1 /*
2  * Copyright (c) 2010 Broadcom Corporation
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
11  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
13  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
14  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 #include <net/mac80211.h>
17 
18 #include "rate.h"
19 #include "scb.h"
20 #include "phy/phy_hal.h"
21 #include "antsel.h"
22 #include "main.h"
23 #include "ampdu.h"
24 #include "debug.h"
25 #include "brcms_trace_events.h"
26 
27 /* max number of mpdus in an ampdu */
28 #define AMPDU_MAX_MPDU			32
29 /* max number of mpdus in an ampdu to a legacy */
30 #define AMPDU_NUM_MPDU_LEGACY		16
31 /* max Tx ba window size (in pdu) */
32 #define AMPDU_TX_BA_MAX_WSIZE		64
33 /* default Tx ba window size (in pdu) */
34 #define AMPDU_TX_BA_DEF_WSIZE		64
35 /* default Rx ba window size (in pdu) */
36 #define AMPDU_RX_BA_DEF_WSIZE		64
37 /* max Rx ba window size (in pdu) */
38 #define AMPDU_RX_BA_MAX_WSIZE		64
39 /* max dur of tx ampdu (in msec) */
40 #define	AMPDU_MAX_DUR			5
41 /* default tx retry limit */
42 #define AMPDU_DEF_RETRY_LIMIT		5
43 /* default tx retry limit at reg rate */
44 #define AMPDU_DEF_RR_RETRY_LIMIT	2
45 /* default ffpld reserved bytes */
46 #define AMPDU_DEF_FFPLD_RSVD		2048
47 /* # of inis to be freed on detach */
48 #define AMPDU_INI_FREE			10
49 /* max # of mpdus released at a time */
50 #define	AMPDU_SCB_MAX_RELEASE		20
51 
52 #define NUM_FFPLD_FIFO 4	/* number of fifo concerned by pre-loading */
53 #define FFPLD_TX_MAX_UNFL   200	/* default value of the average number of ampdu
54 				 * without underflows
55 				 */
56 #define FFPLD_MPDU_SIZE 1800	/* estimate of maximum mpdu size */
57 #define FFPLD_MAX_MCS 23	/* we don't deal with mcs 32 */
58 #define FFPLD_PLD_INCR 1000	/* increments in bytes */
59 #define FFPLD_MAX_AMPDU_CNT 5000	/* maximum number of ampdu we
60 					 * accumulate between resets.
61 					 */
62 
63 #define AMPDU_DELIMITER_LEN	4
64 
65 /* max allowed number of mpdus in an ampdu (2 streams) */
66 #define AMPDU_NUM_MPDU		16
67 
68 #define TX_SEQ_TO_INDEX(seq) ((seq) % AMPDU_TX_BA_MAX_WSIZE)
69 
70 /* max possible overhead per mpdu in the ampdu; 3 is for roundup if needed */
71 #define AMPDU_MAX_MPDU_OVERHEAD (FCS_LEN + DOT11_ICV_AES_LEN +\
72 	AMPDU_DELIMITER_LEN + 3\
73 	+ DOT11_A4_HDR_LEN + DOT11_QOS_LEN + DOT11_IV_MAX_LEN)
74 
75 /* modulo add/sub, bound = 2^k */
76 #define MODADD_POW2(x, y, bound) (((x) + (y)) & ((bound) - 1))
77 #define MODSUB_POW2(x, y, bound) (((x) - (y)) & ((bound) - 1))
78 
79 /* structure to hold tx fifo information and pre-loading state
80  * counters specific to tx underflows of ampdus
81  * some counters might be redundant with the ones in wlc or ampdu structures.
82  * This allows to maintain a specific state independently of
83  * how often and/or when the wlc counters are updated.
84  *
85  * ampdu_pld_size: number of bytes to be pre-loaded
86  * mcs2ampdu_table: per-mcs max # of mpdus in an ampdu
87  * prev_txfunfl: num of underflows last read from the HW macstats counter
88  * accum_txfunfl: num of underflows since we modified pld params
89  * accum_txampdu: num of tx ampdu since we modified pld params
90  * prev_txampdu: previous reading of tx ampdu
91  * dmaxferrate: estimated dma avg xfer rate in kbits/sec
92  */
93 struct brcms_fifo_info {
94 	u16 ampdu_pld_size;
95 	u8 mcs2ampdu_table[FFPLD_MAX_MCS + 1];
96 	u16 prev_txfunfl;
97 	u32 accum_txfunfl;
98 	u32 accum_txampdu;
99 	u32 prev_txampdu;
100 	u32 dmaxferrate;
101 };
102 
103 /* AMPDU module specific state
104  *
105  * wlc: pointer to main wlc structure
106  * scb_handle: scb cubby handle to retrieve data from scb
107  * ini_enable: per-tid initiator enable/disable of ampdu
108  * ba_tx_wsize: Tx ba window size (in pdu)
109  * ba_rx_wsize: Rx ba window size (in pdu)
110  * retry_limit: mpdu transmit retry limit
111  * rr_retry_limit: mpdu transmit retry limit at regular rate
112  * retry_limit_tid: per-tid mpdu transmit retry limit
113  * rr_retry_limit_tid: per-tid mpdu transmit retry limit at regular rate
114  * mpdu_density: min mpdu spacing (0-7) ==> 2^(x-1)/8 usec
115  * max_pdu: max pdus allowed in ampdu
116  * dur: max duration of an ampdu (in msec)
117  * rx_factor: maximum rx ampdu factor (0-3) ==> 2^(13+x) bytes
118  * ffpld_rsvd: number of bytes to reserve for preload
119  * max_txlen: max size of ampdu per mcs, bw and sgi
120  * mfbr: enable multiple fallback rate
121  * tx_max_funl: underflows should be kept such that
122  *		(tx_max_funfl*underflows) < tx frames
123  * fifo_tb: table of fifo infos
124  */
125 struct ampdu_info {
126 	struct brcms_c_info *wlc;
127 	int scb_handle;
128 	u8 ini_enable[AMPDU_MAX_SCB_TID];
129 	u8 ba_tx_wsize;
130 	u8 ba_rx_wsize;
131 	u8 retry_limit;
132 	u8 rr_retry_limit;
133 	u8 retry_limit_tid[AMPDU_MAX_SCB_TID];
134 	u8 rr_retry_limit_tid[AMPDU_MAX_SCB_TID];
135 	u8 mpdu_density;
136 	s8 max_pdu;
137 	u8 dur;
138 	u8 rx_factor;
139 	u32 ffpld_rsvd;
140 	u32 max_txlen[MCS_TABLE_SIZE][2][2];
141 	bool mfbr;
142 	u32 tx_max_funl;
143 	struct brcms_fifo_info fifo_tb[NUM_FFPLD_FIFO];
144 };
145 
146 /* used for flushing ampdu packets */
147 struct cb_del_ampdu_pars {
148 	struct ieee80211_sta *sta;
149 	u16 tid;
150 };
151 
152 static void brcms_c_scb_ampdu_update_max_txlen(struct ampdu_info *ampdu, u8 dur)
153 {
154 	u32 rate, mcs;
155 
156 	for (mcs = 0; mcs < MCS_TABLE_SIZE; mcs++) {
157 		/* rate is in Kbps; dur is in msec ==> len = (rate * dur) / 8 */
158 		/* 20MHz, No SGI */
159 		rate = mcs_2_rate(mcs, false, false);
160 		ampdu->max_txlen[mcs][0][0] = (rate * dur) >> 3;
161 		/* 40 MHz, No SGI */
162 		rate = mcs_2_rate(mcs, true, false);
163 		ampdu->max_txlen[mcs][1][0] = (rate * dur) >> 3;
164 		/* 20MHz, SGI */
165 		rate = mcs_2_rate(mcs, false, true);
166 		ampdu->max_txlen[mcs][0][1] = (rate * dur) >> 3;
167 		/* 40 MHz, SGI */
168 		rate = mcs_2_rate(mcs, true, true);
169 		ampdu->max_txlen[mcs][1][1] = (rate * dur) >> 3;
170 	}
171 }
172 
173 static bool brcms_c_ampdu_cap(struct ampdu_info *ampdu)
174 {
175 	if (BRCMS_PHY_11N_CAP(ampdu->wlc->band))
176 		return true;
177 	else
178 		return false;
179 }
180 
181 static int brcms_c_ampdu_set(struct ampdu_info *ampdu, bool on)
182 {
183 	struct brcms_c_info *wlc = ampdu->wlc;
184 	struct bcma_device *core = wlc->hw->d11core;
185 
186 	wlc->pub->_ampdu = false;
187 
188 	if (on) {
189 		if (!(wlc->pub->_n_enab & SUPPORT_11N)) {
190 			brcms_err(core, "wl%d: driver not nmode enabled\n",
191 				  wlc->pub->unit);
192 			return -ENOTSUPP;
193 		}
194 		if (!brcms_c_ampdu_cap(ampdu)) {
195 			brcms_err(core, "wl%d: device not ampdu capable\n",
196 				  wlc->pub->unit);
197 			return -ENOTSUPP;
198 		}
199 		wlc->pub->_ampdu = on;
200 	}
201 
202 	return 0;
203 }
204 
205 static void brcms_c_ffpld_init(struct ampdu_info *ampdu)
206 {
207 	int i, j;
208 	struct brcms_fifo_info *fifo;
209 
210 	for (j = 0; j < NUM_FFPLD_FIFO; j++) {
211 		fifo = (ampdu->fifo_tb + j);
212 		fifo->ampdu_pld_size = 0;
213 		for (i = 0; i <= FFPLD_MAX_MCS; i++)
214 			fifo->mcs2ampdu_table[i] = 255;
215 		fifo->dmaxferrate = 0;
216 		fifo->accum_txampdu = 0;
217 		fifo->prev_txfunfl = 0;
218 		fifo->accum_txfunfl = 0;
219 
220 	}
221 }
222 
223 struct ampdu_info *brcms_c_ampdu_attach(struct brcms_c_info *wlc)
224 {
225 	struct ampdu_info *ampdu;
226 	int i;
227 
228 	ampdu = kzalloc(sizeof(struct ampdu_info), GFP_ATOMIC);
229 	if (!ampdu)
230 		return NULL;
231 
232 	ampdu->wlc = wlc;
233 
234 	for (i = 0; i < AMPDU_MAX_SCB_TID; i++)
235 		ampdu->ini_enable[i] = true;
236 	/* Disable ampdu for VO by default */
237 	ampdu->ini_enable[PRIO_8021D_VO] = false;
238 	ampdu->ini_enable[PRIO_8021D_NC] = false;
239 
240 	/* Disable ampdu for BK by default since not enough fifo space */
241 	ampdu->ini_enable[PRIO_8021D_NONE] = false;
242 	ampdu->ini_enable[PRIO_8021D_BK] = false;
243 
244 	ampdu->ba_tx_wsize = AMPDU_TX_BA_DEF_WSIZE;
245 	ampdu->ba_rx_wsize = AMPDU_RX_BA_DEF_WSIZE;
246 	ampdu->mpdu_density = AMPDU_DEF_MPDU_DENSITY;
247 	ampdu->max_pdu = AUTO;
248 	ampdu->dur = AMPDU_MAX_DUR;
249 
250 	ampdu->ffpld_rsvd = AMPDU_DEF_FFPLD_RSVD;
251 	/*
252 	 * bump max ampdu rcv size to 64k for all 11n
253 	 * devices except 4321A0 and 4321A1
254 	 */
255 	if (BRCMS_ISNPHY(wlc->band) && NREV_LT(wlc->band->phyrev, 2))
256 		ampdu->rx_factor = IEEE80211_HT_MAX_AMPDU_32K;
257 	else
258 		ampdu->rx_factor = IEEE80211_HT_MAX_AMPDU_64K;
259 	ampdu->retry_limit = AMPDU_DEF_RETRY_LIMIT;
260 	ampdu->rr_retry_limit = AMPDU_DEF_RR_RETRY_LIMIT;
261 
262 	for (i = 0; i < AMPDU_MAX_SCB_TID; i++) {
263 		ampdu->retry_limit_tid[i] = ampdu->retry_limit;
264 		ampdu->rr_retry_limit_tid[i] = ampdu->rr_retry_limit;
265 	}
266 
267 	brcms_c_scb_ampdu_update_max_txlen(ampdu, ampdu->dur);
268 	ampdu->mfbr = false;
269 	/* try to set ampdu to the default value */
270 	brcms_c_ampdu_set(ampdu, wlc->pub->_ampdu);
271 
272 	ampdu->tx_max_funl = FFPLD_TX_MAX_UNFL;
273 	brcms_c_ffpld_init(ampdu);
274 
275 	return ampdu;
276 }
277 
278 void brcms_c_ampdu_detach(struct ampdu_info *ampdu)
279 {
280 	kfree(ampdu);
281 }
282 
283 static void brcms_c_scb_ampdu_update_config(struct ampdu_info *ampdu,
284 					    struct scb *scb)
285 {
286 	struct scb_ampdu *scb_ampdu = &scb->scb_ampdu;
287 	int i;
288 
289 	scb_ampdu->max_pdu = AMPDU_NUM_MPDU;
290 
291 	/* go back to legacy size if some preloading is occurring */
292 	for (i = 0; i < NUM_FFPLD_FIFO; i++) {
293 		if (ampdu->fifo_tb[i].ampdu_pld_size > FFPLD_PLD_INCR)
294 			scb_ampdu->max_pdu = AMPDU_NUM_MPDU_LEGACY;
295 	}
296 
297 	/* apply user override */
298 	if (ampdu->max_pdu != AUTO)
299 		scb_ampdu->max_pdu = (u8) ampdu->max_pdu;
300 
301 	scb_ampdu->release = min_t(u8, scb_ampdu->max_pdu,
302 				   AMPDU_SCB_MAX_RELEASE);
303 
304 	if (scb_ampdu->max_rx_ampdu_bytes)
305 		scb_ampdu->release = min_t(u8, scb_ampdu->release,
306 			scb_ampdu->max_rx_ampdu_bytes / 1600);
307 
308 	scb_ampdu->release = min(scb_ampdu->release,
309 				 ampdu->fifo_tb[TX_AC_BE_FIFO].
310 				 mcs2ampdu_table[FFPLD_MAX_MCS]);
311 }
312 
313 static void brcms_c_scb_ampdu_update_config_all(struct ampdu_info *ampdu)
314 {
315 	brcms_c_scb_ampdu_update_config(ampdu, &ampdu->wlc->pri_scb);
316 }
317 
318 static void brcms_c_ffpld_calc_mcs2ampdu_table(struct ampdu_info *ampdu, int f)
319 {
320 	int i;
321 	u32 phy_rate, dma_rate, tmp;
322 	u8 max_mpdu;
323 	struct brcms_fifo_info *fifo = (ampdu->fifo_tb + f);
324 
325 	/* recompute the dma rate */
326 	/* note : we divide/multiply by 100 to avoid integer overflows */
327 	max_mpdu = min_t(u8, fifo->mcs2ampdu_table[FFPLD_MAX_MCS],
328 			 AMPDU_NUM_MPDU_LEGACY);
329 	phy_rate = mcs_2_rate(FFPLD_MAX_MCS, true, false);
330 	dma_rate =
331 	    (((phy_rate / 100) *
332 	      (max_mpdu * FFPLD_MPDU_SIZE - fifo->ampdu_pld_size))
333 	     / (max_mpdu * FFPLD_MPDU_SIZE)) * 100;
334 	fifo->dmaxferrate = dma_rate;
335 
336 	/* fill up the mcs2ampdu table; do not recalc the last mcs */
337 	dma_rate = dma_rate >> 7;
338 	for (i = 0; i < FFPLD_MAX_MCS; i++) {
339 		/* shifting to keep it within integer range */
340 		phy_rate = mcs_2_rate(i, true, false) >> 7;
341 		if (phy_rate > dma_rate) {
342 			tmp = ((fifo->ampdu_pld_size * phy_rate) /
343 			       ((phy_rate - dma_rate) * FFPLD_MPDU_SIZE)) + 1;
344 			tmp = min_t(u32, tmp, 255);
345 			fifo->mcs2ampdu_table[i] = (u8) tmp;
346 		}
347 	}
348 }
349 
350 /* evaluate the dma transfer rate using the tx underflows as feedback.
351  * If necessary, increase tx fifo preloading. If not enough,
352  * decrease maximum ampdu size for each mcs till underflows stop
353  * Return 1 if pre-loading not active, -1 if not an underflow event,
354  * 0 if pre-loading module took care of the event.
355  */
356 static int brcms_c_ffpld_check_txfunfl(struct brcms_c_info *wlc, int fid)
357 {
358 	struct ampdu_info *ampdu = wlc->ampdu;
359 	u32 phy_rate = mcs_2_rate(FFPLD_MAX_MCS, true, false);
360 	u32 txunfl_ratio;
361 	u8 max_mpdu;
362 	u32 current_ampdu_cnt = 0;
363 	u16 max_pld_size;
364 	u32 new_txunfl;
365 	struct brcms_fifo_info *fifo = (ampdu->fifo_tb + fid);
366 	uint xmtfifo_sz;
367 	u16 cur_txunfl;
368 
369 	/* return if we got here for a different reason than underflows */
370 	cur_txunfl = brcms_b_read_shm(wlc->hw,
371 				      M_UCODE_MACSTAT +
372 				      offsetof(struct macstat, txfunfl[fid]));
373 	new_txunfl = (u16) (cur_txunfl - fifo->prev_txfunfl);
374 	if (new_txunfl == 0) {
375 		brcms_dbg_ht(wlc->hw->d11core,
376 			     "TX status FRAG set but no tx underflows\n");
377 		return -1;
378 	}
379 	fifo->prev_txfunfl = cur_txunfl;
380 
381 	if (!ampdu->tx_max_funl)
382 		return 1;
383 
384 	/* check if fifo is big enough */
385 	if (brcms_b_xmtfifo_sz_get(wlc->hw, fid, &xmtfifo_sz))
386 		return -1;
387 
388 	if ((TXFIFO_SIZE_UNIT * (u32) xmtfifo_sz) <= ampdu->ffpld_rsvd)
389 		return 1;
390 
391 	max_pld_size = TXFIFO_SIZE_UNIT * xmtfifo_sz - ampdu->ffpld_rsvd;
392 	fifo->accum_txfunfl += new_txunfl;
393 
394 	/* we need to wait for at least 10 underflows */
395 	if (fifo->accum_txfunfl < 10)
396 		return 0;
397 
398 	brcms_dbg_ht(wlc->hw->d11core, "ampdu_count %d  tx_underflows %d\n",
399 		     current_ampdu_cnt, fifo->accum_txfunfl);
400 
401 	/*
402 	   compute the current ratio of tx unfl per ampdu.
403 	   When the current ampdu count becomes too
404 	   big while the ratio remains small, we reset
405 	   the current count in order to not
406 	   introduce too big of a latency in detecting a
407 	   large amount of tx underflows later.
408 	 */
409 
410 	txunfl_ratio = current_ampdu_cnt / fifo->accum_txfunfl;
411 
412 	if (txunfl_ratio > ampdu->tx_max_funl) {
413 		if (current_ampdu_cnt >= FFPLD_MAX_AMPDU_CNT)
414 			fifo->accum_txfunfl = 0;
415 
416 		return 0;
417 	}
418 	max_mpdu = min_t(u8, fifo->mcs2ampdu_table[FFPLD_MAX_MCS],
419 			 AMPDU_NUM_MPDU_LEGACY);
420 
421 	/* In case max value max_pdu is already lower than
422 	   the fifo depth, there is nothing more we can do.
423 	 */
424 
425 	if (fifo->ampdu_pld_size >= max_mpdu * FFPLD_MPDU_SIZE) {
426 		fifo->accum_txfunfl = 0;
427 		return 0;
428 	}
429 
430 	if (fifo->ampdu_pld_size < max_pld_size) {
431 
432 		/* increment by TX_FIFO_PLD_INC bytes */
433 		fifo->ampdu_pld_size += FFPLD_PLD_INCR;
434 		if (fifo->ampdu_pld_size > max_pld_size)
435 			fifo->ampdu_pld_size = max_pld_size;
436 
437 		/* update scb release size */
438 		brcms_c_scb_ampdu_update_config_all(ampdu);
439 
440 		/*
441 		 * compute a new dma xfer rate for max_mpdu @ max mcs.
442 		 * This is the minimum dma rate that can achieve no
443 		 * underflow condition for the current mpdu size.
444 		 *
445 		 * note : we divide/multiply by 100 to avoid integer overflows
446 		 */
447 		fifo->dmaxferrate =
448 		    (((phy_rate / 100) *
449 		      (max_mpdu * FFPLD_MPDU_SIZE - fifo->ampdu_pld_size))
450 		     / (max_mpdu * FFPLD_MPDU_SIZE)) * 100;
451 
452 		brcms_dbg_ht(wlc->hw->d11core,
453 			     "DMA estimated transfer rate %d; "
454 			     "pre-load size %d\n",
455 			     fifo->dmaxferrate, fifo->ampdu_pld_size);
456 	} else {
457 
458 		/* decrease ampdu size */
459 		if (fifo->mcs2ampdu_table[FFPLD_MAX_MCS] > 1) {
460 			if (fifo->mcs2ampdu_table[FFPLD_MAX_MCS] == 255)
461 				fifo->mcs2ampdu_table[FFPLD_MAX_MCS] =
462 				    AMPDU_NUM_MPDU_LEGACY - 1;
463 			else
464 				fifo->mcs2ampdu_table[FFPLD_MAX_MCS] -= 1;
465 
466 			/* recompute the table */
467 			brcms_c_ffpld_calc_mcs2ampdu_table(ampdu, fid);
468 
469 			/* update scb release size */
470 			brcms_c_scb_ampdu_update_config_all(ampdu);
471 		}
472 	}
473 	fifo->accum_txfunfl = 0;
474 	return 0;
475 }
476 
477 void
478 brcms_c_ampdu_tx_operational(struct brcms_c_info *wlc, u8 tid,
479 	u8 ba_wsize,		/* negotiated ba window size (in pdu) */
480 	uint max_rx_ampdu_bytes) /* from ht_cap in beacon */
481 {
482 	struct scb_ampdu *scb_ampdu;
483 	struct scb_ampdu_tid_ini *ini;
484 	struct ampdu_info *ampdu = wlc->ampdu;
485 	struct scb *scb = &wlc->pri_scb;
486 	scb_ampdu = &scb->scb_ampdu;
487 
488 	if (!ampdu->ini_enable[tid]) {
489 		brcms_err(wlc->hw->d11core, "%s: Rejecting tid %d\n",
490 			  __func__, tid);
491 		return;
492 	}
493 
494 	ini = &scb_ampdu->ini[tid];
495 	ini->tid = tid;
496 	ini->scb = scb_ampdu->scb;
497 	ini->ba_wsize = ba_wsize;
498 	scb_ampdu->max_rx_ampdu_bytes = max_rx_ampdu_bytes;
499 }
500 
501 void brcms_c_ampdu_reset_session(struct brcms_ampdu_session *session,
502 				 struct brcms_c_info *wlc)
503 {
504 	session->wlc = wlc;
505 	skb_queue_head_init(&session->skb_list);
506 	session->max_ampdu_len = 0;    /* determined from first MPDU */
507 	session->max_ampdu_frames = 0; /* determined from first MPDU */
508 	session->ampdu_len = 0;
509 	session->dma_len = 0;
510 }
511 
512 /*
513  * Preps the given packet for AMPDU based on the session data. If the
514  * frame cannot be accomodated in the current session, -ENOSPC is
515  * returned.
516  */
517 int brcms_c_ampdu_add_frame(struct brcms_ampdu_session *session,
518 			    struct sk_buff *p)
519 {
520 	struct brcms_c_info *wlc = session->wlc;
521 	struct ampdu_info *ampdu = wlc->ampdu;
522 	struct scb *scb = &wlc->pri_scb;
523 	struct scb_ampdu *scb_ampdu = &scb->scb_ampdu;
524 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(p);
525 	struct ieee80211_tx_rate *txrate = tx_info->status.rates;
526 	struct d11txh *txh = (struct d11txh *)p->data;
527 	unsigned ampdu_frames;
528 	u8 ndelim, tid;
529 	u8 *plcp;
530 	uint len;
531 	u16 mcl;
532 	bool fbr_iscck;
533 	bool rr;
534 
535 	ndelim = txh->RTSPLCPFallback[AMPDU_FBR_NULL_DELIM];
536 	plcp = (u8 *)(txh + 1);
537 	fbr_iscck = !(le16_to_cpu(txh->XtraFrameTypes) & 0x03);
538 	len = fbr_iscck ? BRCMS_GET_CCK_PLCP_LEN(txh->FragPLCPFallback) :
539 			  BRCMS_GET_MIMO_PLCP_LEN(txh->FragPLCPFallback);
540 	len = roundup(len, 4) + (ndelim + 1) * AMPDU_DELIMITER_LEN;
541 
542 	ampdu_frames = skb_queue_len(&session->skb_list);
543 	if (ampdu_frames != 0) {
544 		struct sk_buff *first;
545 
546 		if (ampdu_frames + 1 > session->max_ampdu_frames ||
547 		    session->ampdu_len + len > session->max_ampdu_len)
548 			return -ENOSPC;
549 
550 		/*
551 		 * We aren't really out of space if the new frame is of
552 		 * a different priority, but we want the same behaviour
553 		 * so return -ENOSPC anyway.
554 		 *
555 		 * XXX: The old AMPDU code did this, but is it really
556 		 * necessary?
557 		 */
558 		first = skb_peek(&session->skb_list);
559 		if (p->priority != first->priority)
560 			return -ENOSPC;
561 	}
562 
563 	/*
564 	 * Now that we're sure this frame can be accomodated, update the
565 	 * session information.
566 	 */
567 	session->ampdu_len += len;
568 	session->dma_len += p->len;
569 
570 	tid = (u8)p->priority;
571 
572 	/* Handle retry limits */
573 	if (txrate[0].count <= ampdu->rr_retry_limit_tid[tid]) {
574 		txrate[0].count++;
575 		rr = true;
576 	} else {
577 		txrate[1].count++;
578 		rr = false;
579 	}
580 
581 	if (ampdu_frames == 0) {
582 		u8 plcp0, plcp3, is40, sgi, mcs;
583 		uint fifo = le16_to_cpu(txh->TxFrameID) & TXFID_QUEUE_MASK;
584 		struct brcms_fifo_info *f = &ampdu->fifo_tb[fifo];
585 
586 		if (rr) {
587 			plcp0 = plcp[0];
588 			plcp3 = plcp[3];
589 		} else {
590 			plcp0 = txh->FragPLCPFallback[0];
591 			plcp3 = txh->FragPLCPFallback[3];
592 
593 		}
594 
595 		/* Limit AMPDU size based on MCS */
596 		is40 = (plcp0 & MIMO_PLCP_40MHZ) ? 1 : 0;
597 		sgi = plcp3_issgi(plcp3) ? 1 : 0;
598 		mcs = plcp0 & ~MIMO_PLCP_40MHZ;
599 		session->max_ampdu_len = min(scb_ampdu->max_rx_ampdu_bytes,
600 					     ampdu->max_txlen[mcs][is40][sgi]);
601 
602 		session->max_ampdu_frames = scb_ampdu->max_pdu;
603 		if (mcs_2_rate(mcs, true, false) >= f->dmaxferrate) {
604 			session->max_ampdu_frames =
605 				min_t(u16, f->mcs2ampdu_table[mcs],
606 				      session->max_ampdu_frames);
607 		}
608 	}
609 
610 	/*
611 	 * Treat all frames as "middle" frames of AMPDU here. First and
612 	 * last frames must be fixed up after all MPDUs have been prepped.
613 	 */
614 	mcl = le16_to_cpu(txh->MacTxControlLow);
615 	mcl &= ~TXC_AMPDU_MASK;
616 	mcl |= (TXC_AMPDU_MIDDLE << TXC_AMPDU_SHIFT);
617 	mcl &= ~(TXC_STARTMSDU | TXC_SENDRTS | TXC_SENDCTS);
618 	txh->MacTxControlLow = cpu_to_le16(mcl);
619 	txh->PreloadSize = 0;	/* always default to 0 */
620 
621 	skb_queue_tail(&session->skb_list, p);
622 
623 	return 0;
624 }
625 
626 void brcms_c_ampdu_finalize(struct brcms_ampdu_session *session)
627 {
628 	struct brcms_c_info *wlc = session->wlc;
629 	struct ampdu_info *ampdu = wlc->ampdu;
630 	struct sk_buff *first, *last;
631 	struct d11txh *txh;
632 	struct ieee80211_tx_info *tx_info;
633 	struct ieee80211_tx_rate *txrate;
634 	u8 ndelim;
635 	u8 *plcp;
636 	uint len;
637 	uint fifo;
638 	struct brcms_fifo_info *f;
639 	u16 mcl;
640 	bool fbr;
641 	bool fbr_iscck;
642 	struct ieee80211_rts *rts;
643 	bool use_rts = false, use_cts = false;
644 	u16 dma_len = session->dma_len;
645 	u16 mimo_ctlchbw = PHY_TXC1_BW_20MHZ;
646 	u32 rspec = 0, rspec_fallback = 0;
647 	u32 rts_rspec = 0, rts_rspec_fallback = 0;
648 	u8 plcp0, is40, mcs;
649 	u16 mch;
650 	u8 preamble_type = BRCMS_GF_PREAMBLE;
651 	u8 fbr_preamble_type = BRCMS_GF_PREAMBLE;
652 	u8 rts_preamble_type = BRCMS_LONG_PREAMBLE;
653 	u8 rts_fbr_preamble_type = BRCMS_LONG_PREAMBLE;
654 
655 	if (skb_queue_empty(&session->skb_list))
656 		return;
657 
658 	first = skb_peek(&session->skb_list);
659 	last = skb_peek_tail(&session->skb_list);
660 
661 	/* Need to fix up last MPDU first to adjust AMPDU length */
662 	txh = (struct d11txh *)last->data;
663 	fifo = le16_to_cpu(txh->TxFrameID) & TXFID_QUEUE_MASK;
664 	f = &ampdu->fifo_tb[fifo];
665 
666 	mcl = le16_to_cpu(txh->MacTxControlLow);
667 	mcl &= ~TXC_AMPDU_MASK;
668 	mcl |= (TXC_AMPDU_LAST << TXC_AMPDU_SHIFT);
669 	txh->MacTxControlLow = cpu_to_le16(mcl);
670 
671 	/* remove the null delimiter after last mpdu */
672 	ndelim = txh->RTSPLCPFallback[AMPDU_FBR_NULL_DELIM];
673 	txh->RTSPLCPFallback[AMPDU_FBR_NULL_DELIM] = 0;
674 	session->ampdu_len -= ndelim * AMPDU_DELIMITER_LEN;
675 
676 	/* remove the pad len from last mpdu */
677 	fbr_iscck = ((le16_to_cpu(txh->XtraFrameTypes) & 0x3) == 0);
678 	len = fbr_iscck ? BRCMS_GET_CCK_PLCP_LEN(txh->FragPLCPFallback) :
679 			  BRCMS_GET_MIMO_PLCP_LEN(txh->FragPLCPFallback);
680 	session->ampdu_len -= roundup(len, 4) - len;
681 
682 	/* Now fix up the first MPDU */
683 	tx_info = IEEE80211_SKB_CB(first);
684 	txrate = tx_info->status.rates;
685 	txh = (struct d11txh *)first->data;
686 	plcp = (u8 *)(txh + 1);
687 	rts = (struct ieee80211_rts *)&txh->rts_frame;
688 
689 	mcl = le16_to_cpu(txh->MacTxControlLow);
690 	/* If only one MPDU leave it marked as last */
691 	if (first != last) {
692 		mcl &= ~TXC_AMPDU_MASK;
693 		mcl |= (TXC_AMPDU_FIRST << TXC_AMPDU_SHIFT);
694 	}
695 	mcl |= TXC_STARTMSDU;
696 	if (ieee80211_is_rts(rts->frame_control)) {
697 		mcl |= TXC_SENDRTS;
698 		use_rts = true;
699 	}
700 	if (ieee80211_is_cts(rts->frame_control)) {
701 		mcl |= TXC_SENDCTS;
702 		use_cts = true;
703 	}
704 	txh->MacTxControlLow = cpu_to_le16(mcl);
705 
706 	fbr = txrate[1].count > 0;
707 	if (!fbr)
708 		plcp0 = plcp[0];
709 	else
710 		plcp0 = txh->FragPLCPFallback[0];
711 
712 	is40 = (plcp0 & MIMO_PLCP_40MHZ) ? 1 : 0;
713 	mcs = plcp0 & ~MIMO_PLCP_40MHZ;
714 
715 	if (is40) {
716 		if (CHSPEC_SB_UPPER(wlc_phy_chanspec_get(wlc->band->pi)))
717 			mimo_ctlchbw = PHY_TXC1_BW_20MHZ_UP;
718 		else
719 			mimo_ctlchbw = PHY_TXC1_BW_20MHZ;
720 	}
721 
722 	/* rebuild the rspec and rspec_fallback */
723 	rspec = RSPEC_MIMORATE;
724 	rspec |= plcp[0] & ~MIMO_PLCP_40MHZ;
725 	if (plcp[0] & MIMO_PLCP_40MHZ)
726 		rspec |= (PHY_TXC1_BW_40MHZ << RSPEC_BW_SHIFT);
727 
728 	fbr_iscck = !(le16_to_cpu(txh->XtraFrameTypes) & 0x03);
729 	if (fbr_iscck) {
730 		rspec_fallback =
731 			cck_rspec(cck_phy2mac_rate(txh->FragPLCPFallback[0]));
732 	} else {
733 		rspec_fallback = RSPEC_MIMORATE;
734 		rspec_fallback |= txh->FragPLCPFallback[0] & ~MIMO_PLCP_40MHZ;
735 		if (txh->FragPLCPFallback[0] & MIMO_PLCP_40MHZ)
736 			rspec_fallback |= PHY_TXC1_BW_40MHZ << RSPEC_BW_SHIFT;
737 	}
738 
739 	if (use_rts || use_cts) {
740 		rts_rspec =
741 			brcms_c_rspec_to_rts_rspec(wlc, rspec,
742 						   false, mimo_ctlchbw);
743 		rts_rspec_fallback =
744 			brcms_c_rspec_to_rts_rspec(wlc, rspec_fallback,
745 						   false, mimo_ctlchbw);
746 	}
747 
748 	BRCMS_SET_MIMO_PLCP_LEN(plcp, session->ampdu_len);
749 	/* mark plcp to indicate ampdu */
750 	BRCMS_SET_MIMO_PLCP_AMPDU(plcp);
751 
752 	/* reset the mixed mode header durations */
753 	if (txh->MModeLen) {
754 		u16 mmodelen = brcms_c_calc_lsig_len(wlc, rspec,
755 						     session->ampdu_len);
756 		txh->MModeLen = cpu_to_le16(mmodelen);
757 		preamble_type = BRCMS_MM_PREAMBLE;
758 	}
759 	if (txh->MModeFbrLen) {
760 		u16 mmfbrlen = brcms_c_calc_lsig_len(wlc, rspec_fallback,
761 						     session->ampdu_len);
762 		txh->MModeFbrLen = cpu_to_le16(mmfbrlen);
763 		fbr_preamble_type = BRCMS_MM_PREAMBLE;
764 	}
765 
766 	/* set the preload length */
767 	if (mcs_2_rate(mcs, true, false) >= f->dmaxferrate) {
768 		dma_len = min(dma_len, f->ampdu_pld_size);
769 		txh->PreloadSize = cpu_to_le16(dma_len);
770 	} else {
771 		txh->PreloadSize = 0;
772 	}
773 
774 	mch = le16_to_cpu(txh->MacTxControlHigh);
775 
776 	/* update RTS dur fields */
777 	if (use_rts || use_cts) {
778 		u16 durid;
779 		if ((mch & TXC_PREAMBLE_RTS_MAIN_SHORT) ==
780 		    TXC_PREAMBLE_RTS_MAIN_SHORT)
781 			rts_preamble_type = BRCMS_SHORT_PREAMBLE;
782 
783 		if ((mch & TXC_PREAMBLE_RTS_FB_SHORT) ==
784 		     TXC_PREAMBLE_RTS_FB_SHORT)
785 			rts_fbr_preamble_type = BRCMS_SHORT_PREAMBLE;
786 
787 		durid = brcms_c_compute_rtscts_dur(wlc, use_cts, rts_rspec,
788 						   rspec, rts_preamble_type,
789 						   preamble_type,
790 						   session->ampdu_len, true);
791 		rts->duration = cpu_to_le16(durid);
792 		durid = brcms_c_compute_rtscts_dur(wlc, use_cts,
793 						   rts_rspec_fallback,
794 						   rspec_fallback,
795 						   rts_fbr_preamble_type,
796 						   fbr_preamble_type,
797 						   session->ampdu_len, true);
798 		txh->RTSDurFallback = cpu_to_le16(durid);
799 		/* set TxFesTimeNormal */
800 		txh->TxFesTimeNormal = rts->duration;
801 		/* set fallback rate version of TxFesTimeNormal */
802 		txh->TxFesTimeFallback = txh->RTSDurFallback;
803 	}
804 
805 	/* set flag and plcp for fallback rate */
806 	if (fbr) {
807 		mch |= TXC_AMPDU_FBR;
808 		txh->MacTxControlHigh = cpu_to_le16(mch);
809 		BRCMS_SET_MIMO_PLCP_AMPDU(plcp);
810 		BRCMS_SET_MIMO_PLCP_AMPDU(txh->FragPLCPFallback);
811 	}
812 
813 	brcms_dbg_ht(wlc->hw->d11core, "wl%d: count %d ampdu_len %d\n",
814 		     wlc->pub->unit, skb_queue_len(&session->skb_list),
815 		     session->ampdu_len);
816 }
817 
818 static void
819 brcms_c_ampdu_rate_status(struct brcms_c_info *wlc,
820 			  struct ieee80211_tx_info *tx_info,
821 			  struct tx_status *txs, u8 mcs)
822 {
823 	struct ieee80211_tx_rate *txrate = tx_info->status.rates;
824 	int i;
825 
826 	/* clear the rest of the rates */
827 	for (i = 2; i < IEEE80211_TX_MAX_RATES; i++) {
828 		txrate[i].idx = -1;
829 		txrate[i].count = 0;
830 	}
831 }
832 
833 static void
834 brcms_c_ampdu_dotxstatus_complete(struct ampdu_info *ampdu, struct scb *scb,
835 			      struct sk_buff *p, struct tx_status *txs,
836 			      u32 s1, u32 s2)
837 {
838 	struct scb_ampdu *scb_ampdu;
839 	struct brcms_c_info *wlc = ampdu->wlc;
840 	struct scb_ampdu_tid_ini *ini;
841 	u8 bitmap[8], queue, tid;
842 	struct d11txh *txh;
843 	u8 *plcp;
844 	struct ieee80211_hdr *h;
845 	u16 seq, start_seq = 0, bindex, index, mcl;
846 	u8 mcs = 0;
847 	bool ba_recd = false, ack_recd = false;
848 	u8 suc_mpdu = 0, tot_mpdu = 0;
849 	uint supr_status;
850 	bool retry = true;
851 	u16 mimoantsel = 0;
852 	u8 retry_limit;
853 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(p);
854 
855 #ifdef DEBUG
856 	u8 hole[AMPDU_MAX_MPDU];
857 	memset(hole, 0, sizeof(hole));
858 #endif
859 
860 	scb_ampdu = &scb->scb_ampdu;
861 	tid = (u8) (p->priority);
862 
863 	ini = &scb_ampdu->ini[tid];
864 	retry_limit = ampdu->retry_limit_tid[tid];
865 	memset(bitmap, 0, sizeof(bitmap));
866 	queue = txs->frameid & TXFID_QUEUE_MASK;
867 	supr_status = txs->status & TX_STATUS_SUPR_MASK;
868 
869 	if (txs->status & TX_STATUS_ACK_RCV) {
870 		WARN_ON(!(txs->status & TX_STATUS_INTERMEDIATE));
871 		start_seq = txs->sequence >> SEQNUM_SHIFT;
872 		bitmap[0] = (txs->status & TX_STATUS_BA_BMAP03_MASK) >>
873 		    TX_STATUS_BA_BMAP03_SHIFT;
874 
875 		WARN_ON(s1 & TX_STATUS_INTERMEDIATE);
876 		WARN_ON(!(s1 & TX_STATUS_AMPDU));
877 
878 		bitmap[0] |=
879 		    (s1 & TX_STATUS_BA_BMAP47_MASK) <<
880 		    TX_STATUS_BA_BMAP47_SHIFT;
881 		bitmap[1] = (s1 >> 8) & 0xff;
882 		bitmap[2] = (s1 >> 16) & 0xff;
883 		bitmap[3] = (s1 >> 24) & 0xff;
884 
885 		bitmap[4] = s2 & 0xff;
886 		bitmap[5] = (s2 >> 8) & 0xff;
887 		bitmap[6] = (s2 >> 16) & 0xff;
888 		bitmap[7] = (s2 >> 24) & 0xff;
889 
890 		ba_recd = true;
891 	} else {
892 		if (supr_status) {
893 			if (supr_status == TX_STATUS_SUPR_BADCH) {
894 				brcms_dbg_ht(wlc->hw->d11core,
895 					  "%s: Pkt tx suppressed, illegal channel possibly %d\n",
896 					  __func__, CHSPEC_CHANNEL(
897 					  wlc->default_bss->chanspec));
898 			} else {
899 				if (supr_status != TX_STATUS_SUPR_FRAG)
900 					brcms_err(wlc->hw->d11core,
901 						  "%s: supr_status 0x%x\n",
902 						  __func__, supr_status);
903 			}
904 			/* no need to retry for badch; will fail again */
905 			if (supr_status == TX_STATUS_SUPR_BADCH ||
906 			    supr_status == TX_STATUS_SUPR_EXPTIME) {
907 				retry = false;
908 			} else if (supr_status == TX_STATUS_SUPR_EXPTIME) {
909 				/* TX underflow:
910 				 *   try tuning pre-loading or ampdu size
911 				 */
912 			} else if (supr_status == TX_STATUS_SUPR_FRAG) {
913 				/*
914 				 * if there were underflows, but pre-loading
915 				 * is not active, notify rate adaptation.
916 				 */
917 				brcms_c_ffpld_check_txfunfl(wlc, queue);
918 			}
919 		} else if (txs->phyerr) {
920 			brcms_dbg_ht(wlc->hw->d11core,
921 				     "%s: ampdu tx phy error (0x%x)\n",
922 				     __func__, txs->phyerr);
923 		}
924 	}
925 
926 	/* loop through all pkts and retry if not acked */
927 	while (p) {
928 		tx_info = IEEE80211_SKB_CB(p);
929 		txh = (struct d11txh *) p->data;
930 		mcl = le16_to_cpu(txh->MacTxControlLow);
931 		plcp = (u8 *) (txh + 1);
932 		h = (struct ieee80211_hdr *)(plcp + D11_PHY_HDR_LEN);
933 		seq = le16_to_cpu(h->seq_ctrl) >> SEQNUM_SHIFT;
934 
935 		trace_brcms_txdesc(&wlc->hw->d11core->dev, txh, sizeof(*txh));
936 
937 		if (tot_mpdu == 0) {
938 			mcs = plcp[0] & MIMO_PLCP_MCS_MASK;
939 			mimoantsel = le16_to_cpu(txh->ABI_MimoAntSel);
940 		}
941 
942 		index = TX_SEQ_TO_INDEX(seq);
943 		ack_recd = false;
944 		if (ba_recd) {
945 			int block_acked;
946 
947 			bindex = MODSUB_POW2(seq, start_seq, SEQNUM_MAX);
948 			if (bindex < AMPDU_TX_BA_MAX_WSIZE)
949 				block_acked = isset(bitmap, bindex);
950 			else
951 				block_acked = 0;
952 			brcms_dbg_ht(wlc->hw->d11core,
953 				     "tid %d seq %d, start_seq %d, bindex %d set %d, index %d\n",
954 				     tid, seq, start_seq, bindex,
955 				     block_acked, index);
956 			/* if acked then clear bit and free packet */
957 			if (block_acked) {
958 				ini->txretry[index] = 0;
959 
960 				/*
961 				 * ampdu_ack_len:
962 				 *   number of acked aggregated frames
963 				 */
964 				/* ampdu_len: number of aggregated frames */
965 				brcms_c_ampdu_rate_status(wlc, tx_info, txs,
966 							  mcs);
967 				tx_info->flags |= IEEE80211_TX_STAT_ACK;
968 				tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
969 				tx_info->status.ampdu_ack_len =
970 					tx_info->status.ampdu_len = 1;
971 
972 				skb_pull(p, D11_PHY_HDR_LEN);
973 				skb_pull(p, D11_TXH_LEN);
974 
975 				ieee80211_tx_status_irqsafe(wlc->pub->ieee_hw,
976 							    p);
977 				ack_recd = true;
978 				suc_mpdu++;
979 			}
980 		}
981 		/* either retransmit or send bar if ack not recd */
982 		if (!ack_recd) {
983 			if (retry && (ini->txretry[index] < (int)retry_limit)) {
984 				int ret;
985 				ini->txretry[index]++;
986 				ret = brcms_c_txfifo(wlc, queue, p);
987 				/*
988 				 * We shouldn't be out of space in the DMA
989 				 * ring here since we're reinserting a frame
990 				 * that was just pulled out.
991 				 */
992 				WARN_ONCE(ret, "queue %d out of txds\n", queue);
993 			} else {
994 				/* Retry timeout */
995 				ieee80211_tx_info_clear_status(tx_info);
996 				tx_info->status.ampdu_ack_len = 0;
997 				tx_info->status.ampdu_len = 1;
998 				tx_info->flags |=
999 				    IEEE80211_TX_STAT_AMPDU_NO_BACK;
1000 				skb_pull(p, D11_PHY_HDR_LEN);
1001 				skb_pull(p, D11_TXH_LEN);
1002 				brcms_dbg_ht(wlc->hw->d11core,
1003 					     "BA Timeout, seq %d\n",
1004 					     seq);
1005 				ieee80211_tx_status_irqsafe(wlc->pub->ieee_hw,
1006 							    p);
1007 			}
1008 		}
1009 		tot_mpdu++;
1010 
1011 		/* break out if last packet of ampdu */
1012 		if (((mcl & TXC_AMPDU_MASK) >> TXC_AMPDU_SHIFT) ==
1013 		    TXC_AMPDU_LAST)
1014 			break;
1015 
1016 		p = dma_getnexttxp(wlc->hw->di[queue], DMA_RANGE_TRANSMITTED);
1017 	}
1018 
1019 	/* update rate state */
1020 	brcms_c_antsel_antsel2id(wlc->asi, mimoantsel);
1021 }
1022 
1023 void
1024 brcms_c_ampdu_dotxstatus(struct ampdu_info *ampdu, struct scb *scb,
1025 		     struct sk_buff *p, struct tx_status *txs)
1026 {
1027 	struct brcms_c_info *wlc = ampdu->wlc;
1028 	u32 s1 = 0, s2 = 0;
1029 
1030 	/* BMAC_NOTE: For the split driver, second level txstatus comes later
1031 	 * So if the ACK was received then wait for the second level else just
1032 	 * call the first one
1033 	 */
1034 	if (txs->status & TX_STATUS_ACK_RCV) {
1035 		u8 status_delay = 0;
1036 
1037 		/* wait till the next 8 bytes of txstatus is available */
1038 		s1 = bcma_read32(wlc->hw->d11core, D11REGOFFS(frmtxstatus));
1039 		while ((s1 & TXS_V) == 0) {
1040 			udelay(1);
1041 			status_delay++;
1042 			if (status_delay > 10)
1043 				return; /* error condition */
1044 			s1 = bcma_read32(wlc->hw->d11core,
1045 					 D11REGOFFS(frmtxstatus));
1046 		}
1047 
1048 		s2 = bcma_read32(wlc->hw->d11core, D11REGOFFS(frmtxstatus2));
1049 	}
1050 
1051 	if (scb) {
1052 		brcms_c_ampdu_dotxstatus_complete(ampdu, scb, p, txs, s1, s2);
1053 	} else {
1054 		/* loop through all pkts and free */
1055 		u8 queue = txs->frameid & TXFID_QUEUE_MASK;
1056 		struct d11txh *txh;
1057 		u16 mcl;
1058 		while (p) {
1059 			txh = (struct d11txh *) p->data;
1060 			trace_brcms_txdesc(&wlc->hw->d11core->dev, txh,
1061 					   sizeof(*txh));
1062 			mcl = le16_to_cpu(txh->MacTxControlLow);
1063 			brcmu_pkt_buf_free_skb(p);
1064 			/* break out if last packet of ampdu */
1065 			if (((mcl & TXC_AMPDU_MASK) >> TXC_AMPDU_SHIFT) ==
1066 			    TXC_AMPDU_LAST)
1067 				break;
1068 			p = dma_getnexttxp(wlc->hw->di[queue],
1069 					   DMA_RANGE_TRANSMITTED);
1070 		}
1071 	}
1072 }
1073 
1074 void brcms_c_ampdu_macaddr_upd(struct brcms_c_info *wlc)
1075 {
1076 	char template[T_RAM_ACCESS_SZ * 2];
1077 
1078 	/* driver needs to write the ta in the template; ta is at offset 16 */
1079 	memset(template, 0, sizeof(template));
1080 	memcpy(template, wlc->pub->cur_etheraddr, ETH_ALEN);
1081 	brcms_b_write_template_ram(wlc->hw, (T_BA_TPL_BASE + 16),
1082 				  (T_RAM_ACCESS_SZ * 2),
1083 				  template);
1084 }
1085 
1086 bool brcms_c_aggregatable(struct brcms_c_info *wlc, u8 tid)
1087 {
1088 	return wlc->ampdu->ini_enable[tid];
1089 }
1090 
1091 void brcms_c_ampdu_shm_upd(struct ampdu_info *ampdu)
1092 {
1093 	struct brcms_c_info *wlc = ampdu->wlc;
1094 
1095 	/*
1096 	 * Extend ucode internal watchdog timer to
1097 	 * match larger received frames
1098 	 */
1099 	if ((ampdu->rx_factor & IEEE80211_HT_AMPDU_PARM_FACTOR) ==
1100 	    IEEE80211_HT_MAX_AMPDU_64K) {
1101 		brcms_b_write_shm(wlc->hw, M_MIMO_MAXSYM, MIMO_MAXSYM_MAX);
1102 		brcms_b_write_shm(wlc->hw, M_WATCHDOG_8TU, WATCHDOG_8TU_MAX);
1103 	} else {
1104 		brcms_b_write_shm(wlc->hw, M_MIMO_MAXSYM, MIMO_MAXSYM_DEF);
1105 		brcms_b_write_shm(wlc->hw, M_WATCHDOG_8TU, WATCHDOG_8TU_DEF);
1106 	}
1107 }
1108 
1109 /*
1110  * callback function that helps invalidating ampdu packets in a DMA queue
1111  */
1112 static void dma_cb_fn_ampdu(void *txi, void *arg_a)
1113 {
1114 	struct ieee80211_sta *sta = arg_a;
1115 	struct ieee80211_tx_info *tx_info = (struct ieee80211_tx_info *)txi;
1116 
1117 	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) &&
1118 	    (tx_info->rate_driver_data[0] == sta || sta == NULL))
1119 		tx_info->rate_driver_data[0] = NULL;
1120 }
1121 
1122 /*
1123  * When a remote party is no longer available for ampdu communication, any
1124  * pending tx ampdu packets in the driver have to be flushed.
1125  */
1126 void brcms_c_ampdu_flush(struct brcms_c_info *wlc,
1127 		     struct ieee80211_sta *sta, u16 tid)
1128 {
1129 	brcms_c_inval_dma_pkts(wlc->hw, sta, dma_cb_fn_ampdu);
1130 }
1131