[RFC PATCH 2/2] ath10k: regularly fetch survey counters

[Sven Eckelmann <sven@narfation.org>]

From: Sven Eckelmann <seckelmann@datto.com>

The survey counters from firmwares like 10.2.4 are not actually using the
full 64 bit. Instead, they only use the lower 31 bit and overflow ever
14-30s. The driver must frequently fetch the survey data and add it to the
survey data storage to avoid this problem and to present meaningful values
to the caller of .get_survey.

It is assumed for now that only the current rx_channel retrieves relevant
updates for the survey data. This should avoid that the bss channel survey
request times out too often.

Tested on QCA988x hw2.0 10.2.4-1.0-00043

Signed-off-by: Sven Eckelmann <seckelmann@datto.com>
---
 drivers/net/wireless/ath/ath10k/core.c |  8 ++++
 drivers/net/wireless/ath/ath10k/core.h |  1 +
 drivers/net/wireless/ath/ath10k/mac.c  | 52 ++++++++++++++++++++++++++
 drivers/net/wireless/ath/ath10k/mac.h  |  3 ++
 4 files changed, 64 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c
index dc45d16e8d21..754c46047b15 100644
--- a/drivers/net/wireless/ath/ath10k/core.c
+++ b/drivers/net/wireless/ath/ath10k/core.c
@@ -2788,8 +2788,14 @@ int ath10k_core_start(struct ath10k *ar, enum ath10k_firmware_mode mode,
 		goto err_hif_stop;
 	}
 
+	status = ath10k_survey_start(ar);
+	if (status)
+		goto err_debug_stop;
+
 	return 0;
 
+err_debug_stop:
+	ath10k_debug_stop(ar);
 err_hif_stop:
 	ath10k_hif_stop(ar);
 err_htt_rx_detach:
@@ -2829,6 +2835,7 @@ int ath10k_wait_for_suspend(struct ath10k *ar, u32 suspend_opt)
 void ath10k_core_stop(struct ath10k *ar)
 {
 	lockdep_assert_held(&ar->conf_mutex);
+	ath10k_survey_stop(ar);
 	ath10k_debug_stop(ar);
 
 	/* try to suspend target */
@@ -3179,6 +3186,7 @@ struct ath10k *ath10k_core_create(size_t priv_size, struct device *dev,
 	init_completion(&ar->peer_delete_done);
 
 	INIT_DELAYED_WORK(&ar->scan.timeout, ath10k_scan_timeout_work);
+	INIT_DELAYED_WORK(&ar->survey_dwork, ath10k_survey_dwork);
 
 	ar->workqueue = create_singlethread_workqueue("ath10k_wq");
 	if (!ar->workqueue)
diff --git a/drivers/net/wireless/ath/ath10k/core.h b/drivers/net/wireless/ath/ath10k/core.h
index 25c699f3a73b..66d2a1263898 100644
--- a/drivers/net/wireless/ath/ath10k/core.h
+++ b/drivers/net/wireless/ath/ath10k/core.h
@@ -1129,6 +1129,7 @@ struct ath10k {
 	struct survey_info survey[ATH10K_NUM_CHANS];
 	u64 survey_last_total_cc[ATH10K_NUM_CHANS];
 	u64 survey_last_busy_cc[ATH10K_NUM_CHANS];
+	struct delayed_work survey_dwork;
 
 	/* Channel info events are expected to come in pairs without and with
 	 * COMPLETE flag set respectively for each channel visit during scan.
diff --git a/drivers/net/wireless/ath/ath10k/mac.c b/drivers/net/wireless/ath/ath10k/mac.c
index 12dad659bf68..4190b0148e97 100644
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -24,6 +24,9 @@
 #include "wmi-ops.h"
 #include "wow.h"
 
+/* ms */
+#define ATH10K_SURVEY_INTERVAL 10000
+
 /*********/
 /* Rates */
 /*********/
@@ -7152,6 +7155,55 @@ ath10k_mac_update_bss_chan_survey(struct ath10k *ar,
 	}
 }
 
+static void ath10k_request_survey(struct ath10k *ar)
+{
+	lockdep_assert_held(&ar->conf_mutex);
+
+	if (ar->state != ATH10K_STATE_ON)
+		return;
+
+	if (!ar->rx_channel)
+		return;
+
+	ath10k_mac_update_bss_chan_survey(ar, ar->rx_channel);
+}
+
+void ath10k_survey_dwork(struct work_struct *work)
+{
+	struct ath10k *ar = container_of(work, struct ath10k,
+					 survey_dwork.work);
+
+	mutex_lock(&ar->conf_mutex);
+	ath10k_request_survey(ar);
+	mutex_unlock(&ar->conf_mutex);
+
+	queue_delayed_work(ar->workqueue, &ar->survey_dwork,
+			   msecs_to_jiffies(ATH10K_SURVEY_INTERVAL));
+}
+
+int ath10k_survey_start(struct ath10k *ar)
+{
+	lockdep_assert_held(&ar->conf_mutex);
+
+	if (ar->hw_params.cc_wraparound_type != ATH10K_HW_CC_WRAP_SHIFTED_ALL)
+		return 0;
+
+	queue_delayed_work(ar->workqueue, &ar->survey_dwork,
+			   msecs_to_jiffies(ATH10K_SURVEY_INTERVAL));
+
+	return 0;
+}
+
+void ath10k_survey_stop(struct ath10k *ar)
+{
+	lockdep_assert_held(&ar->conf_mutex);
+
+	if (ar->hw_params.cc_wraparound_type != ATH10K_HW_CC_WRAP_SHIFTED_ALL)
+		return;
+
+	cancel_delayed_work_sync(&ar->survey_dwork);
+}
+
 static int ath10k_get_survey(struct ieee80211_hw *hw, int idx,
 			     struct survey_info *survey)
 {
diff --git a/drivers/net/wireless/ath/ath10k/mac.h b/drivers/net/wireless/ath/ath10k/mac.h
index 1fe84948b868..17e4d65edbe0 100644
--- a/drivers/net/wireless/ath/ath10k/mac.h
+++ b/drivers/net/wireless/ath/ath10k/mac.h
@@ -40,6 +40,9 @@ void ath10k_offchan_tx_purge(struct ath10k *ar);
 void ath10k_offchan_tx_work(struct work_struct *work);
 void ath10k_mgmt_over_wmi_tx_purge(struct ath10k *ar);
 void ath10k_mgmt_over_wmi_tx_work(struct work_struct *work);
+void ath10k_survey_dwork(struct work_struct *work);
+int ath10k_survey_start(struct ath10k *ar);
+void ath10k_survey_stop(struct ath10k *ar);
 void ath10k_halt(struct ath10k *ar);
 void ath10k_mac_vif_beacon_free(struct ath10k_vif *arvif);
 void ath10k_drain_tx(struct ath10k *ar);
-- 
2.20.1