xref: /openbmc/linux/net/mac80211/vht.c (revision 12eb4683)
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 static void __check_vhtcap_disable(struct ieee80211_sub_if_data *sdata,
17 				   struct ieee80211_sta_vht_cap *vht_cap,
18 				   u32 flag)
19 {
20 	__le32 le_flag = cpu_to_le32(flag);
21 
22 	if (sdata->u.mgd.vht_capa_mask.vht_cap_info & le_flag &&
23 	    !(sdata->u.mgd.vht_capa.vht_cap_info & le_flag))
24 		vht_cap->cap &= ~flag;
25 }
26 
27 void ieee80211_apply_vhtcap_overrides(struct ieee80211_sub_if_data *sdata,
28 				      struct ieee80211_sta_vht_cap *vht_cap)
29 {
30 	int i;
31 	u16 rxmcs_mask, rxmcs_cap, rxmcs_n, txmcs_mask, txmcs_cap, txmcs_n;
32 
33 	if (!vht_cap->vht_supported)
34 		return;
35 
36 	if (sdata->vif.type != NL80211_IFTYPE_STATION)
37 		return;
38 
39 	__check_vhtcap_disable(sdata, vht_cap,
40 			       IEEE80211_VHT_CAP_RXLDPC);
41 	__check_vhtcap_disable(sdata, vht_cap,
42 			       IEEE80211_VHT_CAP_SHORT_GI_80);
43 	__check_vhtcap_disable(sdata, vht_cap,
44 			       IEEE80211_VHT_CAP_SHORT_GI_160);
45 	__check_vhtcap_disable(sdata, vht_cap,
46 			       IEEE80211_VHT_CAP_TXSTBC);
47 	__check_vhtcap_disable(sdata, vht_cap,
48 			       IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE);
49 	__check_vhtcap_disable(sdata, vht_cap,
50 			       IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE);
51 	__check_vhtcap_disable(sdata, vht_cap,
52 			       IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN);
53 	__check_vhtcap_disable(sdata, vht_cap,
54 			       IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN);
55 
56 	/* Allow user to decrease AMPDU length exponent */
57 	if (sdata->u.mgd.vht_capa_mask.vht_cap_info &
58 	    cpu_to_le32(IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK)) {
59 		u32 cap, n;
60 
61 		n = le32_to_cpu(sdata->u.mgd.vht_capa.vht_cap_info) &
62 			IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK;
63 		n >>= IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_SHIFT;
64 		cap = vht_cap->cap & IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK;
65 		cap >>= IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_SHIFT;
66 
67 		if (n < cap) {
68 			vht_cap->cap &=
69 				~IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK;
70 			vht_cap->cap |=
71 				n << IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_SHIFT;
72 		}
73 	}
74 
75 	/* Allow the user to decrease MCSes */
76 	rxmcs_mask =
77 		le16_to_cpu(sdata->u.mgd.vht_capa_mask.supp_mcs.rx_mcs_map);
78 	rxmcs_n = le16_to_cpu(sdata->u.mgd.vht_capa.supp_mcs.rx_mcs_map);
79 	rxmcs_n &= rxmcs_mask;
80 	rxmcs_cap = le16_to_cpu(vht_cap->vht_mcs.rx_mcs_map);
81 
82 	txmcs_mask =
83 		le16_to_cpu(sdata->u.mgd.vht_capa_mask.supp_mcs.tx_mcs_map);
84 	txmcs_n = le16_to_cpu(sdata->u.mgd.vht_capa.supp_mcs.tx_mcs_map);
85 	txmcs_n &= txmcs_mask;
86 	txmcs_cap = le16_to_cpu(vht_cap->vht_mcs.tx_mcs_map);
87 	for (i = 0; i < 8; i++) {
88 		u8 m, n, c;
89 
90 		m = (rxmcs_mask >> 2*i) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
91 		n = (rxmcs_n >> 2*i) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
92 		c = (rxmcs_cap >> 2*i) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
93 
94 		if (m && ((c != IEEE80211_VHT_MCS_NOT_SUPPORTED && n < c) ||
95 			  n == IEEE80211_VHT_MCS_NOT_SUPPORTED)) {
96 			rxmcs_cap &= ~(3 << 2*i);
97 			rxmcs_cap |= (rxmcs_n & (3 << 2*i));
98 		}
99 
100 		m = (txmcs_mask >> 2*i) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
101 		n = (txmcs_n >> 2*i) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
102 		c = (txmcs_cap >> 2*i) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
103 
104 		if (m && ((c != IEEE80211_VHT_MCS_NOT_SUPPORTED && n < c) ||
105 			  n == IEEE80211_VHT_MCS_NOT_SUPPORTED)) {
106 			txmcs_cap &= ~(3 << 2*i);
107 			txmcs_cap |= (txmcs_n & (3 << 2*i));
108 		}
109 	}
110 	vht_cap->vht_mcs.rx_mcs_map = cpu_to_le16(rxmcs_cap);
111 	vht_cap->vht_mcs.tx_mcs_map = cpu_to_le16(txmcs_cap);
112 }
113 
114 void
115 ieee80211_vht_cap_ie_to_sta_vht_cap(struct ieee80211_sub_if_data *sdata,
116 				    struct ieee80211_supported_band *sband,
117 				    const struct ieee80211_vht_cap *vht_cap_ie,
118 				    struct sta_info *sta)
119 {
120 	struct ieee80211_sta_vht_cap *vht_cap = &sta->sta.vht_cap;
121 	struct ieee80211_sta_vht_cap own_cap;
122 	u32 cap_info, i;
123 
124 	memset(vht_cap, 0, sizeof(*vht_cap));
125 
126 	if (!sta->sta.ht_cap.ht_supported)
127 		return;
128 
129 	if (!vht_cap_ie || !sband->vht_cap.vht_supported)
130 		return;
131 
132 	/* A VHT STA must support 40 MHz */
133 	if (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40))
134 		return;
135 
136 	vht_cap->vht_supported = true;
137 
138 	own_cap = sband->vht_cap;
139 	/*
140 	 * If user has specified capability overrides, take care
141 	 * of that if the station we're setting up is the AP that
142 	 * we advertised a restricted capability set to. Override
143 	 * our own capabilities and then use those below.
144 	 */
145 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
146 	    !test_sta_flag(sta, WLAN_STA_TDLS_PEER))
147 		ieee80211_apply_vhtcap_overrides(sdata, &own_cap);
148 
149 	/* take some capabilities as-is */
150 	cap_info = le32_to_cpu(vht_cap_ie->vht_cap_info);
151 	vht_cap->cap = cap_info;
152 	vht_cap->cap &= IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_3895 |
153 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_7991 |
154 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454 |
155 			IEEE80211_VHT_CAP_RXLDPC |
156 			IEEE80211_VHT_CAP_VHT_TXOP_PS |
157 			IEEE80211_VHT_CAP_HTC_VHT |
158 			IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK |
159 			IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_UNSOL_MFB |
160 			IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_MRQ_MFB |
161 			IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN |
162 			IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN;
163 
164 	/* and some based on our own capabilities */
165 	switch (own_cap.cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
166 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
167 		vht_cap->cap |= cap_info &
168 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
169 		break;
170 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
171 		vht_cap->cap |= cap_info &
172 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
173 		break;
174 	default:
175 		/* nothing */
176 		break;
177 	}
178 
179 	/* symmetric capabilities */
180 	vht_cap->cap |= cap_info & own_cap.cap &
181 			(IEEE80211_VHT_CAP_SHORT_GI_80 |
182 			 IEEE80211_VHT_CAP_SHORT_GI_160);
183 
184 	/* remaining ones */
185 	if (own_cap.cap & IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE) {
186 		vht_cap->cap |= cap_info &
187 				(IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE |
188 				 IEEE80211_VHT_CAP_SOUNDING_DIMENSIONS_MAX);
189 	}
190 
191 	if (own_cap.cap & IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE)
192 		vht_cap->cap |= cap_info &
193 				(IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE |
194 				 IEEE80211_VHT_CAP_BEAMFORMEE_STS_MAX);
195 
196 	if (own_cap.cap & IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE)
197 		vht_cap->cap |= cap_info &
198 				IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE;
199 
200 	if (own_cap.cap & IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE)
201 		vht_cap->cap |= cap_info &
202 				IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE;
203 
204 	if (own_cap.cap & IEEE80211_VHT_CAP_TXSTBC)
205 		vht_cap->cap |= cap_info & IEEE80211_VHT_CAP_RXSTBC_MASK;
206 
207 	if (own_cap.cap & IEEE80211_VHT_CAP_RXSTBC_MASK)
208 		vht_cap->cap |= cap_info & IEEE80211_VHT_CAP_TXSTBC;
209 
210 	/* Copy peer MCS info, the driver might need them. */
211 	memcpy(&vht_cap->vht_mcs, &vht_cap_ie->supp_mcs,
212 	       sizeof(struct ieee80211_vht_mcs_info));
213 
214 	/* but also restrict MCSes */
215 	for (i = 0; i < 8; i++) {
216 		u16 own_rx, own_tx, peer_rx, peer_tx;
217 
218 		own_rx = le16_to_cpu(own_cap.vht_mcs.rx_mcs_map);
219 		own_rx = (own_rx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
220 
221 		own_tx = le16_to_cpu(own_cap.vht_mcs.tx_mcs_map);
222 		own_tx = (own_tx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
223 
224 		peer_rx = le16_to_cpu(vht_cap->vht_mcs.rx_mcs_map);
225 		peer_rx = (peer_rx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
226 
227 		peer_tx = le16_to_cpu(vht_cap->vht_mcs.tx_mcs_map);
228 		peer_tx = (peer_tx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
229 
230 		if (peer_tx != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
231 			if (own_rx == IEEE80211_VHT_MCS_NOT_SUPPORTED)
232 				peer_tx = IEEE80211_VHT_MCS_NOT_SUPPORTED;
233 			else if (own_rx < peer_tx)
234 				peer_tx = own_rx;
235 		}
236 
237 		if (peer_rx != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
238 			if (own_tx == IEEE80211_VHT_MCS_NOT_SUPPORTED)
239 				peer_rx = IEEE80211_VHT_MCS_NOT_SUPPORTED;
240 			else if (own_tx < peer_rx)
241 				peer_rx = own_tx;
242 		}
243 
244 		vht_cap->vht_mcs.rx_mcs_map &=
245 			~cpu_to_le16(IEEE80211_VHT_MCS_NOT_SUPPORTED << i * 2);
246 		vht_cap->vht_mcs.rx_mcs_map |= cpu_to_le16(peer_rx << i * 2);
247 
248 		vht_cap->vht_mcs.tx_mcs_map &=
249 			~cpu_to_le16(IEEE80211_VHT_MCS_NOT_SUPPORTED << i * 2);
250 		vht_cap->vht_mcs.tx_mcs_map |= cpu_to_le16(peer_tx << i * 2);
251 	}
252 
253 	/* finally set up the bandwidth */
254 	switch (vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
255 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
256 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
257 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
258 		break;
259 	default:
260 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
261 	}
262 
263 	sta->sta.bandwidth = ieee80211_sta_cur_vht_bw(sta);
264 }
265 
266 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
267 {
268 	struct ieee80211_sub_if_data *sdata = sta->sdata;
269 	u32 cap = sta->sta.vht_cap.cap;
270 	enum ieee80211_sta_rx_bandwidth bw;
271 
272 	if (!sta->sta.vht_cap.vht_supported) {
273 		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
274 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
275 		goto check_max;
276 	}
277 
278 	switch (sdata->vif.bss_conf.chandef.width) {
279 	default:
280 		WARN_ON_ONCE(1);
281 		/* fall through */
282 	case NL80211_CHAN_WIDTH_20_NOHT:
283 	case NL80211_CHAN_WIDTH_20:
284 	case NL80211_CHAN_WIDTH_40:
285 		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
286 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
287 		break;
288 	case NL80211_CHAN_WIDTH_160:
289 		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
290 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ) {
291 			bw = IEEE80211_STA_RX_BW_160;
292 			break;
293 		}
294 		/* fall through */
295 	case NL80211_CHAN_WIDTH_80P80:
296 		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
297 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
298 			bw = IEEE80211_STA_RX_BW_160;
299 			break;
300 		}
301 		/* fall through */
302 	case NL80211_CHAN_WIDTH_80:
303 		bw = IEEE80211_STA_RX_BW_80;
304 	}
305 
306  check_max:
307 	if (bw > sta->cur_max_bandwidth)
308 		bw = sta->cur_max_bandwidth;
309 	return bw;
310 }
311 
312 void ieee80211_sta_set_rx_nss(struct sta_info *sta)
313 {
314 	u8 ht_rx_nss = 0, vht_rx_nss = 0;
315 
316 	/* if we received a notification already don't overwrite it */
317 	if (sta->sta.rx_nss)
318 		return;
319 
320 	if (sta->sta.ht_cap.ht_supported) {
321 		if (sta->sta.ht_cap.mcs.rx_mask[0])
322 			ht_rx_nss++;
323 		if (sta->sta.ht_cap.mcs.rx_mask[1])
324 			ht_rx_nss++;
325 		if (sta->sta.ht_cap.mcs.rx_mask[2])
326 			ht_rx_nss++;
327 		if (sta->sta.ht_cap.mcs.rx_mask[3])
328 			ht_rx_nss++;
329 		/* FIXME: consider rx_highest? */
330 	}
331 
332 	if (sta->sta.vht_cap.vht_supported) {
333 		int i;
334 		u16 rx_mcs_map;
335 
336 		rx_mcs_map = le16_to_cpu(sta->sta.vht_cap.vht_mcs.rx_mcs_map);
337 
338 		for (i = 7; i >= 0; i--) {
339 			u8 mcs = (rx_mcs_map >> (2 * i)) & 3;
340 
341 			if (mcs != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
342 				vht_rx_nss = i + 1;
343 				break;
344 			}
345 		}
346 		/* FIXME: consider rx_highest? */
347 	}
348 
349 	ht_rx_nss = max(ht_rx_nss, vht_rx_nss);
350 	sta->sta.rx_nss = max_t(u8, 1, ht_rx_nss);
351 }
352 
353 void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
354 				 struct sta_info *sta, u8 opmode,
355 				 enum ieee80211_band band, bool nss_only)
356 {
357 	struct ieee80211_local *local = sdata->local;
358 	struct ieee80211_supported_band *sband;
359 	enum ieee80211_sta_rx_bandwidth new_bw;
360 	u32 changed = 0;
361 	u8 nss;
362 
363 	sband = local->hw.wiphy->bands[band];
364 
365 	/* ignore - no support for BF yet */
366 	if (opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_TYPE_BF)
367 		return;
368 
369 	nss = opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_MASK;
370 	nss >>= IEEE80211_OPMODE_NOTIF_RX_NSS_SHIFT;
371 	nss += 1;
372 
373 	if (sta->sta.rx_nss != nss) {
374 		sta->sta.rx_nss = nss;
375 		changed |= IEEE80211_RC_NSS_CHANGED;
376 	}
377 
378 	if (nss_only)
379 		goto change;
380 
381 	switch (opmode & IEEE80211_OPMODE_NOTIF_CHANWIDTH_MASK) {
382 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_20MHZ:
383 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_20;
384 		break;
385 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_40MHZ:
386 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_40;
387 		break;
388 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_80MHZ:
389 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
390 		break;
391 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_160MHZ:
392 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
393 		break;
394 	}
395 
396 	new_bw = ieee80211_sta_cur_vht_bw(sta);
397 	if (new_bw != sta->sta.bandwidth) {
398 		sta->sta.bandwidth = new_bw;
399 		changed |= IEEE80211_RC_BW_CHANGED;
400 	}
401 
402  change:
403 	if (changed)
404 		rate_control_rate_update(local, sband, sta, changed);
405 }
406