Subject: [PATCH v6 net-next 8/9] net: dsa: mv88e6xxx: add blackhole ATU entries

From: Hans Schultz <[email-masked]>
Date: Wed, 28 Sep 2022 17:02:55 +0200

From: "Hans J. Schultz" <[email-masked]>

Blackhole FDB entries can now be added, deleted or replaced in the
driver ATU.

Signed-off-by: Hans J. Schultz <[email-masked]>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 78 ++++++++++++++++++++++++++++++--
 1 file changed, 74 insertions(+), 4 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 71843fe87f77..a17f30e5d4a6 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -2735,6 +2735,72 @@ static int mv88e6xxx_vlan_msti_set(struct dsa_switch *ds,
 	return err;
 }
 
+struct mv88e6xxx_vid_search_ctx {
+	u16 vid_search;
+	u16 fid_found;
+};
+
+static int mv88e6xxx_find_fid_on_matching_vid(struct mv88e6xxx_chip *chip,
+					      const struct mv88e6xxx_vtu_entry *entry,
+					      void *priv)
+{
+	struct mv88e6xxx_vid_search_ctx *ctx = priv;
+
+	if (ctx->vid_search == entry->vid) {
+		ctx->fid_found = entry->fid;
+		return 1;
+	}
+
+	return 0;
+}
+
+static int mv88e6xxx_blackhole_fdb_loadpurge(struct dsa_switch *ds,
+					     const unsigned char *addr, u16 vid, u8 state)
+{
+	struct mv88e6xxx_chip *chip = ds->priv;
+	struct mv88e6xxx_vid_search_ctx ctx;
+	struct mv88e6xxx_atu_entry entry;
+	u16 fid = 0;
+	int err;
+
+	ether_addr_copy(entry.mac, addr);
+	entry.portvec = MV88E6XXX_G1_ATU_DATA_PORT_VECTOR_NO_EGRESS;
+	entry.state = state;
+	entry.trunk = false;
+
+	ctx.vid_search = vid;
+	mv88e6xxx_reg_lock(chip);
+	err = mv88e6xxx_vtu_walk(chip, mv88e6xxx_find_fid_on_matching_vid, &ctx);
+	mv88e6xxx_reg_unlock(chip);
+	if (err < 0)
+		return err;
+	if (err == 1)
+		fid = ctx.fid_found;
+	else
+		return -ENODATA;
+
+	if (!fid)
+		return -ENODATA;
+
+	mv88e6xxx_reg_lock(chip);
+	err = mv88e6xxx_g1_atu_loadpurge(chip, fid, &entry);
+	mv88e6xxx_reg_unlock(chip);
+
+	return err;
+}
+
+int mv88e6xxx_blackhole_fdb_add(struct dsa_switch *ds, const unsigned char *addr, u16 vid)
+{
+	return mv88e6xxx_blackhole_fdb_loadpurge(ds, addr, vid,
+						 MV88E6XXX_G1_ATU_DATA_STATE_UC_STATIC);
+}
+
+int mv88e6xxx_blackhole_fdb_del(struct dsa_switch *ds, const unsigned char *addr, u16 vid)
+{
+	return mv88e6xxx_blackhole_fdb_loadpurge(ds, addr, vid,
+						 MV88E6XXX_G1_ATU_DATA_STATE_UC_UNUSED);
+}
+
 static int mv88e6xxx_port_fdb_add(struct dsa_switch *ds, int port,
 				  const unsigned char *addr, u16 vid,
 				  u16 fdb_flags, struct dsa_db db)
@@ -2742,9 +2808,12 @@ static int mv88e6xxx_port_fdb_add(struct dsa_switch *ds, int port,
 	struct mv88e6xxx_chip *chip = ds->priv;
 	int err;
 
-	/* Ignore entries with flags set */
-	if (fdb_flags)
+	if (fdb_flags & DSA_FDB_FLAG_LOCKED)
 		return 0;
+	if (fdb_flags & DSA_FDB_FLAG_BLACKHOLE) {
+		mv88e6xxx_blackhole_fdb_del(ds, addr, vid);
+		return mv88e6xxx_blackhole_fdb_add(ds, addr, vid);
+	}
 
 	if (mv88e6xxx_port_is_locked(chip, port))
 		mv88e6xxx_atu_locked_entry_find_purge(ds, port, addr, vid);
@@ -2765,9 +2834,10 @@ static int mv88e6xxx_port_fdb_del(struct dsa_switch *ds, int port,
 	bool locked_found = false;
 	int err = 0;
 
-	/* Ignore entries with flags set */
-	if (fdb_flags)
+	if (fdb_flags & DSA_FDB_FLAG_LOCKED)
 		return 0;
+	if (fdb_flags & DSA_FDB_FLAG_BLACKHOLE)
+		return mv88e6xxx_blackhole_fdb_del(ds, addr, vid);
 
 	if (mv88e6xxx_port_is_locked(chip, port))
 		locked_found = mv88e6xxx_atu_locked_entry_find_purge(ds, port, addr, vid);
-- 
2.34.1