ice: Implement driver functionality to dump serdes equalizer values

To debug link issues in the field, serdes Tx/Rx equalizer values
help to determine the health of serdes lane.

Extend 'ethtool -d' option to dump serdes Tx/Rx equalizer.
The following list of equalizer param is supported
    a. rx_equalization_pre2
    b. rx_equalization_pre1
    c. rx_equalization_post1
    d. rx_equalization_bflf
    e. rx_equalization_bfhf
    f. rx_equalization_drate
    g. tx_equalization_pre1
    h. tx_equalization_pre3
    i. tx_equalization_atten
    j. tx_equalization_post1
    k. tx_equalization_pre2

Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Anil Samal <anil.samal@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20240709202951.2103115-4-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 136 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index cb3fff0ff0b8..2b4f6f07737c 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -463,7 +463,8 @@ ice_get_drvinfo(struct net_device *netdev, struct ethtool_drvinfo *drvinfo)
 
 static int ice_get_regs_len(struct net_device __always_unused *netdev)
 {
-	return sizeof(ice_regs_dump_list);
+	return (sizeof(ice_regs_dump_list) +
+		sizeof(struct ice_regdump_to_ethtool));
 }
 
 /**
@@ -681,6 +682,137 @@ static int ice_get_port_topology(struct ice_hw *hw, u8 lport,
 	return 0;
 }
 
+/**
+ * ice_get_tx_rx_equa - read serdes tx rx equaliser param
+ * @hw: pointer to the HW struct
+ * @serdes_num: represents the serdes number
+ * @ptr: structure to read all serdes parameter for given serdes
+ *
+ * Return: all serdes equalization parameter supported per serdes number
+ */
+static int ice_get_tx_rx_equa(struct ice_hw *hw, u8 serdes_num,
+			      struct ice_serdes_equalization_to_ethtool *ptr)
+{
+	int err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_TX_EQU_PRE1,
+					  ICE_AQC_OP_CODE_TX_EQU, serdes_num,
+					  &ptr->tx_equalization_pre1);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_TX_EQU_PRE3,
+					  ICE_AQC_OP_CODE_TX_EQU, serdes_num,
+					  &ptr->tx_equalization_pre3);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_TX_EQU_ATTEN,
+					  ICE_AQC_OP_CODE_TX_EQU, serdes_num,
+					  &ptr->tx_equalization_atten);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_TX_EQU_POST1,
+					  ICE_AQC_OP_CODE_TX_EQU, serdes_num,
+					  &ptr->tx_equalization_post1);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_TX_EQU_PRE2,
+					  ICE_AQC_OP_CODE_TX_EQU, serdes_num,
+					  &ptr->tx_equalization_pre2);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_RX_EQU_PRE2,
+					  ICE_AQC_OP_CODE_RX_EQU, serdes_num,
+					  &ptr->rx_equalization_pre2);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_RX_EQU_PRE1,
+					  ICE_AQC_OP_CODE_RX_EQU, serdes_num,
+					  &ptr->rx_equalization_pre1);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_RX_EQU_POST1,
+					  ICE_AQC_OP_CODE_RX_EQU, serdes_num,
+					  &ptr->rx_equalization_post1);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_RX_EQU_BFLF,
+					  ICE_AQC_OP_CODE_RX_EQU, serdes_num,
+					  &ptr->rx_equalization_bflf);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_RX_EQU_BFHF,
+					  ICE_AQC_OP_CODE_RX_EQU, serdes_num,
+					  &ptr->rx_equalization_bfhf);
+	if (err)
+		return err;
+
+	err = ice_aq_get_phy_equalization(hw, ICE_AQC_RX_EQU_DRATE,
+					  ICE_AQC_OP_CODE_RX_EQU, serdes_num,
+					  &ptr->rx_equalization_drate);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/**
+ * ice_get_extended_regs - returns FEC correctable, uncorrectable stats per
+ *                         pcsquad, pcsport
+ * @netdev: pointer to net device structure
+ * @p: output buffer to fill requested register dump
+ *
+ * Return: 0 on success, negative on failure.
+ */
+static int ice_get_extended_regs(struct net_device *netdev, void *p)
+{
+	struct ice_netdev_priv *np = netdev_priv(netdev);
+	struct ice_regdump_to_ethtool *ice_prv_regs_buf;
+	struct ice_port_topology port_topology = {};
+	struct ice_port_info *pi;
+	struct ice_pf *pf;
+	struct ice_hw *hw;
+	unsigned int i;
+	int err;
+
+	pf = np->vsi->back;
+	hw = &pf->hw;
+	pi = np->vsi->port_info;
+
+	/* Serdes parameters are not supported if not the PF VSI */
+	if (np->vsi->type != ICE_VSI_PF || !pi)
+		return -EINVAL;
+
+	err = ice_get_port_topology(hw, pi->lport, &port_topology);
+	if (err)
+		return -EINVAL;
+	if (port_topology.serdes_lane_count > 4)
+		return -EINVAL;
+
+	ice_prv_regs_buf = p;
+
+	/* Get serdes equalization parameter for available serdes */
+	for (i = 0; i < port_topology.serdes_lane_count; i++) {
+		u8 serdes_num = 0;
+
+		serdes_num = port_topology.primary_serdes_lane + i;
+		err = ice_get_tx_rx_equa(hw, serdes_num,
+					 &ice_prv_regs_buf->equalization[i]);
+		if (err)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
 static void
 ice_get_regs(struct net_device *netdev, struct ethtool_regs *regs, void *p)
 {
@@ -690,10 +822,12 @@ ice_get_regs(struct net_device *netdev, struct ethtool_regs *regs, void *p)
 	u32 *regs_buf = (u32 *)p;
 	unsigned int i;
 
-	regs->version = 1;
+	regs->version = 2;
 
 	for (i = 0; i < ARRAY_SIZE(ice_regs_dump_list); ++i)
 		regs_buf[i] = rd32(hw, ice_regs_dump_list[i]);
+
+	ice_get_extended_regs(netdev, (void *)&regs_buf[i]);
 }
 
 static u32 ice_get_msglevel(struct net_device *netdev)