e1000_hw.c

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    int32_t ret_val;
    uint16_t eeprom_data;

    DEBUGFUNC("e1000_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(e1000_read_eeprom(hw, EEPROM_INIT_CONTROL2_REG, &eeprom_data) < 0) {
        DEBUGOUT("EEPROM Read Error\n");
        return -E1000_ERR_EEPROM;
    }

    if(hw->fc == e1000_fc_default) {
        if((eeprom_data & EEPROM_WORD0F_PAUSE_MASK) == 0)
            hw->fc = e1000_fc_none;
        else if((eeprom_data & EEPROM_WORD0F_PAUSE_MASK) == 
                EEPROM_WORD0F_ASM_DIR)
            hw->fc = e1000_fc_tx_pause;
        else
            hw->fc = e1000_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 == e1000_82542_rev2_0)
        hw->fc &= (~e1000_fc_tx_pause);

    if((hw->mac_type < e1000_82543) && (hw->report_tx_early == 1))
        hw->fc &= (~e1000_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 e1000_setup_pcs_link()
     * or e1000_phy_setup() is called.
     */
    if(hw->mac_type == e1000_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 == e1000_media_type_fiber) ?
              e1000_setup_fiber_link(hw) :
              e1000_setup_copper_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 & e1000_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 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 
e1000_setup_fiber_link(struct e1000_hw *hw)
{
    uint32_t ctrl;
    uint32_t status;
    uint32_t txcw = 0;
    uint32_t i;
    uint32_t signal;
    int32_t ret_val;

    DEBUGFUNC("e1000_setup_fiber_link");

    /* On adapters with a MAC newer that 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
     */
    ctrl = E1000_READ_REG(hw, CTRL);
    if(hw->mac_type > e1000_82544) signal = E1000_CTRL_SWDPIN1;
    else signal = 0;
   
    /* Take the link out of reset */
    ctrl &= ~(E1000_CTRL_LRST);
    
    e1000_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 e1000_fc_none:
        /* Flow control is completely disabled by a software over-ride. */
        txcw = (E1000_TXCW_ANE | E1000_TXCW_FD);
        break;
    case e1000_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 e1000_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 e1000_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).
     */
    if((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)) {
            /* AutoNeg failed to achieve a link, so we'll call 
             * e1000_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.
             */
            DEBUGOUT("Never got a valid link from auto-neg!!!\n");
            hw->autoneg_failed = 1;
            ret_val = e1000_check_for_link(hw);
            if(ret_val < 0) {
                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 0;
}

/******************************************************************************
* Detects which PHY is present and the speed and duplex
*
* hw - Struct containing variables accessed by shared code
******************************************************************************/
static int32_t 
e1000_setup_copper_link(struct e1000_hw *hw)
{
    uint32_t ctrl;
    int32_t ret_val;
    uint16_t i;
    uint16_t phy_data;

    DEBUGFUNC("e1000_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 > e1000_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);
        e1000_phy_hw_reset(hw);
    }

    /* Make sure we have a valid PHY */
    ret_val = e1000_detect_gig_phy(hw);
    if(ret_val < 0) {
        DEBUGOUT("Error, did not detect valid phy.\n");
        return ret_val;
    }
    DEBUGOUT1("Phy ID = %x \n", hw->phy_id);

    /* Enable CRS on TX. This must be set for half-duplex operation. */
    if(e1000_read_phy_reg(hw, M88E1000_PHY_SPEC_CTRL, &phy_data) < 0) {
        DEBUGOUT("PHY Read Error\n");
        return -E1000_ERR_PHY;
    }
    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(e1000_write_phy_reg(hw, M88E1000_PHY_SPEC_CTRL, phy_data) < 0) {
        DEBUGOUT("PHY Write Error\n");
        return -E1000_ERR_PHY;
    }

    /* Force TX_CLK in the Extended PHY Specific Control Register
     * to 25MHz clock.
     */
    if(e1000_read_phy_reg(hw, M88E1000_EXT_PHY_SPEC_CTRL, &phy_data) < 0) {
        DEBUGOUT("PHY Read Error\n");
        return -E1000_ERR_PHY;
    }
    phy_data |= M88E1000_EPSCR_TX_CLK_25;
    /* 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(e1000_write_phy_reg(hw, M88E1000_EXT_PHY_SPEC_CTRL, phy_data) < 0) {
        DEBUGOUT("PHY Write Error\n");
        return -E1000_ERR_PHY;
    }

    /* SW Reset the PHY so all changes take effect */
    ret_val = e1000_phy_reset(hw);
    if(ret_val < 0) {
        DEBUGOUT("Error Resetting the PHY\n");
        return ret_val;
    }
    
    /* Options:
     *   autoneg = 1 (default)
     *      PHY will advertise value(s) parsed from
     *      autoneg_advertised and fc