diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_env.c b/drivers/net/ethernet/mellanox/mlxsw/core_env.c
index 29a74b8bd5b5..3103fef43955 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core_env.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_env.c
@@ -177,7 +177,7 @@ int mlxsw_env_module_temp_thresholds_get(struct mlxsw_core *core, int module,
 	int page;
 	int err;
 
-	mlxsw_reg_mtmp_pack(mtmp_pl, MLXSW_REG_MTMP_MODULE_INDEX_MIN + module,
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0, MLXSW_REG_MTMP_MODULE_INDEX_MIN + module,
 			    false, false);
 	err = mlxsw_reg_query(core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c b/drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c
index 8b170ad92302..71ca3b561e62 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c
@@ -66,7 +66,7 @@ static ssize_t mlxsw_hwmon_temp_show(struct device *dev,
 
 	index = mlxsw_hwmon_get_attr_index(mlxsw_hwmon_attr->type_index,
 					   mlxsw_hwmon->module_sensor_max);
-	mlxsw_reg_mtmp_pack(mtmp_pl, index, false, false);
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0, index, false, false);
 	err = mlxsw_reg_query(mlxsw_hwmon->core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err) {
 		dev_err(mlxsw_hwmon->bus_info->dev, "Failed to query temp sensor\n");
@@ -89,7 +89,7 @@ static ssize_t mlxsw_hwmon_temp_max_show(struct device *dev,
 
 	index = mlxsw_hwmon_get_attr_index(mlxsw_hwmon_attr->type_index,
 					   mlxsw_hwmon->module_sensor_max);
-	mlxsw_reg_mtmp_pack(mtmp_pl, index, false, false);
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0, index, false, false);
 	err = mlxsw_reg_query(mlxsw_hwmon->core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err) {
 		dev_err(mlxsw_hwmon->bus_info->dev, "Failed to query temp sensor\n");
@@ -232,8 +232,9 @@ static int mlxsw_hwmon_module_temp_get(struct device *dev,
 	int err;
 
 	module = mlxsw_hwmon_attr->type_index - mlxsw_hwmon->sensor_count;
-	mlxsw_reg_mtmp_pack(mtmp_pl, MLXSW_REG_MTMP_MODULE_INDEX_MIN + module,
-			    false, false);
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0,
+			    MLXSW_REG_MTMP_MODULE_INDEX_MIN + module, false,
+			    false);
 	err = mlxsw_reg_query(mlxsw_hwmon->core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err) {
 		dev_err(dev, "Failed to query module temperature\n");
@@ -721,7 +722,7 @@ static int mlxsw_hwmon_gearbox_init(struct mlxsw_hwmon *mlxsw_hwmon)
 	while (index < max_index) {
 		sensor_index = index % mlxsw_hwmon->module_sensor_max +
 			       MLXSW_REG_MTMP_GBOX_INDEX_MIN;
-		mlxsw_reg_mtmp_pack(mtmp_pl, sensor_index, true, true);
+		mlxsw_reg_mtmp_pack(mtmp_pl, 0, sensor_index, true, true);
 		err = mlxsw_reg_write(mlxsw_hwmon->core,
 				      MLXSW_REG(mtmp), mtmp_pl);
 		if (err) {
diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c b/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c
index 05f54bd982c0..65ab04e32972 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c
@@ -271,7 +271,7 @@ static int mlxsw_thermal_get_temp(struct thermal_zone_device *tzdev,
 	int temp;
 	int err;
 
-	mlxsw_reg_mtmp_pack(mtmp_pl, 0, false, false);
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0, 0, false, false);
 
 	err = mlxsw_reg_query(thermal->core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err) {
@@ -431,7 +431,7 @@ mlxsw_thermal_module_temp_and_thresholds_get(struct mlxsw_core *core,
 	int err;
 
 	/* Read module temperature and thresholds. */
-	mlxsw_reg_mtmp_pack(mtmp_pl, sensor_index, false, false);
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0, sensor_index, false, false);
 	err = mlxsw_reg_query(core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err) {
 		/* Set temperature and thresholds to zero to avoid passing
@@ -576,7 +576,7 @@ static int mlxsw_thermal_gearbox_temp_get(struct thermal_zone_device *tzdev,
 	int err;
 
 	index = MLXSW_REG_MTMP_GBOX_INDEX_MIN + tz->module;
-	mlxsw_reg_mtmp_pack(mtmp_pl, index, false, false);
+	mlxsw_reg_mtmp_pack(mtmp_pl, 0, index, false, false);
 
 	err = mlxsw_reg_query(thermal->core, MLXSW_REG(mtmp), mtmp_pl);
 	if (err)
diff --git a/drivers/net/ethernet/mellanox/mlxsw/reg.h b/drivers/net/ethernet/mellanox/mlxsw/reg.h
index 67b1a2f8397f..5de77d6e08ba 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/reg.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/reg.h
@@ -9721,6 +9721,12 @@ MLXSW_ITEM32(reg, mtcap, sensor_count, 0x00, 0, 7);
 
 MLXSW_REG_DEFINE(mtmp, MLXSW_REG_MTMP_ID, MLXSW_REG_MTMP_LEN);
 
+/* reg_mtmp_slot_index
+ * Slot index (0: Main board).
+ * Access: Index
+ */
+MLXSW_ITEM32(reg, mtmp, slot_index, 0x00, 16, 4);
+
 #define MLXSW_REG_MTMP_MODULE_INDEX_MIN 64
 #define MLXSW_REG_MTMP_GBOX_INDEX_MIN 256
 /* reg_mtmp_sensor_index
@@ -9810,11 +9816,12 @@ MLXSW_ITEM32(reg, mtmp, temperature_threshold_lo, 0x10, 0, 16);
  */
 MLXSW_ITEM_BUF(reg, mtmp, sensor_name, 0x18, MLXSW_REG_MTMP_SENSOR_NAME_SIZE);
 
-static inline void mlxsw_reg_mtmp_pack(char *payload, u16 sensor_index,
-				       bool max_temp_enable,
+static inline void mlxsw_reg_mtmp_pack(char *payload, u8 slot_index,
+				       u16 sensor_index, bool max_temp_enable,
 				       bool max_temp_reset)
 {
 	MLXSW_REG_ZERO(mtmp, payload);
+	mlxsw_reg_mtmp_slot_index_set(payload, slot_index);
 	mlxsw_reg_mtmp_sensor_index_set(payload, sensor_index);
 	mlxsw_reg_mtmp_mte_set(payload, max_temp_enable);
 	mlxsw_reg_mtmp_mtr_set(payload, max_temp_reset);