static int efx_wanted_parallelism(void)
{
        cpumask_var_t thread_mask;
        int count;
        int cpu;

        if (rss_cpus)
                return rss_cpus;

        if (unlikely(!zalloc_cpumask_var(&thread_mask, GFP_KERNEL))) {
                printk(KERN_WARNING
                       "sfc: 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_thread_cpumask(cpu));
                }
        }

        free_cpumask_var(thread_mask);
        return count;
}

static int
efx_init_rx_cpu_rmap(struct efx_nic *efx, struct msix_entry *xentries)
{
#ifdef CONFIG_RFS_ACCEL
        int i, rc;

        efx->net_dev->rx_cpu_rmap = alloc_irq_cpu_rmap(efx->n_rx_channels);
        if (!efx->net_dev->rx_cpu_rmap)
                return -ENOMEM;
        for (i = 0; i < efx->n_rx_channels; i++) {
                rc = irq_cpu_rmap_add(efx->net_dev->rx_cpu_rmap,
                                      xentries[i].vector);
                if (rc) {
                        free_irq_cpu_rmap(efx->net_dev->rx_cpu_rmap);
                        efx->net_dev->rx_cpu_rmap = NULL;
                        return rc;
                }
        }
#endif
        return 0;
}

/* Probe the number and type of interrupts we are able to obtain, and
 * the resulting numbers of channels and RX queues.
 */
static int efx_probe_interrupts(struct efx_nic *efx)
{
        int max_channels =
                min_t(int, efx->type->phys_addr_channels, EFX_MAX_CHANNELS);
        int rc, i;

        if (efx->interrupt_mode == EFX_INT_MODE_MSIX) {
                struct msix_entry xentries[EFX_MAX_CHANNELS];
                int n_channels;

                n_channels = efx_wanted_parallelism();
                if (separate_tx_channels)
                        n_channels *= 2;
                n_channels = min(n_channels, max_channels);

                for (i = 0; i < n_channels; i++)
                        xentries[i].entry = i;
                rc = pci_enable_msix(efx->pci_dev, xentries, n_channels);
                if (rc > 0) {
                        netif_err(efx, drv, efx->net_dev,
                                  "WARNING: Insufficient MSI-X vectors"
                                  " available (%d < %d).\n", rc, n_channels);
                        netif_err(efx, drv, efx->net_dev,
                                  "WARNING: Performance may be reduced.\n");
                        EFX_BUG_ON_PARANOID(rc >= n_channels);
                        n_channels = rc;
                        rc = pci_enable_msix(efx->pci_dev, xentries,
                                             n_channels);
                }

                if (rc == 0) {
                        efx->n_channels = n_channels;
                        if (separate_tx_channels) {
                                efx->n_tx_channels =
                                        max(efx->n_channels / 2, 1U);
                                efx->n_rx_channels =
                                        max(efx->n_channels -
                                            efx->n_tx_channels, 1U);
                        } else {
                                efx->n_tx_channels = efx->n_channels;
                                efx->n_rx_channels = efx->n_channels;
                        }
                        rc = efx_init_rx_cpu_rmap(efx, xentries);
                        if (rc) {
                                pci_disable_msix(efx->pci_dev);
                                return rc;
                        }
                        for (i = 0; i < n_channels; i++)
                                efx_get_channel(efx, i)->irq =
                                        xentries[i].vector;
                } else {
                        /* Fall back to single channel MSI */
                        efx->interrupt_mode = EFX_INT_MODE_MSI;
                        netif_err(efx, drv, efx->net_dev,
                                  "could not enable MSI-X\n");
                }
        }

        /* Try single interrupt MSI */
        if (efx->interrupt_mode == EFX_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) {
                        efx_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 = EFX_INT_MODE_LEGACY;
                }
        }

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

        return 0;
}

static void efx_remove_interrupts(struct efx_nic *efx)
{
        struct efx_channel *channel;

        /* Remove MSI/MSI-X interrupts */
        efx_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 efx_set_channels(struct efx_nic *efx)
{
        struct efx_channel *channel;
        struct efx_tx_queue *tx_queue;

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

        /* We need to adjust the TX queue numbers if we have separate
         * RX-only and TX-only channels.
         */
        efx_for_each_channel(channel, efx) {
                efx_for_each_channel_tx_queue(tx_queue, channel)
                        tx_queue->queue -= (efx->tx_channel_offset *
                                            EFX_TXQ_TYPES);
        }
}

static int efx_probe_nic(struct efx_nic *efx)
{
        size_t i;
        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;

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

        if (efx->n_channels > 1)
                get_random_bytes(&efx->rx_hash_key, sizeof(efx->rx_hash_key));
        for (i = 0; i < ARRAY_SIZE(efx->rx_indir_table); i++)
                efx->rx_indir_table[i] =
                        ethtool_rxfh_indir_default(i, efx->n_rx_channels);

        efx_set_channels(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_init_irq_moderation(efx, tx_irq_mod_usec, rx_irq_mod_usec, true,
                                true);

        return 0;

fail:
        efx->type->remove(efx);
        return rc;
}

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

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

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

static int efx_probe_all(struct efx_nic *efx)
{
        int rc;

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

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

        efx->rxq_entries = efx->txq_entries = EFX_DEFAULT_DMAQ_SIZE;
        rc = efx_probe_channels(efx);
        if (rc)
                goto fail3;

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

        return 0;

 fail4:
        efx_remove_channels(efx);
 fail3:
        efx_remove_port(efx);
 fail2:
        efx_remove_nic(efx);
 fail1:
        return rc;
}

/* Called after previous invocation(s) of efx_stop_all, restarts the
 * port, kernel transmit queue, NAPI processing and hardware interrupts,
 * and ensures that the port is scheduled to be reconfigured.
 * This function is safe to call multiple times when the NIC is in any
 * state. */
static void efx_start_all(struct efx_nic *efx)
{
        struct efx_channel *channel;

        EFX_ASSERT_RESET_SERIALISED(efx);

        /* 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)
                return;
        if ((efx->state != STATE_RUNNING) && (efx->state != STATE_INIT))
                return;
        if (efx_dev_registered(efx) && !netif_running(efx->net_dev))
                return;

        /* Mark the port as enabled so port reconfigurations can start, then
         * restart the transmit interface early so the watchdog timer stops */
        efx_start_port(efx);

        if (efx_dev_registered(efx) && netif_device_present(efx->net_dev))
                netif_tx_wake_all_queues(efx->net_dev);

        efx_for_each_channel(channel, efx)
                efx_start_channel(channel);

        if (efx->legacy_irq)
                efx->legacy_irq_enabled = true;
        efx_nic_enable_interrupts(efx);

        /* Switch to event based MCDI completions after enabling interrupts.
         * If a reset has been scheduled, then we need to stay in polled mode.
         * Rather than serialising efx_mcdi_mode_event() [which sleeps] and
         * reset_pending [modified from an atomic context], we instead guarantee
         * that efx_mcdi_mode_poll() isn't reverted erroneously */
        efx_mcdi_mode_event(efx);
        if (efx->reset_pending)
                efx_mcdi_mode_poll(efx);

        /* Start the hardware monitor if there is one. Otherwise (we're link
         * event driven), we have to poll the PHY because after an event queue
         * flush, we could have a missed a link state change */
        if (efx->type->monitor != NULL) {
                queue_delayed_work(efx->workqueue, &efx->monitor_work,
                                   efx_monitor_interval);
        } else {
                mutex_lock(&efx->mac_lock);
                if (efx->phy_op->poll(efx))
                        efx_link_status_changed(efx);
                mutex_unlock(&efx->mac_lock);
        }

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

/* Flush all delayed work. Should only be called when no more delayed work
 * will be scheduled. This doesn't flush pending online resets (efx_reset),
 * since we're holding the rtnl_lock at this point. */
static void efx_flush_all(struct efx_nic *efx)
{
        /* Make sure the hardware monitor is stopped */
        cancel_delayed_work_sync(&efx->monitor_work);
        /* Stop scheduled port reconfigurations */
        cancel_work_sync(&efx->mac_work);
}

/* Quiesce hardware and software without bringing the link down.
 * Safe to call multiple times, when the nic and interface is in any
 * state. The caller is guaranteed to subsequently be in a position
 * to modify any hardware and software state they see fit without
 * taking locks. */
static void efx_stop_all(struct efx_nic *efx)
{
        struct efx_channel *channel;

        EFX_ASSERT_RESET_SERIALISED(efx);

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

        efx->type->stop_stats(efx);

        /* Switch to MCDI polling on Siena before disabling interrupts */
        efx_mcdi_mode_poll(efx);

        /* Disable interrupts and wait for ISR to complete */
        efx_nic_disable_interrupts(efx);
        if (efx->legacy_irq) {
                synchronize_irq(efx->legacy_irq);
                efx->legacy_irq_enabled = false;
        }
        efx_for_each_channel(channel, efx) {
                if (channel->irq)
                        synchronize_irq(channel->irq);
        }

        /* Stop all NAPI processing and synchronous rx refills */
        efx_for_each_channel(channel, efx)
                efx_stop_channel(channel);

        /* Stop all asynchronous port reconfigurations. Since all
         * event processing has already been stopped, there is no
         * window to loose phy events */
        efx_stop_port(efx);

        /* Flush efx_mac_work(), refill_workqueue, monitor_work */
        efx_flush_all(efx);

        /* Stop the kernel transmit interface late, so the watchdog
         * timer isn't ticking over the flush */
        if (efx_dev_registered(efx)) {
                netif_tx_stop_all_queues(efx->net_dev);
                netif_tx_lock_bh(efx->net_dev);
                netif_tx_unlock_bh(efx->net_dev);
        }
}

static void efx_remove_all(struct efx_nic *efx)
{
        efx_remove_filters(efx);
        efx_remove_channels(efx);
        efx_remove_port(efx);
        efx_remove_nic(efx);
}

/**************************************************************************
 *
 * Interrupt moderation
 *
 **************************************************************************/

static unsigned int irq_mod_ticks(unsigned int usecs, unsigned int quantum_ns)
{
        if (usecs == 0)
                return 0;
        if (usecs * 1000 < quantum_ns)
                return 1; /* never round down to 0 */
        return usecs * 1000 / quantum_ns;
}

/* Set interrupt moderation parameters */
int efx_init_irq_moderation(struct efx_nic *efx, unsigned int tx_usecs,
                            unsigned int rx_usecs, bool rx_adaptive,
                            bool rx_may_override_tx)
{
        struct efx_channel *channel;
        unsigned int irq_mod_max = DIV_ROUND_UP(efx->type->timer_period_max *
                                                efx->timer_quantum_ns,
                                                1000);
        unsigned int tx_ticks;
        unsigned int rx_ticks;

        EFX_ASSERT_RESET_SERIALISED(efx);

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

        tx_ticks = irq_mod_ticks(tx_usecs, efx->timer_quantum_ns);
        rx_ticks = irq_mod_ticks(rx_usecs, efx->timer_quantum_ns);

        if (tx_ticks != rx_ticks && 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 = rx_ticks;
        efx_for_each_channel(channel, efx) {
                if (efx_channel_has_rx_queue(channel))
                        channel->irq_moderation = rx_ticks;
                else if (efx_channel_has_tx_queues(channel))
                        channel->irq_moderation = tx_ticks;
        }

        return 0;
}

void efx_get_irq_moderation(struct efx_nic *efx, unsigned int *tx_usecs,
                            unsigned int *rx_usecs, bool *rx_adaptive)
{
        /* We must round up when converting ticks to microseconds
         * because we round down when converting the other way.
         */

        *rx_adaptive = efx->irq_rx_adaptive;
        *rx_usecs = DIV_ROUND_UP(efx->irq_rx_moderation *
                                 efx->timer_quantum_ns,
                                 1000);

        /* 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
                *tx_usecs = DIV_ROUND_UP(
                        efx->channel[efx->tx_channel_offset]->irq_moderation *
                        efx->timer_quantum_ns,
                        1000);
}

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

/* Run periodically off the general workqueue */
static void efx_monitor(struct work_struct *data)
{
        struct efx_nic *efx = container_of(data, struct efx_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,
                           efx_monitor_interval);
}

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

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

        EFX_ASSERT_RESET_SERIALISED(efx);

        /* 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 efx_init_napi(struct efx_nic *efx)
{
        struct efx_channel *channel;

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

static void efx_fini_napi_channel(struct efx_channel *channel)
{
        if (channel->napi_dev)
                netif_napi_del(&channel->napi_str);
        channel->napi_dev = NULL;
}

static void efx_fini_napi(struct efx_nic *efx)
{
        struct efx_channel *channel;

        efx_for_each_channel(channel, efx)
                efx_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 efx_netpoll(struct net_device *net_dev)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        struct efx_channel *channel;

        efx_for_each_channel(channel, efx)
                efx_schedule_channel(channel);
}

#endif

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

/* Context: process, rtnl_lock() held. */
static int efx_net_open(struct net_device *net_dev)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        EFX_ASSERT_RESET_SERIALISED(efx);

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

        if (efx->state == STATE_DISABLED)
                return -EIO;
        if (efx->phy_mode & PHY_MODE_SPECIAL)
                return -EBUSY;
        if (efx_mcdi_poll_reboot(efx) && efx_reset(efx, RESET_TYPE_ALL))
                return -EIO;

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

        efx_start_all(efx);
        return 0;
}

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

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

        if (efx->state != STATE_DISABLED) {
                /* Stop the device and flush all the channels */
                efx_stop_all(efx);
                efx_fini_channels(efx);
                efx_init_channels(efx);
        }

        return 0;
}

/* Context: process, dev_base_lock or RTNL held, non-blocking. */
static struct rtnl_link_stats64 *efx_net_stats(struct net_device *net_dev, struct rtnl_link_stats64 *stats)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        struct efx_mac_stats *mac_stats = &efx->mac_stats;

        spin_lock_bh(&efx->stats_lock);

        efx->type->update_stats(efx);

        stats->rx_packets = mac_stats->rx_packets;
        stats->tx_packets = mac_stats->tx_packets;
        stats->rx_bytes = mac_stats->rx_bytes;
        stats->tx_bytes = mac_stats->tx_bytes;
        stats->rx_dropped = efx->n_rx_nodesc_drop_cnt;
        stats->multicast = mac_stats->rx_multicast;
        stats->collisions = mac_stats->tx_collision;
        stats->rx_length_errors = (mac_stats->rx_gtjumbo +
                                   mac_stats->rx_length_error);
        stats->rx_crc_errors = mac_stats->rx_bad;
        stats->rx_frame_errors = mac_stats->rx_align_error;
        stats->rx_fifo_errors = mac_stats->rx_overflow;
        stats->rx_missed_errors = mac_stats->rx_missed;
        stats->tx_window_errors = mac_stats->tx_late_collision;

        stats->rx_errors = (stats->rx_length_errors +
                            stats->rx_crc_errors +
                            stats->rx_frame_errors +
                            mac_stats->rx_symbol_error);
        stats->tx_errors = (stats->tx_window_errors +
                            mac_stats->tx_bad);

        spin_unlock_bh(&efx->stats_lock);

        return stats;
}

/* Context: netif_tx_lock held, BHs disabled. */
static void efx_watchdog(struct net_device *net_dev)
{
        struct efx_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);

        efx_schedule_reset(efx, RESET_TYPE_TX_WATCHDOG);
}


/* Context: process, rtnl_lock() held. */
static int efx_change_mtu(struct net_device *net_dev, int new_mtu)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        int rc = 0;

        EFX_ASSERT_RESET_SERIALISED(efx);

        if (new_mtu > EFX_MAX_MTU)
                return -EINVAL;

        efx_stop_all(efx);

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

        efx_fini_channels(efx);

        mutex_lock(&efx->mac_lock);
        /* Reconfigure the MAC before enabling the dma queues so that
         * the RX buffers don't overflow */
        net_dev->mtu = new_mtu;
        efx->type->reconfigure_mac(efx);
        mutex_unlock(&efx->mac_lock);

        efx_init_channels(efx);

        efx_start_all(efx);
        return rc;
}

static int efx_set_mac_address(struct net_device *net_dev, void *data)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        struct sockaddr *addr = data;
        char *new_addr = addr->sa_data;

        EFX_ASSERT_RESET_SERIALISED(efx);

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

        memcpy(net_dev->dev_addr, new_addr, net_dev->addr_len);

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

        return 0;
}

/* Context: netif_addr_lock held, BHs disabled. */
static void efx_set_multicast_list(struct net_device *net_dev)
{
        struct efx_nic *efx = netdev_priv(net_dev);
        struct netdev_hw_addr *ha;
        union efx_multicast_hash *mc_hash = &efx->multicast_hash;
        u32 crc;
        int bit;

        efx->promiscuous = !!(net_dev->flags & IFF_PROMISC);

        /* Build multicast hash table */
        if (efx->promiscuous || (net_dev->flags & IFF_ALLMULTI)) {
                memset(mc_hash, 0xff, sizeof(*mc_hash));
        } else {
                memset(mc_hash, 0x00, sizeof(*mc_hash));
                netdev_for_each_mc_addr(ha, net_dev) {
                        crc = ether_crc_le(ETH_ALEN, ha->addr);
                        bit = crc & (EFX_MCAST_HASH_ENTRIES - 1);
                        set_bit_le(bit, mc_hash->byte);
                }

                /* Broadcast packets go through the multicast hash filter.
                 * ether_crc_le() of the broadcast address is 0xbe2612ff
                 * so we always add bit 0xff to the mask.
                 */
                set_bit_le(0xff, mc_hash->byte);
        }

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

static int efx_set_features(struct net_device *net_dev, netdev_features_t data)
{
        struct efx_nic *efx = netdev_priv(net_dev);

        /* If disabling RX n-tuple filtering, clear existing filters */
        if (net_dev->features & ~data & NETIF_F_NTUPLE)
                efx_filter_clear_rx(efx, EFX_FILTER_PRI_MANUAL);

        return 0;
}

static const struct net_device_ops efx_netdev_ops = {
        .ndo_open               = efx_net_open,
        .ndo_stop               = efx_net_stop,
        .ndo_get_stats64        = efx_net_stats,
        .ndo_tx_timeout         = efx_watchdog,
        .ndo_start_xmit         = efx_hard_start_xmit,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_do_ioctl           = efx_ioctl,
        .ndo_change_mtu         = efx_change_mtu,
        .ndo_set_mac_address    = efx_set_mac_address,
        .ndo_set_rx_mode        = efx_set_multicast_list,
        .ndo_set_features       = efx_set_features,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = efx_netpoll,
#endif
        .ndo_setup_tc           = efx_setup_tc,
#ifdef CONFIG_RFS_ACCEL
        .ndo_rx_flow_steer      = efx_filter_rfs,
#endif
};

static void efx_update_name(struct efx_nic *efx)
{
        strcpy(efx->name, efx->net_dev->name);
        efx_mtd_rename(efx);
        efx_set_channel_names(efx);
}

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

        if (net_dev->netdev_ops == &efx_netdev_ops &&
            event == NETDEV_CHANGENAME)
                efx_update_name(netdev_priv(net_dev));

        return NOTIFY_DONE;
}

static struct notifier_block efx_netdev_notifier = {
        .notifier_call = efx_netdev_event,
};

static ssize_t
show_phy_type(struct device *dev, struct device_attribute *attr, char *buf)
{
        struct efx_nic *efx = pci_get_drvdata(to_pci_dev(dev));
        return sprintf(buf, "%d\n", efx->phy_type);
}
static DEVICE_ATTR(phy_type, 0644, show_phy_type, NULL);

static int efx_register_netdev(struct efx_nic *efx)
{
        struct net_device *net_dev = efx->net_dev;
        struct efx_channel *channel;
        int rc;

        net_dev->watchdog_timeo = 5 * HZ;
        net_dev->irq = efx->pci_dev->irq;
        net_dev->netdev_ops = &efx_netdev_ops;
        SET_ETHTOOL_OPS(net_dev, &efx_ethtool_ops);

        rtnl_lock();

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

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

        efx_for_each_channel(channel, efx) {
                struct efx_tx_queue *tx_queue;
                efx_for_each_channel_tx_queue(tx_queue, channel)
                        efx_init_tx_queue_core_txq(tx_queue);
        }

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

        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_locked:
        rtnl_unlock();
        netif_err(efx, drv, efx->net_dev, "could not register net dev\n");
        return rc;

fail_registered:
        unregister_netdev(net_dev);
        return rc;
}

static void efx_unregister_netdev(struct efx_nic *efx)
{
        struct efx_channel *channel;
        struct efx_tx_queue *tx_queue;

        if (!efx->net_dev)
                return;

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

        /* Free up any skbs still remaining. This has to happen before
         * we try to unregister the netdev as running their destructors
         * may be needed to get the device ref. count to 0. */
        efx_for_each_channel(channel, efx) {
                efx_for_each_channel_tx_queue(tx_queue, channel)
                        efx_release_tx_buffers(tx_queue);
        }

        if (efx_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 efx_reset_down(struct efx_nic *efx, enum reset_type method)
{
        EFX_ASSERT_RESET_SERIALISED(efx);

        efx_stop_all(efx);
        mutex_lock(&efx->mac_lock);

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

/* This function will always ensure that the locks acquired in
 * efx_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 efx_reset_up(struct efx_nic *efx, enum reset_type method, bool ok)
{
        int rc;

        EFX_ASSERT_RESET_SERIALISED(efx);

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

        efx->type->reconfigure_mac(efx);

        efx_init_channels(efx);
        efx_restore_filters(efx);

        mutex_unlock(&efx->mac_lock);

        efx_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 efx_reset(struct efx_nic *efx, enum reset_type method)
{
        int rc, rc2;
        bool disabled;

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

        netif_device_detach(efx->net_dev);
        efx_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.
         */
        efx->reset_pending &= -(1 << (method + 1));

        /* 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;
        rc2 = efx_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;
}

/* The worker thread exists so that code that cannot sleep can
 * schedule a reset for later.
 */
static void efx_reset_work(struct work_struct *data)
{
        struct efx_nic *efx = container_of(data, struct efx_nic, reset_work);
        unsigned long pending = ACCESS_ONCE(efx->reset_pending);

        if (!pending)
                return;

        /* If we're not RUNNING then don't reset. Leave the reset_pending
         * flags set so that efx_pci_probe_main will be retried */
        if (efx->state != STATE_RUNNING) {
                netif_info(efx, drv, efx->net_dev,
                           "scheduled reset quenched. NIC not RUNNING\n");
                return;
        }

        rtnl_lock();
        (void)efx_reset(efx, fls(pending) - 1);
        rtnl_unlock();
}

void efx_schedule_reset(struct efx_nic *efx, enum reset_type type)
{
        enum reset_type method;

        switch (type) {
        case RESET_TYPE_INVISIBLE:
        case RESET_TYPE_ALL:
        case RESET_TYPE_WORLD:
        case RESET_TYPE_DISABLE:
                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);

        /* efx_process_channel() will no longer read events once a
         * reset is scheduled. So switch back to poll'd MCDI completions. */
        efx_mcdi_mode_poll(efx);

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

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

/* PCI device ID table */
static DEFINE_PCI_DEVICE_TABLE(efx_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},
        {PCI_DEVICE(PCI_VENDOR_ID_SOLARFLARE, 0x0803),  /* SFC9020 */
         .driver_data = (unsigned long) &siena_a0_nic_type},
        {PCI_DEVICE(PCI_VENDOR_ID_SOLARFLARE, 0x0813),  /* SFL9021 */
         .driver_data = (unsigned long) &siena_a0_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 efx_port_dummy_op_int(struct efx_nic *efx)
{
        return 0;
}
void efx_port_dummy_op_void(struct efx_nic *efx) {}

static bool efx_port_dummy_op_poll(struct efx_nic *efx)
{
        return false;
}

static const struct efx_phy_operations efx_dummy_phy_operations = {
        .init            = efx_port_dummy_op_int,
        .reconfigure     = efx_port_dummy_op_int,
        .poll            = efx_port_dummy_op_poll,
        .fini            = efx_port_dummy_op_void,
};

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

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

        /* Initialise common structures */
        memset(efx, 0, sizeof(*efx));
        spin_lock_init(&efx->biu_lock);
#ifdef CONFIG_SFC_MTD
        INIT_LIST_HEAD(&efx->mtd_list);
#endif
        INIT_WORK(&efx->reset_work, efx_reset_work);
        INIT_DELAYED_WORK(&efx->monitor_work, efx_monitor);
        efx->pci_dev = pci_dev;
        efx->msg_enable = debug;
        efx->state = STATE_INIT;
        strlcpy(efx->name, pci_name(pci_dev), sizeof(efx->name));

        efx->net_dev = net_dev;
        spin_lock_init(&efx->stats_lock);
        mutex_init(&efx->mac_lock);
        efx->phy_op = &efx_dummy_phy_operations;
        efx->mdio.dev = net_dev;
        INIT_WORK(&efx->mac_work, efx_mac_work);

        for (i = 0; i < EFX_MAX_CHANNELS; i++) {
                efx->channel[i] = efx_alloc_channel(efx, i, NULL);
                if (!efx->channel[i])
                        goto fail;
        }

        efx->type = type;

        EFX_BUG_ON_PARANOID(efx->type->phys_addr_channels > EFX_MAX_CHANNELS);

        /* 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:
        efx_fini_struct(efx);
        return -ENOMEM;
}

static void efx_fini_struct(struct efx_nic *efx)
{
        int i;

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

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

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

/* Main body of final NIC shutdown code
 * This is called only at module unload (or hotplug removal).
 */
static void efx_pci_remove_main(struct efx_nic *efx)
{
#ifdef CONFIG_RFS_ACCEL
        free_irq_cpu_rmap(efx->net_dev->rx_cpu_rmap);
        efx->net_dev->rx_cpu_rmap = NULL;
#endif
        efx_nic_fini_interrupt(efx);
        efx_fini_channels(efx);
        efx_fini_port(efx);
        efx->type->fini(efx);
        efx_fini_napi(efx);
        efx_remove_all(efx);
}

/* Final NIC shutdown
 * This is called only at module unload (or hotplug removal).
 */
static void efx_pci_remove(struct pci_dev *pci_dev)
{
        struct efx_nic *efx;

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

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

        /* Allow any queued efx_resets() to complete */
        rtnl_unlock();

        efx_unregister_netdev(efx);

        efx_mtd_remove(efx);

        /* Wait for any scheduled resets to complete. No more will be
         * scheduled from this point because efx_stop_all() has been
         * called, we are no longer registered with driverlink, and
         * the net_device's have been removed. */
        cancel_work_sync(&efx->reset_work);

        efx_pci_remove_main(efx);

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

        pci_set_drvdata(pci_dev, NULL);
        efx_fini_struct(efx);
        free_netdev(efx->net_dev);
};

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

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

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

        efx_init_channels(efx);

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

        return 0;

 fail5:
        efx_fini_channels(efx);
        efx_fini_port(efx);
 fail4:
        efx->type->fini(efx);
 fail3:
        efx_fini_napi(efx);
        efx_remove_all(efx);
 fail1:
        return rc;
}

/* NIC initialisation
 *
 * This is called at module load (or hotplug insertion,
 * theoretically).  It sets up PCI mappings, tests and 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. efx_net_open).
 */
static int __devinit efx_pci_probe(struct pci_dev *pci_dev,
                                   const struct pci_device_id *entry)
{
        const struct efx_nic_type *type = (const struct efx_nic_type *) entry->driver_data;
        struct net_device *net_dev;
        struct efx_nic *efx;
        int i, rc;

        /* Allocate and initialise a struct net_device and struct efx_nic */
        net_dev = alloc_etherdev_mqs(sizeof(*efx), EFX_MAX_CORE_TX_QUEUES,
                                     EFX_MAX_RX_QUEUES);
        if (!net_dev)
                return -ENOMEM;
        net_dev->features |= (type->offload_features | NETIF_F_SG |
                              NETIF_F_HIGHDMA | NETIF_F_TSO |
                              NETIF_F_RXCSUM);
        if (type->offload_features & NETIF_F_V6_CSUM)
                net_dev->features |= NETIF_F_TSO6;
        /* Mask for features that also apply to VLAN devices */
        net_dev->vlan_features |= (NETIF_F_ALL_CSUM | NETIF_F_SG |
                                   NETIF_F_HIGHDMA | NETIF_F_ALL_TSO |
                                   NETIF_F_RXCSUM);
        /* All offloads can be toggled */
        net_dev->hw_features = net_dev->features & ~NETIF_F_HIGHDMA;
        efx = netdev_priv(net_dev);
        pci_set_drvdata(pci_dev, efx);
        SET_NETDEV_DEV(net_dev, &pci_dev->dev);
        rc = efx_init_struct(efx, type, pci_dev, net_dev);
        if (rc)
                goto fail1;

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

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

        /* No serialisation is required with the reset path because
         * we're in STATE_INIT. */
        for (i = 0; i < 5; i++) {
                rc = efx_pci_probe_main(efx);

                /* Serialise against efx_reset(). No more resets will be
                 * scheduled since efx_stop_all() has been called, and we
                 * have not and never have been registered with either
                 * the rtnetlink or driverlink layers. */
                cancel_work_sync(&efx->reset_work);

                if (rc == 0) {
                        if (efx->reset_pending) {
                                /* If there was a scheduled reset during
                                 * probe, the NIC is probably hosed anyway */
                                efx_pci_remove_main(efx);
                                rc = -EIO;
                        } else {
                                break;
                        }
                }

                /* Retry if a recoverably reset event has been scheduled */
                if (efx->reset_pending &
                    ~(1 << RESET_TYPE_INVISIBLE | 1 << RESET_TYPE_ALL) ||
                    !efx->reset_pending)
                        goto fail3;

                efx->reset_pending = 0;
        }

        if (rc) {
                netif_err(efx, probe, efx->net_dev, "Could not reset NIC\n");
                goto fail4;
        }

        /* Switch to the running state before we expose the device to the OS,
         * so that dev_open()|efx_start_all() will actually start the device */
        efx->state = STATE_RUNNING;

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

        netif_dbg(efx, probe, efx->net_dev, "initialisation successful\n");

        rtnl_lock();
        efx_mtd_probe(efx); /* allowed to fail */
        rtnl_unlock();
        return 0;

 fail5:
        efx_pci_remove_main(efx);
 fail4:
 fail3:
        efx_fini_io(efx);
 fail2:
        efx_fini_struct(efx);
 fail1:
        WARN_ON(rc > 0);
        netif_dbg(efx, drv, efx->net_dev, "initialisation failed. rc=%d\n", rc);
        free_netdev(net_dev);
        return rc;
}

static int efx_pm_freeze(struct device *dev)
{
        struct efx_nic *efx = pci_get_drvdata(to_pci_dev(dev));

        efx->state = STATE_FINI;

        netif_device_detach(efx->net_dev);

        efx_stop_all(efx);
        efx_fini_channels(efx);

        return 0;
}

static int efx_pm_thaw(struct device *dev)
{
        struct efx_nic *efx = pci_get_drvdata(to_pci_dev(dev));

        efx->state = STATE_INIT;

        efx_init_channels(efx);

        mutex_lock(&efx->mac_lock);
        efx->phy_op->reconfigure(efx);
        mutex_unlock(&efx->mac_lock);

        efx_start_all(efx);

        netif_device_attach(efx->net_dev);

        efx->state = STATE_RUNNING;

        efx->type->resume_wol(efx);

        /* Reschedule any quenched resets scheduled during efx_pm_freeze() */
        queue_work(reset_workqueue, &efx->reset_work);

        return 0;
}

static int efx_pm_poweroff(struct device *dev)
{
        struct pci_dev *pci_dev = to_pci_dev(dev);
        struct efx_nic *efx = pci_get_drvdata(pci_dev);

        efx->type->fini(efx);

        efx->reset_pending = 0;

        pci_save_state(pci_dev);
        return pci_set_power_state(pci_dev, PCI_D3hot);
}

/* Used for both resume and restore */
static int efx_pm_resume(struct device *dev)
{
        struct pci_dev *pci_dev = to_pci_dev(dev);
        struct efx_nic *efx = pci_get_drvdata(pci_dev);
        int rc;

        rc = pci_set_power_state(pci_dev, PCI_D0);
        if (rc)
                return rc;
        pci_restore_state(pci_dev);
        rc = pci_enable_device(pci_dev);
        if (rc)
                return rc;
        pci_set_master(efx->pci_dev);
        rc = efx->type->reset(efx, RESET_TYPE_ALL);
        if (rc)
                return rc;
        rc = efx->type->init(efx);
        if (rc)
                return rc;
        efx_pm_thaw(dev);
        return 0;
}

static int efx_pm_suspend(struct device *dev)
{
        int rc;

        efx_pm_freeze(dev);
        rc = efx_pm_poweroff(dev);
        if (rc)
                efx_pm_resume(dev);
        return rc;
}

static const struct dev_pm_ops efx_pm_ops = {
        .suspend        = efx_pm_suspend,
        .resume         = efx_pm_resume,
        .freeze         = efx_pm_freeze,
        .thaw           = efx_pm_thaw,
        .poweroff       = efx_pm_poweroff,
        .restore        = efx_pm_resume,
};

static struct pci_driver efx_pci_driver = {
        .name           = KBUILD_MODNAME,
        .id_table       = efx_pci_table,
        .probe          = efx_pci_probe,
        .remove         = efx_pci_remove,
        .driver.pm      = &efx_pm_ops,
};

/**************************************************************************
 *
 * Kernel module interface
 *
 *************************************************************************/

module_param(interrupt_mode, uint, 0444);
MODULE_PARM_DESC(interrupt_mode,
                 "Interrupt mode (0=>MSIX 1=>MSI 2=>legacy)");

static int __init efx_init_module(void)
{
        int rc;

        printk(KERN_INFO "Solarflare NET driver v" EFX_DRIVER_VERSION "\n");

        rc = register_netdevice_notifier(&efx_netdev_notifier);
        if (rc)
                goto err_notifier;

        reset_workqueue = create_singlethread_workqueue("sfc_reset");
        if (!reset_workqueue) {
                rc = -ENOMEM;
                goto err_reset;
        }

        rc = pci_register_driver(&efx_pci_driver);
        if (rc < 0)
                goto err_pci;

        return 0;

 err_pci:
        destroy_workqueue(reset_workqueue);
 err_reset:
        unregister_netdevice_notifier(&efx_netdev_notifier);
 err_notifier:
        return rc;
}

static void __exit efx_exit_module(void)
{
        printk(KERN_INFO "Solarflare NET driver unloading\n");

        pci_unregister_driver(&efx_pci_driver);
        destroy_workqueue(reset_workqueue);
        unregister_netdevice_notifier(&efx_netdev_notifier);

}

module_init(efx_init_module);
module_exit(efx_exit_module);

MODULE_AUTHOR("Solarflare Communications and "
              "Michael Brown <mbrown@fensystems.co.uk>");
MODULE_DESCRIPTION("Solarflare Communications network driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, efx_pci_table);