numam-dpdk/drivers/net/e1000/base/e1000_82540.c

/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2001-2020 Intel Corporation
 */

/*
 * 82540EM Gigabit Ethernet Controller
 * 82540EP Gigabit Ethernet Controller
 * 82545EM Gigabit Ethernet Controller (Copper)
 * 82545EM Gigabit Ethernet Controller (Fiber)
 * 82545GM Gigabit Ethernet Controller
 * 82546EB Gigabit Ethernet Controller (Copper)
 * 82546EB Gigabit Ethernet Controller (Fiber)
 * 82546GB Gigabit Ethernet Controller
 */

#include "e1000_api.h"

STATIC s32  e1000_init_phy_params_82540(struct e1000_hw *hw);
STATIC s32  e1000_init_nvm_params_82540(struct e1000_hw *hw);
STATIC s32  e1000_init_mac_params_82540(struct e1000_hw *hw);
STATIC s32  e1000_adjust_serdes_amplitude_82540(struct e1000_hw *hw);
STATIC void e1000_clear_hw_cntrs_82540(struct e1000_hw *hw);
STATIC s32  e1000_init_hw_82540(struct e1000_hw *hw);
STATIC s32  e1000_reset_hw_82540(struct e1000_hw *hw);
STATIC s32  e1000_set_phy_mode_82540(struct e1000_hw *hw);
STATIC s32  e1000_set_vco_speed_82540(struct e1000_hw *hw);
STATIC s32  e1000_setup_copper_link_82540(struct e1000_hw *hw);
STATIC s32  e1000_setup_fiber_serdes_link_82540(struct e1000_hw *hw);
STATIC void e1000_power_down_phy_copper_82540(struct e1000_hw *hw);
STATIC s32  e1000_read_mac_addr_82540(struct e1000_hw *hw);

/**
 * e1000_init_phy_params_82540 - Init PHY func ptrs.
 * @hw: pointer to the HW structure
 **/
STATIC s32 e1000_init_phy_params_82540(struct e1000_hw *hw)
{
	struct e1000_phy_info *phy = &hw->phy;
	s32 ret_val;

	phy->addr		= 1;
	phy->autoneg_mask	= AUTONEG_ADVERTISE_SPEED_DEFAULT;
	phy->reset_delay_us	= 10000;
	phy->type		= e1000_phy_m88;

	/* Function Pointers */
	phy->ops.check_polarity	= e1000_check_polarity_m88;
	phy->ops.commit		= e1000_phy_sw_reset_generic;
	phy->ops.force_speed_duplex = e1000_phy_force_speed_duplex_m88;
	phy->ops.get_cable_length = e1000_get_cable_length_m88;
	phy->ops.get_cfg_done	= e1000_get_cfg_done_generic;
	phy->ops.read_reg	= e1000_read_phy_reg_m88;
	phy->ops.reset		= e1000_phy_hw_reset_generic;
	phy->ops.write_reg	= e1000_write_phy_reg_m88;
	phy->ops.get_info	= e1000_get_phy_info_m88;
	phy->ops.power_up	= e1000_power_up_phy_copper;
	phy->ops.power_down	= e1000_power_down_phy_copper_82540;

	ret_val = e1000_get_phy_id(hw);
	if (ret_val)
		goto out;

	/* Verify phy id */
	switch (hw->mac.type) {
	case e1000_82540:
	case e1000_82545:
	case e1000_82545_rev_3:
	case e1000_82546:
	case e1000_82546_rev_3:
		if (phy->id == M88E1011_I_PHY_ID)
			break;
		/* Fall Through */
	default:
		ret_val = -E1000_ERR_PHY;
		goto out;
		break;
	}

out:
	return ret_val;
}

/**
 * e1000_init_nvm_params_82540 - Init NVM func ptrs.
 * @hw: pointer to the HW structure
 **/
STATIC s32 e1000_init_nvm_params_82540(struct e1000_hw *hw)
{
	struct e1000_nvm_info *nvm = &hw->nvm;
	u32 eecd = E1000_READ_REG(hw, E1000_EECD);

	DEBUGFUNC("e1000_init_nvm_params_82540");

	nvm->type = e1000_nvm_eeprom_microwire;
	nvm->delay_usec = 50;
	nvm->opcode_bits = 3;
	switch (nvm->override) {
	case e1000_nvm_override_microwire_large:
		nvm->address_bits = 8;
		nvm->word_size = 256;
		break;
	case e1000_nvm_override_microwire_small:
		nvm->address_bits = 6;
		nvm->word_size = 64;
		break;
	default:
		nvm->address_bits = eecd & E1000_EECD_SIZE ? 8 : 6;
		nvm->word_size = eecd & E1000_EECD_SIZE ? 256 : 64;
		break;
	}

	/* Function Pointers */
	nvm->ops.acquire	= e1000_acquire_nvm_generic;
	nvm->ops.read		= e1000_read_nvm_microwire;
	nvm->ops.release	= e1000_release_nvm_generic;
	nvm->ops.update		= e1000_update_nvm_checksum_generic;
	nvm->ops.valid_led_default = e1000_valid_led_default_generic;
	nvm->ops.validate	= e1000_validate_nvm_checksum_generic;
	nvm->ops.write		= e1000_write_nvm_microwire;

	return E1000_SUCCESS;
}

/**
 * e1000_init_mac_params_82540 - Init MAC func ptrs.
 * @hw: pointer to the HW structure
 **/
STATIC s32 e1000_init_mac_params_82540(struct e1000_hw *hw)
{
	struct e1000_mac_info *mac = &hw->mac;
	s32 ret_val = E1000_SUCCESS;

	DEBUGFUNC("e1000_init_mac_params_82540");

	/* Set media type */
	switch (hw->device_id) {
	case E1000_DEV_ID_82545EM_FIBER:
	case E1000_DEV_ID_82545GM_FIBER:
	case E1000_DEV_ID_82546EB_FIBER:
	case E1000_DEV_ID_82546GB_FIBER:
		hw->phy.media_type = e1000_media_type_fiber;
		break;
	case E1000_DEV_ID_82545GM_SERDES:
	case E1000_DEV_ID_82546GB_SERDES:
		hw->phy.media_type = e1000_media_type_internal_serdes;
		break;
	default:
		hw->phy.media_type = e1000_media_type_copper;
		break;
	}

	/* Set mta register count */
	mac->mta_reg_count = 128;
	/* Set rar entry count */
	mac->rar_entry_count = E1000_RAR_ENTRIES;

	/* Function pointers */

	/* bus type/speed/width */
	mac->ops.get_bus_info = e1000_get_bus_info_pci_generic;
	/* function id */
	mac->ops.set_lan_id = e1000_set_lan_id_multi_port_pci;
	/* reset */
	mac->ops.reset_hw = e1000_reset_hw_82540;
	/* hw initialization */
	mac->ops.init_hw = e1000_init_hw_82540;
	/* link setup */
	mac->ops.setup_link = e1000_setup_link_generic;
	/* physical interface setup */
	mac->ops.setup_physical_interface =
		(hw->phy.media_type == e1000_media_type_copper)
			? e1000_setup_copper_link_82540
			: e1000_setup_fiber_serdes_link_82540;
	/* check for link */
	switch (hw->phy.media_type) {
	case e1000_media_type_copper:
		mac->ops.check_for_link = e1000_check_for_copper_link_generic;
		break;
	case e1000_media_type_fiber:
		mac->ops.check_for_link = e1000_check_for_fiber_link_generic;
		break;
	case e1000_media_type_internal_serdes:
		mac->ops.check_for_link = e1000_check_for_serdes_link_generic;
		break;
	default:
		ret_val = -E1000_ERR_CONFIG;
		goto out;
		break;
	}
	/* link info */
	mac->ops.get_link_up_info =
		(hw->phy.media_type == e1000_media_type_copper)
			? e1000_get_speed_and_duplex_copper_generic
			: e1000_get_speed_and_duplex_fiber_serdes_generic;
	/* multicast address update */
	mac->ops.update_mc_addr_list = e1000_update_mc_addr_list_generic;
	/* writing VFTA */
	mac->ops.write_vfta = e1000_write_vfta_generic;
	/* clearing VFTA */
	mac->ops.clear_vfta = e1000_clear_vfta_generic;
	/* read mac address */
	mac->ops.read_mac_addr = e1000_read_mac_addr_82540;
	/* ID LED init */
	mac->ops.id_led_init = e1000_id_led_init_generic;
	/* setup LED */
	mac->ops.setup_led = e1000_setup_led_generic;
	/* cleanup LED */
	mac->ops.cleanup_led = e1000_cleanup_led_generic;
	/* turn on/off LED */
	mac->ops.led_on = e1000_led_on_generic;
	mac->ops.led_off = e1000_led_off_generic;
	/* clear hardware counters */
	mac->ops.clear_hw_cntrs = e1000_clear_hw_cntrs_82540;

out:
	return ret_val;
}

/**
 * e1000_init_function_pointers_82540 - Init func ptrs.
 * @hw: pointer to the HW structure
 *
 * Called to initialize all function pointers and parameters.
 **/
void e1000_init_function_pointers_82540(struct e1000_hw *hw)
{
	DEBUGFUNC("e1000_init_function_pointers_82540");

	hw->mac.ops.init_params = e1000_init_mac_params_82540;
	hw->nvm.ops.init_params = e1000_init_nvm_params_82540;
	hw->phy.ops.init_params = e1000_init_phy_params_82540;
}

/**
 *  e1000_reset_hw_82540 - Reset hardware
 *  @hw: pointer to the HW structure
 *
 *  This resets the hardware into a known state.
 **/
STATIC s32 e1000_reset_hw_82540(struct e1000_hw *hw)
{
	u32 ctrl, manc;
	s32 ret_val = E1000_SUCCESS;

	DEBUGFUNC("e1000_reset_hw_82540");

	DEBUGOUT("Masking off all interrupts\n");
	E1000_WRITE_REG(hw, E1000_IMC, 0xFFFFFFFF);

	E1000_WRITE_REG(hw, E1000_RCTL, 0);
	E1000_WRITE_REG(hw, E1000_TCTL, E1000_TCTL_PSP);
	E1000_WRITE_FLUSH(hw);

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

	ctrl = E1000_READ_REG(hw, E1000_CTRL);

	DEBUGOUT("Issuing a global reset to 82540/82545/82546 MAC\n");
	switch (hw->mac.type) {
	case e1000_82545_rev_3:
	case e1000_82546_rev_3:
		E1000_WRITE_REG(hw, E1000_CTRL_DUP, ctrl | E1000_CTRL_RST);
		break;
	default:
		/*
		 * These controllers can't ack the 64-bit write when
		 * issuing the reset, so we use IO-mapping as a
		 * workaround to issue the reset.
		 */
		E1000_WRITE_REG_IO(hw, E1000_CTRL, ctrl | E1000_CTRL_RST);
		break;
	}

	/* Wait for EEPROM reload */
	msec_delay(5);

	/* Disable HW ARPs on ASF enabled adapters */
	manc = E1000_READ_REG(hw, E1000_MANC);
	manc &= ~E1000_MANC_ARP_EN;
	E1000_WRITE_REG(hw, E1000_MANC, manc);

	E1000_WRITE_REG(hw, E1000_IMC, 0xffffffff);
	E1000_READ_REG(hw, E1000_ICR);

	return ret_val;
}

/**
 *  e1000_init_hw_82540 - Initialize hardware
 *  @hw: pointer to the HW structure
 *
 *  This inits the hardware readying it for operation.
 **/
STATIC s32 e1000_init_hw_82540(struct e1000_hw *hw)
{
	struct e1000_mac_info *mac = &hw->mac;
	u32 txdctl, ctrl_ext;
	s32 ret_val;
	u16 i;

	DEBUGFUNC("e1000_init_hw_82540");

	/* Initialize identification LED */
	ret_val = mac->ops.id_led_init(hw);
	if (ret_val) {
		DEBUGOUT("Error initializing identification LED\n");
		/* This is not fatal and we should not stop init due to this */
	}

	/* Disabling VLAN filtering */
	DEBUGOUT("Initializing the IEEE VLAN\n");
	if (mac->type < e1000_82545_rev_3)
		E1000_WRITE_REG(hw, E1000_VET, 0);

	mac->ops.clear_vfta(hw);

	/* Setup the receive address. */
	e1000_init_rx_addrs_generic(hw, mac->rar_entry_count);

	/* Zero out the Multicast HASH table */
	DEBUGOUT("Zeroing the MTA\n");
	for (i = 0; i < mac->mta_reg_count; i++) {
		E1000_WRITE_REG_ARRAY(hw, E1000_MTA, i, 0);
		/*
		 * Avoid back to back register writes by adding the register
		 * read (flush).  This is to protect against some strange
		 * bridge configurations that may issue Memory Write Block
		 * (MWB) to our register space.  The *_rev_3 hardware at
		 * least doesn't respond correctly to every other dword in an
		 * MWB to our register space.
		 */
		E1000_WRITE_FLUSH(hw);
	}

	if (mac->type < e1000_82545_rev_3)
		e1000_pcix_mmrbc_workaround_generic(hw);

	/* Setup link and flow control */
	ret_val = mac->ops.setup_link(hw);

	txdctl = E1000_READ_REG(hw, E1000_TXDCTL(0));
	txdctl = (txdctl & ~E1000_TXDCTL_WTHRESH) |
		  E1000_TXDCTL_FULL_TX_DESC_WB;
	E1000_WRITE_REG(hw, E1000_TXDCTL(0), txdctl);

	/*
	 * 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.
	 */
	e1000_clear_hw_cntrs_82540(hw);

	if ((hw->device_id == E1000_DEV_ID_82546GB_QUAD_COPPER) ||
	    (hw->device_id == E1000_DEV_ID_82546GB_QUAD_COPPER_KSP3)) {
		ctrl_ext = E1000_READ_REG(hw, E1000_CTRL_EXT);
		/*
		 * Relaxed ordering must be disabled to avoid a parity
		 * error crash in a PCI slot.
		 */
		ctrl_ext |= E1000_CTRL_EXT_RO_DIS;
		E1000_WRITE_REG(hw, E1000_CTRL_EXT, ctrl_ext);
	}

	return ret_val;
}

/**
 *  e1000_setup_copper_link_82540 - Configure copper link settings
 *  @hw: pointer to the HW structure
 *
 *  Calls the appropriate function to configure the link for auto-neg or forced
 *  speed and duplex.  Then we check for link, once link is established calls
 *  to configure collision distance and flow control are called.  If link is
 *  not established, we return -E1000_ERR_PHY (-2).
 **/
STATIC s32 e1000_setup_copper_link_82540(struct e1000_hw *hw)
{
	u32 ctrl;
	s32 ret_val;
	u16 data;

	DEBUGFUNC("e1000_setup_copper_link_82540");

	ctrl = E1000_READ_REG(hw, E1000_CTRL);
	ctrl |= E1000_CTRL_SLU;
	ctrl &= ~(E1000_CTRL_FRCSPD | E1000_CTRL_FRCDPX);
	E1000_WRITE_REG(hw, E1000_CTRL, ctrl);

	ret_val = e1000_set_phy_mode_82540(hw);
	if (ret_val)
		goto out;

	if (hw->mac.type == e1000_82545_rev_3 ||
	    hw->mac.type == e1000_82546_rev_3) {
		ret_val = hw->phy.ops.read_reg(hw, M88E1000_PHY_SPEC_CTRL,
					       &data);
		if (ret_val)
			goto out;
		data |= 0x00000008;
		ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_SPEC_CTRL,
						data);
		if (ret_val)
			goto out;
	}

	ret_val = e1000_copper_link_setup_m88(hw);
	if (ret_val)
		goto out;

	ret_val = e1000_setup_copper_link_generic(hw);

out:
	return ret_val;
}

/**
 *  e1000_setup_fiber_serdes_link_82540 - Setup link for fiber/serdes
 *  @hw: pointer to the HW structure
 *
 *  Set the output amplitude to the value in the EEPROM and adjust the VCO
 *  speed to improve Bit Error Rate (BER) performance.  Configures collision
 *  distance and flow control for fiber and serdes links.  Upon successful
 *  setup, poll for link.
 **/
STATIC s32 e1000_setup_fiber_serdes_link_82540(struct e1000_hw *hw)
{
	struct e1000_mac_info *mac = &hw->mac;
	s32 ret_val = E1000_SUCCESS;

	DEBUGFUNC("e1000_setup_fiber_serdes_link_82540");

	switch (mac->type) {
	case e1000_82545_rev_3:
	case e1000_82546_rev_3:
		if (hw->phy.media_type == e1000_media_type_internal_serdes) {
			/*
			 * If we're on serdes media, adjust the output
			 * amplitude to value set in the EEPROM.
			 */
			ret_val = e1000_adjust_serdes_amplitude_82540(hw);
			if (ret_val)
				goto out;
		}
		/* Adjust VCO speed to improve BER performance */
		ret_val = e1000_set_vco_speed_82540(hw);
		if (ret_val)
			goto out;
	default:
		break;
	}

	ret_val = e1000_setup_fiber_serdes_link_generic(hw);

out:
	return ret_val;
}

/**
 *  e1000_adjust_serdes_amplitude_82540 - Adjust amplitude based on EEPROM
 *  @hw: pointer to the HW structure
 *
 *  Adjust the SERDES output amplitude based on the EEPROM settings.
 **/
STATIC s32 e1000_adjust_serdes_amplitude_82540(struct e1000_hw *hw)
{
	s32 ret_val;
	u16 nvm_data;

	DEBUGFUNC("e1000_adjust_serdes_amplitude_82540");

	ret_val = hw->nvm.ops.read(hw, NVM_SERDES_AMPLITUDE, 1, &nvm_data);
	if (ret_val)
		goto out;

	if (nvm_data != NVM_RESERVED_WORD) {
		/* Adjust serdes output amplitude only. */
		nvm_data &= NVM_SERDES_AMPLITUDE_MASK;
		ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_EXT_CTRL,
						nvm_data);
		if (ret_val)
			goto out;
	}

out:
	return ret_val;
}

/**
 *  e1000_set_vco_speed_82540 - Set VCO speed for better performance
 *  @hw: pointer to the HW structure
 *
 *  Set the VCO speed to improve Bit Error Rate (BER) performance.
 **/
STATIC s32 e1000_set_vco_speed_82540(struct e1000_hw *hw)
{
	s32  ret_val;
	u16 default_page = 0;
	u16 phy_data;

	DEBUGFUNC("e1000_set_vco_speed_82540");

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

	ret_val = hw->phy.ops.read_reg(hw, M88E1000_PHY_PAGE_SELECT,
				       &default_page);
	if (ret_val)
		goto out;

	ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_PAGE_SELECT, 0x0005);
	if (ret_val)
		goto out;

	ret_val = hw->phy.ops.read_reg(hw, M88E1000_PHY_GEN_CONTROL, &phy_data);
	if (ret_val)
		goto out;

	phy_data &= ~M88E1000_PHY_VCO_REG_BIT8;
	ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_GEN_CONTROL, phy_data);
	if (ret_val)
		goto out;

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

	ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_PAGE_SELECT, 0x0004);
	if (ret_val)
		goto out;

	ret_val = hw->phy.ops.read_reg(hw, M88E1000_PHY_GEN_CONTROL, &phy_data);
	if (ret_val)
		goto out;

	phy_data |= M88E1000_PHY_VCO_REG_BIT11;
	ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_GEN_CONTROL, phy_data);
	if (ret_val)
		goto out;

	ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_PAGE_SELECT,
					default_page);

out:
	return ret_val;
}

/**
 *  e1000_set_phy_mode_82540 - Set PHY to class A mode
 *  @hw: pointer to the HW structure
 *
 *  Sets the PHY to class A mode and assumes the following operations will
 *  follow to enable the new class mode:
 *    1.  Do a PHY soft reset.
 *    2.  Restart auto-negotiation or force link.
 **/
STATIC s32 e1000_set_phy_mode_82540(struct e1000_hw *hw)
{
	s32 ret_val = E1000_SUCCESS;
	u16 nvm_data;

	DEBUGFUNC("e1000_set_phy_mode_82540");

	if (hw->mac.type != e1000_82545_rev_3)
		goto out;

	ret_val = hw->nvm.ops.read(hw, NVM_PHY_CLASS_WORD, 1, &nvm_data);
	if (ret_val) {
		ret_val = -E1000_ERR_PHY;
		goto out;
	}

	if ((nvm_data != NVM_RESERVED_WORD) && (nvm_data & NVM_PHY_CLASS_A)) {
		ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_PAGE_SELECT,
						0x000B);
		if (ret_val) {
			ret_val = -E1000_ERR_PHY;
			goto out;
		}
		ret_val = hw->phy.ops.write_reg(hw, M88E1000_PHY_GEN_CONTROL,
						0x8104);
		if (ret_val) {
			ret_val = -E1000_ERR_PHY;
			goto out;
		}

	}

out:
	return ret_val;
}

/**
 * e1000_power_down_phy_copper_82540 - Remove link in case of PHY power down
 * @hw: pointer to the HW structure
 *
 * In the case of a PHY power down to save power, or to turn off link during a
 * driver unload, or wake on lan is not enabled, remove the link.
 **/
STATIC void e1000_power_down_phy_copper_82540(struct e1000_hw *hw)
{
	/* If the management interface is not enabled, then power down */
	if (!(E1000_READ_REG(hw, E1000_MANC) & E1000_MANC_SMBUS_EN))
		e1000_power_down_phy_copper(hw);

	return;
}

/**
 *  e1000_clear_hw_cntrs_82540 - Clear device specific hardware counters
 *  @hw: pointer to the HW structure
 *
 *  Clears the hardware counters by reading the counter registers.
 **/
STATIC void e1000_clear_hw_cntrs_82540(struct e1000_hw *hw)
{
	DEBUGFUNC("e1000_clear_hw_cntrs_82540");

	e1000_clear_hw_cntrs_base_generic(hw);

	E1000_READ_REG(hw, E1000_PRC64);
	E1000_READ_REG(hw, E1000_PRC127);
	E1000_READ_REG(hw, E1000_PRC255);
	E1000_READ_REG(hw, E1000_PRC511);
	E1000_READ_REG(hw, E1000_PRC1023);
	E1000_READ_REG(hw, E1000_PRC1522);
	E1000_READ_REG(hw, E1000_PTC64);
	E1000_READ_REG(hw, E1000_PTC127);
	E1000_READ_REG(hw, E1000_PTC255);
	E1000_READ_REG(hw, E1000_PTC511);
	E1000_READ_REG(hw, E1000_PTC1023);
	E1000_READ_REG(hw, E1000_PTC1522);

	E1000_READ_REG(hw, E1000_ALGNERRC);
	E1000_READ_REG(hw, E1000_RXERRC);
	E1000_READ_REG(hw, E1000_TNCRS);
	E1000_READ_REG(hw, E1000_CEXTERR);
	E1000_READ_REG(hw, E1000_TSCTC);
	E1000_READ_REG(hw, E1000_TSCTFC);

	E1000_READ_REG(hw, E1000_MGTPRC);
	E1000_READ_REG(hw, E1000_MGTPDC);
	E1000_READ_REG(hw, E1000_MGTPTC);
}

/**
 *  e1000_read_mac_addr_82540 - Read device MAC address
 *  @hw: pointer to the HW structure
 *
 *  Reads the device MAC address from the EEPROM and stores the value.
 *  Since devices with two ports use the same EEPROM, we increment the
 *  last bit in the MAC address for the second port.
 *
 *  This version is being used over generic because of customer issues
 *  with VmWare and Virtual Box when using generic. It seems in
 *  the emulated 82545, RAR[0] does NOT have a valid address after a
 *  reset, this older method works and using this breaks nothing for
 *  these legacy adapters.
 **/
s32 e1000_read_mac_addr_82540(struct e1000_hw *hw)
{
	s32  ret_val = E1000_SUCCESS;
	u16 offset, nvm_data, i;

	DEBUGFUNC("e1000_read_mac_addr");

	for (i = 0; i < ETH_ADDR_LEN; i += 2) {
		offset = i >> 1;
		ret_val = hw->nvm.ops.read(hw, offset, 1, &nvm_data);
		if (ret_val) {
			DEBUGOUT("NVM Read Error\n");
			goto out;
		}
		hw->mac.perm_addr[i] = (u8)(nvm_data & 0xFF);
		hw->mac.perm_addr[i+1] = (u8)(nvm_data >> 8);
	}

	/* Flip last bit of mac address if we're on second port */
	if (hw->bus.func == E1000_FUNC_1)
		hw->mac.perm_addr[5] ^= 1;

	for (i = 0; i < ETH_ADDR_LEN; i++)
		hw->mac.addr[i] = hw->mac.perm_addr[i];

out:
	return ret_val;
}