path: root/sys/dev/pci/if_em_hw.c

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

  Copyright (c) 2001-2003, Intel Corporation 
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without 
  modification, are permitted provided that the following conditions are met:
  
   1. Redistributions of source code must retain the above copyright notice, 
      this list of conditions and the following disclaimer.
  
   2. Redistributions in binary form must reproduce the above copyright 
      notice, this list of conditions and the following disclaimer in the 
      documentation and/or other materials provided with the distribution.
  
   3. Neither the name of the Intel Corporation nor the names of its 
      contributors may be used to endorse or promote products derived from 
      this software without specific prior written permission.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  POSSIBILITY OF SUCH DAMAGE.

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

/* $FreeBSD: if_em_hw.c,v 1.12 2003/11/14 18:02:24 pdeuskar Exp $ */
/* $OpenBSD: if_em_hw.c,v 1.3 2003/12/09 23:37:03 henning Exp $ */
/* if_em_hw.c
 * Shared functions for accessing and configuring the MAC
 */
 
#include "bpfilter.h"
#include "vlan.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/socket.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/if_ether.h>
#endif

#if NVLAN > 0
#include <net/if_types.h>
#include <net/if_vlan_var.h>
#endif

#if NBPFILTER > 0
#include <net/bpf.h>
#endif

#include <uvm/uvm_extern.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcidevs.h>

#include <dev/pci/if_em_hw.h>

static int32_t em_set_phy_type(struct em_hw *hw);
static void em_phy_init_script(struct em_hw *hw);
static int32_t em_setup_copper_link(struct em_hw *hw);
static int32_t em_setup_fiber_serdes_link(struct em_hw *hw);
static int32_t em_adjust_serdes_amplitude(struct em_hw *hw);
static int32_t em_phy_force_speed_duplex(struct em_hw *hw);
static int32_t em_config_mac_to_phy(struct em_hw *hw);
static void em_raise_mdi_clk(struct em_hw *hw, uint32_t *ctrl);
static void em_lower_mdi_clk(struct em_hw *hw, uint32_t *ctrl);
static void em_shift_out_mdi_bits(struct em_hw *hw, uint32_t data,
                                     uint16_t count);
static uint16_t em_shift_in_mdi_bits(struct em_hw *hw);
static int32_t em_phy_reset_dsp(struct em_hw *hw);
static int32_t em_write_eeprom_spi(struct em_hw *hw, uint16_t offset,
                                      uint16_t words, uint16_t *data);
static int32_t em_write_eeprom_microwire(struct em_hw *hw,
                                            uint16_t offset, uint16_t words,
                                            uint16_t *data);
static int32_t em_spi_eeprom_ready(struct em_hw *hw);
static void em_raise_ee_clk(struct em_hw *hw, uint32_t *eecd);
static void em_lower_ee_clk(struct em_hw *hw, uint32_t *eecd);
static void em_shift_out_ee_bits(struct em_hw *hw, uint16_t data,
                                    uint16_t count);
static int32_t em_write_phy_reg_ex(struct em_hw *hw, uint32_t reg_addr,
                                      uint16_t phy_data);
static int32_t em_read_phy_reg_ex(struct em_hw *hw,uint32_t reg_addr,
                                     uint16_t *phy_data);
static uint16_t em_shift_in_ee_bits(struct em_hw *hw, uint16_t count);
static int32_t em_acquire_eeprom(struct em_hw *hw);
static void em_release_eeprom(struct em_hw *hw);
static void em_standby_eeprom(struct em_hw *hw);
static int32_t em_id_led_init(struct em_hw * hw);
static int32_t em_set_vco_speed(struct em_hw *hw);

/* IGP cable length table */
static const
uint16_t em_igp_cable_length_table[IGP01E1000_AGC_LENGTH_TABLE_SIZE] =
    { 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
      5, 10, 10, 10, 10, 10, 10, 10, 20, 20, 20, 20, 20, 25, 25, 25,
      25, 25, 25, 25, 30, 30, 30, 30, 40, 40, 40, 40, 40, 40, 40, 40,
      40, 50, 50, 50, 50, 50, 50, 50, 60, 60, 60, 60, 60, 60, 60, 60,
      60, 70, 70, 70, 70, 70, 70, 80, 80, 80, 80, 80, 80, 90, 90, 90,
      90, 90, 90, 90, 90, 90, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100,
      100, 100, 100, 100, 110, 110, 110, 110, 110, 110, 110, 110, 110, 110, 110, 110,
      110, 110, 110, 110, 110, 110, 120, 120, 120, 120, 120, 120, 120, 120, 120, 120};


/******************************************************************************
 * Set the phy type member in the hw struct.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_set_phy_type(struct em_hw *hw)
{
    DEBUGFUNC("em_set_phy_type");

    switch(hw->phy_id) {
    case M88E1000_E_PHY_ID:
    case M88E1000_I_PHY_ID:
    case M88E1011_I_PHY_ID:
        hw->phy_type = em_phy_m88;
        break;
    case IGP01E1000_I_PHY_ID:
        hw->phy_type = em_phy_igp;
        break;
    default:
        /* Should never have loaded on this device */
        hw->phy_type = em_phy_undefined;
        return -E1000_ERR_PHY_TYPE;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * IGP phy init script - initializes the GbE PHY
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
static void
em_phy_init_script(struct em_hw *hw)
{
    DEBUGFUNC("em_phy_init_script");

    if(hw->phy_init_script) {
        msec_delay(20);

        em_write_phy_reg(hw,0x0000,0x0140);

        msec_delay(5);

        if(hw->mac_type == em_82541 || hw->mac_type == em_82547) {
            em_write_phy_reg(hw, 0x1F95, 0x0001);

            em_write_phy_reg(hw, 0x1F71, 0xBD21);

            em_write_phy_reg(hw, 0x1F79, 0x0018);

            em_write_phy_reg(hw, 0x1F30, 0x1600);

            em_write_phy_reg(hw, 0x1F31, 0x0014);

            em_write_phy_reg(hw, 0x1F32, 0x161C);

            em_write_phy_reg(hw, 0x1F94, 0x0003);

            em_write_phy_reg(hw, 0x1F96, 0x003F);

            em_write_phy_reg(hw, 0x2010, 0x0008);
        } else {
            em_write_phy_reg(hw, 0x1F73, 0x0099);
        }

        em_write_phy_reg(hw, 0x0000, 0x3300);


        if(hw->mac_type == em_82547) {
            uint16_t fused, fine, coarse;

            /* Move to analog registers page */
            em_read_phy_reg(hw, IGP01E1000_ANALOG_SPARE_FUSE_STATUS, &fused);

            if(!(fused & IGP01E1000_ANALOG_SPARE_FUSE_ENABLED)) {
                em_read_phy_reg(hw, IGP01E1000_ANALOG_FUSE_STATUS, &fused);

                fine = fused & IGP01E1000_ANALOG_FUSE_FINE_MASK;
                coarse = fused & IGP01E1000_ANALOG_FUSE_COARSE_MASK;

                if(coarse > IGP01E1000_ANALOG_FUSE_COARSE_THRESH) {
                    coarse -= IGP01E1000_ANALOG_FUSE_COARSE_10;
                    fine -= IGP01E1000_ANALOG_FUSE_FINE_1;
                } else if(coarse == IGP01E1000_ANALOG_FUSE_COARSE_THRESH)
                    fine -= IGP01E1000_ANALOG_FUSE_FINE_10;

                fused = (fused & IGP01E1000_ANALOG_FUSE_POLY_MASK) |
                        (fine & IGP01E1000_ANALOG_FUSE_FINE_MASK) |
                        (coarse & IGP01E1000_ANALOG_FUSE_COARSE_MASK);

                em_write_phy_reg(hw, IGP01E1000_ANALOG_FUSE_CONTROL, fused);
                em_write_phy_reg(hw, IGP01E1000_ANALOG_FUSE_BYPASS,
                                    IGP01E1000_ANALOG_FUSE_ENABLE_SW_CONTROL);
            }
        }
    }
}

/******************************************************************************
 * Set the mac type member in the hw struct.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_set_mac_type(struct em_hw *hw)
{
    DEBUGFUNC("em_set_mac_type");

    switch (hw->device_id) {
    case E1000_DEV_ID_82542:
        switch (hw->revision_id) {
        case E1000_82542_2_0_REV_ID:
            hw->mac_type = em_82542_rev2_0;
            break;
        case E1000_82542_2_1_REV_ID:
            hw->mac_type = em_82542_rev2_1;
            break;
        default:
            /* Invalid 82542 revision ID */
            return -E1000_ERR_MAC_TYPE;
        }
        break;
    case E1000_DEV_ID_82543GC_FIBER:
    case E1000_DEV_ID_82543GC_COPPER:
        hw->mac_type = em_82543;
        break;
    case E1000_DEV_ID_82544EI_COPPER:
    case E1000_DEV_ID_82544EI_FIBER:
    case E1000_DEV_ID_82544GC_COPPER:
    case E1000_DEV_ID_82544GC_LOM:
        hw->mac_type = em_82544;
        break;
    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:
        hw->mac_type = em_82540;
        break;
    case E1000_DEV_ID_82545EM_COPPER:
    case E1000_DEV_ID_82545EM_FIBER:
        hw->mac_type = em_82545;
        break;
    case E1000_DEV_ID_82545GM_COPPER:
    case E1000_DEV_ID_82545GM_FIBER:
    case E1000_DEV_ID_82545GM_SERDES:
        hw->mac_type = em_82545_rev_3;
        break;
    case E1000_DEV_ID_82546EB_COPPER:
    case E1000_DEV_ID_82546EB_FIBER:
    case E1000_DEV_ID_82546EB_QUAD_COPPER:
        hw->mac_type = em_82546;
        break;
    case E1000_DEV_ID_82546GB_COPPER:
    case E1000_DEV_ID_82546GB_FIBER:
    case E1000_DEV_ID_82546GB_SERDES:
        hw->mac_type = em_82546_rev_3;
        break;
    case E1000_DEV_ID_82541EI:
    case E1000_DEV_ID_82541EI_MOBILE:
        hw->mac_type = em_82541;
        break;
    case E1000_DEV_ID_82541ER:
    case E1000_DEV_ID_82541GI:
    case E1000_DEV_ID_82541GI_MOBILE:
        hw->mac_type = em_82541_rev_2;
        break;
    case E1000_DEV_ID_82547EI:
        hw->mac_type = em_82547;
        break;
    case E1000_DEV_ID_82547GI:
        hw->mac_type = em_82547_rev_2;
        break;
    default:
        /* Should never have loaded on this device */
        return -E1000_ERR_MAC_TYPE;
    }

    return E1000_SUCCESS;
}

/*****************************************************************************
 * Set media type and TBI compatibility.
 *
 * hw - Struct containing variables accessed by shared code
 * **************************************************************************/
void
em_set_media_type(struct em_hw *hw)
{
    uint32_t status;

    DEBUGFUNC("em_set_media_type");

    if(hw->mac_type != em_82543) {
        /* tbi_compatibility is only valid on 82543 */
        hw->tbi_compatibility_en = FALSE;
    }

    switch (hw->device_id) {
    case E1000_DEV_ID_82545GM_SERDES:
    case E1000_DEV_ID_82546GB_SERDES:
        hw->media_type = em_media_type_internal_serdes;
        break;
    default:
        if(hw->mac_type >= em_82543) {
            status = E1000_READ_REG(hw, STATUS);
            if(status & E1000_STATUS_TBIMODE) {
                hw->media_type = em_media_type_fiber;
                /* tbi_compatibility not valid on fiber */
                hw->tbi_compatibility_en = FALSE;
            } else {
                hw->media_type = em_media_type_copper;
            }
        } else {
            /* This is an 82542 (fiber only) */
            hw->media_type = em_media_type_fiber;
        }
    }
}

/******************************************************************************
 * Reset the transmit and receive units; mask and clear all interrupts.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_reset_hw(struct em_hw *hw)
{
    uint32_t ctrl;
    uint32_t ctrl_ext;
    uint32_t icr;
    uint32_t manc;
    uint32_t led_ctrl;

    DEBUGFUNC("em_reset_hw");

    /* For 82542 (rev 2.0), disable MWI before issuing a device reset */
    if(hw->mac_type == em_82542_rev2_0) {
        DEBUGOUT("Disabling MWI on 82542 rev 2.0\n");
        em_pci_clear_mwi(hw);
    }

    /* Clear interrupt mask to stop board from generating interrupts */
    DEBUGOUT("Masking off all interrupts\n");
    E1000_WRITE_REG(hw, IMC, 0xffffffff);

    /* Disable the Transmit and Receive units.  Then delay to allow
     * any pending transactions to complete before we hit the MAC with
     * the global reset.
     */
    E1000_WRITE_REG(hw, RCTL, 0);
    E1000_WRITE_REG(hw, TCTL, E1000_TCTL_PSP);
    E1000_WRITE_FLUSH(hw);

    /* The tbi_compatibility_on Flag must be cleared when Rctl is cleared. */
    hw->tbi_compatibility_on = FALSE;

    /* Delay to allow any outstanding PCI transactions to complete before
     * resetting the device
     */
    msec_delay(10);

    ctrl = E1000_READ_REG(hw, CTRL);

    /* Must reset the PHY before resetting the MAC */
    if((hw->mac_type == em_82541) || (hw->mac_type == em_82547)) {
        E1000_WRITE_REG_IO(hw, CTRL, (ctrl | E1000_CTRL_PHY_RST));
        msec_delay(5);
    }

    /* Issue a global reset to the MAC.  This will reset the chip's
     * transmit, receive, DMA, and link units.  It will not effect
     * the current PCI configuration.  The global reset bit is self-
     * clearing, and should clear within a microsecond.
     */
    DEBUGOUT("Issuing a global reset to MAC\n");

    switch(hw->mac_type) {
        case em_82544:
        case em_82540:
        case em_82545:
        case em_82546:
        case em_82541:
        case em_82541_rev_2:
            /* These controllers can't ack the 64-bit write when issuing the
             * reset, so use IO-mapping as a workaround to issue the reset */
            E1000_WRITE_REG_IO(hw, CTRL, (ctrl | E1000_CTRL_RST));
            break;
        case em_82545_rev_3:
        case em_82546_rev_3:
            /* Reset is performed on a shadow of the control register */
            E1000_WRITE_REG(hw, CTRL_DUP, (ctrl | E1000_CTRL_RST));
            break;
        default:
            E1000_WRITE_REG(hw, CTRL, (ctrl | E1000_CTRL_RST));
            break;
    }

    /* After MAC reset, force reload of EEPROM to restore power-on settings to
     * device.  Later controllers reload the EEPROM automatically, so just wait
     * for reload to complete.
     */
    switch(hw->mac_type) {
        case em_82542_rev2_0:
        case em_82542_rev2_1:
        case em_82543:
        case em_82544:
            /* Wait for reset to complete */
            usec_delay(10);
            ctrl_ext = E1000_READ_REG(hw, CTRL_EXT);
            ctrl_ext |= E1000_CTRL_EXT_EE_RST;
            E1000_WRITE_REG(hw, CTRL_EXT, ctrl_ext);
            E1000_WRITE_FLUSH(hw);
            /* Wait for EEPROM reload */
            msec_delay(2);
            break;
        case em_82541:
        case em_82541_rev_2:
        case em_82547:
        case em_82547_rev_2:
            /* Wait for EEPROM reload */
            msec_delay(20);
            break;
        default:
            /* Wait for EEPROM reload (it happens automatically) */
            msec_delay(5);
            break;
    }

    /* Disable HW ARPs on ASF enabled adapters */
    if(hw->mac_type >= em_82540) {
        manc = E1000_READ_REG(hw, MANC);
        manc &= ~(E1000_MANC_ARP_EN);
        E1000_WRITE_REG(hw, MANC, manc);
    }

    if((hw->mac_type == em_82541) || (hw->mac_type == em_82547)) {
        em_phy_init_script(hw);

        /* Configure activity LED after PHY reset */
        led_ctrl = E1000_READ_REG(hw, LEDCTL);
        led_ctrl &= IGP_ACTIVITY_LED_MASK;
        led_ctrl |= (IGP_ACTIVITY_LED_ENABLE | IGP_LED3_MODE);
        E1000_WRITE_REG(hw, LEDCTL, led_ctrl);
    }

    /* Clear interrupt mask to stop board from generating interrupts */
    DEBUGOUT("Masking off all interrupts\n");
    E1000_WRITE_REG(hw, IMC, 0xffffffff);

    /* Clear any pending interrupt events. */
    icr = E1000_READ_REG(hw, ICR);

    /* If MWI was previously enabled, reenable it. */
    if(hw->mac_type == em_82542_rev2_0) {
        if(hw->pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
            em_pci_set_mwi(hw);
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Performs basic configuration of the adapter.
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Assumes that the controller has previously been reset and is in a
 * post-reset uninitialized state. Initializes the receive address registers,
 * multicast table, and VLAN filter table. Calls routines to setup link
 * configuration and flow control settings. Clears all on-chip counters. Leaves
 * the transmit and receive units disabled and uninitialized.
 *****************************************************************************/
int32_t
em_init_hw(struct em_hw *hw)
{
    uint32_t ctrl;
    uint32_t i;
    int32_t ret_val;
    uint16_t pcix_cmd_word;
    uint16_t pcix_stat_hi_word;
    uint16_t cmd_mmrbc;
    uint16_t stat_mmrbc;

    DEBUGFUNC("em_init_hw");

    /* Initialize Identification LED */
    if((ret_val = em_id_led_init(hw))) {
        DEBUGOUT("Error Initializing Identification LED\n");
        return ret_val;
    }

    /* Set the media type and TBI compatibility */
    em_set_media_type(hw);

    /* Disabling VLAN filtering. */
    DEBUGOUT("Initializing the IEEE VLAN\n");
    E1000_WRITE_REG(hw, VET, 0);

    em_clear_vfta(hw);

    /* For 82542 (rev 2.0), disable MWI and put the receiver into reset */
    if(hw->mac_type == em_82542_rev2_0) {
        DEBUGOUT("Disabling MWI on 82542 rev 2.0\n");
        em_pci_clear_mwi(hw);
        E1000_WRITE_REG(hw, RCTL, E1000_RCTL_RST);
        E1000_WRITE_FLUSH(hw);
        msec_delay(5);
    }

    /* Setup the receive address. This involves initializing all of the Receive
     * Address Registers (RARs 0 - 15).
     */
    em_init_rx_addrs(hw);

    /* For 82542 (rev 2.0), take the receiver out of reset and enable MWI */
    if(hw->mac_type == em_82542_rev2_0) {
        E1000_WRITE_REG(hw, RCTL, 0);
        E1000_WRITE_FLUSH(hw);
        msec_delay(1);
        if(hw->pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
            em_pci_set_mwi(hw);
    }

    /* Zero out the Multicast HASH table */
    DEBUGOUT("Zeroing the MTA\n");
    for(i = 0; i < E1000_MC_TBL_SIZE; i++)
        E1000_WRITE_REG_ARRAY(hw, MTA, i, 0);

    /* Set the PCI priority bit correctly in the CTRL register.  This
     * determines if the adapter gives priority to receives, or if it
     * gives equal priority to transmits and receives.
     */
    if(hw->dma_fairness) {
        ctrl = E1000_READ_REG(hw, CTRL);
        E1000_WRITE_REG(hw, CTRL, ctrl | E1000_CTRL_PRIOR);
    }

    switch(hw->mac_type) {
    case em_82545_rev_3:
    case em_82546_rev_3:
        break;
    default:
        /* Workaround for PCI-X problem when BIOS sets MMRBC incorrectly. */
        if(hw->bus_type == em_bus_type_pcix) {
            em_read_pci_cfg(hw, PCIX_COMMAND_REGISTER, &pcix_cmd_word);
            em_read_pci_cfg(hw, PCIX_STATUS_REGISTER_HI,
                &pcix_stat_hi_word);
            cmd_mmrbc = (pcix_cmd_word & PCIX_COMMAND_MMRBC_MASK) >>
                PCIX_COMMAND_MMRBC_SHIFT;
            stat_mmrbc = (pcix_stat_hi_word & PCIX_STATUS_HI_MMRBC_MASK) >>
                PCIX_STATUS_HI_MMRBC_SHIFT;
            if(stat_mmrbc == PCIX_STATUS_HI_MMRBC_4K)
                stat_mmrbc = PCIX_STATUS_HI_MMRBC_2K;
            if(cmd_mmrbc > stat_mmrbc) {
                pcix_cmd_word &= ~PCIX_COMMAND_MMRBC_MASK;
                pcix_cmd_word |= stat_mmrbc << PCIX_COMMAND_MMRBC_SHIFT;
                em_write_pci_cfg(hw, PCIX_COMMAND_REGISTER,
                    &pcix_cmd_word);
            }
        }
        break;
    }

    /* Call a subroutine to configure the link and setup flow control. */
    ret_val = em_setup_link(hw);

    /* Set the transmit descriptor write-back policy */
    if(hw->mac_type > em_82544) {
        ctrl = E1000_READ_REG(hw, TXDCTL);
        ctrl = (ctrl & ~E1000_TXDCTL_WTHRESH) | E1000_TXDCTL_FULL_TX_DESC_WB;
        E1000_WRITE_REG(hw, TXDCTL, ctrl);
    }

    /* Clear all of the statistics registers (clear on read).  It is
     * important that we do this after we have tried to establish link
     * because the symbol error count will increment wildly if there
     * is no link.
     */
    em_clear_hw_cntrs(hw);

    return ret_val;
}

/******************************************************************************
 * Adjust SERDES output amplitude based on EEPROM setting.
 *
 * hw - Struct containing variables accessed by shared code.
 *****************************************************************************/
static int32_t
em_adjust_serdes_amplitude(struct em_hw *hw)
{
    uint16_t eeprom_data;
    int32_t  ret_val;

    DEBUGFUNC("em_adjust_serdes_amplitude");

    if(hw->media_type != em_media_type_internal_serdes)
        return E1000_SUCCESS;

    switch(hw->mac_type) {
    case em_82545_rev_3:
    case em_82546_rev_3:
        break;
    default:
        return E1000_SUCCESS;
    }

    if ((ret_val = em_read_eeprom(hw, EEPROM_SERDES_AMPLITUDE, 1,
                                     &eeprom_data))) {
        return ret_val;
    }

    if(eeprom_data != EEPROM_RESERVED_WORD) {
        /* Adjust SERDES output amplitude only. */
        eeprom_data &= EEPROM_SERDES_AMPLITUDE_MASK; 
        if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_EXT_CTRL,
                                          eeprom_data)))
            return ret_val;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Configures flow control and link settings.
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Determines which flow control settings to use. Calls the apropriate media-
 * specific link configuration function. Configures the flow control settings.
 * Assuming the adapter has a valid link partner, a valid link should be
 * established. Assumes the hardware has previously been reset and the
 * transmitter and receiver are not enabled.
 *****************************************************************************/
int32_t
em_setup_link(struct em_hw *hw)
{
    uint32_t ctrl_ext;
    int32_t ret_val;
    uint16_t eeprom_data;

    DEBUGFUNC("em_setup_link");

    /* Read and store word 0x0F of the EEPROM. This word contains bits
     * that determine the hardware's default PAUSE (flow control) mode,
     * a bit that determines whether the HW defaults to enabling or
     * disabling auto-negotiation, and the direction of the
     * SW defined pins. If there is no SW over-ride of the flow
     * control setting, then the variable hw->fc will
     * be initialized based on a value in the EEPROM.
     */
    if(em_read_eeprom(hw, EEPROM_INIT_CONTROL2_REG, 1, &eeprom_data) < 0) {
        DEBUGOUT("EEPROM Read Error\n");
        return -E1000_ERR_EEPROM;
    }

    if(hw->fc == em_fc_default) {
        if((eeprom_data & EEPROM_WORD0F_PAUSE_MASK) == 0)
            hw->fc = em_fc_none;
        else if((eeprom_data & EEPROM_WORD0F_PAUSE_MASK) ==
                EEPROM_WORD0F_ASM_DIR)
            hw->fc = em_fc_tx_pause;
        else
            hw->fc = em_fc_full;
    }

    /* We want to save off the original Flow Control configuration just
     * in case we get disconnected and then reconnected into a different
     * hub or switch with different Flow Control capabilities.
     */
    if(hw->mac_type == em_82542_rev2_0)
        hw->fc &= (~em_fc_tx_pause);

    if((hw->mac_type < em_82543) && (hw->report_tx_early == 1))
        hw->fc &= (~em_fc_rx_pause);

    hw->original_fc = hw->fc;

    DEBUGOUT1("After fix-ups FlowControl is now = %x\n", hw->fc);

    /* Take the 4 bits from EEPROM word 0x0F that determine the initial
     * polarity value for the SW controlled pins, and setup the
     * Extended Device Control reg with that info.
     * This is needed because one of the SW controlled pins is used for
     * signal detection.  So this should be done before em_setup_pcs_link()
     * or em_phy_setup() is called.
     */
    if(hw->mac_type == em_82543) {
        ctrl_ext = ((eeprom_data & EEPROM_WORD0F_SWPDIO_EXT) <<
                    SWDPIO__EXT_SHIFT);
        E1000_WRITE_REG(hw, CTRL_EXT, ctrl_ext);
    }

    /* Call the necessary subroutine to configure the link. */
    ret_val = (hw->media_type == em_media_type_copper) ?
              em_setup_copper_link(hw) :
              em_setup_fiber_serdes_link(hw);

    /* Initialize the flow control address, type, and PAUSE timer
     * registers to their default values.  This is done even if flow
     * control is disabled, because it does not hurt anything to
     * initialize these registers.
     */
    DEBUGOUT("Initializing the Flow Control address, type and timer regs\n");

    E1000_WRITE_REG(hw, FCAL, FLOW_CONTROL_ADDRESS_LOW);
    E1000_WRITE_REG(hw, FCAH, FLOW_CONTROL_ADDRESS_HIGH);
    E1000_WRITE_REG(hw, FCT, FLOW_CONTROL_TYPE);
    E1000_WRITE_REG(hw, FCTTV, hw->fc_pause_time);

    /* Set the flow control receive threshold registers.  Normally,
     * these registers will be set to a default threshold that may be
     * adjusted later by the driver's runtime code.  However, if the
     * ability to transmit pause frames in not enabled, then these
     * registers will be set to 0.
     */
    if(!(hw->fc & em_fc_tx_pause)) {
        E1000_WRITE_REG(hw, FCRTL, 0);
        E1000_WRITE_REG(hw, FCRTH, 0);
    } else {
        /* We need to set up the Receive Threshold high and low water marks
         * as well as (optionally) enabling the transmission of XON frames.
         */
        if(hw->fc_send_xon) {
            E1000_WRITE_REG(hw, FCRTL, (hw->fc_low_water | E1000_FCRTL_XONE));
            E1000_WRITE_REG(hw, FCRTH, hw->fc_high_water);
        } else {
            E1000_WRITE_REG(hw, FCRTL, hw->fc_low_water);
            E1000_WRITE_REG(hw, FCRTH, hw->fc_high_water);
        }
    }
    return ret_val;
}

/******************************************************************************
 * Sets up link for a fiber based or serdes based adapter
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Manipulates Physical Coding Sublayer functions in order to configure
 * link. Assumes the hardware has been previously reset and the transmitter
 * and receiver are not enabled.
 *****************************************************************************/
static int32_t
em_setup_fiber_serdes_link(struct em_hw *hw)
{
    uint32_t ctrl;
    uint32_t status;
    uint32_t txcw = 0;
    uint32_t i;
    uint32_t signal = 0;
    int32_t ret_val;

    DEBUGFUNC("em_setup_fiber_serdes_link");

    /* On adapters with a MAC newer than 82544, SW Defineable pin 1 will be
     * set when the optics detect a signal. On older adapters, it will be
     * cleared when there is a signal.  This applies to fiber media only.
     * If we're on serdes media, adjust the output amplitude to value set in
     * the EEPROM.
     */
    ctrl = E1000_READ_REG(hw, CTRL);
    if(hw->media_type == em_media_type_fiber)
        signal = (hw->mac_type > em_82544) ? E1000_CTRL_SWDPIN1 : 0;

    if((ret_val = em_adjust_serdes_amplitude(hw)))
        return ret_val;

    /* Take the link out of reset */
    ctrl &= ~(E1000_CTRL_LRST);

    /* Adjust VCO speed to improve BER performance */
    if((ret_val = em_set_vco_speed(hw)))
        return ret_val;

    em_config_collision_dist(hw);

    /* Check for a software override of the flow control settings, and setup
     * the device accordingly.  If auto-negotiation is enabled, then software
     * will have to set the "PAUSE" bits to the correct value in the Tranmsit
     * Config Word Register (TXCW) and re-start auto-negotiation.  However, if
     * auto-negotiation is disabled, then software will have to manually
     * configure the two flow control enable bits in the CTRL register.
     *
     * The possible values of the "fc" parameter are:
     *      0:  Flow control is completely disabled
     *      1:  Rx flow control is enabled (we can receive pause frames, but
     *          not send pause frames).
     *      2:  Tx flow control is enabled (we can send pause frames but we do
     *          not support receiving pause frames).
     *      3:  Both Rx and TX flow control (symmetric) are enabled.
     */
    switch (hw->fc) {
    case em_fc_none:
        /* Flow control is completely disabled by a software over-ride. */
        txcw = (E1000_TXCW_ANE | E1000_TXCW_FD);
        break;
    case em_fc_rx_pause:
        /* RX Flow control is enabled and TX Flow control is disabled by a
         * software over-ride. Since there really isn't a way to advertise
         * that we are capable of RX Pause ONLY, we will advertise that we
         * support both symmetric and asymmetric RX PAUSE. Later, we will
         *  disable the adapter's ability to send PAUSE frames.
         */
        txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_PAUSE_MASK);
        break;
    case em_fc_tx_pause:
        /* TX Flow control is enabled, and RX Flow control is disabled, by a
         * software over-ride.
         */
        txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_ASM_DIR);
        break;
    case em_fc_full:
        /* Flow control (both RX and TX) is enabled by a software over-ride. */
        txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_PAUSE_MASK);
        break;
    default:
        DEBUGOUT("Flow control param set incorrectly\n");
        return -E1000_ERR_CONFIG;
        break;
    }

    /* Since auto-negotiation is enabled, take the link out of reset (the link
     * will be in reset, because we previously reset the chip). This will
     * restart auto-negotiation.  If auto-neogtiation is successful then the
     * link-up status bit will be set and the flow control enable bits (RFCE
     * and TFCE) will be set according to their negotiated value.
     */
    DEBUGOUT("Auto-negotiation enabled\n");

    E1000_WRITE_REG(hw, TXCW, txcw);
    E1000_WRITE_REG(hw, CTRL, ctrl);
    E1000_WRITE_FLUSH(hw);

    hw->txcw = txcw;
    msec_delay(1);

    /* If we have a signal (the cable is plugged in) then poll for a "Link-Up"
     * indication in the Device Status Register.  Time-out if a link isn't
     * seen in 500 milliseconds seconds (Auto-negotiation should complete in
     * less than 500 milliseconds even if the other end is doing it in SW).
     * For internal serdes, we just assume a signal is present, then poll.
     */
    if(hw->media_type == em_media_type_internal_serdes ||
       (E1000_READ_REG(hw, CTRL) & E1000_CTRL_SWDPIN1) == signal) {
        DEBUGOUT("Looking for Link\n");
        for(i = 0; i < (LINK_UP_TIMEOUT / 10); i++) {
            msec_delay(10);
            status = E1000_READ_REG(hw, STATUS);
            if(status & E1000_STATUS_LU) break;
        }
        if(i == (LINK_UP_TIMEOUT / 10)) {
            DEBUGOUT("Never got a valid link from auto-neg!!!\n");
            hw->autoneg_failed = 1;
            /* AutoNeg failed to achieve a link, so we'll call
             * em_check_for_link. This routine will force the link up if
             * we detect a signal. This will allow us to communicate with
             * non-autonegotiating link partners.
             */
            if((ret_val = em_check_for_link(hw))) {
                DEBUGOUT("Error while checking for link\n");
                return ret_val;
            }
            hw->autoneg_failed = 0;
        } else {
            hw->autoneg_failed = 0;
            DEBUGOUT("Valid Link Found\n");
        }
    } else {
        DEBUGOUT("No Signal Detected\n");
    }
    return E1000_SUCCESS;
}

/******************************************************************************
* Detects which PHY is present and the speed and duplex
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
static int32_t
em_setup_copper_link(struct em_hw *hw)
{
    uint32_t ctrl;
    uint32_t led_ctrl;
    int32_t ret_val;
    uint16_t i;
    uint16_t phy_data;

    DEBUGFUNC("em_setup_copper_link");

    ctrl = E1000_READ_REG(hw, CTRL);
    /* With 82543, we need to force speed and duplex on the MAC equal to what
     * the PHY speed and duplex configuration is. In addition, we need to
     * perform a hardware reset on the PHY to take it out of reset.
     */
    if(hw->mac_type > em_82543) {
        ctrl |= E1000_CTRL_SLU;
        ctrl &= ~(E1000_CTRL_FRCSPD | E1000_CTRL_FRCDPX);
        E1000_WRITE_REG(hw, CTRL, ctrl);
    } else {
        ctrl |= (E1000_CTRL_FRCSPD | E1000_CTRL_FRCDPX | E1000_CTRL_SLU);
        E1000_WRITE_REG(hw, CTRL, ctrl);
        em_phy_hw_reset(hw);
    }

    /* Make sure we have a valid PHY */
    if((ret_val = em_detect_gig_phy(hw))) {
        DEBUGOUT("Error, did not detect valid phy.\n");
        return ret_val;
    }
    DEBUGOUT1("Phy ID = %x \n", hw->phy_id);

    if(hw->mac_type <= em_82543 ||
       hw->mac_type == em_82541 || hw->mac_type == em_82547 ||
       hw->mac_type == em_82541_rev_2 || hw->mac_type == em_82547_rev_2)
        hw->phy_reset_disable = FALSE;

    if(!hw->phy_reset_disable) {
        if (hw->phy_type == em_phy_igp) {

            if((ret_val = em_phy_reset(hw))) {
                DEBUGOUT("Error Resetting the PHY\n");
                return ret_val;
            }

            /* Wait 10ms for MAC to configure PHY from eeprom settings */
            msec_delay(15);

            /* Configure activity LED after PHY reset */
            led_ctrl = E1000_READ_REG(hw, LEDCTL);
            led_ctrl &= IGP_ACTIVITY_LED_MASK;
            led_ctrl |= (IGP_ACTIVITY_LED_ENABLE | IGP_LED3_MODE);
            E1000_WRITE_REG(hw, LEDCTL, led_ctrl);

            /* disable lplu d3 during driver init */
            if((ret_val = em_set_d3_lplu_state(hw, FALSE))) {
                DEBUGOUT("Error Disabling LPLU D3\n");
                return ret_val;
            }

            /* Configure mdi-mdix settings */
            if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_CTRL,
                                             &phy_data)))
                return ret_val;

            if((hw->mac_type == em_82541) || (hw->mac_type == em_82547)) {
                hw->dsp_config_state = em_dsp_config_disabled;
                /* Force MDI for IGP B-0 PHY */
                phy_data &= ~(IGP01E1000_PSCR_AUTO_MDIX |
                              IGP01E1000_PSCR_FORCE_MDI_MDIX);
                hw->mdix = 1;

            } else {
                hw->dsp_config_state = em_dsp_config_enabled;
                phy_data &= ~IGP01E1000_PSCR_AUTO_MDIX;

                switch (hw->mdix) {
                case 1:
                    phy_data &= ~IGP01E1000_PSCR_FORCE_MDI_MDIX;
                    break;
                case 2:
                    phy_data |= IGP01E1000_PSCR_FORCE_MDI_MDIX;
                    break;
                case 0:
                default:
                    phy_data |= IGP01E1000_PSCR_AUTO_MDIX;
                    break;
                }
            }
            if((ret_val = em_write_phy_reg(hw, IGP01E1000_PHY_PORT_CTRL,
                                              phy_data)))
                return ret_val;

            /* set auto-master slave resolution settings */
            if(hw->autoneg) {
                em_ms_type phy_ms_setting = hw->master_slave;

                if(hw->ffe_config_state == em_ffe_config_active)
                    hw->ffe_config_state = em_ffe_config_enabled;

                if(hw->dsp_config_state == em_dsp_config_activated)
                    hw->dsp_config_state = em_dsp_config_enabled;

                /* when autonegotiation advertisment is only 1000Mbps then we
                 * should disable SmartSpeed and enable Auto MasterSlave
                 * resolution as hardware default. */
                if(hw->autoneg_advertised == ADVERTISE_1000_FULL) {
                    /* Disable SmartSpeed */
                    if((ret_val = em_read_phy_reg(hw,
                                                    IGP01E1000_PHY_PORT_CONFIG,
                                                    &phy_data)))
                        return ret_val;
                    phy_data &= ~IGP01E1000_PSCFR_SMART_SPEED;
                    if((ret_val = em_write_phy_reg(hw,
                                                     IGP01E1000_PHY_PORT_CONFIG,
                                                     phy_data)))
                        return ret_val;
                    /* Set auto Master/Slave resolution process */
                    if((ret_val = em_read_phy_reg(hw, PHY_1000T_CTRL,
                                                     &phy_data)))
                        return ret_val;
                    phy_data &= ~CR_1000T_MS_ENABLE;
                    if((ret_val = em_write_phy_reg(hw, PHY_1000T_CTRL,
                                                      phy_data)))
                        return ret_val;
                }

                if((ret_val = em_read_phy_reg(hw, PHY_1000T_CTRL,
                                                 &phy_data)))
                    return ret_val;

                /* load defaults for future use */
                hw->original_master_slave = (phy_data & CR_1000T_MS_ENABLE) ?
                                            ((phy_data & CR_1000T_MS_VALUE) ?
                                             em_ms_force_master :
                                             em_ms_force_slave) :
                                             em_ms_auto;

                switch (phy_ms_setting) {
                case em_ms_force_master:
                    phy_data |= (CR_1000T_MS_ENABLE | CR_1000T_MS_VALUE);
                    break;
                case em_ms_force_slave:
                    phy_data |= CR_1000T_MS_ENABLE;
                    phy_data &= ~(CR_1000T_MS_VALUE);
                    break;
                case em_ms_auto:
                    phy_data &= ~CR_1000T_MS_ENABLE;
                default:
                    break;
                }
                if((ret_val = em_write_phy_reg(hw, PHY_1000T_CTRL,
                                                  phy_data)))
                    return ret_val;
            }
        } else {
            /* Enable CRS on TX. This must be set for half-duplex operation. */
            if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_CTRL,
                                             &phy_data)))
                return ret_val;

            phy_data |= M88E1000_PSCR_ASSERT_CRS_ON_TX;

            /* Options:
             *   MDI/MDI-X = 0 (default)
             *   0 - Auto for all speeds
             *   1 - MDI mode
             *   2 - MDI-X mode
             *   3 - Auto for 1000Base-T only (MDI-X for 10/100Base-T modes)
             */
            phy_data &= ~M88E1000_PSCR_AUTO_X_MODE;

            switch (hw->mdix) {
            case 1:
                phy_data |= M88E1000_PSCR_MDI_MANUAL_MODE;
                break;
            case 2:
                phy_data |= M88E1000_PSCR_MDIX_MANUAL_MODE;
                break;
            case 3:
                phy_data |= M88E1000_PSCR_AUTO_X_1000T;
                break;
            case 0:
            default:
                phy_data |= M88E1000_PSCR_AUTO_X_MODE;
                break;
            }

            /* Options:
             *   disable_polarity_correction = 0 (default)
             *       Automatic Correction for Reversed Cable Polarity
             *   0 - Disabled
             *   1 - Enabled
             */
            phy_data &= ~M88E1000_PSCR_POLARITY_REVERSAL;
            if(hw->disable_polarity_correction == 1)
                phy_data |= M88E1000_PSCR_POLARITY_REVERSAL;
            if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_SPEC_CTRL,
                                              phy_data)))
                return ret_val;

            /* Force TX_CLK in the Extended PHY Specific Control Register
             * to 25MHz clock.
             */
            if((ret_val = em_read_phy_reg(hw, M88E1000_EXT_PHY_SPEC_CTRL,
                                             &phy_data)))
                return ret_val;

            phy_data |= M88E1000_EPSCR_TX_CLK_25;

            if (hw->phy_revision < M88E1011_I_REV_4) {
                /* Configure Master and Slave downshift values */
                phy_data &= ~(M88E1000_EPSCR_MASTER_DOWNSHIFT_MASK |
                              M88E1000_EPSCR_SLAVE_DOWNSHIFT_MASK);
                phy_data |= (M88E1000_EPSCR_MASTER_DOWNSHIFT_1X |
                             M88E1000_EPSCR_SLAVE_DOWNSHIFT_1X);
                if((ret_val = em_write_phy_reg(hw,
                                                  M88E1000_EXT_PHY_SPEC_CTRL,
                                                  phy_data)))
                    return ret_val;
            }

            /* SW Reset the PHY so all changes take effect */
            if((ret_val = em_phy_reset(hw))) {
                DEBUGOUT("Error Resetting the PHY\n");
                return ret_val;
            }
        }

        /* Options:
         *   autoneg = 1 (default)
         *      PHY will advertise value(s) parsed from
         *      autoneg_advertised and fc
         *   autoneg = 0
         *      PHY will be set to 10H, 10F, 100H, or 100F
         *      depending on value parsed from forced_speed_duplex.
         */

        /* Is autoneg enabled?  This is enabled by default or by software
         * override.  If so, call em_phy_setup_autoneg routine to parse the
         * autoneg_advertised and fc options. If autoneg is NOT enabled, then
         * the user should have provided a speed/duplex override.  If so, then
         * call em_phy_force_speed_duplex to parse and set this up.
         */
        if(hw->autoneg) {
            /* Perform some bounds checking on the hw->autoneg_advertised
             * parameter.  If this variable is zero, then set it to the default.
             */
            hw->autoneg_advertised &= AUTONEG_ADVERTISE_SPEED_DEFAULT;

            /* If autoneg_advertised is zero, we assume it was not defaulted
             * by the calling code so we set to advertise full capability.
             */
            if(hw->autoneg_advertised == 0)
                hw->autoneg_advertised = AUTONEG_ADVERTISE_SPEED_DEFAULT;

            DEBUGOUT("Reconfiguring auto-neg advertisement params\n");
            if((ret_val = em_phy_setup_autoneg(hw))) {
                DEBUGOUT("Error Setting up Auto-Negotiation\n");
                return ret_val;
            }
            DEBUGOUT("Restarting Auto-Neg\n");

            /* Restart auto-negotiation by setting the Auto Neg Enable bit and
             * the Auto Neg Restart bit in the PHY control register.
             */
            if((ret_val = em_read_phy_reg(hw, PHY_CTRL, &phy_data)))
                return ret_val;

            phy_data |= (MII_CR_AUTO_NEG_EN | MII_CR_RESTART_AUTO_NEG);
            if((ret_val = em_write_phy_reg(hw, PHY_CTRL, phy_data)))
                return ret_val;

            /* Does the user want to wait for Auto-Neg to complete here, or
             * check at a later time (for example, callback routine).
             */
            if(hw->wait_autoneg_complete) {
                if((ret_val = em_wait_autoneg(hw))) {
                    DEBUGOUT("Error while waiting for autoneg to complete\n");
                    return ret_val;
                }
            }
            hw->get_link_status = TRUE;
        } else {
            DEBUGOUT("Forcing speed and duplex\n");
            if((ret_val = em_phy_force_speed_duplex(hw))) {
                DEBUGOUT("Error Forcing Speed and Duplex\n");
                return ret_val;
            }
        }
    } /* !hw->phy_reset_disable */

    /* Check link status. Wait up to 100 microseconds for link to become
     * valid.
     */
    for(i = 0; i < 10; i++) {
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
            return ret_val;
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
            return ret_val;

        if(phy_data & MII_SR_LINK_STATUS) {
            /* We have link, so we need to finish the config process:
             *   1) Set up the MAC to the current PHY speed/duplex
             *      if we are on 82543.  If we
             *      are on newer silicon, we only need to configure
             *      collision distance in the Transmit Control Register.
             *   2) Set up flow control on the MAC to that established with
             *      the link partner.
             */
            if(hw->mac_type >= em_82544) {
                em_config_collision_dist(hw);
            } else {
                if((ret_val = em_config_mac_to_phy(hw))) {
                    DEBUGOUT("Error configuring MAC to PHY settings\n");
                    return ret_val;
                }
            }
            if((ret_val = em_config_fc_after_link_up(hw))) {
                DEBUGOUT("Error Configuring Flow Control\n");
                return ret_val;
            }
            DEBUGOUT("Valid link established!!!\n");

            if(hw->phy_type == em_phy_igp) {
                if((ret_val = em_config_dsp_after_link_change(hw, TRUE))) {
                    DEBUGOUT("Error Configuring DSP after link up\n");
                    return ret_val;
                }
            }
            DEBUGOUT("Valid link established!!!\n");
            return E1000_SUCCESS;
        }
        usec_delay(10);
    }

    DEBUGOUT("Unable to establish link!!!\n");
    return E1000_SUCCESS;
}

/******************************************************************************
* Configures PHY autoneg and flow control advertisement settings
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
int32_t
em_phy_setup_autoneg(struct em_hw *hw)
{
    int32_t ret_val;
    uint16_t mii_autoneg_adv_reg;
    uint16_t mii_1000t_ctrl_reg;

    DEBUGFUNC("em_phy_setup_autoneg");

    /* Read the MII Auto-Neg Advertisement Register (Address 4). */
    if((ret_val = em_read_phy_reg(hw, PHY_AUTONEG_ADV,
                                     &mii_autoneg_adv_reg)))
        return ret_val;

    /* Read the MII 1000Base-T Control Register (Address 9). */
    if((ret_val = em_read_phy_reg(hw, PHY_1000T_CTRL, &mii_1000t_ctrl_reg)))
        return ret_val;

    /* Need to parse both autoneg_advertised and fc and set up
     * the appropriate PHY registers.  First we will parse for
     * autoneg_advertised software override.  Since we can advertise
     * a plethora of combinations, we need to check each bit
     * individually.
     */

    /* First we clear all the 10/100 mb speed bits in the Auto-Neg
     * Advertisement Register (Address 4) and the 1000 mb speed bits in
     * the  1000Base-T Control Register (Address 9).
     */
    mii_autoneg_adv_reg &= ~REG4_SPEED_MASK;
    mii_1000t_ctrl_reg &= ~REG9_SPEED_MASK;

    DEBUGOUT1("autoneg_advertised %x\n", hw->autoneg_advertised);

    /* Do we want to advertise 10 Mb Half Duplex? */
    if(hw->autoneg_advertised & ADVERTISE_10_HALF) {
        DEBUGOUT("Advertise 10mb Half duplex\n");
        mii_autoneg_adv_reg |= NWAY_AR_10T_HD_CAPS;
    }

    /* Do we want to advertise 10 Mb Full Duplex? */
    if(hw->autoneg_advertised & ADVERTISE_10_FULL) {
        DEBUGOUT("Advertise 10mb Full duplex\n");
        mii_autoneg_adv_reg |= NWAY_AR_10T_FD_CAPS;
    }

    /* Do we want to advertise 100 Mb Half Duplex? */
    if(hw->autoneg_advertised & ADVERTISE_100_HALF) {
        DEBUGOUT("Advertise 100mb Half duplex\n");
        mii_autoneg_adv_reg |= NWAY_AR_100TX_HD_CAPS;
    }

    /* Do we want to advertise 100 Mb Full Duplex? */
    if(hw->autoneg_advertised & ADVERTISE_100_FULL) {
        DEBUGOUT("Advertise 100mb Full duplex\n");
        mii_autoneg_adv_reg |= NWAY_AR_100TX_FD_CAPS;
    }

    /* We do not allow the Phy to advertise 1000 Mb Half Duplex */
    if(hw->autoneg_advertised & ADVERTISE_1000_HALF) {
        DEBUGOUT("Advertise 1000mb Half duplex requested, request denied!\n");
    }

    /* Do we want to advertise 1000 Mb Full Duplex? */
    if(hw->autoneg_advertised & ADVERTISE_1000_FULL) {
        DEBUGOUT("Advertise 1000mb Full duplex\n");
        mii_1000t_ctrl_reg |= CR_1000T_FD_CAPS;
    }

    /* Check for a software override of the flow control settings, and
     * setup the PHY advertisement registers accordingly.  If
     * auto-negotiation is enabled, then software will have to set the
     * "PAUSE" bits to the correct value in the Auto-Negotiation
     * Advertisement Register (PHY_AUTONEG_ADV) and re-start auto-negotiation.
     *
     * The possible values of the "fc" parameter are:
     *      0:  Flow control is completely disabled
     *      1:  Rx flow control is enabled (we can receive pause frames
     *          but not send pause frames).
     *      2:  Tx flow control is enabled (we can send pause frames
     *          but we do not support receiving pause frames).
     *      3:  Both Rx and TX flow control (symmetric) are enabled.
     *  other:  No software override.  The flow control configuration
     *          in the EEPROM is used.
     */
    switch (hw->fc) {
    case em_fc_none: /* 0 */
        /* Flow control (RX & TX) is completely disabled by a
         * software over-ride.
         */
        mii_autoneg_adv_reg &= ~(NWAY_AR_ASM_DIR | NWAY_AR_PAUSE);
        break;
    case em_fc_rx_pause: /* 1 */
        /* RX Flow control is enabled, and TX Flow control is
         * disabled, by a software over-ride.
         */
        /* Since there really isn't a way to advertise that we are
         * capable of RX Pause ONLY, we will advertise that we
         * support both symmetric and asymmetric RX PAUSE.  Later
         * (in em_config_fc_after_link_up) we will disable the
         *hw's ability to send PAUSE frames.
         */
        mii_autoneg_adv_reg |= (NWAY_AR_ASM_DIR | NWAY_AR_PAUSE);
        break;
    case em_fc_tx_pause: /* 2 */
        /* TX Flow control is enabled, and RX Flow control is
         * disabled, by a software over-ride.
         */
        mii_autoneg_adv_reg |= NWAY_AR_ASM_DIR;
        mii_autoneg_adv_reg &= ~NWAY_AR_PAUSE;
        break;
    case em_fc_full: /* 3 */
        /* Flow control (both RX and TX) is enabled by a software
         * over-ride.
         */
        mii_autoneg_adv_reg |= (NWAY_AR_ASM_DIR | NWAY_AR_PAUSE);
        break;
    default:
        DEBUGOUT("Flow control param set incorrectly\n");
        return -E1000_ERR_CONFIG;
    }

    if((ret_val = em_write_phy_reg(hw, PHY_AUTONEG_ADV,
                                      mii_autoneg_adv_reg)))
        return ret_val;

    DEBUGOUT1("Auto-Neg Advertising %x\n", mii_autoneg_adv_reg);

    if((ret_val = em_write_phy_reg(hw, PHY_1000T_CTRL, mii_1000t_ctrl_reg)))
        return ret_val;

    return E1000_SUCCESS;
}

/******************************************************************************
* Force PHY speed and duplex settings to hw->forced_speed_duplex
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
static int32_t
em_phy_force_speed_duplex(struct em_hw *hw)
{
    uint32_t ctrl;
    int32_t ret_val;
    uint16_t mii_ctrl_reg;
    uint16_t mii_status_reg;
    uint16_t phy_data;
    uint16_t i;

    DEBUGFUNC("em_phy_force_speed_duplex");

    /* Turn off Flow control if we are forcing speed and duplex. */
    hw->fc = em_fc_none;

    DEBUGOUT1("hw->fc = %d\n", hw->fc);

    /* Read the Device Control Register. */
    ctrl = E1000_READ_REG(hw, CTRL);

    /* Set the bits to Force Speed and Duplex in the Device Ctrl Reg. */
    ctrl |= (E1000_CTRL_FRCSPD | E1000_CTRL_FRCDPX);
    ctrl &= ~(DEVICE_SPEED_MASK);

    /* Clear the Auto Speed Detect Enable bit. */
    ctrl &= ~E1000_CTRL_ASDE;

    /* Read the MII Control Register. */
    if((ret_val = em_read_phy_reg(hw, PHY_CTRL, &mii_ctrl_reg)))
        return ret_val;

    /* We need to disable autoneg in order to force link and duplex. */

    mii_ctrl_reg &= ~MII_CR_AUTO_NEG_EN;

    /* Are we forcing Full or Half Duplex? */
    if(hw->forced_speed_duplex == em_100_full ||
       hw->forced_speed_duplex == em_10_full) {
        /* We want to force full duplex so we SET the full duplex bits in the
         * Device and MII Control Registers.
         */
        ctrl |= E1000_CTRL_FD;
        mii_ctrl_reg |= MII_CR_FULL_DUPLEX;
        DEBUGOUT("Full Duplex\n");
    } else {
        /* We want to force half duplex so we CLEAR the full duplex bits in
         * the Device and MII Control Registers.
         */
        ctrl &= ~E1000_CTRL_FD;
        mii_ctrl_reg &= ~MII_CR_FULL_DUPLEX;
        DEBUGOUT("Half Duplex\n");
    }

    /* Are we forcing 100Mbps??? */
    if(hw->forced_speed_duplex == em_100_full ||
       hw->forced_speed_duplex == em_100_half) {
        /* Set the 100Mb bit and turn off the 1000Mb and 10Mb bits. */
        ctrl |= E1000_CTRL_SPD_100;
        mii_ctrl_reg |= MII_CR_SPEED_100;
        mii_ctrl_reg &= ~(MII_CR_SPEED_1000 | MII_CR_SPEED_10);
        DEBUGOUT("Forcing 100mb ");
    } else {
        /* Set the 10Mb bit and turn off the 1000Mb and 100Mb bits. */
        ctrl &= ~(E1000_CTRL_SPD_1000 | E1000_CTRL_SPD_100);
        mii_ctrl_reg |= MII_CR_SPEED_10;
        mii_ctrl_reg &= ~(MII_CR_SPEED_1000 | MII_CR_SPEED_100);
        DEBUGOUT("Forcing 10mb ");
    }

    em_config_collision_dist(hw);

    /* Write the configured values back to the Device Control Reg. */
    E1000_WRITE_REG(hw, CTRL, ctrl);

    if (hw->phy_type == em_phy_m88) {
        if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_CTRL,
                                         &phy_data)))
            return ret_val;

        /* Clear Auto-Crossover to force MDI manually. M88E1000 requires MDI
         * forced whenever speed are duplex are forced.
         */
        phy_data &= ~M88E1000_PSCR_AUTO_X_MODE;
        if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_SPEC_CTRL,
                                          phy_data)))
            return ret_val;

        DEBUGOUT1("M88E1000 PSCR: %x \n", phy_data);

        /* Need to reset the PHY or these changes will be ignored */
        mii_ctrl_reg |= MII_CR_RESET;
    } else {
        /* Clear Auto-Crossover to force MDI manually.  IGP requires MDI
         * forced whenever speed or duplex are forced.
         */
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_CTRL,
                                         &phy_data)))
            return ret_val;

        phy_data &= ~IGP01E1000_PSCR_AUTO_MDIX;
        phy_data &= ~IGP01E1000_PSCR_FORCE_MDI_MDIX;

        if((ret_val = em_write_phy_reg(hw, IGP01E1000_PHY_PORT_CTRL,
                                          phy_data)))
            return ret_val;
    }

    /* Write back the modified PHY MII control register. */
    if((ret_val = em_write_phy_reg(hw, PHY_CTRL, mii_ctrl_reg)))
        return ret_val;

    usec_delay(1);

    /* The wait_autoneg_complete flag may be a little misleading here.
     * Since we are forcing speed and duplex, Auto-Neg is not enabled.
     * But we do want to delay for a period while forcing only so we
     * don't generate false No Link messages.  So we will wait here
     * only if the user has set wait_autoneg_complete to 1, which is
     * the default.
     */
    if(hw->wait_autoneg_complete) {
        /* We will wait for autoneg to complete. */
        DEBUGOUT("Waiting for forced speed/duplex link.\n");
        mii_status_reg = 0;

        /* We will wait for autoneg to complete or 4.5 seconds to expire. */
        for(i = PHY_FORCE_TIME; i > 0; i--) {
            /* Read the MII Status Register and wait for Auto-Neg Complete bit
             * to be set.
             */
            if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &mii_status_reg)))
                return ret_val;

            if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &mii_status_reg)))
                return ret_val;

            if(mii_status_reg & MII_SR_LINK_STATUS) break;
            msec_delay(100);
        }
        if(i == 0) { /* We didn't get link */
            /* Reset the DSP and wait again for link. */
            if((ret_val = em_phy_reset_dsp(hw))) {
                DEBUGOUT("Error Resetting PHY DSP\n");
                return ret_val;
            }
        }
        /* This loop will early-out if the link condition has been met.  */
        for(i = PHY_FORCE_TIME; i > 0; i--) {
            if(mii_status_reg & MII_SR_LINK_STATUS) break;
            msec_delay(100);
            /* Read the MII Status Register and wait for Auto-Neg Complete bit
             * to be set.
             */
            if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &mii_status_reg)))
                return ret_val;

            if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &mii_status_reg)))
                return ret_val;
        }
    }

    if (hw->phy_type == em_phy_m88) {
        /* Because we reset the PHY above, we need to re-force TX_CLK in the
         * Extended PHY Specific Control Register to 25MHz clock.  This value
         * defaults back to a 2.5MHz clock when the PHY is reset.
         */
        if((ret_val = em_read_phy_reg(hw, M88E1000_EXT_PHY_SPEC_CTRL,
                                         &phy_data)))
            return ret_val;

        phy_data |= M88E1000_EPSCR_TX_CLK_25;
        if((ret_val = em_write_phy_reg(hw, M88E1000_EXT_PHY_SPEC_CTRL,
                                          phy_data)))
            return ret_val;

        /* In addition, because of the s/w reset above, we need to enable CRS on
         * TX.  This must be set for both full and half duplex operation.
         */
        if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_CTRL,
                                         &phy_data)))
            return ret_val;

        phy_data |= M88E1000_PSCR_ASSERT_CRS_ON_TX;
        if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_SPEC_CTRL,
                                          phy_data)))
            return ret_val;

    }
    return E1000_SUCCESS;
}

/******************************************************************************
* Sets the collision distance in the Transmit Control register
*
* hw - Struct containing variables accessed by shared code
*
* Link should have been established previously. Reads the speed and duplex
* information from the Device Status register.
******************************************************************************/
void
em_config_collision_dist(struct em_hw *hw)
{
    uint32_t tctl;

    DEBUGFUNC("em_config_collision_dist");

    tctl = E1000_READ_REG(hw, TCTL);

    tctl &= ~E1000_TCTL_COLD;
    tctl |= E1000_COLLISION_DISTANCE << E1000_COLD_SHIFT;

    E1000_WRITE_REG(hw, TCTL, tctl);
    E1000_WRITE_FLUSH(hw);
}

/******************************************************************************
* Sets MAC speed and duplex settings to reflect the those in the PHY
*
* hw - Struct containing variables accessed by shared code
* mii_reg - data to write to the MII control register
*
* The contents of the PHY register containing the needed information need to
* be passed in.
******************************************************************************/
static int32_t
em_config_mac_to_phy(struct em_hw *hw)
{
    uint32_t ctrl;
    int32_t ret_val;
    uint16_t phy_data;

    DEBUGFUNC("em_config_mac_to_phy");

    /* Read the Device Control Register and set the bits to Force Speed
     * and Duplex.
     */
    ctrl = E1000_READ_REG(hw, CTRL);
    ctrl |= (E1000_CTRL_FRCSPD | E1000_CTRL_FRCDPX);
    ctrl &= ~(E1000_CTRL_SPD_SEL | E1000_CTRL_ILOS);

    /* Set up duplex in the Device Control and Transmit Control
     * registers depending on negotiated values.
     */
    if (hw->phy_type == em_phy_igp) {
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_STATUS,
                                         &phy_data)))
            return ret_val;

        if(phy_data & IGP01E1000_PSSR_FULL_DUPLEX) ctrl |= E1000_CTRL_FD;
        else ctrl &= ~E1000_CTRL_FD;

        em_config_collision_dist(hw);

        /* Set up speed in the Device Control register depending on
         * negotiated values.
         */
        if((phy_data & IGP01E1000_PSSR_SPEED_MASK) ==
           IGP01E1000_PSSR_SPEED_1000MBPS)
            ctrl |= E1000_CTRL_SPD_1000;
        else if((phy_data & IGP01E1000_PSSR_SPEED_MASK) ==
                IGP01E1000_PSSR_SPEED_100MBPS)
            ctrl |= E1000_CTRL_SPD_100;
    } else {
        if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_STATUS,
                                         &phy_data)))
            return ret_val;

        if(phy_data & M88E1000_PSSR_DPLX) ctrl |= E1000_CTRL_FD;
        else ctrl &= ~E1000_CTRL_FD;

        em_config_collision_dist(hw);

        /* Set up speed in the Device Control register depending on
         * negotiated values.
         */
        if((phy_data & M88E1000_PSSR_SPEED) == M88E1000_PSSR_1000MBS)
            ctrl |= E1000_CTRL_SPD_1000;
        else if((phy_data & M88E1000_PSSR_SPEED) == M88E1000_PSSR_100MBS)
            ctrl |= E1000_CTRL_SPD_100;
    }
    /* Write the configured values back to the Device Control Reg. */
    E1000_WRITE_REG(hw, CTRL, ctrl);
    return E1000_SUCCESS;
}

/******************************************************************************
 * Forces the MAC's flow control settings.
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Sets the TFCE and RFCE bits in the device control register to reflect
 * the adapter settings. TFCE and RFCE need to be explicitly set by
 * software when a Copper PHY is used because autonegotiation is managed
 * by the PHY rather than the MAC. Software must also configure these
 * bits when link is forced on a fiber connection.
 *****************************************************************************/
int32_t
em_force_mac_fc(struct em_hw *hw)
{
    uint32_t ctrl;

    DEBUGFUNC("em_force_mac_fc");

    /* Get the current configuration of the Device Control Register */
    ctrl = E1000_READ_REG(hw, CTRL);

    /* Because we didn't get link via the internal auto-negotiation
     * mechanism (we either forced link or we got link via PHY
     * auto-neg), we have to manually enable/disable transmit an
     * receive flow control.
     *
     * The "Case" statement below enables/disable flow control
     * according to the "hw->fc" parameter.
     *
     * The possible values of the "fc" parameter are:
     *      0:  Flow control is completely disabled
     *      1:  Rx flow control is enabled (we can receive pause
     *          frames but not send pause frames).
     *      2:  Tx flow control is enabled (we can send pause frames
     *          frames but we do not receive pause frames).
     *      3:  Both Rx and TX flow control (symmetric) is enabled.
     *  other:  No other values should be possible at this point.
     */

    switch (hw->fc) {
    case em_fc_none:
        ctrl &= (~(E1000_CTRL_TFCE | E1000_CTRL_RFCE));
        break;
    case em_fc_rx_pause:
        ctrl &= (~E1000_CTRL_TFCE);
        ctrl |= E1000_CTRL_RFCE;
        break;
    case em_fc_tx_pause:
        ctrl &= (~E1000_CTRL_RFCE);
        ctrl |= E1000_CTRL_TFCE;
        break;
    case em_fc_full:
        ctrl |= (E1000_CTRL_TFCE | E1000_CTRL_RFCE);
        break;
    default:
        DEBUGOUT("Flow control param set incorrectly\n");
        return -E1000_ERR_CONFIG;
    }

    /* Disable TX Flow Control for 82542 (rev 2.0) */
    if(hw->mac_type == em_82542_rev2_0)
        ctrl &= (~E1000_CTRL_TFCE);

    E1000_WRITE_REG(hw, CTRL, ctrl);
    return E1000_SUCCESS;
}

/******************************************************************************
 * Configures flow control settings after link is established
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Should be called immediately after a valid link has been established.
 * Forces MAC flow control settings if link was forced. When in MII/GMII mode
 * and autonegotiation is enabled, the MAC flow control settings will be set
 * based on the flow control negotiated by the PHY. In TBI mode, the TFCE
 * and RFCE bits will be automaticaly set to the negotiated flow control mode.
 *****************************************************************************/
int32_t
em_config_fc_after_link_up(struct em_hw *hw)
{
    int32_t ret_val;
    uint16_t mii_status_reg;
    uint16_t mii_nway_adv_reg;
    uint16_t mii_nway_lp_ability_reg;
    uint16_t speed;
    uint16_t duplex;

    DEBUGFUNC("em_config_fc_after_link_up");

    /* Check for the case where we have fiber media and auto-neg failed
     * so we had to force link.  In this case, we need to force the
     * configuration of the MAC to match the "fc" parameter.
     */
    if(((hw->media_type == em_media_type_fiber) && (hw->autoneg_failed)) ||
       ((hw->media_type == em_media_type_internal_serdes) && (hw->autoneg_failed)) ||
       ((hw->media_type == em_media_type_copper) && (!hw->autoneg))) {
        if((ret_val = em_force_mac_fc(hw))) {
            DEBUGOUT("Error forcing flow control settings\n");
            return ret_val;
        }
    }

    /* Check for the case where we have copper media and auto-neg is
     * enabled.  In this case, we need to check and see if Auto-Neg
     * has completed, and if so, how the PHY and link partner has
     * flow control configured.
     */
    if((hw->media_type == em_media_type_copper) && hw->autoneg) {
        /* Read the MII Status Register and check to see if AutoNeg
         * has completed.  We read this twice because this reg has
         * some "sticky" (latched) bits.
         */
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &mii_status_reg)))
            return ret_val;
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &mii_status_reg)))
            return ret_val;

        if(mii_status_reg & MII_SR_AUTONEG_COMPLETE) {
            /* The AutoNeg process has completed, so we now need to
             * read both the Auto Negotiation Advertisement Register
             * (Address 4) and the Auto_Negotiation Base Page Ability
             * Register (Address 5) to determine how flow control was
             * negotiated.
             */
            if((ret_val = em_read_phy_reg(hw, PHY_AUTONEG_ADV,
                                             &mii_nway_adv_reg)))
                return ret_val;
            if((ret_val = em_read_phy_reg(hw, PHY_LP_ABILITY,
                                             &mii_nway_lp_ability_reg)))
                return ret_val;

            /* Two bits in the Auto Negotiation Advertisement Register
             * (Address 4) and two bits in the Auto Negotiation Base
             * Page Ability Register (Address 5) determine flow control
             * for both the PHY and the link partner.  The following
             * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
             * 1999, describes these PAUSE resolution bits and how flow
             * control is determined based upon these settings.
             * NOTE:  DC = Don't Care
             *
             *   LOCAL DEVICE  |   LINK PARTNER
             * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
             *-------|---------|-------|---------|--------------------
             *   0   |    0    |  DC   |   DC    | em_fc_none
             *   0   |    1    |   0   |   DC    | em_fc_none
             *   0   |    1    |   1   |    0    | em_fc_none
             *   0   |    1    |   1   |    1    | em_fc_tx_pause
             *   1   |    0    |   0   |   DC    | em_fc_none
             *   1   |   DC    |   1   |   DC    | em_fc_full
             *   1   |    1    |   0   |    0    | em_fc_none
             *   1   |    1    |   0   |    1    | em_fc_rx_pause
             *
             */
            /* Are both PAUSE bits set to 1?  If so, this implies
             * Symmetric Flow Control is enabled at both ends.  The
             * ASM_DIR bits are irrelevant per the spec.
             *
             * For Symmetric Flow Control:
             *
             *   LOCAL DEVICE  |   LINK PARTNER
             * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
             *-------|---------|-------|---------|--------------------
             *   1   |   DC    |   1   |   DC    | em_fc_full
             *
             */
            if((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
               (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE)) {
                /* Now we need to check if the user selected RX ONLY
                 * of pause frames.  In this case, we had to advertise
                 * FULL flow control because we could not advertise RX
                 * ONLY. Hence, we must now check to see if we need to
                 * turn OFF  the TRANSMISSION of PAUSE frames.
                 */
                if(hw->original_fc == em_fc_full) {
                    hw->fc = em_fc_full;
                    DEBUGOUT("Flow Control = FULL.\r\n");
                } else {
                    hw->fc = em_fc_rx_pause;
                    DEBUGOUT("Flow Control = RX PAUSE frames only.\r\n");
                }
            }
            /* For receiving PAUSE frames ONLY.
             *
             *   LOCAL DEVICE  |   LINK PARTNER
             * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
             *-------|---------|-------|---------|--------------------
             *   0   |    1    |   1   |    1    | em_fc_tx_pause
             *
             */
            else if(!(mii_nway_adv_reg & NWAY_AR_PAUSE) &&
                    (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
                    (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
                    (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
                hw->fc = em_fc_tx_pause;
                DEBUGOUT("Flow Control = TX PAUSE frames only.\r\n");
            }
            /* For transmitting PAUSE frames ONLY.
             *
             *   LOCAL DEVICE  |   LINK PARTNER
             * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
             *-------|---------|-------|---------|--------------------
             *   1   |    1    |   0   |    1    | em_fc_rx_pause
             *
             */
            else if((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
                    (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
                    !(mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
                    (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
                hw->fc = em_fc_rx_pause;
                DEBUGOUT("Flow Control = RX PAUSE frames only.\r\n");
            }
            /* Per the IEEE spec, at this point flow control should be
             * disabled.  However, we want to consider that we could
             * be connected to a legacy switch that doesn't advertise
             * desired flow control, but can be forced on the link
             * partner.  So if we advertised no flow control, that is
             * what we will resolve to.  If we advertised some kind of
             * receive capability (Rx Pause Only or Full Flow Control)
             * and the link partner advertised none, we will configure
             * ourselves to enable Rx Flow Control only.  We can do
             * this safely for two reasons:  If the link partner really
             * didn't want flow control enabled, and we enable Rx, no
             * harm done since we won't be receiving any PAUSE frames
             * anyway.  If the intent on the link partner was to have
             * flow control enabled, then by us enabling RX only, we
             * can at least receive pause frames and process them.
             * This is a good idea because in most cases, since we are
             * predominantly a server NIC, more times than not we will
             * be asked to delay transmission of packets than asking
             * our link partner to pause transmission of frames.
             */
            else if((hw->original_fc == em_fc_none ||
                     hw->original_fc == em_fc_tx_pause) ||
                    hw->fc_strict_ieee) {
                hw->fc = em_fc_none;
                DEBUGOUT("Flow Control = NONE.\r\n");
            } else {
                hw->fc = em_fc_rx_pause;
                DEBUGOUT("Flow Control = RX PAUSE frames only.\r\n");
            }

            /* Now we need to do one last check...  If we auto-
             * negotiated to HALF DUPLEX, flow control should not be
             * enabled per IEEE 802.3 spec.
             */
            if((ret_val = em_get_speed_and_duplex(hw, &speed, &duplex))) {
                DEBUGOUT("Error getting link speed and duplex\n");
                return ret_val;
            }

            if(duplex == HALF_DUPLEX)
                hw->fc = em_fc_none;

            /* Now we call a subroutine to actually force the MAC
             * controller to use the correct flow control settings.
             */
            if((ret_val = em_force_mac_fc(hw))) {
                DEBUGOUT("Error forcing flow control settings\n");
                return ret_val;
            }
        } else {
            DEBUGOUT("Copper PHY and Auto Neg has not completed.\r\n");
        }
    }
    return E1000_SUCCESS;
}

/******************************************************************************
 * Checks to see if the link status of the hardware has changed.
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Called by any function that needs to check the link status of the adapter.
 *****************************************************************************/
int32_t
em_check_for_link(struct em_hw *hw)
{
    uint32_t rxcw;
    uint32_t ctrl;
    uint32_t status;
    uint32_t rctl;
    uint32_t signal = 0;
    int32_t ret_val;
    uint16_t phy_data;
    uint16_t lp_capability;

    DEBUGFUNC("em_check_for_link");

    /* On adapters with a MAC newer than 82544, SW Defineable pin 1 will be
     * set when the optics detect a signal. On older adapters, it will be
     * cleared when there is a signal.  This applies to fiber media only.
     */
    if(hw->media_type == em_media_type_fiber)
        signal = (hw->mac_type > em_82544) ? E1000_CTRL_SWDPIN1 : 0;

    ctrl = E1000_READ_REG(hw, CTRL);
    status = E1000_READ_REG(hw, STATUS);
    rxcw = E1000_READ_REG(hw, RXCW);

    /* If we have a copper PHY then we only want to go out to the PHY
     * registers to see if Auto-Neg has completed and/or if our link
     * status has changed.  The get_link_status flag will be set if we
     * receive a Link Status Change interrupt or we have Rx Sequence
     * Errors.
     */
    if((hw->media_type == em_media_type_copper) && hw->get_link_status) {
        /* First we want to see if the MII Status Register reports
         * link.  If so, then we want to get the current speed/duplex
         * of the PHY.
         * Read the register twice since the link bit is sticky.
         */
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
            return ret_val;
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
            return ret_val;

        if(phy_data & MII_SR_LINK_STATUS) {
            hw->get_link_status = FALSE;
            /* Check if there was DownShift, must be checked immediately after
             * link-up */
            em_check_downshift(hw);

        } else {
            /* No link detected */
            em_config_dsp_after_link_change(hw, FALSE);
            return 0;
        }

        /* If we are forcing speed/duplex, then we simply return since
         * we have already determined whether we have link or not.
         */
        if(!hw->autoneg) return -E1000_ERR_CONFIG;

        /* optimize the dsp settings for the igp phy */
        em_config_dsp_after_link_change(hw, TRUE);

        /* We have a M88E1000 PHY and Auto-Neg is enabled.  If we
         * have Si on board that is 82544 or newer, Auto
         * Speed Detection takes care of MAC speed/duplex
         * configuration.  So we only need to configure Collision
         * Distance in the MAC.  Otherwise, we need to force
         * speed/duplex on the MAC to the current PHY speed/duplex
         * settings.
         */
        if(hw->mac_type >= em_82544)
            em_config_collision_dist(hw);
        else {
            if((ret_val = em_config_mac_to_phy(hw))) {
                DEBUGOUT("Error configuring MAC to PHY settings\n");
                return ret_val;
            }
        }

        /* Configure Flow Control now that Auto-Neg has completed. First, we
         * need to restore the desired flow control settings because we may
         * have had to re-autoneg with a different link partner.
         */
        if((ret_val = em_config_fc_after_link_up(hw))) {
            DEBUGOUT("Error configuring flow control\n");
            return ret_val;
        }

        /* At this point we know that we are on copper and we have
         * auto-negotiated link.  These are conditions for checking the link
         * parter capability register.  We use the link partner capability to
         * determine if TBI Compatibility needs to be turned on or off.  If
         * the link partner advertises any speed in addition to Gigabit, then
         * we assume that they are GMII-based, and TBI compatibility is not
         * needed. If no other speeds are advertised, we assume the link
         * partner is TBI-based, and we turn on TBI Compatibility.
         */
        if(hw->tbi_compatibility_en) {
            if((ret_val = em_read_phy_reg(hw, PHY_LP_ABILITY,
                                             &lp_capability)))
                return ret_val;
            if(lp_capability & (NWAY_LPAR_10T_HD_CAPS |
                                NWAY_LPAR_10T_FD_CAPS |
                                NWAY_LPAR_100TX_HD_CAPS |
                                NWAY_LPAR_100TX_FD_CAPS |
                                NWAY_LPAR_100T4_CAPS)) {
                /* If our link partner advertises anything in addition to
                 * gigabit, we do not need to enable TBI compatibility.
                 */
                if(hw->tbi_compatibility_on) {
                    /* If we previously were in the mode, turn it off. */
                    rctl = E1000_READ_REG(hw, RCTL);
                    rctl &= ~E1000_RCTL_SBP;
                    E1000_WRITE_REG(hw, RCTL, rctl);
                    hw->tbi_compatibility_on = FALSE;
                }
            } else {
                /* If TBI compatibility is was previously off, turn it on. For
                 * compatibility with a TBI link partner, we will store bad
                 * packets. Some frames have an additional byte on the end and
                 * will look like CRC errors to to the hardware.
                 */
                if(!hw->tbi_compatibility_on) {
                    hw->tbi_compatibility_on = TRUE;
                    rctl = E1000_READ_REG(hw, RCTL);
                    rctl |= E1000_RCTL_SBP;
                    E1000_WRITE_REG(hw, RCTL, rctl);
                }
            }
        }
    }
    /* If we don't have link (auto-negotiation failed or link partner cannot
     * auto-negotiate), the cable is plugged in (we have signal), and our
     * link partner is not trying to auto-negotiate with us (we are receiving
     * idles or data), we need to force link up. We also need to give
     * auto-negotiation time to complete, in case the cable was just plugged
     * in. The autoneg_failed flag does this.
     */
    else if((((hw->media_type == em_media_type_fiber) &&
            ((ctrl & E1000_CTRL_SWDPIN1) == signal)) ||
            (hw->media_type == em_media_type_internal_serdes)) &&
            (!(status & E1000_STATUS_LU)) &&
            (!(rxcw & E1000_RXCW_C))) {
        if(hw->autoneg_failed == 0) {
            hw->autoneg_failed = 1;
            return 0;
        }
        DEBUGOUT("NOT RXing /C/, disable AutoNeg and force link.\r\n");

        /* Disable auto-negotiation in the TXCW register */
        E1000_WRITE_REG(hw, TXCW, (hw->txcw & ~E1000_TXCW_ANE));

        /* Force link-up and also force full-duplex. */
        ctrl = E1000_READ_REG(hw, CTRL);
        ctrl |= (E1000_CTRL_SLU | E1000_CTRL_FD);
        E1000_WRITE_REG(hw, CTRL, ctrl);

        /* Configure Flow Control after forcing link up. */
        if((ret_val = em_config_fc_after_link_up(hw))) {
            DEBUGOUT("Error configuring flow control\n");
            return ret_val;
        }
    }
    /* If we are forcing link and we are receiving /C/ ordered sets, re-enable
     * auto-negotiation in the TXCW register and disable forced link in the
     * Device Control register in an attempt to auto-negotiate with our link
     * partner.
     */
    else if(((hw->media_type == em_media_type_fiber) ||
             (hw->media_type == em_media_type_internal_serdes)) &&
              (ctrl & E1000_CTRL_SLU) &&
              (rxcw & E1000_RXCW_C)) {
        DEBUGOUT("RXing /C/, enable AutoNeg and stop forcing link.\r\n");
        E1000_WRITE_REG(hw, TXCW, hw->txcw);
        E1000_WRITE_REG(hw, CTRL, (ctrl & ~E1000_CTRL_SLU));
    }
    return E1000_SUCCESS;
}

/******************************************************************************
 * Detects the current speed and duplex settings of the hardware.
 *
 * hw - Struct containing variables accessed by shared code
 * speed - Speed of the connection
 * duplex - Duplex setting of the connection
 *****************************************************************************/
int32_t
em_get_speed_and_duplex(struct em_hw *hw,
                           uint16_t *speed,
                           uint16_t *duplex)
{
    uint32_t status;
    int32_t ret_val;
    uint16_t phy_data;

    DEBUGFUNC("em_get_speed_and_duplex");

    if(hw->mac_type >= em_82543) {
        status = E1000_READ_REG(hw, STATUS);
        if(status & E1000_STATUS_SPEED_1000) {
            *speed = SPEED_1000;
            DEBUGOUT("1000 Mbs, ");
        } else if(status & E1000_STATUS_SPEED_100) {
            *speed = SPEED_100;
            DEBUGOUT("100 Mbs, ");
        } else {
            *speed = SPEED_10;
            DEBUGOUT("10 Mbs, ");
        }

        if(status & E1000_STATUS_FD) {
            *duplex = FULL_DUPLEX;
            DEBUGOUT("Full Duplex\r\n");
        } else {
            *duplex = HALF_DUPLEX;
            DEBUGOUT(" Half Duplex\r\n");
        }
    } else {
        DEBUGOUT("1000 Mbs, Full Duplex\r\n");
        *speed = SPEED_1000;
        *duplex = FULL_DUPLEX;
    }

    /* IGP01 PHY may advertise full duplex operation after speed downgrade even
     * if it is operating at half duplex.  Here we set the duplex settings to
     * match the duplex in the link partner's capabilities.
     */
    if(hw->phy_type == em_phy_igp && hw->speed_downgraded) {
        if((ret_val = em_read_phy_reg(hw, PHY_AUTONEG_EXP, &phy_data)))
            return ret_val;

        if(!(phy_data & NWAY_ER_LP_NWAY_CAPS))
            *duplex = HALF_DUPLEX;
        else {
            if((ret_val == em_read_phy_reg(hw, PHY_LP_ABILITY, &phy_data)))
                return ret_val;
            if((*speed == SPEED_100 && !(phy_data & NWAY_LPAR_100TX_FD_CAPS)) ||
               (*speed == SPEED_10 && !(phy_data & NWAY_LPAR_10T_FD_CAPS)))
                *duplex = HALF_DUPLEX;
        }
    }

    return E1000_SUCCESS;
}

/******************************************************************************
* Blocks until autoneg completes or times out (~4.5 seconds)
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
int32_t
em_wait_autoneg(struct em_hw *hw)
{
    int32_t ret_val;
    uint16_t i;
    uint16_t phy_data;

    DEBUGFUNC("em_wait_autoneg");
    DEBUGOUT("Waiting for Auto-Neg to complete.\n");

    /* We will wait for autoneg to complete or 4.5 seconds to expire. */
    for(i = PHY_AUTO_NEG_TIME; i > 0; i--) {
        /* Read the MII Status Register and wait for Auto-Neg
         * Complete bit to be set.
         */
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
            return ret_val;
        if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
            return ret_val;
        if(phy_data & MII_SR_AUTONEG_COMPLETE) {
            return E1000_SUCCESS;
        }
        msec_delay(100);
    }
    return E1000_SUCCESS;
}

/******************************************************************************
* Raises the Management Data Clock
*
* hw - Struct containing variables accessed by shared code
* ctrl - Device control register's current value
******************************************************************************/
static void
em_raise_mdi_clk(struct em_hw *hw,
                    uint32_t *ctrl)
{
    /* Raise the clock input to the Management Data Clock (by setting the MDC
     * bit), and then delay 10 microseconds.
     */
    E1000_WRITE_REG(hw, CTRL, (*ctrl | E1000_CTRL_MDC));
    E1000_WRITE_FLUSH(hw);
    usec_delay(10);
}

/******************************************************************************
* Lowers the Management Data Clock
*
* hw - Struct containing variables accessed by shared code
* ctrl - Device control register's current value
******************************************************************************/
static void
em_lower_mdi_clk(struct em_hw *hw,
                    uint32_t *ctrl)
{
    /* Lower the clock input to the Management Data Clock (by clearing the MDC
     * bit), and then delay 10 microseconds.
     */
    E1000_WRITE_REG(hw, CTRL, (*ctrl & ~E1000_CTRL_MDC));
    E1000_WRITE_FLUSH(hw);
    usec_delay(10);
}

/******************************************************************************
* Shifts data bits out to the PHY
*
* hw - Struct containing variables accessed by shared code
* data - Data to send out to the PHY
* count - Number of bits to shift out
*
* Bits are shifted out in MSB to LSB order.
******************************************************************************/
static void
em_shift_out_mdi_bits(struct em_hw *hw,
                         uint32_t data,
                         uint16_t count)
{
    uint32_t ctrl;
    uint32_t mask;

    /* We need to shift "count" number of bits out to the PHY. So, the value
     * in the "data" parameter will be shifted out to the PHY one bit at a
     * time. In order to do this, "data" must be broken down into bits.
     */
    mask = 0x01;
    mask <<= (count - 1);

    ctrl = E1000_READ_REG(hw, CTRL);

    /* Set MDIO_DIR and MDC_DIR direction bits to be used as output pins. */
    ctrl |= (E1000_CTRL_MDIO_DIR | E1000_CTRL_MDC_DIR);

    while(mask) {
        /* A "1" is shifted out to the PHY by setting the MDIO bit to "1" and
         * then raising and lowering the Management Data Clock. A "0" is
         * shifted out to the PHY by setting the MDIO bit to "0" and then
         * raising and lowering the clock.
         */
        if(data & mask) ctrl |= E1000_CTRL_MDIO;
        else ctrl &= ~E1000_CTRL_MDIO;

        E1000_WRITE_REG(hw, CTRL, ctrl);
        E1000_WRITE_FLUSH(hw);

        usec_delay(10);

        em_raise_mdi_clk(hw, &ctrl);
        em_lower_mdi_clk(hw, &ctrl);

        mask = mask >> 1;
    }
}

/******************************************************************************
* Shifts data bits in from the PHY
*
* hw - Struct containing variables accessed by shared code
*
* Bits are shifted in in MSB to LSB order.
******************************************************************************/
static uint16_t
em_shift_in_mdi_bits(struct em_hw *hw)
{
    uint32_t ctrl;
    uint16_t data = 0;
    uint8_t i;

    /* In order to read a register from the PHY, we need to shift in a total
     * of 18 bits from the PHY. The first two bit (turnaround) times are used
     * to avoid contention on the MDIO pin when a read operation is performed.
     * These two bits are ignored by us and thrown away. Bits are "shifted in"
     * by raising the input to the Management Data Clock (setting the MDC bit),
     * and then reading the value of the MDIO bit.
     */
    ctrl = E1000_READ_REG(hw, CTRL);

    /* Clear MDIO_DIR (SWDPIO1) to indicate this bit is to be used as input. */
    ctrl &= ~E1000_CTRL_MDIO_DIR;
    ctrl &= ~E1000_CTRL_MDIO;

    E1000_WRITE_REG(hw, CTRL, ctrl);
    E1000_WRITE_FLUSH(hw);

    /* Raise and Lower the clock before reading in the data. This accounts for
     * the turnaround bits. The first clock occurred when we clocked out the
     * last bit of the Register Address.
     */
    em_raise_mdi_clk(hw, &ctrl);
    em_lower_mdi_clk(hw, &ctrl);

    for(data = 0, i = 0; i < 16; i++) {
        data = data << 1;
        em_raise_mdi_clk(hw, &ctrl);
        ctrl = E1000_READ_REG(hw, CTRL);
        /* Check to see if we shifted in a "1". */
        if(ctrl & E1000_CTRL_MDIO) data |= 1;
        em_lower_mdi_clk(hw, &ctrl);
    }

    em_raise_mdi_clk(hw, &ctrl);
    em_lower_mdi_clk(hw, &ctrl);

    return data;
}

/*****************************************************************************
* Reads the value from a PHY register, if the value is on a specific non zero
* page, sets the page first.
* hw - Struct containing variables accessed by shared code
* reg_addr - address of the PHY register to read
******************************************************************************/
int32_t
em_read_phy_reg(struct em_hw *hw,
                   uint32_t reg_addr,
                   uint16_t *phy_data)
{
    uint32_t ret_val;

    DEBUGFUNC("em_read_phy_reg");

    if(hw->phy_type == em_phy_igp &&
       (reg_addr > MAX_PHY_MULTI_PAGE_REG)) {
        if((ret_val = em_write_phy_reg_ex(hw, IGP01E1000_PHY_PAGE_SELECT,
                                             (uint16_t)reg_addr)))
            return ret_val;
    }

    ret_val = em_read_phy_reg_ex(hw, IGP01E1000_PHY_PAGE_SELECT & reg_addr,
                                    phy_data);

    return ret_val;
}

int32_t
em_read_phy_reg_ex(struct em_hw *hw,
                      uint32_t reg_addr,
                      uint16_t *phy_data)
{
    uint32_t i;
    uint32_t mdic = 0;
    const uint32_t phy_addr = 1;

    DEBUGFUNC("em_read_phy_reg_ex");

    if(reg_addr > MAX_PHY_REG_ADDRESS) {
        DEBUGOUT1("PHY Address %d is out of range\n", reg_addr);
        return -E1000_ERR_PARAM;
    }

    if(hw->mac_type > em_82543) {
        /* Set up Op-code, Phy Address, and register address in the MDI
         * Control register.  The MAC will take care of interfacing with the
         * PHY to retrieve the desired data.
         */
        mdic = ((reg_addr << E1000_MDIC_REG_SHIFT) |
                (phy_addr << E1000_MDIC_PHY_SHIFT) |
                (E1000_MDIC_OP_READ));

        E1000_WRITE_REG(hw, MDIC, mdic);

        /* Poll the ready bit to see if the MDI read completed */
        for(i = 0; i < 64; i++) {
            usec_delay(50);
            mdic = E1000_READ_REG(hw, MDIC);
            if(mdic & E1000_MDIC_READY) break;
        }
        if(!(mdic & E1000_MDIC_READY)) {
            DEBUGOUT("MDI Read did not complete\n");
            return -E1000_ERR_PHY;
        }
        if(mdic & E1000_MDIC_ERROR) {
            DEBUGOUT("MDI Error\n");
            return -E1000_ERR_PHY;
        }
        *phy_data = (uint16_t) mdic;
    } else {
        /* We must first send a preamble through the MDIO pin to signal the
         * beginning of an MII instruction.  This is done by sending 32
         * consecutive "1" bits.
         */
        em_shift_out_mdi_bits(hw, PHY_PREAMBLE, PHY_PREAMBLE_SIZE);

        /* Now combine the next few fields that are required for a read
         * operation.  We use this method instead of calling the
         * em_shift_out_mdi_bits routine five different times. The format of
         * a MII read instruction consists of a shift out of 14 bits and is
         * defined as follows:
         *    <Preamble><SOF><Op Code><Phy Addr><Reg Addr>
         * followed by a shift in of 18 bits.  This first two bits shifted in
         * are TurnAround bits used to avoid contention on the MDIO pin when a
         * READ operation is performed.  These two bits are thrown away
         * followed by a shift in of 16 bits which contains the desired data.
         */
        mdic = ((reg_addr) | (phy_addr << 5) |
                (PHY_OP_READ << 10) | (PHY_SOF << 12));

        em_shift_out_mdi_bits(hw, mdic, 14);

        /* Now that we've shifted out the read command to the MII, we need to
         * "shift in" the 16-bit value (18 total bits) of the requested PHY
         * register address.
         */
        *phy_data = em_shift_in_mdi_bits(hw);
    }
    return E1000_SUCCESS;
}

/******************************************************************************
* Writes a value to a PHY register
*
* hw - Struct containing variables accessed by shared code
* reg_addr - address of the PHY register to write
* data - data to write to the PHY
******************************************************************************/
int32_t
em_write_phy_reg(struct em_hw *hw,
                    uint32_t reg_addr,
                    uint16_t phy_data)
{
    uint32_t ret_val;

    DEBUGFUNC("em_write_phy_reg");

    if(hw->phy_type == em_phy_igp &&
       (reg_addr > MAX_PHY_MULTI_PAGE_REG)) {
        if((ret_val = em_write_phy_reg_ex(hw, IGP01E1000_PHY_PAGE_SELECT,
                                             (uint16_t)reg_addr)))
            return ret_val;
    }

    ret_val = em_write_phy_reg_ex(hw, IGP01E1000_PHY_PAGE_SELECT & reg_addr,
                                     phy_data);

    return ret_val;
}

int32_t
em_write_phy_reg_ex(struct em_hw *hw,
                    uint32_t reg_addr,
                    uint16_t phy_data)
{
    uint32_t i;
    uint32_t mdic = 0;
    const uint32_t phy_addr = 1;

    DEBUGFUNC("em_write_phy_reg_ex");

    if(reg_addr > MAX_PHY_REG_ADDRESS) {
        DEBUGOUT1("PHY Address %d is out of range\n", reg_addr);
        return -E1000_ERR_PARAM;
    }

    if(hw->mac_type > em_82543) {
        /* Set up Op-code, Phy Address, register address, and data intended
         * for the PHY register in the MDI Control register.  The MAC will take
         * care of interfacing with the PHY to send the desired data.
         */
        mdic = (((uint32_t) phy_data) |
                (reg_addr << E1000_MDIC_REG_SHIFT) |
                (phy_addr << E1000_MDIC_PHY_SHIFT) |
                (E1000_MDIC_OP_WRITE));

        E1000_WRITE_REG(hw, MDIC, mdic);

        /* Poll the ready bit to see if the MDI read completed */
        for(i = 0; i < 64; i++) {
            usec_delay(50);
            mdic = E1000_READ_REG(hw, MDIC);
            if(mdic & E1000_MDIC_READY) break;
        }
        if(!(mdic & E1000_MDIC_READY)) {
            DEBUGOUT("MDI Write did not complete\n");
            return -E1000_ERR_PHY;
        }
    } else {
        /* We'll need to use the SW defined pins to shift the write command
         * out to the PHY. We first send a preamble to the PHY to signal the
         * beginning of the MII instruction.  This is done by sending 32
         * consecutive "1" bits.
         */
        em_shift_out_mdi_bits(hw, PHY_PREAMBLE, PHY_PREAMBLE_SIZE);

        /* Now combine the remaining required fields that will indicate a
         * write operation. We use this method instead of calling the
         * em_shift_out_mdi_bits routine for each field in the command. The
         * format of a MII write instruction is as follows:
         * <Preamble><SOF><Op Code><Phy Addr><Reg Addr><Turnaround><Data>.
         */
        mdic = ((PHY_TURNAROUND) | (reg_addr << 2) | (phy_addr << 7) |
                (PHY_OP_WRITE << 12) | (PHY_SOF << 14));
        mdic <<= 16;
        mdic |= (uint32_t) phy_data;

        em_shift_out_mdi_bits(hw, mdic, 32);
    }

    return E1000_SUCCESS;
}

/******************************************************************************
* Returns the PHY to the power-on reset state
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
void
em_phy_hw_reset(struct em_hw *hw)
{
    uint32_t ctrl, ctrl_ext;
    uint32_t led_ctrl;

    DEBUGFUNC("em_phy_hw_reset");

    DEBUGOUT("Resetting Phy...\n");

    if(hw->mac_type > em_82543) {
        /* Read the device control register and assert the E1000_CTRL_PHY_RST
         * bit. Then, take it out of reset.
         */
        ctrl = E1000_READ_REG(hw, CTRL);
        E1000_WRITE_REG(hw, CTRL, ctrl | E1000_CTRL_PHY_RST);
        E1000_WRITE_FLUSH(hw);
        msec_delay(10);
        E1000_WRITE_REG(hw, CTRL, ctrl);
        E1000_WRITE_FLUSH(hw);
    } else {
        /* Read the Extended Device Control Register, assert the PHY_RESET_DIR
         * bit to put the PHY into reset. Then, take it out of reset.
         */
        ctrl_ext = E1000_READ_REG(hw, CTRL_EXT);
        ctrl_ext |= E1000_CTRL_EXT_SDP4_DIR;
        ctrl_ext &= ~E1000_CTRL_EXT_SDP4_DATA;
        E1000_WRITE_REG(hw, CTRL_EXT, ctrl_ext);
        E1000_WRITE_FLUSH(hw);
        msec_delay(10);
        ctrl_ext |= E1000_CTRL_EXT_SDP4_DATA;
        E1000_WRITE_REG(hw, CTRL_EXT, ctrl_ext);
        E1000_WRITE_FLUSH(hw);
    }
    usec_delay(150);

    if((hw->mac_type == em_82541) || (hw->mac_type == em_82547)) {
        /* Configure activity LED after PHY reset */
        led_ctrl = E1000_READ_REG(hw, LEDCTL);
        led_ctrl &= IGP_ACTIVITY_LED_MASK;
        led_ctrl |= (IGP_ACTIVITY_LED_ENABLE | IGP_LED3_MODE);
        E1000_WRITE_REG(hw, LEDCTL, led_ctrl);
    }
}

/******************************************************************************
* Resets the PHY
*
* hw - Struct containing variables accessed by shared code
*
* Sets bit 15 of the MII Control regiser
******************************************************************************/
int32_t
em_phy_reset(struct em_hw *hw)
{
    int32_t ret_val;
    uint16_t phy_data;

    DEBUGFUNC("em_phy_reset");

    if(hw->mac_type != em_82541_rev_2) {
        if((ret_val = em_read_phy_reg(hw, PHY_CTRL, &phy_data)))
            return ret_val;

        phy_data |= MII_CR_RESET;
        if((ret_val = em_write_phy_reg(hw, PHY_CTRL, phy_data)))
            return ret_val;

        usec_delay(1);
    } else em_phy_hw_reset(hw);

    if(hw->phy_type == em_phy_igp)
        em_phy_init_script(hw);

    return E1000_SUCCESS;
}

/******************************************************************************
* Probes the expected PHY address for known PHY IDs
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
int32_t
em_detect_gig_phy(struct em_hw *hw)
{
    int32_t phy_init_status, ret_val;
    uint16_t phy_id_high, phy_id_low;
    boolean_t match = FALSE;

    DEBUGFUNC("em_detect_gig_phy");

    /* Read the PHY ID Registers to identify which PHY is onboard. */
    if((ret_val = em_read_phy_reg(hw, PHY_ID1, &phy_id_high)))
        return ret_val;

    hw->phy_id = (uint32_t) (phy_id_high << 16);
    usec_delay(20);
    if((ret_val = em_read_phy_reg(hw, PHY_ID2, &phy_id_low)))
        return ret_val;

    hw->phy_id |= (uint32_t) (phy_id_low & PHY_REVISION_MASK);
    hw->phy_revision = (uint32_t) phy_id_low & ~PHY_REVISION_MASK;

    switch(hw->mac_type) {
    case em_82543:
        if(hw->phy_id == M88E1000_E_PHY_ID) match = TRUE;
        break;
    case em_82544:
        if(hw->phy_id == M88E1000_I_PHY_ID) match = TRUE;
        break;
    case em_82540:
    case em_82545:
    case em_82545_rev_3:
    case em_82546:
    case em_82546_rev_3:
        if(hw->phy_id == M88E1011_I_PHY_ID) match = TRUE;
        break;
    case em_82541:
    case em_82541_rev_2:
    case em_82547:
    case em_82547_rev_2:
        if(hw->phy_id == IGP01E1000_I_PHY_ID) match = TRUE;
        break;
    default:
        DEBUGOUT1("Invalid MAC type %d\n", hw->mac_type);
        return -E1000_ERR_CONFIG;
    }
    phy_init_status = em_set_phy_type(hw);

    if ((match) && (phy_init_status == E1000_SUCCESS)) {
        DEBUGOUT1("PHY ID 0x%X detected\n", hw->phy_id);
        return E1000_SUCCESS;
    }
    DEBUGOUT1("Invalid PHY ID 0x%X\n", hw->phy_id);
    return -E1000_ERR_PHY;
}

/******************************************************************************
* Resets the PHY's DSP
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
static int32_t
em_phy_reset_dsp(struct em_hw *hw)
{
    int32_t ret_val;
    DEBUGFUNC("em_phy_reset_dsp");

    do {
        if((ret_val = em_write_phy_reg(hw, 29, 0x001d))) break;
        if((ret_val = em_write_phy_reg(hw, 30, 0x00c1))) break;
        if((ret_val = em_write_phy_reg(hw, 30, 0x0000))) break;
        ret_val = E1000_SUCCESS;
    } while(0);

    return ret_val;
}

/******************************************************************************
* Get PHY information from various PHY registers for igp PHY only.
*
* hw - Struct containing variables accessed by shared code
* phy_info - PHY information structure
******************************************************************************/
int32_t
em_phy_igp_get_info(struct em_hw *hw,
                       struct em_phy_info *phy_info)
{
    int32_t ret_val;
    uint16_t phy_data, polarity, min_length, max_length, average;

    DEBUGFUNC("em_phy_igp_get_info");

    /* The downshift status is checked only once, after link is established,
     * and it stored in the hw->speed_downgraded parameter. */
    phy_info->downshift = hw->speed_downgraded;

    /* IGP01E1000 does not need to support it. */
    phy_info->extended_10bt_distance = em_10bt_ext_dist_enable_normal;

    /* IGP01E1000 always correct polarity reversal */
    phy_info->polarity_correction = em_polarity_reversal_enabled;

    /* Check polarity status */
    if((ret_val = em_check_polarity(hw, &polarity)))
        return ret_val;

    phy_info->cable_polarity = polarity;

    if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_STATUS,
                                     &phy_data)))
        return ret_val;

    phy_info->mdix_mode = (phy_data & IGP01E1000_PSSR_MDIX) >>
                          IGP01E1000_PSSR_MDIX_SHIFT;

    if((phy_data & IGP01E1000_PSSR_SPEED_MASK) ==
       IGP01E1000_PSSR_SPEED_1000MBPS) {
        /* Local/Remote Receiver Information are only valid at 1000 Mbps */
        if((ret_val = em_read_phy_reg(hw, PHY_1000T_STATUS, &phy_data)))
            return ret_val;

        phy_info->local_rx = (phy_data & SR_1000T_LOCAL_RX_STATUS) >>
                             SR_1000T_LOCAL_RX_STATUS_SHIFT;
        phy_info->remote_rx = (phy_data & SR_1000T_REMOTE_RX_STATUS) >>
                              SR_1000T_REMOTE_RX_STATUS_SHIFT;

        /* Get cable length */
        if((ret_val = em_get_cable_length(hw, &min_length, &max_length)))
            return ret_val;

        /* transalte to old method */
        average = (max_length + min_length) / 2;

        if(average <= em_igp_cable_length_50)
            phy_info->cable_length = em_cable_length_50;
        else if(average <= em_igp_cable_length_80)
            phy_info->cable_length = em_cable_length_50_80;
        else if(average <= em_igp_cable_length_110)
            phy_info->cable_length = em_cable_length_80_110;
        else if(average <= em_igp_cable_length_140)
            phy_info->cable_length = em_cable_length_110_140;
        else
            phy_info->cable_length = em_cable_length_140;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
* Get PHY information from various PHY registers fot m88 PHY only.
*
* hw - Struct containing variables accessed by shared code
* phy_info - PHY information structure
******************************************************************************/
int32_t
em_phy_m88_get_info(struct em_hw *hw,
                       struct em_phy_info *phy_info)
{
    int32_t ret_val;
    uint16_t phy_data, polarity;

    DEBUGFUNC("em_phy_m88_get_info");

    /* The downshift status is checked only once, after link is established,
     * and it stored in the hw->speed_downgraded parameter. */
    phy_info->downshift = hw->speed_downgraded;

    if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_CTRL, &phy_data)))
        return ret_val;

    phy_info->extended_10bt_distance =
        (phy_data & M88E1000_PSCR_10BT_EXT_DIST_ENABLE) >>
        M88E1000_PSCR_10BT_EXT_DIST_ENABLE_SHIFT;
    phy_info->polarity_correction =
        (phy_data & M88E1000_PSCR_POLARITY_REVERSAL) >>
        M88E1000_PSCR_POLARITY_REVERSAL_SHIFT;

    /* Check polarity status */
    if((ret_val = em_check_polarity(hw, &polarity)))
        return ret_val;

    phy_info->cable_polarity = polarity;

    if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_STATUS, &phy_data)))
        return ret_val;

    phy_info->mdix_mode = (phy_data & M88E1000_PSSR_MDIX) >>
                          M88E1000_PSSR_MDIX_SHIFT;

    if(phy_data & M88E1000_PSSR_1000MBS) {
        /* Cable Length Estimation and Local/Remote Receiver Informatoion
         * are only valid at 1000 Mbps
         */
        phy_info->cable_length = ((phy_data & M88E1000_PSSR_CABLE_LENGTH) >>
                                  M88E1000_PSSR_CABLE_LENGTH_SHIFT);

        if((ret_val = em_read_phy_reg(hw, PHY_1000T_STATUS, &phy_data)))
            return ret_val;

        phy_info->local_rx = (phy_data & SR_1000T_LOCAL_RX_STATUS) >>
                             SR_1000T_LOCAL_RX_STATUS_SHIFT;

        phy_info->remote_rx = (phy_data & SR_1000T_REMOTE_RX_STATUS) >>
                              SR_1000T_REMOTE_RX_STATUS_SHIFT;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
* Get PHY information from various PHY registers
*
* hw - Struct containing variables accessed by shared code
* phy_info - PHY information structure
******************************************************************************/
int32_t
em_phy_get_info(struct em_hw *hw,
                   struct em_phy_info *phy_info)
{
    int32_t ret_val;
    uint16_t phy_data;

    DEBUGFUNC("em_phy_get_info");

    phy_info->cable_length = em_cable_length_undefined;
    phy_info->extended_10bt_distance = em_10bt_ext_dist_enable_undefined;
    phy_info->cable_polarity = em_rev_polarity_undefined;
    phy_info->downshift = em_downshift_undefined;
    phy_info->polarity_correction = em_polarity_reversal_undefined;
    phy_info->mdix_mode = em_auto_x_mode_undefined;
    phy_info->local_rx = em_1000t_rx_status_undefined;
    phy_info->remote_rx = em_1000t_rx_status_undefined;

    if(hw->media_type != em_media_type_copper) {
        DEBUGOUT("PHY info is only valid for copper media\n");
        return -E1000_ERR_CONFIG;
    }

    if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
        return ret_val;

    if((ret_val = em_read_phy_reg(hw, PHY_STATUS, &phy_data)))
        return ret_val;

    if((phy_data & MII_SR_LINK_STATUS) != MII_SR_LINK_STATUS) {
        DEBUGOUT("PHY info is only valid if link is up\n");
        return -E1000_ERR_CONFIG;
    }

    if(hw->phy_type == em_phy_igp)
        return em_phy_igp_get_info(hw, phy_info);
    else
        return em_phy_m88_get_info(hw, phy_info);
}

int32_t
em_validate_mdi_setting(struct em_hw *hw)
{
    DEBUGFUNC("em_validate_mdi_settings");

    if(!hw->autoneg && (hw->mdix == 0 || hw->mdix == 3)) {
        DEBUGOUT("Invalid MDI setting detected\n");
        hw->mdix = 1;
        return -E1000_ERR_CONFIG;
    }
    return E1000_SUCCESS;
}


/******************************************************************************
 * Sets up eeprom variables in the hw struct.  Must be called after mac_type
 * is configured.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
void
em_init_eeprom_params(struct em_hw *hw)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint32_t eecd = E1000_READ_REG(hw, EECD);
    uint16_t eeprom_size;

    DEBUGFUNC("em_init_eeprom_params");

    switch (hw->mac_type) {
    case em_82542_rev2_0:
    case em_82542_rev2_1:
    case em_82543:
    case em_82544:
        eeprom->type = em_eeprom_microwire;
        eeprom->word_size = 64;
        eeprom->opcode_bits = 3;
        eeprom->address_bits = 6;
        eeprom->delay_usec = 50;
        break;
    case em_82540:
    case em_82545:
    case em_82545_rev_3:
    case em_82546:
    case em_82546_rev_3:
        eeprom->type = em_eeprom_microwire;
        eeprom->opcode_bits = 3;
        eeprom->delay_usec = 50;
        if(eecd & E1000_EECD_SIZE) {
            eeprom->word_size = 256;
            eeprom->address_bits = 8;
        } else {
            eeprom->word_size = 64;
            eeprom->address_bits = 6;
        }
        break;
    case em_82541:
    case em_82541_rev_2:
    case em_82547:
    case em_82547_rev_2:
        if (eecd & E1000_EECD_TYPE) {
            eeprom->type = em_eeprom_spi;
            eeprom->opcode_bits = 8;
            eeprom->delay_usec = 1;
            if (eecd & E1000_EECD_ADDR_BITS) {
                eeprom->page_size = 32;
                eeprom->address_bits = 16;
            } else {
                eeprom->page_size = 8;
                eeprom->address_bits = 8;
            }
        } else {
            eeprom->type = em_eeprom_microwire;
            eeprom->opcode_bits = 3;
            eeprom->delay_usec = 50;
            if (eecd & E1000_EECD_ADDR_BITS) {
                eeprom->word_size = 256;
                eeprom->address_bits = 8;
            } else {
                eeprom->word_size = 64;
                eeprom->address_bits = 6;
            }
        }
        break;
    default:
        eeprom->type = em_eeprom_spi;
        eeprom->opcode_bits = 8;
        eeprom->delay_usec = 1;
        if (eecd & E1000_EECD_ADDR_BITS) {
            eeprom->page_size = 32;
            eeprom->address_bits = 16;
        } else {
            eeprom->page_size = 8;
            eeprom->address_bits = 8;
        }
        break;
    }

    if (eeprom->type == em_eeprom_spi) {
        eeprom->word_size = 64;
        if (em_read_eeprom(hw, EEPROM_CFG, 1, &eeprom_size) == 0) {
            eeprom_size &= EEPROM_SIZE_MASK;

            switch (eeprom_size) {
            case EEPROM_SIZE_16KB:
                eeprom->word_size = 8192;
                break;
            case EEPROM_SIZE_8KB:
                eeprom->word_size = 4096;
                break;
            case EEPROM_SIZE_4KB:
                eeprom->word_size = 2048;
                break;
            case EEPROM_SIZE_2KB:
                eeprom->word_size = 1024;
                break;
            case EEPROM_SIZE_1KB:
                eeprom->word_size = 512;
                break;
            case EEPROM_SIZE_512B:
                eeprom->word_size = 256;
                break;
            case EEPROM_SIZE_128B:
            default:
                eeprom->word_size = 64;
                break;
            }
        }
    }
}

/******************************************************************************
 * Raises the EEPROM's clock input.
 *
 * hw - Struct containing variables accessed by shared code
 * eecd - EECD's current value
 *****************************************************************************/
static void
em_raise_ee_clk(struct em_hw *hw,
                   uint32_t *eecd)
{
    /* Raise the clock input to the EEPROM (by setting the SK bit), and then
     * wait <delay> microseconds.
     */
    *eecd = *eecd | E1000_EECD_SK;
    E1000_WRITE_REG(hw, EECD, *eecd);
    E1000_WRITE_FLUSH(hw);
    usec_delay(hw->eeprom.delay_usec);
}

/******************************************************************************
 * Lowers the EEPROM's clock input.
 *
 * hw - Struct containing variables accessed by shared code
 * eecd - EECD's current value
 *****************************************************************************/
static void
em_lower_ee_clk(struct em_hw *hw,
                   uint32_t *eecd)
{
    /* Lower the clock input to the EEPROM (by clearing the SK bit), and then
     * wait 50 microseconds.
     */
    *eecd = *eecd & ~E1000_EECD_SK;
    E1000_WRITE_REG(hw, EECD, *eecd);
    E1000_WRITE_FLUSH(hw);
    usec_delay(hw->eeprom.delay_usec);
}

/******************************************************************************
 * Shift data bits out to the EEPROM.
 *
 * hw - Struct containing variables accessed by shared code
 * data - data to send to the EEPROM
 * count - number of bits to shift out
 *****************************************************************************/
static void
em_shift_out_ee_bits(struct em_hw *hw,
                        uint16_t data,
                        uint16_t count)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint32_t eecd;
    uint32_t mask;

    /* We need to shift "count" bits out to the EEPROM. So, value in the
     * "data" parameter will be shifted out to the EEPROM one bit at a time.
     * In order to do this, "data" must be broken down into bits.
     */
    mask = 0x01 << (count - 1);
    eecd = E1000_READ_REG(hw, EECD);
    if (eeprom->type == em_eeprom_microwire) {
        eecd &= ~E1000_EECD_DO;
    } else if (eeprom->type == em_eeprom_spi) {
        eecd |= E1000_EECD_DO;
    }
    do {
        /* A "1" is shifted out to the EEPROM by setting bit "DI" to a "1",
         * and then raising and then lowering the clock (the SK bit controls
         * the clock input to the EEPROM).  A "0" is shifted out to the EEPROM
         * by setting "DI" to "0" and then raising and then lowering the clock.
         */
        eecd &= ~E1000_EECD_DI;

        if(data & mask)
            eecd |= E1000_EECD_DI;

        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);

        usec_delay(eeprom->delay_usec);

        em_raise_ee_clk(hw, &eecd);
        em_lower_ee_clk(hw, &eecd);

        mask = mask >> 1;

    } while(mask);

    /* We leave the "DI" bit set to "0" when we leave this routine. */
    eecd &= ~E1000_EECD_DI;
    E1000_WRITE_REG(hw, EECD, eecd);
}

/******************************************************************************
 * Shift data bits in from the EEPROM
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
static uint16_t
em_shift_in_ee_bits(struct em_hw *hw,
                       uint16_t count)
{
    uint32_t eecd;
    uint32_t i;
    uint16_t data;

    /* In order to read a register from the EEPROM, we need to shift 'count'
     * bits in from the EEPROM. Bits are "shifted in" by raising the clock
     * input to the EEPROM (setting the SK bit), and then reading the value of
     * the "DO" bit.  During this "shifting in" process the "DI" bit should
     * always be clear.
     */

    eecd = E1000_READ_REG(hw, EECD);

    eecd &= ~(E1000_EECD_DO | E1000_EECD_DI);
    data = 0;

    for(i = 0; i < count; i++) {
        data = data << 1;
        em_raise_ee_clk(hw, &eecd);

        eecd = E1000_READ_REG(hw, EECD);

        eecd &= ~(E1000_EECD_DI);
        if(eecd & E1000_EECD_DO)
            data |= 1;

        em_lower_ee_clk(hw, &eecd);
    }

    return data;
}

/******************************************************************************
 * Prepares EEPROM for access
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Lowers EEPROM clock. Clears input pin. Sets the chip select pin. This
 * function should be called before issuing a command to the EEPROM.
 *****************************************************************************/
static int32_t
em_acquire_eeprom(struct em_hw *hw)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint32_t eecd, i=0;

    DEBUGFUNC("em_acquire_eeprom");

    eecd = E1000_READ_REG(hw, EECD);

    /* Request EEPROM Access */
    if(hw->mac_type > em_82544) {
        eecd |= E1000_EECD_REQ;
        E1000_WRITE_REG(hw, EECD, eecd);
        eecd = E1000_READ_REG(hw, EECD);
        while((!(eecd & E1000_EECD_GNT)) &&
              (i < E1000_EEPROM_GRANT_ATTEMPTS)) {
            i++;
            usec_delay(5);
            eecd = E1000_READ_REG(hw, EECD);
        }
        if(!(eecd & E1000_EECD_GNT)) {
            eecd &= ~E1000_EECD_REQ;
            E1000_WRITE_REG(hw, EECD, eecd);
            DEBUGOUT("Could not acquire EEPROM grant\n");
            return -E1000_ERR_EEPROM;
        }
    }

    /* Setup EEPROM for Read/Write */

    if (eeprom->type == em_eeprom_microwire) {
        /* Clear SK and DI */
        eecd &= ~(E1000_EECD_DI | E1000_EECD_SK);
        E1000_WRITE_REG(hw, EECD, eecd);

        /* Set CS */
        eecd |= E1000_EECD_CS;
        E1000_WRITE_REG(hw, EECD, eecd);
    } else if (eeprom->type == em_eeprom_spi) {
        /* Clear SK and CS */
        eecd &= ~(E1000_EECD_CS | E1000_EECD_SK);
        E1000_WRITE_REG(hw, EECD, eecd);
        usec_delay(1);
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Returns EEPROM to a "standby" state
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
static void
em_standby_eeprom(struct em_hw *hw)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint32_t eecd;

    eecd = E1000_READ_REG(hw, EECD);

    if(eeprom->type == em_eeprom_microwire) {
        eecd &= ~(E1000_EECD_CS | E1000_EECD_SK);
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(eeprom->delay_usec);

        /* Clock high */
        eecd |= E1000_EECD_SK;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(eeprom->delay_usec);

        /* Select EEPROM */
        eecd |= E1000_EECD_CS;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(eeprom->delay_usec);

        /* Clock low */
        eecd &= ~E1000_EECD_SK;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(eeprom->delay_usec);
    } else if(eeprom->type == em_eeprom_spi) {
        /* Toggle CS to flush commands */
        eecd |= E1000_EECD_CS;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(eeprom->delay_usec);
        eecd &= ~E1000_EECD_CS;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(eeprom->delay_usec);
    }
}

/******************************************************************************
 * Terminates a command by inverting the EEPROM's chip select pin
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
static void
em_release_eeprom(struct em_hw *hw)
{
    uint32_t eecd;

    DEBUGFUNC("em_release_eeprom");

    eecd = E1000_READ_REG(hw, EECD);

    if (hw->eeprom.type == em_eeprom_spi) {
        eecd |= E1000_EECD_CS;  /* Pull CS high */
        eecd &= ~E1000_EECD_SK; /* Lower SCK */

        E1000_WRITE_REG(hw, EECD, eecd);

        usec_delay(hw->eeprom.delay_usec);
    } else if(hw->eeprom.type == em_eeprom_microwire) {
        /* cleanup eeprom */

        /* CS on Microwire is active-high */
        eecd &= ~(E1000_EECD_CS | E1000_EECD_DI);

        E1000_WRITE_REG(hw, EECD, eecd);

        /* Rising edge of clock */
        eecd |= E1000_EECD_SK;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(hw->eeprom.delay_usec);

        /* Falling edge of clock */
        eecd &= ~E1000_EECD_SK;
        E1000_WRITE_REG(hw, EECD, eecd);
        E1000_WRITE_FLUSH(hw);
        usec_delay(hw->eeprom.delay_usec);
    }

    /* Stop requesting EEPROM access */
    if(hw->mac_type > em_82544) {
        eecd &= ~E1000_EECD_REQ;
        E1000_WRITE_REG(hw, EECD, eecd);
    }
}

/******************************************************************************
 * Reads a 16 bit word from the EEPROM.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_spi_eeprom_ready(struct em_hw *hw)
{
    uint16_t retry_count = 0;
    uint8_t spi_stat_reg;

    DEBUGFUNC("em_spi_eeprom_ready");

    /* Read "Status Register" repeatedly until the LSB is cleared.  The
     * EEPROM will signal that the command has been completed by clearing
     * bit 0 of the internal status register.  If it's not cleared within
     * 5 milliseconds, then error out.
     */
    retry_count = 0;
    do {
        em_shift_out_ee_bits(hw, EEPROM_RDSR_OPCODE_SPI,
                                hw->eeprom.opcode_bits);
        spi_stat_reg = (uint8_t)em_shift_in_ee_bits(hw, 8);
        if (!(spi_stat_reg & EEPROM_STATUS_RDY_SPI))
            break;

        usec_delay(5);
        retry_count += 5;

    } while(retry_count < EEPROM_MAX_RETRY_SPI);

    /* ATMEL SPI write time could vary from 0-20mSec on 3.3V devices (and
     * only 0-5mSec on 5V devices)
     */
    if(retry_count >= EEPROM_MAX_RETRY_SPI) {
        DEBUGOUT("SPI EEPROM Status error\n");
        return -E1000_ERR_EEPROM;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Reads a 16 bit word from the EEPROM.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - offset of  word in the EEPROM to read
 * data - word read from the EEPROM
 * words - number of words to read
 *****************************************************************************/
int32_t
em_read_eeprom(struct em_hw *hw,
                  uint16_t offset,
                  uint16_t words,
                  uint16_t *data)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint32_t i = 0;

    DEBUGFUNC("em_read_eeprom");

    /* A check for invalid values:  offset too large, too many words, and not
     * enough words.
     */
    if((offset > eeprom->word_size) || (words > eeprom->word_size - offset) ||
       (words == 0)) {
        DEBUGOUT("\"words\" parameter out of bounds\n");
        return -E1000_ERR_EEPROM;
    }

    /* Prepare the EEPROM for reading  */
    if(em_acquire_eeprom(hw) != E1000_SUCCESS)
        return -E1000_ERR_EEPROM;

    if(eeprom->type == em_eeprom_spi) {
        uint16_t word_in;
        uint8_t read_opcode = EEPROM_READ_OPCODE_SPI;

        if(em_spi_eeprom_ready(hw)) {
            em_release_eeprom(hw);
            return -E1000_ERR_EEPROM;
        }

        em_standby_eeprom(hw);

        /* Some SPI eeproms use the 8th address bit embedded in the opcode */
        if((eeprom->address_bits == 8) && (offset >= 128))
            read_opcode |= EEPROM_A8_OPCODE_SPI;

        /* Send the READ command (opcode + addr)  */
        em_shift_out_ee_bits(hw, read_opcode, eeprom->opcode_bits);
        em_shift_out_ee_bits(hw, (uint16_t)(offset*2), eeprom->address_bits);

        /* Read the data.  The address of the eeprom internally increments with
         * each byte (spi) being read, saving on the overhead of eeprom setup
         * and tear-down.  The address counter will roll over if reading beyond
         * the size of the eeprom, thus allowing the entire memory to be read
         * starting from any offset. */
        for (i = 0; i < words; i++) {
            word_in = em_shift_in_ee_bits(hw, 16);
            data[i] = (word_in >> 8) | (word_in << 8);
        }
    } else if(eeprom->type == em_eeprom_microwire) {
        for (i = 0; i < words; i++) {
            /* Send the READ command (opcode + addr)  */
            em_shift_out_ee_bits(hw, EEPROM_READ_OPCODE_MICROWIRE,
                                    eeprom->opcode_bits);
            em_shift_out_ee_bits(hw, (uint16_t)(offset + i),
                                    eeprom->address_bits);

            /* Read the data.  For microwire, each word requires the overhead
             * of eeprom setup and tear-down. */
            data[i] = em_shift_in_ee_bits(hw, 16);
            em_standby_eeprom(hw);
        }
    }

    /* End this read operation */
    em_release_eeprom(hw);

    return E1000_SUCCESS;
}

/******************************************************************************
 * Verifies that the EEPROM has a valid checksum
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Reads the first 64 16 bit words of the EEPROM and sums the values read.
 * If the the sum of the 64 16 bit words is 0xBABA, the EEPROM's checksum is
 * valid.
 *****************************************************************************/
int32_t
em_validate_eeprom_checksum(struct em_hw *hw)
{
    uint16_t checksum = 0;
    uint16_t i, eeprom_data;

    DEBUGFUNC("em_validate_eeprom_checksum");

    for(i = 0; i < (EEPROM_CHECKSUM_REG + 1); i++) {
        if(em_read_eeprom(hw, i, 1, &eeprom_data) < 0) {
            DEBUGOUT("EEPROM Read Error\n");
            return -E1000_ERR_EEPROM;
        }
        checksum += eeprom_data;
    }

    if(checksum == (uint16_t) EEPROM_SUM)
        return E1000_SUCCESS;
    else {
        DEBUGOUT("EEPROM Checksum Invalid\n");
        return -E1000_ERR_EEPROM;
    }
}

/******************************************************************************
 * Calculates the EEPROM checksum and writes it to the EEPROM
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Sums the first 63 16 bit words of the EEPROM. Subtracts the sum from 0xBABA.
 * Writes the difference to word offset 63 of the EEPROM.
 *****************************************************************************/
int32_t
em_update_eeprom_checksum(struct em_hw *hw)
{
    uint16_t checksum = 0;
    uint16_t i, eeprom_data;

    DEBUGFUNC("em_update_eeprom_checksum");

    for(i = 0; i < EEPROM_CHECKSUM_REG; i++) {
        if(em_read_eeprom(hw, i, 1, &eeprom_data) < 0) {
            DEBUGOUT("EEPROM Read Error\n");
            return -E1000_ERR_EEPROM;
        }
        checksum += eeprom_data;
    }
    checksum = (uint16_t) EEPROM_SUM - checksum;
    if(em_write_eeprom(hw, EEPROM_CHECKSUM_REG, 1, &checksum) < 0) {
        DEBUGOUT("EEPROM Write Error\n");
        return -E1000_ERR_EEPROM;
    }
    return E1000_SUCCESS;
}

/******************************************************************************
 * Parent function for writing words to the different EEPROM types.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - offset within the EEPROM to be written to
 * words - number of words to write
 * data - 16 bit word to be written to the EEPROM
 *
 * If em_update_eeprom_checksum is not called after this function, the
 * EEPROM will most likely contain an invalid checksum.
 *****************************************************************************/
int32_t
em_write_eeprom(struct em_hw *hw,
                   uint16_t offset,
                   uint16_t words,
                   uint16_t *data)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    int32_t status = 0;

    DEBUGFUNC("em_write_eeprom");

    /* A check for invalid values:  offset too large, too many words, and not
     * enough words.
     */
    if((offset > eeprom->word_size) || (words > eeprom->word_size - offset) ||
       (words == 0)) {
        DEBUGOUT("\"words\" parameter out of bounds\n");
        return -E1000_ERR_EEPROM;
    }

    /* Prepare the EEPROM for writing  */
    if (em_acquire_eeprom(hw) != E1000_SUCCESS)
        return -E1000_ERR_EEPROM;

    if(eeprom->type == em_eeprom_microwire)
        status = em_write_eeprom_microwire(hw, offset, words, data);
    else
        status = em_write_eeprom_spi(hw, offset, words, data);

    /* Done with writing */
    em_release_eeprom(hw);

    return status;
}

/******************************************************************************
 * Writes a 16 bit word to a given offset in an SPI EEPROM.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - offset within the EEPROM to be written to
 * words - number of words to write
 * data - pointer to array of 8 bit words to be written to the EEPROM
 *
 *****************************************************************************/
int32_t
em_write_eeprom_spi(struct em_hw *hw,
                       uint16_t offset,
                       uint16_t words,
                       uint16_t *data)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint16_t widx = 0;

    DEBUGFUNC("em_write_eeprom_spi");

    while (widx < words) {
        uint8_t write_opcode = EEPROM_WRITE_OPCODE_SPI;

        if(em_spi_eeprom_ready(hw)) return -E1000_ERR_EEPROM;

        em_standby_eeprom(hw);

        /*  Send the WRITE ENABLE command (8 bit opcode )  */
        em_shift_out_ee_bits(hw, EEPROM_WREN_OPCODE_SPI,
                                    eeprom->opcode_bits);

        em_standby_eeprom(hw);

        /* Some SPI eeproms use the 8th address bit embedded in the opcode */
        if((eeprom->address_bits == 8) && (offset >= 128))
            write_opcode |= EEPROM_A8_OPCODE_SPI;

        /* Send the Write command (8-bit opcode + addr) */
        em_shift_out_ee_bits(hw, write_opcode, eeprom->opcode_bits);

        em_shift_out_ee_bits(hw, (uint16_t)((offset + widx)*2),
                                eeprom->address_bits);

        /* Send the data */

        /* Loop to allow for up to whole page write (32 bytes) of eeprom */
        while (widx < words) {
            uint16_t word_out = data[widx];
            word_out = (word_out >> 8) | (word_out << 8);
            em_shift_out_ee_bits(hw, word_out, 16);
            widx++;

            /* Some larger eeprom sizes are capable of a 32-byte PAGE WRITE
             * operation, while the smaller eeproms are capable of an 8-byte
             * PAGE WRITE operation.  Break the inner loop to pass new address
             */
            if((((offset + widx)*2) % eeprom->page_size) == 0) {
                em_standby_eeprom(hw);
                break;
            }
        }
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Writes a 16 bit word to a given offset in a Microwire EEPROM.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - offset within the EEPROM to be written to
 * words - number of words to write
 * data - pointer to array of 16 bit words to be written to the EEPROM
 *
 *****************************************************************************/
int32_t
em_write_eeprom_microwire(struct em_hw *hw,
                             uint16_t offset,
                             uint16_t words,
                             uint16_t *data)
{
    struct em_eeprom_info *eeprom = &hw->eeprom;
    uint32_t eecd;
    uint16_t words_written = 0;
    uint16_t i = 0;

    DEBUGFUNC("em_write_eeprom_microwire");

    /* Send the write enable command to the EEPROM (3-bit opcode plus
     * 6/8-bit dummy address beginning with 11).  It's less work to include
     * the 11 of the dummy address as part of the opcode than it is to shift
     * it over the correct number of bits for the address.  This puts the
     * EEPROM into write/erase mode.
     */
    em_shift_out_ee_bits(hw, EEPROM_EWEN_OPCODE_MICROWIRE,
                            (uint16_t)(eeprom->opcode_bits + 2));

    em_shift_out_ee_bits(hw, 0, (uint16_t)(eeprom->address_bits - 2));

    /* Prepare the EEPROM */
    em_standby_eeprom(hw);

    while (words_written < words) {
        /* Send the Write command (3-bit opcode + addr) */
        em_shift_out_ee_bits(hw, EEPROM_WRITE_OPCODE_MICROWIRE,
                                eeprom->opcode_bits);

        em_shift_out_ee_bits(hw, (uint16_t)(offset + words_written),
                                eeprom->address_bits);

        /* Send the data */
        em_shift_out_ee_bits(hw, data[words_written], 16);

        /* Toggle the CS line.  This in effect tells the EEPROM to execute
         * the previous command.
         */
        em_standby_eeprom(hw);

        /* Read DO repeatedly until it is high (equal to '1').  The EEPROM will
         * signal that the command has been completed by raising the DO signal.
         * If DO does not go high in 10 milliseconds, then error out.
         */
        for(i = 0; i < 200; i++) {
            eecd = E1000_READ_REG(hw, EECD);
            if(eecd & E1000_EECD_DO) break;
            usec_delay(50);
        }
        if(i == 200) {
            DEBUGOUT("EEPROM Write did not complete\n");
            return -E1000_ERR_EEPROM;
        }

        /* Recover from write */
        em_standby_eeprom(hw);

        words_written++;
    }

    /* Send the write disable command to the EEPROM (3-bit opcode plus
     * 6/8-bit dummy address beginning with 10).  It's less work to include
     * the 10 of the dummy address as part of the opcode than it is to shift
     * it over the correct number of bits for the address.  This takes the
     * EEPROM out of write/erase mode.
     */
    em_shift_out_ee_bits(hw, EEPROM_EWDS_OPCODE_MICROWIRE,
                            (uint16_t)(eeprom->opcode_bits + 2));

    em_shift_out_ee_bits(hw, 0, (uint16_t)(eeprom->address_bits - 2));

    return E1000_SUCCESS;
}

/******************************************************************************
 * Reads the adapter's part number from the EEPROM
 *
 * hw - Struct containing variables accessed by shared code
 * part_num - Adapter's part number
 *****************************************************************************/
int32_t
em_read_part_num(struct em_hw *hw,
                    uint32_t *part_num)
{
    uint16_t offset = EEPROM_PBA_BYTE_1;
    uint16_t eeprom_data;

    DEBUGFUNC("em_read_part_num");

    /* Get word 0 from EEPROM */
    if(em_read_eeprom(hw, offset, 1, &eeprom_data) < 0) {
        DEBUGOUT("EEPROM Read Error\n");
        return -E1000_ERR_EEPROM;
    }
    /* Save word 0 in upper half of part_num */
    *part_num = (uint32_t) (eeprom_data << 16);

    /* Get word 1 from EEPROM */
    if(em_read_eeprom(hw, ++offset, 1, &eeprom_data) < 0) {
        DEBUGOUT("EEPROM Read Error\n");
        return -E1000_ERR_EEPROM;
    }
    /* Save word 1 in lower half of part_num */
    *part_num |= eeprom_data;

    return E1000_SUCCESS;
}

/******************************************************************************
 * Reads the adapter's MAC address from the EEPROM and inverts the LSB for the
 * second function of dual function devices
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_read_mac_addr(struct em_hw * hw)
{
    uint16_t offset;
    uint16_t eeprom_data, i;

    DEBUGFUNC("em_read_mac_addr");

    for(i = 0; i < NODE_ADDRESS_SIZE; i += 2) {
        offset = i >> 1;
        if(em_read_eeprom(hw, offset, 1, &eeprom_data) < 0) {
            DEBUGOUT("EEPROM Read Error\n");
            return -E1000_ERR_EEPROM;
        }
        hw->perm_mac_addr[i] = (uint8_t) (eeprom_data & 0x00FF);
        hw->perm_mac_addr[i+1] = (uint8_t) (eeprom_data >> 8);
    }
    if(((hw->mac_type == em_82546) || (hw->mac_type == em_82546_rev_3)) &&
       (E1000_READ_REG(hw, STATUS) & E1000_STATUS_FUNC_1)) {
        if(hw->perm_mac_addr[5] & 0x01)
            hw->perm_mac_addr[5] &= ~(0x01);
        else
            hw->perm_mac_addr[5] |= 0x01;
    }
    for(i = 0; i < NODE_ADDRESS_SIZE; i++)
        hw->mac_addr[i] = hw->perm_mac_addr[i];
    return E1000_SUCCESS;
}

/******************************************************************************
 * Initializes receive address filters.
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Places the MAC address in receive address register 0 and clears the rest
 * of the receive addresss registers. Clears the multicast table. Assumes
 * the receiver is in reset when the routine is called.
 *****************************************************************************/
void
em_init_rx_addrs(struct em_hw *hw)
{
    uint32_t i;
    uint32_t addr_low;
    uint32_t addr_high;

    DEBUGFUNC("em_init_rx_addrs");

    /* Setup the receive address. */
    DEBUGOUT("Programming MAC Address into RAR[0]\n");
    addr_low = (hw->mac_addr[0] |
                (hw->mac_addr[1] << 8) |
                (hw->mac_addr[2] << 16) | (hw->mac_addr[3] << 24));

    addr_high = (hw->mac_addr[4] |
                 (hw->mac_addr[5] << 8) | E1000_RAH_AV);

    E1000_WRITE_REG_ARRAY(hw, RA, 0, addr_low);
    E1000_WRITE_REG_ARRAY(hw, RA, 1, addr_high);

    /* Zero out the other 15 receive addresses. */
    DEBUGOUT("Clearing RAR[1-15]\n");
    for(i = 1; i < E1000_RAR_ENTRIES; i++) {
        E1000_WRITE_REG_ARRAY(hw, RA, (i << 1), 0);
        E1000_WRITE_REG_ARRAY(hw, RA, ((i << 1) + 1), 0);
    }
}

/******************************************************************************
 * Updates the MAC's list of multicast addresses.
 *
 * hw - Struct containing variables accessed by shared code
 * mc_addr_list - the list of new multicast addresses
 * mc_addr_count - number of addresses
 * pad - number of bytes between addresses in the list
 *
 * The given list replaces any existing list. Clears the last 15 receive
 * address registers and the multicast table. Uses receive address registers
 * for the first 15 multicast addresses, and hashes the rest into the
 * multicast table.
 *****************************************************************************/
void
em_mc_addr_list_update(struct em_hw *hw,
                          uint8_t *mc_addr_list,
                          uint32_t mc_addr_count,
                          uint32_t pad)
{
    uint32_t hash_value;
    uint32_t i;
    uint32_t rar_used_count = 1; /* RAR[0] is used for our MAC address */

    DEBUGFUNC("em_mc_addr_list_update");

    /* Set the new number of MC addresses that we are being requested to use. */
    hw->num_mc_addrs = mc_addr_count;

    /* Clear RAR[1-15] */
    DEBUGOUT(" Clearing RAR[1-15]\n");
    for(i = rar_used_count; i < E1000_RAR_ENTRIES; i++) {
        E1000_WRITE_REG_ARRAY(hw, RA, (i << 1), 0);
        E1000_WRITE_REG_ARRAY(hw, RA, ((i << 1) + 1), 0);
    }

    /* Clear the MTA */
    DEBUGOUT(" Clearing MTA\n");
    for(i = 0; i < E1000_NUM_MTA_REGISTERS; i++) {
        E1000_WRITE_REG_ARRAY(hw, MTA, i, 0);
    }

    /* Add the new addresses */
    for(i = 0; i < mc_addr_count; i++) {
        DEBUGOUT(" Adding the multicast addresses:\n");
        DEBUGOUT7(" MC Addr #%d =%.2X %.2X %.2X %.2X %.2X %.2X\n", i,
                  mc_addr_list[i * (ETH_LENGTH_OF_ADDRESS + pad)],
                  mc_addr_list[i * (ETH_LENGTH_OF_ADDRESS + pad) + 1],
                  mc_addr_list[i * (ETH_LENGTH_OF_ADDRESS + pad) + 2],
                  mc_addr_list[i * (ETH_LENGTH_OF_ADDRESS + pad) + 3],
                  mc_addr_list[i * (ETH_LENGTH_OF_ADDRESS + pad) + 4],
                  mc_addr_list[i * (ETH_LENGTH_OF_ADDRESS + pad) + 5]);

        hash_value = em_hash_mc_addr(hw,
                                        mc_addr_list +
                                        (i * (ETH_LENGTH_OF_ADDRESS + pad)));

        DEBUGOUT1(" Hash value = 0x%03X\n", hash_value);

        /* Place this multicast address in the RAR if there is room, *
         * else put it in the MTA
         */
        if(rar_used_count < E1000_RAR_ENTRIES) {
            em_rar_set(hw,
                          mc_addr_list + (i * (ETH_LENGTH_OF_ADDRESS + pad)),
                          rar_used_count);
            rar_used_count++;
        } else {
            em_mta_set(hw, hash_value);
        }
    }
    DEBUGOUT("MC Update Complete\n");
}

/******************************************************************************
 * Hashes an address to determine its location in the multicast table
 *
 * hw - Struct containing variables accessed by shared code
 * mc_addr - the multicast address to hash
 *****************************************************************************/
uint32_t
em_hash_mc_addr(struct em_hw *hw,
                   uint8_t *mc_addr)
{
    uint32_t hash_value = 0;

    /* The portion of the address that is used for the hash table is
     * determined by the mc_filter_type setting.
     */
    switch (hw->mc_filter_type) {
    /* [0] [1] [2] [3] [4] [5]
     * 01  AA  00  12  34  56
     * LSB                 MSB
     */
    case 0:
        /* [47:36] i.e. 0x563 for above example address */
        hash_value = ((mc_addr[4] >> 4) | (((uint16_t) mc_addr[5]) << 4));
        break;
    case 1:
        /* [46:35] i.e. 0xAC6 for above example address */
        hash_value = ((mc_addr[4] >> 3) | (((uint16_t) mc_addr[5]) << 5));
        break;
    case 2:
        /* [45:34] i.e. 0x5D8 for above example address */
        hash_value = ((mc_addr[4] >> 2) | (((uint16_t) mc_addr[5]) << 6));
        break;
    case 3:
        /* [43:32] i.e. 0x634 for above example address */
        hash_value = ((mc_addr[4]) | (((uint16_t) mc_addr[5]) << 8));
        break;
    }

    hash_value &= 0xFFF;
    return hash_value;
}

/******************************************************************************
 * Sets the bit in the multicast table corresponding to the hash value.
 *
 * hw - Struct containing variables accessed by shared code
 * hash_value - Multicast address hash value
 *****************************************************************************/
void
em_mta_set(struct em_hw *hw,
              uint32_t hash_value)
{
    uint32_t hash_bit, hash_reg;
    uint32_t mta;
    uint32_t temp;

    /* The MTA is a register array of 128 32-bit registers.
     * It is treated like an array of 4096 bits.  We want to set
     * bit BitArray[hash_value]. So we figure out what register
     * the bit is in, read it, OR in the new bit, then write
     * back the new value.  The register is determined by the
     * upper 7 bits of the hash value and the bit within that
     * register are determined by the lower 5 bits of the value.
     */
    hash_reg = (hash_value >> 5) & 0x7F;
    hash_bit = hash_value & 0x1F;

    mta = E1000_READ_REG_ARRAY(hw, MTA, hash_reg);

    mta |= (1 << hash_bit);

    /* If we are on an 82544 and we are trying to write an odd offset
     * in the MTA, save off the previous entry before writing and
     * restore the old value after writing.
     */
    if((hw->mac_type == em_82544) && ((hash_reg & 0x1) == 1)) {
        temp = E1000_READ_REG_ARRAY(hw, MTA, (hash_reg - 1));
        E1000_WRITE_REG_ARRAY(hw, MTA, hash_reg, mta);
        E1000_WRITE_REG_ARRAY(hw, MTA, (hash_reg - 1), temp);
    } else {
        E1000_WRITE_REG_ARRAY(hw, MTA, hash_reg, mta);
    }
}

/******************************************************************************
 * Puts an ethernet address into a receive address register.
 *
 * hw - Struct containing variables accessed by shared code
 * addr - Address to put into receive address register
 * index - Receive address register to write
 *****************************************************************************/
void
em_rar_set(struct em_hw *hw,
              uint8_t *addr,
              uint32_t index)
{
    uint32_t rar_low, rar_high;

    /* HW expects these in little endian so we reverse the byte order
     * from network order (big endian) to little endian
     */
    rar_low = ((uint32_t) addr[0] |
               ((uint32_t) addr[1] << 8) |
               ((uint32_t) addr[2] << 16) | ((uint32_t) addr[3] << 24));

    rar_high = ((uint32_t) addr[4] | ((uint32_t) addr[5] << 8) | E1000_RAH_AV);

    E1000_WRITE_REG_ARRAY(hw, RA, (index << 1), rar_low);
    E1000_WRITE_REG_ARRAY(hw, RA, ((index << 1) + 1), rar_high);
}

/******************************************************************************
 * Writes a value to the specified offset in the VLAN filter table.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - Offset in VLAN filer table to write
 * value - Value to write into VLAN filter table
 *****************************************************************************/
void
em_write_vfta(struct em_hw *hw,
                 uint32_t offset,
                 uint32_t value)
{
    uint32_t temp;

    if((hw->mac_type == em_82544) && ((offset & 0x1) == 1)) {
        temp = E1000_READ_REG_ARRAY(hw, VFTA, (offset - 1));
        E1000_WRITE_REG_ARRAY(hw, VFTA, offset, value);
        E1000_WRITE_REG_ARRAY(hw, VFTA, (offset - 1), temp);
    } else {
        E1000_WRITE_REG_ARRAY(hw, VFTA, offset, value);
    }
}

/******************************************************************************
 * Clears the VLAN filer table
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
void
em_clear_vfta(struct em_hw *hw)
{
    uint32_t offset;

    for(offset = 0; offset < E1000_VLAN_FILTER_TBL_SIZE; offset++)
        E1000_WRITE_REG_ARRAY(hw, VFTA, offset, 0);
}

static int32_t
em_id_led_init(struct em_hw * hw)
{
    uint32_t ledctl;
    const uint32_t ledctl_mask = 0x000000FF;
    const uint32_t ledctl_on = E1000_LEDCTL_MODE_LED_ON;
    const uint32_t ledctl_off = E1000_LEDCTL_MODE_LED_OFF;
    uint16_t eeprom_data, i, temp;
    const uint16_t led_mask = 0x0F;

    DEBUGFUNC("em_id_led_init");

    if(hw->mac_type < em_82540) {
        /* Nothing to do */
        return E1000_SUCCESS;
    }

    ledctl = E1000_READ_REG(hw, LEDCTL);
    hw->ledctl_default = ledctl;
    hw->ledctl_mode1 = hw->ledctl_default;
    hw->ledctl_mode2 = hw->ledctl_default;

    if(em_read_eeprom(hw, EEPROM_ID_LED_SETTINGS, 1, &eeprom_data) < 0) {
        DEBUGOUT("EEPROM Read Error\n");
        return -E1000_ERR_EEPROM;
    }
    if((eeprom_data== ID_LED_RESERVED_0000) ||
       (eeprom_data == ID_LED_RESERVED_FFFF)) eeprom_data = ID_LED_DEFAULT;
    for(i = 0; i < 4; i++) {
        temp = (eeprom_data >> (i << 2)) & led_mask;
        switch(temp) {
        case ID_LED_ON1_DEF2:
        case ID_LED_ON1_ON2:
        case ID_LED_ON1_OFF2:
            hw->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
            hw->ledctl_mode1 |= ledctl_on << (i << 3);
            break;
        case ID_LED_OFF1_DEF2:
        case ID_LED_OFF1_ON2:
        case ID_LED_OFF1_OFF2:
            hw->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
            hw->ledctl_mode1 |= ledctl_off << (i << 3);
            break;
        default:
            /* Do nothing */
            break;
        }
        switch(temp) {
        case ID_LED_DEF1_ON2:
        case ID_LED_ON1_ON2:
        case ID_LED_OFF1_ON2:
            hw->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
            hw->ledctl_mode2 |= ledctl_on << (i << 3);
            break;
        case ID_LED_DEF1_OFF2:
        case ID_LED_ON1_OFF2:
        case ID_LED_OFF1_OFF2:
            hw->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
            hw->ledctl_mode2 |= ledctl_off << (i << 3);
            break;
        default:
            /* Do nothing */
            break;
        }
    }
    return E1000_SUCCESS;
}

/******************************************************************************
 * Prepares SW controlable LED for use and saves the current state of the LED.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_setup_led(struct em_hw *hw)
{
    uint32_t ledctl;
    int32_t ret_val = E1000_SUCCESS;

    DEBUGFUNC("em_setup_led");

    switch(hw->mac_type) {
    case em_82542_rev2_0:
    case em_82542_rev2_1:
    case em_82543:
    case em_82544:
        /* No setup necessary */
        break;
    case em_82541:
    case em_82547:
    case em_82541_rev_2:
    case em_82547_rev_2:
        /* Turn off PHY Smart Power Down (if enabled) */
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_GMII_FIFO,
                                         &hw->phy_spd_default)))
            return ret_val;
        if((ret_val = em_write_phy_reg(hw, IGP01E1000_GMII_FIFO,
                                          (uint16_t)(hw->phy_spd_default &
                                          ~IGP01E1000_GMII_SPD))))
            return ret_val;
        /* Fall Through */
    default:
        if(hw->media_type == em_media_type_fiber) {
            ledctl = E1000_READ_REG(hw, LEDCTL);
            /* Save current LEDCTL settings */
            hw->ledctl_default = ledctl;
            /* Turn off LED0 */
            ledctl &= ~(E1000_LEDCTL_LED0_IVRT |
                        E1000_LEDCTL_LED0_BLINK |
                        E1000_LEDCTL_LED0_MODE_MASK);
            ledctl |= (E1000_LEDCTL_MODE_LED_OFF <<
                       E1000_LEDCTL_LED0_MODE_SHIFT);
            E1000_WRITE_REG(hw, LEDCTL, ledctl);
        } else if(hw->media_type == em_media_type_copper)
            E1000_WRITE_REG(hw, LEDCTL, hw->ledctl_mode1);
        break;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Restores the saved state of the SW controlable LED.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_cleanup_led(struct em_hw *hw)
{
    int32_t ret_val = E1000_SUCCESS;

    DEBUGFUNC("em_cleanup_led");

    switch(hw->mac_type) {
    case em_82542_rev2_0:
    case em_82542_rev2_1:
    case em_82543:
    case em_82544:
        /* No cleanup necessary */
        break;
    case em_82541:
    case em_82547:
    case em_82541_rev_2:
    case em_82547_rev_2:
        /* Turn on PHY Smart Power Down (if previously enabled) */
        if((ret_val = em_write_phy_reg(hw, IGP01E1000_GMII_FIFO,
                                          hw->phy_spd_default)))
            return ret_val;
        /* Fall Through */
    default:
        /* Restore LEDCTL settings */
        E1000_WRITE_REG(hw, LEDCTL, hw->ledctl_default);
        break;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Turns on the software controllable LED
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_led_on(struct em_hw *hw)
{
    uint32_t ctrl = E1000_READ_REG(hw, CTRL);

    DEBUGFUNC("em_led_on");

    switch(hw->mac_type) {
    case em_82542_rev2_0:
    case em_82542_rev2_1:
    case em_82543:
        /* Set SW Defineable Pin 0 to turn on the LED */
        ctrl |= E1000_CTRL_SWDPIN0;
        ctrl |= E1000_CTRL_SWDPIO0;
        break;
    case em_82544:
        if(hw->media_type == em_media_type_fiber) {
            /* Set SW Defineable Pin 0 to turn on the LED */
            ctrl |= E1000_CTRL_SWDPIN0;
            ctrl |= E1000_CTRL_SWDPIO0;
        } else {
            /* Clear SW Defineable Pin 0 to turn on the LED */
            ctrl &= ~E1000_CTRL_SWDPIN0;
            ctrl |= E1000_CTRL_SWDPIO0;
        }
        break;
    default:
        if(hw->media_type == em_media_type_fiber) {
            /* Clear SW Defineable Pin 0 to turn on the LED */
            ctrl &= ~E1000_CTRL_SWDPIN0;
            ctrl |= E1000_CTRL_SWDPIO0;
        } else if(hw->media_type == em_media_type_copper) {
            E1000_WRITE_REG(hw, LEDCTL, hw->ledctl_mode2);
            return E1000_SUCCESS;
        }
        break;
    }

    E1000_WRITE_REG(hw, CTRL, ctrl);

    return E1000_SUCCESS;
}

/******************************************************************************
 * Turns off the software controllable LED
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
int32_t
em_led_off(struct em_hw *hw)
{
    uint32_t ctrl = E1000_READ_REG(hw, CTRL);

    DEBUGFUNC("em_led_off");

    switch(hw->mac_type) {
    case em_82542_rev2_0:
    case em_82542_rev2_1:
    case em_82543:
        /* Clear SW Defineable Pin 0 to turn off the LED */
        ctrl &= ~E1000_CTRL_SWDPIN0;
        ctrl |= E1000_CTRL_SWDPIO0;
        break;
    case em_82544:
        if(hw->media_type == em_media_type_fiber) {
            /* Clear SW Defineable Pin 0 to turn off the LED */
            ctrl &= ~E1000_CTRL_SWDPIN0;
            ctrl |= E1000_CTRL_SWDPIO0;
        } else {
            /* Set SW Defineable Pin 0 to turn off the LED */
            ctrl |= E1000_CTRL_SWDPIN0;
            ctrl |= E1000_CTRL_SWDPIO0;
        }
        break;
    default:
        if(hw->media_type == em_media_type_fiber) {
            /* Set SW Defineable Pin 0 to turn off the LED */
            ctrl |= E1000_CTRL_SWDPIN0;
            ctrl |= E1000_CTRL_SWDPIO0;
        } else if(hw->media_type == em_media_type_copper) {
            E1000_WRITE_REG(hw, LEDCTL, hw->ledctl_mode1);
            return E1000_SUCCESS;
        }
        break;
    }

    E1000_WRITE_REG(hw, CTRL, ctrl);

    return E1000_SUCCESS;
}

/******************************************************************************
 * Clears all hardware statistics counters.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
void
em_clear_hw_cntrs(struct em_hw *hw)
{
    volatile uint32_t temp;

    temp = E1000_READ_REG(hw, CRCERRS);
    temp = E1000_READ_REG(hw, SYMERRS);
    temp = E1000_READ_REG(hw, MPC);
    temp = E1000_READ_REG(hw, SCC);
    temp = E1000_READ_REG(hw, ECOL);
    temp = E1000_READ_REG(hw, MCC);
    temp = E1000_READ_REG(hw, LATECOL);
    temp = E1000_READ_REG(hw, COLC);
    temp = E1000_READ_REG(hw, DC);
    temp = E1000_READ_REG(hw, SEC);
    temp = E1000_READ_REG(hw, RLEC);
    temp = E1000_READ_REG(hw, XONRXC);
    temp = E1000_READ_REG(hw, XONTXC);
    temp = E1000_READ_REG(hw, XOFFRXC);
    temp = E1000_READ_REG(hw, XOFFTXC);
    temp = E1000_READ_REG(hw, FCRUC);
    temp = E1000_READ_REG(hw, PRC64);
    temp = E1000_READ_REG(hw, PRC127);
    temp = E1000_READ_REG(hw, PRC255);
    temp = E1000_READ_REG(hw, PRC511);
    temp = E1000_READ_REG(hw, PRC1023);
    temp = E1000_READ_REG(hw, PRC1522);
    temp = E1000_READ_REG(hw, GPRC);
    temp = E1000_READ_REG(hw, BPRC);
    temp = E1000_READ_REG(hw, MPRC);
    temp = E1000_READ_REG(hw, GPTC);
    temp = E1000_READ_REG(hw, GORCL);
    temp = E1000_READ_REG(hw, GORCH);
    temp = E1000_READ_REG(hw, GOTCL);
    temp = E1000_READ_REG(hw, GOTCH);
    temp = E1000_READ_REG(hw, RNBC);
    temp = E1000_READ_REG(hw, RUC);
    temp = E1000_READ_REG(hw, RFC);
    temp = E1000_READ_REG(hw, ROC);
    temp = E1000_READ_REG(hw, RJC);
    temp = E1000_READ_REG(hw, TORL);
    temp = E1000_READ_REG(hw, TORH);
    temp = E1000_READ_REG(hw, TOTL);
    temp = E1000_READ_REG(hw, TOTH);
    temp = E1000_READ_REG(hw, TPR);
    temp = E1000_READ_REG(hw, TPT);
    temp = E1000_READ_REG(hw, PTC64);
    temp = E1000_READ_REG(hw, PTC127);
    temp = E1000_READ_REG(hw, PTC255);
    temp = E1000_READ_REG(hw, PTC511);
    temp = E1000_READ_REG(hw, PTC1023);
    temp = E1000_READ_REG(hw, PTC1522);
    temp = E1000_READ_REG(hw, MPTC);
    temp = E1000_READ_REG(hw, BPTC);

    if(hw->mac_type < em_82543) return;

    temp = E1000_READ_REG(hw, ALGNERRC);
    temp = E1000_READ_REG(hw, RXERRC);
    temp = E1000_READ_REG(hw, TNCRS);
    temp = E1000_READ_REG(hw, CEXTERR);
    temp = E1000_READ_REG(hw, TSCTC);
    temp = E1000_READ_REG(hw, TSCTFC);

    if(hw->mac_type <= em_82544) return;

    temp = E1000_READ_REG(hw, MGTPRC);
    temp = E1000_READ_REG(hw, MGTPDC);
    temp = E1000_READ_REG(hw, MGTPTC);
}

/******************************************************************************
 * Resets Adaptive IFS to its default state.
 *
 * hw - Struct containing variables accessed by shared code
 *
 * Call this after em_init_hw. You may override the IFS defaults by setting
 * hw->ifs_params_forced to TRUE. However, you must initialize hw->
 * current_ifs_val, ifs_min_val, ifs_max_val, ifs_step_size, and ifs_ratio
 * before calling this function.
 *****************************************************************************/
void
em_reset_adaptive(struct em_hw *hw)
{
    DEBUGFUNC("em_reset_adaptive");

    if(hw->adaptive_ifs) {
        if(!hw->ifs_params_forced) {
            hw->current_ifs_val = 0;
            hw->ifs_min_val = IFS_MIN;
            hw->ifs_max_val = IFS_MAX;
            hw->ifs_step_size = IFS_STEP;
            hw->ifs_ratio = IFS_RATIO;
        }
        hw->in_ifs_mode = FALSE;
        E1000_WRITE_REG(hw, AIT, 0);
    } else {
        DEBUGOUT("Not in Adaptive IFS mode!\n");
    }
}

/******************************************************************************
 * Called during the callback/watchdog routine to update IFS value based on
 * the ratio of transmits to collisions.
 *
 * hw - Struct containing variables accessed by shared code
 * tx_packets - Number of transmits since last callback
 * total_collisions - Number of collisions since last callback
 *****************************************************************************/
void
em_update_adaptive(struct em_hw *hw)
{
    DEBUGFUNC("em_update_adaptive");

    if(hw->adaptive_ifs) {
        if((hw->collision_delta * hw->ifs_ratio) > hw->tx_packet_delta) {
            if(hw->tx_packet_delta > MIN_NUM_XMITS) {
                hw->in_ifs_mode = TRUE;
                if(hw->current_ifs_val < hw->ifs_max_val) {
                    if(hw->current_ifs_val == 0)
                        hw->current_ifs_val = hw->ifs_min_val;
                    else
                        hw->current_ifs_val += hw->ifs_step_size;
                    E1000_WRITE_REG(hw, AIT, hw->current_ifs_val);
                }
            }
        } else {
            if(hw->in_ifs_mode && (hw->tx_packet_delta <= MIN_NUM_XMITS)) {
                hw->current_ifs_val = 0;
                hw->in_ifs_mode = FALSE;
                E1000_WRITE_REG(hw, AIT, 0);
            }
        }
    } else {
        DEBUGOUT("Not in Adaptive IFS mode!\n");
    }
}

/******************************************************************************
 * Adjusts the statistic counters when a frame is accepted by TBI_ACCEPT
 *
 * hw - Struct containing variables accessed by shared code
 * frame_len - The length of the frame in question
 * mac_addr - The Ethernet destination address of the frame in question
 *****************************************************************************/
void
em_tbi_adjust_stats(struct em_hw *hw,
                       struct em_hw_stats *stats,
                       uint32_t frame_len,
                       uint8_t *mac_addr)
{
    uint64_t 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((mac_addr[0] == (uint8_t) 0xff) && (mac_addr[1] == (uint8_t) 0xff))
        /* Broadcast packet */
        stats->bprc++;
    else if(*mac_addr & 0x01)
        /* Multicast packet */
        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++;
    }
}

/******************************************************************************
 * Gets the current PCI bus type, speed, and width of the hardware
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
void
em_get_bus_info(struct em_hw *hw)
{
    uint32_t status;

    if(hw->mac_type < em_82543) {
        hw->bus_type = em_bus_type_unknown;
        hw->bus_speed = em_bus_speed_unknown;
        hw->bus_width = em_bus_width_unknown;
        return;
    }

    status = E1000_READ_REG(hw, STATUS);
    hw->bus_type = (status & E1000_STATUS_PCIX_MODE) ?
                   em_bus_type_pcix : em_bus_type_pci;

    if(hw->device_id == E1000_DEV_ID_82546EB_QUAD_COPPER) {
        hw->bus_speed = (hw->bus_type == em_bus_type_pci) ?
                        em_bus_speed_66 : em_bus_speed_120;
    } else if(hw->bus_type == em_bus_type_pci) {
        hw->bus_speed = (status & E1000_STATUS_PCI66) ?
                        em_bus_speed_66 : em_bus_speed_33;
    } else {
        switch (status & E1000_STATUS_PCIX_SPEED) {
        case E1000_STATUS_PCIX_SPEED_66:
            hw->bus_speed = em_bus_speed_66;
            break;
        case E1000_STATUS_PCIX_SPEED_100:
            hw->bus_speed = em_bus_speed_100;
            break;
        case E1000_STATUS_PCIX_SPEED_133:
            hw->bus_speed = em_bus_speed_133;
            break;
        default:
            hw->bus_speed = em_bus_speed_reserved;
            break;
        }
    }
    hw->bus_width = (status & E1000_STATUS_BUS64) ?
                    em_bus_width_64 : em_bus_width_32;
}
/******************************************************************************
 * Reads a value from one of the devices registers using port I/O (as opposed
 * memory mapped I/O). Only 82544 and newer devices support port I/O.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - offset to read from
 *****************************************************************************/
uint32_t
em_read_reg_io(struct em_hw *hw,
                  uint32_t offset)
{
    uint32_t io_addr = hw->io_base;
    uint32_t io_data = hw->io_base + 4;

    em_io_write(hw, io_addr, offset);
    return em_io_read(hw, io_data);
}

/******************************************************************************
 * Writes a value to one of the devices registers using port I/O (as opposed to
 * memory mapped I/O). Only 82544 and newer devices support port I/O.
 *
 * hw - Struct containing variables accessed by shared code
 * offset - offset to write to
 * value - value to write
 *****************************************************************************/
void
em_write_reg_io(struct em_hw *hw,
                   uint32_t offset,
                   uint32_t value)
{
    uint32_t io_addr = hw->io_base;
    uint32_t io_data = hw->io_base + 4;

    em_io_write(hw, io_addr, offset);
    em_io_write(hw, io_data, value);
}


/******************************************************************************
 * Estimates the cable length.
 *
 * hw - Struct containing variables accessed by shared code
 * min_length - The estimated minimum length
 * max_length - The estimated maximum length
 *
 * returns: - E1000_ERR_XXX
 *            E1000_SUCCESS
 *
 * This function always returns a ranged length (minimum & maximum).
 * So for M88 phy's, this function interprets the one value returned from the
 * register to the minimum and maximum range.
 * For IGP phy's, the function calculates the range by the AGC registers.
 *****************************************************************************/
int32_t
em_get_cable_length(struct em_hw *hw,
                       uint16_t *min_length,
                       uint16_t *max_length)
{
    int32_t ret_val;
    uint16_t agc_value = 0;
    uint16_t cur_agc, min_agc = IGP01E1000_AGC_LENGTH_TABLE_SIZE;
    uint16_t i, phy_data;

    DEBUGFUNC("em_get_cable_length");

    *min_length = *max_length = 0;

    /* Use old method for Phy older than IGP */
    if(hw->phy_type == em_phy_m88) {
        if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_STATUS,
                                         &phy_data)))
            return ret_val;

        /* Convert the enum value to ranged values */
        switch((phy_data & M88E1000_PSSR_CABLE_LENGTH) >>
               M88E1000_PSSR_CABLE_LENGTH_SHIFT) {
        case em_cable_length_50:
            *min_length = 0;
            *max_length = em_igp_cable_length_50;
            break;
        case em_cable_length_50_80:
            *min_length = em_igp_cable_length_50;
            *max_length = em_igp_cable_length_80;
            break;
        case em_cable_length_80_110:
            *min_length = em_igp_cable_length_80;
            *max_length = em_igp_cable_length_110;
            break;
        case em_cable_length_110_140:
            *min_length = em_igp_cable_length_110;
            *max_length = em_igp_cable_length_140;
            break;
        case em_cable_length_140:
            *min_length = em_igp_cable_length_140;
            *max_length = em_igp_cable_length_170;
            break;
        default:
            return -E1000_ERR_PHY;
            break;
        }
    } else if(hw->phy_type == em_phy_igp) { /* For IGP PHY */
        uint16_t agc_reg_array[IGP01E1000_PHY_CHANNEL_NUM] =
                                                         {IGP01E1000_PHY_AGC_A,
                                                          IGP01E1000_PHY_AGC_B,
                                                          IGP01E1000_PHY_AGC_C,
                                                          IGP01E1000_PHY_AGC_D};
        /* Read the AGC registers for all channels */
        for(i = 0; i < IGP01E1000_PHY_CHANNEL_NUM; i++) {

            if((ret_val = em_read_phy_reg(hw, agc_reg_array[i], &phy_data)))
                return ret_val;

            cur_agc = phy_data >> IGP01E1000_AGC_LENGTH_SHIFT;

            /* Array bound check. */
            if((cur_agc >= IGP01E1000_AGC_LENGTH_TABLE_SIZE - 1) ||
               (cur_agc == 0))
                return -E1000_ERR_PHY;

            agc_value += cur_agc;

            /* Update minimal AGC value. */
            if(min_agc > cur_agc)
                min_agc = cur_agc;
        }

        /* Remove the minimal AGC result for length < 50m */
        if(agc_value < IGP01E1000_PHY_CHANNEL_NUM * em_igp_cable_length_50) {
            agc_value -= min_agc;

            /* Get the average length of the remaining 3 channels */
            agc_value /= (IGP01E1000_PHY_CHANNEL_NUM - 1);
        } else {
            /* Get the average length of all the 4 channels. */
            agc_value /= IGP01E1000_PHY_CHANNEL_NUM;
        }

        /* Set the range of the calculated length. */
        *min_length = ((em_igp_cable_length_table[agc_value] -
                       IGP01E1000_AGC_RANGE) > 0) ?
                       (em_igp_cable_length_table[agc_value] -
                       IGP01E1000_AGC_RANGE) : 0;
        *max_length = em_igp_cable_length_table[agc_value] +
                      IGP01E1000_AGC_RANGE;
    }

    return E1000_SUCCESS;
}

/******************************************************************************
 * Check the cable polarity
 *
 * hw - Struct containing variables accessed by shared code
 * polarity - output parameter : 0 - Polarity is not reversed
 *                               1 - Polarity is reversed.
 *
 * returns: - E1000_ERR_XXX
 *            E1000_SUCCESS
 *
 * For phy's older then IGP, this function simply reads the polarity bit in the
 * Phy Status register.  For IGP phy's, this bit is valid only if link speed is
 * 10 Mbps.  If the link speed is 100 Mbps there is no polarity so this bit will
 * return 0.  If the link speed is 1000 Mbps the polarity status is in the
 * IGP01E1000_PHY_PCS_INIT_REG.
 *****************************************************************************/
int32_t
em_check_polarity(struct em_hw *hw,
                     uint16_t *polarity)
{
    int32_t ret_val;
    uint16_t phy_data;

    DEBUGFUNC("em_check_polarity");

    if(hw->phy_type == em_phy_m88) {
        /* return the Polarity bit in the Status register. */
        if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_STATUS,
                                         &phy_data)))
            return ret_val;
        *polarity = (phy_data & M88E1000_PSSR_REV_POLARITY) >>
                    M88E1000_PSSR_REV_POLARITY_SHIFT;
    } else if(hw->phy_type == em_phy_igp) {
        /* Read the Status register to check the speed */
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_STATUS,
                                         &phy_data)))
            return ret_val;

        /* If speed is 1000 Mbps, must read the IGP01E1000_PHY_PCS_INIT_REG to
         * find the polarity status */
        if((phy_data & IGP01E1000_PSSR_SPEED_MASK) ==
           IGP01E1000_PSSR_SPEED_1000MBPS) {

            /* Read the GIG initialization PCS register (0x00B4) */
            if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PCS_INIT_REG,
                                             &phy_data)))
                return ret_val;

            /* Check the polarity bits */
            *polarity = (phy_data & IGP01E1000_PHY_POLARITY_MASK) ? 1 : 0;
        } else {
            /* For 10 Mbps, read the polarity bit in the status register. (for
             * 100 Mbps this bit is always 0) */
            *polarity = phy_data & IGP01E1000_PSSR_POLARITY_REVERSED;
        }
    }
    return E1000_SUCCESS;
}

/******************************************************************************
 * Check if Downshift occured
 *
 * hw - Struct containing variables accessed by shared code
 * downshift - output parameter : 0 - No Downshift ocured.
 *                                1 - Downshift ocured.
 *
 * returns: - E1000_ERR_XXX
 *            E1000_SUCCESS 
 *
 * For phy's older then IGP, this function reads the Downshift bit in the Phy
 * Specific Status register.  For IGP phy's, it reads the Downgrade bit in the
 * Link Health register.  In IGP this bit is latched high, so the driver must
 * read it immediately after link is established.
 *****************************************************************************/
int32_t
em_check_downshift(struct em_hw *hw)
{
    int32_t ret_val;
    uint16_t phy_data;

    DEBUGFUNC("em_check_downshift");

    if(hw->phy_type == em_phy_igp) {
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_LINK_HEALTH,
                                         &phy_data)))
            return ret_val;

        hw->speed_downgraded = (phy_data & IGP01E1000_PLHR_SS_DOWNGRADE) ? 1 : 0;
    }
    else if(hw->phy_type == em_phy_m88) {
        if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_SPEC_STATUS,
                                         &phy_data)))
            return ret_val;

        hw->speed_downgraded = (phy_data & M88E1000_PSSR_DOWNSHIFT) >>
                               M88E1000_PSSR_DOWNSHIFT_SHIFT;
    }
    return E1000_SUCCESS;
}

/*****************************************************************************
 *
 * 82541_rev_2 & 82547_rev_2 have the capability to configure the DSP when a
 * gigabit link is achieved to improve link quality.
 *
 * hw: Struct containing variables accessed by shared code
 *
 * returns: - E1000_ERR_PHY if fail to read/write the PHY
 *            E1000_SUCCESS at any other case.
 *
 ****************************************************************************/

int32_t
em_config_dsp_after_link_change(struct em_hw *hw,
                                   boolean_t link_up)
{
    int32_t ret_val;
    uint16_t phy_data, speed, duplex, i;
    uint16_t dsp_reg_array[IGP01E1000_PHY_CHANNEL_NUM] =
                                        {IGP01E1000_PHY_AGC_PARAM_A,
                                        IGP01E1000_PHY_AGC_PARAM_B,
                                        IGP01E1000_PHY_AGC_PARAM_C,
                                        IGP01E1000_PHY_AGC_PARAM_D};
    uint16_t min_length, max_length;

    DEBUGFUNC("em_config_dsp_after_link_change");

    if(hw->phy_type != em_phy_igp)
        return E1000_SUCCESS;

    if(link_up) {
        if((ret_val = em_get_speed_and_duplex(hw, &speed, &duplex))) {
            DEBUGOUT("Error getting link speed and duplex\n");
            return ret_val;
        }

        if(speed == SPEED_1000) {

            em_get_cable_length(hw, &min_length, &max_length);

            if((hw->dsp_config_state == em_dsp_config_enabled) &&
                min_length >= em_igp_cable_length_50) {

                for(i = 0; i < IGP01E1000_PHY_CHANNEL_NUM; i++) {
                    if((ret_val = em_read_phy_reg(hw, dsp_reg_array[i],
                                                     &phy_data)))
                        return ret_val;

                    phy_data &= ~IGP01E1000_PHY_EDAC_MU_INDEX;

                    if((ret_val = em_write_phy_reg(hw, dsp_reg_array[i],
                                                      phy_data)))
                        return ret_val;
                }
                hw->dsp_config_state = em_dsp_config_activated;
            }

            if((hw->ffe_config_state == em_ffe_config_enabled) &&
               (min_length < em_igp_cable_length_50)) {

                uint16_t ffe_idle_err_timeout = FFE_IDLE_ERR_COUNT_TIMEOUT_20;
                uint32_t idle_errs = 0;

                /* clear previous idle error counts */
                if((ret_val = em_read_phy_reg(hw, PHY_1000T_STATUS,
                                                 &phy_data)))
                    return ret_val;

                for(i = 0; i < ffe_idle_err_timeout; i++) {
                    usec_delay(1000);
                    if((ret_val = em_read_phy_reg(hw, PHY_1000T_STATUS,
                                                     &phy_data)))
                        return ret_val;

                    idle_errs += (phy_data & SR_1000T_IDLE_ERROR_CNT);
                    if(idle_errs > SR_1000T_PHY_EXCESSIVE_IDLE_ERR_COUNT) {
                        hw->ffe_config_state = em_ffe_config_active;

                        if((ret_val = em_write_phy_reg(hw,
                                    IGP01E1000_PHY_DSP_FFE,
                                    IGP01E1000_PHY_DSP_FFE_CM_CP)))
                            return ret_val;
                        break;
                    }

                    if(idle_errs)
                        ffe_idle_err_timeout = FFE_IDLE_ERR_COUNT_TIMEOUT_100;
                }
            }
        }
    } else {
        if(hw->dsp_config_state == em_dsp_config_activated) {
            if((ret_val = em_write_phy_reg(hw, 0x0000,
                IGP01E1000_IEEE_FORCE_GIGA)))
                return ret_val;
            for(i = 0; i < IGP01E1000_PHY_CHANNEL_NUM; i++) {
                if((ret_val = em_read_phy_reg(hw, dsp_reg_array[i],
                                                 &phy_data)))
                    return ret_val;

                phy_data &= ~IGP01E1000_PHY_EDAC_MU_INDEX;
                phy_data |=  IGP01E1000_PHY_EDAC_SIGN_EXT_9_BITS;

                if((ret_val = em_write_phy_reg(hw,dsp_reg_array[i],
                                                  phy_data)))
                    return ret_val;
            }

            if((ret_val = em_write_phy_reg(hw, 0x0000,
                                              IGP01E1000_IEEE_RESTART_AUTONEG)))
                return ret_val;

            hw->dsp_config_state = em_dsp_config_enabled;
        }

        if(hw->ffe_config_state == em_ffe_config_active) {
            if((ret_val = em_write_phy_reg(hw, 0x0000,
                                              IGP01E1000_IEEE_FORCE_GIGA)))
                return ret_val;
            if((ret_val = em_write_phy_reg(hw, IGP01E1000_PHY_DSP_FFE,
                                              IGP01E1000_PHY_DSP_FFE_DEFAULT)))
                return ret_val;

            if((ret_val = em_write_phy_reg(hw, 0x0000,
                                              IGP01E1000_IEEE_RESTART_AUTONEG)))
                return ret_val;
        hw->ffe_config_state = em_ffe_config_enabled;
        }
    }
    return E1000_SUCCESS;
}

/*****************************************************************************
 *
 * This function sets the lplu state according to the active flag.  When
 * activating lplu this function also disables smart speed and vise versa.
 * lplu will not be activated unless the device autonegotiation advertisment
 * meets standards of either 10 or 10/100 or 10/100/1000 at all duplexes.
 * hw: Struct containing variables accessed by shared code
 * active - true to enable lplu false to disable lplu.
 *
 * returns: - E1000_ERR_PHY if fail to read/write the PHY
 *            E1000_SUCCESS at any other case.
 *
 ****************************************************************************/

int32_t
em_set_d3_lplu_state(struct em_hw *hw,
                        boolean_t active)
{
    int32_t ret_val;
    uint16_t phy_data;
    DEBUGFUNC("em_set_d3_lplu_state");

    if(!((hw->mac_type == em_82541_rev_2) ||
         (hw->mac_type == em_82547_rev_2)))
        return E1000_SUCCESS;

    /* During driver activity LPLU should not be used or it will attain link
     * from the lowest speeds starting from 10Mbps. The capability is used for
     * Dx transitions and states */
    if((ret_val = em_read_phy_reg(hw, IGP01E1000_GMII_FIFO, &phy_data)))
        return ret_val;

    if(!active) {
        phy_data &= ~IGP01E1000_GMII_FLEX_SPD;
        if((ret_val = em_write_phy_reg(hw, IGP01E1000_GMII_FIFO, phy_data)))
            return ret_val;

        /* LPLU and SmartSpeed are mutually exclusive.  LPLU is used during
         * Dx states where the power conservation is most important.  During
         * driver activity we should enable SmartSpeed, so performance is
         * maintained. */
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_CONFIG,
                                         &phy_data)))
            return ret_val;

        phy_data |= IGP01E1000_PSCFR_SMART_SPEED;
        if((ret_val = em_write_phy_reg(hw, IGP01E1000_PHY_PORT_CONFIG,
                                          phy_data)))
            return ret_val;

    } else if((hw->autoneg_advertised == AUTONEG_ADVERTISE_SPEED_DEFAULT) ||
              (hw->autoneg_advertised == AUTONEG_ADVERTISE_10_ALL ) ||
              (hw->autoneg_advertised == AUTONEG_ADVERTISE_10_100_ALL)) {

        phy_data |= IGP01E1000_GMII_FLEX_SPD;
        if((ret_val = em_write_phy_reg(hw, IGP01E1000_GMII_FIFO, phy_data)))
            return ret_val;

        /* When LPLU is enabled we should disable SmartSpeed */
        if((ret_val = em_read_phy_reg(hw, IGP01E1000_PHY_PORT_CONFIG,
                                         &phy_data)))
            return ret_val;

        phy_data &= ~IGP01E1000_PSCFR_SMART_SPEED;
        if((ret_val = em_write_phy_reg(hw, IGP01E1000_PHY_PORT_CONFIG,
                                          phy_data)))
            return ret_val;

    }
    return E1000_SUCCESS;
}

/******************************************************************************
 * Change VCO speed register to improve Bit Error Rate performance of SERDES.
 *
 * hw - Struct containing variables accessed by shared code
 *****************************************************************************/
static int32_t
em_set_vco_speed(struct em_hw *hw)
{
    int32_t  ret_val;
    uint16_t default_page = 0;
    uint16_t phy_data;

    DEBUGFUNC("em_set_vco_speed");

    switch(hw->mac_type) {
    case em_82545_rev_3:
    case em_82546_rev_3:
       break;
    default:
        return E1000_SUCCESS;
    }

    /* Set PHY register 30, page 5, bit 8 to 0 */

    if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_PAGE_SELECT,
                                     &default_page)))
        return ret_val;

    if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_PAGE_SELECT, 0x0005)))
        return ret_val;

    if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_GEN_CONTROL, &phy_data)))
        return ret_val;

    phy_data &= ~M88E1000_PHY_VCO_REG_BIT8;
    if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_GEN_CONTROL, phy_data)))
        return ret_val;

    /* Set PHY register 30, page 4, bit 11 to 1 */

    if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_PAGE_SELECT, 0x0004)))
        return ret_val;

    if((ret_val = em_read_phy_reg(hw, M88E1000_PHY_GEN_CONTROL, &phy_data)))
        return ret_val;

    phy_data |= M88E1000_PHY_VCO_REG_BIT11;
    if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_GEN_CONTROL, phy_data)))
        return ret_val;

    if((ret_val = em_write_phy_reg(hw, M88E1000_PHY_PAGE_SELECT,
                                      default_page)))
        return ret_val;

    return E1000_SUCCESS;
}