linux-vybrid_public/drivers/net/ixgbe/ixgbe_main.c

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

  Intel 10 Gigabit PCI Express Linux driver
  Copyright(c) 1999 - 2007 Intel Corporation.

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  more details.

  You should have received a copy of the GNU General Public License along with
  this program; if not, write to the Free Software Foundation, Inc.,
  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Contact Information:
  Linux NICS <linux.nics@intel.com>
  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

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

#include <linux/types.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/ipv6.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>

#include "ixgbe.h"
#include "ixgbe_common.h"

char ixgbe_driver_name[] = "ixgbe";
static const char ixgbe_driver_string[] =
	"Intel(R) 10 Gigabit PCI Express Network Driver";

#define DRV_VERSION "1.3.18-k2"
const char ixgbe_driver_version[] = DRV_VERSION;
static const char ixgbe_copyright[] =
	 "Copyright (c) 1999-2007 Intel Corporation.";

static const struct ixgbe_info *ixgbe_info_tbl[] = {
	[board_82598]			= &ixgbe_82598_info,
};

/* ixgbe_pci_tbl - PCI Device ID Table
 *
 * Wildcard entries (PCI_ANY_ID) should come last
 * Last entry must be all 0s
 *
 * { Vendor ID, Device ID, SubVendor ID, SubDevice ID,
 *   Class, Class Mask, private data (not used) }
 */
static struct pci_device_id ixgbe_pci_tbl[] = {
	{PCI_VDEVICE(INTEL, IXGBE_DEV_ID_82598AF_DUAL_PORT),
	 board_82598 },
	{PCI_VDEVICE(INTEL, IXGBE_DEV_ID_82598AF_SINGLE_PORT),
	 board_82598 },
	{PCI_VDEVICE(INTEL, IXGBE_DEV_ID_82598AT_DUAL_PORT),
	 board_82598 },
	{PCI_VDEVICE(INTEL, IXGBE_DEV_ID_82598EB_CX4),
	 board_82598 },

	/* required last entry */
	{0, }
};
MODULE_DEVICE_TABLE(pci, ixgbe_pci_tbl);

#ifdef CONFIG_DCA
static int ixgbe_notify_dca(struct notifier_block *, unsigned long event,
			    void *p);
static struct notifier_block dca_notifier = {
	.notifier_call = ixgbe_notify_dca,
	.next          = NULL,
	.priority      = 0
};
#endif

MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
MODULE_DESCRIPTION("Intel(R) 10 Gigabit PCI Express Network Driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

#define DEFAULT_DEBUG_LEVEL_SHIFT 3

static void ixgbe_release_hw_control(struct ixgbe_adapter *adapter)
{
	u32 ctrl_ext;

	/* Let firmware take over control of h/w */
	ctrl_ext = IXGBE_READ_REG(&adapter->hw, IXGBE_CTRL_EXT);
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_CTRL_EXT,
			ctrl_ext & ~IXGBE_CTRL_EXT_DRV_LOAD);
}

static void ixgbe_get_hw_control(struct ixgbe_adapter *adapter)
{
	u32 ctrl_ext;

	/* Let firmware know the driver has taken over */
	ctrl_ext = IXGBE_READ_REG(&adapter->hw, IXGBE_CTRL_EXT);
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_CTRL_EXT,
			ctrl_ext | IXGBE_CTRL_EXT_DRV_LOAD);
}

#ifdef DEBUG
/**
 * ixgbe_get_hw_dev_name - return device name string
 * used by hardware layer to print debugging information
 **/
char *ixgbe_get_hw_dev_name(struct ixgbe_hw *hw)
{
	struct ixgbe_adapter *adapter = hw->back;
	struct net_device *netdev = adapter->netdev;
	return netdev->name;
}
#endif

static void ixgbe_set_ivar(struct ixgbe_adapter *adapter, u16 int_alloc_entry,
			   u8 msix_vector)
{
	u32 ivar, index;

	msix_vector |= IXGBE_IVAR_ALLOC_VAL;
	index = (int_alloc_entry >> 2) & 0x1F;
	ivar = IXGBE_READ_REG(&adapter->hw, IXGBE_IVAR(index));
	ivar &= ~(0xFF << (8 * (int_alloc_entry & 0x3)));
	ivar |= (msix_vector << (8 * (int_alloc_entry & 0x3)));
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_IVAR(index), ivar);
}

static void ixgbe_unmap_and_free_tx_resource(struct ixgbe_adapter *adapter,
					     struct ixgbe_tx_buffer
					     *tx_buffer_info)
{
	if (tx_buffer_info->dma) {
		pci_unmap_page(adapter->pdev,
			       tx_buffer_info->dma,
			       tx_buffer_info->length, PCI_DMA_TODEVICE);
		tx_buffer_info->dma = 0;
	}
	if (tx_buffer_info->skb) {
		dev_kfree_skb_any(tx_buffer_info->skb);
		tx_buffer_info->skb = NULL;
	}
	/* tx_buffer_info must be completely set up in the transmit path */
}

static inline bool ixgbe_check_tx_hang(struct ixgbe_adapter *adapter,
				       struct ixgbe_ring *tx_ring,
				       unsigned int eop,
				       union ixgbe_adv_tx_desc *eop_desc)
{
	/* Detect a transmit hang in hardware, this serializes the
	 * check with the clearing of time_stamp and movement of i */
	adapter->detect_tx_hung = false;
	if (tx_ring->tx_buffer_info[eop].dma &&
	    time_after(jiffies, tx_ring->tx_buffer_info[eop].time_stamp + HZ) &&
	    !(IXGBE_READ_REG(&adapter->hw, IXGBE_TFCS) & IXGBE_TFCS_TXOFF)) {
		/* detected Tx unit hang */
		DPRINTK(DRV, ERR, "Detected Tx Unit Hang\n"
			"  TDH                  <%x>\n"
			"  TDT                  <%x>\n"
			"  next_to_use          <%x>\n"
			"  next_to_clean        <%x>\n"
			"tx_buffer_info[next_to_clean]\n"
			"  time_stamp           <%lx>\n"
			"  next_to_watch        <%x>\n"
			"  jiffies              <%lx>\n"
			"  next_to_watch.status <%x>\n",
			readl(adapter->hw.hw_addr + tx_ring->head),
			readl(adapter->hw.hw_addr + tx_ring->tail),
			tx_ring->next_to_use,
			tx_ring->next_to_clean,
			tx_ring->tx_buffer_info[eop].time_stamp,
			eop, jiffies, eop_desc->wb.status);
		return true;
	}

	return false;
}

#define IXGBE_MAX_TXD_PWR	14
#define IXGBE_MAX_DATA_PER_TXD	(1 << IXGBE_MAX_TXD_PWR)

/* Tx Descriptors needed, worst case */
#define TXD_USE_COUNT(S) (((S) >> IXGBE_MAX_TXD_PWR) + \
			 (((S) & (IXGBE_MAX_DATA_PER_TXD - 1)) ? 1 : 0))
#define DESC_NEEDED (TXD_USE_COUNT(IXGBE_MAX_DATA_PER_TXD) /* skb->data */ + \
	MAX_SKB_FRAGS * TXD_USE_COUNT(PAGE_SIZE) + 1)	/* for context */

/**
 * ixgbe_clean_tx_irq - Reclaim resources after transmit completes
 * @adapter: board private structure
 **/
static bool ixgbe_clean_tx_irq(struct ixgbe_adapter *adapter,
				    struct ixgbe_ring *tx_ring)
{
	struct net_device *netdev = adapter->netdev;
	union ixgbe_adv_tx_desc *tx_desc, *eop_desc;
	struct ixgbe_tx_buffer *tx_buffer_info;
	unsigned int i, eop;
	bool cleaned = false;
	unsigned int total_tx_bytes = 0, total_tx_packets = 0;

	i = tx_ring->next_to_clean;
	eop = tx_ring->tx_buffer_info[i].next_to_watch;
	eop_desc = IXGBE_TX_DESC_ADV(*tx_ring, eop);
	while (eop_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)) {
		cleaned = false;
		while (!cleaned) {
			tx_desc = IXGBE_TX_DESC_ADV(*tx_ring, i);
			tx_buffer_info = &tx_ring->tx_buffer_info[i];
			cleaned = (i == eop);

			tx_ring->stats.bytes += tx_buffer_info->length;
			if (cleaned) {
				struct sk_buff *skb = tx_buffer_info->skb;
				unsigned int segs, bytecount;
				segs = skb_shinfo(skb)->gso_segs ?: 1;
				/* multiply data chunks by size of headers */
				bytecount = ((segs - 1) * skb_headlen(skb)) +
					    skb->len;
				total_tx_packets += segs;
				total_tx_bytes += bytecount;
			}
			ixgbe_unmap_and_free_tx_resource(adapter,
							 tx_buffer_info);
			tx_desc->wb.status = 0;

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

		tx_ring->stats.packets++;

		eop = tx_ring->tx_buffer_info[i].next_to_watch;
		eop_desc = IXGBE_TX_DESC_ADV(*tx_ring, eop);

		/* weight of a sort for tx, avoid endless transmit cleanup */
		if (total_tx_packets >= tx_ring->work_limit)
			break;
	}

	tx_ring->next_to_clean = i;

#define TX_WAKE_THRESHOLD (DESC_NEEDED * 2)
	if (total_tx_packets && netif_carrier_ok(netdev) &&
	    (IXGBE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD)) {
		/* Make sure that anybody stopping the queue after this
		 * sees the new next_to_clean.
		 */
		smp_mb();
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
		if (__netif_subqueue_stopped(netdev, tx_ring->queue_index) &&
		    !test_bit(__IXGBE_DOWN, &adapter->state)) {
			netif_wake_subqueue(netdev, tx_ring->queue_index);
			adapter->restart_queue++;
		}
#else
		if (netif_queue_stopped(netdev) &&
		    !test_bit(__IXGBE_DOWN, &adapter->state)) {
			netif_wake_queue(netdev);
			adapter->restart_queue++;
		}
#endif
	}

	if (adapter->detect_tx_hung)
		if (ixgbe_check_tx_hang(adapter, tx_ring, eop, eop_desc))
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
			netif_stop_subqueue(netdev, tx_ring->queue_index);
#else
			netif_stop_queue(netdev);
#endif

	if (total_tx_packets >= tx_ring->work_limit)
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, tx_ring->eims_value);

	tx_ring->total_bytes += total_tx_bytes;
	tx_ring->total_packets += total_tx_packets;
	adapter->net_stats.tx_bytes += total_tx_bytes;
	adapter->net_stats.tx_packets += total_tx_packets;
	cleaned = total_tx_packets ? true : false;
	return cleaned;
}

#ifdef CONFIG_DCA
static void ixgbe_update_rx_dca(struct ixgbe_adapter *adapter,
				struct ixgbe_ring *rxr)
{
	u32 rxctrl;
	int cpu = get_cpu();
	int q = rxr - adapter->rx_ring;

	if (rxr->cpu != cpu) {
		rxctrl = IXGBE_READ_REG(&adapter->hw, IXGBE_DCA_RXCTRL(q));
		rxctrl &= ~IXGBE_DCA_RXCTRL_CPUID_MASK;
		rxctrl |= dca_get_tag(cpu);
		rxctrl |= IXGBE_DCA_RXCTRL_DESC_DCA_EN;
		rxctrl |= IXGBE_DCA_RXCTRL_HEAD_DCA_EN;
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_DCA_RXCTRL(q), rxctrl);
		rxr->cpu = cpu;
	}
	put_cpu();
}

static void ixgbe_update_tx_dca(struct ixgbe_adapter *adapter,
				struct ixgbe_ring *txr)
{
	u32 txctrl;
	int cpu = get_cpu();
	int q = txr - adapter->tx_ring;

	if (txr->cpu != cpu) {
		txctrl = IXGBE_READ_REG(&adapter->hw, IXGBE_DCA_TXCTRL(q));
		txctrl &= ~IXGBE_DCA_TXCTRL_CPUID_MASK;
		txctrl |= dca_get_tag(cpu);
		txctrl |= IXGBE_DCA_TXCTRL_DESC_DCA_EN;
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_DCA_TXCTRL(q), txctrl);
		txr->cpu = cpu;
	}
	put_cpu();
}

static void ixgbe_setup_dca(struct ixgbe_adapter *adapter)
{
	int i;

	if (!(adapter->flags & IXGBE_FLAG_DCA_ENABLED))
		return;

	for (i = 0; i < adapter->num_tx_queues; i++) {
		adapter->tx_ring[i].cpu = -1;
		ixgbe_update_tx_dca(adapter, &adapter->tx_ring[i]);
	}
	for (i = 0; i < adapter->num_rx_queues; i++) {
		adapter->rx_ring[i].cpu = -1;
		ixgbe_update_rx_dca(adapter, &adapter->rx_ring[i]);
	}
}

static int __ixgbe_notify_dca(struct device *dev, void *data)
{
	struct net_device *netdev = dev_get_drvdata(dev);
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	unsigned long event = *(unsigned long *)data;

	switch (event) {
	case DCA_PROVIDER_ADD:
		adapter->flags |= IXGBE_FLAG_DCA_ENABLED;
		/* Always use CB2 mode, difference is masked
		 * in the CB driver. */
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_DCA_CTRL, 2);
		if (dca_add_requester(dev) == 0) {
			ixgbe_setup_dca(adapter);
			break;
		}
		/* Fall Through since DCA is disabled. */
	case DCA_PROVIDER_REMOVE:
		if (adapter->flags & IXGBE_FLAG_DCA_ENABLED) {
			dca_remove_requester(dev);
			adapter->flags &= ~IXGBE_FLAG_DCA_ENABLED;
			IXGBE_WRITE_REG(&adapter->hw, IXGBE_DCA_CTRL, 1);
		}
		break;
	}

	return 0;
}

#endif /* CONFIG_DCA */
/**
 * ixgbe_receive_skb - Send a completed packet up the stack
 * @adapter: board private structure
 * @skb: packet to send up
 * @is_vlan: packet has a VLAN tag
 * @tag: VLAN tag from descriptor
 **/
static void ixgbe_receive_skb(struct ixgbe_adapter *adapter,
			      struct sk_buff *skb, bool is_vlan,
			      u16 tag)
{
	if (!(adapter->flags & IXGBE_FLAG_IN_NETPOLL)) {
		if (adapter->vlgrp && is_vlan)
			vlan_hwaccel_receive_skb(skb, adapter->vlgrp, tag);
		else
			netif_receive_skb(skb);
	} else {

		if (adapter->vlgrp && is_vlan)
			vlan_hwaccel_rx(skb, adapter->vlgrp, tag);
		else
			netif_rx(skb);
	}
}

/**
 * ixgbe_rx_checksum - indicate in skb if hw indicated a good cksum
 * @adapter: address of board private structure
 * @status_err: hardware indication of status of receive
 * @skb: skb currently being received and modified
 **/
static inline void ixgbe_rx_checksum(struct ixgbe_adapter *adapter,
					 u32 status_err,
					 struct sk_buff *skb)
{
	skb->ip_summed = CHECKSUM_NONE;

	/* Ignore Checksum bit is set, or rx csum disabled */
	if ((status_err & IXGBE_RXD_STAT_IXSM) ||
	    !(adapter->flags & IXGBE_FLAG_RX_CSUM_ENABLED))
		return;

	/* if IP and error */
	if ((status_err & IXGBE_RXD_STAT_IPCS) &&
	    (status_err & IXGBE_RXDADV_ERR_IPE)) {
		adapter->hw_csum_rx_error++;
		return;
	}

	if (!(status_err & IXGBE_RXD_STAT_L4CS))
		return;

	if (status_err & IXGBE_RXDADV_ERR_TCPE) {
		adapter->hw_csum_rx_error++;
		return;
	}

	/* It must be a TCP or UDP packet with a valid checksum */
	skb->ip_summed = CHECKSUM_UNNECESSARY;
	adapter->hw_csum_rx_good++;
}

/**
 * ixgbe_alloc_rx_buffers - Replace used receive buffers; packet split
 * @adapter: address of board private structure
 **/
static void ixgbe_alloc_rx_buffers(struct ixgbe_adapter *adapter,
				       struct ixgbe_ring *rx_ring,
				       int cleaned_count)
{
	struct net_device *netdev = adapter->netdev;
	struct pci_dev *pdev = adapter->pdev;
	union ixgbe_adv_rx_desc *rx_desc;
	struct ixgbe_rx_buffer *rx_buffer_info;
	struct sk_buff *skb;
	unsigned int i;
	unsigned int bufsz = adapter->rx_buf_len + NET_IP_ALIGN;

	i = rx_ring->next_to_use;
	rx_buffer_info = &rx_ring->rx_buffer_info[i];

	while (cleaned_count--) {
		rx_desc = IXGBE_RX_DESC_ADV(*rx_ring, i);

		if (!rx_buffer_info->page &&
				(adapter->flags & IXGBE_FLAG_RX_PS_ENABLED)) {
			rx_buffer_info->page = alloc_page(GFP_ATOMIC);
			if (!rx_buffer_info->page) {
				adapter->alloc_rx_page_failed++;
				goto no_buffers;
			}
			rx_buffer_info->page_dma =
			    pci_map_page(pdev, rx_buffer_info->page,
					 0, PAGE_SIZE, PCI_DMA_FROMDEVICE);
		}

		if (!rx_buffer_info->skb) {
			skb = netdev_alloc_skb(netdev, bufsz);

			if (!skb) {
				adapter->alloc_rx_buff_failed++;
				goto no_buffers;
			}

			/*
			 * Make buffer alignment 2 beyond a 16 byte boundary
			 * this will result in a 16 byte aligned IP header after
			 * the 14 byte MAC header is removed
			 */
			skb_reserve(skb, NET_IP_ALIGN);

			rx_buffer_info->skb = skb;
			rx_buffer_info->dma = pci_map_single(pdev, skb->data,
							  bufsz,
							  PCI_DMA_FROMDEVICE);
		}
		/* Refresh the desc even if buffer_addrs didn't change because
		 * each write-back erases this info. */
		if (adapter->flags & IXGBE_FLAG_RX_PS_ENABLED) {
			rx_desc->read.pkt_addr =
			    cpu_to_le64(rx_buffer_info->page_dma);
			rx_desc->read.hdr_addr =
					cpu_to_le64(rx_buffer_info->dma);
		} else {
			rx_desc->read.pkt_addr =
					cpu_to_le64(rx_buffer_info->dma);
		}

		i++;
		if (i == rx_ring->count)
			i = 0;
		rx_buffer_info = &rx_ring->rx_buffer_info[i];
	}
no_buffers:
	if (rx_ring->next_to_use != i) {
		rx_ring->next_to_use = i;
		if (i-- == 0)
			i = (rx_ring->count - 1);

		/*
		 * 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, adapter->hw.hw_addr + rx_ring->tail);
	}
}

static bool ixgbe_clean_rx_irq(struct ixgbe_adapter *adapter,
			       struct ixgbe_ring *rx_ring,
			       int *work_done, int work_to_do)
{
	struct net_device *netdev = adapter->netdev;
	struct pci_dev *pdev = adapter->pdev;
	union ixgbe_adv_rx_desc *rx_desc, *next_rxd;
	struct ixgbe_rx_buffer *rx_buffer_info, *next_buffer;
	struct sk_buff *skb;
	unsigned int i;
	u32 upper_len, len, staterr;
	u16 hdr_info, vlan_tag;
	bool is_vlan, cleaned = false;
	int cleaned_count = 0;
	unsigned int total_rx_bytes = 0, total_rx_packets = 0;

	i = rx_ring->next_to_clean;
	upper_len = 0;
	rx_desc = IXGBE_RX_DESC_ADV(*rx_ring, i);
	staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
	rx_buffer_info = &rx_ring->rx_buffer_info[i];
	is_vlan = (staterr & IXGBE_RXD_STAT_VP);
	vlan_tag = le16_to_cpu(rx_desc->wb.upper.vlan);

	while (staterr & IXGBE_RXD_STAT_DD) {
		if (*work_done >= work_to_do)
			break;
		(*work_done)++;

		if (adapter->flags & IXGBE_FLAG_RX_PS_ENABLED) {
			hdr_info =
			    le16_to_cpu(rx_desc->wb.lower.lo_dword.hdr_info);
			len =
			    ((hdr_info & IXGBE_RXDADV_HDRBUFLEN_MASK) >>
			     IXGBE_RXDADV_HDRBUFLEN_SHIFT);
			if (hdr_info & IXGBE_RXDADV_SPH)
				adapter->rx_hdr_split++;
			if (len > IXGBE_RX_HDR_SIZE)
				len = IXGBE_RX_HDR_SIZE;
			upper_len = le16_to_cpu(rx_desc->wb.upper.length);
		} else
			len = le16_to_cpu(rx_desc->wb.upper.length);

		cleaned = true;
		skb = rx_buffer_info->skb;
		prefetch(skb->data - NET_IP_ALIGN);
		rx_buffer_info->skb = NULL;

		if (len && !skb_shinfo(skb)->nr_frags) {
			pci_unmap_single(pdev, rx_buffer_info->dma,
					 adapter->rx_buf_len + NET_IP_ALIGN,
					 PCI_DMA_FROMDEVICE);
			skb_put(skb, len);
		}

		if (upper_len) {
			pci_unmap_page(pdev, rx_buffer_info->page_dma,
				       PAGE_SIZE, PCI_DMA_FROMDEVICE);
			rx_buffer_info->page_dma = 0;
			skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags,
					   rx_buffer_info->page, 0, upper_len);
			rx_buffer_info->page = NULL;

			skb->len += upper_len;
			skb->data_len += upper_len;
			skb->truesize += upper_len;
		}

		i++;
		if (i == rx_ring->count)
			i = 0;
		next_buffer = &rx_ring->rx_buffer_info[i];

		next_rxd = IXGBE_RX_DESC_ADV(*rx_ring, i);
		prefetch(next_rxd);

		cleaned_count++;
		if (staterr & IXGBE_RXD_STAT_EOP) {
			rx_ring->stats.packets++;
			rx_ring->stats.bytes += skb->len;
		} else {
			rx_buffer_info->skb = next_buffer->skb;
			rx_buffer_info->dma = next_buffer->dma;
			next_buffer->skb = skb;
			adapter->non_eop_descs++;
			goto next_desc;
		}

		if (staterr & IXGBE_RXDADV_ERR_FRAME_ERR_MASK) {
			dev_kfree_skb_irq(skb);
			goto next_desc;
		}

		ixgbe_rx_checksum(adapter, staterr, skb);

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

		skb->protocol = eth_type_trans(skb, netdev);
		ixgbe_receive_skb(adapter, skb, is_vlan, vlan_tag);
		netdev->last_rx = jiffies;

next_desc:
		rx_desc->wb.upper.status_error = 0;

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

		/* use prefetched values */
		rx_desc = next_rxd;
		rx_buffer_info = next_buffer;

		staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
		is_vlan = (staterr & IXGBE_RXD_STAT_VP);
		vlan_tag = le16_to_cpu(rx_desc->wb.upper.vlan);
	}

	rx_ring->next_to_clean = i;
	cleaned_count = IXGBE_DESC_UNUSED(rx_ring);

	if (cleaned_count)
		ixgbe_alloc_rx_buffers(adapter, rx_ring, cleaned_count);

	adapter->net_stats.rx_bytes += total_rx_bytes;
	adapter->net_stats.rx_packets += total_rx_packets;

	rx_ring->total_packets += total_rx_packets;
	rx_ring->total_bytes += total_rx_bytes;
	adapter->net_stats.rx_bytes += total_rx_bytes;
	adapter->net_stats.rx_packets += total_rx_packets;

	return cleaned;
}

static int ixgbe_clean_rxonly(struct napi_struct *, int);
/**
 * ixgbe_configure_msix - Configure MSI-X hardware
 * @adapter: board private structure
 *
 * ixgbe_configure_msix sets up the hardware to properly generate MSI-X
 * interrupts.
 **/
static void ixgbe_configure_msix(struct ixgbe_adapter *adapter)
{
	struct ixgbe_q_vector *q_vector;
	int i, j, q_vectors, v_idx, r_idx;
	u32 mask;

	q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

	/* Populate the IVAR table and set the ITR values to the
	 * corresponding register.
	 */
	for (v_idx = 0; v_idx < q_vectors; v_idx++) {
		q_vector = &adapter->q_vector[v_idx];
		/* XXX for_each_bit(...) */
		r_idx = find_first_bit(q_vector->rxr_idx,
				      adapter->num_rx_queues);

		for (i = 0; i < q_vector->rxr_count; i++) {
			j = adapter->rx_ring[r_idx].reg_idx;
			ixgbe_set_ivar(adapter, IXGBE_IVAR_RX_QUEUE(j), v_idx);
			r_idx = find_next_bit(q_vector->rxr_idx,
					      adapter->num_rx_queues,
					      r_idx + 1);
		}
		r_idx = find_first_bit(q_vector->txr_idx,
				       adapter->num_tx_queues);

		for (i = 0; i < q_vector->txr_count; i++) {
			j = adapter->tx_ring[r_idx].reg_idx;
			ixgbe_set_ivar(adapter, IXGBE_IVAR_TX_QUEUE(j), v_idx);
			r_idx = find_next_bit(q_vector->txr_idx,
					      adapter->num_tx_queues,
					      r_idx + 1);
		}

		/* if this is a tx only vector use half the irq (tx) rate */
		if (q_vector->txr_count && !q_vector->rxr_count)
			q_vector->eitr = adapter->tx_eitr;
		else
			/* rx only or mixed */
			q_vector->eitr = adapter->rx_eitr;

		IXGBE_WRITE_REG(&adapter->hw, IXGBE_EITR(v_idx),
				EITR_INTS_PER_SEC_TO_REG(q_vector->eitr));
	}

	ixgbe_set_ivar(adapter, IXGBE_IVAR_OTHER_CAUSES_INDEX, v_idx);
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_EITR(v_idx), 1950);

	/* set up to autoclear timer, lsc, and the vectors */
	mask = IXGBE_EIMS_ENABLE_MASK;
	mask &= ~IXGBE_EIMS_OTHER;
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIAC, mask);
}

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

/**
 * ixgbe_update_itr - update the dynamic ITR value based on statistics
 * @adapter: pointer to adapter
 * @eitr: eitr setting (ints per sec) to give last timeslice
 * @itr_setting: current throttle rate in ints/second
 * @packets: the number of packets during this measurement interval
 * @bytes: the number of bytes during this measurement interval
 *
 *      Stores a new ITR value based on packets and byte
 *      counts during the last interrupt.  The advantage of per interrupt
 *      computation is faster updates and more accurate ITR for the current
 *      traffic pattern.  Constants in this function were computed
 *      based on theoretical maximum wire speed and thresholds were set based
 *      on testing data as well as attempting to minimize response time
 *      while increasing bulk throughput.
 *      this functionality is controlled by the InterruptThrottleRate module
 *      parameter (see ixgbe_param.c)
 **/
static u8 ixgbe_update_itr(struct ixgbe_adapter *adapter,
			   u32 eitr, u8 itr_setting,
			   int packets, int bytes)
{
	unsigned int retval = itr_setting;
	u32 timepassed_us;
	u64 bytes_perint;

	if (packets == 0)
		goto update_itr_done;


	/* simple throttlerate management
	 *    0-20MB/s lowest (100000 ints/s)
	 *   20-100MB/s low   (20000 ints/s)
	 *  100-1249MB/s bulk (8000 ints/s)
	 */
	/* what was last interrupt timeslice? */
	timepassed_us = 1000000/eitr;
	bytes_perint = bytes / timepassed_us; /* bytes/usec */

	switch (itr_setting) {
	case lowest_latency:
		if (bytes_perint > adapter->eitr_low)
			retval = low_latency;
		break;
	case low_latency:
		if (bytes_perint > adapter->eitr_high)
			retval = bulk_latency;
		else if (bytes_perint <= adapter->eitr_low)
			retval = lowest_latency;
		break;
	case bulk_latency:
		if (bytes_perint <= adapter->eitr_high)
			retval = low_latency;
		break;
	}

update_itr_done:
	return retval;
}

static void ixgbe_set_itr_msix(struct ixgbe_q_vector *q_vector)
{
	struct ixgbe_adapter *adapter = q_vector->adapter;
	struct ixgbe_hw *hw = &adapter->hw;
	u32 new_itr;
	u8 current_itr, ret_itr;
	int i, r_idx, v_idx = ((void *)q_vector - (void *)(adapter->q_vector)) /
			      sizeof(struct ixgbe_q_vector);
	struct ixgbe_ring *rx_ring, *tx_ring;

	r_idx = find_first_bit(q_vector->txr_idx, adapter->num_tx_queues);
	for (i = 0; i < q_vector->txr_count; i++) {
		tx_ring = &(adapter->tx_ring[r_idx]);
		ret_itr = ixgbe_update_itr(adapter, q_vector->eitr,
					   q_vector->tx_eitr,
					   tx_ring->total_packets,
					   tx_ring->total_bytes);
		/* if the result for this queue would decrease interrupt
		 * rate for this vector then use that result */
		q_vector->tx_eitr = ((q_vector->tx_eitr > ret_itr) ?
				    q_vector->tx_eitr - 1 : ret_itr);
		r_idx = find_next_bit(q_vector->txr_idx, adapter->num_tx_queues,
				      r_idx + 1);
	}

	r_idx = find_first_bit(q_vector->rxr_idx, adapter->num_rx_queues);
	for (i = 0; i < q_vector->rxr_count; i++) {
		rx_ring = &(adapter->rx_ring[r_idx]);
		ret_itr = ixgbe_update_itr(adapter, q_vector->eitr,
					   q_vector->rx_eitr,
					   rx_ring->total_packets,
					   rx_ring->total_bytes);
		/* if the result for this queue would decrease interrupt
		 * rate for this vector then use that result */
		q_vector->rx_eitr = ((q_vector->rx_eitr > ret_itr) ?
				    q_vector->rx_eitr - 1 : ret_itr);
		r_idx = find_next_bit(q_vector->rxr_idx, adapter->num_rx_queues,
				      r_idx + 1);
	}

	current_itr = max(q_vector->rx_eitr, q_vector->tx_eitr);

	switch (current_itr) {
	/* counts and packets in update_itr are dependent on these numbers */
	case lowest_latency:
		new_itr = 100000;
		break;
	case low_latency:
		new_itr = 20000; /* aka hwitr = ~200 */
		break;
	case bulk_latency:
	default:
		new_itr = 8000;
		break;
	}

	if (new_itr != q_vector->eitr) {
		u32 itr_reg;
		/* do an exponential smoothing */
		new_itr = ((q_vector->eitr * 90)/100) + ((new_itr * 10)/100);
		q_vector->eitr = new_itr;
		itr_reg = EITR_INTS_PER_SEC_TO_REG(new_itr);
		/* must write high and low 16 bits to reset counter */
		DPRINTK(TX_ERR, DEBUG, "writing eitr(%d): %08X\n", v_idx,
			itr_reg);
		IXGBE_WRITE_REG(hw, IXGBE_EITR(v_idx), itr_reg | (itr_reg)<<16);
	}

	return;
}

static irqreturn_t ixgbe_msix_lsc(int irq, void *data)
{
	struct net_device *netdev = data;
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	struct ixgbe_hw *hw = &adapter->hw;
	u32 eicr = IXGBE_READ_REG(hw, IXGBE_EICR);

	if (eicr & IXGBE_EICR_LSC) {
		adapter->lsc_int++;
		if (!test_bit(__IXGBE_DOWN, &adapter->state))
			mod_timer(&adapter->watchdog_timer, jiffies);
	}

	if (!test_bit(__IXGBE_DOWN, &adapter->state))
		IXGBE_WRITE_REG(hw, IXGBE_EIMS, IXGBE_EIMS_OTHER);

	return IRQ_HANDLED;
}

static irqreturn_t ixgbe_msix_clean_tx(int irq, void *data)
{
	struct ixgbe_q_vector *q_vector = data;
	struct ixgbe_adapter  *adapter = q_vector->adapter;
	struct ixgbe_ring     *txr;
	int i, r_idx;

	if (!q_vector->txr_count)
		return IRQ_HANDLED;

	r_idx = find_first_bit(q_vector->txr_idx, adapter->num_tx_queues);
	for (i = 0; i < q_vector->txr_count; i++) {
		txr = &(adapter->tx_ring[r_idx]);
#ifdef CONFIG_DCA
		if (adapter->flags & IXGBE_FLAG_DCA_ENABLED)
			ixgbe_update_tx_dca(adapter, txr);
#endif
		txr->total_bytes = 0;
		txr->total_packets = 0;
		ixgbe_clean_tx_irq(adapter, txr);
		r_idx = find_next_bit(q_vector->txr_idx, adapter->num_tx_queues,
				      r_idx + 1);
	}

	return IRQ_HANDLED;
}

/**
 * ixgbe_msix_clean_rx - single unshared vector rx clean (all queues)
 * @irq: unused
 * @data: pointer to our q_vector struct for this interrupt vector
 **/
static irqreturn_t ixgbe_msix_clean_rx(int irq, void *data)
{
	struct ixgbe_q_vector *q_vector = data;
	struct ixgbe_adapter  *adapter = q_vector->adapter;
	struct ixgbe_ring  *rxr;
	int r_idx;

	r_idx = find_first_bit(q_vector->rxr_idx, adapter->num_rx_queues);
	if (!q_vector->rxr_count)
		return IRQ_HANDLED;

	rxr = &(adapter->rx_ring[r_idx]);
	/* disable interrupts on this vector only */
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMC, rxr->v_idx);
	rxr->total_bytes = 0;
	rxr->total_packets = 0;
	netif_rx_schedule(adapter->netdev, &q_vector->napi);

	return IRQ_HANDLED;
}

static irqreturn_t ixgbe_msix_clean_many(int irq, void *data)
{
	ixgbe_msix_clean_rx(irq, data);
	ixgbe_msix_clean_tx(irq, data);

	return IRQ_HANDLED;
}

/**
 * ixgbe_clean_rxonly - msix (aka one shot) rx clean routine
 * @napi: napi struct with our devices info in it
 * @budget: amount of work driver is allowed to do this pass, in packets
 *
 **/
static int ixgbe_clean_rxonly(struct napi_struct *napi, int budget)
{
	struct ixgbe_q_vector *q_vector =
			       container_of(napi, struct ixgbe_q_vector, napi);
	struct ixgbe_adapter *adapter = q_vector->adapter;
	struct ixgbe_ring *rxr;
	int work_done = 0;
	long r_idx;

	r_idx = find_first_bit(q_vector->rxr_idx, adapter->num_rx_queues);
	rxr = &(adapter->rx_ring[r_idx]);
#ifdef CONFIG_DCA
	if (adapter->flags & IXGBE_FLAG_DCA_ENABLED)
		ixgbe_update_rx_dca(adapter, rxr);
#endif

	ixgbe_clean_rx_irq(adapter, rxr, &work_done, budget);

	/* If all Rx work done, exit the polling mode */
	if (work_done < budget) {
		netif_rx_complete(adapter->netdev, napi);
		if (adapter->rx_eitr < IXGBE_MIN_ITR_USECS)
			ixgbe_set_itr_msix(q_vector);
		if (!test_bit(__IXGBE_DOWN, &adapter->state))
			IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMS, rxr->v_idx);
	}

	return work_done;
}

static inline void map_vector_to_rxq(struct ixgbe_adapter *a, int v_idx,
				     int r_idx)
{
	a->q_vector[v_idx].adapter = a;
	set_bit(r_idx, a->q_vector[v_idx].rxr_idx);
	a->q_vector[v_idx].rxr_count++;
	a->rx_ring[r_idx].v_idx = 1 << v_idx;
}

static inline void map_vector_to_txq(struct ixgbe_adapter *a, int v_idx,
				     int r_idx)
{
	a->q_vector[v_idx].adapter = a;
	set_bit(r_idx, a->q_vector[v_idx].txr_idx);
	a->q_vector[v_idx].txr_count++;
	a->tx_ring[r_idx].v_idx = 1 << v_idx;
}

/**
 * ixgbe_map_rings_to_vectors - Maps descriptor rings to vectors
 * @adapter: board private structure to initialize
 * @vectors: allotted vector count for descriptor rings
 *
 * This function maps descriptor rings to the queue-specific vectors
 * we were allotted through the MSI-X enabling code.  Ideally, we'd have
 * one vector per ring/queue, but on a constrained vector budget, we
 * group the rings as "efficiently" as possible.  You would add new
 * mapping configurations in here.
 **/
static int ixgbe_map_rings_to_vectors(struct ixgbe_adapter *adapter,
				      int vectors)
{
	int v_start = 0;
	int rxr_idx = 0, txr_idx = 0;
	int rxr_remaining = adapter->num_rx_queues;
	int txr_remaining = adapter->num_tx_queues;
	int i, j;
	int rqpv, tqpv;
	int err = 0;

	/* No mapping required if MSI-X is disabled. */
	if (!(adapter->flags & IXGBE_FLAG_MSIX_ENABLED))
		goto out;

	/*
	 * The ideal configuration...
	 * We have enough vectors to map one per queue.
	 */
	if (vectors == adapter->num_rx_queues + adapter->num_tx_queues) {
		for (; rxr_idx < rxr_remaining; v_start++, rxr_idx++)
			map_vector_to_rxq(adapter, v_start, rxr_idx);

		for (; txr_idx < txr_remaining; v_start++, txr_idx++)
			map_vector_to_txq(adapter, v_start, txr_idx);

		goto out;
	}

	/*
	 * If we don't have enough vectors for a 1-to-1
	 * mapping, we'll have to group them so there are
	 * multiple queues per vector.
	 */
	/* Re-adjusting *qpv takes care of the remainder. */
	for (i = v_start; i < vectors; i++) {
		rqpv = DIV_ROUND_UP(rxr_remaining, vectors - i);
		for (j = 0; j < rqpv; j++) {
			map_vector_to_rxq(adapter, i, rxr_idx);
			rxr_idx++;
			rxr_remaining--;
		}
	}
	for (i = v_start; i < vectors; i++) {
		tqpv = DIV_ROUND_UP(txr_remaining, vectors - i);
		for (j = 0; j < tqpv; j++) {
			map_vector_to_txq(adapter, i, txr_idx);
			txr_idx++;
			txr_remaining--;
		}
	}

out:
	return err;
}

/**
 * ixgbe_request_msix_irqs - Initialize MSI-X interrupts
 * @adapter: board private structure
 *
 * ixgbe_request_msix_irqs allocates MSI-X vectors and requests
 * interrupts from the kernel.
 **/
static int ixgbe_request_msix_irqs(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	irqreturn_t (*handler)(int, void *);
	int i, vector, q_vectors, err;

	/* Decrement for Other and TCP Timer vectors */
	q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

	/* Map the Tx/Rx rings to the vectors we were allotted. */
	err = ixgbe_map_rings_to_vectors(adapter, q_vectors);
	if (err)
		goto out;

#define SET_HANDLER(_v) ((!(_v)->rxr_count) ? &ixgbe_msix_clean_tx : \
			 (!(_v)->txr_count) ? &ixgbe_msix_clean_rx : \
			 &ixgbe_msix_clean_many)
	for (vector = 0; vector < q_vectors; vector++) {
		handler = SET_HANDLER(&adapter->q_vector[vector]);
		sprintf(adapter->name[vector], "%s:v%d-%s",
			netdev->name, vector,
			(handler == &ixgbe_msix_clean_rx) ? "Rx" :
			 ((handler == &ixgbe_msix_clean_tx) ? "Tx" : "TxRx"));
		err = request_irq(adapter->msix_entries[vector].vector,
				  handler, 0, adapter->name[vector],
				  &(adapter->q_vector[vector]));
		if (err) {
			DPRINTK(PROBE, ERR,
				"request_irq failed for MSIX interrupt "
				"Error: %d\n", err);
			goto free_queue_irqs;
		}
	}

	sprintf(adapter->name[vector], "%s:lsc", netdev->name);
	err = request_irq(adapter->msix_entries[vector].vector,
			  &ixgbe_msix_lsc, 0, adapter->name[vector], netdev);
	if (err) {
		DPRINTK(PROBE, ERR,
			"request_irq for msix_lsc failed: %d\n", err);
		goto free_queue_irqs;
	}

	return 0;

free_queue_irqs:
	for (i = vector - 1; i >= 0; i--)
		free_irq(adapter->msix_entries[--vector].vector,
			 &(adapter->q_vector[i]));
	adapter->flags &= ~IXGBE_FLAG_MSIX_ENABLED;
	pci_disable_msix(adapter->pdev);
	kfree(adapter->msix_entries);
	adapter->msix_entries = NULL;
out:
	return err;
}

static void ixgbe_set_itr(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	struct ixgbe_q_vector *q_vector = adapter->q_vector;
	u8 current_itr;
	u32 new_itr = q_vector->eitr;
	struct ixgbe_ring *rx_ring = &adapter->rx_ring[0];
	struct ixgbe_ring *tx_ring = &adapter->tx_ring[0];

	q_vector->tx_eitr = ixgbe_update_itr(adapter, new_itr,
					     q_vector->tx_eitr,
					     tx_ring->total_packets,
					     tx_ring->total_bytes);
	q_vector->rx_eitr = ixgbe_update_itr(adapter, new_itr,
					     q_vector->rx_eitr,
					     rx_ring->total_packets,
					     rx_ring->total_bytes);

	current_itr = max(q_vector->rx_eitr, q_vector->tx_eitr);

	switch (current_itr) {
	/* counts and packets in update_itr are dependent on these numbers */
	case lowest_latency:
		new_itr = 100000;
		break;
	case low_latency:
		new_itr = 20000; /* aka hwitr = ~200 */
		break;
	case bulk_latency:
		new_itr = 8000;
		break;
	default:
		break;
	}

	if (new_itr != q_vector->eitr) {
		u32 itr_reg;
		/* do an exponential smoothing */
		new_itr = ((q_vector->eitr * 90)/100) + ((new_itr * 10)/100);
		q_vector->eitr = new_itr;
		itr_reg = EITR_INTS_PER_SEC_TO_REG(new_itr);
		/* must write high and low 16 bits to reset counter */
		IXGBE_WRITE_REG(hw, IXGBE_EITR(0), itr_reg | (itr_reg)<<16);
	}

	return;
}

static inline void ixgbe_irq_enable(struct ixgbe_adapter *adapter);

/**
 * ixgbe_intr - legacy mode Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 * @pt_regs: CPU registers structure
 **/
static irqreturn_t ixgbe_intr(int irq, void *data)
{
	struct net_device *netdev = data;
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	struct ixgbe_hw *hw = &adapter->hw;
	u32 eicr;


	/* for NAPI, using EIAM to auto-mask tx/rx interrupt bits on read
	 * therefore no explict interrupt disable is necessary */
	eicr = IXGBE_READ_REG(hw, IXGBE_EICR);
	if (!eicr)
		return IRQ_NONE;	/* Not our interrupt */

	if (eicr & IXGBE_EICR_LSC) {
		adapter->lsc_int++;
		if (!test_bit(__IXGBE_DOWN, &adapter->state))
			mod_timer(&adapter->watchdog_timer, jiffies);
	}


	if (netif_rx_schedule_prep(netdev, &adapter->q_vector[0].napi)) {
		adapter->tx_ring[0].total_packets = 0;
		adapter->tx_ring[0].total_bytes = 0;
		adapter->rx_ring[0].total_packets = 0;
		adapter->rx_ring[0].total_bytes = 0;
		/* would disable interrupts here but EIAM disabled it */
		__netif_rx_schedule(netdev, &adapter->q_vector[0].napi);
	}

	return IRQ_HANDLED;
}

static inline void ixgbe_reset_q_vectors(struct ixgbe_adapter *adapter)
{
	int i, q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

	for (i = 0; i < q_vectors; i++) {
		struct ixgbe_q_vector *q_vector = &adapter->q_vector[i];
		bitmap_zero(q_vector->rxr_idx, MAX_RX_QUEUES);
		bitmap_zero(q_vector->txr_idx, MAX_TX_QUEUES);
		q_vector->rxr_count = 0;
		q_vector->txr_count = 0;
	}
}

/**
 * ixgbe_request_irq - initialize interrupts
 * @adapter: board private structure
 *
 * Attempts to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 **/
static int ixgbe_request_irq(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	int err;

	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
		err = ixgbe_request_msix_irqs(adapter);
	} else if (adapter->flags & IXGBE_FLAG_MSI_ENABLED) {
		err = request_irq(adapter->pdev->irq, &ixgbe_intr, 0,
				  netdev->name, netdev);
	} else {
		err = request_irq(adapter->pdev->irq, &ixgbe_intr, IRQF_SHARED,
				  netdev->name, netdev);
	}

	if (err)
		DPRINTK(PROBE, ERR, "request_irq failed, Error %d\n", err);

	return err;
}

static void ixgbe_free_irq(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;

	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
		int i, q_vectors;

		q_vectors = adapter->num_msix_vectors;

		i = q_vectors - 1;
		free_irq(adapter->msix_entries[i].vector, netdev);

		i--;
		for (; i >= 0; i--) {
			free_irq(adapter->msix_entries[i].vector,
				 &(adapter->q_vector[i]));
		}

		ixgbe_reset_q_vectors(adapter);
	} else {
		free_irq(adapter->pdev->irq, netdev);
	}
}

/**
 * ixgbe_irq_disable - Mask off interrupt generation on the NIC
 * @adapter: board private structure
 **/
static inline void ixgbe_irq_disable(struct ixgbe_adapter *adapter)
{
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMC, ~0);
	IXGBE_WRITE_FLUSH(&adapter->hw);
	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
		int i;
		for (i = 0; i < adapter->num_msix_vectors; i++)
			synchronize_irq(adapter->msix_entries[i].vector);
	} else {
		synchronize_irq(adapter->pdev->irq);
	}
}

/**
 * ixgbe_irq_enable - Enable default interrupt generation settings
 * @adapter: board private structure
 **/
static inline void ixgbe_irq_enable(struct ixgbe_adapter *adapter)
{
	u32 mask;
	mask = IXGBE_EIMS_ENABLE_MASK;
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMS, mask);
	IXGBE_WRITE_FLUSH(&adapter->hw);
}

/**
 * ixgbe_configure_msi_and_legacy - Initialize PIN (INTA...) and MSI interrupts
 *
 **/
static void ixgbe_configure_msi_and_legacy(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;

	IXGBE_WRITE_REG(hw, IXGBE_EITR(0),
			EITR_INTS_PER_SEC_TO_REG(adapter->rx_eitr));

	ixgbe_set_ivar(adapter, IXGBE_IVAR_RX_QUEUE(0), 0);
	ixgbe_set_ivar(adapter, IXGBE_IVAR_TX_QUEUE(0), 0);

	map_vector_to_rxq(adapter, 0, 0);
	map_vector_to_txq(adapter, 0, 0);

	DPRINTK(HW, INFO, "Legacy interrupt IVAR setup done\n");
}

/**
 * ixgbe_configure_tx - Configure 8254x Transmit Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Tx unit of the MAC after a reset.
 **/
static void ixgbe_configure_tx(struct ixgbe_adapter *adapter)
{
	u64 tdba;
	struct ixgbe_hw *hw = &adapter->hw;
	u32 i, j, tdlen, txctrl;

	/* Setup the HW Tx Head and Tail descriptor pointers */
	for (i = 0; i < adapter->num_tx_queues; i++) {
		j = adapter->tx_ring[i].reg_idx;
		tdba = adapter->tx_ring[i].dma;
		tdlen = adapter->tx_ring[i].count *
			sizeof(union ixgbe_adv_tx_desc);
		IXGBE_WRITE_REG(hw, IXGBE_TDBAL(j),
				(tdba & DMA_32BIT_MASK));
		IXGBE_WRITE_REG(hw, IXGBE_TDBAH(j), (tdba >> 32));
		IXGBE_WRITE_REG(hw, IXGBE_TDLEN(j), tdlen);
		IXGBE_WRITE_REG(hw, IXGBE_TDH(j), 0);
		IXGBE_WRITE_REG(hw, IXGBE_TDT(j), 0);
		adapter->tx_ring[i].head = IXGBE_TDH(j);
		adapter->tx_ring[i].tail = IXGBE_TDT(j);
		/* Disable Tx Head Writeback RO bit, since this hoses
		 * bookkeeping if things aren't delivered in order.
		 */
		txctrl = IXGBE_READ_REG(hw, IXGBE_DCA_TXCTRL(i));
		txctrl &= ~IXGBE_DCA_TXCTRL_TX_WB_RO_EN;
		IXGBE_WRITE_REG(hw, IXGBE_DCA_TXCTRL(i), txctrl);
	}
}

#define PAGE_USE_COUNT(S) (((S) >> PAGE_SHIFT) + \
			(((S) & (PAGE_SIZE - 1)) ? 1 : 0))

#define IXGBE_SRRCTL_BSIZEHDRSIZE_SHIFT			2
/**
 * ixgbe_configure_rx - Configure 8254x Receive Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Rx unit of the MAC after a reset.
 **/
static void ixgbe_configure_rx(struct ixgbe_adapter *adapter)
{
	u64 rdba;
	struct ixgbe_hw *hw = &adapter->hw;
	struct net_device *netdev = adapter->netdev;
	int max_frame = netdev->mtu + ETH_HLEN + ETH_FCS_LEN;
	int i, j;
	u32 rdlen, rxctrl, rxcsum;
	u32 random[10];
	u32 fctrl, hlreg0;
	u32 pages;
	u32 reta = 0, mrqc, srrctl;

	/* Decide whether to use packet split mode or not */
	if (netdev->mtu > ETH_DATA_LEN)
		adapter->flags |= IXGBE_FLAG_RX_PS_ENABLED;
	else
		adapter->flags &= ~IXGBE_FLAG_RX_PS_ENABLED;

	/* Set the RX buffer length according to the mode */
	if (adapter->flags & IXGBE_FLAG_RX_PS_ENABLED) {
		adapter->rx_buf_len = IXGBE_RX_HDR_SIZE;
	} else {
		if (netdev->mtu <= ETH_DATA_LEN)
			adapter->rx_buf_len = MAXIMUM_ETHERNET_VLAN_SIZE;
		else
			adapter->rx_buf_len = ALIGN(max_frame, 1024);
	}

	fctrl = IXGBE_READ_REG(&adapter->hw, IXGBE_FCTRL);
	fctrl |= IXGBE_FCTRL_BAM;
	fctrl |= IXGBE_FCTRL_DPF; /* discard pause frames when FC enabled */
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_FCTRL, fctrl);

	hlreg0 = IXGBE_READ_REG(hw, IXGBE_HLREG0);
	if (adapter->netdev->mtu <= ETH_DATA_LEN)
		hlreg0 &= ~IXGBE_HLREG0_JUMBOEN;
	else
		hlreg0 |= IXGBE_HLREG0_JUMBOEN;
	IXGBE_WRITE_REG(hw, IXGBE_HLREG0, hlreg0);

	pages = PAGE_USE_COUNT(adapter->netdev->mtu);

	srrctl = IXGBE_READ_REG(&adapter->hw, IXGBE_SRRCTL(0));
	srrctl &= ~IXGBE_SRRCTL_BSIZEHDR_MASK;
	srrctl &= ~IXGBE_SRRCTL_BSIZEPKT_MASK;

	if (adapter->flags & IXGBE_FLAG_RX_PS_ENABLED) {
		srrctl |= PAGE_SIZE >> IXGBE_SRRCTL_BSIZEPKT_SHIFT;
		srrctl |= IXGBE_SRRCTL_DESCTYPE_HDR_SPLIT_ALWAYS;
		srrctl |= ((IXGBE_RX_HDR_SIZE <<
			    IXGBE_SRRCTL_BSIZEHDRSIZE_SHIFT) &
			   IXGBE_SRRCTL_BSIZEHDR_MASK);
	} else {
		srrctl |= IXGBE_SRRCTL_DESCTYPE_ADV_ONEBUF;

		if (adapter->rx_buf_len == MAXIMUM_ETHERNET_VLAN_SIZE)
			srrctl |=
			     IXGBE_RXBUFFER_2048 >> IXGBE_SRRCTL_BSIZEPKT_SHIFT;
		else
			srrctl |=
			     adapter->rx_buf_len >> IXGBE_SRRCTL_BSIZEPKT_SHIFT;
	}
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_SRRCTL(0), srrctl);

	rdlen = adapter->rx_ring[0].count * sizeof(union ixgbe_adv_rx_desc);
	/* disable receives while setting up the descriptors */
	rxctrl = IXGBE_READ_REG(hw, IXGBE_RXCTRL);
	IXGBE_WRITE_REG(hw, IXGBE_RXCTRL, rxctrl & ~IXGBE_RXCTRL_RXEN);

	/* 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++) {
		rdba = adapter->rx_ring[i].dma;
		IXGBE_WRITE_REG(hw, IXGBE_RDBAL(i), (rdba & DMA_32BIT_MASK));
		IXGBE_WRITE_REG(hw, IXGBE_RDBAH(i), (rdba >> 32));
		IXGBE_WRITE_REG(hw, IXGBE_RDLEN(i), rdlen);
		IXGBE_WRITE_REG(hw, IXGBE_RDH(i), 0);
		IXGBE_WRITE_REG(hw, IXGBE_RDT(i), 0);
		adapter->rx_ring[i].head = IXGBE_RDH(i);
		adapter->rx_ring[i].tail = IXGBE_RDT(i);
	}

	if (adapter->flags & IXGBE_FLAG_RSS_ENABLED) {
		/* Fill out redirection table */
		for (i = 0, j = 0; i < 128; i++, j++) {
			if (j == adapter->ring_feature[RING_F_RSS].indices)
				j = 0;
			/* reta = 4-byte sliding window of
			 * 0x00..(indices-1)(indices-1)00..etc. */
			reta = (reta << 8) | (j * 0x11);
			if ((i & 3) == 3)
				IXGBE_WRITE_REG(hw, IXGBE_RETA(i >> 2), reta);
		}

		/* Fill out hash function seeds */
		/* XXX use a random constant here to glue certain flows */
		get_random_bytes(&random[0], 40);
		for (i = 0; i < 10; i++)
			IXGBE_WRITE_REG(hw, IXGBE_RSSRK(i), random[i]);

		mrqc = IXGBE_MRQC_RSSEN
		    /* Perform hash on these packet types */
		    | IXGBE_MRQC_RSS_FIELD_IPV4
		    | IXGBE_MRQC_RSS_FIELD_IPV4_TCP
		    | IXGBE_MRQC_RSS_FIELD_IPV4_UDP
		    | IXGBE_MRQC_RSS_FIELD_IPV6_EX_TCP
		    | IXGBE_MRQC_RSS_FIELD_IPV6_EX
		    | IXGBE_MRQC_RSS_FIELD_IPV6
		    | IXGBE_MRQC_RSS_FIELD_IPV6_TCP
		    | IXGBE_MRQC_RSS_FIELD_IPV6_UDP
		    | IXGBE_MRQC_RSS_FIELD_IPV6_EX_UDP;
		IXGBE_WRITE_REG(hw, IXGBE_MRQC, mrqc);
	}

	rxcsum = IXGBE_READ_REG(hw, IXGBE_RXCSUM);

	if (adapter->flags & IXGBE_FLAG_RSS_ENABLED ||
	    adapter->flags & IXGBE_FLAG_RX_CSUM_ENABLED) {
		/* Disable indicating checksum in descriptor, enables
		 * RSS hash */
		rxcsum |= IXGBE_RXCSUM_PCSD;
	}
	if (!(rxcsum & IXGBE_RXCSUM_PCSD)) {
		/* Enable IPv4 payload checksum for UDP fragments
		 * if PCSD is not set */
		rxcsum |= IXGBE_RXCSUM_IPPCSE;
	}

	IXGBE_WRITE_REG(hw, IXGBE_RXCSUM, rxcsum);
}

static void ixgbe_vlan_rx_register(struct net_device *netdev,
				   struct vlan_group *grp)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	u32 ctrl;

	if (!test_bit(__IXGBE_DOWN, &adapter->state))
		ixgbe_irq_disable(adapter);
	adapter->vlgrp = grp;

	if (grp) {
		/* enable VLAN tag insert/strip */
		ctrl = IXGBE_READ_REG(&adapter->hw, IXGBE_VLNCTRL);
		ctrl |= IXGBE_VLNCTRL_VME | IXGBE_VLNCTRL_VFE;
		ctrl &= ~IXGBE_VLNCTRL_CFIEN;
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_VLNCTRL, ctrl);
	}

	if (!test_bit(__IXGBE_DOWN, &adapter->state))
		ixgbe_irq_enable(adapter);
}

static void ixgbe_vlan_rx_add_vid(struct net_device *netdev, u16 vid)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

	/* add VID to filter table */
	ixgbe_set_vfta(&adapter->hw, vid, 0, true);
}

static void ixgbe_vlan_rx_kill_vid(struct net_device *netdev, u16 vid)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

	if (!test_bit(__IXGBE_DOWN, &adapter->state))
		ixgbe_irq_disable(adapter);

	vlan_group_set_device(adapter->vlgrp, vid, NULL);

	if (!test_bit(__IXGBE_DOWN, &adapter->state))
		ixgbe_irq_enable(adapter);

	/* remove VID from filter table */
	ixgbe_set_vfta(&adapter->hw, vid, 0, false);
}

static void ixgbe_restore_vlan(struct ixgbe_adapter *adapter)
{
	ixgbe_vlan_rx_register(adapter->netdev, adapter->vlgrp);

	if (adapter->vlgrp) {
		u16 vid;
		for (vid = 0; vid < VLAN_GROUP_ARRAY_LEN; vid++) {
			if (!vlan_group_get_device(adapter->vlgrp, vid))
				continue;
			ixgbe_vlan_rx_add_vid(adapter->netdev, vid);
		}
	}
}

/**
 * ixgbe_set_multi - Multicast and Promiscuous mode set
 * @netdev: network interface device structure
 *
 * The set_multi entry point is called whenever the multicast address
 * list or the network interface flags are updated.  This routine is
 * responsible for configuring the hardware for proper multicast,
 * promiscuous mode, and all-multi behavior.
 **/
static void ixgbe_set_multi(struct net_device *netdev)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	struct ixgbe_hw *hw = &adapter->hw;
	struct dev_mc_list *mc_ptr;
	u8 *mta_list;
	u32 fctrl;
	int i;

	/* Check for Promiscuous and All Multicast modes */

	fctrl = IXGBE_READ_REG(hw, IXGBE_FCTRL);

	if (netdev->flags & IFF_PROMISC) {
		fctrl |= (IXGBE_FCTRL_UPE | IXGBE_FCTRL_MPE);
	} else if (netdev->flags & IFF_ALLMULTI) {
		fctrl |= IXGBE_FCTRL_MPE;
		fctrl &= ~IXGBE_FCTRL_UPE;
	} else {
		fctrl &= ~(IXGBE_FCTRL_UPE | IXGBE_FCTRL_MPE);
	}

	IXGBE_WRITE_REG(hw, IXGBE_FCTRL, fctrl);

	if (netdev->mc_count) {
		mta_list = kcalloc(netdev->mc_count, ETH_ALEN, GFP_ATOMIC);
		if (!mta_list)
			return;

		/* Shared function expects packed array of only addresses. */
		mc_ptr = netdev->mc_list;

		for (i = 0; i < netdev->mc_count; i++) {
			if (!mc_ptr)
				break;
			memcpy(mta_list + (i * ETH_ALEN), mc_ptr->dmi_addr,
			       ETH_ALEN);
			mc_ptr = mc_ptr->next;
		}

		ixgbe_update_mc_addr_list(hw, mta_list, i, 0);
		kfree(mta_list);
	} else {
		ixgbe_update_mc_addr_list(hw, NULL, 0, 0);
	}

}

static void ixgbe_napi_enable_all(struct ixgbe_adapter *adapter)
{
	int q_idx;
	struct ixgbe_q_vector *q_vector;
	int q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

	/* legacy and MSI only use one vector */
	if (!(adapter->flags & IXGBE_FLAG_MSIX_ENABLED))
		q_vectors = 1;

	for (q_idx = 0; q_idx < q_vectors; q_idx++) {
		q_vector = &adapter->q_vector[q_idx];
		if (!q_vector->rxr_count)
			continue;
		napi_enable(&q_vector->napi);
	}
}

static void ixgbe_napi_disable_all(struct ixgbe_adapter *adapter)
{
	int q_idx;
	struct ixgbe_q_vector *q_vector;
	int q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;

	/* legacy and MSI only use one vector */
	if (!(adapter->flags & IXGBE_FLAG_MSIX_ENABLED))
		q_vectors = 1;

	for (q_idx = 0; q_idx < q_vectors; q_idx++) {
		q_vector = &adapter->q_vector[q_idx];
		if (!q_vector->rxr_count)
			continue;
		napi_disable(&q_vector->napi);
	}
}

static void ixgbe_configure(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	int i;

	ixgbe_set_multi(netdev);

	ixgbe_restore_vlan(adapter);

	ixgbe_configure_tx(adapter);
	ixgbe_configure_rx(adapter);
	for (i = 0; i < adapter->num_rx_queues; i++)
		ixgbe_alloc_rx_buffers(adapter, &adapter->rx_ring[i],
					   (adapter->rx_ring[i].count - 1));
}

static int ixgbe_up_complete(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	struct ixgbe_hw *hw = &adapter->hw;
	int i, j = 0;
	int max_frame = netdev->mtu + ETH_HLEN + ETH_FCS_LEN;
	u32 txdctl, rxdctl, mhadd;
	u32 gpie;

	ixgbe_get_hw_control(adapter);

	if ((adapter->flags & IXGBE_FLAG_MSIX_ENABLED) ||
	    (adapter->flags & IXGBE_FLAG_MSI_ENABLED)) {
		if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
			gpie = (IXGBE_GPIE_MSIX_MODE | IXGBE_GPIE_EIAME |
				IXGBE_GPIE_PBA_SUPPORT | IXGBE_GPIE_OCD);
		} else {
			/* MSI only */
			gpie = 0;
		}
		/* XXX: to interrupt immediately for EICS writes, enable this */
		/* gpie |= IXGBE_GPIE_EIMEN; */
		IXGBE_WRITE_REG(hw, IXGBE_GPIE, gpie);
	}

	if (!(adapter->flags & IXGBE_FLAG_MSIX_ENABLED)) {
		/* legacy interrupts, use EIAM to auto-mask when reading EICR,
		 * specifically only auto mask tx and rx interrupts */
		IXGBE_WRITE_REG(hw, IXGBE_EIAM, IXGBE_EICS_RTX_QUEUE);
	}

	mhadd = IXGBE_READ_REG(hw, IXGBE_MHADD);
	if (max_frame != (mhadd >> IXGBE_MHADD_MFS_SHIFT)) {
		mhadd &= ~IXGBE_MHADD_MFS_MASK;
		mhadd |= max_frame << IXGBE_MHADD_MFS_SHIFT;

		IXGBE_WRITE_REG(hw, IXGBE_MHADD, mhadd);
	}

	for (i = 0; i < adapter->num_tx_queues; i++) {
		j = adapter->tx_ring[i].reg_idx;
		txdctl = IXGBE_READ_REG(hw, IXGBE_TXDCTL(j));
		txdctl |= IXGBE_TXDCTL_ENABLE;
		IXGBE_WRITE_REG(hw, IXGBE_TXDCTL(j), txdctl);
	}

	for (i = 0; i < adapter->num_rx_queues; i++) {
		j = adapter->rx_ring[i].reg_idx;
		rxdctl = IXGBE_READ_REG(hw, IXGBE_RXDCTL(j));
		/* enable PTHRESH=32 descriptors (half the internal cache)
		 * and HTHRESH=0 descriptors (to minimize latency on fetch),
		 * this also removes a pesky rx_no_buffer_count increment */
		rxdctl |= 0x0020;
		rxdctl |= IXGBE_RXDCTL_ENABLE;
		IXGBE_WRITE_REG(hw, IXGBE_RXDCTL(j), rxdctl);
	}
	/* enable all receives */
	rxdctl = IXGBE_READ_REG(hw, IXGBE_RXCTRL);
	rxdctl |= (IXGBE_RXCTRL_DMBYPS | IXGBE_RXCTRL_RXEN);
	IXGBE_WRITE_REG(hw, IXGBE_RXCTRL, rxdctl);

	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED)
		ixgbe_configure_msix(adapter);
	else
		ixgbe_configure_msi_and_legacy(adapter);

	clear_bit(__IXGBE_DOWN, &adapter->state);
	ixgbe_napi_enable_all(adapter);

	/* clear any pending interrupts, may auto mask */
	IXGBE_READ_REG(hw, IXGBE_EICR);

	ixgbe_irq_enable(adapter);

	/* bring the link up in the watchdog, this could race with our first
	 * link up interrupt but shouldn't be a problem */
	mod_timer(&adapter->watchdog_timer, jiffies);
	return 0;
}

void ixgbe_reinit_locked(struct ixgbe_adapter *adapter)
{
	WARN_ON(in_interrupt());
	while (test_and_set_bit(__IXGBE_RESETTING, &adapter->state))
		msleep(1);
	ixgbe_down(adapter);
	ixgbe_up(adapter);
	clear_bit(__IXGBE_RESETTING, &adapter->state);
}

int ixgbe_up(struct ixgbe_adapter *adapter)
{
	/* hardware has been reset, we need to reload some things */
	ixgbe_configure(adapter);

	return ixgbe_up_complete(adapter);
}

void ixgbe_reset(struct ixgbe_adapter *adapter)
{
	if (ixgbe_init_hw(&adapter->hw))
		DPRINTK(PROBE, ERR, "Hardware Error\n");

	/* reprogram the RAR[0] in case user changed it. */
	ixgbe_set_rar(&adapter->hw, 0, adapter->hw.mac.addr, 0, IXGBE_RAH_AV);

}

#ifdef CONFIG_PM
static int ixgbe_resume(struct pci_dev *pdev)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	u32 err;

	pci_set_power_state(pdev, PCI_D0);
	pci_restore_state(pdev);
	err = pci_enable_device(pdev);
	if (err) {
		printk(KERN_ERR "ixgbe: Cannot enable PCI device from " \
				"suspend\n");
		return err;
	}
	pci_set_master(pdev);

	pci_enable_wake(pdev, PCI_D3hot, 0);
	pci_enable_wake(pdev, PCI_D3cold, 0);

	if (netif_running(netdev)) {
		err = ixgbe_request_irq(adapter);
		if (err)
			return err;
	}

	ixgbe_reset(adapter);

	if (netif_running(netdev))
		ixgbe_up(adapter);

	netif_device_attach(netdev);

	return 0;
}
#endif

/**
 * ixgbe_clean_rx_ring - Free Rx Buffers per Queue
 * @adapter: board private structure
 * @rx_ring: ring to free buffers from
 **/
static void ixgbe_clean_rx_ring(struct ixgbe_adapter *adapter,
				struct ixgbe_ring *rx_ring)
{
	struct pci_dev *pdev = adapter->pdev;
	unsigned long size;
	unsigned int i;

	/* Free all the Rx ring sk_buffs */

	for (i = 0; i < rx_ring->count; i++) {
		struct ixgbe_rx_buffer *rx_buffer_info;

		rx_buffer_info = &rx_ring->rx_buffer_info[i];
		if (rx_buffer_info->dma) {
			pci_unmap_single(pdev, rx_buffer_info->dma,
					 adapter->rx_buf_len,
					 PCI_DMA_FROMDEVICE);
			rx_buffer_info->dma = 0;
		}
		if (rx_buffer_info->skb) {
			dev_kfree_skb(rx_buffer_info->skb);
			rx_buffer_info->skb = NULL;
		}
		if (!rx_buffer_info->page)
			continue;
		pci_unmap_page(pdev, rx_buffer_info->page_dma, PAGE_SIZE,
			       PCI_DMA_FROMDEVICE);
		rx_buffer_info->page_dma = 0;

		put_page(rx_buffer_info->page);
		rx_buffer_info->page = NULL;
	}

	size = sizeof(struct ixgbe_rx_buffer) * rx_ring->count;
	memset(rx_ring->rx_buffer_info, 0, size);

	/* Zero out the descriptor ring */
	memset(rx_ring->desc, 0, rx_ring->size);

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

	writel(0, adapter->hw.hw_addr + rx_ring->head);
	writel(0, adapter->hw.hw_addr + rx_ring->tail);
}

/**
 * ixgbe_clean_tx_ring - Free Tx Buffers
 * @adapter: board private structure
 * @tx_ring: ring to be cleaned
 **/
static void ixgbe_clean_tx_ring(struct ixgbe_adapter *adapter,
				struct ixgbe_ring *tx_ring)
{
	struct ixgbe_tx_buffer *tx_buffer_info;
	unsigned long size;
	unsigned int i;

	/* Free all the Tx ring sk_buffs */

	for (i = 0; i < tx_ring->count; i++) {
		tx_buffer_info = &tx_ring->tx_buffer_info[i];
		ixgbe_unmap_and_free_tx_resource(adapter, tx_buffer_info);
	}

	size = sizeof(struct ixgbe_tx_buffer) * tx_ring->count;
	memset(tx_ring->tx_buffer_info, 0, size);

	/* Zero out the descriptor ring */
	memset(tx_ring->desc, 0, tx_ring->size);

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

	writel(0, adapter->hw.hw_addr + tx_ring->head);
	writel(0, adapter->hw.hw_addr + tx_ring->tail);
}

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

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

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

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

void ixgbe_down(struct ixgbe_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	u32 rxctrl;

	/* signal that we are down to the interrupt handler */
	set_bit(__IXGBE_DOWN, &adapter->state);

	/* disable receives */
	rxctrl = IXGBE_READ_REG(&adapter->hw, IXGBE_RXCTRL);
	IXGBE_WRITE_REG(&adapter->hw, IXGBE_RXCTRL,
			rxctrl & ~IXGBE_RXCTRL_RXEN);

	netif_tx_disable(netdev);

	/* disable transmits in the hardware */

	/* flush both disables */
	IXGBE_WRITE_FLUSH(&adapter->hw);
	msleep(10);

	ixgbe_irq_disable(adapter);

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

	netif_carrier_off(netdev);
	netif_stop_queue(netdev);

	ixgbe_reset(adapter);
	ixgbe_clean_all_tx_rings(adapter);
	ixgbe_clean_all_rx_rings(adapter);

}

static int ixgbe_suspend(struct pci_dev *pdev, pm_message_t state)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
#ifdef CONFIG_PM
	int retval = 0;
#endif

	netif_device_detach(netdev);

	if (netif_running(netdev)) {
		ixgbe_down(adapter);
		ixgbe_free_irq(adapter);
	}

#ifdef CONFIG_PM
	retval = pci_save_state(pdev);
	if (retval)
		return retval;
#endif

	pci_enable_wake(pdev, PCI_D3hot, 0);
	pci_enable_wake(pdev, PCI_D3cold, 0);

	ixgbe_release_hw_control(adapter);

	pci_disable_device(pdev);

	pci_set_power_state(pdev, pci_choose_state(pdev, state));

	return 0;
}

static void ixgbe_shutdown(struct pci_dev *pdev)
{
	ixgbe_suspend(pdev, PMSG_SUSPEND);
}

/**
 * ixgbe_poll - NAPI Rx polling callback
 * @napi: structure for representing this polling device
 * @budget: how many packets driver is allowed to clean
 *
 * This function is used for legacy and MSI, NAPI mode
 **/
static int ixgbe_poll(struct napi_struct *napi, int budget)
{
	struct ixgbe_q_vector *q_vector = container_of(napi,
					  struct ixgbe_q_vector, napi);
	struct ixgbe_adapter *adapter = q_vector->adapter;
	int tx_cleaned = 0, work_done = 0;

#ifdef CONFIG_DCA
	if (adapter->flags & IXGBE_FLAG_DCA_ENABLED) {
		ixgbe_update_tx_dca(adapter, adapter->tx_ring);
		ixgbe_update_rx_dca(adapter, adapter->rx_ring);
	}
#endif

	tx_cleaned = ixgbe_clean_tx_irq(adapter, adapter->tx_ring);
	ixgbe_clean_rx_irq(adapter, adapter->rx_ring, &work_done, budget);

	if (tx_cleaned)
		work_done = budget;

	/* If budget not fully consumed, exit the polling mode */
	if (work_done < budget) {
		netif_rx_complete(adapter->netdev, napi);
		if (adapter->rx_eitr < IXGBE_MIN_ITR_USECS)
			ixgbe_set_itr(adapter);
		if (!test_bit(__IXGBE_DOWN, &adapter->state))
			ixgbe_irq_enable(adapter);
	}

	return work_done;
}

/**
 * ixgbe_tx_timeout - Respond to a Tx Hang
 * @netdev: network interface device structure
 **/
static void ixgbe_tx_timeout(struct net_device *netdev)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

	/* Do the reset outside of interrupt context */
	schedule_work(&adapter->reset_task);
}

static void ixgbe_reset_task(struct work_struct *work)
{
	struct ixgbe_adapter *adapter;
	adapter = container_of(work, struct ixgbe_adapter, reset_task);

	adapter->tx_timeout_count++;

	ixgbe_reinit_locked(adapter);
}

static void ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter,
				       int vectors)
{
	int err, vector_threshold;

	/* We'll want at least 3 (vector_threshold):
	 * 1) TxQ[0] Cleanup
	 * 2) RxQ[0] Cleanup
	 * 3) Other (Link Status Change, etc.)
	 * 4) TCP Timer (optional)
	 */
	vector_threshold = MIN_MSIX_COUNT;

	/* The more we get, the more we will assign to Tx/Rx Cleanup
	 * for the separate queues...where Rx Cleanup >= Tx Cleanup.
	 * Right now, we simply care about how many we'll get; we'll
	 * set them up later while requesting irq's.
	 */
	while (vectors >= vector_threshold) {
		err = pci_enable_msix(adapter->pdev, adapter->msix_entries,
				      vectors);
		if (!err) /* Success in acquiring all requested vectors. */
			break;
		else if (err < 0)
			vectors = 0; /* Nasty failure, quit now */
		else /* err == number of vectors we should try again with */
			vectors = err;
	}

	if (vectors < vector_threshold) {
		/* Can't allocate enough MSI-X interrupts?  Oh well.
		 * This just means we'll go with either a single MSI
		 * vector or fall back to legacy interrupts.
		 */
		DPRINTK(HW, DEBUG, "Unable to allocate MSI-X interrupts\n");
		adapter->flags &= ~IXGBE_FLAG_MSIX_ENABLED;
		kfree(adapter->msix_entries);
		adapter->msix_entries = NULL;
		adapter->flags &= ~IXGBE_FLAG_RSS_ENABLED;
		adapter->num_tx_queues = 1;
		adapter->num_rx_queues = 1;
	} else {
		adapter->flags |= IXGBE_FLAG_MSIX_ENABLED; /* Woot! */
		adapter->num_msix_vectors = vectors;
	}
}

static void __devinit ixgbe_set_num_queues(struct ixgbe_adapter *adapter)
{
	int nrq, ntq;
	int feature_mask = 0, rss_i, rss_m;

	/* Number of supported queues */
	switch (adapter->hw.mac.type) {
	case ixgbe_mac_82598EB:
		rss_i = adapter->ring_feature[RING_F_RSS].indices;
		rss_m = 0;
		feature_mask |= IXGBE_FLAG_RSS_ENABLED;

		switch (adapter->flags & feature_mask) {
		case (IXGBE_FLAG_RSS_ENABLED):
			rss_m = 0xF;
			nrq = rss_i;
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
			ntq = rss_i;
#else
			ntq = 1;
#endif
			break;
		case 0:
		default:
			rss_i = 0;
			rss_m = 0;
			nrq = 1;
			ntq = 1;
			break;
		}

		adapter->ring_feature[RING_F_RSS].indices = rss_i;
		adapter->ring_feature[RING_F_RSS].mask = rss_m;
		break;
	default:
		nrq = 1;
		ntq = 1;
		break;
	}

	adapter->num_rx_queues = nrq;
	adapter->num_tx_queues = ntq;
}

/**
 * ixgbe_cache_ring_register - Descriptor ring to register mapping
 * @adapter: board private structure to initialize
 *
 * Once we know the feature-set enabled for the device, we'll cache
 * the register offset the descriptor ring is assigned to.
 **/
static void __devinit ixgbe_cache_ring_register(struct ixgbe_adapter *adapter)
{
	/* TODO: Remove all uses of the indices in the cases where multiple
	 *       features are OR'd together, if the feature set makes sense.
	 */
	int feature_mask = 0, rss_i;
	int i, txr_idx, rxr_idx;

	/* Number of supported queues */
	switch (adapter->hw.mac.type) {
	case ixgbe_mac_82598EB:
		rss_i = adapter->ring_feature[RING_F_RSS].indices;
		txr_idx = 0;
		rxr_idx = 0;
		feature_mask |= IXGBE_FLAG_RSS_ENABLED;
		switch (adapter->flags & feature_mask) {
		case (IXGBE_FLAG_RSS_ENABLED):
			for (i = 0; i < adapter->num_rx_queues; i++)
				adapter->rx_ring[i].reg_idx = i;
			for (i = 0; i < adapter->num_tx_queues; i++)
				adapter->tx_ring[i].reg_idx = i;
			break;
		case 0:
		default:
			break;
		}
		break;
	default:
		break;
	}
}

/**
 * ixgbe_alloc_queues - Allocate memory for all rings
 * @adapter: board private structure to initialize
 *
 * We allocate one ring per queue at run-time since we don't know the
 * number of queues at compile-time.  The polling_netdev array is
 * intended for Multiqueue, but should work fine with a single queue.
 **/
static int __devinit ixgbe_alloc_queues(struct ixgbe_adapter *adapter)
{
	int i;

	adapter->tx_ring = kcalloc(adapter->num_tx_queues,
				   sizeof(struct ixgbe_ring), GFP_KERNEL);
	if (!adapter->tx_ring)
		goto err_tx_ring_allocation;

	adapter->rx_ring = kcalloc(adapter->num_rx_queues,
				   sizeof(struct ixgbe_ring), GFP_KERNEL);
	if (!adapter->rx_ring)
		goto err_rx_ring_allocation;

	for (i = 0; i < adapter->num_tx_queues; i++) {
		adapter->tx_ring[i].count = IXGBE_DEFAULT_TXD;
		adapter->tx_ring[i].queue_index = i;
	}
	for (i = 0; i < adapter->num_rx_queues; i++) {
		adapter->rx_ring[i].count = IXGBE_DEFAULT_RXD;
		adapter->rx_ring[i].queue_index = i;
	}

	ixgbe_cache_ring_register(adapter);

	return 0;

err_rx_ring_allocation:
	kfree(adapter->tx_ring);
err_tx_ring_allocation:
	return -ENOMEM;
}

/**
 * ixgbe_set_interrupt_capability - set MSI-X or MSI if supported
 * @adapter: board private structure to initialize
 *
 * Attempt to configure the interrupts using the best available
 * capabilities of the hardware and the kernel.
 **/
static int __devinit ixgbe_set_interrupt_capability(struct ixgbe_adapter
						    *adapter)
{
	int err = 0;
	int vector, v_budget;

	/*
	 * It's easy to be greedy for MSI-X vectors, but it really
	 * doesn't do us much good if we have a lot more vectors
	 * than CPU's.  So let's be conservative and only ask for
	 * (roughly) twice the number of vectors as there are CPU's.
	 */
	v_budget = min(adapter->num_rx_queues + adapter->num_tx_queues,
		       (int)(num_online_cpus() * 2)) + NON_Q_VECTORS;

	/*
	 * At the same time, hardware can only support a maximum of
	 * MAX_MSIX_COUNT vectors.  With features such as RSS and VMDq,
	 * we can easily reach upwards of 64 Rx descriptor queues and
	 * 32 Tx queues.  Thus, we cap it off in those rare cases where
	 * the cpu count also exceeds our vector limit.
	 */
	v_budget = min(v_budget, MAX_MSIX_COUNT);

	/* A failure in MSI-X entry allocation isn't fatal, but it does
	 * mean we disable MSI-X capabilities of the adapter. */
	adapter->msix_entries = kcalloc(v_budget,
					sizeof(struct msix_entry), GFP_KERNEL);
	if (!adapter->msix_entries) {
		adapter->flags &= ~IXGBE_FLAG_RSS_ENABLED;
		ixgbe_set_num_queues(adapter);
		kfree(adapter->tx_ring);
		kfree(adapter->rx_ring);
		err = ixgbe_alloc_queues(adapter);
		if (err) {
			DPRINTK(PROBE, ERR, "Unable to allocate memory "
					    "for queues\n");
			goto out;
		}

		goto try_msi;
	}

	for (vector = 0; vector < v_budget; vector++)
		adapter->msix_entries[vector].entry = vector;

	ixgbe_acquire_msix_vectors(adapter, v_budget);

	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED)
		goto out;

try_msi:
	err = pci_enable_msi(adapter->pdev);
	if (!err) {
		adapter->flags |= IXGBE_FLAG_MSI_ENABLED;
	} else {
		DPRINTK(HW, DEBUG, "Unable to allocate MSI interrupt, "
				   "falling back to legacy.  Error: %d\n", err);
		/* reset err */
		err = 0;
	}

out:
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	/* Notify the stack of the (possibly) reduced Tx Queue count. */
	adapter->netdev->egress_subqueue_count = adapter->num_tx_queues;
#endif

	return err;
}

static void ixgbe_reset_interrupt_capability(struct ixgbe_adapter *adapter)
{
	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
		adapter->flags &= ~IXGBE_FLAG_MSIX_ENABLED;
		pci_disable_msix(adapter->pdev);
		kfree(adapter->msix_entries);
		adapter->msix_entries = NULL;
	} else if (adapter->flags & IXGBE_FLAG_MSI_ENABLED) {
		adapter->flags &= ~IXGBE_FLAG_MSI_ENABLED;
		pci_disable_msi(adapter->pdev);
	}
	return;
}

/**
 * ixgbe_init_interrupt_scheme - Determine proper interrupt scheme
 * @adapter: board private structure to initialize
 *
 * We determine which interrupt scheme to use based on...
 * - Kernel support (MSI, MSI-X)
 *   - which can be user-defined (via MODULE_PARAM)
 * - Hardware queue count (num_*_queues)
 *   - defined by miscellaneous hardware support/features (RSS, etc.)
 **/
static int __devinit ixgbe_init_interrupt_scheme(struct ixgbe_adapter *adapter)
{
	int err;

	/* Number of supported queues */
	ixgbe_set_num_queues(adapter);

	err = ixgbe_alloc_queues(adapter);
	if (err) {
		DPRINTK(PROBE, ERR, "Unable to allocate memory for queues\n");
		goto err_alloc_queues;
	}

	err = ixgbe_set_interrupt_capability(adapter);
	if (err) {
		DPRINTK(PROBE, ERR, "Unable to setup interrupt capabilities\n");
		goto err_set_interrupt;
	}

	DPRINTK(DRV, INFO, "Multiqueue %s: Rx Queue count = %u, "
			   "Tx Queue count = %u\n",
		(adapter->num_rx_queues > 1) ? "Enabled" :
		"Disabled", adapter->num_rx_queues, adapter->num_tx_queues);

	set_bit(__IXGBE_DOWN, &adapter->state);

	return 0;

err_set_interrupt:
	kfree(adapter->tx_ring);
	kfree(adapter->rx_ring);
err_alloc_queues:
	return err;
}

/**
 * ixgbe_sw_init - Initialize general software structures (struct ixgbe_adapter)
 * @adapter: board private structure to initialize
 *
 * ixgbe_sw_init initializes the Adapter private data structure.
 * Fields are initialized based on PCI device information and
 * OS network device settings (MTU size).
 **/
static int __devinit ixgbe_sw_init(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	struct pci_dev *pdev = adapter->pdev;
	unsigned int rss;

	/* Set capability flags */
	rss = min(IXGBE_MAX_RSS_INDICES, (int)num_online_cpus());
	adapter->ring_feature[RING_F_RSS].indices = rss;
	adapter->flags |= IXGBE_FLAG_RSS_ENABLED;

	/* Enable Dynamic interrupt throttling by default */
	adapter->rx_eitr = 1;
	adapter->tx_eitr = 1;

	/* default flow control settings */
	hw->fc.original_type = ixgbe_fc_full;
	hw->fc.type = ixgbe_fc_full;

	/* select 10G link by default */
	hw->mac.link_mode_select = IXGBE_AUTOC_LMS_10G_LINK_NO_AN;
	if (hw->mac.ops.reset(hw)) {
		dev_err(&pdev->dev, "HW Init failed\n");
		return -EIO;
	}
	if (hw->mac.ops.setup_link_speed(hw, IXGBE_LINK_SPEED_10GB_FULL, true,
					 false)) {
		dev_err(&pdev->dev, "Link Speed setup failed\n");
		return -EIO;
	}

	/* initialize eeprom parameters */
	if (ixgbe_init_eeprom(hw)) {
		dev_err(&pdev->dev, "EEPROM initialization failed\n");
		return -EIO;
	}

	/* enable rx csum by default */
	adapter->flags |= IXGBE_FLAG_RX_CSUM_ENABLED;

	set_bit(__IXGBE_DOWN, &adapter->state);

	return 0;
}

/**
 * ixgbe_setup_tx_resources - allocate Tx resources (Descriptors)
 * @adapter: board private structure
 * @txdr:    tx descriptor ring (for a specific queue) to setup
 *
 * Return 0 on success, negative on failure
 **/
int ixgbe_setup_tx_resources(struct ixgbe_adapter *adapter,
			     struct ixgbe_ring *txdr)
{
	struct pci_dev *pdev = adapter->pdev;
	int size;

	size = sizeof(struct ixgbe_tx_buffer) * txdr->count;
	txdr->tx_buffer_info = vmalloc(size);
	if (!txdr->tx_buffer_info) {
		DPRINTK(PROBE, ERR,
		"Unable to allocate memory for the transmit descriptor ring\n");
		return -ENOMEM;
	}
	memset(txdr->tx_buffer_info, 0, size);

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

	txdr->desc = pci_alloc_consistent(pdev, txdr->size, &txdr->dma);
	if (!txdr->desc) {
		vfree(txdr->tx_buffer_info);
		DPRINTK(PROBE, ERR,
			"Memory allocation failed for the tx desc ring\n");
		return -ENOMEM;
	}

	txdr->next_to_use = 0;
	txdr->next_to_clean = 0;
	txdr->work_limit = txdr->count;

	return 0;
}

/**
 * ixgbe_setup_rx_resources - allocate Rx resources (Descriptors)
 * @adapter: board private structure
 * @rxdr:    rx descriptor ring (for a specific queue) to setup
 *
 * Returns 0 on success, negative on failure
 **/
int ixgbe_setup_rx_resources(struct ixgbe_adapter *adapter,
			     struct ixgbe_ring *rxdr)
{
	struct pci_dev *pdev = adapter->pdev;
	int size;

	size = sizeof(struct ixgbe_rx_buffer) * rxdr->count;
	rxdr->rx_buffer_info = vmalloc(size);
	if (!rxdr->rx_buffer_info) {
		DPRINTK(PROBE, ERR,
			"vmalloc allocation failed for the rx desc ring\n");
		return -ENOMEM;
	}
	memset(rxdr->rx_buffer_info, 0, size);

	/* Round up to nearest 4K */
	rxdr->size = rxdr->count * sizeof(union ixgbe_adv_rx_desc);
	rxdr->size = ALIGN(rxdr->size, 4096);

	rxdr->desc = pci_alloc_consistent(pdev, rxdr->size, &rxdr->dma);

	if (!rxdr->desc) {
		DPRINTK(PROBE, ERR,
			"Memory allocation failed for the rx desc ring\n");
		vfree(rxdr->rx_buffer_info);
		return -ENOMEM;
	}

	rxdr->next_to_clean = 0;
	rxdr->next_to_use = 0;

	return 0;
}

/**
 * ixgbe_free_tx_resources - Free Tx Resources per Queue
 * @adapter: board private structure
 * @tx_ring: Tx descriptor ring for a specific queue
 *
 * Free all transmit software resources
 **/
static void ixgbe_free_tx_resources(struct ixgbe_adapter *adapter,
				    struct ixgbe_ring *tx_ring)
{
	struct pci_dev *pdev = adapter->pdev;

	ixgbe_clean_tx_ring(adapter, tx_ring);

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

	pci_free_consistent(pdev, tx_ring->size, tx_ring->desc, tx_ring->dma);

	tx_ring->desc = NULL;
}

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

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

/**
 * ixgbe_free_rx_resources - Free Rx Resources
 * @adapter: board private structure
 * @rx_ring: ring to clean the resources from
 *
 * Free all receive software resources
 **/
static void ixgbe_free_rx_resources(struct ixgbe_adapter *adapter,
				    struct ixgbe_ring *rx_ring)
{
	struct pci_dev *pdev = adapter->pdev;

	ixgbe_clean_rx_ring(adapter, rx_ring);

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

	pci_free_consistent(pdev, rx_ring->size, rx_ring->desc, rx_ring->dma);

	rx_ring->desc = NULL;
}

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

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

/**
 * ixgbe_setup_all_tx_resources - allocate all queues Tx resources
 * @adapter: board private structure
 *
 * If this function returns with an error, then it's possible one or
 * more of the rings is populated (while the rest are not).  It is the
 * callers duty to clean those orphaned rings.
 *
 * Return 0 on success, negative on failure
 **/
static int ixgbe_setup_all_tx_resources(struct ixgbe_adapter *adapter)
{
	int i, err = 0;

	for (i = 0; i < adapter->num_tx_queues; i++) {
		err = ixgbe_setup_tx_resources(adapter, &adapter->tx_ring[i]);
		if (err) {
			DPRINTK(PROBE, ERR,
				"Allocation for Tx Queue %u failed\n", i);
			break;
		}
	}

	return err;
}

/**
 * ixgbe_setup_all_rx_resources - allocate all queues Rx resources
 * @adapter: board private structure
 *
 * If this function returns with an error, then it's possible one or
 * more of the rings is populated (while the rest are not).  It is the
 * callers duty to clean those orphaned rings.
 *
 * Return 0 on success, negative on failure
 **/

static int ixgbe_setup_all_rx_resources(struct ixgbe_adapter *adapter)
{
	int i, err = 0;

	for (i = 0; i < adapter->num_rx_queues; i++) {
		err = ixgbe_setup_rx_resources(adapter, &adapter->rx_ring[i]);
		if (err) {
			DPRINTK(PROBE, ERR,
				"Allocation for Rx Queue %u failed\n", i);
			break;
		}
	}

	return err;
}

/**
 * ixgbe_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 ixgbe_change_mtu(struct net_device *netdev, int new_mtu)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN;

	if ((max_frame < (ETH_ZLEN + ETH_FCS_LEN)) ||
	    (max_frame > IXGBE_MAX_JUMBO_FRAME_SIZE))
		return -EINVAL;

	DPRINTK(PROBE, INFO, "changing MTU from %d to %d\n",
		netdev->mtu, new_mtu);
	/* must set new MTU before calling down or up */
	netdev->mtu = new_mtu;

	if (netif_running(netdev))
		ixgbe_reinit_locked(adapter);

	return 0;
}

/**
 * ixgbe_open - Called when a network interface is made active
 * @netdev: network interface device structure
 *
 * Returns 0 on success, negative value on failure
 *
 * The open entry point is called when a network interface is made
 * active by the system (IFF_UP).  At this point all resources needed
 * for transmit and receive operations are allocated, the interrupt
 * handler is registered with the OS, the watchdog timer is started,
 * and the stack is notified that the interface is ready.
 **/
static int ixgbe_open(struct net_device *netdev)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	int err;

	/* disallow open during test */
	if (test_bit(__IXGBE_TESTING, &adapter->state))
		return -EBUSY;

	/* allocate transmit descriptors */
	err = ixgbe_setup_all_tx_resources(adapter);
	if (err)
		goto err_setup_tx;

	/* allocate receive descriptors */
	err = ixgbe_setup_all_rx_resources(adapter);
	if (err)
		goto err_setup_rx;

	ixgbe_configure(adapter);

	err = ixgbe_request_irq(adapter);
	if (err)
		goto err_req_irq;

	err = ixgbe_up_complete(adapter);
	if (err)
		goto err_up;

	return 0;

err_up:
	ixgbe_release_hw_control(adapter);
	ixgbe_free_irq(adapter);
err_req_irq:
	ixgbe_free_all_rx_resources(adapter);
err_setup_rx:
	ixgbe_free_all_tx_resources(adapter);
err_setup_tx:
	ixgbe_reset(adapter);

	return err;
}

/**
 * ixgbe_close - Disables a network interface
 * @netdev: network interface device structure
 *
 * Returns 0, this is not allowed to fail
 *
 * The close entry point is called when an interface is de-activated
 * by the OS.  The hardware is still under the drivers control, but
 * needs to be disabled.  A global MAC reset is issued to stop the
 * hardware, and all transmit and receive resources are freed.
 **/
static int ixgbe_close(struct net_device *netdev)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

	ixgbe_down(adapter);
	ixgbe_free_irq(adapter);

	ixgbe_free_all_tx_resources(adapter);
	ixgbe_free_all_rx_resources(adapter);

	ixgbe_release_hw_control(adapter);

	return 0;
}

/**
 * ixgbe_update_stats - Update the board statistics counters.
 * @adapter: board private structure
 **/
void ixgbe_update_stats(struct ixgbe_adapter *adapter)
{
	struct ixgbe_hw *hw = &adapter->hw;
	u64 total_mpc = 0;
	u32 i, missed_rx = 0, mpc, bprc, lxon, lxoff, xon_off_tot;

	adapter->stats.crcerrs += IXGBE_READ_REG(hw, IXGBE_CRCERRS);
	for (i = 0; i < 8; i++) {
		/* for packet buffers not used, the register should read 0 */
		mpc = IXGBE_READ_REG(hw, IXGBE_MPC(i));
		missed_rx += mpc;
		adapter->stats.mpc[i] += mpc;
		total_mpc += adapter->stats.mpc[i];
		adapter->stats.rnbc[i] += IXGBE_READ_REG(hw, IXGBE_RNBC(i));
	}
	adapter->stats.gprc += IXGBE_READ_REG(hw, IXGBE_GPRC);
	/* work around hardware counting issue */
	adapter->stats.gprc -= missed_rx;

	/* 82598 hardware only has a 32 bit counter in the high register */
	adapter->stats.gorc += IXGBE_READ_REG(hw, IXGBE_GORCH);
	adapter->stats.gotc += IXGBE_READ_REG(hw, IXGBE_GOTCH);
	adapter->stats.tor += IXGBE_READ_REG(hw, IXGBE_TORH);
	bprc = IXGBE_READ_REG(hw, IXGBE_BPRC);
	adapter->stats.bprc += bprc;
	adapter->stats.mprc += IXGBE_READ_REG(hw, IXGBE_MPRC);
	adapter->stats.mprc -= bprc;
	adapter->stats.roc += IXGBE_READ_REG(hw, IXGBE_ROC);
	adapter->stats.prc64 += IXGBE_READ_REG(hw, IXGBE_PRC64);
	adapter->stats.prc127 += IXGBE_READ_REG(hw, IXGBE_PRC127);
	adapter->stats.prc255 += IXGBE_READ_REG(hw, IXGBE_PRC255);
	adapter->stats.prc511 += IXGBE_READ_REG(hw, IXGBE_PRC511);
	adapter->stats.prc1023 += IXGBE_READ_REG(hw, IXGBE_PRC1023);
	adapter->stats.prc1522 += IXGBE_READ_REG(hw, IXGBE_PRC1522);
	adapter->stats.rlec += IXGBE_READ_REG(hw, IXGBE_RLEC);
	adapter->stats.lxonrxc += IXGBE_READ_REG(hw, IXGBE_LXONRXC);
	adapter->stats.lxoffrxc += IXGBE_READ_REG(hw, IXGBE_LXOFFRXC);
	lxon = IXGBE_READ_REG(hw, IXGBE_LXONTXC);
	adapter->stats.lxontxc += lxon;
	lxoff = IXGBE_READ_REG(hw, IXGBE_LXOFFTXC);
	adapter->stats.lxofftxc += lxoff;
	adapter->stats.ruc += IXGBE_READ_REG(hw, IXGBE_RUC);
	adapter->stats.gptc += IXGBE_READ_REG(hw, IXGBE_GPTC);
	adapter->stats.mptc += IXGBE_READ_REG(hw, IXGBE_MPTC);
	/*
	 * 82598 errata - tx of flow control packets is included in tx counters
	 */
	xon_off_tot = lxon + lxoff;
	adapter->stats.gptc -= xon_off_tot;
	adapter->stats.mptc -= xon_off_tot;
	adapter->stats.gotc -= (xon_off_tot * (ETH_ZLEN + ETH_FCS_LEN));
	adapter->stats.ruc += IXGBE_READ_REG(hw, IXGBE_RUC);
	adapter->stats.rfc += IXGBE_READ_REG(hw, IXGBE_RFC);
	adapter->stats.rjc += IXGBE_READ_REG(hw, IXGBE_RJC);
	adapter->stats.tpr += IXGBE_READ_REG(hw, IXGBE_TPR);
	adapter->stats.ptc64 += IXGBE_READ_REG(hw, IXGBE_PTC64);
	adapter->stats.ptc64 -= xon_off_tot;
	adapter->stats.ptc127 += IXGBE_READ_REG(hw, IXGBE_PTC127);
	adapter->stats.ptc255 += IXGBE_READ_REG(hw, IXGBE_PTC255);
	adapter->stats.ptc511 += IXGBE_READ_REG(hw, IXGBE_PTC511);
	adapter->stats.ptc1023 += IXGBE_READ_REG(hw, IXGBE_PTC1023);
	adapter->stats.ptc1522 += IXGBE_READ_REG(hw, IXGBE_PTC1522);
	adapter->stats.bptc += IXGBE_READ_REG(hw, IXGBE_BPTC);

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

	/* Rx Errors */
	adapter->net_stats.rx_errors = adapter->stats.crcerrs +
						adapter->stats.rlec;
	adapter->net_stats.rx_dropped = 0;
	adapter->net_stats.rx_length_errors = adapter->stats.rlec;
	adapter->net_stats.rx_crc_errors = adapter->stats.crcerrs;
	adapter->net_stats.rx_missed_errors = total_mpc;
}

/**
 * ixgbe_watchdog - Timer Call-back
 * @data: pointer to adapter cast into an unsigned long
 **/
static void ixgbe_watchdog(unsigned long data)
{
	struct ixgbe_adapter *adapter = (struct ixgbe_adapter *)data;
	struct net_device *netdev = adapter->netdev;
	bool link_up;
	u32 link_speed = 0;
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	int i;
#endif

	adapter->hw.mac.ops.check_link(&adapter->hw, &(link_speed), &link_up);

	if (link_up) {
		if (!netif_carrier_ok(netdev)) {
			u32 frctl = IXGBE_READ_REG(&adapter->hw, IXGBE_FCTRL);
			u32 rmcs = IXGBE_READ_REG(&adapter->hw, IXGBE_RMCS);
#define FLOW_RX (frctl & IXGBE_FCTRL_RFCE)
#define FLOW_TX (rmcs & IXGBE_RMCS_TFCE_802_3X)
			DPRINTK(LINK, INFO, "NIC Link is Up %s, "
				"Flow Control: %s\n",
				(link_speed == IXGBE_LINK_SPEED_10GB_FULL ?
				 "10 Gbps" :
				 (link_speed == IXGBE_LINK_SPEED_1GB_FULL ?
				  "1 Gbps" : "unknown speed")),
				((FLOW_RX && FLOW_TX) ? "RX/TX" :
				 (FLOW_RX ? "RX" :
				 (FLOW_TX ? "TX" : "None"))));

			netif_carrier_on(netdev);
			netif_wake_queue(netdev);
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
			for (i = 0; i < adapter->num_tx_queues; i++)
				netif_wake_subqueue(netdev, i);
#endif
		} else {
			/* Force detection of hung controller */
			adapter->detect_tx_hung = true;
		}
	} else {
		if (netif_carrier_ok(netdev)) {
			DPRINTK(LINK, INFO, "NIC Link is Down\n");
			netif_carrier_off(netdev);
			netif_stop_queue(netdev);
		}
	}

	ixgbe_update_stats(adapter);

	if (!test_bit(__IXGBE_DOWN, &adapter->state)) {
		/* Cause software interrupt to ensure rx rings are cleaned */
		if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
			u32 eics =
			 (1 << (adapter->num_msix_vectors - NON_Q_VECTORS)) - 1;
			IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS, eics);
		} else {
			/* for legacy and MSI interrupts don't set any bits that
			 * are enabled for EIAM, because this operation would
			 * set *both* EIMS and EICS for any bit in EIAM */
			IXGBE_WRITE_REG(&adapter->hw, IXGBE_EICS,
				     (IXGBE_EICS_TCP_TIMER | IXGBE_EICS_OTHER));
		}
		/* Reset the timer */
		mod_timer(&adapter->watchdog_timer,
			  round_jiffies(jiffies + 2 * HZ));
	}
}

static int ixgbe_tso(struct ixgbe_adapter *adapter,
			 struct ixgbe_ring *tx_ring, struct sk_buff *skb,
			 u32 tx_flags, u8 *hdr_len)
{
	struct ixgbe_adv_tx_context_desc *context_desc;
	unsigned int i;
	int err;
	struct ixgbe_tx_buffer *tx_buffer_info;
	u32 vlan_macip_lens = 0, type_tucmd_mlhl = 0;
	u32 mss_l4len_idx = 0, l4len;

	if (skb_is_gso(skb)) {
		if (skb_header_cloned(skb)) {
			err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
			if (err)
				return err;
		}
		l4len = tcp_hdrlen(skb);
		*hdr_len += l4len;

		if (skb->protocol == htons(ETH_P_IP)) {
			struct iphdr *iph = ip_hdr(skb);
			iph->tot_len = 0;
			iph->check = 0;
			tcp_hdr(skb)->check = ~csum_tcpudp_magic(iph->saddr,
								 iph->daddr, 0,
								 IPPROTO_TCP,
								 0);
			adapter->hw_tso_ctxt++;
		} else if (skb_shinfo(skb)->gso_type == SKB_GSO_TCPV6) {
			ipv6_hdr(skb)->payload_len = 0;
			tcp_hdr(skb)->check =
			    ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
					     &ipv6_hdr(skb)->daddr,
					     0, IPPROTO_TCP, 0);
			adapter->hw_tso6_ctxt++;
		}

		i = tx_ring->next_to_use;

		tx_buffer_info = &tx_ring->tx_buffer_info[i];
		context_desc = IXGBE_TX_CTXTDESC_ADV(*tx_ring, i);

		/* VLAN MACLEN IPLEN */
		if (tx_flags & IXGBE_TX_FLAGS_VLAN)
			vlan_macip_lens |=
			    (tx_flags & IXGBE_TX_FLAGS_VLAN_MASK);
		vlan_macip_lens |= ((skb_network_offset(skb)) <<
				    IXGBE_ADVTXD_MACLEN_SHIFT);
		*hdr_len += skb_network_offset(skb);
		vlan_macip_lens |=
		    (skb_transport_header(skb) - skb_network_header(skb));
		*hdr_len +=
		    (skb_transport_header(skb) - skb_network_header(skb));
		context_desc->vlan_macip_lens = cpu_to_le32(vlan_macip_lens);
		context_desc->seqnum_seed = 0;

		/* ADV DTYP TUCMD MKRLOC/ISCSIHEDLEN */
		type_tucmd_mlhl |= (IXGBE_TXD_CMD_DEXT |
				    IXGBE_ADVTXD_DTYP_CTXT);

		if (skb->protocol == htons(ETH_P_IP))
			type_tucmd_mlhl |= IXGBE_ADVTXD_TUCMD_IPV4;
		type_tucmd_mlhl |= IXGBE_ADVTXD_TUCMD_L4T_TCP;
		context_desc->type_tucmd_mlhl = cpu_to_le32(type_tucmd_mlhl);

		/* MSS L4LEN IDX */
		mss_l4len_idx |=
		    (skb_shinfo(skb)->gso_size << IXGBE_ADVTXD_MSS_SHIFT);
		mss_l4len_idx |= (l4len << IXGBE_ADVTXD_L4LEN_SHIFT);
		context_desc->mss_l4len_idx = cpu_to_le32(mss_l4len_idx);

		tx_buffer_info->time_stamp = jiffies;
		tx_buffer_info->next_to_watch = i;

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

		return true;
	}
	return false;
}

static bool ixgbe_tx_csum(struct ixgbe_adapter *adapter,
				   struct ixgbe_ring *tx_ring,
				   struct sk_buff *skb, u32 tx_flags)
{
	struct ixgbe_adv_tx_context_desc *context_desc;
	unsigned int i;
	struct ixgbe_tx_buffer *tx_buffer_info;
	u32 vlan_macip_lens = 0, type_tucmd_mlhl = 0;

	if (skb->ip_summed == CHECKSUM_PARTIAL ||
	    (tx_flags & IXGBE_TX_FLAGS_VLAN)) {
		i = tx_ring->next_to_use;
		tx_buffer_info = &tx_ring->tx_buffer_info[i];
		context_desc = IXGBE_TX_CTXTDESC_ADV(*tx_ring, i);

		if (tx_flags & IXGBE_TX_FLAGS_VLAN)
			vlan_macip_lens |=
			    (tx_flags & IXGBE_TX_FLAGS_VLAN_MASK);
		vlan_macip_lens |= (skb_network_offset(skb) <<
				    IXGBE_ADVTXD_MACLEN_SHIFT);
		if (skb->ip_summed == CHECKSUM_PARTIAL)
			vlan_macip_lens |= (skb_transport_header(skb) -
					    skb_network_header(skb));

		context_desc->vlan_macip_lens = cpu_to_le32(vlan_macip_lens);
		context_desc->seqnum_seed = 0;

		type_tucmd_mlhl |= (IXGBE_TXD_CMD_DEXT |
				    IXGBE_ADVTXD_DTYP_CTXT);

		if (skb->ip_summed == CHECKSUM_PARTIAL) {
			switch (skb->protocol) {
			case __constant_htons(ETH_P_IP):
				type_tucmd_mlhl |= IXGBE_ADVTXD_TUCMD_IPV4;
				if (ip_hdr(skb)->protocol == IPPROTO_TCP)
					type_tucmd_mlhl |=
						IXGBE_ADVTXD_TUCMD_L4T_TCP;
				break;

			case __constant_htons(ETH_P_IPV6):
				/* XXX what about other V6 headers?? */
				if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
					type_tucmd_mlhl |=
						IXGBE_ADVTXD_TUCMD_L4T_TCP;
				break;

			default:
				if (unlikely(net_ratelimit())) {
					DPRINTK(PROBE, WARNING,
					 "partial checksum but proto=%x!\n",
					 skb->protocol);
				}
				break;
			}
		}

		context_desc->type_tucmd_mlhl = cpu_to_le32(type_tucmd_mlhl);
		context_desc->mss_l4len_idx = 0;

		tx_buffer_info->time_stamp = jiffies;
		tx_buffer_info->next_to_watch = i;
		adapter->hw_csum_tx_good++;
		i++;
		if (i == tx_ring->count)
			i = 0;
		tx_ring->next_to_use = i;

		return true;
	}
	return false;
}

static int ixgbe_tx_map(struct ixgbe_adapter *adapter,
			struct ixgbe_ring *tx_ring,
			struct sk_buff *skb, unsigned int first)
{
	struct ixgbe_tx_buffer *tx_buffer_info;
	unsigned int len = skb->len;
	unsigned int offset = 0, size, count = 0, i;
	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
	unsigned int f;

	len -= skb->data_len;

	i = tx_ring->next_to_use;

	while (len) {
		tx_buffer_info = &tx_ring->tx_buffer_info[i];
		size = min(len, (uint)IXGBE_MAX_DATA_PER_TXD);

		tx_buffer_info->length = size;
		tx_buffer_info->dma = pci_map_single(adapter->pdev,
						  skb->data + offset,
						  size, PCI_DMA_TODEVICE);
		tx_buffer_info->time_stamp = jiffies;
		tx_buffer_info->next_to_watch = i;

		len -= size;
		offset += size;
		count++;
		i++;
		if (i == tx_ring->count)
			i = 0;
	}

	for (f = 0; f < nr_frags; f++) {
		struct skb_frag_struct *frag;

		frag = &skb_shinfo(skb)->frags[f];
		len = frag->size;
		offset = frag->page_offset;

		while (len) {
			tx_buffer_info = &tx_ring->tx_buffer_info[i];
			size = min(len, (uint)IXGBE_MAX_DATA_PER_TXD);

			tx_buffer_info->length = size;
			tx_buffer_info->dma = pci_map_page(adapter->pdev,
							frag->page,
							offset,
							size, PCI_DMA_TODEVICE);
			tx_buffer_info->time_stamp = jiffies;
			tx_buffer_info->next_to_watch = i;

			len -= size;
			offset += size;
			count++;
			i++;
			if (i == tx_ring->count)
				i = 0;
		}
	}
	if (i == 0)
		i = tx_ring->count - 1;
	else
		i = i - 1;
	tx_ring->tx_buffer_info[i].skb = skb;
	tx_ring->tx_buffer_info[first].next_to_watch = i;

	return count;
}

static void ixgbe_tx_queue(struct ixgbe_adapter *adapter,
			       struct ixgbe_ring *tx_ring,
			       int tx_flags, int count, u32 paylen, u8 hdr_len)
{
	union ixgbe_adv_tx_desc *tx_desc = NULL;
	struct ixgbe_tx_buffer *tx_buffer_info;
	u32 olinfo_status = 0, cmd_type_len = 0;
	unsigned int i;
	u32 txd_cmd = IXGBE_TXD_CMD_EOP | IXGBE_TXD_CMD_RS | IXGBE_TXD_CMD_IFCS;

	cmd_type_len |= IXGBE_ADVTXD_DTYP_DATA;

	cmd_type_len |= IXGBE_ADVTXD_DCMD_IFCS | IXGBE_ADVTXD_DCMD_DEXT;

	if (tx_flags & IXGBE_TX_FLAGS_VLAN)
		cmd_type_len |= IXGBE_ADVTXD_DCMD_VLE;

	if (tx_flags & IXGBE_TX_FLAGS_TSO) {
		cmd_type_len |= IXGBE_ADVTXD_DCMD_TSE;

		olinfo_status |= IXGBE_TXD_POPTS_TXSM <<
						IXGBE_ADVTXD_POPTS_SHIFT;

		if (tx_flags & IXGBE_TX_FLAGS_IPV4)
			olinfo_status |= IXGBE_TXD_POPTS_IXSM <<
						IXGBE_ADVTXD_POPTS_SHIFT;

	} else if (tx_flags & IXGBE_TX_FLAGS_CSUM)
		olinfo_status |= IXGBE_TXD_POPTS_TXSM <<
						IXGBE_ADVTXD_POPTS_SHIFT;

	olinfo_status |= ((paylen - hdr_len) << IXGBE_ADVTXD_PAYLEN_SHIFT);

	i = tx_ring->next_to_use;
	while (count--) {
		tx_buffer_info = &tx_ring->tx_buffer_info[i];
		tx_desc = IXGBE_TX_DESC_ADV(*tx_ring, i);
		tx_desc->read.buffer_addr = cpu_to_le64(tx_buffer_info->dma);
		tx_desc->read.cmd_type_len =
			cpu_to_le32(cmd_type_len | tx_buffer_info->length);
		tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);

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

	tx_desc->read.cmd_type_len |= cpu_to_le32(txd_cmd);

	/*
	 * 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();

	tx_ring->next_to_use = i;
	writel(i, adapter->hw.hw_addr + tx_ring->tail);
}

static int __ixgbe_maybe_stop_tx(struct net_device *netdev,
				 struct ixgbe_ring *tx_ring, int size)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	netif_stop_subqueue(netdev, tx_ring->queue_index);
#else
	netif_stop_queue(netdev);
#endif
	/* Herbert's original patch had:
	 *  smp_mb__after_netif_stop_queue();
	 * but since that doesn't exist yet, just open code it. */
	smp_mb();

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

	/* A reprieve! - use start_queue because it doesn't call schedule */
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	netif_wake_subqueue(netdev, tx_ring->queue_index);
#else
	netif_wake_queue(netdev);
#endif
	++adapter->restart_queue;
	return 0;
}

static int ixgbe_maybe_stop_tx(struct net_device *netdev,
			       struct ixgbe_ring *tx_ring, int size)
{
	if (likely(IXGBE_DESC_UNUSED(tx_ring) >= size))
		return 0;
	return __ixgbe_maybe_stop_tx(netdev, tx_ring, size);
}


static int ixgbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	struct ixgbe_ring *tx_ring;
	unsigned int len = skb->len;
	unsigned int first;
	unsigned int tx_flags = 0;
	u8 hdr_len = 0;
	int r_idx = 0, tso;
	unsigned int mss = 0;
	int count = 0;
	unsigned int f;
	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
	len -= skb->data_len;
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	r_idx = (adapter->num_tx_queues - 1) & skb->queue_mapping;
#endif
	tx_ring = &adapter->tx_ring[r_idx];


	if (skb->len <= 0) {
		dev_kfree_skb(skb);
		return NETDEV_TX_OK;
	}
	mss = skb_shinfo(skb)->gso_size;

	if (mss)
		count++;
	else if (skb->ip_summed == CHECKSUM_PARTIAL)
		count++;

	count += TXD_USE_COUNT(len);
	for (f = 0; f < nr_frags; f++)
		count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);

	if (ixgbe_maybe_stop_tx(netdev, tx_ring, count)) {
		adapter->tx_busy++;
		return NETDEV_TX_BUSY;
	}
	if (adapter->vlgrp && vlan_tx_tag_present(skb)) {
		tx_flags |= IXGBE_TX_FLAGS_VLAN;
		tx_flags |= (vlan_tx_tag_get(skb) << IXGBE_TX_FLAGS_VLAN_SHIFT);
	}

	if (skb->protocol == htons(ETH_P_IP))
		tx_flags |= IXGBE_TX_FLAGS_IPV4;
	first = tx_ring->next_to_use;
	tso = ixgbe_tso(adapter, tx_ring, skb, tx_flags, &hdr_len);
	if (tso < 0) {
		dev_kfree_skb_any(skb);
		return NETDEV_TX_OK;
	}

	if (tso)
		tx_flags |= IXGBE_TX_FLAGS_TSO;
	else if (ixgbe_tx_csum(adapter, tx_ring, skb, tx_flags) &&
		 (skb->ip_summed == CHECKSUM_PARTIAL))
		tx_flags |= IXGBE_TX_FLAGS_CSUM;

	ixgbe_tx_queue(adapter, tx_ring, tx_flags,
			   ixgbe_tx_map(adapter, tx_ring, skb, first),
			   skb->len, hdr_len);

	netdev->trans_start = jiffies;

	ixgbe_maybe_stop_tx(netdev, tx_ring, DESC_NEEDED);

	return NETDEV_TX_OK;
}

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

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

/**
 * ixgbe_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 ixgbe_set_mac(struct net_device *netdev, void *p)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);
	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(adapter->hw.mac.addr, addr->sa_data, netdev->addr_len);

	ixgbe_set_rar(&adapter->hw, 0, adapter->hw.mac.addr, 0, IXGBE_RAH_AV);

	return 0;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
/*
 * Polling 'interrupt' - used by things like netconsole to send skbs
 * without having to re-enable interrupts. It's not called while
 * the interrupt routine is executing.
 */
static void ixgbe_netpoll(struct net_device *netdev)
{
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

	disable_irq(adapter->pdev->irq);
	adapter->flags |= IXGBE_FLAG_IN_NETPOLL;
	ixgbe_intr(adapter->pdev->irq, netdev);
	adapter->flags &= ~IXGBE_FLAG_IN_NETPOLL;
	enable_irq(adapter->pdev->irq);
}
#endif

/**
 * ixgbe_napi_add_all - prep napi structs for use
 * @adapter: private struct
 * helper function to napi_add each possible q_vector->napi
 */
static void ixgbe_napi_add_all(struct ixgbe_adapter *adapter)
{
	int i, q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
	int (*poll)(struct napi_struct *, int);

	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
		poll = &ixgbe_clean_rxonly;
	} else {
		poll = &ixgbe_poll;
		/* only one q_vector for legacy modes */
		q_vectors = 1;
	}

	for (i = 0; i < q_vectors; i++) {
		struct ixgbe_q_vector *q_vector = &adapter->q_vector[i];
		netif_napi_add(adapter->netdev, &q_vector->napi,
			       (*poll), 64);
	}
}

/**
 * ixgbe_probe - Device Initialization Routine
 * @pdev: PCI device information struct
 * @ent: entry in ixgbe_pci_tbl
 *
 * Returns 0 on success, negative on failure
 *
 * ixgbe_probe initializes an adapter identified by a pci_dev structure.
 * The OS initialization, configuring of the adapter private structure,
 * and a hardware reset occur.
 **/
static int __devinit ixgbe_probe(struct pci_dev *pdev,
				 const struct pci_device_id *ent)
{
	struct net_device *netdev;
	struct ixgbe_adapter *adapter = NULL;
	struct ixgbe_hw *hw;
	const struct ixgbe_info *ii = ixgbe_info_tbl[ent->driver_data];
	unsigned long mmio_start, mmio_len;
	static int cards_found;
	int i, err, pci_using_dac;
	u16 link_status, link_speed, link_width;
	u32 part_num;

	err = pci_enable_device(pdev);
	if (err)
		return err;

	if (!pci_set_dma_mask(pdev, DMA_64BIT_MASK) &&
	    !pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK)) {
		pci_using_dac = 1;
	} else {
		err = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
		if (err) {
			err = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
			if (err) {
				dev_err(&pdev->dev, "No usable DMA "
					"configuration, aborting\n");
				goto err_dma;
			}
		}
		pci_using_dac = 0;
	}

	err = pci_request_regions(pdev, ixgbe_driver_name);
	if (err) {
		dev_err(&pdev->dev, "pci_request_regions failed 0x%x\n", err);
		goto err_pci_reg;
	}

	pci_set_master(pdev);
	pci_save_state(pdev);

#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	netdev = alloc_etherdev_mq(sizeof(struct ixgbe_adapter), MAX_TX_QUEUES);
#else
	netdev = alloc_etherdev(sizeof(struct ixgbe_adapter));
#endif
	if (!netdev) {
		err = -ENOMEM;
		goto err_alloc_etherdev;
	}

	SET_NETDEV_DEV(netdev, &pdev->dev);

	pci_set_drvdata(pdev, netdev);
	adapter = netdev_priv(netdev);

	adapter->netdev = netdev;
	adapter->pdev = pdev;
	hw = &adapter->hw;
	hw->back = adapter;
	adapter->msg_enable = (1 << DEFAULT_DEBUG_LEVEL_SHIFT) - 1;

	mmio_start = pci_resource_start(pdev, 0);
	mmio_len = pci_resource_len(pdev, 0);

	hw->hw_addr = ioremap(mmio_start, mmio_len);
	if (!hw->hw_addr) {
		err = -EIO;
		goto err_ioremap;
	}

	for (i = 1; i <= 5; i++) {
		if (pci_resource_len(pdev, i) == 0)
			continue;
	}

	netdev->open = &ixgbe_open;
	netdev->stop = &ixgbe_close;
	netdev->hard_start_xmit = &ixgbe_xmit_frame;
	netdev->get_stats = &ixgbe_get_stats;
	netdev->set_multicast_list = &ixgbe_set_multi;
	netdev->set_mac_address = &ixgbe_set_mac;
	netdev->change_mtu = &ixgbe_change_mtu;
	ixgbe_set_ethtool_ops(netdev);
	netdev->tx_timeout = &ixgbe_tx_timeout;
	netdev->watchdog_timeo = 5 * HZ;
	netdev->vlan_rx_register = ixgbe_vlan_rx_register;
	netdev->vlan_rx_add_vid = ixgbe_vlan_rx_add_vid;
	netdev->vlan_rx_kill_vid = ixgbe_vlan_rx_kill_vid;
#ifdef CONFIG_NET_POLL_CONTROLLER
	netdev->poll_controller = ixgbe_netpoll;
#endif
	strcpy(netdev->name, pci_name(pdev));

	netdev->mem_start = mmio_start;
	netdev->mem_end = mmio_start + mmio_len;

	adapter->bd_number = cards_found;

	/* PCI config space info */
	hw->vendor_id = pdev->vendor;
	hw->device_id = pdev->device;
	hw->revision_id = pdev->revision;
	hw->subsystem_vendor_id = pdev->subsystem_vendor;
	hw->subsystem_device_id = pdev->subsystem_device;

	/* Setup hw api */
	memcpy(&hw->mac.ops, ii->mac_ops, sizeof(hw->mac.ops));
	hw->mac.type  = ii->mac;

	err = ii->get_invariants(hw);
	if (err)
		goto err_hw_init;

	/* setup the private structure */
	err = ixgbe_sw_init(adapter);
	if (err)
		goto err_sw_init;

	netdev->features = NETIF_F_SG |
			   NETIF_F_HW_CSUM |
			   NETIF_F_HW_VLAN_TX |
			   NETIF_F_HW_VLAN_RX |
			   NETIF_F_HW_VLAN_FILTER;

	netdev->features |= NETIF_F_TSO;

	netdev->features |= NETIF_F_TSO6;
	if (pci_using_dac)
		netdev->features |= NETIF_F_HIGHDMA;

#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	netdev->features |= NETIF_F_MULTI_QUEUE;
#endif

	/* make sure the EEPROM is good */
	if (ixgbe_validate_eeprom_checksum(hw, NULL) < 0) {
		dev_err(&pdev->dev, "The EEPROM Checksum Is Not Valid\n");
		err = -EIO;
		goto err_eeprom;
	}

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

	if (ixgbe_validate_mac_addr(netdev->dev_addr)) {
		err = -EIO;
		goto err_eeprom;
	}

	init_timer(&adapter->watchdog_timer);
	adapter->watchdog_timer.function = &ixgbe_watchdog;
	adapter->watchdog_timer.data = (unsigned long)adapter;

	INIT_WORK(&adapter->reset_task, ixgbe_reset_task);

	/* initialize default flow control settings */
	hw->fc.original_type = ixgbe_fc_full;
	hw->fc.type = ixgbe_fc_full;
	hw->fc.high_water = IXGBE_DEFAULT_FCRTH;
	hw->fc.low_water = IXGBE_DEFAULT_FCRTL;
	hw->fc.pause_time = IXGBE_DEFAULT_FCPAUSE;

	err = ixgbe_init_interrupt_scheme(adapter);
	if (err)
		goto err_sw_init;

	/* print bus type/speed/width info */
	pci_read_config_word(pdev, IXGBE_PCI_LINK_STATUS, &link_status);
	link_speed = link_status & IXGBE_PCI_LINK_SPEED;
	link_width = link_status & IXGBE_PCI_LINK_WIDTH;
	dev_info(&pdev->dev, "(PCI Express:%s:%s) "
		 "%02x:%02x:%02x:%02x:%02x:%02x\n",
		((link_speed == IXGBE_PCI_LINK_SPEED_5000) ? "5.0Gb/s" :
		 (link_speed == IXGBE_PCI_LINK_SPEED_2500) ? "2.5Gb/s" :
		 "Unknown"),
		((link_width == IXGBE_PCI_LINK_WIDTH_8) ? "Width x8" :
		 (link_width == IXGBE_PCI_LINK_WIDTH_4) ? "Width x4" :
		 (link_width == IXGBE_PCI_LINK_WIDTH_2) ? "Width x2" :
		 (link_width == IXGBE_PCI_LINK_WIDTH_1) ? "Width x1" :
		 "Unknown"),
		netdev->dev_addr[0], netdev->dev_addr[1], netdev->dev_addr[2],
		netdev->dev_addr[3], netdev->dev_addr[4], netdev->dev_addr[5]);
	ixgbe_read_part_num(hw, &part_num);
	dev_info(&pdev->dev, "MAC: %d, PHY: %d, PBA No: %06x-%03x\n",
		 hw->mac.type, hw->phy.type,
		 (part_num >> 8), (part_num & 0xff));

	if (link_width <= IXGBE_PCI_LINK_WIDTH_4) {
		dev_warn(&pdev->dev, "PCI-Express bandwidth available for "
			 "this card is not sufficient for optimal "
			 "performance.\n");
		dev_warn(&pdev->dev, "For optimal performance a x8 "
			 "PCI-Express slot is required.\n");
	}

	/* reset the hardware with the new settings */
	ixgbe_start_hw(hw);

	netif_carrier_off(netdev);
	netif_stop_queue(netdev);
#ifdef CONFIG_NETDEVICES_MULTIQUEUE
	for (i = 0; i < adapter->num_tx_queues; i++)
		netif_stop_subqueue(netdev, i);
#endif

	ixgbe_napi_add_all(adapter);

	strcpy(netdev->name, "eth%d");
	err = register_netdev(netdev);
	if (err)
		goto err_register;

#ifdef CONFIG_DCA
	if (dca_add_requester(&pdev->dev) == 0) {
		adapter->flags |= IXGBE_FLAG_DCA_ENABLED;
		/* always use CB2 mode, difference is masked
		 * in the CB driver */
		IXGBE_WRITE_REG(hw, IXGBE_DCA_CTRL, 2);
		ixgbe_setup_dca(adapter);
	}
#endif

	dev_info(&pdev->dev, "Intel(R) 10 Gigabit Network Connection\n");
	cards_found++;
	return 0;

err_register:
	ixgbe_release_hw_control(adapter);
err_hw_init:
err_sw_init:
	ixgbe_reset_interrupt_capability(adapter);
err_eeprom:
	iounmap(hw->hw_addr);
err_ioremap:
	free_netdev(netdev);
err_alloc_etherdev:
	pci_release_regions(pdev);
err_pci_reg:
err_dma:
	pci_disable_device(pdev);
	return err;
}

/**
 * ixgbe_remove - Device Removal Routine
 * @pdev: PCI device information struct
 *
 * ixgbe_remove is called by the PCI subsystem to alert the driver
 * that it should release a PCI device.  The could be caused by a
 * Hot-Plug event, or because the driver is going to be removed from
 * memory.
 **/
static void __devexit ixgbe_remove(struct pci_dev *pdev)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct ixgbe_adapter *adapter = netdev_priv(netdev);

	set_bit(__IXGBE_DOWN, &adapter->state);
	del_timer_sync(&adapter->watchdog_timer);

	flush_scheduled_work();

#ifdef CONFIG_DCA
	if (adapter->flags & IXGBE_FLAG_DCA_ENABLED) {
		adapter->flags &= ~IXGBE_FLAG_DCA_ENABLED;
		dca_remove_requester(&pdev->dev);
		IXGBE_WRITE_REG(&adapter->hw, IXGBE_DCA_CTRL, 1);
	}

#endif
	unregister_netdev(netdev);

	ixgbe_reset_interrupt_capability(adapter);

	ixgbe_release_hw_control(adapter);

	iounmap(adapter->hw.hw_addr);
	pci_release_regions(pdev);

	DPRINTK(PROBE, INFO, "complete\n");
	kfree(adapter->tx_ring);
	kfree(adapter->rx_ring);

	free_netdev(netdev);

	pci_disable_device(pdev);
}

/**
 * ixgbe_io_error_detected - called when PCI error is detected
 * @pdev: Pointer to PCI device
 * @state: The current pci connection state
 *
 * This function is called after a PCI bus error affecting
 * this device has been detected.
 */
static pci_ers_result_t ixgbe_io_error_detected(struct pci_dev *pdev,
						pci_channel_state_t state)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct ixgbe_adapter *adapter = netdev->priv;

	netif_device_detach(netdev);

	if (netif_running(netdev))
		ixgbe_down(adapter);
	pci_disable_device(pdev);

	/* Request a slot slot reset. */
	return PCI_ERS_RESULT_NEED_RESET;
}

/**
 * ixgbe_io_slot_reset - called after the pci bus has been reset.
 * @pdev: Pointer to PCI device
 *
 * Restart the card from scratch, as if from a cold-boot.
 */
static pci_ers_result_t ixgbe_io_slot_reset(struct pci_dev *pdev)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct ixgbe_adapter *adapter = netdev->priv;

	if (pci_enable_device(pdev)) {
		DPRINTK(PROBE, ERR,
			"Cannot re-enable PCI device after reset.\n");
		return PCI_ERS_RESULT_DISCONNECT;
	}
	pci_set_master(pdev);
	pci_restore_state(pdev);

	pci_enable_wake(pdev, PCI_D3hot, 0);
	pci_enable_wake(pdev, PCI_D3cold, 0);

	ixgbe_reset(adapter);

	return PCI_ERS_RESULT_RECOVERED;
}

/**
 * ixgbe_io_resume - called when traffic can start flowing again.
 * @pdev: Pointer to PCI device
 *
 * This callback is called when the error recovery driver tells us that
 * its OK to resume normal operation.
 */
static void ixgbe_io_resume(struct pci_dev *pdev)
{
	struct net_device *netdev = pci_get_drvdata(pdev);
	struct ixgbe_adapter *adapter = netdev->priv;

	if (netif_running(netdev)) {
		if (ixgbe_up(adapter)) {
			DPRINTK(PROBE, INFO, "ixgbe_up failed after reset\n");
			return;
		}
	}

	netif_device_attach(netdev);

}

static struct pci_error_handlers ixgbe_err_handler = {
	.error_detected = ixgbe_io_error_detected,
	.slot_reset = ixgbe_io_slot_reset,
	.resume = ixgbe_io_resume,
};

static struct pci_driver ixgbe_driver = {
	.name     = ixgbe_driver_name,
	.id_table = ixgbe_pci_tbl,
	.probe    = ixgbe_probe,
	.remove   = __devexit_p(ixgbe_remove),
#ifdef CONFIG_PM
	.suspend  = ixgbe_suspend,
	.resume   = ixgbe_resume,
#endif
	.shutdown = ixgbe_shutdown,
	.err_handler = &ixgbe_err_handler
};

/**
 * ixgbe_init_module - Driver Registration Routine
 *
 * ixgbe_init_module is the first routine called when the driver is
 * loaded. All it does is register with the PCI subsystem.
 **/
static int __init ixgbe_init_module(void)
{
	int ret;
	printk(KERN_INFO "%s: %s - version %s\n", ixgbe_driver_name,
	       ixgbe_driver_string, ixgbe_driver_version);

	printk(KERN_INFO "%s: %s\n", ixgbe_driver_name, ixgbe_copyright);

#ifdef CONFIG_DCA
	dca_register_notify(&dca_notifier);

#endif
	ret = pci_register_driver(&ixgbe_driver);
	return ret;
}
module_init(ixgbe_init_module);

/**
 * ixgbe_exit_module - Driver Exit Cleanup Routine
 *
 * ixgbe_exit_module is called just before the driver is removed
 * from memory.
 **/
static void __exit ixgbe_exit_module(void)
{
#ifdef CONFIG_DCA
	dca_unregister_notify(&dca_notifier);
#endif
	pci_unregister_driver(&ixgbe_driver);
}

#ifdef CONFIG_DCA
static int ixgbe_notify_dca(struct notifier_block *nb, unsigned long event,
			    void *p)
{
	int ret_val;

	ret_val = driver_for_each_device(&ixgbe_driver.driver, NULL, &event,
					 __ixgbe_notify_dca);

	return ret_val ? NOTIFY_BAD : NOTIFY_DONE;
}
#endif /* CONFIG_DCA */

module_exit(ixgbe_exit_module);

/* ixgbe_main.c */