From daf56e406a94675d454f996cab56c3d0b0a0d8a6 Mon Sep 17 00:00:00 2001 From: Carolyn Wyborny Date: Tue, 23 Oct 2012 12:54:33 +0000 Subject: igb: Fix SerDes autoneg flow control. This patch enables flow control to be set in SerDes autoneg mode. This is done the way it is done for copper, but relies on a different set of register/bit checks since this is all done within the MAC registers. Signed-off-by: Carolyn Wyborny Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/igb/e1000_mac.c | 124 +++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) (limited to 'drivers/net/ethernet/intel/igb/e1000_mac.c') diff --git a/drivers/net/ethernet/intel/igb/e1000_mac.c b/drivers/net/ethernet/intel/igb/e1000_mac.c index 7acddfe9e6d5..101e6e4da97f 100644 --- a/drivers/net/ethernet/intel/igb/e1000_mac.c +++ b/drivers/net/ethernet/intel/igb/e1000_mac.c @@ -839,6 +839,7 @@ 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; @@ -1040,6 +1041,129 @@ s32 igb_config_fc_after_link_up(struct e1000_hw *hw) 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; -- cgit v1.2.3-59-g8ed1b