iwlwifi: mvm: add thermal throttling debugging

Add prints visible to the user when entering and exiting
thrermal throttling, because so users can tell that the
NIC is getting too hot (and throughput will decrease.)

Signed-off-by: eytan lifshitz <eytan.lifshitz@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

drivers/net/wireless/iwlwifi/mvm/mvm.h

@@ -352,12 +352,14 @@ struct iwl_tt_params {
  * @dynamic_smps: Is thermal throttling enabled dynamic_smps?
  * @tx_backoff: The current thremal throttling tx backoff in uSec.
  * @params: Parameters to configure the thermal throttling algorithm.
+ * @throttle: Is thermal throttling is active?
  */
 struct iwl_mvm_tt_mgmt {
 	struct delayed_work ct_kill_exit;
 	bool dynamic_smps;
 	u32 tx_backoff;
 	const struct iwl_tt_params *params;
+	bool throttle;
 };
 
 struct iwl_mvm {

drivers/net/wireless/iwlwifi/mvm/tt.c

@@ -427,6 +427,7 @@ void iwl_mvm_tt_handler(struct iwl_mvm *mvm)
 	const struct iwl_tt_params *params = mvm->thermal_throttle.params;
 	struct iwl_mvm_tt_mgmt *tt = &mvm->thermal_throttle;
 	s32 temperature = mvm->temperature;
+	bool throttle_enable = false;
 	int i;
 	u32 tx_backoff;
 
@@ -445,6 +446,7 @@ void iwl_mvm_tt_handler(struct iwl_mvm *mvm)
 			ieee80211_iterate_active_interfaces_atomic(
 					mvm->hw, IEEE80211_IFACE_ITER_NORMAL,
 					iwl_mvm_tt_smps_iterator, mvm);
+			throttle_enable = true;
 		} else if (tt->dynamic_smps &&
 			   temperature <= params->dynamic_smps_exit) {
 			IWL_DEBUG_TEMP(mvm, "Disable dynamic SMPS\n");
@@ -456,10 +458,12 @@ void iwl_mvm_tt_handler(struct iwl_mvm *mvm)
 	}
 
 	if (params->support_tx_protection) {
-		if (temperature >= params->tx_protection_entry)
+		if (temperature >= params->tx_protection_entry) {
 			iwl_mvm_tt_tx_protection(mvm, true);
-		else if (temperature <= params->tx_protection_exit)
+			throttle_enable = true;
+		} else if (temperature <= params->tx_protection_exit) {
 			iwl_mvm_tt_tx_protection(mvm, false);
+		}
 	}
 
 	if (params->support_tx_backoff) {
@@ -469,9 +473,22 @@ void iwl_mvm_tt_handler(struct iwl_mvm *mvm)
 				break;
 			tx_backoff = params->tx_backoff[i].backoff;
 		}
+		if (tx_backoff != 0)
+			throttle_enable = true;
 		if (tt->tx_backoff != tx_backoff)
 			iwl_mvm_tt_tx_backoff(mvm, tx_backoff);
 	}
+
+	if (!tt->throttle && throttle_enable) {
+		IWL_WARN(mvm,
+			 "Due to high temperature thermal throttling initiated\n");
+		tt->throttle = true;
+	} else if (tt->throttle && !tt->dynamic_smps && tt->tx_backoff == 0 &&
+		   temperature <= params->tx_protection_exit) {
+		IWL_WARN(mvm,
+			 "Temperature is back to normal thermal throttling stopped\n");
+		tt->throttle = false;
+	}
 }
 
 static const struct iwl_tt_params iwl7000_tt_params = {
@@ -502,6 +519,7 @@ void iwl_mvm_tt_initialize(struct iwl_mvm *mvm)
 
 	IWL_DEBUG_TEMP(mvm, "Initialize Thermal Throttling\n");
 	tt->params = &iwl7000_tt_params;
+	tt->throttle = false;
 	INIT_DELAYED_WORK(&tt->ct_kill_exit, check_exit_ctkill);
 }