xref: /freebsd/sys/net80211/ieee80211_ht.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*-
2  * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #ifdef __FreeBSD__
28 __FBSDID("$FreeBSD$");
29 #endif
30 
31 /*
32  * IEEE 802.11n protocol support.
33  */
34 
35 #include "opt_inet.h"
36 #include "opt_wlan.h"
37 
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/systm.h>
41 #include <sys/endian.h>
42 
43 #include <sys/socket.h>
44 
45 #include <net/if.h>
46 #include <net/if_media.h>
47 #include <net/ethernet.h>
48 
49 #include <net80211/ieee80211_var.h>
50 #include <net80211/ieee80211_action.h>
51 #include <net80211/ieee80211_input.h>
52 
53 /* define here, used throughout file */
54 #define	MS(_v, _f)	(((_v) & _f) >> _f##_S)
55 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
56 
57 const struct ieee80211_mcs_rates ieee80211_htrates[IEEE80211_HTRATE_MAXSIZE] = {
58 	{  13,  14,   27,   30 },	/* MCS 0 */
59 	{  26,  29,   54,   60 },	/* MCS 1 */
60 	{  39,  43,   81,   90 },	/* MCS 2 */
61 	{  52,  58,  108,  120 },	/* MCS 3 */
62 	{  78,  87,  162,  180 },	/* MCS 4 */
63 	{ 104, 116,  216,  240 },	/* MCS 5 */
64 	{ 117, 130,  243,  270 },	/* MCS 6 */
65 	{ 130, 144,  270,  300 },	/* MCS 7 */
66 	{  26,  29,   54,   60 },	/* MCS 8 */
67 	{  52,  58,  108,  120 },	/* MCS 9 */
68 	{  78,  87,  162,  180 },	/* MCS 10 */
69 	{ 104, 116,  216,  240 },	/* MCS 11 */
70 	{ 156, 173,  324,  360 },	/* MCS 12 */
71 	{ 208, 231,  432,  480 },	/* MCS 13 */
72 	{ 234, 260,  486,  540 },	/* MCS 14 */
73 	{ 260, 289,  540,  600 },	/* MCS 15 */
74 	{  39,  43,   81,   90 },	/* MCS 16 */
75 	{  78,  87,  162,  180 },	/* MCS 17 */
76 	{ 117, 130,  243,  270 },	/* MCS 18 */
77 	{ 156, 173,  324,  360 },	/* MCS 19 */
78 	{ 234, 260,  486,  540 },	/* MCS 20 */
79 	{ 312, 347,  648,  720 },	/* MCS 21 */
80 	{ 351, 390,  729,  810 },	/* MCS 22 */
81 	{ 390, 433,  810,  900 },	/* MCS 23 */
82 	{  52,  58,  108,  120 },	/* MCS 24 */
83 	{ 104, 116,  216,  240 },	/* MCS 25 */
84 	{ 156, 173,  324,  360 },	/* MCS 26 */
85 	{ 208, 231,  432,  480 },	/* MCS 27 */
86 	{ 312, 347,  648,  720 },	/* MCS 28 */
87 	{ 416, 462,  864,  960 },	/* MCS 29 */
88 	{ 468, 520,  972, 1080 },	/* MCS 30 */
89 	{ 520, 578, 1080, 1200 },	/* MCS 31 */
90 	{   0,   0,   12,   13 },	/* MCS 32 */
91 	{  78,  87,  162,  180 },	/* MCS 33 */
92 	{ 104, 116,  216,  240 },	/* MCS 34 */
93 	{ 130, 144,  270,  300 },	/* MCS 35 */
94 	{ 117, 130,  243,  270 },	/* MCS 36 */
95 	{ 156, 173,  324,  360 },	/* MCS 37 */
96 	{ 195, 217,  405,  450 },	/* MCS 38 */
97 	{ 104, 116,  216,  240 },	/* MCS 39 */
98 	{ 130, 144,  270,  300 },	/* MCS 40 */
99 	{ 130, 144,  270,  300 },	/* MCS 41 */
100 	{ 156, 173,  324,  360 },	/* MCS 42 */
101 	{ 182, 202,  378,  420 },	/* MCS 43 */
102 	{ 182, 202,  378,  420 },	/* MCS 44 */
103 	{ 208, 231,  432,  480 },	/* MCS 45 */
104 	{ 156, 173,  324,  360 },	/* MCS 46 */
105 	{ 195, 217,  405,  450 },	/* MCS 47 */
106 	{ 195, 217,  405,  450 },	/* MCS 48 */
107 	{ 234, 260,  486,  540 },	/* MCS 49 */
108 	{ 273, 303,  567,  630 },	/* MCS 50 */
109 	{ 273, 303,  567,  630 },	/* MCS 51 */
110 	{ 312, 347,  648,  720 },	/* MCS 52 */
111 	{ 130, 144,  270,  300 },	/* MCS 53 */
112 	{ 156, 173,  324,  360 },	/* MCS 54 */
113 	{ 182, 202,  378,  420 },	/* MCS 55 */
114 	{ 156, 173,  324,  360 },	/* MCS 56 */
115 	{ 182, 202,  378,  420 },	/* MCS 57 */
116 	{ 208, 231,  432,  480 },	/* MCS 58 */
117 	{ 234, 260,  486,  540 },	/* MCS 59 */
118 	{ 208, 231,  432,  480 },	/* MCS 60 */
119 	{ 234, 260,  486,  540 },	/* MCS 61 */
120 	{ 260, 289,  540,  600 },	/* MCS 62 */
121 	{ 260, 289,  540,  600 },	/* MCS 63 */
122 	{ 286, 318,  594,  660 },	/* MCS 64 */
123 	{ 195, 217,  405,  450 },	/* MCS 65 */
124 	{ 234, 260,  486,  540 },	/* MCS 66 */
125 	{ 273, 303,  567,  630 },	/* MCS 67 */
126 	{ 234, 260,  486,  540 },	/* MCS 68 */
127 	{ 273, 303,  567,  630 },	/* MCS 69 */
128 	{ 312, 347,  648,  720 },	/* MCS 70 */
129 	{ 351, 390,  729,  810 },	/* MCS 71 */
130 	{ 312, 347,  648,  720 },	/* MCS 72 */
131 	{ 351, 390,  729,  810 },	/* MCS 73 */
132 	{ 390, 433,  810,  900 },	/* MCS 74 */
133 	{ 390, 433,  810,  900 },	/* MCS 75 */
134 	{ 429, 477,  891,  990 },	/* MCS 76 */
135 };
136 
137 #ifdef IEEE80211_AMPDU_AGE
138 static	int ieee80211_ampdu_age = -1;	/* threshold for ampdu reorder q (ms) */
139 SYSCTL_PROC(_net_wlan, OID_AUTO, ampdu_age, CTLTYPE_INT | CTLFLAG_RW,
140 	&ieee80211_ampdu_age, 0, ieee80211_sysctl_msecs_ticks, "I",
141 	"AMPDU max reorder age (ms)");
142 #endif
143 
144 static	int ieee80211_recv_bar_ena = 1;
145 SYSCTL_INT(_net_wlan, OID_AUTO, recv_bar, CTLFLAG_RW, &ieee80211_recv_bar_ena,
146 	    0, "BAR frame processing (ena/dis)");
147 
148 static	int ieee80211_addba_timeout = -1;/* timeout for ADDBA response */
149 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_timeout, CTLTYPE_INT | CTLFLAG_RW,
150 	&ieee80211_addba_timeout, 0, ieee80211_sysctl_msecs_ticks, "I",
151 	"ADDBA request timeout (ms)");
152 static	int ieee80211_addba_backoff = -1;/* backoff after max ADDBA requests */
153 SYSCTL_PROC(_net_wlan, OID_AUTO, addba_backoff, CTLTYPE_INT | CTLFLAG_RW,
154 	&ieee80211_addba_backoff, 0, ieee80211_sysctl_msecs_ticks, "I",
155 	"ADDBA request backoff (ms)");
156 static	int ieee80211_addba_maxtries = 3;/* max ADDBA requests before backoff */
157 SYSCTL_INT(_net_wlan, OID_AUTO, addba_maxtries, CTLTYPE_INT | CTLFLAG_RW,
158 	&ieee80211_addba_maxtries, 0, "max ADDBA requests sent before backoff");
159 
160 static	int ieee80211_bar_timeout = -1;	/* timeout waiting for BAR response */
161 static	int ieee80211_bar_maxtries = 50;/* max BAR requests before DELBA */
162 
163 static	ieee80211_recv_action_func ht_recv_action_ba_addba_request;
164 static	ieee80211_recv_action_func ht_recv_action_ba_addba_response;
165 static	ieee80211_recv_action_func ht_recv_action_ba_delba;
166 static	ieee80211_recv_action_func ht_recv_action_ht_mimopwrsave;
167 static	ieee80211_recv_action_func ht_recv_action_ht_txchwidth;
168 
169 static	ieee80211_send_action_func ht_send_action_ba_addba;
170 static	ieee80211_send_action_func ht_send_action_ba_delba;
171 static	ieee80211_send_action_func ht_send_action_ht_txchwidth;
172 
173 static void
174 ieee80211_ht_init(void)
175 {
176 	/*
177 	 * Setup HT parameters that depends on the clock frequency.
178 	 */
179 #ifdef IEEE80211_AMPDU_AGE
180 	ieee80211_ampdu_age = msecs_to_ticks(500);
181 #endif
182 	ieee80211_addba_timeout = msecs_to_ticks(250);
183 	ieee80211_addba_backoff = msecs_to_ticks(10*1000);
184 	ieee80211_bar_timeout = msecs_to_ticks(250);
185 	/*
186 	 * Register action frame handlers.
187 	 */
188 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
189 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_recv_action_ba_addba_request);
190 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
191 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_recv_action_ba_addba_response);
192 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_BA,
193 	    IEEE80211_ACTION_BA_DELBA, ht_recv_action_ba_delba);
194 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
195 	    IEEE80211_ACTION_HT_MIMOPWRSAVE, ht_recv_action_ht_mimopwrsave);
196 	ieee80211_recv_action_register(IEEE80211_ACTION_CAT_HT,
197 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_recv_action_ht_txchwidth);
198 
199 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
200 	    IEEE80211_ACTION_BA_ADDBA_REQUEST, ht_send_action_ba_addba);
201 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
202 	    IEEE80211_ACTION_BA_ADDBA_RESPONSE, ht_send_action_ba_addba);
203 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_BA,
204 	    IEEE80211_ACTION_BA_DELBA, ht_send_action_ba_delba);
205 	ieee80211_send_action_register(IEEE80211_ACTION_CAT_HT,
206 	    IEEE80211_ACTION_HT_TXCHWIDTH, ht_send_action_ht_txchwidth);
207 }
208 SYSINIT(wlan_ht, SI_SUB_DRIVERS, SI_ORDER_FIRST, ieee80211_ht_init, NULL);
209 
210 static int ieee80211_ampdu_enable(struct ieee80211_node *ni,
211 	struct ieee80211_tx_ampdu *tap);
212 static int ieee80211_addba_request(struct ieee80211_node *ni,
213 	struct ieee80211_tx_ampdu *tap,
214 	int dialogtoken, int baparamset, int batimeout);
215 static int ieee80211_addba_response(struct ieee80211_node *ni,
216 	struct ieee80211_tx_ampdu *tap,
217 	int code, int baparamset, int batimeout);
218 static void ieee80211_addba_stop(struct ieee80211_node *ni,
219 	struct ieee80211_tx_ampdu *tap);
220 static void ieee80211_bar_response(struct ieee80211_node *ni,
221 	struct ieee80211_tx_ampdu *tap, int status);
222 static void ampdu_tx_stop(struct ieee80211_tx_ampdu *tap);
223 static void bar_stop_timer(struct ieee80211_tx_ampdu *tap);
224 static int ampdu_rx_start(struct ieee80211_node *, struct ieee80211_rx_ampdu *,
225 	int baparamset, int batimeout, int baseqctl);
226 static void ampdu_rx_stop(struct ieee80211_node *, struct ieee80211_rx_ampdu *);
227 
228 void
229 ieee80211_ht_attach(struct ieee80211com *ic)
230 {
231 	/* setup default aggregation policy */
232 	ic->ic_recv_action = ieee80211_recv_action;
233 	ic->ic_send_action = ieee80211_send_action;
234 	ic->ic_ampdu_enable = ieee80211_ampdu_enable;
235 	ic->ic_addba_request = ieee80211_addba_request;
236 	ic->ic_addba_response = ieee80211_addba_response;
237 	ic->ic_addba_stop = ieee80211_addba_stop;
238 	ic->ic_bar_response = ieee80211_bar_response;
239 	ic->ic_ampdu_rx_start = ampdu_rx_start;
240 	ic->ic_ampdu_rx_stop = ampdu_rx_stop;
241 
242 	ic->ic_htprotmode = IEEE80211_PROT_RTSCTS;
243 	ic->ic_curhtprotmode = IEEE80211_HTINFO_OPMODE_PURE;
244 }
245 
246 void
247 ieee80211_ht_detach(struct ieee80211com *ic)
248 {
249 }
250 
251 void
252 ieee80211_ht_vattach(struct ieee80211vap *vap)
253 {
254 
255 	/* driver can override defaults */
256 	vap->iv_ampdu_rxmax = IEEE80211_HTCAP_MAXRXAMPDU_8K;
257 	vap->iv_ampdu_density = IEEE80211_HTCAP_MPDUDENSITY_NA;
258 	vap->iv_ampdu_limit = vap->iv_ampdu_rxmax;
259 	vap->iv_amsdu_limit = vap->iv_htcaps & IEEE80211_HTCAP_MAXAMSDU;
260 	/* tx aggregation traffic thresholds */
261 	vap->iv_ampdu_mintraffic[WME_AC_BK] = 128;
262 	vap->iv_ampdu_mintraffic[WME_AC_BE] = 64;
263 	vap->iv_ampdu_mintraffic[WME_AC_VO] = 32;
264 	vap->iv_ampdu_mintraffic[WME_AC_VI] = 32;
265 
266 	if (vap->iv_htcaps & IEEE80211_HTC_HT) {
267 		/*
268 		 * Device is HT capable; enable all HT-related
269 		 * facilities by default.
270 		 * XXX these choices may be too aggressive.
271 		 */
272 		vap->iv_flags_ht |= IEEE80211_FHT_HT
273 				 |  IEEE80211_FHT_HTCOMPAT
274 				 ;
275 		if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI20)
276 			vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI20;
277 		/* XXX infer from channel list? */
278 		if (vap->iv_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
279 			vap->iv_flags_ht |= IEEE80211_FHT_USEHT40;
280 			if (vap->iv_htcaps & IEEE80211_HTCAP_SHORTGI40)
281 				vap->iv_flags_ht |= IEEE80211_FHT_SHORTGI40;
282 		}
283 		/* enable RIFS if capable */
284 		if (vap->iv_htcaps & IEEE80211_HTC_RIFS)
285 			vap->iv_flags_ht |= IEEE80211_FHT_RIFS;
286 
287 		/* NB: A-MPDU and A-MSDU rx are mandated, these are tx only */
288 		vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_RX;
289 		if (vap->iv_htcaps & IEEE80211_HTC_AMPDU)
290 			vap->iv_flags_ht |= IEEE80211_FHT_AMPDU_TX;
291 		vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_RX;
292 		if (vap->iv_htcaps & IEEE80211_HTC_AMSDU)
293 			vap->iv_flags_ht |= IEEE80211_FHT_AMSDU_TX;
294 	}
295 	/* NB: disable default legacy WDS, too many issues right now */
296 	if (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)
297 		vap->iv_flags_ht &= ~IEEE80211_FHT_HT;
298 }
299 
300 void
301 ieee80211_ht_vdetach(struct ieee80211vap *vap)
302 {
303 }
304 
305 static int
306 ht_getrate(struct ieee80211com *ic, int index, int mode, int ratetype)
307 {
308 	int mword, rate;
309 
310 	mword = ieee80211_rate2media(ic, index | IEEE80211_RATE_MCS, mode);
311 	if (IFM_SUBTYPE(mword) != IFM_IEEE80211_MCS)
312 		return (0);
313 	switch (ratetype) {
314 	case 0:
315 		rate = ieee80211_htrates[index].ht20_rate_800ns;
316 		break;
317 	case 1:
318 		rate = ieee80211_htrates[index].ht20_rate_400ns;
319 		break;
320 	case 2:
321 		rate = ieee80211_htrates[index].ht40_rate_800ns;
322 		break;
323 	default:
324 		rate = ieee80211_htrates[index].ht40_rate_400ns;
325 		break;
326 	}
327 	return (rate);
328 }
329 
330 static struct printranges {
331 	int	minmcs;
332 	int	maxmcs;
333 	int	txstream;
334 	int	ratetype;
335 	int	htcapflags;
336 } ranges[] = {
337 	{  0,  7, 1, 0, 0 },
338 	{  8, 15, 2, 0, 0 },
339 	{ 16, 23, 3, 0, 0 },
340 	{ 24, 31, 4, 0, 0 },
341 	{ 32,  0, 1, 2, IEEE80211_HTC_TXMCS32 },
342 	{ 33, 38, 2, 0, IEEE80211_HTC_TXUNEQUAL },
343 	{ 39, 52, 3, 0, IEEE80211_HTC_TXUNEQUAL },
344 	{ 53, 76, 4, 0, IEEE80211_HTC_TXUNEQUAL },
345 	{  0,  0, 0, 0, 0 },
346 };
347 
348 static void
349 ht_rateprint(struct ieee80211com *ic, int mode, int ratetype)
350 {
351 	struct ifnet *ifp = ic->ic_ifp;
352 	int minrate, maxrate;
353 	struct printranges *range;
354 
355 	for (range = ranges; range->txstream != 0; range++) {
356 		if (ic->ic_txstream < range->txstream)
357 			continue;
358 		if (range->htcapflags &&
359 		    (ic->ic_htcaps & range->htcapflags) == 0)
360 			continue;
361 		if (ratetype < range->ratetype)
362 			continue;
363 		minrate = ht_getrate(ic, range->minmcs, mode, ratetype);
364 		maxrate = ht_getrate(ic, range->maxmcs, mode, ratetype);
365 		if (range->maxmcs) {
366 			if_printf(ifp, "MCS %d-%d: %d%sMbps - %d%sMbps\n",
367 			    range->minmcs, range->maxmcs,
368 			    minrate/2, ((minrate & 0x1) != 0 ? ".5" : ""),
369 			    maxrate/2, ((maxrate & 0x1) != 0 ? ".5" : ""));
370 		} else {
371 			if_printf(ifp, "MCS %d: %d%sMbps\n", range->minmcs,
372 			    minrate/2, ((minrate & 0x1) != 0 ? ".5" : ""));
373 		}
374 	}
375 }
376 
377 static void
378 ht_announce(struct ieee80211com *ic, int mode)
379 {
380 	struct ifnet *ifp = ic->ic_ifp;
381 	const char *modestr = ieee80211_phymode_name[mode];
382 
383 	if_printf(ifp, "%s MCS 20MHz\n", modestr);
384 	ht_rateprint(ic, mode, 0);
385 	if (ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI20) {
386 		if_printf(ifp, "%s MCS 20MHz SGI\n", modestr);
387 		ht_rateprint(ic, mode, 1);
388 	}
389 	if (ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) {
390 		if_printf(ifp, "%s MCS 40MHz:\n", modestr);
391 		ht_rateprint(ic, mode, 2);
392 	}
393 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
394 	    (ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI40)) {
395 		if_printf(ifp, "%s MCS 40MHz SGI:\n", modestr);
396 		ht_rateprint(ic, mode, 3);
397 	}
398 }
399 
400 void
401 ieee80211_ht_announce(struct ieee80211com *ic)
402 {
403 	struct ifnet *ifp = ic->ic_ifp;
404 
405 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA) ||
406 	    isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
407 		if_printf(ifp, "%dT%dR\n", ic->ic_txstream, ic->ic_rxstream);
408 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
409 		ht_announce(ic, IEEE80211_MODE_11NA);
410 	if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
411 		ht_announce(ic, IEEE80211_MODE_11NG);
412 }
413 
414 static struct ieee80211_htrateset htrateset;
415 
416 const struct ieee80211_htrateset *
417 ieee80211_get_suphtrates(struct ieee80211com *ic,
418     const struct ieee80211_channel *c)
419 {
420 #define	ADDRATE(x)	do {						\
421 	htrateset.rs_rates[htrateset.rs_nrates] = x;			\
422 	htrateset.rs_nrates++;						\
423 } while (0)
424 	int i;
425 
426 	memset(&htrateset, 0, sizeof(struct ieee80211_htrateset));
427 	for (i = 0; i < ic->ic_txstream * 8; i++)
428 		ADDRATE(i);
429 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
430 	    (ic->ic_htcaps & IEEE80211_HTC_TXMCS32))
431 		ADDRATE(i);
432 	if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL) {
433 		if (ic->ic_txstream >= 2) {
434 			 for (i = 33; i <= 38; i++)
435 				ADDRATE(i);
436 		}
437 		if (ic->ic_txstream >= 3) {
438 			for (i = 39; i <= 52; i++)
439 				ADDRATE(i);
440 		}
441 		if (ic->ic_txstream == 4) {
442 			for (i = 53; i <= 76; i++)
443 				ADDRATE(i);
444 		}
445 	}
446 	return &htrateset;
447 #undef	ADDRATE
448 }
449 
450 /*
451  * Receive processing.
452  */
453 
454 /*
455  * Decap the encapsulated A-MSDU frames and dispatch all but
456  * the last for delivery.  The last frame is returned for
457  * delivery via the normal path.
458  */
459 struct mbuf *
460 ieee80211_decap_amsdu(struct ieee80211_node *ni, struct mbuf *m)
461 {
462 	struct ieee80211vap *vap = ni->ni_vap;
463 	int framelen;
464 	struct mbuf *n;
465 
466 	/* discard 802.3 header inserted by ieee80211_decap */
467 	m_adj(m, sizeof(struct ether_header));
468 
469 	vap->iv_stats.is_amsdu_decap++;
470 
471 	for (;;) {
472 		/*
473 		 * Decap the first frame, bust it apart from the
474 		 * remainder and deliver.  We leave the last frame
475 		 * delivery to the caller (for consistency with other
476 		 * code paths, could also do it here).
477 		 */
478 		m = ieee80211_decap1(m, &framelen);
479 		if (m == NULL) {
480 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
481 			    ni->ni_macaddr, "a-msdu", "%s", "decap failed");
482 			vap->iv_stats.is_amsdu_tooshort++;
483 			return NULL;
484 		}
485 		if (m->m_pkthdr.len == framelen)
486 			break;
487 		n = m_split(m, framelen, M_NOWAIT);
488 		if (n == NULL) {
489 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
490 			    ni->ni_macaddr, "a-msdu",
491 			    "%s", "unable to split encapsulated frames");
492 			vap->iv_stats.is_amsdu_split++;
493 			m_freem(m);			/* NB: must reclaim */
494 			return NULL;
495 		}
496 		vap->iv_deliver_data(vap, ni, m);
497 
498 		/*
499 		 * Remove frame contents; each intermediate frame
500 		 * is required to be aligned to a 4-byte boundary.
501 		 */
502 		m = n;
503 		m_adj(m, roundup2(framelen, 4) - framelen);	/* padding */
504 	}
505 	return m;				/* last delivered by caller */
506 }
507 
508 /*
509  * Purge all frames in the A-MPDU re-order queue.
510  */
511 static void
512 ampdu_rx_purge(struct ieee80211_rx_ampdu *rap)
513 {
514 	struct mbuf *m;
515 	int i;
516 
517 	for (i = 0; i < rap->rxa_wnd; i++) {
518 		m = rap->rxa_m[i];
519 		if (m != NULL) {
520 			rap->rxa_m[i] = NULL;
521 			rap->rxa_qbytes -= m->m_pkthdr.len;
522 			m_freem(m);
523 			if (--rap->rxa_qframes == 0)
524 				break;
525 		}
526 	}
527 	KASSERT(rap->rxa_qbytes == 0 && rap->rxa_qframes == 0,
528 	    ("lost %u data, %u frames on ampdu rx q",
529 	    rap->rxa_qbytes, rap->rxa_qframes));
530 }
531 
532 /*
533  * Start A-MPDU rx/re-order processing for the specified TID.
534  */
535 static int
536 ampdu_rx_start(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap,
537 	int baparamset, int batimeout, int baseqctl)
538 {
539 	int bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
540 
541 	if (rap->rxa_flags & IEEE80211_AGGR_RUNNING) {
542 		/*
543 		 * AMPDU previously setup and not terminated with a DELBA,
544 		 * flush the reorder q's in case anything remains.
545 		 */
546 		ampdu_rx_purge(rap);
547 	}
548 	memset(rap, 0, sizeof(*rap));
549 	rap->rxa_wnd = (bufsiz == 0) ?
550 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
551 	rap->rxa_start = MS(baseqctl, IEEE80211_BASEQ_START);
552 	rap->rxa_flags |=  IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND;
553 
554 	return 0;
555 }
556 
557 /*
558  * Stop A-MPDU rx processing for the specified TID.
559  */
560 static void
561 ampdu_rx_stop(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
562 {
563 
564 	ampdu_rx_purge(rap);
565 	rap->rxa_flags &= ~(IEEE80211_AGGR_RUNNING | IEEE80211_AGGR_XCHGPEND);
566 }
567 
568 /*
569  * Dispatch a frame from the A-MPDU reorder queue.  The
570  * frame is fed back into ieee80211_input marked with an
571  * M_AMPDU_MPDU flag so it doesn't come back to us (it also
572  * permits ieee80211_input to optimize re-processing).
573  */
574 static __inline void
575 ampdu_dispatch(struct ieee80211_node *ni, struct mbuf *m)
576 {
577 	m->m_flags |= M_AMPDU_MPDU;	/* bypass normal processing */
578 	/* NB: rssi and noise are ignored w/ M_AMPDU_MPDU set */
579 	(void) ieee80211_input(ni, m, 0, 0);
580 }
581 
582 /*
583  * Dispatch as many frames as possible from the re-order queue.
584  * Frames will always be "at the front"; we process all frames
585  * up to the first empty slot in the window.  On completion we
586  * cleanup state if there are still pending frames in the current
587  * BA window.  We assume the frame at slot 0 is already handled
588  * by the caller; we always start at slot 1.
589  */
590 static void
591 ampdu_rx_dispatch(struct ieee80211_rx_ampdu *rap, struct ieee80211_node *ni)
592 {
593 	struct ieee80211vap *vap = ni->ni_vap;
594 	struct mbuf *m;
595 	int i;
596 
597 	/* flush run of frames */
598 	for (i = 1; i < rap->rxa_wnd; i++) {
599 		m = rap->rxa_m[i];
600 		if (m == NULL)
601 			break;
602 		rap->rxa_m[i] = NULL;
603 		rap->rxa_qbytes -= m->m_pkthdr.len;
604 		rap->rxa_qframes--;
605 
606 		ampdu_dispatch(ni, m);
607 	}
608 	/*
609 	 * If frames remain, copy the mbuf pointers down so
610 	 * they correspond to the offsets in the new window.
611 	 */
612 	if (rap->rxa_qframes != 0) {
613 		int n = rap->rxa_qframes, j;
614 		for (j = i+1; j < rap->rxa_wnd; j++) {
615 			if (rap->rxa_m[j] != NULL) {
616 				rap->rxa_m[j-i] = rap->rxa_m[j];
617 				rap->rxa_m[j] = NULL;
618 				if (--n == 0)
619 					break;
620 			}
621 		}
622 		KASSERT(n == 0, ("lost %d frames", n));
623 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
624 	}
625 	/*
626 	 * Adjust the start of the BA window to
627 	 * reflect the frames just dispatched.
628 	 */
629 	rap->rxa_start = IEEE80211_SEQ_ADD(rap->rxa_start, i);
630 	vap->iv_stats.is_ampdu_rx_oor += i;
631 }
632 
633 #ifdef IEEE80211_AMPDU_AGE
634 /*
635  * Dispatch all frames in the A-MPDU re-order queue.
636  */
637 static void
638 ampdu_rx_flush(struct ieee80211_node *ni, struct ieee80211_rx_ampdu *rap)
639 {
640 	struct ieee80211vap *vap = ni->ni_vap;
641 	struct mbuf *m;
642 	int i;
643 
644 	for (i = 0; i < rap->rxa_wnd; i++) {
645 		m = rap->rxa_m[i];
646 		if (m == NULL)
647 			continue;
648 		rap->rxa_m[i] = NULL;
649 		rap->rxa_qbytes -= m->m_pkthdr.len;
650 		rap->rxa_qframes--;
651 		vap->iv_stats.is_ampdu_rx_oor++;
652 
653 		ampdu_dispatch(ni, m);
654 		if (rap->rxa_qframes == 0)
655 			break;
656 	}
657 }
658 #endif /* IEEE80211_AMPDU_AGE */
659 
660 /*
661  * Dispatch all frames in the A-MPDU re-order queue
662  * preceding the specified sequence number.  This logic
663  * handles window moves due to a received MSDU or BAR.
664  */
665 static void
666 ampdu_rx_flush_upto(struct ieee80211_node *ni,
667 	struct ieee80211_rx_ampdu *rap, ieee80211_seq winstart)
668 {
669 	struct ieee80211vap *vap = ni->ni_vap;
670 	struct mbuf *m;
671 	ieee80211_seq seqno;
672 	int i;
673 
674 	/*
675 	 * Flush any complete MSDU's with a sequence number lower
676 	 * than winstart.  Gaps may exist.  Note that we may actually
677 	 * dispatch frames past winstart if a run continues; this is
678 	 * an optimization that avoids having to do a separate pass
679 	 * to dispatch frames after moving the BA window start.
680 	 */
681 	seqno = rap->rxa_start;
682 	for (i = 0; i < rap->rxa_wnd; i++) {
683 		m = rap->rxa_m[i];
684 		if (m != NULL) {
685 			rap->rxa_m[i] = NULL;
686 			rap->rxa_qbytes -= m->m_pkthdr.len;
687 			rap->rxa_qframes--;
688 			vap->iv_stats.is_ampdu_rx_oor++;
689 
690 			ampdu_dispatch(ni, m);
691 		} else {
692 			if (!IEEE80211_SEQ_BA_BEFORE(seqno, winstart))
693 				break;
694 		}
695 		seqno = IEEE80211_SEQ_INC(seqno);
696 	}
697 	/*
698 	 * If frames remain, copy the mbuf pointers down so
699 	 * they correspond to the offsets in the new window.
700 	 */
701 	if (rap->rxa_qframes != 0) {
702 		int n = rap->rxa_qframes, j;
703 
704 		/* NB: this loop assumes i > 0 and/or rxa_m[0] is NULL */
705 		KASSERT(rap->rxa_m[0] == NULL,
706 		    ("%s: BA window slot 0 occupied", __func__));
707 		for (j = i+1; j < rap->rxa_wnd; j++) {
708 			if (rap->rxa_m[j] != NULL) {
709 				rap->rxa_m[j-i] = rap->rxa_m[j];
710 				rap->rxa_m[j] = NULL;
711 				if (--n == 0)
712 					break;
713 			}
714 		}
715 		KASSERT(n == 0, ("%s: lost %d frames, qframes %d off %d "
716 		    "BA win <%d:%d> winstart %d",
717 		    __func__, n, rap->rxa_qframes, i, rap->rxa_start,
718 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
719 		    winstart));
720 		vap->iv_stats.is_ampdu_rx_copy += rap->rxa_qframes;
721 	}
722 	/*
723 	 * Move the start of the BA window; we use the
724 	 * sequence number of the last MSDU that was
725 	 * passed up the stack+1 or winstart if stopped on
726 	 * a gap in the reorder buffer.
727 	 */
728 	rap->rxa_start = seqno;
729 }
730 
731 /*
732  * Process a received QoS data frame for an HT station.  Handle
733  * A-MPDU reordering: if this frame is received out of order
734  * and falls within the BA window hold onto it.  Otherwise if
735  * this frame completes a run, flush any pending frames.  We
736  * return 1 if the frame is consumed.  A 0 is returned if
737  * the frame should be processed normally by the caller.
738  */
739 int
740 ieee80211_ampdu_reorder(struct ieee80211_node *ni, struct mbuf *m)
741 {
742 #define	IEEE80211_FC0_QOSDATA \
743 	(IEEE80211_FC0_TYPE_DATA|IEEE80211_FC0_SUBTYPE_QOS|IEEE80211_FC0_VERSION_0)
744 #define	PROCESS		0	/* caller should process frame */
745 #define	CONSUMED	1	/* frame consumed, caller does nothing */
746 	struct ieee80211vap *vap = ni->ni_vap;
747 	struct ieee80211_qosframe *wh;
748 	struct ieee80211_rx_ampdu *rap;
749 	ieee80211_seq rxseq;
750 	uint8_t tid;
751 	int off;
752 
753 	KASSERT((m->m_flags & (M_AMPDU | M_AMPDU_MPDU)) == M_AMPDU,
754 	    ("!a-mpdu or already re-ordered, flags 0x%x", m->m_flags));
755 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
756 
757 	/* NB: m_len known to be sufficient */
758 	wh = mtod(m, struct ieee80211_qosframe *);
759 	if (wh->i_fc[0] != IEEE80211_FC0_QOSDATA) {
760 		/*
761 		 * Not QoS data, shouldn't get here but just
762 		 * return it to the caller for processing.
763 		 */
764 		return PROCESS;
765 	}
766 	if (IEEE80211_IS_DSTODS(wh))
767 		tid = ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0];
768 	else
769 		tid = wh->i_qos[0];
770 	tid &= IEEE80211_QOS_TID;
771 	rap = &ni->ni_rx_ampdu[tid];
772 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
773 		/*
774 		 * No ADDBA request yet, don't touch.
775 		 */
776 		return PROCESS;
777 	}
778 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
779 	if ((rxseq & IEEE80211_SEQ_FRAG_MASK) != 0) {
780 		/*
781 		 * Fragments are not allowed; toss.
782 		 */
783 		IEEE80211_DISCARD_MAC(vap,
784 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
785 		    "A-MPDU", "fragment, rxseq 0x%x tid %u%s", rxseq, tid,
786 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
787 		vap->iv_stats.is_ampdu_rx_drop++;
788 		IEEE80211_NODE_STAT(ni, rx_drop);
789 		m_freem(m);
790 		return CONSUMED;
791 	}
792 	rxseq >>= IEEE80211_SEQ_SEQ_SHIFT;
793 	rap->rxa_nframes++;
794 again:
795 	if (rxseq == rap->rxa_start) {
796 		/*
797 		 * First frame in window.
798 		 */
799 		if (rap->rxa_qframes != 0) {
800 			/*
801 			 * Dispatch as many packets as we can.
802 			 */
803 			KASSERT(rap->rxa_m[0] == NULL, ("unexpected dup"));
804 			ampdu_dispatch(ni, m);
805 			ampdu_rx_dispatch(rap, ni);
806 			return CONSUMED;
807 		} else {
808 			/*
809 			 * In order; advance window and notify
810 			 * caller to dispatch directly.
811 			 */
812 			rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
813 			return PROCESS;
814 		}
815 	}
816 	/*
817 	 * Frame is out of order; store if in the BA window.
818 	 */
819 	/* calculate offset in BA window */
820 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
821 	if (off < rap->rxa_wnd) {
822 		/*
823 		 * Common case (hopefully): in the BA window.
824 		 * Sec 9.10.7.6.2 a) (p.137)
825 		 */
826 #ifdef IEEE80211_AMPDU_AGE
827 		/*
828 		 * Check for frames sitting too long in the reorder queue.
829 		 * This should only ever happen if frames are not delivered
830 		 * without the sender otherwise notifying us (e.g. with a
831 		 * BAR to move the window).  Typically this happens because
832 		 * of vendor bugs that cause the sequence number to jump.
833 		 * When this happens we get a gap in the reorder queue that
834 		 * leaves frame sitting on the queue until they get pushed
835 		 * out due to window moves.  When the vendor does not send
836 		 * BAR this move only happens due to explicit packet sends
837 		 *
838 		 * NB: we only track the time of the oldest frame in the
839 		 * reorder q; this means that if we flush we might push
840 		 * frames that still "new"; if this happens then subsequent
841 		 * frames will result in BA window moves which cost something
842 		 * but is still better than a big throughput dip.
843 		 */
844 		if (rap->rxa_qframes != 0) {
845 			/* XXX honor batimeout? */
846 			if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
847 				/*
848 				 * Too long since we received the first
849 				 * frame; flush the reorder buffer.
850 				 */
851 				if (rap->rxa_qframes != 0) {
852 					vap->iv_stats.is_ampdu_rx_age +=
853 					    rap->rxa_qframes;
854 					ampdu_rx_flush(ni, rap);
855 				}
856 				rap->rxa_start = IEEE80211_SEQ_INC(rxseq);
857 				return PROCESS;
858 			}
859 		} else {
860 			/*
861 			 * First frame, start aging timer.
862 			 */
863 			rap->rxa_age = ticks;
864 		}
865 #endif /* IEEE80211_AMPDU_AGE */
866 		/* save packet */
867 		if (rap->rxa_m[off] == NULL) {
868 			rap->rxa_m[off] = m;
869 			rap->rxa_qframes++;
870 			rap->rxa_qbytes += m->m_pkthdr.len;
871 			vap->iv_stats.is_ampdu_rx_reorder++;
872 		} else {
873 			IEEE80211_DISCARD_MAC(vap,
874 			    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
875 			    ni->ni_macaddr, "a-mpdu duplicate",
876 			    "seqno %u tid %u BA win <%u:%u>",
877 			    rxseq, tid, rap->rxa_start,
878 			    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1));
879 			vap->iv_stats.is_rx_dup++;
880 			IEEE80211_NODE_STAT(ni, rx_dup);
881 			m_freem(m);
882 		}
883 		return CONSUMED;
884 	}
885 	if (off < IEEE80211_SEQ_BA_RANGE) {
886 		/*
887 		 * Outside the BA window, but within range;
888 		 * flush the reorder q and move the window.
889 		 * Sec 9.10.7.6.2 b) (p.138)
890 		 */
891 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
892 		    "move BA win <%u:%u> (%u frames) rxseq %u tid %u",
893 		    rap->rxa_start,
894 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
895 		    rap->rxa_qframes, rxseq, tid);
896 		vap->iv_stats.is_ampdu_rx_move++;
897 
898 		/*
899 		 * The spec says to flush frames up to but not including:
900 		 * 	WinStart_B = rxseq - rap->rxa_wnd + 1
901 		 * Then insert the frame or notify the caller to process
902 		 * it immediately.  We can safely do this by just starting
903 		 * over again because we know the frame will now be within
904 		 * the BA window.
905 		 */
906 		/* NB: rxa_wnd known to be >0 */
907 		ampdu_rx_flush_upto(ni, rap,
908 		    IEEE80211_SEQ_SUB(rxseq, rap->rxa_wnd-1));
909 		goto again;
910 	} else {
911 		/*
912 		 * Outside the BA window and out of range; toss.
913 		 * Sec 9.10.7.6.2 c) (p.138)
914 		 */
915 		IEEE80211_DISCARD_MAC(vap,
916 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
917 		    "MPDU", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
918 		    rap->rxa_start,
919 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
920 		    rap->rxa_qframes, rxseq, tid,
921 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
922 		vap->iv_stats.is_ampdu_rx_drop++;
923 		IEEE80211_NODE_STAT(ni, rx_drop);
924 		m_freem(m);
925 		return CONSUMED;
926 	}
927 #undef CONSUMED
928 #undef PROCESS
929 #undef IEEE80211_FC0_QOSDATA
930 }
931 
932 /*
933  * Process a BAR ctl frame.  Dispatch all frames up to
934  * the sequence number of the frame.  If this frame is
935  * out of range it's discarded.
936  */
937 void
938 ieee80211_recv_bar(struct ieee80211_node *ni, struct mbuf *m0)
939 {
940 	struct ieee80211vap *vap = ni->ni_vap;
941 	struct ieee80211_frame_bar *wh;
942 	struct ieee80211_rx_ampdu *rap;
943 	ieee80211_seq rxseq;
944 	int tid, off;
945 
946 	if (!ieee80211_recv_bar_ena) {
947 #if 0
948 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_11N,
949 		    ni->ni_macaddr, "BAR", "%s", "processing disabled");
950 #endif
951 		vap->iv_stats.is_ampdu_bar_bad++;
952 		return;
953 	}
954 	wh = mtod(m0, struct ieee80211_frame_bar *);
955 	/* XXX check basic BAR */
956 	tid = MS(le16toh(wh->i_ctl), IEEE80211_BAR_TID);
957 	rap = &ni->ni_rx_ampdu[tid];
958 	if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
959 		/*
960 		 * No ADDBA request yet, don't touch.
961 		 */
962 		IEEE80211_DISCARD_MAC(vap,
963 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N,
964 		    ni->ni_macaddr, "BAR", "no BA stream, tid %u", tid);
965 		vap->iv_stats.is_ampdu_bar_bad++;
966 		return;
967 	}
968 	vap->iv_stats.is_ampdu_bar_rx++;
969 	rxseq = le16toh(wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT;
970 	if (rxseq == rap->rxa_start)
971 		return;
972 	/* calculate offset in BA window */
973 	off = IEEE80211_SEQ_SUB(rxseq, rap->rxa_start);
974 	if (off < IEEE80211_SEQ_BA_RANGE) {
975 		/*
976 		 * Flush the reorder q up to rxseq and move the window.
977 		 * Sec 9.10.7.6.3 a) (p.138)
978 		 */
979 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
980 		    "BAR moves BA win <%u:%u> (%u frames) rxseq %u tid %u",
981 		    rap->rxa_start,
982 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
983 		    rap->rxa_qframes, rxseq, tid);
984 		vap->iv_stats.is_ampdu_bar_move++;
985 
986 		ampdu_rx_flush_upto(ni, rap, rxseq);
987 		if (off >= rap->rxa_wnd) {
988 			/*
989 			 * BAR specifies a window start to the right of BA
990 			 * window; we must move it explicitly since
991 			 * ampdu_rx_flush_upto will not.
992 			 */
993 			rap->rxa_start = rxseq;
994 		}
995 	} else {
996 		/*
997 		 * Out of range; toss.
998 		 * Sec 9.10.7.6.3 b) (p.138)
999 		 */
1000 		IEEE80211_DISCARD_MAC(vap,
1001 		    IEEE80211_MSG_INPUT | IEEE80211_MSG_11N, ni->ni_macaddr,
1002 		    "BAR", "BA win <%u:%u> (%u frames) rxseq %u tid %u%s",
1003 		    rap->rxa_start,
1004 		    IEEE80211_SEQ_ADD(rap->rxa_start, rap->rxa_wnd-1),
1005 		    rap->rxa_qframes, rxseq, tid,
1006 		    wh->i_fc[1] & IEEE80211_FC1_RETRY ? " (retransmit)" : "");
1007 		vap->iv_stats.is_ampdu_bar_oow++;
1008 		IEEE80211_NODE_STAT(ni, rx_drop);
1009 	}
1010 }
1011 
1012 /*
1013  * Setup HT-specific state in a node.  Called only
1014  * when HT use is negotiated so we don't do extra
1015  * work for temporary and/or legacy sta's.
1016  */
1017 void
1018 ieee80211_ht_node_init(struct ieee80211_node *ni)
1019 {
1020 	struct ieee80211_tx_ampdu *tap;
1021 	int ac;
1022 
1023 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1024 		/*
1025 		 * Clean AMPDU state on re-associate.  This handles the case
1026 		 * where a station leaves w/o notifying us and then returns
1027 		 * before node is reaped for inactivity.
1028 		 */
1029 		ieee80211_ht_node_cleanup(ni);
1030 	}
1031 	for (ac = 0; ac < WME_NUM_AC; ac++) {
1032 		tap = &ni->ni_tx_ampdu[ac];
1033 		tap->txa_ac = ac;
1034 		tap->txa_ni = ni;
1035 		/* NB: further initialization deferred */
1036 	}
1037 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1038 }
1039 
1040 /*
1041  * Cleanup HT-specific state in a node.  Called only
1042  * when HT use has been marked.
1043  */
1044 void
1045 ieee80211_ht_node_cleanup(struct ieee80211_node *ni)
1046 {
1047 	struct ieee80211com *ic = ni->ni_ic;
1048 	int i;
1049 
1050 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT node"));
1051 
1052 	/* XXX optimize this */
1053 	for (i = 0; i < WME_NUM_AC; i++) {
1054 		struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[i];
1055 		if (tap->txa_flags & IEEE80211_AGGR_SETUP)
1056 			ampdu_tx_stop(tap);
1057 	}
1058 	for (i = 0; i < WME_NUM_TID; i++)
1059 		ic->ic_ampdu_rx_stop(ni, &ni->ni_rx_ampdu[i]);
1060 
1061 	ni->ni_htcap = 0;
1062 	ni->ni_flags &= ~IEEE80211_NODE_HT_ALL;
1063 }
1064 
1065 /*
1066  * Age out HT resources for a station.
1067  */
1068 void
1069 ieee80211_ht_node_age(struct ieee80211_node *ni)
1070 {
1071 #ifdef IEEE80211_AMPDU_AGE
1072 	struct ieee80211vap *vap = ni->ni_vap;
1073 	uint8_t tid;
1074 #endif
1075 
1076 	KASSERT(ni->ni_flags & IEEE80211_NODE_HT, ("not an HT sta"));
1077 
1078 #ifdef IEEE80211_AMPDU_AGE
1079 	for (tid = 0; tid < WME_NUM_TID; tid++) {
1080 		struct ieee80211_rx_ampdu *rap;
1081 
1082 		rap = &ni->ni_rx_ampdu[tid];
1083 		if ((rap->rxa_flags & IEEE80211_AGGR_XCHGPEND) == 0)
1084 			continue;
1085 		if (rap->rxa_qframes == 0)
1086 			continue;
1087 		/*
1088 		 * Check for frames sitting too long in the reorder queue.
1089 		 * See above for more details on what's happening here.
1090 		 */
1091 		/* XXX honor batimeout? */
1092 		if (ticks - rap->rxa_age > ieee80211_ampdu_age) {
1093 			/*
1094 			 * Too long since we received the first
1095 			 * frame; flush the reorder buffer.
1096 			 */
1097 			vap->iv_stats.is_ampdu_rx_age += rap->rxa_qframes;
1098 			ampdu_rx_flush(ni, rap);
1099 		}
1100 	}
1101 #endif /* IEEE80211_AMPDU_AGE */
1102 }
1103 
1104 static struct ieee80211_channel *
1105 findhtchan(struct ieee80211com *ic, struct ieee80211_channel *c, int htflags)
1106 {
1107 	return ieee80211_find_channel(ic, c->ic_freq,
1108 	    (c->ic_flags &~ IEEE80211_CHAN_HT) | htflags);
1109 }
1110 
1111 /*
1112  * Adjust a channel to be HT/non-HT according to the vap's configuration.
1113  */
1114 struct ieee80211_channel *
1115 ieee80211_ht_adjust_channel(struct ieee80211com *ic,
1116 	struct ieee80211_channel *chan, int flags)
1117 {
1118 	struct ieee80211_channel *c;
1119 
1120 	if (flags & IEEE80211_FHT_HT) {
1121 		/* promote to HT if possible */
1122 		if (flags & IEEE80211_FHT_USEHT40) {
1123 			if (!IEEE80211_IS_CHAN_HT40(chan)) {
1124 				/* NB: arbitrarily pick ht40+ over ht40- */
1125 				c = findhtchan(ic, chan, IEEE80211_CHAN_HT40U);
1126 				if (c == NULL)
1127 					c = findhtchan(ic, chan,
1128 						IEEE80211_CHAN_HT40D);
1129 				if (c == NULL)
1130 					c = findhtchan(ic, chan,
1131 						IEEE80211_CHAN_HT20);
1132 				if (c != NULL)
1133 					chan = c;
1134 			}
1135 		} else if (!IEEE80211_IS_CHAN_HT20(chan)) {
1136 			c = findhtchan(ic, chan, IEEE80211_CHAN_HT20);
1137 			if (c != NULL)
1138 				chan = c;
1139 		}
1140 	} else if (IEEE80211_IS_CHAN_HT(chan)) {
1141 		/* demote to legacy, HT use is disabled */
1142 		c = ieee80211_find_channel(ic, chan->ic_freq,
1143 		    chan->ic_flags &~ IEEE80211_CHAN_HT);
1144 		if (c != NULL)
1145 			chan = c;
1146 	}
1147 	return chan;
1148 }
1149 
1150 /*
1151  * Setup HT-specific state for a legacy WDS peer.
1152  */
1153 void
1154 ieee80211_ht_wds_init(struct ieee80211_node *ni)
1155 {
1156 	struct ieee80211vap *vap = ni->ni_vap;
1157 	struct ieee80211_tx_ampdu *tap;
1158 	int ac;
1159 
1160 	KASSERT(vap->iv_flags_ht & IEEE80211_FHT_HT, ("no HT requested"));
1161 
1162 	/* XXX check scan cache in case peer has an ap and we have info */
1163 	/*
1164 	 * If setup with a legacy channel; locate an HT channel.
1165 	 * Otherwise if the inherited channel (from a companion
1166 	 * AP) is suitable use it so we use the same location
1167 	 * for the extension channel).
1168 	 */
1169 	ni->ni_chan = ieee80211_ht_adjust_channel(ni->ni_ic,
1170 	    ni->ni_chan, ieee80211_htchanflags(ni->ni_chan));
1171 
1172 	ni->ni_htcap = 0;
1173 	if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20)
1174 		ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI20;
1175 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan)) {
1176 		ni->ni_htcap |= IEEE80211_HTCAP_CHWIDTH40;
1177 		ni->ni_chw = 40;
1178 		if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
1179 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_ABOVE;
1180 		else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
1181 			ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_BELOW;
1182 		if (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40)
1183 			ni->ni_htcap |= IEEE80211_HTCAP_SHORTGI40;
1184 	} else {
1185 		ni->ni_chw = 20;
1186 		ni->ni_ht2ndchan = IEEE80211_HTINFO_2NDCHAN_NONE;
1187 	}
1188 	ni->ni_htctlchan = ni->ni_chan->ic_ieee;
1189 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
1190 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1191 	/* XXX does it make sense to enable SMPS? */
1192 
1193 	ni->ni_htopmode = 0;		/* XXX need protection state */
1194 	ni->ni_htstbc = 0;		/* XXX need info */
1195 
1196 	for (ac = 0; ac < WME_NUM_AC; ac++) {
1197 		tap = &ni->ni_tx_ampdu[ac];
1198 		tap->txa_ac = ac;
1199 	}
1200 	/* NB: AMPDU tx/rx governed by IEEE80211_FHT_AMPDU_{TX,RX} */
1201 	ni->ni_flags |= IEEE80211_NODE_HT | IEEE80211_NODE_AMPDU;
1202 }
1203 
1204 /*
1205  * Notify hostap vaps of a change in the HTINFO ie.
1206  */
1207 static void
1208 htinfo_notify(struct ieee80211com *ic)
1209 {
1210 	struct ieee80211vap *vap;
1211 	int first = 1;
1212 
1213 	IEEE80211_LOCK_ASSERT(ic);
1214 
1215 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
1216 		if (vap->iv_opmode != IEEE80211_M_HOSTAP)
1217 			continue;
1218 		if (vap->iv_state != IEEE80211_S_RUN ||
1219 		    !IEEE80211_IS_CHAN_HT(vap->iv_bss->ni_chan))
1220 			continue;
1221 		if (first) {
1222 			IEEE80211_NOTE(vap,
1223 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N,
1224 			    vap->iv_bss,
1225 			    "HT bss occupancy change: %d sta, %d ht, "
1226 			    "%d ht40%s, HT protmode now 0x%x"
1227 			    , ic->ic_sta_assoc
1228 			    , ic->ic_ht_sta_assoc
1229 			    , ic->ic_ht40_sta_assoc
1230 			    , (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) ?
1231 				 ", non-HT sta present" : ""
1232 			    , ic->ic_curhtprotmode);
1233 			first = 0;
1234 		}
1235 		ieee80211_beacon_notify(vap, IEEE80211_BEACON_HTINFO);
1236 	}
1237 }
1238 
1239 /*
1240  * Calculate HT protection mode from current
1241  * state and handle updates.
1242  */
1243 static void
1244 htinfo_update(struct ieee80211com *ic)
1245 {
1246 	uint8_t protmode;
1247 
1248 	if (ic->ic_sta_assoc != ic->ic_ht_sta_assoc) {
1249 		protmode = IEEE80211_HTINFO_OPMODE_MIXED
1250 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1251 	} else if (ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) {
1252 		protmode = IEEE80211_HTINFO_OPMODE_PROTOPT
1253 			 | IEEE80211_HTINFO_NONHT_PRESENT;
1254 	} else if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
1255 	    IEEE80211_IS_CHAN_HT40(ic->ic_bsschan) &&
1256 	    ic->ic_sta_assoc != ic->ic_ht40_sta_assoc) {
1257 		protmode = IEEE80211_HTINFO_OPMODE_HT20PR;
1258 	} else {
1259 		protmode = IEEE80211_HTINFO_OPMODE_PURE;
1260 	}
1261 	if (protmode != ic->ic_curhtprotmode) {
1262 		ic->ic_curhtprotmode = protmode;
1263 		htinfo_notify(ic);
1264 	}
1265 }
1266 
1267 /*
1268  * Handle an HT station joining a BSS.
1269  */
1270 void
1271 ieee80211_ht_node_join(struct ieee80211_node *ni)
1272 {
1273 	struct ieee80211com *ic = ni->ni_ic;
1274 
1275 	IEEE80211_LOCK_ASSERT(ic);
1276 
1277 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1278 		ic->ic_ht_sta_assoc++;
1279 		if (ni->ni_chw == 40)
1280 			ic->ic_ht40_sta_assoc++;
1281 	}
1282 	htinfo_update(ic);
1283 }
1284 
1285 /*
1286  * Handle an HT station leaving a BSS.
1287  */
1288 void
1289 ieee80211_ht_node_leave(struct ieee80211_node *ni)
1290 {
1291 	struct ieee80211com *ic = ni->ni_ic;
1292 
1293 	IEEE80211_LOCK_ASSERT(ic);
1294 
1295 	if (ni->ni_flags & IEEE80211_NODE_HT) {
1296 		ic->ic_ht_sta_assoc--;
1297 		if (ni->ni_chw == 40)
1298 			ic->ic_ht40_sta_assoc--;
1299 	}
1300 	htinfo_update(ic);
1301 }
1302 
1303 /*
1304  * Public version of htinfo_update; used for processing
1305  * beacon frames from overlapping bss.
1306  *
1307  * Caller can specify either IEEE80211_HTINFO_OPMODE_MIXED
1308  * (on receipt of a beacon that advertises MIXED) or
1309  * IEEE80211_HTINFO_OPMODE_PROTOPT (on receipt of a beacon
1310  * from an overlapping legacy bss).  We treat MIXED with
1311  * a higher precedence than PROTOPT (i.e. we will not change
1312  * change PROTOPT -> MIXED; only MIXED -> PROTOPT).  This
1313  * corresponds to how we handle things in htinfo_update.
1314  */
1315 void
1316 ieee80211_htprot_update(struct ieee80211com *ic, int protmode)
1317 {
1318 #define	OPMODE(x)	SM(x, IEEE80211_HTINFO_OPMODE)
1319 	IEEE80211_LOCK(ic);
1320 
1321 	/* track non-HT station presence */
1322 	KASSERT(protmode & IEEE80211_HTINFO_NONHT_PRESENT,
1323 	    ("protmode 0x%x", protmode));
1324 	ic->ic_flags_ht |= IEEE80211_FHT_NONHT_PR;
1325 	ic->ic_lastnonht = ticks;
1326 
1327 	if (protmode != ic->ic_curhtprotmode &&
1328 	    (OPMODE(ic->ic_curhtprotmode) != IEEE80211_HTINFO_OPMODE_MIXED ||
1329 	     OPMODE(protmode) == IEEE80211_HTINFO_OPMODE_PROTOPT)) {
1330 		/* push beacon update */
1331 		ic->ic_curhtprotmode = protmode;
1332 		htinfo_notify(ic);
1333 	}
1334 	IEEE80211_UNLOCK(ic);
1335 #undef OPMODE
1336 }
1337 
1338 /*
1339  * Time out presence of an overlapping bss with non-HT
1340  * stations.  When operating in hostap mode we listen for
1341  * beacons from other stations and if we identify a non-HT
1342  * station is present we update the opmode field of the
1343  * HTINFO ie.  To identify when all non-HT stations are
1344  * gone we time out this condition.
1345  */
1346 void
1347 ieee80211_ht_timeout(struct ieee80211com *ic)
1348 {
1349 	IEEE80211_LOCK_ASSERT(ic);
1350 
1351 	if ((ic->ic_flags_ht & IEEE80211_FHT_NONHT_PR) &&
1352 	    time_after(ticks, ic->ic_lastnonht + IEEE80211_NONHT_PRESENT_AGE)) {
1353 #if 0
1354 		IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
1355 		    "%s", "time out non-HT STA present on channel");
1356 #endif
1357 		ic->ic_flags_ht &= ~IEEE80211_FHT_NONHT_PR;
1358 		htinfo_update(ic);
1359 	}
1360 }
1361 
1362 /* unalligned little endian access */
1363 #define LE_READ_2(p)					\
1364 	((uint16_t)					\
1365 	 ((((const uint8_t *)(p))[0]      ) |		\
1366 	  (((const uint8_t *)(p))[1] <<  8)))
1367 
1368 /*
1369  * Process an 802.11n HT capabilities ie.
1370  */
1371 void
1372 ieee80211_parse_htcap(struct ieee80211_node *ni, const uint8_t *ie)
1373 {
1374 	if (ie[0] == IEEE80211_ELEMID_VENDOR) {
1375 		/*
1376 		 * Station used Vendor OUI ie to associate;
1377 		 * mark the node so when we respond we'll use
1378 		 * the Vendor OUI's and not the standard ie's.
1379 		 */
1380 		ni->ni_flags |= IEEE80211_NODE_HTCOMPAT;
1381 		ie += 4;
1382 	} else
1383 		ni->ni_flags &= ~IEEE80211_NODE_HTCOMPAT;
1384 
1385 	ni->ni_htcap = LE_READ_2(ie +
1386 		__offsetof(struct ieee80211_ie_htcap, hc_cap));
1387 	ni->ni_htparam = ie[__offsetof(struct ieee80211_ie_htcap, hc_param)];
1388 }
1389 
1390 static void
1391 htinfo_parse(struct ieee80211_node *ni,
1392 	const struct ieee80211_ie_htinfo *htinfo)
1393 {
1394 	uint16_t w;
1395 
1396 	ni->ni_htctlchan = htinfo->hi_ctrlchannel;
1397 	ni->ni_ht2ndchan = SM(htinfo->hi_byte1, IEEE80211_HTINFO_2NDCHAN);
1398 	w = LE_READ_2(&htinfo->hi_byte2);
1399 	ni->ni_htopmode = SM(w, IEEE80211_HTINFO_OPMODE);
1400 	w = LE_READ_2(&htinfo->hi_byte45);
1401 	ni->ni_htstbc = SM(w, IEEE80211_HTINFO_BASIC_STBCMCS);
1402 }
1403 
1404 /*
1405  * Parse an 802.11n HT info ie and save useful information
1406  * to the node state.  Note this does not effect any state
1407  * changes such as for channel width change.
1408  */
1409 void
1410 ieee80211_parse_htinfo(struct ieee80211_node *ni, const uint8_t *ie)
1411 {
1412 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1413 		ie += 4;
1414 	htinfo_parse(ni, (const struct ieee80211_ie_htinfo *) ie);
1415 }
1416 
1417 /*
1418  * Handle 11n channel switch.  Use the received HT ie's to
1419  * identify the right channel to use.  If we cannot locate it
1420  * in the channel table then fallback to legacy operation.
1421  * Note that we use this information to identify the node's
1422  * channel only; the caller is responsible for insuring any
1423  * required channel change is done (e.g. in sta mode when
1424  * parsing the contents of a beacon frame).
1425  */
1426 static void
1427 htinfo_update_chw(struct ieee80211_node *ni, int htflags)
1428 {
1429 	struct ieee80211com *ic = ni->ni_ic;
1430 	struct ieee80211_channel *c;
1431 	int chanflags;
1432 
1433 	chanflags = (ni->ni_chan->ic_flags &~ IEEE80211_CHAN_HT) | htflags;
1434 	if (chanflags != ni->ni_chan->ic_flags) {
1435 		/* XXX not right for ht40- */
1436 		c = ieee80211_find_channel(ic, ni->ni_chan->ic_freq, chanflags);
1437 		if (c == NULL && (htflags & IEEE80211_CHAN_HT40)) {
1438 			/*
1439 			 * No HT40 channel entry in our table; fall back
1440 			 * to HT20 operation.  This should not happen.
1441 			 */
1442 			c = findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT20);
1443 #if 0
1444 			IEEE80211_NOTE(ni->ni_vap,
1445 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1446 			    "no HT40 channel (freq %u), falling back to HT20",
1447 			    ni->ni_chan->ic_freq);
1448 #endif
1449 			/* XXX stat */
1450 		}
1451 		if (c != NULL && c != ni->ni_chan) {
1452 			IEEE80211_NOTE(ni->ni_vap,
1453 			    IEEE80211_MSG_ASSOC | IEEE80211_MSG_11N, ni,
1454 			    "switch station to HT%d channel %u/0x%x",
1455 			    IEEE80211_IS_CHAN_HT40(c) ? 40 : 20,
1456 			    c->ic_freq, c->ic_flags);
1457 			ni->ni_chan = c;
1458 		}
1459 		/* NB: caller responsible for forcing any channel change */
1460 	}
1461 	/* update node's tx channel width */
1462 	ni->ni_chw = IEEE80211_IS_CHAN_HT40(ni->ni_chan)? 40 : 20;
1463 }
1464 
1465 /*
1466  * Update 11n MIMO PS state according to received htcap.
1467  */
1468 static __inline int
1469 htcap_update_mimo_ps(struct ieee80211_node *ni)
1470 {
1471 	uint16_t oflags = ni->ni_flags;
1472 
1473 	switch (ni->ni_htcap & IEEE80211_HTCAP_SMPS) {
1474 	case IEEE80211_HTCAP_SMPS_DYNAMIC:
1475 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1476 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
1477 		break;
1478 	case IEEE80211_HTCAP_SMPS_ENA:
1479 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
1480 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1481 		break;
1482 	case IEEE80211_HTCAP_SMPS_OFF:
1483 	default:		/* disable on rx of reserved value */
1484 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
1485 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
1486 		break;
1487 	}
1488 	return (oflags ^ ni->ni_flags);
1489 }
1490 
1491 /*
1492  * Update short GI state according to received htcap
1493  * and local settings.
1494  */
1495 static __inline void
1496 htcap_update_shortgi(struct ieee80211_node *ni)
1497 {
1498 	struct ieee80211vap *vap = ni->ni_vap;
1499 
1500 	ni->ni_flags &= ~(IEEE80211_NODE_SGI20|IEEE80211_NODE_SGI40);
1501 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20) &&
1502 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20))
1503 		ni->ni_flags |= IEEE80211_NODE_SGI20;
1504 	if ((ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40) &&
1505 	    (vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40))
1506 		ni->ni_flags |= IEEE80211_NODE_SGI40;
1507 }
1508 
1509 /*
1510  * Parse and update HT-related state extracted from
1511  * the HT cap and info ie's.
1512  */
1513 void
1514 ieee80211_ht_updateparams(struct ieee80211_node *ni,
1515 	const uint8_t *htcapie, const uint8_t *htinfoie)
1516 {
1517 	struct ieee80211vap *vap = ni->ni_vap;
1518 	const struct ieee80211_ie_htinfo *htinfo;
1519 	int htflags;
1520 
1521 	ieee80211_parse_htcap(ni, htcapie);
1522 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1523 		htcap_update_mimo_ps(ni);
1524 	htcap_update_shortgi(ni);
1525 
1526 	if (htinfoie[0] == IEEE80211_ELEMID_VENDOR)
1527 		htinfoie += 4;
1528 	htinfo = (const struct ieee80211_ie_htinfo *) htinfoie;
1529 	htinfo_parse(ni, htinfo);
1530 
1531 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1532 	    IEEE80211_CHAN_HT20 : 0;
1533 	/* NB: honor operating mode constraint */
1534 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_TXWIDTH_2040) &&
1535 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1536 		if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_ABOVE)
1537 			htflags = IEEE80211_CHAN_HT40U;
1538 		else if (ni->ni_ht2ndchan == IEEE80211_HTINFO_2NDCHAN_BELOW)
1539 			htflags = IEEE80211_CHAN_HT40D;
1540 	}
1541 	htinfo_update_chw(ni, htflags);
1542 
1543 	if ((htinfo->hi_byte1 & IEEE80211_HTINFO_RIFSMODE_PERM) &&
1544 	    (vap->iv_flags_ht & IEEE80211_FHT_RIFS))
1545 		ni->ni_flags |= IEEE80211_NODE_RIFS;
1546 	else
1547 		ni->ni_flags &= ~IEEE80211_NODE_RIFS;
1548 }
1549 
1550 /*
1551  * Parse and update HT-related state extracted from the HT cap ie
1552  * for a station joining an HT BSS.
1553  */
1554 void
1555 ieee80211_ht_updatehtcap(struct ieee80211_node *ni, const uint8_t *htcapie)
1556 {
1557 	struct ieee80211vap *vap = ni->ni_vap;
1558 	int htflags;
1559 
1560 	ieee80211_parse_htcap(ni, htcapie);
1561 	if (vap->iv_htcaps & IEEE80211_HTCAP_SMPS)
1562 		htcap_update_mimo_ps(ni);
1563 	htcap_update_shortgi(ni);
1564 
1565 	/* NB: honor operating mode constraint */
1566 	/* XXX 40 MHz intolerant */
1567 	htflags = (vap->iv_flags_ht & IEEE80211_FHT_HT) ?
1568 	    IEEE80211_CHAN_HT20 : 0;
1569 	if ((ni->ni_htcap & IEEE80211_HTCAP_CHWIDTH40) &&
1570 	    (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)) {
1571 		if (IEEE80211_IS_CHAN_HT40U(vap->iv_bss->ni_chan))
1572 			htflags = IEEE80211_CHAN_HT40U;
1573 		else if (IEEE80211_IS_CHAN_HT40D(vap->iv_bss->ni_chan))
1574 			htflags = IEEE80211_CHAN_HT40D;
1575 	}
1576 	htinfo_update_chw(ni, htflags);
1577 }
1578 
1579 /*
1580  * Install received HT rate set by parsing the HT cap ie.
1581  */
1582 int
1583 ieee80211_setup_htrates(struct ieee80211_node *ni, const uint8_t *ie, int flags)
1584 {
1585 	struct ieee80211com *ic = ni->ni_ic;
1586 	struct ieee80211vap *vap = ni->ni_vap;
1587 	const struct ieee80211_ie_htcap *htcap;
1588 	struct ieee80211_htrateset *rs;
1589 	int i, maxequalmcs, maxunequalmcs;
1590 
1591 	maxequalmcs = ic->ic_txstream * 8 - 1;
1592 	if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL) {
1593 		if (ic->ic_txstream >= 2)
1594 			maxunequalmcs = 38;
1595 		if (ic->ic_txstream >= 3)
1596 			maxunequalmcs = 52;
1597 		if (ic->ic_txstream >= 4)
1598 			maxunequalmcs = 76;
1599 	} else
1600 		maxunequalmcs = 0;
1601 
1602 	rs = &ni->ni_htrates;
1603 	memset(rs, 0, sizeof(*rs));
1604 	if (ie != NULL) {
1605 		if (ie[0] == IEEE80211_ELEMID_VENDOR)
1606 			ie += 4;
1607 		htcap = (const struct ieee80211_ie_htcap *) ie;
1608 		for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1609 			if (isclr(htcap->hc_mcsset, i))
1610 				continue;
1611 			if (rs->rs_nrates == IEEE80211_HTRATE_MAXSIZE) {
1612 				IEEE80211_NOTE(vap,
1613 				    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1614 				    "WARNING, HT rate set too large; only "
1615 				    "using %u rates", IEEE80211_HTRATE_MAXSIZE);
1616 				vap->iv_stats.is_rx_rstoobig++;
1617 				break;
1618 			}
1619 			if (i <= 31 && i > maxequalmcs)
1620 				continue;
1621 			if (i == 32 &&
1622 			    (ic->ic_htcaps & IEEE80211_HTC_TXMCS32) == 0)
1623 				continue;
1624 			if (i > 32 && i > maxunequalmcs)
1625 				continue;
1626 			rs->rs_rates[rs->rs_nrates++] = i;
1627 		}
1628 	}
1629 	return ieee80211_fix_rate(ni, (struct ieee80211_rateset *) rs, flags);
1630 }
1631 
1632 /*
1633  * Mark rates in a node's HT rate set as basic according
1634  * to the information in the supplied HT info ie.
1635  */
1636 void
1637 ieee80211_setup_basic_htrates(struct ieee80211_node *ni, const uint8_t *ie)
1638 {
1639 	const struct ieee80211_ie_htinfo *htinfo;
1640 	struct ieee80211_htrateset *rs;
1641 	int i, j;
1642 
1643 	if (ie[0] == IEEE80211_ELEMID_VENDOR)
1644 		ie += 4;
1645 	htinfo = (const struct ieee80211_ie_htinfo *) ie;
1646 	rs = &ni->ni_htrates;
1647 	if (rs->rs_nrates == 0) {
1648 		IEEE80211_NOTE(ni->ni_vap,
1649 		    IEEE80211_MSG_XRATE | IEEE80211_MSG_11N, ni,
1650 		    "%s", "WARNING, empty HT rate set");
1651 		return;
1652 	}
1653 	for (i = 0; i < IEEE80211_HTRATE_MAXSIZE; i++) {
1654 		if (isclr(htinfo->hi_basicmcsset, i))
1655 			continue;
1656 		for (j = 0; j < rs->rs_nrates; j++)
1657 			if ((rs->rs_rates[j] & IEEE80211_RATE_VAL) == i)
1658 				rs->rs_rates[j] |= IEEE80211_RATE_BASIC;
1659 	}
1660 }
1661 
1662 static void
1663 ampdu_tx_setup(struct ieee80211_tx_ampdu *tap)
1664 {
1665 	callout_init(&tap->txa_timer, CALLOUT_MPSAFE);
1666 	tap->txa_flags |= IEEE80211_AGGR_SETUP;
1667 }
1668 
1669 static void
1670 ampdu_tx_stop(struct ieee80211_tx_ampdu *tap)
1671 {
1672 	struct ieee80211_node *ni = tap->txa_ni;
1673 	struct ieee80211com *ic = ni->ni_ic;
1674 
1675 	KASSERT(tap->txa_flags & IEEE80211_AGGR_SETUP,
1676 	    ("txa_flags 0x%x ac %d", tap->txa_flags, tap->txa_ac));
1677 
1678 	/*
1679 	 * Stop BA stream if setup so driver has a chance
1680 	 * to reclaim any resources it might have allocated.
1681 	 */
1682 	ic->ic_addba_stop(ni, tap);
1683 	/*
1684 	 * Stop any pending BAR transmit.
1685 	 */
1686 	bar_stop_timer(tap);
1687 
1688 	tap->txa_lastsample = 0;
1689 	tap->txa_avgpps = 0;
1690 	/* NB: clearing NAK means we may re-send ADDBA */
1691 	tap->txa_flags &= ~(IEEE80211_AGGR_SETUP | IEEE80211_AGGR_NAK);
1692 }
1693 
1694 static void
1695 addba_timeout(void *arg)
1696 {
1697 	struct ieee80211_tx_ampdu *tap = arg;
1698 
1699 	/* XXX ? */
1700 	tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1701 	tap->txa_attempts++;
1702 }
1703 
1704 static void
1705 addba_start_timeout(struct ieee80211_tx_ampdu *tap)
1706 {
1707 	/* XXX use CALLOUT_PENDING instead? */
1708 	callout_reset(&tap->txa_timer, ieee80211_addba_timeout,
1709 	    addba_timeout, tap);
1710 	tap->txa_flags |= IEEE80211_AGGR_XCHGPEND;
1711 	tap->txa_nextrequest = ticks + ieee80211_addba_timeout;
1712 }
1713 
1714 static void
1715 addba_stop_timeout(struct ieee80211_tx_ampdu *tap)
1716 {
1717 	/* XXX use CALLOUT_PENDING instead? */
1718 	if (tap->txa_flags & IEEE80211_AGGR_XCHGPEND) {
1719 		callout_stop(&tap->txa_timer);
1720 		tap->txa_flags &= ~IEEE80211_AGGR_XCHGPEND;
1721 	}
1722 }
1723 
1724 /*
1725  * Default method for requesting A-MPDU tx aggregation.
1726  * We setup the specified state block and start a timer
1727  * to wait for an ADDBA response frame.
1728  */
1729 static int
1730 ieee80211_addba_request(struct ieee80211_node *ni,
1731 	struct ieee80211_tx_ampdu *tap,
1732 	int dialogtoken, int baparamset, int batimeout)
1733 {
1734 	int bufsiz;
1735 
1736 	/* XXX locking */
1737 	tap->txa_token = dialogtoken;
1738 	tap->txa_flags |= IEEE80211_AGGR_IMMEDIATE;
1739 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1740 	tap->txa_wnd = (bufsiz == 0) ?
1741 	    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1742 	addba_start_timeout(tap);
1743 	return 1;
1744 }
1745 
1746 /*
1747  * Default method for processing an A-MPDU tx aggregation
1748  * response.  We shutdown any pending timer and update the
1749  * state block according to the reply.
1750  */
1751 static int
1752 ieee80211_addba_response(struct ieee80211_node *ni,
1753 	struct ieee80211_tx_ampdu *tap,
1754 	int status, int baparamset, int batimeout)
1755 {
1756 	int bufsiz, tid;
1757 
1758 	/* XXX locking */
1759 	addba_stop_timeout(tap);
1760 	if (status == IEEE80211_STATUS_SUCCESS) {
1761 		bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1762 		/* XXX override our request? */
1763 		tap->txa_wnd = (bufsiz == 0) ?
1764 		    IEEE80211_AGGR_BAWMAX : min(bufsiz, IEEE80211_AGGR_BAWMAX);
1765 		/* XXX AC/TID */
1766 		tid = MS(baparamset, IEEE80211_BAPS_TID);
1767 		tap->txa_flags |= IEEE80211_AGGR_RUNNING;
1768 		tap->txa_attempts = 0;
1769 	} else {
1770 		/* mark tid so we don't try again */
1771 		tap->txa_flags |= IEEE80211_AGGR_NAK;
1772 	}
1773 	return 1;
1774 }
1775 
1776 /*
1777  * Default method for stopping A-MPDU tx aggregation.
1778  * Any timer is cleared and we drain any pending frames.
1779  */
1780 static void
1781 ieee80211_addba_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap)
1782 {
1783 	/* XXX locking */
1784 	addba_stop_timeout(tap);
1785 	if (tap->txa_flags & IEEE80211_AGGR_RUNNING) {
1786 		/* XXX clear aggregation queue */
1787 		tap->txa_flags &= ~IEEE80211_AGGR_RUNNING;
1788 	}
1789 	tap->txa_attempts = 0;
1790 }
1791 
1792 /*
1793  * Process a received action frame using the default aggregation
1794  * policy.  We intercept ADDBA-related frames and use them to
1795  * update our aggregation state.  All other frames are passed up
1796  * for processing by ieee80211_recv_action.
1797  */
1798 static int
1799 ht_recv_action_ba_addba_request(struct ieee80211_node *ni,
1800 	const struct ieee80211_frame *wh,
1801 	const uint8_t *frm, const uint8_t *efrm)
1802 {
1803 	struct ieee80211com *ic = ni->ni_ic;
1804 	struct ieee80211vap *vap = ni->ni_vap;
1805 	struct ieee80211_rx_ampdu *rap;
1806 	uint8_t dialogtoken;
1807 	uint16_t baparamset, batimeout, baseqctl;
1808 	uint16_t args[5];
1809 	int tid;
1810 
1811 	dialogtoken = frm[2];
1812 	baparamset = LE_READ_2(frm+3);
1813 	batimeout = LE_READ_2(frm+5);
1814 	baseqctl = LE_READ_2(frm+7);
1815 
1816 	tid = MS(baparamset, IEEE80211_BAPS_TID);
1817 
1818 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1819 	    "recv ADDBA request: dialogtoken %u baparamset 0x%x "
1820 	    "(tid %d bufsiz %d) batimeout %d baseqctl %d:%d",
1821 	    dialogtoken, baparamset,
1822 	    tid, MS(baparamset, IEEE80211_BAPS_BUFSIZ),
1823 	    batimeout,
1824 	    MS(baseqctl, IEEE80211_BASEQ_START),
1825 	    MS(baseqctl, IEEE80211_BASEQ_FRAG));
1826 
1827 	rap = &ni->ni_rx_ampdu[tid];
1828 
1829 	/* Send ADDBA response */
1830 	args[0] = dialogtoken;
1831 	/*
1832 	 * NB: We ack only if the sta associated with HT and
1833 	 * the ap is configured to do AMPDU rx (the latter
1834 	 * violates the 11n spec and is mostly for testing).
1835 	 */
1836 	if ((ni->ni_flags & IEEE80211_NODE_AMPDU_RX) &&
1837 	    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_RX)) {
1838 		/* XXX handle ampdu_rx_start failure */
1839 		ic->ic_ampdu_rx_start(ni, rap,
1840 		    baparamset, batimeout, baseqctl);
1841 
1842 		args[1] = IEEE80211_STATUS_SUCCESS;
1843 	} else {
1844 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1845 		    ni, "reject ADDBA request: %s",
1846 		    ni->ni_flags & IEEE80211_NODE_AMPDU_RX ?
1847 		       "administratively disabled" :
1848 		       "not negotiated for station");
1849 		vap->iv_stats.is_addba_reject++;
1850 		args[1] = IEEE80211_STATUS_UNSPECIFIED;
1851 	}
1852 	/* XXX honor rap flags? */
1853 	args[2] = IEEE80211_BAPS_POLICY_IMMEDIATE
1854 		| SM(tid, IEEE80211_BAPS_TID)
1855 		| SM(rap->rxa_wnd, IEEE80211_BAPS_BUFSIZ)
1856 		;
1857 	args[3] = 0;
1858 	args[4] = 0;
1859 	ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
1860 		IEEE80211_ACTION_BA_ADDBA_RESPONSE, args);
1861 	return 0;
1862 }
1863 
1864 static int
1865 ht_recv_action_ba_addba_response(struct ieee80211_node *ni,
1866 	const struct ieee80211_frame *wh,
1867 	const uint8_t *frm, const uint8_t *efrm)
1868 {
1869 	struct ieee80211com *ic = ni->ni_ic;
1870 	struct ieee80211vap *vap = ni->ni_vap;
1871 	struct ieee80211_tx_ampdu *tap;
1872 	uint8_t dialogtoken, policy;
1873 	uint16_t baparamset, batimeout, code;
1874 	int tid, ac, bufsiz;
1875 
1876 	dialogtoken = frm[2];
1877 	code = LE_READ_2(frm+3);
1878 	baparamset = LE_READ_2(frm+5);
1879 	tid = MS(baparamset, IEEE80211_BAPS_TID);
1880 	bufsiz = MS(baparamset, IEEE80211_BAPS_BUFSIZ);
1881 	policy = MS(baparamset, IEEE80211_BAPS_POLICY);
1882 	batimeout = LE_READ_2(frm+7);
1883 
1884 	ac = TID_TO_WME_AC(tid);
1885 	tap = &ni->ni_tx_ampdu[ac];
1886 	if ((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0) {
1887 		IEEE80211_DISCARD_MAC(vap,
1888 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1889 		    ni->ni_macaddr, "ADDBA response",
1890 		    "no pending ADDBA, tid %d dialogtoken %u "
1891 		    "code %d", tid, dialogtoken, code);
1892 		vap->iv_stats.is_addba_norequest++;
1893 		return 0;
1894 	}
1895 	if (dialogtoken != tap->txa_token) {
1896 		IEEE80211_DISCARD_MAC(vap,
1897 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1898 		    ni->ni_macaddr, "ADDBA response",
1899 		    "dialogtoken mismatch: waiting for %d, "
1900 		    "received %d, tid %d code %d",
1901 		    tap->txa_token, dialogtoken, tid, code);
1902 		vap->iv_stats.is_addba_badtoken++;
1903 		return 0;
1904 	}
1905 	/* NB: assumes IEEE80211_AGGR_IMMEDIATE is 1 */
1906 	if (policy != (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE)) {
1907 		IEEE80211_DISCARD_MAC(vap,
1908 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1909 		    ni->ni_macaddr, "ADDBA response",
1910 		    "policy mismatch: expecting %s, "
1911 		    "received %s, tid %d code %d",
1912 		    tap->txa_flags & IEEE80211_AGGR_IMMEDIATE,
1913 		    policy, tid, code);
1914 		vap->iv_stats.is_addba_badpolicy++;
1915 		return 0;
1916 	}
1917 #if 0
1918 	/* XXX we take MIN in ieee80211_addba_response */
1919 	if (bufsiz > IEEE80211_AGGR_BAWMAX) {
1920 		IEEE80211_DISCARD_MAC(vap,
1921 		    IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
1922 		    ni->ni_macaddr, "ADDBA response",
1923 		    "BA window too large: max %d, "
1924 		    "received %d, tid %d code %d",
1925 		    bufsiz, IEEE80211_AGGR_BAWMAX, tid, code);
1926 		vap->iv_stats.is_addba_badbawinsize++;
1927 		return 0;
1928 	}
1929 #endif
1930 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1931 	    "recv ADDBA response: dialogtoken %u code %d "
1932 	    "baparamset 0x%x (tid %d bufsiz %d) batimeout %d",
1933 	    dialogtoken, code, baparamset, tid, bufsiz,
1934 	    batimeout);
1935 	ic->ic_addba_response(ni, tap, code, baparamset, batimeout);
1936 	return 0;
1937 }
1938 
1939 static int
1940 ht_recv_action_ba_delba(struct ieee80211_node *ni,
1941 	const struct ieee80211_frame *wh,
1942 	const uint8_t *frm, const uint8_t *efrm)
1943 {
1944 	struct ieee80211com *ic = ni->ni_ic;
1945 	struct ieee80211_rx_ampdu *rap;
1946 	struct ieee80211_tx_ampdu *tap;
1947 	uint16_t baparamset, code;
1948 	int tid, ac;
1949 
1950 	baparamset = LE_READ_2(frm+2);
1951 	code = LE_READ_2(frm+4);
1952 
1953 	tid = MS(baparamset, IEEE80211_DELBAPS_TID);
1954 
1955 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1956 	    "recv DELBA: baparamset 0x%x (tid %d initiator %d) "
1957 	    "code %d", baparamset, tid,
1958 	    MS(baparamset, IEEE80211_DELBAPS_INIT), code);
1959 
1960 	if ((baparamset & IEEE80211_DELBAPS_INIT) == 0) {
1961 		ac = TID_TO_WME_AC(tid);
1962 		tap = &ni->ni_tx_ampdu[ac];
1963 		ic->ic_addba_stop(ni, tap);
1964 	} else {
1965 		rap = &ni->ni_rx_ampdu[tid];
1966 		ic->ic_ampdu_rx_stop(ni, rap);
1967 	}
1968 	return 0;
1969 }
1970 
1971 static int
1972 ht_recv_action_ht_txchwidth(struct ieee80211_node *ni,
1973 	const struct ieee80211_frame *wh,
1974 	const uint8_t *frm, const uint8_t *efrm)
1975 {
1976 	int chw;
1977 
1978 	chw = (frm[2] == IEEE80211_A_HT_TXCHWIDTH_2040) ? 40 : 20;
1979 
1980 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
1981 	    "%s: HT txchwidth, width %d%s",
1982 	    __func__, chw, ni->ni_chw != chw ? "*" : "");
1983 	if (chw != ni->ni_chw) {
1984 		ni->ni_chw = chw;
1985 		/* XXX notify on change */
1986 	}
1987 	return 0;
1988 }
1989 
1990 static int
1991 ht_recv_action_ht_mimopwrsave(struct ieee80211_node *ni,
1992 	const struct ieee80211_frame *wh,
1993 	const uint8_t *frm, const uint8_t *efrm)
1994 {
1995 	const struct ieee80211_action_ht_mimopowersave *mps =
1996 	    (const struct ieee80211_action_ht_mimopowersave *) frm;
1997 
1998 	/* XXX check iv_htcaps */
1999 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_ENA)
2000 		ni->ni_flags |= IEEE80211_NODE_MIMO_PS;
2001 	else
2002 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_PS;
2003 	if (mps->am_control & IEEE80211_A_HT_MIMOPWRSAVE_MODE)
2004 		ni->ni_flags |= IEEE80211_NODE_MIMO_RTS;
2005 	else
2006 		ni->ni_flags &= ~IEEE80211_NODE_MIMO_RTS;
2007 	/* XXX notify on change */
2008 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2009 	    "%s: HT MIMO PS (%s%s)", __func__,
2010 	    (ni->ni_flags & IEEE80211_NODE_MIMO_PS) ?  "on" : "off",
2011 	    (ni->ni_flags & IEEE80211_NODE_MIMO_RTS) ?  "+rts" : ""
2012 	);
2013 	return 0;
2014 }
2015 
2016 /*
2017  * Transmit processing.
2018  */
2019 
2020 /*
2021  * Check if A-MPDU should be requested/enabled for a stream.
2022  * We require a traffic rate above a per-AC threshold and we
2023  * also handle backoff from previous failed attempts.
2024  *
2025  * Drivers may override this method to bring in information
2026  * such as link state conditions in making the decision.
2027  */
2028 static int
2029 ieee80211_ampdu_enable(struct ieee80211_node *ni,
2030 	struct ieee80211_tx_ampdu *tap)
2031 {
2032 	struct ieee80211vap *vap = ni->ni_vap;
2033 
2034 	if (tap->txa_avgpps < vap->iv_ampdu_mintraffic[tap->txa_ac])
2035 		return 0;
2036 	/* XXX check rssi? */
2037 	if (tap->txa_attempts >= ieee80211_addba_maxtries &&
2038 	    ticks < tap->txa_nextrequest) {
2039 		/*
2040 		 * Don't retry too often; txa_nextrequest is set
2041 		 * to the minimum interval we'll retry after
2042 		 * ieee80211_addba_maxtries failed attempts are made.
2043 		 */
2044 		return 0;
2045 	}
2046 	IEEE80211_NOTE(vap, IEEE80211_MSG_11N, ni,
2047 	    "enable AMPDU on %s, avgpps %d pkts %d",
2048 	    ieee80211_wme_acnames[tap->txa_ac], tap->txa_avgpps, tap->txa_pkts);
2049 	return 1;
2050 }
2051 
2052 /*
2053  * Request A-MPDU tx aggregation.  Setup local state and
2054  * issue an ADDBA request.  BA use will only happen after
2055  * the other end replies with ADDBA response.
2056  */
2057 int
2058 ieee80211_ampdu_request(struct ieee80211_node *ni,
2059 	struct ieee80211_tx_ampdu *tap)
2060 {
2061 	struct ieee80211com *ic = ni->ni_ic;
2062 	uint16_t args[5];
2063 	int tid, dialogtoken;
2064 	static int tokens = 0;	/* XXX */
2065 
2066 	/* XXX locking */
2067 	if ((tap->txa_flags & IEEE80211_AGGR_SETUP) == 0) {
2068 		/* do deferred setup of state */
2069 		ampdu_tx_setup(tap);
2070 	}
2071 	/* XXX hack for not doing proper locking */
2072 	tap->txa_flags &= ~IEEE80211_AGGR_NAK;
2073 
2074 	dialogtoken = (tokens+1) % 63;		/* XXX */
2075 	tid = WME_AC_TO_TID(tap->txa_ac);
2076 	tap->txa_start = ni->ni_txseqs[tid];
2077 
2078 	args[0] = dialogtoken;
2079 	args[1] = 0;	/* NB: status code not used */
2080 	args[2]	= IEEE80211_BAPS_POLICY_IMMEDIATE
2081 		| SM(tid, IEEE80211_BAPS_TID)
2082 		| SM(IEEE80211_AGGR_BAWMAX, IEEE80211_BAPS_BUFSIZ)
2083 		;
2084 	args[3] = 0;	/* batimeout */
2085 	/* NB: do first so there's no race against reply */
2086 	if (!ic->ic_addba_request(ni, tap, dialogtoken, args[2], args[3])) {
2087 		/* unable to setup state, don't make request */
2088 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2089 		    ni, "%s: could not setup BA stream for AC %d",
2090 		    __func__, tap->txa_ac);
2091 		/* defer next try so we don't slam the driver with requests */
2092 		tap->txa_attempts = ieee80211_addba_maxtries;
2093 		/* NB: check in case driver wants to override */
2094 		if (tap->txa_nextrequest <= ticks)
2095 			tap->txa_nextrequest = ticks + ieee80211_addba_backoff;
2096 		return 0;
2097 	}
2098 	tokens = dialogtoken;			/* allocate token */
2099 	/* NB: after calling ic_addba_request so driver can set txa_start */
2100 	args[4] = SM(tap->txa_start, IEEE80211_BASEQ_START)
2101 		| SM(0, IEEE80211_BASEQ_FRAG)
2102 		;
2103 	return ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2104 		IEEE80211_ACTION_BA_ADDBA_REQUEST, args);
2105 }
2106 
2107 /*
2108  * Terminate an AMPDU tx stream.  State is reclaimed
2109  * and the peer notified with a DelBA Action frame.
2110  */
2111 void
2112 ieee80211_ampdu_stop(struct ieee80211_node *ni, struct ieee80211_tx_ampdu *tap,
2113 	int reason)
2114 {
2115 	struct ieee80211com *ic = ni->ni_ic;
2116 	struct ieee80211vap *vap = ni->ni_vap;
2117 	uint16_t args[4];
2118 
2119 	/* XXX locking */
2120 	tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2121 	if (IEEE80211_AMPDU_RUNNING(tap)) {
2122 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2123 		    ni, "%s: stop BA stream for AC %d (reason %d)",
2124 		    __func__, tap->txa_ac, reason);
2125 		vap->iv_stats.is_ampdu_stop++;
2126 
2127 		ic->ic_addba_stop(ni, tap);
2128 		args[0] = WME_AC_TO_TID(tap->txa_ac);
2129 		args[1] = IEEE80211_DELBAPS_INIT;
2130 		args[2] = reason;			/* XXX reason code */
2131 		ic->ic_send_action(ni, IEEE80211_ACTION_CAT_BA,
2132 			IEEE80211_ACTION_BA_DELBA, args);
2133 	} else {
2134 		IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N,
2135 		    ni, "%s: BA stream for AC %d not running (reason %d)",
2136 		    __func__, tap->txa_ac, reason);
2137 		vap->iv_stats.is_ampdu_stop_failed++;
2138 	}
2139 }
2140 
2141 static void
2142 bar_timeout(void *arg)
2143 {
2144 	struct ieee80211_tx_ampdu *tap = arg;
2145 	struct ieee80211_node *ni = tap->txa_ni;
2146 
2147 	KASSERT((tap->txa_flags & IEEE80211_AGGR_XCHGPEND) == 0,
2148 	    ("bar/addba collision, flags 0x%x", tap->txa_flags));
2149 
2150 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2151 	    ni, "%s: tid %u flags 0x%x attempts %d", __func__,
2152 	    tap->txa_ac, tap->txa_flags, tap->txa_attempts);
2153 
2154 	/* guard against race with bar_tx_complete */
2155 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2156 		return;
2157 	/* XXX ? */
2158 	if (tap->txa_attempts >= ieee80211_bar_maxtries)
2159 		ieee80211_ampdu_stop(ni, tap, IEEE80211_REASON_TIMEOUT);
2160 	else
2161 		ieee80211_send_bar(ni, tap, tap->txa_seqpending);
2162 }
2163 
2164 static void
2165 bar_start_timer(struct ieee80211_tx_ampdu *tap)
2166 {
2167 	callout_reset(&tap->txa_timer, ieee80211_bar_timeout, bar_timeout, tap);
2168 }
2169 
2170 static void
2171 bar_stop_timer(struct ieee80211_tx_ampdu *tap)
2172 {
2173 	callout_stop(&tap->txa_timer);
2174 }
2175 
2176 static void
2177 bar_tx_complete(struct ieee80211_node *ni, void *arg, int status)
2178 {
2179 	struct ieee80211_tx_ampdu *tap = arg;
2180 
2181 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2182 	    ni, "%s: tid %u flags 0x%x pending %d status %d",
2183 	    __func__, tap->txa_ac, tap->txa_flags,
2184 	    callout_pending(&tap->txa_timer), status);
2185 
2186 	/* XXX locking */
2187 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) &&
2188 	    callout_pending(&tap->txa_timer)) {
2189 		struct ieee80211com *ic = ni->ni_ic;
2190 
2191 		if (status)		/* ACK'd */
2192 			bar_stop_timer(tap);
2193 		ic->ic_bar_response(ni, tap, status);
2194 		/* NB: just let timer expire so we pace requests */
2195 	}
2196 }
2197 
2198 static void
2199 ieee80211_bar_response(struct ieee80211_node *ni,
2200 	struct ieee80211_tx_ampdu *tap, int status)
2201 {
2202 
2203 	if (status != 0) {		/* got ACK */
2204 		IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_11N,
2205 		    ni, "BAR moves BA win <%u:%u> (%u frames) txseq %u tid %u",
2206 		    tap->txa_start,
2207 		    IEEE80211_SEQ_ADD(tap->txa_start, tap->txa_wnd-1),
2208 		    tap->txa_qframes, tap->txa_seqpending,
2209 		    WME_AC_TO_TID(tap->txa_ac));
2210 
2211 		/* NB: timer already stopped in bar_tx_complete */
2212 		tap->txa_start = tap->txa_seqpending;
2213 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2214 	}
2215 }
2216 
2217 /*
2218  * Transmit a BAR frame to the specified node.  The
2219  * BAR contents are drawn from the supplied aggregation
2220  * state associated with the node.
2221  *
2222  * NB: we only handle immediate ACK w/ compressed bitmap.
2223  */
2224 int
2225 ieee80211_send_bar(struct ieee80211_node *ni,
2226 	struct ieee80211_tx_ampdu *tap, ieee80211_seq seq)
2227 {
2228 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
2229 	struct ieee80211vap *vap = ni->ni_vap;
2230 	struct ieee80211com *ic = ni->ni_ic;
2231 	struct ieee80211_frame_bar *bar;
2232 	struct mbuf *m;
2233 	uint16_t barctl, barseqctl;
2234 	uint8_t *frm;
2235 	int tid, ret;
2236 
2237 	if ((tap->txa_flags & IEEE80211_AGGR_RUNNING) == 0) {
2238 		/* no ADDBA response, should not happen */
2239 		/* XXX stat+msg */
2240 		return EINVAL;
2241 	}
2242 	/* XXX locking */
2243 	bar_stop_timer(tap);
2244 
2245 	ieee80211_ref_node(ni);
2246 
2247 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom, sizeof(*bar));
2248 	if (m == NULL)
2249 		senderr(ENOMEM, is_tx_nobuf);
2250 
2251 	if (!ieee80211_add_callback(m, bar_tx_complete, tap)) {
2252 		m_freem(m);
2253 		senderr(ENOMEM, is_tx_nobuf);	/* XXX */
2254 		/* NOTREACHED */
2255 	}
2256 
2257 	bar = mtod(m, struct ieee80211_frame_bar *);
2258 	bar->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2259 		IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_BAR;
2260 	bar->i_fc[1] = 0;
2261 	IEEE80211_ADDR_COPY(bar->i_ra, ni->ni_macaddr);
2262 	IEEE80211_ADDR_COPY(bar->i_ta, vap->iv_myaddr);
2263 
2264 	tid = WME_AC_TO_TID(tap->txa_ac);
2265 	barctl 	= (tap->txa_flags & IEEE80211_AGGR_IMMEDIATE ?
2266 			0 : IEEE80211_BAR_NOACK)
2267 		| IEEE80211_BAR_COMP
2268 		| SM(tid, IEEE80211_BAR_TID)
2269 		;
2270 	barseqctl = SM(seq, IEEE80211_BAR_SEQ_START);
2271 	/* NB: known to have proper alignment */
2272 	bar->i_ctl = htole16(barctl);
2273 	bar->i_seq = htole16(barseqctl);
2274 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_bar);
2275 
2276 	M_WME_SETAC(m, WME_AC_VO);
2277 
2278 	IEEE80211_NODE_STAT(ni, tx_mgmt);	/* XXX tx_ctl? */
2279 
2280 	/* XXX locking */
2281 	/* init/bump attempts counter */
2282 	if ((tap->txa_flags & IEEE80211_AGGR_BARPEND) == 0)
2283 		tap->txa_attempts = 1;
2284 	else
2285 		tap->txa_attempts++;
2286 	tap->txa_seqpending = seq;
2287 	tap->txa_flags |= IEEE80211_AGGR_BARPEND;
2288 
2289 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_11N,
2290 	    ni, "send BAR: tid %u ctl 0x%x start %u (attempt %d)",
2291 	    tid, barctl, seq, tap->txa_attempts);
2292 
2293 	ret = ic->ic_raw_xmit(ni, m, NULL);
2294 	if (ret != 0) {
2295 		/* xmit failed, clear state flag */
2296 		tap->txa_flags &= ~IEEE80211_AGGR_BARPEND;
2297 		goto bad;
2298 	}
2299 	/* XXX hack against tx complete happening before timer is started */
2300 	if (tap->txa_flags & IEEE80211_AGGR_BARPEND)
2301 		bar_start_timer(tap);
2302 	return 0;
2303 bad:
2304 	ieee80211_free_node(ni);
2305 	return ret;
2306 #undef senderr
2307 }
2308 
2309 static int
2310 ht_action_output(struct ieee80211_node *ni, struct mbuf *m)
2311 {
2312 	struct ieee80211_bpf_params params;
2313 
2314 	memset(&params, 0, sizeof(params));
2315 	params.ibp_pri = WME_AC_VO;
2316 	params.ibp_rate0 = ni->ni_txparms->mgmtrate;
2317 	/* NB: we know all frames are unicast */
2318 	params.ibp_try0 = ni->ni_txparms->maxretry;
2319 	params.ibp_power = ni->ni_txpower;
2320 	return ieee80211_mgmt_output(ni, m, IEEE80211_FC0_SUBTYPE_ACTION,
2321 	     &params);
2322 }
2323 
2324 #define	ADDSHORT(frm, v) do {			\
2325 	frm[0] = (v) & 0xff;			\
2326 	frm[1] = (v) >> 8;			\
2327 	frm += 2;				\
2328 } while (0)
2329 
2330 /*
2331  * Send an action management frame.  The arguments are stuff
2332  * into a frame without inspection; the caller is assumed to
2333  * prepare them carefully (e.g. based on the aggregation state).
2334  */
2335 static int
2336 ht_send_action_ba_addba(struct ieee80211_node *ni,
2337 	int category, int action, void *arg0)
2338 {
2339 	struct ieee80211vap *vap = ni->ni_vap;
2340 	struct ieee80211com *ic = ni->ni_ic;
2341 	uint16_t *args = arg0;
2342 	struct mbuf *m;
2343 	uint8_t *frm;
2344 
2345 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2346 	    "send ADDBA %s: dialogtoken %d status %d "
2347 	    "baparamset 0x%x (tid %d) batimeout 0x%x baseqctl 0x%x",
2348 	    (action == IEEE80211_ACTION_BA_ADDBA_REQUEST) ?
2349 		"request" : "response",
2350 	    args[0], args[1], args[2], MS(args[2], IEEE80211_BAPS_TID),
2351 	    args[3], args[4]);
2352 
2353 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2354 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2355 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2356 	ieee80211_ref_node(ni);
2357 
2358 	m = ieee80211_getmgtframe(&frm,
2359 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2360 	    sizeof(uint16_t)	/* action+category */
2361 	    /* XXX may action payload */
2362 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2363 	);
2364 	if (m != NULL) {
2365 		*frm++ = category;
2366 		*frm++ = action;
2367 		*frm++ = args[0];		/* dialog token */
2368 		if (action == IEEE80211_ACTION_BA_ADDBA_RESPONSE)
2369 			ADDSHORT(frm, args[1]);	/* status code */
2370 		ADDSHORT(frm, args[2]);		/* baparamset */
2371 		ADDSHORT(frm, args[3]);		/* batimeout */
2372 		if (action == IEEE80211_ACTION_BA_ADDBA_REQUEST)
2373 			ADDSHORT(frm, args[4]);	/* baseqctl */
2374 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2375 		return ht_action_output(ni, m);
2376 	} else {
2377 		vap->iv_stats.is_tx_nobuf++;
2378 		ieee80211_free_node(ni);
2379 		return ENOMEM;
2380 	}
2381 }
2382 
2383 static int
2384 ht_send_action_ba_delba(struct ieee80211_node *ni,
2385 	int category, int action, void *arg0)
2386 {
2387 	struct ieee80211vap *vap = ni->ni_vap;
2388 	struct ieee80211com *ic = ni->ni_ic;
2389 	uint16_t *args = arg0;
2390 	struct mbuf *m;
2391 	uint16_t baparamset;
2392 	uint8_t *frm;
2393 
2394 	baparamset = SM(args[0], IEEE80211_DELBAPS_TID)
2395 		   | args[1]
2396 		   ;
2397 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2398 	    "send DELBA action: tid %d, initiator %d reason %d",
2399 	    args[0], args[1], args[2]);
2400 
2401 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2402 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2403 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2404 	ieee80211_ref_node(ni);
2405 
2406 	m = ieee80211_getmgtframe(&frm,
2407 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2408 	    sizeof(uint16_t)	/* action+category */
2409 	    /* XXX may action payload */
2410 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2411 	);
2412 	if (m != NULL) {
2413 		*frm++ = category;
2414 		*frm++ = action;
2415 		ADDSHORT(frm, baparamset);
2416 		ADDSHORT(frm, args[2]);		/* reason code */
2417 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2418 		return ht_action_output(ni, m);
2419 	} else {
2420 		vap->iv_stats.is_tx_nobuf++;
2421 		ieee80211_free_node(ni);
2422 		return ENOMEM;
2423 	}
2424 }
2425 
2426 static int
2427 ht_send_action_ht_txchwidth(struct ieee80211_node *ni,
2428 	int category, int action, void *arg0)
2429 {
2430 	struct ieee80211vap *vap = ni->ni_vap;
2431 	struct ieee80211com *ic = ni->ni_ic;
2432 	struct mbuf *m;
2433 	uint8_t *frm;
2434 
2435 	IEEE80211_NOTE(vap, IEEE80211_MSG_ACTION | IEEE80211_MSG_11N, ni,
2436 	    "send HT txchwidth: width %d",
2437 	    IEEE80211_IS_CHAN_HT40(ni->ni_chan) ? 40 : 20);
2438 
2439 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2440 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n", __func__, __LINE__,
2441 	    ni, ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)+1);
2442 	ieee80211_ref_node(ni);
2443 
2444 	m = ieee80211_getmgtframe(&frm,
2445 	    ic->ic_headroom + sizeof(struct ieee80211_frame),
2446 	    sizeof(uint16_t)	/* action+category */
2447 	    /* XXX may action payload */
2448 	    + sizeof(struct ieee80211_action_ba_addbaresponse)
2449 	);
2450 	if (m != NULL) {
2451 		*frm++ = category;
2452 		*frm++ = action;
2453 		*frm++ = IEEE80211_IS_CHAN_HT40(ni->ni_chan) ?
2454 			IEEE80211_A_HT_TXCHWIDTH_2040 :
2455 			IEEE80211_A_HT_TXCHWIDTH_20;
2456 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2457 		return ht_action_output(ni, m);
2458 	} else {
2459 		vap->iv_stats.is_tx_nobuf++;
2460 		ieee80211_free_node(ni);
2461 		return ENOMEM;
2462 	}
2463 }
2464 #undef ADDSHORT
2465 
2466 /*
2467  * Construct the MCS bit mask for inclusion in an HT capabilities
2468  * information element.
2469  */
2470 static void
2471 ieee80211_set_mcsset(struct ieee80211com *ic, uint8_t *frm)
2472 {
2473 	int i;
2474 	uint8_t txparams;
2475 
2476 	KASSERT((ic->ic_rxstream > 0 && ic->ic_rxstream <= 4),
2477 	    ("ic_rxstream %d out of range", ic->ic_rxstream));
2478 	KASSERT((ic->ic_txstream > 0 && ic->ic_txstream <= 4),
2479 	    ("ic_txstream %d out of range", ic->ic_txstream));
2480 
2481 	for (i = 0; i < ic->ic_rxstream * 8; i++)
2482 		setbit(frm, i);
2483 	if ((ic->ic_htcaps & IEEE80211_HTCAP_CHWIDTH40) &&
2484 	    (ic->ic_htcaps & IEEE80211_HTC_RXMCS32))
2485 		setbit(frm, 32);
2486 	if (ic->ic_htcaps & IEEE80211_HTC_RXUNEQUAL) {
2487 		if (ic->ic_rxstream >= 2) {
2488 			for (i = 33; i <= 38; i++)
2489 				setbit(frm, i);
2490 		}
2491 		if (ic->ic_rxstream >= 3) {
2492 			for (i = 39; i <= 52; i++)
2493 				setbit(frm, i);
2494 		}
2495 		if (ic->ic_txstream >= 4) {
2496 			for (i = 53; i <= 76; i++)
2497 				setbit(frm, i);
2498 		}
2499 	}
2500 
2501 	if (ic->ic_rxstream != ic->ic_txstream) {
2502 		txparams = 0x1;			/* TX MCS set defined */
2503 		txparams |= 0x2;		/* TX RX MCS not equal */
2504 		txparams |= (ic->ic_txstream - 1) << 2;	/* num TX streams */
2505 		if (ic->ic_htcaps & IEEE80211_HTC_TXUNEQUAL)
2506 			txparams |= 0x16;	/* TX unequal modulation sup */
2507 	} else
2508 		txparams = 0;
2509 	frm[12] = txparams;
2510 }
2511 
2512 /*
2513  * Add body of an HTCAP information element.
2514  */
2515 static uint8_t *
2516 ieee80211_add_htcap_body(uint8_t *frm, struct ieee80211_node *ni)
2517 {
2518 #define	ADDSHORT(frm, v) do {			\
2519 	frm[0] = (v) & 0xff;			\
2520 	frm[1] = (v) >> 8;			\
2521 	frm += 2;				\
2522 } while (0)
2523 	struct ieee80211com *ic = ni->ni_ic;
2524 	struct ieee80211vap *vap = ni->ni_vap;
2525 	uint16_t caps, extcaps;
2526 	int rxmax, density;
2527 
2528 	/* HT capabilities */
2529 	caps = vap->iv_htcaps & 0xffff;
2530 	/*
2531 	 * Note channel width depends on whether we are operating as
2532 	 * a sta or not.  When operating as a sta we are generating
2533 	 * a request based on our desired configuration.  Otherwise
2534 	 * we are operational and the channel attributes identify
2535 	 * how we've been setup (which might be different if a fixed
2536 	 * channel is specified).
2537 	 */
2538 	if (vap->iv_opmode == IEEE80211_M_STA) {
2539 		/* override 20/40 use based on config */
2540 		if (vap->iv_flags_ht & IEEE80211_FHT_USEHT40)
2541 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2542 		else
2543 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2544 		/* use advertised setting (XXX locally constraint) */
2545 		rxmax = MS(ni->ni_htparam, IEEE80211_HTCAP_MAXRXAMPDU);
2546 		density = MS(ni->ni_htparam, IEEE80211_HTCAP_MPDUDENSITY);
2547 
2548 		/*
2549 		 * NB: Hardware might support HT40 on some but not all
2550 		 * channels. We can't determine this earlier because only
2551 		 * after association the channel is upgraded to HT based
2552 		 * on the negotiated capabilities.
2553 		 */
2554 		if (ni->ni_chan != IEEE80211_CHAN_ANYC &&
2555 		    findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT40U) == NULL &&
2556 		    findhtchan(ic, ni->ni_chan, IEEE80211_CHAN_HT40D) == NULL)
2557 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2558 	} else {
2559 		/* override 20/40 use based on current channel */
2560 		if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2561 			caps |= IEEE80211_HTCAP_CHWIDTH40;
2562 		else
2563 			caps &= ~IEEE80211_HTCAP_CHWIDTH40;
2564 		rxmax = vap->iv_ampdu_rxmax;
2565 		density = vap->iv_ampdu_density;
2566 	}
2567 	/* adjust short GI based on channel and config */
2568 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI20) == 0)
2569 		caps &= ~IEEE80211_HTCAP_SHORTGI20;
2570 	if ((vap->iv_flags_ht & IEEE80211_FHT_SHORTGI40) == 0 ||
2571 	    (caps & IEEE80211_HTCAP_CHWIDTH40) == 0)
2572 		caps &= ~IEEE80211_HTCAP_SHORTGI40;
2573 	ADDSHORT(frm, caps);
2574 
2575 	/* HT parameters */
2576 	*frm = SM(rxmax, IEEE80211_HTCAP_MAXRXAMPDU)
2577 	     | SM(density, IEEE80211_HTCAP_MPDUDENSITY)
2578 	     ;
2579 	frm++;
2580 
2581 	/* pre-zero remainder of ie */
2582 	memset(frm, 0, sizeof(struct ieee80211_ie_htcap) -
2583 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset));
2584 
2585 	/* supported MCS set */
2586 	/*
2587 	 * XXX: For sta mode the rate set should be restricted based
2588 	 * on the AP's capabilities, but ni_htrates isn't setup when
2589 	 * we're called to form an AssocReq frame so for now we're
2590 	 * restricted to the device capabilities.
2591 	 */
2592 	ieee80211_set_mcsset(ni->ni_ic, frm);
2593 
2594 	frm += __offsetof(struct ieee80211_ie_htcap, hc_extcap) -
2595 		__offsetof(struct ieee80211_ie_htcap, hc_mcsset);
2596 
2597 	/* HT extended capabilities */
2598 	extcaps = vap->iv_htextcaps & 0xffff;
2599 
2600 	ADDSHORT(frm, extcaps);
2601 
2602 	frm += sizeof(struct ieee80211_ie_htcap) -
2603 		__offsetof(struct ieee80211_ie_htcap, hc_txbf);
2604 
2605 	return frm;
2606 #undef ADDSHORT
2607 }
2608 
2609 /*
2610  * Add 802.11n HT capabilities information element
2611  */
2612 uint8_t *
2613 ieee80211_add_htcap(uint8_t *frm, struct ieee80211_node *ni)
2614 {
2615 	frm[0] = IEEE80211_ELEMID_HTCAP;
2616 	frm[1] = sizeof(struct ieee80211_ie_htcap) - 2;
2617 	return ieee80211_add_htcap_body(frm + 2, ni);
2618 }
2619 
2620 /*
2621  * Add Broadcom OUI wrapped standard HTCAP ie; this is
2622  * used for compatibility w/ pre-draft implementations.
2623  */
2624 uint8_t *
2625 ieee80211_add_htcap_vendor(uint8_t *frm, struct ieee80211_node *ni)
2626 {
2627 	frm[0] = IEEE80211_ELEMID_VENDOR;
2628 	frm[1] = 4 + sizeof(struct ieee80211_ie_htcap) - 2;
2629 	frm[2] = (BCM_OUI >> 0) & 0xff;
2630 	frm[3] = (BCM_OUI >> 8) & 0xff;
2631 	frm[4] = (BCM_OUI >> 16) & 0xff;
2632 	frm[5] = BCM_OUI_HTCAP;
2633 	return ieee80211_add_htcap_body(frm + 6, ni);
2634 }
2635 
2636 /*
2637  * Construct the MCS bit mask of basic rates
2638  * for inclusion in an HT information element.
2639  */
2640 static void
2641 ieee80211_set_basic_htrates(uint8_t *frm, const struct ieee80211_htrateset *rs)
2642 {
2643 	int i;
2644 
2645 	for (i = 0; i < rs->rs_nrates; i++) {
2646 		int r = rs->rs_rates[i] & IEEE80211_RATE_VAL;
2647 		if ((rs->rs_rates[i] & IEEE80211_RATE_BASIC) &&
2648 		    r < IEEE80211_HTRATE_MAXSIZE) {
2649 			/* NB: this assumes a particular implementation */
2650 			setbit(frm, r);
2651 		}
2652 	}
2653 }
2654 
2655 /*
2656  * Update the HTINFO ie for a beacon frame.
2657  */
2658 void
2659 ieee80211_ht_update_beacon(struct ieee80211vap *vap,
2660 	struct ieee80211_beacon_offsets *bo)
2661 {
2662 #define	PROTMODE	(IEEE80211_HTINFO_OPMODE|IEEE80211_HTINFO_NONHT_PRESENT)
2663 	const struct ieee80211_channel *bsschan = vap->iv_bss->ni_chan;
2664 	struct ieee80211com *ic = vap->iv_ic;
2665 	struct ieee80211_ie_htinfo *ht =
2666 	   (struct ieee80211_ie_htinfo *) bo->bo_htinfo;
2667 
2668 	/* XXX only update on channel change */
2669 	ht->hi_ctrlchannel = ieee80211_chan2ieee(ic, bsschan);
2670 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
2671 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PERM;
2672 	else
2673 		ht->hi_byte1 = IEEE80211_HTINFO_RIFSMODE_PROH;
2674 	if (IEEE80211_IS_CHAN_HT40U(bsschan))
2675 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2676 	else if (IEEE80211_IS_CHAN_HT40D(bsschan))
2677 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2678 	else
2679 		ht->hi_byte1 |= IEEE80211_HTINFO_2NDCHAN_NONE;
2680 	if (IEEE80211_IS_CHAN_HT40(bsschan))
2681 		ht->hi_byte1 |= IEEE80211_HTINFO_TXWIDTH_2040;
2682 
2683 	/* protection mode */
2684 	ht->hi_byte2 = (ht->hi_byte2 &~ PROTMODE) | ic->ic_curhtprotmode;
2685 
2686 	/* XXX propagate to vendor ie's */
2687 #undef PROTMODE
2688 }
2689 
2690 /*
2691  * Add body of an HTINFO information element.
2692  *
2693  * NB: We don't use struct ieee80211_ie_htinfo because we can
2694  * be called to fillin both a standard ie and a compat ie that
2695  * has a vendor OUI at the front.
2696  */
2697 static uint8_t *
2698 ieee80211_add_htinfo_body(uint8_t *frm, struct ieee80211_node *ni)
2699 {
2700 	struct ieee80211vap *vap = ni->ni_vap;
2701 	struct ieee80211com *ic = ni->ni_ic;
2702 
2703 	/* pre-zero remainder of ie */
2704 	memset(frm, 0, sizeof(struct ieee80211_ie_htinfo) - 2);
2705 
2706 	/* primary/control channel center */
2707 	*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
2708 
2709 	if (vap->iv_flags_ht & IEEE80211_FHT_RIFS)
2710 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PERM;
2711 	else
2712 		frm[0] = IEEE80211_HTINFO_RIFSMODE_PROH;
2713 	if (IEEE80211_IS_CHAN_HT40U(ni->ni_chan))
2714 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_ABOVE;
2715 	else if (IEEE80211_IS_CHAN_HT40D(ni->ni_chan))
2716 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_BELOW;
2717 	else
2718 		frm[0] |= IEEE80211_HTINFO_2NDCHAN_NONE;
2719 	if (IEEE80211_IS_CHAN_HT40(ni->ni_chan))
2720 		frm[0] |= IEEE80211_HTINFO_TXWIDTH_2040;
2721 
2722 	frm[1] = ic->ic_curhtprotmode;
2723 
2724 	frm += 5;
2725 
2726 	/* basic MCS set */
2727 	ieee80211_set_basic_htrates(frm, &ni->ni_htrates);
2728 	frm += sizeof(struct ieee80211_ie_htinfo) -
2729 		__offsetof(struct ieee80211_ie_htinfo, hi_basicmcsset);
2730 	return frm;
2731 }
2732 
2733 /*
2734  * Add 802.11n HT information information element.
2735  */
2736 uint8_t *
2737 ieee80211_add_htinfo(uint8_t *frm, struct ieee80211_node *ni)
2738 {
2739 	frm[0] = IEEE80211_ELEMID_HTINFO;
2740 	frm[1] = sizeof(struct ieee80211_ie_htinfo) - 2;
2741 	return ieee80211_add_htinfo_body(frm + 2, ni);
2742 }
2743 
2744 /*
2745  * Add Broadcom OUI wrapped standard HTINFO ie; this is
2746  * used for compatibility w/ pre-draft implementations.
2747  */
2748 uint8_t *
2749 ieee80211_add_htinfo_vendor(uint8_t *frm, struct ieee80211_node *ni)
2750 {
2751 	frm[0] = IEEE80211_ELEMID_VENDOR;
2752 	frm[1] = 4 + sizeof(struct ieee80211_ie_htinfo) - 2;
2753 	frm[2] = (BCM_OUI >> 0) & 0xff;
2754 	frm[3] = (BCM_OUI >> 8) & 0xff;
2755 	frm[4] = (BCM_OUI >> 16) & 0xff;
2756 	frm[5] = BCM_OUI_HTINFO;
2757 	return ieee80211_add_htinfo_body(frm + 6, ni);
2758 }
2759