/* Intel PRO/1000 Linux driver
 * Copyright(c) 1999 - 2015 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.
 *
 * 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
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/interrupt.h>
#include <linux/tcp.h>
#include <linux/ipv6.h>
#include <linux/slab.h>
#include <net/checksum.h>
#include <net/ip6_checksum.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <linux/pm_qos.h>
#include <linux/pm_runtime.h>
#include <linux/aer.h>
#include <linux/prefetch.h>

#include "e1000.h"

#define DRV_EXTRAVERSION "-k"

#define DRV_VERSION "3.2.6" DRV_EXTRAVERSION
char e1000e_driver_name[] = "e1000e";
const char e1000e_driver_version[] = DRV_VERSION;

#define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV|NETIF_MSG_PROBE|NETIF_MSG_LINK)
static int debug = -1;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

static const struct e1000_info *e1000_info_tbl[] = {
        [board_82571]           = &e1000_82571_info,
        [board_82572]           = &e1000_82572_info,
        [board_82573]           = &e1000_82573_info,
        [board_82574]           = &e1000_82574_info,
        [board_82583]           = &e1000_82583_info,
        [board_80003es2lan]     = &e1000_es2_info,
        [board_ich8lan]         = &e1000_ich8_info,
        [board_ich9lan]         = &e1000_ich9_info,
        [board_ich10lan]        = &e1000_ich10_info,
        [board_pchlan]          = &e1000_pch_info,
        [board_pch2lan]         = &e1000_pch2_info,
        [board_pch_lpt]         = &e1000_pch_lpt_info,
        [board_pch_spt]         = &e1000_pch_spt_info,
};

struct e1000_reg_info {
        u32 ofs;
        char *name;
};

static const struct e1000_reg_info e1000_reg_info_tbl[] = {
        /* General Registers */
        {E1000_CTRL, "CTRL"},
        {E1000_STATUS, "STATUS"},
        {E1000_CTRL_EXT, "CTRL_EXT"},

        /* Interrupt Registers */
        {E1000_ICR, "ICR"},

        /* Rx Registers */
        {E1000_RCTL, "RCTL"},
        {E1000_RDLEN(0), "RDLEN"},
        {E1000_RDH(0), "RDH"},
        {E1000_RDT(0), "RDT"},
        {E1000_RDTR, "RDTR"},
        {E1000_RXDCTL(0), "RXDCTL"},
        {E1000_ERT, "ERT"},
        {E1000_RDBAL(0), "RDBAL"},
        {E1000_RDBAH(0), "RDBAH"},
        {E1000_RDFH, "RDFH"},
        {E1000_RDFT, "RDFT"},
        {E1000_RDFHS, "RDFHS"},
        {E1000_RDFTS, "RDFTS"},
        {E1000_RDFPC, "RDFPC"},

        /* Tx Registers */
        {E1000_TCTL, "TCTL"},
        {E1000_TDBAL(0), "TDBAL"},
        {E1000_TDBAH(0), "TDBAH"},
        {E1000_TDLEN(0), "TDLEN"},
        {E1000_TDH(0), "TDH"},
        {E1000_TDT(0), "TDT"},
        {E1000_TIDV, "TIDV"},
        {E1000_TXDCTL(0), "TXDCTL"},
        {E1000_TADV, "TADV"},
        {E1000_TARC(0), "TARC"},
        {E1000_TDFH, "TDFH"},
        {E1000_TDFT, "TDFT"},
        {E1000_TDFHS, "TDFHS"},
        {E1000_TDFTS, "TDFTS"},
        {E1000_TDFPC, "TDFPC"},

        /* List Terminator */
        {0, NULL}
};

/**
 * __ew32_prepare - prepare to write to MAC CSR register on certain parts
 * @hw: pointer to the HW structure
 *
 * When updating the MAC CSR registers, the Manageability Engine (ME) could
 * be accessing the registers at the same time.  Normally, this is handled in
 * h/w by an arbiter but on some parts there is a bug that acknowledges Host
 * accesses later than it should which could result in the register to have
 * an incorrect value.  Workaround this by checking the FWSM register which
 * has bit 24 set while ME is accessing MAC CSR registers, wait if it is set
 * and try again a number of times.
 **/
s32 __ew32_prepare(struct e1000_hw *hw)
{
        s32 i = E1000_ICH_FWSM_PCIM2PCI_COUNT;

        while ((er32(FWSM) & E1000_ICH_FWSM_PCIM2PCI) && --i)
                udelay(50);

        return i;
}

void __ew32(struct e1000_hw *hw, unsigned long reg, u32 val)
{
        if (hw->adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
                __ew32_prepare(hw);

        writel(val, hw->hw_addr + reg);
}

/**
 * e1000_regdump - register printout routine
 * @hw: pointer to the HW structure
 * @reginfo: pointer to the register info table
 **/
static void e1000_regdump(struct e1000_hw *hw, struct e1000_reg_info *reginfo)
{
        int n = 0;
        char rname[16];
        u32 regs[8];

        switch (reginfo->ofs) {
        case E1000_RXDCTL(0):
                for (n = 0; n < 2; n++)
                        regs[n] = __er32(hw, E1000_RXDCTL(n));
                break;
        case E1000_TXDCTL(0):
                for (n = 0; n < 2; n++)
                        regs[n] = __er32(hw, E1000_TXDCTL(n));
                break;
        case E1000_TARC(0):
                for (n = 0; n < 2; n++)
                        regs[n] = __er32(hw, E1000_TARC(n));
                break;
        default:
                pr_info("%-15s %08x\n",
                        reginfo->name, __er32(hw, reginfo->ofs));
                return;
        }

        snprintf(rname, 16, "%s%s", reginfo->name, "[0-1]");
        pr_info("%-15s %08x %08x\n", rname, regs[0], regs[1]);
}

static void e1000e_dump_ps_pages(struct e1000_adapter *adapter,
                                 struct e1000_buffer *bi)
{
        int i;
        struct e1000_ps_page *ps_page;

        for (i = 0; i < adapter->rx_ps_pages; i++) {
                ps_page = &bi->ps_pages[i];

                if (ps_page->page) {
                        pr_info("packet dump for ps_page %d:\n", i);
                        print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS,
                                       16, 1, page_address(ps_page->page),
                                       PAGE_SIZE, true);
                }
        }
}

/**
 * e1000e_dump - Print registers, Tx-ring and Rx-ring
 * @adapter: board private structure
 **/
static void e1000e_dump(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_reg_info *reginfo;
        struct e1000_ring *tx_ring = adapter->tx_ring;
        struct e1000_tx_desc *tx_desc;
        struct my_u0 {
                __le64 a;
                __le64 b;
        } *u0;
        struct e1000_buffer *buffer_info;
        struct e1000_ring *rx_ring = adapter->rx_ring;
        union e1000_rx_desc_packet_split *rx_desc_ps;
        union e1000_rx_desc_extended *rx_desc;
        struct my_u1 {
                __le64 a;
                __le64 b;
                __le64 c;
                __le64 d;
        } *u1;
        u32 staterr;
        int i = 0;

        if (!netif_msg_hw(adapter))
                return;

        /* Print netdevice Info */
        if (netdev) {
                dev_info(&adapter->pdev->dev, "Net device Info\n");
                pr_info("Device Name     state            trans_start      last_rx\n");
                pr_info("%-15s %016lX %016lX %016lX\n", netdev->name,
                        netdev->state, netdev->trans_start, netdev->last_rx);
        }

        /* Print Registers */
        dev_info(&adapter->pdev->dev, "Register Dump\n");
        pr_info(" Register Name   Value\n");
        for (reginfo = (struct e1000_reg_info *)e1000_reg_info_tbl;
             reginfo->name; reginfo++) {
                e1000_regdump(hw, reginfo);
        }

        /* Print Tx Ring Summary */
        if (!netdev || !netif_running(netdev))
                return;

        dev_info(&adapter->pdev->dev, "Tx Ring Summary\n");
        pr_info("Queue [NTU] [NTC] [bi(ntc)->dma  ] leng ntw timestamp\n");
        buffer_info = &tx_ring->buffer_info[tx_ring->next_to_clean];
        pr_info(" %5d %5X %5X %016llX %04X %3X %016llX\n",
                0, tx_ring->next_to_use, tx_ring->next_to_clean,
                (unsigned long long)buffer_info->dma,
                buffer_info->length,
                buffer_info->next_to_watch,
                (unsigned long long)buffer_info->time_stamp);

        /* Print Tx Ring */
        if (!netif_msg_tx_done(adapter))
                goto rx_ring_summary;

        dev_info(&adapter->pdev->dev, "Tx Ring Dump\n");

        /* Transmit Descriptor Formats - DEXT[29] is 0 (Legacy) or 1 (Extended)
         *
         * Legacy Transmit Descriptor
         *   +--------------------------------------------------------------+
         * 0 |         Buffer Address [63:0] (Reserved on Write Back)       |
         *   +--------------------------------------------------------------+
         * 8 | Special  |    CSS     | Status |  CMD    |  CSO   |  Length  |
         *   +--------------------------------------------------------------+
         *   63       48 47        36 35    32 31     24 23    16 15        0
         *
         * Extended Context Descriptor (DTYP=0x0) for TSO or checksum offload
         *   63      48 47    40 39       32 31             16 15    8 7      0
         *   +----------------------------------------------------------------+
         * 0 |  TUCSE  | TUCS0  |   TUCSS   |     IPCSE       | IPCS0 | IPCSS |
         *   +----------------------------------------------------------------+
         * 8 |   MSS   | HDRLEN | RSV | STA | TUCMD | DTYP |      PAYLEN      |
         *   +----------------------------------------------------------------+
         *   63      48 47    40 39 36 35 32 31   24 23  20 19                0
         *
         * Extended Data Descriptor (DTYP=0x1)
         *   +----------------------------------------------------------------+
         * 0 |                     Buffer Address [63:0]                      |
         *   +----------------------------------------------------------------+
         * 8 | VLAN tag |  POPTS  | Rsvd | Status | Command | DTYP |  DTALEN  |
         *   +----------------------------------------------------------------+
         *   63       48 47     40 39  36 35    32 31     24 23  20 19        0
         */
        pr_info("Tl[desc]     [address 63:0  ] [SpeCssSCmCsLen] [bi->dma       ] leng  ntw timestamp        bi->skb <-- Legacy format\n");
        pr_info("Tc[desc]     [Ce CoCsIpceCoS] [MssHlRSCm0Plen] [bi->dma       ] leng  ntw timestamp        bi->skb <-- Ext Context format\n");
        pr_info("Td[desc]     [address 63:0  ] [VlaPoRSCm1Dlen] [bi->dma       ] leng  ntw timestamp        bi->skb <-- Ext Data format\n");
        for (i = 0; tx_ring->desc && (i < tx_ring->count); i++) {
                const char *next_desc;
                tx_desc = E1000_TX_DESC(*tx_ring, i);
                buffer_info = &tx_ring->buffer_info[i];
                u0 = (struct my_u0 *)tx_desc;
                if (i == tx_ring->next_to_use && i == tx_ring->next_to_clean)
                        next_desc = " NTC/U";
                else if (i == tx_ring->next_to_use)
                        next_desc = " NTU";
                else if (i == tx_ring->next_to_clean)
                        next_desc = " NTC";
                else
                        next_desc = "";
                pr_info("T%c[0x%03X]    %016llX %016llX %016llX %04X  %3X %016llX %p%s\n",
                        (!(le64_to_cpu(u0->b) & (1 << 29)) ? 'l' :
                         ((le64_to_cpu(u0->b) & (1 << 20)) ? 'd' : 'c')),
                        i,
                        (unsigned long long)le64_to_cpu(u0->a),
                        (unsigned long long)le64_to_cpu(u0->b),
                        (unsigned long long)buffer_info->dma,
                        buffer_info->length, buffer_info->next_to_watch,
                        (unsigned long long)buffer_info->time_stamp,
                        buffer_info->skb, next_desc);

                if (netif_msg_pktdata(adapter) && buffer_info->skb)
                        print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS,
                                       16, 1, buffer_info->skb->data,
                                       buffer_info->skb->len, true);
        }

        /* Print Rx Ring Summary */
rx_ring_summary:
        dev_info(&adapter->pdev->dev, "Rx Ring Summary\n");
        pr_info("Queue [NTU] [NTC]\n");
        pr_info(" %5d %5X %5X\n",
                0, rx_ring->next_to_use, rx_ring->next_to_clean);

        /* Print Rx Ring */
        if (!netif_msg_rx_status(adapter))
                return;

        dev_info(&adapter->pdev->dev, "Rx Ring Dump\n");
        switch (adapter->rx_ps_pages) {
        case 1:
        case 2:
        case 3:
                /* [Extended] Packet Split Receive Descriptor Format
                 *
                 *    +-----------------------------------------------------+
                 *  0 |                Buffer Address 0 [63:0]              |
                 *    +-----------------------------------------------------+
                 *  8 |                Buffer Address 1 [63:0]              |
                 *    +-----------------------------------------------------+
                 * 16 |                Buffer Address 2 [63:0]              |
                 *    +-----------------------------------------------------+
                 * 24 |                Buffer Address 3 [63:0]              |
                 *    +-----------------------------------------------------+
                 */
                pr_info("R  [desc]      [buffer 0 63:0 ] [buffer 1 63:0 ] [buffer 2 63:0 ] [buffer 3 63:0 ] [bi->dma       ] [bi->skb] <-- Ext Pkt Split format\n");
                /* [Extended] Receive Descriptor (Write-Back) Format
                 *
                 *   63       48 47    32 31     13 12    8 7    4 3        0
                 *   +------------------------------------------------------+
                 * 0 | Packet   | IP     |  Rsvd   | MRQ   | Rsvd | MRQ RSS |
                 *   | Checksum | Ident  |         | Queue |      |  Type   |
                 *   +------------------------------------------------------+
                 * 8 | VLAN Tag | Length | Extended Error | Extended Status |
                 *   +------------------------------------------------------+
                 *   63       48 47    32 31            20 19               0
                 */
                pr_info("RWB[desc]      [ck ipid mrqhsh] [vl   l0 ee  es] [ l3  l2  l1 hs] [reserved      ] ---------------- [bi->skb] <-- Ext Rx Write-Back format\n");
                for (i = 0; i < rx_ring->count; i++) {
                        const char *next_desc;
                        buffer_info = &rx_ring->buffer_info[i];
                        rx_desc_ps = E1000_RX_DESC_PS(*rx_ring, i);
                        u1 = (struct my_u1 *)rx_desc_ps;
                        staterr =
                            le32_to_cpu(rx_desc_ps->wb.middle.status_error);

                        if (i == rx_ring->next_to_use)
                                next_desc = " NTU";
                        else if (i == rx_ring->next_to_clean)
                                next_desc = " NTC";
                        else
                                next_desc = "";

                        if (staterr & E1000_RXD_STAT_DD) {
                                /* Descriptor Done */
                                pr_info("%s[0x%03X]     %016llX %016llX %016llX %016llX ---------------- %p%s\n",
                                        "RWB", i,
                                        (unsigned long long)le64_to_cpu(u1->a),
                                        (unsigned long long)le64_to_cpu(u1->b),
                                        (unsigned long long)le64_to_cpu(u1->c),
                                        (unsigned long long)le64_to_cpu(u1->d),
                                        buffer_info->skb, next_desc);
                        } else {
                                pr_info("%s[0x%03X]     %016llX %016llX %016llX %016llX %016llX %p%s\n",
                                        "R  ", i,
                                        (unsigned long long)le64_to_cpu(u1->a),
                                        (unsigned long long)le64_to_cpu(u1->b),
                                        (unsigned long long)le64_to_cpu(u1->c),
                                        (unsigned long long)le64_to_cpu(u1->d),
                                        (unsigned long long)buffer_info->dma,
                                        buffer_info->skb, next_desc);

                                if (netif_msg_pktdata(adapter))
                                        e1000e_dump_ps_pages(adapter,
                                                             buffer_info);
                        }
                }
                break;
        default:
        case 0:
                /* Extended Receive Descriptor (Read) Format
                 *
                 *   +-----------------------------------------------------+
                 * 0 |                Buffer Address [63:0]                |
                 *   +-----------------------------------------------------+
                 * 8 |                      Reserved                       |
                 *   +-----------------------------------------------------+
                 */
                pr_info("R  [desc]      [buf addr 63:0 ] [reserved 63:0 ] [bi->dma       ] [bi->skb] <-- Ext (Read) format\n");
                /* Extended Receive Descriptor (Write-Back) Format
                 *
                 *   63       48 47    32 31    24 23            4 3        0
                 *   +------------------------------------------------------+
                 *   |     RSS Hash      |        |               |         |
                 * 0 +-------------------+  Rsvd  |   Reserved    | MRQ RSS |
                 *   | Packet   | IP     |        |               |  Type   |
                 *   | Checksum | Ident  |        |               |         |
                 *   +------------------------------------------------------+
                 * 8 | VLAN Tag | Length | Extended Error | Extended Status |
                 *   +------------------------------------------------------+
                 *   63       48 47    32 31            20 19               0
                 */
                pr_info("RWB[desc]      [cs ipid    mrq] [vt   ln xe  xs] [bi->skb] <-- Ext (Write-Back) format\n");

                for (i = 0; i < rx_ring->count; i++) {
                        const char *next_desc;

                        buffer_info = &rx_ring->buffer_info[i];
                        rx_desc = E1000_RX_DESC_EXT(*rx_ring, i);
                        u1 = (struct my_u1 *)rx_desc;
                        staterr = le32_to_cpu(rx_desc->wb.upper.status_error);

                        if (i == rx_ring->next_to_use)
                                next_desc = " NTU";
                        else if (i == rx_ring->next_to_clean)
                                next_desc = " NTC";
                        else
                                next_desc = "";

                        if (staterr & E1000_RXD_STAT_DD) {
                                /* Descriptor Done */
                                pr_info("%s[0x%03X]     %016llX %016llX ---------------- %p%s\n",
                                        "RWB", i,
                                        (unsigned long long)le64_to_cpu(u1->a),
                                        (unsigned long long)le64_to_cpu(u1->b),
                                        buffer_info->skb, next_desc);
                        } else {
                                pr_info("%s[0x%03X]     %016llX %016llX %016llX %p%s\n",
                                        "R  ", i,
                                        (unsigned long long)le64_to_cpu(u1->a),
                                        (unsigned long long)le64_to_cpu(u1->b),
                                        (unsigned long long)buffer_info->dma,
                                        buffer_info->skb, next_desc);

                                if (netif_msg_pktdata(adapter) &&
                                    buffer_info->skb)
                                        print_hex_dump(KERN_INFO, "",
                                                       DUMP_PREFIX_ADDRESS, 16,
                                                       1,
                                                       buffer_info->skb->data,
                                                       adapter->rx_buffer_len,
                                                       true);
                        }
                }
        }
}

/**
 * e1000_desc_unused - calculate if we have unused descriptors
 **/
static int e1000_desc_unused(struct e1000_ring *ring)
{
        if (ring->next_to_clean > ring->next_to_use)
                return ring->next_to_clean - ring->next_to_use - 1;

        return ring->count + ring->next_to_clean - ring->next_to_use - 1;
}

/**
 * e1000e_systim_to_hwtstamp - convert system time value to hw time stamp
 * @adapter: board private structure
 * @hwtstamps: time stamp structure to update
 * @systim: unsigned 64bit system time value.
 *
 * Convert the system time value stored in the RX/TXSTMP registers into a
 * hwtstamp which can be used by the upper level time stamping functions.
 *
 * The 'systim_lock' spinlock is used to protect the consistency of the
 * system time value. This is needed because reading the 64 bit time
 * value involves reading two 32 bit registers. The first read latches the
 * value.
 **/
static void e1000e_systim_to_hwtstamp(struct e1000_adapter *adapter,
                                      struct skb_shared_hwtstamps *hwtstamps,
                                      u64 systim)
{
        u64 ns;
        unsigned long flags;

        spin_lock_irqsave(&adapter->systim_lock, flags);
        ns = timecounter_cyc2time(&adapter->tc, systim);
        spin_unlock_irqrestore(&adapter->systim_lock, flags);

        memset(hwtstamps, 0, sizeof(*hwtstamps));
        hwtstamps->hwtstamp = ns_to_ktime(ns);
}

/**
 * e1000e_rx_hwtstamp - utility function which checks for Rx time stamp
 * @adapter: board private structure
 * @status: descriptor extended error and status field
 * @skb: particular skb to include time stamp
 *
 * If the time stamp is valid, convert it into the timecounter ns value
 * and store that result into the shhwtstamps structure which is passed
 * up the network stack.
 **/
static void e1000e_rx_hwtstamp(struct e1000_adapter *adapter, u32 status,
                               struct sk_buff *skb)
{
        struct e1000_hw *hw = &adapter->hw;
        u64 rxstmp;

        if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP) ||
            !(status & E1000_RXDEXT_STATERR_TST) ||
            !(er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_VALID))
                return;

        /* The Rx time stamp registers contain the time stamp.  No other
         * received packet will be time stamped until the Rx time stamp
         * registers are read.  Because only one packet can be time stamped
         * at a time, the register values must belong to this packet and
         * therefore none of the other additional attributes need to be
         * compared.
         */
        rxstmp = (u64)er32(RXSTMPL);
        rxstmp |= (u64)er32(RXSTMPH) << 32;
        e1000e_systim_to_hwtstamp(adapter, skb_hwtstamps(skb), rxstmp);

        adapter->flags2 &= ~FLAG2_CHECK_RX_HWTSTAMP;
}

/**
 * e1000_receive_skb - helper function to handle Rx indications
 * @adapter: board private structure
 * @staterr: descriptor extended error and 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,
                              struct net_device *netdev, struct sk_buff *skb,
                              u32 staterr, __le16 vlan)
{
        u16 tag = le16_to_cpu(vlan);

        e1000e_rx_hwtstamp(adapter, staterr, skb);

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

        if (staterr & E1000_RXD_STAT_VP)
                __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tag);

        napi_gro_receive(&adapter->napi, skb);
}

/**
 * e1000_rx_checksum - Receive Checksum Offload
 * @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,
                              struct sk_buff *skb)
{
        u16 status = (u16)status_err;
        u8 errors = (u8)(status_err >> 24);

        skb_checksum_none_assert(skb);

        /* Rx checksum disabled */
        if (!(adapter->netdev->features & NETIF_F_RXCSUM))
                return;

        /* Ignore Checksum bit is set */
        if (status & E1000_RXD_STAT_IXSM)
                return;

        /* TCP/UDP checksum error bit or IP checksum error bit is set */
        if (errors & (E1000_RXD_ERR_TCPE | E1000_RXD_ERR_IPE)) {
                /* let the stack verify checksum errors */
                adapter->hw_csum_err++;
                return;
        }

        /* TCP/UDP Checksum has not been calculated */
        if (!(status & (E1000_RXD_STAT_TCPCS | E1000_RXD_STAT_UDPCS)))
                return;

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

static void e1000e_update_rdt_wa(struct e1000_ring *rx_ring, unsigned int i)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct e1000_hw *hw = &adapter->hw;
        s32 ret_val = __ew32_prepare(hw);

        writel(i, rx_ring->tail);

        if (unlikely(!ret_val && (i != readl(rx_ring->tail)))) {
                u32 rctl = er32(RCTL);

                ew32(RCTL, rctl & ~E1000_RCTL_EN);
                e_err("ME firmware caused invalid RDT - resetting\n");
                schedule_work(&adapter->reset_task);
        }
}

static void e1000e_update_tdt_wa(struct e1000_ring *tx_ring, unsigned int i)
{
        struct e1000_adapter *adapter = tx_ring->adapter;
        struct e1000_hw *hw = &adapter->hw;
        s32 ret_val = __ew32_prepare(hw);

        writel(i, tx_ring->tail);

        if (unlikely(!ret_val && (i != readl(tx_ring->tail)))) {
                u32 tctl = er32(TCTL);

                ew32(TCTL, tctl & ~E1000_TCTL_EN);
                e_err("ME firmware caused invalid TDT - resetting\n");
                schedule_work(&adapter->reset_task);
        }
}

/**
 * e1000_alloc_rx_buffers - Replace used receive buffers
 * @rx_ring: Rx descriptor ring
 **/
static void e1000_alloc_rx_buffers(struct e1000_ring *rx_ring,
                                   int cleaned_count, gfp_t gfp)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        union e1000_rx_desc_extended *rx_desc;
        struct e1000_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int bufsz = adapter->rx_buffer_len;

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

                buffer_info->skb = skb;
map_skb:
                buffer_info->dma = dma_map_single(&pdev->dev, skb->data,
                                                  adapter->rx_buffer_len,
                                                  DMA_FROM_DEVICE);
                if (dma_mapping_error(&pdev->dev, buffer_info->dma)) {
                        dev_err(&pdev->dev, "Rx DMA map failed\n");
                        adapter->rx_dma_failed++;
                        break;
                }

                rx_desc = E1000_RX_DESC_EXT(*rx_ring, i);
                rx_desc->read.buffer_addr = cpu_to_le64(buffer_info->dma);

                if (unlikely(!(i & (E1000_RX_BUFFER_WRITE - 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();
                        if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
                                e1000e_update_rdt_wa(rx_ring, i);
                        else
                                writel(i, rx_ring->tail);
                }
                i++;
                if (i == rx_ring->count)
                        i = 0;
                buffer_info = &rx_ring->buffer_info[i];
        }

        rx_ring->next_to_use = i;
}

/**
 * e1000_alloc_rx_buffers_ps - Replace used receive buffers; packet split
 * @rx_ring: Rx descriptor ring
 **/
static void e1000_alloc_rx_buffers_ps(struct e1000_ring *rx_ring,
                                      int cleaned_count, gfp_t gfp)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        union e1000_rx_desc_packet_split *rx_desc;
        struct e1000_buffer *buffer_info;
        struct e1000_ps_page *ps_page;
        struct sk_buff *skb;
        unsigned int i, j;

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

        while (cleaned_count--) {
                rx_desc = E1000_RX_DESC_PS(*rx_ring, i);

                for (j = 0; j < PS_PAGE_BUFFERS; j++) {
                        ps_page = &buffer_info->ps_pages[j];
                        if (j >= adapter->rx_ps_pages) {
                                /* all unused desc entries get hw null ptr */
                                rx_desc->read.buffer_addr[j + 1] =
                                    ~cpu_to_le64(0);
                                continue;
                        }
                        if (!ps_page->page) {
                                ps_page->page = alloc_page(gfp);
                                if (!ps_page->page) {
                                        adapter->alloc_rx_buff_failed++;
                                        goto no_buffers;
                                }
                                ps_page->dma = dma_map_page(&pdev->dev,
                                                            ps_page->page,
                                                            0, PAGE_SIZE,
                                                            DMA_FROM_DEVICE);
                                if (dma_mapping_error(&pdev->dev,
                                                      ps_page->dma)) {
                                        dev_err(&adapter->pdev->dev,
                                                "Rx DMA page map failed\n");
                                        adapter->rx_dma_failed++;
                                        goto no_buffers;
                                }
                        }
                        /* Refresh the desc even if buffer_addrs
                         * didn't change because each write-back
                         * erases this info.
                         */
                        rx_desc->read.buffer_addr[j + 1] =
                            cpu_to_le64(ps_page->dma);
                }

                skb = __netdev_alloc_skb_ip_align(netdev, adapter->rx_ps_bsize0,
                                                  gfp);

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

                buffer_info->skb = skb;
                buffer_info->dma = dma_map_single(&pdev->dev, skb->data,
                                                  adapter->rx_ps_bsize0,
                                                  DMA_FROM_DEVICE);
                if (dma_mapping_error(&pdev->dev, buffer_info->dma)) {
                        dev_err(&pdev->dev, "Rx DMA map failed\n");
                        adapter->rx_dma_failed++;
                        /* cleanup skb */
                        dev_kfree_skb_any(skb);
                        buffer_info->skb = NULL;
                        break;
                }

                rx_desc->read.buffer_addr[0] = cpu_to_le64(buffer_info->dma);

                if (unlikely(!(i & (E1000_RX_BUFFER_WRITE - 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();
                        if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
                                e1000e_update_rdt_wa(rx_ring, i << 1);
                        else
                                writel(i << 1, rx_ring->tail);
                }

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

no_buffers:
        rx_ring->next_to_use = i;
}

/**
 * e1000_alloc_jumbo_rx_buffers - Replace used jumbo receive buffers
 * @rx_ring: Rx descriptor ring
 * @cleaned_count: number of buffers to allocate this pass
 **/

static void e1000_alloc_jumbo_rx_buffers(struct e1000_ring *rx_ring,
                                         int cleaned_count, gfp_t gfp)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        union e1000_rx_desc_extended *rx_desc;
        struct e1000_buffer *buffer_info;
        struct sk_buff *skb;
        unsigned int i;
        unsigned int bufsz = 256 - 16;  /* for skb_reserve */

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

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

                if (!buffer_info->dma) {
                        buffer_info->dma = dma_map_page(&pdev->dev,
                                                        buffer_info->page, 0,
                                                        PAGE_SIZE,
                                                        DMA_FROM_DEVICE);
                        if (dma_mapping_error(&pdev->dev, buffer_info->dma)) {
                                adapter->alloc_rx_buff_failed++;
                                break;
                        }
                }

                rx_desc = E1000_RX_DESC_EXT(*rx_ring, i);
                rx_desc->read.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();
                if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
                        e1000e_update_rdt_wa(rx_ring, i);
                else
                        writel(i, rx_ring->tail);
        }
}

static inline void e1000_rx_hash(struct net_device *netdev, __le32 rss,
                                 struct sk_buff *skb)
{
        if (netdev->features & NETIF_F_RXHASH)
                skb_set_hash(skb, le32_to_cpu(rss), PKT_HASH_TYPE_L3);
}

/**
 * e1000_clean_rx_irq - Send received data up the network stack
 * @rx_ring: Rx descriptor ring
 *
 * the return value indicates whether actual cleaning was done, there
 * is no guarantee that everything was cleaned
 **/
static bool e1000_clean_rx_irq(struct e1000_ring *rx_ring, int *work_done,
                               int work_to_do)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_hw *hw = &adapter->hw;
        union e1000_rx_desc_extended *rx_desc, *next_rxd;
        struct e1000_buffer *buffer_info, *next_buffer;
        u32 length, staterr;
        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_EXT(*rx_ring, i);
        staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
        buffer_info = &rx_ring->buffer_info[i];

        while (staterr & E1000_RXD_STAT_DD) {
                struct sk_buff *skb;

                if (*work_done >= work_to_do)
                        break;
                (*work_done)++;
                dma_rmb();      /* read descriptor and rx_buffer_info after status DD */

                skb = buffer_info->skb;
                buffer_info->skb = NULL;

                prefetch(skb->data - NET_IP_ALIGN);

                i++;
                if (i == rx_ring->count)
                        i = 0;
                next_rxd = E1000_RX_DESC_EXT(*rx_ring, i);
                prefetch(next_rxd);

                next_buffer = &rx_ring->buffer_info[i];

                cleaned = true;
                cleaned_count++;
                dma_unmap_single(&pdev->dev, buffer_info->dma,
                                 adapter->rx_buffer_len, DMA_FROM_DEVICE);
                buffer_info->dma = 0;

                length = le16_to_cpu(rx_desc->wb.upper.length);

                /* !EOP means multiple descriptors were used to store a single
                 * packet, if that's the case we need to toss it.  In fact, we
                 * need to toss every packet with the EOP bit clear and the
                 * next frame that _does_ have the EOP bit set, as it is by
                 * definition only a frame fragment
                 */
                if (unlikely(!(staterr & E1000_RXD_STAT_EOP)))
                        adapter->flags2 |= FLAG2_IS_DISCARDING;

                if (adapter->flags2 & FLAG2_IS_DISCARDING) {
                        /* All receives must fit into a single buffer */
                        e_dbg("Receive packet consumed multiple buffers\n");
                        /* recycle */
                        buffer_info->skb = skb;
                        if (staterr & E1000_RXD_STAT_EOP)
                                adapter->flags2 &= ~FLAG2_IS_DISCARDING;
                        goto next_desc;
                }

                if (unlikely((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) &&
                             !(netdev->features & NETIF_F_RXALL))) {
                        /* recycle */
                        buffer_info->skb = skb;
                        goto next_desc;
                }

                /* adjust length to remove Ethernet CRC */
                if (!(adapter->flags2 & FLAG2_CRC_STRIPPING)) {

                        /* If configured to store CRC, don't subtract FCS,
                         * but keep the FCS bytes out of the total_rx_bytes
                         * counter
                         */
                        if (netdev->features & NETIF_F_RXFCS)
                                total_rx_bytes -= 4;
                        else
                                length -= 4;
                }

                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 =
                                napi_alloc_skb(&adapter->napi, length);
                        if (new_skb) {
                                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, staterr, skb);

                e1000_rx_hash(netdev, rx_desc->wb.lower.hi_dword.rss, skb);

                e1000_receive_skb(adapter, netdev, skb, staterr,
                                  rx_desc->wb.upper.vlan);

next_desc:
                rx_desc->wb.upper.status_error &= cpu_to_le32(~0xFF);

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

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

                staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
        }
        rx_ring->next_to_clean = i;

        cleaned_count = e1000_desc_unused(rx_ring);
        if (cleaned_count)
                adapter->alloc_rx_buf(rx_ring, cleaned_count, GFP_ATOMIC);

        adapter->total_rx_bytes += total_rx_bytes;
        adapter->total_rx_packets += total_rx_packets;
        return cleaned;
}

static void e1000_put_txbuf(struct e1000_ring *tx_ring,
                            struct e1000_buffer *buffer_info)
{
        struct e1000_adapter *adapter = tx_ring->adapter;

        if (buffer_info->dma) {
                if (buffer_info->mapped_as_page)
                        dma_unmap_page(&adapter->pdev->dev, buffer_info->dma,
                                       buffer_info->length, DMA_TO_DEVICE);
                else
                        dma_unmap_single(&adapter->pdev->dev, buffer_info->dma,
                                         buffer_info->length, DMA_TO_DEVICE);
                buffer_info->dma = 0;
        }
        if (buffer_info->skb) {
                dev_kfree_skb_any(buffer_info->skb);
                buffer_info->skb = NULL;
        }
        buffer_info->time_stamp = 0;
}

static void e1000_print_hw_hang(struct work_struct *work)
{
        struct e1000_adapter *adapter = container_of(work,
                                                     struct e1000_adapter,
                                                     print_hang_task);
        struct net_device *netdev = adapter->netdev;
        struct e1000_ring *tx_ring = adapter->tx_ring;
        unsigned int i = tx_ring->next_to_clean;
        unsigned int eop = tx_ring->buffer_info[i].next_to_watch;
        struct e1000_tx_desc *eop_desc = E1000_TX_DESC(*tx_ring, eop);
        struct e1000_hw *hw = &adapter->hw;
        u16 phy_status, phy_1000t_status, phy_ext_status;
        u16 pci_status;

        if (test_bit(__E1000_DOWN, &adapter->state))
                return;

        if (!adapter->tx_hang_recheck && (adapter->flags2 & FLAG2_DMA_BURST)) {
                /* May be block on write-back, flush and detect again
                 * flush pending descriptor writebacks to memory
                 */
                ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD);
                /* execute the writes immediately */
                e1e_flush();
                /* Due to rare timing issues, write to TIDV again to ensure
                 * the write is successful
                 */
                ew32(TIDV, adapter->tx_int_delay | E1000_TIDV_FPD);
                /* execute the writes immediately */
                e1e_flush();
                adapter->tx_hang_recheck = true;
                return;
        }
        adapter->tx_hang_recheck = false;

        if (er32(TDH(0)) == er32(TDT(0))) {
                e_dbg("false hang detected, ignoring\n");
                return;
        }

        /* Real hang detected */
        netif_stop_queue(netdev);

        e1e_rphy(hw, MII_BMSR, &phy_status);
        e1e_rphy(hw, MII_STAT1000, &phy_1000t_status);
        e1e_rphy(hw, MII_ESTATUS, &phy_ext_status);

        pci_read_config_word(adapter->pdev, PCI_STATUS, &pci_status);

        /* detected Hardware unit hang */
        e_err("Detected Hardware Unit Hang:\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"
              "MAC Status             <%x>\n"
              "PHY Status             <%x>\n"
              "PHY 1000BASE-T Status  <%x>\n"
              "PHY Extended Status    <%x>\n"
              "PCI Status             <%x>\n",
              readl(tx_ring->head), readl(tx_ring->tail), tx_ring->next_to_use,
              tx_ring->next_to_clean, tx_ring->buffer_info[eop].time_stamp,
              eop, jiffies, eop_desc->upper.fields.status, er32(STATUS),
              phy_status, phy_1000t_status, phy_ext_status, pci_status);

        e1000e_dump(adapter);

        /* Suggest workaround for known h/w issue */
        if ((hw->mac.type == e1000_pchlan) && (er32(CTRL) & E1000_CTRL_TFCE))
                e_err("Try turning off Tx pause (flow control) via ethtool\n");
}

/**
 * e1000e_tx_hwtstamp_work - check for Tx time stamp
 * @work: pointer to work struct
 *
 * This work function polls the TSYNCTXCTL valid bit to determine when a
 * timestamp has been taken for the current stored skb.  The timestamp must
 * be for this skb because only one such packet is allowed in the queue.
 */
static void e1000e_tx_hwtstamp_work(struct work_struct *work)
{
        struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
                                                     tx_hwtstamp_work);
        struct e1000_hw *hw = &adapter->hw;

        if (er32(TSYNCTXCTL) & E1000_TSYNCTXCTL_VALID) {
                struct skb_shared_hwtstamps shhwtstamps;
                u64 txstmp;

                txstmp = er32(TXSTMPL);
                txstmp |= (u64)er32(TXSTMPH) << 32;

                e1000e_systim_to_hwtstamp(adapter, &shhwtstamps, txstmp);

                skb_tstamp_tx(adapter->tx_hwtstamp_skb, &shhwtstamps);
                dev_kfree_skb_any(adapter->tx_hwtstamp_skb);
                adapter->tx_hwtstamp_skb = NULL;
        } else if (time_after(jiffies, adapter->tx_hwtstamp_start
                              + adapter->tx_timeout_factor * HZ)) {
                dev_kfree_skb_any(adapter->tx_hwtstamp_skb);
                adapter->tx_hwtstamp_skb = NULL;
                adapter->tx_hwtstamp_timeouts++;
                e_warn("clearing Tx timestamp hang\n");
        } else {
                /* reschedule to check later */
                schedule_work(&adapter->tx_hwtstamp_work);
        }
}

/**
 * e1000_clean_tx_irq - Reclaim resources after transmit completes
 * @tx_ring: Tx descriptor ring
 *
 * the return value indicates whether actual cleaning was done, there
 * is no guarantee that everything was cleaned
 **/
static bool e1000_clean_tx_irq(struct e1000_ring *tx_ring)
{
        struct e1000_adapter *adapter = tx_ring->adapter;
        struct net_device *netdev = adapter->netdev;
        struct e1000_hw *hw = &adapter->hw;
        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;
        unsigned int bytes_compl = 0, pkts_compl = 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;

                dma_rmb();              /* read buffer_info after eop_desc */
                for (; !cleaned; count++) {
                        tx_desc = E1000_TX_DESC(*tx_ring, i);
                        buffer_info = &tx_ring->buffer_info[i];
                        cleaned = (i == eop);

                        if (cleaned) {
                                total_tx_packets += buffer_info->segs;
                                total_tx_bytes += buffer_info->bytecount;
                                if (buffer_info->skb) {
                                        bytes_compl += buffer_info->skb->len;
                                        pkts_compl++;
                                }
                        }

                        e1000_put_txbuf(tx_ring, buffer_info);
                        tx_desc->upper.data = 0;

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

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

        tx_ring->next_to_clean = i;

        netdev_completed_queue(netdev, pkts_compl, bytes_compl);

#define TX_WAKE_THRESHOLD 32
        if (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) &&
                    !(test_bit(__E1000_DOWN, &adapter->state))) {
                        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))
                        schedule_work(&adapter->print_hang_task);
                else
                        adapter->tx_hang_recheck = false;
        }
        adapter->total_tx_bytes += total_tx_bytes;
        adapter->total_tx_packets += total_tx_packets;
        return count < tx_ring->count;
}

/**
 * e1000_clean_rx_irq_ps - Send received data up the network stack; packet split
 * @rx_ring: Rx descriptor ring
 *
 * the return value indicates whether actual cleaning was done, there
 * is no guarantee that everything was cleaned
 **/
static bool e1000_clean_rx_irq_ps(struct e1000_ring *rx_ring, int *work_done,
                                  int work_to_do)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct e1000_hw *hw = &adapter->hw;
        union e1000_rx_desc_packet_split *rx_desc, *next_rxd;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        struct e1000_buffer *buffer_info, *next_buffer;
        struct e1000_ps_page *ps_page;
        struct sk_buff *skb;
        unsigned int i, j;
        u32 length, staterr;
        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_PS(*rx_ring, i);
        staterr = le32_to_cpu(rx_desc->wb.middle.status_error);
        buffer_info = &rx_ring->buffer_info[i];

        while (staterr & E1000_RXD_STAT_DD) {
                if (*work_done >= work_to_do)
                        break;
                (*work_done)++;
                skb = buffer_info->skb;
                dma_rmb();      /* read descriptor and rx_buffer_info after status DD */

                /* in the packet split case this is header only */
                prefetch(skb->data - NET_IP_ALIGN);

                i++;
                if (i == rx_ring->count)
                        i = 0;
                next_rxd = E1000_RX_DESC_PS(*rx_ring, i);
                prefetch(next_rxd);

                next_buffer = &rx_ring->buffer_info[i];

                cleaned = true;
                cleaned_count++;
                dma_unmap_single(&pdev->dev, buffer_info->dma,
                                 adapter->rx_ps_bsize0, DMA_FROM_DEVICE);
                buffer_info->dma = 0;

                /* see !EOP comment in other Rx routine */
                if (!(staterr & E1000_RXD_STAT_EOP))
                        adapter->flags2 |= FLAG2_IS_DISCARDING;

                if (adapter->flags2 & FLAG2_IS_DISCARDING) {
                        e_dbg("Packet Split buffers didn't pick up the full packet\n");
                        dev_kfree_skb_irq(skb);
                        if (staterr & E1000_RXD_STAT_EOP)
                                adapter->flags2 &= ~FLAG2_IS_DISCARDING;
                        goto next_desc;
                }

                if (unlikely((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) &&
                             !(netdev->features & NETIF_F_RXALL))) {
                        dev_kfree_skb_irq(skb);
                        goto next_desc;
                }

                length = le16_to_cpu(rx_desc->wb.middle.length0);

                if (!length) {
                        e_dbg("Last part of the packet spanning multiple descriptors\n");
                        dev_kfree_skb_irq(skb);
                        goto next_desc;
                }

                /* Good Receive */
                skb_put(skb, length);

                {
                        /* this looks ugly, but it seems compiler issues make
                         * it more efficient than reusing j
                         */
                        int l1 = le16_to_cpu(rx_desc->wb.upper.length[0]);

                        /* page alloc/put takes too long and effects small
                         * packet throughput, so unsplit small packets and
                         * save the alloc/put only valid in softirq (napi)
                         * context to call kmap_*
                         */
                        if (l1 && (l1 <= copybreak) &&
                            ((length + l1) <= adapter->rx_ps_bsize0)) {
                                u8 *vaddr;

                                ps_page = &buffer_info->ps_pages[0];

                                /* there is no documentation about how to call
                                 * kmap_atomic, so we can't hold the mapping
                                 * very long
                                 */
                                dma_sync_single_for_cpu(&pdev->dev,
                                                        ps_page->dma,
                                                        PAGE_SIZE,
                                                        DMA_FROM_DEVICE);
                                vaddr = kmap_atomic(ps_page->page);
                                memcpy(skb_tail_pointer(skb), vaddr, l1);
                                kunmap_atomic(vaddr);
                                dma_sync_single_for_device(&pdev->dev,
                                                           ps_page->dma,
                                                           PAGE_SIZE,
                                                           DMA_FROM_DEVICE);

                                /* remove the CRC */
                                if (!(adapter->flags2 & FLAG2_CRC_STRIPPING)) {
                                        if (!(netdev->features & NETIF_F_RXFCS))
                                                l1 -= 4;
                                }

                                skb_put(skb, l1);
                                goto copydone;
                        }       /* if */
                }

                for (j = 0; j < PS_PAGE_BUFFERS; j++) {
                        length = le16_to_cpu(rx_desc->wb.upper.length[j]);
                        if (!length)
                                break;

                        ps_page = &buffer_info->ps_pages[j];
                        dma_unmap_page(&pdev->dev, ps_page->dma, PAGE_SIZE,
                                       DMA_FROM_DEVICE);
                        ps_page->dma = 0;
                        skb_fill_page_desc(skb, j, ps_page->page, 0, length);
                        ps_page->page = NULL;
                        skb->len += length;
                        skb->data_len += length;
                        skb->truesize += PAGE_SIZE;
                }

                /* strip the ethernet crc, problem is we're using pages now so
                 * this whole operation can get a little cpu intensive
                 */
                if (!(adapter->flags2 & FLAG2_CRC_STRIPPING)) {
                        if (!(netdev->features & NETIF_F_RXFCS))
                                pskb_trim(skb, skb->len - 4);
                }

copydone:
                total_rx_bytes += skb->len;
                total_rx_packets++;

                e1000_rx_checksum(adapter, staterr, skb);

                e1000_rx_hash(netdev, rx_desc->wb.lower.hi_dword.rss, skb);

                if (rx_desc->wb.upper.header_status &
                    cpu_to_le16(E1000_RXDPS_HDRSTAT_HDRSP))
                        adapter->rx_hdr_split++;

                e1000_receive_skb(adapter, netdev, skb, staterr,
                                  rx_desc->wb.middle.vlan);

next_desc:
                rx_desc->wb.middle.status_error &= cpu_to_le32(~0xFF);
                buffer_info->skb = NULL;

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

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

                staterr = le32_to_cpu(rx_desc->wb.middle.status_error);
        }
        rx_ring->next_to_clean = i;

        cleaned_count = e1000_desc_unused(rx_ring);
        if (cleaned_count)
                adapter->alloc_rx_buf(rx_ring, cleaned_count, GFP_ATOMIC);

        adapter->total_rx_bytes += total_rx_bytes;
        adapter->total_rx_packets += total_rx_packets;
        return cleaned;
}

/**
 * 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 += PAGE_SIZE;
}

/**
 * e1000_clean_jumbo_rx_irq - Send received data up the network stack; legacy
 * @adapter: board private structure
 *
 * 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_ring *rx_ring, int *work_done,
                                     int work_to_do)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct net_device *netdev = adapter->netdev;
        struct pci_dev *pdev = adapter->pdev;
        union e1000_rx_desc_extended *rx_desc, *next_rxd;
        struct e1000_buffer *buffer_info, *next_buffer;
        u32 length, staterr;
        unsigned int i;
        int cleaned_count = 0;
        bool cleaned = false;
        unsigned int total_rx_bytes = 0, total_rx_packets = 0;
        struct skb_shared_info *shinfo;

        i = rx_ring->next_to_clean;
        rx_desc = E1000_RX_DESC_EXT(*rx_ring, i);
        staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
        buffer_info = &rx_ring->buffer_info[i];

        while (staterr & E1000_RXD_STAT_DD) {
                struct sk_buff *skb;

                if (*work_done >= work_to_do)
                        break;
                (*work_done)++;
                dma_rmb();      /* read descriptor and rx_buffer_info after status DD */

                skb = buffer_info->skb;
                buffer_info->skb = NULL;

                ++i;
                if (i == rx_ring->count)
                        i = 0;
                next_rxd = E1000_RX_DESC_EXT(*rx_ring, i);
                prefetch(next_rxd);

                next_buffer = &rx_ring->buffer_info[i];

                cleaned = true;
                cleaned_count++;
                dma_unmap_page(&pdev->dev, buffer_info->dma, PAGE_SIZE,
                               DMA_FROM_DEVICE);
                buffer_info->dma = 0;

                length = le16_to_cpu(rx_desc->wb.upper.length);

                /* errors is only valid for DD + EOP descriptors */
                if (unlikely((staterr & E1000_RXD_STAT_EOP) &&
                             ((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) &&
                              !(netdev->features & NETIF_F_RXALL)))) {
                        /* 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_irq(rx_ring->rx_skb_top);
                        rx_ring->rx_skb_top = NULL;
                        goto next_desc;
                }
#define rxtop (rx_ring->rx_skb_top)
                if (!(staterr & 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 */
                                shinfo = skb_shinfo(rxtop);
                                skb_fill_page_desc(rxtop, shinfo->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 */
                                shinfo = skb_shinfo(rxtop);
                                skb_fill_page_desc(rxtop, shinfo->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);
                                        memcpy(skb_tail_pointer(skb), vaddr,
                                               length);
                                        kunmap_atomic(vaddr);
                                        /* 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 */
                e1000_rx_checksum(adapter, staterr, skb);

                e1000_rx_hash(netdev, rx_desc->wb.lower.hi_dword.rss, skb);

                /* 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)) {
                        e_err("pskb_may_pull failed.\n");
                        dev_kfree_skb_irq(skb);
                        goto next_desc;
                }

                e1000_receive_skb(adapter, netdev, skb, staterr,
                                  rx_desc->wb.upper.vlan);

next_desc:
                rx_desc->wb.upper.status_error &= cpu_to_le32(~0xFF);

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

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

                staterr = le32_to_cpu(rx_desc->wb.upper.status_error);
        }
        rx_ring->next_to_clean = i;

        cleaned_count = e1000_desc_unused(rx_ring);
        if (cleaned_count)
                adapter->alloc_rx_buf(rx_ring, cleaned_count, GFP_ATOMIC);

        adapter->total_rx_bytes += total_rx_bytes;
        adapter->total_rx_packets += total_rx_packets;
        return cleaned;
}

/**
 * e1000_clean_rx_ring - Free Rx Buffers per Queue
 * @rx_ring: Rx descriptor ring
 **/
static void e1000_clean_rx_ring(struct e1000_ring *rx_ring)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct e1000_buffer *buffer_info;
        struct e1000_ps_page *ps_page;
        struct pci_dev *pdev = adapter->pdev;
        unsigned int i, j;

        /* 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) {
                        if (adapter->clean_rx == e1000_clean_rx_irq)
                                dma_unmap_single(&pdev->dev, buffer_info->dma,
                                                 adapter->rx_buffer_len,
                                                 DMA_FROM_DEVICE);
                        else if (adapter->clean_rx == e1000_clean_jumbo_rx_irq)
                                dma_unmap_page(&pdev->dev, buffer_info->dma,
                                               PAGE_SIZE, DMA_FROM_DEVICE);
                        else if (adapter->clean_rx == e1000_clean_rx_irq_ps)
                                dma_unmap_single(&pdev->dev, buffer_info->dma,
                                                 adapter->rx_ps_bsize0,
                                                 DMA_FROM_DEVICE);
                        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;
                }

                for (j = 0; j < PS_PAGE_BUFFERS; j++) {
                        ps_page = &buffer_info->ps_pages[j];
                        if (!ps_page->page)
                                break;
                        dma_unmap_page(&pdev->dev, ps_page->dma, PAGE_SIZE,
                                       DMA_FROM_DEVICE);
                        ps_page->dma = 0;
                        put_page(ps_page->page);
                        ps_page->page = 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;
        }

        /* 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;
        adapter->flags2 &= ~FLAG2_IS_DISCARDING;
}

static void e1000e_downshift_workaround(struct work_struct *work)
{
        struct e1000_adapter *adapter = container_of(work,
                                                     struct e1000_adapter,
                                                     downshift_task);

        if (test_bit(__E1000_DOWN, &adapter->state))
                return;

        e1000e_gig_downshift_workaround_ich8lan(&adapter->hw);
}

/**
 * e1000_intr_msi - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 **/
static irqreturn_t e1000_intr_msi(int __always_unused 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);

        /* read ICR disables interrupts using IAM */
        if (icr & E1000_ICR_LSC) {
                hw->mac.get_link_status = true;
                /* ICH8 workaround-- Call gig speed drop workaround on cable
                 * disconnect (LSC) before accessing any PHY registers
                 */
                if ((adapter->flags & FLAG_LSC_GIG_SPEED_DROP) &&
                    (!(er32(STATUS) & E1000_STATUS_LU)))
                        schedule_work(&adapter->downshift_task);

                /* 80003ES2LAN workaround-- For packet buffer work-around on
                 * link down event; disable receives here in the ISR and reset
                 * adapter in watchdog
                 */
                if (netif_carrier_ok(netdev) &&
                    adapter->flags & FLAG_RX_NEEDS_RESTART) {
                        /* disable receives */
                        u32 rctl = er32(RCTL);

                        ew32(RCTL, rctl & ~E1000_RCTL_EN);
                        adapter->flags |= FLAG_RESTART_NOW;
                }
                /* guard against interrupt when we're going down */
                if (!test_bit(__E1000_DOWN, &adapter->state))
                        mod_timer(&adapter->watchdog_timer, jiffies + 1);
        }

        /* Reset on uncorrectable ECC error */
        if ((icr & E1000_ICR_ECCER) && ((hw->mac.type == e1000_pch_lpt) ||
                                        (hw->mac.type == e1000_pch_spt))) {
                u32 pbeccsts = er32(PBECCSTS);

                adapter->corr_errors +=
                    pbeccsts & E1000_PBECCSTS_CORR_ERR_CNT_MASK;
                adapter->uncorr_errors +=
                    (pbeccsts & E1000_PBECCSTS_UNCORR_ERR_CNT_MASK) >>
                    E1000_PBECCSTS_UNCORR_ERR_CNT_SHIFT;

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

                /* return immediately since reset is imminent */
                return IRQ_HANDLED;
        }

        if (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);
        }

        return IRQ_HANDLED;
}

/**
 * e1000_intr - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 **/
static irqreturn_t e1000_intr(int __always_unused irq, void *data)
{
        struct net_device *netdev = data;
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 rctl, icr = er32(ICR);

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

        /* IMS will not auto-mask if INT_ASSERTED is not set, and if it is
         * not set, then the adapter didn't send an interrupt
         */
        if (!(icr & E1000_ICR_INT_ASSERTED))
                return IRQ_NONE;

        /* Interrupt Auto-Mask...upon reading ICR,
         * interrupts are masked.  No need for the
         * IMC write
         */

        if (icr & E1000_ICR_LSC) {
                hw->mac.get_link_status = true;
                /* ICH8 workaround-- Call gig speed drop workaround on cable
                 * disconnect (LSC) before accessing any PHY registers
                 */
                if ((adapter->flags & FLAG_LSC_GIG_SPEED_DROP) &&
                    (!(er32(STATUS) & E1000_STATUS_LU)))
                        schedule_work(&adapter->downshift_task);

                /* 80003ES2LAN workaround--
                 * For packet buffer work-around on link down event;
                 * disable receives here in the ISR and
                 * reset adapter in watchdog
                 */
                if (netif_carrier_ok(netdev) &&
                    (adapter->flags & FLAG_RX_NEEDS_RESTART)) {
                        /* disable receives */
                        rctl = er32(RCTL);
                        ew32(RCTL, rctl & ~E1000_RCTL_EN);
                        adapter->flags |= FLAG_RESTART_NOW;
                }
                /* guard against interrupt when we're going down */
                if (!test_bit(__E1000_DOWN, &adapter->state))
                        mod_timer(&adapter->watchdog_timer, jiffies + 1);
        }

        /* Reset on uncorrectable ECC error */
        if ((icr & E1000_ICR_ECCER) && ((hw->mac.type == e1000_pch_lpt) ||
                                        (hw->mac.type == e1000_pch_spt))) {
                u32 pbeccsts = er32(PBECCSTS);

                adapter->corr_errors +=
                    pbeccsts & E1000_PBECCSTS_CORR_ERR_CNT_MASK;
                adapter->uncorr_errors +=
                    (pbeccsts & E1000_PBECCSTS_UNCORR_ERR_CNT_MASK) >>
                    E1000_PBECCSTS_UNCORR_ERR_CNT_SHIFT;

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

                /* return immediately since reset is imminent */
                return IRQ_HANDLED;
        }

        if (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);
        }

        return IRQ_HANDLED;
}

static irqreturn_t e1000_msix_other(int __always_unused 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 (!(icr & E1000_ICR_INT_ASSERTED)) {
                if (!test_bit(__E1000_DOWN, &adapter->state))
                        ew32(IMS, E1000_IMS_OTHER);
                return IRQ_NONE;
        }

        if (icr & adapter->eiac_mask)
                ew32(ICS, (icr & adapter->eiac_mask));

        if (icr & E1000_ICR_OTHER) {
                if (!(icr & E1000_ICR_LSC))
                        goto no_link_interrupt;
                hw->mac.get_link_status = true;
                /* guard against interrupt when we're going down */
                if (!test_bit(__E1000_DOWN, &adapter->state))
                        mod_timer(&adapter->watchdog_timer, jiffies + 1);
        }

no_link_interrupt:
        if (!test_bit(__E1000_DOWN, &adapter->state))
                ew32(IMS, E1000_IMS_LSC | E1000_IMS_OTHER);

        return IRQ_HANDLED;
}

static irqreturn_t e1000_intr_msix_tx(int __always_unused irq, void *data)
{
        struct net_device *netdev = data;
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_ring *tx_ring = adapter->tx_ring;

        adapter->total_tx_bytes = 0;
        adapter->total_tx_packets = 0;

        if (!e1000_clean_tx_irq(tx_ring))
                /* Ring was not completely cleaned, so fire another interrupt */
                ew32(ICS, tx_ring->ims_val);

        return IRQ_HANDLED;
}

static irqreturn_t e1000_intr_msix_rx(int __always_unused irq, void *data)
{
        struct net_device *netdev = data;
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_ring *rx_ring = adapter->rx_ring;

        /* Write the ITR value calculated at the end of the
         * previous interrupt.
         */
        if (rx_ring->set_itr) {
                writel(1000000000 / (rx_ring->itr_val * 256),
                       rx_ring->itr_register);
                rx_ring->set_itr = 0;
        }

        if (napi_schedule_prep(&adapter->napi)) {
                adapter->total_rx_bytes = 0;
                adapter->total_rx_packets = 0;
                __napi_schedule(&adapter->napi);
        }
        return IRQ_HANDLED;
}

/**
 * e1000_configure_msix - Configure MSI-X hardware
 *
 * e1000_configure_msix sets up the hardware to properly
 * generate MSI-X interrupts.
 **/
static void e1000_configure_msix(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_ring *rx_ring = adapter->rx_ring;
        struct e1000_ring *tx_ring = adapter->tx_ring;
        int vector = 0;
        u32 ctrl_ext, ivar = 0;

        adapter->eiac_mask = 0;

        /* Workaround issue with spurious interrupts on 82574 in MSI-X mode */
        if (hw->mac.type == e1000_82574) {
                u32 rfctl = er32(RFCTL);

                rfctl |= E1000_RFCTL_ACK_DIS;
                ew32(RFCTL, rfctl);
        }

        /* Configure Rx vector */
        rx_ring->ims_val = E1000_IMS_RXQ0;

        adapter->eiac_mask |= rx_ring->ims_val;
        if (rx_ring->itr_val)
                writel(1000000000 / (rx_ring->itr_val * 256),
                       rx_ring->itr_register);
        else
                writel(1, rx_ring->itr_register);
        ivar = E1000_IVAR_INT_ALLOC_VALID | vector;

        /* Configure Tx vector */
        tx_ring->ims_val = E1000_IMS_TXQ0;
        vector++;
        if (tx_ring->itr_val)
                writel(1000000000 / (tx_ring->itr_val * 256),
                       tx_ring->itr_register);
        else
                writel(1, tx_ring->itr_register);
        adapter->eiac_mask |= tx_ring->ims_val;
        ivar |= ((E1000_IVAR_INT_ALLOC_VALID | vector) << 8);

        /* set vector for Other Causes, e.g. link changes */
        vector++;
        ivar |= ((E1000_IVAR_INT_ALLOC_VALID | vector) << 16);
        if (rx_ring->itr_val)
                writel(1000000000 / (rx_ring->itr_val * 256),
                       hw->hw_addr + E1000_EITR_82574(vector));
        else
                writel(1, hw->hw_addr + E1000_EITR_82574(vector));

        /* Cause Tx interrupts on every write back */
        ivar |= (1 << 31);

        ew32(IVAR, ivar);

        /* enable MSI-X PBA support */
        ctrl_ext = er32(CTRL_EXT);
        ctrl_ext |= E1000_CTRL_EXT_PBA_CLR;

        /* Auto-Mask Other interrupts upon ICR read */
        ew32(IAM, ~E1000_EIAC_MASK_82574 | E1000_IMS_OTHER);
        ctrl_ext |= E1000_CTRL_EXT_EIAME;
        ew32(CTRL_EXT, ctrl_ext);
        e1e_flush();
}

void e1000e_reset_interrupt_capability(struct e1000_adapter *adapter)
{
        if (adapter->msix_entries) {
                pci_disable_msix(adapter->pdev);
                kfree(adapter->msix_entries);
                adapter->msix_entries = NULL;
        } else if (adapter->flags & FLAG_MSI_ENABLED) {
                pci_disable_msi(adapter->pdev);
                adapter->flags &= ~FLAG_MSI_ENABLED;
        }
}

/**
 * e1000e_set_interrupt_capability - set MSI or MSI-X if supported
 *
 * Attempt to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 **/
void e1000e_set_interrupt_capability(struct e1000_adapter *adapter)
{
        int err;
        int i;

        switch (adapter->int_mode) {
        case E1000E_INT_MODE_MSIX:
                if (adapter->flags & FLAG_HAS_MSIX) {
                        adapter->num_vectors = 3; /* RxQ0, TxQ0 and other */
                        adapter->msix_entries = kcalloc(adapter->num_vectors,
                                                        sizeof(struct
                                                               msix_entry),
                                                        GFP_KERNEL);
                        if (adapter->msix_entries) {
                                struct e1000_adapter *a = adapter;

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

                                err = pci_enable_msix_range(a->pdev,
                                                            a->msix_entries,
                                                            a->num_vectors,
                                                            a->num_vectors);
                                if (err > 0)
                                        return;
                        }
                        /* MSI-X failed, so fall through and try MSI */
                        e_err("Failed to initialize MSI-X interrupts.  Falling back to MSI interrupts.\n");
                        e1000e_reset_interrupt_capability(adapter);
                }
                adapter->int_mode = E1000E_INT_MODE_MSI;
                /* Fall through */
        case E1000E_INT_MODE_MSI:
                if (!pci_enable_msi(adapter->pdev)) {
                        adapter->flags |= FLAG_MSI_ENABLED;
                } else {
                        adapter->int_mode = E1000E_INT_MODE_LEGACY;
                        e_err("Failed to initialize MSI interrupts.  Falling back to legacy interrupts.\n");
                }
                /* Fall through */
        case E1000E_INT_MODE_LEGACY:
                /* Don't do anything; this is the system default */
                break;
        }

        /* store the number of vectors being used */
        adapter->num_vectors = 1;
}

/**
 * e1000_request_msix - Initialize MSI-X interrupts
 *
 * e1000_request_msix allocates MSI-X vectors and requests interrupts from the
 * kernel.
 **/
static int e1000_request_msix(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int err = 0, vector = 0;

        if (strlen(netdev->name) < (IFNAMSIZ - 5))
                snprintf(adapter->rx_ring->name,
                         sizeof(adapter->rx_ring->name) - 1,
                         "%s-rx-0", netdev->name);
        else
                memcpy(adapter->rx_ring->name, netdev->name, IFNAMSIZ);
        err = request_irq(adapter->msix_entries[vector].vector,
                          e1000_intr_msix_rx, 0, adapter->rx_ring->name,
                          netdev);
        if (err)
                return err;
        adapter->rx_ring->itr_register = adapter->hw.hw_addr +
            E1000_EITR_82574(vector);
        adapter->rx_ring->itr_val = adapter->itr;
        vector++;

        if (strlen(netdev->name) < (IFNAMSIZ - 5))
                snprintf(adapter->tx_ring->name,
                         sizeof(adapter->tx_ring->name) - 1,
                         "%s-tx-0", netdev->name);
        else
                memcpy(adapter->tx_ring->name, netdev->name, IFNAMSIZ);
        err = request_irq(adapter->msix_entries[vector].vector,
                          e1000_intr_msix_tx, 0, adapter->tx_ring->name,
                          netdev);
        if (err)
                return err;
        adapter->tx_ring->itr_register = adapter->hw.hw_addr +
            E1000_EITR_82574(vector);
        adapter->tx_ring->itr_val = adapter->itr;
        vector++;

        err = request_irq(adapter->msix_entries[vector].vector,
                          e1000_msix_other, 0, netdev->name, netdev);
        if (err)
                return err;

        e1000_configure_msix(adapter);

        return 0;
}

/**
 * e1000_request_irq - initialize interrupts
 *
 * Attempts to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 **/
static int e1000_request_irq(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        int err;

        if (adapter->msix_entries) {
                err = e1000_request_msix(adapter);
                if (!err)
                        return err;
                /* fall back to MSI */
                e1000e_reset_interrupt_capability(adapter);
                adapter->int_mode = E1000E_INT_MODE_MSI;
                e1000e_set_interrupt_capability(adapter);
        }
        if (adapter->flags & FLAG_MSI_ENABLED) {
                err = request_irq(adapter->pdev->irq, e1000_intr_msi, 0,
                                  netdev->name, netdev);
                if (!err)
                        return err;

                /* fall back to legacy interrupt */
                e1000e_reset_interrupt_capability(adapter);
                adapter->int_mode = E1000E_INT_MODE_LEGACY;
        }

        err = request_irq(adapter->pdev->irq, e1000_intr, IRQF_SHARED,
                          netdev->name, netdev);
        if (err)
                e_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;

        if (adapter->msix_entries) {
                int vector = 0;

                free_irq(adapter->msix_entries[vector].vector, netdev);
                vector++;

                free_irq(adapter->msix_entries[vector].vector, netdev);
                vector++;

                /* Other Causes interrupt vector */
                free_irq(adapter->msix_entries[vector].vector, netdev);
                return;
        }

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

/**
 * e1000_irq_disable - Mask off interrupt generation on the NIC
 **/
static void e1000_irq_disable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        ew32(IMC, ~0);
        if (adapter->msix_entries)
                ew32(EIAC_82574, 0);
        e1e_flush();

        if (adapter->msix_entries) {
                int i;

                for (i = 0; i < adapter->num_vectors; i++)
                        synchronize_irq(adapter->msix_entries[i].vector);
        } else {
                synchronize_irq(adapter->pdev->irq);
        }
}

/**
 * e1000_irq_enable - Enable default interrupt generation settings
 **/
static void e1000_irq_enable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;

        if (adapter->msix_entries) {
                ew32(EIAC_82574, adapter->eiac_mask & E1000_EIAC_MASK_82574);
                ew32(IMS, adapter->eiac_mask | E1000_IMS_OTHER | E1000_IMS_LSC);
        } else if ((hw->mac.type == e1000_pch_lpt) ||
                   (hw->mac.type == e1000_pch_spt)) {
                ew32(IMS, IMS_ENABLE_MASK | E1000_IMS_ECCER);
        } else {
                ew32(IMS, IMS_ENABLE_MASK);
        }
        e1e_flush();
}

/**
 * e1000e_get_hw_control - get control of the h/w from f/w
 * @adapter: address of board private structure
 *
 * e1000e_get_hw_control sets {CTRL_EXT|SWSM}:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that
 * the driver is loaded. For AMT version (only with 82573)
 * of the f/w this means that the network i/f is open.
 **/
void e1000e_get_hw_control(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 ctrl_ext;
        u32 swsm;

        /* Let firmware know the driver has taken over */
        if (adapter->flags & FLAG_HAS_SWSM_ON_LOAD) {
                swsm = er32(SWSM);
                ew32(SWSM, swsm | E1000_SWSM_DRV_LOAD);
        } else if (adapter->flags & FLAG_HAS_CTRLEXT_ON_LOAD) {
                ctrl_ext = er32(CTRL_EXT);
                ew32(CTRL_EXT, ctrl_ext | E1000_CTRL_EXT_DRV_LOAD);
        }
}

/**
 * e1000e_release_hw_control - release control of the h/w to f/w
 * @adapter: address of board private structure
 *
 * e1000e_release_hw_control resets {CTRL_EXT|SWSM}:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that the
 * driver is no longer loaded. For AMT version (only with 82573) i
 * of the f/w this means that the network i/f is closed.
 *
 **/
void e1000e_release_hw_control(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 ctrl_ext;
        u32 swsm;

        /* Let firmware taken over control of h/w */
        if (adapter->flags & FLAG_HAS_SWSM_ON_LOAD) {
                swsm = er32(SWSM);
                ew32(SWSM, swsm & ~E1000_SWSM_DRV_LOAD);
        } else if (adapter->flags & FLAG_HAS_CTRLEXT_ON_LOAD) {
                ctrl_ext = er32(CTRL_EXT);
                ew32(CTRL_EXT, ctrl_ext & ~E1000_CTRL_EXT_DRV_LOAD);
        }
}

/**
 * e1000_alloc_ring_dma - allocate memory for a ring structure
 **/
static int e1000_alloc_ring_dma(struct e1000_adapter *adapter,
                                struct e1000_ring *ring)
{
        struct pci_dev *pdev = adapter->pdev;

        ring->desc = dma_alloc_coherent(&pdev->dev, ring->size, &ring->dma,
                                        GFP_KERNEL);
        if (!ring->desc)
                return -ENOMEM;

        return 0;
}

/**
 * e1000e_setup_tx_resources - allocate Tx resources (Descriptors)
 * @tx_ring: Tx descriptor ring
 *
 * Return 0 on success, negative on failure
 **/
int e1000e_setup_tx_resources(struct e1000_ring *tx_ring)
{
        struct e1000_adapter *adapter = tx_ring->adapter;
        int err = -ENOMEM, size;

        size = sizeof(struct e1000_buffer) * tx_ring->count;
        tx_ring->buffer_info = vzalloc(size);
        if (!tx_ring->buffer_info)
                goto err;

        /* round up to nearest 4K */
        tx_ring->size = tx_ring->count * sizeof(struct e1000_tx_desc);
        tx_ring->size = ALIGN(tx_ring->size, 4096);

        err = e1000_alloc_ring_dma(adapter, tx_ring);
        if (err)
                goto err;

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

        return 0;
err:
        vfree(tx_ring->buffer_info);
        e_err("Unable to allocate memory for the transmit descriptor ring\n");
        return err;
}

/**
 * e1000e_setup_rx_resources - allocate Rx resources (Descriptors)
 * @rx_ring: Rx descriptor ring
 *
 * Returns 0 on success, negative on failure
 **/
int e1000e_setup_rx_resources(struct e1000_ring *rx_ring)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct e1000_buffer *buffer_info;
        int i, size, desc_len, err = -ENOMEM;

        size = sizeof(struct e1000_buffer) * rx_ring->count;
        rx_ring->buffer_info = vzalloc(size);
        if (!rx_ring->buffer_info)
                goto err;

        for (i = 0; i < rx_ring->count; i++) {
                buffer_info = &rx_ring->buffer_info[i];
                buffer_info->ps_pages = kcalloc(PS_PAGE_BUFFERS,
                                                sizeof(struct e1000_ps_page),
                                                GFP_KERNEL);
                if (!buffer_info->ps_pages)
                        goto err_pages;
        }

        desc_len = sizeof(union e1000_rx_desc_packet_split);

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

        err = e1000_alloc_ring_dma(adapter, rx_ring);
        if (err)
                goto err_pages;

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

        return 0;

err_pages:
        for (i = 0; i < rx_ring->count; i++) {
                buffer_info = &rx_ring->buffer_info[i];
                kfree(buffer_info->ps_pages);
        }
err:
        vfree(rx_ring->buffer_info);
        e_err("Unable to allocate memory for the receive descriptor ring\n");
        return err;
}

/**
 * e1000_clean_tx_ring - Free Tx Buffers
 * @tx_ring: Tx descriptor ring
 **/
static void e1000_clean_tx_ring(struct e1000_ring *tx_ring)
{
        struct e1000_adapter *adapter = tx_ring->adapter;
        struct e1000_buffer *buffer_info;
        unsigned long size;
        unsigned int i;

        for (i = 0; i < tx_ring->count; i++) {
                buffer_info = &tx_ring->buffer_info[i];
                e1000_put_txbuf(tx_ring, buffer_info);
        }

        netdev_reset_queue(adapter->netdev);
        size = sizeof(struct e1000_buffer) * tx_ring->count;
        memset(tx_ring->buffer_info, 0, size);

        memset(tx_ring->desc, 0, tx_ring->size);

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

/**
 * e1000e_free_tx_resources - Free Tx Resources per Queue
 * @tx_ring: Tx descriptor ring
 *
 * Free all transmit software resources
 **/
void e1000e_free_tx_resources(struct e1000_ring *tx_ring)
{
        struct e1000_adapter *adapter = tx_ring->adapter;
        struct pci_dev *pdev = adapter->pdev;

        e1000_clean_tx_ring(tx_ring);

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

        dma_free_coherent(&pdev->dev, tx_ring->size, tx_ring->desc,
                          tx_ring->dma);
        tx_ring->desc = NULL;
}

/**
 * e1000e_free_rx_resources - Free Rx Resources
 * @rx_ring: Rx descriptor ring
 *
 * Free all receive software resources
 **/
void e1000e_free_rx_resources(struct e1000_ring *rx_ring)
{
        struct e1000_adapter *adapter = rx_ring->adapter;
        struct pci_dev *pdev = adapter->pdev;
        int i;

        e1000_clean_rx_ring(rx_ring);

        for (i = 0; i < rx_ring->count; i++)
                kfree(rx_ring->buffer_info[i].ps_pages);

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

        dma_free_coherent(&pdev->dev, rx_ring->size, rx_ring->desc,
                          rx_ring->dma);
        rx_ring->desc = NULL;
}

/**
 * e1000_update_itr - update the dynamic ITR value based on statistics
 * @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
 *
 *      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.
 **/
static unsigned int e1000_update_itr(u16 itr_setting, int packets, int bytes)
{
        unsigned int retval = itr_setting;

        if (packets == 0)
                return itr_setting;

        switch (itr_setting) {
        case lowest_latency:
                /* handle TSO and jumbo frames */
                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) {
                        /* this if handles the TSO accounting */
                        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;
        }

        return retval;
}

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

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

        if (adapter->flags2 & FLAG2_DISABLE_AIM) {
                new_itr = 0;
                goto set_itr_now;
        }

        adapter->tx_itr = e1000_update_itr(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->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);

        /* counts and packets in update_itr are dependent on these numbers */
        switch (current_itr) {
        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;
                adapter->rx_ring->itr_val = new_itr;
                if (adapter->msix_entries)
                        adapter->rx_ring->set_itr = 1;
                else
                        e1000e_write_itr(adapter, new_itr);
        }
}

/**
 * e1000e_write_itr - write the ITR value to the appropriate registers
 * @adapter: address of board private structure
 * @itr: new ITR value to program
 *
 * e1000e_write_itr determines if the adapter is in MSI-X mode
 * and, if so, writes the EITR registers with the ITR value.
 * Otherwise, it writes the ITR value into the ITR register.
 **/
void e1000e_write_itr(struct e1000_adapter *adapter, u32 itr)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 new_itr = itr ? 1000000000 / (itr * 256) : 0;

        if (adapter->msix_entries) {
                int vector;

                for (vector = 0; vector < adapter->num_vectors; vector++)
                        writel(new_itr, hw->hw_addr + E1000_EITR_82574(vector));
        } else {
                ew32(ITR, new_itr);
        }
}

/**
 * e1000_alloc_queues - Allocate memory for all rings
 * @adapter: board private structure to initialize
 **/
static int e1000_alloc_queues(struct e1000_adapter *adapter)
{
        int size = sizeof(struct e1000_ring);

        adapter->tx_ring = kzalloc(size, GFP_KERNEL);
        if (!adapter->tx_ring)
                goto err;
        adapter->tx_ring->count = adapter->tx_ring_count;
        adapter->tx_ring->adapter = adapter;

        adapter->rx_ring = kzalloc(size, GFP_KERNEL);
        if (!adapter->rx_ring)
                goto err;
        adapter->rx_ring->count = adapter->rx_ring_count;
        adapter->rx_ring->adapter = adapter;

        return 0;
err:
        e_err("Unable to allocate memory for queues\n");
        kfree(adapter->rx_ring);
        kfree(adapter->tx_ring);
        return -ENOMEM;
}

/**
 * e1000e_poll - NAPI Rx polling callback
 * @napi: struct associated with this polling callback
 * @weight: number of packets driver is allowed to process this poll
 **/
static int e1000e_poll(struct napi_struct *napi, int weight)
{
        struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter,
                                                     napi);
        struct e1000_hw *hw = &adapter->hw;
        struct net_device *poll_dev = adapter->netdev;
        int tx_cleaned = 1, work_done = 0;

        adapter = netdev_priv(poll_dev);

        if (!adapter->msix_entries ||
            (adapter->rx_ring->ims_val & adapter->tx_ring->ims_val))
                tx_cleaned = e1000_clean_tx_irq(adapter->tx_ring);

        adapter->clean_rx(adapter->rx_ring, &work_done, weight);

        if (!tx_cleaned)
                work_done = weight;

        /* If weight not fully consumed, exit the polling mode */
        if (work_done < weight) {
                if (adapter->itr_setting & 3)
                        e1000_set_itr(adapter);
                napi_complete(napi);
                if (!test_bit(__E1000_DOWN, &adapter->state)) {
                        if (adapter->msix_entries)
                                ew32(IMS, adapter->rx_ring->ims_val);
                        else
                                e1000_irq_enable(adapter);
                }
        }

        return work_done;
}

static int e1000_vlan_rx_add_vid(struct net_device *netdev,
                                 __always_unused __be16 proto, u16 vid)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 vfta, index;

        /* don't update vlan cookie if already programmed */
        if ((adapter->hw.mng_cookie.status &
             E1000_MNG_DHCP_COOKIE_STATUS_VLAN) &&
            (vid == adapter->mng_vlan_id))
                return 0;

        /* add VID to filter table */
        if (adapter->flags & FLAG_HAS_HW_VLAN_FILTER) {
                index = (vid >> 5) & 0x7F;
                vfta = E1000_READ_REG_ARRAY(hw, E1000_VFTA, index);
                vfta |= (1 << (vid & 0x1F));
                hw->mac.ops.write_vfta(hw, index, vfta);
        }

        set_bit(vid, adapter->active_vlans);

        return 0;
}

static int e1000_vlan_rx_kill_vid(struct net_device *netdev,
                                  __always_unused __be16 proto, u16 vid)
{
        struct e1000_adapter *adapter = netdev_priv(netdev);
        struct e1000_hw *hw = &adapter->hw;
        u32 vfta, index;

        if ((adapter->hw.mng_cookie.status &
             E1000_MNG_DHCP_COOKIE_STATUS_VLAN) &&
            (vid == adapter->mng_vlan_id)) {
                /* release control to f/w */
                e1000e_release_hw_control(adapter);
                return 0;
        }

        /* remove VID from filter table */
        if (adapter->flags & FLAG_HAS_HW_VLAN_FILTER) {
                index = (vid >> 5) & 0x7F;
                vfta = E1000_READ_REG_ARRAY(hw, E1000_VFTA, index);
                vfta &= ~(1 << (vid & 0x1F));
                hw->mac.ops.write_vfta(hw, index, vfta);
        }

        clear_bit(vid, adapter->active_vlans);

        return 0;
}

/**
 * e1000e_vlan_filter_disable - helper to disable hw VLAN filtering
 * @adapter: board private structure to initialize
 **/
static void e1000e_vlan_filter_disable(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        struct e1000_hw *hw = &adapter->hw;
        u32 rctl;

        if (adapter->flags & FLAG_HAS_HW_VLAN_FILTER) {
                /* disable VLAN receive filtering */
                rctl = er32(RCTL);
                rctl &= ~(E1000_RCTL_VFE | E1000_RCTL_CFIEN);
                ew32(RCTL, rctl);

                if (adapter->mng_vlan_id != (u16)E1000_MNG_VLAN_NONE) {
                        e1000_vlan_rx_kill_vid(netdev, htons(ETH_P_8021Q),
                                               adapter->mng_vlan_id);
                        adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;
                }
        }
}

/**
 * e1000e_vlan_filter_enable - helper to enable HW VLAN filtering
 * @adapter: board private structure to initialize
 **/
static void e1000e_vlan_filter_enable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 rctl;

        if (adapter->flags & FLAG_HAS_HW_VLAN_FILTER) {
                /* enable VLAN receive filtering */
                rctl = er32(RCTL);
                rctl |= E1000_RCTL_VFE;
                rctl &= ~E1000_RCTL_CFIEN;
                ew32(RCTL, rctl);
        }
}

/**
 * e1000e_vlan_strip_enable - helper to disable HW VLAN stripping
 * @adapter: board private structure to initialize
 **/
static void e1000e_vlan_strip_disable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 ctrl;

        /* disable VLAN tag insert/strip */
        ctrl = er32(CTRL);
        ctrl &= ~E1000_CTRL_VME;
        ew32(CTRL, ctrl);
}

/**
 * e1000e_vlan_strip_enable - helper to enable HW VLAN stripping
 * @adapter: board private structure to initialize
 **/
static void e1000e_vlan_strip_enable(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 ctrl;

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

static void e1000_update_mng_vlan(struct e1000_adapter *adapter)
{
        struct net_device *netdev = adapter->netdev;
        u16 vid = adapter->hw.mng_cookie.vlan_id;
        u16 old_vid = adapter->mng_vlan_id;

        if (adapter->hw.mng_cookie.status & E1000_MNG_DHCP_COOKIE_STATUS_VLAN) {
                e1000_vlan_rx_add_vid(netdev, htons(ETH_P_8021Q), vid);
                adapter->mng_vlan_id = vid;
        }

        if ((old_vid != (u16)E1000_MNG_VLAN_NONE) && (vid != old_vid))
                e1000_vlan_rx_kill_vid(netdev, htons(ETH_P_8021Q), old_vid);
}

static void e1000_restore_vlan(struct e1000_adapter *adapter)
{
        u16 vid;

        e1000_vlan_rx_add_vid(adapter->netdev, htons(ETH_P_8021Q), 0);

        for_each_set_bit(vid, adapter->active_vlans, VLAN_N_VID)
            e1000_vlan_rx_add_vid(adapter->netdev, htons(ETH_P_8021Q), vid);
}

static void e1000_init_manageability_pt(struct e1000_adapter *adapter)
{
        struct e1000_hw *hw = &adapter->hw;
        u32 manc, manc2h, mdef, i, j;

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

        manc = er32(MANC);

        /* enable receiving management packets to the host. this will probably
         * generate destination unreachable messages from the host OS, but
         * the packets will be handled on SMBUS
         */
        manc |= E1000_MANC_EN_MNG2HOST;
        manc2h = er32(MANC2H);

        switch (hw->mac.type) {
        default:
                manc2h |= (E1000_MANC2H_PORT_623 | E1000_MANC2H_PORT_664);
                break;
        case e1000_82574:
        case e1000_82583:
                /* Check if IPMI pass-through decision filter already exists;
                 * if so, enable it.
                 */
                for (i = 0, j = 0; i < 8; i++) {
                        mdef = er32(MDEF(i));

                        /* Ignore filters with anything other than IPMI ports */
                        if (mdef & ~(E1000_MDEF_PORT_623 | E1000_MDEF_PORT_664))
                                continue;

                        /* Enable this decision filter in MANC2H */
                        if (mdef)
                                manc2h |= (1 << i);

                        j |= mdef;
                }

                if (j == (E1000_MDEF_PORT_623 | E1000_MDEF_PORT_664))
                        break;

                /* Create new decision filter in an empty filter */
                for (i = 0, j = 0; i < 8; i++)
                        if (er32(MDEF(i)) == 0) {
                                ew32(MDEF(i), (E1000_MDEF_PORT_623 |
                                               E1000_MDEF_PORT_664));
                                manc2h |= (1 << 1);
                                j++;
                                break;
                        }

                if (!j)
                        e_warn("Unable to create IPMI pass-through filter\n");
                break;
        }

        ew32(MANC2H, manc2h);
        ew32(MANC, manc);
}

/**
 * e1000_configure_tx - Configure 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)
{
        struct e1000_hw *hw = &adapter->hw;
        struct e1000_ring *tx_ring = adapter->tx_ring;
        u64 tdba;
        u32 tdlen, tctl, tarc;

        /* Setup the HW Tx Head and Tail descriptor pointers */
        tdba = tx_ring->dma;
        tdlen = tx_ring->count * sizeof(struct e1000_tx_desc);
        ew32(TDBAL(0), (tdba & DMA_BIT_MASK(32)));
        ew32(TDBAH(0), (tdba >> 32));
        ew32(TDLEN(0), tdlen);
        ew32(TDH(0), 0);
        ew32(TDT(0), 0);
        tx_ring->head = adapter->hw.hw_addr + E1000_TDH(0);
        tx_ring->tail = adapter->hw.hw_addr + E1000_TDT(0);

        writel(0, tx_ring->head);
        if (adapter->flags2 & FLAG2_PCIM2PCI_ARBITER_WA)
                e1000e_update_tdt_wa(tx_ring, 0);
        else
                writel(0, tx_ring->tail);

        /* Set the Tx Interrupt Delay register */
        ew32(TIDV, adapter->tx_int_delay);
        /* Tx irq moderation */
        ew32(TADV, adapter->tx_abs_int_delay);

        if (adapter->flags2 & FLAG2_DMA_BURST) {
                u32 txdctl = er32(TXDCTL(0));

                txdctl &= ~(E1000_TXDCTL_PTHRESH | E1000_TXDCTL_HTHRESH |
                            E1000_TXDCTL_WTHRESH);
                /* set up some performance related parameters to encourage the
                 * hardware to use the bus more efficiently in bursts, depends
                 * on the tx_int_delay to be enabled,
                 * wthresh = 1 ==> burst write is disabled to avoid Tx stalls
                 * hthresh = 1 ==> prefetch when one or more available
                 * pthresh = 0x1f ==> prefetch if internal cache 31 or less
                 * BEWARE: this seems to work but should be considered first if
                 * there are Tx hangs or other Tx related bugs
                 */
                txdctl |= E1000_TXDCTL_DMA_BURST_ENABLE;
                ew32(TXDCTL(0), txdctl);
        }
        /* erratum work around: set txdctl the same for both queues */
        ew32(TXDCTL(1), er32(TXDCTL(0)));

        /* 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);

        if (adapter->flags & FLAG_TARC_SPEED_MODE_BIT) {
                tarc = er32(TARC(0));
                /* set the speed mode bit, we'll clear it if we're not at
                 * gigabit link later
                 */
#define SPEED_MODE_BIT (1 << 21)
                tarc |= SPEED_MODE_BIT;
                ew32(TARC(0), tarc);
        }

        /* errata: program both queues to unweighted RR */
        if (adapter->flags & FLAG_TARC_SET_BIT_ZERO) {
                tarc = er32(TARC(0));
                tarc |= 1;
                ew32(TARC(0), tarc);
                tarc = er32(TARC(1));
                tarc |= 1;
                ew32(TARC(1), tarc);
        }