[safe/jmp/linux-2.6] / drivers / net / e1000 / e1000_main.c

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

  Intel PRO/1000 Linux driver
  Copyright(c) 1999 - 2006 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 "e1000.h"
#include <net/ip6_checksum.h>

char e1000_driver_name[] = "e1000";
static char e1000_driver_string[] = "Intel(R) PRO/1000 Network Driver";
#define DRV_VERSION "7.3.21-k5-NAPI"
const char e1000_driver_version[] = DRV_VERSION;
static const char e1000_copyright[] = "Copyright (c) 1999-2006 Intel Corporation.";

/* e1000_pci_tbl - PCI Device ID Table
 *
 * Last entry must be all 0s
 *
 * Macro expands to...
 *   {PCI_DEVICE(PCI_VENDOR_ID_INTEL, device_id)}
 */
static struct pci_device_id e1000_pci_tbl[] = {
        INTEL_E1000_ETHERNET_DEVICE(0x1000),
        INTEL_E1000_ETHERNET_DEVICE(0x1001),
        INTEL_E1000_ETHERNET_DEVICE(0x1004),
        INTEL_E1000_ETHERNET_DEVICE(0x1008),
        INTEL_E1000_ETHERNET_DEVICE(0x1009),
        INTEL_E1000_ETHERNET_DEVICE(0x100C),
        INTEL_E1000_ETHERNET_DEVICE(0x100D),
        INTEL_E1000_ETHERNET_DEVICE(0x100E),
        INTEL_E1000_ETHERNET_DEVICE(0x100F),
        INTEL_E1000_ETHERNET_DEVICE(0x1010),
        INTEL_E1000_ETHERNET_DEVICE(0x1011),
        INTEL_E1000_ETHERNET_DEVICE(0x1012),
        INTEL_E1000_ETHERNET_DEVICE(0x1013),
        INTEL_E1000_ETHERNET_DEVICE(0x1014),
        INTEL_E1000_ETHERNET_DEVICE(0x1015),
        INTEL_E1000_ETHERNET_DEVICE(0x1016),
        INTEL_E1000_ETHERNET_DEVICE(0x1017),
        INTEL_E1000_ETHERNET_DEVICE(0x1018),
        INTEL_E1000_ETHERNET_DEVICE(0x1019),
        INTEL_E1000_ETHERNET_DEVICE(0x101A),
        INTEL_E1000_ETHERNET_DEVICE(0x101D),
        INTEL_E1000_ETHERNET_DEVICE(0x101E),
        INTEL_E1000_ETHERNET_DEVICE(0x1026),
        INTEL_E1000_ETHERNET_DEVICE(0x1027),
        INTEL_E1000_ETHERNET_DEVICE(0x1028),
        INTEL_E1000_ETHERNET_DEVICE(0x1075),
        INTEL_E1000_ETHERNET_DEVICE(0x1076),
        INTEL_E1000_ETHERNET_DEVICE(0x1077),
        INTEL_E1000_ETHERNET_DEVICE(0x1078),
        INTEL_E1000_ETHERNET_DEVICE(0x1079),
        INTEL_E1000_ETHERNET_DEVICE(0x107A),
        INTEL_E1000_ETHERNET_DEVICE(0x107B),
        INTEL_E1000_ETHERNET_DEVICE(0x107C),
        INTEL_E1000_ETHERNET_DEVICE(0x108A),
        INTEL_E1000_ETHERNET_DEVICE(0x1099),
        INTEL_E1000_ETHERNET_DEVICE(0x10B5),
        /* required last entry */
        {0,}
};

MODULE_DEVICE_TABLE(pci, e1000_pci_tbl);

int e1000_up(struct e1000_adapter *adapter);
void e1000_down(struct e1000_adapter *adapter);
void e1000_reinit_locked(struct e1000_adapter *adapter);
void e1000_reset(struct e1000_adapter *adapter);
int e1000_set_spd_dplx(struct e1000_adapter *adapter, u16 spddplx);
int e1000_setup_all_tx_resources(struct e1000_adapter *adapter);
int e1000_setup_all_rx_resources(struct e1000_adapter *adapter);
void e1000_free_all_tx_resources(struct e1000_adapter *adapter);
void e1000_free_all_rx_resources(struct e1000_adapter *adapter);
static int e1000_setup_tx_resources(struct e1000_adapter *adapter,
                             struct e1000_tx_ring *txdr);
static int e1000_setup_rx_resources(struct e1000_adapter *adapter,
                             struct e1000_rx_ring *rxdr);
static void e1000_free_tx_resources(struct e1000_adapter *adapter,
                             struct e1000_tx_ring *tx_ring);
static void e1000_free_rx_resources(struct e1000_adapter *adapter,
                             struct e1000_rx_ring *rx_ring);
void e1000_update_stats(struct e1000_adapter *adapter);

static int e1000_init_module(void);
static void e1000_exit_module(void);
static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
static void __devexit e1000_remove(struct pci_dev *pdev);
static int e1000_alloc_queues(struct e1000_adapter *adapter);
static int e1000_sw_init(struct e1000_adapter *adapter);
static int e1000_open(struct net_device *netdev);
static int e1000_close(struct net_device *netdev);
static void e1000_configure_tx(struct e1000_adapter *adapter);
static void e1000_configure_rx(struct e1000_adapter *adapter);
static void e1000_setup_rctl(struct e1000_adapter *adapter);
static void e1000_clean_all_tx_rings(struct e1000_adapter *adapter);
static void e1000_clean_all_rx_rings(struct e1000_adapter *adapter);
static void e1000_clean_tx_ring(struct e1000_adapter *adapter,
                                struct e1000_tx_ring *tx_ring);
static void e1000_clean_rx_ring(struct e1000_adapter *adapter,
                                struct e1000_rx_ring *rx_ring);
static void e1000_set_rx_mode(struct net_device *netdev);
static void e1000_update_phy_info(unsigned long data);
static void e1000_watchdog(unsigned long data);
static void e1000_82547_tx_fifo_stall(unsigned long data);
static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
                                    struct net_device *netdev);
static struct net_device_stats * e1000_get_stats(struct net_device *netdev);
static int e1000_change_mtu(struct net_device *netdev, int new_mtu);
static int e1000_set_mac(struct net_device *netdev, void *p);
static irqreturn_t e1000_intr(int irq, void *data);
static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
                               struct e1000_tx_ring *tx_ring);
static int e1000_clean(struct napi_struct *napi, int budget);
static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
                               struct e1000_rx_ring *rx_ring,
                               int *work_done, int work_to_do);
static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
                                     struct e1000_rx_ring *rx_ring,
                                     int *work_done, int work_to_do);
static void e1000_alloc_rx_buffers(struct e1000_adapter *adapter,
                                   struct e1000_rx_ring *rx_ring,
                                   int cleaned_count);
static void e1000_alloc_jumbo_rx_buffers(struct e1000_adapter *adapter,
                                         struct e1000_rx_ring *rx_ring,
                                         int cleaned_count);
static int e1000_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd);
static int e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr,
                           int cmd);
static void e1000_enter_82542_rst(struct e1000_adapter *adapter);
static void e1000_leave_82542_rst(struct e1000_adapter *adapter);
static void e1000_tx_timeout(struct net_device *dev);
static void e1000_reset_task(struct work_struct *work);
static void e1000_smartspeed(struct e1000_adapter *adapter);
static int e1000_82547_fifo_workaround(struct e1000_adapter *adapter,
                                       struct sk_buff *skb);

static void e1000_vlan_rx_register(struct net_device *netdev, struct vlan_group *grp);
static void e1000_vlan_rx_add_vid(struct net_device *netdev, u16 vid);
static void e1000_vlan_rx_kill_vid(struct net_device *netdev, u16 vid);
static void e1000_restore_vlan(struct e1000_adapter *adapter);

#ifdef CONFIG_PM
static int e1000_suspend(struct pci_dev *pdev, pm_message_t state);
static int e1000_resume(struct pci_dev *pdev);
#endif
static void e1000_shutdown(struct pci_dev *pdev);

#ifdef CONFIG_NET_POLL_CONTROLLER
/* for netdump / net console */
static void e1000_netpoll (struct net_device *netdev);
#endif

#define COPYBREAK_DEFAULT 256
static unsigned int copybreak __read_mostly = COPYBREAK_DEFAULT;
module_param(copybreak, uint, 0644);
MODULE_PARM_DESC(copybreak,
        "Maximum size of packet that is copied to a new buffer on receive");

static pci_ers_result_t e1000_io_error_detected(struct pci_dev *pdev,
                     pci_channel_state_t state);
static pci_ers_result_t e1000_io_slot_reset(struct pci_dev *pdev);
static void e1000_io_resume(struct pci_dev *pdev);

static struct pci_error_handlers e1000_err_handler = {
        .error_detected = e1000_io_error_detected,
        .slot_reset = e1000_io_slot_reset,
        .resume = e1000_io_resume,
};

static struct pci_driver e1000_driver = {
        .name     = e1000_driver_name,
        .id_table = e1000_pci_tbl,
        .probe    = e1000_probe,
        .remove   = __devexit_p(e1000_remove),
#ifdef CONFIG_PM
        /* Power Managment Hooks */
        .suspend  = e1000_suspend,
        .resume   = e1000_resume,
#endif
        .shutdown = e1000_shutdown,
        .err_handler = &e1000_err_handler
};

MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
MODULE_DESCRIPTION("Intel(R) PRO/1000 Network Driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

static int debug = NETIF_MSG_DRV | NETIF_MSG_PROBE;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

/**
 * e1000_init_module - Driver Registration Routine
 *
 * e1000_init_module is the first routine called when the driver is
 * loaded. All it does is register with the PCI subsystem.
 **/

static int __init e1000_init_module(void)
{
        int ret;
        printk(KERN_INFO "%s - version %s\n",
               e1000_driver_string, e1000_driver_version);

        printk(KERN_INFO "%s\n", e1000_copyright);

        ret = pci_register_driver(&e1000_driver);
        if (copybreak != COPYBREAK_DEFAULT) {
                if (copybreak == 0)
                        printk(KERN_INFO "e1000: copybreak disabled\n");
                else
                        printk(KERN_INFO "e1000: copybreak enabled for "
                               "packets <= %u bytes\n", copybreak);
        }
        return ret;
}

module_init(e1000_init_module);

/**
 * e1000_exit_module - Driver Exit Cleanup Routine
 *
 * e1000_exit_module is called just before the driver is removed
 * from memory.
 **/

static void __exit e1000_exit_module(void)
{
        pci_unregister_driver(&e1000_driver);
}

module_exit(e1000_exit_module);

static int e1000_request_irq(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        irq_handler_t handler = e1000_intr;
        int irq_flags = IRQF_SHARED;
        int err;

        err = request_irq(adapter->pdev->irq, handler, irq_flags, netdev->name,
                          netdev);
        if (err) {
                DPRINTK(PROBE, ERR,
                        "Unable to allocate interrupt Error: %d\n", err);
        }

        return err;
}

static void e1000_free_irq(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;

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

/**
 * e1000_irq_disable - Mask off interrupt generation on the NIC
 * @adapter: board private structure
 **/

static void e1000_irq_disable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        ew32(IMC, ~0);
        E1000_WRITE_FLUSH();
        synchronize_irq(adapter->pdev->irq);
}

/**
 * e1000_irq_enable - Enable default interrupt generation settings
 * @adapter: board private structure
 **/

static void e1000_irq_enable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        ew32(IMS, IMS_ENABLE_MASK);
        E1000_WRITE_FLUSH();
}

static void e1000_update_mng_vlan(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        u16 vid = hw->mng_cookie.vlan_id;
        u16 old_vid = adapter->mng_vlan_id;
        if (adapter->vlgrp) {
                if (!vlan_group_get_device(adapter->vlgrp, vid)) {
                        if (hw->mng_cookie.status &
                                E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT) {
                                e1000_vlan_rx_add_vid(netdev, vid);
                                adapter->mng_vlan_id = vid;
                        } else
                                adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;

                        if ((old_vid != (u16)E1000_MNG_VLAN_NONE) &&
                                        (vid != old_vid) &&
                            !vlan_group_get_device(adapter->vlgrp, old_vid))
                                e1000_vlan_rx_kill_vid(netdev, old_vid);
                } else
                        adapter->mng_vlan_id = vid;
        }
}

static void e1000_init_manageability(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        if (adapter->en_mng_pt) {
                u32 manc = er32(MANC);

                /* disable hardware interception of ARP */
                manc &= ~(E1000_MANC_ARP_EN);

                ew32(MANC, manc);
        }
}

static void e1000_release_manageability(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        if (adapter->en_mng_pt) {
                u32 manc = er32(MANC);

                /* re-enable hardware interception of ARP */
                manc |= E1000_MANC_ARP_EN;

                ew32(MANC, manc);
        }
}

/**
 * e1000_configure - configure the hardware for RX and TX
 * @adapter = private board structure
 **/
static void e1000_configure(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int i;

        e1000_set_rx_mode(netdev);

        e1000_restore_vlan(adapter);
        e1000_init_manageability(adapter);

        e1000_configure_tx(adapter);
        e1000_setup_rctl(adapter);
        e1000_configure_rx(adapter);
        /* call E1000_DESC_UNUSED which always leaves
         * at least 1 descriptor unused to make sure
         * next_to_use != next_to_clean */
        for (i = 0; i < adapter->num_rx_queues; i++) {
                struct e1000_rx_ring *ring = &adapter->rx_ring[i];
                adapter->alloc_rx_buf(adapter, ring,
                                      E1000_DESC_UNUSED(ring));
        }

        adapter->tx_queue_len = netdev->tx_queue_len;
}

int e1000_up(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        /* hardware has been reset, we need to reload some things */
        e1000_configure(adapter);

        clear_bit(__E1000_DOWN, &adapter->flags);

        napi_enable(&adapter->napi);

        e1000_irq_enable(adapter);

        netif_wake_queue(adapter->netdev);

        /* fire a link change interrupt to start the watchdog */
        ew32(ICS, E1000_ICS_LSC);
        return 0;
}

/**
 * e1000_power_up_phy - restore link in case the phy was powered down
 * @adapter: address of board private structure
 *
 * The phy may be powered down to save power and turn off link when the
 * driver is unloaded and wake on lan is not enabled (among others)
 * *** this routine MUST be followed by a call to e1000_reset ***
 *
 **/

void e1000_power_up_phy(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u16 mii_reg = 0;

        /* Just clear the power down bit to wake the phy back up */
        if (hw->media_type == e1000_media_type_copper) {
                /* according to the manual, the phy will retain its
                 * settings across a power-down/up cycle */
                e1000_read_phy_reg(hw, PHY_CTRL, &mii_reg);
                mii_reg &= ~MII_CR_POWER_DOWN;
                e1000_write_phy_reg(hw, PHY_CTRL, mii_reg);
        }
}

static void e1000_power_down_phy(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        /* Power down the PHY so no link is implied when interface is down *
         * The PHY cannot be powered down if any of the following is true *
         * (a) WoL is enabled
         * (b) AMT is active
         * (c) SoL/IDER session is active */
        if (!adapter->wol && hw->mac_type >= e1000_82540 &&
           hw->media_type == e1000_media_type_copper) {
                u16 mii_reg = 0;

                switch (hw->mac_type) {
                case e1000_82540:
                case e1000_82545:
                case e1000_82545_rev_3:
                case e1000_82546:
                case e1000_82546_rev_3:
                case e1000_82541:
                case e1000_82541_rev_2:
                case e1000_82547:
                case e1000_82547_rev_2:
                        if (er32(MANC) & E1000_MANC_SMBUS_EN)
                                goto out;
                        break;
                default:
                        goto out;
                }
                e1000_read_phy_reg(hw, PHY_CTRL, &mii_reg);
                mii_reg |= MII_CR_POWER_DOWN;
                e1000_write_phy_reg(hw, PHY_CTRL, mii_reg);
                mdelay(1);
        }
out:
        return;
}

void e1000_down(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        u32 rctl, tctl;

        /* signal that we're down so the interrupt handler does not
         * reschedule our watchdog timer */
        set_bit(__E1000_DOWN, &adapter->flags);

        /* disable receives in the hardware */
        rctl = er32(RCTL);
        ew32(RCTL, rctl & ~E1000_RCTL_EN);
        /* flush and sleep below */

        /* can be netif_tx_disable when NETIF_F_LLTX is removed */
        netif_stop_queue(netdev);

        /* disable transmits in the hardware */
        tctl = er32(TCTL);
        tctl &= ~E1000_TCTL_EN;
        ew32(TCTL, tctl);
        /* flush both disables and wait for them to finish */
        E1000_WRITE_FLUSH();
        msleep(10);

        napi_disable(&adapter->napi);

        e1000_irq_disable(adapter);

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

        netdev->tx_queue_len = adapter->tx_queue_len;
        adapter->link_speed = 0;
        adapter->link_duplex = 0;
        netif_carrier_off(netdev);

        e1000_reset(adapter);
        e1000_clean_all_tx_rings(adapter);
        e1000_clean_all_rx_rings(adapter);
}

void e1000_reinit_locked(struct e1000_adapter *adapter)
{
        WARN_ON(in_interrupt());
        while (test_and_set_bit(__E1000_RESETTING, &adapter->flags))
                msleep(1);
        e1000_down(adapter);
        e1000_up(adapter);
        clear_bit(__E1000_RESETTING, &adapter->flags);
}

void e1000_reset(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 pba = 0, tx_space, min_tx_space, min_rx_space;
        bool legacy_pba_adjust = false;
        u16 hwm;

        /* Repartition Pba for greater than 9k mtu
         * To take effect CTRL.RST is required.
         */

        switch (hw->mac_type) {
        case e1000_82542_rev2_0:
        case e1000_82542_rev2_1:
        case e1000_82543:
        case e1000_82544:
        case e1000_82540:
        case e1000_82541:
        case e1000_82541_rev_2:
                legacy_pba_adjust = true;
                pba = E1000_PBA_48K;
                break;
        case e1000_82545:
        case e1000_82545_rev_3:
        case e1000_82546:
        case e1000_82546_rev_3:
                pba = E1000_PBA_48K;
                break;
        case e1000_82547:
        case e1000_82547_rev_2:
                legacy_pba_adjust = true;
                pba = E1000_PBA_30K;
                break;
        case e1000_undefined:
        case e1000_num_macs:
                break;
        }

        if (legacy_pba_adjust) {
                if (hw->max_frame_size > E1000_RXBUFFER_8192)
                        pba -= 8; /* allocate more FIFO for Tx */

                if (hw->mac_type == e1000_82547) {
                        adapter->tx_fifo_head = 0;
                        adapter->tx_head_addr = pba << E1000_TX_HEAD_ADDR_SHIFT;
                        adapter->tx_fifo_size =
                                (E1000_PBA_40K - pba) << E1000_PBA_BYTES_SHIFT;
                        atomic_set(&adapter->tx_fifo_stall, 0);
                }
        } else if (hw->max_frame_size >  ETH_FRAME_LEN + ETH_FCS_LEN) {
                /* adjust PBA for jumbo frames */
                ew32(PBA, pba);

                /* To maintain wire speed transmits, the Tx FIFO should be
                 * large enough to accommodate two full transmit packets,
                 * rounded up to the next 1KB and expressed in KB.  Likewise,
                 * the Rx FIFO should be large enough to accommodate at least
                 * one full receive packet and is similarly rounded up and
                 * expressed in KB. */
                pba = er32(PBA);
                /* upper 16 bits has Tx packet buffer allocation size in KB */
                tx_space = pba >> 16;
                /* lower 16 bits has Rx packet buffer allocation size in KB */
                pba &= 0xffff;
                /*
                 * the tx fifo also stores 16 bytes of information about the tx
                 * but don't include ethernet FCS because hardware appends it
                 */
                min_tx_space = (hw->max_frame_size +
                                sizeof(struct e1000_tx_desc) -
                                ETH_FCS_LEN) * 2;
                min_tx_space = ALIGN(min_tx_space, 1024);
                min_tx_space >>= 10;
                /* software strips receive CRC, so leave room for it */
                min_rx_space = hw->max_frame_size;
                min_rx_space = ALIGN(min_rx_space, 1024);
                min_rx_space >>= 10;

                /* If current Tx allocation is less than the min Tx FIFO size,
                 * and the min Tx FIFO size is less than the current Rx FIFO
                 * allocation, take space away from current Rx allocation */
                if (tx_space < min_tx_space &&
                    ((min_tx_space - tx_space) < pba)) {
                        pba = pba - (min_tx_space - tx_space);

                        /* PCI/PCIx hardware has PBA alignment constraints */
                        switch (hw->mac_type) {
                        case e1000_82545 ... e1000_82546_rev_3:
                                pba &= ~(E1000_PBA_8K - 1);
                                break;
                        default:
                                break;
                        }

                        /* if short on rx space, rx wins and must trump tx
                         * adjustment or use Early Receive if available */
                        if (pba < min_rx_space)
                                pba = min_rx_space;
                }
        }

        ew32(PBA, pba);

        /*
         * flow control settings:
         * The high water mark must be low enough to fit one full frame
         * (or the size used for early receive) above it in the Rx FIFO.
         * Set it to the lower of:
         * - 90% of the Rx FIFO size, and
         * - the full Rx FIFO size minus the early receive size (for parts
         *   with ERT support assuming ERT set to E1000_ERT_2048), or
         * - the full Rx FIFO size minus one full frame
         */
        hwm = min(((pba << 10) * 9 / 10),
                  ((pba << 10) - hw->max_frame_size));

        hw->fc_high_water = hwm & 0xFFF8;       /* 8-byte granularity */
        hw->fc_low_water = hw->fc_high_water - 8;
        hw->fc_pause_time = E1000_FC_PAUSE_TIME;
        hw->fc_send_xon = 1;
        hw->fc = hw->original_fc;

        /* Allow time for pending master requests to run */
        e1000_reset_hw(hw);
        if (hw->mac_type >= e1000_82544)
                ew32(WUC, 0);

        if (e1000_init_hw(hw))
                DPRINTK(PROBE, ERR, "Hardware Error\n");
        e1000_update_mng_vlan(adapter);

        /* if (adapter->hwflags & HWFLAGS_PHY_PWR_BIT) { */
        if (hw->mac_type >= e1000_82544 &&
            hw->autoneg == 1 &&
            hw->autoneg_advertised == ADVERTISE_1000_FULL) {
                u32 ctrl = er32(CTRL);
                /* clear phy power management bit if we are in gig only mode,
                 * which if enabled will attempt negotiation to 100Mb, which
                 * can cause a loss of link at power off or driver unload */
                ctrl &= ~E1000_CTRL_SWDPIN3;
                ew32(CTRL, ctrl);
        }

        /* Enable h/w to recognize an 802.1Q VLAN Ethernet packet */
        ew32(VET, ETHERNET_IEEE_VLAN_TYPE);

        e1000_reset_adaptive(hw);
        e1000_phy_get_info(hw, &adapter->phy_info);

        e1000_release_manageability(adapter);
}

/**
 *  Dump the eeprom for users having checksum issues
 **/
static void e1000_dump_eeprom(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct ethtool_eeprom eeprom;
        const struct ethtool_ops *ops = netdev->ethtool_ops;
        u8 *data;
        int i;
        u16 csum_old, csum_new = 0;

        eeprom.len = ops->get_eeprom_len(netdev);
        eeprom.offset = 0;

        data = kmalloc(eeprom.len, GFP_KERNEL);
        if (!data) {
                printk(KERN_ERR "Unable to allocate memory to dump EEPROM"
                       " data\n");
                return;
        }

        ops->get_eeprom(netdev, &eeprom, data);

        csum_old = (data[EEPROM_CHECKSUM_REG * 2]) +
                   (data[EEPROM_CHECKSUM_REG * 2 + 1] << 8);
        for (i = 0; i < EEPROM_CHECKSUM_REG * 2; i += 2)
                csum_new += data[i] + (data[i + 1] << 8);
        csum_new = EEPROM_SUM - csum_new;

        printk(KERN_ERR "/*********************/\n");
        printk(KERN_ERR "Current EEPROM Checksum : 0x%04x\n", csum_old);
        printk(KERN_ERR "Calculated              : 0x%04x\n", csum_new);

        printk(KERN_ERR "Offset    Values\n");
        printk(KERN_ERR "========  ======\n");
        print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, data, 128, 0);

        printk(KERN_ERR "Include this output when contacting your support "
               "provider.\n");
        printk(KERN_ERR "This is not a software error! Something bad "
               "happened to your hardware or\n");
        printk(KERN_ERR "EEPROM image. Ignoring this "
               "problem could result in further problems,\n");
        printk(KERN_ERR "possibly loss of data, corruption or system hangs!\n");
        printk(KERN_ERR "The MAC Address will be reset to 00:00:00:00:00:00, "
               "which is invalid\n");
        printk(KERN_ERR "and requires you to set the proper MAC "
               "address manually before continuing\n");
        printk(KERN_ERR "to enable this network device.\n");
        printk(KERN_ERR "Please inspect the EEPROM dump and report the issue "
               "to your hardware vendor\n");
        printk(KERN_ERR "or Intel Customer Support.\n");
        printk(KERN_ERR "/*********************/\n");

        kfree(data);
}

/**
 * e1000_is_need_ioport - determine if an adapter needs ioport resources or not
 * @pdev: PCI device information struct
 *
 * Return true if an adapter needs ioport resources
 **/
static int e1000_is_need_ioport(struct pci_dev *pdev)
{
        switch (pdev->device) {
        case E1000_DEV_ID_82540EM:
        case E1000_DEV_ID_82540EM_LOM:
        case E1000_DEV_ID_82540EP:
        case E1000_DEV_ID_82540EP_LOM:
        case E1000_DEV_ID_82540EP_LP:
        case E1000_DEV_ID_82541EI:
        case E1000_DEV_ID_82541EI_MOBILE:
        case E1000_DEV_ID_82541ER:
        case E1000_DEV_ID_82541ER_LOM:
        case E1000_DEV_ID_82541GI:
        case E1000_DEV_ID_82541GI_LF:
        case E1000_DEV_ID_82541GI_MOBILE:
        case E1000_DEV_ID_82544EI_COPPER:
        case E1000_DEV_ID_82544EI_FIBER:
        case E1000_DEV_ID_82544GC_COPPER:
        case E1000_DEV_ID_82544GC_LOM:
        case E1000_DEV_ID_82545EM_COPPER:
        case E1000_DEV_ID_82545EM_FIBER:
        case E1000_DEV_ID_82546EB_COPPER:
        case E1000_DEV_ID_82546EB_FIBER:
        case E1000_DEV_ID_82546EB_QUAD_COPPER:
                return true;
        default:
                return false;
        }
}

static const struct net_device_ops e1000_netdev_ops = {
        .ndo_open               = e1000_open,
        .ndo_stop               = e1000_close,
        .ndo_start_xmit         = e1000_xmit_frame,
        .ndo_get_stats          = e1000_get_stats,
        .ndo_set_rx_mode        = e1000_set_rx_mode,
        .ndo_set_mac_address    = e1000_set_mac,
        .ndo_tx_timeout         = e1000_tx_timeout,
        .ndo_change_mtu         = e1000_change_mtu,
        .ndo_do_ioctl           = e1000_ioctl,
        .ndo_validate_addr      = eth_validate_addr,

        .ndo_vlan_rx_register   = e1000_vlan_rx_register,
        .ndo_vlan_rx_add_vid    = e1000_vlan_rx_add_vid,
        .ndo_vlan_rx_kill_vid   = e1000_vlan_rx_kill_vid,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = e1000_netpoll,
#endif
};

/**
 * e1000_probe - Device Initialization Routine
 * @pdev: PCI device information struct
 * @ent: entry in e1000_pci_tbl
 *
 * Returns 0 on success, negative on failure
 *
 * e1000_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 e1000_probe(struct pci_dev *pdev,
                                 const struct pci_device_id *ent)
{
        struct net_device *netdev;
        struct e1000_adapter *adapter;
        struct e1000_hw *hw;

        static int cards_found = 0;
        static int global_quad_port_a = 0; /* global ksp3 port a indication */
        int i, err, pci_using_dac;
        u16 eeprom_data = 0;
        u16 eeprom_apme_mask = E1000_EEPROM_APME;
        int bars, need_ioport;

        /* do not allocate ioport bars when not needed */
        need_ioport = e1000_is_need_ioport(pdev);
        if (need_ioport) {
                bars = pci_select_bars(pdev, IORESOURCE_MEM | IORESOURCE_IO);
                err = pci_enable_device(pdev);
        } else {
                bars = pci_select_bars(pdev, IORESOURCE_MEM);
                err = pci_enable_device_mem(pdev);
        }
        if (err)
                return err;

        if (!pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) &&
            !pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64))) {
                pci_using_dac = 1;
        } else {
                err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
                if (err) {
                        err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
                        if (err) {
                                E1000_ERR("No usable DMA configuration, "
                                          "aborting\n");
                                goto err_dma;
                        }
                }
                pci_using_dac = 0;
        }

        err = pci_request_selected_regions(pdev, bars, e1000_driver_name);
        if (err)
                goto err_pci_reg;

        pci_set_master(pdev);

        err = -ENOMEM;
        netdev = alloc_etherdev(sizeof(struct e1000_adapter));
        if (!netdev)
                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;
        adapter->msg_enable = (1 << debug) - 1;
        adapter->bars = bars;
        adapter->need_ioport = need_ioport;

        hw = &adapter->hw;
        hw->back = adapter;

        err = -EIO;
        hw->hw_addr = pci_ioremap_bar(pdev, BAR_0);
        if (!hw->hw_addr)
                goto err_ioremap;

        if (adapter->need_ioport) {
                for (i = BAR_1; i <= BAR_5; i++) {
                        if (pci_resource_len(pdev, i) == 0)
                                continue;
                        if (pci_resource_flags(pdev, i) & IORESOURCE_IO) {
                                hw->io_base = pci_resource_start(pdev, i);
                                break;
                        }
                }
        }

        netdev->netdev_ops = &e1000_netdev_ops;
        e1000_set_ethtool_ops(netdev);
        netdev->watchdog_timeo = 5 * HZ;
        netif_napi_add(netdev, &adapter->napi, e1000_clean, 64);

        strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);

        adapter->bd_number = cards_found;

        /* setup the private structure */

        err = e1000_sw_init(adapter);
        if (err)
                goto err_sw_init;

        err = -EIO;

        if (hw->mac_type >= e1000_82543) {
                netdev->features = NETIF_F_SG |
                                   NETIF_F_HW_CSUM |
                                   NETIF_F_HW_VLAN_TX |
                                   NETIF_F_HW_VLAN_RX |
                                   NETIF_F_HW_VLAN_FILTER;
        }

        if ((hw->mac_type >= e1000_82544) &&
           (hw->mac_type != e1000_82547))
                netdev->features |= NETIF_F_TSO;

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

        netdev->vlan_features |= NETIF_F_TSO;
        netdev->vlan_features |= NETIF_F_HW_CSUM;
        netdev->vlan_features |= NETIF_F_SG;

        adapter->en_mng_pt = e1000_enable_mng_pass_thru(hw);

        /* initialize eeprom parameters */
        if (e1000_init_eeprom_params(hw)) {
                E1000_ERR("EEPROM initialization failed\n");
                goto err_eeprom;
        }

        /* before reading the EEPROM, reset the controller to
         * put the device in a known good starting state */

        e1000_reset_hw(hw);

        /* make sure the EEPROM is good */
        if (e1000_validate_eeprom_checksum(hw) < 0) {
                DPRINTK(PROBE, ERR, "The EEPROM Checksum Is Not Valid\n");
                e1000_dump_eeprom(adapter);
                /*
                 * set MAC address to all zeroes to invalidate and temporary
                 * disable this device for the user. This blocks regular
                 * traffic while still permitting ethtool ioctls from reaching
                 * the hardware as well as allowing the user to run the
                 * interface after manually setting a hw addr using
                 * `ip set address`
                 */
                memset(hw->mac_addr, 0, netdev->addr_len);
        } else {
                /* copy the MAC address out of the EEPROM */
                if (e1000_read_mac_addr(hw))
                        DPRINTK(PROBE, ERR, "EEPROM Read Error\n");
        }
        /* don't block initalization here due to bad MAC address */
        memcpy(netdev->dev_addr, hw->mac_addr, netdev->addr_len);
        memcpy(netdev->perm_addr, hw->mac_addr, netdev->addr_len);

        if (!is_valid_ether_addr(netdev->perm_addr))
                DPRINTK(PROBE, ERR, "Invalid MAC Address\n");

        e1000_get_bus_info(hw);

        init_timer(&adapter->tx_fifo_stall_timer);
        adapter->tx_fifo_stall_timer.function = &e1000_82547_tx_fifo_stall;
        adapter->tx_fifo_stall_timer.data = (unsigned long)adapter;

        init_timer(&adapter->watchdog_timer);
        adapter->watchdog_timer.function = &e1000_watchdog;
        adapter->watchdog_timer.data = (unsigned long) adapter;

        init_timer(&adapter->phy_info_timer);
        adapter->phy_info_timer.function = &e1000_update_phy_info;
        adapter->phy_info_timer.data = (unsigned long)adapter;

        INIT_WORK(&adapter->reset_task, e1000_reset_task);

        e1000_check_options(adapter);

        /* Initial Wake on LAN setting
         * If APM wake is enabled in the EEPROM,
         * enable the ACPI Magic Packet filter
         */

        switch (hw->mac_type) {
        case e1000_82542_rev2_0:
        case e1000_82542_rev2_1:
        case e1000_82543:
                break;
        case e1000_82544:
                e1000_read_eeprom(hw,
                        EEPROM_INIT_CONTROL2_REG, 1, &eeprom_data);
                eeprom_apme_mask = E1000_EEPROM_82544_APM;
                break;
        case e1000_82546:
        case e1000_82546_rev_3:
                if (er32(STATUS) & E1000_STATUS_FUNC_1){
                        e1000_read_eeprom(hw,
                                EEPROM_INIT_CONTROL3_PORT_B, 1, &eeprom_data);
                        break;
                }
                /* Fall Through */
        default:
                e1000_read_eeprom(hw,
                        EEPROM_INIT_CONTROL3_PORT_A, 1, &eeprom_data);
                break;
        }
        if (eeprom_data & eeprom_apme_mask)
                adapter->eeprom_wol |= E1000_WUFC_MAG;

        /* now that we have the eeprom settings, apply the special cases
         * where the eeprom may be wrong or the board simply won't support
         * wake on lan on a particular port */
        switch (pdev->device) {
        case E1000_DEV_ID_82546GB_PCIE:
                adapter->eeprom_wol = 0;
                break;
        case E1000_DEV_ID_82546EB_FIBER:
        case E1000_DEV_ID_82546GB_FIBER:
                /* Wake events only supported on port A for dual fiber
                 * regardless of eeprom setting */
                if (er32(STATUS) & E1000_STATUS_FUNC_1)
                        adapter->eeprom_wol = 0;
                break;
        case E1000_DEV_ID_82546GB_QUAD_COPPER_KSP3:
                /* if quad port adapter, disable WoL on all but port A */
                if (global_quad_port_a != 0)
                        adapter->eeprom_wol = 0;
                else
                        adapter->quad_port_a = 1;
                /* Reset for multiple quad port adapters */
                if (++global_quad_port_a == 4)
                        global_quad_port_a = 0;
                break;
        }

        /* initialize the wol settings based on the eeprom settings */
        adapter->wol = adapter->eeprom_wol;
        device_set_wakeup_enable(&adapter->pdev->dev, adapter->wol);

        /* print bus type/speed/width info */
        DPRINTK(PROBE, INFO, "(PCI%s:%s:%s) ",
                ((hw->bus_type == e1000_bus_type_pcix) ? "-X" : ""),
                ((hw->bus_speed == e1000_bus_speed_133) ? "133MHz" :
                 (hw->bus_speed == e1000_bus_speed_120) ? "120MHz" :
                 (hw->bus_speed == e1000_bus_speed_100) ? "100MHz" :
                 (hw->bus_speed == e1000_bus_speed_66) ? "66MHz" : "33MHz"),
                ((hw->bus_width == e1000_bus_width_64) ? "64-bit" : "32-bit"));

        printk("%pM\n", netdev->dev_addr);

        /* reset the hardware with the new settings */
        e1000_reset(adapter);

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

        /* carrier off reporting is important to ethtool even BEFORE open */
        netif_carrier_off(netdev);

        DPRINTK(PROBE, INFO, "Intel(R) PRO/1000 Network Connection\n");

        cards_found++;
        return 0;

err_register:
err_eeprom:
        e1000_phy_hw_reset(hw);

        if (hw->flash_address)
                iounmap(hw->flash_address);
        kfree(adapter->tx_ring);
        kfree(adapter->rx_ring);
err_sw_init:
        iounmap(hw->hw_addr);
err_ioremap:
        free_netdev(netdev);
err_alloc_etherdev:
        pci_release_selected_regions(pdev, bars);
err_pci_reg:
err_dma:
        pci_disable_device(pdev);
        return err;
}

/**
 * e1000_remove - Device Removal Routine
 * @pdev: PCI device information struct
 *
 * e1000_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 e1000_remove(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;

        cancel_work_sync(&adapter->reset_task);

        e1000_release_manageability(adapter);

        unregister_netdev(netdev);

        e1000_phy_hw_reset(hw);

        kfree(adapter->tx_ring);
        kfree(adapter->rx_ring);

        iounmap(hw->hw_addr);
        if (hw->flash_address)
                iounmap(hw->flash_address);
        pci_release_selected_regions(pdev, adapter->bars);

        free_netdev(netdev);

        pci_disable_device(pdev);
}

/**
 * e1000_sw_init - Initialize general software structures (struct e1000_adapter)
 * @adapter: board private structure to initialize
 *
 * e1000_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 e1000_sw_init(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;

        /* PCI config space info */

        hw->vendor_id = pdev->vendor;
        hw->device_id = pdev->device;
        hw->subsystem_vendor_id = pdev->subsystem_vendor;
        hw->subsystem_id = pdev->subsystem_device;
        hw->revision_id = pdev->revision;

        pci_read_config_word(pdev, PCI_COMMAND, &hw->pci_cmd_word);

        adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
        hw->max_frame_size = netdev->mtu +
                             ENET_HEADER_SIZE + ETHERNET_FCS_SIZE;
        hw->min_frame_size = MINIMUM_ETHERNET_FRAME_SIZE;

        /* identify the MAC */

        if (e1000_set_mac_type(hw)) {
                DPRINTK(PROBE, ERR, "Unknown MAC Type\n");
                return -EIO;
        }

        switch (hw->mac_type) {
        default:
                break;
        case e1000_82541:
        case e1000_82547:
        case e1000_82541_rev_2:
        case e1000_82547_rev_2:
                hw->phy_init_script = 1;
                break;
        }

        e1000_set_media_type(hw);

        hw->wait_autoneg_complete = false;
        hw->tbi_compatibility_en = true;
        hw->adaptive_ifs = true;

        /* Copper options */

        if (hw->media_type == e1000_media_type_copper) {
                hw->mdix = AUTO_ALL_MODES;
                hw->disable_polarity_correction = false;
                hw->master_slave = E1000_MASTER_SLAVE;
        }

        adapter->num_tx_queues = 1;
        adapter->num_rx_queues = 1;

        if (e1000_alloc_queues(adapter)) {
                DPRINTK(PROBE, ERR, "Unable to allocate memory for queues\n");
                return -ENOMEM;
        }

        /* Explicitly disable IRQ since the NIC can be in any state. */
        e1000_irq_disable(adapter);

        spin_lock_init(&adapter->stats_lock);

        set_bit(__E1000_DOWN, &adapter->flags);

        return 0;
}

/**
 * e1000_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.
 **/

static int __devinit e1000_alloc_queues(struct e1000_adapter *adapter)
{
        adapter->tx_ring = kcalloc(adapter->num_tx_queues,
                                   sizeof(struct e1000_tx_ring), GFP_KERNEL);
        if (!adapter->tx_ring)
                return -ENOMEM;

        adapter->rx_ring = kcalloc(adapter->num_rx_queues,
                                   sizeof(struct e1000_rx_ring), GFP_KERNEL);
        if (!adapter->rx_ring) {
                kfree(adapter->tx_ring);
                return -ENOMEM;
        }

        return E1000_SUCCESS;
}

/**
 * e1000_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 e1000_open(struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        int err;

        /* disallow open during test */
        if (test_bit(__E1000_TESTING, &adapter->flags))
                return -EBUSY;

        netif_carrier_off(netdev);

        /* allocate transmit descriptors */
        err = e1000_setup_all_tx_resources(adapter);
        if (err)
                goto err_setup_tx;

        /* allocate receive descriptors */
        err = e1000_setup_all_rx_resources(adapter);
        if (err)
                goto err_setup_rx;

        e1000_power_up_phy(adapter);

        adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;
        if ((hw->mng_cookie.status &
                          E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT)) {
                e1000_update_mng_vlan(adapter);
        }

        /* before we allocate an interrupt, we must be ready to handle it.
         * Setting DEBUG_SHIRQ in the kernel makes it fire an interrupt
         * as soon as we call pci_request_irq, so we have to setup our
         * clean_rx handler before we do so.  */
        e1000_configure(adapter);

        err = e1000_request_irq(adapter);
        if (err)
                goto err_req_irq;

        /* From here on the code is the same as e1000_up() */
        clear_bit(__E1000_DOWN, &adapter->flags);

        napi_enable(&adapter->napi);

        e1000_irq_enable(adapter);

        netif_start_queue(netdev);

        /* fire a link status change interrupt to start the watchdog */
        ew32(ICS, E1000_ICS_LSC);

        return E1000_SUCCESS;

err_req_irq:
        e1000_power_down_phy(adapter);
        e1000_free_all_rx_resources(adapter);
err_setup_rx:
        e1000_free_all_tx_resources(adapter);
err_setup_tx:
        e1000_reset(adapter);

        return err;
}

/**
 * e1000_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 e1000_close(struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;

        WARN_ON(test_bit(__E1000_RESETTING, &adapter->flags));
        e1000_down(adapter);
        e1000_power_down_phy(adapter);
        e1000_free_irq(adapter);

        e1000_free_all_tx_resources(adapter);
        e1000_free_all_rx_resources(adapter);

        /* kill manageability vlan ID if supported, but not if a vlan with
         * the same ID is registered on the host OS (let 8021q kill it) */
        if ((hw->mng_cookie.status &
                          E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT) &&
             !(adapter->vlgrp &&
               vlan_group_get_device(adapter->vlgrp, adapter->mng_vlan_id))) {
                e1000_vlan_rx_kill_vid(netdev, adapter->mng_vlan_id);
        }

        return 0;
}

/**
 * e1000_check_64k_bound - check that memory doesn't cross 64kB boundary
 * @adapter: address of board private structure
 * @start: address of beginning of memory
 * @len: length of memory
 **/
static bool e1000_check_64k_bound(struct e1000_adapter *adapter, void *start,
                                  unsigned long len)
{
        struct e1000_hw *hw = &adapter->hw;
        unsigned long begin = (unsigned long)start;
        unsigned long end = begin + len;

        /* First rev 82545 and 82546 need to not allow any memory
         * write location to cross 64k boundary due to errata 23 */
        if (hw->mac_type == e1000_82545 ||
            hw->mac_type == e1000_82546) {
                return ((begin ^ (end - 1)) >> 16) != 0 ? false : true;
        }

        return true;
}

/**
 * e1000_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
 **/

static int e1000_setup_tx_resources(struct e1000_adapter *adapter,
                                    struct e1000_tx_ring *txdr)
{
        struct pci_dev *pdev = adapter->pdev;
        int size;

        size = sizeof(struct e1000_buffer) * txdr->count;
        txdr->buffer_info = vmalloc(size);
        if (!txdr->buffer_info) {
                DPRINTK(PROBE, ERR,
                "Unable to allocate memory for the transmit descriptor ring\n");
                return -ENOMEM;
        }
        memset(txdr->buffer_info, 0, size);

        /* round up to nearest 4K */

        txdr->size = txdr->count * sizeof(struct e1000_tx_desc);
        txdr->size = ALIGN(txdr->size, 4096);

        txdr->desc = pci_alloc_consistent(pdev, txdr->size, &txdr->dma);
        if (!txdr->desc) {
setup_tx_desc_die:
                vfree(txdr->buffer_info);
                DPRINTK(PROBE, ERR,
                "Unable to allocate memory for the transmit descriptor ring\n");
                return -ENOMEM;
        }

        /* Fix for errata 23, can't cross 64kB boundary */
        if (!e1000_check_64k_bound(adapter, txdr->desc, txdr->size)) {
                void *olddesc = txdr->desc;
                dma_addr_t olddma = txdr->dma;
                DPRINTK(TX_ERR, ERR, "txdr align check failed: %u bytes "
                                     "at %p\n", txdr->size, txdr->desc);
                /* Try again, without freeing the previous */
                txdr->desc = pci_alloc_consistent(pdev, txdr->size, &txdr->dma);
                /* Failed allocation, critical failure */
                if (!txdr->desc) {
                        pci_free_consistent(pdev, txdr->size, olddesc, olddma);
                        goto setup_tx_desc_die;
                }

                if (!e1000_check_64k_bound(adapter, txdr->desc, txdr->size)) {
                        /* give up */
                        pci_free_consistent(pdev, txdr->size, txdr->desc,
                                            txdr->dma);
                        pci_free_consistent(pdev, txdr->size, olddesc, olddma);
                        DPRINTK(PROBE, ERR,
                                "Unable to allocate aligned memory "
                                "for the transmit descriptor ring\n");
                        vfree(txdr->buffer_info);
                        return -ENOMEM;
                } else {
                        /* Free old allocation, new allocation was successful */
                        pci_free_consistent(pdev, txdr->size, olddesc, olddma);
                }
        }
        memset(txdr->desc, 0, txdr->size);

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

        return 0;
}

/**
 * e1000_setup_all_tx_resources - wrapper to allocate Tx resources
 *                                (Descriptors) for all queues
 * @adapter: board private structure
 *
 * Return 0 on success, negative on failure
 **/

int e1000_setup_all_tx_resources(struct e1000_adapter *adapter)
{
        int i, err = 0;

        for (i = 0; i < adapter->num_tx_queues; i++) {
                err = e1000_setup_tx_resources(adapter, &adapter->tx_ring[i]);
                if (err) {
                        DPRINTK(PROBE, ERR,
                                "Allocation for Tx Queue %u failed\n", i);
                        for (i-- ; i >= 0; i--)
                                e1000_free_tx_resources(adapter,
                                                        &adapter->tx_ring[i]);
                        break;
                }
        }

        return err;
}

/**
 * e1000_configure_tx - Configure 8254x Transmit Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Tx unit of the MAC after a reset.
 **/

static void e1000_configure_tx(struct e1000_adapter *adapter)
{
        u64 tdba;
        struct e1000_hw *hw = &adapter->hw;
        u32 tdlen, tctl, tipg;
        u32 ipgr1, ipgr2;

        /* Setup the HW Tx Head and Tail descriptor pointers */

        switch (adapter->num_tx_queues) {
        case 1:
        default:
                tdba = adapter->tx_ring[0].dma;
                tdlen = adapter->tx_ring[0].count *
                        sizeof(struct e1000_tx_desc);
                ew32(TDLEN, tdlen);
                ew32(TDBAH, (tdba >> 32));
                ew32(TDBAL, (tdba & 0x00000000ffffffffULL));
                ew32(TDT, 0);
                ew32(TDH, 0);
                adapter->tx_ring[0].tdh = ((hw->mac_type >= e1000_82543) ? E1000_TDH : E1000_82542_TDH);
                adapter->tx_ring[0].tdt = ((hw->mac_type >= e1000_82543) ? E1000_TDT : E1000_82542_TDT);
                break;
        }

        /* Set the default values for the Tx Inter Packet Gap timer */
        if ((hw->media_type == e1000_media_type_fiber ||
             hw->media_type == e1000_media_type_internal_serdes))
                tipg = DEFAULT_82543_TIPG_IPGT_FIBER;
        else
                tipg = DEFAULT_82543_TIPG_IPGT_COPPER;

        switch (hw->mac_type) {
        case e1000_82542_rev2_0:
        case e1000_82542_rev2_1:
                tipg = DEFAULT_82542_TIPG_IPGT;
                ipgr1 = DEFAULT_82542_TIPG_IPGR1;
                ipgr2 = DEFAULT_82542_TIPG_IPGR2;
                break;
        default:
                ipgr1 = DEFAULT_82543_TIPG_IPGR1;
                ipgr2 = DEFAULT_82543_TIPG_IPGR2;
                break;
        }
        tipg |= ipgr1 << E1000_TIPG_IPGR1_SHIFT;
        tipg |= ipgr2 << E1000_TIPG_IPGR2_SHIFT;
        ew32(TIPG, tipg);

        /* Set the Tx Interrupt Delay register */

        ew32(TIDV, adapter->tx_int_delay);
        if (hw->mac_type >= e1000_82540)
                ew32(TADV, adapter->tx_abs_int_delay);

        /* Program the Transmit Control Register */

        tctl = er32(TCTL);
        tctl &= ~E1000_TCTL_CT;
        tctl |= E1000_TCTL_PSP | E1000_TCTL_RTLC |
                (E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT);

        e1000_config_collision_dist(hw);

        /* Setup Transmit Descriptor Settings for eop descriptor */
        adapter->txd_cmd = E1000_TXD_CMD_EOP | E1000_TXD_CMD_IFCS;

        /* only set IDE if we are delaying interrupts using the timers */
        if (adapter->tx_int_delay)
                adapter->txd_cmd |= E1000_TXD_CMD_IDE;

        if (hw->mac_type < e1000_82543)
                adapter->txd_cmd |= E1000_TXD_CMD_RPS;
        else
                adapter->txd_cmd |= E1000_TXD_CMD_RS;

        /* Cache if we're 82544 running in PCI-X because we'll
         * need this to apply a workaround later in the send path. */
        if (hw->mac_type == e1000_82544 &&
            hw->bus_type == e1000_bus_type_pcix)
                adapter->pcix_82544 = 1;

        ew32(TCTL, tctl);

}

/**
 * e1000_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
 **/

static int e1000_setup_rx_resources(struct e1000_adapter *adapter,
                                    struct e1000_rx_ring *rxdr)
{
        struct pci_dev *pdev = adapter->pdev;
        int size, desc_len;

        size = sizeof(struct e1000_buffer) * rxdr->count;
        rxdr->buffer_info = vmalloc(size);
        if (!rxdr->buffer_info) {
                DPRINTK(PROBE, ERR,
                "Unable to allocate memory for the receive descriptor ring\n");
                return -ENOMEM;
        }
        memset(rxdr->buffer_info, 0, size);

        desc_len = sizeof(struct e1000_rx_desc);

        /* Round up to nearest 4K */

        rxdr->size = rxdr->count * desc_len;
        rxdr->size = ALIGN(rxdr->size, 4096);

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

        if (!rxdr->desc) {
                DPRINTK(PROBE, ERR,
                "Unable to allocate memory for the receive descriptor ring\n");
setup_rx_desc_die:
                vfree(rxdr->buffer_info);
                return -ENOMEM;
        }

        /* Fix for errata 23, can't cross 64kB boundary */
        if (!e1000_check_64k_bound(adapter, rxdr->desc, rxdr->size)) {
                void *olddesc = rxdr->desc;
                dma_addr_t olddma = rxdr->dma;
                DPRINTK(RX_ERR, ERR, "rxdr align check failed: %u bytes "
                                     "at %p\n", rxdr->size, rxdr->desc);
                /* Try again, without freeing the previous */
                rxdr->desc = pci_alloc_consistent(pdev, rxdr->size, &rxdr->dma);
                /* Failed allocation, critical failure */
                if (!rxdr->desc) {
                        pci_free_consistent(pdev, rxdr->size, olddesc, olddma);
                        DPRINTK(PROBE, ERR,
                                "Unable to allocate memory "
                                "for the receive descriptor ring\n");
                        goto setup_rx_desc_die;
                }

                if (!e1000_check_64k_bound(adapter, rxdr->desc, rxdr->size)) {
                        /* give up */
                        pci_free_consistent(pdev, rxdr->size, rxdr->desc,
                                            rxdr->dma);
                        pci_free_consistent(pdev, rxdr->size, olddesc, olddma);
                        DPRINTK(PROBE, ERR,
                                "Unable to allocate aligned memory "
                                "for the receive descriptor ring\n");
                        goto setup_rx_desc_die;
                } else {
                        /* Free old allocation, new allocation was successful */
                        pci_free_consistent(pdev, rxdr->size, olddesc, olddma);
                }
        }
        memset(rxdr->desc, 0, rxdr->size);

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

        return 0;
}

/**
 * e1000_setup_all_rx_resources - wrapper to allocate Rx resources
 *                                (Descriptors) for all queues
 * @adapter: board private structure
 *
 * Return 0 on success, negative on failure
 **/

int e1000_setup_all_rx_resources(struct e1000_adapter *adapter)
{
        int i, err = 0;

        for (i = 0; i < adapter->num_rx_queues; i++) {
                err = e1000_setup_rx_resources(adapter, &adapter->rx_ring[i]);
                if (err) {
                        DPRINTK(PROBE, ERR,
                                "Allocation for Rx Queue %u failed\n", i);
                        for (i-- ; i >= 0; i--)
                                e1000_free_rx_resources(adapter,
                                                        &adapter->rx_ring[i]);
                        break;
                }
        }

        return err;
}

/**
 * e1000_setup_rctl - configure the receive control registers
 * @adapter: Board private structure
 **/
static void e1000_setup_rctl(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 rctl;

        rctl = er32(RCTL);

        rctl &= ~(3 << E1000_RCTL_MO_SHIFT);

        rctl |= E1000_RCTL_EN | E1000_RCTL_BAM |
                E1000_RCTL_LBM_NO | E1000_RCTL_RDMTS_HALF |
                (hw->mc_filter_type << E1000_RCTL_MO_SHIFT);

        if (hw->tbi_compatibility_on == 1)
                rctl |= E1000_RCTL_SBP;
        else
                rctl &= ~E1000_RCTL_SBP;

        if (adapter->netdev->mtu <= ETH_DATA_LEN)
                rctl &= ~E1000_RCTL_LPE;
        else
                rctl |= E1000_RCTL_LPE;

        /* Setup buffer sizes */
        rctl &= ~E1000_RCTL_SZ_4096;
        rctl |= E1000_RCTL_BSEX;
        switch (adapter->rx_buffer_len) {
                case E1000_RXBUFFER_256:
                        rctl |= E1000_RCTL_SZ_256;
                        rctl &= ~E1000_RCTL_BSEX;
                        break;
                case E1000_RXBUFFER_512:
                        rctl |= E1000_RCTL_SZ_512;
                        rctl &= ~E1000_RCTL_BSEX;
                        break;
                case E1000_RXBUFFER_1024:
                        rctl |= E1000_RCTL_SZ_1024;
                        rctl &= ~E1000_RCTL_BSEX;
                        break;
                case E1000_RXBUFFER_2048:
                default:
                        rctl |= E1000_RCTL_SZ_2048;
                        rctl &= ~E1000_RCTL_BSEX;
                        break;
                case E1000_RXBUFFER_4096:
                        rctl |= E1000_RCTL_SZ_4096;
                        break;
                case E1000_RXBUFFER_8192:
                        rctl |= E1000_RCTL_SZ_8192;
                        break;
                case E1000_RXBUFFER_16384:
                        rctl |= E1000_RCTL_SZ_16384;
                        break;
        }

        ew32(RCTL, rctl);
}

/**
 * e1000_configure_rx - Configure 8254x Receive Unit after Reset
 * @adapter: board private structure
 *
 * Configure the Rx unit of the MAC after a reset.
 **/

static void e1000_configure_rx(struct e1000_adapter *adapter)
{
        u64 rdba;
        struct e1000_hw *hw = &adapter->hw;
        u32 rdlen, rctl, rxcsum;

        if (adapter->netdev->mtu > ETH_DATA_LEN) {
                rdlen = adapter->rx_ring[0].count *
                        sizeof(struct e1000_rx_desc);
                adapter->clean_rx = e1000_clean_jumbo_rx_irq;
                adapter->alloc_rx_buf = e1000_alloc_jumbo_rx_buffers;
        } else {
                rdlen = adapter->rx_ring[0].count *
                        sizeof(struct e1000_rx_desc);
                adapter->clean_rx = e1000_clean_rx_irq;
                adapter->alloc_rx_buf = e1000_alloc_rx_buffers;
        }

        /* disable receives while setting up the descriptors */
        rctl = er32(RCTL);
        ew32(RCTL, rctl & ~E1000_RCTL_EN);

        /* set the Receive Delay Timer Register */
        ew32(RDTR, adapter->rx_int_delay);

        if (hw->mac_type >= e1000_82540) {
                ew32(RADV, adapter->rx_abs_int_delay);
                if (adapter->itr_setting != 0)
                        ew32(ITR, 1000000000 / (adapter->itr * 256));
        }

        /* Setup the HW Rx Head and Tail Descriptor Pointers and
         * the Base and Length of the Rx Descriptor Ring */
        switch (adapter->num_rx_queues) {
        case 1:
        default:
                rdba = adapter->rx_ring[0].dma;
                ew32(RDLEN, rdlen);
                ew32(RDBAH, (rdba >> 32));
                ew32(RDBAL, (rdba & 0x00000000ffffffffULL));
                ew32(RDT, 0);
                ew32(RDH, 0);
                adapter->rx_ring[0].rdh = ((hw->mac_type >= e1000_82543) ? E1000_RDH : E1000_82542_RDH);
                adapter->rx_ring[0].rdt = ((hw->mac_type >= e1000_82543) ? E1000_RDT : E1000_82542_RDT);
                break;
        }

        /* Enable 82543 Receive Checksum Offload for TCP and UDP */
        if (hw->mac_type >= e1000_82543) {
                rxcsum = er32(RXCSUM);
                if (adapter->rx_csum)
                        rxcsum |= E1000_RXCSUM_TUOFL;
                else
                        /* don't need to clear IPPCSE as it defaults to 0 */
                        rxcsum &= ~E1000_RXCSUM_TUOFL;
                ew32(RXCSUM, rxcsum);
        }

        /* Enable Receives */
        ew32(RCTL, rctl);
}

/**
 * e1000_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 e1000_free_tx_resources(struct e1000_adapter *adapter,
                                    struct e1000_tx_ring *tx_ring)
{
        struct pci_dev *pdev = adapter->pdev;

        e1000_clean_tx_ring(adapter, tx_ring);

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

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

        tx_ring->desc = NULL;
}

/**
 * e1000_free_all_tx_resources - Free Tx Resources for All Queues
 * @adapter: board private structure
 *
 * Free all transmit software resources
 **/

void e1000_free_all_tx_resources(struct e1000_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                e1000_free_tx_resources(adapter, &adapter->tx_ring[i]);
}

static void e1000_unmap_and_free_tx_resource(struct e1000_adapter *adapter,
                                             struct e1000_buffer *buffer_info)
{
        buffer_info->dma = 0;
        if (buffer_info->skb) {
                skb_dma_unmap(&adapter->pdev->dev, buffer_info->skb,
                              DMA_TO_DEVICE);
                dev_kfree_skb_any(buffer_info->skb);
                buffer_info->skb = NULL;
        }
        buffer_info->time_stamp = 0;
        /* buffer_info must be completely set up in the transmit path */
}

/**
 * e1000_clean_tx_ring - Free Tx Buffers
 * @adapter: board private structure
 * @tx_ring: ring to be cleaned
 **/

static void e1000_clean_tx_ring(struct e1000_adapter *adapter,
                                struct e1000_tx_ring *tx_ring)
{
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_buffer *buffer_info;
        unsigned long size;
        unsigned int i;

        /* Free all the Tx ring sk_buffs */

        for (i = 0; i < tx_ring->count; i++) {
                buffer_info = &tx_ring->buffer_info[i];
                e1000_unmap_and_free_tx_resource(adapter, buffer_info);
        }

        size = sizeof(struct e1000_buffer) * tx_ring->count;
        memset(tx_ring->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;
        tx_ring->last_tx_tso = 0;

        writel(0, hw->hw_addr + tx_ring->tdh);
        writel(0, hw->hw_addr + tx_ring->tdt);
}

/**
 * e1000_clean_all_tx_rings - Free Tx Buffers for all queues
 * @adapter: board private structure
 **/

static void e1000_clean_all_tx_rings(struct e1000_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_tx_queues; i++)
                e1000_clean_tx_ring(adapter, &adapter->tx_ring[i]);
}

/**
 * e1000_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 e1000_free_rx_resources(struct e1000_adapter *adapter,
                                    struct e1000_rx_ring *rx_ring)
{
        struct pci_dev *pdev = adapter->pdev;

        e1000_clean_rx_ring(adapter, rx_ring);

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

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

        rx_ring->desc = NULL;
}

/**
 * e1000_free_all_rx_resources - Free Rx Resources for All Queues
 * @adapter: board private structure
 *
 * Free all receive software resources
 **/

void e1000_free_all_rx_resources(struct e1000_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_rx_queues; i++)
                e1000_free_rx_resources(adapter, &adapter->rx_ring[i]);
}

/**
 * e1000_clean_rx_ring - Free Rx Buffers per Queue
 * @adapter: board private structure
 * @rx_ring: ring to free buffers from
 **/

static void e1000_clean_rx_ring(struct e1000_adapter *adapter,
                                struct e1000_rx_ring *rx_ring)
{
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_buffer *buffer_info;
        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++) {
                buffer_info = &rx_ring->buffer_info[i];
                if (buffer_info->dma &&
                    adapter->clean_rx == e1000_clean_rx_irq) {
                        pci_unmap_single(pdev, buffer_info->dma,
                                         buffer_info->length,
                                         PCI_DMA_FROMDEVICE);
                } else if (buffer_info->dma &&
                           adapter->clean_rx == e1000_clean_jumbo_rx_irq) {
                        pci_unmap_page(pdev, buffer_info->dma,
                                       buffer_info->length,
                                       PCI_DMA_FROMDEVICE);
                }

                buffer_info->dma = 0;
                if (buffer_info->page) {
                        put_page(buffer_info->page);
                        buffer_info->page = NULL;
                }
                if (buffer_info->skb) {
                        dev_kfree_skb(buffer_info->skb);
                        buffer_info->skb = NULL;
                }
        }

        /* there also may be some cached data from a chained receive */
        if (rx_ring->rx_skb_top) {
                dev_kfree_skb(rx_ring->rx_skb_top);
                rx_ring->rx_skb_top = NULL;
        }

        size = sizeof(struct e1000_buffer) * rx_ring->count;
        memset(rx_ring->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, hw->hw_addr + rx_ring->rdh);
        writel(0, hw->hw_addr + rx_ring->rdt);
}

/**
 * e1000_clean_all_rx_rings - Free Rx Buffers for all queues
 * @adapter: board private structure
 **/

static void e1000_clean_all_rx_rings(struct e1000_adapter *adapter)
{
        int i;

        for (i = 0; i < adapter->num_rx_queues; i++)
                e1000_clean_rx_ring(adapter, &adapter->rx_ring[i]);
}

/* The 82542 2.0 (revision 2) needs to have the receive unit in reset
 * and memory write and invalidate disabled for certain operations
 */
static void e1000_enter_82542_rst(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        u32 rctl;

        e1000_pci_clear_mwi(hw);

        rctl = er32(RCTL);
        rctl |= E1000_RCTL_RST;
        ew32(RCTL, rctl);
        E1000_WRITE_FLUSH();
        mdelay(5);

        if (netif_running(netdev))
                e1000_clean_all_rx_rings(adapter);
}

static void e1000_leave_82542_rst(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        u32 rctl;

        rctl = er32(RCTL);
        rctl &= ~E1000_RCTL_RST;
        ew32(RCTL, rctl);
        E1000_WRITE_FLUSH();
        mdelay(5);

        if (hw->pci_cmd_word & PCI_COMMAND_INVALIDATE)
                e1000_pci_set_mwi(hw);

        if (netif_running(netdev)) {
                /* No need to loop, because 82542 supports only 1 queue */
                struct e1000_rx_ring *ring = &adapter->rx_ring[0];
                e1000_configure_rx(adapter);
                adapter->alloc_rx_buf(adapter, ring, E1000_DESC_UNUSED(ring));
        }
}

/**
 * e1000_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 e1000_set_mac(struct net_device *netdev, void *p)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        struct sockaddr *addr = p;

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

        /* 82542 2.0 needs to be in reset to write receive address registers */

        if (hw->mac_type == e1000_82542_rev2_0)
                e1000_enter_82542_rst(adapter);

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

        e1000_rar_set(hw, hw->mac_addr, 0);

        if (hw->mac_type == e1000_82542_rev2_0)
                e1000_leave_82542_rst(adapter);

        return 0;
}

/**
 * e1000_set_rx_mode - Secondary Unicast, Multicast and Promiscuous mode set
 * @netdev: network interface device structure
 *
 * The set_rx_mode entry point is called whenever the unicast or multicast
 * address lists or the network interface flags are updated. This routine is
 * responsible for configuring the hardware for proper unicast, multicast,
 * promiscuous mode, and all-multi behavior.
 **/

static void e1000_set_rx_mode(struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        struct netdev_hw_addr *ha;
        bool use_uc = false;
        struct dev_addr_list *mc_ptr;
        u32 rctl;
        u32 hash_value;
        int i, rar_entries = E1000_RAR_ENTRIES;
        int mta_reg_count = E1000_NUM_MTA_REGISTERS;
        u32 *mcarray = kcalloc(mta_reg_count, sizeof(u32), GFP_ATOMIC);

        if (!mcarray) {
                DPRINTK(PROBE, ERR, "memory allocation failed\n");
                return;
        }

        /* Check for Promiscuous and All Multicast modes */

        rctl = er32(RCTL);

        if (netdev->flags & IFF_PROMISC) {
                rctl |= (E1000_RCTL_UPE | E1000_RCTL_MPE);
                rctl &= ~E1000_RCTL_VFE;
        } else {
                if (netdev->flags & IFF_ALLMULTI)
                        rctl |= E1000_RCTL_MPE;
                else
                        rctl &= ~E1000_RCTL_MPE;
                /* Enable VLAN filter if there is a VLAN */
                if (adapter->vlgrp)
                        rctl |= E1000_RCTL_VFE;
        }

        if (netdev->uc.count > rar_entries - 1) {
                rctl |= E1000_RCTL_UPE;
        } else if (!(netdev->flags & IFF_PROMISC)) {
                rctl &= ~E1000_RCTL_UPE;
                use_uc = true;
        }

        ew32(RCTL, rctl);

        /* 82542 2.0 needs to be in reset to write receive address registers */

        if (hw->mac_type == e1000_82542_rev2_0)
                e1000_enter_82542_rst(adapter);

        /* load the first 14 addresses into the exact filters 1-14. Unicast
         * addresses take precedence to avoid disabling unicast filtering
         * when possible.
         *
         * RAR 0 is used for the station MAC adddress
         * if there are not 14 addresses, go ahead and clear the filters
         */
        i = 1;
        if (use_uc)
                list_for_each_entry(ha, &netdev->uc.list, list) {
                        if (i == rar_entries)
                                break;
                        e1000_rar_set(hw, ha->addr, i++);
                }

        WARN_ON(i == rar_entries);

        mc_ptr = netdev->mc_list;

        for (; i < rar_entries; i++) {
                if (mc_ptr) {
                        e1000_rar_set(hw, mc_ptr->da_addr, i);
                        mc_ptr = mc_ptr->next;
                } else {
                        E1000_WRITE_REG_ARRAY(hw, RA, i << 1, 0);
                        E1000_WRITE_FLUSH();
                        E1000_WRITE_REG_ARRAY(hw, RA, (i << 1) + 1, 0);
                        E1000_WRITE_FLUSH();
                }
        }

        /* load any remaining addresses into the hash table */

        for (; mc_ptr; mc_ptr = mc_ptr->next) {
                u32 hash_reg, hash_bit, mta;
                hash_value = e1000_hash_mc_addr(hw, mc_ptr->da_addr);
                hash_reg = (hash_value >> 5) & 0x7F;
                hash_bit = hash_value & 0x1F;
                mta = (1 << hash_bit);
                mcarray[hash_reg] |= mta;
        }

        /* write the hash table completely, write from bottom to avoid
         * both stupid write combining chipsets, and flushing each write */
        for (i = mta_reg_count - 1; i >= 0 ; i--) {
                /*
                 * If we are on an 82544 has an errata where writing odd
                 * offsets overwrites the previous even offset, but writing
                 * backwards over the range solves the issue by always
                 * writing the odd offset first
                 */
                E1000_WRITE_REG_ARRAY(hw, MTA, i, mcarray[i]);
        }
        E1000_WRITE_FLUSH();

        if (hw->mac_type == e1000_82542_rev2_0)
                e1000_leave_82542_rst(adapter);

        kfree(mcarray);
}

/* Need to wait a few seconds after link up to get diagnostic information from
 * the phy */

static void e1000_update_phy_info(unsigned long data)
{
        struct e1000_adapter *adapter = (struct e1000_adapter *)data;
        struct e1000_hw *hw = &adapter->hw;
        e1000_phy_get_info(hw, &adapter->phy_info);
}

/**
 * e1000_82547_tx_fifo_stall - Timer Call-back
 * @data: pointer to adapter cast into an unsigned long
 **/

static void e1000_82547_tx_fifo_stall(unsigned long data)
{
        struct e1000_adapter *adapter = (struct e1000_adapter *)data;
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        u32 tctl;

        if (atomic_read(&adapter->tx_fifo_stall)) {
                if ((er32(TDT) == er32(TDH)) &&
                   (er32(TDFT) == er32(TDFH)) &&
                   (er32(TDFTS) == er32(TDFHS))) {
                        tctl = er32(TCTL);
                        ew32(TCTL, tctl & ~E1000_TCTL_EN);
                        ew32(TDFT, adapter->tx_head_addr);
                        ew32(TDFH, adapter->tx_head_addr);
                        ew32(TDFTS, adapter->tx_head_addr);
                        ew32(TDFHS, adapter->tx_head_addr);
                        ew32(TCTL, tctl);
                        E1000_WRITE_FLUSH();

                        adapter->tx_fifo_head = 0;
                        atomic_set(&adapter->tx_fifo_stall, 0);
                        netif_wake_queue(netdev);
                } else {
                        mod_timer(&adapter->tx_fifo_stall_timer, jiffies + 1);
                }
        }
}

/**
 * e1000_watchdog - Timer Call-back
 * @data: pointer to adapter cast into an unsigned long
 **/
static void e1000_watchdog(unsigned long data)
{
        struct e1000_adapter *adapter = (struct e1000_adapter *)data;
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct e1000_tx_ring *txdr = adapter->tx_ring;
        u32 link, tctl;

        e1000_check_for_link(hw);

        if ((hw->media_type == e1000_media_type_internal_serdes) &&
           !(er32(TXCW) & E1000_TXCW_ANE))
                link = !hw->serdes_link_down;
        else
                link = er32(STATUS) & E1000_STATUS_LU;

        if (link) {
                if (!netif_carrier_ok(netdev)) {
                        u32 ctrl;
                        bool txb2b = true;
                        e1000_get_speed_and_duplex(hw,
                                                   &adapter->link_speed,
                                                   &adapter->link_duplex);

                        ctrl = er32(CTRL);
                        printk(KERN_INFO "e1000: %s NIC Link is Up %d Mbps %s, "
                               "Flow Control: %s\n",
                               netdev->name,
                               adapter->link_speed,
                               adapter->link_duplex == FULL_DUPLEX ?
                                "Full Duplex" : "Half Duplex",
                                ((ctrl & E1000_CTRL_TFCE) && (ctrl &
                                E1000_CTRL_RFCE)) ? "RX/TX" : ((ctrl &
                                E1000_CTRL_RFCE) ? "RX" : ((ctrl &
                                E1000_CTRL_TFCE) ? "TX" : "None" )));

                        /* tweak tx_queue_len according to speed/duplex
                         * and adjust the timeout factor */
                        netdev->tx_queue_len = adapter->tx_queue_len;
                        adapter->tx_timeout_factor = 1;
                        switch (adapter->link_speed) {
                        case SPEED_10:
                                txb2b = false;
                                netdev->tx_queue_len = 10;
                                adapter->tx_timeout_factor = 8;
                                break;
                        case SPEED_100:
                                txb2b = false;
                                netdev->tx_queue_len = 100;
                                /* maybe add some timeout factor ? */
                                break;
                        }

                        /* enable transmits in the hardware */
                        tctl = er32(TCTL);
                        tctl |= E1000_TCTL_EN;
                        ew32(TCTL, tctl);

                        netif_carrier_on(netdev);
                        mod_timer(&adapter->phy_info_timer,
                                  round_jiffies(jiffies + 2 * HZ));
                        adapter->smartspeed = 0;
                }
        } else {
                if (netif_carrier_ok(netdev)) {
                        adapter->link_speed = 0;
                        adapter->link_duplex = 0;
                        printk(KERN_INFO "e1000: %s NIC Link is Down\n",
                               netdev->name);
                        netif_carrier_off(netdev);
                        mod_timer(&adapter->phy_info_timer,
                                  round_jiffies(jiffies + 2 * HZ));
                }

                e1000_smartspeed(adapter);
        }

        e1000_update_stats(adapter);

        hw->tx_packet_delta = adapter->stats.tpt - adapter->tpt_old;
        adapter->tpt_old = adapter->stats.tpt;
        hw->collision_delta = adapter->stats.colc - adapter->colc_old;
        adapter->colc_old = adapter->stats.colc;

        adapter->gorcl = adapter->stats.gorcl - adapter->gorcl_old;
        adapter->gorcl_old = adapter->stats.gorcl;
        adapter->gotcl = adapter->stats.gotcl - adapter->gotcl_old;
        adapter->gotcl_old = adapter->stats.gotcl;

        e1000_update_adaptive(hw);

        if (!netif_carrier_ok(netdev)) {
                if (E1000_DESC_UNUSED(txdr) + 1 < txdr->count) {
                        /* We've lost link, so the controller stops DMA,
                         * but we've got queued Tx work that's never going
                         * to get done, so reset controller to flush Tx.
                         * (Do the reset outside of interrupt context). */
                        adapter->tx_timeout_count++;
                        schedule_work(&adapter->reset_task);
                        /* return immediately since reset is imminent */
                        return;
                }
        }

        /* Cause software interrupt to ensure rx ring is cleaned */
        ew32(ICS, E1000_ICS_RXDMT0);

        /* Force detection of hung controller every watchdog period */
        adapter->detect_tx_hung = true;

        /* Reset the timer */
        mod_timer(&adapter->watchdog_timer, round_jiffies(jiffies + 2 * HZ));
}

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

/**
 * e1000_update_itr - update the dynamic ITR value based on statistics
 *      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 e1000_param.c)
 * @adapter: pointer to adapter
 * @itr_setting: current adapter->itr
 * @packets: the number of packets during this measurement interval
 * @bytes: the number of bytes during this measurement interval
 **/
static unsigned int e1000_update_itr(struct e1000_adapter *adapter,
                                     u16 itr_setting, int packets, int bytes)
{
        unsigned int retval = itr_setting;
        struct e1000_hw *hw = &adapter->hw;

        if (unlikely(hw->mac_type < e1000_82540))
                goto update_itr_done;

        if (packets == 0)
                goto update_itr_done;

        switch (itr_setting) {
        case lowest_latency:
                /* jumbo frames get bulk treatment*/
                if (bytes/packets > 8000)
                        retval = bulk_latency;
                else if ((packets < 5) && (bytes > 512))
                        retval = low_latency;
                break;
        case low_latency:  /* 50 usec aka 20000 ints/s */
                if (bytes > 10000) {
                        /* jumbo frames need bulk latency setting */
                        if (bytes/packets > 8000)
                                retval = bulk_latency;
                        else if ((packets < 10) || ((bytes/packets) > 1200))
                                retval = bulk_latency;
                        else if ((packets > 35))
                                retval = lowest_latency;
                } else if (bytes/packets > 2000)
                        retval = bulk_latency;
                else if (packets <= 2 && bytes < 512)
                        retval = lowest_latency;
                break;
        case bulk_latency: /* 250 usec aka 4000 ints/s */
                if (bytes > 25000) {
                        if (packets > 35)
                                retval = low_latency;
                } else if (bytes < 6000) {
                        retval = low_latency;
                }
                break;
        }

update_itr_done:
        return retval;
}

static void e1000_set_itr(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u16 current_itr;
        u32 new_itr = adapter->itr;

        if (unlikely(hw->mac_type < e1000_82540))
                return;

        /* for non-gigabit speeds, just fix the interrupt rate at 4000 */
        if (unlikely(adapter->link_speed != SPEED_1000)) {
                current_itr = 0;
                new_itr = 4000;
                goto set_itr_now;
        }

        adapter->tx_itr = e1000_update_itr(adapter,
                                    adapter->tx_itr,
                                    adapter->total_tx_packets,
                                    adapter->total_tx_bytes);
        /* conservative mode (itr 3) eliminates the lowest_latency setting */
        if (adapter->itr_setting == 3 && adapter->tx_itr == lowest_latency)
                adapter->tx_itr = low_latency;

        adapter->rx_itr = e1000_update_itr(adapter,
                                    adapter->rx_itr,
                                    adapter->total_rx_packets,
                                    adapter->total_rx_bytes);
        /* conservative mode (itr 3) eliminates the lowest_latency setting */
        if (adapter->itr_setting == 3 && adapter->rx_itr == lowest_latency)
                adapter->rx_itr = low_latency;

        current_itr = max(adapter->rx_itr, adapter->tx_itr);

        switch (current_itr) {
        /* counts and packets in update_itr are dependent on these numbers */
        case lowest_latency:
                new_itr = 70000;
                break;
        case low_latency:
                new_itr = 20000; /* aka hwitr = ~200 */
                break;
        case bulk_latency:
                new_itr = 4000;
                break;
        default:
                break;
        }

set_itr_now:
        if (new_itr != adapter->itr) {
                /* this attempts to bias the interrupt rate towards Bulk
                 * by adding intermediate steps when interrupt rate is
                 * increasing */
                new_itr = new_itr > adapter->itr ?
                             min(adapter->itr + (new_itr >> 2), new_itr) :
                             new_itr;
                adapter->itr = new_itr;
                ew32(ITR, 1000000000 / (new_itr * 256));
        }

        return;
}

#define E1000_TX_FLAGS_CSUM             0x00000001
#define E1000_TX_FLAGS_VLAN             0x00000002
#define E1000_TX_FLAGS_TSO              0x00000004
#define E1000_TX_FLAGS_IPV4             0x00000008
#define E1000_TX_FLAGS_VLAN_MASK        0xffff0000
#define E1000_TX_FLAGS_VLAN_SHIFT       16

static int e1000_tso(struct e1000_adapter *adapter,
                     struct e1000_tx_ring *tx_ring, struct sk_buff *skb)
{
        struct e1000_context_desc *context_desc;
        struct e1000_buffer *buffer_info;
        unsigned int i;
        u32 cmd_length = 0;
        u16 ipcse = 0, tucse, mss;
        u8 ipcss, ipcso, tucss, tucso, hdr_len;
        int err;

        if (skb_is_gso(skb)) {
                if (skb_header_cloned(skb)) {
                        err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
                        if (err)
                                return err;
                }

                hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
                mss = skb_shinfo(skb)->gso_size;
                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);
                        cmd_length = E1000_TXD_CMD_IP;
                        ipcse = skb_transport_offset(skb) - 1;
                } else if (skb->protocol == htons(ETH_P_IPV6)) {
                        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);
                        ipcse = 0;
                }
                ipcss = skb_network_offset(skb);
                ipcso = (void *)&(ip_hdr(skb)->check) - (void *)skb->data;
                tucss = skb_transport_offset(skb);
                tucso = (void *)&(tcp_hdr(skb)->check) - (void *)skb->data;
                tucse = 0;

                cmd_length |= (E1000_TXD_CMD_DEXT | E1000_TXD_CMD_TSE |
                               E1000_TXD_CMD_TCP | (skb->len - (hdr_len)));

                i = tx_ring->next_to_use;
                context_desc = E1000_CONTEXT_DESC(*tx_ring, i);
                buffer_info = &tx_ring->buffer_info[i];

                context_desc->lower_setup.ip_fields.ipcss  = ipcss;
                context_desc->lower_setup.ip_fields.ipcso  = ipcso;
                context_desc->lower_setup.ip_fields.ipcse  = cpu_to_le16(ipcse);
                context_desc->upper_setup.tcp_fields.tucss = tucss;
                context_desc->upper_setup.tcp_fields.tucso = tucso;
                context_desc->upper_setup.tcp_fields.tucse = cpu_to_le16(tucse);
                context_desc->tcp_seg_setup.fields.mss     = cpu_to_le16(mss);
                context_desc->tcp_seg_setup.fields.hdr_len = hdr_len;
                context_desc->cmd_and_length = cpu_to_le32(cmd_length);

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

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

                return true;
        }
        return false;
}

static bool e1000_tx_csum(struct e1000_adapter *adapter,
                          struct e1000_tx_ring *tx_ring, struct sk_buff *skb)
{
        struct e1000_context_desc *context_desc;
        struct e1000_buffer *buffer_info;
        unsigned int i;
        u8 css;
        u32 cmd_len = E1000_TXD_CMD_DEXT;

        if (skb->ip_summed != CHECKSUM_PARTIAL)
                return false;

        switch (skb->protocol) {
        case cpu_to_be16(ETH_P_IP):
                if (ip_hdr(skb)->protocol == IPPROTO_TCP)
                        cmd_len |= E1000_TXD_CMD_TCP;
                break;
        case cpu_to_be16(ETH_P_IPV6):
                /* XXX not handling all IPV6 headers */
                if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
                        cmd_len |= E1000_TXD_CMD_TCP;
                break;
        default:
                if (unlikely(net_ratelimit()))
                        DPRINTK(DRV, WARNING,
                                "checksum_partial proto=%x!\n", skb->protocol);
                break;
        }

        css = skb_transport_offset(skb);

        i = tx_ring->next_to_use;
        buffer_info = &tx_ring->buffer_info[i];
        context_desc = E1000_CONTEXT_DESC(*tx_ring, i);

        context_desc->lower_setup.ip_config = 0;
        context_desc->upper_setup.tcp_fields.tucss = css;
        context_desc->upper_setup.tcp_fields.tucso =
                css + skb->csum_offset;
        context_desc->upper_setup.tcp_fields.tucse = 0;
        context_desc->tcp_seg_setup.data = 0;
        context_desc->cmd_and_length = cpu_to_le32(cmd_len);

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

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

        return true;
}

#define E1000_MAX_TXD_PWR       12
#define E1000_MAX_DATA_PER_TXD  (1<<E1000_MAX_TXD_PWR)

static int e1000_tx_map(struct e1000_adapter *adapter,
                        struct e1000_tx_ring *tx_ring,
                        struct sk_buff *skb, unsigned int first,
                        unsigned int max_per_txd, unsigned int nr_frags,
                        unsigned int mss)
{
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_buffer *buffer_info;
        unsigned int len = skb_headlen(skb);
        unsigned int offset, size, count = 0, i;
        unsigned int f;
        dma_addr_t *map;

        i = tx_ring->next_to_use;

        if (skb_dma_map(&adapter->pdev->dev, skb, DMA_TO_DEVICE)) {
                dev_err(&adapter->pdev->dev, "TX DMA map failed\n");
                return 0;
        }

        map = skb_shinfo(skb)->dma_maps;
        offset = 0;

        while (len) {
                buffer_info = &tx_ring->buffer_info[i];
                size = min(len, max_per_txd);
                /* Workaround for Controller erratum --
                 * descriptor for non-tso packet in a linear SKB that follows a
                 * tso gets written back prematurely before the data is fully
                 * DMA'd to the controller */
                if (!skb->data_len && tx_ring->last_tx_tso &&
                    !skb_is_gso(skb)) {
                        tx_ring->last_tx_tso = 0;
                        size -= 4;
                }

                /* Workaround for premature desc write-backs
                 * in TSO mode.  Append 4-byte sentinel desc */
                if (unlikely(mss && !nr_frags && size == len && size > 8))
                        size -= 4;
                /* work-around for errata 10 and it applies
                 * to all controllers in PCI-X mode
                 * The fix is to make sure that the first descriptor of a
                 * packet is smaller than 2048 - 16 - 16 (or 2016) bytes
                 */
                if (unlikely((hw->bus_type == e1000_bus_type_pcix) &&
                                (size > 2015) && count == 0))
                        size = 2015;

                /* Workaround for potential 82544 hang in PCI-X.  Avoid
                 * terminating buffers within evenly-aligned dwords. */
                if (unlikely(adapter->pcix_82544 &&
                   !((unsigned long)(skb->data + offset + size - 1) & 4) &&
                   size > 4))
                        size -= 4;

                buffer_info->length = size;
                buffer_info->dma = skb_shinfo(skb)->dma_head + offset;
                buffer_info->time_stamp = jiffies;
                buffer_info->next_to_watch = i;

                len -= size;
                offset += size;
                count++;
                if (len) {
                        i++;
                        if (unlikely(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 = 0;

                while (len) {
                        i++;
                        if (unlikely(i == tx_ring->count))
                                i = 0;

                        buffer_info = &tx_ring->buffer_info[i];
                        size = min(len, max_per_txd);
                        /* Workaround for premature desc write-backs
                         * in TSO mode.  Append 4-byte sentinel desc */
                        if (unlikely(mss && f == (nr_frags-1) && size == len && size > 8))
                                size -= 4;
                        /* Workaround for potential 82544 hang in PCI-X.
                         * Avoid terminating buffers within evenly-aligned
                         * dwords. */
                        if (unlikely(adapter->pcix_82544 &&
                           !((unsigned long)(frag->page+offset+size-1) & 4) &&
                           size > 4))
                                size -= 4;

                        buffer_info->length = size;
                        buffer_info->dma = map[f] + offset;
                        buffer_info->time_stamp = jiffies;
                        buffer_info->next_to_watch = i;

                        len -= size;
                        offset += size;
                        count++;
                }
        }

        tx_ring->buffer_info[i].skb = skb;
        tx_ring->buffer_info[first].next_to_watch = i;

        return count;
}

static void e1000_tx_queue(struct e1000_adapter *adapter,
                           struct e1000_tx_ring *tx_ring, int tx_flags,
                           int count)
{
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_tx_desc *tx_desc = NULL;
        struct e1000_buffer *buffer_info;
        u32 txd_upper = 0, txd_lower = E1000_TXD_CMD_IFCS;
        unsigned int i;

        if (likely(tx_flags & E1000_TX_FLAGS_TSO)) {
                txd_lower |= E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D |
                             E1000_TXD_CMD_TSE;
                txd_upper |= E1000_TXD_POPTS_TXSM << 8;

                if (likely(tx_flags & E1000_TX_FLAGS_IPV4))
                        txd_upper |= E1000_TXD_POPTS_IXSM << 8;
        }

        if (likely(tx_flags & E1000_TX_FLAGS_CSUM)) {
                txd_lower |= E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
                txd_upper |= E1000_TXD_POPTS_TXSM << 8;
        }

        if (unlikely(tx_flags & E1000_TX_FLAGS_VLAN)) {
                txd_lower |= E1000_TXD_CMD_VLE;
                txd_upper |= (tx_flags & E1000_TX_FLAGS_VLAN_MASK);
        }

        i = tx_ring->next_to_use;

        while (count--) {
                buffer_info = &tx_ring->buffer_info[i];
                tx_desc = E1000_TX_DESC(*tx_ring, i);
                tx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
                tx_desc->lower.data =
                        cpu_to_le32(txd_lower | buffer_info->length);
                tx_desc->upper.data = cpu_to_le32(txd_upper);
                if (unlikely(++i == tx_ring->count)) i = 0;
        }

        tx_desc->lower.data |= cpu_to_le32(adapter->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, hw->hw_addr + tx_ring->tdt);
        /* we need this if more than one processor can write to our tail
         * at a time, it syncronizes IO on IA64/Altix systems */
        mmiowb();
}

/**
 * 82547 workaround to avoid controller hang in half-duplex environment.
 * The workaround is to avoid queuing a large packet that would span
 * the internal Tx FIFO ring boundary by notifying the stack to resend
 * the packet at a later time.  This gives the Tx FIFO an opportunity to
 * flush all packets.  When that occurs, we reset the Tx FIFO pointers
 * to the beginning of the Tx FIFO.
 **/

#define E1000_FIFO_HDR                  0x10
#define E1000_82547_PAD_LEN             0x3E0

static int e1000_82547_fifo_workaround(struct e1000_adapter *adapter,
                                       struct sk_buff *skb)
{
        u32 fifo_space = adapter->tx_fifo_size - adapter->tx_fifo_head;
        u32 skb_fifo_len = skb->len + E1000_FIFO_HDR;

        skb_fifo_len = ALIGN(skb_fifo_len, E1000_FIFO_HDR);

        if (adapter->link_duplex != HALF_DUPLEX)
                goto no_fifo_stall_required;

        if (atomic_read(&adapter->tx_fifo_stall))
                return 1;

        if (skb_fifo_len >= (E1000_82547_PAD_LEN + fifo_space)) {
                atomic_set(&adapter->tx_fifo_stall, 1);
                return 1;
        }

no_fifo_stall_required:
        adapter->tx_fifo_head += skb_fifo_len;
        if (adapter->tx_fifo_head >= adapter->tx_fifo_size)
                adapter->tx_fifo_head -= adapter->tx_fifo_size;
        return 0;
}

static int __e1000_maybe_stop_tx(struct net_device *netdev, int size)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_tx_ring *tx_ring = adapter->tx_ring;

        netif_stop_queue(netdev);
        /* 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(E1000_DESC_UNUSED(tx_ring) < size))
                return -EBUSY;

        /* A reprieve! */
        netif_start_queue(netdev);
        ++adapter->restart_queue;
        return 0;
}

static int e1000_maybe_stop_tx(struct net_device *netdev,
                               struct e1000_tx_ring *tx_ring, int size)
{
        if (likely(E1000_DESC_UNUSED(tx_ring) >= size))
                return 0;
        return __e1000_maybe_stop_tx(netdev, size);
}

#define TXD_USE_COUNT(S, X) (((S) >> (X)) + 1 )
static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
                                    struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_tx_ring *tx_ring;
        unsigned int first, max_per_txd = E1000_MAX_DATA_PER_TXD;
        unsigned int max_txd_pwr = E1000_MAX_TXD_PWR;
        unsigned int tx_flags = 0;
        unsigned int len = skb->len - skb->data_len;
        unsigned int nr_frags;
        unsigned int mss;
        int count = 0;
        int tso;
        unsigned int f;

        /* This goes back to the question of how to logically map a tx queue
         * to a flow.  Right now, performance is impacted slightly negatively
         * if using multiple tx queues.  If the stack breaks away from a
         * single qdisc implementation, we can look at this again. */
        tx_ring = adapter->tx_ring;

        if (unlikely(skb->len <= 0)) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        mss = skb_shinfo(skb)->gso_size;
        /* The controller does a simple calculation to
         * make sure there is enough room in the FIFO before
         * initiating the DMA for each buffer.  The calc is:
         * 4 = ceil(buffer len/mss).  To make sure we don't
         * overrun the FIFO, adjust the max buffer len if mss
         * drops. */
        if (mss) {
                u8 hdr_len;
                max_per_txd = min(mss << 2, max_per_txd);
                max_txd_pwr = fls(max_per_txd) - 1;

                hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
                if (skb->data_len && hdr_len == len) {
                        switch (hw->mac_type) {
                                unsigned int pull_size;
                        case e1000_82544:
                                /* Make sure we have room to chop off 4 bytes,
                                 * and that the end alignment will work out to
                                 * this hardware's requirements
                                 * NOTE: this is a TSO only workaround
                                 * if end byte alignment not correct move us
                                 * into the next dword */
                                if ((unsigned long)(skb_tail_pointer(skb) - 1) & 4)
                                        break;
                                /* fall through */
                                pull_size = min((unsigned int)4, skb->data_len);
                                if (!__pskb_pull_tail(skb, pull_size)) {
                                        DPRINTK(DRV, ERR,
                                                "__pskb_pull_tail failed.\n");
                                        dev_kfree_skb_any(skb);
                                        return NETDEV_TX_OK;
                                }
                                len = skb->len - skb->data_len;
                                break;
                        default:
                                /* do nothing */
                                break;
                        }
                }
        }

        /* reserve a descriptor for the offload context */
        if ((mss) || (skb->ip_summed == CHECKSUM_PARTIAL))
                count++;
        count++;

        /* Controller Erratum workaround */
        if (!skb->data_len && tx_ring->last_tx_tso && !skb_is_gso(skb))
                count++;

        count += TXD_USE_COUNT(len, max_txd_pwr);

        if (adapter->pcix_82544)
                count++;

        /* work-around for errata 10 and it applies to all controllers
         * in PCI-X mode, so add one more descriptor to the count
         */
        if (unlikely((hw->bus_type == e1000_bus_type_pcix) &&
                        (len > 2015)))
                count++;

        nr_frags = skb_shinfo(skb)->nr_frags;
        for (f = 0; f < nr_frags; f++)
                count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size,
                                       max_txd_pwr);
        if (adapter->pcix_82544)
                count += nr_frags;

        /* need: count + 2 desc gap to keep tail from touching
         * head, otherwise try next time */
        if (unlikely(e1000_maybe_stop_tx(netdev, tx_ring, count + 2)))
                return NETDEV_TX_BUSY;

        if (unlikely(hw->mac_type == e1000_82547)) {
                if (unlikely(e1000_82547_fifo_workaround(adapter, skb))) {
                        netif_stop_queue(netdev);
                        mod_timer(&adapter->tx_fifo_stall_timer, jiffies + 1);
                        return NETDEV_TX_BUSY;
                }
        }

        if (unlikely(adapter->vlgrp && vlan_tx_tag_present(skb))) {
                tx_flags |= E1000_TX_FLAGS_VLAN;
                tx_flags |= (vlan_tx_tag_get(skb) << E1000_TX_FLAGS_VLAN_SHIFT);
        }

        first = tx_ring->next_to_use;

        tso = e1000_tso(adapter, tx_ring, skb);
        if (tso < 0) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        if (likely(tso)) {
                tx_ring->last_tx_tso = 1;
                tx_flags |= E1000_TX_FLAGS_TSO;
        } else if (likely(e1000_tx_csum(adapter, tx_ring, skb)))
                tx_flags |= E1000_TX_FLAGS_CSUM;

        if (likely(skb->protocol == htons(ETH_P_IP)))
                tx_flags |= E1000_TX_FLAGS_IPV4;

        count = e1000_tx_map(adapter, tx_ring, skb, first, max_per_txd,
                             nr_frags, mss);

        if (count) {
                e1000_tx_queue(adapter, tx_ring, tx_flags, count);
                /* Make sure there is space in the ring for the next send. */
                e1000_maybe_stop_tx(netdev, tx_ring, MAX_SKB_FRAGS + 2);

        } else {
                dev_kfree_skb_any(skb);
                tx_ring->buffer_info[first].time_stamp = 0;
                tx_ring->next_to_use = first;
        }

        return NETDEV_TX_OK;
}

/**
 * e1000_tx_timeout - Respond to a Tx Hang
 * @netdev: network interface device structure
 **/

static void e1000_tx_timeout(struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);

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

static void e1000_reset_task(struct work_struct *work)
{
        struct e1000_adapter *adapter =
                container_of(work, struct e1000_adapter, reset_task);

        e1000_reinit_locked(adapter);
}

/**
 * e1000_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 *e1000_get_stats(struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);

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

/**
 * e1000_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 e1000_change_mtu(struct net_device *netdev, int new_mtu)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        int max_frame = new_mtu + ENET_HEADER_SIZE + ETHERNET_FCS_SIZE;

        if ((max_frame < MINIMUM_ETHERNET_FRAME_SIZE) ||
            (max_frame > MAX_JUMBO_FRAME_SIZE)) {
                DPRINTK(PROBE, ERR, "Invalid MTU setting\n");
                return -EINVAL;
        }

        /* Adapter-specific max frame size limits. */
        switch (hw->mac_type) {
        case e1000_undefined ... e1000_82542_rev2_1:
                if (max_frame > (ETH_FRAME_LEN + ETH_FCS_LEN)) {
                        DPRINTK(PROBE, ERR, "Jumbo Frames not supported.\n");
                        return -EINVAL;
                }
                break;
        default:
                /* Capable of supporting up to MAX_JUMBO_FRAME_SIZE limit. */
                break;
        }

        /* NOTE: netdev_alloc_skb reserves 16 bytes, and typically NET_IP_ALIGN
         * means we reserve 2 more, this pushes us to allocate from the next
         * larger slab size.
         * i.e. RXBUFFER_2048 --> size-4096 slab
         *  however with the new *_jumbo_rx* routines, jumbo receives will use
         *  fragmented skbs */

        if (max_frame <= E1000_RXBUFFER_256)
                adapter->rx_buffer_len = E1000_RXBUFFER_256;
        else if (max_frame <= E1000_RXBUFFER_512)
                adapter->rx_buffer_len = E1000_RXBUFFER_512;
        else if (max_frame <= E1000_RXBUFFER_1024)
                adapter->rx_buffer_len = E1000_RXBUFFER_1024;
        else if (max_frame <= E1000_RXBUFFER_2048)
                adapter->rx_buffer_len = E1000_RXBUFFER_2048;
        else
#if (PAGE_SIZE >= E1000_RXBUFFER_16384)
                adapter->rx_buffer_len = E1000_RXBUFFER_16384;
#elif (PAGE_SIZE >= E1000_RXBUFFER_4096)
                adapter->rx_buffer_len = PAGE_SIZE;
#endif

        /* adjust allocation if LPE protects us, and we aren't using SBP */
        if (!hw->tbi_compatibility_on &&
            ((max_frame == (ETH_FRAME_LEN + ETH_FCS_LEN)) ||
             (max_frame == MAXIMUM_ETHERNET_VLAN_SIZE)))
                adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;

        netdev->mtu = new_mtu;
        hw->max_frame_size = max_frame;

        if (netif_running(netdev))
                e1000_reinit_locked(adapter);

        return 0;
}

/**
 * e1000_update_stats - Update the board statistics counters
 * @adapter: board private structure
 **/

void e1000_update_stats(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct pci_dev *pdev = adapter->pdev;
        unsigned long flags;
        u16 phy_tmp;

#define PHY_IDLE_ERROR_COUNT_MASK 0x00FF

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

        spin_lock_irqsave(&adapter->stats_lock, flags);

        /* these counters are modified from e1000_tbi_adjust_stats,
         * called from the interrupt context, so they must only
         * be written while holding adapter->stats_lock
         */

        adapter->stats.crcerrs += er32(CRCERRS);
        adapter->stats.gprc += er32(GPRC);
        adapter->stats.gorcl += er32(GORCL);
        adapter->stats.gorch += er32(GORCH);
        adapter->stats.bprc += er32(BPRC);
        adapter->stats.mprc += er32(MPRC);
        adapter->stats.roc += er32(ROC);

        adapter->stats.prc64 += er32(PRC64);
        adapter->stats.prc127 += er32(PRC127);
        adapter->stats.prc255 += er32(PRC255);
        adapter->stats.prc511 += er32(PRC511);
        adapter->stats.prc1023 += er32(PRC1023);
        adapter->stats.prc1522 += er32(PRC1522);

        adapter->stats.symerrs += er32(SYMERRS);
        adapter->stats.mpc += er32(MPC);
        adapter->stats.scc += er32(SCC);
        adapter->stats.ecol += er32(ECOL);
        adapter->stats.mcc += er32(MCC);
        adapter->stats.latecol += er32(LATECOL);
        adapter->stats.dc += er32(DC);
        adapter->stats.sec += er32(SEC);
        adapter->stats.rlec += er32(RLEC);
        adapter->stats.xonrxc += er32(XONRXC);
        adapter->stats.xontxc += er32(XONTXC);
        adapter->stats.xoffrxc += er32(XOFFRXC);
        adapter->stats.xofftxc += er32(XOFFTXC);
        adapter->stats.fcruc += er32(FCRUC);
        adapter->stats.gptc += er32(GPTC);
        adapter->stats.gotcl += er32(GOTCL);
        adapter->stats.gotch += er32(GOTCH);
        adapter->stats.rnbc += er32(RNBC);
        adapter->stats.ruc += er32(RUC);
        adapter->stats.rfc += er32(RFC);
        adapter->stats.rjc += er32(RJC);
        adapter->stats.torl += er32(TORL);
        adapter->stats.torh += er32(TORH);
        adapter->stats.totl += er32(TOTL);
        adapter->stats.toth += er32(TOTH);
        adapter->stats.tpr += er32(TPR);

        adapter->stats.ptc64 += er32(PTC64);
        adapter->stats.ptc127 += er32(PTC127);
        adapter->stats.ptc255 += er32(PTC255);
        adapter->stats.ptc511 += er32(PTC511);
        adapter->stats.ptc1023 += er32(PTC1023);
        adapter->stats.ptc1522 += er32(PTC1522);

        adapter->stats.mptc += er32(MPTC);
        adapter->stats.bptc += er32(BPTC);

        /* used for adaptive IFS */

        hw->tx_packet_delta = er32(TPT);
        adapter->stats.tpt += hw->tx_packet_delta;
        hw->collision_delta = er32(COLC);
        adapter->stats.colc += hw->collision_delta;

        if (hw->mac_type >= e1000_82543) {
                adapter->stats.algnerrc += er32(ALGNERRC);
                adapter->stats.rxerrc += er32(RXERRC);
                adapter->stats.tncrs += er32(TNCRS);
                adapter->stats.cexterr += er32(CEXTERR);
                adapter->stats.tsctc += er32(TSCTC);
                adapter->stats.tsctfc += er32(TSCTFC);
        }

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

        /* Rx Errors */

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

        /* Tx Errors */
        adapter->stats.txerrc = adapter->stats.ecol + adapter->stats.latecol;
        adapter->net_stats.tx_errors = adapter->stats.txerrc;
        adapter->net_stats.tx_aborted_errors = adapter->stats.ecol;
        adapter->net_stats.tx_window_errors = adapter->stats.latecol;
        adapter->net_stats.tx_carrier_errors = adapter->stats.tncrs;
        if (hw->bad_tx_carr_stats_fd &&
            adapter->link_duplex == FULL_DUPLEX) {
                adapter->net_stats.tx_carrier_errors = 0;
                adapter->stats.tncrs = 0;
        }

        /* Tx Dropped needs to be maintained elsewhere */

        /* Phy Stats */
        if (hw->media_type == e1000_media_type_copper) {
                if ((adapter->link_speed == SPEED_1000) &&
                   (!e1000_read_phy_reg(hw, PHY_1000T_STATUS, &phy_tmp))) {
                        phy_tmp &= PHY_IDLE_ERROR_COUNT_MASK;
                        adapter->phy_stats.idle_errors += phy_tmp;
                }

                if ((hw->mac_type <= e1000_82546) &&
                   (hw->phy_type == e1000_phy_m88) &&
                   !e1000_read_phy_reg(hw, M88E1000_RX_ERR_CNTR, &phy_tmp))
                        adapter->phy_stats.receive_errors += phy_tmp;
        }

        /* Management Stats */
        if (hw->has_smbus) {
                adapter->stats.mgptc += er32(MGTPTC);
                adapter->stats.mgprc += er32(MGTPRC);
                adapter->stats.mgpdc += er32(MGTPDC);
        }

        spin_unlock_irqrestore(&adapter->stats_lock, flags);
}

/**
 * e1000_intr - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 **/

static irqreturn_t e1000_intr(int irq, void *data)
{
        struct net_device *netdev = data;
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 icr = er32(ICR);

        if (unlikely((!icr) || test_bit(__E1000_DOWN, &adapter->flags)))
                return IRQ_NONE;  /* Not our interrupt */

        if (unlikely(icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC))) {
                hw->get_link_status = 1;
                /* guard against interrupt when we're going down */
                if (!test_bit(__E1000_DOWN, &adapter->flags))
                        mod_timer(&adapter->watchdog_timer, jiffies + 1);
        }

        /* disable interrupts, without the synchronize_irq bit */
        ew32(IMC, ~0);
        E1000_WRITE_FLUSH();

        if (likely(napi_schedule_prep(&adapter->napi))) {
                adapter->total_tx_bytes = 0;
                adapter->total_tx_packets = 0;
                adapter->total_rx_bytes = 0;
                adapter->total_rx_packets = 0;
                __napi_schedule(&adapter->napi);
        } else {
                /* this really should not happen! if it does it is basically a
                 * bug, but not a hard error, so enable ints and continue */
                if (!test_bit(__E1000_DOWN, &adapter->flags))
                        e1000_irq_enable(adapter);
        }

        return IRQ_HANDLED;
}

/**
 * e1000_clean - NAPI Rx polling callback
 * @adapter: board private structure
 **/
static int e1000_clean(struct napi_struct *napi, int budget)
{
        struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter, napi);
        struct net_device *poll_dev = adapter->netdev;
        int tx_cleaned = 0, work_done = 0;

        adapter = netdev_priv(poll_dev);

        tx_cleaned = e1000_clean_tx_irq(adapter, &adapter->tx_ring[0]);

        adapter->clean_rx(adapter, &adapter->rx_ring[0],
                          &work_done, budget);

        if (!tx_cleaned)
                work_done = budget;

        /* If budget not fully consumed, exit the polling mode */
        if (work_done < budget) {
                if (likely(adapter->itr_setting & 3))
                        e1000_set_itr(adapter);
                napi_complete(napi);
                if (!test_bit(__E1000_DOWN, &adapter->flags))
                        e1000_irq_enable(adapter);
        }

        return work_done;
}

/**
 * e1000_clean_tx_irq - Reclaim resources after transmit completes
 * @adapter: board private structure
 **/
static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
                               struct e1000_tx_ring *tx_ring)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct e1000_tx_desc *tx_desc, *eop_desc;
        struct e1000_buffer *buffer_info;
        unsigned int i, eop;
        unsigned int count = 0;
        unsigned int total_tx_bytes=0, total_tx_packets=0;

        i = tx_ring->next_to_clean;
        eop = tx_ring->buffer_info[i].next_to_watch;
        eop_desc = E1000_TX_DESC(*tx_ring, eop);

        while ((eop_desc->upper.data & cpu_to_le32(E1000_TXD_STAT_DD)) &&
               (count < tx_ring->count)) {
                bool cleaned = false;
                for ( ; !cleaned; count++) {
                        tx_desc = E1000_TX_DESC(*tx_ring, i);
                        buffer_info = &tx_ring->buffer_info[i];
                        cleaned = (i == eop);

                        if (cleaned) {
                                struct sk_buff *skb = 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;
                        }
                        e1000_unmap_and_free_tx_resource(adapter, buffer_info);
                        tx_desc->upper.data = 0;

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

                eop = tx_ring->buffer_info[i].next_to_watch;
                eop_desc = E1000_TX_DESC(*tx_ring, eop);
        }

        tx_ring->next_to_clean = i;

#define TX_WAKE_THRESHOLD 32
        if (unlikely(count && netif_carrier_ok(netdev) &&
                     E1000_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD)) {
                /* Make sure that anybody stopping the queue after this
                 * sees the new next_to_clean.
                 */
                smp_mb();
                if (netif_queue_stopped(netdev)) {
                        netif_wake_queue(netdev);
                        ++adapter->restart_queue;
                }
        }

        if (adapter->detect_tx_hung) {
                /* 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->buffer_info[i].time_stamp &&
                    time_after(jiffies, tx_ring->buffer_info[i].time_stamp +
                               (adapter->tx_timeout_factor * HZ))
                    && !(er32(STATUS) & E1000_STATUS_TXOFF)) {

                        /* detected Tx unit hang */
                        DPRINTK(DRV, ERR, "Detected Tx Unit Hang\n"
                                        "  Tx Queue             <%lu>\n"
                                        "  TDH                  <%x>\n"
                                        "  TDT                  <%x>\n"
                                        "  next_to_use          <%x>\n"
                                        "  next_to_clean        <%x>\n"
                                        "buffer_info[next_to_clean]\n"
                                        "  time_stamp           <%lx>\n"
                                        "  next_to_watch        <%x>\n"
                                        "  jiffies              <%lx>\n"
                                        "  next_to_watch.status <%x>\n",
                                (unsigned long)((tx_ring - adapter->tx_ring) /
                                        sizeof(struct e1000_tx_ring)),
                                readl(hw->hw_addr + tx_ring->tdh),
                                readl(hw->hw_addr + tx_ring->tdt),
                                tx_ring->next_to_use,
                                tx_ring->next_to_clean,
                                tx_ring->buffer_info[i].time_stamp,
                                eop,
                                jiffies,
                                eop_desc->upper.fields.status);
                        netif_stop_queue(netdev);
                }
        }
        adapter->total_tx_bytes += total_tx_bytes;
        adapter->total_tx_packets += total_tx_packets;
        adapter->net_stats.tx_bytes += total_tx_bytes;
        adapter->net_stats.tx_packets += total_tx_packets;
        return (count < tx_ring->count);
}

/**
 * e1000_rx_checksum - Receive Checksum Offload for 82543
 * @adapter:     board private structure
 * @status_err:  receive descriptor status and error fields
 * @csum:        receive descriptor csum field
 * @sk_buff:     socket buffer with received data
 **/

static void e1000_rx_checksum(struct e1000_adapter *adapter, u32 status_err,
                              u32 csum, struct sk_buff *skb)
{
        struct e1000_hw *hw = &adapter->hw;
        u16 status = (u16)status_err;
        u8 errors = (u8)(status_err >> 24);
        skb->ip_summed = CHECKSUM_NONE;

        /* 82543 or newer only */
        if (unlikely(hw->mac_type < e1000_82543)) return;
        /* Ignore Checksum bit is set */
        if (unlikely(status & E1000_RXD_STAT_IXSM)) return;
        /* TCP/UDP checksum error bit is set */
        if (unlikely(errors & E1000_RXD_ERR_TCPE)) {
                /* let the stack verify checksum errors */
                adapter->hw_csum_err++;
                return;
        }
        /* TCP/UDP Checksum has not been calculated */
        if (!(status & E1000_RXD_STAT_TCPCS))
                return;

        /* It must be a TCP or UDP packet with a valid checksum */
        if (likely(status & E1000_RXD_STAT_TCPCS)) {
                /* TCP checksum is good */
                skb->ip_summed = CHECKSUM_UNNECESSARY;
        }
        adapter->hw_csum_good++;
}

/**
 * e1000_consume_page - helper function
 **/
static void e1000_consume_page(struct e1000_buffer *bi, struct sk_buff *skb,
                               u16 length)
{
        bi->page = NULL;
        skb->len += length;
        skb->data_len += length;
        skb->truesize += length;
}

/**
 * e1000_receive_skb - helper function to handle rx indications
 * @adapter: board private structure
 * @status: descriptor status field as written by hardware
 * @vlan: descriptor vlan field as written by hardware (no le/be conversion)
 * @skb: pointer to sk_buff to be indicated to stack
 */
static void e1000_receive_skb(struct e1000_adapter *adapter, u8 status,
                              __le16 vlan, struct sk_buff *skb)
{
        if (unlikely(adapter->vlgrp && (status & E1000_RXD_STAT_VP))) {
                vlan_hwaccel_receive_skb(skb, adapter->vlgrp,
                                         le16_to_cpu(vlan) &
                                         E1000_RXD_SPC_VLAN_MASK);
        } else {
                netif_receive_skb(skb);
        }
}

/**
 * e1000_clean_jumbo_rx_irq - Send received data up the network stack; legacy
 * @adapter: board private structure
 * @rx_ring: ring to clean
 * @work_done: amount of napi work completed this call
 * @work_to_do: max amount of work allowed for this call to do
 *
 * the return value indicates whether actual cleaning was done, there
 * is no guarantee that everything was cleaned
 */
static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
                                     struct e1000_rx_ring *rx_ring,
                                     int *work_done, int work_to_do)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_rx_desc *rx_desc, *next_rxd;
        struct e1000_buffer *buffer_info, *next_buffer;
        unsigned long irq_flags;
        u32 length;
        unsigned int i;
        int cleaned_count = 0;
        bool cleaned = false;
        unsigned int total_rx_bytes=0, total_rx_packets=0;

        i = rx_ring->next_to_clean;
        rx_desc = E1000_RX_DESC(*rx_ring, i);
        buffer_info = &rx_ring->buffer_info[i];

        while (rx_desc->status & E1000_RXD_STAT_DD) {
                struct sk_buff *skb;
                u8 status;

                if (*work_done >= work_to_do)
                        break;
                (*work_done)++;

                status = rx_desc->status;
                skb = buffer_info->skb;
                buffer_info->skb = NULL;

                if (++i == rx_ring->count) i = 0;
                next_rxd = E1000_RX_DESC(*rx_ring, i);
                prefetch(next_rxd);

                next_buffer = &rx_ring->buffer_info[i];

                cleaned = true;
                cleaned_count++;
                pci_unmap_page(pdev, buffer_info->dma, buffer_info->length,
                               PCI_DMA_FROMDEVICE);
                buffer_info->dma = 0;

                length = le16_to_cpu(rx_desc->length);

                /* errors is only valid for DD + EOP descriptors */
                if (unlikely((status & E1000_RXD_STAT_EOP) &&
                    (rx_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK))) {
                        u8 last_byte = *(skb->data + length - 1);
                        if (TBI_ACCEPT(hw, status, rx_desc->errors, length,
                                       last_byte)) {
                                spin_lock_irqsave(&adapter->stats_lock,
                                                  irq_flags);
                                e1000_tbi_adjust_stats(hw, &adapter->stats,
                                                       length, skb->data);
                                spin_unlock_irqrestore(&adapter->stats_lock,
                                                       irq_flags);
                                length--;
                        } else {
                                /* recycle both page and skb */
                                buffer_info->skb = skb;
                                /* an error means any chain goes out the window
                                 * too */
                                if (rx_ring->rx_skb_top)
                                        dev_kfree_skb(rx_ring->rx_skb_top);
                                rx_ring->rx_skb_top = NULL;
                                goto next_desc;
                        }
                }

#define rxtop rx_ring->rx_skb_top
                if (!(status & E1000_RXD_STAT_EOP)) {
                        /* this descriptor is only the beginning (or middle) */
                        if (!rxtop) {
                                /* this is the beginning of a chain */
                                rxtop = skb;
                                skb_fill_page_desc(rxtop, 0, buffer_info->page,
                                                   0, length);
                        } else {
                                /* this is the middle of a chain */
                                skb_fill_page_desc(rxtop,
                                    skb_shinfo(rxtop)->nr_frags,
                                    buffer_info->page, 0, length);
                                /* re-use the skb, only consumed the page */
                                buffer_info->skb = skb;
                        }
                        e1000_consume_page(buffer_info, rxtop, length);
                        goto next_desc;
                } else {
                        if (rxtop) {
                                /* end of the chain */
                                skb_fill_page_desc(rxtop,
                                    skb_shinfo(rxtop)->nr_frags,
                                    buffer_info->page, 0, length);
                                /* re-use the current skb, we only consumed the
                                 * page */
                                buffer_info->skb = skb;
                                skb = rxtop;
                                rxtop = NULL;
                                e1000_consume_page(buffer_info, skb, length);
                        } else {
                                /* no chain, got EOP, this buf is the packet
                                 * copybreak to save the put_page/alloc_page */
                                if (length <= copybreak &&
                                    skb_tailroom(skb) >= length) {
                                        u8 *vaddr;
                                        vaddr = kmap_atomic(buffer_info->page,
                                                            KM_SKB_DATA_SOFTIRQ);
                                        memcpy(skb_tail_pointer(skb), vaddr, length);
                                        kunmap_atomic(vaddr,
                                                      KM_SKB_DATA_SOFTIRQ);
                                        /* re-use the page, so don't erase
                                         * buffer_info->page */
                                        skb_put(skb, length);
                                } else {
                                        skb_fill_page_desc(skb, 0,
                                                           buffer_info->page, 0,
                                                           length);
                                        e1000_consume_page(buffer_info, skb,
                                                           length);
                                }
                        }
                }

                /* Receive Checksum Offload XXX recompute due to CRC strip? */
                e1000_rx_checksum(adapter,
                                  (u32)(status) |
                                  ((u32)(rx_desc->errors) << 24),
                                  le16_to_cpu(rx_desc->csum), skb);

                pskb_trim(skb, skb->len - 4);

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

                /* eth type trans needs skb->data to point to something */
                if (!pskb_may_pull(skb, ETH_HLEN)) {
                        DPRINTK(DRV, ERR, "pskb_may_pull failed.\n");
                        dev_kfree_skb(skb);
                        goto next_desc;
                }

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

                e1000_receive_skb(adapter, status, rx_desc->special, skb);

next_desc:
                rx_desc->status = 0;

                /* return some buffers to hardware, one at a time is too slow */
                if (unlikely(cleaned_count >= E1000_RX_BUFFER_WRITE)) {
                        adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);
                        cleaned_count = 0;
                }

                /* use prefetched values */
                rx_desc = next_rxd;
                buffer_info = next_buffer;
        }
        rx_ring->next_to_clean = i;

        cleaned_count = E1000_DESC_UNUSED(rx_ring);
        if (cleaned_count)
                adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);

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

/**
 * e1000_clean_rx_irq - Send received data up the network stack; legacy
 * @adapter: board private structure
 * @rx_ring: ring to clean
 * @work_done: amount of napi work completed this call
 * @work_to_do: max amount of work allowed for this call to do
 */
static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
                               struct e1000_rx_ring *rx_ring,
                               int *work_done, int work_to_do)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_rx_desc *rx_desc, *next_rxd;
        struct e1000_buffer *buffer_info, *next_buffer;
        unsigned long flags;
        u32 length;
        unsigned int i;
        int cleaned_count = 0;
        bool cleaned = false;
        unsigned int total_rx_bytes=0, total_rx_packets=0;

        i = rx_ring->next_to_clean;
        rx_desc = E1000_RX_DESC(*rx_ring, i);
        buffer_info = &rx_ring->buffer_info[i];

        while (rx_desc->status & E1000_RXD_STAT_DD) {
                struct sk_buff *skb;
                u8 status;

                if (*work_done >= work_to_do)
                        break;
                (*work_done)++;

                status = rx_desc->status;
                skb = buffer_info->skb;
                buffer_info->skb = NULL;

                prefetch(skb->data - NET_IP_ALIGN);

                if (++i == rx_ring->count) i = 0;
                next_rxd = E1000_RX_DESC(*rx_ring, i);
                prefetch(next_rxd);

                next_buffer = &rx_ring->buffer_info[i];

                cleaned = true;
                cleaned_count++;
                pci_unmap_single(pdev, buffer_info->dma, buffer_info->length,
                                 PCI_DMA_FROMDEVICE);
                buffer_info->dma = 0;

                length = le16_to_cpu(rx_desc->length);
                /* !EOP means multiple descriptors were used to store a single
                 * packet, also make sure the frame isn't just CRC only */
                if (unlikely(!(status & E1000_RXD_STAT_EOP) || (length <= 4))) {
                        /* All receives must fit into a single buffer */
                        E1000_DBG("%s: Receive packet consumed multiple"
                                  " buffers\n", netdev->name);
                        /* recycle */
                        buffer_info->skb = skb;
                        goto next_desc;
                }

                if (unlikely(rx_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK)) {
                        u8 last_byte = *(skb->data + length - 1);
                        if (TBI_ACCEPT(hw, status, rx_desc->errors, length,
                                       last_byte)) {
                                spin_lock_irqsave(&adapter->stats_lock, flags);
                                e1000_tbi_adjust_stats(hw, &adapter->stats,
                                                       length, skb->data);
                                spin_unlock_irqrestore(&adapter->stats_lock,
                                                       flags);
                                length--;
                        } else {
                                /* recycle */
                                buffer_info->skb = skb;
                                goto next_desc;
                        }
                }

                /* adjust length to remove Ethernet CRC, this must be
                 * done after the TBI_ACCEPT workaround above */
                length -= 4;

                /* probably a little skewed due to removing CRC */
                total_rx_bytes += length;
                total_rx_packets++;

                /* code added for copybreak, this should improve
                 * performance for small packets with large amounts
                 * of reassembly being done in the stack */
                if (length < copybreak) {
                        struct sk_buff *new_skb =
                            netdev_alloc_skb(netdev, length + NET_IP_ALIGN);
                        if (new_skb) {
                                skb_reserve(new_skb, NET_IP_ALIGN);
                                skb_copy_to_linear_data_offset(new_skb,
                                                               -NET_IP_ALIGN,
                                                               (skb->data -
                                                                NET_IP_ALIGN),
                                                               (length +
                                                                NET_IP_ALIGN));
                                /* save the skb in buffer_info as good */
                                buffer_info->skb = skb;
                                skb = new_skb;
                        }
                        /* else just continue with the old one */
                }
                /* end copybreak code */
                skb_put(skb, length);

                /* Receive Checksum Offload */
                e1000_rx_checksum(adapter,
                                  (u32)(status) |
                                  ((u32)(rx_desc->errors) << 24),
                                  le16_to_cpu(rx_desc->csum), skb);

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

                e1000_receive_skb(adapter, status, rx_desc->special, skb);

next_desc:
                rx_desc->status = 0;

                /* return some buffers to hardware, one at a time is too slow */
                if (unlikely(cleaned_count >= E1000_RX_BUFFER_WRITE)) {
                        adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);
                        cleaned_count = 0;
                }

                /* use prefetched values */
                rx_desc = next_rxd;
                buffer_info = next_buffer;
        }
        rx_ring->next_to_clean = i;

        cleaned_count = E1000_DESC_UNUSED(rx_ring);
        if (cleaned_count)
                adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);

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

/**
 * e1000_alloc_jumbo_rx_buffers - Replace used jumbo receive buffers
 * @adapter: address of board private structure
 * @rx_ring: pointer to receive ring structure
 * @cleaned_count: number of buffers to allocate this pass
 **/

static void
e1000_alloc_jumbo_rx_buffers(struct e1000_adapter *adapter,
                             struct e1000_rx_ring *rx_ring, int cleaned_count)
{
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_rx_desc *rx_desc;
        struct e1000_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int bufsz = 256 -
                             16 /*for skb_reserve */ -
                             NET_IP_ALIGN;

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

        while (cleaned_count--) {
                skb = buffer_info->skb;
                if (skb) {
                        skb_trim(skb, 0);
                        goto check_page;
                }

                skb = netdev_alloc_skb(netdev, bufsz);
                if (unlikely(!skb)) {
                        /* Better luck next round */
                        adapter->alloc_rx_buff_failed++;
                        break;
                }

                /* Fix for errata 23, can't cross 64kB boundary */
                if (!e1000_check_64k_bound(adapter, skb->data, bufsz)) {
                        struct sk_buff *oldskb = skb;
                        DPRINTK(PROBE, ERR, "skb align check failed: %u bytes "
                                             "at %p\n", bufsz, skb->data);
                        /* Try again, without freeing the previous */
                        skb = netdev_alloc_skb(netdev, bufsz);
                        /* Failed allocation, critical failure */
                        if (!skb) {
                                dev_kfree_skb(oldskb);
                                adapter->alloc_rx_buff_failed++;
                                break;
                        }

                        if (!e1000_check_64k_bound(adapter, skb->data, bufsz)) {
                                /* give up */
                                dev_kfree_skb(skb);
                                dev_kfree_skb(oldskb);
                                break; /* while (cleaned_count--) */
                        }

                        /* Use new allocation */
                        dev_kfree_skb(oldskb);
                }
                /* 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);

                buffer_info->skb = skb;
                buffer_info->length = adapter->rx_buffer_len;
check_page:
                /* allocate a new page if necessary */
                if (!buffer_info->page) {
                        buffer_info->page = alloc_page(GFP_ATOMIC);
                        if (unlikely(!buffer_info->page)) {
                                adapter->alloc_rx_buff_failed++;
                                break;
                        }
                }

                if (!buffer_info->dma)
                        buffer_info->dma = pci_map_page(pdev,
                                                        buffer_info->page, 0,
                                                        buffer_info->length,
                                                        PCI_DMA_FROMDEVICE);

                rx_desc = E1000_RX_DESC(*rx_ring, i);
                rx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);

                if (unlikely(++i == rx_ring->count))
                        i = 0;
                buffer_info = &rx_ring->buffer_info[i];
        }

        if (likely(rx_ring->next_to_use != i)) {
                rx_ring->next_to_use = i;
                if (unlikely(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->rdt);
        }
}

/**
 * e1000_alloc_rx_buffers - Replace used receive buffers; legacy & extended
 * @adapter: address of board private structure
 **/

static void e1000_alloc_rx_buffers(struct e1000_adapter *adapter,
                                   struct e1000_rx_ring *rx_ring,
                                   int cleaned_count)
{
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_rx_desc *rx_desc;
        struct e1000_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int bufsz = adapter->rx_buffer_len + NET_IP_ALIGN;

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

        while (cleaned_count--) {
                skb = buffer_info->skb;
                if (skb) {
                        skb_trim(skb, 0);
                        goto map_skb;
                }

                skb = netdev_alloc_skb(netdev, bufsz);
                if (unlikely(!skb)) {
                        /* Better luck next round */
                        adapter->alloc_rx_buff_failed++;
                        break;
                }

                /* Fix for errata 23, can't cross 64kB boundary */
                if (!e1000_check_64k_bound(adapter, skb->data, bufsz)) {
                        struct sk_buff *oldskb = skb;
                        DPRINTK(RX_ERR, ERR, "skb align check failed: %u bytes "
                                             "at %p\n", bufsz, skb->data);
                        /* Try again, without freeing the previous */
                        skb = netdev_alloc_skb(netdev, bufsz);
                        /* Failed allocation, critical failure */
                        if (!skb) {
                                dev_kfree_skb(oldskb);
                                adapter->alloc_rx_buff_failed++;
                                break;
                        }

                        if (!e1000_check_64k_bound(adapter, skb->data, bufsz)) {
                                /* give up */
                                dev_kfree_skb(skb);
                                dev_kfree_skb(oldskb);
                                adapter->alloc_rx_buff_failed++;
                                break; /* while !buffer_info->skb */
                        }

                        /* Use new allocation */
                        dev_kfree_skb(oldskb);
                }
                /* 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);

                buffer_info->skb = skb;
                buffer_info->length = adapter->rx_buffer_len;
map_skb:
                buffer_info->dma = pci_map_single(pdev,
                                                  skb->data,
                                                  buffer_info->length,
                                                  PCI_DMA_FROMDEVICE);

                /*
                 * XXX if it was allocated cleanly it will never map to a
                 * boundary crossing
                 */

                /* Fix for errata 23, can't cross 64kB boundary */
                if (!e1000_check_64k_bound(adapter,
                                        (void *)(unsigned long)buffer_info->dma,
                                        adapter->rx_buffer_len)) {
                        DPRINTK(RX_ERR, ERR,
                                "dma align check failed: %u bytes at %p\n",
                                adapter->rx_buffer_len,
                                (void *)(unsigned long)buffer_info->dma);
                        dev_kfree_skb(skb);
                        buffer_info->skb = NULL;

                        pci_unmap_single(pdev, buffer_info->dma,
                                         adapter->rx_buffer_len,
                                         PCI_DMA_FROMDEVICE);
                        buffer_info->dma = 0;

                        adapter->alloc_rx_buff_failed++;
                        break; /* while !buffer_info->skb */
                }
                rx_desc = E1000_RX_DESC(*rx_ring, i);
                rx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);

                if (unlikely(++i == rx_ring->count))
                        i = 0;
                buffer_info = &rx_ring->buffer_info[i];
        }

        if (likely(rx_ring->next_to_use != i)) {
                rx_ring->next_to_use = i;
                if (unlikely(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, hw->hw_addr + rx_ring->rdt);
        }
}

/**
 * e1000_smartspeed - Workaround for SmartSpeed on 82541 and 82547 controllers.
 * @adapter:
 **/

static void e1000_smartspeed(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u16 phy_status;
        u16 phy_ctrl;

        if ((hw->phy_type != e1000_phy_igp) || !hw->autoneg ||
           !(hw->autoneg_advertised & ADVERTISE_1000_FULL))
                return;

        if (adapter->smartspeed == 0) {
                /* If Master/Slave config fault is asserted twice,
                 * we assume back-to-back */
                e1000_read_phy_reg(hw, PHY_1000T_STATUS, &phy_status);
                if (!(phy_status & SR_1000T_MS_CONFIG_FAULT)) return;
                e1000_read_phy_reg(hw, PHY_1000T_STATUS, &phy_status);
                if (!(phy_status & SR_1000T_MS_CONFIG_FAULT)) return;
                e1000_read_phy_reg(hw, PHY_1000T_CTRL, &phy_ctrl);
                if (phy_ctrl & CR_1000T_MS_ENABLE) {
                        phy_ctrl &= ~CR_1000T_MS_ENABLE;
                        e1000_write_phy_reg(hw, PHY_1000T_CTRL,
                                            phy_ctrl);
                        adapter->smartspeed++;
                        if (!e1000_phy_setup_autoneg(hw) &&
                           !e1000_read_phy_reg(hw, PHY_CTRL,
                                               &phy_ctrl)) {
                                phy_ctrl |= (MII_CR_AUTO_NEG_EN |
                                             MII_CR_RESTART_AUTO_NEG);
                                e1000_write_phy_reg(hw, PHY_CTRL,
                                                    phy_ctrl);
                        }
                }
                return;
        } else if (adapter->smartspeed == E1000_SMARTSPEED_DOWNSHIFT) {
                /* If still no link, perhaps using 2/3 pair cable */
                e1000_read_phy_reg(hw, PHY_1000T_CTRL, &phy_ctrl);
                phy_ctrl |= CR_1000T_MS_ENABLE;
                e1000_write_phy_reg(hw, PHY_1000T_CTRL, phy_ctrl);
                if (!e1000_phy_setup_autoneg(hw) &&
                   !e1000_read_phy_reg(hw, PHY_CTRL, &phy_ctrl)) {
                        phy_ctrl |= (MII_CR_AUTO_NEG_EN |
                                     MII_CR_RESTART_AUTO_NEG);
                        e1000_write_phy_reg(hw, PHY_CTRL, phy_ctrl);
                }
        }
        /* Restart process after E1000_SMARTSPEED_MAX iterations */
        if (adapter->smartspeed++ == E1000_SMARTSPEED_MAX)
                adapter->smartspeed = 0;
}

/**
 * e1000_ioctl -
 * @netdev:
 * @ifreq:
 * @cmd:
 **/

static int e1000_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
        switch (cmd) {
        case SIOCGMIIPHY:
        case SIOCGMIIREG:
        case SIOCSMIIREG:
                return e1000_mii_ioctl(netdev, ifr, cmd);
        default:
                return -EOPNOTSUPP;
        }
}

/**
 * e1000_mii_ioctl -
 * @netdev:
 * @ifreq:
 * @cmd:
 **/

static int e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr,
                           int cmd)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        struct mii_ioctl_data *data = if_mii(ifr);
        int retval;
        u16 mii_reg;
        u16 spddplx;
        unsigned long flags;

        if (hw->media_type != e1000_media_type_copper)
                return -EOPNOTSUPP;

        switch (cmd) {
        case SIOCGMIIPHY:
                data->phy_id = hw->phy_addr;
                break;
        case SIOCGMIIREG:
                spin_lock_irqsave(&adapter->stats_lock, flags);
                if (e1000_read_phy_reg(hw, data->reg_num & 0x1F,
                                   &data->val_out)) {
                        spin_unlock_irqrestore(&adapter->stats_lock, flags);
                        return -EIO;
                }
                spin_unlock_irqrestore(&adapter->stats_lock, flags);
                break;
        case SIOCSMIIREG:
                if (data->reg_num & ~(0x1F))
                        return -EFAULT;
                mii_reg = data->val_in;
                spin_lock_irqsave(&adapter->stats_lock, flags);
                if (e1000_write_phy_reg(hw, data->reg_num,
                                        mii_reg)) {
                        spin_unlock_irqrestore(&adapter->stats_lock, flags);
                        return -EIO;
                }
                spin_unlock_irqrestore(&adapter->stats_lock, flags);
                if (hw->media_type == e1000_media_type_copper) {
                        switch (data->reg_num) {
                        case PHY_CTRL:
                                if (mii_reg & MII_CR_POWER_DOWN)
                                        break;
                                if (mii_reg & MII_CR_AUTO_NEG_EN) {
                                        hw->autoneg = 1;
                                        hw->autoneg_advertised = 0x2F;
                                } else {
                                        if (mii_reg & 0x40)
                                                spddplx = SPEED_1000;
                                        else if (mii_reg & 0x2000)
                                                spddplx = SPEED_100;
                                        else
                                                spddplx = SPEED_10;
                                        spddplx += (mii_reg & 0x100)
                                                   ? DUPLEX_FULL :
                                                   DUPLEX_HALF;
                                        retval = e1000_set_spd_dplx(adapter,
                                                                    spddplx);
                                        if (retval)
                                                return retval;
                                }
                                if (netif_running(adapter->netdev))
                                        e1000_reinit_locked(adapter);
                                else
                                        e1000_reset(adapter);
                                break;
                        case M88E1000_PHY_SPEC_CTRL:
                        case M88E1000_EXT_PHY_SPEC_CTRL:
                                if (e1000_phy_reset(hw))
                                        return -EIO;
                                break;
                        }
                } else {
                        switch (data->reg_num) {
                        case PHY_CTRL:
                                if (mii_reg & MII_CR_POWER_DOWN)
                                        break;
                                if (netif_running(adapter->netdev))
                                        e1000_reinit_locked(adapter);
                                else
                                        e1000_reset(adapter);
                                break;
                        }
                }
                break;
        default:
                return -EOPNOTSUPP;
        }
        return E1000_SUCCESS;
}

void e1000_pci_set_mwi(struct e1000_hw *hw)
{
        struct e1000_adapter *adapter = hw->back;
        int ret_val = pci_set_mwi(adapter->pdev);

        if (ret_val)
                DPRINTK(PROBE, ERR, "Error in setting MWI\n");
}

void e1000_pci_clear_mwi(struct e1000_hw *hw)
{
        struct e1000_adapter *adapter = hw->back;

        pci_clear_mwi(adapter->pdev);
}

int e1000_pcix_get_mmrbc(struct e1000_hw *hw)
{
        struct e1000_adapter *adapter = hw->back;
        return pcix_get_mmrbc(adapter->pdev);
}

void e1000_pcix_set_mmrbc(struct e1000_hw *hw, int mmrbc)
{
        struct e1000_adapter *adapter = hw->back;
        pcix_set_mmrbc(adapter->pdev, mmrbc);
}

s32 e1000_read_pcie_cap_reg(struct e1000_hw *hw, u32 reg, u16 *value)
{
    struct e1000_adapter *adapter = hw->back;
    u16 cap_offset;

    cap_offset = pci_find_capability(adapter->pdev, PCI_CAP_ID_EXP);
    if (!cap_offset)
        return -E1000_ERR_CONFIG;

    pci_read_config_word(adapter->pdev, cap_offset + reg, value);

    return E1000_SUCCESS;
}

void e1000_io_write(struct e1000_hw *hw, unsigned long port, u32 value)
{
        outl(value, port);
}

static void e1000_vlan_rx_register(struct net_device *netdev,
                                   struct vlan_group *grp)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 ctrl, rctl;

        if (!test_bit(__E1000_DOWN, &adapter->flags))
                e1000_irq_disable(adapter);
        adapter->vlgrp = grp;

        if (grp) {
                /* enable VLAN tag insert/strip */
                ctrl = er32(CTRL);
                ctrl |= E1000_CTRL_VME;
                ew32(CTRL, ctrl);

                /* enable VLAN receive filtering */
                rctl = er32(RCTL);
                rctl &= ~E1000_RCTL_CFIEN;
                if (!(netdev->flags & IFF_PROMISC))
                        rctl |= E1000_RCTL_VFE;
                ew32(RCTL, rctl);
                e1000_update_mng_vlan(adapter);
        } else {
                /* disable VLAN tag insert/strip */
                ctrl = er32(CTRL);
                ctrl &= ~E1000_CTRL_VME;
                ew32(CTRL, ctrl);

                /* disable VLAN receive filtering */
                rctl = er32(RCTL);
                rctl &= ~E1000_RCTL_VFE;
                ew32(RCTL, rctl);

                if (adapter->mng_vlan_id != (u16)E1000_MNG_VLAN_NONE) {
                        e1000_vlan_rx_kill_vid(netdev,
                                               adapter->mng_vlan_id);
                        adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;
                }
        }

        if (!test_bit(__E1000_DOWN, &adapter->flags))
                e1000_irq_enable(adapter);
}

static void e1000_vlan_rx_add_vid(struct net_device *netdev, u16 vid)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 vfta, index;

        if ((hw->mng_cookie.status &
             E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT) &&
            (vid == adapter->mng_vlan_id))
                return;
        /* add VID to filter table */
        index = (vid >> 5) & 0x7F;
        vfta = E1000_READ_REG_ARRAY(hw, VFTA, index);
        vfta |= (1 << (vid & 0x1F));
        e1000_write_vfta(hw, index, vfta);
}

static void e1000_vlan_rx_kill_vid(struct net_device *netdev, u16 vid)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 vfta, index;

        if (!test_bit(__E1000_DOWN, &adapter->flags))
                e1000_irq_disable(adapter);
        vlan_group_set_device(adapter->vlgrp, vid, NULL);
        if (!test_bit(__E1000_DOWN, &adapter->flags))
                e1000_irq_enable(adapter);

        /* remove VID from filter table */
        index = (vid >> 5) & 0x7F;
        vfta = E1000_READ_REG_ARRAY(hw, VFTA, index);
        vfta &= ~(1 << (vid & 0x1F));
        e1000_write_vfta(hw, index, vfta);
}

static void e1000_restore_vlan(struct e1000_adapter *adapter)
{
        e1000_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;
                        e1000_vlan_rx_add_vid(adapter->netdev, vid);
                }
        }
}

int e1000_set_spd_dplx(struct e1000_adapter *adapter, u16 spddplx)
{
        struct e1000_hw *hw = &adapter->hw;

        hw->autoneg = 0;

        /* Fiber NICs only allow 1000 gbps Full duplex */
        if ((hw->media_type == e1000_media_type_fiber) &&
                spddplx != (SPEED_1000 + DUPLEX_FULL)) {
                DPRINTK(PROBE, ERR, "Unsupported Speed/Duplex configuration\n");
                return -EINVAL;
        }

        switch (spddplx) {
        case SPEED_10 + DUPLEX_HALF:
                hw->forced_speed_duplex = e1000_10_half;
                break;
        case SPEED_10 + DUPLEX_FULL:
                hw->forced_speed_duplex = e1000_10_full;
                break;
        case SPEED_100 + DUPLEX_HALF:
                hw->forced_speed_duplex = e1000_100_half;
                break;
        case SPEED_100 + DUPLEX_FULL:
                hw->forced_speed_duplex = e1000_100_full;
                break;
        case SPEED_1000 + DUPLEX_FULL:
                hw->autoneg = 1;
                hw->autoneg_advertised = ADVERTISE_1000_FULL;
                break;
        case SPEED_1000 + DUPLEX_HALF: /* not supported */
        default:
                DPRINTK(PROBE, ERR, "Unsupported Speed/Duplex configuration\n");
                return -EINVAL;
        }
        return 0;
}

static int __e1000_shutdown(struct pci_dev *pdev, bool *enable_wake)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 ctrl, ctrl_ext, rctl, status;
        u32 wufc = adapter->wol;
#ifdef CONFIG_PM
        int retval = 0;
#endif

        netif_device_detach(netdev);

        if (netif_running(netdev)) {
                WARN_ON(test_bit(__E1000_RESETTING, &adapter->flags));
                e1000_down(adapter);
        }

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

        status = er32(STATUS);
        if (status & E1000_STATUS_LU)
                wufc &= ~E1000_WUFC_LNKC;

        if (wufc) {
                e1000_setup_rctl(adapter);
                e1000_set_rx_mode(netdev);

                /* turn on all-multi mode if wake on multicast is enabled */
                if (wufc & E1000_WUFC_MC) {
                        rctl = er32(RCTL);
                        rctl |= E1000_RCTL_MPE;
                        ew32(RCTL, rctl);
                }

                if (hw->mac_type >= e1000_82540) {
                        ctrl = er32(CTRL);
                        /* advertise wake from D3Cold */
                        #define E1000_CTRL_ADVD3WUC 0x00100000
                        /* phy power management enable */
                        #define E1000_CTRL_EN_PHY_PWR_MGMT 0x00200000
                        ctrl |= E1000_CTRL_ADVD3WUC |
                                E1000_CTRL_EN_PHY_PWR_MGMT;
                        ew32(CTRL, ctrl);
                }

                if (hw->media_type == e1000_media_type_fiber ||
                    hw->media_type == e1000_media_type_internal_serdes) {
                        /* keep the laser running in D3 */
                        ctrl_ext = er32(CTRL_EXT);
                        ctrl_ext |= E1000_CTRL_EXT_SDP7_DATA;
                        ew32(CTRL_EXT, ctrl_ext);
                }

                ew32(WUC, E1000_WUC_PME_EN);
                ew32(WUFC, wufc);
        } else {
                ew32(WUC, 0);
                ew32(WUFC, 0);
        }

        e1000_release_manageability(adapter);

        *enable_wake = !!wufc;

        /* make sure adapter isn't asleep if manageability is enabled */
        if (adapter->en_mng_pt)
                *enable_wake = true;

        if (netif_running(netdev))
                e1000_free_irq(adapter);

        pci_disable_device(pdev);

        return 0;
}

#ifdef CONFIG_PM
static int e1000_suspend(struct pci_dev *pdev, pm_message_t state)
{
        int retval;
        bool wake;

        retval = __e1000_shutdown(pdev, &wake);
        if (retval)
                return retval;

        if (wake) {
                pci_prepare_to_sleep(pdev);
        } else {
                pci_wake_from_d3(pdev, false);
                pci_set_power_state(pdev, PCI_D3hot);
        }

        return 0;
}

static int e1000_resume(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 err;

        pci_set_power_state(pdev, PCI_D0);
        pci_restore_state(pdev);

        if (adapter->need_ioport)
                err = pci_enable_device(pdev);
        else
                err = pci_enable_device_mem(pdev);
        if (err) {
                printk(KERN_ERR "e1000: 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 = e1000_request_irq(adapter);
                if (err)
                        return err;
        }

        e1000_power_up_phy(adapter);
        e1000_reset(adapter);
        ew32(WUS, ~0);

        e1000_init_manageability(adapter);

        if (netif_running(netdev))
                e1000_up(adapter);

        netif_device_attach(netdev);

        return 0;
}
#endif

static void e1000_shutdown(struct pci_dev *pdev)
{
        bool wake;

        __e1000_shutdown(pdev, &wake);

        if (system_state == SYSTEM_POWER_OFF) {
                pci_wake_from_d3(pdev, wake);
                pci_set_power_state(pdev, PCI_D3hot);
        }
}

#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 e1000_netpoll(struct net_device *netdev)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);

        disable_irq(adapter->pdev->irq);
        e1000_intr(adapter->pdev->irq, netdev);
        enable_irq(adapter->pdev->irq);
}
#endif

/**
 * e1000_io_error_detected - called when PCI error is detected
 * @pdev: Pointer to PCI device
 * @state: The current pci conneection state
 *
 * This function is called after a PCI bus error affecting
 * this device has been detected.
 */
static pci_ers_result_t e1000_io_error_detected(struct pci_dev *pdev,
                                                pci_channel_state_t state)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct e1000_adapter *adapter = netdev_priv(netdev);

        netif_device_detach(netdev);

        if (state == pci_channel_io_perm_failure)
                return PCI_ERS_RESULT_DISCONNECT;

        if (netif_running(netdev))
                e1000_down(adapter);
        pci_disable_device(pdev);

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

/**
 * e1000_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. Implementation
 * resembles the first-half of the e1000_resume routine.
 */
static pci_ers_result_t e1000_io_slot_reset(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        int err;

        if (adapter->need_ioport)
                err = pci_enable_device(pdev);
        else
                err = pci_enable_device_mem(pdev);
        if (err) {
                printk(KERN_ERR "e1000: Cannot re-enable PCI device after reset.\n");
                return PCI_ERS_RESULT_DISCONNECT;
        }
        pci_set_master(pdev);

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

        e1000_reset(adapter);
        ew32(WUS, ~0);

        return PCI_ERS_RESULT_RECOVERED;
}

/**
 * e1000_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. Implementation resembles the
 * second-half of the e1000_resume routine.
 */
static void e1000_io_resume(struct pci_dev *pdev)
{
        struct net_device *netdev = pci_get_drvdata(pdev);
        struct e1000_adapter *adapter = netdev_priv(netdev);

        e1000_init_manageability(adapter);

        if (netif_running(netdev)) {
                if (e1000_up(adapter)) {
                        printk("e1000: can't bring device back up after reset\n");
                        return;
                }
        }

        netif_device_attach(netdev);
}

/* e1000_main.c */