xref: /openbmc/linux/net/mac80211/vht.c (revision 827634ad)
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 	/*
133 	 * A VHT STA must support 40 MHz, but if we verify that here
134 	 * then we break a few things - some APs (e.g. Netgear R6300v2
135 	 * and others based on the BCM4360 chipset) will unset this
136 	 * capability bit when operating in 20 MHz.
137 	 */
138 
139 	vht_cap->vht_supported = true;
140 
141 	own_cap = sband->vht_cap;
142 	/*
143 	 * If user has specified capability overrides, take care
144 	 * of that if the station we're setting up is the AP that
145 	 * we advertised a restricted capability set to. Override
146 	 * our own capabilities and then use those below.
147 	 */
148 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
149 	    !test_sta_flag(sta, WLAN_STA_TDLS_PEER))
150 		ieee80211_apply_vhtcap_overrides(sdata, &own_cap);
151 
152 	/* take some capabilities as-is */
153 	cap_info = le32_to_cpu(vht_cap_ie->vht_cap_info);
154 	vht_cap->cap = cap_info;
155 	vht_cap->cap &= IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_3895 |
156 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_7991 |
157 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454 |
158 			IEEE80211_VHT_CAP_RXLDPC |
159 			IEEE80211_VHT_CAP_VHT_TXOP_PS |
160 			IEEE80211_VHT_CAP_HTC_VHT |
161 			IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK |
162 			IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_UNSOL_MFB |
163 			IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_MRQ_MFB |
164 			IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN |
165 			IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN;
166 
167 	/* and some based on our own capabilities */
168 	switch (own_cap.cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
169 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
170 		vht_cap->cap |= cap_info &
171 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
172 		break;
173 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
174 		vht_cap->cap |= cap_info &
175 				IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
176 		break;
177 	default:
178 		/* nothing */
179 		break;
180 	}
181 
182 	/* symmetric capabilities */
183 	vht_cap->cap |= cap_info & own_cap.cap &
184 			(IEEE80211_VHT_CAP_SHORT_GI_80 |
185 			 IEEE80211_VHT_CAP_SHORT_GI_160);
186 
187 	/* remaining ones */
188 	if (own_cap.cap & IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE)
189 		vht_cap->cap |= cap_info &
190 				(IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE |
191 				 IEEE80211_VHT_CAP_SOUNDING_DIMENSIONS_MASK);
192 
193 	if (own_cap.cap & IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE)
194 		vht_cap->cap |= cap_info &
195 				(IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE |
196 				 IEEE80211_VHT_CAP_BEAMFORMEE_STS_MASK);
197 
198 	if (own_cap.cap & IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE)
199 		vht_cap->cap |= cap_info &
200 				IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE;
201 
202 	if (own_cap.cap & IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE)
203 		vht_cap->cap |= cap_info &
204 				IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE;
205 
206 	if (own_cap.cap & IEEE80211_VHT_CAP_TXSTBC)
207 		vht_cap->cap |= cap_info & IEEE80211_VHT_CAP_RXSTBC_MASK;
208 
209 	if (own_cap.cap & IEEE80211_VHT_CAP_RXSTBC_MASK)
210 		vht_cap->cap |= cap_info & IEEE80211_VHT_CAP_TXSTBC;
211 
212 	/* Copy peer MCS info, the driver might need them. */
213 	memcpy(&vht_cap->vht_mcs, &vht_cap_ie->supp_mcs,
214 	       sizeof(struct ieee80211_vht_mcs_info));
215 
216 	/* but also restrict MCSes */
217 	for (i = 0; i < 8; i++) {
218 		u16 own_rx, own_tx, peer_rx, peer_tx;
219 
220 		own_rx = le16_to_cpu(own_cap.vht_mcs.rx_mcs_map);
221 		own_rx = (own_rx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
222 
223 		own_tx = le16_to_cpu(own_cap.vht_mcs.tx_mcs_map);
224 		own_tx = (own_tx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
225 
226 		peer_rx = le16_to_cpu(vht_cap->vht_mcs.rx_mcs_map);
227 		peer_rx = (peer_rx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
228 
229 		peer_tx = le16_to_cpu(vht_cap->vht_mcs.tx_mcs_map);
230 		peer_tx = (peer_tx >> i * 2) & IEEE80211_VHT_MCS_NOT_SUPPORTED;
231 
232 		if (peer_tx != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
233 			if (own_rx == IEEE80211_VHT_MCS_NOT_SUPPORTED)
234 				peer_tx = IEEE80211_VHT_MCS_NOT_SUPPORTED;
235 			else if (own_rx < peer_tx)
236 				peer_tx = own_rx;
237 		}
238 
239 		if (peer_rx != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
240 			if (own_tx == IEEE80211_VHT_MCS_NOT_SUPPORTED)
241 				peer_rx = IEEE80211_VHT_MCS_NOT_SUPPORTED;
242 			else if (own_tx < peer_rx)
243 				peer_rx = own_tx;
244 		}
245 
246 		vht_cap->vht_mcs.rx_mcs_map &=
247 			~cpu_to_le16(IEEE80211_VHT_MCS_NOT_SUPPORTED << i * 2);
248 		vht_cap->vht_mcs.rx_mcs_map |= cpu_to_le16(peer_rx << i * 2);
249 
250 		vht_cap->vht_mcs.tx_mcs_map &=
251 			~cpu_to_le16(IEEE80211_VHT_MCS_NOT_SUPPORTED << i * 2);
252 		vht_cap->vht_mcs.tx_mcs_map |= cpu_to_le16(peer_tx << i * 2);
253 	}
254 
255 	/* finally set up the bandwidth */
256 	switch (vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) {
257 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ:
258 	case IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ:
259 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
260 		break;
261 	default:
262 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
263 	}
264 
265 	sta->sta.bandwidth = ieee80211_sta_cur_vht_bw(sta);
266 }
267 
268 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cap_rx_bw(struct sta_info *sta)
269 {
270 	struct ieee80211_sta_vht_cap *vht_cap = &sta->sta.vht_cap;
271 	u32 cap_width;
272 
273 	if (!vht_cap->vht_supported)
274 		return sta->sta.ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40 ?
275 				IEEE80211_STA_RX_BW_40 :
276 				IEEE80211_STA_RX_BW_20;
277 
278 	cap_width = vht_cap->cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
279 
280 	if (cap_width == IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ ||
281 	    cap_width == IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
282 		return IEEE80211_STA_RX_BW_160;
283 
284 	return IEEE80211_STA_RX_BW_80;
285 }
286 
287 static enum ieee80211_sta_rx_bandwidth
288 ieee80211_chan_width_to_rx_bw(enum nl80211_chan_width width)
289 {
290 	switch (width) {
291 	case NL80211_CHAN_WIDTH_20_NOHT:
292 	case NL80211_CHAN_WIDTH_20:
293 		return IEEE80211_STA_RX_BW_20;
294 	case NL80211_CHAN_WIDTH_40:
295 		return IEEE80211_STA_RX_BW_40;
296 	case NL80211_CHAN_WIDTH_80:
297 		return IEEE80211_STA_RX_BW_80;
298 	case NL80211_CHAN_WIDTH_160:
299 	case NL80211_CHAN_WIDTH_80P80:
300 		return IEEE80211_STA_RX_BW_160;
301 	default:
302 		WARN_ON_ONCE(1);
303 		return IEEE80211_STA_RX_BW_20;
304 	}
305 }
306 
307 enum ieee80211_sta_rx_bandwidth ieee80211_sta_cur_vht_bw(struct sta_info *sta)
308 {
309 	struct ieee80211_sub_if_data *sdata = sta->sdata;
310 	enum ieee80211_sta_rx_bandwidth bw;
311 
312 	bw = ieee80211_chan_width_to_rx_bw(sdata->vif.bss_conf.chandef.width);
313 	bw = min(bw, ieee80211_sta_cap_rx_bw(sta));
314 	bw = min(bw, sta->cur_max_bandwidth);
315 
316 	return bw;
317 }
318 
319 void ieee80211_sta_set_rx_nss(struct sta_info *sta)
320 {
321 	u8 ht_rx_nss = 0, vht_rx_nss = 0;
322 
323 	/* if we received a notification already don't overwrite it */
324 	if (sta->sta.rx_nss)
325 		return;
326 
327 	if (sta->sta.ht_cap.ht_supported) {
328 		if (sta->sta.ht_cap.mcs.rx_mask[0])
329 			ht_rx_nss++;
330 		if (sta->sta.ht_cap.mcs.rx_mask[1])
331 			ht_rx_nss++;
332 		if (sta->sta.ht_cap.mcs.rx_mask[2])
333 			ht_rx_nss++;
334 		if (sta->sta.ht_cap.mcs.rx_mask[3])
335 			ht_rx_nss++;
336 		/* FIXME: consider rx_highest? */
337 	}
338 
339 	if (sta->sta.vht_cap.vht_supported) {
340 		int i;
341 		u16 rx_mcs_map;
342 
343 		rx_mcs_map = le16_to_cpu(sta->sta.vht_cap.vht_mcs.rx_mcs_map);
344 
345 		for (i = 7; i >= 0; i--) {
346 			u8 mcs = (rx_mcs_map >> (2 * i)) & 3;
347 
348 			if (mcs != IEEE80211_VHT_MCS_NOT_SUPPORTED) {
349 				vht_rx_nss = i + 1;
350 				break;
351 			}
352 		}
353 		/* FIXME: consider rx_highest? */
354 	}
355 
356 	ht_rx_nss = max(ht_rx_nss, vht_rx_nss);
357 	sta->sta.rx_nss = max_t(u8, 1, ht_rx_nss);
358 }
359 
360 u32 __ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
361 				  struct sta_info *sta, u8 opmode,
362 				  enum ieee80211_band band, bool nss_only)
363 {
364 	struct ieee80211_local *local = sdata->local;
365 	struct ieee80211_supported_band *sband;
366 	enum ieee80211_sta_rx_bandwidth new_bw;
367 	u32 changed = 0;
368 	u8 nss;
369 
370 	sband = local->hw.wiphy->bands[band];
371 
372 	/* ignore - no support for BF yet */
373 	if (opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_TYPE_BF)
374 		return 0;
375 
376 	nss = opmode & IEEE80211_OPMODE_NOTIF_RX_NSS_MASK;
377 	nss >>= IEEE80211_OPMODE_NOTIF_RX_NSS_SHIFT;
378 	nss += 1;
379 
380 	if (sta->sta.rx_nss != nss) {
381 		sta->sta.rx_nss = nss;
382 		changed |= IEEE80211_RC_NSS_CHANGED;
383 	}
384 
385 	if (nss_only)
386 		return changed;
387 
388 	switch (opmode & IEEE80211_OPMODE_NOTIF_CHANWIDTH_MASK) {
389 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_20MHZ:
390 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_20;
391 		break;
392 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_40MHZ:
393 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_40;
394 		break;
395 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_80MHZ:
396 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_80;
397 		break;
398 	case IEEE80211_OPMODE_NOTIF_CHANWIDTH_160MHZ:
399 		sta->cur_max_bandwidth = IEEE80211_STA_RX_BW_160;
400 		break;
401 	}
402 
403 	new_bw = ieee80211_sta_cur_vht_bw(sta);
404 	if (new_bw != sta->sta.bandwidth) {
405 		sta->sta.bandwidth = new_bw;
406 		changed |= IEEE80211_RC_BW_CHANGED;
407 	}
408 
409 	return changed;
410 }
411 
412 void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
413 				 struct sta_info *sta, u8 opmode,
414 				 enum ieee80211_band band, bool nss_only)
415 {
416 	struct ieee80211_local *local = sdata->local;
417 	struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
418 
419 	u32 changed = __ieee80211_vht_handle_opmode(sdata, sta, opmode,
420 						    band, nss_only);
421 
422 	if (changed > 0)
423 		rate_control_rate_update(local, sband, sta, changed);
424 }
425