ixgbe: Fix 1G and 10G link stability for X550EM_x SFP+

Configures the CS4227 correctly for both 1G and 10G operation,
by moving the code to ixgbe_setup_mac_link_sfp_x550em(). It
needs to be in this function because we need both the module
type and the speed, and this is the only function in the init
flow that knows the speed. In contrast,
ixgbe_setup_sfp_modules_X550em() does not know the speed, so we
can't do anything useful here. This is a fundamental difference
from the previous flow, and is due to the way the CS4227 is
implemented.

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_phy.h

@@ -81,7 +81,12 @@
 #define IXGBE_I2C_EEPROM_STATUS_FAIL		0x2
 #define IXGBE_I2C_EEPROM_STATUS_IN_PROGRESS	0x3
 #define IXGBE_CS4227				0xBE    /* CS4227 address */
-#define IXGBE_CS4227_SPARE24_LSB		0x12B0  /* Reg to program EDC */
+#define IXGBE_CS4227_LINE_SPARE22_MSB		0x12AD	/* Reg to set speed */
+#define IXGBE_CS4227_LINE_SPARE24_LSB		0x12B0	/* Reg to set EDC */
+#define IXGBE_CS4227_HOST_SPARE22_MSB		0x1AAD	/* Reg to set speed */
+#define IXGBE_CS4227_HOST_SPARE24_LSB		0x1AB0	/* Reg to program EDC */
+#define IXGBE_CS4227_SPEED_1G			0x8000
+#define IXGBE_CS4227_SPEED_10G			0
 #define IXGBE_CS4227_EDC_MODE_CX1		0x0002
 #define IXGBE_CS4227_EDC_MODE_SR		0x0004
 

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

@@ -909,6 +909,40 @@ static s32 ixgbe_setup_ixfi_x550em(struct ixgbe_hw *hw, ixgbe_link_speed *speed)
 	return status;
 }
 
+/**
+ *  ixgbe_supported_sfp_modules_X550em - Check if SFP module type is supported
+ *  @hw: pointer to hardware structure
+ *  @linear: true if SFP module is linear
+ */
+static s32 ixgbe_supported_sfp_modules_X550em(struct ixgbe_hw *hw, bool *linear)
+{
+	switch (hw->phy.sfp_type) {
+	case ixgbe_sfp_type_not_present:
+		return IXGBE_ERR_SFP_NOT_PRESENT;
+	case ixgbe_sfp_type_da_cu_core0:
+	case ixgbe_sfp_type_da_cu_core1:
+		*linear = true;
+		break;
+	case ixgbe_sfp_type_srlr_core0:
+	case ixgbe_sfp_type_srlr_core1:
+	case ixgbe_sfp_type_da_act_lmt_core0:
+	case ixgbe_sfp_type_da_act_lmt_core1:
+	case ixgbe_sfp_type_1g_sx_core0:
+	case ixgbe_sfp_type_1g_sx_core1:
+	case ixgbe_sfp_type_1g_lx_core0:
+	case ixgbe_sfp_type_1g_lx_core1:
+		*linear = false;
+		break;
+	case ixgbe_sfp_type_unknown:
+	case ixgbe_sfp_type_1g_cu_core0:
+	case ixgbe_sfp_type_1g_cu_core1:
+	default:
+		return IXGBE_ERR_SFP_NOT_SUPPORTED;
+	}
+
+	return 0;
+}
+
 /**
  *  ixgbe_setup_mac_link_sfp_x550em - Configure the KR PHY for SFP.
  *  @hw: pointer to hardware structure
@@ -920,7 +954,49 @@ ixgbe_setup_mac_link_sfp_x550em(struct ixgbe_hw *hw,
 				ixgbe_link_speed speed,
 				__always_unused bool autoneg_wait_to_complete)
 {
-	return ixgbe_setup_ixfi_x550em(hw, &speed);
+	s32 status;
+	u16 slice, value;
+	bool setup_linear = false;
+
+	/* Check if SFP module is supported and linear */
+	status = ixgbe_supported_sfp_modules_X550em(hw, &setup_linear);
+
+	/* If no SFP module present, then return success. Return success since
+	 * there is no reason to configure CS4227 and SFP not present error is
+	 * not accepted in the setup MAC link flow.
+	 */
+	if (status == IXGBE_ERR_SFP_NOT_PRESENT)
+		return 0;
+
+	if (status)
+		return status;
+
+	/* Configure CS4227 LINE side to 10G SR. */
+	slice = IXGBE_CS4227_LINE_SPARE22_MSB + (hw->bus.lan_id << 12);
+	value = IXGBE_CS4227_SPEED_10G;
+	status = ixgbe_write_i2c_combined_generic(hw, IXGBE_CS4227, slice,
+						  value);
+
+	/* Configure CS4227 for HOST connection rate then type. */
+	slice = IXGBE_CS4227_HOST_SPARE22_MSB + (hw->bus.lan_id << 12);
+	value = speed & IXGBE_LINK_SPEED_10GB_FULL ?
+		IXGBE_CS4227_SPEED_10G : IXGBE_CS4227_SPEED_1G;
+	status = ixgbe_write_i2c_combined_generic(hw, IXGBE_CS4227, slice,
+						  value);
+
+	slice = IXGBE_CS4227_HOST_SPARE24_LSB + (hw->bus.lan_id << 12);
+	if (setup_linear)
+		value = (IXGBE_CS4227_EDC_MODE_CX1 << 1) | 1;
+	else
+		value = (IXGBE_CS4227_EDC_MODE_SR << 1) | 1;
+	status = ixgbe_write_i2c_combined_generic(hw, IXGBE_CS4227, slice,
+						  value);
+
+	/* If internal link mode is XFI, then setup XFI internal link. */
+	if (!(hw->phy.nw_mng_if_sel & IXGBE_NW_MNG_IF_SEL_INT_PHY_MODE))
+		status = ixgbe_setup_ixfi_x550em(hw, &speed);
+
+	return status;
 }
 
 /**
@@ -1036,53 +1112,18 @@ static void ixgbe_init_mac_link_ops_X550em(struct ixgbe_hw *hw)
  */
 static s32 ixgbe_setup_sfp_modules_X550em(struct ixgbe_hw *hw)
 {
-	bool setup_linear;
-	u16 reg_slice, edc_mode;
-	s32 ret_val;
+	s32 status;
+	bool linear;
 
-	switch (hw->phy.sfp_type) {
-	case ixgbe_sfp_type_unknown:
-		return 0;
-	case ixgbe_sfp_type_not_present:
-		return IXGBE_ERR_SFP_NOT_PRESENT;
-	case ixgbe_sfp_type_da_cu_core0:
-	case ixgbe_sfp_type_da_cu_core1:
-		setup_linear = true;
-		break;
-	case ixgbe_sfp_type_srlr_core0:
-	case ixgbe_sfp_type_srlr_core1:
-	case ixgbe_sfp_type_da_act_lmt_core0:
-	case ixgbe_sfp_type_da_act_lmt_core1:
-	case ixgbe_sfp_type_1g_sx_core0:
-	case ixgbe_sfp_type_1g_sx_core1:
-		setup_linear = false;
-		break;
-	default:
-		return IXGBE_ERR_SFP_NOT_SUPPORTED;
-	}
+	/* Check if SFP module is supported */
+	status = ixgbe_supported_sfp_modules_X550em(hw, &linear);
+	if (status)
+		return status;
 
 	ixgbe_init_mac_link_ops_X550em(hw);
 	hw->phy.ops.reset = NULL;
 
-	/* The CS4227 slice address is the base address + the port-pair reg
-	 * offset. I.e. Slice 0 = 0x12B0 and slice 1 = 0x22B0.
-	 */
-	reg_slice = IXGBE_CS4227_SPARE24_LSB + (hw->bus.lan_id << 12);
-
-	if (setup_linear)
-		edc_mode = (IXGBE_CS4227_EDC_MODE_CX1 << 1) | 0x1;
-	else
-		edc_mode = (IXGBE_CS4227_EDC_MODE_SR << 1) | 0x1;
-
-	/* Configure CS4227 for connection type. */
-	ret_val = hw->phy.ops.write_i2c_combined(hw, IXGBE_CS4227, reg_slice,
-						 edc_mode);
-
-	if (ret_val)
-		ret_val = hw->phy.ops.write_i2c_combined(hw, 0x80, reg_slice,
-							 edc_mode);
-
-	return ret_val;
+	return 0;
 }
 
 /** ixgbe_get_link_capabilities_x550em - Determines link capabilities