net: dsa: mv88e6xxx: Add support for bridge port locked mode

Supporting bridge ports in locked mode using the drop on lock
feature in Marvell mv88e6xxx switchcores is described in the
'88E6096/88E6097/88E6097F Datasheet', sections 4.4.6, 4.4.7 and
5.1.2.1 (Drop on Lock).

This feature is implemented here facilitated by the locked port flag.
Signed-off-by: Hans Schultz <schultz.hans+netdev@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -6103,7 +6103,7 @@ static int mv88e6xxx_port_pre_bridge_flags(struct dsa_switch *ds, int port,
 	const struct mv88e6xxx_ops *ops;
 
 	if (flags.mask & ~(BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD |
-			   BR_BCAST_FLOOD))
+			   BR_BCAST_FLOOD | BR_PORT_LOCKED))
 		return -EINVAL;
 
 	ops = chip->info->ops;
@@ -6161,6 +6161,13 @@ static int mv88e6xxx_port_bridge_flags(struct dsa_switch *ds, int port,
 			goto out;
 	}
 
+	if (flags.mask & BR_PORT_LOCKED) {
+		bool locked = !!(flags.val & BR_PORT_LOCKED);
+
+		err = mv88e6xxx_port_set_lock(chip, port, locked);
+		if (err)
+			goto out;
+	}
 out:
 	mv88e6xxx_reg_unlock(chip);
 

drivers/net/dsa/mv88e6xxx/port.c

@@ -1234,6 +1234,35 @@ int mv88e6xxx_port_set_mirror(struct mv88e6xxx_chip *chip, int port,
 	return err;
 }
 
+int mv88e6xxx_port_set_lock(struct mv88e6xxx_chip *chip, int port,
+			    bool locked)
+{
+	u16 reg;
+	int err;
+
+	err = mv88e6xxx_port_read(chip, port, MV88E6XXX_PORT_CTL0, &reg);
+	if (err)
+		return err;
+
+	reg &= ~MV88E6XXX_PORT_CTL0_SA_FILT_MASK;
+	if (locked)
+		reg |= MV88E6XXX_PORT_CTL0_SA_FILT_DROP_ON_LOCK;
+
+	err = mv88e6xxx_port_write(chip, port, MV88E6XXX_PORT_CTL0, reg);
+	if (err)
+		return err;
+
+	err = mv88e6xxx_port_read(chip, port, MV88E6XXX_PORT_ASSOC_VECTOR, &reg);
+	if (err)
+		return err;
+
+	reg &= ~MV88E6XXX_PORT_ASSOC_VECTOR_LOCKED_PORT;
+	if (locked)
+		reg |= MV88E6XXX_PORT_ASSOC_VECTOR_LOCKED_PORT;
+
+	return mv88e6xxx_port_write(chip, port, MV88E6XXX_PORT_ASSOC_VECTOR, reg);
+}
+
 int mv88e6xxx_port_set_8021q_mode(struct mv88e6xxx_chip *chip, int port,
 				  u16 mode)
 {

drivers/net/dsa/mv88e6xxx/port.h

@@ -147,7 +147,11 @@
 /* Offset 0x04: Port Control Register */
 #define MV88E6XXX_PORT_CTL0					0x04
 #define MV88E6XXX_PORT_CTL0_USE_CORE_TAG			0x8000
-#define MV88E6XXX_PORT_CTL0_DROP_ON_LOCK			0x4000
+#define MV88E6XXX_PORT_CTL0_SA_FILT_MASK			0xc000
+#define MV88E6XXX_PORT_CTL0_SA_FILT_DISABLED			0x0000
+#define MV88E6XXX_PORT_CTL0_SA_FILT_DROP_ON_LOCK		0x4000
+#define MV88E6XXX_PORT_CTL0_SA_FILT_DROP_ON_UNLOCK		0x8000
+#define MV88E6XXX_PORT_CTL0_SA_FILT_DROP_ON_CPU		0xc000
 #define MV88E6XXX_PORT_CTL0_EGRESS_MODE_MASK			0x3000
 #define MV88E6XXX_PORT_CTL0_EGRESS_MODE_UNMODIFIED		0x0000
 #define MV88E6XXX_PORT_CTL0_EGRESS_MODE_UNTAGGED		0x1000
@@ -370,6 +374,9 @@ int mv88e6xxx_port_set_fid(struct mv88e6xxx_chip *chip, int port, u16 fid);
 int mv88e6xxx_port_get_pvid(struct mv88e6xxx_chip *chip, int port, u16 *pvid);
 int mv88e6xxx_port_set_pvid(struct mv88e6xxx_chip *chip, int port, u16 pvid);
 
+int mv88e6xxx_port_set_lock(struct mv88e6xxx_chip *chip, int port,
+			    bool locked);
+
 int mv88e6xxx_port_set_8021q_mode(struct mv88e6xxx_chip *chip, int port,
 				  u16 mode);
 int mv88e6095_port_tag_remap(struct mv88e6xxx_chip *chip, int port);