// SPDX-License-Identifier: GPL-2.0
/* Copyright (c)  2018 Intel Corporation */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/if_vlan.h>
#include <linux/aer.h>

#include "igc.h"
#include "igc_hw.h"

#define DRV_VERSION     "0.0.1-k"
#define DRV_SUMMARY     "Intel(R) 2.5G Ethernet Linux Driver"

#define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)

static int debug = -1;

MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
MODULE_DESCRIPTION(DRV_SUMMARY);
MODULE_LICENSE("GPL v2");
MODULE_VERSION(DRV_VERSION);
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

char igc_driver_name[] = "igc";
char igc_driver_version[] = DRV_VERSION;
static const char igc_driver_string[] = DRV_SUMMARY;
static const char igc_copyright[] =
        "Copyright(c) 2018 Intel Corporation.";

static const struct igc_info *igc_info_tbl[] = {
        [board_base] = &igc_base_info,
};

static const struct pci_device_id igc_pci_tbl[] = {
        { PCI_VDEVICE(INTEL, IGC_DEV_ID_I225_LM), board_base },
        { PCI_VDEVICE(INTEL, IGC_DEV_ID_I225_V), board_base },
        /* required last entry */
        {0, }
};

MODULE_DEVICE_TABLE(pci, igc_pci_tbl);

/* forward declaration */
static void igc_clean_tx_ring(struct igc_ring *tx_ring);
static int igc_sw_init(struct igc_adapter *);
static void igc_configure(struct igc_adapter *adapter);
static void igc_power_down_link(struct igc_adapter *adapter);
static void igc_set_default_mac_filter(struct igc_adapter *adapter);
static void igc_set_rx_mode(struct net_device *netdev);
static void igc_write_itr(struct igc_q_vector *q_vector);
static void igc_assign_vector(struct igc_q_vector *q_vector, int msix_vector);
static void igc_free_q_vector(struct igc_adapter *adapter, int v_idx);
static void igc_set_interrupt_capability(struct igc_adapter *adapter,
                                         bool msix);
static void igc_free_q_vectors(struct igc_adapter *adapter);
static void igc_irq_disable(struct igc_adapter *adapter);
static void igc_irq_enable(struct igc_adapter *adapter);
static void igc_configure_msix(struct igc_adapter *adapter);
static bool igc_alloc_mapped_page(struct igc_ring *rx_ring,
                                  struct igc_rx_buffer *bi);

enum latency_range {
        lowest_latency = 0,
        low_latency = 1,
        bulk_latency = 2,
        latency_invalid = 255
};

void igc_reset(struct igc_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;
        struct igc_hw *hw = &adapter->hw;
        struct igc_fc_info *fc = &hw->fc;
        u32 pba, hwm;

        /* Repartition PBA for greater than 9k MTU if required */
        pba = IGC_PBA_34K;

        /* flow control settings
         * The high water mark must be low enough to fit one full frame
         * after transmitting the pause frame.  As such we must have enough
         * space to allow for us to complete our current transmit and then
         * receive the frame that is in progress from the link partner.
         * Set it to:
         * - the full Rx FIFO size minus one full Tx plus one full Rx frame
         */
        hwm = (pba << 10) - (adapter->max_frame_size + MAX_JUMBO_FRAME_SIZE);

        fc->high_water = hwm & 0xFFFFFFF0;      /* 16-byte granularity */
        fc->low_water = fc->high_water - 16;
        fc->pause_time = 0xFFFF;
        fc->send_xon = 1;
        fc->current_mode = fc->requested_mode;

        hw->mac.ops.reset_hw(hw);

        if (hw->mac.ops.init_hw(hw))
                dev_err(&pdev->dev, "Hardware Error\n");

        if (!netif_running(adapter->netdev))
                igc_power_down_link(adapter);

        igc_get_phy_info(hw);
}

/**
 * igc_power_up_link - Power up the phy/serdes link
 * @adapter: address of board private structure
 */
static void igc_power_up_link(struct igc_adapter *adapter)
{
        igc_reset_phy(&adapter->hw);

        if (adapter->hw.phy.media_type == igc_media_type_copper)
                igc_power_up_phy_copper(&adapter->hw);

        igc_setup_link(&adapter->hw);
}

/**
 * igc_power_down_link - Power down the phy/serdes link
 * @adapter: address of board private structure
 */
static void igc_power_down_link(struct igc_adapter *adapter)
{
        if (adapter->hw.phy.media_type == igc_media_type_copper)
                igc_power_down_phy_copper_base(&adapter->hw);
}

/**
 * igc_release_hw_control - release control of the h/w to f/w
 * @adapter: address of board private structure
 *
 * igc_release_hw_control resets CTRL_EXT:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that the
 * driver is no longer loaded.
 */
static void igc_release_hw_control(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        u32 ctrl_ext;

        /* Let firmware take over control of h/w */
        ctrl_ext = rd32(IGC_CTRL_EXT);
        wr32(IGC_CTRL_EXT,
             ctrl_ext & ~IGC_CTRL_EXT_DRV_LOAD);
}

/**
 * igc_get_hw_control - get control of the h/w from f/w
 * @adapter: address of board private structure
 *
 * igc_get_hw_control sets CTRL_EXT:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that
 * the driver is loaded.
 */
static void igc_get_hw_control(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        u32 ctrl_ext;

        /* Let firmware know the driver has taken over */
        ctrl_ext = rd32(IGC_CTRL_EXT);
        wr32(IGC_CTRL_EXT,
             ctrl_ext | IGC_CTRL_EXT_DRV_LOAD);
}

/**
 * igc_free_tx_resources - Free Tx Resources per Queue
 * @tx_ring: Tx descriptor ring for a specific queue
 *
 * Free all transmit software resources
 */
void igc_free_tx_resources(struct igc_ring *tx_ring)
{
        igc_clean_tx_ring(tx_ring);

        vfree(tx_ring->tx_buffer_info);
        tx_ring->tx_buffer_info = NULL;

        /* if not set, then don't free */
        if (!tx_ring->desc)
                return;

        dma_free_coherent(tx_ring->dev, tx_ring->size,
                          tx_ring->desc, tx_ring->dma);

        tx_ring->desc = NULL;
}

/**
 * igc_free_all_tx_resources - Free Tx Resources for All Queues
 * @adapter: board private structure
 *
 * Free all transmit software resources
 */
static void igc_free_all_tx_resources(struct igc_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                igc_free_tx_resources(adapter->tx_ring[i]);
}

/**
 * igc_clean_tx_ring - Free Tx Buffers
 * @tx_ring: ring to be cleaned
 */
static void igc_clean_tx_ring(struct igc_ring *tx_ring)
{
        u16 i = tx_ring->next_to_clean;
        struct igc_tx_buffer *tx_buffer = &tx_ring->tx_buffer_info[i];

        while (i != tx_ring->next_to_use) {
                union igc_adv_tx_desc *eop_desc, *tx_desc;

                /* Free all the Tx ring sk_buffs */
                dev_kfree_skb_any(tx_buffer->skb);

                /* unmap skb header data */
                dma_unmap_single(tx_ring->dev,
                                 dma_unmap_addr(tx_buffer, dma),
                                 dma_unmap_len(tx_buffer, len),
                                 DMA_TO_DEVICE);

                /* check for eop_desc to determine the end of the packet */
                eop_desc = tx_buffer->next_to_watch;
                tx_desc = IGC_TX_DESC(tx_ring, i);

                /* unmap remaining buffers */
                while (tx_desc != eop_desc) {
                        tx_buffer++;
                        tx_desc++;
                        i++;
                        if (unlikely(i == tx_ring->count)) {
                                i = 0;
                                tx_buffer = tx_ring->tx_buffer_info;
                                tx_desc = IGC_TX_DESC(tx_ring, 0);
                        }

                        /* unmap any remaining paged data */
                        if (dma_unmap_len(tx_buffer, len))
                                dma_unmap_page(tx_ring->dev,
                                               dma_unmap_addr(tx_buffer, dma),
                                               dma_unmap_len(tx_buffer, len),
                                               DMA_TO_DEVICE);
                }

                /* move us one more past the eop_desc for start of next pkt */
                tx_buffer++;
                i++;
                if (unlikely(i == tx_ring->count)) {
                        i = 0;
                        tx_buffer = tx_ring->tx_buffer_info;
                }
        }

        /* reset BQL for queue */
        netdev_tx_reset_queue(txring_txq(tx_ring));

        /* reset next_to_use and next_to_clean */
        tx_ring->next_to_use = 0;
        tx_ring->next_to_clean = 0;
}

/**
 * igc_clean_all_tx_rings - Free Tx Buffers for all queues
 * @adapter: board private structure
 */
static void igc_clean_all_tx_rings(struct igc_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                if (adapter->tx_ring[i])
                        igc_clean_tx_ring(adapter->tx_ring[i]);
}

/**
 * igc_setup_tx_resources - allocate Tx resources (Descriptors)
 * @tx_ring: tx descriptor ring (for a specific queue) to setup
 *
 * Return 0 on success, negative on failure
 */
int igc_setup_tx_resources(struct igc_ring *tx_ring)
{
        struct device *dev = tx_ring->dev;
        int size = 0;

        size = sizeof(struct igc_tx_buffer) * tx_ring->count;
        tx_ring->tx_buffer_info = vzalloc(size);
        if (!tx_ring->tx_buffer_info)
                goto err;

        /* round up to nearest 4K */
        tx_ring->size = tx_ring->count * sizeof(union igc_adv_tx_desc);
        tx_ring->size = ALIGN(tx_ring->size, 4096);

        tx_ring->desc = dma_alloc_coherent(dev, tx_ring->size,
                                           &tx_ring->dma, GFP_KERNEL);

        if (!tx_ring->desc)
                goto err;

        tx_ring->next_to_use = 0;
        tx_ring->next_to_clean = 0;

        return 0;

err:
        vfree(tx_ring->tx_buffer_info);
        dev_err(dev,
                "Unable to allocate memory for the transmit descriptor ring\n");
        return -ENOMEM;
}

/**
 * igc_setup_all_tx_resources - wrapper to allocate Tx resources for all queues
 * @adapter: board private structure
 *
 * Return 0 on success, negative on failure
 */
static int igc_setup_all_tx_resources(struct igc_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;
        int i, err = 0;

        for (i = 0; i < adapter->num_tx_queues; i++) {
                err = igc_setup_tx_resources(adapter->tx_ring[i]);
                if (err) {
                        dev_err(&pdev->dev,
                                "Allocation for Tx Queue %u failed\n", i);
                        for (i--; i >= 0; i--)
                                igc_free_tx_resources(adapter->tx_ring[i]);
                        break;
                }
        }

        return err;
}

/**
 * igc_clean_rx_ring - Free Rx Buffers per Queue
 * @rx_ring: ring to free buffers from
 */
static void igc_clean_rx_ring(struct igc_ring *rx_ring)
{
        u16 i = rx_ring->next_to_clean;

        if (rx_ring->skb)
                dev_kfree_skb(rx_ring->skb);
        rx_ring->skb = NULL;

        /* Free all the Rx ring sk_buffs */
        while (i != rx_ring->next_to_alloc) {
                struct igc_rx_buffer *buffer_info = &rx_ring->rx_buffer_info[i];

                /* Invalidate cache lines that may have been written to by
                 * device so that we avoid corrupting memory.
                 */
                dma_sync_single_range_for_cpu(rx_ring->dev,
                                              buffer_info->dma,
                                              buffer_info->page_offset,
                                              igc_rx_bufsz(rx_ring),
                                              DMA_FROM_DEVICE);

                /* free resources associated with mapping */
                dma_unmap_page_attrs(rx_ring->dev,
                                     buffer_info->dma,
                                     igc_rx_pg_size(rx_ring),
                                     DMA_FROM_DEVICE,
                                     IGC_RX_DMA_ATTR);
                __page_frag_cache_drain(buffer_info->page,
                                        buffer_info->pagecnt_bias);

                i++;
                if (i == rx_ring->count)
                        i = 0;
        }

        rx_ring->next_to_alloc = 0;
        rx_ring->next_to_clean = 0;
        rx_ring->next_to_use = 0;
}

/**
 * igc_clean_all_rx_rings - Free Rx Buffers for all queues
 * @adapter: board private structure
 */
static void igc_clean_all_rx_rings(struct igc_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_rx_queues; i++)
                if (adapter->rx_ring[i])
                        igc_clean_rx_ring(adapter->rx_ring[i]);
}

/**
 * igc_free_rx_resources - Free Rx Resources
 * @rx_ring: ring to clean the resources from
 *
 * Free all receive software resources
 */
void igc_free_rx_resources(struct igc_ring *rx_ring)
{
        igc_clean_rx_ring(rx_ring);

        vfree(rx_ring->rx_buffer_info);
        rx_ring->rx_buffer_info = NULL;

        /* if not set, then don't free */
        if (!rx_ring->desc)
                return;

        dma_free_coherent(rx_ring->dev, rx_ring->size,
                          rx_ring->desc, rx_ring->dma);

        rx_ring->desc = NULL;
}

/**
 * igc_free_all_rx_resources - Free Rx Resources for All Queues
 * @adapter: board private structure
 *
 * Free all receive software resources
 */
static void igc_free_all_rx_resources(struct igc_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_rx_queues; i++)
                igc_free_rx_resources(adapter->rx_ring[i]);
}

/**
 * igc_setup_rx_resources - allocate Rx resources (Descriptors)
 * @rx_ring:    rx descriptor ring (for a specific queue) to setup
 *
 * Returns 0 on success, negative on failure
 */
int igc_setup_rx_resources(struct igc_ring *rx_ring)
{
        struct device *dev = rx_ring->dev;
        int size, desc_len;

        size = sizeof(struct igc_rx_buffer) * rx_ring->count;
        rx_ring->rx_buffer_info = vzalloc(size);
        if (!rx_ring->rx_buffer_info)
                goto err;

        desc_len = sizeof(union igc_adv_rx_desc);

        /* Round up to nearest 4K */
        rx_ring->size = rx_ring->count * desc_len;
        rx_ring->size = ALIGN(rx_ring->size, 4096);

        rx_ring->desc = dma_alloc_coherent(dev, rx_ring->size,
                                           &rx_ring->dma, GFP_KERNEL);

        if (!rx_ring->desc)
                goto err;

        rx_ring->next_to_alloc = 0;
        rx_ring->next_to_clean = 0;
        rx_ring->next_to_use = 0;

        return 0;

err:
        vfree(rx_ring->rx_buffer_info);
        rx_ring->rx_buffer_info = NULL;
        dev_err(dev,
                "Unable to allocate memory for the receive descriptor ring\n");
        return -ENOMEM;
}

/**
 * igc_setup_all_rx_resources - wrapper to allocate Rx resources
 *                                (Descriptors) for all queues
 * @adapter: board private structure
 *
 * Return 0 on success, negative on failure
 */
static int igc_setup_all_rx_resources(struct igc_adapter *adapter)
{
        struct pci_dev *pdev = adapter->pdev;
        int i, err = 0;

        for (i = 0; i < adapter->num_rx_queues; i++) {
                err = igc_setup_rx_resources(adapter->rx_ring[i]);
                if (err) {
                        dev_err(&pdev->dev,
                                "Allocation for Rx Queue %u failed\n", i);
                        for (i--; i >= 0; i--)
                                igc_free_rx_resources(adapter->rx_ring[i]);
                        break;
                }
        }

        return err;
}

/**
 * igc_configure_rx_ring - Configure a receive ring after Reset
 * @adapter: board private structure
 * @ring: receive ring to be configured
 *
 * Configure the Rx unit of the MAC after a reset.
 */
static void igc_configure_rx_ring(struct igc_adapter *adapter,
                                  struct igc_ring *ring)
{
        struct igc_hw *hw = &adapter->hw;
        union igc_adv_rx_desc *rx_desc;
        int reg_idx = ring->reg_idx;
        u32 srrctl = 0, rxdctl = 0;
        u64 rdba = ring->dma;

        /* disable the queue */
        wr32(IGC_RXDCTL(reg_idx), 0);

        /* Set DMA base address registers */
        wr32(IGC_RDBAL(reg_idx),
             rdba & 0x00000000ffffffffULL);
        wr32(IGC_RDBAH(reg_idx), rdba >> 32);
        wr32(IGC_RDLEN(reg_idx),
             ring->count * sizeof(union igc_adv_rx_desc));

        /* initialize head and tail */
        ring->tail = adapter->io_addr + IGC_RDT(reg_idx);
        wr32(IGC_RDH(reg_idx), 0);
        writel(0, ring->tail);

        /* reset next-to- use/clean to place SW in sync with hardware */
        ring->next_to_clean = 0;
        ring->next_to_use = 0;

        /* set descriptor configuration */
        srrctl = IGC_RX_HDR_LEN << IGC_SRRCTL_BSIZEHDRSIZE_SHIFT;
        if (ring_uses_large_buffer(ring))
                srrctl |= IGC_RXBUFFER_3072 >> IGC_SRRCTL_BSIZEPKT_SHIFT;
        else
                srrctl |= IGC_RXBUFFER_2048 >> IGC_SRRCTL_BSIZEPKT_SHIFT;
        srrctl |= IGC_SRRCTL_DESCTYPE_ADV_ONEBUF;

        wr32(IGC_SRRCTL(reg_idx), srrctl);

        rxdctl |= IGC_RX_PTHRESH;
        rxdctl |= IGC_RX_HTHRESH << 8;
        rxdctl |= IGC_RX_WTHRESH << 16;

        /* initialize rx_buffer_info */
        memset(ring->rx_buffer_info, 0,
               sizeof(struct igc_rx_buffer) * ring->count);

        /* initialize Rx descriptor 0 */
        rx_desc = IGC_RX_DESC(ring, 0);
        rx_desc->wb.upper.length = 0;

        /* enable receive descriptor fetching */
        rxdctl |= IGC_RXDCTL_QUEUE_ENABLE;

        wr32(IGC_RXDCTL(reg_idx), rxdctl);
}

/**
 * igc_configure_rx - Configure receive Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Rx unit of the MAC after a reset.
 */
static void igc_configure_rx(struct igc_adapter *adapter)
{
        int i;

        /* Setup the HW Rx Head and Tail Descriptor Pointers and
         * the Base and Length of the Rx Descriptor Ring
         */
        for (i = 0; i < adapter->num_rx_queues; i++)
                igc_configure_rx_ring(adapter, adapter->rx_ring[i]);
}

/**
 * igc_configure_tx_ring - Configure transmit ring after Reset
 * @adapter: board private structure
 * @ring: tx ring to configure
 *
 * Configure a transmit ring after a reset.
 */
static void igc_configure_tx_ring(struct igc_adapter *adapter,
                                  struct igc_ring *ring)
{
        struct igc_hw *hw = &adapter->hw;
        int reg_idx = ring->reg_idx;
        u64 tdba = ring->dma;
        u32 txdctl = 0;

        /* disable the queue */
        wr32(IGC_TXDCTL(reg_idx), 0);
        wrfl();
        mdelay(10);

        wr32(IGC_TDLEN(reg_idx),
             ring->count * sizeof(union igc_adv_tx_desc));
        wr32(IGC_TDBAL(reg_idx),
             tdba & 0x00000000ffffffffULL);
        wr32(IGC_TDBAH(reg_idx), tdba >> 32);

        ring->tail = adapter->io_addr + IGC_TDT(reg_idx);
        wr32(IGC_TDH(reg_idx), 0);
        writel(0, ring->tail);

        txdctl |= IGC_TX_PTHRESH;
        txdctl |= IGC_TX_HTHRESH << 8;
        txdctl |= IGC_TX_WTHRESH << 16;

        txdctl |= IGC_TXDCTL_QUEUE_ENABLE;
        wr32(IGC_TXDCTL(reg_idx), txdctl);
}

/**
 * igc_configure_tx - Configure transmit Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Tx unit of the MAC after a reset.
 */
static void igc_configure_tx(struct igc_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                igc_configure_tx_ring(adapter, adapter->tx_ring[i]);
}

/**
 * igc_setup_mrqc - configure the multiple receive queue control registers
 * @adapter: Board private structure
 */
static void igc_setup_mrqc(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        u32 j, num_rx_queues;
        u32 mrqc, rxcsum;
        u32 rss_key[10];

        netdev_rss_key_fill(rss_key, sizeof(rss_key));
        for (j = 0; j < 10; j++)
                wr32(IGC_RSSRK(j), rss_key[j]);

        num_rx_queues = adapter->rss_queues;

        if (adapter->rss_indir_tbl_init != num_rx_queues) {
                for (j = 0; j < IGC_RETA_SIZE; j++)
                        adapter->rss_indir_tbl[j] =
                        (j * num_rx_queues) / IGC_RETA_SIZE;
                adapter->rss_indir_tbl_init = num_rx_queues;
        }
        igc_write_rss_indir_tbl(adapter);

        /* Disable raw packet checksumming so that RSS hash is placed in
         * descriptor on writeback.  No need to enable TCP/UDP/IP checksum
         * offloads as they are enabled by default
         */
        rxcsum = rd32(IGC_RXCSUM);
        rxcsum |= IGC_RXCSUM_PCSD;

        /* Enable Receive Checksum Offload for SCTP */
        rxcsum |= IGC_RXCSUM_CRCOFL;

        /* Don't need to set TUOFL or IPOFL, they default to 1 */
        wr32(IGC_RXCSUM, rxcsum);

        /* Generate RSS hash based on packet types, TCP/UDP
         * port numbers and/or IPv4/v6 src and dst addresses
         */
        mrqc = IGC_MRQC_RSS_FIELD_IPV4 |
               IGC_MRQC_RSS_FIELD_IPV4_TCP |
               IGC_MRQC_RSS_FIELD_IPV6 |
               IGC_MRQC_RSS_FIELD_IPV6_TCP |
               IGC_MRQC_RSS_FIELD_IPV6_TCP_EX;

        if (adapter->flags & IGC_FLAG_RSS_FIELD_IPV4_UDP)
                mrqc |= IGC_MRQC_RSS_FIELD_IPV4_UDP;
        if (adapter->flags & IGC_FLAG_RSS_FIELD_IPV6_UDP)
                mrqc |= IGC_MRQC_RSS_FIELD_IPV6_UDP;

        mrqc |= IGC_MRQC_ENABLE_RSS_MQ;

        wr32(IGC_MRQC, mrqc);
}

/**
 * igc_setup_rctl - configure the receive control registers
 * @adapter: Board private structure
 */
static void igc_setup_rctl(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        u32 rctl;

        rctl = rd32(IGC_RCTL);

        rctl &= ~(3 << IGC_RCTL_MO_SHIFT);
        rctl &= ~(IGC_RCTL_LBM_TCVR | IGC_RCTL_LBM_MAC);

        rctl |= IGC_RCTL_EN | IGC_RCTL_BAM | IGC_RCTL_RDMTS_HALF |
                (hw->mac.mc_filter_type << IGC_RCTL_MO_SHIFT);

        /* enable stripping of CRC. Newer features require
         * that the HW strips the CRC.
         */
        rctl |= IGC_RCTL_SECRC;

        /* disable store bad packets and clear size bits. */
        rctl &= ~(IGC_RCTL_SBP | IGC_RCTL_SZ_256);

        /* enable LPE to allow for reception of jumbo frames */
        rctl |= IGC_RCTL_LPE;

        /* disable queue 0 to prevent tail write w/o re-config */
        wr32(IGC_RXDCTL(0), 0);

        /* This is useful for sniffing bad packets. */
        if (adapter->netdev->features & NETIF_F_RXALL) {
                /* UPE and MPE will be handled by normal PROMISC logic
                 * in set_rx_mode
                 */
                rctl |= (IGC_RCTL_SBP | /* Receive bad packets */
                         IGC_RCTL_BAM | /* RX All Bcast Pkts */
                         IGC_RCTL_PMCF); /* RX All MAC Ctrl Pkts */

                rctl &= ~(IGC_RCTL_DPF | /* Allow filtered pause */
                          IGC_RCTL_CFIEN); /* Disable VLAN CFIEN Filter */
        }

        wr32(IGC_RCTL, rctl);
}

/**
 * igc_setup_tctl - configure the transmit control registers
 * @adapter: Board private structure
 */
static void igc_setup_tctl(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        u32 tctl;

        /* disable queue 0 which icould be enabled by default */
        wr32(IGC_TXDCTL(0), 0);

        /* Program the Transmit Control Register */
        tctl = rd32(IGC_TCTL);
        tctl &= ~IGC_TCTL_CT;
        tctl |= IGC_TCTL_PSP | IGC_TCTL_RTLC |
                (IGC_COLLISION_THRESHOLD << IGC_CT_SHIFT);

        /* Enable transmits */
        tctl |= IGC_TCTL_EN;

        wr32(IGC_TCTL, tctl);
}

/**
 * igc_set_mac - Change the Ethernet Address of the NIC
 * @netdev: network interface device structure
 * @p: pointer to an address structure
 *
 * Returns 0 on success, negative on failure
 */
static int igc_set_mac(struct net_device *netdev, void *p)
{
        struct igc_adapter *adapter = netdev_priv(netdev);
        struct igc_hw *hw = &adapter->hw;
        struct sockaddr *addr = p;

        if (!is_valid_ether_addr(addr->sa_data))
                return -EADDRNOTAVAIL;

        memcpy(netdev->dev_addr, addr->sa_data, netdev->addr_len);
        memcpy(hw->mac.addr, addr->sa_data, netdev->addr_len);

        /* set the correct pool for the new PF MAC address in entry 0 */
        igc_set_default_mac_filter(adapter);

        return 0;
}

static void igc_tx_csum(struct igc_ring *tx_ring, struct igc_tx_buffer *first)
{
}

static int __igc_maybe_stop_tx(struct igc_ring *tx_ring, const u16 size)
{
        struct net_device *netdev = tx_ring->netdev;

        netif_stop_subqueue(netdev, tx_ring->queue_index);

        /* memory barriier comment */
        smp_mb();

        /* We need to check again in a case another CPU has just
         * made room available.
         */
        if (igc_desc_unused(tx_ring) < size)
                return -EBUSY;

        /* A reprieve! */
        netif_wake_subqueue(netdev, tx_ring->queue_index);

        u64_stats_update_begin(&tx_ring->tx_syncp2);
        tx_ring->tx_stats.restart_queue2++;
        u64_stats_update_end(&tx_ring->tx_syncp2);

        return 0;
}

static inline int igc_maybe_stop_tx(struct igc_ring *tx_ring, const u16 size)
{
        if (igc_desc_unused(tx_ring) >= size)
                return 0;
        return __igc_maybe_stop_tx(tx_ring, size);
}

static u32 igc_tx_cmd_type(struct sk_buff *skb, u32 tx_flags)
{
        /* set type for advanced descriptor with frame checksum insertion */
        u32 cmd_type = IGC_ADVTXD_DTYP_DATA |
                       IGC_ADVTXD_DCMD_DEXT |
                       IGC_ADVTXD_DCMD_IFCS;

        return cmd_type;
}

static void igc_tx_olinfo_status(struct igc_ring *tx_ring,
                                 union igc_adv_tx_desc *tx_desc,
                                 u32 tx_flags, unsigned int paylen)
{
        u32 olinfo_status = paylen << IGC_ADVTXD_PAYLEN_SHIFT;

        /* insert L4 checksum */
        olinfo_status |= (tx_flags & IGC_TX_FLAGS_CSUM) *
                          ((IGC_TXD_POPTS_TXSM << 8) /
                          IGC_TX_FLAGS_CSUM);

        /* insert IPv4 checksum */
        olinfo_status |= (tx_flags & IGC_TX_FLAGS_IPV4) *
                          (((IGC_TXD_POPTS_IXSM << 8)) /
                          IGC_TX_FLAGS_IPV4);

        tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);
}

static int igc_tx_map(struct igc_ring *tx_ring,
                      struct igc_tx_buffer *first,
                      const u8 hdr_len)
{
        struct sk_buff *skb = first->skb;
        struct igc_tx_buffer *tx_buffer;
        union igc_adv_tx_desc *tx_desc;
        u32 tx_flags = first->tx_flags;
        struct skb_frag_struct *frag;
        u16 i = tx_ring->next_to_use;
        unsigned int data_len, size;
        dma_addr_t dma;
        u32 cmd_type = igc_tx_cmd_type(skb, tx_flags);

        tx_desc = IGC_TX_DESC(tx_ring, i);

        igc_tx_olinfo_status(tx_ring, tx_desc, tx_flags, skb->len - hdr_len);

        size = skb_headlen(skb);
        data_len = skb->data_len;

        dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);

        tx_buffer = first;

        for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
                if (dma_mapping_error(tx_ring->dev, dma))
                        goto dma_error;

                /* record length, and DMA address */
                dma_unmap_len_set(tx_buffer, len, size);
                dma_unmap_addr_set(tx_buffer, dma, dma);

                tx_desc->read.buffer_addr = cpu_to_le64(dma);

                while (unlikely(size > IGC_MAX_DATA_PER_TXD)) {
                        tx_desc->read.cmd_type_len =
                                cpu_to_le32(cmd_type ^ IGC_MAX_DATA_PER_TXD);

                        i++;
                        tx_desc++;
                        if (i == tx_ring->count) {
                                tx_desc = IGC_TX_DESC(tx_ring, 0);
                                i = 0;
                        }
                        tx_desc->read.olinfo_status = 0;

                        dma += IGC_MAX_DATA_PER_TXD;
                        size -= IGC_MAX_DATA_PER_TXD;

                        tx_desc->read.buffer_addr = cpu_to_le64(dma);
                }

                if (likely(!data_len))
                        break;

                tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type ^ size);

                i++;
                tx_desc++;
                if (i == tx_ring->count) {
                        tx_desc = IGC_TX_DESC(tx_ring, 0);
                        i = 0;
                }
                tx_desc->read.olinfo_status = 0;

                size = skb_frag_size(frag);
                data_len -= size;

                dma = skb_frag_dma_map(tx_ring->dev, frag, 0,
                                       size, DMA_TO_DEVICE);

                tx_buffer = &tx_ring->tx_buffer_info[i];
        }

        /* write last descriptor with RS and EOP bits */
        cmd_type |= size | IGC_TXD_DCMD;
        tx_desc->read.cmd_type_len = cpu_to_le32(cmd_type);

        netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);

        /* set the timestamp */
        first->time_stamp = jiffies;

        skb_tx_timestamp(skb);

        /* Force memory writes to complete before letting h/w know there
         * are new descriptors to fetch.  (Only applicable for weak-ordered
         * memory model archs, such as IA-64).
         *
         * We also need this memory barrier to make certain all of the
         * status bits have been updated before next_to_watch is written.
         */
        wmb();

        /* set next_to_watch value indicating a packet is present */
        first->next_to_watch = tx_desc;

        i++;
        if (i == tx_ring->count)
                i = 0;

        tx_ring->next_to_use = i;

        /* Make sure there is space in the ring for the next send. */
        igc_maybe_stop_tx(tx_ring, DESC_NEEDED);

        if (netif_xmit_stopped(txring_txq(tx_ring)) || !netdev_xmit_more()) {
                writel(i, tx_ring->tail);
        }

        return 0;
dma_error:
        dev_err(tx_ring->dev, "TX DMA map failed\n");
        tx_buffer = &tx_ring->tx_buffer_info[i];

        /* clear dma mappings for failed tx_buffer_info map */
        while (tx_buffer != first) {
                if (dma_unmap_len(tx_buffer, len))
                        dma_unmap_page(tx_ring->dev,
                                       dma_unmap_addr(tx_buffer, dma),
                                       dma_unmap_len(tx_buffer, len),
                                       DMA_TO_DEVICE);
                dma_unmap_len_set(tx_buffer, len, 0);

                if (i-- == 0)
                        i += tx_ring->count;
                tx_buffer = &tx_ring->tx_buffer_info[i];
        }

        if (dma_unmap_len(tx_buffer, len))
                dma_unmap_single(tx_ring->dev,
                                 dma_unmap_addr(tx_buffer, dma),
                                 dma_unmap_len(tx_buffer, len),
                                 DMA_TO_DEVICE);
        dma_unmap_len_set(tx_buffer, len, 0);

        dev_kfree_skb_any(tx_buffer->skb);
        tx_buffer->skb = NULL;

        tx_ring->next_to_use = i;

        return -1;
}

static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
                                       struct igc_ring *tx_ring)
{
        u16 count = TXD_USE_COUNT(skb_headlen(skb));
        __be16 protocol = vlan_get_protocol(skb);
        struct igc_tx_buffer *first;
        u32 tx_flags = 0;
        unsigned short f;
        u8 hdr_len = 0;

        /* need: 1 descriptor per page * PAGE_SIZE/IGC_MAX_DATA_PER_TXD,
         *      + 1 desc for skb_headlen/IGC_MAX_DATA_PER_TXD,
         *      + 2 desc gap to keep tail from touching head,
         *      + 1 desc for context descriptor,
         * otherwise try next time
         */
        for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
                count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);

        if (igc_maybe_stop_tx(tx_ring, count + 3)) {
                /* this is a hard error */
                return NETDEV_TX_BUSY;
        }

        /* record the location of the first descriptor for this packet */
        first = &tx_ring->tx_buffer_info[tx_ring->next_to_use];
        first->skb = skb;
        first->bytecount = skb->len;
        first->gso_segs = 1;

        /* record initial flags and protocol */
        first->tx_flags = tx_flags;
        first->protocol = protocol;

        igc_tx_csum(tx_ring, first);

        igc_tx_map(tx_ring, first, hdr_len);

        return NETDEV_TX_OK;
}

static inline struct igc_ring *igc_tx_queue_mapping(struct igc_adapter *adapter,
                                                    struct sk_buff *skb)
{
        unsigned int r_idx = skb->queue_mapping;

        if (r_idx >= adapter->num_tx_queues)
                r_idx = r_idx % adapter->num_tx_queues;

        return adapter->tx_ring[r_idx];
}

static netdev_tx_t igc_xmit_frame(struct sk_buff *skb,
                                  struct net_device *netdev)
{
        struct igc_adapter *adapter = netdev_priv(netdev);

        /* The minimum packet size with TCTL.PSP set is 17 so pad the skb
         * in order to meet this minimum size requirement.
         */
        if (skb->len < 17) {
                if (skb_padto(skb, 17))
                        return NETDEV_TX_OK;
                skb->len = 17;
        }

        return igc_xmit_frame_ring(skb, igc_tx_queue_mapping(adapter, skb));
}

static inline void igc_rx_hash(struct igc_ring *ring,
                               union igc_adv_rx_desc *rx_desc,
                               struct sk_buff *skb)
{
        if (ring->netdev->features & NETIF_F_RXHASH)
                skb_set_hash(skb,
                             le32_to_cpu(rx_desc->wb.lower.hi_dword.rss),
                             PKT_HASH_TYPE_L3);
}

/**
 * igc_process_skb_fields - Populate skb header fields from Rx descriptor
 * @rx_ring: rx descriptor ring packet is being transacted on
 * @rx_desc: pointer to the EOP Rx descriptor
 * @skb: pointer to current skb being populated
 *
 * This function checks the ring, descriptor, and packet information in
 * order to populate the hash, checksum, VLAN, timestamp, protocol, and
 * other fields within the skb.
 */
static void igc_process_skb_fields(struct igc_ring *rx_ring,
                                   union igc_adv_rx_desc *rx_desc,
                                   struct sk_buff *skb)
{
        igc_rx_hash(rx_ring, rx_desc, skb);

        skb_record_rx_queue(skb, rx_ring->queue_index);

        skb->protocol = eth_type_trans(skb, rx_ring->netdev);
}

static struct igc_rx_buffer *igc_get_rx_buffer(struct igc_ring *rx_ring,
                                               const unsigned int size)
{
        struct igc_rx_buffer *rx_buffer;

        rx_buffer = &rx_ring->rx_buffer_info[rx_ring->next_to_clean];
        prefetchw(rx_buffer->page);

        /* we are reusing so sync this buffer for CPU use */
        dma_sync_single_range_for_cpu(rx_ring->dev,
                                      rx_buffer->dma,
                                      rx_buffer->page_offset,
                                      size,
                                      DMA_FROM_DEVICE);

        rx_buffer->pagecnt_bias--;

        return rx_buffer;
}

/**
 * igc_add_rx_frag - Add contents of Rx buffer to sk_buff
 * @rx_ring: rx descriptor ring to transact packets on
 * @rx_buffer: buffer containing page to add
 * @skb: sk_buff to place the data into
 * @size: size of buffer to be added
 *
 * This function will add the data contained in rx_buffer->page to the skb.
 */
static void igc_add_rx_frag(struct igc_ring *rx_ring,
                            struct igc_rx_buffer *rx_buffer,
                            struct sk_buff *skb,
                            unsigned int size)
{
#if (PAGE_SIZE < 8192)
        unsigned int truesize = igc_rx_pg_size(rx_ring) / 2;

        skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
                        rx_buffer->page_offset, size, truesize);
        rx_buffer->page_offset ^= truesize;
#else
        unsigned int truesize = ring_uses_build_skb(rx_ring) ?
                                SKB_DATA_ALIGN(IGC_SKB_PAD + size) :
                                SKB_DATA_ALIGN(size);
        skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page,
                        rx_buffer->page_offset, size, truesize);
        rx_buffer->page_offset += truesize;
#endif
}

static struct sk_buff *igc_build_skb(struct igc_ring *rx_ring,
                                     struct igc_rx_buffer *rx_buffer,
                                     union igc_adv_rx_desc *rx_desc,
                                     unsigned int size)
{
        void *va = page_address(rx_buffer->page) + rx_buffer->page_offset;
#if (PAGE_SIZE < 8192)
        unsigned int truesize = igc_rx_pg_size(rx_ring) / 2;
#else
        unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
                                SKB_DATA_ALIGN(IGC_SKB_PAD + size);
#endif
        struct sk_buff *skb;

        /* prefetch first cache line of first page */
        prefetch(va);
#if L1_CACHE_BYTES < 128
        prefetch(va + L1_CACHE_BYTES);
#endif

        /* build an skb around the page buffer */
        skb = build_skb(va - IGC_SKB_PAD, truesize);
        if (unlikely(!skb))
                return NULL;

        /* update pointers within the skb to store the data */
        skb_reserve(skb, IGC_SKB_PAD);
        __skb_put(skb, size);

        /* update buffer offset */
#if (PAGE_SIZE < 8192)
        rx_buffer->page_offset ^= truesize;
#else
        rx_buffer->page_offset += truesize;
#endif

        return skb;
}

static struct sk_buff *igc_construct_skb(struct igc_ring *rx_ring,
                                         struct igc_rx_buffer *rx_buffer,
                                         union igc_adv_rx_desc *rx_desc,
                                         unsigned int size)
{
        void *va = page_address(rx_buffer->page) + rx_buffer->page_offset;
#if (PAGE_SIZE < 8192)
        unsigned int truesize = igc_rx_pg_size(rx_ring) / 2;
#else
        unsigned int truesize = SKB_DATA_ALIGN(size);
#endif
        unsigned int headlen;
        struct sk_buff *skb;

        /* prefetch first cache line of first page */
        prefetch(va);
#if L1_CACHE_BYTES < 128
        prefetch(va + L1_CACHE_BYTES);
#endif

        /* allocate a skb to store the frags */
        skb = napi_alloc_skb(&rx_ring->q_vector->napi, IGC_RX_HDR_LEN);
        if (unlikely(!skb))
                return NULL;

        /* Determine available headroom for copy */
        headlen = size;
        if (headlen > IGC_RX_HDR_LEN)
                headlen = eth_get_headlen(skb->dev, va, IGC_RX_HDR_LEN);

        /* align pull length to size of long to optimize memcpy performance */
        memcpy(__skb_put(skb, headlen), va, ALIGN(headlen, sizeof(long)));

        /* update all of the pointers */
        size -= headlen;
        if (size) {
                skb_add_rx_frag(skb, 0, rx_buffer->page,
                                (va + headlen) - page_address(rx_buffer->page),
                                size, truesize);
#if (PAGE_SIZE < 8192)
                rx_buffer->page_offset ^= truesize;
#else
                rx_buffer->page_offset += truesize;
#endif
        } else {
                rx_buffer->pagecnt_bias++;
        }

        return skb;
}

/**
 * igc_reuse_rx_page - page flip buffer and store it back on the ring
 * @rx_ring: rx descriptor ring to store buffers on
 * @old_buff: donor buffer to have page reused
 *
 * Synchronizes page for reuse by the adapter
 */
static void igc_reuse_rx_page(struct igc_ring *rx_ring,
                              struct igc_rx_buffer *old_buff)
{
        u16 nta = rx_ring->next_to_alloc;
        struct igc_rx_buffer *new_buff;

        new_buff = &rx_ring->rx_buffer_info[nta];

        /* update, and store next to alloc */
        nta++;
        rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;

        /* Transfer page from old buffer to new buffer.
         * Move each member individually to avoid possible store
         * forwarding stalls.
         */
        new_buff->dma           = old_buff->dma;
        new_buff->page          = old_buff->page;
        new_buff->page_offset   = old_buff->page_offset;
        new_buff->pagecnt_bias  = old_buff->pagecnt_bias;
}

static inline bool igc_page_is_reserved(struct page *page)
{
        return (page_to_nid(page) != numa_mem_id()) || page_is_pfmemalloc(page);
}

static bool igc_can_reuse_rx_page(struct igc_rx_buffer *rx_buffer)
{
        unsigned int pagecnt_bias = rx_buffer->pagecnt_bias;
        struct page *page = rx_buffer->page;

        /* avoid re-using remote pages */
        if (unlikely(igc_page_is_reserved(page)))
                return false;

#if (PAGE_SIZE < 8192)
        /* if we are only owner of page we can reuse it */
        if (unlikely((page_ref_count(page) - pagecnt_bias) > 1))
                return false;
#else
#define IGC_LAST_OFFSET \
        (SKB_WITH_OVERHEAD(PAGE_SIZE) - IGC_RXBUFFER_2048)

        if (rx_buffer->page_offset > IGC_LAST_OFFSET)
                return false;
#endif

        /* If we have drained the page fragment pool we need to update
         * the pagecnt_bias and page count so that we fully restock the
         * number of references the driver holds.
         */
        if (unlikely(!pagecnt_bias)) {
                page_ref_add(page, USHRT_MAX);
                rx_buffer->pagecnt_bias = USHRT_MAX;
        }

        return true;
}

/**
 * igc_is_non_eop - process handling of non-EOP buffers
 * @rx_ring: Rx ring being processed
 * @rx_desc: Rx descriptor for current buffer
 * @skb: current socket buffer containing buffer in progress
 *
 * This function updates next to clean.  If the buffer is an EOP buffer
 * this function exits returning false, otherwise it will place the
 * sk_buff in the next buffer to be chained and return true indicating
 * that this is in fact a non-EOP buffer.
 */
static bool igc_is_non_eop(struct igc_ring *rx_ring,
                           union igc_adv_rx_desc *rx_desc)
{
        u32 ntc = rx_ring->next_to_clean + 1;

        /* fetch, update, and store next to clean */
        ntc = (ntc < rx_ring->count) ? ntc : 0;
        rx_ring->next_to_clean = ntc;

        prefetch(IGC_RX_DESC(rx_ring, ntc));

        if (likely(igc_test_staterr(rx_desc, IGC_RXD_STAT_EOP)))
                return false;

        return true;
}

/**
 * igc_cleanup_headers - Correct corrupted or empty headers
 * @rx_ring: rx descriptor ring packet is being transacted on
 * @rx_desc: pointer to the EOP Rx descriptor
 * @skb: pointer to current skb being fixed
 *
 * Address the case where we are pulling data in on pages only
 * and as such no data is present in the skb header.
 *
 * In addition if skb is not at least 60 bytes we need to pad it so that
 * it is large enough to qualify as a valid Ethernet frame.
 *
 * Returns true if an error was encountered and skb was freed.
 */
static bool igc_cleanup_headers(struct igc_ring *rx_ring,
                                union igc_adv_rx_desc *rx_desc,
                                struct sk_buff *skb)
{
        if (unlikely((igc_test_staterr(rx_desc,
                                       IGC_RXDEXT_ERR_FRAME_ERR_MASK)))) {
                struct net_device *netdev = rx_ring->netdev;

                if (!(netdev->features & NETIF_F_RXALL)) {
                        dev_kfree_skb_any(skb);
                        return true;
                }
        }

        /* if eth_skb_pad returns an error the skb was freed */
        if (eth_skb_pad(skb))
                return true;

        return false;
}

static void igc_put_rx_buffer(struct igc_ring *rx_ring,
                              struct igc_rx_buffer *rx_buffer)
{
        if (igc_can_reuse_rx_page(rx_buffer)) {
                /* hand second half of page back to the ring */
                igc_reuse_rx_page(rx_ring, rx_buffer);
        } else {
                /* We are not reusing the buffer so unmap it and free
                 * any references we are holding to it
                 */
                dma_unmap_page_attrs(rx_ring->dev, rx_buffer->dma,
                                     igc_rx_pg_size(rx_ring), DMA_FROM_DEVICE,
                                     IGC_RX_DMA_ATTR);
                __page_frag_cache_drain(rx_buffer->page,
                                        rx_buffer->pagecnt_bias);
        }

        /* clear contents of rx_buffer */
        rx_buffer->page = NULL;
}

/**
 * igc_alloc_rx_buffers - Replace used receive buffers; packet split
 * @adapter: address of board private structure
 */
static void igc_alloc_rx_buffers(struct igc_ring *rx_ring, u16 cleaned_count)
{
        union igc_adv_rx_desc *rx_desc;
        u16 i = rx_ring->next_to_use;
        struct igc_rx_buffer *bi;
        u16 bufsz;

        /* nothing to do */
        if (!cleaned_count)
                return;

        rx_desc = IGC_RX_DESC(rx_ring, i);
        bi = &rx_ring->rx_buffer_info[i];
        i -= rx_ring->count;

        bufsz = igc_rx_bufsz(rx_ring);

        do {
                if (!igc_alloc_mapped_page(rx_ring, bi))
                        break;

                /* sync the buffer for use by the device */
                dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
                                                 bi->page_offset, bufsz,
                                                 DMA_FROM_DEVICE);

                /* Refresh the desc even if buffer_addrs didn't change
                 * because each write-back erases this info.
                 */
                rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);

                rx_desc++;
                bi++;
                i++;
                if (unlikely(!i)) {
                        rx_desc = IGC_RX_DESC(rx_ring, 0);
                        bi = rx_ring->rx_buffer_info;
                        i -= rx_ring->count;
                }

                /* clear the length for the next_to_use descriptor */
                rx_desc->wb.upper.length = 0;

                cleaned_count--;
        } while (cleaned_count);

        i += rx_ring->count;

        if (rx_ring->next_to_use != i) {
                /* record the next descriptor to use */
                rx_ring->next_to_use = i;

                /* update next to alloc since we have filled the ring */
                rx_ring->next_to_alloc = i;

                /* Force memory writes to complete before letting h/w
                 * know there are new descriptors to fetch.  (Only
                 * applicable for weak-ordered memory model archs,
                 * such as IA-64).
                 */
                wmb();
                writel(i, rx_ring->tail);
        }
}

static int igc_clean_rx_irq(struct igc_q_vector *q_vector, const int budget)
{
        unsigned int total_bytes = 0, total_packets = 0;
        struct igc_ring *rx_ring = q_vector->rx.ring;
        struct sk_buff *skb = rx_ring->skb;
        u16 cleaned_count = igc_desc_unused(rx_ring);

        while (likely(total_packets < budget)) {
                union igc_adv_rx_desc *rx_desc;
                struct igc_rx_buffer *rx_buffer;
                unsigned int size;

                /* return some buffers to hardware, one at a time is too slow */
                if (cleaned_count >= IGC_RX_BUFFER_WRITE) {
                        igc_alloc_rx_buffers(rx_ring, cleaned_count);
                        cleaned_count = 0;
                }

                rx_desc = IGC_RX_DESC(rx_ring, rx_ring->next_to_clean);
                size = le16_to_cpu(rx_desc->wb.upper.length);
                if (!size)
                        break;

                /* This memory barrier is needed to keep us from reading
                 * any other fields out of the rx_desc until we know the
                 * descriptor has been written back
                 */
                dma_rmb();

                rx_buffer = igc_get_rx_buffer(rx_ring, size);

                /* retrieve a buffer from the ring */
                if (skb)
                        igc_add_rx_frag(rx_ring, rx_buffer, skb, size);
                else if (ring_uses_build_skb(rx_ring))
                        skb = igc_build_skb(rx_ring, rx_buffer, rx_desc, size);
                else
                        skb = igc_construct_skb(rx_ring, rx_buffer,
                                                rx_desc, size);

                /* exit if we failed to retrieve a buffer */
                if (!skb) {
                        rx_ring->rx_stats.alloc_failed++;
                        rx_buffer->pagecnt_bias++;
                        break;
                }

                igc_put_rx_buffer(rx_ring, rx_buffer);
                cleaned_count++;

                /* fetch next buffer in frame if non-eop */
                if (igc_is_non_eop(rx_ring, rx_desc))
                        continue;

                /* verify the packet layout is correct */
                if (igc_cleanup_headers(rx_ring, rx_desc, skb)) {
                        skb = NULL;
                        continue;
                }

                /* probably a little skewed due to removing CRC */
                total_bytes += skb->len;

                /* populate checksum, timestamp, VLAN, and protocol */
                igc_process_skb_fields(rx_ring, rx_desc, skb);

                napi_gro_receive(&q_vector->napi, skb);

                /* reset skb pointer */
                skb = NULL;

                /* update budget accounting */
                total_packets++;
        }

        /* place incomplete frames back on ring for completion */
        rx_ring->skb = skb;

        u64_stats_update_begin(&rx_ring->rx_syncp);
        rx_ring->rx_stats.packets += total_packets;
        rx_ring->rx_stats.bytes += total_bytes;
        u64_stats_update_end(&rx_ring->rx_syncp);
        q_vector->rx.total_packets += total_packets;
        q_vector->rx.total_bytes += total_bytes;

        if (cleaned_count)
                igc_alloc_rx_buffers(rx_ring, cleaned_count);

        return total_packets;
}

static inline unsigned int igc_rx_offset(struct igc_ring *rx_ring)
{
        return ring_uses_build_skb(rx_ring) ? IGC_SKB_PAD : 0;
}

static bool igc_alloc_mapped_page(struct igc_ring *rx_ring,
                                  struct igc_rx_buffer *bi)
{
        struct page *page = bi->page;
        dma_addr_t dma;

        /* since we are recycling buffers we should seldom need to alloc */
        if (likely(page))
                return true;

        /* alloc new page for storage */
        page = dev_alloc_pages(igc_rx_pg_order(rx_ring));
        if (unlikely(!page)) {
                rx_ring->rx_stats.alloc_failed++;
                return false;
        }

        /* map page for use */
        dma = dma_map_page_attrs(rx_ring->dev, page, 0,
                                 igc_rx_pg_size(rx_ring),
                                 DMA_FROM_DEVICE,
                                 IGC_RX_DMA_ATTR);

        /* if mapping failed free memory back to system since
         * there isn't much point in holding memory we can't use
         */
        if (dma_mapping_error(rx_ring->dev, dma)) {
                __free_page(page);

                rx_ring->rx_stats.alloc_failed++;
                return false;
        }

        bi->dma = dma;
        bi->page = page;
        bi->page_offset = igc_rx_offset(rx_ring);
        bi->pagecnt_bias = 1;

        return true;
}

/**
 * igc_clean_tx_irq - Reclaim resources after transmit completes
 * @q_vector: pointer to q_vector containing needed info
 * @napi_budget: Used to determine if we are in netpoll
 *
 * returns true if ring is completely cleaned
 */
static bool igc_clean_tx_irq(struct igc_q_vector *q_vector, int napi_budget)
{
        struct igc_adapter *adapter = q_vector->adapter;
        unsigned int total_bytes = 0, total_packets = 0;
        unsigned int budget = q_vector->tx.work_limit;
        struct igc_ring *tx_ring = q_vector->tx.ring;
        unsigned int i = tx_ring->next_to_clean;
        struct igc_tx_buffer *tx_buffer;
        union igc_adv_tx_desc *tx_desc;

        if (test_bit(__IGC_DOWN, &adapter->state))
                return true;

        tx_buffer = &tx_ring->tx_buffer_info[i];
        tx_desc = IGC_TX_DESC(tx_ring, i);
        i -= tx_ring->count;

        do {
                union igc_adv_tx_desc *eop_desc = tx_buffer->next_to_watch;

                /* if next_to_watch is not set then there is no work pending */
                if (!eop_desc)
                        break;

                /* prevent any other reads prior to eop_desc */
                smp_rmb();

                /* if DD is not set pending work has not been completed */
                if (!(eop_desc->wb.status & cpu_to_le32(IGC_TXD_STAT_DD)))
                        break;

                /* clear next_to_watch to prevent false hangs */
                tx_buffer->next_to_watch = NULL;

                /* update the statistics for this packet */
                total_bytes += tx_buffer->bytecount;
                total_packets += tx_buffer->gso_segs;

                /* free the skb */
                napi_consume_skb(tx_buffer->skb, napi_budget);

                /* unmap skb header data */
                dma_unmap_single(tx_ring->dev,
                                 dma_unmap_addr(tx_buffer, dma),
                                 dma_unmap_len(tx_buffer, len),
                                 DMA_TO_DEVICE);

                /* clear tx_buffer data */
                dma_unmap_len_set(tx_buffer, len, 0);

                /* clear last DMA location and unmap remaining buffers */
                while (tx_desc != eop_desc) {
                        tx_buffer++;
                        tx_desc++;
                        i++;
                        if (unlikely(!i)) {
                                i -= tx_ring->count;
                                tx_buffer = tx_ring->tx_buffer_info;
                                tx_desc = IGC_TX_DESC(tx_ring, 0);
                        }

                        /* unmap any remaining paged data */
                        if (dma_unmap_len(tx_buffer, len)) {
                                dma_unmap_page(tx_ring->dev,
                                               dma_unmap_addr(tx_buffer, dma),
                                               dma_unmap_len(tx_buffer, len),
                                               DMA_TO_DEVICE);
                                dma_unmap_len_set(tx_buffer, len, 0);
                        }
                }

                /* move us one more past the eop_desc for start of next pkt */
                tx_buffer++;
                tx_desc++;
                i++;
                if (unlikely(!i)) {
                        i -= tx_ring->count;
                        tx_buffer = tx_ring->tx_buffer_info;
                        tx_desc = IGC_TX_DESC(tx_ring, 0);
                }

                /* issue prefetch for next Tx descriptor */
                prefetch(tx_desc);

                /* update budget accounting */
                budget--;
        } while (likely(budget));

        netdev_tx_completed_queue(txring_txq(tx_ring),
                                  total_packets, total_bytes);

        i += tx_ring->count;
        tx_ring->next_to_clean = i;
        u64_stats_update_begin(&tx_ring->tx_syncp);
        tx_ring->tx_stats.bytes += total_bytes;
        tx_ring->tx_stats.packets += total_packets;
        u64_stats_update_end(&tx_ring->tx_syncp);
        q_vector->tx.total_bytes += total_bytes;
        q_vector->tx.total_packets += total_packets;

        if (test_bit(IGC_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags)) {
                struct igc_hw *hw = &adapter->hw;

                /* Detect a transmit hang in hardware, this serializes the
                 * check with the clearing of time_stamp and movement of i
                 */
                clear_bit(IGC_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags);
                if (tx_buffer->next_to_watch &&
                    time_after(jiffies, tx_buffer->time_stamp +
                    (adapter->tx_timeout_factor * HZ)) &&
                    !(rd32(IGC_STATUS) & IGC_STATUS_TXOFF)) {
                        /* detected Tx unit hang */
                        dev_err(tx_ring->dev,
                                "Detected Tx Unit Hang\n"
                                "  Tx Queue             <%d>\n"
                                "  TDH                  <%x>\n"
                                "  TDT                  <%x>\n"
                                "  next_to_use          <%x>\n"
                                "  next_to_clean        <%x>\n"
                                "buffer_info[next_to_clean]\n"
                                "  time_stamp           <%lx>\n"
                                "  next_to_watch        <%p>\n"
                                "  jiffies              <%lx>\n"
                                "  desc.status          <%x>\n",
                                tx_ring->queue_index,
                                rd32(IGC_TDH(tx_ring->reg_idx)),
                                readl(tx_ring->tail),
                                tx_ring->next_to_use,
                                tx_ring->next_to_clean,
                                tx_buffer->time_stamp,
                                tx_buffer->next_to_watch,
                                jiffies,
                                tx_buffer->next_to_watch->wb.status);
                        netif_stop_subqueue(tx_ring->netdev,
                                            tx_ring->queue_index);

                        /* we are about to reset, no point in enabling stuff */
                        return true;
                }
        }

#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
        if (unlikely(total_packets &&
                     netif_carrier_ok(tx_ring->netdev) &&
                     igc_desc_unused(tx_ring) >= TX_WAKE_THRESHOLD)) {
                /* Make sure that anybody stopping the queue after this
                 * sees the new next_to_clean.
                 */
                smp_mb();
                if (__netif_subqueue_stopped(tx_ring->netdev,
                                             tx_ring->queue_index) &&
                    !(test_bit(__IGC_DOWN, &adapter->state))) {
                        netif_wake_subqueue(tx_ring->netdev,
                                            tx_ring->queue_index);

                        u64_stats_update_begin(&tx_ring->tx_syncp);
                        tx_ring->tx_stats.restart_queue++;
                        u64_stats_update_end(&tx_ring->tx_syncp);
                }
        }

        return !!budget;
}

/**
 * igc_up - Open the interface and prepare it to handle traffic
 * @adapter: board private structure
 */
void igc_up(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        int i = 0;

        /* hardware has been reset, we need to reload some things */
        igc_configure(adapter);

        clear_bit(__IGC_DOWN, &adapter->state);

        for (i = 0; i < adapter->num_q_vectors; i++)
                napi_enable(&adapter->q_vector[i]->napi);

        if (adapter->msix_entries)
                igc_configure_msix(adapter);
        else
                igc_assign_vector(adapter->q_vector[0], 0);

        /* Clear any pending interrupts. */
        rd32(IGC_ICR);
        igc_irq_enable(adapter);

        netif_tx_start_all_queues(adapter->netdev);

        /* start the watchdog. */
        hw->mac.get_link_status = 1;
        schedule_work(&adapter->watchdog_task);
}

/**
 * igc_update_stats - Update the board statistics counters
 * @adapter: board private structure
 */
void igc_update_stats(struct igc_adapter *adapter)
{
        struct rtnl_link_stats64 *net_stats = &adapter->stats64;
        struct pci_dev *pdev = adapter->pdev;
        struct igc_hw *hw = &adapter->hw;
        u64 _bytes, _packets;
        u64 bytes, packets;
        unsigned int start;
        u32 mpc;
        int i;

        /* Prevent stats update while adapter is being reset, or if the pci
         * connection is down.
         */
        if (adapter->link_speed == 0)
                return;
        if (pci_channel_offline(pdev))
                return;

        packets = 0;
        bytes = 0;

        rcu_read_lock();
        for (i = 0; i < adapter->num_rx_queues; i++) {
                struct igc_ring *ring = adapter->rx_ring[i];
                u32 rqdpc = rd32(IGC_RQDPC(i));

                if (hw->mac.type >= igc_i225)
                        wr32(IGC_RQDPC(i), 0);

                if (rqdpc) {
                        ring->rx_stats.drops += rqdpc;
                        net_stats->rx_fifo_errors += rqdpc;
                }

                do {
                        start = u64_stats_fetch_begin_irq(&ring->rx_syncp);
                        _bytes = ring->rx_stats.bytes;
                        _packets = ring->rx_stats.packets;
                } while (u64_stats_fetch_retry_irq(&ring->rx_syncp, start));
                bytes += _bytes;
                packets += _packets;
        }

        net_stats->rx_bytes = bytes;
        net_stats->rx_packets = packets;

        packets = 0;
        bytes = 0;
        for (i = 0; i < adapter->num_tx_queues; i++) {
                struct igc_ring *ring = adapter->tx_ring[i];

                do {
                        start = u64_stats_fetch_begin_irq(&ring->tx_syncp);
                        _bytes = ring->tx_stats.bytes;
                        _packets = ring->tx_stats.packets;
                } while (u64_stats_fetch_retry_irq(&ring->tx_syncp, start));
                bytes += _bytes;
                packets += _packets;
        }
        net_stats->tx_bytes = bytes;
        net_stats->tx_packets = packets;
        rcu_read_unlock();

        /* read stats registers */
        adapter->stats.crcerrs += rd32(IGC_CRCERRS);
        adapter->stats.gprc += rd32(IGC_GPRC);
        adapter->stats.gorc += rd32(IGC_GORCL);
        rd32(IGC_GORCH); /* clear GORCL */
        adapter->stats.bprc += rd32(IGC_BPRC);
        adapter->stats.mprc += rd32(IGC_MPRC);
        adapter->stats.roc += rd32(IGC_ROC);

        adapter->stats.prc64 += rd32(IGC_PRC64);
        adapter->stats.prc127 += rd32(IGC_PRC127);
        adapter->stats.prc255 += rd32(IGC_PRC255);
        adapter->stats.prc511 += rd32(IGC_PRC511);
        adapter->stats.prc1023 += rd32(IGC_PRC1023);
        adapter->stats.prc1522 += rd32(IGC_PRC1522);
        adapter->stats.symerrs += rd32(IGC_SYMERRS);
        adapter->stats.sec += rd32(IGC_SEC);

        mpc = rd32(IGC_MPC);
        adapter->stats.mpc += mpc;
        net_stats->rx_fifo_errors += mpc;
        adapter->stats.scc += rd32(IGC_SCC);
        adapter->stats.ecol += rd32(IGC_ECOL);
        adapter->stats.mcc += rd32(IGC_MCC);
        adapter->stats.latecol += rd32(IGC_LATECOL);
        adapter->stats.dc += rd32(IGC_DC);
        adapter->stats.rlec += rd32(IGC_RLEC);
        adapter->stats.xonrxc += rd32(IGC_XONRXC);
        adapter->stats.xontxc += rd32(IGC_XONTXC);
        adapter->stats.xoffrxc += rd32(IGC_XOFFRXC);
        adapter->stats.xofftxc += rd32(IGC_XOFFTXC);
        adapter->stats.fcruc += rd32(IGC_FCRUC);
        adapter->stats.gptc += rd32(IGC_GPTC);
        adapter->stats.gotc += rd32(IGC_GOTCL);
        rd32(IGC_GOTCH); /* clear GOTCL */
        adapter->stats.rnbc += rd32(IGC_RNBC);
        adapter->stats.ruc += rd32(IGC_RUC);
        adapter->stats.rfc += rd32(IGC_RFC);
        adapter->stats.rjc += rd32(IGC_RJC);
        adapter->stats.tor += rd32(IGC_TORH);
        adapter->stats.tot += rd32(IGC_TOTH);
        adapter->stats.tpr += rd32(IGC_TPR);

        adapter->stats.ptc64 += rd32(IGC_PTC64);
        adapter->stats.ptc127 += rd32(IGC_PTC127);
        adapter->stats.ptc255 += rd32(IGC_PTC255);
        adapter->stats.ptc511 += rd32(IGC_PTC511);
        adapter->stats.ptc1023 += rd32(IGC_PTC1023);
        adapter->stats.ptc1522 += rd32(IGC_PTC1522);

        adapter->stats.mptc += rd32(IGC_MPTC);
        adapter->stats.bptc += rd32(IGC_BPTC);

        adapter->stats.tpt += rd32(IGC_TPT);
        adapter->stats.colc += rd32(IGC_COLC);

        adapter->stats.algnerrc += rd32(IGC_ALGNERRC);

        adapter->stats.tsctc += rd32(IGC_TSCTC);
        adapter->stats.tsctfc += rd32(IGC_TSCTFC);

        adapter->stats.iac += rd32(IGC_IAC);
        adapter->stats.icrxoc += rd32(IGC_ICRXOC);
        adapter->stats.icrxptc += rd32(IGC_ICRXPTC);
        adapter->stats.icrxatc += rd32(IGC_ICRXATC);
        adapter->stats.ictxptc += rd32(IGC_ICTXPTC);
        adapter->stats.ictxatc += rd32(IGC_ICTXATC);
        adapter->stats.ictxqec += rd32(IGC_ICTXQEC);
        adapter->stats.ictxqmtc += rd32(IGC_ICTXQMTC);
        adapter->stats.icrxdmtc += rd32(IGC_ICRXDMTC);

        /* Fill out the OS statistics structure */
        net_stats->multicast = adapter->stats.mprc;
        net_stats->collisions = adapter->stats.colc;

        /* Rx Errors */

        /* RLEC on some newer hardware can be incorrect so build
         * our own version based on RUC and ROC
         */
        net_stats->rx_errors = adapter->stats.rxerrc +
                adapter->stats.crcerrs + adapter->stats.algnerrc +
                adapter->stats.ruc + adapter->stats.roc +
                adapter->stats.cexterr;
        net_stats->rx_length_errors = adapter->stats.ruc +
                                      adapter->stats.roc;
        net_stats->rx_crc_errors = adapter->stats.crcerrs;
        net_stats->rx_frame_errors = adapter->stats.algnerrc;
        net_stats->rx_missed_errors = adapter->stats.mpc;

        /* Tx Errors */
        net_stats->tx_errors = adapter->stats.ecol +
                               adapter->stats.latecol;
        net_stats->tx_aborted_errors = adapter->stats.ecol;
        net_stats->tx_window_errors = adapter->stats.latecol;
        net_stats->tx_carrier_errors = adapter->stats.tncrs;

        /* Tx Dropped needs to be maintained elsewhere */

        /* Management Stats */
        adapter->stats.mgptc += rd32(IGC_MGTPTC);
        adapter->stats.mgprc += rd32(IGC_MGTPRC);
        adapter->stats.mgpdc += rd32(IGC_MGTPDC);
}

static void igc_nfc_filter_exit(struct igc_adapter *adapter)
{
        struct igc_nfc_filter *rule;

        spin_lock(&adapter->nfc_lock);

        hlist_for_each_entry(rule, &adapter->nfc_filter_list, nfc_node)
                igc_erase_filter(adapter, rule);

        hlist_for_each_entry(rule, &adapter->cls_flower_list, nfc_node)
                igc_erase_filter(adapter, rule);

        spin_unlock(&adapter->nfc_lock);
}

static void igc_nfc_filter_restore(struct igc_adapter *adapter)
{
        struct igc_nfc_filter *rule;

        spin_lock(&adapter->nfc_lock);

        hlist_for_each_entry(rule, &adapter->nfc_filter_list, nfc_node)
                igc_add_filter(adapter, rule);

        spin_unlock(&adapter->nfc_lock);
}

/**
 * igc_down - Close the interface
 * @adapter: board private structure
 */
void igc_down(struct igc_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct igc_hw *hw = &adapter->hw;
        u32 tctl, rctl;
        int i = 0;

        set_bit(__IGC_DOWN, &adapter->state);

        /* disable receives in the hardware */
        rctl = rd32(IGC_RCTL);
        wr32(IGC_RCTL, rctl & ~IGC_RCTL_EN);
        /* flush and sleep below */

        igc_nfc_filter_exit(adapter);

        /* set trans_start so we don't get spurious watchdogs during reset */
        netif_trans_update(netdev);

        netif_carrier_off(netdev);
        netif_tx_stop_all_queues(netdev);

        /* disable transmits in the hardware */
        tctl = rd32(IGC_TCTL);
        tctl &= ~IGC_TCTL_EN;
        wr32(IGC_TCTL, tctl);
        /* flush both disables and wait for them to finish */
        wrfl();
        usleep_range(10000, 20000);

        igc_irq_disable(adapter);

        adapter->flags &= ~IGC_FLAG_NEED_LINK_UPDATE;

        for (i = 0; i < adapter->num_q_vectors; i++) {
                if (adapter->q_vector[i]) {
                        napi_synchronize(&adapter->q_vector[i]->napi);
                        napi_disable(&adapter->q_vector[i]->napi);
                }
        }

        del_timer_sync(&adapter->watchdog_timer);
        del_timer_sync(&adapter->phy_info_timer);

        /* record the stats before reset*/
        spin_lock(&adapter->stats64_lock);
        igc_update_stats(adapter);
        spin_unlock(&adapter->stats64_lock);

        adapter->link_speed = 0;
        adapter->link_duplex = 0;

        if (!pci_channel_offline(adapter->pdev))
                igc_reset(adapter);

        /* clear VLAN promisc flag so VFTA will be updated if necessary */
        adapter->flags &= ~IGC_FLAG_VLAN_PROMISC;

        igc_clean_all_tx_rings(adapter);
        igc_clean_all_rx_rings(adapter);
}

void igc_reinit_locked(struct igc_adapter *adapter)
{
        WARN_ON(in_interrupt());
        while (test_and_set_bit(__IGC_RESETTING, &adapter->state))
                usleep_range(1000, 2000);
        igc_down(adapter);
        igc_up(adapter);
        clear_bit(__IGC_RESETTING, &adapter->state);
}

static void igc_reset_task(struct work_struct *work)
{
        struct igc_adapter *adapter;

        adapter = container_of(work, struct igc_adapter, reset_task);

        netdev_err(adapter->netdev, "Reset adapter\n");
        igc_reinit_locked(adapter);
}

/**
 * igc_change_mtu - Change the Maximum Transfer Unit
 * @netdev: network interface device structure
 * @new_mtu: new value for maximum frame size
 *
 * Returns 0 on success, negative on failure
 */
static int igc_change_mtu(struct net_device *netdev, int new_mtu)
{
        int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
        struct igc_adapter *adapter = netdev_priv(netdev);
        struct pci_dev *pdev = adapter->pdev;

        /* adjust max frame to be at least the size of a standard frame */
        if (max_frame < (ETH_FRAME_LEN + ETH_FCS_LEN))
                max_frame = ETH_FRAME_LEN + ETH_FCS_LEN;

        while (test_and_set_bit(__IGC_RESETTING, &adapter->state))
                usleep_range(1000, 2000);

        /* igc_down has a dependency on max_frame_size */
        adapter->max_frame_size = max_frame;

        if (netif_running(netdev))
                igc_down(adapter);

        dev_info(&pdev->dev, "changing MTU from %d to %d\n",
                 netdev->mtu, new_mtu);
        netdev->mtu = new_mtu;

        if (netif_running(netdev))
                igc_up(adapter);
        else
                igc_reset(adapter);

        clear_bit(__IGC_RESETTING, &adapter->state);

        return 0;
}

/**
 * igc_get_stats - Get System Network Statistics
 * @netdev: network interface device structure
 *
 * Returns the address of the device statistics structure.
 * The statistics are updated here and also from the timer callback.
 */
static struct net_device_stats *igc_get_stats(struct net_device *netdev)
{
        struct igc_adapter *adapter = netdev_priv(netdev);

        if (!test_bit(__IGC_RESETTING, &adapter->state))
                igc_update_stats(adapter);

        /* only return the current stats */
        return &netdev->stats;
}

static netdev_features_t igc_fix_features(struct net_device *netdev,
                                          netdev_features_t features)
{
        /* Since there is no support for separate Rx/Tx vlan accel
         * enable/disable make sure Tx flag is always in same state as Rx.
         */
        if (features & NETIF_F_HW_VLAN_CTAG_RX)
                features |= NETIF_F_HW_VLAN_CTAG_TX;
        else
                features &= ~NETIF_F_HW_VLAN_CTAG_TX;

        return features;
}

static int igc_set_features(struct net_device *netdev,
                            netdev_features_t features)
{
        netdev_features_t changed = netdev->features ^ features;
        struct igc_adapter *adapter = netdev_priv(netdev);

        /* Add VLAN support */
        if (!(changed & (NETIF_F_RXALL | NETIF_F_NTUPLE)))
                return 0;

        if (!(features & NETIF_F_NTUPLE)) {
                struct hlist_node *node2;
                struct igc_nfc_filter *rule;

                spin_lock(&adapter->nfc_lock);
                hlist_for_each_entry_safe(rule, node2,
                                          &adapter->nfc_filter_list, nfc_node) {
                        igc_erase_filter(adapter, rule);
                        hlist_del(&rule->nfc_node);
                        kfree(rule);
                }
                spin_unlock(&adapter->nfc_lock);
                adapter->nfc_filter_count = 0;
        }

        netdev->features = features;

        if (netif_running(netdev))
                igc_reinit_locked(adapter);
        else
                igc_reset(adapter);

        return 1;
}

static netdev_features_t
igc_features_check(struct sk_buff *skb, struct net_device *dev,
                   netdev_features_t features)
{
        unsigned int network_hdr_len, mac_hdr_len;

        /* Make certain the headers can be described by a context descriptor */
        mac_hdr_len = skb_network_header(skb) - skb->data;
        if (unlikely(mac_hdr_len > IGC_MAX_MAC_HDR_LEN))
                return features & ~(NETIF_F_HW_CSUM |
                                    NETIF_F_SCTP_CRC |
                                    NETIF_F_HW_VLAN_CTAG_TX |
                                    NETIF_F_TSO |
                                    NETIF_F_TSO6);

        network_hdr_len = skb_checksum_start(skb) - skb_network_header(skb);
        if (unlikely(network_hdr_len >  IGC_MAX_NETWORK_HDR_LEN))
                return features & ~(NETIF_F_HW_CSUM |
                                    NETIF_F_SCTP_CRC |
                                    NETIF_F_TSO |
                                    NETIF_F_TSO6);

        /* We can only support IPv4 TSO in tunnels if we can mangle the
         * inner IP ID field, so strip TSO if MANGLEID is not supported.
         */
        if (skb->encapsulation && !(features & NETIF_F_TSO_MANGLEID))
                features &= ~NETIF_F_TSO;

        return features;
}

/**
 * igc_configure - configure the hardware for RX and TX
 * @adapter: private board structure
 */
static void igc_configure(struct igc_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int i = 0;

        igc_get_hw_control(adapter);
        igc_set_rx_mode(netdev);

        igc_setup_tctl(adapter);
        igc_setup_mrqc(adapter);
        igc_setup_rctl(adapter);

        igc_nfc_filter_restore(adapter);
        igc_configure_tx(adapter);
        igc_configure_rx(adapter);

        igc_rx_fifo_flush_base(&adapter->hw);

        /* call igc_desc_unused which always leaves
         * at least 1 descriptor unused to make sure
         * next_to_use != next_to_clean
         */
        for (i = 0; i < adapter->num_rx_queues; i++) {
                struct igc_ring *ring = adapter->rx_ring[i];

                igc_alloc_rx_buffers(ring, igc_desc_unused(ring));
        }
}

/**
 * igc_rar_set_index - Sync RAL[index] and RAH[index] registers with MAC table
 * @adapter: address of board private structure
 * @index: Index of the RAR entry which need to be synced with MAC table
 */
static void igc_rar_set_index(struct igc_adapter *adapter, u32 index)
{
        u8 *addr = adapter->mac_table[index].addr;
        struct igc_hw *hw = &adapter->hw;
        u32 rar_low, rar_high;

        /* HW expects these to be in network order when they are plugged
         * into the registers which are little endian.  In order to guarantee
         * that ordering we need to do an leXX_to_cpup here in order to be
         * ready for the byteswap that occurs with writel
         */
        rar_low = le32_to_cpup((__le32 *)(addr));
        rar_high = le16_to_cpup((__le16 *)(addr + 4));

        /* Indicate to hardware the Address is Valid. */
        if (adapter->mac_table[index].state & IGC_MAC_STATE_IN_USE) {
                if (is_valid_ether_addr(addr))
                        rar_high |= IGC_RAH_AV;

                rar_high |= IGC_RAH_POOL_1 <<
                        adapter->mac_table[index].queue;
        }

        wr32(IGC_RAL(index), rar_low);
        wrfl();
        wr32(IGC_RAH(index), rar_high);
        wrfl();
}

/* Set default MAC address for the PF in the first RAR entry */
static void igc_set_default_mac_filter(struct igc_adapter *adapter)
{
        struct igc_mac_addr *mac_table = &adapter->mac_table[0];

        ether_addr_copy(mac_table->addr, adapter->hw.mac.addr);
        mac_table->state = IGC_MAC_STATE_DEFAULT | IGC_MAC_STATE_IN_USE;

        igc_rar_set_index(adapter, 0);
}

/* If the filter to be added and an already existing filter express
 * the same address and address type, it should be possible to only
 * override the other configurations, for example the queue to steer
 * traffic.
 */
static bool igc_mac_entry_can_be_used(const struct igc_mac_addr *entry,
                                      const u8 *addr, const u8 flags)
{
        if (!(entry->state & IGC_MAC_STATE_IN_USE))
                return true;

        if ((entry->state & IGC_MAC_STATE_SRC_ADDR) !=
            (flags & IGC_MAC_STATE_SRC_ADDR))
                return false;

        if (!ether_addr_equal(addr, entry->addr))
                return false;

        return true;
}

/* Add a MAC filter for 'addr' directing matching traffic to 'queue',
 * 'flags' is used to indicate what kind of match is made, match is by
 * default for the destination address, if matching by source address
 * is desired the flag IGC_MAC_STATE_SRC_ADDR can be used.
 */
static int igc_add_mac_filter_flags(struct igc_adapter *adapter,
                                    const u8 *addr, const u8 queue,
                                    const u8 flags)
{
        struct igc_hw *hw = &adapter->hw;
        int rar_entries = hw->mac.rar_entry_count;
        int i;

        if (is_zero_ether_addr(addr))
                return -EINVAL;

        /* Search for the first empty entry in the MAC table.
         * Do not touch entries at the end of the table reserved for the VF MAC
         * addresses.
         */
        for (i = 0; i < rar_entries; i++) {
                if (!igc_mac_entry_can_be_used(&adapter->mac_table[i],
                                               addr, flags))
                        continue;

                ether_addr_copy(adapter->mac_table[i].addr, addr);
                adapter->mac_table[i].queue = queue;
                adapter->mac_table[i].state |= IGC_MAC_STATE_IN_USE | flags;

                igc_rar_set_index(adapter, i);
                return i;
        }

        return -ENOSPC;
}

int igc_add_mac_steering_filter(struct igc_adapter *adapter,
                                const u8 *addr, u8 queue, u8 flags)
{
        return igc_add_mac_filter_flags(adapter, addr, queue,
                                        IGC_MAC_STATE_QUEUE_STEERING | flags);
}

/* Remove a MAC filter for 'addr' directing matching traffic to
 * 'queue', 'flags' is used to indicate what kind of match need to be
 * removed, match is by default for the destination address, if
 * matching by source address is to be removed the flag
 * IGC_MAC_STATE_SRC_ADDR can be used.
 */
static int igc_del_mac_filter_flags(struct igc_adapter *adapter,
                                    const u8 *addr, const u8 queue,
                                    const u8 flags)
{
        struct igc_hw *hw = &adapter->hw;
        int rar_entries = hw->mac.rar_entry_count;
        int i;

        if (is_zero_ether_addr(addr))
                return -EINVAL;

        /* Search for matching entry in the MAC table based on given address
         * and queue. Do not touch entries at the end of the table reserved
         * for the VF MAC addresses.
         */
        for (i = 0; i < rar_entries; i++) {
                if (!(adapter->mac_table[i].state & IGC_MAC_STATE_IN_USE))
                        continue;
                if ((adapter->mac_table[i].state & flags) != flags)
                        continue;
                if (adapter->mac_table[i].queue != queue)
                        continue;
                if (!ether_addr_equal(adapter->mac_table[i].addr, addr))
                        continue;

                /* When a filter for the default address is "deleted",
                 * we return it to its initial configuration
                 */
                if (adapter->mac_table[i].state & IGC_MAC_STATE_DEFAULT) {
                        adapter->mac_table[i].state =
                                IGC_MAC_STATE_DEFAULT | IGC_MAC_STATE_IN_USE;
                } else {
                        adapter->mac_table[i].state = 0;
                        adapter->mac_table[i].queue = 0;
                        memset(adapter->mac_table[i].addr, 0, ETH_ALEN);
                }

                igc_rar_set_index(adapter, i);
                return 0;
        }

        return -ENOENT;
}

int igc_del_mac_steering_filter(struct igc_adapter *adapter,
                                const u8 *addr, u8 queue, u8 flags)
{
        return igc_del_mac_filter_flags(adapter, addr, queue,
                                        IGC_MAC_STATE_QUEUE_STEERING | flags);
}

/**
 * igc_set_rx_mode - Secondary Unicast, Multicast and Promiscuous mode set
 * @netdev: network interface device structure
 *
 * The set_rx_mode entry point is called whenever the unicast or multicast
 * address lists or the network interface flags are updated.  This routine is
 * responsible for configuring the hardware for proper unicast, multicast,
 * promiscuous mode, and all-multi behavior.
 */
static void igc_set_rx_mode(struct net_device *netdev)
{
}

/**
 * igc_msix_other - msix other interrupt handler
 * @irq: interrupt number
 * @data: pointer to a q_vector
 */
static irqreturn_t igc_msix_other(int irq, void *data)
{
        struct igc_adapter *adapter = data;
        struct igc_hw *hw = &adapter->hw;
        u32 icr = rd32(IGC_ICR);

        /* reading ICR causes bit 31 of EICR to be cleared */
        if (icr & IGC_ICR_DRSTA)
                schedule_work(&adapter->reset_task);

        if (icr & IGC_ICR_DOUTSYNC) {
                /* HW is reporting DMA is out of sync */
                adapter->stats.doosync++;
        }

        if (icr & IGC_ICR_LSC) {
                hw->mac.get_link_status = 1;
                /* guard against interrupt when we're going down */
                if (!test_bit(__IGC_DOWN, &adapter->state))
                        mod_timer(&adapter->watchdog_timer, jiffies + 1);
        }

        wr32(IGC_EIMS, adapter->eims_other);

        return IRQ_HANDLED;
}

/**
 * igc_write_ivar - configure ivar for given MSI-X vector
 * @hw: pointer to the HW structure
 * @msix_vector: vector number we are allocating to a given ring
 * @index: row index of IVAR register to write within IVAR table
 * @offset: column offset of in IVAR, should be multiple of 8
 *
 * The IVAR table consists of 2 columns,
 * each containing an cause allocation for an Rx and Tx ring, and a
 * variable number of rows depending on the number of queues supported.
 */
static void igc_write_ivar(struct igc_hw *hw, int msix_vector,
                           int index, int offset)
{
        u32 ivar = array_rd32(IGC_IVAR0, index);

        /* clear any bits that are currently set */
        ivar &= ~((u32)0xFF << offset);

        /* write vector and valid bit */
        ivar |= (msix_vector | IGC_IVAR_VALID) << offset;

        array_wr32(IGC_IVAR0, index, ivar);
}

static void igc_assign_vector(struct igc_q_vector *q_vector, int msix_vector)
{
        struct igc_adapter *adapter = q_vector->adapter;
        struct igc_hw *hw = &adapter->hw;
        int rx_queue = IGC_N0_QUEUE;
        int tx_queue = IGC_N0_QUEUE;

        if (q_vector->rx.ring)
                rx_queue = q_vector->rx.ring->reg_idx;
        if (q_vector->tx.ring)
                tx_queue = q_vector->tx.ring->reg_idx;

        switch (hw->mac.type) {
        case igc_i225:
                if (rx_queue > IGC_N0_QUEUE)
                        igc_write_ivar(hw, msix_vector,
                                       rx_queue >> 1,
                                       (rx_queue & 0x1) << 4);
                if (tx_queue > IGC_N0_QUEUE)
                        igc_write_ivar(hw, msix_vector,
                                       tx_queue >> 1,
                                       ((tx_queue & 0x1) << 4) + 8);
                q_vector->eims_value = BIT(msix_vector);
                break;
        default:
                WARN_ONCE(hw->mac.type != igc_i225, "Wrong MAC type\n");
                break;
        }

        /* add q_vector eims value to global eims_enable_mask */
        adapter->eims_enable_mask |= q_vector->eims_value;

        /* configure q_vector to set itr on first interrupt */
        q_vector->set_itr = 1;
}

/**
 * igc_configure_msix - Configure MSI-X hardware
 * @adapter: Pointer to adapter structure
 *
 * igc_configure_msix sets up the hardware to properly
 * generate MSI-X interrupts.
 */
static void igc_configure_msix(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        int i, vector = 0;
        u32 tmp;

        adapter->eims_enable_mask = 0;

        /* set vector for other causes, i.e. link changes */
        switch (hw->mac.type) {
        case igc_i225:
                /* Turn on MSI-X capability first, or our settings
                 * won't stick.  And it will take days to debug.
                 */
                wr32(IGC_GPIE, IGC_GPIE_MSIX_MODE |
                     IGC_GPIE_PBA | IGC_GPIE_EIAME |
                     IGC_GPIE_NSICR);

                /* enable msix_other interrupt */
                adapter->eims_other = BIT(vector);
                tmp = (vector++ | IGC_IVAR_VALID) << 8;

                wr32(IGC_IVAR_MISC, tmp);
                break;
        default:
                /* do nothing, since nothing else supports MSI-X */
                break;
        } /* switch (hw->mac.type) */

        adapter->eims_enable_mask |= adapter->eims_other;

        for (i = 0; i < adapter->num_q_vectors; i++)
                igc_assign_vector(adapter->q_vector[i], vector++);

        wrfl();
}

static irqreturn_t igc_msix_ring(int irq, void *data)
{
        struct igc_q_vector *q_vector = data;

        /* Write the ITR value calculated from the previous interrupt. */
        igc_write_itr(q_vector);

        napi_schedule(&q_vector->napi);

        return IRQ_HANDLED;
}

/**
 * igc_request_msix - Initialize MSI-X interrupts
 * @adapter: Pointer to adapter structure
 *
 * igc_request_msix allocates MSI-X vectors and requests interrupts from the
 * kernel.
 */
static int igc_request_msix(struct igc_adapter *adapter)
{
        int i = 0, err = 0, vector = 0, free_vector = 0;
        struct net_device *netdev = adapter->netdev;

        err = request_irq(adapter->msix_entries[vector].vector,
                          &igc_msix_other, 0, netdev->name, adapter);
        if (err)
                goto err_out;

        for (i = 0; i < adapter->num_q_vectors; i++) {
                struct igc_q_vector *q_vector = adapter->q_vector[i];

                vector++;

                q_vector->itr_register = adapter->io_addr + IGC_EITR(vector);

                if (q_vector->rx.ring && q_vector->tx.ring)
                        sprintf(q_vector->name, "%s-TxRx-%u", netdev->name,
                                q_vector->rx.ring->queue_index);
                else if (q_vector->tx.ring)
                        sprintf(q_vector->name, "%s-tx-%u", netdev->name,
                                q_vector->tx.ring->queue_index);
                else if (q_vector->rx.ring)
                        sprintf(q_vector->name, "%s-rx-%u", netdev->name,
                                q_vector->rx.ring->queue_index);
                else
                        sprintf(q_vector->name, "%s-unused", netdev->name);

                err = request_irq(adapter->msix_entries[vector].vector,
                                  igc_msix_ring, 0, q_vector->name,
                                  q_vector);
                if (err)
                        goto err_free;
        }

        igc_configure_msix(adapter);
        return 0;

err_free:
        /* free already assigned IRQs */
        free_irq(adapter->msix_entries[free_vector++].vector, adapter);

        vector--;
        for (i = 0; i < vector; i++) {
                free_irq(adapter->msix_entries[free_vector++].vector,
                         adapter->q_vector[i]);
        }
err_out:
        return err;
}

/**
 * igc_reset_q_vector - Reset config for interrupt vector
 * @adapter: board private structure to initialize
 * @v_idx: Index of vector to be reset
 *
 * If NAPI is enabled it will delete any references to the
 * NAPI struct. This is preparation for igc_free_q_vector.
 */
static void igc_reset_q_vector(struct igc_adapter *adapter, int v_idx)
{
        struct igc_q_vector *q_vector = adapter->q_vector[v_idx];

        /* if we're coming from igc_set_interrupt_capability, the vectors are
         * not yet allocated
         */
        if (!q_vector)
                return;

        if (q_vector->tx.ring)
                adapter->tx_ring[q_vector->tx.ring->queue_index] = NULL;

        if (q_vector->rx.ring)
                adapter->rx_ring[q_vector->rx.ring->queue_index] = NULL;

        netif_napi_del(&q_vector->napi);
}

static void igc_reset_interrupt_capability(struct igc_adapter *adapter)
{
        int v_idx = adapter->num_q_vectors;

        if (adapter->msix_entries) {
                pci_disable_msix(adapter->pdev);
                kfree(adapter->msix_entries);
                adapter->msix_entries = NULL;
        } else if (adapter->flags & IGC_FLAG_HAS_MSI) {
                pci_disable_msi(adapter->pdev);
        }

        while (v_idx--)
                igc_reset_q_vector(adapter, v_idx);
}

/**
 * igc_clear_interrupt_scheme - reset the device to a state of no interrupts
 * @adapter: Pointer to adapter structure
 *
 * This function resets the device so that it has 0 rx queues, tx queues, and
 * MSI-X interrupts allocated.
 */
static void igc_clear_interrupt_scheme(struct igc_adapter *adapter)
{
        igc_free_q_vectors(adapter);
        igc_reset_interrupt_capability(adapter);
}

/**
 * igc_free_q_vectors - Free memory allocated for interrupt vectors
 * @adapter: board private structure to initialize
 *
 * This function frees the memory allocated to the q_vectors.  In addition if
 * NAPI is enabled it will delete any references to the NAPI struct prior
 * to freeing the q_vector.
 */
static void igc_free_q_vectors(struct igc_adapter *adapter)
{
        int v_idx = adapter->num_q_vectors;

        adapter->num_tx_queues = 0;
        adapter->num_rx_queues = 0;
        adapter->num_q_vectors = 0;

        while (v_idx--) {
                igc_reset_q_vector(adapter, v_idx);
                igc_free_q_vector(adapter, v_idx);
        }
}

/**
 * igc_free_q_vector - Free memory allocated for specific interrupt vector
 * @adapter: board private structure to initialize
 * @v_idx: Index of vector to be freed
 *
 * This function frees the memory allocated to the q_vector.
 */
static void igc_free_q_vector(struct igc_adapter *adapter, int v_idx)
{
        struct igc_q_vector *q_vector = adapter->q_vector[v_idx];

        adapter->q_vector[v_idx] = NULL;

        /* igc_get_stats64() might access the rings on this vector,
         * we must wait a grace period before freeing it.
         */
        if (q_vector)
                kfree_rcu(q_vector, rcu);
}

/* Need to wait a few seconds after link up to get diagnostic information from
 * the phy
 */
static void igc_update_phy_info(struct timer_list *t)
{
        struct igc_adapter *adapter = from_timer(adapter, t, phy_info_timer);

        igc_get_phy_info(&adapter->hw);
}

/**
 * igc_has_link - check shared code for link and determine up/down
 * @adapter: pointer to driver private info
 */
bool igc_has_link(struct igc_adapter *adapter)
{
        struct igc_hw *hw = &adapter->hw;
        bool link_active = false;

        /* get_link_status is set on LSC (link status) interrupt or
         * rx sequence error interrupt.  get_link_status will stay
         * false until the igc_check_for_link establishes link
         * for copper adapters ONLY
         */
        switch (hw->phy.media_type) {
        case igc_media_type_copper:
                if (!hw->mac.get_link_status)
                        return true;
                hw->mac.ops.check_for_link(hw);
                link_active = !hw->mac.get_link_status;
                break;
        default:
        case igc_media_type_unknown:
                break;
        }

        if (hw->mac.type == igc_i225 &&
            hw->phy.id == I225_I_PHY_ID) {
                if (!netif_carrier_ok(adapter->netdev)) {
                        adapter->flags &= ~IGC_FLAG_NEED_LINK_UPDATE;
                } else if (!(adapter->flags & IGC_FLAG_NEED_LINK_UPDATE)) {
                        adapter->flags |= IGC_FLAG_NEED_LINK_UPDATE;
                        adapter->link_check_timeout = jiffies;
                }
        }

        return link_active;
}

/**
 * igc_watchdog - Timer Call-back
 * @data: pointer to adapter cast into an unsigned long
 */
static void igc_watchdog(struct timer_list *t)
{
        struct igc_adapter *adapter = from_timer(adapter, t, watchdog_timer);
        /* Do the rest outside of interrupt context */
        schedule_work(&adapter->watchdog_task);
}

static void igc_watchdog_task(struct work_struct *work)
{
        struct igc_adapter *adapter = container_of(work,
                                                   struct igc_adapter,
                                                   watchdog_task);
        struct net_device *netdev = adapter->netdev;
        struct igc_hw *hw = &adapter->hw;
        struct igc_phy_info *phy = &hw->phy;
        u16 phy_data, retry_count = 20;
        u32 connsw;
        u32 link;
        int i;

        link = igc_has_link(adapter);

        if (adapter->flags & IGC_FLAG_NEED_LINK_UPDATE) {
                if (time_after(jiffies, (adapter->link_check_timeout + HZ)))
                        adapter->flags &= ~IGC_FLAG_NEED_LINK_UPDATE;
                else
                        link = false;
        }

        /* Force link down if we have fiber to swap to */
        if (adapter->flags & IGC_FLAG_MAS_ENABLE) {
                if (hw->phy.media_type == igc_media_type_copper) {
                        connsw = rd32(IGC_CONNSW);
                        if (!(connsw & IGC_CONNSW_AUTOSENSE_EN))
                                link = 0;
                }
        }
        if (link) {
                if (!netif_carrier_ok(netdev)) {
                        u32 ctrl;

                        hw->mac.ops.get_speed_and_duplex(hw,
                                                         &adapter->link_speed,
                                                         &adapter->link_duplex);

                        ctrl = rd32(IGC_CTRL);
                        /* Link status message must follow this format */
                        netdev_info(netdev,
                                    "igc: %s NIC Link is Up %d Mbps %s Duplex, Flow Control: %s\n",
                                    netdev->name,
                                    adapter->link_speed,
                                    adapter->link_duplex == FULL_DUPLEX ?
                                    "Full" : "Half",
                                    (ctrl & IGC_CTRL_TFCE) &&
                                    (ctrl & IGC_CTRL_RFCE) ? "RX/TX" :
                                    (ctrl & IGC_CTRL_RFCE) ?  "RX" :
                                    (ctrl & IGC_CTRL_TFCE) ?  "TX" : "None");

                        /* check if SmartSpeed worked */
                        igc_check_downshift(hw);
                        if (phy->speed_downgraded)
                                netdev_warn(netdev, "Link Speed was downgraded by SmartSpeed\n");

                        /* adjust timeout factor according to speed/duplex */
                        adapter->tx_timeout_factor = 1;
                        switch (adapter->link_speed) {
                        case SPEED_10:
                                adapter->tx_timeout_factor = 14;
                                break;
                        case SPEED_100:
                                /* maybe add some timeout factor ? */
                                break;
                        }

                        if (adapter->link_speed != SPEED_1000)
                                goto no_wait;

                        /* wait for Remote receiver status OK */
retry_read_status:
                        if (!igc_read_phy_reg(hw, PHY_1000T_STATUS,
                                              &phy_data)) {
                                if (!(phy_data & SR_1000T_REMOTE_RX_STATUS) &&
                                    retry_count) {
                                        msleep(100);
                                        retry_count--;
                                        goto retry_read_status;
                                } else if (!retry_count) {
                                        dev_err(&adapter->pdev->dev, "exceed max 2 second\n");
                                }
                        } else {
                                dev_err(&adapter->pdev->dev, "read 1000Base-T Status Reg\n");
                        }
no_wait:
                        netif_carrier_on(netdev);

                        /* link state has changed, schedule phy info update */
                        if (!test_bit(__IGC_DOWN, &adapter->state))
                                mod_timer(&adapter->phy_info_timer,
                                          round_jiffies(jiffies + 2 * HZ));
                }
        } else {
                if (netif_carrier_ok(netdev)) {
                        adapter->link_speed = 0;
                        adapter->link_duplex = 0;

                        /* Links status message must follow this format */
                        netdev_info(netdev, "igc: %s NIC Link is Down\n",
                                    netdev->name);
                        netif_carrier_off(netdev);

                        /* link state has changed, schedule phy info update */
                        if (!test_bit(__IGC_DOWN, &adapter->state))
                                mod_timer(&adapter->phy_info_timer,
                                          round_jiffies(jiffies + 2 * HZ));

                        /* link is down, time to check for alternate media */
                        if (adapter->flags & IGC_FLAG_MAS_ENABLE) {
                                if (adapter->flags & IGC_FLAG_MEDIA_RESET) {
                                        schedule_work(&adapter->reset_task);
                                        /* return immediately */
                                        return;
                                }
                        }

                /* also check for alternate media here */
                } else if (!netif_carrier_ok(netdev) &&
                           (adapter->flags & IGC_FLAG_MAS_ENABLE)) {
                        if (adapter->flags & IGC_FLAG_MEDIA_RESET) {
                                schedule_work(&adapter->reset_task);
                                /* return immediately */
                                return;
                        }
                }
        }

        spin_lock(&adapter->stats64_lock);
        igc_update_stats(adapter);
        spin_unlock(&adapter->stats64_lock);

        for (i = 0; i < adapter->num_tx_queues; i++) {
                struct igc_ring *tx_ring = adapter->tx_ring[i];

                if (!netif_carrier_ok(netdev)) {
                        /* We've lost link, so the controller stops DMA,
                         * but we've got queued Tx work that's never going
                         * to get done, so reset controller to flush Tx.
                         * (Do the reset outside of interrupt context).
                         */
                        if (igc_desc_unused(tx_ring) + 1 < tx_ring->count) {
                                adapter->tx_timeout_count++;
                                schedule_work(&adapter->reset_task);
                                /* return immediately since reset is imminent */
                                return;
                        }
                }

                /* Force detection of hung controller every watchdog period */
                set_bit(IGC_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags);
        }

        /* Cause software interrupt to ensure Rx ring is cleaned */
        if (adapter->flags & IGC_FLAG_HAS_MSIX) {
                u32 eics = 0;

                for (i = 0; i < adapter->num_q_vectors; i++)
                        eics |= adapter->q_vector[i]->eims_value;
                wr32(IGC_EICS, eics);
        } else {
                wr32(IGC_ICS, IGC_ICS_RXDMT0);
        }

        /* Reset the timer */
        if (!test_bit(__IGC_DOWN, &adapter->state)) {
                if (adapter->flags & IGC_FLAG_NEED_LINK_UPDATE)
                        mod_timer(&adapter->watchdog_timer,
                                  round_jiffies(jiffies +  HZ));
                else
                        mod_timer(&adapter->watchdog_timer,
                                  round_jiffies(jiffies + 2 * HZ));
        }
}

/**
 * igc_update_ring_itr - update the dynamic ITR value based on packet size
 * @q_vector: pointer to q_vector
 *
 * Stores a new ITR value based on strictly on packet size.  This
 * algorithm is less sophisticated than that used in igc_update_itr,
 * due to the difficulty of synchronizing statistics across multiple
 * receive rings.  The divisors and thresholds used by this function
 * were determined based on theoretical maximum wire speed and testing
 * data, in order to minimize response time while increasing bulk
 * throughput.
 * NOTE: This function is called only when operating in a multiqueue
 * receive environment.
 */
static void igc_update_ring_itr(struct igc_q_vector *q_vector)
{
        struct igc_adapter *adapter = q_vector->adapter;
        int new_val = q_vector->itr_val;
        int avg_wire_size = 0;
        unsigned int packets;

        /* For non-gigabit speeds, just fix the interrupt rate at 4000