net: dsa: b53: Configure VLANs while not filtering

Update the B53 driver to support VLANs while not filtering. This
requires us to enable VLAN globally within the switch upon driver
initial configuration (dev->vlan_enabled).

We also need to remove the code that dealt with PVID re-configuration in
b53_vlan_filtering() since that function worked under the assumption
that it would only be called to make a bridge VLAN filtering, or not
filtering, and we would attempt to move the port's PVID accordingly.

Now that VLANs are programmed all the time, even in the case of a
non-VLAN filtering bridge, we would be programming a default_pvid for
the bridged switch ports.

We need the DSA receive path to pop the VLAN tag if it is the bridge's
default_pvid because the CPU port is always programmed tagged in the
programmed VLANs. In order to do so we utilize the
dsa_untag_bridge_pvid() helper introduced in the commit before within
net/dsa/tag_brcm.c.
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/b53/b53_common.c

@@ -1377,23 +1377,6 @@ EXPORT_SYMBOL(b53_phylink_mac_link_up);
 int b53_vlan_filtering(struct dsa_switch *ds, int port, bool vlan_filtering)
 {
 	struct b53_device *dev = ds->priv;
-	u16 pvid, new_pvid;
-
-	b53_read16(dev, B53_VLAN_PAGE, B53_VLAN_PORT_DEF_TAG(port), &pvid);
-	if (!vlan_filtering) {
-		/* Filtering is currently enabled, use the default PVID since
-		 * the bridge does not expect tagging anymore
-		 */
-		dev->ports[port].pvid = pvid;
-		new_pvid = b53_default_pvid(dev);
-	} else {
-		/* Filtering is currently disabled, restore the previous PVID */
-		new_pvid = dev->ports[port].pvid;
-	}
-
-	if (pvid != new_pvid)
-		b53_write16(dev, B53_VLAN_PAGE, B53_VLAN_PORT_DEF_TAG(port),
-			    new_pvid);
 
 	b53_enable_vlan(dev, dev->vlan_enabled, vlan_filtering);
 
@@ -2619,6 +2602,8 @@ struct b53_device *b53_switch_alloc(struct device *base,
 	dev->priv = priv;
 	dev->ops = ops;
 	ds->ops = &b53_switch_ops;
+	ds->configure_vlan_while_not_filtering = true;
+	dev->vlan_enabled = ds->configure_vlan_while_not_filtering;
 	mutex_init(&dev->reg_mutex);
 	mutex_init(&dev->stats_mutex);
 

drivers/net/dsa/b53/b53_priv.h

@@ -91,7 +91,6 @@ enum {
 struct b53_port {
 	u16		vlan_ctl_mask;
 	struct ethtool_eee eee;
-	u16		pvid;
 };
 
 struct b53_vlan {

net/dsa/tag_brcm.c

@@ -140,6 +140,11 @@ static struct sk_buff *brcm_tag_rcv_ll(struct sk_buff *skb,
 	/* Remove Broadcom tag and update checksum */
 	skb_pull_rcsum(skb, BRCM_TAG_LEN);
 
+	/* Set the MAC header to where it should point for
+	 * dsa_untag_bridge_pvid() to parse the correct VLAN header.
+	 */
+	skb_set_mac_header(skb, -ETH_HLEN);
+
 	skb->offload_fwd_mark = 1;
 
 	return skb;
@@ -191,7 +196,7 @@ static struct sk_buff *brcm_tag_rcv(struct sk_buff *skb, struct net_device *dev,
 		nskb->data - ETH_HLEN - BRCM_TAG_LEN,
 		2 * ETH_ALEN);
 
-	return nskb;
+	return dsa_untag_bridge_pvid(nskb);
 }
 
 static const struct dsa_device_ops brcm_netdev_ops = {
@@ -219,8 +224,14 @@ static struct sk_buff *brcm_tag_rcv_prepend(struct sk_buff *skb,
 					    struct net_device *dev,
 					    struct packet_type *pt)
 {
+	struct sk_buff *nskb;
+
 	/* tag is prepended to the packet */
-	return brcm_tag_rcv_ll(skb, dev, pt, ETH_HLEN);
+	nskb = brcm_tag_rcv_ll(skb, dev, pt, ETH_HLEN);
+	if (!nskb)
+		return nskb;
+
+	return dsa_untag_bridge_pvid(nskb);
 }
 
 static const struct dsa_device_ops brcm_prepend_netdev_ops = {