mlxsw: core: Add support for temperature thresholds reading for QSFP-DD transceivers

Allow QSFP-DD transceivers temperature thresholds reading for hardware
monitoring and thermal control.

For this type, the thresholds are located in page 02h according to the
"Module and Lane Thresholds" description from Common Management
Interface Specification.
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/core_env.c

@@ -11,7 +11,7 @@
 #include "reg.h"
 
 static int mlxsw_env_validate_cable_ident(struct mlxsw_core *core, int id,
-					  bool *qsfp)
+					  bool *qsfp, bool *cmis)
 {
 	char eeprom_tmp[MLXSW_REG_MCIA_EEPROM_SIZE];
 	char mcia_pl[MLXSW_REG_MCIA_LEN];
@@ -25,15 +25,19 @@ static int mlxsw_env_validate_cable_ident(struct mlxsw_core *core, int id,
 		return err;
 	mlxsw_reg_mcia_eeprom_memcpy_from(mcia_pl, eeprom_tmp);
 	ident = eeprom_tmp[0];
+	*cmis = false;
 	switch (ident) {
 	case MLXSW_REG_MCIA_EEPROM_MODULE_INFO_ID_SFP:
 		*qsfp = false;
 		break;
 	case MLXSW_REG_MCIA_EEPROM_MODULE_INFO_ID_QSFP: /* fall-through */
 	case MLXSW_REG_MCIA_EEPROM_MODULE_INFO_ID_QSFP_PLUS: /* fall-through */
-	case MLXSW_REG_MCIA_EEPROM_MODULE_INFO_ID_QSFP28: /* fall-through */
+	case MLXSW_REG_MCIA_EEPROM_MODULE_INFO_ID_QSFP28:
+		*qsfp = true;
+		break;
 	case MLXSW_REG_MCIA_EEPROM_MODULE_INFO_ID_QSFP_DD:
 		*qsfp = true;
+		*cmis = true;
 		break;
 	default:
 		return -EINVAL;
@@ -117,7 +121,8 @@ int mlxsw_env_module_temp_thresholds_get(struct mlxsw_core *core, int module,
 	char mcia_pl[MLXSW_REG_MCIA_LEN] = {0};
 	char mtmp_pl[MLXSW_REG_MTMP_LEN];
 	unsigned int module_temp;
-	bool qsfp;
+	bool qsfp, cmis;
+	int page;
 	int err;
 
 	mlxsw_reg_mtmp_pack(mtmp_pl, MLXSW_REG_MTMP_MODULE_INDEX_MIN + module,
@@ -141,21 +146,28 @@ int mlxsw_env_module_temp_thresholds_get(struct mlxsw_core *core, int module,
 	 */
 
 	/* Validate module identifier value. */
-	err = mlxsw_env_validate_cable_ident(core, module, &qsfp);
+	err = mlxsw_env_validate_cable_ident(core, module, &qsfp, &cmis);
 	if (err)
 		return err;
 
-	if (qsfp)
-		mlxsw_reg_mcia_pack(mcia_pl, module, 0,
-				    MLXSW_REG_MCIA_TH_PAGE_NUM,
+	if (qsfp) {
+		/* For QSFP/CMIS module-defined thresholds are located in page
+		 * 02h, otherwise in page 03h.
+		 */
+		if (cmis)
+			page = MLXSW_REG_MCIA_TH_PAGE_CMIS_NUM;
+		else
+			page = MLXSW_REG_MCIA_TH_PAGE_NUM;
+		mlxsw_reg_mcia_pack(mcia_pl, module, 0, page,
 				    MLXSW_REG_MCIA_TH_PAGE_OFF + off,
 				    MLXSW_REG_MCIA_TH_ITEM_SIZE,
 				    MLXSW_REG_MCIA_I2C_ADDR_LOW);
-	else
+	} else {
 		mlxsw_reg_mcia_pack(mcia_pl, module, 0,
 				    MLXSW_REG_MCIA_PAGE0_LO,
 				    off, MLXSW_REG_MCIA_TH_ITEM_SIZE,
 				    MLXSW_REG_MCIA_I2C_ADDR_HIGH);
+	}
 
 	err = mlxsw_reg_query(core, MLXSW_REG(mcia), mcia_pl);
 	if (err)
@@ -252,8 +264,8 @@ int mlxsw_env_get_module_eeprom(struct net_device *netdev,
 {
 	int offset = ee->offset;
 	unsigned int read_size;
+	bool qsfp, cmis;
 	int i = 0;
-	bool qsfp;
 	int err;
 
 	if (!ee->len)
@@ -261,7 +273,7 @@ int mlxsw_env_get_module_eeprom(struct net_device *netdev,
 
 	memset(data, 0, ee->len);
 	/* Validate module identifier value. */
-	err = mlxsw_env_validate_cable_ident(mlxsw_core, module, &qsfp);
+	err = mlxsw_env_validate_cable_ident(mlxsw_core, module, &qsfp, &cmis);
 	if (err)
 		return err;
 

drivers/net/ethernet/mellanox/mlxsw/reg.h

@@ -8605,6 +8605,7 @@ MLXSW_ITEM32(reg, mcia, size, 0x08, 0, 16);
 #define MLXSW_REG_MCIA_PAGE0_LO_OFF		0xa0
 #define MLXSW_REG_MCIA_TH_ITEM_SIZE		2
 #define MLXSW_REG_MCIA_TH_PAGE_NUM		3
+#define MLXSW_REG_MCIA_TH_PAGE_CMIS_NUM		2
 #define MLXSW_REG_MCIA_PAGE0_LO			0
 #define MLXSW_REG_MCIA_TH_PAGE_OFF		0x80
 #define MLXSW_REG_MCIA_EEPROM_CMIS_FLAT_MEMORY	BIT(7)