xref: /freebsd/sys/dev/rtwn/rtl8812a/r12a_tx.c (revision dd21556857e8d40f66bf5ad54754d9d52669ebf7)
1 /*-
2  * Copyright (c) 2016 Andriy Voskoboinyk <avos@FreeBSD.org>
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 AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 #include "opt_wlan.h"
29 
30 #include <sys/param.h>
31 #include <sys/lock.h>
32 #include <sys/mutex.h>
33 #include <sys/mbuf.h>
34 #include <sys/kernel.h>
35 #include <sys/socket.h>
36 #include <sys/systm.h>
37 #include <sys/malloc.h>
38 #include <sys/queue.h>
39 #include <sys/taskqueue.h>
40 #include <sys/bus.h>
41 #include <sys/endian.h>
42 #include <sys/linker.h>
43 
44 #include <net/if.h>
45 #include <net/ethernet.h>
46 #include <net/if_media.h>
47 
48 #include <net80211/ieee80211_var.h>
49 #include <net80211/ieee80211_radiotap.h>
50 #include <net80211/ieee80211_vht.h>
51 
52 #include <dev/rtwn/if_rtwnreg.h>
53 #include <dev/rtwn/if_rtwnvar.h>
54 
55 #include <dev/rtwn/if_rtwn_ridx.h>
56 
57 #include <dev/rtwn/rtl8812a/r12a.h>
58 #include <dev/rtwn/rtl8812a/r12a_tx_desc.h>
59 
60 /*
61  * This function actually handles the secondary channel mapping,
62  * not the primary channel mapping.  It hints to the MAC where
63  * to handle duplicate transmission of the RTS/CTS and payload
64  * frames when the requested transmit channel width is less than
65  * the configured channel width.
66  *
67  * Note: the vendor driver and linux rtw88 driver both leave this
68  * field currently set to 0.
69  *
70  * See the rtl8812au vendor driver, hal/rtl8812a_xmit.c:SCMapping_8812()
71  * and where it's used (and ignored.)
72  */
73 static int
74 r12a_get_primary_channel(struct rtwn_softc *sc, struct ieee80211_channel *c)
75 {
76 #if 0
77 	/* XXX VHT80; VHT40 */
78 	if (IEEE80211_IS_CHAN_HT40U(c))
79 		return (R12A_TXDW5_PRIM_CHAN_20_80_2);
80 	else
81 		return (R12A_TXDW5_PRIM_CHAN_20_80_3);
82 #endif
83 
84 	/*
85 	 * For now just return the VHT_DATA_SC_DONOT_CARE value
86 	 * from the reference driver.
87 	 */
88 	return (0);
89 }
90 
91 /*
92  * Configure VHT20/VHT40/VHT80 as appropriate.
93  *
94  * This is only called for VHT, not for HT.
95  */
96 static void
97 r12a_tx_set_vht_bw(struct rtwn_softc *sc, void *buf, struct ieee80211_node *ni)
98 {
99 	struct r12a_tx_desc *txd = (struct r12a_tx_desc *)buf;
100 	int prim_chan;
101 
102 	prim_chan = r12a_get_primary_channel(sc, ni->ni_chan);
103 
104 	if (ieee80211_vht_check_tx_bw(ni, IEEE80211_STA_RX_BW_80)) {
105 		txd->txdw5 |= htole32(SM(R12A_TXDW5_DATA_BW,
106 		    R12A_TXDW5_DATA_BW80));
107 		txd->txdw5 |= htole32(SM(R12A_TXDW5_DATA_PRIM_CHAN,
108 		    prim_chan));
109 	} else if (ieee80211_vht_check_tx_bw(ni, IEEE80211_STA_RX_BW_40)) {
110 		txd->txdw5 |= htole32(SM(R12A_TXDW5_DATA_BW,
111 		    R12A_TXDW5_DATA_BW40));
112 		txd->txdw5 |= htole32(SM(R12A_TXDW5_DATA_PRIM_CHAN,
113 		    prim_chan));
114 	}
115 }
116 
117 /*
118  * Configure HT20/HT40 as appropriate.
119  *
120  * This is only called for HT, not for VHT.
121  */
122 static void
123 r12a_tx_set_ht40(struct rtwn_softc *sc, void *buf, struct ieee80211_node *ni)
124 {
125 	struct r12a_tx_desc *txd = (struct r12a_tx_desc *)buf;
126 
127 	if (ieee80211_ht_check_tx_ht40(ni)) {
128 		int prim_chan;
129 
130 		prim_chan = r12a_get_primary_channel(sc, ni->ni_chan);
131 		txd->txdw5 |= htole32(SM(R12A_TXDW5_DATA_BW,
132 		    R12A_TXDW5_DATA_BW40));
133 		txd->txdw5 |= htole32(SM(R12A_TXDW5_DATA_PRIM_CHAN,
134 		    prim_chan));
135 	}
136 }
137 
138 static void
139 r12a_tx_protection(struct rtwn_softc *sc, struct r12a_tx_desc *txd,
140     enum ieee80211_protmode mode, uint8_t ridx)
141 {
142 	struct ieee80211com *ic = &sc->sc_ic;
143 	uint8_t rate;
144 
145 	switch (mode) {
146 	case IEEE80211_PROT_CTSONLY:
147 		txd->txdw3 |= htole32(R12A_TXDW3_CTS2SELF);
148 		break;
149 	case IEEE80211_PROT_RTSCTS:
150 		txd->txdw3 |= htole32(R12A_TXDW3_RTSEN);
151 		break;
152 	default:
153 		break;
154 	}
155 
156 	if (mode == IEEE80211_PROT_CTSONLY ||
157 	    mode == IEEE80211_PROT_RTSCTS) {
158 		/*
159 		 * Note: this code assumes basic rates for protection for
160 		 * both 802.11abg and 802.11n rates.
161 		 */
162 		if (RTWN_RATE_IS_VHT(ridx))
163 			rate = rtwn_ctl_vhtrate(ic->ic_rt, ridx);
164 		else if (RTWN_RATE_IS_HT(ridx))
165 			rate = rtwn_ctl_mcsrate(ic->ic_rt, ridx);
166 		else
167 			rate = ieee80211_ctl_rate(ic->ic_rt, ridx2rate[ridx]);
168 		/* Map basic rate back to ridx */
169 		ridx = rate2ridx(IEEE80211_RV(rate));
170 
171 		txd->txdw4 |= htole32(SM(R12A_TXDW4_RTSRATE, ridx));
172 		/* RTS rate fallback limit (max). */
173 		txd->txdw4 |= htole32(SM(R12A_TXDW4_RTSRATE_FB_LMT, 0xf));
174 
175 		if (RTWN_RATE_IS_CCK(ridx) && ridx != RTWN_RIDX_CCK1 &&
176 		    (ic->ic_flags & IEEE80211_F_SHPREAMBLE))
177 			txd->txdw5 |= htole32(R12A_TXDW5_RTS_SHORT);
178 	}
179 }
180 
181 static void
182 r12a_tx_raid(struct rtwn_softc *sc, struct r12a_tx_desc *txd,
183     struct ieee80211_node *ni, int ismcast)
184 {
185 	struct ieee80211com *ic = &sc->sc_ic;
186 	struct ieee80211vap *vap = ni->ni_vap;
187 	struct ieee80211_channel *chan;
188 	enum ieee80211_phymode mode;
189 	uint8_t raid;
190 
191 	chan = (ni->ni_chan != IEEE80211_CHAN_ANYC) ?
192 		ni->ni_chan : ic->ic_curchan;
193 	mode = ieee80211_chan2mode(chan);
194 
195 	/* NB: group addressed frames are done at 11bg rates for now */
196 	if (ismcast || !(ni->ni_flags & IEEE80211_NODE_HT)) {
197 		switch (mode) {
198 		case IEEE80211_MODE_11A:
199 		case IEEE80211_MODE_11B:
200 		case IEEE80211_MODE_11G:
201 			break;
202 		case IEEE80211_MODE_11NA:
203 			mode = IEEE80211_MODE_11A;
204 			break;
205 		case IEEE80211_MODE_11NG:
206 			mode = IEEE80211_MODE_11G;
207 			break;
208 		case IEEE80211_MODE_VHT_5GHZ:
209 			mode = IEEE80211_MODE_VHT_5GHZ;
210 			break;
211 		default:
212 			device_printf(sc->sc_dev, "unknown mode(1) %d!\n",
213 			    ic->ic_curmode);
214 			return;
215 		}
216 	}
217 
218 	switch (mode) {
219 	case IEEE80211_MODE_11A:
220 		raid = R12A_RAID_11G;
221 		break;
222 	case IEEE80211_MODE_11B:
223 		raid = R12A_RAID_11B;
224 		break;
225 	case IEEE80211_MODE_11G:
226 		if (vap->iv_flags & IEEE80211_F_PUREG)
227 			raid = R12A_RAID_11G;
228 		else
229 			raid = R12A_RAID_11BG;
230 		break;
231 	case IEEE80211_MODE_11NA:
232 		if (sc->ntxchains == 1)
233 			raid = R12A_RAID_11GN_1;
234 		else
235 			raid = R12A_RAID_11GN_2;
236 		break;
237 	case IEEE80211_MODE_11NG:
238 		if (sc->ntxchains == 1) {
239 			if (IEEE80211_IS_CHAN_HT40(chan))
240 				raid = R12A_RAID_11BGN_1_40;
241 			else
242 				raid = R12A_RAID_11BGN_1;
243 		} else {
244 			if (IEEE80211_IS_CHAN_HT40(chan))
245 				raid = R12A_RAID_11BGN_2_40;
246 			else
247 				raid = R12A_RAID_11BGN_2;
248 		}
249 		break;
250 	case IEEE80211_MODE_VHT_5GHZ:
251 		if (sc->ntxchains == 1)
252 			raid = R12A_RAID_11AC_1;
253 		else
254 			raid = R12A_RAID_11AC_2;
255 		break;
256 	default:
257 		device_printf(sc->sc_dev, "unknown mode(2) %d!\n", mode);
258 		return;
259 	}
260 
261 	txd->txdw1 |= htole32(SM(R12A_TXDW1_RAID, raid));
262 }
263 
264 static void
265 r12a_tx_set_sgi(struct rtwn_softc *sc, void *buf, struct ieee80211_node *ni)
266 {
267 	struct r12a_tx_desc *txd = (struct r12a_tx_desc *)buf;
268 
269 	/* TODO: VHT 20/40/80 checks */
270 
271 	/*
272 	 * Only enable short-GI if we're transmitting in that
273 	 * width to that node.
274 	 *
275 	 * Specifically, do not enable shortgi for 20MHz if
276 	 * we're attempting to transmit at 40MHz.
277 	 */
278 	if (ieee80211_ht_check_tx_ht40(ni)) {
279 		if (ieee80211_ht_check_tx_shortgi_40(ni))
280 			txd->txdw5 |= htole32(R12A_TXDW5_DATA_SHORT);
281 	} else if (ieee80211_ht_check_tx_ht(ni)) {
282 		if (ieee80211_ht_check_tx_shortgi_20(ni))
283 			txd->txdw5 |= htole32(R12A_TXDW5_DATA_SHORT);
284 	}
285 }
286 
287 static void
288 r12a_tx_set_ldpc(struct rtwn_softc *sc, struct r12a_tx_desc *txd,
289     struct ieee80211_node *ni)
290 {
291 	struct ieee80211vap *vap = ni->ni_vap;
292 
293 	if ((vap->iv_flags_ht & IEEE80211_FHT_LDPC_TX) &&
294 	    (ni->ni_htcap & IEEE80211_HTCAP_LDPC))
295 		txd->txdw5 |= htole32(R12A_TXDW5_DATA_LDPC);
296 }
297 
298 static int
299 r12a_calculate_tx_agg_window(struct rtwn_softc *sc,
300     const struct ieee80211_node *ni, int tid)
301 {
302 	const struct ieee80211_tx_ampdu *tap;
303 	int wnd;
304 
305 	tap = &ni->ni_tx_ampdu[tid];
306 
307 	/*
308 	 * BAW is (MAX_AGG * 2) + 1, hence the /2 here.
309 	 * Ensure we don't send 0 or more than 64.
310 	 */
311 	wnd = tap->txa_wnd / 2;
312 	if (wnd == 0)
313 		wnd = 1;
314 	else if (wnd > 0x1f)
315 		wnd = 0x1f;
316 
317 	return (wnd);
318 }
319 
320 void
321 r12a_fill_tx_desc(struct rtwn_softc *sc, struct ieee80211_node *ni,
322     struct mbuf *m, void *buf, uint8_t ridx, bool force_rate, int maxretry)
323 {
324 	struct ieee80211com *ic = &sc->sc_ic;
325 	struct ieee80211vap *vap = ni->ni_vap;
326 	struct rtwn_vap *uvp = RTWN_VAP(vap);
327 	struct ieee80211_frame *wh;
328 	struct r12a_tx_desc *txd;
329 	enum ieee80211_protmode prot;
330 	uint8_t type, tid, qos, qsel;
331 	int hasqos, ismcast, macid;
332 
333 	wh = mtod(m, struct ieee80211_frame *);
334 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
335 	hasqos = IEEE80211_QOS_HAS_SEQ(wh);
336 	ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
337 
338 	/* Select TX ring for this frame. */
339 	if (hasqos) {
340 		qos = ((const struct ieee80211_qosframe *)wh)->i_qos[0];
341 		tid = qos & IEEE80211_QOS_TID;
342 	} else {
343 		qos = 0;
344 		tid = 0;
345 	}
346 
347 	/* Fill Tx descriptor. */
348 	txd = (struct r12a_tx_desc *)buf;
349 	txd->flags0 |= R12A_FLAGS0_LSG | R12A_FLAGS0_FSG;
350 	if (ismcast)
351 		txd->flags0 |= R12A_FLAGS0_BMCAST;
352 
353 	if (!ismcast) {
354 		/* Unicast frame, check if an ACK is expected. */
355 		if (!qos || (qos & IEEE80211_QOS_ACKPOLICY) !=
356 		    IEEE80211_QOS_ACKPOLICY_NOACK) {
357 			txd->txdw4 = htole32(R12A_TXDW4_RETRY_LMT_ENA);
358 			txd->txdw4 |= htole32(SM(R12A_TXDW4_RETRY_LMT,
359 			    maxretry));
360 		}
361 
362 		struct rtwn_node *un = RTWN_NODE(ni);
363 		macid = un->id;
364 
365 		if (type == IEEE80211_FC0_TYPE_DATA) {
366 			qsel = tid % RTWN_MAX_TID;
367 
368 			if (m->m_flags & M_AMPDU_MPDU) {
369 				txd->txdw2 |= htole32(R12A_TXDW2_AGGEN);
370 				txd->txdw2 |= htole32(SM(R12A_TXDW2_AMPDU_DEN,
371 				    ieee80211_ht_get_node_ampdu_density(ni)));
372 				txd->txdw3 |= htole32(SM(R12A_TXDW3_MAX_AGG,
373 				    r12a_calculate_tx_agg_window(sc, ni, tid)));
374 			} else
375 				txd->txdw2 |= htole32(R12A_TXDW2_AGGBK);
376 
377 			if (sc->sc_ratectl == RTWN_RATECTL_NET80211) {
378 				txd->txdw2 |= htole32(R12A_TXDW2_SPE_RPT);
379 				sc->sc_tx_n_active++;
380 			}
381 
382 			if (RTWN_RATE_IS_CCK(ridx) && ridx != RTWN_RIDX_CCK1 &&
383 			    (ic->ic_flags & IEEE80211_F_SHPREAMBLE))
384 				txd->txdw5 |= htole32(R12A_TXDW5_DATA_SHORT);
385 
386 			prot = IEEE80211_PROT_NONE;
387 			if (RTWN_RATE_IS_VHT(ridx)) {
388 				r12a_tx_set_vht_bw(sc, txd, ni);
389 				/* XXX TODO: sgi */
390 				/* XXX TODO: ldpc */
391 				prot = ic->ic_htprotmode;
392 			} else if (RTWN_RATE_IS_HT(ridx)) {
393 				r12a_tx_set_ht40(sc, txd, ni);
394 				r12a_tx_set_sgi(sc, txd, ni);
395 				r12a_tx_set_ldpc(sc, txd, ni);
396 				prot = ic->ic_htprotmode;
397 			} else if (ic->ic_flags & IEEE80211_F_USEPROT)
398 				prot = ic->ic_protmode;
399 
400 			/* XXX fix last comparison for A-MSDU (in net80211) */
401 			/* XXX A-MPDU? */
402 			if (m->m_pkthdr.len + IEEE80211_CRC_LEN >
403 			    vap->iv_rtsthreshold &&
404 			    vap->iv_rtsthreshold != IEEE80211_RTS_MAX)
405 				prot = IEEE80211_PROT_RTSCTS;
406 
407 			if (prot != IEEE80211_PROT_NONE)
408 				r12a_tx_protection(sc, txd, prot, ridx);
409 		} else	/* IEEE80211_FC0_TYPE_MGT */
410 			qsel = R12A_TXDW1_QSEL_MGNT;
411 	} else {
412 		macid = RTWN_MACID_BC;
413 		qsel = R12A_TXDW1_QSEL_MGNT;
414 	}
415 
416 	txd->txdw1 |= htole32(SM(R12A_TXDW1_QSEL, qsel));
417 	txd->txdw1 |= htole32(SM(R12A_TXDW1_MACID, macid));
418 	txd->txdw4 |= htole32(SM(R12A_TXDW4_DATARATE, ridx));
419 	/* Data rate fallback limit (max). */
420 	txd->txdw4 |= htole32(SM(R12A_TXDW4_DATARATE_FB_LMT, 0x1f));
421 	/* XXX recheck for non-21au */
422 	txd->txdw6 |= htole32(SM(R21A_TXDW6_MBSSID, uvp->id));
423 	r12a_tx_raid(sc, txd, ni, ismcast);
424 
425 	/* Force this rate if needed. */
426 	if (sc->sc_ratectl != RTWN_RATECTL_FW)
427 		txd->txdw3 |= htole32(R12A_TXDW3_DRVRATE);
428 
429 	if (!hasqos) {
430 		/* Use HW sequence numbering for non-QoS frames. */
431 		txd->txdw8 |= htole32(R12A_TXDW8_HWSEQ_EN);
432 		txd->txdw3 |= htole32(SM(R12A_TXDW3_SEQ_SEL, uvp->id));
433 	} else {
434 		uint16_t seqno;
435 
436 		if (m->m_flags & M_AMPDU_MPDU) {
437 			seqno = ni->ni_txseqs[tid];
438 			ni->ni_txseqs[tid]++;
439 		} else
440 			seqno = M_SEQNO_GET(m) % IEEE80211_SEQ_RANGE;
441 
442 		/* Set sequence number. */
443 		txd->txdw9 |= htole32(SM(R12A_TXDW9_SEQ, seqno));
444 	}
445 }
446 
447 void
448 r12a_fill_tx_desc_raw(struct rtwn_softc *sc, struct ieee80211_node *ni,
449     struct mbuf *m, void *buf, const struct ieee80211_bpf_params *params)
450 {
451 	struct ieee80211vap *vap = ni->ni_vap;
452 	struct rtwn_vap *uvp = RTWN_VAP(vap);
453 	struct ieee80211_frame *wh;
454 	struct r12a_tx_desc *txd;
455 	uint8_t ridx;
456 	int ismcast;
457 
458 	/* XXX TODO: 11n checks, matching rtwn_fill_tx_desc() */
459 
460 	wh = mtod(m, struct ieee80211_frame *);
461 	ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
462 	ridx = rate2ridx(params->ibp_rate0);
463 
464 	/* Fill Tx descriptor. */
465 	txd = (struct r12a_tx_desc *)buf;
466 	txd->flags0 |= R12A_FLAGS0_LSG | R12A_FLAGS0_FSG;
467 	if (ismcast)
468 		txd->flags0 |= R12A_FLAGS0_BMCAST;
469 
470 	if ((params->ibp_flags & IEEE80211_BPF_NOACK) == 0) {
471 		txd->txdw4 = htole32(R12A_TXDW4_RETRY_LMT_ENA);
472 		txd->txdw4 |= htole32(SM(R12A_TXDW4_RETRY_LMT,
473 		    params->ibp_try0));
474 	}
475 	if (params->ibp_flags & IEEE80211_BPF_RTS)
476 		r12a_tx_protection(sc, txd, IEEE80211_PROT_RTSCTS, ridx);
477 	if (params->ibp_flags & IEEE80211_BPF_CTS)
478 		r12a_tx_protection(sc, txd, IEEE80211_PROT_CTSONLY, ridx);
479 
480 	txd->txdw1 |= htole32(SM(R12A_TXDW1_MACID, RTWN_MACID_BC));
481 	txd->txdw1 |= htole32(SM(R12A_TXDW1_QSEL, R12A_TXDW1_QSEL_MGNT));
482 
483 	/* Set TX rate index. */
484 	txd->txdw4 |= htole32(SM(R12A_TXDW4_DATARATE, ridx));
485 	txd->txdw4 |= htole32(SM(R12A_TXDW4_DATARATE_FB_LMT, 0x1f));
486 	txd->txdw6 |= htole32(SM(R21A_TXDW6_MBSSID, uvp->id));
487 	txd->txdw3 |= htole32(R12A_TXDW3_DRVRATE);
488 	r12a_tx_raid(sc, txd, ni, ismcast);
489 
490 	if (!IEEE80211_QOS_HAS_SEQ(wh)) {
491 		/* Use HW sequence numbering for non-QoS frames. */
492 		txd->txdw8 |= htole32(R12A_TXDW8_HWSEQ_EN);
493 		txd->txdw3 |= htole32(SM(R12A_TXDW3_SEQ_SEL, uvp->id));
494 	} else {
495 		/* Set sequence number. */
496 		txd->txdw9 |= htole32(SM(R12A_TXDW9_SEQ,
497 		    M_SEQNO_GET(m) % IEEE80211_SEQ_RANGE));
498 	}
499 }
500 
501 void
502 r12a_fill_tx_desc_null(struct rtwn_softc *sc, void *buf, int is11b, int qos,
503     int id)
504 {
505 	struct r12a_tx_desc *txd = (struct r12a_tx_desc *)buf;
506 
507 	txd->flags0 = R12A_FLAGS0_FSG | R12A_FLAGS0_LSG | R12A_FLAGS0_OWN;
508 	txd->txdw1 = htole32(
509 	    SM(R12A_TXDW1_QSEL, R12A_TXDW1_QSEL_MGNT));
510 
511 	txd->txdw3 = htole32(R12A_TXDW3_DRVRATE);
512 	txd->txdw6 = htole32(SM(R21A_TXDW6_MBSSID, id));
513 	if (is11b) {
514 		txd->txdw4 = htole32(SM(R12A_TXDW4_DATARATE,
515 		    RTWN_RIDX_CCK1));
516 	} else {
517 		txd->txdw4 = htole32(SM(R12A_TXDW4_DATARATE,
518 		    RTWN_RIDX_OFDM6));
519 	}
520 
521 	if (!qos) {
522 		txd->txdw8 = htole32(R12A_TXDW8_HWSEQ_EN);
523 		txd->txdw3 |= htole32(SM(R12A_TXDW3_SEQ_SEL, id));
524 	}
525 }
526 
527 uint8_t
528 r12a_tx_radiotap_flags(const void *buf)
529 {
530 	const struct r12a_tx_desc *txd = buf;
531 	uint8_t flags, rate;
532 
533 	if (!(txd->txdw5 & htole32(R12A_TXDW5_DATA_SHORT)))
534 		return (0);
535 
536 	rate = MS(le32toh(txd->txdw4), R12A_TXDW4_DATARATE);
537 	if (RTWN_RATE_IS_CCK(rate))
538 		flags = IEEE80211_RADIOTAP_F_SHORTPRE;
539 	else
540 		flags = IEEE80211_RADIOTAP_F_SHORTGI;
541 	return (flags);
542 }
543