xref: /openbmc/linux/net/mac80211/vht.c (revision 8684014d)
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 	/* don't support VHT for TDLS peers for now */
133 	if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
134 		return;
135 
136 	/*
137 	 * A VHT STA must support 40 MHz, but if we verify that here
138 	 * then we break a few things - some APs (e.g. Netgear R6300v2
139 	 * and others based on the BCM4360 chipset) will unset this
140 	 * capability bit when operating in 20 MHz.
141 	 */
142 
143 	vht_cap->vht_supported = true;
144 
145 	own_cap = sband->vht_cap;
146 	/*
147 	 * If user has specified capability overrides, take care
148 	 * of that if the station we're setting up is the AP that
149 	 * we advertised a restricted capability set to. Override
150 	 * our own capabilities and then use those below.
151 	 */
152 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
153 	    !test_sta_flag(sta, WLAN_STA_TDLS_PEER))
154 		ieee80211_apply_vhtcap_overrides(sdata, &own_cap);
155 
156 	/* take some capabilities as-is */
157 	cap_info = le32_to_cpu(vht_cap_ie->vht_cap_info);
158 	vht_cap->cap = cap_info;
159 	vht_cap->cap &= IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_3895 |
160 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_7991 |
161 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454 |
162 			IEEE80211_VHT_CAP_RXLDPC |
163 			IEEE80211_VHT_CAP_VHT_TXOP_PS |
164 			IEEE80211_VHT_CAP_HTC_VHT |
165 			IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK |
166 			IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_UNSOL_MFB |
167 			IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_MRQ_MFB |
168 			IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN |
169 			IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN;
170 
171 	/* and some based on our own capabilities */
172 	switch (own_cap.cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
173 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
174 		vht_cap->cap |= cap_info &
175 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
176 		break;
177 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
178 		vht_cap->cap |= cap_info &
179 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
180 		break;
181 	default:
182 		/* nothing */
183 		break;
184 	}
185 
186 	/* symmetric capabilities */
187 	vht_cap->cap |= cap_info & own_cap.cap &
188 			(IEEE80211_VHT_CAP_SHORT_GI_80 |
189 			 IEEE80211_VHT_CAP_SHORT_GI_160);
190 
191 	/* remaining ones */
192 	if (own_cap.cap & IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE)
193 		vht_cap->cap |= cap_info &
194 				(IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE |
195 				 IEEE80211_VHT_CAP_SOUNDING_DIMENSIONS_MASK);
196 
197 	if (own_cap.cap & IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE)
198 		vht_cap->cap |= cap_info &
199 				(IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE |
200 				 IEEE80211_VHT_CAP_BEAMFORMEE_STS_MASK);
201 
202 	if (own_cap.cap & IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE)
203 		vht_cap->cap |= cap_info &
204 				IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE;
205 
206 	if (own_cap.cap & IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE)
207 		vht_cap->cap |= cap_info &
208 				IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE;
209 
210 	if (own_cap.cap & IEEE80211_VHT_CAP_TXSTBC)
211 		vht_cap->cap |= cap_info & IEEE80211_VHT_CAP_RXSTBC_MASK;
212 
213 	if (own_cap.cap & IEEE80211_VHT_CAP_RXSTBC_MASK)
214 		vht_cap->cap |= cap_info & IEEE80211_VHT_CAP_TXSTBC;
215 
216 	/* Copy peer MCS info, the driver might need them. */
217 	memcpy(&vht_cap->vht_mcs, &vht_cap_ie->supp_mcs,
218 	       sizeof(struct ieee80211_vht_mcs_info));
219 
220 	/* but also restrict MCSes */
221 	for (i = 0; i < 8; i++) {
222 		u16 own_rx, own_tx, peer_rx, peer_tx;
223 
224 		own_rx = le16_to_cpu(own_cap.vht_mcs.rx_mcs_map);
225 		own_rx = (own_rx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
226 
227 		own_tx = le16_to_cpu(own_cap.vht_mcs.tx_mcs_map);
228 		own_tx = (own_tx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
229 
230 		peer_rx = le16_to_cpu(vht_cap->vht_mcs.rx_mcs_map);
231 		peer_rx = (peer_rx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
232 
233 		peer_tx = le16_to_cpu(vht_cap->vht_mcs.tx_mcs_map);
234 		peer_tx = (peer_tx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
235 
236 		if (peer_tx != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
237 			if (own_rx == IEEE80211_VHT_MCS_NOT_SUPPORTED)
238 				peer_tx = IEEE80211_VHT_MCS_NOT_SUPPORTED;
239 			else if (own_rx < peer_tx)
240 				peer_tx = own_rx;
241 		}
242 
243 		if (peer_rx != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
244 			if (own_tx == IEEE80211_VHT_MCS_NOT_SUPPORTED)
245 				peer_rx = IEEE80211_VHT_MCS_NOT_SUPPORTED;
246 			else if (own_tx < peer_rx)
247 				peer_rx = own_tx;
248 		}
249 
250 		vht_cap->vht_mcs.rx_mcs_map &=
251 			~cpu_to_le16(IEEE80211_VHT_MCS_NOT_SUPPORTED << i * 2);
252 		vht_cap->vht_mcs.rx_mcs_map |= cpu_to_le16(peer_rx << i * 2);
253 
254 		vht_cap->vht_mcs.tx_mcs_map &=
255 			~cpu_to_le16(IEEE80211_VHT_MCS_NOT_SUPPORTED << i * 2);
256 		vht_cap->vht_mcs.tx_mcs_map |= cpu_to_le16(peer_tx << i * 2);
257 	}
258 
259 	/* finally set up the bandwidth */
260 	switch (vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
261 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
262 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
263 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
264 		break;
265 	default:
266 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
267 	}
268 
269 	sta->sta.bandwidth = ieee80211_sta_cur_vht_bw(sta);
270 }
271 
272 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
273 {
274 	struct ieee80211_sub_if_data *sdata = sta->sdata;
275 	u32 cap = sta->sta.vht_cap.cap;
276 	enum ieee80211_sta_rx_bandwidth bw;
277 
278 	if (!sta->sta.vht_cap.vht_supported) {
279 		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
280 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
281 		goto check_max;
282 	}
283 
284 	switch (sdata->vif.bss_conf.chandef.width) {
285 	default:
286 		WARN_ON_ONCE(1);
287 		/* fall through */
288 	case NL80211_CHAN_WIDTH_20_NOHT:
289 	case NL80211_CHAN_WIDTH_20:
290 		bw = IEEE80211_STA_RX_BW_20;
291 		break;
292 	case NL80211_CHAN_WIDTH_40:
293 		bw = sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
294 				IEEE80211_STA_RX_BW_40 : IEEE80211_STA_RX_BW_20;
295 		break;
296 	case NL80211_CHAN_WIDTH_160:
297 		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
298 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ) {
299 			bw = IEEE80211_STA_RX_BW_160;
300 			break;
301 		}
302 		/* fall through */
303 	case NL80211_CHAN_WIDTH_80P80:
304 		if ((cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) ==
305 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ) {
306 			bw = IEEE80211_STA_RX_BW_160;
307 			break;
308 		}
309 		/* fall through */
310 	case NL80211_CHAN_WIDTH_80:
311 		bw = IEEE80211_STA_RX_BW_80;
312 	}
313 
314  check_max:
315 	if (bw > sta->cur_max_bandwidth)
316 		bw = sta->cur_max_bandwidth;
317 	return bw;
318 }
319 
320 void ieee80211_sta_set_rx_nss(struct sta_info *sta)
321 {
322 	u8 ht_rx_nss = 0, vht_rx_nss = 0;
323 
324 	/* if we received a notification already don't overwrite it */
325 	if (sta->sta.rx_nss)
326 		return;
327 
328 	if (sta->sta.ht_cap.ht_supported) {
329 		if (sta->sta.ht_cap.mcs.rx_mask[0])
330 			ht_rx_nss++;
331 		if (sta->sta.ht_cap.mcs.rx_mask[1])
332 			ht_rx_nss++;
333 		if (sta->sta.ht_cap.mcs.rx_mask[2])
334 			ht_rx_nss++;
335 		if (sta->sta.ht_cap.mcs.rx_mask[3])
336 			ht_rx_nss++;
337 		/* FIXME: consider rx_highest? */
338 	}
339 
340 	if (sta->sta.vht_cap.vht_supported) {
341 		int i;
342 		u16 rx_mcs_map;
343 
344 		rx_mcs_map = le16_to_cpu(sta->sta.vht_cap.vht_mcs.rx_mcs_map);
345 
346 		for (i = 7; i >= 0; i--) {
347 			u8 mcs = (rx_mcs_map >> (2 * i)) & 3;
348 
349 			if (mcs != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
350 				vht_rx_nss = i + 1;
351 				break;
352 			}
353 		}
354 		/* FIXME: consider rx_highest? */
355 	}
356 
357 	ht_rx_nss = max(ht_rx_nss, vht_rx_nss);
358 	sta->sta.rx_nss = max_t(u8, 1, ht_rx_nss);
359 }
360 
361 u32 __ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
362 				  struct sta_info *sta, u8 opmode,
363 				  enum ieee80211_band band, bool nss_only)
364 {
365 	struct ieee80211_local *local = sdata->local;
366 	struct ieee80211_supported_band *sband;
367 	enum ieee80211_sta_rx_bandwidth new_bw;
368 	u32 changed = 0;
369 	u8 nss;
370 
371 	sband = local->hw.wiphy->bands[band];
372 
373 	/* ignore - no support for BF yet */
374 	if (opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_TYPE_BF)
375 		return 0;
376 
377 	nss = opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_MASK;
378 	nss >>= IEEE80211_OPMODE_NOTIF_RX_NSS_SHIFT;
379 	nss += 1;
380 
381 	if (sta->sta.rx_nss != nss) {
382 		sta->sta.rx_nss = nss;
383 		changed |= IEEE80211_RC_NSS_CHANGED;
384 	}
385 
386 	if (nss_only)
387 		return changed;
388 
389 	switch (opmode & IEEE80211_OPMODE_NOTIF_CHANWIDTH_MASK) {
390 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_20MHZ:
391 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_20;
392 		break;
393 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_40MHZ:
394 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_40;
395 		break;
396 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_80MHZ:
397 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
398 		break;
399 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_160MHZ:
400 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
401 		break;
402 	}
403 
404 	new_bw = ieee80211_sta_cur_vht_bw(sta);
405 	if (new_bw != sta->sta.bandwidth) {
406 		sta->sta.bandwidth = new_bw;
407 		changed |= IEEE80211_RC_BW_CHANGED;
408 	}
409 
410 	return changed;
411 }
412 
413 void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
414 				 struct sta_info *sta, u8 opmode,
415 				 enum ieee80211_band band, bool nss_only)
416 {
417 	struct ieee80211_local *local = sdata->local;
418 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
419 
420 	u32 changed = __ieee80211_vht_handle_opmode(sdata, sta, opmode,
421 						    band, nss_only);
422 
423 	if (changed > 0)
424 		rate_control_rate_update(local, sband, sta, changed);
425 }
426