Merge branch 'mv88e6xxx-mtu-fixes'

Andrew Lunn says:

====================
mv88e6xxx: MTU fixes

These three patches fix MTU issues reported by 曹煜.

There are two different ways of configuring the MTU in the hardware.
The 6161 family is using the wrong method. Some of the marvell switch
enforce the MTU when the port is used for CPU/DSA, some don't.
Because of the extra header, the MTU needs increasing with this
overhead.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/mv88e6xxx/chip.c

@@ -2834,8 +2834,8 @@ static int mv88e6xxx_setup_port(struct mv88e6xxx_chip *chip, int port)
 	if (err)
 		return err;
 
-	/* Port Control 2: don't force a good FCS, set the maximum frame size to
-	 * 10240 bytes, disable 802.1q tags checking, don't discard tagged or
+	/* Port Control 2: don't force a good FCS, set the MTU size to
+	 * 10222 bytes, disable 802.1q tags checking, don't discard tagged or
 	 * untagged frames on this port, do a destination address lookup on all
 	 * received packets as usual, disable ARP mirroring and don't send a
 	 * copy of all transmitted/received frames on this port to the CPU.
@@ -2854,7 +2854,7 @@ static int mv88e6xxx_setup_port(struct mv88e6xxx_chip *chip, int port)
 		return err;
 
 	if (chip->info->ops->port_set_jumbo_size) {
-		err = chip->info->ops->port_set_jumbo_size(chip, port, 10240);
+		err = chip->info->ops->port_set_jumbo_size(chip, port, 10218);
 		if (err)
 			return err;
 	}
@@ -2944,10 +2944,10 @@ static int mv88e6xxx_get_max_mtu(struct dsa_switch *ds, int port)
 	struct mv88e6xxx_chip *chip = ds->priv;
 
 	if (chip->info->ops->port_set_jumbo_size)
-		return 10240;
+		return 10240 - VLAN_ETH_HLEN - EDSA_HLEN - ETH_FCS_LEN;
 	else if (chip->info->ops->set_max_frame_size)
-		return 1632;
-	return 1522;
+		return 1632 - VLAN_ETH_HLEN - EDSA_HLEN - ETH_FCS_LEN;
+	return 1522 - VLAN_ETH_HLEN - EDSA_HLEN - ETH_FCS_LEN;
 }
 
 static int mv88e6xxx_change_mtu(struct dsa_switch *ds, int port, int new_mtu)
@@ -2955,6 +2955,9 @@ static int mv88e6xxx_change_mtu(struct dsa_switch *ds, int port, int new_mtu)
 	struct mv88e6xxx_chip *chip = ds->priv;
 	int ret = 0;
 
+	if (dsa_is_dsa_port(ds, port) || dsa_is_cpu_port(ds, port))
+		new_mtu += EDSA_HLEN;
+
 	mv88e6xxx_reg_lock(chip);
 	if (chip->info->ops->port_set_jumbo_size)
 		ret = chip->info->ops->port_set_jumbo_size(chip, port, new_mtu);
@@ -3725,7 +3728,6 @@ static const struct mv88e6xxx_ops mv88e6161_ops = {
 	.port_set_ucast_flood = mv88e6352_port_set_ucast_flood,
 	.port_set_mcast_flood = mv88e6352_port_set_mcast_flood,
 	.port_set_ether_type = mv88e6351_port_set_ether_type,
-	.port_set_jumbo_size = mv88e6165_port_set_jumbo_size,
 	.port_egress_rate_limiting = mv88e6097_port_egress_rate_limiting,
 	.port_pause_limit = mv88e6097_port_pause_limit,
 	.port_disable_learn_limit = mv88e6xxx_port_disable_learn_limit,
@@ -3750,6 +3752,7 @@ static const struct mv88e6xxx_ops mv88e6161_ops = {
 	.avb_ops = &mv88e6165_avb_ops,
 	.ptp_ops = &mv88e6165_ptp_ops,
 	.phylink_validate = mv88e6185_phylink_validate,
+	.set_max_frame_size = mv88e6185_g1_set_max_frame_size,
 };
 
 static const struct mv88e6xxx_ops mv88e6165_ops = {

drivers/net/dsa/mv88e6xxx/chip.h

@@ -18,6 +18,7 @@
 #include <linux/timecounter.h>
 #include <net/dsa.h>
 
+#define EDSA_HLEN		8
 #define MV88E6XXX_N_FID		4096
 
 /* PVT limits for 4-bit port and 5-bit switch */

drivers/net/dsa/mv88e6xxx/global1.c

@@ -232,6 +232,8 @@ int mv88e6185_g1_set_max_frame_size(struct mv88e6xxx_chip *chip, int mtu)
 	u16 val;
 	int err;
 
+	mtu += ETH_HLEN + ETH_FCS_LEN;
+
 	err = mv88e6xxx_g1_read(chip, MV88E6XXX_G1_CTL1, &val);
 	if (err)
 		return err;

drivers/net/dsa/mv88e6xxx/port.c

@@ -1277,6 +1277,8 @@ int mv88e6165_port_set_jumbo_size(struct mv88e6xxx_chip *chip, int port,
 	u16 reg;
 	int err;
 
+	size += VLAN_ETH_HLEN + ETH_FCS_LEN;
+
 	err = mv88e6xxx_port_read(chip, port, MV88E6XXX_PORT_CTL2, &reg);
 	if (err)
 		return err;