dsa: mv88x6xxx: Zero statistics counters

Zero the statistics counters when setting up the global
registers. Otherwise the counters will remain from the last boot if
the power has not been removed.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c
index c938d7ce5215..fd8547c2b79d 100644
--- a/drivers/net/dsa/mv88e6xxx.c
+++ b/drivers/net/dsa/mv88e6xxx.c
@@ -2005,6 +2005,12 @@ int mv88e6xxx_setup_global(struct dsa_switch *ds)
                                   0x9000 | (i << 8));
         }
 
+        /* Clear the statistics counters for all ports */
+        REG_WRITE(REG_GLOBAL, GLOBAL_STATS_OP, GLOBAL_STATS_OP_FLUSH_ALL);
+
+        /* Wait for the flush to complete. */
+        _mv88e6xxx_stats_wait(ds);
+
         return 0;
 }