wifi: iwlwifi: mvm: add primary 80 known for EHT radiotap

Calculate the position of the control channel in the wide channel
based on the chandef, this is used to obtain the value of N in
802.11be D1.5 Table 9-53a in the column PHY MU/MRU index.

To avoid the need to calculate every frame the value, do it once
monitor vif is added.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230305124407.fe9a5b58e241.I291ee480252d098f62d9ec39040284d3e521d88e@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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

@@ -1362,6 +1362,28 @@ static void iwl_mvm_channel_switch_disconnect_wk(struct work_struct *wk)
 	ieee80211_chswitch_done(vif, false);
 }
 
+static u8
+iwl_mvm_chandef_get_primary_80(struct cfg80211_chan_def *chandef)
+{
+	int data_start;
+	int control_start;
+	int bw;
+
+	if (chandef->width == NL80211_CHAN_WIDTH_320)
+		bw = 320;
+	else if (chandef->width == NL80211_CHAN_WIDTH_160)
+		bw = 160;
+	else
+		return 0;
+
+	/* data is bw wide so the start is half the width */
+	data_start = chandef->center_freq1 - bw / 2;
+	/* control is 20Mhz width */
+	control_start = chandef->chan->center_freq - 10;
+
+	return (control_start - data_start) / 80;
+}
+
 static int iwl_mvm_mac_add_interface(struct ieee80211_hw *hw,
 				     struct ieee80211_vif *vif)
 {
@@ -1478,8 +1500,11 @@ static int iwl_mvm_mac_add_interface(struct ieee80211_hw *hw,
 	INIT_DELAYED_WORK(&mvmvif->csa_work,
 			  iwl_mvm_channel_switch_disconnect_wk);
 
-	if (vif->type == NL80211_IFTYPE_MONITOR)
+	if (vif->type == NL80211_IFTYPE_MONITOR) {
 		mvm->monitor_on = true;
+		mvm->monitor_p80 =
+			iwl_mvm_chandef_get_primary_80(&vif->bss_conf.chandef);
+	}
 
 	iwl_mvm_vif_dbgfs_register(mvm, vif);
 

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

@@ -1096,6 +1096,11 @@ struct iwl_mvm {
 
 	/* does a monitor vif exist (only one can exist hence bool) */
 	bool monitor_on;
+	/*
+	 * primary channel position relative to he whole bandwidth,
+	 * in steps of 80 MHz
+	 */
+	u8 monitor_p80;
 
 	/* sniffer data to include in radiotap */
 	__le16 cur_aid;

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

@@ -1695,6 +1695,15 @@ static void iwl_mvm_decode_eht_phy_data(struct iwl_mvm *mvm,
 
 	iwl_mvm_decode_eht_ru(mvm, rx_status, eht);
 
+	/* We only get here in case of IWL_RX_MPDU_PHY_TSF_OVERLOAD is set
+	 * which is on only in case of monitor mode so no need to check monitor
+	 * mode
+	 */
+	eht->known |= cpu_to_le32(IEEE80211_RADIOTAP_EHT_KNOWN_PRIMARY_80);
+	eht->data[1] |=
+		le32_encode_bits(mvm->monitor_p80,
+				 IEEE80211_RADIOTAP_EHT_DATA1_PRIMARY_80);
+
 	usig->common |= cpu_to_le32(IEEE80211_RADIOTAP_EHT_USIG_COMMON_TXOP_KNOWN);
 	if (phy_data->with_data)
 		usig->common |= LE32_DEC_ENC(data0, IWL_RX_PHY_DATA0_EHT_TXOP_DUR_MASK,