[PATCH net 0/2] net: dsa: mv88e6xxx: 88E6171 stats fixes

[PATCH net 0/2] net: dsa: mv88e6xxx: 88E6171 stats fixes

[Florian Fainelli]

These two patches fixes statistics on the 88E6171 present on the Linksys
EA4500 router. These changes were found during testing using a
resurrected version of Andrew's dsa-tests:

https://github.com/lunn/dsa-tests

Florian Fainelli (2):
  net: dsa: mv88e6xxx: fix 88E6171 statistics snapshot
  net: dsa: mv88e6xxx: fix 88E6171 statistics type

 drivers/net/dsa/mv88e6xxx/chip.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.53.0

[PATCH net 1/2] net: dsa: mv88e6xxx: fix 88E6171 statistics snapshot

[Florian Fainelli]

The 88E6171 belongs to the 6351 family and takes the port number in the
low bits of the statistics operation register. The 6320 snapshot helper
instead encodes the port as (port + 1) << 5. On an EA4500, this causes
ethtool -S to return physical port 0's MIB counters for every user port.
Traffic on other ports does not update their reported hardware counters.

Before the snapshot operation was moved into the chip operations, only
the 6320 and 6352 families used the shifted encoding. The refactoring
incorrectly assigned that encoding to the 88E6171 as well.

Use the unshifted snapshot helper for the 88E6171. Tested on an EA4500:
pings through different switch ports now update only the corresponding
port's hardware counters.

Fixes: a605a0fe7115 ("net: dsa: mv88e6xxx: Abstract stats_snapshot into ops structure")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 7f68a0c55802..67daf3b9cb48 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -4610,7 +4610,7 @@ static const struct mv88e6xxx_ops mv88e6171_ops = {
 	.port_disable_pri_override = mv88e6xxx_port_disable_pri_override,
 	.port_get_cmode = mv88e6352_port_get_cmode,
 	.port_setup_message_port = mv88e6xxx_setup_message_port,
-	.stats_snapshot = mv88e6320_g1_stats_snapshot,
+	.stats_snapshot = mv88e6xxx_g1_stats_snapshot,
 	.stats_set_histogram = mv88e6095_g1_stats_set_histogram,
 	.stats_get_sset_count = mv88e6095_stats_get_sset_count,
 	.stats_get_strings = mv88e6095_stats_get_strings,
-- 
2.53.0

[PATCH net 2/2] net: dsa: mv88e6xxx: fix 88E6171 statistics type

[Florian Fainelli]

The 88E6171 uses the 6095 statistics operations, which advertise and name
BANK0 and PORT counters. Its stats_type bitmap instead selects BANK0 and
BANK1. Since statistics collection started using that bitmap, it has
written a different set of counters from the one advertised to ethtool.

For this chip, get_sset_count() accounts for 30 BANK0 counters, three
PORT counters and five ATU/VTU counters. Collection instead writes 30
BANK0 counters, 26 BANK1 counters and five ATU/VTU counters: 61 entries
rather than the advertised 38. This mislabels the tail of the returned
statistics and writes past the advertised statistics buffer.

Select BANK0 and PORT counters to match the chip's statistics operations
and restore the filter used before the bitmap was introduced. Tested on
an EA4500, where the two-bridge forwarding and multicast snooping tests
now pass their hardware counter checks.

Fixes: 5595e3613ea7 ("dsa: mv88e6xxx: Move available stats into info structure")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 67daf3b9cb48..ebd9f69a7ed7 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -5960,7 +5960,7 @@ static const struct mv88e6xxx_info mv88e6xxx_table[] = {
 		.age_time_coeff = 15000,
 		.g1_irqs = 9,
 		.g2_irqs = 10,
-		.stats_type = STATS_TYPE_BANK0 | STATS_TYPE_BANK1,
+		.stats_type = STATS_TYPE_BANK0 | STATS_TYPE_PORT,
 		.atu_move_port_mask = 0xf,
 		.pvt = true,
 		.multi_chip = true,
-- 
2.53.0