1 files changed, 138 insertions, 0 deletions

diff --git a/drivers/net/ixgbe/ixgbe_common.c b/drivers/net/ixgbe/ixgbe_common.c
index 13ad5ba66b63..5ae93989784f 100644
--- a/drivers/net/ixgbe/ixgbe_common.c
+++ b/drivers/net/ixgbe/ixgbe_common.c
@@ -1487,6 +1487,144 @@ s32 ixgbe_disable_mc_generic(struct ixgbe_hw *hw)
 }
 
 /**
+ *  ixgbe_fc_autoneg - Configure flow control
+ *  @hw: pointer to hardware structure
+ *
+ *  Negotiates flow control capabilities with link partner using autoneg and
+ *  applies the results.
+ **/
+s32 ixgbe_fc_autoneg(struct ixgbe_hw *hw)
+{
+        s32 ret_val = 0;
+        u32 i, reg, pcs_anadv_reg, pcs_lpab_reg;
+
+        reg = IXGBE_READ_REG(hw, IXGBE_PCS1GANA);
+
+        /*
+         * The possible values of fc.current_mode are:
+         * 0:  Flow control is completely disabled
+         * 1:  Rx flow control is enabled (we can receive pause frames,
+         *     but not send pause frames).
+         * 2:  Tx flow control is enabled (we can send pause frames but
+         *     we do not support receiving pause frames).
+         * 3:  Both Rx and Tx flow control (symmetric) are enabled.
+         * other: Invalid.
+         */
+        switch (hw->fc.current_mode) {
+        case ixgbe_fc_none:
+                /* Flow control completely disabled by software override. */
+                reg &= ~(IXGBE_PCS1GANA_SYM_PAUSE | IXGBE_PCS1GANA_ASM_PAUSE);
+                break;
+        case ixgbe_fc_rx_pause:
+                /*
+                 * Rx Flow control is enabled and Tx Flow control is
+                 * disabled by software override. 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.
+                 */
+                reg |= (IXGBE_PCS1GANA_SYM_PAUSE | IXGBE_PCS1GANA_ASM_PAUSE);
+                break;
+        case ixgbe_fc_tx_pause:
+                /*
+                 * Tx Flow control is enabled, and Rx Flow control is
+                 * disabled by software override.
+                 */
+                reg |= (IXGBE_PCS1GANA_ASM_PAUSE);
+                reg &= ~(IXGBE_PCS1GANA_SYM_PAUSE);
+                break;
+        case ixgbe_fc_full:
+                /* Flow control (both Rx and Tx) is enabled by SW override. */
+                reg |= (IXGBE_PCS1GANA_SYM_PAUSE | IXGBE_PCS1GANA_ASM_PAUSE);
+                break;
+        default:
+                hw_dbg(hw, "Flow control param set incorrectly\n");
+                ret_val = -IXGBE_ERR_CONFIG;
+                goto out;
+                break;
+        }
+
+        IXGBE_WRITE_REG(hw, IXGBE_PCS1GANA, reg);
+        reg = IXGBE_READ_REG(hw, IXGBE_PCS1GLCTL);
+
+        /* Set PCS register for autoneg */
+        /* Enable and restart autoneg */
+        reg |= IXGBE_PCS1GLCTL_AN_ENABLE | IXGBE_PCS1GLCTL_AN_RESTART;
+
+        /* Disable AN timeout */
+        if (hw->fc.strict_ieee)
+                reg &= ~IXGBE_PCS1GLCTL_AN_1G_TIMEOUT_EN;
+
+        hw_dbg(hw, "Configuring Autoneg; PCS_LCTL = 0x%08X\n", reg);
+        IXGBE_WRITE_REG(hw, IXGBE_PCS1GLCTL, reg);
+
+        /* See if autonegotiation has succeeded */
+        hw->mac.autoneg_succeeded = 0;
+        for (i = 0; i < FIBER_LINK_UP_LIMIT; i++) {
+                msleep(10);
+                reg = IXGBE_READ_REG(hw, IXGBE_PCS1GLSTA);
+                if ((reg & (IXGBE_PCS1GLSTA_LINK_OK |
+                     IXGBE_PCS1GLSTA_AN_COMPLETE)) ==
+                    (IXGBE_PCS1GLSTA_LINK_OK |
+                     IXGBE_PCS1GLSTA_AN_COMPLETE)) {
+                        if (!(reg & IXGBE_PCS1GLSTA_AN_TIMED_OUT))
+                                hw->mac.autoneg_succeeded = 1;
+                        break;
+                }
+        }
+
+        if (!hw->mac.autoneg_succeeded) {
+                /* Autoneg failed to achieve a link, so we turn fc off */
+                hw->fc.current_mode = ixgbe_fc_none;
+                hw_dbg(hw, "Flow Control = NONE.\n");
+                goto out;
+        }
+
+        /*
+         * Read the AN advertisement and LP ability registers and resolve
+         * local flow control settings accordingly
+         */
+        pcs_anadv_reg = IXGBE_READ_REG(hw, IXGBE_PCS1GANA);
+        pcs_lpab_reg = IXGBE_READ_REG(hw, IXGBE_PCS1GANLP);
+        if ((pcs_anadv_reg & IXGBE_PCS1GANA_SYM_PAUSE) &&
+                (pcs_lpab_reg & IXGBE_PCS1GANA_SYM_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 == ixgbe_fc_full) {
+                        hw->fc.current_mode = ixgbe_fc_full;
+                        hw_dbg(hw, "Flow Control = FULL.\n");
+                } else {
+                        hw->fc.current_mode = ixgbe_fc_rx_pause;
+                        hw_dbg(hw, "Flow Control = RX PAUSE frames only.\n");
+                }
+        } else if (!(pcs_anadv_reg & IXGBE_PCS1GANA_SYM_PAUSE) &&
+                   (pcs_anadv_reg & IXGBE_PCS1GANA_ASM_PAUSE) &&
+                   (pcs_lpab_reg & IXGBE_PCS1GANA_SYM_PAUSE) &&
+                   (pcs_lpab_reg & IXGBE_PCS1GANA_ASM_PAUSE)) {
+                hw->fc.current_mode = ixgbe_fc_tx_pause;
+                hw_dbg(hw, "Flow Control = TX PAUSE frames only.\n");
+        } else if ((pcs_anadv_reg & IXGBE_PCS1GANA_SYM_PAUSE) &&
+                   (pcs_anadv_reg & IXGBE_PCS1GANA_ASM_PAUSE) &&
+                   !(pcs_lpab_reg & IXGBE_PCS1GANA_SYM_PAUSE) &&
+                   (pcs_lpab_reg & IXGBE_PCS1GANA_ASM_PAUSE)) {
+                hw->fc.current_mode = ixgbe_fc_rx_pause;
+                hw_dbg(hw, "Flow Control = RX PAUSE frames only.\n");
+        } else {
+                hw->fc.current_mode = ixgbe_fc_none;
+                hw_dbg(hw, "Flow Control = NONE.\n");
+        }
+
+out:
+        return ret_val;
+}
+
+/**
  *  ixgbe_disable_pcie_master - Disable PCI-express master access
  *  @hw: pointer to hardware structure
  *