xref: /openbmc/linux/net/mac80211/vht.c (revision 840ef8b7cc584a23c4f9d05352f4dbaf8e56e5ab)
1 /*
2  * VHT handling
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/ieee80211.h>
10 #include <linux/export.h>
11 #include <net/mac80211.h>
12 #include "ieee80211_i.h"
13 #include "rate.h"
14 
15 
16 void
17 ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
18 				    struct ieee80211_supported_band *sband,
19 				    const struct ieee80211_vht_cap *vht_cap_ie,
20 				    struct sta_info *sta)
21 {
22 	struct ieee80211_sta_vht_cap *vht_cap = &sta->sta.vht_cap;
23 
24 	memset(vht_cap, 0, sizeof(*vht_cap));
25 
26 	if (!sta->sta.ht_cap.ht_supported)
27 		return;
28 
29 	if (!vht_cap_ie || !sband->vht_cap.vht_supported)
30 		return;
31 
32 	/* A VHT STA must support 40 MHz */
33 	if (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
34 		return;
35 
36 	vht_cap->vht_supported = true;
37 
38 	vht_cap->cap = le32_to_cpu(vht_cap_ie->vht_cap_info);
39 
40 	/* Copy peer MCS info, the driver might need them. */
41 	memcpy(&vht_cap->vht_mcs, &vht_cap_ie->supp_mcs,
42 	       sizeof(struct ieee80211_vht_mcs_info));
43 
44 	switch (vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
45 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
46 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
47 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
48 		break;
49 	default:
50 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
51 	}
52 
53 	sta->sta.bandwidth = ieee80211_sta_cur_vht_bw(sta);
54 }
55 
56 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
57 {
58 	struct ieee80211_sub_if_data *sdata = sta->sdata;
59 	u32 cap = sta->sta.vht_cap.cap;
60 	enum ieee80211_sta_rx_bandwidth bw;
61 
62 	if (!sta->sta.vht_cap.vht_supported) {
63 		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
64 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
65 		goto check_max;
66 	}
67 
68 	switch (sdata->vif.bss_conf.chandef.width) {
69 	default:
70 		WARN_ON_ONCE(1);
71 		/* fall through */
72 	case NL80211_CHAN_WIDTH_20_NOHT:
73 	case NL80211_CHAN_WIDTH_20:
74 	case NL80211_CHAN_WIDTH_40:
75 		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
76 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
77 		break;
78 	case NL80211_CHAN_WIDTH_160:
79 		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
80 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ) {
81 			bw = IEEE80211_STA_RX_BW_160;
82 			break;
83 		}
84 		/* fall through */
85 	case NL80211_CHAN_WIDTH_80P80:
86 		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
87 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
88 			bw = IEEE80211_STA_RX_BW_160;
89 			break;
90 		}
91 		/* fall through */
92 	case NL80211_CHAN_WIDTH_80:
93 		bw = IEEE80211_STA_RX_BW_80;
94 	}
95 
96  check_max:
97 	if (bw > sta->cur_max_bandwidth)
98 		bw = sta->cur_max_bandwidth;
99 	return bw;
100 }
101 
102 void ieee80211_sta_set_rx_nss(struct sta_info *sta)
103 {
104 	u8 ht_rx_nss = 0, vht_rx_nss = 0;
105 
106 	/* if we received a notification already don't overwrite it */
107 	if (sta->sta.rx_nss)
108 		return;
109 
110 	if (sta->sta.ht_cap.ht_supported) {
111 		if (sta->sta.ht_cap.mcs.rx_mask[0])
112 			ht_rx_nss++;
113 		if (sta->sta.ht_cap.mcs.rx_mask[1])
114 			ht_rx_nss++;
115 		if (sta->sta.ht_cap.mcs.rx_mask[2])
116 			ht_rx_nss++;
117 		if (sta->sta.ht_cap.mcs.rx_mask[3])
118 			ht_rx_nss++;
119 		/* FIXME: consider rx_highest? */
120 	}
121 
122 	if (sta->sta.vht_cap.vht_supported) {
123 		int i;
124 		u16 rx_mcs_map;
125 
126 		rx_mcs_map = le16_to_cpu(sta->sta.vht_cap.vht_mcs.rx_mcs_map);
127 
128 		for (i = 7; i >= 0; i--) {
129 			u8 mcs = (rx_mcs_map >> (2 * i)) & 3;
130 
131 			if (mcs != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
132 				vht_rx_nss = i + 1;
133 				break;
134 			}
135 		}
136 		/* FIXME: consider rx_highest? */
137 	}
138 
139 	ht_rx_nss = max(ht_rx_nss, vht_rx_nss);
140 	sta->sta.rx_nss = max_t(u8, 1, ht_rx_nss);
141 }
142 
143 void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
144 				 struct sta_info *sta, u8 opmode,
145 				 enum ieee80211_band band, bool nss_only)
146 {
147 	struct ieee80211_local *local = sdata->local;
148 	struct ieee80211_supported_band *sband;
149 	enum ieee80211_sta_rx_bandwidth new_bw;
150 	u32 changed = 0;
151 	u8 nss;
152 
153 	sband = local->hw.wiphy->bands[band];
154 
155 	/* ignore - no support for BF yet */
156 	if (opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_TYPE_BF)
157 		return;
158 
159 	nss = opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_MASK;
160 	nss >>= IEEE80211_OPMODE_NOTIF_RX_NSS_SHIFT;
161 	nss += 1;
162 
163 	if (sta->sta.rx_nss != nss) {
164 		sta->sta.rx_nss = nss;
165 		changed |= IEEE80211_RC_NSS_CHANGED;
166 	}
167 
168 	if (nss_only)
169 		goto change;
170 
171 	switch (opmode & IEEE80211_OPMODE_NOTIF_CHANWIDTH_MASK) {
172 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_20MHZ:
173 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_20;
174 		break;
175 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_40MHZ:
176 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_40;
177 		break;
178 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_80MHZ:
179 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
180 		break;
181 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_160MHZ:
182 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
183 		break;
184 	}
185 
186 	new_bw = ieee80211_sta_cur_vht_bw(sta);
187 	if (new_bw != sta->sta.bandwidth) {
188 		sta->sta.bandwidth = new_bw;
189 		changed |= IEEE80211_RC_NSS_CHANGED;
190 	}
191 
192  change:
193 	if (changed)
194 		rate_control_rate_update(local, sband, sta, changed);
195 }
196