[PATCH net-next v2] net: dsa: mt7530: support MDB operations

[DENG Qingfang]

Support port MDB add to/delete from MT7530 ARL.

As the hardware can manage multicast forwarding itself, trapping
multicast traffic to the CPU is no longer required.

Signed-off-by: DENG Qingfang <dqfext at gmail.com>
---
v1 -> v2: fix commit message

 drivers/net/dsa/mt7530.c | 58 +++++++++++++++++++++++++++++++++++++---
 net/dsa/tag_mtk.c        | 14 +---------
 2 files changed, 56 insertions(+), 16 deletions(-)

diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c
index 28aab0ff6e7d..20e66cf13485 100644
--- a/drivers/net/dsa/mt7530.c
+++ b/drivers/net/dsa/mt7530.c
@@ -1000,9 +1000,6 @@ mt753x_cpu_port_enable(struct dsa_switch *ds, int port)
 	mt7530_write(priv, MT7530_PVC_P(port),
 		     PORT_SPEC_TAG);
 
-	/* Unknown multicast frame forwarding to the cpu port */
-	mt7530_rmw(priv, MT7530_MFC, UNM_FFP_MASK, UNM_FFP(BIT(port)));
-
 	/* Set CPU port number */
 	if (priv->id == ID_MT7621)
 		mt7530_rmw(priv, MT7530_MFC, CPU_MASK, CPU_EN | CPU_PORT(port));
@@ -1365,6 +1362,59 @@ mt7530_port_fdb_dump(struct dsa_switch *ds, int port,
 	return 0;
 }
 
+static int
+mt7530_port_mdb_add(struct dsa_switch *ds, int port,
+		    const struct switchdev_obj_port_mdb *mdb)
+{
+	struct mt7530_priv *priv = ds->priv;
+	const u8 *addr = mdb->addr;
+	u16 vid = mdb->vid;
+	u8 port_mask = 0;
+	int ret;
+
+	mutex_lock(&priv->reg_mutex);
+
+	mt7530_fdb_write(priv, vid, 0, addr, 0, STATIC_EMP);
+	if (!mt7530_fdb_cmd(priv, MT7530_FDB_READ, NULL))
+		port_mask = (mt7530_read(priv, MT7530_ATRD) >> PORT_MAP)
+			    & PORT_MAP_MASK;
+
+	port_mask |= BIT(port);
+	mt7530_fdb_write(priv, vid, port_mask, addr, -1, STATIC_ENT);
+	ret = mt7530_fdb_cmd(priv, MT7530_FDB_WRITE, NULL);
+
+	mutex_unlock(&priv->reg_mutex);
+
+	return ret;
+}
+
+static int
+mt7530_port_mdb_del(struct dsa_switch *ds, int port,
+		    const struct switchdev_obj_port_mdb *mdb)
+{
+	struct mt7530_priv *priv = ds->priv;
+	const u8 *addr = mdb->addr;
+	u16 vid = mdb->vid;
+	u8 port_mask = 0;
+	int ret;
+
+	mutex_lock(&priv->reg_mutex);
+
+	mt7530_fdb_write(priv, vid, 0, addr, 0, STATIC_EMP);
+	if (!mt7530_fdb_cmd(priv, MT7530_FDB_READ, NULL))
+		port_mask = (mt7530_read(priv, MT7530_ATRD) >> PORT_MAP)
+			    & PORT_MAP_MASK;
+
+	port_mask &= ~BIT(port);
+	mt7530_fdb_write(priv, vid, port_mask, addr, -1,
+			 port_mask ? STATIC_ENT : STATIC_EMP);
+	ret = mt7530_fdb_cmd(priv, MT7530_FDB_WRITE, NULL);
+
+	mutex_unlock(&priv->reg_mutex);
+
+	return ret;
+}
+
 static int
 mt7530_vlan_cmd(struct mt7530_priv *priv, enum mt7530_vlan_cmd cmd, u16 vid)
 {
@@ -3403,6 +3453,8 @@ static const struct dsa_switch_ops mt7530_switch_ops = {
 	.port_fdb_add		= mt7530_port_fdb_add,
 	.port_fdb_del		= mt7530_port_fdb_del,
 	.port_fdb_dump		= mt7530_port_fdb_dump,
+	.port_mdb_add		= mt7530_port_mdb_add,
+	.port_mdb_del		= mt7530_port_mdb_del,
 	.port_vlan_filtering	= mt7530_port_vlan_filtering,
 	.port_vlan_add		= mt7530_port_vlan_add,
 	.port_vlan_del		= mt7530_port_vlan_del,
diff --git a/net/dsa/tag_mtk.c b/net/dsa/tag_mtk.c
index 38dcdded74c0..53b620e177ad 100644
--- a/net/dsa/tag_mtk.c
+++ b/net/dsa/tag_mtk.c
@@ -23,9 +23,6 @@ static struct sk_buff *mtk_tag_xmit(struct sk_buff *skb,
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	u8 *mtk_tag;
 	bool is_vlan_skb = true;
-	unsigned char *dest = eth_hdr(skb)->h_dest;
-	bool is_multicast_skb = is_multicast_ether_addr(dest) &&
-				!is_broadcast_ether_addr(dest);
 
 	/* Build the special tag after the MAC Source Address. If VLAN header
 	 * is present, it's required that VLAN header and special tag is
@@ -48,10 +45,6 @@ static struct sk_buff *mtk_tag_xmit(struct sk_buff *skb,
 		     MTK_HDR_XMIT_UNTAGGED;
 	mtk_tag[1] = (1 << dp->index) & MTK_HDR_XMIT_DP_BIT_MASK;
 
-	/* Disable SA learning for multicast frames */
-	if (unlikely(is_multicast_skb))
-		mtk_tag[1] |= MTK_HDR_XMIT_SA_DIS;
-
 	/* Tag control information is kept for 802.1Q */
 	if (!is_vlan_skb) {
 		mtk_tag[2] = 0;
@@ -67,9 +60,6 @@ static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 	u16 hdr;
 	int port;
 	__be16 *phdr;
-	unsigned char *dest = eth_hdr(skb)->h_dest;
-	bool is_multicast_skb = is_multicast_ether_addr(dest) &&
-				!is_broadcast_ether_addr(dest);
 
 	if (unlikely(!pskb_may_pull(skb, MTK_HDR_LEN)))
 		return NULL;
@@ -95,9 +85,7 @@ static struct sk_buff *mtk_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 	if (!skb->dev)
 		return NULL;
 
-	/* Only unicast or broadcast frames are offloaded */
-	if (likely(!is_multicast_skb))
-		skb->offload_fwd_mark = 1;
+	skb->offload_fwd_mark = 1;
 
 	return skb;
 }
-- 
2.25.1