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 // SPDX-License-Identifier: GPL-2.0
 /* Copyright(c) 1999 - 2006 Intel Corporation. */
 
 #include "e1000.h"
 #include <net/ip6_checksum.h>
 #include <linux/io.h>
 #include <linux/prefetch.h>
 #include <linux/bitops.h>
 #include <linux/if_vlan.h>
 
 char e1000_driver_name[] = "e1000";
 static char e1000_driver_string[] = "Intel(R) PRO/1000 Network Driver";
 static const char e1000_copyright[] = "Copyright (c) 1999-2006 Intel Corporation.";
 
 /* e1000_pci_tbl - PCI Device ID Table
  *
  * Last entry must be all 0s
  *
  * Macro expands to...
  *   {PCI_DEVICE(PCI_VENDOR_ID_INTEL, device_id)}
  */
 static const struct pci_device_id e1000_pci_tbl[] = {
     INTEL_E1000_ETHERNET_DEVICE(0x1000),
     INTEL_E1000_ETHERNET_DEVICE(0x1001),
     INTEL_E1000_ETHERNET_DEVICE(0x1004),
     INTEL_E1000_ETHERNET_DEVICE(0x1008),
     INTEL_E1000_ETHERNET_DEVICE(0x1009),
     INTEL_E1000_ETHERNET_DEVICE(0x100C),
     INTEL_E1000_ETHERNET_DEVICE(0x100D),
     INTEL_E1000_ETHERNET_DEVICE(0x100E),
     INTEL_E1000_ETHERNET_DEVICE(0x100F),
     INTEL_E1000_ETHERNET_DEVICE(0x1010),
     INTEL_E1000_ETHERNET_DEVICE(0x1011),
     INTEL_E1000_ETHERNET_DEVICE(0x1012),
     INTEL_E1000_ETHERNET_DEVICE(0x1013),
     INTEL_E1000_ETHERNET_DEVICE(0x1014),
     INTEL_E1000_ETHERNET_DEVICE(0x1015),
     INTEL_E1000_ETHERNET_DEVICE(0x1016),
     INTEL_E1000_ETHERNET_DEVICE(0x1017),
     INTEL_E1000_ETHERNET_DEVICE(0x1018),
     INTEL_E1000_ETHERNET_DEVICE(0x1019),
     INTEL_E1000_ETHERNET_DEVICE(0x101A),
     INTEL_E1000_ETHERNET_DEVICE(0x101D),
     INTEL_E1000_ETHERNET_DEVICE(0x101E),
     INTEL_E1000_ETHERNET_DEVICE(0x1026),
     INTEL_E1000_ETHERNET_DEVICE(0x1027),
     INTEL_E1000_ETHERNET_DEVICE(0x1028),
     INTEL_E1000_ETHERNET_DEVICE(0x1075),
     INTEL_E1000_ETHERNET_DEVICE(0x1076),
     INTEL_E1000_ETHERNET_DEVICE(0x1077),
     INTEL_E1000_ETHERNET_DEVICE(0x1078),
     INTEL_E1000_ETHERNET_DEVICE(0x1079),
     INTEL_E1000_ETHERNET_DEVICE(0x107A),
     INTEL_E1000_ETHERNET_DEVICE(0x107B),
     INTEL_E1000_ETHERNET_DEVICE(0x107C),
     INTEL_E1000_ETHERNET_DEVICE(0x108A),
     INTEL_E1000_ETHERNET_DEVICE(0x1099),
     INTEL_E1000_ETHERNET_DEVICE(0x10B5),
     INTEL_E1000_ETHERNET_DEVICE(0x2E6E),
     /* required last entry */
     {0,}
 };
 
 MODULE_DEVICE_TABLE(pci, e1000_pci_tbl);
 
 int e1000_up(struct e1000_adapter *adapter);
 void e1000_down(struct e1000_adapter *adapter);
 void e1000_reinit_locked(struct e1000_adapter *adapter);
 void e1000_reset(struct e1000_adapter *adapter);
 int e1000_setup_all_tx_resources(struct e1000_adapter *adapter);
 int e1000_setup_all_rx_resources(struct e1000_adapter *adapter);
 void e1000_free_all_tx_resources(struct e1000_adapter *adapter);
 void e1000_free_all_rx_resources(struct e1000_adapter *adapter);
 static int e1000_setup_tx_resources(struct e1000_adapter *adapter,
                     struct e1000_tx_ring *txdr);
 static int e1000_setup_rx_resources(struct e1000_adapter *adapter,
                     struct e1000_rx_ring *rxdr);
 static void e1000_free_tx_resources(struct e1000_adapter *adapter,
                     struct e1000_tx_ring *tx_ring);
 static void e1000_free_rx_resources(struct e1000_adapter *adapter,
                     struct e1000_rx_ring *rx_ring);
 void e1000_update_stats(struct e1000_adapter *adapter);
 
 static int e1000_init_module(void);
 static void e1000_exit_module(void);
 static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
 static void e1000_remove(struct pci_dev *pdev);
 static int e1000_alloc_queues(struct e1000_adapter *adapter);
 static int e1000_sw_init(struct e1000_adapter *adapter);
 int e1000_open(struct net_device *netdev);
 int e1000_close(struct net_device *netdev);
 static void e1000_configure_tx(struct e1000_adapter *adapter);
 static void e1000_configure_rx(struct e1000_adapter *adapter);
 static void e1000_setup_rctl(struct e1000_adapter *adapter);
 static void e1000_clean_all_tx_rings(struct e1000_adapter *adapter);
 static void e1000_clean_all_rx_rings(struct e1000_adapter *adapter);
 static void e1000_clean_tx_ring(struct e1000_adapter *adapter,
                 struct e1000_tx_ring *tx_ring);
 static void e1000_clean_rx_ring(struct e1000_adapter *adapter,
                 struct e1000_rx_ring *rx_ring);
 static void e1000_set_rx_mode(struct net_device *netdev);
 static void e1000_update_phy_info_task(struct work_struct *work);
 static void e1000_watchdog(struct work_struct *work);
 static void e1000_82547_tx_fifo_stall_task(struct work_struct *work);
 static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
                     struct net_device *netdev);
 static int e1000_change_mtu(struct net_device *netdev, int new_mtu);
 static int e1000_set_mac(struct net_device *netdev, void *p);
 static irqreturn_t e1000_intr(int irq, void *data);
 static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
                    struct e1000_tx_ring *tx_ring);
 static int e1000_clean(struct napi_struct *napi, int budget);
 static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
                    struct e1000_rx_ring *rx_ring,
                    int *work_done, int work_to_do);
 static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
                      struct e1000_rx_ring *rx_ring,
                      int *work_done, int work_to_do);
 static void e1000_alloc_dummy_rx_buffers(struct e1000_adapter *adapter,
                      struct e1000_rx_ring *rx_ring,
                      int cleaned_count)
 {
 }
 static void e1000_alloc_rx_buffers(struct e1000_adapter *adapter,
                    struct e1000_rx_ring *rx_ring,
                    int cleaned_count);
 static void e1000_alloc_jumbo_rx_buffers(struct e1000_adapter *adapter,
                      struct e1000_rx_ring *rx_ring,
                      int cleaned_count);
 static int e1000_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd);
 static int e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr,
                int cmd);
 static void e1000_enter_82542_rst(struct e1000_adapter *adapter);
 static void e1000_leave_82542_rst(struct e1000_adapter *adapter);
 static void e1000_tx_timeout(struct net_device *dev, unsigned int txqueue);
 static void e1000_reset_task(struct work_struct *work);
 static void e1000_smartspeed(struct e1000_adapter *adapter);
 static int e1000_82547_fifo_workaround(struct e1000_adapter *adapter,
                        struct sk_buff *skb);
 
 static bool e1000_vlan_used(struct e1000_adapter *adapter);
 static void e1000_vlan_mode(struct net_device *netdev,
                 netdev_features_t features);
 static void e1000_vlan_filter_on_off(struct e1000_adapter *adapter,
                      bool filter_on);
 static int e1000_vlan_rx_add_vid(struct net_device *netdev,
                  __be16 proto, u16 vid);
 static int e1000_vlan_rx_kill_vid(struct net_device *netdev,
                   __be16 proto, u16 vid);
 static void e1000_restore_vlan(struct e1000_adapter *adapter);
 
 static int __maybe_unused e1000_suspend(struct device *dev);
 static int __maybe_unused e1000_resume(struct device *dev);
 static void e1000_shutdown(struct pci_dev *pdev);
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
 /* for netdump / net console */
 static void e1000_netpoll (struct net_device *netdev);
 #endif
 
 #define COPYBREAK_DEFAULT 256
 static unsigned int copybreak __read_mostly = COPYBREAK_DEFAULT;
 module_param(copybreak, uint, 0644);
 MODULE_PARM_DESC(copybreak,
     "Maximum size of packet that is copied to a new buffer on receive");
 
 static pci_ers_result_t e1000_io_error_detected(struct pci_dev *pdev,
                         pci_channel_state_t state);
 static pci_ers_result_t e1000_io_slot_reset(struct pci_dev *pdev);
 static void e1000_io_resume(struct pci_dev *pdev);
 
 static const struct pci_error_handlers e1000_err_handler = {
     .error_detected = e1000_io_error_detected,
     .slot_reset = e1000_io_slot_reset,
     .resume = e1000_io_resume,
 };
 
 static SIMPLE_DEV_PM_OPS(e1000_pm_ops, e1000_suspend, e1000_resume);
 
 static struct pci_driver e1000_driver = {
     .name     = e1000_driver_name,
     .id_table = e1000_pci_tbl,
     .probe    = e1000_probe,
     .remove   = e1000_remove,
     .driver = {
         .pm = &e1000_pm_ops,
     },
     .shutdown = e1000_shutdown,
     .err_handler = &e1000_err_handler
 };
 
 MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
 MODULE_DESCRIPTION("Intel(R) PRO/1000 Network Driver");
 MODULE_LICENSE("GPL v2");
 
 #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)");
 
 /**
  * e1000_get_hw_dev - helper function for getting netdev
  * @hw: pointer to HW struct
  *
  * return device used by hardware layer to print debugging information
  *
  **/
 struct net_device *e1000_get_hw_dev(struct e1000_hw *hw)
 {
     struct e1000_adapter *adapter = hw->back;
     return adapter->netdev;
 }
 
 /**
  * e1000_init_module - Driver Registration Routine
  *
  * e1000_init_module is the first routine called when the driver is
  * loaded. All it does is register with the PCI subsystem.
  **/
 static int __init e1000_init_module(void)
 {
     int ret;
     pr_info("%s\n", e1000_driver_string);
 
     pr_info("%s\n", e1000_copyright);
 
     ret = pci_register_driver(&e1000_driver);
     if (copybreak != COPYBREAK_DEFAULT) {
         if (copybreak == 0)
             pr_info("copybreak disabled\n");
         else
             pr_info("copybreak enabled for "
                    "packets <= %u bytes\n", copybreak);
     }
     return ret;
 }
 
 module_init(e1000_init_module);
 
 /**
  * e1000_exit_module - Driver Exit Cleanup Routine
  *
  * e1000_exit_module is called just before the driver is removed
  * from memory.
  **/
 static void __exit e1000_exit_module(void)
 {
     pci_unregister_driver(&e1000_driver);
 }
 
 module_exit(e1000_exit_module);
 
 static int e1000_request_irq(struct e1000_adapter *adapter)
 {
     struct net_device *netdev = adapter->netdev;
     irq_handler_t handler = e1000_intr;
     int irq_flags = IRQF_SHARED;
     int err;
 
     err = request_irq(adapter->pdev->irq, handler, irq_flags, netdev->name,
               netdev);
     if (err) {
         e_err(probe, "Unable to allocate interrupt Error: %d\n", err);
     }
 
     return err;
 }
 
 static void e1000_free_irq(struct e1000_adapter *adapter)
 {
     struct net_device *netdev = adapter->netdev;
 
     free_irq(adapter->pdev->irq, netdev);
 }
 
 /**
  * e1000_irq_disable - Mask off interrupt generation on the NIC
  * @adapter: board private structure
  **/
 static void e1000_irq_disable(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     ew32(IMC, ~0);
     E1000_WRITE_FLUSH();
     synchronize_irq(adapter->pdev->irq);
 }
 
 /**
  * e1000_irq_enable - Enable default interrupt generation settings
  * @adapter: board private structure
  **/
 static void e1000_irq_enable(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     ew32(IMS, IMS_ENABLE_MASK);
     E1000_WRITE_FLUSH();
 }
 
 static void e1000_update_mng_vlan(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     u16 vid = hw->mng_cookie.vlan_id;
     u16 old_vid = adapter->mng_vlan_id;
 
     if (!e1000_vlan_used(adapter))
         return;
 
     if (!test_bit(vid, adapter->active_vlans)) {
         if (hw->mng_cookie.status &
             E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT) {
             e1000_vlan_rx_add_vid(netdev, htons(ETH_P_8021Q), vid);
             adapter->mng_vlan_id = vid;
         } else {
             adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;
         }
         if ((old_vid != (u16)E1000_MNG_VLAN_NONE) &&
             (vid != old_vid) &&
             !test_bit(old_vid, adapter->active_vlans))
             e1000_vlan_rx_kill_vid(netdev, htons(ETH_P_8021Q),
                            old_vid);
     } else {
         adapter->mng_vlan_id = vid;
     }
 }
 
 static void e1000_init_manageability(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     if (adapter->en_mng_pt) {
         u32 manc = er32(MANC);
 
         /* disable hardware interception of ARP */
         manc &= ~(E1000_MANC_ARP_EN);
 
         ew32(MANC, manc);
     }
 }
 
 static void e1000_release_manageability(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     if (adapter->en_mng_pt) {
         u32 manc = er32(MANC);
 
         /* re-enable hardware interception of ARP */
         manc |= E1000_MANC_ARP_EN;
 
         ew32(MANC, manc);
     }
 }
 
 /**
  * e1000_configure - configure the hardware for RX and TX
  * @adapter: private board structure
  **/
 static void e1000_configure(struct e1000_adapter *adapter)
 {
     struct net_device *netdev = adapter->netdev;
     int i;
 
     e1000_set_rx_mode(netdev);
 
     e1000_restore_vlan(adapter);
     e1000_init_manageability(adapter);
 
     e1000_configure_tx(adapter);
     e1000_setup_rctl(adapter);
     e1000_configure_rx(adapter);
     /* call E1000_DESC_UNUSED which always leaves
      * at least 1 descriptor unused to make sure
      * next_to_use != next_to_clean
      */
     for (i = 0; i < adapter->num_rx_queues; i++) {
         struct e1000_rx_ring *ring = &adapter->rx_ring[i];
         adapter->alloc_rx_buf(adapter, ring,
                       E1000_DESC_UNUSED(ring));
     }
 }
 
 int e1000_up(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     /* hardware has been reset, we need to reload some things */
     e1000_configure(adapter);
 
     clear_bit(__E1000_DOWN, &adapter->flags);
 
     napi_enable(&adapter->napi);
 
     e1000_irq_enable(adapter);
 
     netif_wake_queue(adapter->netdev);
 
     /* fire a link change interrupt to start the watchdog */
     ew32(ICS, E1000_ICS_LSC);
     return 0;
 }
 
 /**
  * e1000_power_up_phy - restore link in case the phy was powered down
  * @adapter: address of board private structure
  *
  * The phy may be powered down to save power and turn off link when the
  * driver is unloaded and wake on lan is not enabled (among others)
  * *** this routine MUST be followed by a call to e1000_reset ***
  **/
 void e1000_power_up_phy(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     u16 mii_reg = 0;
 
     /* Just clear the power down bit to wake the phy back up */
     if (hw->media_type == e1000_media_type_copper) {
         /* according to the manual, the phy will retain its
          * settings across a power-down/up cycle
          */
         e1000_read_phy_reg(hw, PHY_CTRL, &mii_reg);
         mii_reg &= ~MII_CR_POWER_DOWN;
         e1000_write_phy_reg(hw, PHY_CTRL, mii_reg);
     }
 }
 
 static void e1000_power_down_phy(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     /* Power down the PHY so no link is implied when interface is down *
      * The PHY cannot be powered down if any of the following is true *
      * (a) WoL is enabled
      * (b) AMT is active
      * (c) SoL/IDER session is active
      */
     if (!adapter->wol && hw->mac_type >= e1000_82540 &&
        hw->media_type == e1000_media_type_copper) {
         u16 mii_reg = 0;
 
         switch (hw->mac_type) {
         case e1000_82540:
         case e1000_82545:
         case e1000_82545_rev_3:
         case e1000_82546:
         case e1000_ce4100:
         case e1000_82546_rev_3:
         case e1000_82541:
         case e1000_82541_rev_2:
         case e1000_82547:
         case e1000_82547_rev_2:
             if (er32(MANC) & E1000_MANC_SMBUS_EN)
                 goto out;
             break;
         default:
             goto out;
         }
         e1000_read_phy_reg(hw, PHY_CTRL, &mii_reg);
         mii_reg |= MII_CR_POWER_DOWN;
         e1000_write_phy_reg(hw, PHY_CTRL, mii_reg);
         msleep(1);
     }
 out:
     return;
 }
 
 static void e1000_down_and_stop(struct e1000_adapter *adapter)
 {
     set_bit(__E1000_DOWN, &adapter->flags);
 
     cancel_delayed_work_sync(&adapter->watchdog_task);
 
     /*
      * Since the watchdog task can reschedule other tasks, we should cancel
      * it first, otherwise we can run into the situation when a work is
      * still running after the adapter has been turned down.
      */
 
     cancel_delayed_work_sync(&adapter->phy_info_task);
     cancel_delayed_work_sync(&adapter->fifo_stall_task);
 
     /* Only kill reset task if adapter is not resetting */
     if (!test_bit(__E1000_RESETTING, &adapter->flags))
         cancel_work_sync(&adapter->reset_task);
 }
 
 void e1000_down(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     u32 rctl, tctl;
 
     /* disable receives in the hardware */
     rctl = er32(RCTL);
     ew32(RCTL, rctl & ~E1000_RCTL_EN);
     /* flush and sleep below */
 
     netif_tx_disable(netdev);
 
     /* disable transmits in the hardware */
     tctl = er32(TCTL);
     tctl &= ~E1000_TCTL_EN;
     ew32(TCTL, tctl);
     /* flush both disables and wait for them to finish */
     E1000_WRITE_FLUSH();
     msleep(10);
 
     /* Set the carrier off after transmits have been disabled in the
      * hardware, to avoid race conditions with e1000_watchdog() (which
      * may be running concurrently to us, checking for the carrier
      * bit to decide whether it should enable transmits again). Such
      * a race condition would result into transmission being disabled
      * in the hardware until the next IFF_DOWN+IFF_UP cycle.
      */
     netif_carrier_off(netdev);
 
     napi_disable(&adapter->napi);
 
     e1000_irq_disable(adapter);
 
     /* Setting DOWN must be after irq_disable to prevent
      * a screaming interrupt.  Setting DOWN also prevents
      * tasks from rescheduling.
      */
     e1000_down_and_stop(adapter);
 
     adapter->link_speed = 0;
     adapter->link_duplex = 0;
 
     e1000_reset(adapter);
     e1000_clean_all_tx_rings(adapter);
     e1000_clean_all_rx_rings(adapter);
 }
 
 void e1000_reinit_locked(struct e1000_adapter *adapter)
 {
     while (test_and_set_bit(__E1000_RESETTING, &adapter->flags))
         msleep(1);
 
     /* only run the task if not already down */
     if (!test_bit(__E1000_DOWN, &adapter->flags)) {
         e1000_down(adapter);
         e1000_up(adapter);
     }
 
     clear_bit(__E1000_RESETTING, &adapter->flags);
 }
 
 void e1000_reset(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     u32 pba = 0, tx_space, min_tx_space, min_rx_space;
     bool legacy_pba_adjust = false;
     u16 hwm;
 
     /* Repartition Pba for greater than 9k mtu
      * To take effect CTRL.RST is required.
      */
 
     switch (hw->mac_type) {
     case e1000_82542_rev2_0:
     case e1000_82542_rev2_1:
     case e1000_82543:
     case e1000_82544:
     case e1000_82540:
     case e1000_82541:
     case e1000_82541_rev_2:
         legacy_pba_adjust = true;
         pba = E1000_PBA_48K;
         break;
     case e1000_82545:
     case e1000_82545_rev_3:
     case e1000_82546:
     case e1000_ce4100:
     case e1000_82546_rev_3:
         pba = E1000_PBA_48K;
         break;
     case e1000_82547:
     case e1000_82547_rev_2:
         legacy_pba_adjust = true;
         pba = E1000_PBA_30K;
         break;
     case e1000_undefined:
     case e1000_num_macs:
         break;
     }
 
     if (legacy_pba_adjust) {
         if (hw->max_frame_size > E1000_RXBUFFER_8192)
             pba -= 8; /* allocate more FIFO for Tx */
 
         if (hw->mac_type == e1000_82547) {
             adapter->tx_fifo_head = 0;
             adapter->tx_head_addr = pba << E1000_TX_HEAD_ADDR_SHIFT;
             adapter->tx_fifo_size =
                 (E1000_PBA_40K - pba) << E1000_PBA_BYTES_SHIFT;
             atomic_set(&adapter->tx_fifo_stall, 0);
         }
     } else if (hw->max_frame_size >  ETH_FRAME_LEN + ETH_FCS_LEN) {
         /* adjust PBA for jumbo frames */
         ew32(PBA, pba);
 
         /* To maintain wire speed transmits, the Tx FIFO should be
          * large enough to accommodate two full transmit packets,
          * rounded up to the next 1KB and expressed in KB.  Likewise,
          * the Rx FIFO should be large enough to accommodate at least
          * one full receive packet and is similarly rounded up and
          * expressed in KB.
          */
         pba = er32(PBA);
         /* upper 16 bits has Tx packet buffer allocation size in KB */
         tx_space = pba >> 16;
         /* lower 16 bits has Rx packet buffer allocation size in KB */
         pba &= 0xffff;
         /* the Tx fifo also stores 16 bytes of information about the Tx
          * but don't include ethernet FCS because hardware appends it
          */
         min_tx_space = (hw->max_frame_size +
                 sizeof(struct e1000_tx_desc) -
                 ETH_FCS_LEN) * 2;
         min_tx_space = ALIGN(min_tx_space, 1024);
         min_tx_space >>= 10;
         /* software strips receive CRC, so leave room for it */
         min_rx_space = hw->max_frame_size;
         min_rx_space = ALIGN(min_rx_space, 1024);
         min_rx_space >>= 10;
 
         /* If current Tx allocation is less than the min Tx FIFO size,
          * and the min Tx FIFO size is less than the current Rx FIFO
          * allocation, take space away from current Rx allocation
          */
         if (tx_space < min_tx_space &&
             ((min_tx_space - tx_space) < pba)) {
             pba = pba - (min_tx_space - tx_space);
 
             /* PCI/PCIx hardware has PBA alignment constraints */
             switch (hw->mac_type) {
             case e1000_82545 ... e1000_82546_rev_3:
                 pba &= ~(E1000_PBA_8K - 1);
                 break;
             default:
                 break;
             }
 
             /* if short on Rx space, Rx wins and must trump Tx
              * adjustment or use Early Receive if available
              */
             if (pba < min_rx_space)
                 pba = min_rx_space;
         }
     }
 
     ew32(PBA, pba);
 
     /* flow control settings:
      * The high water mark must be low enough to fit one full frame
      * (or the size used for early receive) above it in the Rx FIFO.
      * Set it to the lower of:
      * - 90% of the Rx FIFO size, and
      * - the full Rx FIFO size minus the early receive size (for parts
      *   with ERT support assuming ERT set to E1000_ERT_2048), or
      * - the full Rx FIFO size minus one full frame
      */
     hwm = min(((pba << 10) * 9 / 10),
           ((pba << 10) - hw->max_frame_size));
 
     hw->fc_high_water = hwm & 0xFFF8;   /* 8-byte granularity */
     hw->fc_low_water = hw->fc_high_water - 8;
     hw->fc_pause_time = E1000_FC_PAUSE_TIME;
     hw->fc_send_xon = 1;
     hw->fc = hw->original_fc;
 
     /* Allow time for pending master requests to run */
     e1000_reset_hw(hw);
     if (hw->mac_type >= e1000_82544)
         ew32(WUC, 0);
 
     if (e1000_init_hw(hw))
         e_dev_err("Hardware Error\n");
     e1000_update_mng_vlan(adapter);
 
     /* if (adapter->hwflags & HWFLAGS_PHY_PWR_BIT) { */
     if (hw->mac_type >= e1000_82544 &&
         hw->autoneg == 1 &&
         hw->autoneg_advertised == ADVERTISE_1000_FULL) {
         u32 ctrl = er32(CTRL);
         /* clear phy power management bit if we are in gig only mode,
          * which if enabled will attempt negotiation to 100Mb, which
          * can cause a loss of link at power off or driver unload
          */
         ctrl &= ~E1000_CTRL_SWDPIN3;
         ew32(CTRL, ctrl);
     }
 
     /* Enable h/w to recognize an 802.1Q VLAN Ethernet packet */
     ew32(VET, ETHERNET_IEEE_VLAN_TYPE);
 
     e1000_reset_adaptive(hw);
     e1000_phy_get_info(hw, &adapter->phy_info);
 
     e1000_release_manageability(adapter);
 }
 
 /* Dump the eeprom for users having checksum issues */
 static void e1000_dump_eeprom(struct e1000_adapter *adapter)
 {
     struct net_device *netdev = adapter->netdev;
     struct ethtool_eeprom eeprom;
     const struct ethtool_ops *ops = netdev->ethtool_ops;
     u8 *data;
     int i;
     u16 csum_old, csum_new = 0;
 
     eeprom.len = ops->get_eeprom_len(netdev);
     eeprom.offset = 0;
 
     data = kmalloc(eeprom.len, GFP_KERNEL);
     if (!data)
         return;
 
     ops->get_eeprom(netdev, &eeprom, data);
 
     csum_old = (data[EEPROM_CHECKSUM_REG * 2]) +
            (data[EEPROM_CHECKSUM_REG * 2 + 1] << 8);
     for (i = 0; i < EEPROM_CHECKSUM_REG * 2; i += 2)
         csum_new += data[i] + (data[i + 1] << 8);
     csum_new = EEPROM_SUM - csum_new;
 
     pr_err("/*********************/\n");
     pr_err("Current EEPROM Checksum : 0x%04x\n", csum_old);
     pr_err("Calculated              : 0x%04x\n", csum_new);
 
     pr_err("Offset    Values\n");
     pr_err("========  ======\n");
     print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, data, 128, 0);
 
     pr_err("Include this output when contacting your support provider.\n");
     pr_err("This is not a software error! Something bad happened to\n");
     pr_err("your hardware or EEPROM image. Ignoring this problem could\n");
     pr_err("result in further problems, possibly loss of data,\n");
     pr_err("corruption or system hangs!\n");
     pr_err("The MAC Address will be reset to 00:00:00:00:00:00,\n");
     pr_err("which is invalid and requires you to set the proper MAC\n");
     pr_err("address manually before continuing to enable this network\n");
     pr_err("device. Please inspect the EEPROM dump and report the\n");
     pr_err("issue to your hardware vendor or Intel Customer Support.\n");
     pr_err("/*********************/\n");
 
     kfree(data);
 }
 
 /**
  * e1000_is_need_ioport - determine if an adapter needs ioport resources or not
  * @pdev: PCI device information struct
  *
  * Return true if an adapter needs ioport resources
  **/
 static int e1000_is_need_ioport(struct pci_dev *pdev)
 {
     switch (pdev->device) {
     case E1000_DEV_ID_82540EM:
     case E1000_DEV_ID_82540EM_LOM:
     case E1000_DEV_ID_82540EP:
     case E1000_DEV_ID_82540EP_LOM:
     case E1000_DEV_ID_82540EP_LP:
     case E1000_DEV_ID_82541EI:
     case E1000_DEV_ID_82541EI_MOBILE:
     case E1000_DEV_ID_82541ER:
     case E1000_DEV_ID_82541ER_LOM:
     case E1000_DEV_ID_82541GI:
     case E1000_DEV_ID_82541GI_LF:
     case E1000_DEV_ID_82541GI_MOBILE:
     case E1000_DEV_ID_82544EI_COPPER:
     case E1000_DEV_ID_82544EI_FIBER:
     case E1000_DEV_ID_82544GC_COPPER:
     case E1000_DEV_ID_82544GC_LOM:
     case E1000_DEV_ID_82545EM_COPPER:
     case E1000_DEV_ID_82545EM_FIBER:
     case E1000_DEV_ID_82546EB_COPPER:
     case E1000_DEV_ID_82546EB_FIBER:
     case E1000_DEV_ID_82546EB_QUAD_COPPER:
         return true;
     default:
         return false;
     }
 }
 
 static netdev_features_t e1000_fix_features(struct net_device *netdev,
     netdev_features_t features)
 {
     /* Since there is no support for separate Rx/Tx vlan accel
      * enable/disable make sure Tx flag is always in same state as Rx.
      */
     if (features & NETIF_F_HW_VLAN_CTAG_RX)
         features |= NETIF_F_HW_VLAN_CTAG_TX;
     else
         features &= ~NETIF_F_HW_VLAN_CTAG_TX;
 
     return features;
 }
 
 static int e1000_set_features(struct net_device *netdev,
     netdev_features_t features)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     netdev_features_t changed = features ^ netdev->features;
 
     if (changed & NETIF_F_HW_VLAN_CTAG_RX)
         e1000_vlan_mode(netdev, features);
 
     if (!(changed & (NETIF_F_RXCSUM | NETIF_F_RXALL)))
         return 0;
 
     netdev->features = features;
     adapter->rx_csum = !!(features & NETIF_F_RXCSUM);
 
     if (netif_running(netdev))
         e1000_reinit_locked(adapter);
     else
         e1000_reset(adapter);
 
     return 1;
 }
 
 static const struct net_device_ops e1000_netdev_ops = {
     .ndo_open       = e1000_open,
     .ndo_stop       = e1000_close,
     .ndo_start_xmit     = e1000_xmit_frame,
     .ndo_set_rx_mode    = e1000_set_rx_mode,
     .ndo_set_mac_address    = e1000_set_mac,
     .ndo_tx_timeout     = e1000_tx_timeout,
     .ndo_change_mtu     = e1000_change_mtu,
     .ndo_eth_ioctl      = e1000_ioctl,
     .ndo_validate_addr  = eth_validate_addr,
     .ndo_vlan_rx_add_vid    = e1000_vlan_rx_add_vid,
     .ndo_vlan_rx_kill_vid   = e1000_vlan_rx_kill_vid,
 #ifdef CONFIG_NET_POLL_CONTROLLER
     .ndo_poll_controller    = e1000_netpoll,
 #endif
     .ndo_fix_features   = e1000_fix_features,
     .ndo_set_features   = e1000_set_features,
 };
 
 /**
  * e1000_init_hw_struct - initialize members of hw struct
  * @adapter: board private struct
  * @hw: structure used by e1000_hw.c
  *
  * Factors out initialization of the e1000_hw struct to its own function
  * that can be called very early at init (just after struct allocation).
  * Fields are initialized based on PCI device information and
  * OS network device settings (MTU size).
  * Returns negative error codes if MAC type setup fails.
  */
 static int e1000_init_hw_struct(struct e1000_adapter *adapter,
                 struct e1000_hw *hw)
 {
     struct pci_dev *pdev = adapter->pdev;
 
     /* PCI config space info */
     hw->vendor_id = pdev->vendor;
     hw->device_id = pdev->device;
     hw->subsystem_vendor_id = pdev->subsystem_vendor;
     hw->subsystem_id = pdev->subsystem_device;
     hw->revision_id = pdev->revision;
 
     pci_read_config_word(pdev, PCI_COMMAND, &hw->pci_cmd_word);
 
     hw->max_frame_size = adapter->netdev->mtu +
                  ENET_HEADER_SIZE + ETHERNET_FCS_SIZE;
     hw->min_frame_size = MINIMUM_ETHERNET_FRAME_SIZE;
 
     /* identify the MAC */
     if (e1000_set_mac_type(hw)) {
         e_err(probe, "Unknown MAC Type\n");
         return -EIO;
     }
 
     switch (hw->mac_type) {
     default:
         break;
     case e1000_82541:
     case e1000_82547:
     case e1000_82541_rev_2:
     case e1000_82547_rev_2:
         hw->phy_init_script = 1;
         break;
     }
 
     e1000_set_media_type(hw);
     e1000_get_bus_info(hw);
 
     hw->wait_autoneg_complete = false;
     hw->tbi_compatibility_en = true;
     hw->adaptive_ifs = true;
 
     /* Copper options */
 
     if (hw->media_type == e1000_media_type_copper) {
         hw->mdix = AUTO_ALL_MODES;
         hw->disable_polarity_correction = false;
         hw->master_slave = E1000_MASTER_SLAVE;
     }
 
     return 0;
 }
 
 /**
  * e1000_probe - Device Initialization Routine
  * @pdev: PCI device information struct
  * @ent: entry in e1000_pci_tbl
  *
  * Returns 0 on success, negative on failure
  *
  * e1000_probe initializes an adapter identified by a pci_dev structure.
  * The OS initialization, configuring of the adapter private structure,
  * and a hardware reset occur.
  **/
 static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
     struct net_device *netdev;
     struct e1000_adapter *adapter = NULL;
     struct e1000_hw *hw;
 
     static int cards_found;
     static int global_quad_port_a; /* global ksp3 port a indication */
     int i, err, pci_using_dac;
     u16 eeprom_data = 0;
     u16 tmp = 0;
     u16 eeprom_apme_mask = E1000_EEPROM_APME;
     int bars, need_ioport;
     bool disable_dev = false;
 
     /* do not allocate ioport bars when not needed */
     need_ioport = e1000_is_need_ioport(pdev);
     if (need_ioport) {
         bars = pci_select_bars(pdev, IORESOURCE_MEM | IORESOURCE_IO);
         err = pci_enable_device(pdev);
     } else {
         bars = pci_select_bars(pdev, IORESOURCE_MEM);
         err = pci_enable_device_mem(pdev);
     }
     if (err)
         return err;
 
     err = pci_request_selected_regions(pdev, bars, e1000_driver_name);
     if (err)
         goto err_pci_reg;
 
     pci_set_master(pdev);
     err = pci_save_state(pdev);
     if (err)
         goto err_alloc_etherdev;
 
     err = -ENOMEM;
     netdev = alloc_etherdev(sizeof(struct e1000_adapter));
     if (!netdev)
         goto err_alloc_etherdev;
 
     SET_NETDEV_DEV(netdev, &pdev->dev);
 
     pci_set_drvdata(pdev, netdev);
     adapter = netdev_priv(netdev);
     adapter->netdev = netdev;
     adapter->pdev = pdev;
     adapter->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
     adapter->bars = bars;
     adapter->need_ioport = need_ioport;
 
     hw = &adapter->hw;
     hw->back = adapter;
 
     err = -EIO;
     hw->hw_addr = pci_ioremap_bar(pdev, BAR_0);
     if (!hw->hw_addr)
         goto err_ioremap;
 
     if (adapter->need_ioport) {
         for (i = BAR_1; i < PCI_STD_NUM_BARS; i++) {
             if (pci_resource_len(pdev, i) == 0)
                 continue;
             if (pci_resource_flags(pdev, i) & IORESOURCE_IO) {
                 hw->io_base = pci_resource_start(pdev, i);
                 break;
             }
         }
     }
 
     /* make ready for any if (hw->...) below */
     err = e1000_init_hw_struct(adapter, hw);
     if (err)
         goto err_sw_init;
 
     /* there is a workaround being applied below that limits
      * 64-bit DMA addresses to 64-bit hardware.  There are some
      * 32-bit adapters that Tx hang when given 64-bit DMA addresses
      */
     pci_using_dac = 0;
     if ((hw->bus_type == e1000_bus_type_pcix) &&
         !dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) {
         pci_using_dac = 1;
     } else {
         err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
         if (err) {
             pr_err("No usable DMA config, aborting\n");
             goto err_dma;
         }
     }
 
     netdev->netdev_ops = &e1000_netdev_ops;
     e1000_set_ethtool_ops(netdev);
     netdev->watchdog_timeo = 5 * HZ;
     netif_napi_add(netdev, &adapter->napi, e1000_clean, 64);
 
     strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);
 
     adapter->bd_number = cards_found;
 
     /* setup the private structure */
 
     err = e1000_sw_init(adapter);
     if (err)
         goto err_sw_init;
 
     err = -EIO;
     if (hw->mac_type == e1000_ce4100) {
         hw->ce4100_gbe_mdio_base_virt =
                     ioremap(pci_resource_start(pdev, BAR_1),
                         pci_resource_len(pdev, BAR_1));
 
         if (!hw->ce4100_gbe_mdio_base_virt)
             goto err_mdio_ioremap;
     }
 
     if (hw->mac_type >= e1000_82543) {
         netdev->hw_features = NETIF_F_SG |
                    NETIF_F_HW_CSUM |
                    NETIF_F_HW_VLAN_CTAG_RX;
         netdev->features = NETIF_F_HW_VLAN_CTAG_TX |
                    NETIF_F_HW_VLAN_CTAG_FILTER;
     }
 
     if ((hw->mac_type >= e1000_82544) &&
        (hw->mac_type != e1000_82547))
         netdev->hw_features |= NETIF_F_TSO;
 
     netdev->priv_flags |= IFF_SUPP_NOFCS;
 
     netdev->features |= netdev->hw_features;
     netdev->hw_features |= (NETIF_F_RXCSUM |
                 NETIF_F_RXALL |
                 NETIF_F_RXFCS);
 
     if (pci_using_dac) {
         netdev->features |= NETIF_F_HIGHDMA;
         netdev->vlan_features |= NETIF_F_HIGHDMA;
     }
 
     netdev->vlan_features |= (NETIF_F_TSO |
                   NETIF_F_HW_CSUM |
                   NETIF_F_SG);
 
     /* Do not set IFF_UNICAST_FLT for VMWare's 82545EM */
     if (hw->device_id != E1000_DEV_ID_82545EM_COPPER ||
         hw->subsystem_vendor_id != PCI_VENDOR_ID_VMWARE)
         netdev->priv_flags |= IFF_UNICAST_FLT;
 
     /* MTU range: 46 - 16110 */
     netdev->min_mtu = ETH_ZLEN - ETH_HLEN;
     netdev->max_mtu = MAX_JUMBO_FRAME_SIZE - (ETH_HLEN + ETH_FCS_LEN);
 
     adapter->en_mng_pt = e1000_enable_mng_pass_thru(hw);
 
     /* initialize eeprom parameters */
     if (e1000_init_eeprom_params(hw)) {
         e_err(probe, "EEPROM initialization failed\n");
         goto err_eeprom;
     }
 
     /* before reading the EEPROM, reset the controller to
      * put the device in a known good starting state
      */
 
     e1000_reset_hw(hw);
 
     /* make sure the EEPROM is good */
     if (e1000_validate_eeprom_checksum(hw) < 0) {
         e_err(probe, "The EEPROM Checksum Is Not Valid\n");
         e1000_dump_eeprom(adapter);
         /* set MAC address to all zeroes to invalidate and temporary
          * disable this device for the user. This blocks regular
          * traffic while still permitting ethtool ioctls from reaching
          * the hardware as well as allowing the user to run the
          * interface after manually setting a hw addr using
          * `ip set address`
          */
         memset(hw->mac_addr, 0, netdev->addr_len);
     } else {
         /* copy the MAC address out of the EEPROM */
         if (e1000_read_mac_addr(hw))
             e_err(probe, "EEPROM Read Error\n");
     }
     /* don't block initialization here due to bad MAC address */
     eth_hw_addr_set(netdev, hw->mac_addr);
 
     if (!is_valid_ether_addr(netdev->dev_addr))
         e_err(probe, "Invalid MAC Address\n");
 
 
     INIT_DELAYED_WORK(&adapter->watchdog_task, e1000_watchdog);
     INIT_DELAYED_WORK(&adapter->fifo_stall_task,
               e1000_82547_tx_fifo_stall_task);
     INIT_DELAYED_WORK(&adapter->phy_info_task, e1000_update_phy_info_task);
     INIT_WORK(&adapter->reset_task, e1000_reset_task);
 
     e1000_check_options(adapter);
 
     /* Initial Wake on LAN setting
      * If APM wake is enabled in the EEPROM,
      * enable the ACPI Magic Packet filter
      */
 
     switch (hw->mac_type) {
     case e1000_82542_rev2_0:
     case e1000_82542_rev2_1:
     case e1000_82543:
         break;
     case e1000_82544:
         e1000_read_eeprom(hw,
             EEPROM_INIT_CONTROL2_REG, 1, &eeprom_data);
         eeprom_apme_mask = E1000_EEPROM_82544_APM;
         break;
     case e1000_82546:
     case e1000_82546_rev_3:
         if (er32(STATUS) & E1000_STATUS_FUNC_1) {
             e1000_read_eeprom(hw,
                 EEPROM_INIT_CONTROL3_PORT_B, 1, &eeprom_data);
             break;
         }
         fallthrough;
     default:
         e1000_read_eeprom(hw,
             EEPROM_INIT_CONTROL3_PORT_A, 1, &eeprom_data);
         break;
     }
     if (eeprom_data & eeprom_apme_mask)
         adapter->eeprom_wol |= E1000_WUFC_MAG;
 
     /* now that we have the eeprom settings, apply the special cases
      * where the eeprom may be wrong or the board simply won't support
      * wake on lan on a particular port
      */
     switch (pdev->device) {
     case E1000_DEV_ID_82546GB_PCIE:
         adapter->eeprom_wol = 0;
         break;
     case E1000_DEV_ID_82546EB_FIBER:
     case E1000_DEV_ID_82546GB_FIBER:
         /* Wake events only supported on port A for dual fiber
          * regardless of eeprom setting
          */
         if (er32(STATUS) & E1000_STATUS_FUNC_1)
             adapter->eeprom_wol = 0;
         break;
     case E1000_DEV_ID_82546GB_QUAD_COPPER_KSP3:
         /* if quad port adapter, disable WoL on all but port A */
         if (global_quad_port_a != 0)
             adapter->eeprom_wol = 0;
         else
             adapter->quad_port_a = true;
         /* Reset for multiple quad port adapters */
         if (++global_quad_port_a == 4)
             global_quad_port_a = 0;
         break;
     }
 
     /* initialize the wol settings based on the eeprom settings */
     adapter->wol = adapter->eeprom_wol;
     device_set_wakeup_enable(&adapter->pdev->dev, adapter->wol);
 
     /* Auto detect PHY address */
     if (hw->mac_type == e1000_ce4100) {
         for (i = 0; i < 32; i++) {
             hw->phy_addr = i;
             e1000_read_phy_reg(hw, PHY_ID2, &tmp);
 
             if (tmp != 0 && tmp != 0xFF)
                 break;
         }
 
         if (i >= 32)
             goto err_eeprom;
     }
 
     /* reset the hardware with the new settings */
     e1000_reset(adapter);
 
     strcpy(netdev->name, "eth%d");
     err = register_netdev(netdev);
     if (err)
         goto err_register;
 
     e1000_vlan_filter_on_off(adapter, false);
 
     /* print bus type/speed/width info */
     e_info(probe, "(PCI%s:%dMHz:%d-bit) %pM\n",
            ((hw->bus_type == e1000_bus_type_pcix) ? "-X" : ""),
            ((hw->bus_speed == e1000_bus_speed_133) ? 133 :
         (hw->bus_speed == e1000_bus_speed_120) ? 120 :
         (hw->bus_speed == e1000_bus_speed_100) ? 100 :
         (hw->bus_speed == e1000_bus_speed_66) ? 66 : 33),
            ((hw->bus_width == e1000_bus_width_64) ? 64 : 32),
            netdev->dev_addr);
 
     /* carrier off reporting is important to ethtool even BEFORE open */
     netif_carrier_off(netdev);
 
     e_info(probe, "Intel(R) PRO/1000 Network Connection\n");
 
     cards_found++;
     return 0;
 
 err_register:
 err_eeprom:
     e1000_phy_hw_reset(hw);
 
     if (hw->flash_address)
         iounmap(hw->flash_address);
     kfree(adapter->tx_ring);
     kfree(adapter->rx_ring);
 err_dma:
 err_sw_init:
 err_mdio_ioremap:
     iounmap(hw->ce4100_gbe_mdio_base_virt);
     iounmap(hw->hw_addr);
 err_ioremap:
     disable_dev = !test_and_set_bit(__E1000_DISABLED, &adapter->flags);
     free_netdev(netdev);
 err_alloc_etherdev:
     pci_release_selected_regions(pdev, bars);
 err_pci_reg:
     if (!adapter || disable_dev)
         pci_disable_device(pdev);
     return err;
 }
 
 /**
  * e1000_remove - Device Removal Routine
  * @pdev: PCI device information struct
  *
  * e1000_remove is called by the PCI subsystem to alert the driver
  * that it should release a PCI device. That could be caused by a
  * Hot-Plug event, or because the driver is going to be removed from
  * memory.
  **/
 static void e1000_remove(struct pci_dev *pdev)
 {
     struct net_device *netdev = pci_get_drvdata(pdev);
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     bool disable_dev;
 
     e1000_down_and_stop(adapter);
     e1000_release_manageability(adapter);
 
     unregister_netdev(netdev);
 
     e1000_phy_hw_reset(hw);
 
     kfree(adapter->tx_ring);
     kfree(adapter->rx_ring);
 
     if (hw->mac_type == e1000_ce4100)
         iounmap(hw->ce4100_gbe_mdio_base_virt);
     iounmap(hw->hw_addr);
     if (hw->flash_address)
         iounmap(hw->flash_address);
     pci_release_selected_regions(pdev, adapter->bars);
 
     disable_dev = !test_and_set_bit(__E1000_DISABLED, &adapter->flags);
     free_netdev(netdev);
 
     if (disable_dev)
         pci_disable_device(pdev);
 }
 
 /**
  * e1000_sw_init - Initialize general software structures (struct e1000_adapter)
  * @adapter: board private structure to initialize
  *
  * e1000_sw_init initializes the Adapter private data structure.
  * e1000_init_hw_struct MUST be called before this function
  **/
 static int e1000_sw_init(struct e1000_adapter *adapter)
 {
     adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
 
     adapter->num_tx_queues = 1;
     adapter->num_rx_queues = 1;
 
     if (e1000_alloc_queues(adapter)) {
         e_err(probe, "Unable to allocate memory for queues\n");
         return -ENOMEM;
     }
 
     /* Explicitly disable IRQ since the NIC can be in any state. */
     e1000_irq_disable(adapter);
 
     spin_lock_init(&adapter->stats_lock);
 
     set_bit(__E1000_DOWN, &adapter->flags);
 
     return 0;
 }
 
 /**
  * e1000_alloc_queues - Allocate memory for all rings
  * @adapter: board private structure to initialize
  *
  * We allocate one ring per queue at run-time since we don't know the
  * number of queues at compile-time.
  **/
 static int e1000_alloc_queues(struct e1000_adapter *adapter)
 {
     adapter->tx_ring = kcalloc(adapter->num_tx_queues,
                    sizeof(struct e1000_tx_ring), GFP_KERNEL);
     if (!adapter->tx_ring)
         return -ENOMEM;
 
     adapter->rx_ring = kcalloc(adapter->num_rx_queues,
                    sizeof(struct e1000_rx_ring), GFP_KERNEL);
     if (!adapter->rx_ring) {
         kfree(adapter->tx_ring);
         return -ENOMEM;
     }
 
     return E1000_SUCCESS;
 }
 
 /**
  * e1000_open - Called when a network interface is made active
  * @netdev: network interface device structure
  *
  * Returns 0 on success, negative value on failure
  *
  * The open entry point is called when a network interface is made
  * active by the system (IFF_UP).  At this point all resources needed
  * for transmit and receive operations are allocated, the interrupt
  * handler is registered with the OS, the watchdog task is started,
  * and the stack is notified that the interface is ready.
  **/
 int e1000_open(struct net_device *netdev)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     int err;
 
     /* disallow open during test */
     if (test_bit(__E1000_TESTING, &adapter->flags))
         return -EBUSY;
 
     netif_carrier_off(netdev);
 
     /* allocate transmit descriptors */
     err = e1000_setup_all_tx_resources(adapter);
     if (err)
         goto err_setup_tx;
 
     /* allocate receive descriptors */
     err = e1000_setup_all_rx_resources(adapter);
     if (err)
         goto err_setup_rx;
 
     e1000_power_up_phy(adapter);
 
     adapter->mng_vlan_id = E1000_MNG_VLAN_NONE;
     if ((hw->mng_cookie.status &
               E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT)) {
         e1000_update_mng_vlan(adapter);
     }
 
     /* before we allocate an interrupt, we must be ready to handle it.
      * Setting DEBUG_SHIRQ in the kernel makes it fire an interrupt
      * as soon as we call pci_request_irq, so we have to setup our
      * clean_rx handler before we do so.
      */
     e1000_configure(adapter);
 
     err = e1000_request_irq(adapter);
     if (err)
         goto err_req_irq;
 
     /* From here on the code is the same as e1000_up() */
     clear_bit(__E1000_DOWN, &adapter->flags);
 
     napi_enable(&adapter->napi);
 
     e1000_irq_enable(adapter);
 
     netif_start_queue(netdev);
 
     /* fire a link status change interrupt to start the watchdog */
     ew32(ICS, E1000_ICS_LSC);
 
     return E1000_SUCCESS;
 
 err_req_irq:
     e1000_power_down_phy(adapter);
     e1000_free_all_rx_resources(adapter);
 err_setup_rx:
     e1000_free_all_tx_resources(adapter);
 err_setup_tx:
     e1000_reset(adapter);
 
     return err;
 }
 
 /**
  * e1000_close - Disables a network interface
  * @netdev: network interface device structure
  *
  * Returns 0, this is not allowed to fail
  *
  * The close entry point is called when an interface is de-activated
  * by the OS.  The hardware is still under the drivers control, but
  * needs to be disabled.  A global MAC reset is issued to stop the
  * hardware, and all transmit and receive resources are freed.
  **/
 int e1000_close(struct net_device *netdev)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     int count = E1000_CHECK_RESET_COUNT;
 
     while (test_and_set_bit(__E1000_RESETTING, &adapter->flags) && count--)
         usleep_range(10000, 20000);
 
     WARN_ON(count < 0);
 
     /* signal that we're down so that the reset task will no longer run */
     set_bit(__E1000_DOWN, &adapter->flags);
     clear_bit(__E1000_RESETTING, &adapter->flags);
 
     e1000_down(adapter);
     e1000_power_down_phy(adapter);
     e1000_free_irq(adapter);
 
     e1000_free_all_tx_resources(adapter);
     e1000_free_all_rx_resources(adapter);
 
     /* kill manageability vlan ID if supported, but not if a vlan with
      * the same ID is registered on the host OS (let 8021q kill it)
      */
     if ((hw->mng_cookie.status &
          E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT) &&
         !test_bit(adapter->mng_vlan_id, adapter->active_vlans)) {
         e1000_vlan_rx_kill_vid(netdev, htons(ETH_P_8021Q),
                        adapter->mng_vlan_id);
     }
 
     return 0;
 }
 
 /**
  * e1000_check_64k_bound - check that memory doesn't cross 64kB boundary
  * @adapter: address of board private structure
  * @start: address of beginning of memory
  * @len: length of memory
  **/
 static bool e1000_check_64k_bound(struct e1000_adapter *adapter, void *start,
                   unsigned long len)
 {
     struct e1000_hw *hw = &adapter->hw;
     unsigned long begin = (unsigned long)start;
     unsigned long end = begin + len;
 
     /* First rev 82545 and 82546 need to not allow any memory
      * write location to cross 64k boundary due to errata 23
      */
     if (hw->mac_type == e1000_82545 ||
         hw->mac_type == e1000_ce4100 ||
         hw->mac_type == e1000_82546) {
         return ((begin ^ (end - 1)) >> 16) == 0;
     }
 
     return true;
 }
 
 /**
  * e1000_setup_tx_resources - allocate Tx resources (Descriptors)
  * @adapter: board private structure
  * @txdr:    tx descriptor ring (for a specific queue) to setup
  *
  * Return 0 on success, negative on failure
  **/
 static int e1000_setup_tx_resources(struct e1000_adapter *adapter,
                     struct e1000_tx_ring *txdr)
 {
     struct pci_dev *pdev = adapter->pdev;
     int size;
 
     size = sizeof(struct e1000_tx_buffer) * txdr->count;
     txdr->buffer_info = vzalloc(size);
     if (!txdr->buffer_info)
         return -ENOMEM;
 
     /* round up to nearest 4K */
 
     txdr->size = txdr->count * sizeof(struct e1000_tx_desc);
     txdr->size = ALIGN(txdr->size, 4096);
 
     txdr->desc = dma_alloc_coherent(&pdev->dev, txdr->size, &txdr->dma,
                     GFP_KERNEL);
     if (!txdr->desc) {
 setup_tx_desc_die:
         vfree(txdr->buffer_info);
         return -ENOMEM;
     }
 
     /* Fix for errata 23, can't cross 64kB boundary */
     if (!e1000_check_64k_bound(adapter, txdr->desc, txdr->size)) {
         void *olddesc = txdr->desc;
         dma_addr_t olddma = txdr->dma;
         e_err(tx_err, "txdr align check failed: %u bytes at %p\n",
               txdr->size, txdr->desc);
         /* Try again, without freeing the previous */
         txdr->desc = dma_alloc_coherent(&pdev->dev, txdr->size,
                         &txdr->dma, GFP_KERNEL);
         /* Failed allocation, critical failure */
         if (!txdr->desc) {
             dma_free_coherent(&pdev->dev, txdr->size, olddesc,
                       olddma);
             goto setup_tx_desc_die;
         }
 
         if (!e1000_check_64k_bound(adapter, txdr->desc, txdr->size)) {
             /* give up */
             dma_free_coherent(&pdev->dev, txdr->size, txdr->desc,
                       txdr->dma);
             dma_free_coherent(&pdev->dev, txdr->size, olddesc,
                       olddma);
             e_err(probe, "Unable to allocate aligned memory "
                   "for the transmit descriptor ring\n");
             vfree(txdr->buffer_info);
             return -ENOMEM;
         } else {
             /* Free old allocation, new allocation was successful */
             dma_free_coherent(&pdev->dev, txdr->size, olddesc,
                       olddma);
         }
     }
     memset(txdr->desc, 0, txdr->size);
 
     txdr->next_to_use = 0;
     txdr->next_to_clean = 0;
 
     return 0;
 }
 
 /**
  * e1000_setup_all_tx_resources - wrapper to allocate Tx resources
  *                (Descriptors) for all queues
  * @adapter: board private structure
  *
  * Return 0 on success, negative on failure
  **/
 int e1000_setup_all_tx_resources(struct e1000_adapter *adapter)
 {
     int i, err = 0;
 
     for (i = 0; i < adapter->num_tx_queues; i++) {
         err = e1000_setup_tx_resources(adapter, &adapter->tx_ring[i]);
         if (err) {
             e_err(probe, "Allocation for Tx Queue %u failed\n", i);
             for (i-- ; i >= 0; i--)
                 e1000_free_tx_resources(adapter,
                             &adapter->tx_ring[i]);
             break;
         }
     }
 
     return err;
 }
 
 /**
  * e1000_configure_tx - Configure 8254x Transmit Unit after Reset
  * @adapter: board private structure
  *
  * Configure the Tx unit of the MAC after a reset.
  **/
 static void e1000_configure_tx(struct e1000_adapter *adapter)
 {
     u64 tdba;
     struct e1000_hw *hw = &adapter->hw;
     u32 tdlen, tctl, tipg;
     u32 ipgr1, ipgr2;
 
     /* Setup the HW Tx Head and Tail descriptor pointers */
 
     switch (adapter->num_tx_queues) {
     case 1:
     default:
         tdba = adapter->tx_ring[0].dma;
         tdlen = adapter->tx_ring[0].count *
             sizeof(struct e1000_tx_desc);
         ew32(TDLEN, tdlen);
         ew32(TDBAH, (tdba >> 32));
         ew32(TDBAL, (tdba & 0x00000000ffffffffULL));
         ew32(TDT, 0);
         ew32(TDH, 0);
         adapter->tx_ring[0].tdh = ((hw->mac_type >= e1000_82543) ?
                        E1000_TDH : E1000_82542_TDH);
         adapter->tx_ring[0].tdt = ((hw->mac_type >= e1000_82543) ?
                        E1000_TDT : E1000_82542_TDT);
         break;
     }
 
     /* Set the default values for the Tx Inter Packet Gap timer */
     if ((hw->media_type == e1000_media_type_fiber ||
          hw->media_type == e1000_media_type_internal_serdes))
         tipg = DEFAULT_82543_TIPG_IPGT_FIBER;
     else
         tipg = DEFAULT_82543_TIPG_IPGT_COPPER;
 
     switch (hw->mac_type) {
     case e1000_82542_rev2_0:
     case e1000_82542_rev2_1:
         tipg = DEFAULT_82542_TIPG_IPGT;
         ipgr1 = DEFAULT_82542_TIPG_IPGR1;
         ipgr2 = DEFAULT_82542_TIPG_IPGR2;
         break;
     default:
         ipgr1 = DEFAULT_82543_TIPG_IPGR1;
         ipgr2 = DEFAULT_82543_TIPG_IPGR2;
         break;
     }
     tipg |= ipgr1 << E1000_TIPG_IPGR1_SHIFT;
     tipg |= ipgr2 << E1000_TIPG_IPGR2_SHIFT;
     ew32(TIPG, tipg);
 
     /* Set the Tx Interrupt Delay register */
 
     ew32(TIDV, adapter->tx_int_delay);
     if (hw->mac_type >= e1000_82540)
         ew32(TADV, adapter->tx_abs_int_delay);
 
     /* Program the Transmit Control Register */
 
     tctl = er32(TCTL);
     tctl &= ~E1000_TCTL_CT;
     tctl |= E1000_TCTL_PSP | E1000_TCTL_RTLC |
         (E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT);
 
     e1000_config_collision_dist(hw);
 
     /* Setup Transmit Descriptor Settings for eop descriptor */
     adapter->txd_cmd = E1000_TXD_CMD_EOP | E1000_TXD_CMD_IFCS;
 
     /* only set IDE if we are delaying interrupts using the timers */
     if (adapter->tx_int_delay)
         adapter->txd_cmd |= E1000_TXD_CMD_IDE;
 
     if (hw->mac_type < e1000_82543)
         adapter->txd_cmd |= E1000_TXD_CMD_RPS;
     else
         adapter->txd_cmd |= E1000_TXD_CMD_RS;
 
     /* Cache if we're 82544 running in PCI-X because we'll
      * need this to apply a workaround later in the send path.
      */
     if (hw->mac_type == e1000_82544 &&
         hw->bus_type == e1000_bus_type_pcix)
         adapter->pcix_82544 = true;
 
     ew32(TCTL, tctl);
 
 }
 
 /**
  * e1000_setup_rx_resources - allocate Rx resources (Descriptors)
  * @adapter: board private structure
  * @rxdr:    rx descriptor ring (for a specific queue) to setup
  *
  * Returns 0 on success, negative on failure
  **/
 static int e1000_setup_rx_resources(struct e1000_adapter *adapter,
                     struct e1000_rx_ring *rxdr)
 {
     struct pci_dev *pdev = adapter->pdev;
     int size, desc_len;
 
     size = sizeof(struct e1000_rx_buffer) * rxdr->count;
     rxdr->buffer_info = vzalloc(size);
     if (!rxdr->buffer_info)
         return -ENOMEM;
 
     desc_len = sizeof(struct e1000_rx_desc);
 
     /* Round up to nearest 4K */
 
     rxdr->size = rxdr->count * desc_len;
     rxdr->size = ALIGN(rxdr->size, 4096);
 
     rxdr->desc = dma_alloc_coherent(&pdev->dev, rxdr->size, &rxdr->dma,
                     GFP_KERNEL);
     if (!rxdr->desc) {
 setup_rx_desc_die:
         vfree(rxdr->buffer_info);
         return -ENOMEM;
     }
 
     /* Fix for errata 23, can't cross 64kB boundary */
     if (!e1000_check_64k_bound(adapter, rxdr->desc, rxdr->size)) {
         void *olddesc = rxdr->desc;
         dma_addr_t olddma = rxdr->dma;
         e_err(rx_err, "rxdr align check failed: %u bytes at %p\n",
               rxdr->size, rxdr->desc);
         /* Try again, without freeing the previous */
         rxdr->desc = dma_alloc_coherent(&pdev->dev, rxdr->size,
                         &rxdr->dma, GFP_KERNEL);
         /* Failed allocation, critical failure */
         if (!rxdr->desc) {
             dma_free_coherent(&pdev->dev, rxdr->size, olddesc,
                       olddma);
             goto setup_rx_desc_die;
         }
 
         if (!e1000_check_64k_bound(adapter, rxdr->desc, rxdr->size)) {
             /* give up */
             dma_free_coherent(&pdev->dev, rxdr->size, rxdr->desc,
                       rxdr->dma);
             dma_free_coherent(&pdev->dev, rxdr->size, olddesc,
                       olddma);
             e_err(probe, "Unable to allocate aligned memory for "
                   "the Rx descriptor ring\n");
             goto setup_rx_desc_die;
         } else {
             /* Free old allocation, new allocation was successful */
             dma_free_coherent(&pdev->dev, rxdr->size, olddesc,
                       olddma);
         }
     }
     memset(rxdr->desc, 0, rxdr->size);
 
     rxdr->next_to_clean = 0;
     rxdr->next_to_use = 0;
     rxdr->rx_skb_top = NULL;
 
     return 0;
 }
 
 /**
  * e1000_setup_all_rx_resources - wrapper to allocate Rx resources
  *                (Descriptors) for all queues
  * @adapter: board private structure
  *
  * Return 0 on success, negative on failure
  **/
 int e1000_setup_all_rx_resources(struct e1000_adapter *adapter)
 {
     int i, err = 0;
 
     for (i = 0; i < adapter->num_rx_queues; i++) {
         err = e1000_setup_rx_resources(adapter, &adapter->rx_ring[i]);
         if (err) {
             e_err(probe, "Allocation for Rx Queue %u failed\n", i);
             for (i-- ; i >= 0; i--)
                 e1000_free_rx_resources(adapter,
                             &adapter->rx_ring[i]);
             break;
         }
     }
 
     return err;
 }
 
 /**
  * e1000_setup_rctl - configure the receive control registers
  * @adapter: Board private structure
  **/
 static void e1000_setup_rctl(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     u32 rctl;
 
     rctl = er32(RCTL);
 
     rctl &= ~(3 << E1000_RCTL_MO_SHIFT);
 
     rctl |= E1000_RCTL_BAM | E1000_RCTL_LBM_NO |
         E1000_RCTL_RDMTS_HALF |
         (hw->mc_filter_type << E1000_RCTL_MO_SHIFT);
 
     if (hw->tbi_compatibility_on == 1)
         rctl |= E1000_RCTL_SBP;
     else
         rctl &= ~E1000_RCTL_SBP;
 
     if (adapter->netdev->mtu <= ETH_DATA_LEN)
         rctl &= ~E1000_RCTL_LPE;
     else
         rctl |= E1000_RCTL_LPE;
 
     /* Setup buffer sizes */
     rctl &= ~E1000_RCTL_SZ_4096;
     rctl |= E1000_RCTL_BSEX;
     switch (adapter->rx_buffer_len) {
     case E1000_RXBUFFER_2048:
     default:
         rctl |= E1000_RCTL_SZ_2048;
         rctl &= ~E1000_RCTL_BSEX;
         break;
     case E1000_RXBUFFER_4096:
         rctl |= E1000_RCTL_SZ_4096;
         break;
     case E1000_RXBUFFER_8192:
         rctl |= E1000_RCTL_SZ_8192;
         break;
     case E1000_RXBUFFER_16384:
         rctl |= E1000_RCTL_SZ_16384;
         break;
     }
 
     /* This is useful for sniffing bad packets. */
     if (adapter->netdev->features & NETIF_F_RXALL) {
         /* UPE and MPE will be handled by normal PROMISC logic
          * in e1000e_set_rx_mode
          */
         rctl |= (E1000_RCTL_SBP | /* Receive bad packets */
              E1000_RCTL_BAM | /* RX All Bcast Pkts */
              E1000_RCTL_PMCF); /* RX All MAC Ctrl Pkts */
 
         rctl &= ~(E1000_RCTL_VFE | /* Disable VLAN filter */
               E1000_RCTL_DPF | /* Allow filtered pause */
               E1000_RCTL_CFIEN); /* Dis VLAN CFIEN Filter */
         /* Do not mess with E1000_CTRL_VME, it affects transmit as well,
          * and that breaks VLANs.
          */
     }
 
     ew32(RCTL, rctl);
 }
 
 /**
  * e1000_configure_rx - Configure 8254x Receive Unit after Reset
  * @adapter: board private structure
  *
  * Configure the Rx unit of the MAC after a reset.
  **/
 static void e1000_configure_rx(struct e1000_adapter *adapter)
 {
     u64 rdba;
     struct e1000_hw *hw = &adapter->hw;
     u32 rdlen, rctl, rxcsum;
 
     if (adapter->netdev->mtu > ETH_DATA_LEN) {
         rdlen = adapter->rx_ring[0].count *
             sizeof(struct e1000_rx_desc);
         adapter->clean_rx = e1000_clean_jumbo_rx_irq;
         adapter->alloc_rx_buf = e1000_alloc_jumbo_rx_buffers;
     } else {
         rdlen = adapter->rx_ring[0].count *
             sizeof(struct e1000_rx_desc);
         adapter->clean_rx = e1000_clean_rx_irq;
         adapter->alloc_rx_buf = e1000_alloc_rx_buffers;
     }
 
     /* disable receives while setting up the descriptors */
     rctl = er32(RCTL);
     ew32(RCTL, rctl & ~E1000_RCTL_EN);
 
     /* set the Receive Delay Timer Register */
     ew32(RDTR, adapter->rx_int_delay);
 
     if (hw->mac_type >= e1000_82540) {
         ew32(RADV, adapter->rx_abs_int_delay);
         if (adapter->itr_setting != 0)
             ew32(ITR, 1000000000 / (adapter->itr * 256));
     }
 
     /* Setup the HW Rx Head and Tail Descriptor Pointers and
      * the Base and Length of the Rx Descriptor Ring
      */
     switch (adapter->num_rx_queues) {
     case 1:
     default:
         rdba = adapter->rx_ring[0].dma;
         ew32(RDLEN, rdlen);
         ew32(RDBAH, (rdba >> 32));
         ew32(RDBAL, (rdba & 0x00000000ffffffffULL));
         ew32(RDT, 0);
         ew32(RDH, 0);
         adapter->rx_ring[0].rdh = ((hw->mac_type >= e1000_82543) ?
                        E1000_RDH : E1000_82542_RDH);
         adapter->rx_ring[0].rdt = ((hw->mac_type >= e1000_82543) ?
                        E1000_RDT : E1000_82542_RDT);
         break;
     }
 
     /* Enable 82543 Receive Checksum Offload for TCP and UDP */
     if (hw->mac_type >= e1000_82543) {
         rxcsum = er32(RXCSUM);
         if (adapter->rx_csum)
             rxcsum |= E1000_RXCSUM_TUOFL;
         else
             /* don't need to clear IPPCSE as it defaults to 0 */
             rxcsum &= ~E1000_RXCSUM_TUOFL;
         ew32(RXCSUM, rxcsum);
     }
 
     /* Enable Receives */
     ew32(RCTL, rctl | E1000_RCTL_EN);
 }
 
 /**
  * e1000_free_tx_resources - Free Tx Resources per Queue
  * @adapter: board private structure
  * @tx_ring: Tx descriptor ring for a specific queue
  *
  * Free all transmit software resources
  **/
 static void e1000_free_tx_resources(struct e1000_adapter *adapter,
                     struct e1000_tx_ring *tx_ring)
 {
     struct pci_dev *pdev = adapter->pdev;
 
     e1000_clean_tx_ring(adapter, tx_ring);
 
     vfree(tx_ring->buffer_info);
     tx_ring->buffer_info = NULL;
 
     dma_free_coherent(&pdev->dev, tx_ring->size, tx_ring->desc,
               tx_ring->dma);
 
     tx_ring->desc = NULL;
 }
 
 /**
  * e1000_free_all_tx_resources - Free Tx Resources for All Queues
  * @adapter: board private structure
  *
  * Free all transmit software resources
  **/
 void e1000_free_all_tx_resources(struct e1000_adapter *adapter)
 {
     int i;
 
     for (i = 0; i < adapter->num_tx_queues; i++)
         e1000_free_tx_resources(adapter, &adapter->tx_ring[i]);
 }
 
 static void
 e1000_unmap_and_free_tx_resource(struct e1000_adapter *adapter,
                  struct e1000_tx_buffer *buffer_info,
                  int budget)
 {
     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) {
         napi_consume_skb(buffer_info->skb, budget);
         buffer_info->skb = NULL;
     }
     buffer_info->time_stamp = 0;
     /* buffer_info must be completely set up in the transmit path */
 }
 
 /**
  * e1000_clean_tx_ring - Free Tx Buffers
  * @adapter: board private structure
  * @tx_ring: ring to be cleaned
  **/
 static void e1000_clean_tx_ring(struct e1000_adapter *adapter,
                 struct e1000_tx_ring *tx_ring)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct e1000_tx_buffer *buffer_info;
     unsigned long size;
     unsigned int i;
 
     /* Free all the Tx ring sk_buffs */
 
     for (i = 0; i < tx_ring->count; i++) {
         buffer_info = &tx_ring->buffer_info[i];
         e1000_unmap_and_free_tx_resource(adapter, buffer_info, 0);
     }
 
     netdev_reset_queue(adapter->netdev);
     size = sizeof(struct e1000_tx_buffer) * tx_ring->count;
     memset(tx_ring->buffer_info, 0, size);
 
     /* Zero out the descriptor ring */
 
     memset(tx_ring->desc, 0, tx_ring->size);
 
     tx_ring->next_to_use = 0;
     tx_ring->next_to_clean = 0;
     tx_ring->last_tx_tso = false;
 
     writel(0, hw->hw_addr + tx_ring->tdh);
     writel(0, hw->hw_addr + tx_ring->tdt);
 }
 
 /**
  * e1000_clean_all_tx_rings - Free Tx Buffers for all queues
  * @adapter: board private structure
  **/
 static void e1000_clean_all_tx_rings(struct e1000_adapter *adapter)
 {
     int i;
 
     for (i = 0; i < adapter->num_tx_queues; i++)
         e1000_clean_tx_ring(adapter, &adapter->tx_ring[i]);
 }
 
 /**
  * e1000_free_rx_resources - Free Rx Resources
  * @adapter: board private structure
  * @rx_ring: ring to clean the resources from
  *
  * Free all receive software resources
  **/
 static void e1000_free_rx_resources(struct e1000_adapter *adapter,
                     struct e1000_rx_ring *rx_ring)
 {
     struct pci_dev *pdev = adapter->pdev;
 
     e1000_clean_rx_ring(adapter, rx_ring);
 
     vfree(rx_ring->buffer_info);
     rx_ring->buffer_info = NULL;
 
     dma_free_coherent(&pdev->dev, rx_ring->size, rx_ring->desc,
               rx_ring->dma);
 
     rx_ring->desc = NULL;
 }
 
 /**
  * e1000_free_all_rx_resources - Free Rx Resources for All Queues
  * @adapter: board private structure
  *
  * Free all receive software resources
  **/
 void e1000_free_all_rx_resources(struct e1000_adapter *adapter)
 {
     int i;
 
     for (i = 0; i < adapter->num_rx_queues; i++)
         e1000_free_rx_resources(adapter, &adapter->rx_ring[i]);
 }
 
 #define E1000_HEADROOM (NET_SKB_PAD + NET_IP_ALIGN)
 static unsigned int e1000_frag_len(const struct e1000_adapter *a)
 {
     return SKB_DATA_ALIGN(a->rx_buffer_len + E1000_HEADROOM) +
         SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 }
 
 static void *e1000_alloc_frag(const struct e1000_adapter *a)
 {
     unsigned int len = e1000_frag_len(a);
     u8 *data = netdev_alloc_frag(len);
 
     if (likely(data))
         data += E1000_HEADROOM;
     return data;
 }
 
 /**
  * e1000_clean_rx_ring - Free Rx Buffers per Queue
  * @adapter: board private structure
  * @rx_ring: ring to free buffers from
  **/
 static void e1000_clean_rx_ring(struct e1000_adapter *adapter,
                 struct e1000_rx_ring *rx_ring)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct e1000_rx_buffer *buffer_info;
     struct pci_dev *pdev = adapter->pdev;
     unsigned long size;
     unsigned int i;
 
     /* Free all the Rx netfrags */
     for (i = 0; i < rx_ring->count; i++) {
         buffer_info = &rx_ring->buffer_info[i];
         if (adapter->clean_rx == e1000_clean_rx_irq) {
             if (buffer_info->dma)
                 dma_unmap_single(&pdev->dev, buffer_info->dma,
                          adapter->rx_buffer_len,
                          DMA_FROM_DEVICE);
             if (buffer_info->rxbuf.data) {
                 skb_free_frag(buffer_info->rxbuf.data);
                 buffer_info->rxbuf.data = NULL;
             }
         } else if (adapter->clean_rx == e1000_clean_jumbo_rx_irq) {
             if (buffer_info->dma)
                 dma_unmap_page(&pdev->dev, buffer_info->dma,
                            adapter->rx_buffer_len,
                            DMA_FROM_DEVICE);
             if (buffer_info->rxbuf.page) {
                 put_page(buffer_info->rxbuf.page);
                 buffer_info->rxbuf.page = NULL;
             }
         }
 
         buffer_info->dma = 0;
     }
 
     /* there also may be some cached data from a chained receive */
     napi_free_frags(&adapter->napi);
     rx_ring->rx_skb_top = NULL;
 
     size = sizeof(struct e1000_rx_buffer) * rx_ring->count;
     memset(rx_ring->buffer_info, 0, size);
 
     /* Zero out the descriptor ring */
     memset(rx_ring->desc, 0, rx_ring->size);
 
     rx_ring->next_to_clean = 0;
     rx_ring->next_to_use = 0;
 
     writel(0, hw->hw_addr + rx_ring->rdh);
     writel(0, hw->hw_addr + rx_ring->rdt);
 }
 
 /**
  * e1000_clean_all_rx_rings - Free Rx Buffers for all queues
  * @adapter: board private structure
  **/
 static void e1000_clean_all_rx_rings(struct e1000_adapter *adapter)
 {
     int i;
 
     for (i = 0; i < adapter->num_rx_queues; i++)
         e1000_clean_rx_ring(adapter, &adapter->rx_ring[i]);
 }
 
 /* The 82542 2.0 (revision 2) needs to have the receive unit in reset
  * and memory write and invalidate disabled for certain operations
  */
 static void e1000_enter_82542_rst(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     u32 rctl;
 
     e1000_pci_clear_mwi(hw);
 
     rctl = er32(RCTL);
     rctl |= E1000_RCTL_RST;
     ew32(RCTL, rctl);
     E1000_WRITE_FLUSH();
     mdelay(5);
 
     if (netif_running(netdev))
         e1000_clean_all_rx_rings(adapter);
 }
 
 static void e1000_leave_82542_rst(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     u32 rctl;
 
     rctl = er32(RCTL);
     rctl &= ~E1000_RCTL_RST;
     ew32(RCTL, rctl);
     E1000_WRITE_FLUSH();
     mdelay(5);
 
     if (hw->pci_cmd_word & PCI_COMMAND_INVALIDATE)
         e1000_pci_set_mwi(hw);
 
     if (netif_running(netdev)) {
         /* No need to loop, because 82542 supports only 1 queue */
         struct e1000_rx_ring *ring = &adapter->rx_ring[0];
         e1000_configure_rx(adapter);
         adapter->alloc_rx_buf(adapter, ring, E1000_DESC_UNUSED(ring));
     }
 }
 
 /**
  * e1000_set_mac - Change the Ethernet Address of the NIC
  * @netdev: network interface device structure
  * @p: pointer to an address structure
  *
  * Returns 0 on success, negative on failure
  **/
 static int e1000_set_mac(struct net_device *netdev, void *p)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     struct sockaddr *addr = p;
 
     if (!is_valid_ether_addr(addr->sa_data))
         return -EADDRNOTAVAIL;
 
     /* 82542 2.0 needs to be in reset to write receive address registers */
 
     if (hw->mac_type == e1000_82542_rev2_0)
         e1000_enter_82542_rst(adapter);
 
     eth_hw_addr_set(netdev, addr->sa_data);
     memcpy(hw->mac_addr, addr->sa_data, netdev->addr_len);
 
     e1000_rar_set(hw, hw->mac_addr, 0);
 
     if (hw->mac_type == e1000_82542_rev2_0)
         e1000_leave_82542_rst(adapter);
 
     return 0;
 }
 
 /**
  * e1000_set_rx_mode - Secondary Unicast, Multicast and Promiscuous mode set
  * @netdev: network interface device structure
  *
  * The set_rx_mode entry point is called whenever the unicast or multicast
  * address lists or the network interface flags are updated. This routine is
  * responsible for configuring the hardware for proper unicast, multicast,
  * promiscuous mode, and all-multi behavior.
  **/
 static void e1000_set_rx_mode(struct net_device *netdev)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     struct netdev_hw_addr *ha;
     bool use_uc = false;
     u32 rctl;
     u32 hash_value;
     int i, rar_entries = E1000_RAR_ENTRIES;
     int mta_reg_count = E1000_NUM_MTA_REGISTERS;
     u32 *mcarray = kcalloc(mta_reg_count, sizeof(u32), GFP_ATOMIC);
 
     if (!mcarray)
         return;
 
     /* Check for Promiscuous and All Multicast modes */
 
     rctl = er32(RCTL);
 
     if (netdev->flags & IFF_PROMISC) {
         rctl |= (E1000_RCTL_UPE | E1000_RCTL_MPE);
         rctl &= ~E1000_RCTL_VFE;
     } else {
         if (netdev->flags & IFF_ALLMULTI)
             rctl |= E1000_RCTL_MPE;
         else
             rctl &= ~E1000_RCTL_MPE;
         /* Enable VLAN filter if there is a VLAN */
         if (e1000_vlan_used(adapter))
             rctl |= E1000_RCTL_VFE;
     }
 
     if (netdev_uc_count(netdev) > rar_entries - 1) {
         rctl |= E1000_RCTL_UPE;
     } else if (!(netdev->flags & IFF_PROMISC)) {
         rctl &= ~E1000_RCTL_UPE;
         use_uc = true;
     }
 
     ew32(RCTL, rctl);
 
     /* 82542 2.0 needs to be in reset to write receive address registers */
 
     if (hw->mac_type == e1000_82542_rev2_0)
         e1000_enter_82542_rst(adapter);
 
     /* load the first 14 addresses into the exact filters 1-14. Unicast
      * addresses take precedence to avoid disabling unicast filtering
      * when possible.
      *
      * RAR 0 is used for the station MAC address
      * if there are not 14 addresses, go ahead and clear the filters
      */
     i = 1;
     if (use_uc)
         netdev_for_each_uc_addr(ha, netdev) {
             if (i == rar_entries)
                 break;
             e1000_rar_set(hw, ha->addr, i++);
         }
 
     netdev_for_each_mc_addr(ha, netdev) {
         if (i == rar_entries) {
             /* load any remaining addresses into the hash table */
             u32 hash_reg, hash_bit, mta;
             hash_value = e1000_hash_mc_addr(hw, ha->addr);
             hash_reg = (hash_value >> 5) & 0x7F;
             hash_bit = hash_value & 0x1F;
             mta = (1 << hash_bit);
             mcarray[hash_reg] |= mta;
         } else {
             e1000_rar_set(hw, ha->addr, i++);
         }
     }
 
     for (; i < rar_entries; i++) {
         E1000_WRITE_REG_ARRAY(hw, RA, i << 1, 0);
         E1000_WRITE_FLUSH();
         E1000_WRITE_REG_ARRAY(hw, RA, (i << 1) + 1, 0);
         E1000_WRITE_FLUSH();
     }
 
     /* write the hash table completely, write from bottom to avoid
      * both stupid write combining chipsets, and flushing each write
      */
     for (i = mta_reg_count - 1; i >= 0 ; i--) {
         /* If we are on an 82544 has an errata where writing odd
          * offsets overwrites the previous even offset, but writing
          * backwards over the range solves the issue by always
          * writing the odd offset first
          */
         E1000_WRITE_REG_ARRAY(hw, MTA, i, mcarray[i]);
     }
     E1000_WRITE_FLUSH();
 
     if (hw->mac_type == e1000_82542_rev2_0)
         e1000_leave_82542_rst(adapter);
 
     kfree(mcarray);
 }
 
 /**
  * e1000_update_phy_info_task - get phy info
  * @work: work struct contained inside adapter struct
  *
  * Need to wait a few seconds after link up to get diagnostic information from
  * the phy
  */
 static void e1000_update_phy_info_task(struct work_struct *work)
 {
     struct e1000_adapter *adapter = container_of(work,
                              struct e1000_adapter,
                              phy_info_task.work);
 
     e1000_phy_get_info(&adapter->hw, &adapter->phy_info);
 }
 
 /**
  * e1000_82547_tx_fifo_stall_task - task to complete work
  * @work: work struct contained inside adapter struct
  **/
 static void e1000_82547_tx_fifo_stall_task(struct work_struct *work)
 {
     struct e1000_adapter *adapter = container_of(work,
                              struct e1000_adapter,
                              fifo_stall_task.work);
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     u32 tctl;
 
     if (atomic_read(&adapter->tx_fifo_stall)) {
         if ((er32(TDT) == er32(TDH)) &&
            (er32(TDFT) == er32(TDFH)) &&
            (er32(TDFTS) == er32(TDFHS))) {
             tctl = er32(TCTL);
             ew32(TCTL, tctl & ~E1000_TCTL_EN);
             ew32(TDFT, adapter->tx_head_addr);
             ew32(TDFH, adapter->tx_head_addr);
             ew32(TDFTS, adapter->tx_head_addr);
             ew32(TDFHS, adapter->tx_head_addr);
             ew32(TCTL, tctl);
             E1000_WRITE_FLUSH();
 
             adapter->tx_fifo_head = 0;
             atomic_set(&adapter->tx_fifo_stall, 0);
             netif_wake_queue(netdev);
         } else if (!test_bit(__E1000_DOWN, &adapter->flags)) {
             schedule_delayed_work(&adapter->fifo_stall_task, 1);
         }
     }
 }
 
 bool e1000_has_link(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     bool link_active = false;
 
     /* get_link_status is set on LSC (link status) interrupt or rx
      * sequence error interrupt (except on intel ce4100).
      * get_link_status will stay false until the
      * e1000_check_for_link establishes link for copper adapters
      * ONLY
      */
     switch (hw->media_type) {
     case e1000_media_type_copper:
         if (hw->mac_type == e1000_ce4100)
             hw->get_link_status = 1;
         if (hw->get_link_status) {
             e1000_check_for_link(hw);
             link_active = !hw->get_link_status;
         } else {
             link_active = true;
         }
         break;
     case e1000_media_type_fiber:
         e1000_check_for_link(hw);
         link_active = !!(er32(STATUS) & E1000_STATUS_LU);
         break;
     case e1000_media_type_internal_serdes:
         e1000_check_for_link(hw);
         link_active = hw->serdes_has_link;
         break;
     default:
         break;
     }
 
     return link_active;
 }
 
 /**
  * e1000_watchdog - work function
  * @work: work struct contained inside adapter struct
  **/
 static void e1000_watchdog(struct work_struct *work)
 {
     struct e1000_adapter *adapter = container_of(work,
                              struct e1000_adapter,
                              watchdog_task.work);
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     struct e1000_tx_ring *txdr = adapter->tx_ring;
     u32 link, tctl;
 
     link = e1000_has_link(adapter);
     if ((netif_carrier_ok(netdev)) && link)
         goto link_up;
 
     if (link) {
         if (!netif_carrier_ok(netdev)) {
             u32 ctrl;
             /* update snapshot of PHY registers on LSC */
             e1000_get_speed_and_duplex(hw,
                            &adapter->link_speed,
                            &adapter->link_duplex);
 
             ctrl = er32(CTRL);
             pr_info("%s NIC Link is Up %d Mbps %s, "
                 "Flow Control: %s\n",
                 netdev->name,
                 adapter->link_speed,
                 adapter->link_duplex == FULL_DUPLEX ?
                 "Full Duplex" : "Half Duplex",
                 ((ctrl & E1000_CTRL_TFCE) && (ctrl &
                 E1000_CTRL_RFCE)) ? "RX/TX" : ((ctrl &
                 E1000_CTRL_RFCE) ? "RX" : ((ctrl &
                 E1000_CTRL_TFCE) ? "TX" : "None")));
 
             /* adjust timeout factor according to speed/duplex */
             adapter->tx_timeout_factor = 1;
             switch (adapter->link_speed) {
             case SPEED_10:
                 adapter->tx_timeout_factor = 16;
                 break;
             case SPEED_100:
                 /* maybe add some timeout factor ? */
                 break;
             }
 
             /* enable transmits in the hardware */
             tctl = er32(TCTL);
             tctl |= E1000_TCTL_EN;
             ew32(TCTL, tctl);
 
             netif_carrier_on(netdev);
             if (!test_bit(__E1000_DOWN, &adapter->flags))
                 schedule_delayed_work(&adapter->phy_info_task,
                               2 * HZ);
             adapter->smartspeed = 0;
         }
     } else {
         if (netif_carrier_ok(netdev)) {
             adapter->link_speed = 0;
             adapter->link_duplex = 0;
             pr_info("%s NIC Link is Down\n",
                 netdev->name);
             netif_carrier_off(netdev);
 
             if (!test_bit(__E1000_DOWN, &adapter->flags))
                 schedule_delayed_work(&adapter->phy_info_task,
                               2 * HZ);
         }
 
         e1000_smartspeed(adapter);
     }
 
 link_up:
     e1000_update_stats(adapter);
 
     hw->tx_packet_delta = adapter->stats.tpt - adapter->tpt_old;
     adapter->tpt_old = adapter->stats.tpt;
     hw->collision_delta = adapter->stats.colc - adapter->colc_old;
     adapter->colc_old = adapter->stats.colc;
 
     adapter->gorcl = adapter->stats.gorcl - adapter->gorcl_old;
     adapter->gorcl_old = adapter->stats.gorcl;
     adapter->gotcl = adapter->stats.gotcl - adapter->gotcl_old;
     adapter->gotcl_old = adapter->stats.gotcl;
 
     e1000_update_adaptive(hw);
 
     if (!netif_carrier_ok(netdev)) {
         if (E1000_DESC_UNUSED(txdr) + 1 < txdr->count) {
             /* We've lost link, so the controller stops DMA,
              * but we've got queued Tx work that's never going
              * to get done, so reset controller to flush Tx.
              * (Do the reset outside of interrupt context).
              */
             adapter->tx_timeout_count++;
             schedule_work(&adapter->reset_task);
             /* exit immediately since reset is imminent */
             return;
         }
     }
 
     /* Simple mode for Interrupt Throttle Rate (ITR) */
     if (hw->mac_type >= e1000_82540 && adapter->itr_setting == 4) {
         /* Symmetric Tx/Rx gets a reduced ITR=2000;
          * Total asymmetrical Tx or Rx gets ITR=8000;
          * everyone else is between 2000-8000.
          */
         u32 goc = (adapter->gotcl + adapter->gorcl) / 10000;
         u32 dif = (adapter->gotcl > adapter->gorcl ?
                 adapter->gotcl - adapter->gorcl :
                 adapter->gorcl - adapter->gotcl) / 10000;
         u32 itr = goc > 0 ? (dif * 6000 / goc + 2000) : 8000;
 
         ew32(ITR, 1000000000 / (itr * 256));
     }
 
     /* Cause software interrupt to ensure rx ring is cleaned */
     ew32(ICS, E1000_ICS_RXDMT0);
 
     /* Force detection of hung controller every watchdog period */
     adapter->detect_tx_hung = true;
 
     /* Reschedule the task */
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         schedule_delayed_work(&adapter->watchdog_task, 2 * HZ);
 }
 
 enum latency_range {
     lowest_latency = 0,
     low_latency = 1,
     bulk_latency = 2,
     latency_invalid = 255
 };
 
 /**
  * e1000_update_itr - update the dynamic ITR value based on statistics
  * @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 (see e1000_param.c)
  **/
 static unsigned int e1000_update_itr(struct e1000_adapter *adapter,
                      u16 itr_setting, int packets, int bytes)
 {
     unsigned int retval = itr_setting;
     struct e1000_hw *hw = &adapter->hw;
 
     if (unlikely(hw->mac_type < e1000_82540))
         goto update_itr_done;
 
     if (packets == 0)
         goto update_itr_done;
 
     switch (itr_setting) {
     case lowest_latency:
         /* jumbo frames get bulk treatment*/
         if (bytes/packets > 8000)
             retval = bulk_latency;
         else if ((packets < 5) && (bytes > 512))
             retval = low_latency;
         break;
     case low_latency:  /* 50 usec aka 20000 ints/s */
         if (bytes > 10000) {
             /* jumbo frames need bulk latency setting */
             if (bytes/packets > 8000)
                 retval = bulk_latency;
             else if ((packets < 10) || ((bytes/packets) > 1200))
                 retval = bulk_latency;
             else if ((packets > 35))
                 retval = lowest_latency;
         } else if (bytes/packets > 2000)
             retval = bulk_latency;
         else if (packets <= 2 && bytes < 512)
             retval = lowest_latency;
         break;
     case bulk_latency: /* 250 usec aka 4000 ints/s */
         if (bytes > 25000) {
             if (packets > 35)
                 retval = low_latency;
         } else if (bytes < 6000) {
             retval = low_latency;
         }
         break;
     }
 
 update_itr_done:
     return retval;
 }
 
 static void e1000_set_itr(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     u16 current_itr;
     u32 new_itr = adapter->itr;
 
     if (unlikely(hw->mac_type < e1000_82540))
         return;
 
     /* for non-gigabit speeds, just fix the interrupt rate at 4000 */
     if (unlikely(adapter->link_speed != SPEED_1000)) {
         new_itr = 4000;
         goto set_itr_now;
     }
 
     adapter->tx_itr = e1000_update_itr(adapter, adapter->tx_itr,
                        adapter->total_tx_packets,
                        adapter->total_tx_bytes);
     /* conservative mode (itr 3) eliminates the lowest_latency setting */
     if (adapter->itr_setting == 3 && adapter->tx_itr == lowest_latency)
         adapter->tx_itr = low_latency;
 
     adapter->rx_itr = e1000_update_itr(adapter, adapter->rx_itr,
                        adapter->total_rx_packets,
                        adapter->total_rx_bytes);
     /* conservative mode (itr 3) eliminates the lowest_latency setting */
     if (adapter->itr_setting == 3 && adapter->rx_itr == lowest_latency)
         adapter->rx_itr = low_latency;
 
     current_itr = max(adapter->rx_itr, adapter->tx_itr);
 
     switch (current_itr) {
     /* counts and packets in update_itr are dependent on these numbers */
     case lowest_latency:
         new_itr = 70000;
         break;
     case low_latency:
         new_itr = 20000; /* aka hwitr = ~200 */
         break;
     case bulk_latency:
         new_itr = 4000;
         break;
     default:
         break;
     }
 
 set_itr_now:
     if (new_itr != adapter->itr) {
         /* this attempts to bias the interrupt rate towards Bulk
          * by adding intermediate steps when interrupt rate is
          * increasing
          */
         new_itr = new_itr > adapter->itr ?
               min(adapter->itr + (new_itr >> 2), new_itr) :
               new_itr;
         adapter->itr = new_itr;
         ew32(ITR, 1000000000 / (new_itr * 256));
     }
 }
 
 #define E1000_TX_FLAGS_CSUM     0x00000001
 #define E1000_TX_FLAGS_VLAN     0x00000002
 #define E1000_TX_FLAGS_TSO      0x00000004
 #define E1000_TX_FLAGS_IPV4     0x00000008
 #define E1000_TX_FLAGS_NO_FCS       0x00000010
 #define E1000_TX_FLAGS_VLAN_MASK    0xffff0000
 #define E1000_TX_FLAGS_VLAN_SHIFT   16
 
 static int e1000_tso(struct e1000_adapter *adapter,
              struct e1000_tx_ring *tx_ring, struct sk_buff *skb,
              __be16 protocol)
 {
     struct e1000_context_desc *context_desc;
     struct e1000_tx_buffer *buffer_info;
     unsigned int i;
     u32 cmd_length = 0;
     u16 ipcse = 0, tucse, mss;
     u8 ipcss, ipcso, tucss, tucso, hdr_len;
 
     if (skb_is_gso(skb)) {
         int err;
 
         err = skb_cow_head(skb, 0);
         if (err < 0)
             return err;
 
         hdr_len = skb_tcp_all_headers(skb);
         mss = skb_shinfo(skb)->gso_size;
         if (protocol == htons(ETH_P_IP)) {
             struct iphdr *iph = ip_hdr(skb);
             iph->tot_len = 0;
             iph->check = 0;
             tcp_hdr(skb)->check = ~csum_tcpudp_magic(iph->saddr,
                                  iph->daddr, 0,
                                  IPPROTO_TCP,
                                  0);
             cmd_length = E1000_TXD_CMD_IP;
             ipcse = skb_transport_offset(skb) - 1;
         } else if (skb_is_gso_v6(skb)) {
             tcp_v6_gso_csum_prep(skb);
             ipcse = 0;
         }
         ipcss = skb_network_offset(skb);
         ipcso = (void *)&(ip_hdr(skb)->check) - (void *)skb->data;
         tucss = skb_transport_offset(skb);
         tucso = (void *)&(tcp_hdr(skb)->check) - (void *)skb->data;
         tucse = 0;
 
         cmd_length |= (E1000_TXD_CMD_DEXT | E1000_TXD_CMD_TSE |
                    E1000_TXD_CMD_TCP | (skb->len - (hdr_len)));
 
         i = tx_ring->next_to_use;
         context_desc = E1000_CONTEXT_DESC(*tx_ring, i);
         buffer_info = &tx_ring->buffer_info[i];
 
         context_desc->lower_setup.ip_fields.ipcss  = ipcss;
         context_desc->lower_setup.ip_fields.ipcso  = ipcso;
         context_desc->lower_setup.ip_fields.ipcse  = cpu_to_le16(ipcse);
         context_desc->upper_setup.tcp_fields.tucss = tucss;
         context_desc->upper_setup.tcp_fields.tucso = tucso;
         context_desc->upper_setup.tcp_fields.tucse = cpu_to_le16(tucse);
         context_desc->tcp_seg_setup.fields.mss     = cpu_to_le16(mss);
         context_desc->tcp_seg_setup.fields.hdr_len = hdr_len;
         context_desc->cmd_and_length = cpu_to_le32(cmd_length);
 
         buffer_info->time_stamp = jiffies;
         buffer_info->next_to_watch = i;
 
         if (++i == tx_ring->count)
             i = 0;
 
         tx_ring->next_to_use = i;
 
         return true;
     }
     return false;
 }
 
 static bool e1000_tx_csum(struct e1000_adapter *adapter,
               struct e1000_tx_ring *tx_ring, struct sk_buff *skb,
               __be16 protocol)
 {
     struct e1000_context_desc *context_desc;
     struct e1000_tx_buffer *buffer_info;
     unsigned int i;
     u8 css;
     u32 cmd_len = E1000_TXD_CMD_DEXT;
 
     if (skb->ip_summed != CHECKSUM_PARTIAL)
         return false;
 
     switch (protocol) {
     case cpu_to_be16(ETH_P_IP):
         if (ip_hdr(skb)->protocol == IPPROTO_TCP)
             cmd_len |= E1000_TXD_CMD_TCP;
         break;
     case cpu_to_be16(ETH_P_IPV6):
         /* XXX not handling all IPV6 headers */
         if (ipv6_hdr(skb)->nexthdr == IPPROTO_TCP)
             cmd_len |= E1000_TXD_CMD_TCP;
         break;
     default:
         if (unlikely(net_ratelimit()))
             e_warn(drv, "checksum_partial proto=%x!\n",
                    skb->protocol);
         break;
     }
 
     css = skb_checksum_start_offset(skb);
 
     i = tx_ring->next_to_use;
     buffer_info = &tx_ring->buffer_info[i];
     context_desc = E1000_CONTEXT_DESC(*tx_ring, i);
 
     context_desc->lower_setup.ip_config = 0;
     context_desc->upper_setup.tcp_fields.tucss = css;
     context_desc->upper_setup.tcp_fields.tucso =
         css + skb->csum_offset;
     context_desc->upper_setup.tcp_fields.tucse = 0;
     context_desc->tcp_seg_setup.data = 0;
     context_desc->cmd_and_length = cpu_to_le32(cmd_len);
 
     buffer_info->time_stamp = jiffies;
     buffer_info->next_to_watch = i;
 
     if (unlikely(++i == tx_ring->count))
         i = 0;
 
     tx_ring->next_to_use = i;
 
     return true;
 }
 
 #define E1000_MAX_TXD_PWR   12
 #define E1000_MAX_DATA_PER_TXD  (1<<E1000_MAX_TXD_PWR)
 
 static int e1000_tx_map(struct e1000_adapter *adapter,
             struct e1000_tx_ring *tx_ring,
             struct sk_buff *skb, unsigned int first,
             unsigned int max_per_txd, unsigned int nr_frags,
             unsigned int mss)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct pci_dev *pdev = adapter->pdev;
     struct e1000_tx_buffer *buffer_info;
     unsigned int len = skb_headlen(skb);
     unsigned int offset = 0, size, count = 0, i;
     unsigned int f, bytecount, segs;
 
     i = tx_ring->next_to_use;
 
     while (len) {
         buffer_info = &tx_ring->buffer_info[i];
         size = min(len, max_per_txd);
         /* Workaround for Controller erratum --
          * descriptor for non-tso packet in a linear SKB that follows a
          * tso gets written back prematurely before the data is fully
          * DMA'd to the controller
          */
         if (!skb->data_len && tx_ring->last_tx_tso &&
             !skb_is_gso(skb)) {
             tx_ring->last_tx_tso = false;
             size -= 4;
         }
 
         /* Workaround for premature desc write-backs
          * in TSO mode.  Append 4-byte sentinel desc
          */
         if (unlikely(mss && !nr_frags && size == len && size > 8))
             size -= 4;
         /* work-around for errata 10 and it applies
          * to all controllers in PCI-X mode
          * The fix is to make sure that the first descriptor of a
          * packet is smaller than 2048 - 16 - 16 (or 2016) bytes
          */
         if (unlikely((hw->bus_type == e1000_bus_type_pcix) &&
                  (size > 2015) && count == 0))
             size = 2015;
 
         /* Workaround for potential 82544 hang in PCI-X.  Avoid
          * terminating buffers within evenly-aligned dwords.
          */
         if (unlikely(adapter->pcix_82544 &&
            !((unsigned long)(skb->data + offset + size - 1) & 4) &&
            size > 4))
             size -= 4;
 
         buffer_info->length = size;
         /* set time_stamp *before* dma to help avoid a possible race */
         buffer_info->time_stamp = jiffies;
         buffer_info->mapped_as_page = false;
         buffer_info->dma = dma_map_single(&pdev->dev,
                           skb->data + offset,
                           size, DMA_TO_DEVICE);
         if (dma_mapping_error(&pdev->dev, buffer_info->dma))
             goto dma_error;
         buffer_info->next_to_watch = i;
 
         len -= size;
         offset += size;
         count++;
         if (len) {
             i++;
             if (unlikely(i == tx_ring->count))
                 i = 0;
         }
     }
 
     for (f = 0; f < nr_frags; f++) {
         const skb_frag_t *frag = &skb_shinfo(skb)->frags[f];
 
         len = skb_frag_size(frag);
         offset = 0;
 
         while (len) {
             unsigned long bufend;
             i++;
             if (unlikely(i == tx_ring->count))
                 i = 0;
 
             buffer_info = &tx_ring->buffer_info[i];
             size = min(len, max_per_txd);
             /* Workaround for premature desc write-backs
              * in TSO mode.  Append 4-byte sentinel desc
              */
             if (unlikely(mss && f == (nr_frags-1) &&
                 size == len && size > 8))
                 size -= 4;
             /* Workaround for potential 82544 hang in PCI-X.
              * Avoid terminating buffers within evenly-aligned
              * dwords.
              */
             bufend = (unsigned long)
                 page_to_phys(skb_frag_page(frag));
             bufend += offset + size - 1;
             if (unlikely(adapter->pcix_82544 &&
                      !(bufend & 4) &&
                      size > 4))
                 size -= 4;
 
             buffer_info->length = size;
             buffer_info->time_stamp = jiffies;
             buffer_info->mapped_as_page = true;
             buffer_info->dma = skb_frag_dma_map(&pdev->dev, frag,
                         offset, size, DMA_TO_DEVICE);
             if (dma_mapping_error(&pdev->dev, buffer_info->dma))
                 goto dma_error;
             buffer_info->next_to_watch = i;
 
             len -= size;
             offset += size;
             count++;
         }
     }
 
     segs = skb_shinfo(skb)->gso_segs ?: 1;
     /* multiply data chunks by size of headers */
     bytecount = ((segs - 1) * skb_headlen(skb)) + skb->len;
 
     tx_ring->buffer_info[i].skb = skb;
     tx_ring->buffer_info[i].segs = segs;
     tx_ring->buffer_info[i].bytecount = bytecount;
     tx_ring->buffer_info[first].next_to_watch = i;
 
     return count;
 
 dma_error:
     dev_err(&pdev->dev, "TX DMA map failed\n");
     buffer_info->dma = 0;
     if (count)
         count--;
 
     while (count--) {
         if (i == 0)
             i += tx_ring->count;
         i--;
         buffer_info = &tx_ring->buffer_info[i];
         e1000_unmap_and_free_tx_resource(adapter, buffer_info, 0);
     }
 
     return 0;
 }
 
 static void e1000_tx_queue(struct e1000_adapter *adapter,
                struct e1000_tx_ring *tx_ring, int tx_flags,
                int count)
 {
     struct e1000_tx_desc *tx_desc = NULL;
     struct e1000_tx_buffer *buffer_info;
     u32 txd_upper = 0, txd_lower = E1000_TXD_CMD_IFCS;
     unsigned int i;
 
     if (likely(tx_flags & E1000_TX_FLAGS_TSO)) {
         txd_lower |= E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D |
                  E1000_TXD_CMD_TSE;
         txd_upper |= E1000_TXD_POPTS_TXSM << 8;
 
         if (likely(tx_flags & E1000_TX_FLAGS_IPV4))
             txd_upper |= E1000_TXD_POPTS_IXSM << 8;
     }
 
     if (likely(tx_flags & E1000_TX_FLAGS_CSUM)) {
         txd_lower |= E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
         txd_upper |= E1000_TXD_POPTS_TXSM << 8;
     }
 
     if (unlikely(tx_flags & E1000_TX_FLAGS_VLAN)) {
         txd_lower |= E1000_TXD_CMD_VLE;
         txd_upper |= (tx_flags & E1000_TX_FLAGS_VLAN_MASK);
     }
 
     if (unlikely(tx_flags & E1000_TX_FLAGS_NO_FCS))
         txd_lower &= ~(E1000_TXD_CMD_IFCS);
 
     i = tx_ring->next_to_use;
 
     while (count--) {
         buffer_info = &tx_ring->buffer_info[i];
         tx_desc = E1000_TX_DESC(*tx_ring, i);
         tx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
         tx_desc->lower.data =
             cpu_to_le32(txd_lower | buffer_info->length);
         tx_desc->upper.data = cpu_to_le32(txd_upper);
         if (unlikely(++i == tx_ring->count))
             i = 0;
     }
 
     tx_desc->lower.data |= cpu_to_le32(adapter->txd_cmd);
 
     /* txd_cmd re-enables FCS, so we'll re-disable it here as desired. */
     if (unlikely(tx_flags & E1000_TX_FLAGS_NO_FCS))
         tx_desc->lower.data &= ~(cpu_to_le32(E1000_TXD_CMD_IFCS));
 
     /* 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).
      */
     dma_wmb();
 
     tx_ring->next_to_use = i;
 }
 
 /* 82547 workaround to avoid controller hang in half-duplex environment.
  * The workaround is to avoid queuing a large packet that would span
  * the internal Tx FIFO ring boundary by notifying the stack to resend
  * the packet at a later time.  This gives the Tx FIFO an opportunity to
  * flush all packets.  When that occurs, we reset the Tx FIFO pointers
  * to the beginning of the Tx FIFO.
  */
 
 #define E1000_FIFO_HDR          0x10
 #define E1000_82547_PAD_LEN     0x3E0
 
 static int e1000_82547_fifo_workaround(struct e1000_adapter *adapter,
                        struct sk_buff *skb)
 {
     u32 fifo_space = adapter->tx_fifo_size - adapter->tx_fifo_head;
     u32 skb_fifo_len = skb->len + E1000_FIFO_HDR;
 
     skb_fifo_len = ALIGN(skb_fifo_len, E1000_FIFO_HDR);
 
     if (adapter->link_duplex != HALF_DUPLEX)
         goto no_fifo_stall_required;
 
     if (atomic_read(&adapter->tx_fifo_stall))
         return 1;
 
     if (skb_fifo_len >= (E1000_82547_PAD_LEN + fifo_space)) {
         atomic_set(&adapter->tx_fifo_stall, 1);
         return 1;
     }
 
 no_fifo_stall_required:
     adapter->tx_fifo_head += skb_fifo_len;
     if (adapter->tx_fifo_head >= adapter->tx_fifo_size)
         adapter->tx_fifo_head -= adapter->tx_fifo_size;
     return 0;
 }
 
 static int __e1000_maybe_stop_tx(struct net_device *netdev, int size)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_tx_ring *tx_ring = adapter->tx_ring;
 
     netif_stop_queue(netdev);
     /* Herbert's original patch had:
      *  smp_mb__after_netif_stop_queue();
      * but since that doesn't exist yet, just open code it.
      */
     smp_mb();
 
     /* We need to check again in a case another CPU has just
      * made room available.
      */
     if (likely(E1000_DESC_UNUSED(tx_ring) < size))
         return -EBUSY;
 
     /* A reprieve! */
     netif_start_queue(netdev);
     ++adapter->restart_queue;
     return 0;
 }
 
 static int e1000_maybe_stop_tx(struct net_device *netdev,
                    struct e1000_tx_ring *tx_ring, int size)
 {
     if (likely(E1000_DESC_UNUSED(tx_ring) >= size))
         return 0;
     return __e1000_maybe_stop_tx(netdev, size);
 }
 
 #define TXD_USE_COUNT(S, X) (((S) + ((1 << (X)) - 1)) >> (X))
 static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
                     struct net_device *netdev)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     struct e1000_tx_ring *tx_ring;
     unsigned int first, max_per_txd = E1000_MAX_DATA_PER_TXD;
     unsigned int max_txd_pwr = E1000_MAX_TXD_PWR;
     unsigned int tx_flags = 0;
     unsigned int len = skb_headlen(skb);
     unsigned int nr_frags;
     unsigned int mss;
     int count = 0;
     int tso;
     unsigned int f;
     __be16 protocol = vlan_get_protocol(skb);
 
     /* This goes back to the question of how to logically map a Tx queue
      * to a flow.  Right now, performance is impacted slightly negatively
      * if using multiple Tx queues.  If the stack breaks away from a
      * single qdisc implementation, we can look at this again.
      */
     tx_ring = adapter->tx_ring;
 
     /* On PCI/PCI-X HW, if packet size is less than ETH_ZLEN,
      * packets may get corrupted during padding by HW.
      * To WA this issue, pad all small packets manually.
      */
     if (eth_skb_pad(skb))
         return NETDEV_TX_OK;
 
     mss = skb_shinfo(skb)->gso_size;
     /* The controller does a simple calculation to
      * make sure there is enough room in the FIFO before
      * initiating the DMA for each buffer.  The calc is:
      * 4 = ceil(buffer len/mss).  To make sure we don't
      * overrun the FIFO, adjust the max buffer len if mss
      * drops.
      */
     if (mss) {
         u8 hdr_len;
         max_per_txd = min(mss << 2, max_per_txd);
         max_txd_pwr = fls(max_per_txd) - 1;
 
         hdr_len = skb_tcp_all_headers(skb);
         if (skb->data_len && hdr_len == len) {
             switch (hw->mac_type) {
             case e1000_82544: {
                 unsigned int pull_size;
 
                 /* Make sure we have room to chop off 4 bytes,
                  * and that the end alignment will work out to
                  * this hardware's requirements
                  * NOTE: this is a TSO only workaround
                  * if end byte alignment not correct move us
                  * into the next dword
                  */
                 if ((unsigned long)(skb_tail_pointer(skb) - 1)
                     & 4)
                     break;
                 pull_size = min((unsigned int)4, skb->data_len);
                 if (!__pskb_pull_tail(skb, pull_size)) {
                     e_err(drv, "__pskb_pull_tail "
                           "failed.\n");
                     dev_kfree_skb_any(skb);
                     return NETDEV_TX_OK;
                 }
                 len = skb_headlen(skb);
                 break;
             }
             default:
                 /* do nothing */
                 break;
             }
         }
     }
 
     /* reserve a descriptor for the offload context */
     if ((mss) || (skb->ip_summed == CHECKSUM_PARTIAL))
         count++;
     count++;
 
     /* Controller Erratum workaround */
     if (!skb->data_len && tx_ring->last_tx_tso && !skb_is_gso(skb))
         count++;
 
     count += TXD_USE_COUNT(len, max_txd_pwr);
 
     if (adapter->pcix_82544)
         count++;
 
     /* work-around for errata 10 and it applies to all controllers
      * in PCI-X mode, so add one more descriptor to the count
      */
     if (unlikely((hw->bus_type == e1000_bus_type_pcix) &&
             (len > 2015)))
         count++;
 
     nr_frags = skb_shinfo(skb)->nr_frags;
     for (f = 0; f < nr_frags; f++)
         count += TXD_USE_COUNT(skb_frag_size(&skb_shinfo(skb)->frags[f]),
                        max_txd_pwr);
     if (adapter->pcix_82544)
         count += nr_frags;
 
     /* need: count + 2 desc gap to keep tail from touching
      * head, otherwise try next time
      */
     if (unlikely(e1000_maybe_stop_tx(netdev, tx_ring, count + 2)))
         return NETDEV_TX_BUSY;
 
     if (unlikely((hw->mac_type == e1000_82547) &&
              (e1000_82547_fifo_workaround(adapter, skb)))) {
         netif_stop_queue(netdev);
         if (!test_bit(__E1000_DOWN, &adapter->flags))
             schedule_delayed_work(&adapter->fifo_stall_task, 1);
         return NETDEV_TX_BUSY;
     }
 
     if (skb_vlan_tag_present(skb)) {
         tx_flags |= E1000_TX_FLAGS_VLAN;
         tx_flags |= (skb_vlan_tag_get(skb) <<
                  E1000_TX_FLAGS_VLAN_SHIFT);
     }
 
     first = tx_ring->next_to_use;
 
     tso = e1000_tso(adapter, tx_ring, skb, protocol);
     if (tso < 0) {
         dev_kfree_skb_any(skb);
         return NETDEV_TX_OK;
     }
 
     if (likely(tso)) {
         if (likely(hw->mac_type != e1000_82544))
             tx_ring->last_tx_tso = true;
         tx_flags |= E1000_TX_FLAGS_TSO;
     } else if (likely(e1000_tx_csum(adapter, tx_ring, skb, protocol)))
         tx_flags |= E1000_TX_FLAGS_CSUM;
 
     if (protocol == htons(ETH_P_IP))
         tx_flags |= E1000_TX_FLAGS_IPV4;
 
     if (unlikely(skb->no_fcs))
         tx_flags |= E1000_TX_FLAGS_NO_FCS;
 
     count = e1000_tx_map(adapter, tx_ring, skb, first, max_per_txd,
                  nr_frags, mss);
 
     if (count) {
         /* The descriptors needed is higher than other Intel drivers
          * due to a number of workarounds.  The breakdown is below:
          * Data descriptors: MAX_SKB_FRAGS + 1
          * Context Descriptor: 1
          * Keep head from touching tail: 2
          * Workarounds: 3
          */
         int desc_needed = MAX_SKB_FRAGS + 7;
 
         netdev_sent_queue(netdev, skb->len);
         skb_tx_timestamp(skb);
 
         e1000_tx_queue(adapter, tx_ring, tx_flags, count);
 
         /* 82544 potentially requires twice as many data descriptors
          * in order to guarantee buffers don't end on evenly-aligned
          * dwords
          */
         if (adapter->pcix_82544)
             desc_needed += MAX_SKB_FRAGS + 1;
 
         /* Make sure there is space in the ring for the next send. */
         e1000_maybe_stop_tx(netdev, tx_ring, desc_needed);
 
         if (!netdev_xmit_more() ||
             netif_xmit_stopped(netdev_get_tx_queue(netdev, 0))) {
             writel(tx_ring->next_to_use, hw->hw_addr + tx_ring->tdt);
         }
     } else {
         dev_kfree_skb_any(skb);
         tx_ring->buffer_info[first].time_stamp = 0;
         tx_ring->next_to_use = first;
     }
 
     return NETDEV_TX_OK;
 }
 
 #define NUM_REGS 38 /* 1 based count */
 static void e1000_regdump(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     u32 regs[NUM_REGS];
     u32 *regs_buff = regs;
     int i = 0;
 
     static const char * const reg_name[] = {
         "CTRL",  "STATUS",
         "RCTL", "RDLEN", "RDH", "RDT", "RDTR",
         "TCTL", "TDBAL", "TDBAH", "TDLEN", "TDH", "TDT",
         "TIDV", "TXDCTL", "TADV", "TARC0",
         "TDBAL1", "TDBAH1", "TDLEN1", "TDH1", "TDT1",
         "TXDCTL1", "TARC1",
         "CTRL_EXT", "ERT", "RDBAL", "RDBAH",
         "TDFH", "TDFT", "TDFHS", "TDFTS", "TDFPC",
         "RDFH", "RDFT", "RDFHS", "RDFTS", "RDFPC"
     };
 
     regs_buff[0]  = er32(CTRL);
     regs_buff[1]  = er32(STATUS);
 
     regs_buff[2]  = er32(RCTL);
     regs_buff[3]  = er32(RDLEN);
     regs_buff[4]  = er32(RDH);
     regs_buff[5]  = er32(RDT);
     regs_buff[6]  = er32(RDTR);
 
     regs_buff[7]  = er32(TCTL);
     regs_buff[8]  = er32(TDBAL);
     regs_buff[9]  = er32(TDBAH);
     regs_buff[10] = er32(TDLEN);
     regs_buff[11] = er32(TDH);
     regs_buff[12] = er32(TDT);
     regs_buff[13] = er32(TIDV);
     regs_buff[14] = er32(TXDCTL);
     regs_buff[15] = er32(TADV);
     regs_buff[16] = er32(TARC0);
 
     regs_buff[17] = er32(TDBAL1);
     regs_buff[18] = er32(TDBAH1);
     regs_buff[19] = er32(TDLEN1);
     regs_buff[20] = er32(TDH1);
     regs_buff[21] = er32(TDT1);
     regs_buff[22] = er32(TXDCTL1);
     regs_buff[23] = er32(TARC1);
     regs_buff[24] = er32(CTRL_EXT);
     regs_buff[25] = er32(ERT);
     regs_buff[26] = er32(RDBAL0);
     regs_buff[27] = er32(RDBAH0);
     regs_buff[28] = er32(TDFH);
     regs_buff[29] = er32(TDFT);
     regs_buff[30] = er32(TDFHS);
     regs_buff[31] = er32(TDFTS);
     regs_buff[32] = er32(TDFPC);
     regs_buff[33] = er32(RDFH);
     regs_buff[34] = er32(RDFT);
     regs_buff[35] = er32(RDFHS);
     regs_buff[36] = er32(RDFTS);
     regs_buff[37] = er32(RDFPC);
 
     pr_info("Register dump\n");
     for (i = 0; i < NUM_REGS; i++)
         pr_info("%-15s  %08x\n", reg_name[i], regs_buff[i]);
 }
 
 /*
  * e1000_dump: Print registers, tx ring and rx ring
  */
 static void e1000_dump(struct e1000_adapter *adapter)
 {
     /* this code doesn't handle multiple rings */
     struct e1000_tx_ring *tx_ring = adapter->tx_ring;
     struct e1000_rx_ring *rx_ring = adapter->rx_ring;
     int i;
 
     if (!netif_msg_hw(adapter))
         return;
 
     /* Print Registers */
     e1000_regdump(adapter);
 
     /* transmit dump */
     pr_info("TX Desc ring0 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("Tc[desc]     [Ce CoCsIpceCoS] [MssHlRSCm0Plen] [bi->dma       ] leng  ntw timestmp         bi->skb\n");
     pr_info("Td[desc]     [address 63:0  ] [VlaPoRSCm1Dlen] [bi->dma       ] leng  ntw timestmp         bi->skb\n");
 
     if (!netif_msg_tx_done(adapter))
         goto rx_ring_summary;
 
     for (i = 0; tx_ring->desc && (i < tx_ring->count); i++) {
         struct e1000_tx_desc *tx_desc = E1000_TX_DESC(*tx_ring, i);
         struct e1000_tx_buffer *buffer_info = &tx_ring->buffer_info[i];
         struct my_u { __le64 a; __le64 b; };
         struct my_u *u = (struct my_u *)tx_desc;
         const char *type;
 
         if (i == tx_ring->next_to_use && i == tx_ring->next_to_clean)
             type = "NTC/U";
         else if (i == tx_ring->next_to_use)
             type = "NTU";
         else if (i == tx_ring->next_to_clean)
             type = "NTC";
         else
             type = "";
 
         pr_info("T%c[0x%03X]    %016llX %016llX %016llX %04X  %3X %016llX %p %s\n",
             ((le64_to_cpu(u->b) & (1<<20)) ? 'd' : 'c'), i,
             le64_to_cpu(u->a), le64_to_cpu(u->b),
             (u64)buffer_info->dma, buffer_info->length,
             buffer_info->next_to_watch,
             (u64)buffer_info->time_stamp, buffer_info->skb, type);
     }
 
 rx_ring_summary:
     /* receive dump */
     pr_info("\nRX Desc ring dump\n");
 
     /* Legacy Receive Descriptor Format
      *
      * +-----------------------------------------------------+
      * |                Buffer Address [63:0]                |
      * +-----------------------------------------------------+
      * | VLAN Tag | Errors | Status 0 | Packet csum | Length |
      * +-----------------------------------------------------+
      * 63       48 47    40 39      32 31         16 15      0
      */
     pr_info("R[desc]      [address 63:0  ] [vl er S cks ln] [bi->dma       ] [bi->skb]\n");
 
     if (!netif_msg_rx_status(adapter))
         goto exit;
 
     for (i = 0; rx_ring->desc && (i < rx_ring->count); i++) {
         struct e1000_rx_desc *rx_desc = E1000_RX_DESC(*rx_ring, i);
         struct e1000_rx_buffer *buffer_info = &rx_ring->buffer_info[i];
         struct my_u { __le64 a; __le64 b; };
         struct my_u *u = (struct my_u *)rx_desc;
         const char *type;
 
         if (i == rx_ring->next_to_use)
             type = "NTU";
         else if (i == rx_ring->next_to_clean)
             type = "NTC";
         else
             type = "";
 
         pr_info("R[0x%03X]     %016llX %016llX %016llX %p %s\n",
             i, le64_to_cpu(u->a), le64_to_cpu(u->b),
             (u64)buffer_info->dma, buffer_info->rxbuf.data, type);
     } /* for */
 
     /* dump the descriptor caches */
     /* rx */
     pr_info("Rx descriptor cache in 64bit format\n");
     for (i = 0x6000; i <= 0x63FF ; i += 0x10) {
         pr_info("R%04X: %08X|%08X %08X|%08X\n",
             i,
             readl(adapter->hw.hw_addr + i+4),
             readl(adapter->hw.hw_addr + i),
             readl(adapter->hw.hw_addr + i+12),
             readl(adapter->hw.hw_addr + i+8));
     }
     /* tx */
     pr_info("Tx descriptor cache in 64bit format\n");
     for (i = 0x7000; i <= 0x73FF ; i += 0x10) {
         pr_info("T%04X: %08X|%08X %08X|%08X\n",
             i,
             readl(adapter->hw.hw_addr + i+4),
             readl(adapter->hw.hw_addr + i),
             readl(adapter->hw.hw_addr + i+12),
             readl(adapter->hw.hw_addr + i+8));
     }
 exit:
     return;
 }
 
 /**
  * e1000_tx_timeout - Respond to a Tx Hang
  * @netdev: network interface device structure
  * @txqueue: number of the Tx queue that hung (unused)
  **/
 static void e1000_tx_timeout(struct net_device *netdev, unsigned int __always_unused txqueue)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
 
     /* Do the reset outside of interrupt context */
     adapter->tx_timeout_count++;
     schedule_work(&adapter->reset_task);
 }
 
 static void e1000_reset_task(struct work_struct *work)
 {
     struct e1000_adapter *adapter =
         container_of(work, struct e1000_adapter, reset_task);
 
     e_err(drv, "Reset adapter\n");
     e1000_reinit_locked(adapter);
 }
 
 /**
  * e1000_change_mtu - Change the Maximum Transfer Unit
  * @netdev: network interface device structure
  * @new_mtu: new value for maximum frame size
  *
  * Returns 0 on success, negative on failure
  **/
 static int e1000_change_mtu(struct net_device *netdev, int new_mtu)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN;
 
     /* Adapter-specific max frame size limits. */
     switch (hw->mac_type) {
     case e1000_undefined ... e1000_82542_rev2_1:
         if (max_frame > (ETH_FRAME_LEN + ETH_FCS_LEN)) {
             e_err(probe, "Jumbo Frames not supported.\n");
             return -EINVAL;
         }
         break;
     default:
         /* Capable of supporting up to MAX_JUMBO_FRAME_SIZE limit. */
         break;
     }
 
     while (test_and_set_bit(__E1000_RESETTING, &adapter->flags))
         msleep(1);
     /* e1000_down has a dependency on max_frame_size */
     hw->max_frame_size = max_frame;
     if (netif_running(netdev)) {
         /* prevent buffers from being reallocated */
         adapter->alloc_rx_buf = e1000_alloc_dummy_rx_buffers;
         e1000_down(adapter);
     }
 
     /* NOTE: netdev_alloc_skb reserves 16 bytes, and typically NET_IP_ALIGN
      * means we reserve 2 more, this pushes us to allocate from the next
      * larger slab size.
      * i.e. RXBUFFER_2048 --> size-4096 slab
      * however with the new *_jumbo_rx* routines, jumbo receives will use
      * fragmented skbs
      */
 
     if (max_frame <= E1000_RXBUFFER_2048)
         adapter->rx_buffer_len = E1000_RXBUFFER_2048;
     else
 #if (PAGE_SIZE >= E1000_RXBUFFER_16384)
         adapter->rx_buffer_len = E1000_RXBUFFER_16384;
 #elif (PAGE_SIZE >= E1000_RXBUFFER_4096)
         adapter->rx_buffer_len = PAGE_SIZE;
 #endif
 
     /* adjust allocation if LPE protects us, and we aren't using SBP */
     if (!hw->tbi_compatibility_on &&
         ((max_frame == (ETH_FRAME_LEN + ETH_FCS_LEN)) ||
          (max_frame == MAXIMUM_ETHERNET_VLAN_SIZE)))
         adapter->rx_buffer_len = MAXIMUM_ETHERNET_VLAN_SIZE;
 
     netdev_dbg(netdev, "changing MTU from %d to %d\n",
            netdev->mtu, new_mtu);
     netdev->mtu = new_mtu;
 
     if (netif_running(netdev))
         e1000_up(adapter);
     else
         e1000_reset(adapter);
 
     clear_bit(__E1000_RESETTING, &adapter->flags);
 
     return 0;
 }
 
 /**
  * e1000_update_stats - Update the board statistics counters
  * @adapter: board private structure
  **/
 void e1000_update_stats(struct e1000_adapter *adapter)
 {
     struct net_device *netdev = adapter->netdev;
     struct e1000_hw *hw = &adapter->hw;
     struct pci_dev *pdev = adapter->pdev;
     unsigned long flags;
     u16 phy_tmp;
 
 #define PHY_IDLE_ERROR_COUNT_MASK 0x00FF
 
     /* Prevent stats update while adapter is being reset, or if the pci
      * connection is down.
      */
     if (adapter->link_speed == 0)
         return;
     if (pci_channel_offline(pdev))
         return;
 
     spin_lock_irqsave(&adapter->stats_lock, flags);
 
     /* these counters are modified from e1000_tbi_adjust_stats,
      * called from the interrupt context, so they must only
      * be written while holding adapter->stats_lock
      */
 
     adapter->stats.crcerrs += er32(CRCERRS);
     adapter->stats.gprc += er32(GPRC);
     adapter->stats.gorcl += er32(GORCL);
     adapter->stats.gorch += er32(GORCH);
     adapter->stats.bprc += er32(BPRC);
     adapter->stats.mprc += er32(MPRC);
     adapter->stats.roc += er32(ROC);
 
     adapter->stats.prc64 += er32(PRC64);
     adapter->stats.prc127 += er32(PRC127);
     adapter->stats.prc255 += er32(PRC255);
     adapter->stats.prc511 += er32(PRC511);
     adapter->stats.prc1023 += er32(PRC1023);
     adapter->stats.prc1522 += er32(PRC1522);
 
     adapter->stats.symerrs += er32(SYMERRS);
     adapter->stats.mpc += er32(MPC);
     adapter->stats.scc += er32(SCC);
     adapter->stats.ecol += er32(ECOL);
     adapter->stats.mcc += er32(MCC);
     adapter->stats.latecol += er32(LATECOL);
     adapter->stats.dc += er32(DC);
     adapter->stats.sec += er32(SEC);
     adapter->stats.rlec += er32(RLEC);
     adapter->stats.xonrxc += er32(XONRXC);
     adapter->stats.xontxc += er32(XONTXC);
     adapter->stats.xoffrxc += er32(XOFFRXC);
     adapter->stats.xofftxc += er32(XOFFTXC);
     adapter->stats.fcruc += er32(FCRUC);
     adapter->stats.gptc += er32(GPTC);
     adapter->stats.gotcl += er32(GOTCL);
     adapter->stats.gotch += er32(GOTCH);
     adapter->stats.rnbc += er32(RNBC);
     adapter->stats.ruc += er32(RUC);
     adapter->stats.rfc += er32(RFC);
     adapter->stats.rjc += er32(RJC);
     adapter->stats.torl += er32(TORL);
     adapter->stats.torh += er32(TORH);
     adapter->stats.totl += er32(TOTL);
     adapter->stats.toth += er32(TOTH);
     adapter->stats.tpr += er32(TPR);
 
     adapter->stats.ptc64 += er32(PTC64);
     adapter->stats.ptc127 += er32(PTC127);
     adapter->stats.ptc255 += er32(PTC255);
     adapter->stats.ptc511 += er32(PTC511);
     adapter->stats.ptc1023 += er32(PTC1023);
     adapter->stats.ptc1522 += er32(PTC1522);
 
     adapter->stats.mptc += er32(MPTC);
     adapter->stats.bptc += er32(BPTC);
 
     /* used for adaptive IFS */
 
     hw->tx_packet_delta = er32(TPT);
     adapter->stats.tpt += hw->tx_packet_delta;
     hw->collision_delta = er32(COLC);
     adapter->stats.colc += hw->collision_delta;
 
     if (hw->mac_type >= e1000_82543) {
         adapter->stats.algnerrc += er32(ALGNERRC);
         adapter->stats.rxerrc += er32(RXERRC);
         adapter->stats.tncrs += er32(TNCRS);
         adapter->stats.cexterr += er32(CEXTERR);
         adapter->stats.tsctc += er32(TSCTC);
         adapter->stats.tsctfc += er32(TSCTFC);
     }
 
     /* Fill out the OS statistics structure */
     netdev->stats.multicast = adapter->stats.mprc;
     netdev->stats.collisions = adapter->stats.colc;
 
     /* Rx Errors */
 
     /* RLEC on some newer hardware can be incorrect so build
      * our own version based on RUC and ROC
      */
     netdev->stats.rx_errors = adapter->stats.rxerrc +
         adapter->stats.crcerrs + adapter->stats.algnerrc +
         adapter->stats.ruc + adapter->stats.roc +
         adapter->stats.cexterr;
     adapter->stats.rlerrc = adapter->stats.ruc + adapter->stats.roc;
     netdev->stats.rx_length_errors = adapter->stats.rlerrc;
     netdev->stats.rx_crc_errors = adapter->stats.crcerrs;
     netdev->stats.rx_frame_errors = adapter->stats.algnerrc;
     netdev->stats.rx_missed_errors = adapter->stats.mpc;
 
     /* Tx Errors */
     adapter->stats.txerrc = adapter->stats.ecol + adapter->stats.latecol;
     netdev->stats.tx_errors = adapter->stats.txerrc;
     netdev->stats.tx_aborted_errors = adapter->stats.ecol;
     netdev->stats.tx_window_errors = adapter->stats.latecol;
     netdev->stats.tx_carrier_errors = adapter->stats.tncrs;
     if (hw->bad_tx_carr_stats_fd &&
         adapter->link_duplex == FULL_DUPLEX) {
         netdev->stats.tx_carrier_errors = 0;
         adapter->stats.tncrs = 0;
     }
 
     /* Tx Dropped needs to be maintained elsewhere */
 
     /* Phy Stats */
     if (hw->media_type == e1000_media_type_copper) {
         if ((adapter->link_speed == SPEED_1000) &&
            (!e1000_read_phy_reg(hw, PHY_1000T_STATUS, &phy_tmp))) {
             phy_tmp &= PHY_IDLE_ERROR_COUNT_MASK;
             adapter->phy_stats.idle_errors += phy_tmp;
         }
 
         if ((hw->mac_type <= e1000_82546) &&
            (hw->phy_type == e1000_phy_m88) &&
            !e1000_read_phy_reg(hw, M88E1000_RX_ERR_CNTR, &phy_tmp))
             adapter->phy_stats.receive_errors += phy_tmp;
     }
 
     /* Management Stats */
     if (hw->has_smbus) {
         adapter->stats.mgptc += er32(MGTPTC);
         adapter->stats.mgprc += er32(MGTPRC);
         adapter->stats.mgpdc += er32(MGTPDC);
     }
 
     spin_unlock_irqrestore(&adapter->stats_lock, flags);
 }
 
 /**
  * e1000_intr - Interrupt Handler
  * @irq: interrupt number
  * @data: pointer to a network interface device structure
  **/
 static irqreturn_t e1000_intr(int irq, void *data)
 {
     struct net_device *netdev = data;
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     u32 icr = er32(ICR);
 
     if (unlikely((!icr)))
         return IRQ_NONE;  /* Not our interrupt */
 
     /* we might have caused the interrupt, but the above
      * read cleared it, and just in case the driver is
      * down there is nothing to do so return handled
      */
     if (unlikely(test_bit(__E1000_DOWN, &adapter->flags)))
         return IRQ_HANDLED;
 
     if (unlikely(icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC))) {
         hw->get_link_status = 1;
         /* guard against interrupt when we're going down */
         if (!test_bit(__E1000_DOWN, &adapter->flags))
             schedule_delayed_work(&adapter->watchdog_task, 1);
     }
 
     /* disable interrupts, without the synchronize_irq bit */
     ew32(IMC, ~0);
     E1000_WRITE_FLUSH();
 
     if (likely(napi_schedule_prep(&adapter->napi))) {
         adapter->total_tx_bytes = 0;
         adapter->total_tx_packets = 0;
         adapter->total_rx_bytes = 0;
         adapter->total_rx_packets = 0;
         __napi_schedule(&adapter->napi);
     } else {
         /* this really should not happen! if it does it is basically a
          * bug, but not a hard error, so enable ints and continue
          */
         if (!test_bit(__E1000_DOWN, &adapter->flags))
             e1000_irq_enable(adapter);
     }
 
     return IRQ_HANDLED;
 }
 
 /**
  * e1000_clean - NAPI Rx polling callback
  * @napi: napi struct containing references to driver info
  * @budget: budget given to driver for receive packets
  **/
 static int e1000_clean(struct napi_struct *napi, int budget)
 {
     struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter,
                              napi);
     int tx_clean_complete = 0, work_done = 0;
 
     tx_clean_complete = e1000_clean_tx_irq(adapter, &adapter->tx_ring[0]);
 
     adapter->clean_rx(adapter, &adapter->rx_ring[0], &work_done, budget);
 
     if (!tx_clean_complete || work_done == budget)
         return budget;
 
     /* Exit the polling mode, but don't re-enable interrupts if stack might
      * poll us due to busy-polling
      */
     if (likely(napi_complete_done(napi, work_done))) {
         if (likely(adapter->itr_setting & 3))
             e1000_set_itr(adapter);
         if (!test_bit(__E1000_DOWN, &adapter->flags))
             e1000_irq_enable(adapter);
     }
 
     return work_done;
 }
 
 /**
  * e1000_clean_tx_irq - Reclaim resources after transmit completes
  * @adapter: board private structure
  * @tx_ring: ring to clean
  **/
 static bool e1000_clean_tx_irq(struct e1000_adapter *adapter,
                    struct e1000_tx_ring *tx_ring)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct net_device *netdev = adapter->netdev;
     struct e1000_tx_desc *tx_desc, *eop_desc;
     struct e1000_tx_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_unmap_and_free_tx_resource(adapter, buffer_info,
                              64);
             tx_desc->upper.data = 0;
 
             if (unlikely(++i == tx_ring->count))
                 i = 0;
         }
 
         eop = tx_ring->buffer_info[i].next_to_watch;
         eop_desc = E1000_TX_DESC(*tx_ring, eop);
     }
 
     /* Synchronize with E1000_DESC_UNUSED called from e1000_xmit_frame,
      * which will reuse the cleaned buffers.
      */
     smp_store_release(&tx_ring->next_to_clean, i);
 
     netdev_completed_queue(netdev, pkts_compl, bytes_compl);
 
 #define TX_WAKE_THRESHOLD 32
     if (unlikely(count && netif_carrier_ok(netdev) &&
              E1000_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD)) {
         /* Make sure that anybody stopping the queue after this
          * sees the new next_to_clean.
          */
         smp_mb();
 
         if (netif_queue_stopped(netdev) &&
             !(test_bit(__E1000_DOWN, &adapter->flags))) {
             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[eop].time_stamp &&
             time_after(jiffies, tx_ring->buffer_info[eop].time_stamp +
                    (adapter->tx_timeout_factor * HZ)) &&
             !(er32(STATUS) & E1000_STATUS_TXOFF)) {
 
             /* detected Tx unit hang */
             e_err(drv, "Detected Tx Unit Hang\n"
                   "  Tx Queue             <%lu>\n"
                   "  TDH                  <%x>\n"
                   "  TDT                  <%x>\n"
                   "  next_to_use          <%x>\n"
                   "  next_to_clean        <%x>\n"
                   "buffer_info[next_to_clean]\n"
                   "  time_stamp           <%lx>\n"
                   "  next_to_watch        <%x>\n"
                   "  jiffies              <%lx>\n"
                   "  next_to_watch.status <%x>\n",
                 (unsigned long)(tx_ring - adapter->tx_ring),
                 readl(hw->hw_addr + tx_ring->tdh),
                 readl(hw->hw_addr + tx_ring->tdt),
                 tx_ring->next_to_use,
                 tx_ring->next_to_clean,
                 tx_ring->buffer_info[eop].time_stamp,
                 eop,
                 jiffies,
                 eop_desc->upper.fields.status);
             e1000_dump(adapter);
             netif_stop_queue(netdev);
         }
     }
     adapter->total_tx_bytes += total_tx_bytes;
     adapter->total_tx_packets += total_tx_packets;
     netdev->stats.tx_bytes += total_tx_bytes;
     netdev->stats.tx_packets += total_tx_packets;
     return count < tx_ring->count;
 }
 
 /**
  * e1000_rx_checksum - Receive Checksum Offload for 82543
  * @adapter:     board private structure
  * @status_err:  receive descriptor status and error fields
  * @csum:        receive descriptor csum field
  * @skb:         socket buffer with received data
  **/
 static void e1000_rx_checksum(struct e1000_adapter *adapter, u32 status_err,
                   u32 csum, struct sk_buff *skb)
 {
     struct e1000_hw *hw = &adapter->hw;
     u16 status = (u16)status_err;
     u8 errors = (u8)(status_err >> 24);
 
     skb_checksum_none_assert(skb);
 
     /* 82543 or newer only */
     if (unlikely(hw->mac_type < e1000_82543))
         return;
     /* Ignore Checksum bit is set */
     if (unlikely(status & E1000_RXD_STAT_IXSM))
         return;
     /* TCP/UDP checksum error bit is set */
     if (unlikely(errors & E1000_RXD_ERR_TCPE)) {
         /* let the stack verify checksum errors */
         adapter->hw_csum_err++;
         return;
     }
     /* TCP/UDP Checksum has not been calculated */
     if (!(status & E1000_RXD_STAT_TCPCS))
         return;
 
     /* It must be a TCP or UDP packet with a valid checksum */
     if (likely(status & E1000_RXD_STAT_TCPCS)) {
         /* TCP checksum is good */
         skb->ip_summed = CHECKSUM_UNNECESSARY;
     }
     adapter->hw_csum_good++;
 }
 
 /**
  * e1000_consume_page - helper function for jumbo Rx path
  * @bi: software descriptor shadow data
  * @skb: skb being modified
  * @length: length of data being added
  **/
 static void e1000_consume_page(struct e1000_rx_buffer *bi, struct sk_buff *skb,
                    u16 length)
 {
     bi->rxbuf.page = NULL;
     skb->len += length;
     skb->data_len += length;
     skb->truesize += PAGE_SIZE;
 }
 
 /**
  * e1000_receive_skb - helper function to handle rx indications
  * @adapter: board private structure
  * @status: descriptor status field as written by hardware
  * @vlan: descriptor vlan field as written by hardware (no le/be conversion)
  * @skb: pointer to sk_buff to be indicated to stack
  */
 static void e1000_receive_skb(struct e1000_adapter *adapter, u8 status,
                   __le16 vlan, struct sk_buff *skb)
 {
     skb->protocol = eth_type_trans(skb, adapter->netdev);
 
     if (status & E1000_RXD_STAT_VP) {
         u16 vid = le16_to_cpu(vlan) & E1000_RXD_SPC_VLAN_MASK;
 
         __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vid);
     }
     napi_gro_receive(&adapter->napi, skb);
 }
 
 /**
  * e1000_tbi_adjust_stats
  * @hw: Struct containing variables accessed by shared code
  * @stats: point to stats struct
  * @frame_len: The length of the frame in question
  * @mac_addr: The Ethernet destination address of the frame in question
  *
  * Adjusts the statistic counters when a frame is accepted by TBI_ACCEPT
  */
 static void e1000_tbi_adjust_stats(struct e1000_hw *hw,
                    struct e1000_hw_stats *stats,
                    u32 frame_len, const u8 *mac_addr)
 {
     u64 carry_bit;
 
     /* First adjust the frame length. */
     frame_len--;
     /* We need to adjust the statistics counters, since the hardware
      * counters overcount this packet as a CRC error and undercount
      * the packet as a good packet
      */
     /* This packet should not be counted as a CRC error. */
     stats->crcerrs--;
     /* This packet does count as a Good Packet Received. */
     stats->gprc++;
 
     /* Adjust the Good Octets received counters */
     carry_bit = 0x80000000 & stats->gorcl;
     stats->gorcl += frame_len;
     /* If the high bit of Gorcl (the low 32 bits of the Good Octets
      * Received Count) was one before the addition,
      * AND it is zero after, then we lost the carry out,
      * need to add one to Gorch (Good Octets Received Count High).
      * This could be simplified if all environments supported
      * 64-bit integers.
      */
     if (carry_bit && ((stats->gorcl & 0x80000000) == 0))
         stats->gorch++;
     /* Is this a broadcast or multicast?  Check broadcast first,
      * since the test for a multicast frame will test positive on
      * a broadcast frame.
      */
     if (is_broadcast_ether_addr(mac_addr))
         stats->bprc++;
     else if (is_multicast_ether_addr(mac_addr))
         stats->mprc++;
 
     if (frame_len == hw->max_frame_size) {
         /* In this case, the hardware has overcounted the number of
          * oversize frames.
          */
         if (stats->roc > 0)
             stats->roc--;
     }
 
     /* Adjust the bin counters when the extra byte put the frame in the
      * wrong bin. Remember that the frame_len was adjusted above.
      */
     if (frame_len == 64) {
         stats->prc64++;
         stats->prc127--;
     } else if (frame_len == 127) {
         stats->prc127++;
         stats->prc255--;
     } else if (frame_len == 255) {
         stats->prc255++;
         stats->prc511--;
     } else if (frame_len == 511) {
         stats->prc511++;
         stats->prc1023--;
     } else if (frame_len == 1023) {
         stats->prc1023++;
         stats->prc1522--;
     } else if (frame_len == 1522) {
         stats->prc1522++;
     }
 }
 
 static bool e1000_tbi_should_accept(struct e1000_adapter *adapter,
                     u8 status, u8 errors,
                     u32 length, const u8 *data)
 {
     struct e1000_hw *hw = &adapter->hw;
     u8 last_byte = *(data + length - 1);
 
     if (TBI_ACCEPT(hw, status, errors, length, last_byte)) {
         unsigned long irq_flags;
 
         spin_lock_irqsave(&adapter->stats_lock, irq_flags);
         e1000_tbi_adjust_stats(hw, &adapter->stats, length, data);
         spin_unlock_irqrestore(&adapter->stats_lock, irq_flags);
 
         return true;
     }
 
     return false;
 }
 
 static struct sk_buff *e1000_alloc_rx_skb(struct e1000_adapter *adapter,
                       unsigned int bufsz)
 {
     struct sk_buff *skb = napi_alloc_skb(&adapter->napi, bufsz);
 
     if (unlikely(!skb))
         adapter->alloc_rx_buff_failed++;
     return skb;
 }
 
 /**
  * e1000_clean_jumbo_rx_irq - Send received data up the network stack; legacy
  * @adapter: board private structure
  * @rx_ring: ring to clean
  * @work_done: amount of napi work completed this call
  * @work_to_do: max amount of work allowed for this call to do
  *
  * the return value indicates whether actual cleaning was done, there
  * is no guarantee that everything was cleaned
  */
 static bool e1000_clean_jumbo_rx_irq(struct e1000_adapter *adapter,
                      struct e1000_rx_ring *rx_ring,
                      int *work_done, int work_to_do)
 {
     struct net_device *netdev = adapter->netdev;
     struct pci_dev *pdev = adapter->pdev;
     struct e1000_rx_desc *rx_desc, *next_rxd;
     struct e1000_rx_buffer *buffer_info, *next_buffer;
     u32 length;
     unsigned int i;
     int cleaned_count = 0;
     bool cleaned = false;
     unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 
     i = rx_ring->next_to_clean;
     rx_desc = E1000_RX_DESC(*rx_ring, i);
     buffer_info = &rx_ring->buffer_info[i];
 
     while (rx_desc->status & E1000_RXD_STAT_DD) {
         struct sk_buff *skb;
         u8 status;
 
         if (*work_done >= work_to_do)
             break;
         (*work_done)++;
         dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
 
         status = rx_desc->status;
 
         if (++i == rx_ring->count)
             i = 0;
 
         next_rxd = E1000_RX_DESC(*rx_ring, i);
         prefetch(next_rxd);
 
         next_buffer = &rx_ring->buffer_info[i];
 
         cleaned = true;
         cleaned_count++;
         dma_unmap_page(&pdev->dev, buffer_info->dma,
                    adapter->rx_buffer_len, DMA_FROM_DEVICE);
         buffer_info->dma = 0;
 
         length = le16_to_cpu(rx_desc->length);
 
         /* errors is only valid for DD + EOP descriptors */
         if (unlikely((status & E1000_RXD_STAT_EOP) &&
             (rx_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK))) {
             u8 *mapped = page_address(buffer_info->rxbuf.page);
 
             if (e1000_tbi_should_accept(adapter, status,
                             rx_desc->errors,
                             length, mapped)) {
                 length--;
             } else if (netdev->features & NETIF_F_RXALL) {
                 goto process_skb;
             } else {
                 /* an error means any chain goes out the window
                  * too
                  */
                 dev_kfree_skb(rx_ring->rx_skb_top);
                 rx_ring->rx_skb_top = NULL;
                 goto next_desc;
             }
         }
 
 #define rxtop rx_ring->rx_skb_top
 process_skb:
         if (!(status & E1000_RXD_STAT_EOP)) {
             /* this descriptor is only the beginning (or middle) */
             if (!rxtop) {
                 /* this is the beginning of a chain */
                 rxtop = napi_get_frags(&adapter->napi);
                 if (!rxtop)
                     break;
 
                 skb_fill_page_desc(rxtop, 0,
                            buffer_info->rxbuf.page,
                            0, length);
             } else {
                 /* this is the middle of a chain */
                 skb_fill_page_desc(rxtop,
                     skb_shinfo(rxtop)->nr_frags,
                     buffer_info->rxbuf.page, 0, length);
             }
             e1000_consume_page(buffer_info, rxtop, length);
             goto next_desc;
         } else {
             if (rxtop) {
                 /* end of the chain */
                 skb_fill_page_desc(rxtop,
                     skb_shinfo(rxtop)->nr_frags,
                     buffer_info->rxbuf.page, 0, length);
                 skb = rxtop;
                 rxtop = NULL;
                 e1000_consume_page(buffer_info, skb, length);
             } else {
                 struct page *p;
                 /* no chain, got EOP, this buf is the packet
                  * copybreak to save the put_page/alloc_page
                  */
                 p = buffer_info->rxbuf.page;
                 if (length <= copybreak) {
                     u8 *vaddr;
 
                     if (likely(!(netdev->features & NETIF_F_RXFCS)))
                         length -= 4;
                     skb = e1000_alloc_rx_skb(adapter,
                                  length);
                     if (!skb)
                         break;
 
                     vaddr = kmap_atomic(p);
                     memcpy(skb_tail_pointer(skb), vaddr,
                            length);
                     kunmap_atomic(vaddr);
                     /* re-use the page, so don't erase
                      * buffer_info->rxbuf.page
                      */
                     skb_put(skb, length);
                     e1000_rx_checksum(adapter,
                               status | rx_desc->errors << 24,
                               le16_to_cpu(rx_desc->csum), skb);
 
                     total_rx_bytes += skb->len;
                     total_rx_packets++;
 
                     e1000_receive_skb(adapter, status,
                               rx_desc->special, skb);
                     goto next_desc;
                 } else {
                     skb = napi_get_frags(&adapter->napi);
                     if (!skb) {
                         adapter->alloc_rx_buff_failed++;
                         break;
                     }
                     skb_fill_page_desc(skb, 0, p, 0,
                                length);
                     e1000_consume_page(buffer_info, skb,
                                length);
                 }
             }
         }
 
         /* Receive Checksum Offload XXX recompute due to CRC strip? */
         e1000_rx_checksum(adapter,
                   (u32)(status) |
                   ((u32)(rx_desc->errors) << 24),
                   le16_to_cpu(rx_desc->csum), skb);
 
         total_rx_bytes += (skb->len - 4); /* don't count FCS */
         if (likely(!(netdev->features & NETIF_F_RXFCS)))
             pskb_trim(skb, skb->len - 4);
         total_rx_packets++;
 
         if (status & E1000_RXD_STAT_VP) {
             __le16 vlan = rx_desc->special;
             u16 vid = le16_to_cpu(vlan) & E1000_RXD_SPC_VLAN_MASK;
 
             __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vid);
         }
 
         napi_gro_frags(&adapter->napi);
 
 next_desc:
         rx_desc->status = 0;
 
         /* return some buffers to hardware, one at a time is too slow */
         if (unlikely(cleaned_count >= E1000_RX_BUFFER_WRITE)) {
             adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);
             cleaned_count = 0;
         }
 
         /* use prefetched values */
         rx_desc = next_rxd;
         buffer_info = next_buffer;
     }
     rx_ring->next_to_clean = i;
 
     cleaned_count = E1000_DESC_UNUSED(rx_ring);
     if (cleaned_count)
         adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);
 
     adapter->total_rx_packets += total_rx_packets;
     adapter->total_rx_bytes += total_rx_bytes;
     netdev->stats.rx_bytes += total_rx_bytes;
     netdev->stats.rx_packets += total_rx_packets;
     return cleaned;
 }
 
 /* this should improve performance for small packets with large amounts
  * of reassembly being done in the stack
  */
 static struct sk_buff *e1000_copybreak(struct e1000_adapter *adapter,
                        struct e1000_rx_buffer *buffer_info,
                        u32 length, const void *data)
 {
     struct sk_buff *skb;
 
     if (length > copybreak)
         return NULL;
 
     skb = e1000_alloc_rx_skb(adapter, length);
     if (!skb)
         return NULL;
 
     dma_sync_single_for_cpu(&adapter->pdev->dev, buffer_info->dma,
                 length, DMA_FROM_DEVICE);
 
     skb_put_data(skb, data, length);
 
     return skb;
 }
 
 /**
  * e1000_clean_rx_irq - Send received data up the network stack; legacy
  * @adapter: board private structure
  * @rx_ring: ring to clean
  * @work_done: amount of napi work completed this call
  * @work_to_do: max amount of work allowed for this call to do
  */
 static bool e1000_clean_rx_irq(struct e1000_adapter *adapter,
                    struct e1000_rx_ring *rx_ring,
                    int *work_done, int work_to_do)
 {
     struct net_device *netdev = adapter->netdev;
     struct pci_dev *pdev = adapter->pdev;
     struct e1000_rx_desc *rx_desc, *next_rxd;
     struct e1000_rx_buffer *buffer_info, *next_buffer;
     u32 length;
     unsigned int i;
     int cleaned_count = 0;
     bool cleaned = false;
     unsigned int total_rx_bytes = 0, total_rx_packets = 0;
 
     i = rx_ring->next_to_clean;
     rx_desc = E1000_RX_DESC(*rx_ring, i);
     buffer_info = &rx_ring->buffer_info[i];
 
     while (rx_desc->status & E1000_RXD_STAT_DD) {
         struct sk_buff *skb;
         u8 *data;
         u8 status;
 
         if (*work_done >= work_to_do)
             break;
         (*work_done)++;
         dma_rmb(); /* read descriptor and rx_buffer_info after status DD */
 
         status = rx_desc->status;
         length = le16_to_cpu(rx_desc->length);
 
         data = buffer_info->rxbuf.data;
         prefetch(data);
         skb = e1000_copybreak(adapter, buffer_info, length, data);
         if (!skb) {
             unsigned int frag_len = e1000_frag_len(adapter);
 
             skb = napi_build_skb(data - E1000_HEADROOM, frag_len);
             if (!skb) {
                 adapter->alloc_rx_buff_failed++;
                 break;
             }
 
             skb_reserve(skb, E1000_HEADROOM);
             dma_unmap_single(&pdev->dev, buffer_info->dma,
                      adapter->rx_buffer_len,
                      DMA_FROM_DEVICE);
             buffer_info->dma = 0;
             buffer_info->rxbuf.data = NULL;
         }
 
         if (++i == rx_ring->count)
             i = 0;
 
         next_rxd = E1000_RX_DESC(*rx_ring, i);
         prefetch(next_rxd);
 
         next_buffer = &rx_ring->buffer_info[i];
 
         cleaned = true;
         cleaned_count++;
 
         /* !EOP means multiple descriptors were used to store a single
          * packet, if thats the case we need to toss it.  In fact, we
          * 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(!(status & E1000_RXD_STAT_EOP)))
             adapter->discarding = true;
 
         if (adapter->discarding) {
             /* All receives must fit into a single buffer */
             netdev_dbg(netdev, "Receive packet consumed multiple buffers\n");
             dev_kfree_skb(skb);
             if (status & E1000_RXD_STAT_EOP)
                 adapter->discarding = false;
             goto next_desc;
         }
 
         if (unlikely(rx_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK)) {
             if (e1000_tbi_should_accept(adapter, status,
                             rx_desc->errors,
                             length, data)) {
                 length--;
             } else if (netdev->features & NETIF_F_RXALL) {
                 goto process_skb;
             } else {
                 dev_kfree_skb(skb);
                 goto next_desc;
             }
         }
 
 process_skb:
         total_rx_bytes += (length - 4); /* don't count FCS */
         total_rx_packets++;
 
         if (likely(!(netdev->features & NETIF_F_RXFCS)))
             /* adjust length to remove Ethernet CRC, this must be
              * done after the TBI_ACCEPT workaround above
              */
             length -= 4;
 
         if (buffer_info->rxbuf.data == NULL)
             skb_put(skb, length);
         else /* copybreak skb */
             skb_trim(skb, length);
 
         /* Receive Checksum Offload */
         e1000_rx_checksum(adapter,
                   (u32)(status) |
                   ((u32)(rx_desc->errors) << 24),
                   le16_to_cpu(rx_desc->csum), skb);
 
         e1000_receive_skb(adapter, status, rx_desc->special, skb);
 
 next_desc:
         rx_desc->status = 0;
 
         /* return some buffers to hardware, one at a time is too slow */
         if (unlikely(cleaned_count >= E1000_RX_BUFFER_WRITE)) {
             adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);
             cleaned_count = 0;
         }
 
         /* use prefetched values */
         rx_desc = next_rxd;
         buffer_info = next_buffer;
     }
     rx_ring->next_to_clean = i;
 
     cleaned_count = E1000_DESC_UNUSED(rx_ring);
     if (cleaned_count)
         adapter->alloc_rx_buf(adapter, rx_ring, cleaned_count);
 
     adapter->total_rx_packets += total_rx_packets;
     adapter->total_rx_bytes += total_rx_bytes;
     netdev->stats.rx_bytes += total_rx_bytes;
     netdev->stats.rx_packets += total_rx_packets;
     return cleaned;
 }
 
 /**
  * e1000_alloc_jumbo_rx_buffers - Replace used jumbo receive buffers
  * @adapter: address of board private structure
  * @rx_ring: pointer to receive ring structure
  * @cleaned_count: number of buffers to allocate this pass
  **/
 static void
 e1000_alloc_jumbo_rx_buffers(struct e1000_adapter *adapter,
                  struct e1000_rx_ring *rx_ring, int cleaned_count)
 {
     struct pci_dev *pdev = adapter->pdev;
     struct e1000_rx_desc *rx_desc;
     struct e1000_rx_buffer *buffer_info;
     unsigned int i;
 
     i = rx_ring->next_to_use;
     buffer_info = &rx_ring->buffer_info[i];
 
     while (cleaned_count--) {
         /* allocate a new page if necessary */
         if (!buffer_info->rxbuf.page) {
             buffer_info->rxbuf.page = alloc_page(GFP_ATOMIC);
             if (unlikely(!buffer_info->rxbuf.page)) {
                 adapter->alloc_rx_buff_failed++;
                 break;
             }
         }
 
         if (!buffer_info->dma) {
             buffer_info->dma = dma_map_page(&pdev->dev,
                             buffer_info->rxbuf.page, 0,
                             adapter->rx_buffer_len,
                             DMA_FROM_DEVICE);
             if (dma_mapping_error(&pdev->dev, buffer_info->dma)) {
                 put_page(buffer_info->rxbuf.page);
                 buffer_info->rxbuf.page = NULL;
                 buffer_info->dma = 0;
                 adapter->alloc_rx_buff_failed++;
                 break;
             }
         }
 
         rx_desc = E1000_RX_DESC(*rx_ring, i);
         rx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
 
         if (unlikely(++i == rx_ring->count))
             i = 0;
         buffer_info = &rx_ring->buffer_info[i];
     }
 
     if (likely(rx_ring->next_to_use != i)) {
         rx_ring->next_to_use = i;
         if (unlikely(i-- == 0))
             i = (rx_ring->count - 1);
 
         /* Force memory writes to complete before letting h/w
          * know there are new descriptors to fetch.  (Only
          * applicable for weak-ordered memory model archs,
          * such as IA-64).
          */
         dma_wmb();
         writel(i, adapter->hw.hw_addr + rx_ring->rdt);
     }
 }
 
 /**
  * e1000_alloc_rx_buffers - Replace used receive buffers; legacy & extended
  * @adapter: address of board private structure
  * @rx_ring: pointer to ring struct
  * @cleaned_count: number of new Rx buffers to try to allocate
  **/
 static void e1000_alloc_rx_buffers(struct e1000_adapter *adapter,
                    struct e1000_rx_ring *rx_ring,
                    int cleaned_count)
 {
     struct e1000_hw *hw = &adapter->hw;
     struct pci_dev *pdev = adapter->pdev;
     struct e1000_rx_desc *rx_desc;
     struct e1000_rx_buffer *buffer_info;
     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--) {
         void *data;
 
         if (buffer_info->rxbuf.data)
             goto skip;
 
         data = e1000_alloc_frag(adapter);
         if (!data) {
             /* Better luck next round */
             adapter->alloc_rx_buff_failed++;
             break;
         }
 
         /* Fix for errata 23, can't cross 64kB boundary */
         if (!e1000_check_64k_bound(adapter, data, bufsz)) {
             void *olddata = data;
             e_err(rx_err, "skb align check failed: %u bytes at "
                   "%p\n", bufsz, data);
             /* Try again, without freeing the previous */
             data = e1000_alloc_frag(adapter);
             /* Failed allocation, critical failure */
             if (!data) {
                 skb_free_frag(olddata);
                 adapter->alloc_rx_buff_failed++;
                 break;
             }
 
             if (!e1000_check_64k_bound(adapter, data, bufsz)) {
                 /* give up */
                 skb_free_frag(data);
                 skb_free_frag(olddata);
                 adapter->alloc_rx_buff_failed++;
                 break;
             }
 
             /* Use new allocation */
             skb_free_frag(olddata);
         }
         buffer_info->dma = dma_map_single(&pdev->dev,
                           data,
                           adapter->rx_buffer_len,
                           DMA_FROM_DEVICE);
         if (dma_mapping_error(&pdev->dev, buffer_info->dma)) {
             skb_free_frag(data);
             buffer_info->dma = 0;
             adapter->alloc_rx_buff_failed++;
             break;
         }
 
         /* XXX if it was allocated cleanly it will never map to a
          * boundary crossing
          */
 
         /* Fix for errata 23, can't cross 64kB boundary */
         if (!e1000_check_64k_bound(adapter,
                     (void *)(unsigned long)buffer_info->dma,
                     adapter->rx_buffer_len)) {
             e_err(rx_err, "dma align check failed: %u bytes at "
                   "%p\n", adapter->rx_buffer_len,
                   (void *)(unsigned long)buffer_info->dma);
 
             dma_unmap_single(&pdev->dev, buffer_info->dma,
                      adapter->rx_buffer_len,
                      DMA_FROM_DEVICE);
 
             skb_free_frag(data);
             buffer_info->rxbuf.data = NULL;
             buffer_info->dma = 0;
 
             adapter->alloc_rx_buff_failed++;
             break;
         }
         buffer_info->rxbuf.data = data;
  skip:
         rx_desc = E1000_RX_DESC(*rx_ring, i);
         rx_desc->buffer_addr = cpu_to_le64(buffer_info->dma);
 
         if (unlikely(++i == rx_ring->count))
             i = 0;
         buffer_info = &rx_ring->buffer_info[i];
     }
 
     if (likely(rx_ring->next_to_use != i)) {
         rx_ring->next_to_use = i;
         if (unlikely(i-- == 0))
             i = (rx_ring->count - 1);
 
         /* Force memory writes to complete before letting h/w
          * know there are new descriptors to fetch.  (Only
          * applicable for weak-ordered memory model archs,
          * such as IA-64).
          */
         dma_wmb();
         writel(i, hw->hw_addr + rx_ring->rdt);
     }
 }
 
 /**
  * e1000_smartspeed - Workaround for SmartSpeed on 82541 and 82547 controllers.
  * @adapter: address of board private structure
  **/
 static void e1000_smartspeed(struct e1000_adapter *adapter)
 {
     struct e1000_hw *hw = &adapter->hw;
     u16 phy_status;
     u16 phy_ctrl;
 
     if ((hw->phy_type != e1000_phy_igp) || !hw->autoneg ||
        !(hw->autoneg_advertised & ADVERTISE_1000_FULL))
         return;
 
     if (adapter->smartspeed == 0) {
         /* If Master/Slave config fault is asserted twice,
          * we assume back-to-back
          */
         e1000_read_phy_reg(hw, PHY_1000T_STATUS, &phy_status);
         if (!(phy_status & SR_1000T_MS_CONFIG_FAULT))
             return;
         e1000_read_phy_reg(hw, PHY_1000T_STATUS, &phy_status);
         if (!(phy_status & SR_1000T_MS_CONFIG_FAULT))
             return;
         e1000_read_phy_reg(hw, PHY_1000T_CTRL, &phy_ctrl);
         if (phy_ctrl & CR_1000T_MS_ENABLE) {
             phy_ctrl &= ~CR_1000T_MS_ENABLE;
             e1000_write_phy_reg(hw, PHY_1000T_CTRL,
                         phy_ctrl);
             adapter->smartspeed++;
             if (!e1000_phy_setup_autoneg(hw) &&
                !e1000_read_phy_reg(hw, PHY_CTRL,
                            &phy_ctrl)) {
                 phy_ctrl |= (MII_CR_AUTO_NEG_EN |
                          MII_CR_RESTART_AUTO_NEG);
                 e1000_write_phy_reg(hw, PHY_CTRL,
                             phy_ctrl);
             }
         }
         return;
     } else if (adapter->smartspeed == E1000_SMARTSPEED_DOWNSHIFT) {
         /* If still no link, perhaps using 2/3 pair cable */
         e1000_read_phy_reg(hw, PHY_1000T_CTRL, &phy_ctrl);
         phy_ctrl |= CR_1000T_MS_ENABLE;
         e1000_write_phy_reg(hw, PHY_1000T_CTRL, phy_ctrl);
         if (!e1000_phy_setup_autoneg(hw) &&
            !e1000_read_phy_reg(hw, PHY_CTRL, &phy_ctrl)) {
             phy_ctrl |= (MII_CR_AUTO_NEG_EN |
                      MII_CR_RESTART_AUTO_NEG);
             e1000_write_phy_reg(hw, PHY_CTRL, phy_ctrl);
         }
     }
     /* Restart process after E1000_SMARTSPEED_MAX iterations */
     if (adapter->smartspeed++ == E1000_SMARTSPEED_MAX)
         adapter->smartspeed = 0;
 }
 
 /**
  * e1000_ioctl - handle ioctl calls
  * @netdev: pointer to our netdev
  * @ifr: pointer to interface request structure
  * @cmd: ioctl data
  **/
 static int e1000_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
 {
     switch (cmd) {
     case SIOCGMIIPHY:
     case SIOCGMIIREG:
     case SIOCSMIIREG:
         return e1000_mii_ioctl(netdev, ifr, cmd);
     default:
         return -EOPNOTSUPP;
     }
 }
 
 /**
  * e1000_mii_ioctl -
  * @netdev: pointer to our netdev
  * @ifr: pointer to interface request structure
  * @cmd: ioctl data
  **/
 static int e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr,
                int cmd)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     struct mii_ioctl_data *data = if_mii(ifr);
     int retval;
     u16 mii_reg;
     unsigned long flags;
 
     if (hw->media_type != e1000_media_type_copper)
         return -EOPNOTSUPP;
 
     switch (cmd) {
     case SIOCGMIIPHY:
         data->phy_id = hw->phy_addr;
         break;
     case SIOCGMIIREG:
         spin_lock_irqsave(&adapter->stats_lock, flags);
         if (e1000_read_phy_reg(hw, data->reg_num & 0x1F,
                    &data->val_out)) {
             spin_unlock_irqrestore(&adapter->stats_lock, flags);
             return -EIO;
         }
         spin_unlock_irqrestore(&adapter->stats_lock, flags);
         break;
     case SIOCSMIIREG:
         if (data->reg_num & ~(0x1F))
             return -EFAULT;
         mii_reg = data->val_in;
         spin_lock_irqsave(&adapter->stats_lock, flags);
         if (e1000_write_phy_reg(hw, data->reg_num,
                     mii_reg)) {
             spin_unlock_irqrestore(&adapter->stats_lock, flags);
             return -EIO;
         }
         spin_unlock_irqrestore(&adapter->stats_lock, flags);
         if (hw->media_type == e1000_media_type_copper) {
             switch (data->reg_num) {
             case PHY_CTRL:
                 if (mii_reg & MII_CR_POWER_DOWN)
                     break;
                 if (mii_reg & MII_CR_AUTO_NEG_EN) {
                     hw->autoneg = 1;
                     hw->autoneg_advertised = 0x2F;
                 } else {
                     u32 speed;
                     if (mii_reg & 0x40)
                         speed = SPEED_1000;
                     else if (mii_reg & 0x2000)
                         speed = SPEED_100;
                     else
                         speed = SPEED_10;
                     retval = e1000_set_spd_dplx(
                         adapter, speed,
                         ((mii_reg & 0x100)
                          ? DUPLEX_FULL :
                          DUPLEX_HALF));
                     if (retval)
                         return retval;
                 }
                 if (netif_running(adapter->netdev))
                     e1000_reinit_locked(adapter);
                 else
                     e1000_reset(adapter);
                 break;
             case M88E1000_PHY_SPEC_CTRL:
             case M88E1000_EXT_PHY_SPEC_CTRL:
                 if (e1000_phy_reset(hw))
                     return -EIO;
                 break;
             }
         } else {
             switch (data->reg_num) {
             case PHY_CTRL:
                 if (mii_reg & MII_CR_POWER_DOWN)
                     break;
                 if (netif_running(adapter->netdev))
                     e1000_reinit_locked(adapter);
                 else
                     e1000_reset(adapter);
                 break;
             }
         }
         break;
     default:
         return -EOPNOTSUPP;
     }
     return E1000_SUCCESS;
 }
 
 void e1000_pci_set_mwi(struct e1000_hw *hw)
 {
     struct e1000_adapter *adapter = hw->back;
     int ret_val = pci_set_mwi(adapter->pdev);
 
     if (ret_val)
         e_err(probe, "Error in setting MWI\n");
 }
 
 void e1000_pci_clear_mwi(struct e1000_hw *hw)
 {
     struct e1000_adapter *adapter = hw->back;
 
     pci_clear_mwi(adapter->pdev);
 }
 
 int e1000_pcix_get_mmrbc(struct e1000_hw *hw)
 {
     struct e1000_adapter *adapter = hw->back;
     return pcix_get_mmrbc(adapter->pdev);
 }
 
 void e1000_pcix_set_mmrbc(struct e1000_hw *hw, int mmrbc)
 {
     struct e1000_adapter *adapter = hw->back;
     pcix_set_mmrbc(adapter->pdev, mmrbc);
 }
 
 void e1000_io_write(struct e1000_hw *hw, unsigned long port, u32 value)
 {
     outl(value, port);
 }
 
 static bool e1000_vlan_used(struct e1000_adapter *adapter)
 {
     u16 vid;
 
     for_each_set_bit(vid, adapter->active_vlans, VLAN_N_VID)
         return true;
     return false;
 }
 
 static void __e1000_vlan_mode(struct e1000_adapter *adapter,
                   netdev_features_t features)
 {
     struct e1000_hw *hw = &adapter->hw;
     u32 ctrl;
 
     ctrl = er32(CTRL);
     if (features & NETIF_F_HW_VLAN_CTAG_RX) {
         /* enable VLAN tag insert/strip */
         ctrl |= E1000_CTRL_VME;
     } else {
         /* disable VLAN tag insert/strip */
         ctrl &= ~E1000_CTRL_VME;
     }
     ew32(CTRL, ctrl);
 }
 static void e1000_vlan_filter_on_off(struct e1000_adapter *adapter,
                      bool filter_on)
 {
     struct e1000_hw *hw = &adapter->hw;
     u32 rctl;
 
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         e1000_irq_disable(adapter);
 
     __e1000_vlan_mode(adapter, adapter->netdev->features);
     if (filter_on) {
         /* enable VLAN receive filtering */
         rctl = er32(RCTL);
         rctl &= ~E1000_RCTL_CFIEN;
         if (!(adapter->netdev->flags & IFF_PROMISC))
             rctl |= E1000_RCTL_VFE;
         ew32(RCTL, rctl);
         e1000_update_mng_vlan(adapter);
     } else {
         /* disable VLAN receive filtering */
         rctl = er32(RCTL);
         rctl &= ~E1000_RCTL_VFE;
         ew32(RCTL, rctl);
     }
 
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         e1000_irq_enable(adapter);
 }
 
 static void e1000_vlan_mode(struct net_device *netdev,
                 netdev_features_t features)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
 
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         e1000_irq_disable(adapter);
 
     __e1000_vlan_mode(adapter, features);
 
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         e1000_irq_enable(adapter);
 }
 
 static int e1000_vlan_rx_add_vid(struct net_device *netdev,
                  __be16 proto, u16 vid)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     u32 vfta, index;
 
     if ((hw->mng_cookie.status &
          E1000_MNG_DHCP_COOKIE_STATUS_VLAN_SUPPORT) &&
         (vid == adapter->mng_vlan_id))
         return 0;
 
     if (!e1000_vlan_used(adapter))
         e1000_vlan_filter_on_off(adapter, true);
 
     /* add VID to filter table */
     index = (vid >> 5) & 0x7F;
     vfta = E1000_READ_REG_ARRAY(hw, VFTA, index);
     vfta |= (1 << (vid & 0x1F));
     e1000_write_vfta(hw, index, vfta);
 
     set_bit(vid, adapter->active_vlans);
 
     return 0;
 }
 
 static int e1000_vlan_rx_kill_vid(struct net_device *netdev,
                   __be16 proto, u16 vid)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     u32 vfta, index;
 
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         e1000_irq_disable(adapter);
     if (!test_bit(__E1000_DOWN, &adapter->flags))
         e1000_irq_enable(adapter);
 
     /* remove VID from filter table */
     index = (vid >> 5) & 0x7F;
     vfta = E1000_READ_REG_ARRAY(hw, VFTA, index);
     vfta &= ~(1 << (vid & 0x1F));
     e1000_write_vfta(hw, index, vfta);
 
     clear_bit(vid, adapter->active_vlans);
 
     if (!e1000_vlan_used(adapter))
         e1000_vlan_filter_on_off(adapter, false);
 
     return 0;
 }
 
 static void e1000_restore_vlan(struct e1000_adapter *adapter)
 {
     u16 vid;
 
     if (!e1000_vlan_used(adapter))
         return;
 
     e1000_vlan_filter_on_off(adapter, true);
     for_each_set_bit(vid, adapter->active_vlans, VLAN_N_VID)
         e1000_vlan_rx_add_vid(adapter->netdev, htons(ETH_P_8021Q), vid);
 }
 
 int e1000_set_spd_dplx(struct e1000_adapter *adapter, u32 spd, u8 dplx)
 {
     struct e1000_hw *hw = &adapter->hw;
 
     hw->autoneg = 0;
 
     /* Make sure dplx is at most 1 bit and lsb of speed is not set
      * for the switch() below to work
      */
     if ((spd & 1) || (dplx & ~1))
         goto err_inval;
 
     /* Fiber NICs only allow 1000 gbps Full duplex */
     if ((hw->media_type == e1000_media_type_fiber) &&
         spd != SPEED_1000 &&
         dplx != DUPLEX_FULL)
         goto err_inval;
 
     switch (spd + dplx) {
     case SPEED_10 + DUPLEX_HALF:
         hw->forced_speed_duplex = e1000_10_half;
         break;
     case SPEED_10 + DUPLEX_FULL:
         hw->forced_speed_duplex = e1000_10_full;
         break;
     case SPEED_100 + DUPLEX_HALF:
         hw->forced_speed_duplex = e1000_100_half;
         break;
     case SPEED_100 + DUPLEX_FULL:
         hw->forced_speed_duplex = e1000_100_full;
         break;
     case SPEED_1000 + DUPLEX_FULL:
         hw->autoneg = 1;
         hw->autoneg_advertised = ADVERTISE_1000_FULL;
         break;
     case SPEED_1000 + DUPLEX_HALF: /* not supported */
     default:
         goto err_inval;
     }
 
     /* clear MDI, MDI(-X) override is only allowed when autoneg enabled */
     hw->mdix = AUTO_ALL_MODES;
 
     return 0;
 
 err_inval:
     e_err(probe, "Unsupported Speed/Duplex configuration\n");
     return -EINVAL;
 }
 
 static int __e1000_shutdown(struct pci_dev *pdev, bool *enable_wake)
 {
     struct net_device *netdev = pci_get_drvdata(pdev);
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     u32 ctrl, ctrl_ext, rctl, status;
     u32 wufc = adapter->wol;
 
     netif_device_detach(netdev);
 
     if (netif_running(netdev)) {
         int count = E1000_CHECK_RESET_COUNT;
 
         while (test_bit(__E1000_RESETTING, &adapter->flags) && count--)
             usleep_range(10000, 20000);
 
         WARN_ON(test_bit(__E1000_RESETTING, &adapter->flags));
         e1000_down(adapter);
     }
 
     status = er32(STATUS);
     if (status & E1000_STATUS_LU)
         wufc &= ~E1000_WUFC_LNKC;
 
     if (wufc) {
         e1000_setup_rctl(adapter);
         e1000_set_rx_mode(netdev);
 
         rctl = er32(RCTL);
 
         /* turn on all-multi mode if wake on multicast is enabled */
         if (wufc & E1000_WUFC_MC)
             rctl |= E1000_RCTL_MPE;
 
         /* enable receives in the hardware */
         ew32(RCTL, rctl | E1000_RCTL_EN);
 
         if (hw->mac_type >= e1000_82540) {
             ctrl = er32(CTRL);
             /* advertise wake from D3Cold */
             #define E1000_CTRL_ADVD3WUC 0x00100000
             /* phy power management enable */
             #define E1000_CTRL_EN_PHY_PWR_MGMT 0x00200000
             ctrl |= E1000_CTRL_ADVD3WUC |
                 E1000_CTRL_EN_PHY_PWR_MGMT;
             ew32(CTRL, ctrl);
         }
 
         if (hw->media_type == e1000_media_type_fiber ||
             hw->media_type == e1000_media_type_internal_serdes) {
             /* keep the laser running in D3 */
             ctrl_ext = er32(CTRL_EXT);
             ctrl_ext |= E1000_CTRL_EXT_SDP7_DATA;
             ew32(CTRL_EXT, ctrl_ext);
         }
 
         ew32(WUC, E1000_WUC_PME_EN);
         ew32(WUFC, wufc);
     } else {
         ew32(WUC, 0);
         ew32(WUFC, 0);
     }
 
     e1000_release_manageability(adapter);
 
     *enable_wake = !!wufc;
 
     /* make sure adapter isn't asleep if manageability is enabled */
     if (adapter->en_mng_pt)
         *enable_wake = true;
 
     if (netif_running(netdev))
         e1000_free_irq(adapter);
 
     if (!test_and_set_bit(__E1000_DISABLED, &adapter->flags))
         pci_disable_device(pdev);
 
     return 0;
 }
 
 static int __maybe_unused e1000_suspend(struct device *dev)
 {
     int retval;
     struct pci_dev *pdev = to_pci_dev(dev);
     bool wake;
 
     retval = __e1000_shutdown(pdev, &wake);
     device_set_wakeup_enable(dev, wake);
 
     return retval;
 }
 
 static int __maybe_unused e1000_resume(struct device *dev)
 {
     struct pci_dev *pdev = to_pci_dev(dev);
     struct net_device *netdev = pci_get_drvdata(pdev);
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     u32 err;
 
     if (adapter->need_ioport)
         err = pci_enable_device(pdev);
     else
         err = pci_enable_device_mem(pdev);
     if (err) {
         pr_err("Cannot enable PCI device from suspend\n");
         return err;
     }
 
     /* flush memory to make sure state is correct */
     smp_mb__before_atomic();
     clear_bit(__E1000_DISABLED, &adapter->flags);
     pci_set_master(pdev);
 
     pci_enable_wake(pdev, PCI_D3hot, 0);
     pci_enable_wake(pdev, PCI_D3cold, 0);
 
     if (netif_running(netdev)) {
         err = e1000_request_irq(adapter);
         if (err)
             return err;
     }
 
     e1000_power_up_phy(adapter);
     e1000_reset(adapter);
     ew32(WUS, ~0);
 
     e1000_init_manageability(adapter);
 
     if (netif_running(netdev))
         e1000_up(adapter);
 
     netif_device_attach(netdev);
 
     return 0;
 }
 
 static void e1000_shutdown(struct pci_dev *pdev)
 {
     bool wake;
 
     __e1000_shutdown(pdev, &wake);
 
     if (system_state == SYSTEM_POWER_OFF) {
         pci_wake_from_d3(pdev, wake);
         pci_set_power_state(pdev, PCI_D3hot);
     }
 }
 
 #ifdef CONFIG_NET_POLL_CONTROLLER
 /* Polling 'interrupt' - used by things like netconsole to send skbs
  * without having to re-enable interrupts. It's not called while
  * the interrupt routine is executing.
  */
 static void e1000_netpoll(struct net_device *netdev)
 {
     struct e1000_adapter *adapter = netdev_priv(netdev);
 
     if (disable_hardirq(adapter->pdev->irq))
         e1000_intr(adapter->pdev->irq, netdev);
     enable_irq(adapter->pdev->irq);
 }
 #endif
 
 /**
  * e1000_io_error_detected - called when PCI error is detected
  * @pdev: Pointer to PCI device
  * @state: The current pci connection state
  *
  * This function is called after a PCI bus error affecting
  * this device has been detected.
  */
 static pci_ers_result_t e1000_io_error_detected(struct pci_dev *pdev,
                         pci_channel_state_t state)
 {
     struct net_device *netdev = pci_get_drvdata(pdev);
     struct e1000_adapter *adapter = netdev_priv(netdev);
 
     netif_device_detach(netdev);
 
     if (state == pci_channel_io_perm_failure)
         return PCI_ERS_RESULT_DISCONNECT;
 
     if (netif_running(netdev))
         e1000_down(adapter);
 
     if (!test_and_set_bit(__E1000_DISABLED, &adapter->flags))
         pci_disable_device(pdev);
 
     /* Request a slot reset. */
     return PCI_ERS_RESULT_NEED_RESET;
 }
 
 /**
  * e1000_io_slot_reset - called after the pci bus has been reset.
  * @pdev: Pointer to PCI device
  *
  * Restart the card from scratch, as if from a cold-boot. Implementation
  * resembles the first-half of the e1000_resume routine.
  */
 static pci_ers_result_t e1000_io_slot_reset(struct pci_dev *pdev)
 {
     struct net_device *netdev = pci_get_drvdata(pdev);
     struct e1000_adapter *adapter = netdev_priv(netdev);
     struct e1000_hw *hw = &adapter->hw;
     int err;
 
     if (adapter->need_ioport)
         err = pci_enable_device(pdev);
     else
         err = pci_enable_device_mem(pdev);
     if (err) {
         pr_err("Cannot re-enable PCI device after reset.\n");
         return PCI_ERS_RESULT_DISCONNECT;
     }
 
     /* flush memory to make sure state is correct */
     smp_mb__before_atomic();
     clear_bit(__E1000_DISABLED, &adapter->flags);
     pci_set_master(pdev);
 
     pci_enable_wake(pdev, PCI_D3hot, 0);
     pci_enable_wake(pdev, PCI_D3cold, 0);
 
     e1000_reset(adapter);
     ew32(WUS, ~0);
 
     return PCI_ERS_RESULT_RECOVERED;
 }
 
 /**
  * e1000_io_resume - called when traffic can start flowing again.
  * @pdev: Pointer to PCI device
  *
  * This callback is called when the error recovery driver tells us that
  * its OK to resume normal operation. Implementation resembles the
  * second-half of the e1000_resume routine.
  */
 static void e1000_io_resume(struct pci_dev *pdev)
 {
     struct net_device *netdev = pci_get_drvdata(pdev);
     struct e1000_adapter *adapter = netdev_priv(netdev);
 
     e1000_init_manageability(adapter);
 
     if (netif_running(netdev)) {
         if (e1000_up(adapter)) {
             pr_info("can't bring device back up after reset\n");
             return;
         }
     }
 
     netif_device_attach(netdev);
 }
 
 /* e1000_main.c */