wifi: rtw89: add RNR support for 6 GHz scan

Since 6 GHz band has around 60 channels and more strict rules for
active probing. Reduced neighbor report can be used to reduce the
channels we scan and get specific target BSS info to probe for.

Declare flag WIPHY_FLAG_SPLIT_SCAN_6GHZ so the scan request could be
divided into two portions: legacy bands and 6 GHz bands. So RNR
information from legacy bands could later be used when 6 GHz scan.

When the scan flag NL80211_SCAN_FLAG_COLOCATED_6GHZ is set, cfg80211
will pass down a reduced channel set which contains PSCs and non-PSC
with RNR info received in the 2 GHz/5 GHz band. This reduces the
scan duration by allowing us to only scan for channels in which APs
are currently operating.

Signed-off-by: Po-Hao Huang <phhuang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20230217120007.8835-1-pkshih@realtek.com

1 files changed, 121 insertions, 15 deletions

diff --git a/drivers/net/wireless/realtek/rtw89/fw.c b/drivers/net/wireless/realtek/rtw89/fw.c
index 0b73dc2e9ad7..a88f7974c1d6 100644
--- a/drivers/net/wireless/realtek/rtw89/fw.c
+++ b/drivers/net/wireless/realtek/rtw89/fw.c
@@ -2702,9 +2702,29 @@ static void rtw89_release_pkt_list(struct rtw89_dev *rtwdev)
 	}
 }
 
+static bool rtw89_is_6ghz_wildcard_probe_req(struct rtw89_dev *rtwdev,
+					     struct rtw89_vif *rtwvif,
+					     struct rtw89_pktofld_info *info,
+					     enum nl80211_band band, u8 ssid_idx)
+{
+	struct cfg80211_scan_request *req = rtwvif->scan_req;
+
+	if (band != NL80211_BAND_6GHZ)
+		return false;
+
+	if (req->ssids[ssid_idx].ssid_len) {
+		memcpy(info->ssid, req->ssids[ssid_idx].ssid,
+		       req->ssids[ssid_idx].ssid_len);
+		info->ssid_len = req->ssids[ssid_idx].ssid_len;
+		return false;
+	} else {
+		return true;
+	}
+}
+
 static int rtw89_append_probe_req_ie(struct rtw89_dev *rtwdev,
 				     struct rtw89_vif *rtwvif,
-				     struct sk_buff *skb)
+				     struct sk_buff *skb, u8 ssid_idx)
 {
 	struct rtw89_hw_scan_info *scan_info = &rtwdev->scan_info;
 	struct ieee80211_scan_ies *ies = rtwvif->scan_ies;
@@ -2732,6 +2752,13 @@ static int rtw89_append_probe_req_ie(struct rtw89_dev *rtwdev,
 			goto out;
 		}
 
+		if (rtw89_is_6ghz_wildcard_probe_req(rtwdev, rtwvif, info, band,
+						     ssid_idx)) {
+			kfree_skb(new);
+			kfree(info);
+			goto out;
+		}
+
 		ret = rtw89_fw_h2c_add_pkt_offload(rtwdev, &info->id, new);
 		if (ret) {
 			kfree_skb(new);
@@ -2762,7 +2789,7 @@ static int rtw89_hw_scan_update_probe_req(struct rtw89_dev *rtwdev,
 		if (!skb)
 			return -ENOMEM;
 
-		ret = rtw89_append_probe_req_ie(rtwdev, rtwvif, skb);
+		ret = rtw89_append_probe_req_ie(rtwdev, rtwvif, skb, i);
 		kfree_skb(skb);
 
 		if (ret)
@@ -2772,6 +2799,77 @@ static int rtw89_hw_scan_update_probe_req(struct rtw89_dev *rtwdev,
 	return 0;
 }
 
+static int rtw89_update_6ghz_rnr_chan(struct rtw89_dev *rtwdev,
+				      struct cfg80211_scan_request *req,
+				      struct rtw89_mac_chinfo *ch_info)
+{
+	struct ieee80211_vif *vif = rtwdev->scan_info.scanning_vif;
+	struct list_head *pkt_list = rtwdev->scan_info.pkt_list;
+	struct rtw89_vif *rtwvif = vif_to_rtwvif_safe(vif);
+	struct ieee80211_scan_ies *ies = rtwvif->scan_ies;
+	struct cfg80211_scan_6ghz_params *params;
+	struct rtw89_pktofld_info *info, *tmp;
+	struct ieee80211_hdr *hdr;
+	struct sk_buff *skb;
+	bool found;
+	int ret = 0;
+	u8 i;
+
+	if (!req->n_6ghz_params)
+		return 0;
+
+	for (i = 0; i < req->n_6ghz_params; i++) {
+		params = &req->scan_6ghz_params[i];
+
+		if (req->channels[params->channel_idx]->hw_value !=
+		    ch_info->pri_ch)
+			continue;
+
+		found = false;
+		list_for_each_entry(tmp, &pkt_list[NL80211_BAND_6GHZ], list) {
+			if (ether_addr_equal(tmp->bssid, params->bssid)) {
+				found = true;
+				break;
+			}
+		}
+		if (found)
+			continue;
+
+		skb = ieee80211_probereq_get(rtwdev->hw, rtwvif->mac_addr,
+					     NULL, 0, req->ie_len);
+		skb_put_data(skb, ies->ies[NL80211_BAND_6GHZ], ies->len[NL80211_BAND_6GHZ]);
+		skb_put_data(skb, ies->common_ies, ies->common_ie_len);
+		hdr = (struct ieee80211_hdr *)skb->data;
+		ether_addr_copy(hdr->addr3, params->bssid);
+
+		info = kzalloc(sizeof(*info), GFP_KERNEL);
+		if (!info) {
+			ret = -ENOMEM;
+			kfree_skb(skb);
+			goto out;
+		}
+
+		ret = rtw89_fw_h2c_add_pkt_offload(rtwdev, &info->id, skb);
+		if (ret) {
+			kfree_skb(skb);
+			kfree(info);
+			goto out;
+		}
+
+		ether_addr_copy(info->bssid, params->bssid);
+		info->channel_6ghz = req->channels[params->channel_idx]->hw_value;
+		list_add_tail(&info->list, &rtwdev->scan_info.pkt_list[NL80211_BAND_6GHZ]);
+
+		ch_info->tx_pkt = true;
+		ch_info->period = RTW89_CHANNEL_TIME_6G + RTW89_DWELL_TIME_6G;
+
+		kfree_skb(skb);
+	}
+
+out:
+	return ret;
+}
+
 static void rtw89_hw_scan_add_chan(struct rtw89_dev *rtwdev, int chan_type,
 				   int ssid_num,
 				   struct rtw89_mac_chinfo *ch_info)
@@ -2782,6 +2880,7 @@ static void rtw89_hw_scan_add_chan(struct rtw89_dev *rtwdev, int chan_type,
 	struct cfg80211_scan_request *req = rtwvif->scan_req;
 	struct rtw89_pktofld_info *info;
 	u8 band, probe_count = 0;
+	int ret;
 
 	ch_info->notify_action = RTW89_SCANOFLD_DEBUG_MASK;
 	ch_info->dfs_ch = chan_type == RTW89_CHAN_DFS;
@@ -2793,25 +2892,31 @@ static void rtw89_hw_scan_add_chan(struct rtw89_dev *rtwdev, int chan_type,
 	ch_info->pause_data = false;
 	ch_info->probe_id = RTW89_SCANOFLD_PKT_NONE;
 
+	if (ch_info->ch_band == RTW89_BAND_6G) {
+		if ((ssid_num == 1 && req->ssids[0].ssid_len == 0) ||
+		    !ch_info->is_psc) {
+			ch_info->tx_pkt = false;
+			if (!req->duration_mandatory)
+				ch_info->period -= RTW89_DWELL_TIME_6G;
+		}
+	}
+
+	ret = rtw89_update_6ghz_rnr_chan(rtwdev, req, ch_info);
+	if (ret)
+		rtw89_warn(rtwdev, "RNR fails: %d\n", ret);
+
 	if (ssid_num) {
-		ch_info->num_pkt = ssid_num;
 		band = rtw89_hw_to_nl80211_band(ch_info->ch_band);
 
 		list_for_each_entry(info, &scan_info->pkt_list[band], list) {
-			ch_info->pkt_id[probe_count] = info->id;
-			if (++probe_count >= ssid_num)
+			if (info->channel_6ghz &&
+			    ch_info->pri_ch != info->channel_6ghz)
+				continue;
+			ch_info->pkt_id[probe_count++] = info->id;
+			if (probe_count >= RTW89_SCANOFLD_MAX_SSID)
 				break;
 		}
-		if (probe_count != ssid_num)
-			rtw89_err(rtwdev, "SSID num differs from list len\n");
-	}
-
-	if (ch_info->ch_band == RTW89_BAND_6G) {
-		if (ssid_num == 1 && req->ssids[0].ssid_len == 0) {
-			ch_info->tx_pkt = false;
-			if (!req->duration_mandatory)
-				ch_info->period -= RTW89_DWELL_TIME_6G;
-		}
+		ch_info->num_pkt = probe_count;
 	}
 
 	switch (chan_type) {
@@ -2872,6 +2977,7 @@ static int rtw89_hw_scan_add_chan_list(struct rtw89_dev *rtwdev,
 		ch_info->central_ch = channel->hw_value;
 		ch_info->pri_ch = channel->hw_value;
 		ch_info->rand_seq_num = random_seq;
+		ch_info->is_psc = cfg80211_channel_is_psc(channel);
 
 		if (channel->flags &
 		    (IEEE80211_CHAN_RADAR | IEEE80211_CHAN_NO_IR))