xref: /freebsd/sys/dev/ath/if_ath_tx_edma.c (revision 315ee00f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2012 Adrian Chadd <adrian@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer,
12  *    without modification.
13  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14  *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
15  *    redistribution must be conditioned upon including a substantially
16  *    similar Disclaimer requirement for further binary redistribution.
17  *
18  * NO WARRANTY
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
22  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23  * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
24  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
27  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29  * THE POSSIBILITY OF SUCH DAMAGES.
30  */
31 
32 #include <sys/cdefs.h>
33 /*
34  * Driver for the Atheros Wireless LAN controller.
35  *
36  * This software is derived from work of Atsushi Onoe; his contribution
37  * is greatly appreciated.
38  */
39 
40 #include "opt_inet.h"
41 #include "opt_ath.h"
42 /*
43  * This is needed for register operations which are performed
44  * by the driver - eg, calls to ath_hal_gettsf32().
45  *
46  * It's also required for any AH_DEBUG checks in here, eg the
47  * module dependencies.
48  */
49 #include "opt_ah.h"
50 #include "opt_wlan.h"
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/sysctl.h>
55 #include <sys/mbuf.h>
56 #include <sys/malloc.h>
57 #include <sys/lock.h>
58 #include <sys/mutex.h>
59 #include <sys/kernel.h>
60 #include <sys/socket.h>
61 #include <sys/sockio.h>
62 #include <sys/errno.h>
63 #include <sys/callout.h>
64 #include <sys/bus.h>
65 #include <sys/endian.h>
66 #include <sys/kthread.h>
67 #include <sys/taskqueue.h>
68 #include <sys/priv.h>
69 #include <sys/module.h>
70 #include <sys/ktr.h>
71 #include <sys/smp.h>	/* for mp_ncpus */
72 
73 #include <machine/bus.h>
74 
75 #include <net/if.h>
76 #include <net/if_var.h>
77 #include <net/if_dl.h>
78 #include <net/if_media.h>
79 #include <net/if_types.h>
80 #include <net/if_arp.h>
81 #include <net/ethernet.h>
82 #include <net/if_llc.h>
83 
84 #include <net80211/ieee80211_var.h>
85 #include <net80211/ieee80211_regdomain.h>
86 #ifdef IEEE80211_SUPPORT_SUPERG
87 #include <net80211/ieee80211_superg.h>
88 #endif
89 #ifdef IEEE80211_SUPPORT_TDMA
90 #include <net80211/ieee80211_tdma.h>
91 #endif
92 
93 #include <net/bpf.h>
94 
95 #ifdef INET
96 #include <netinet/in.h>
97 #include <netinet/if_ether.h>
98 #endif
99 
100 #include <dev/ath/if_athvar.h>
101 #include <dev/ath/ath_hal/ah_devid.h>		/* XXX for softled */
102 #include <dev/ath/ath_hal/ah_diagcodes.h>
103 
104 #include <dev/ath/if_ath_debug.h>
105 #include <dev/ath/if_ath_misc.h>
106 #include <dev/ath/if_ath_tsf.h>
107 #include <dev/ath/if_ath_tx.h>
108 #include <dev/ath/if_ath_sysctl.h>
109 #include <dev/ath/if_ath_led.h>
110 #include <dev/ath/if_ath_keycache.h>
111 #include <dev/ath/if_ath_rx.h>
112 #include <dev/ath/if_ath_beacon.h>
113 #include <dev/ath/if_athdfs.h>
114 #include <dev/ath/if_ath_descdma.h>
115 
116 #ifdef ATH_TX99_DIAG
117 #include <dev/ath/ath_tx99/ath_tx99.h>
118 #endif
119 
120 #include <dev/ath/if_ath_tx_edma.h>
121 
122 #ifdef	ATH_DEBUG_ALQ
123 #include <dev/ath/if_ath_alq.h>
124 #endif
125 
126 /*
127  * some general macros
128  */
129 #define	INCR(_l, _sz)		(_l) ++; (_l) &= ((_sz) - 1)
130 #define	DECR(_l, _sz)		(_l) --; (_l) &= ((_sz) - 1)
131 
132 /*
133  * XXX doesn't belong here, and should be tunable
134  */
135 #define	ATH_TXSTATUS_RING_SIZE	512
136 
137 MALLOC_DECLARE(M_ATHDEV);
138 
139 static void ath_edma_tx_processq(struct ath_softc *sc, int dosched);
140 
141 #ifdef	ATH_DEBUG_ALQ
142 static void
143 ath_tx_alq_edma_push(struct ath_softc *sc, int txq, int nframes,
144     int fifo_depth, int frame_cnt)
145 {
146 	struct if_ath_alq_tx_fifo_push aq;
147 
148 	aq.txq = htobe32(txq);
149 	aq.nframes = htobe32(nframes);
150 	aq.fifo_depth = htobe32(fifo_depth);
151 	aq.frame_cnt = htobe32(frame_cnt);
152 
153 	if_ath_alq_post(&sc->sc_alq, ATH_ALQ_TX_FIFO_PUSH,
154 	    sizeof(aq),
155 	    (const char *) &aq);
156 }
157 #endif	/* ATH_DEBUG_ALQ */
158 
159 /*
160  * XXX TODO: push an aggregate as a single FIFO slot, even though
161  * it may not meet the TXOP for say, DBA-gated traffic in TDMA mode.
162  *
163  * The TX completion code handles a TX FIFO slot having multiple frames,
164  * aggregate or otherwise, but it may just make things easier to deal
165  * with.
166  *
167  * XXX TODO: track the number of aggregate subframes and put that in the
168  * push alq message.
169  */
170 static void
171 ath_tx_edma_push_staging_list(struct ath_softc *sc, struct ath_txq *txq,
172     int limit)
173 {
174 	struct ath_buf *bf, *bf_last;
175 	struct ath_buf *bfi, *bfp;
176 	int i, sqdepth;
177 	TAILQ_HEAD(axq_q_f_s, ath_buf)  sq;
178 
179 	ATH_TXQ_LOCK_ASSERT(txq);
180 
181 	DPRINTF(sc, ATH_DEBUG_XMIT | ATH_DEBUG_TX_PROC,
182 	    "%s: called; TXQ=%d, fifo.depth=%d, axq_q empty=%d\n",
183 	    __func__,
184 	    txq->axq_qnum,
185 	    txq->axq_fifo_depth,
186 	    !! (TAILQ_EMPTY(&txq->axq_q)));
187 
188 	/*
189 	 * Don't bother doing any work if it's full.
190 	 */
191 	if (txq->axq_fifo_depth >= HAL_TXFIFO_DEPTH)
192 		return;
193 
194 	if (TAILQ_EMPTY(&txq->axq_q))
195 		return;
196 
197 	TAILQ_INIT(&sq);
198 
199 	/*
200 	 * First pass - walk sq, queue up to 'limit' entries,
201 	 * subtract them from the staging queue.
202 	 */
203 	sqdepth = 0;
204 	for (i = 0; i < limit; i++) {
205 		/* Grab the head entry */
206 		bf = ATH_TXQ_FIRST(txq);
207 		if (bf == NULL)
208 			break;
209 		ATH_TXQ_REMOVE(txq, bf, bf_list);
210 
211 		/* Queue it into our staging list */
212 		TAILQ_INSERT_TAIL(&sq, bf, bf_list);
213 
214 		/* Ensure the flags are cleared */
215 		bf->bf_flags &= ~(ATH_BUF_FIFOPTR | ATH_BUF_FIFOEND);
216 		sqdepth++;
217 	}
218 
219 	/*
220 	 * Ok, so now we have a staging list of up to 'limit'
221 	 * frames from the txq.  Now let's wrap that up
222 	 * into its own list and pass that to the hardware
223 	 * as one FIFO entry.
224 	 */
225 
226 	bf = TAILQ_FIRST(&sq);
227 	bf_last = TAILQ_LAST(&sq, axq_q_s);
228 
229 	/*
230 	 * Ok, so here's the gymnastics reqiured to make this
231 	 * all sensible.
232 	 */
233 
234 	/*
235 	 * Tag the first/last buffer appropriately.
236 	 */
237 	bf->bf_flags |= ATH_BUF_FIFOPTR;
238 	bf_last->bf_flags |= ATH_BUF_FIFOEND;
239 
240 	/*
241 	 * Walk the descriptor list and link them appropriately.
242 	 */
243 	bfp = NULL;
244 	TAILQ_FOREACH(bfi, &sq, bf_list) {
245 		if (bfp != NULL) {
246 			ath_hal_settxdesclink(sc->sc_ah, bfp->bf_lastds,
247 			    bfi->bf_daddr);
248 		}
249 		bfp = bfi;
250 	}
251 
252 	i = 0;
253 	TAILQ_FOREACH(bfi, &sq, bf_list) {
254 #ifdef	ATH_DEBUG
255 		if (sc->sc_debug & ATH_DEBUG_XMIT_DESC)
256 			ath_printtxbuf(sc, bfi, txq->axq_qnum, i, 0);
257 #endif/* ATH_DEBUG */
258 #ifdef	ATH_DEBUG_ALQ
259 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
260 			ath_tx_alq_post(sc, bfi);
261 #endif /* ATH_DEBUG_ALQ */
262 		i++;
263 	}
264 
265 	/*
266 	 * We now need to push this set of frames onto the tail
267 	 * of the FIFO queue.  We don't adjust the aggregate
268 	 * count, only the queue depth counter(s).
269 	 * We also need to blank the link pointer now.
270 	 */
271 
272 	TAILQ_CONCAT(&txq->fifo.axq_q, &sq, bf_list);
273 	/* Bump total queue tracking in FIFO queue */
274 	txq->fifo.axq_depth += sqdepth;
275 
276 	/* Bump FIFO queue */
277 	txq->axq_fifo_depth++;
278 	DPRINTF(sc, ATH_DEBUG_XMIT | ATH_DEBUG_TX_PROC,
279 	    "%s: queued %d packets; depth=%d, fifo depth=%d\n",
280 	    __func__, sqdepth, txq->fifo.axq_depth, txq->axq_fifo_depth);
281 
282 	/* Push the first entry into the hardware */
283 	ath_hal_puttxbuf(sc->sc_ah, txq->axq_qnum, bf->bf_daddr);
284 
285 	/* Push start on the DMA if it's not already started */
286 	ath_hal_txstart(sc->sc_ah, txq->axq_qnum);
287 
288 #ifdef	ATH_DEBUG_ALQ
289 	ath_tx_alq_edma_push(sc, txq->axq_qnum, sqdepth,
290 	    txq->axq_fifo_depth,
291 	    txq->fifo.axq_depth);
292 #endif /* ATH_DEBUG_ALQ */
293 }
294 
295 #define	TX_BATCH_SIZE	32
296 
297 /*
298  * Push some frames into the TX FIFO if we have space.
299  */
300 static void
301 ath_edma_tx_fifo_fill(struct ath_softc *sc, struct ath_txq *txq)
302 {
303 
304 	ATH_TXQ_LOCK_ASSERT(txq);
305 
306 	DPRINTF(sc, ATH_DEBUG_TX_PROC,
307 	    "%s: Q%d: called; fifo.depth=%d, fifo depth=%d, depth=%d, aggr_depth=%d\n",
308 	    __func__,
309 	    txq->axq_qnum,
310 	    txq->fifo.axq_depth,
311 	    txq->axq_fifo_depth,
312 	    txq->axq_depth,
313 	    txq->axq_aggr_depth);
314 
315 	/*
316 	 * For now, push up to 32 frames per TX FIFO slot.
317 	 * If more are in the hardware queue then they'll
318 	 * get populated when we try to send another frame
319 	 * or complete a frame - so at most there'll be
320 	 * 32 non-AMPDU frames per node/TID anyway.
321 	 *
322 	 * Note that the hardware staging queue will limit
323 	 * how many frames in total we will have pushed into
324 	 * here.
325 	 *
326 	 * Later on, we'll want to push less frames into
327 	 * the TX FIFO since we don't want to necessarily
328 	 * fill tens or hundreds of milliseconds of potential
329 	 * frames.
330 	 *
331 	 * However, we need more frames right now because of
332 	 * how the MAC implements the frame scheduling policy.
333 	 * It only ungates a single FIFO entry at a time,
334 	 * and will run that until CHNTIME expires or the
335 	 * end of that FIFO entry descriptor list is reached.
336 	 * So for TDMA we suffer a big performance penalty -
337 	 * single TX FIFO entries mean the MAC only sends out
338 	 * one frame per DBA event, which turned out on average
339 	 * 6ms per TX frame.
340 	 *
341 	 * So, for aggregates it's okay - it'll push two at a
342 	 * time and this will just do them more efficiently.
343 	 * For non-aggregates it'll do 4 at a time, up to the
344 	 * non-aggr limit (non_aggr, which is 32.)  They should
345 	 * be time based rather than a hard count, but I also
346 	 * do need sleep.
347 	 */
348 
349 	/*
350 	 * Do some basic, basic batching to the hardware
351 	 * queue.
352 	 *
353 	 * If we have TX_BATCH_SIZE entries in the staging
354 	 * queue, then let's try to send them all in one hit.
355 	 *
356 	 * Ensure we don't push more than TX_BATCH_SIZE worth
357 	 * in, otherwise we end up draining 8 slots worth of
358 	 * 32 frames into the hardware queue and then we don't
359 	 * attempt to push more frames in until we empty the
360 	 * FIFO.
361 	 */
362 	if (txq->axq_depth >= TX_BATCH_SIZE / 2 &&
363 	    txq->fifo.axq_depth <= TX_BATCH_SIZE) {
364 		ath_tx_edma_push_staging_list(sc, txq, TX_BATCH_SIZE);
365 	}
366 
367 	/*
368 	 * Aggregate check: if we have less than two FIFO slots
369 	 * busy and we have some aggregate frames, queue it.
370 	 *
371 	 * Now, ideally we'd just check to see if the scheduler
372 	 * has given us aggregate frames and push them into the FIFO
373 	 * as individual slots, as honestly we should just be pushing
374 	 * a single aggregate in as one FIFO slot.
375 	 *
376 	 * Let's do that next once I know this works.
377 	 */
378 	else if (txq->axq_aggr_depth > 0 && txq->axq_fifo_depth < 2)
379 		ath_tx_edma_push_staging_list(sc, txq, TX_BATCH_SIZE);
380 
381 	/*
382 	 *
383 	 * If we have less, and the TXFIFO isn't empty, let's
384 	 * wait until we've finished sending the FIFO.
385 	 *
386 	 * If we have less, and the TXFIFO is empty, then
387 	 * send them.
388 	 */
389 	else if (txq->axq_fifo_depth == 0) {
390 		ath_tx_edma_push_staging_list(sc, txq, TX_BATCH_SIZE);
391 	}
392 }
393 
394 /*
395  * Re-initialise the DMA FIFO with the current contents of
396  * said TXQ.
397  *
398  * This should only be called as part of the chip reset path, as it
399  * assumes the FIFO is currently empty.
400  */
401 static void
402 ath_edma_dma_restart(struct ath_softc *sc, struct ath_txq *txq)
403 {
404 	struct ath_buf *bf;
405 	int i = 0;
406 	int fifostart = 1;
407 	int old_fifo_depth;
408 
409 	DPRINTF(sc, ATH_DEBUG_RESET, "%s: Q%d: called\n",
410 	    __func__,
411 	    txq->axq_qnum);
412 
413 	ATH_TXQ_LOCK_ASSERT(txq);
414 
415 	/*
416 	 * Let's log if the tracked FIFO depth doesn't match
417 	 * what we actually push in.
418 	 */
419 	old_fifo_depth = txq->axq_fifo_depth;
420 	txq->axq_fifo_depth = 0;
421 
422 	/*
423 	 * Walk the FIFO staging list, looking for "head" entries.
424 	 * Since we may have a partially completed list of frames,
425 	 * we push the first frame we see into the FIFO and re-mark
426 	 * it as the head entry.  We then skip entries until we see
427 	 * FIFO end, at which point we get ready to push another
428 	 * entry into the FIFO.
429 	 */
430 	TAILQ_FOREACH(bf, &txq->fifo.axq_q, bf_list) {
431 		/*
432 		 * If we're looking for FIFOEND and we haven't found
433 		 * it, skip.
434 		 *
435 		 * If we're looking for FIFOEND and we've found it,
436 		 * reset for another descriptor.
437 		 */
438 #ifdef	ATH_DEBUG
439 		if (sc->sc_debug & ATH_DEBUG_XMIT_DESC)
440 			ath_printtxbuf(sc, bf, txq->axq_qnum, i, 0);
441 #endif/* ATH_DEBUG */
442 #ifdef	ATH_DEBUG_ALQ
443 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
444 			ath_tx_alq_post(sc, bf);
445 #endif /* ATH_DEBUG_ALQ */
446 
447 		if (fifostart == 0) {
448 			if (bf->bf_flags & ATH_BUF_FIFOEND)
449 				fifostart = 1;
450 			continue;
451 		}
452 
453 		/* Make sure we're not overflowing the FIFO! */
454 		if (txq->axq_fifo_depth >= HAL_TXFIFO_DEPTH) {
455 			device_printf(sc->sc_dev,
456 			    "%s: Q%d: more frames in the queue; FIFO depth=%d?!\n",
457 			    __func__,
458 			    txq->axq_qnum,
459 			    txq->axq_fifo_depth);
460 		}
461 
462 #if 0
463 		DPRINTF(sc, ATH_DEBUG_RESET,
464 		    "%s: Q%d: depth=%d: pushing bf=%p; start=%d, end=%d\n",
465 		    __func__,
466 		    txq->axq_qnum,
467 		    txq->axq_fifo_depth,
468 		    bf,
469 		    !! (bf->bf_flags & ATH_BUF_FIFOPTR),
470 		    !! (bf->bf_flags & ATH_BUF_FIFOEND));
471 #endif
472 
473 		/*
474 		 * Set this to be the first buffer in the FIFO
475 		 * list - even if it's also the last buffer in
476 		 * a FIFO list!
477 		 */
478 		bf->bf_flags |= ATH_BUF_FIFOPTR;
479 
480 		/* Push it into the FIFO and bump the FIFO count */
481 		ath_hal_puttxbuf(sc->sc_ah, txq->axq_qnum, bf->bf_daddr);
482 		txq->axq_fifo_depth++;
483 
484 		/*
485 		 * If this isn't the last entry either, let's
486 		 * clear fifostart so we continue looking for
487 		 * said last entry.
488 		 */
489 		if (! (bf->bf_flags & ATH_BUF_FIFOEND))
490 			fifostart = 0;
491 		i++;
492 	}
493 
494 	/* Only bother starting the queue if there's something in it */
495 	if (i > 0)
496 		ath_hal_txstart(sc->sc_ah, txq->axq_qnum);
497 
498 	DPRINTF(sc, ATH_DEBUG_RESET, "%s: Q%d: FIFO depth was %d, is %d\n",
499 	    __func__,
500 	    txq->axq_qnum,
501 	    old_fifo_depth,
502 	    txq->axq_fifo_depth);
503 
504 	/* And now, let's check! */
505 	if (txq->axq_fifo_depth != old_fifo_depth) {
506 		device_printf(sc->sc_dev,
507 		    "%s: Q%d: FIFO depth should be %d, is %d\n",
508 		    __func__,
509 		    txq->axq_qnum,
510 		    old_fifo_depth,
511 		    txq->axq_fifo_depth);
512 	}
513 }
514 
515 /*
516  * Hand off this frame to a hardware queue.
517  *
518  * Things are a bit hairy in the EDMA world.  The TX FIFO is only
519  * 8 entries deep, so we need to keep track of exactly what we've
520  * pushed into the FIFO and what's just sitting in the TX queue,
521  * waiting to go out.
522  *
523  * So this is split into two halves - frames get appended to the
524  * TXQ; then a scheduler is called to push some frames into the
525  * actual TX FIFO.
526  */
527 static void
528 ath_edma_xmit_handoff_hw(struct ath_softc *sc, struct ath_txq *txq,
529     struct ath_buf *bf)
530 {
531 
532 	ATH_TXQ_LOCK(txq);
533 
534 	KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
535 	    ("%s: busy status 0x%x", __func__, bf->bf_flags));
536 
537 	/*
538 	 * XXX TODO: write a hard-coded check to ensure that
539 	 * the queue id in the TX descriptor matches txq->axq_qnum.
540 	 */
541 
542 	/* Update aggr stats */
543 	if (bf->bf_state.bfs_aggr)
544 		txq->axq_aggr_depth++;
545 
546 	/* Push and update frame stats */
547 	ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
548 
549 	/*
550 	 * Finally, call the FIFO schedule routine to schedule some
551 	 * frames to the FIFO.
552 	 */
553 	ath_edma_tx_fifo_fill(sc, txq);
554 	ATH_TXQ_UNLOCK(txq);
555 }
556 
557 /*
558  * Hand off this frame to a multicast software queue.
559  *
560  * The EDMA TX CABQ will get a list of chained frames, chained
561  * together using the next pointer.  The single head of that
562  * particular queue is pushed to the hardware CABQ.
563  */
564 static void
565 ath_edma_xmit_handoff_mcast(struct ath_softc *sc, struct ath_txq *txq,
566     struct ath_buf *bf)
567 {
568 
569 	ATH_TX_LOCK_ASSERT(sc);
570 	KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
571 	    ("%s: busy status 0x%x", __func__, bf->bf_flags));
572 
573 	ATH_TXQ_LOCK(txq);
574 	/*
575 	 * XXX this is mostly duplicated in ath_tx_handoff_mcast().
576 	 */
577 	if (ATH_TXQ_LAST(txq, axq_q_s) != NULL) {
578 		struct ath_buf *bf_last = ATH_TXQ_LAST(txq, axq_q_s);
579 		struct ieee80211_frame *wh;
580 
581 		/* mark previous frame */
582 		wh = mtod(bf_last->bf_m, struct ieee80211_frame *);
583 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
584 
585 		/* re-sync buffer to memory */
586 		bus_dmamap_sync(sc->sc_dmat, bf_last->bf_dmamap,
587 		   BUS_DMASYNC_PREWRITE);
588 
589 		/* link descriptor */
590 		ath_hal_settxdesclink(sc->sc_ah,
591 		    bf_last->bf_lastds,
592 		    bf->bf_daddr);
593 	}
594 #ifdef	ATH_DEBUG_ALQ
595 	if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
596 		ath_tx_alq_post(sc, bf);
597 #endif	/* ATH_DEBUG_ALQ */
598 	ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
599 	ATH_TXQ_UNLOCK(txq);
600 }
601 
602 /*
603  * Handoff this frame to the hardware.
604  *
605  * For the multicast queue, this will treat it as a software queue
606  * and append it to the list, after updating the MORE_DATA flag
607  * in the previous frame.  The cabq processing code will ensure
608  * that the queue contents gets transferred over.
609  *
610  * For the hardware queues, this will queue a frame to the queue
611  * like before, then populate the FIFO from that.  Since the
612  * EDMA hardware has 8 FIFO slots per TXQ, this ensures that
613  * frames such as management frames don't get prematurely dropped.
614  *
615  * This does imply that a similar flush-hwq-to-fifoq method will
616  * need to be called from the processq function, before the
617  * per-node software scheduler is called.
618  */
619 static void
620 ath_edma_xmit_handoff(struct ath_softc *sc, struct ath_txq *txq,
621     struct ath_buf *bf)
622 {
623 
624 	DPRINTF(sc, ATH_DEBUG_XMIT_DESC,
625 	    "%s: called; bf=%p, txq=%p, qnum=%d\n",
626 	    __func__,
627 	    bf,
628 	    txq,
629 	    txq->axq_qnum);
630 
631 	if (txq->axq_qnum == ATH_TXQ_SWQ)
632 		ath_edma_xmit_handoff_mcast(sc, txq, bf);
633 	else
634 		ath_edma_xmit_handoff_hw(sc, txq, bf);
635 }
636 
637 static int
638 ath_edma_setup_txfifo(struct ath_softc *sc, int qnum)
639 {
640 	struct ath_tx_edma_fifo *te = &sc->sc_txedma[qnum];
641 
642 	te->m_fifo = malloc(sizeof(struct ath_buf *) * HAL_TXFIFO_DEPTH,
643 	    M_ATHDEV,
644 	    M_NOWAIT | M_ZERO);
645 	if (te->m_fifo == NULL) {
646 		device_printf(sc->sc_dev, "%s: malloc failed\n",
647 		    __func__);
648 		return (-ENOMEM);
649 	}
650 
651 	/*
652 	 * Set initial "empty" state.
653 	 */
654 	te->m_fifo_head = te->m_fifo_tail = te->m_fifo_depth = 0;
655 
656 	return (0);
657 }
658 
659 static int
660 ath_edma_free_txfifo(struct ath_softc *sc, int qnum)
661 {
662 	struct ath_tx_edma_fifo *te = &sc->sc_txedma[qnum];
663 
664 	/* XXX TODO: actually deref the ath_buf entries? */
665 	free(te->m_fifo, M_ATHDEV);
666 	return (0);
667 }
668 
669 static int
670 ath_edma_dma_txsetup(struct ath_softc *sc)
671 {
672 	int error;
673 	int i;
674 
675 	error = ath_descdma_alloc_desc(sc, &sc->sc_txsdma,
676 	    NULL, "txcomp", sc->sc_tx_statuslen, ATH_TXSTATUS_RING_SIZE);
677 	if (error != 0)
678 		return (error);
679 
680 	ath_hal_setuptxstatusring(sc->sc_ah,
681 	    (void *) sc->sc_txsdma.dd_desc,
682 	    sc->sc_txsdma.dd_desc_paddr,
683 	    ATH_TXSTATUS_RING_SIZE);
684 
685 	for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
686 		ath_edma_setup_txfifo(sc, i);
687 	}
688 
689 	return (0);
690 }
691 
692 static int
693 ath_edma_dma_txteardown(struct ath_softc *sc)
694 {
695 	int i;
696 
697 	for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
698 		ath_edma_free_txfifo(sc, i);
699 	}
700 
701 	ath_descdma_cleanup(sc, &sc->sc_txsdma, NULL);
702 	return (0);
703 }
704 
705 /*
706  * Drain all TXQs, potentially after completing the existing completed
707  * frames.
708  */
709 static void
710 ath_edma_tx_drain(struct ath_softc *sc, ATH_RESET_TYPE reset_type)
711 {
712 	int i;
713 
714 	DPRINTF(sc, ATH_DEBUG_RESET, "%s: called\n", __func__);
715 
716 	(void) ath_stoptxdma(sc);
717 
718 	/*
719 	 * If reset type is noloss, the TX FIFO needs to be serviced
720 	 * and those frames need to be handled.
721 	 *
722 	 * Otherwise, just toss everything in each TX queue.
723 	 */
724 	if (reset_type == ATH_RESET_NOLOSS) {
725 		ath_edma_tx_processq(sc, 0);
726 		for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
727 			if (ATH_TXQ_SETUP(sc, i)) {
728 				ATH_TXQ_LOCK(&sc->sc_txq[i]);
729 				/*
730 				 * Free the holding buffer; DMA is now
731 				 * stopped.
732 				 */
733 				ath_txq_freeholdingbuf(sc, &sc->sc_txq[i]);
734 				/*
735 				 * Reset the link pointer to NULL; there's
736 				 * no frames to chain DMA to.
737 				 */
738 				sc->sc_txq[i].axq_link = NULL;
739 				ATH_TXQ_UNLOCK(&sc->sc_txq[i]);
740 			}
741 		}
742 	} else {
743 		for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
744 			if (ATH_TXQ_SETUP(sc, i))
745 				ath_tx_draintxq(sc, &sc->sc_txq[i]);
746 		}
747 	}
748 
749 	/* XXX dump out the TX completion FIFO contents */
750 
751 	/* XXX dump out the frames */
752 
753 	sc->sc_wd_timer = 0;
754 }
755 
756 /*
757  * TX completion tasklet.
758  */
759 
760 static void
761 ath_edma_tx_proc(void *arg, int npending)
762 {
763 	struct ath_softc *sc = (struct ath_softc *) arg;
764 
765 	ATH_PCU_LOCK(sc);
766 	sc->sc_txproc_cnt++;
767 	ATH_PCU_UNLOCK(sc);
768 
769 	ATH_LOCK(sc);
770 	ath_power_set_power_state(sc, HAL_PM_AWAKE);
771 	ATH_UNLOCK(sc);
772 
773 #if 0
774 	DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: called, npending=%d\n",
775 	    __func__, npending);
776 #endif
777 	ath_edma_tx_processq(sc, 1);
778 
779 	ATH_PCU_LOCK(sc);
780 	sc->sc_txproc_cnt--;
781 	ATH_PCU_UNLOCK(sc);
782 
783 	ATH_LOCK(sc);
784 	ath_power_restore_power_state(sc);
785 	ATH_UNLOCK(sc);
786 
787 	ath_tx_kick(sc);
788 }
789 
790 /*
791  * Process the TX status queue.
792  */
793 static void
794 ath_edma_tx_processq(struct ath_softc *sc, int dosched)
795 {
796 	struct ath_hal *ah = sc->sc_ah;
797 	HAL_STATUS status;
798 	struct ath_tx_status ts;
799 	struct ath_txq *txq;
800 	struct ath_buf *bf;
801 	struct ieee80211_node *ni;
802 	int nacked = 0;
803 	int idx;
804 	int i;
805 
806 #ifdef	ATH_DEBUG
807 	/* XXX */
808 	uint32_t txstatus[32];
809 #endif
810 
811 	DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: called\n", __func__);
812 
813 	for (idx = 0; ; idx++) {
814 		bzero(&ts, sizeof(ts));
815 
816 		ATH_TXSTATUS_LOCK(sc);
817 #ifdef	ATH_DEBUG
818 		ath_hal_gettxrawtxdesc(ah, txstatus);
819 #endif
820 		status = ath_hal_txprocdesc(ah, NULL, (void *) &ts);
821 		ATH_TXSTATUS_UNLOCK(sc);
822 
823 		if (status == HAL_EINPROGRESS) {
824 			DPRINTF(sc, ATH_DEBUG_TX_PROC,
825 			    "%s: (%d): EINPROGRESS\n",
826 			    __func__, idx);
827 			break;
828 		}
829 
830 #ifdef	ATH_DEBUG
831 		if (sc->sc_debug & ATH_DEBUG_TX_PROC)
832 			if (ts.ts_queue_id != sc->sc_bhalq)
833 			ath_printtxstatbuf(sc, NULL, txstatus, ts.ts_queue_id,
834 			    idx, (status == HAL_OK));
835 #endif
836 
837 		/*
838 		 * If there is an error with this descriptor, continue
839 		 * processing.
840 		 *
841 		 * XXX TBD: log some statistics?
842 		 */
843 		if (status == HAL_EIO) {
844 			device_printf(sc->sc_dev, "%s: invalid TX status?\n",
845 			    __func__);
846 			break;
847 		}
848 
849 #if defined(ATH_DEBUG_ALQ) && defined(ATH_DEBUG)
850 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXSTATUS)) {
851 			if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_TXSTATUS,
852 			    sc->sc_tx_statuslen,
853 			    (char *) txstatus);
854 		}
855 #endif /* ATH_DEBUG_ALQ */
856 
857 		/*
858 		 * At this point we have a valid status descriptor.
859 		 * The QID and descriptor ID (which currently isn't set)
860 		 * is part of the status.
861 		 *
862 		 * We then assume that the descriptor in question is the
863 		 * -head- of the given QID.  Eventually we should verify
864 		 * this by using the descriptor ID.
865 		 */
866 
867 		/*
868 		 * The beacon queue is not currently a "real" queue.
869 		 * Frames aren't pushed onto it and the lock isn't setup.
870 		 * So skip it for now; the beacon handling code will
871 		 * free and alloc more beacon buffers as appropriate.
872 		 */
873 		if (ts.ts_queue_id == sc->sc_bhalq)
874 			continue;
875 
876 		txq = &sc->sc_txq[ts.ts_queue_id];
877 
878 		ATH_TXQ_LOCK(txq);
879 		bf = ATH_TXQ_FIRST(&txq->fifo);
880 
881 		/*
882 		 * Work around the situation where I'm seeing notifications
883 		 * for Q1 when no frames are available.  That needs to be
884 		 * debugged but not by crashing _here_.
885 		 */
886 		if (bf == NULL) {
887 			device_printf(sc->sc_dev, "%s: Q%d: empty?\n",
888 			    __func__,
889 			    ts.ts_queue_id);
890 			ATH_TXQ_UNLOCK(txq);
891 			continue;
892 		}
893 
894 		DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: Q%d, bf=%p, start=%d, end=%d\n",
895 		    __func__,
896 		    ts.ts_queue_id, bf,
897 		    !! (bf->bf_flags & ATH_BUF_FIFOPTR),
898 		    !! (bf->bf_flags & ATH_BUF_FIFOEND));
899 
900 		/* XXX TODO: actually output debugging info about this */
901 
902 #if 0
903 		/* XXX assert the buffer/descriptor matches the status descid */
904 		if (ts.ts_desc_id != bf->bf_descid) {
905 			device_printf(sc->sc_dev,
906 			    "%s: mismatched descid (qid=%d, tsdescid=%d, "
907 			    "bfdescid=%d\n",
908 			    __func__,
909 			    ts.ts_queue_id,
910 			    ts.ts_desc_id,
911 			    bf->bf_descid);
912 		}
913 #endif
914 
915 		/* This removes the buffer and decrements the queue depth */
916 		ATH_TXQ_REMOVE(&txq->fifo, bf, bf_list);
917 		if (bf->bf_state.bfs_aggr)
918 			txq->axq_aggr_depth--;
919 
920 		/*
921 		 * If this was the end of a FIFO set, decrement FIFO depth
922 		 */
923 		if (bf->bf_flags & ATH_BUF_FIFOEND)
924 			txq->axq_fifo_depth--;
925 
926 		/*
927 		 * If this isn't the final buffer in a FIFO set, mark
928 		 * the buffer as busy so it goes onto the holding queue.
929 		 */
930 		if (! (bf->bf_flags & ATH_BUF_FIFOEND))
931 			bf->bf_flags |= ATH_BUF_BUSY;
932 
933 		DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: Q%d: FIFO depth is now %d (%d)\n",
934 		    __func__,
935 		    txq->axq_qnum,
936 		    txq->axq_fifo_depth,
937 		    txq->fifo.axq_depth);
938 
939 		/* XXX assert FIFO depth >= 0 */
940 		ATH_TXQ_UNLOCK(txq);
941 
942 		/*
943 		 * Outside of the TX lock - if the buffer is end
944 		 * end buffer in this FIFO, we don't need a holding
945 		 * buffer any longer.
946 		 */
947 		if (bf->bf_flags & ATH_BUF_FIFOEND) {
948 			ATH_TXQ_LOCK(txq);
949 			ath_txq_freeholdingbuf(sc, txq);
950 			ATH_TXQ_UNLOCK(txq);
951 		}
952 
953 		/*
954 		 * First we need to make sure ts_rate is valid.
955 		 *
956 		 * Pre-EDMA chips pass the whole TX descriptor to
957 		 * the proctxdesc function which will then fill out
958 		 * ts_rate based on the ts_finaltsi (final TX index)
959 		 * in the TX descriptor.  However the TX completion
960 		 * FIFO doesn't have this information.  So here we
961 		 * do a separate HAL call to populate that information.
962 		 *
963 		 * The same problem exists with ts_longretry.
964 		 * The FreeBSD HAL corrects ts_longretry in the HAL layer;
965 		 * the AR9380 HAL currently doesn't.  So until the HAL
966 		 * is imported and this can be added, we correct for it
967 		 * here.
968 		 */
969 		/* XXX TODO */
970 		/* XXX faked for now. Ew. */
971 		if (ts.ts_finaltsi < 4) {
972 			ts.ts_rate =
973 			    bf->bf_state.bfs_rc[ts.ts_finaltsi].ratecode;
974 			switch (ts.ts_finaltsi) {
975 			case 3: ts.ts_longretry +=
976 			    bf->bf_state.bfs_rc[2].tries;
977 			case 2: ts.ts_longretry +=
978 			    bf->bf_state.bfs_rc[1].tries;
979 			case 1: ts.ts_longretry +=
980 			    bf->bf_state.bfs_rc[0].tries;
981 			}
982 		} else {
983 			device_printf(sc->sc_dev, "%s: finaltsi=%d\n",
984 			    __func__,
985 			    ts.ts_finaltsi);
986 			ts.ts_rate = bf->bf_state.bfs_rc[0].ratecode;
987 		}
988 
989 		/*
990 		 * XXX This is terrible.
991 		 *
992 		 * Right now, some code uses the TX status that is
993 		 * passed in here, but the completion handlers in the
994 		 * software TX path also use bf_status.ds_txstat.
995 		 * Ew.  That should all go away.
996 		 *
997 		 * XXX It's also possible the rate control completion
998 		 * routine is called twice.
999 		 */
1000 		memcpy(&bf->bf_status, &ts, sizeof(ts));
1001 
1002 		ni = bf->bf_node;
1003 
1004 		/* Update RSSI */
1005 		/* XXX duplicate from ath_tx_processq */
1006 		if (ni != NULL && ts.ts_status == 0 &&
1007 		    ((bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) == 0)) {
1008 			nacked++;
1009 			sc->sc_stats.ast_tx_rssi = ts.ts_rssi;
1010 			ATH_RSSI_LPF(sc->sc_halstats.ns_avgtxrssi,
1011 			    ts.ts_rssi);
1012 			ATH_RSSI_LPF(ATH_NODE(ni)->an_node_stats.ns_avgtxrssi,
1013 			    ts.ts_rssi);
1014 		}
1015 
1016 		/* Handle frame completion and rate control update */
1017 		ath_tx_process_buf_completion(sc, txq, &ts, bf);
1018 
1019 		/* NB: bf is invalid at this point */
1020 	}
1021 
1022 	sc->sc_wd_timer = 0;
1023 
1024 	/*
1025 	 * XXX It's inefficient to do this if the FIFO queue is full,
1026 	 * but there's no easy way right now to only populate
1027 	 * the txq task for _one_ TXQ.  This should be fixed.
1028 	 */
1029 	if (dosched) {
1030 		/* Attempt to schedule more hardware frames to the TX FIFO */
1031 		for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
1032 			if (ATH_TXQ_SETUP(sc, i)) {
1033 				ATH_TX_LOCK(sc);
1034 				ath_txq_sched(sc, &sc->sc_txq[i]);
1035 				ATH_TX_UNLOCK(sc);
1036 
1037 				ATH_TXQ_LOCK(&sc->sc_txq[i]);
1038 				ath_edma_tx_fifo_fill(sc, &sc->sc_txq[i]);
1039 				ATH_TXQ_UNLOCK(&sc->sc_txq[i]);
1040 			}
1041 		}
1042 		/* Kick software scheduler */
1043 		ath_tx_swq_kick(sc);
1044 	}
1045 
1046 	DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: end\n", __func__);
1047 }
1048 
1049 static void
1050 ath_edma_attach_comp_func(struct ath_softc *sc)
1051 {
1052 
1053 	TASK_INIT(&sc->sc_txtask, 0, ath_edma_tx_proc, sc);
1054 }
1055 
1056 void
1057 ath_xmit_setup_edma(struct ath_softc *sc)
1058 {
1059 
1060 	/* Fetch EDMA field and buffer sizes */
1061 	(void) ath_hal_gettxdesclen(sc->sc_ah, &sc->sc_tx_desclen);
1062 	(void) ath_hal_gettxstatuslen(sc->sc_ah, &sc->sc_tx_statuslen);
1063 	(void) ath_hal_getntxmaps(sc->sc_ah, &sc->sc_tx_nmaps);
1064 
1065 	if (bootverbose) {
1066 		device_printf(sc->sc_dev, "TX descriptor length: %d\n",
1067 		    sc->sc_tx_desclen);
1068 		device_printf(sc->sc_dev, "TX status length: %d\n",
1069 		    sc->sc_tx_statuslen);
1070 		device_printf(sc->sc_dev, "TX buffers per descriptor: %d\n",
1071 		    sc->sc_tx_nmaps);
1072 	}
1073 
1074 	sc->sc_tx.xmit_setup = ath_edma_dma_txsetup;
1075 	sc->sc_tx.xmit_teardown = ath_edma_dma_txteardown;
1076 	sc->sc_tx.xmit_attach_comp_func = ath_edma_attach_comp_func;
1077 
1078 	sc->sc_tx.xmit_dma_restart = ath_edma_dma_restart;
1079 	sc->sc_tx.xmit_handoff = ath_edma_xmit_handoff;
1080 	sc->sc_tx.xmit_drain = ath_edma_tx_drain;
1081 }
1082