2 * Copyright (c) 2011 Adrian Chadd, Xenion Pty Ltd.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer,
10 * without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
13 * redistribution must be conditioned upon including a substantially
14 * similar Disclaimer requirement for further binary redistribution.
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
20 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
22 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
25 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
27 * THE POSSIBILITY OF SUCH DAMAGES.
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/sysctl.h>
41 #include <sys/malloc.h>
43 #include <sys/mutex.h>
44 #include <sys/kernel.h>
45 #include <sys/socket.h>
46 #include <sys/sockio.h>
47 #include <sys/errno.h>
48 #include <sys/callout.h>
50 #include <sys/endian.h>
51 #include <sys/kthread.h>
52 #include <sys/taskqueue.h>
56 #include <net/if_dl.h>
57 #include <net/if_media.h>
58 #include <net/if_types.h>
59 #include <net/if_arp.h>
60 #include <net/ethernet.h>
61 #include <net/if_llc.h>
63 #include <netproto/802_11/ieee80211_var.h>
64 #include <netproto/802_11/ieee80211_regdomain.h>
65 #ifdef IEEE80211_SUPPORT_SUPERG
66 #include <netproto/802_11/ieee80211_superg.h>
68 #ifdef IEEE80211_SUPPORT_TDMA
69 #include <netproto/802_11/ieee80211_tdma.h>
75 #include <netinet/in.h>
76 #include <netinet/if_ether.h>
79 #include <dev/netif/ath/ath/if_athvar.h>
80 #include <dev/netif/ath/ath_hal/ah_devid.h> /* XXX for softled */
81 #include <dev/netif/ath/ath_hal/ah_diagcodes.h>
84 #include <dev/netif/ath/ath_tx99/ath_tx99.h>
87 #include <dev/netif/ath/ath/if_ath_tx.h> /* XXX for some support functions */
88 #include <dev/netif/ath/ath/if_ath_tx_ht.h>
89 #include <dev/netif/ath/ath/if_athrate.h>
90 #include <dev/netif/ath/ath/if_ath_debug.h>
95 #define IEEE80211_AMPDU_SUBFRAME_DEFAULT 32
97 #define ATH_AGGR_DELIM_SZ 4 /* delimiter size */
98 #define ATH_AGGR_MINPLEN 256 /* in bytes, minimum packet length */
99 /* number of delimiters for encryption padding */
100 #define ATH_AGGR_ENCRYPTDELIM 10
103 * returns delimiter padding required given the packet length
105 #define ATH_AGGR_GET_NDELIM(_len) \
106 (((((_len) + ATH_AGGR_DELIM_SZ) < ATH_AGGR_MINPLEN) ? \
107 (ATH_AGGR_MINPLEN - (_len) - ATH_AGGR_DELIM_SZ) : 0) >> 2)
109 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
111 int ath_max_4ms_framelen[4][32] = {
113 3212, 6432, 9648, 12864, 19300, 25736, 28952, 32172,
114 6424, 12852, 19280, 25708, 38568, 51424, 57852, 64280,
115 9628, 19260, 28896, 38528, 57792, 65532, 65532, 65532,
116 12828, 25656, 38488, 51320, 65532, 65532, 65532, 65532,
119 3572, 7144, 10720, 14296, 21444, 28596, 32172, 35744,
120 7140, 14284, 21428, 28568, 42856, 57144, 64288, 65532,
121 10700, 21408, 32112, 42816, 64228, 65532, 65532, 65532,
122 14256, 28516, 42780, 57040, 65532, 65532, 65532, 65532,
125 6680, 13360, 20044, 26724, 40092, 53456, 60140, 65532,
126 13348, 26700, 40052, 53400, 65532, 65532, 65532, 65532,
127 20004, 40008, 60016, 65532, 65532, 65532, 65532, 65532,
128 26644, 53292, 65532, 65532, 65532, 65532, 65532, 65532,
131 7420, 14844, 22272, 29696, 44544, 59396, 65532, 65532,
132 14832, 29668, 44504, 59340, 65532, 65532, 65532, 65532,
133 22232, 44464, 65532, 65532, 65532, 65532, 65532, 65532,
134 29616, 59232, 65532, 65532, 65532, 65532, 65532, 65532,
139 * XXX should be in net80211
141 static int ieee80211_mpdudensity_map[] = {
142 0, /* IEEE80211_HTCAP_MPDUDENSITY_NA */
143 25, /* IEEE80211_HTCAP_MPDUDENSITY_025 */
144 50, /* IEEE80211_HTCAP_MPDUDENSITY_05 */
145 100, /* IEEE80211_HTCAP_MPDUDENSITY_1 */
146 200, /* IEEE80211_HTCAP_MPDUDENSITY_2 */
147 400, /* IEEE80211_HTCAP_MPDUDENSITY_4 */
148 800, /* IEEE80211_HTCAP_MPDUDENSITY_8 */
149 1600, /* IEEE80211_HTCAP_MPDUDENSITY_16 */
153 * XXX should be in the HAL/net80211 ?
155 #define BITS_PER_BYTE 8
156 #define OFDM_PLCP_BITS 22
157 #define HT_RC_2_MCS(_rc) ((_rc) & 0x7f)
158 #define HT_RC_2_STREAMS(_rc) ((((_rc) & 0x78) >> 3) + 1)
164 #define HT_LTF(_ns) (4 * (_ns))
165 #define SYMBOL_TIME(_ns) ((_ns) << 2) // ns * 4 us
166 #define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5) // ns * 3.6 us
167 #define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
168 #define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
169 #define IS_HT_RATE(_rate) ((_rate) & 0x80)
171 const uint32_t bits_per_symbol[][2] = {
173 { 26, 54 }, // 0: BPSK
174 { 52, 108 }, // 1: QPSK 1/2
175 { 78, 162 }, // 2: QPSK 3/4
176 { 104, 216 }, // 3: 16-QAM 1/2
177 { 156, 324 }, // 4: 16-QAM 3/4
178 { 208, 432 }, // 5: 64-QAM 2/3
179 { 234, 486 }, // 6: 64-QAM 3/4
180 { 260, 540 }, // 7: 64-QAM 5/6
181 { 52, 108 }, // 8: BPSK
182 { 104, 216 }, // 9: QPSK 1/2
183 { 156, 324 }, // 10: QPSK 3/4
184 { 208, 432 }, // 11: 16-QAM 1/2
185 { 312, 648 }, // 12: 16-QAM 3/4
186 { 416, 864 }, // 13: 64-QAM 2/3
187 { 468, 972 }, // 14: 64-QAM 3/4
188 { 520, 1080 }, // 15: 64-QAM 5/6
189 { 78, 162 }, // 16: BPSK
190 { 156, 324 }, // 17: QPSK 1/2
191 { 234, 486 }, // 18: QPSK 3/4
192 { 312, 648 }, // 19: 16-QAM 1/2
193 { 468, 972 }, // 20: 16-QAM 3/4
194 { 624, 1296 }, // 21: 64-QAM 2/3
195 { 702, 1458 }, // 22: 64-QAM 3/4
196 { 780, 1620 }, // 23: 64-QAM 5/6
197 { 104, 216 }, // 24: BPSK
198 { 208, 432 }, // 25: QPSK 1/2
199 { 312, 648 }, // 26: QPSK 3/4
200 { 416, 864 }, // 27: 16-QAM 1/2
201 { 624, 1296 }, // 28: 16-QAM 3/4
202 { 832, 1728 }, // 29: 64-QAM 2/3
203 { 936, 1944 }, // 30: 64-QAM 3/4
204 { 1040, 2160 }, // 31: 64-QAM 5/6
208 * Fill in the rate array information based on the current
209 * node configuration and the choices made by the rate
210 * selection code and ath_buf setup code.
212 * Later on, this may end up also being made by the
213 * rate control code, but for now it can live here.
215 * This needs to be called just before the packet is
216 * queued to the software queue or hardware queue,
217 * so all of the needed fields in bf_state are setup.
220 ath_tx_rate_fill_rcflags(struct ath_softc *sc, struct ath_buf *bf)
222 struct ieee80211_node *ni = bf->bf_node;
223 struct ieee80211com *ic = ni->ni_ic;
224 const HAL_RATE_TABLE *rt = sc->sc_currates;
225 struct ath_rc_series *rc = bf->bf_state.bfs_rc;
229 for (i = 0; i < ATH_RC_NUM; i++) {
231 if (rc[i].tries == 0)
234 rate = rt->info[rc[i].rix].rateCode;
237 * Only enable short preamble for legacy rates
239 if ((! IS_HT_RATE(rate)) && bf->bf_state.bfs_shpream)
240 rate |= rt->info[rc[i].rix].shortPreamble;
243 * Save this, used by the TX and completion code
245 rc[i].ratecode = rate;
247 if (bf->bf_state.bfs_txflags &
248 (HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA))
249 rc[i].flags |= ATH_RC_RTSCTS_FLAG;
251 /* Only enable shortgi, 2040, dual-stream if HT is set */
252 if (IS_HT_RATE(rate)) {
253 rc[i].flags |= ATH_RC_HT_FLAG;
255 if (ni->ni_chw == 40)
256 rc[i].flags |= ATH_RC_CW40_FLAG;
258 if (ni->ni_chw == 40 &&
259 ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI40 &&
260 ni->ni_htcap & IEEE80211_HTCAP_SHORTGI40)
261 rc[i].flags |= ATH_RC_SGI_FLAG;
263 if (ni->ni_chw == 20 &&
264 ic->ic_htcaps & IEEE80211_HTCAP_SHORTGI20 &&
265 ni->ni_htcap & IEEE80211_HTCAP_SHORTGI20)
266 rc[i].flags |= ATH_RC_SGI_FLAG;
269 * If we have STBC TX enabled and the receiver
270 * can receive (at least) 1 stream STBC, AND it's
271 * MCS 0-7, AND we have at least two chains enabled,
274 if (ic->ic_htcaps & IEEE80211_HTCAP_TXSTBC &&
275 ni->ni_htcap & IEEE80211_HTCAP_RXSTBC_1STREAM &&
276 (sc->sc_cur_txchainmask > 1) &&
277 HT_RC_2_STREAMS(rate) == 1) {
278 rc[i].flags |= ATH_RC_STBC_FLAG;
286 * Dual / Triple stream rate?
288 if (HT_RC_2_STREAMS(rate) == 2)
289 rc[i].flags |= ATH_RC_DS_FLAG;
290 else if (HT_RC_2_STREAMS(rate) == 3)
291 rc[i].flags |= ATH_RC_TS_FLAG;
295 * Calculate the maximum TX power cap for the current
298 rc[i].tx_power_cap = ieee80211_get_node_txpower(ni);
301 * Calculate the maximum 4ms frame length based
302 * on the MCS rate, SGI and channel width flags.
304 if ((rc[i].flags & ATH_RC_HT_FLAG) &&
305 (HT_RC_2_MCS(rate) < 32)) {
307 if (rc[i].flags & ATH_RC_CW40_FLAG) {
308 if (rc[i].flags & ATH_RC_SGI_FLAG)
313 if (rc[i].flags & ATH_RC_SGI_FLAG)
318 rc[i].max4msframelen =
319 ath_max_4ms_framelen[j][HT_RC_2_MCS(rate)];
321 rc[i].max4msframelen = 0;
322 DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
323 "%s: i=%d, rate=0x%x, flags=0x%x, max4ms=%d\n",
324 __func__, i, rate, rc[i].flags, rc[i].max4msframelen);
329 * Return the number of delimiters to be added to
330 * meet the minimum required mpdudensity.
332 * Caller should make sure that the rate is HT.
334 * TODO: is this delimiter calculation supposed to be the
335 * total frame length, the hdr length, the data length (including
336 * delimiters, padding, CRC, etc) or ?
338 * TODO: this should ensure that the rate control information
339 * HAS been setup for the first rate.
341 * TODO: ensure this is only called for MCS rates.
343 * TODO: enforce MCS < 31
346 ath_compute_num_delims(struct ath_softc *sc, struct ath_buf *first_bf,
349 const HAL_RATE_TABLE *rt = sc->sc_currates;
350 struct ieee80211_node *ni = first_bf->bf_node;
351 struct ieee80211vap *vap = ni->ni_vap;
352 int ndelim, mindelim = 0;
353 int mpdudensity; /* in 1/100'th of a microsecond */
354 uint8_t rc, rix, flags;
356 uint32_t nsymbits, nsymbols;
360 * vap->iv_ampdu_density is a value, rather than the actual
363 if (vap->iv_ampdu_density > IEEE80211_HTCAP_MPDUDENSITY_16)
364 mpdudensity = 1600; /* maximum density */
366 mpdudensity = ieee80211_mpdudensity_map[vap->iv_ampdu_density];
368 /* Select standard number of delimiters based on frame length */
369 ndelim = ATH_AGGR_GET_NDELIM(pktlen);
372 * If encryption is enabled, add extra delimiters to let the
373 * crypto hardware catch up. This could be tuned per-MAC and
374 * per-rate, but for now we'll simply assume encryption is
377 * Also note that the Atheros reference driver inserts two
378 * delimiters by default for pre-AR9380 peers. This will
379 * include "that" required delimiter.
381 ndelim += ATH_AGGR_ENCRYPTDELIM;
384 * For AR9380, there's a minimum number of delimeters
385 * required when doing RTS.
387 * XXX TODO: this is only needed if (a) RTS/CTS is enabled, and
388 * XXX (b) this is the first sub-frame in the aggregate.
390 if (sc->sc_use_ent && (sc->sc_ent_cfg & AH_ENT_RTSCTS_DELIM_WAR)
391 && ndelim < AH_FIRST_DESC_NDELIMS)
392 ndelim = AH_FIRST_DESC_NDELIMS;
395 * If sc_delim_min_pad is non-zero, enforce it as the minimum
396 * pad delimiter count.
398 if (sc->sc_delim_min_pad != 0)
399 ndelim = MAX(ndelim, sc->sc_delim_min_pad);
401 DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
402 "%s: pktlen=%d, ndelim=%d, mpdudensity=%d\n",
403 __func__, pktlen, ndelim, mpdudensity);
406 * If the MPDU density is 0, we can return here.
407 * Otherwise, we need to convert the desired mpdudensity
408 * into a byte length, based on the rate in the subframe.
410 if (mpdudensity == 0)
414 * Convert desired mpdu density from microeconds to bytes based
415 * on highest rate in rate series (i.e. first rate) to determine
416 * required minimum length for subframe. Take into account
417 * whether high rate is 20 or 40Mhz and half or full GI.
419 rix = first_bf->bf_state.bfs_rc[0].rix;
420 rc = rt->info[rix].rateCode;
421 flags = first_bf->bf_state.bfs_rc[0].flags;
422 width = !! (flags & ATH_RC_CW40_FLAG);
423 half_gi = !! (flags & ATH_RC_SGI_FLAG);
426 * mpdudensity is in 1/100th of a usec, so divide by 100
429 nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(mpdudensity);
431 nsymbols = NUM_SYMBOLS_PER_USEC(mpdudensity);
437 nsymbits = bits_per_symbol[HT_RC_2_MCS(rc)][width];
438 minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
441 * Min length is the minimum frame length for the
442 * required MPDU density.
444 if (pktlen < minlen) {
445 mindelim = (minlen - pktlen) / ATH_AGGR_DELIM_SZ;
446 ndelim = MAX(mindelim, ndelim);
449 DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR,
450 "%s: pktlen=%d, minlen=%d, rix=%x, rc=%x, width=%d, hgi=%d, ndelim=%d\n",
451 __func__, pktlen, minlen, rix, rc, width, half_gi, ndelim);
457 * Fetch the aggregation limit.
459 * It's the lowest of the four rate series 4ms frame length.
462 ath_get_aggr_limit(struct ath_softc *sc, struct ath_buf *bf)
464 int amin = ATH_AGGR_MAXSIZE;
467 if (sc->sc_aggr_limit > 0 && sc->sc_aggr_limit < ATH_AGGR_MAXSIZE)
468 amin = sc->sc_aggr_limit;
470 for (i = 0; i < ATH_RC_NUM; i++) {
471 if (bf->bf_state.bfs_rc[i].tries == 0)
473 amin = MIN(amin, bf->bf_state.bfs_rc[i].max4msframelen);
476 DPRINTF(sc, ATH_DEBUG_SW_TX_AGGR, "%s: max frame len= %d\n",
483 * Setup a 11n rate series structure
485 * This should be called for both legacy and MCS rates.
487 * This uses the rate series stuf from ath_tx_rate_fill_rcflags().
489 * It, along with ath_buf_set_rate, must be called -after- a burst
490 * or aggregate is setup.
493 ath_rateseries_setup(struct ath_softc *sc, struct ieee80211_node *ni,
494 struct ath_buf *bf, HAL_11N_RATE_SERIES *series)
496 struct ieee80211com *ic = ni->ni_ic;
497 struct ath_hal *ah = sc->sc_ah;
498 HAL_BOOL shortPreamble = AH_FALSE;
499 const HAL_RATE_TABLE *rt = sc->sc_currates;
502 struct ath_rc_series *rc = bf->bf_state.bfs_rc;
504 if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
505 (ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE))
506 shortPreamble = AH_TRUE;
509 * If this is the first frame in an aggregate series,
510 * use the aggregate length.
512 if (bf->bf_state.bfs_aggr)
513 pktlen = bf->bf_state.bfs_al;
515 pktlen = bf->bf_state.bfs_pktlen;
518 * XXX TODO: modify this routine to use the bfs_rc[x].flags
521 memset(series, 0, sizeof(HAL_11N_RATE_SERIES) * 4);
522 for (i = 0; i < ATH_RC_NUM; i++) {
523 /* Only set flags for actual TX attempts */
524 if (rc[i].tries == 0)
527 series[i].Tries = rc[i].tries;
530 * XXX TODO: When the NIC is capable of three stream TX,
531 * transmit 1/2 stream rates on two streams.
533 * This reduces the power consumption of the NIC and
534 * keeps it within the PCIe slot power limits.
536 series[i].ChSel = sc->sc_cur_txchainmask;
539 * Setup rate and TX power cap for this series.
541 series[i].Rate = rt->info[rc[i].rix].rateCode;
542 series[i].RateIndex = rc[i].rix;
543 series[i].tx_power_cap = rc[i].tx_power_cap;
546 * Enable RTS/CTS as appropriate.
548 if (rc[i].flags & ATH_RC_RTSCTS_FLAG)
549 series[i].RateFlags |= HAL_RATESERIES_RTS_CTS;
552 * 11n rate? Update 11n flags.
554 if (rc[i].flags & ATH_RC_HT_FLAG) {
555 if (rc[i].flags & ATH_RC_CW40_FLAG)
556 series[i].RateFlags |= HAL_RATESERIES_2040;
558 if (rc[i].flags & ATH_RC_SGI_FLAG)
559 series[i].RateFlags |= HAL_RATESERIES_HALFGI;
561 if (rc[i].flags & ATH_RC_STBC_FLAG)
562 series[i].RateFlags |= HAL_RATESERIES_STBC;
566 * PktDuration doesn't include slot, ACK, RTS, etc timing -
567 * it's just the packet duration
569 if (rc[i].flags & ATH_RC_HT_FLAG) {
570 series[i].PktDuration =
571 ath_computedur_ht(pktlen
573 , HT_RC_2_STREAMS(series[i].Rate)
574 , series[i].RateFlags & HAL_RATESERIES_2040
575 , series[i].RateFlags & HAL_RATESERIES_HALFGI);
579 rt->info[rc[i].rix].shortPreamble;
580 series[i].PktDuration = ath_hal_computetxtime(ah,
581 rt, pktlen, rc[i].rix, shortPreamble);
588 ath_rateseries_print(struct ath_softc *sc, HAL_11N_RATE_SERIES *series)
591 for (i = 0; i < ATH_RC_NUM; i++) {
592 device_printf(sc->sc_dev ,"series %d: rate %x; tries %d; "
593 "pktDuration %d; chSel %d; txpowcap %d, rateFlags %x\n",
597 series[i].PktDuration,
599 series[i].tx_power_cap,
600 series[i].RateFlags);
606 * Setup the 11n rate scenario and burst duration for the given TX descriptor
609 * This isn't useful for sending beacon frames, which has different needs
610 * wrt what's passed into the rate scenario function.
613 ath_buf_set_rate(struct ath_softc *sc, struct ieee80211_node *ni,
616 HAL_11N_RATE_SERIES series[4];
617 struct ath_desc *ds = bf->bf_desc;
618 struct ath_hal *ah = sc->sc_ah;
619 int is_pspoll = (bf->bf_state.bfs_atype == HAL_PKT_TYPE_PSPOLL);
620 int ctsrate = bf->bf_state.bfs_ctsrate;
621 int flags = bf->bf_state.bfs_txflags;
623 /* Setup rate scenario */
624 memset(&series, 0, sizeof(series));
626 ath_rateseries_setup(sc, ni, bf, series);
629 ath_rateseries_print(sc, series);
632 /* Set rate scenario */
634 * Note: Don't allow hardware to override the duration on
637 ath_hal_set11nratescenario(ah, ds,
638 !is_pspoll, /* whether to override the duration or not */
639 ctsrate, /* rts/cts rate */
640 series, /* 11n rate series */
641 4, /* number of series */
644 /* Set burst duration */
646 * This is only required when doing 11n burst, not aggregation
647 * ie, if there's a second frame in a RIFS or A-MPDU burst
648 * w/ >1 A-MPDU frame bursting back to back.
649 * Normal A-MPDU doesn't do bursting -between- aggregates.
651 * .. and it's highly likely this won't ever be implemented
653 //ath_hal_set11nburstduration(ah, ds, 8192);
657 * Form an aggregate packet list.
659 * This function enforces the aggregate restrictions/requirements.
663 * + The aggregate size maximum (64k for AR9160 and later, 8K for
664 * AR5416 when doing RTS frame protection.)
665 * + Maximum number of sub-frames for an aggregate
666 * + The aggregate delimiter size, giving MACs time to do whatever is
667 * needed before each frame
668 * + Enforce the BAW limit
670 * Each descriptor queued should have the DMA setup.
671 * The rate series, descriptor setup, linking, etc is all done
672 * externally. This routine simply chains them together.
673 * ath_tx_setds_11n() will take care of configuring the per-
674 * descriptor setup, and ath_buf_set_rate() will configure the
677 * The TID lock is required for the entirety of this function.
679 * If some code in another thread adds to the head of this
680 * list, very strange behaviour will occur. Since retransmission is the
681 * only reason this will occur, and this routine is designed to be called
682 * from within the scheduler task, it won't ever clash with the completion
685 * So if you want to call this from an upper layer context (eg, to direct-
686 * dispatch aggregate frames to the hardware), please keep this in mind.
689 ath_tx_form_aggr(struct ath_softc *sc, struct ath_node *an,
690 struct ath_tid *tid, ath_bufhead *bf_q)
692 //struct ieee80211_node *ni = &an->an_node;
693 struct ath_buf *bf, *bf_first = NULL, *bf_prev = NULL;
695 uint16_t aggr_limit = 0, al = 0, bpad = 0, al_delta, h_baw;
696 struct ieee80211_tx_ampdu *tap;
697 int status = ATH_AGGR_DONE;
698 int prev_frames = 0; /* XXX for AR5416 burst, not done here */
699 int prev_al = 0; /* XXX also for AR5416 burst */
701 ATH_TX_LOCK_ASSERT(sc);
703 tap = ath_tx_get_tx_tid(an, tid->tid);
705 status = ATH_AGGR_ERROR;
709 h_baw = tap->txa_wnd / 2;
712 bf = ATH_TID_FIRST(tid);
713 if (bf_first == NULL)
716 status = ATH_AGGR_DONE;
720 * It's the first frame;
721 * set the aggregation limit based on the
722 * rate control decision that has been made.
724 aggr_limit = ath_get_aggr_limit(sc, bf_first);
727 /* Set this early just so things don't get confused */
731 * If the frame doesn't have a sequence number that we're
732 * tracking in the BAW (eg NULL QOS data frame), we can't
733 * aggregate it. Stop the aggregation process; the sender
734 * can then TX what's in the list thus far and then
735 * TX the frame individually.
737 if (! bf->bf_state.bfs_dobaw) {
738 status = ATH_AGGR_NONAGGR;
743 * If any of the rates are non-HT, this packet
744 * can't be aggregated.
745 * XXX TODO: add a bf_state flag which gets marked
746 * if any active rate is non-HT.
750 * do not exceed aggregation limit
752 al_delta = ATH_AGGR_DELIM_SZ + bf->bf_state.bfs_pktlen;
754 (aggr_limit < (al + bpad + al_delta + prev_al))) {
755 status = ATH_AGGR_LIMITED;
760 * If RTS/CTS is set on the first frame, enforce
761 * the RTS aggregate limit.
763 if (bf_first->bf_state.bfs_txflags &
764 (HAL_TXDESC_CTSENA | HAL_TXDESC_RTSENA)) {
766 (sc->sc_rts_aggr_limit <
767 (al + bpad + al_delta + prev_al))) {
768 status = ATH_AGGR_8K_LIMITED;
774 * Do not exceed subframe limit.
776 if ((nframes + prev_frames) >= MIN((h_baw),
777 IEEE80211_AMPDU_SUBFRAME_DEFAULT)) {
778 status = ATH_AGGR_LIMITED;
783 * If the current frame has an RTS/CTS configuration
784 * that differs from the first frame, override the
785 * subsequent frame with this config.
787 if (bf != bf_first) {
788 bf->bf_state.bfs_txflags &=
789 ~ (HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA);
790 bf->bf_state.bfs_txflags |=
791 bf_first->bf_state.bfs_txflags &
792 (HAL_TXDESC_RTSENA | HAL_TXDESC_CTSENA);
796 * If the packet has a sequence number, do not
797 * step outside of the block-ack window.
799 if (! BAW_WITHIN(tap->txa_start, tap->txa_wnd,
800 SEQNO(bf->bf_state.bfs_seqno))) {
801 status = ATH_AGGR_BAW_CLOSED;
806 * this packet is part of an aggregate.
808 ATH_TID_REMOVE(tid, bf, bf_list);
810 /* The TID lock is required for the BAW update */
811 ath_tx_addto_baw(sc, an, tid, bf);
812 bf->bf_state.bfs_addedbaw = 1;
815 * XXX enforce ACK for aggregate frames (this needs to be
816 * XXX handled more gracefully?
818 if (bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) {
819 device_printf(sc->sc_dev,
820 "%s: HAL_TXDESC_NOACK set for an aggregate frame?\n",
822 bf->bf_state.bfs_txflags &= (~HAL_TXDESC_NOACK);
826 * Add the now owned buffer (which isn't
827 * on the software TXQ any longer) to our
828 * aggregate frame list.
830 TAILQ_INSERT_TAIL(bf_q, bf, bf_list);
833 /* Completion handler */
834 bf->bf_comp = ath_tx_aggr_comp;
837 * add padding for previous frame to aggregation length
839 al += bpad + al_delta;
842 * Calculate delimiters needed for the current frame
844 bf->bf_state.bfs_ndelim =
845 ath_compute_num_delims(sc, bf_first,
846 bf->bf_state.bfs_pktlen);
849 * Calculate the padding needed from this set of delimiters,
850 * used when calculating if the next frame will fit in
853 bpad = PADBYTES(al_delta) + (bf->bf_state.bfs_ndelim << 2);
856 * Chain the buffers together
859 bf_prev->bf_next = bf;
863 * If we're leaking frames, just return at this point;
864 * we've queued a single frame and we don't want to add
867 if (tid->an->an_leak_count) {
868 status = ATH_AGGR_LEAK_CLOSED;
874 * terminate aggregation on a small packet boundary
876 if (bf->bf_state.bfs_pktlen < ATH_AGGR_MINPLEN) {
877 status = ATH_AGGR_SHORTPKT;
886 * Just in case the list was empty when we tried to
887 * dequeue a packet ..
890 bf_first->bf_state.bfs_al = al;
891 bf_first->bf_state.bfs_nframes = nframes;