diff mbox series

[net,1/2] mlxsw: core: Add validation of transceiver temperature thresholds

Message ID 20210108145210.1229820-2-idosch@idosch.org (mailing list archive)
State Accepted
Commit 57726ebe2733891c9f59105eff028735f73d05fb
Delegated to: Netdev Maintainers
Headers show
Series mlxsw: core: Thermal control fixes | expand

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netdev/cc_maintainers warning 1 maintainers not CCed: vadimp@mellanox.com
netdev/source_inline success Was 0 now: 0
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netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 43 this patch: 43
netdev/kdoc success Errors and warnings before: 0 this patch: 0
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netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 24 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 35 this patch: 35
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netdev/stable success Stable not CCed

Commit Message

Ido Schimmel Jan. 8, 2021, 2:52 p.m. UTC 
From: Vadim Pasternak <vadimp@nvidia.com>

Validate thresholds to avoid a single failure due to some transceiver
unreliability. Ignore the last readouts in case warning temperature is
above alarm temperature, since it can cause unexpected thermal
shutdown. Stay with the previous values and refresh threshold within
the next iteration.

This is a rare scenario, but it was observed at a customer site.

Fixes: 6a79507cfe94 ("mlxsw: core: Extend thermal module with per QSFP module thermal zones")
Signed-off-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlxsw/core_thermal.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c b/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c
index 8fa286ccdd6b..250a85049697 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_thermal.c
@@ -176,6 +176,12 @@  mlxsw_thermal_module_trips_update(struct device *dev, struct mlxsw_core *core,
 	if (err)
 		return err;
 
+	if (crit_temp > emerg_temp) {
+		dev_warn(dev, "%s : Critical threshold %d is above emergency threshold %d\n",
+			 tz->tzdev->type, crit_temp, emerg_temp);
+		return 0;
+	}
+
 	/* According to the system thermal requirements, the thermal zones are
 	 * defined with four trip points. The critical and emergency
 	 * temperature thresholds, provided by QSFP module are set as "active"
@@ -190,11 +196,8 @@  mlxsw_thermal_module_trips_update(struct device *dev, struct mlxsw_core *core,
 		tz->trips[MLXSW_THERMAL_TEMP_TRIP_NORM].temp = crit_temp;
 	tz->trips[MLXSW_THERMAL_TEMP_TRIP_HIGH].temp = crit_temp;
 	tz->trips[MLXSW_THERMAL_TEMP_TRIP_HOT].temp = emerg_temp;
-	if (emerg_temp > crit_temp)
-		tz->trips[MLXSW_THERMAL_TEMP_TRIP_CRIT].temp = emerg_temp +
+	tz->trips[MLXSW_THERMAL_TEMP_TRIP_CRIT].temp = emerg_temp +
 					MLXSW_THERMAL_MODULE_TEMP_SHIFT;
-	else
-		tz->trips[MLXSW_THERMAL_TEMP_TRIP_CRIT].temp = emerg_temp;
 
 	return 0;
 }