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>

drivers/net/ethernet/intel/ice/ice_adminq_cmd.h

@@ -1461,6 +1461,55 @@ struct ice_aqc_get_sensor_reading_resp {
 	} data;
 };
 
+/* DNL call command (indirect 0x0682)
+ * Struct is used for both command and response
+ */
+struct ice_aqc_dnl_call_command {
+	u8 ctx; /* Used in command, reserved in response */
+	u8 reserved;
+	__le16 activity_id;
+#define ICE_AQC_ACT_ID_DNL 0x1129
+	__le32 reserved1;
+	__le32 addr_high;
+	__le32 addr_low;
+};
+
+struct ice_aqc_dnl_equa_param {
+	__le16 data_in;
+#define ICE_AQC_RX_EQU_SHIFT 8
+#define ICE_AQC_RX_EQU_PRE2 (0x10 << ICE_AQC_RX_EQU_SHIFT)
+#define ICE_AQC_RX_EQU_PRE1 (0x11 << ICE_AQC_RX_EQU_SHIFT)
+#define ICE_AQC_RX_EQU_POST1 (0x12 << ICE_AQC_RX_EQU_SHIFT)
+#define ICE_AQC_RX_EQU_BFLF (0x13 << ICE_AQC_RX_EQU_SHIFT)
+#define ICE_AQC_RX_EQU_BFHF (0x14 << ICE_AQC_RX_EQU_SHIFT)
+#define ICE_AQC_RX_EQU_DRATE (0x15 << ICE_AQC_RX_EQU_SHIFT)
+#define ICE_AQC_TX_EQU_PRE1 0x0
+#define ICE_AQC_TX_EQU_PRE3 0x3
+#define ICE_AQC_TX_EQU_ATTEN 0x4
+#define ICE_AQC_TX_EQU_POST1 0x8
+#define ICE_AQC_TX_EQU_PRE2 0xC
+	__le16 op_code_serdes_sel;
+#define ICE_AQC_OP_CODE_SHIFT 4
+#define ICE_AQC_OP_CODE_RX_EQU (0x9 << ICE_AQC_OP_CODE_SHIFT)
+#define ICE_AQC_OP_CODE_TX_EQU (0x10 << ICE_AQC_OP_CODE_SHIFT)
+	__le32 reserved[3];
+};
+
+struct ice_aqc_dnl_equa_respon {
+	/* Equalization value can be negative */
+	int val;
+	__le32 reserved[3];
+};
+
+/* DNL call command/response buffer (indirect 0x0682) */
+struct ice_aqc_dnl_call {
+	union {
+		struct ice_aqc_dnl_equa_param txrx_equa_reqs;
+		__le32 stores[4];
+		struct ice_aqc_dnl_equa_respon txrx_equa_resp;
+	} sto;
+};
+
 struct ice_aqc_link_topo_params {
 	u8 lport_num;
 	u8 lport_num_valid;
@@ -2564,6 +2613,7 @@ struct ice_aq_desc {
 		struct ice_aqc_get_link_status get_link_status;
 		struct ice_aqc_event_lan_overflow lan_overflow;
 		struct ice_aqc_get_link_topo get_link_topo;
+		struct ice_aqc_dnl_call_command dnl_call;
 		struct ice_aqc_i2c read_write_i2c;
 		struct ice_aqc_read_i2c_resp read_i2c_resp;
 		struct ice_aqc_get_set_tx_topo get_set_tx_topo;
@@ -2688,6 +2738,7 @@ enum ice_adminq_opc {
 	ice_aqc_opc_set_phy_rec_clk_out			= 0x0630,
 	ice_aqc_opc_get_phy_rec_clk_out			= 0x0631,
 	ice_aqc_opc_get_sensor_reading			= 0x0632,
+	ice_aqc_opc_dnl_call                            = 0x0682,
 	ice_aqc_opc_get_link_topo			= 0x06E0,
 	ice_aqc_opc_read_i2c				= 0x06E2,
 	ice_aqc_opc_write_i2c				= 0x06E3,

drivers/net/ethernet/intel/ice/ice_common.c

@@ -3371,6 +3371,43 @@ int ice_update_link_info(struct ice_port_info *pi)
 	return status;
 }
 
+/**
+ * ice_aq_get_phy_equalization - function to read serdes equaliser
+ * value from firmware using admin queue command.
+ * @hw: pointer to the HW struct
+ * @data_in: represents the serdes equalization parameter requested
+ * @op_code: represents the serdes number and flag to represent tx or rx
+ * @serdes_num: represents the serdes number
+ * @output: pointer to the caller-supplied buffer to return serdes equaliser
+ *
+ * Return: non-zero status on error and 0 on success.
+ */
+int ice_aq_get_phy_equalization(struct ice_hw *hw, u16 data_in, u16 op_code,
+				u8 serdes_num, int *output)
+{
+	struct ice_aqc_dnl_call_command *cmd;
+	struct ice_aqc_dnl_call buf = {};
+	struct ice_aq_desc desc;
+	int err;
+
+	buf.sto.txrx_equa_reqs.data_in = cpu_to_le16(data_in);
+	buf.sto.txrx_equa_reqs.op_code_serdes_sel =
+		cpu_to_le16(op_code | (serdes_num & 0xF));
+	cmd = &desc.params.dnl_call;
+	ice_fill_dflt_direct_cmd_desc(&desc, ice_aqc_opc_dnl_call);
+	desc.flags |= cpu_to_le16(ICE_AQ_FLAG_BUF |
+				  ICE_AQ_FLAG_RD |
+				  ICE_AQ_FLAG_SI);
+	desc.datalen = cpu_to_le16(sizeof(struct ice_aqc_dnl_call));
+	cmd->activity_id = cpu_to_le16(ICE_AQC_ACT_ID_DNL);
+
+	err = ice_aq_send_cmd(hw, &desc, &buf, sizeof(struct ice_aqc_dnl_call),
+			      NULL);
+	*output = err ? 0 : buf.sto.txrx_equa_resp.val;
+
+	return err;
+}
+
 #define FEC_REG_PORT(port) {	\
 	FEC_CORR_LOW_REG_PORT##port,		\
 	FEC_CORR_HIGH_REG_PORT##port,	\

drivers/net/ethernet/intel/ice/ice_common.h

@@ -142,6 +142,8 @@ int
 ice_get_link_default_override(struct ice_link_default_override_tlv *ldo,
 			      struct ice_port_info *pi);
 bool ice_is_phy_caps_an_enabled(struct ice_aqc_get_phy_caps_data *caps);
+int ice_aq_get_phy_equalization(struct ice_hw *hw, u16 data_in, u16 op_code,
+				u8 serdes_num, int *output);
 int
 ice_aq_get_fec_stats(struct ice_hw *hw, u16 pcs_quad, u16 pcs_port,
 		     enum ice_fec_stats_types fec_type, u32 *output);

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)

drivers/net/ethernet/intel/ice/ice_ethtool.h

@@ -9,6 +9,25 @@ struct ice_phy_type_to_ethtool {
 	u8 link_mode;
 };
 
+struct ice_serdes_equalization_to_ethtool {
+	int rx_equalization_pre2;
+	int rx_equalization_pre1;
+	int rx_equalization_post1;
+	int rx_equalization_bflf;
+	int rx_equalization_bfhf;
+	int rx_equalization_drate;
+	int tx_equalization_pre1;
+	int tx_equalization_pre3;
+	int tx_equalization_atten;
+	int tx_equalization_post1;
+	int tx_equalization_pre2;
+};
+
+struct ice_regdump_to_ethtool {
+	/* A multilane port can have max 4 serdes */
+	struct ice_serdes_equalization_to_ethtool equalization[4];
+};
+
 /* Port topology from lport i.e.
  * serdes mapping, pcsquad, macport, cage etc...
  */