net: dsa: microchip: add switch offload forwarding support

The flag offload_fwd_mark is set as the switch can forward frames by
itself.

This can be considered a fix to a problem introduced in commit
c2e866911e254067 where the port membership are not set in sync.  The flag
offload_fwd_mark just needs to be set in tag_ksz.c to prevent the software
bridge from forwarding duplicate multicast frames.

Fixes: c2e866911e254067 ("microchip: break KSZ9477 DSA driver into two files")
Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
index 89ed059..674d77e 100644 (file)
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -397,6 +397,7 @@ static void ksz9477_port_stp_state_set(struct dsa_switch *ds, int port,
        struct ksz_port *p = &dev->ports[port];
        u8 data;
        int member = -1;
+       int forward = dev->member;
 
        ksz_pread8(dev, port, P_STP_CTRL, &data);
        data &= ~(PORT_TX_ENABLE | PORT_RX_ENABLE | PORT_LEARN_DISABLE);
@@ -464,10 +465,10 @@ static void ksz9477_port_stp_state_set(struct dsa_switch *ds, int port,
        }
 
        /* When topology has changed the function ksz_update_port_member
-        * should be called to modify port forwarding behavior.  However
-        * as the offload_fwd_mark indication cannot be reported here
-        * the switch forwarding function is not enabled.
+        * should be called to modify port forwarding behavior.
         */
+       if (forward != dev->member)
+               ksz_update_port_member(dev, port);
 }
 
 static void ksz9477_flush_dyn_mac_table(struct ksz_device *dev, int port)

diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
index da71b9e..927e9c8 100644 (file)
--- a/net/dsa/tag_ksz.c
+++ b/net/dsa/tag_ksz.c
@@ -67,6 +67,8 @@ static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
 
        pskb_trim_rcsum(skb, skb->len - len);
 
+       skb->offload_fwd_mark = true;
+
        return skb;
 }