ixgbe: Add X553 PHY FC autoneg support

This patch adds X553 flow control auto negotiation for fiber and
backplain.  To enable this new function pointers were added as well
as creating a function to dynamically set function pointer we can't
define only on MAC type.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 211 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c
index 51b6ade6c83a..961ce3a8bfc7 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c
@@ -28,6 +28,9 @@
 
 static s32 ixgbe_setup_kr_speed_x550em(struct ixgbe_hw *, ixgbe_link_speed);
 static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *);
+static void ixgbe_fc_autoneg_fiber_x550em_a(struct ixgbe_hw *);
+static void ixgbe_fc_autoneg_backplane_x550em_a(struct ixgbe_hw *);
+static s32 ixgbe_setup_fc_backplane_x550em_a(struct ixgbe_hw *);
 
 static s32 ixgbe_get_invariants_X550_x(struct ixgbe_hw *hw)
 {
@@ -1639,6 +1642,27 @@ ixgbe_setup_sgmii(struct ixgbe_hw *hw, __always_unused ixgbe_link_speed speed,
 	return rc;
 }
 
+/** ixgbe_init_mac_link_ops_X550em_a - Init mac link function pointers
+ *  @hw: pointer to hardware structure
+ **/
+static void ixgbe_init_mac_link_ops_X550em_a(struct ixgbe_hw *hw)
+{
+	struct ixgbe_mac_info *mac = &hw->mac;
+
+	switch (mac->ops.get_media_type(hw)) {
+	case ixgbe_media_type_fiber:
+		mac->ops.setup_fc = NULL;
+		mac->ops.fc_autoneg = ixgbe_fc_autoneg_fiber_x550em_a;
+		break;
+	case ixgbe_media_type_backplane:
+		mac->ops.fc_autoneg = ixgbe_fc_autoneg_backplane_x550em_a;
+		mac->ops.setup_fc = ixgbe_setup_fc_backplane_x550em_a;
+		break;
+	default:
+		break;
+	}
+}
+
 /** ixgbe_init_mac_link_ops_X550em - init mac link function pointers
  *  @hw: pointer to hardware structure
  **/
@@ -1686,6 +1710,10 @@ static void ixgbe_init_mac_link_ops_X550em(struct ixgbe_hw *hw)
 	default:
 		break;
 	}
+
+	/* Additional modification for X550em_a devices */
+	if (hw->mac.type == ixgbe_mac_x550em_a)
+		ixgbe_init_mac_link_ops_X550em_a(hw);
 }
 
 /** ixgbe_setup_sfp_modules_X550em - Setup SFP module
@@ -2301,6 +2329,90 @@ static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *hw)
 	return rc;
 }
 
+/**
+ *  ixgbe_fc_autoneg_backplane_x550em_a - Enable flow control IEEE clause 37
+ *  @hw: pointer to hardware structure
+ **/
+static void ixgbe_fc_autoneg_backplane_x550em_a(struct ixgbe_hw *hw)
+{
+	u32 link_s1, lp_an_page_low, an_cntl_1;
+	s32 status = IXGBE_ERR_FC_NOT_NEGOTIATED;
+	ixgbe_link_speed speed;
+	bool link_up;
+
+	/* AN should have completed when the cable was plugged in.
+	 * Look for reasons to bail out.  Bail out if:
+	 * - FC autoneg is disabled, or if
+	 * - link is not up.
+	 */
+	if (hw->fc.disable_fc_autoneg) {
+		hw_err(hw, "Flow control autoneg is disabled");
+		goto out;
+	}
+
+	hw->mac.ops.check_link(hw, &speed, &link_up, false);
+	if (!link_up) {
+		hw_err(hw, "The link is down");
+		goto out;
+	}
+
+	/* Check at auto-negotiation has completed */
+	status = hw->mac.ops.read_iosf_sb_reg(hw,
+					IXGBE_KRM_LINK_S1(hw->bus.lan_id),
+					IXGBE_SB_IOSF_TARGET_KR_PHY, &link_s1);
+
+	if (status || (link_s1 & IXGBE_KRM_LINK_S1_MAC_AN_COMPLETE) == 0) {
+		hw_dbg(hw, "Auto-Negotiation did not complete\n");
+		status = IXGBE_ERR_FC_NOT_NEGOTIATED;
+		goto out;
+	}
+
+	/* Read the 10g AN autoc and LP ability registers and resolve
+	 * local flow control settings accordingly
+	 */
+	status = hw->mac.ops.read_iosf_sb_reg(hw,
+				IXGBE_KRM_AN_CNTL_1(hw->bus.lan_id),
+				IXGBE_SB_IOSF_TARGET_KR_PHY, &an_cntl_1);
+
+	if (status) {
+		hw_dbg(hw, "Auto-Negotiation did not complete\n");
+		goto out;
+	}
+
+	status = hw->mac.ops.read_iosf_sb_reg(hw,
+				IXGBE_KRM_LP_BASE_PAGE_HIGH(hw->bus.lan_id),
+				IXGBE_SB_IOSF_TARGET_KR_PHY, &lp_an_page_low);
+
+	if (status) {
+		hw_dbg(hw, "Auto-Negotiation did not complete\n");
+		goto out;
+	}
+
+	status = ixgbe_negotiate_fc(hw, an_cntl_1, lp_an_page_low,
+				    IXGBE_KRM_AN_CNTL_1_SYM_PAUSE,
+				    IXGBE_KRM_AN_CNTL_1_ASM_PAUSE,
+				    IXGBE_KRM_LP_BASE_PAGE_HIGH_SYM_PAUSE,
+				    IXGBE_KRM_LP_BASE_PAGE_HIGH_ASM_PAUSE);
+
+out:
+	if (!status) {
+		hw->fc.fc_was_autonegged = true;
+	} else {
+		hw->fc.fc_was_autonegged = false;
+		hw->fc.current_mode = hw->fc.requested_mode;
+	}
+}
+
+/**
+ *  ixgbe_fc_autoneg_fiber_x550em_a - passthrough FC settings
+ *  @hw: pointer to hardware structure
+ **/
+static void ixgbe_fc_autoneg_fiber_x550em_a(struct ixgbe_hw *hw)
+{
+	hw->fc.fc_was_autonegged = false;
+	hw->fc.current_mode = hw->fc.requested_mode;
+}
+
 /** ixgbe_enter_lplu_x550em - Transition to low power states
  *  @hw: pointer to hardware structure
  *
@@ -2749,6 +2861,102 @@ static void ixgbe_set_source_address_pruning_X550(struct ixgbe_hw *hw,
 }
 
 /**
+ *  ixgbe_setup_fc_backplane_x550em_a - Set up flow control
+ *  @hw: pointer to hardware structure
+ *
+ *  Called at init time to set up flow control.
+ **/
+static s32 ixgbe_setup_fc_backplane_x550em_a(struct ixgbe_hw *hw)
+{
+	s32 status = 0;
+	u32 link_ctrl = 0;
+	u32 an_cntl = 0;
+
+	/* Validate the requested mode */
+	if (hw->fc.strict_ieee && hw->fc.requested_mode == ixgbe_fc_rx_pause) {
+		hw_err(hw, "ixgbe_fc_rx_pause not valid in strict IEEE mode\n");
+		return IXGBE_ERR_INVALID_LINK_SETTINGS;
+	}
+
+	if (hw->fc.requested_mode == ixgbe_fc_default)
+		hw->fc.requested_mode = ixgbe_fc_full;
+
+	/* Set up the 1G and 10G flow control advertisement registers so the
+	 * HW will be able to do FC autoneg once the cable is plugged in.  If
+	 * we link at 10G, the 1G advertisement is harmless and vice versa.
+	 */
+	status = hw->mac.ops.read_iosf_sb_reg(hw,
+					IXGBE_KRM_AN_CNTL_1(hw->bus.lan_id),
+					IXGBE_SB_IOSF_TARGET_KR_PHY, &an_cntl);
+
+	if (status) {
+		hw_dbg(hw, "Auto-Negotiation did not complete\n");
+		return status;
+	}
+
+	/* The possible values of fc.requested_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.requested_mode) {
+	case ixgbe_fc_none:
+		/* Flow control completely disabled by software override. */
+		an_cntl &= ~(IXGBE_KRM_AN_CNTL_1_SYM_PAUSE |
+			     IXGBE_KRM_AN_CNTL_1_ASM_PAUSE);
+		break;
+	case ixgbe_fc_tx_pause:
+		/* Tx Flow control is enabled, and Rx Flow control is
+		 * disabled by software override.
+		 */
+		an_cntl |= IXGBE_KRM_AN_CNTL_1_ASM_PAUSE;
+		an_cntl &= ~IXGBE_KRM_AN_CNTL_1_SYM_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, as such we fall
+		 * through to the fc_full statement.  Later, we will
+		 * disable the adapter's ability to send PAUSE frames.
+		 */
+	case ixgbe_fc_full:
+		/* Flow control (both Rx and Tx) is enabled by SW override. */
+		an_cntl |= IXGBE_KRM_AN_CNTL_1_SYM_PAUSE |
+			   IXGBE_KRM_AN_CNTL_1_ASM_PAUSE;
+		break;
+	default:
+		hw_err(hw, "Flow control param set incorrectly\n");
+		return IXGBE_ERR_CONFIG;
+	}
+
+	status = hw->mac.ops.write_iosf_sb_reg(hw,
+					IXGBE_KRM_AN_CNTL_1(hw->bus.lan_id),
+					IXGBE_SB_IOSF_TARGET_KR_PHY, an_cntl);
+
+	/* Restart auto-negotiation. */
+	status = hw->mac.ops.read_iosf_sb_reg(hw,
+				IXGBE_KRM_LINK_CTRL_1(hw->bus.lan_id),
+				IXGBE_SB_IOSF_TARGET_KR_PHY, &link_ctrl);
+	if (status) {
+		hw_dbg(hw, "Auto-Negotiation did not complete\n");
+		return status;
+	}
+
+	link_ctrl |= IXGBE_KRM_LINK_CTRL_1_TETH_AN_RESTART;
+	status = hw->mac.ops.write_iosf_sb_reg(hw,
+				IXGBE_KRM_LINK_CTRL_1(hw->bus.lan_id),
+				IXGBE_SB_IOSF_TARGET_KR_PHY, link_ctrl);
+
+	return status;
+}
+
+/**
  * ixgbe_set_mux - Set mux for port 1 access with CS4227
  * @hw: pointer to hardware structure
  * @state: set mux if 1, clear if 0
@@ -2969,6 +3177,7 @@ static const struct ixgbe_mac_operations mac_ops_X550 = {
 	.prot_autoc_read	= prot_autoc_read_generic,
 	.prot_autoc_write	= prot_autoc_write_generic,
 	.setup_fc		= ixgbe_setup_fc_generic,
+	.fc_autoneg		= ixgbe_fc_autoneg,
 };
 
 static const struct ixgbe_mac_operations mac_ops_X550EM_x = {
@@ -2988,6 +3197,7 @@ static const struct ixgbe_mac_operations mac_ops_X550EM_x = {
 	.release_swfw_sync	= &ixgbe_release_swfw_sync_X550em,
 	.init_swfw_sync		= &ixgbe_init_swfw_sync_X540,
 	.setup_fc		= NULL, /* defined later */
+	.fc_autoneg		= ixgbe_fc_autoneg,
 	.read_iosf_sb_reg	= ixgbe_read_iosf_sb_reg_x550,
 	.write_iosf_sb_reg	= ixgbe_write_iosf_sb_reg_x550,
 };
@@ -3008,6 +3218,7 @@ static struct ixgbe_mac_operations mac_ops_x550em_a = {
 	.acquire_swfw_sync	= ixgbe_acquire_swfw_sync_x550em_a,
 	.release_swfw_sync	= ixgbe_release_swfw_sync_x550em_a,
 	.setup_fc		= ixgbe_setup_fc_x550em,
+	.fc_autoneg		= NULL, /* defined later */
 	.read_iosf_sb_reg	= ixgbe_read_iosf_sb_reg_x550a,
 	.write_iosf_sb_reg	= ixgbe_write_iosf_sb_reg_x550a,
 };