Linux-libre 4.10.3-gnu

[librecmc/linux-libre.git] / drivers / net / ethernet / intel / igb / e1000_mac.c

/* Intel(R) Gigabit Ethernet Linux driver
 * Copyright(c) 2007-2014 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, see <http://www.gnu.org/licenses/>.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Contact Information:
 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 */

#include <linux/if_ether.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>

#include "e1000_mac.h"

#include "igb.h"

static s32 igb_set_default_fc(struct e1000_hw *hw);
static s32 igb_set_fc_watermarks(struct e1000_hw *hw);

/**
 *  igb_get_bus_info_pcie - Get PCIe bus information
 *  @hw: pointer to the HW structure
 *
 *  Determines and stores the system bus information for a particular
 *  network interface.  The following bus information is determined and stored:
 *  bus speed, bus width, type (PCIe), and PCIe function.
 **/
s32 igb_get_bus_info_pcie(struct e1000_hw *hw)
{
        struct e1000_bus_info *bus = &hw->bus;
        s32 ret_val;
        u32 reg;
        u16 pcie_link_status;

        bus->type = e1000_bus_type_pci_express;

        ret_val = igb_read_pcie_cap_reg(hw,
                                        PCI_EXP_LNKSTA,
                                        &pcie_link_status);
        if (ret_val) {
                bus->width = e1000_bus_width_unknown;
                bus->speed = e1000_bus_speed_unknown;
        } else {
                switch (pcie_link_status & PCI_EXP_LNKSTA_CLS) {
                case PCI_EXP_LNKSTA_CLS_2_5GB:
                        bus->speed = e1000_bus_speed_2500;
                        break;
                case PCI_EXP_LNKSTA_CLS_5_0GB:
                        bus->speed = e1000_bus_speed_5000;
                        break;
                default:
                        bus->speed = e1000_bus_speed_unknown;
                        break;
                }

                bus->width = (enum e1000_bus_width)((pcie_link_status &
                                                     PCI_EXP_LNKSTA_NLW) >>
                                                     PCI_EXP_LNKSTA_NLW_SHIFT);
        }

        reg = rd32(E1000_STATUS);
        bus->func = (reg & E1000_STATUS_FUNC_MASK) >> E1000_STATUS_FUNC_SHIFT;

        return 0;
}

/**
 *  igb_clear_vfta - Clear VLAN filter table
 *  @hw: pointer to the HW structure
 *
 *  Clears the register array which contains the VLAN filter table by
 *  setting all the values to 0.
 **/
void igb_clear_vfta(struct e1000_hw *hw)
{
        u32 offset;

        for (offset = E1000_VLAN_FILTER_TBL_SIZE; offset--;)
                hw->mac.ops.write_vfta(hw, offset, 0);
}

/**
 *  igb_write_vfta - Write value to VLAN filter table
 *  @hw: pointer to the HW structure
 *  @offset: register offset in VLAN filter table
 *  @value: register value written to VLAN filter table
 *
 *  Writes value at the given offset in the register array which stores
 *  the VLAN filter table.
 **/
void igb_write_vfta(struct e1000_hw *hw, u32 offset, u32 value)
{
        struct igb_adapter *adapter = hw->back;

        array_wr32(E1000_VFTA, offset, value);
        wrfl();

        adapter->shadow_vfta[offset] = value;
}

/**
 *  igb_init_rx_addrs - Initialize receive address's
 *  @hw: pointer to the HW structure
 *  @rar_count: receive address registers
 *
 *  Setups the receive address registers by setting the base receive address
 *  register to the devices MAC address and clearing all the other receive
 *  address registers to 0.
 **/
void igb_init_rx_addrs(struct e1000_hw *hw, u16 rar_count)
{
        u32 i;
        u8 mac_addr[ETH_ALEN] = {0};

        /* Setup the receive address */
        hw_dbg("Programming MAC Address into RAR[0]\n");

        hw->mac.ops.rar_set(hw, hw->mac.addr, 0);

        /* Zero out the other (rar_entry_count - 1) receive addresses */
        hw_dbg("Clearing RAR[1-%u]\n", rar_count-1);
        for (i = 1; i < rar_count; i++)
                hw->mac.ops.rar_set(hw, mac_addr, i);
}

/**
 *  igb_find_vlvf_slot - find the VLAN id or the first empty slot
 *  @hw: pointer to hardware structure
 *  @vlan: VLAN id to write to VLAN filter
 *  @vlvf_bypass: skip VLVF if no match is found
 *
 *  return the VLVF index where this VLAN id should be placed
 *
 **/
static s32 igb_find_vlvf_slot(struct e1000_hw *hw, u32 vlan, bool vlvf_bypass)
{
        s32 regindex, first_empty_slot;
        u32 bits;

        /* short cut the special case */
        if (vlan == 0)
                return 0;

        /* if vlvf_bypass is set we don't want to use an empty slot, we
         * will simply bypass the VLVF if there are no entries present in the
         * VLVF that contain our VLAN
         */
        first_empty_slot = vlvf_bypass ? -E1000_ERR_NO_SPACE : 0;

        /* Search for the VLAN id in the VLVF entries. Save off the first empty
         * slot found along the way.
         *
         * pre-decrement loop covering (IXGBE_VLVF_ENTRIES - 1) .. 1
         */
        for (regindex = E1000_VLVF_ARRAY_SIZE; --regindex > 0;) {
                bits = rd32(E1000_VLVF(regindex)) & E1000_VLVF_VLANID_MASK;
                if (bits == vlan)
                        return regindex;
                if (!first_empty_slot && !bits)
                        first_empty_slot = regindex;
        }

        return first_empty_slot ? : -E1000_ERR_NO_SPACE;
}

/**
 *  igb_vfta_set - enable or disable vlan in VLAN filter table
 *  @hw: pointer to the HW structure
 *  @vlan: VLAN id to add or remove
 *  @vind: VMDq output index that maps queue to VLAN id
 *  @vlan_on: if true add filter, if false remove
 *
 *  Sets or clears a bit in the VLAN filter table array based on VLAN id
 *  and if we are adding or removing the filter
 **/
s32 igb_vfta_set(struct e1000_hw *hw, u32 vlan, u32 vind,
                 bool vlan_on, bool vlvf_bypass)
{
        struct igb_adapter *adapter = hw->back;
        u32 regidx, vfta_delta, vfta, bits;
        s32 vlvf_index;

        if ((vlan > 4095) || (vind > 7))
                return -E1000_ERR_PARAM;

        /* this is a 2 part operation - first the VFTA, then the
         * VLVF and VLVFB if VT Mode is set
         * We don't write the VFTA until we know the VLVF part succeeded.
         */

        /* Part 1
         * The VFTA is a bitstring made up of 128 32-bit registers
         * that enable the particular VLAN id, much like the MTA:
         *    bits[11-5]: which register
         *    bits[4-0]:  which bit in the register
         */
        regidx = vlan / 32;
        vfta_delta = BIT(vlan % 32);
        vfta = adapter->shadow_vfta[regidx];

        /* vfta_delta represents the difference between the current value
         * of vfta and the value we want in the register.  Since the diff
         * is an XOR mask we can just update vfta using an XOR.
         */
        vfta_delta &= vlan_on ? ~vfta : vfta;
        vfta ^= vfta_delta;

        /* Part 2
         * If VT Mode is set
         *   Either vlan_on
         *     make sure the VLAN is in VLVF
         *     set the vind bit in the matching VLVFB
         *   Or !vlan_on
         *     clear the pool bit and possibly the vind
         */
        if (!adapter->vfs_allocated_count)
                goto vfta_update;

        vlvf_index = igb_find_vlvf_slot(hw, vlan, vlvf_bypass);
        if (vlvf_index < 0) {
                if (vlvf_bypass)
                        goto vfta_update;
                return vlvf_index;
        }

        bits = rd32(E1000_VLVF(vlvf_index));

        /* set the pool bit */
        bits |= BIT(E1000_VLVF_POOLSEL_SHIFT + vind);
        if (vlan_on)
                goto vlvf_update;

        /* clear the pool bit */
        bits ^= BIT(E1000_VLVF_POOLSEL_SHIFT + vind);

        if (!(bits & E1000_VLVF_POOLSEL_MASK)) {
                /* Clear VFTA first, then disable VLVF.  Otherwise
                 * we run the risk of stray packets leaking into
                 * the PF via the default pool
                 */
                if (vfta_delta)
                        hw->mac.ops.write_vfta(hw, regidx, vfta);

                /* disable VLVF and clear remaining bit from pool */
                wr32(E1000_VLVF(vlvf_index), 0);

                return 0;
        }

        /* If there are still bits set in the VLVFB registers
         * for the VLAN ID indicated we need to see if the
         * caller is requesting that we clear the VFTA entry bit.
         * If the caller has requested that we clear the VFTA
         * entry bit but there are still pools/VFs using this VLAN
         * ID entry then ignore the request.  We're not worried
         * about the case where we're turning the VFTA VLAN ID
         * entry bit on, only when requested to turn it off as
         * there may be multiple pools and/or VFs using the
         * VLAN ID entry.  In that case we cannot clear the
         * VFTA bit until all pools/VFs using that VLAN ID have also
         * been cleared.  This will be indicated by "bits" being
         * zero.
         */
        vfta_delta = 0;

vlvf_update:
        /* record pool change and enable VLAN ID if not already enabled */
        wr32(E1000_VLVF(vlvf_index), bits | vlan | E1000_VLVF_VLANID_ENABLE);

vfta_update:
        /* bit was set/cleared before we started */
        if (vfta_delta)
                hw->mac.ops.write_vfta(hw, regidx, vfta);

        return 0;
}

/**
 *  igb_check_alt_mac_addr - Check for alternate MAC addr
 *  @hw: pointer to the HW structure
 *
 *  Checks the nvm for an alternate MAC address.  An alternate MAC address
 *  can be setup by pre-boot software and must be treated like a permanent
 *  address and must override the actual permanent MAC address.  If an
 *  alternate MAC address is found it is saved in the hw struct and
 *  programmed into RAR0 and the function returns success, otherwise the
 *  function returns an error.
 **/
s32 igb_check_alt_mac_addr(struct e1000_hw *hw)
{
        u32 i;
        s32 ret_val = 0;
        u16 offset, nvm_alt_mac_addr_offset, nvm_data;
        u8 alt_mac_addr[ETH_ALEN];

        /* Alternate MAC address is handled by the option ROM for 82580
         * and newer. SW support not required.
         */
        if (hw->mac.type >= e1000_82580)
                goto out;

        ret_val = hw->nvm.ops.read(hw, NVM_ALT_MAC_ADDR_PTR, 1,
                                 &nvm_alt_mac_addr_offset);
        if (ret_val) {
                hw_dbg("NVM Read Error\n");
                goto out;
        }

        if ((nvm_alt_mac_addr_offset == 0xFFFF) ||
            (nvm_alt_mac_addr_offset == 0x0000))
                /* There is no Alternate MAC Address */
                goto out;

        if (hw->bus.func == E1000_FUNC_1)
                nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN1;
        if (hw->bus.func == E1000_FUNC_2)
                nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN2;

        if (hw->bus.func == E1000_FUNC_3)
                nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN3;
        for (i = 0; i < ETH_ALEN; i += 2) {
                offset = nvm_alt_mac_addr_offset + (i >> 1);
                ret_val = hw->nvm.ops.read(hw, offset, 1, &nvm_data);
                if (ret_val) {
                        hw_dbg("NVM Read Error\n");
                        goto out;
                }

                alt_mac_addr[i] = (u8)(nvm_data & 0xFF);
                alt_mac_addr[i + 1] = (u8)(nvm_data >> 8);
        }

        /* if multicast bit is set, the alternate address will not be used */
        if (is_multicast_ether_addr(alt_mac_addr)) {
                hw_dbg("Ignoring Alternate Mac Address with MC bit set\n");
                goto out;
        }

        /* We have a valid alternate MAC address, and we want to treat it the
         * same as the normal permanent MAC address stored by the HW into the
         * RAR. Do this by mapping this address into RAR0.
         */
        hw->mac.ops.rar_set(hw, alt_mac_addr, 0);

out:
        return ret_val;
}

/**
 *  igb_rar_set - Set receive address register
 *  @hw: pointer to the HW structure
 *  @addr: pointer to the receive address
 *  @index: receive address array register
 *
 *  Sets the receive address array register at index to the address passed
 *  in by addr.
 **/
void igb_rar_set(struct e1000_hw *hw, u8 *addr, u32 index)
{
        u32 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 = ((u32) addr[0] |
                   ((u32) addr[1] << 8) |
                    ((u32) addr[2] << 16) | ((u32) addr[3] << 24));

        rar_high = ((u32) addr[4] | ((u32) addr[5] << 8));

        /* If MAC address zero, no need to set the AV bit */
        if (rar_low || rar_high)
                rar_high |= E1000_RAH_AV;

        /* Some bridges will combine consecutive 32-bit writes into
         * a single burst write, which will malfunction on some parts.
         * The flushes avoid this.
         */
        wr32(E1000_RAL(index), rar_low);
        wrfl();
        wr32(E1000_RAH(index), rar_high);
        wrfl();
}

/**
 *  igb_mta_set - Set multicast filter table address
 *  @hw: pointer to the HW structure
 *  @hash_value: determines the MTA register and bit to set
 *
 *  The multicast table address is a register array of 32-bit registers.
 *  The hash_value is used to determine what register the bit is in, the
 *  current value is read, the new bit is OR'd in and the new value is
 *  written back into the register.
 **/
void igb_mta_set(struct e1000_hw *hw, u32 hash_value)
{
        u32 hash_bit, hash_reg, mta;

        /* The MTA is a register array of 32-bit registers. It is
         * treated like an array of (32*mta_reg_count) 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 (hw->mac.mta_reg_count - 1) serves as a
         * mask to bits 31:5 of the hash value which gives us the
         * register we're modifying.  The hash bit within that register
         * is determined by the lower 5 bits of the hash value.
         */
        hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
        hash_bit = hash_value & 0x1F;

        mta = array_rd32(E1000_MTA, hash_reg);

        mta |= BIT(hash_bit);

        array_wr32(E1000_MTA, hash_reg, mta);
        wrfl();
}

/**
 *  igb_hash_mc_addr - Generate a multicast hash value
 *  @hw: pointer to the HW structure
 *  @mc_addr: pointer to a multicast address
 *
 *  Generates a multicast address hash value which is used to determine
 *  the multicast filter table array address and new table value.  See
 *  igb_mta_set()
 **/
static u32 igb_hash_mc_addr(struct e1000_hw *hw, u8 *mc_addr)
{
        u32 hash_value, hash_mask;
        u8 bit_shift = 0;

        /* Register count multiplied by bits per register */
        hash_mask = (hw->mac.mta_reg_count * 32) - 1;

        /* For a mc_filter_type of 0, bit_shift is the number of left-shifts
         * where 0xFF would still fall within the hash mask.
         */
        while (hash_mask >> bit_shift != 0xFF)
                bit_shift++;

        /* The portion of the address that is used for the hash table
         * is determined by the mc_filter_type setting.
         * The algorithm is such that there is a total of 8 bits of shifting.
         * The bit_shift for a mc_filter_type of 0 represents the number of
         * left-shifts where the MSB of mc_addr[5] would still fall within
         * the hash_mask.  Case 0 does this exactly.  Since there are a total
         * of 8 bits of shifting, then mc_addr[4] will shift right the
         * remaining number of bits. Thus 8 - bit_shift.  The rest of the
         * cases are a variation of this algorithm...essentially raising the
         * number of bits to shift mc_addr[5] left, while still keeping the
         * 8-bit shifting total.
         *
         * For example, given the following Destination MAC Address and an
         * mta register count of 128 (thus a 4096-bit vector and 0xFFF mask),
         * we can see that the bit_shift for case 0 is 4.  These are the hash
         * values resulting from each mc_filter_type...
         * [0] [1] [2] [3] [4] [5]
         * 01  AA  00  12  34  56
         * LSB                 MSB
         *
         * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
         * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
         * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
         * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
         */
        switch (hw->mac.mc_filter_type) {
        default:
        case 0:
                break;
        case 1:
                bit_shift += 1;
                break;
        case 2:
                bit_shift += 2;
                break;
        case 3:
                bit_shift += 4;
                break;
        }

        hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
                                  (((u16) mc_addr[5]) << bit_shift)));

        return hash_value;
}

/**
 *  igb_update_mc_addr_list - Update Multicast addresses
 *  @hw: pointer to the HW structure
 *  @mc_addr_list: array of multicast addresses to program
 *  @mc_addr_count: number of multicast addresses to program
 *
 *  Updates entire Multicast Table Array.
 *  The caller must have a packed mc_addr_list of multicast addresses.
 **/
void igb_update_mc_addr_list(struct e1000_hw *hw,
                             u8 *mc_addr_list, u32 mc_addr_count)
{
        u32 hash_value, hash_bit, hash_reg;
        int i;

        /* clear mta_shadow */
        memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));

        /* update mta_shadow from mc_addr_list */
        for (i = 0; (u32) i < mc_addr_count; i++) {
                hash_value = igb_hash_mc_addr(hw, mc_addr_list);

                hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
                hash_bit = hash_value & 0x1F;

                hw->mac.mta_shadow[hash_reg] |= BIT(hash_bit);
                mc_addr_list += (ETH_ALEN);
        }

        /* replace the entire MTA table */
        for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
                array_wr32(E1000_MTA, i, hw->mac.mta_shadow[i]);
        wrfl();
}

/**
 *  igb_clear_hw_cntrs_base - Clear base hardware counters
 *  @hw: pointer to the HW structure
 *
 *  Clears the base hardware counters by reading the counter registers.
 **/
void igb_clear_hw_cntrs_base(struct e1000_hw *hw)
{
        rd32(E1000_CRCERRS);
        rd32(E1000_SYMERRS);
        rd32(E1000_MPC);
        rd32(E1000_SCC);
        rd32(E1000_ECOL);
        rd32(E1000_MCC);
        rd32(E1000_LATECOL);
        rd32(E1000_COLC);
        rd32(E1000_DC);
        rd32(E1000_SEC);
        rd32(E1000_RLEC);
        rd32(E1000_XONRXC);
        rd32(E1000_XONTXC);
        rd32(E1000_XOFFRXC);
        rd32(E1000_XOFFTXC);
        rd32(E1000_FCRUC);
        rd32(E1000_GPRC);
        rd32(E1000_BPRC);
        rd32(E1000_MPRC);
        rd32(E1000_GPTC);
        rd32(E1000_GORCL);
        rd32(E1000_GORCH);
        rd32(E1000_GOTCL);
        rd32(E1000_GOTCH);
        rd32(E1000_RNBC);
        rd32(E1000_RUC);
        rd32(E1000_RFC);
        rd32(E1000_ROC);
        rd32(E1000_RJC);
        rd32(E1000_TORL);
        rd32(E1000_TORH);
        rd32(E1000_TOTL);
        rd32(E1000_TOTH);
        rd32(E1000_TPR);
        rd32(E1000_TPT);
        rd32(E1000_MPTC);
        rd32(E1000_BPTC);
}

/**
 *  igb_check_for_copper_link - Check for link (Copper)
 *  @hw: pointer to the HW structure
 *
 *  Checks to see of the link status of the hardware has changed.  If a
 *  change in link status has been detected, then we read the PHY registers
 *  to get the current speed/duplex if link exists.
 **/
s32 igb_check_for_copper_link(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        s32 ret_val;
        bool link;

        /* 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 is set upon receiving a Link Status
         * Change or Rx Sequence Error interrupt.
         */
        if (!mac->get_link_status) {
                ret_val = 0;
                goto out;
        }

        /* 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.
         */
        ret_val = igb_phy_has_link(hw, 1, 0, &link);
        if (ret_val)
                goto out;

        if (!link)
                goto out; /* No link detected */

        mac->get_link_status = false;

        /* Check if there was DownShift, must be checked
         * immediately after link-up
         */
        igb_check_downshift(hw);

        /* If we are forcing speed/duplex, then we simply return since
         * we have already determined whether we have link or not.
         */
        if (!mac->autoneg) {
                ret_val = -E1000_ERR_CONFIG;
                goto out;
        }

        /* Auto-Neg is enabled.  Auto Speed Detection takes care
         * of MAC speed/duplex configuration.  So we only need to
         * configure Collision Distance in the MAC.
         */
        igb_config_collision_dist(hw);

        /* 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.
         */
        ret_val = igb_config_fc_after_link_up(hw);
        if (ret_val)
                hw_dbg("Error configuring flow control\n");

out:
        return ret_val;
}

/**
 *  igb_setup_link - Setup flow control and link settings
 *  @hw: pointer to the HW structure
 *
 *  Determines which flow control settings to use, then configures flow
 *  control.  Calls the appropriate media-specific link configuration
 *  function.  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.
 **/
s32 igb_setup_link(struct e1000_hw *hw)
{
        s32 ret_val = 0;

        /* In the case of the phy reset being blocked, we already have a link.
         * We do not need to set it up again.
         */
        if (igb_check_reset_block(hw))
                goto out;

        /* If requested flow control is set to default, set flow control
         * based on the EEPROM flow control settings.
         */
        if (hw->fc.requested_mode == e1000_fc_default) {
                ret_val = igb_set_default_fc(hw);
                if (ret_val)
                        goto out;
        }

        /* 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.
         */
        hw->fc.current_mode = hw->fc.requested_mode;

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

        /* Call the necessary media_type subroutine to configure the link. */
        ret_val = hw->mac.ops.setup_physical_interface(hw);
        if (ret_val)
                goto out;

        /* 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.
         */
        hw_dbg("Initializing the Flow Control address, type and timer regs\n");
        wr32(E1000_FCT, FLOW_CONTROL_TYPE);
        wr32(E1000_FCAH, FLOW_CONTROL_ADDRESS_HIGH);
        wr32(E1000_FCAL, FLOW_CONTROL_ADDRESS_LOW);

        wr32(E1000_FCTTV, hw->fc.pause_time);

        ret_val = igb_set_fc_watermarks(hw);

out:

        return ret_val;
}

/**
 *  igb_config_collision_dist - Configure collision distance
 *  @hw: pointer to the HW structure
 *
 *  Configures the collision distance to the default value and is used
 *  during link setup. Currently no func pointer exists and all
 *  implementations are handled in the generic version of this function.
 **/
void igb_config_collision_dist(struct e1000_hw *hw)
{
        u32 tctl;

        tctl = rd32(E1000_TCTL);

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

        wr32(E1000_TCTL, tctl);
        wrfl();
}

/**
 *  igb_set_fc_watermarks - Set flow control high/low watermarks
 *  @hw: pointer to the HW structure
 *
 *  Sets the flow control high/low threshold (watermark) registers.  If
 *  flow control XON frame transmission is enabled, then set XON frame
 *  tansmission as well.
 **/
static s32 igb_set_fc_watermarks(struct e1000_hw *hw)
{
        s32 ret_val = 0;
        u32 fcrtl = 0, fcrth = 0;

        /* 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 is not enabled, then these
         * registers will be set to 0.
         */
        if (hw->fc.current_mode & e1000_fc_tx_pause) {
                /* We need to set up the Receive Threshold high and low water
                 * marks as well as (optionally) enabling the transmission of
                 * XON frames.
                 */
                fcrtl = hw->fc.low_water;
                if (hw->fc.send_xon)
                        fcrtl |= E1000_FCRTL_XONE;

                fcrth = hw->fc.high_water;
        }
        wr32(E1000_FCRTL, fcrtl);
        wr32(E1000_FCRTH, fcrth);

        return ret_val;
}

/**
 *  igb_set_default_fc - Set flow control default values
 *  @hw: pointer to the HW structure
 *
 *  Read the EEPROM for the default values for flow control and store the
 *  values.
 **/
static s32 igb_set_default_fc(struct e1000_hw *hw)
{
        s32 ret_val = 0;
        u16 lan_offset;
        u16 nvm_data;

        /* 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 (hw->mac.type == e1000_i350) {
                lan_offset = NVM_82580_LAN_FUNC_OFFSET(hw->bus.func);
                ret_val = hw->nvm.ops.read(hw, NVM_INIT_CONTROL2_REG
                                           + lan_offset, 1, &nvm_data);
         } else {
                ret_val = hw->nvm.ops.read(hw, NVM_INIT_CONTROL2_REG,
                                           1, &nvm_data);
         }

        if (ret_val) {
                hw_dbg("NVM Read Error\n");
                goto out;
        }

        if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == 0)
                hw->fc.requested_mode = e1000_fc_none;
        else if ((nvm_data & NVM_WORD0F_PAUSE_MASK) ==
                 NVM_WORD0F_ASM_DIR)
                hw->fc.requested_mode = e1000_fc_tx_pause;
        else
                hw->fc.requested_mode = e1000_fc_full;

out:
        return ret_val;
}

/**
 *  igb_force_mac_fc - Force the MAC's flow control settings
 *  @hw: pointer to the HW structure
 *
 *  Force the MAC's flow control settings.  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.
 **/
s32 igb_force_mac_fc(struct e1000_hw *hw)
{
        u32 ctrl;
        s32 ret_val = 0;

        ctrl = rd32(E1000_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.current_mode" 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.
         */
        hw_dbg("hw->fc.current_mode = %u\n", hw->fc.current_mode);

        switch (hw->fc.current_mode) {
        case e1000_fc_none:
                ctrl &= (~(E1000_CTRL_TFCE | E1000_CTRL_RFCE));
                break;
        case e1000_fc_rx_pause:
                ctrl &= (~E1000_CTRL_TFCE);
                ctrl |= E1000_CTRL_RFCE;
                break;
        case e1000_fc_tx_pause:
                ctrl &= (~E1000_CTRL_RFCE);
                ctrl |= E1000_CTRL_TFCE;
                break;
        case e1000_fc_full:
                ctrl |= (E1000_CTRL_TFCE | E1000_CTRL_RFCE);
                break;
        default:
                hw_dbg("Flow control param set incorrectly\n");
                ret_val = -E1000_ERR_CONFIG;
                goto out;
        }

        wr32(E1000_CTRL, ctrl);

out:
        return ret_val;
}

/**
 *  igb_config_fc_after_link_up - Configures flow control after link
 *  @hw: pointer to the HW structure
 *
 *  Checks the status of auto-negotiation after link up to ensure that the
 *  speed and duplex were not forced.  If the link needed to be forced, then
 *  flow control needs to be forced also.  If auto-negotiation is enabled
 *  and did not fail, then we configure flow control based on our link
 *  partner.
 **/
s32 igb_config_fc_after_link_up(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        s32 ret_val = 0;
        u32 pcs_status_reg, pcs_adv_reg, pcs_lp_ability_reg, pcs_ctrl_reg;
        u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg;
        u16 speed, duplex;

        /* 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 (mac->autoneg_failed) {
                if (hw->phy.media_type == e1000_media_type_internal_serdes)
                        ret_val = igb_force_mac_fc(hw);
        } else {
                if (hw->phy.media_type == e1000_media_type_copper)
                        ret_val = igb_force_mac_fc(hw);
        }

        if (ret_val) {
                hw_dbg("Error forcing flow control settings\n");
                goto out;
        }

        /* 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->phy.media_type == e1000_media_type_copper) && mac->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.
                 */
                ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
                                                   &mii_status_reg);
                if (ret_val)
                        goto out;
                ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
                                                   &mii_status_reg);
                if (ret_val)
                        goto out;

                if (!(mii_status_reg & MII_SR_AUTONEG_COMPLETE)) {
                        hw_dbg("Copper PHY and Auto Neg has not completed.\n");
                        goto out;
                }

                /* 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.
                 */
                ret_val = hw->phy.ops.read_reg(hw, PHY_AUTONEG_ADV,
                                            &mii_nway_adv_reg);
                if (ret_val)
                        goto out;
                ret_val = hw->phy.ops.read_reg(hw, PHY_LP_ABILITY,
                                            &mii_nway_lp_ability_reg);
                if (ret_val)
                        goto out;

                /* 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    | e1000_fc_none
                 *   0   |    1    |   0   |   DC    | e1000_fc_none
                 *   0   |    1    |   1   |    0    | e1000_fc_none
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 *   1   |    0    |   0   |   DC    | e1000_fc_none
                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
                 *   1   |    1    |   0   |    0    | e1000_fc_none
                 *   1   |    1    |   0   |    1    | e1000_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    | E1000_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->fc.requested_mode == e1000_fc_full) {
                                hw->fc.current_mode = e1000_fc_full;
                                hw_dbg("Flow Control = FULL.\n");
                        } else {
                                hw->fc.current_mode = e1000_fc_rx_pause;
                                hw_dbg("Flow Control = RX PAUSE frames only.\n");
                        }
                }
                /* For receiving PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   0   |    1    |   1   |    1    | e1000_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.current_mode = e1000_fc_tx_pause;
                        hw_dbg("Flow Control = TX PAUSE frames only.\n");
                }
                /* For transmitting PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   1   |    1    |   0   |    1    | e1000_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.current_mode = e1000_fc_rx_pause;
                        hw_dbg("Flow Control = RX PAUSE frames only.\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->fc.requested_mode == e1000_fc_none) ||
                         (hw->fc.requested_mode == e1000_fc_tx_pause) ||
                         (hw->fc.strict_ieee)) {
                        hw->fc.current_mode = e1000_fc_none;
                        hw_dbg("Flow Control = NONE.\n");
                } else {
                        hw->fc.current_mode = e1000_fc_rx_pause;
                        hw_dbg("Flow Control = RX PAUSE frames only.\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.
                 */
                ret_val = hw->mac.ops.get_speed_and_duplex(hw, &speed, &duplex);
                if (ret_val) {
                        hw_dbg("Error getting link speed and duplex\n");
                        goto out;
                }

                if (duplex == HALF_DUPLEX)
                        hw->fc.current_mode = e1000_fc_none;

                /* Now we call a subroutine to actually force the MAC
                 * controller to use the correct flow control settings.
                 */
                ret_val = igb_force_mac_fc(hw);
                if (ret_val) {
                        hw_dbg("Error forcing flow control settings\n");
                        goto out;
                }
        }
        /* Check for the case where we have SerDes 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->phy.media_type == e1000_media_type_internal_serdes)
                && mac->autoneg) {
                /* Read the PCS_LSTS and check to see if AutoNeg
                 * has completed.
                 */
                pcs_status_reg = rd32(E1000_PCS_LSTAT);

                if (!(pcs_status_reg & E1000_PCS_LSTS_AN_COMPLETE)) {
                        hw_dbg("PCS Auto Neg has not completed.\n");
                        return ret_val;
                }

                /* The AutoNeg process has completed, so we now need to
                 * read both the Auto Negotiation Advertisement
                 * Register (PCS_ANADV) and the Auto_Negotiation Base
                 * Page Ability Register (PCS_LPAB) to determine how
                 * flow control was negotiated.
                 */
                pcs_adv_reg = rd32(E1000_PCS_ANADV);
                pcs_lp_ability_reg = rd32(E1000_PCS_LPAB);

                /* Two bits in the Auto Negotiation Advertisement Register
                 * (PCS_ANADV) and two bits in the Auto Negotiation Base
                 * Page Ability Register (PCS_LPAB) 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    | e1000_fc_none
                 *   0   |    1    |   0   |   DC    | e1000_fc_none
                 *   0   |    1    |   1   |    0    | e1000_fc_none
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 *   1   |    0    |   0   |   DC    | e1000_fc_none
                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
                 *   1   |    1    |   0   |    0    | e1000_fc_none
                 *   1   |    1    |   0   |    1    | e1000_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    | e1000_fc_full
                 *
                 */
                if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
                    (pcs_lp_ability_reg & E1000_TXCW_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->fc.requested_mode == e1000_fc_full) {
                                hw->fc.current_mode = e1000_fc_full;
                                hw_dbg("Flow Control = FULL.\n");
                        } else {
                                hw->fc.current_mode = e1000_fc_rx_pause;
                                hw_dbg("Flow Control = Rx PAUSE frames only.\n");
                        }
                }
                /* For receiving PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
                 */
                else if (!(pcs_adv_reg & E1000_TXCW_PAUSE) &&
                          (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
                          (pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
                          (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
                        hw->fc.current_mode = e1000_fc_tx_pause;
                        hw_dbg("Flow Control = Tx PAUSE frames only.\n");
                }
                /* For transmitting PAUSE frames ONLY.
                 *
                 *   LOCAL DEVICE  |   LINK PARTNER
                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
                 *-------|---------|-------|---------|--------------------
                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
                 */
                else if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
                         (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
                         !(pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
                         (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
                        hw->fc.current_mode = e1000_fc_rx_pause;
                        hw_dbg("Flow Control = Rx PAUSE frames only.\n");
                } else {
                        /* Per the IEEE spec, at this point flow control
                         * should be disabled.
                         */
                        hw->fc.current_mode = e1000_fc_none;
                        hw_dbg("Flow Control = NONE.\n");
                }

                /* Now we call a subroutine to actually force the MAC
                 * controller to use the correct flow control settings.
                 */
                pcs_ctrl_reg = rd32(E1000_PCS_LCTL);
                pcs_ctrl_reg |= E1000_PCS_LCTL_FORCE_FCTRL;
                wr32(E1000_PCS_LCTL, pcs_ctrl_reg);

                ret_val = igb_force_mac_fc(hw);
                if (ret_val) {
                        hw_dbg("Error forcing flow control settings\n");
                        return ret_val;
                }
        }

out:
        return ret_val;
}

/**
 *  igb_get_speed_and_duplex_copper - Retrieve current speed/duplex
 *  @hw: pointer to the HW structure
 *  @speed: stores the current speed
 *  @duplex: stores the current duplex
 *
 *  Read the status register for the current speed/duplex and store the current
 *  speed and duplex for copper connections.
 **/
s32 igb_get_speed_and_duplex_copper(struct e1000_hw *hw, u16 *speed,
                                      u16 *duplex)
{
        u32 status;

        status = rd32(E1000_STATUS);
        if (status & E1000_STATUS_SPEED_1000) {
                *speed = SPEED_1000;
                hw_dbg("1000 Mbs, ");
        } else if (status & E1000_STATUS_SPEED_100) {
                *speed = SPEED_100;
                hw_dbg("100 Mbs, ");
        } else {
                *speed = SPEED_10;
                hw_dbg("10 Mbs, ");
        }

        if (status & E1000_STATUS_FD) {
                *duplex = FULL_DUPLEX;
                hw_dbg("Full Duplex\n");
        } else {
                *duplex = HALF_DUPLEX;
                hw_dbg("Half Duplex\n");
        }

        return 0;
}

/**
 *  igb_get_hw_semaphore - Acquire hardware semaphore
 *  @hw: pointer to the HW structure
 *
 *  Acquire the HW semaphore to access the PHY or NVM
 **/
s32 igb_get_hw_semaphore(struct e1000_hw *hw)
{
        u32 swsm;
        s32 ret_val = 0;
        s32 timeout = hw->nvm.word_size + 1;
        s32 i = 0;

        /* Get the SW semaphore */
        while (i < timeout) {
                swsm = rd32(E1000_SWSM);
                if (!(swsm & E1000_SWSM_SMBI))
                        break;

                udelay(50);
                i++;
        }

        if (i == timeout) {
                hw_dbg("Driver can't access device - SMBI bit is set.\n");
                ret_val = -E1000_ERR_NVM;
                goto out;
        }

        /* Get the FW semaphore. */
        for (i = 0; i < timeout; i++) {
                swsm = rd32(E1000_SWSM);
                wr32(E1000_SWSM, swsm | E1000_SWSM_SWESMBI);

                /* Semaphore acquired if bit latched */
                if (rd32(E1000_SWSM) & E1000_SWSM_SWESMBI)
                        break;

                udelay(50);
        }

        if (i == timeout) {
                /* Release semaphores */
                igb_put_hw_semaphore(hw);
                hw_dbg("Driver can't access the NVM\n");
                ret_val = -E1000_ERR_NVM;
                goto out;
        }

out:
        return ret_val;
}

/**
 *  igb_put_hw_semaphore - Release hardware semaphore
 *  @hw: pointer to the HW structure
 *
 *  Release hardware semaphore used to access the PHY or NVM
 **/
void igb_put_hw_semaphore(struct e1000_hw *hw)
{
        u32 swsm;

        swsm = rd32(E1000_SWSM);

        swsm &= ~(E1000_SWSM_SMBI | E1000_SWSM_SWESMBI);

        wr32(E1000_SWSM, swsm);
}

/**
 *  igb_get_auto_rd_done - Check for auto read completion
 *  @hw: pointer to the HW structure
 *
 *  Check EEPROM for Auto Read done bit.
 **/
s32 igb_get_auto_rd_done(struct e1000_hw *hw)
{
        s32 i = 0;
        s32 ret_val = 0;


        while (i < AUTO_READ_DONE_TIMEOUT) {
                if (rd32(E1000_EECD) & E1000_EECD_AUTO_RD)
                        break;
                usleep_range(1000, 2000);
                i++;
        }

        if (i == AUTO_READ_DONE_TIMEOUT) {
                hw_dbg("Auto read by HW from NVM has not completed.\n");
                ret_val = -E1000_ERR_RESET;
                goto out;
        }

out:
        return ret_val;
}

/**
 *  igb_valid_led_default - Verify a valid default LED config
 *  @hw: pointer to the HW structure
 *  @data: pointer to the NVM (EEPROM)
 *
 *  Read the EEPROM for the current default LED configuration.  If the
 *  LED configuration is not valid, set to a valid LED configuration.
 **/
static s32 igb_valid_led_default(struct e1000_hw *hw, u16 *data)
{
        s32 ret_val;

        ret_val = hw->nvm.ops.read(hw, NVM_ID_LED_SETTINGS, 1, data);
        if (ret_val) {
                hw_dbg("NVM Read Error\n");
                goto out;
        }

        if (*data == ID_LED_RESERVED_0000 || *data == ID_LED_RESERVED_FFFF) {
                switch (hw->phy.media_type) {
                case e1000_media_type_internal_serdes:
                        *data = ID_LED_DEFAULT_82575_SERDES;
                        break;
                case e1000_media_type_copper:
                default:
                        *data = ID_LED_DEFAULT;
                        break;
                }
        }
out:
        return ret_val;
}

/**
 *  igb_id_led_init -
 *  @hw: pointer to the HW structure
 *
 **/
s32 igb_id_led_init(struct e1000_hw *hw)
{
        struct e1000_mac_info *mac = &hw->mac;
        s32 ret_val;
        const u32 ledctl_mask = 0x000000FF;
        const u32 ledctl_on = E1000_LEDCTL_MODE_LED_ON;
        const u32 ledctl_off = E1000_LEDCTL_MODE_LED_OFF;
        u16 data, i, temp;
        const u16 led_mask = 0x0F;

        /* i210 and i211 devices have different LED mechanism */
        if ((hw->mac.type == e1000_i210) ||
            (hw->mac.type == e1000_i211))
                ret_val = igb_valid_led_default_i210(hw, &data);
        else
                ret_val = igb_valid_led_default(hw, &data);

        if (ret_val)
                goto out;

        mac->ledctl_default = rd32(E1000_LEDCTL);
        mac->ledctl_mode1 = mac->ledctl_default;
        mac->ledctl_mode2 = mac->ledctl_default;

        for (i = 0; i < 4; i++) {
                temp = (data >> (i << 2)) & led_mask;
                switch (temp) {
                case ID_LED_ON1_DEF2:
                case ID_LED_ON1_ON2:
                case ID_LED_ON1_OFF2:
                        mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode1 |= ledctl_on << (i << 3);
                        break;
                case ID_LED_OFF1_DEF2:
                case ID_LED_OFF1_ON2:
                case ID_LED_OFF1_OFF2:
                        mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
                        mac->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:
                        mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode2 |= ledctl_on << (i << 3);
                        break;
                case ID_LED_DEF1_OFF2:
                case ID_LED_ON1_OFF2:
                case ID_LED_OFF1_OFF2:
                        mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
                        mac->ledctl_mode2 |= ledctl_off << (i << 3);
                        break;
                default:
                        /* Do nothing */
                        break;
                }
        }

out:
        return ret_val;
}

/**
 *  igb_cleanup_led - Set LED config to default operation
 *  @hw: pointer to the HW structure
 *
 *  Remove the current LED configuration and set the LED configuration
 *  to the default value, saved from the EEPROM.
 **/
s32 igb_cleanup_led(struct e1000_hw *hw)
{
        wr32(E1000_LEDCTL, hw->mac.ledctl_default);
        return 0;
}

/**
 *  igb_blink_led - Blink LED
 *  @hw: pointer to the HW structure
 *
 *  Blink the led's which are set to be on.
 **/
s32 igb_blink_led(struct e1000_hw *hw)
{
        u32 ledctl_blink = 0;
        u32 i;

        if (hw->phy.media_type == e1000_media_type_fiber) {
                /* always blink LED0 for PCI-E fiber */
                ledctl_blink = E1000_LEDCTL_LED0_BLINK |
                     (E1000_LEDCTL_MODE_LED_ON << E1000_LEDCTL_LED0_MODE_SHIFT);
        } else {
                /* Set the blink bit for each LED that's "on" (0x0E)
                 * (or "off" if inverted) in ledctl_mode2.  The blink
                 * logic in hardware only works when mode is set to "on"
                 * so it must be changed accordingly when the mode is
                 * "off" and inverted.
                 */
                ledctl_blink = hw->mac.ledctl_mode2;
                for (i = 0; i < 32; i += 8) {
                        u32 mode = (hw->mac.ledctl_mode2 >> i) &
                            E1000_LEDCTL_LED0_MODE_MASK;
                        u32 led_default = hw->mac.ledctl_default >> i;

                        if ((!(led_default & E1000_LEDCTL_LED0_IVRT) &&
                             (mode == E1000_LEDCTL_MODE_LED_ON)) ||
                            ((led_default & E1000_LEDCTL_LED0_IVRT) &&
                             (mode == E1000_LEDCTL_MODE_LED_OFF))) {
                                ledctl_blink &=
                                    ~(E1000_LEDCTL_LED0_MODE_MASK << i);
                                ledctl_blink |= (E1000_LEDCTL_LED0_BLINK |
                                                 E1000_LEDCTL_MODE_LED_ON) << i;
                        }
                }
        }

        wr32(E1000_LEDCTL, ledctl_blink);

        return 0;
}

/**
 *  igb_led_off - Turn LED off
 *  @hw: pointer to the HW structure
 *
 *  Turn LED off.
 **/
s32 igb_led_off(struct e1000_hw *hw)
{
        switch (hw->phy.media_type) {
        case e1000_media_type_copper:
                wr32(E1000_LEDCTL, hw->mac.ledctl_mode1);
                break;
        default:
                break;
        }

        return 0;
}

/**
 *  igb_disable_pcie_master - Disables PCI-express master access
 *  @hw: pointer to the HW structure
 *
 *  Returns 0 (0) if successful, else returns -10
 *  (-E1000_ERR_MASTER_REQUESTS_PENDING) if master disable bit has not caused
 *  the master requests to be disabled.
 *
 *  Disables PCI-Express master access and verifies there are no pending
 *  requests.
 **/
s32 igb_disable_pcie_master(struct e1000_hw *hw)
{
        u32 ctrl;
        s32 timeout = MASTER_DISABLE_TIMEOUT;
        s32 ret_val = 0;

        if (hw->bus.type != e1000_bus_type_pci_express)
                goto out;

        ctrl = rd32(E1000_CTRL);
        ctrl |= E1000_CTRL_GIO_MASTER_DISABLE;
        wr32(E1000_CTRL, ctrl);

        while (timeout) {
                if (!(rd32(E1000_STATUS) &
                      E1000_STATUS_GIO_MASTER_ENABLE))
                        break;
                udelay(100);
                timeout--;
        }

        if (!timeout) {
                hw_dbg("Master requests are pending.\n");
                ret_val = -E1000_ERR_MASTER_REQUESTS_PENDING;
                goto out;
        }

out:
        return ret_val;
}

/**
 *  igb_validate_mdi_setting - Verify MDI/MDIx settings
 *  @hw: pointer to the HW structure
 *
 *  Verify that when not using auto-negotitation that MDI/MDIx is correctly
 *  set, which is forced to MDI mode only.
 **/
s32 igb_validate_mdi_setting(struct e1000_hw *hw)
{
        s32 ret_val = 0;

        /* All MDI settings are supported on 82580 and newer. */
        if (hw->mac.type >= e1000_82580)
                goto out;

        if (!hw->mac.autoneg && (hw->phy.mdix == 0 || hw->phy.mdix == 3)) {
                hw_dbg("Invalid MDI setting detected\n");
                hw->phy.mdix = 1;
                ret_val = -E1000_ERR_CONFIG;
                goto out;
        }

out:
        return ret_val;
}

/**
 *  igb_write_8bit_ctrl_reg - Write a 8bit CTRL register
 *  @hw: pointer to the HW structure
 *  @reg: 32bit register offset such as E1000_SCTL
 *  @offset: register offset to write to
 *  @data: data to write at register offset
 *
 *  Writes an address/data control type register.  There are several of these
 *  and they all have the format address << 8 | data and bit 31 is polled for
 *  completion.
 **/
s32 igb_write_8bit_ctrl_reg(struct e1000_hw *hw, u32 reg,
                              u32 offset, u8 data)
{
        u32 i, regvalue = 0;
        s32 ret_val = 0;

        /* Set up the address and data */
        regvalue = ((u32)data) | (offset << E1000_GEN_CTL_ADDRESS_SHIFT);
        wr32(reg, regvalue);

        /* Poll the ready bit to see if the MDI read completed */
        for (i = 0; i < E1000_GEN_POLL_TIMEOUT; i++) {
                udelay(5);
                regvalue = rd32(reg);
                if (regvalue & E1000_GEN_CTL_READY)
                        break;
        }
        if (!(regvalue & E1000_GEN_CTL_READY)) {
                hw_dbg("Reg %08x did not indicate ready\n", reg);
                ret_val = -E1000_ERR_PHY;
                goto out;
        }

out:
        return ret_val;
}

/**
 *  igb_enable_mng_pass_thru - Enable processing of ARP's
 *  @hw: pointer to the HW structure
 *
 *  Verifies the hardware needs to leave interface enabled so that frames can
 *  be directed to and from the management interface.
 **/
bool igb_enable_mng_pass_thru(struct e1000_hw *hw)
{
        u32 manc;
        u32 fwsm, factps;
        bool ret_val = false;

        if (!hw->mac.asf_firmware_present)
                goto out;

        manc = rd32(E1000_MANC);

        if (!(manc & E1000_MANC_RCV_TCO_EN))
                goto out;

        if (hw->mac.arc_subsystem_valid) {
                fwsm = rd32(E1000_FWSM);
                factps = rd32(E1000_FACTPS);

                if (!(factps & E1000_FACTPS_MNGCG) &&
                    ((fwsm & E1000_FWSM_MODE_MASK) ==
                     (e1000_mng_mode_pt << E1000_FWSM_MODE_SHIFT))) {
                        ret_val = true;
                        goto out;
                }
        } else {
                if ((manc & E1000_MANC_SMBUS_EN) &&
                    !(manc & E1000_MANC_ASF_EN)) {
                        ret_val = true;
                        goto out;
                }
        }

out:
        return ret_val;
}