From: Russell King rmk+kernel@armlinux.org.uk
[ Upstream commit fad58190c0ffd72c394722928cd3e919b6e18357 ]
If in-band negotiation or fixed-link modes are specified for a DSA port, the DSA code will force the link down during initialisation. For fixed-link mode, this is fine, as phylink will manage the link state. However, for in-band mode, phylink expects the PCS to detect link, which will not happen if the link is forced down.
There is a related issue that in in-band mode, the link could come up while we are making configuration changes, so we should force the link down prior to reconfiguring the interface mode.
This patch addresses both issues.
Fixes: 3be98b2d5fbc ("net: dsa: Down cpu/dsa ports phylink will control") Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Reviewed-by: Andrew Lunn andrew@lunn.ch Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/dsa/mv88e6xxx/chip.c | 22 +++++++++++++++++++--- drivers/net/dsa/mv88e6xxx/chip.h | 1 + 2 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c index 2b4a723c83065..e065be419a03d 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.c +++ b/drivers/net/dsa/mv88e6xxx/chip.c @@ -664,8 +664,11 @@ static void mv88e6xxx_mac_config(struct dsa_switch *ds, int port, const struct phylink_link_state *state) { struct mv88e6xxx_chip *chip = ds->priv; + struct mv88e6xxx_port *p; int err;
+ p = &chip->ports[port]; + /* FIXME: is this the correct test? If we're in fixed mode on an * internal port, why should we process this any different from * PHY mode? On the other hand, the port may be automedia between @@ -675,10 +678,14 @@ static void mv88e6xxx_mac_config(struct dsa_switch *ds, int port, return;
mv88e6xxx_reg_lock(chip); - /* FIXME: should we force the link down here - but if we do, how - * do we restore the link force/unforce state? The driver layering - * gets in the way. + /* In inband mode, the link may come up at any time while the link + * is not forced down. Force the link down while we reconfigure the + * interface mode. */ + if (mode == MLO_AN_INBAND && p->interface != state->interface && + chip->info->ops->port_set_link) + chip->info->ops->port_set_link(chip, port, LINK_FORCED_DOWN); + err = mv88e6xxx_port_config_interface(chip, port, state->interface); if (err && err != -EOPNOTSUPP) goto err_unlock; @@ -691,6 +698,15 @@ static void mv88e6xxx_mac_config(struct dsa_switch *ds, int port, if (err > 0) err = 0;
+ /* Undo the forced down state above after completing configuration + * irrespective of its state on entry, which allows the link to come up. + */ + if (mode == MLO_AN_INBAND && p->interface != state->interface && + chip->info->ops->port_set_link) + chip->info->ops->port_set_link(chip, port, LINK_UNFORCED); + + p->interface = state->interface; + err_unlock: mv88e6xxx_reg_unlock(chip);
diff --git a/drivers/net/dsa/mv88e6xxx/chip.h b/drivers/net/dsa/mv88e6xxx/chip.h index e5430cf2ad711..6476524e8239d 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.h +++ b/drivers/net/dsa/mv88e6xxx/chip.h @@ -232,6 +232,7 @@ struct mv88e6xxx_port { u64 atu_full_violation; u64 vtu_member_violation; u64 vtu_miss_violation; + phy_interface_t interface; u8 cmode; bool mirror_ingress; bool mirror_egress;