net: dsa: microchip: ksz8795: Fix VLAN filtering

[ Upstream commit 164844135a3f215d3018ee9d6875336beb942413 ]

Currently ksz8_port_vlan_filtering() sets or clears the VLAN Enable
hardware flag.  That controls discarding of packets with a VID that
has not been enabled for any port on the switch.

Since it is a global flag, set the dsa_switch::vlan_filtering_is_global
flag so that the DSA core understands this can't be controlled per
port.

When VLAN filtering is enabled, the switch should also discard packets
with a VID that's not enabled on the ingress port.  Set or clear each
external port's VLAN Ingress Filter flag in ksz8_port_vlan_filtering()
to make that happen.

Fixes: e66f840c08a2 ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/dsa/microchip/ksz8795.c b/drivers/net/dsa/microchip/ksz8795.c
index 1e101ab56cea113a637a2d6294ef3068b3638eef..108a14db1f1a84a99c50d7fb91ccb15ef4477cdd 100644 (file)
--- a/drivers/net/dsa/microchip/ksz8795.c
+++ b/drivers/net/dsa/microchip/ksz8795.c
@@ -790,8 +790,14 @@ static int ksz8795_port_vlan_filtering(struct dsa_switch *ds, int port,
        if (switchdev_trans_ph_prepare(trans))
                return 0;
 
+       /* Discard packets with VID not enabled on the switch */
        ksz_cfg(dev, S_MIRROR_CTRL, SW_VLAN_ENABLE, flag);
 
+       /* Discard packets with VID not enabled on the ingress port */
+       for (port = 0; port < dev->phy_port_cnt; ++port)
+               ksz_port_cfg(dev, port, REG_PORT_CTRL_2, PORT_INGRESS_FILTER,
+                            flag);
+
        return 0;
 }
 
@@ -1266,6 +1272,11 @@ static int ksz8795_switch_init(struct ksz_device *dev)
        /* set the real number of ports */
        dev->ds->num_ports = dev->port_cnt + 1;
 
+       /* VLAN filtering is partly controlled by the global VLAN
+        * Enable flag
+        */
+       dev->ds->vlan_filtering_is_global = true;
+
        return 0;
 }