[RFC PATCH net-next 11/16] net: mscc: ocelot: set up logical port IDs centrally

[Vladimir Oltean]

The setup of logical port IDs is done in two places: from the inconclusively
named ocelot_setup_lag and from ocelot_port_lag_leave, a function that
also calls ocelot_setup_lag (which apparently does an incomplete setup
of the LAG).

To improve this situation, we can rename ocelot_setup_lag into
ocelot_setup_logical_port_ids, and drop the "lag" argument. It will now
set up the logical port IDs of all switch ports, which may be just
slightly more inefficient but more maintainable.

Signed-off-by: Vladimir Oltean <vladimir.olt...@nxp.com>
---
 drivers/net/ethernet/mscc/ocelot.c | 47 ++++++++++++++++++------------
 1 file changed, 28 insertions(+), 19 deletions(-)

diff --git a/drivers/net/ethernet/mscc/ocelot.c 
b/drivers/net/ethernet/mscc/ocelot.c
index ee0fcee8e09a..1a98c24af056 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -1279,20 +1279,36 @@ static void ocelot_set_aggr_pgids(struct ocelot *ocelot)
        }
 }
 
-static void ocelot_setup_lag(struct ocelot *ocelot, int lag)
+/* When offloading a bonding interface, the switch ports configured under the
+ * same bond must have the same logical port ID, equal to the physical port ID
+ * of the lowest numbered physical port in that bond. Otherwise, in standalone/
+ * bridged mode, each port has a logical port ID equal to its physical port ID.
+ */
+static void ocelot_setup_logical_port_ids(struct ocelot *ocelot)
 {
-       unsigned long bond_mask = ocelot->lags[lag];
-       unsigned int p;
+       int port;
 
-       for_each_set_bit(p, &bond_mask, ocelot->num_phys_ports) {
-               u32 port_cfg = ocelot_read_gix(ocelot, ANA_PORT_PORT_CFG, p);
+       for (port = 0; port < ocelot->num_phys_ports; port++) {
+               struct ocelot_port *ocelot_port = ocelot->ports[port];
+               struct net_device *bond;
+
+               if (!ocelot_port)
+                       continue;
 
-               port_cfg &= ~ANA_PORT_PORT_CFG_PORTID_VAL_M;
+               bond = ocelot_port->bond;
+               if (bond) {
+                       int lag = __ffs(ocelot_get_bond_mask(ocelot, bond));
 
-               /* Use lag port as logical port for port i */
-               ocelot_write_gix(ocelot, port_cfg |
-                                ANA_PORT_PORT_CFG_PORTID_VAL(lag),
-                                ANA_PORT_PORT_CFG, p);
+                       ocelot_rmw_gix(ocelot,
+                                      ANA_PORT_PORT_CFG_PORTID_VAL(lag),
+                                      ANA_PORT_PORT_CFG_PORTID_VAL_M,
+                                      ANA_PORT_PORT_CFG, port);
+               } else {
+                       ocelot_rmw_gix(ocelot,
+                                      ANA_PORT_PORT_CFG_PORTID_VAL(port),
+                                      ANA_PORT_PORT_CFG_PORTID_VAL_M,
+                                      ANA_PORT_PORT_CFG, port);
+               }
        }
 }
 
@@ -1320,7 +1336,7 @@ int ocelot_port_lag_join(struct ocelot *ocelot, int port,
                ocelot->lags[lag] |= BIT(port);
        }
 
-       ocelot_setup_lag(ocelot, lag);
+       ocelot_setup_logical_port_ids(ocelot);
        ocelot_apply_bridge_fwd_mask(ocelot);
        ocelot_set_aggr_pgids(ocelot);
 
@@ -1331,7 +1347,6 @@ EXPORT_SYMBOL(ocelot_port_lag_join);
 void ocelot_port_lag_leave(struct ocelot *ocelot, int port,
                           struct net_device *bond)
 {
-       u32 port_cfg;
        int i;
 
        ocelot->ports[port]->bond = NULL;
@@ -1348,15 +1363,9 @@ void ocelot_port_lag_leave(struct ocelot *ocelot, int 
port,
 
                ocelot->lags[n] = ocelot->lags[port];
                ocelot->lags[port] = 0;
-
-               ocelot_setup_lag(ocelot, n);
        }
 
-       port_cfg = ocelot_read_gix(ocelot, ANA_PORT_PORT_CFG, port);
-       port_cfg &= ~ANA_PORT_PORT_CFG_PORTID_VAL_M;
-       ocelot_write_gix(ocelot, port_cfg | ANA_PORT_PORT_CFG_PORTID_VAL(port),
-                        ANA_PORT_PORT_CFG, port);
-
+       ocelot_setup_logical_port_ids(ocelot);
        ocelot_apply_bridge_fwd_mask(ocelot);
        ocelot_set_aggr_pgids(ocelot);
 }
-- 
2.25.1