ixgbe: Fix flow control for Xeon D KR backplane

Xeon D KR backplane is different from other backplanes,
in that we can't use auto-negotiation to determine the
mode. Instead, use whatever the user configured.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c

@@ -1192,6 +1192,7 @@ static const struct ixgbe_mac_operations mac_ops_82598 = {
 	.clear_vfta		= &ixgbe_clear_vfta_82598,
 	.set_vfta		= &ixgbe_set_vfta_82598,
 	.fc_enable		= &ixgbe_fc_enable_82598,
+	.setup_fc		= ixgbe_setup_fc_generic,
 	.set_fw_drv_ver         = NULL,
 	.acquire_swfw_sync      = &ixgbe_acquire_swfw_sync,
 	.release_swfw_sync      = &ixgbe_release_swfw_sync,

drivers/net/ethernet/intel/ixgbe/ixgbe_82599.c

@@ -2220,6 +2220,7 @@ static const struct ixgbe_mac_operations mac_ops_82599 = {
 	.clear_vfta             = &ixgbe_clear_vfta_generic,
 	.set_vfta               = &ixgbe_set_vfta_generic,
 	.fc_enable              = &ixgbe_fc_enable_generic,
+	.setup_fc		= ixgbe_setup_fc_generic,
 	.set_fw_drv_ver         = &ixgbe_set_fw_drv_ver_generic,
 	.init_uta_tables        = &ixgbe_init_uta_tables_generic,
 	.setup_sfp              = &ixgbe_setup_sfp_modules_82599,

drivers/net/ethernet/intel/ixgbe/ixgbe_common.c

 /*******************************************************************************
 
   Intel 10 Gigabit PCI Express Linux driver
-  Copyright(c) 1999 - 2015 Intel Corporation.
+  Copyright(c) 1999 - 2016 Intel Corporation.
 
   This program is free software; you can redistribute it and/or modify it
   under the terms and conditions of the GNU General Public License,
@@ -111,12 +111,12 @@ bool ixgbe_device_supports_autoneg_fc(struct ixgbe_hw *hw)
 }
 
 /**
- *  ixgbe_setup_fc - Set up flow control
+ *  ixgbe_setup_fc_generic - Set up flow control
  *  @hw: pointer to hardware structure
  *
  *  Called at init time to set up flow control.
  **/
-static s32 ixgbe_setup_fc(struct ixgbe_hw *hw)
+s32 ixgbe_setup_fc_generic(struct ixgbe_hw *hw)
 {
 	s32 ret_val = 0;
 	u32 reg = 0, reg_bp = 0;
@@ -296,7 +296,7 @@ s32 ixgbe_start_hw_generic(struct ixgbe_hw *hw)
 	IXGBE_WRITE_FLUSH(hw);
 
 	/* Setup flow control */
-	ret_val = ixgbe_setup_fc(hw);
+	ret_val = hw->mac.ops.setup_fc(hw);
 	if (ret_val)
 		return ret_val;
 

drivers/net/ethernet/intel/ixgbe/ixgbe_common.h

 /*******************************************************************************
 
   Intel 10 Gigabit PCI Express Linux driver
-  Copyright(c) 1999 - 2014 Intel Corporation.
+  Copyright(c) 1999 - 2016 Intel Corporation.
 
   This program is free software; you can redistribute it and/or modify it
   under the terms and conditions of the GNU General Public License,
@@ -81,6 +81,7 @@ s32 ixgbe_disable_rx_buff_generic(struct ixgbe_hw *hw);
 s32 ixgbe_enable_rx_buff_generic(struct ixgbe_hw *hw);
 s32 ixgbe_enable_rx_dma_generic(struct ixgbe_hw *hw, u32 regval);
 s32 ixgbe_fc_enable_generic(struct ixgbe_hw *hw);
+s32 ixgbe_setup_fc_generic(struct ixgbe_hw *);
 bool ixgbe_device_supports_autoneg_fc(struct ixgbe_hw *hw);
 void ixgbe_fc_autoneg(struct ixgbe_hw *hw);
 

drivers/net/ethernet/intel/ixgbe/ixgbe_type.h

@@ -3308,6 +3308,7 @@ struct ixgbe_mac_operations {
 
 	/* Flow Control */
 	s32 (*fc_enable)(struct ixgbe_hw *);
+	s32 (*setup_fc)(struct ixgbe_hw *);
 
 	/* Manageability interface */
 	s32 (*set_fw_drv_ver)(struct ixgbe_hw *, u8, u8, u8, u8);
@@ -3525,6 +3526,7 @@ struct ixgbe_info {
 
 #define IXGBE_KRM_PORT_CAR_GEN_CTRL(P)	((P) ? 0x8010 : 0x4010)
 #define IXGBE_KRM_LINK_CTRL_1(P)	((P) ? 0x820C : 0x420C)
+#define IXGBE_KRM_AN_CNTL_1(P)		((P) ? 0x822C : 0x422C)
 #define IXGBE_KRM_DSP_TXFFE_STATE_4(P)	((P) ? 0x8634 : 0x4634)
 #define IXGBE_KRM_DSP_TXFFE_STATE_5(P)	((P) ? 0x8638 : 0x4638)
 #define IXGBE_KRM_RX_TRN_LINKUP_CTRL(P)	((P) ? 0x8B00 : 0x4B00)
@@ -3547,6 +3549,9 @@ struct ixgbe_info {
 #define IXGBE_KRM_LINK_CTRL_1_TETH_AN_ENABLE		(1 << 29)
 #define IXGBE_KRM_LINK_CTRL_1_TETH_AN_RESTART		(1 << 31)
 
+#define IXGBE_KRM_AN_CNTL_1_SYM_PAUSE			(1 << 28)
+#define IXGBE_KRM_AN_CNTL_1_ASM_PAUSE			(1 << 29)
+
 #define IXGBE_KRM_DSP_TXFFE_STATE_C0_EN			(1 << 6)
 #define IXGBE_KRM_DSP_TXFFE_STATE_CP1_CN1_EN		(1 << 15)
 #define IXGBE_KRM_DSP_TXFFE_STATE_CO_ADAPT_EN		(1 << 16)

drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c

@@ -846,6 +846,7 @@ static const struct ixgbe_mac_operations mac_ops_X540 = {
 	.clear_vfta             = &ixgbe_clear_vfta_generic,
 	.set_vfta               = &ixgbe_set_vfta_generic,
 	.fc_enable              = &ixgbe_fc_enable_generic,
+	.setup_fc		= ixgbe_setup_fc_generic,
 	.set_fw_drv_ver         = &ixgbe_set_fw_drv_ver_generic,
 	.init_uta_tables        = &ixgbe_init_uta_tables_generic,
 	.setup_sfp              = NULL,

drivers/net/ethernet/intel/ixgbe/ixgbe_x550.c

@@ -27,6 +27,7 @@
 #include "ixgbe_phy.h"
 
 static s32 ixgbe_setup_kr_speed_x550em(struct ixgbe_hw *, ixgbe_link_speed);
+static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *);
 
 static s32 ixgbe_get_invariants_X550_x(struct ixgbe_hw *hw)
 {
@@ -1342,15 +1343,18 @@ static void ixgbe_init_mac_link_ops_X550em(struct ixgbe_hw *hw)
 		mac->ops.enable_tx_laser = NULL;
 		mac->ops.flap_tx_laser = NULL;
 		mac->ops.setup_link = ixgbe_setup_mac_link_multispeed_fiber;
+		mac->ops.setup_fc = ixgbe_setup_fc_x550em;
 		mac->ops.setup_mac_link = ixgbe_setup_mac_link_sfp_x550em;
 		mac->ops.set_rate_select_speed =
 					ixgbe_set_soft_rate_select_speed;
 		break;
 	case ixgbe_media_type_copper:
 		mac->ops.setup_link = ixgbe_setup_mac_link_t_X550em;
+		mac->ops.setup_fc = ixgbe_setup_fc_generic;
 		mac->ops.check_link = ixgbe_check_link_t_X550em;
 		break;
 	default:
+		mac->ops.setup_fc = ixgbe_setup_fc_x550em;
 		break;
 	}
 }
@@ -1842,6 +1846,82 @@ static s32 ixgbe_get_lcd_t_x550em(struct ixgbe_hw *hw,
 	return status;
 }
 
+/**
+ * ixgbe_setup_fc_x550em - Set up flow control
+ * @hw: pointer to hardware structure
+ */
+static s32 ixgbe_setup_fc_x550em(struct ixgbe_hw *hw)
+{
+	bool pause, asm_dir;
+	u32 reg_val;
+	s32 rc;
+
+	/* 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;
+	}
+
+	/* 10gig parts do not have a word in the EEPROM to determine the
+	 * default flow control setting, so we explicitly set it to full.
+	 */
+	if (hw->fc.requested_mode == ixgbe_fc_default)
+		hw->fc.requested_mode = ixgbe_fc_full;
+
+	/* Determine PAUSE and ASM_DIR bits. */
+	switch (hw->fc.requested_mode) {
+	case ixgbe_fc_none:
+		pause = false;
+		asm_dir = false;
+		break;
+	case ixgbe_fc_tx_pause:
+		pause = false;
+		asm_dir = true;
+		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.
+		 */
+		/* Fallthrough */
+	case ixgbe_fc_full:
+		pause = true;
+		asm_dir = true;
+		break;
+	default:
+		hw_err(hw, "Flow control param set incorrectly\n");
+		return IXGBE_ERR_CONFIG;
+	}
+
+	if (hw->device_id != IXGBE_DEV_ID_X550EM_X_KR)
+		return 0;
+
+	rc = ixgbe_read_iosf_sb_reg_x550(hw,
+					 IXGBE_KRM_AN_CNTL_1(hw->bus.lan_id),
+					 IXGBE_SB_IOSF_TARGET_KR_PHY, &reg_val);
+	if (rc)
+		return rc;
+
+	reg_val &= ~(IXGBE_KRM_AN_CNTL_1_SYM_PAUSE |
+		     IXGBE_KRM_AN_CNTL_1_ASM_PAUSE);
+	if (pause)
+		reg_val |= IXGBE_KRM_AN_CNTL_1_SYM_PAUSE;
+	if (asm_dir)
+		reg_val |= IXGBE_KRM_AN_CNTL_1_ASM_PAUSE;
+	rc = ixgbe_write_iosf_sb_reg_x550(hw,
+					  IXGBE_KRM_AN_CNTL_1(hw->bus.lan_id),
+					  IXGBE_SB_IOSF_TARGET_KR_PHY, reg_val);
+
+	/* This device does not fully support AN. */
+	hw->fc.disable_fc_autoneg = true;
+
+	return rc;
+}
+
 /** ixgbe_enter_lplu_x550em - Transition to low power states
  *  @hw: pointer to hardware structure
  *
@@ -2337,8 +2417,6 @@ static void ixgbe_release_swfw_sync_X550em(struct ixgbe_hw *hw, u32 mask)
 	.enable_rx_buff			= &ixgbe_enable_rx_buff_generic, \
 	.get_thermal_sensor_data	= NULL, \
 	.init_thermal_sensor_thresh	= NULL, \
-	.prot_autoc_read		= &prot_autoc_read_generic, \
-	.prot_autoc_write		= &prot_autoc_write_generic, \
 	.enable_rx			= &ixgbe_enable_rx_generic, \
 	.disable_rx			= &ixgbe_disable_rx_x550, \
 
@@ -2354,6 +2432,9 @@ static const struct ixgbe_mac_operations mac_ops_X550 = {
 	.setup_sfp		= NULL,
 	.acquire_swfw_sync	= &ixgbe_acquire_swfw_sync_X540,
 	.release_swfw_sync	= &ixgbe_release_swfw_sync_X540,
+	.prot_autoc_read	= prot_autoc_read_generic,
+	.prot_autoc_write	= prot_autoc_write_generic,
+	.setup_fc		= ixgbe_setup_fc_generic,
 };
 
 static const struct ixgbe_mac_operations mac_ops_X550EM_x = {
@@ -2368,6 +2449,7 @@ static const struct ixgbe_mac_operations mac_ops_X550EM_x = {
 	.setup_sfp		= ixgbe_setup_sfp_modules_X550em,
 	.acquire_swfw_sync	= &ixgbe_acquire_swfw_sync_X550em,
 	.release_swfw_sync	= &ixgbe_release_swfw_sync_X550em,
+	.setup_fc		= NULL, /* defined later */
 };
 
 #define X550_COMMON_EEP \