net: dsa: vsc73xx: implement FDB operations

This commit introduces implementations of three functions:
.port_fdb_dump
.port_fdb_add
.port_fdb_del

The FDB database organization is the same as in other old Vitesse chips:
It has 2048 rows and 4 columns (buckets). The row index is calculated by
the hash function 'vsc73xx_calc_hash' and the FDB entry must be placed
exactly into row[hash]. The chip selects the bucket number by itself.

Signed-off-by: Pawel Dembicki <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Paolo Abeni <[e-mail]>

drivers/net/dsa/vitesse-vsc73xx-core.c

···
 #define VSC73XX_BLOCK_MII_EXTERNAL	0x1 /* External MDIO subblock */
 
 #define CPU_PORT	6 /* CPU port */
+#define VSC73XX_NUM_FDB_ROWS	2048
+#define VSC73XX_NUM_BUCKETS	4
 
 /* MAC Block registers */
 #define VSC73XX_MAC_CFG		0x00
···
 #define VSC73XX_SRCMASKS_MIRROR			BIT(26)
 #define VSC73XX_SRCMASKS_PORTS_MASK		GENMASK(7, 0)
 
+#define VSC73XX_MACHDATA_VID			GENMASK(27, 16)
+#define VSC73XX_MACHDATA_MAC0			GENMASK(15, 8)
+#define VSC73XX_MACHDATA_MAC1			GENMASK(7, 0)
+#define VSC73XX_MACLDATA_MAC2			GENMASK(31, 24)
+#define VSC73XX_MACLDATA_MAC3			GENMASK(23, 16)
+#define VSC73XX_MACLDATA_MAC4			GENMASK(15, 8)
+#define VSC73XX_MACLDATA_MAC5			GENMASK(7, 0)
+
+#define VSC73XX_HASH0_VID_FROM_MASK		GENMASK(5, 0)
+#define VSC73XX_HASH0_MAC0_FROM_MASK		GENMASK(7, 4)
+#define VSC73XX_HASH1_MAC0_FROM_MASK		GENMASK(3, 0)
+#define VSC73XX_HASH1_MAC1_FROM_MASK		GENMASK(7, 1)
+#define VSC73XX_HASH2_MAC1_FROM_MASK		BIT(0)
+#define VSC73XX_HASH2_MAC2_FROM_MASK		GENMASK(7, 0)
+#define VSC73XX_HASH2_MAC3_FROM_MASK		GENMASK(7, 6)
+#define VSC73XX_HASH3_MAC3_FROM_MASK		GENMASK(5, 0)
+#define VSC73XX_HASH3_MAC4_FROM_MASK		GENMASK(7, 3)
+#define VSC73XX_HASH4_MAC4_FROM_MASK		GENMASK(2, 0)
+
+#define VSC73XX_HASH0_VID_TO_MASK		GENMASK(9, 4)
+#define VSC73XX_HASH0_MAC0_TO_MASK		GENMASK(3, 0)
+#define VSC73XX_HASH1_MAC0_TO_MASK		GENMASK(10, 7)
+#define VSC73XX_HASH1_MAC1_TO_MASK		GENMASK(6, 0)
+#define VSC73XX_HASH2_MAC1_TO_MASK		BIT(10)
+#define VSC73XX_HASH2_MAC2_TO_MASK		GENMASK(9, 2)
+#define VSC73XX_HASH2_MAC3_TO_MASK		GENMASK(1, 0)
+#define VSC73XX_HASH3_MAC3_TO_MASK		GENMASK(10, 5)
+#define VSC73XX_HASH3_MAC4_TO_MASK		GENMASK(4, 0)
+#define VSC73XX_HASH4_MAC4_TO_MASK		GENMASK(10, 8)
+
+#define VSC73XX_MACTINDX_SHADOW			BIT(13)
+#define VSC73XX_MACTINDX_BUCKET_MSK		GENMASK(12, 11)
+#define VSC73XX_MACTINDX_INDEX_MSK		GENMASK(10, 0)
+
 #define VSC73XX_MACACCESS_CPU_COPY		BIT(14)
 #define VSC73XX_MACACCESS_FWD_KILL		BIT(13)
 #define VSC73XX_MACACCESS_IGNORE_VLAN		BIT(12)
···
 struct vsc73xx_counter {
 	u8 counter;
 	const char *name;
+};
+
+struct vsc73xx_fdb {
+	u16 vid;
+	u8 port;
+	u8 mac[ETH_ALEN];
+	bool valid;
 };
 
 /* Counters are named according to the MIB standards where applicable.
···
 
 	ds->untag_bridge_pvid = true;
 	ds->max_num_bridges = DSA_TAG_8021Q_MAX_NUM_BRIDGES;
+	ds->fdb_isolation = true;
 
 	/* Issue RESET */
 	vsc73xx_write(vsc, VSC73XX_BLOCK_SYSTEM, 0, VSC73XX_GLORESET,
···
 		vsc73xx_refresh_fwd_map(ds, port, state);
 }
 
+static u16 vsc73xx_calc_hash(const unsigned char *addr, u16 vid)
+{
+	/* VID 5-0, MAC 47-44 */
+	u16 hash = FIELD_PREP(VSC73XX_HASH0_VID_TO_MASK,
+			      FIELD_GET(VSC73XX_HASH0_VID_FROM_MASK, vid)) |
+		   FIELD_PREP(VSC73XX_HASH0_MAC0_TO_MASK,
+			      FIELD_GET(VSC73XX_HASH0_MAC0_FROM_MASK, addr[0]));
+	/* MAC 43-33 */
+	hash ^= FIELD_PREP(VSC73XX_HASH1_MAC0_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH1_MAC0_FROM_MASK, addr[0])) |
+		FIELD_PREP(VSC73XX_HASH1_MAC1_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH1_MAC1_FROM_MASK, addr[1]));
+	/* MAC 32-22 */
+	hash ^= FIELD_PREP(VSC73XX_HASH2_MAC1_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH2_MAC1_FROM_MASK, addr[1])) |
+		FIELD_PREP(VSC73XX_HASH2_MAC2_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH2_MAC2_FROM_MASK, addr[2])) |
+		FIELD_PREP(VSC73XX_HASH2_MAC3_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH2_MAC3_FROM_MASK, addr[3]));
+	/* MAC 21-11 */
+	hash ^= FIELD_PREP(VSC73XX_HASH3_MAC3_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH3_MAC3_FROM_MASK, addr[3])) |
+		FIELD_PREP(VSC73XX_HASH3_MAC4_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH3_MAC4_FROM_MASK, addr[4]));
+	/* MAC 10-0 */
+	hash ^= FIELD_PREP(VSC73XX_HASH4_MAC4_TO_MASK,
+			   FIELD_GET(VSC73XX_HASH4_MAC4_FROM_MASK, addr[4])) |
+		addr[5];
+
+	return hash;
+}
+
+static int
+vsc73xx_port_wait_for_mac_table_cmd(struct vsc73xx *vsc)
+{
+	int ret, err;
+	u32 val;
+
+	ret = read_poll_timeout(vsc73xx_read, err,
+				err < 0 ||
+				((val & VSC73XX_MACACCESS_CMD_MASK) ==
+				 VSC73XX_MACACCESS_CMD_IDLE),
+				VSC73XX_POLL_SLEEP_US, VSC73XX_POLL_TIMEOUT_US,
+				false, vsc, VSC73XX_BLOCK_ANALYZER,
+				0, VSC73XX_MACACCESS, &val);
+	if (ret)
+		return ret;
+	return err;
+}
+
+static int vsc73xx_port_read_mac_table_row(struct vsc73xx *vsc, u16 index,
+					   struct vsc73xx_fdb *fdb)
+{
+	int ret, i;
+	u32 val;
+
+	if (!fdb)
+		return -EINVAL;
+	if (index >= VSC73XX_NUM_FDB_ROWS)
+		return -EINVAL;
+
+	for (i = 0; i < VSC73XX_NUM_BUCKETS; i++) {
+		ret = vsc73xx_write(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+				    VSC73XX_MACTINDX,
+				    (i ? 0 : VSC73XX_MACTINDX_SHADOW) |
+				    FIELD_PREP(VSC73XX_MACTINDX_BUCKET_MSK, i) |
+				    index);
+		if (ret)
+			return ret;
+
+		ret = vsc73xx_port_wait_for_mac_table_cmd(vsc);
+		if (ret)
+			return ret;
+
+		ret = vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+					  VSC73XX_MACACCESS,
+					  VSC73XX_MACACCESS_CMD_MASK,
+					  VSC73XX_MACACCESS_CMD_READ_ENTRY);
+		if (ret)
+			return ret;
+
+		ret = vsc73xx_port_wait_for_mac_table_cmd(vsc);
+		if (ret)
+			return ret;
+
+		ret = vsc73xx_read(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+				   VSC73XX_MACACCESS, &val);
+		if (ret)
+			return ret;
+
+		fdb[i].valid = FIELD_GET(VSC73XX_MACACCESS_VALID, val);
+		if (!fdb[i].valid)
+			continue;
+
+		fdb[i].port = FIELD_GET(VSC73XX_MACACCESS_DEST_IDX_MASK, val);
+
+		ret = vsc73xx_read(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+				   VSC73XX_MACHDATA, &val);
+		if (ret)
+			return ret;
+
+		fdb[i].vid = FIELD_GET(VSC73XX_MACHDATA_VID, val);
+		fdb[i].mac[0] = FIELD_GET(VSC73XX_MACHDATA_MAC0, val);
+		fdb[i].mac[1] = FIELD_GET(VSC73XX_MACHDATA_MAC1, val);
+
+		ret = vsc73xx_read(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+				   VSC73XX_MACLDATA, &val);
+		if (ret)
+			return ret;
+
+		fdb[i].mac[2] = FIELD_GET(VSC73XX_MACLDATA_MAC2, val);
+		fdb[i].mac[3] = FIELD_GET(VSC73XX_MACLDATA_MAC3, val);
+		fdb[i].mac[4] = FIELD_GET(VSC73XX_MACLDATA_MAC4, val);
+		fdb[i].mac[5] = FIELD_GET(VSC73XX_MACLDATA_MAC5, val);
+	}
+
+	return ret;
+}
+
+static int
+vsc73xx_fdb_operation(struct vsc73xx *vsc, const unsigned char *addr, u16 vid,
+		      u16 hash, u16 cmd_mask, u16 cmd_val)
+{
+	int ret;
+	u32 val;
+
+	val = FIELD_PREP(VSC73XX_MACHDATA_VID, vid) |
+	      FIELD_PREP(VSC73XX_MACHDATA_MAC0, addr[0]) |
+	      FIELD_PREP(VSC73XX_MACHDATA_MAC1, addr[1]);
+	ret = vsc73xx_write(vsc, VSC73XX_BLOCK_ANALYZER, 0, VSC73XX_MACHDATA,
+			    val);
+	if (ret)
+		return ret;
+
+	val = FIELD_PREP(VSC73XX_MACLDATA_MAC2, addr[2]) |
+	      FIELD_PREP(VSC73XX_MACLDATA_MAC3, addr[3]) |
+	      FIELD_PREP(VSC73XX_MACLDATA_MAC4, addr[4]) |
+	      FIELD_PREP(VSC73XX_MACLDATA_MAC5, addr[5]);
+	ret = vsc73xx_write(vsc, VSC73XX_BLOCK_ANALYZER, 0, VSC73XX_MACLDATA,
+			    val);
+	if (ret)
+		return ret;
+
+	ret = vsc73xx_write(vsc, VSC73XX_BLOCK_ANALYZER, 0, VSC73XX_MACTINDX,
+			    hash);
+	if (ret)
+		return ret;
+
+	ret = vsc73xx_port_wait_for_mac_table_cmd(vsc);
+	if (ret)
+		return ret;
+
+	ret = vsc73xx_update_bits(vsc, VSC73XX_BLOCK_ANALYZER, 0,
+				  VSC73XX_MACACCESS, cmd_mask, cmd_val);
+	if (ret)
+		return ret;
+
+	return vsc73xx_port_wait_for_mac_table_cmd(vsc);
+}
+
+static int vsc73xx_fdb_del_entry(struct vsc73xx *vsc, int port,
+				 const unsigned char *addr, u16 vid)
+{
+	struct vsc73xx_fdb fdb[VSC73XX_NUM_BUCKETS];
+	u16 hash = vsc73xx_calc_hash(addr, vid);
+	int bucket, ret;
+
+	mutex_lock(&vsc->fdb_lock);
+
+	ret = vsc73xx_port_read_mac_table_row(vsc, hash, fdb);
+	if (ret)
+		goto err;
+
+	for (bucket = 0; bucket < VSC73XX_NUM_BUCKETS; bucket++) {
+		if (fdb[bucket].valid && fdb[bucket].port == port &&
+		    ether_addr_equal(addr, fdb[bucket].mac))
+			break;
+	}
+
+	if (bucket == VSC73XX_NUM_BUCKETS) {
+		/* Can't find MAC in MAC table */
+		ret = -ENODATA;
+		goto err;
+	}
+
+	ret = vsc73xx_fdb_operation(vsc, addr, vid, hash,
+				    VSC73XX_MACACCESS_CMD_MASK,
+				    VSC73XX_MACACCESS_CMD_FORGET);
+err:
+	mutex_unlock(&vsc->fdb_lock);
+	return ret;
+}
+
+static int vsc73xx_fdb_add_entry(struct vsc73xx *vsc, int port,
+				 const unsigned char *addr, u16 vid)
+{
+	struct vsc73xx_fdb fdb[VSC73XX_NUM_BUCKETS];
+	u16 hash = vsc73xx_calc_hash(addr, vid);
+	int bucket, ret;
+	u32 val;
+
+	mutex_lock(&vsc->fdb_lock);
+
+	ret = vsc73xx_port_read_mac_table_row(vsc, hash, fdb);
+	if (ret)
+		goto err;
+
+	for (bucket = 0; bucket < VSC73XX_NUM_BUCKETS; bucket++) {
+		if (!fdb[bucket].valid)
+			break;
+	}
+
+	if (bucket == VSC73XX_NUM_BUCKETS) {
+		/* Bucket is full */
+		ret = -EOVERFLOW;
+		goto err;
+	}
+
+	val = VSC73XX_MACACCESS_VALID | VSC73XX_MACACCESS_LOCKED |
+	      FIELD_PREP(VSC73XX_MACACCESS_DEST_IDX_MASK, port) |
+	      VSC73XX_MACACCESS_CMD_LEARN;
+	ret = vsc73xx_fdb_operation(vsc, addr, vid, hash,
+				    VSC73XX_MACACCESS_VALID |
+				    VSC73XX_MACACCESS_LOCKED |
+				    VSC73XX_MACACCESS_DEST_IDX_MASK |
+				    VSC73XX_MACACCESS_CMD_MASK, val);
+err:
+	mutex_unlock(&vsc->fdb_lock);
+	return ret;
+}
+
+static int vsc73xx_fdb_add(struct dsa_switch *ds, int port,
+			   const unsigned char *addr, u16 vid, struct dsa_db db)
+{
+	struct vsc73xx *vsc = ds->priv;
+
+	if (!vid) {
+		switch (db.type) {
+		case DSA_DB_PORT:
+			vid = dsa_tag_8021q_standalone_vid(db.dp);
+			break;
+		case DSA_DB_BRIDGE:
+			vid = dsa_tag_8021q_bridge_vid(db.bridge.num);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+	}
+
+	return vsc73xx_fdb_add_entry(vsc, port, addr, vid);
+}
+
+static int vsc73xx_fdb_del(struct dsa_switch *ds, int port,
+			   const unsigned char *addr, u16 vid, struct dsa_db db)
+{
+	struct vsc73xx *vsc = ds->priv;
+
+	if (!vid) {
+		switch (db.type) {
+		case DSA_DB_PORT:
+			vid = dsa_tag_8021q_standalone_vid(db.dp);
+			break;
+		case DSA_DB_BRIDGE:
+			vid = dsa_tag_8021q_bridge_vid(db.bridge.num);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+	}
+
+	return vsc73xx_fdb_del_entry(vsc, port, addr, vid);
+}
+
+static int vsc73xx_port_fdb_dump(struct dsa_switch *ds,
+				 int port, dsa_fdb_dump_cb_t *cb, void *data)
+{
+	struct vsc73xx_fdb fdb[VSC73XX_NUM_BUCKETS];
+	struct vsc73xx *vsc = ds->priv;
+	u16 i, bucket;
+	int err = 0;
+
+	mutex_lock(&vsc->fdb_lock);
+
+	for (i = 0; i < VSC73XX_NUM_FDB_ROWS; i++) {
+		err = vsc73xx_port_read_mac_table_row(vsc, i, fdb);
+		if (err)
+			goto unlock;
+
+		for (bucket = 0; bucket < VSC73XX_NUM_BUCKETS; bucket++) {
+			if (!fdb[bucket].valid || fdb[bucket].port != port)
+				continue;
+
+			/* We need to hide dsa_8021q VLANs from the user */
+			if (vid_is_dsa_8021q(fdb[bucket].vid))
+				fdb[bucket].vid = 0;
+
+			err = cb(fdb[bucket].mac, fdb[bucket].vid, false, data);
+			if (err)
+				goto unlock;
+		}
+	}
+unlock:
+	mutex_unlock(&vsc->fdb_lock);
+	return err;
+}
+
 static const struct phylink_mac_ops vsc73xx_phylink_mac_ops = {
 	.mac_config = vsc73xx_mac_config,
 	.mac_link_down = vsc73xx_mac_link_down,
···
 	.port_bridge_join = dsa_tag_8021q_bridge_join,
 	.port_bridge_leave = dsa_tag_8021q_bridge_leave,
 	.port_change_mtu = vsc73xx_change_mtu,
+	.port_fdb_add = vsc73xx_fdb_add,
+	.port_fdb_del = vsc73xx_fdb_del,
+	.port_fdb_dump = vsc73xx_port_fdb_dump,
 	.port_max_mtu = vsc73xx_get_max_mtu,
 	.port_stp_state_set = vsc73xx_port_stp_state_set,
 	.port_vlan_filtering = vsc73xx_port_vlan_filtering,
···
 		dev_err(dev, "no chip found (%d)\n", ret);
 		return -ENODEV;
 	}
+
+	mutex_init(&vsc->fdb_lock);
 
 	eth_random_addr(vsc->addr);
 	dev_info(vsc->dev,

drivers/net/dsa/vitesse-vsc73xx.h

···
  * @vlans: List of configured vlans. Contains port mask and untagged status of
  *	every vlan configured in port vlan operation. It doesn't cover tag_8021q
  *	vlans.
+ * @fdb_lock: Mutex protects fdb access
  */
 struct vsc73xx {
 	struct device			*dev;
···
 	void				*priv;
 	struct vsc73xx_portinfo		portinfo[VSC73XX_MAX_NUM_PORTS];
 	struct list_head		vlans;
+	struct mutex			fdb_lock;
 };
 
 /**