iwlwifi: mvm: Add support for RRM by scan

Implement support for RRM by adding an option to configure the scan
dwell time and reporting scan start time and BSS detection time, and
Advertise support for these features.
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/iwl-fw-file.h

@@ -256,6 +256,10 @@ typedef unsigned int __bitwise__ iwl_ucode_tlv_api_t;
  *	instead of 3.
  * @IWL_UCODE_TLV_API_TX_POWER_CHAIN: TX power API has larger command size
  *	(command version 3) that supports per-chain limits
+ * @IWL_UCODE_TLV_API_SCAN_TSF_REPORT: Scan start time reported in scan
+ *	iteration complete notification, and the timestamp reported for RX
+ *	received during scan, are reported in TSF of the mac specified in the
+ *	scan request.
  *
  * @NUM_IWL_UCODE_TLV_API: number of bits used
  */
@@ -267,6 +271,7 @@ enum iwl_ucode_tlv_api {
 	IWL_UCODE_TLV_API_NEW_VERSION           = (__force iwl_ucode_tlv_api_t)20,
 	IWL_UCODE_TLV_API_EXT_SCAN_PRIORITY	= (__force iwl_ucode_tlv_api_t)24,
 	IWL_UCODE_TLV_API_TX_POWER_CHAIN	= (__force iwl_ucode_tlv_api_t)27,
+	IWL_UCODE_TLV_API_SCAN_TSF_REPORT	= (__force iwl_ucode_tlv_api_t)28,
 
 	NUM_IWL_UCODE_TLV_API
 #ifdef __CHECKER__

drivers/net/wireless/intel/iwlwifi/mvm/fw-api-scan.h

@@ -7,6 +7,7 @@
  *
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
+ * Copyright(c) 2016 Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -603,6 +604,8 @@ struct iwl_scan_req_umac_tail {
  * @uid: scan id, &enum iwl_umac_scan_uid_offsets
  * @ooc_priority: out of channel priority - &enum iwl_scan_priority
  * @general_flags: &enum iwl_umac_scan_general_flags
+ * @reserved2: for future use and alignment
+ * @scan_start_mac_id: report the scan start TSF time according to this mac TSF
  * @extended_dwell: dwell time for channels 1, 6 and 11
  * @active_dwell: dwell time for active scan
  * @passive_dwell: dwell time for passive scan
@@ -620,8 +623,10 @@ struct iwl_scan_req_umac {
 	__le32 flags;
 	__le32 uid;
 	__le32 ooc_priority;
-	/* SCAN_GENERAL_PARAMS_API_S_VER_1 */
-	__le32 general_flags;
+	/* SCAN_GENERAL_PARAMS_API_S_VER_4 */
+	__le16 general_flags;
+	u8 reserved2;
+	u8 scan_start_mac_id;
 	u8 extended_dwell;
 	u8 active_dwell;
 	u8 passive_dwell;
@@ -629,7 +634,7 @@ struct iwl_scan_req_umac {
 	__le32 max_out_time;
 	__le32 suspend_time;
 	__le32 scan_priority;
-	/* SCAN_CHANNEL_PARAMS_API_S_VER_1 */
+	/* SCAN_CHANNEL_PARAMS_API_S_VER_4 */
 	u8 channel_flags;
 	u8 n_channels;
 	__le16 reserved;
@@ -718,8 +723,8 @@ struct iwl_scan_offload_profiles_query {
  * @status: one of SCAN_COMP_STATUS_*
  * @bt_status: BT on/off status
  * @last_channel: last channel that was scanned
- * @tsf_low: TSF timer (lower half) in usecs
- * @tsf_high: TSF timer (higher half) in usecs
+ * @start_tsf: TSF timer in usecs of the scan start time for the mac specified
+ *	in &struct iwl_scan_req_umac.
  * @results: array of scan results, only "scanned_channels" of them are valid
  */
 struct iwl_umac_scan_iter_complete_notif {
@@ -728,9 +733,8 @@ struct iwl_umac_scan_iter_complete_notif {
 	u8 status;
 	u8 bt_status;
 	u8 last_channel;
-	__le32 tsf_low;
-	__le32 tsf_high;
+	__le64 start_tsf;
 	struct iwl_scan_results_notif results[];
-} __packed; /* SCAN_ITER_COMPLETE_NTF_UMAC_API_S_VER_1 */
+} __packed; /* SCAN_ITER_COMPLETE_NTF_UMAC_API_S_VER_2 */
 
 #endif

drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c

@@ -653,6 +653,16 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
 			IWL_UCODE_TLV_CAPA_WFA_TPC_REP_IE_SUPPORT))
 		hw->wiphy->features |= NL80211_FEATURE_WFA_TPC_IE_IN_PROBES;
 
+	if (fw_has_api(&mvm->fw->ucode_capa,
+		       IWL_UCODE_TLV_API_SCAN_TSF_REPORT)) {
+		wiphy_ext_feature_set(hw->wiphy,
+				      NL80211_EXT_FEATURE_SCAN_START_TIME);
+		wiphy_ext_feature_set(hw->wiphy,
+				      NL80211_EXT_FEATURE_BSS_PARENT_TSF);
+		wiphy_ext_feature_set(hw->wiphy,
+				      NL80211_EXT_FEATURE_SET_SCAN_DWELL);
+	}
+
 	mvm->rts_threshold = IEEE80211_MAX_RTS_THRESHOLD;
 
 #ifdef CONFIG_PM_SLEEP

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

@@ -821,6 +821,12 @@ struct iwl_mvm {
 	/* UMAC scan tracking */
 	u32 scan_uid_status[IWL_MVM_MAX_UMAC_SCANS];
 
+	/* start time of last scan in TSF of the mac that requested the scan */
+	u64 scan_start;
+
+	/* the vif that requested the current scan */
+	struct iwl_mvm_vif *scan_vif;
+
 	/* rx chain antennas set through debugfs for the scan command */
 	u8 scan_rx_ant;
 

drivers/net/wireless/intel/iwlwifi/mvm/scan.c

@@ -141,6 +141,7 @@ struct iwl_mvm_scan_params {
 	struct cfg80211_match_set *match_sets;
 	int n_scan_plans;
 	struct cfg80211_sched_scan_plan *scan_plans;
+	u32 measurement_dwell;
 };
 
 static u8 iwl_mvm_scan_rx_ant(struct iwl_mvm *mvm)
@@ -232,6 +233,27 @@ iwl_mvm_scan_type iwl_mvm_get_scan_type(struct iwl_mvm *mvm, bool p2p_device)
 	return IWL_SCAN_TYPE_WILD;
 }
 
+static int
+iwl_mvm_get_measurement_dwell(struct iwl_mvm *mvm,
+			      struct cfg80211_scan_request *req,
+			      struct iwl_mvm_scan_params *params)
+{
+	if (!req->duration)
+		return 0;
+
+	if (req->duration_mandatory &&
+	    req->duration > scan_timing[params->type].max_out_time) {
+		IWL_DEBUG_SCAN(mvm,
+			       "Measurement scan - too long dwell %hu (max out time %u)\n",
+			       req->duration,
+			       scan_timing[params->type].max_out_time);
+		return -EOPNOTSUPP;
+	}
+
+	return min_t(u32, (u32)req->duration,
+		     scan_timing[params->type].max_out_time);
+}
+
 static inline bool iwl_mvm_rrm_scan_needed(struct iwl_mvm *mvm)
 {
 	/* require rrm scan whenever the fw supports it */
@@ -1033,9 +1055,15 @@ static void iwl_mvm_scan_umac_dwell(struct iwl_mvm *mvm,
 				    struct iwl_scan_req_umac *cmd,
 				    struct iwl_mvm_scan_params *params)
 {
-	cmd->extended_dwell = scan_timing[params->type].dwell_extended;
-	cmd->active_dwell = scan_timing[params->type].dwell_active;
-	cmd->passive_dwell = scan_timing[params->type].dwell_passive;
+	if (params->measurement_dwell) {
+		cmd->active_dwell = params->measurement_dwell;
+		cmd->passive_dwell = params->measurement_dwell;
+		cmd->extended_dwell = params->measurement_dwell;
+	} else {
+		cmd->active_dwell = scan_timing[params->type].dwell_active;
+		cmd->passive_dwell = scan_timing[params->type].dwell_passive;
+		cmd->extended_dwell = scan_timing[params->type].dwell_extended;
+	}
 	cmd->fragmented_dwell = scan_timing[params->type].dwell_fragmented;
 	cmd->max_out_time = cpu_to_le32(scan_timing[params->type].max_out_time);
 	cmd->suspend_time = cpu_to_le32(scan_timing[params->type].suspend_time);
@@ -1067,11 +1095,11 @@ iwl_mvm_umac_scan_cfg_channels(struct iwl_mvm *mvm,
 	}
 }
 
-static u32 iwl_mvm_scan_umac_flags(struct iwl_mvm *mvm,
+static u16 iwl_mvm_scan_umac_flags(struct iwl_mvm *mvm,
 				   struct iwl_mvm_scan_params *params,
 				   struct ieee80211_vif *vif)
 {
-	int flags = 0;
+	u16 flags = 0;
 
 	if (params->n_ssids == 0)
 		flags = IWL_UMAC_SCAN_GEN_FLAGS_PASSIVE;
@@ -1093,6 +1121,9 @@ static u32 iwl_mvm_scan_umac_flags(struct iwl_mvm *mvm,
 	if (!iwl_mvm_is_regular_scan(params))
 		flags |= IWL_UMAC_SCAN_GEN_FLAGS_PERIODIC;
 
+	if (params->measurement_dwell)
+		flags |= IWL_UMAC_SCAN_GEN_FLAGS_ITER_COMPLETE;
+
 #ifdef CONFIG_IWLWIFI_DEBUGFS
 	if (mvm->scan_iter_notif_enabled)
 		flags |= IWL_UMAC_SCAN_GEN_FLAGS_ITER_COMPLETE;
@@ -1119,6 +1150,7 @@ static int iwl_mvm_scan_umac(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 			mvm->fw->ucode_capa.n_scan_channels;
 	int uid, i;
 	u32 ssid_bitmap = 0;
+	struct iwl_mvm_vif *scan_vif = iwl_mvm_vif_from_mac80211(vif);
 
 	lockdep_assert_held(&mvm->mutex);
 
@@ -1136,8 +1168,9 @@ static int iwl_mvm_scan_umac(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 	mvm->scan_uid_status[uid] = type;
 
 	cmd->uid = cpu_to_le32(uid);
-	cmd->general_flags = cpu_to_le32(iwl_mvm_scan_umac_flags(mvm, params,
+	cmd->general_flags = cpu_to_le16(iwl_mvm_scan_umac_flags(mvm, params,
 								 vif));
+	cmd->scan_start_mac_id = scan_vif->id;
 
 	if (type == IWL_MVM_SCAN_SCHED || type == IWL_MVM_SCAN_NETDETECT)
 		cmd->flags = cpu_to_le32(IWL_UMAC_SCAN_FLAG_PREEMPTIVE);
@@ -1289,6 +1322,12 @@ int iwl_mvm_reg_scan_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 		iwl_mvm_get_scan_type(mvm,
 				      vif->type == NL80211_IFTYPE_P2P_DEVICE);
 
+	ret = iwl_mvm_get_measurement_dwell(mvm, req, &params);
+	if (ret < 0)
+		return ret;
+
+	params.measurement_dwell = ret;
+
 	iwl_mvm_build_scan_probe(mvm, vif, ies, &params);
 
 	if (fw_has_capa(&mvm->fw->ucode_capa, IWL_UCODE_TLV_CAPA_UMAC_SCAN)) {
@@ -1315,6 +1354,7 @@ int iwl_mvm_reg_scan_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 
 	IWL_DEBUG_SCAN(mvm, "Scan request was sent successfully\n");
 	mvm->scan_status |= IWL_MVM_SCAN_REGULAR;
+	mvm->scan_vif = iwl_mvm_vif_from_mac80211(vif);
 	iwl_mvm_ref(mvm, IWL_MVM_REF_SCAN);
 
 	queue_delayed_work(system_wq, &mvm->scan_timeout_dwork,
@@ -1437,9 +1477,12 @@ void iwl_mvm_rx_umac_scan_complete_notif(struct iwl_mvm *mvm,
 	if (mvm->scan_uid_status[uid] == IWL_MVM_SCAN_REGULAR) {
 		struct cfg80211_scan_info info = {
 			.aborted = aborted,
+			.scan_start_tsf = mvm->scan_start,
 		};
 
+		memcpy(info.tsf_bssid, mvm->scan_vif->bssid, ETH_ALEN);
 		ieee80211_scan_completed(mvm->hw, &info);
+		mvm->scan_vif = NULL;
 		iwl_mvm_unref(mvm, IWL_MVM_REF_SCAN);
 		cancel_delayed_work(&mvm->scan_timeout_dwork);
 	} else if (mvm->scan_uid_status[uid] == IWL_MVM_SCAN_SCHED) {
@@ -1473,6 +1516,8 @@ void iwl_mvm_rx_umac_scan_iter_complete_notif(struct iwl_mvm *mvm,
 	struct iwl_umac_scan_iter_complete_notif *notif = (void *)pkt->data;
 	u8 buf[256];
 
+	mvm->scan_start = le64_to_cpu(notif->start_tsf);
+
 	IWL_DEBUG_SCAN(mvm,
 		       "UMAC Scan iteration complete: status=0x%x scanned_channels=%d channels list: %s\n",
 		       notif->status, notif->scanned_channels,
@@ -1485,6 +1530,10 @@ void iwl_mvm_rx_umac_scan_iter_complete_notif(struct iwl_mvm *mvm,
 		ieee80211_sched_scan_results(mvm->hw);
 		mvm->sched_scan_pass_all = SCHED_SCAN_PASS_ALL_ENABLED;
 	}
+
+	IWL_DEBUG_SCAN(mvm,
+		       "UMAC Scan iteration complete: scan started at %llu (TSF)\n",
+		       mvm->scan_start);
 }
 
 static int iwl_mvm_umac_scan_abort(struct iwl_mvm *mvm, int type)