xref: /freebsd/sys/dev/ath/if_ath_tx_edma.c (revision 197186496661d8f63639b5b27b33851f727d4da7)
1 /*-
2  * Copyright (c) 2012 Adrian Chadd <adrian@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer,
10  *    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.
15  *
16  * NO WARRANTY
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.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
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_dl.h>
77 #include <net/if_media.h>
78 #include <net/if_types.h>
79 #include <net/if_arp.h>
80 #include <net/ethernet.h>
81 #include <net/if_llc.h>
82 
83 #include <net80211/ieee80211_var.h>
84 #include <net80211/ieee80211_regdomain.h>
85 #ifdef IEEE80211_SUPPORT_SUPERG
86 #include <net80211/ieee80211_superg.h>
87 #endif
88 #ifdef IEEE80211_SUPPORT_TDMA
89 #include <net80211/ieee80211_tdma.h>
90 #endif
91 
92 #include <net/bpf.h>
93 
94 #ifdef INET
95 #include <netinet/in.h>
96 #include <netinet/if_ether.h>
97 #endif
98 
99 #include <dev/ath/if_athvar.h>
100 #include <dev/ath/ath_hal/ah_devid.h>		/* XXX for softled */
101 #include <dev/ath/ath_hal/ah_diagcodes.h>
102 
103 #include <dev/ath/if_ath_debug.h>
104 #include <dev/ath/if_ath_misc.h>
105 #include <dev/ath/if_ath_tsf.h>
106 #include <dev/ath/if_ath_tx.h>
107 #include <dev/ath/if_ath_sysctl.h>
108 #include <dev/ath/if_ath_led.h>
109 #include <dev/ath/if_ath_keycache.h>
110 #include <dev/ath/if_ath_rx.h>
111 #include <dev/ath/if_ath_beacon.h>
112 #include <dev/ath/if_athdfs.h>
113 
114 #ifdef ATH_TX99_DIAG
115 #include <dev/ath/ath_tx99/ath_tx99.h>
116 #endif
117 
118 #include <dev/ath/if_ath_tx_edma.h>
119 
120 #ifdef	ATH_DEBUG_ALQ
121 #include <dev/ath/if_ath_alq.h>
122 #endif
123 
124 /*
125  * some general macros
126  */
127 #define	INCR(_l, _sz)		(_l) ++; (_l) &= ((_sz) - 1)
128 #define	DECR(_l, _sz)		(_l) --; (_l) &= ((_sz) - 1)
129 
130 /*
131  * XXX doesn't belong here, and should be tunable
132  */
133 #define	ATH_TXSTATUS_RING_SIZE	512
134 
135 MALLOC_DECLARE(M_ATHDEV);
136 
137 static void ath_edma_tx_processq(struct ath_softc *sc, int dosched);
138 
139 static void
140 ath_edma_tx_fifo_fill(struct ath_softc *sc, struct ath_txq *txq)
141 {
142 	struct ath_buf *bf;
143 	int i = 0;
144 
145 	ATH_TX_LOCK_ASSERT(sc);
146 
147 	DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: called\n", __func__);
148 
149 	TAILQ_FOREACH(bf, &txq->axq_q, bf_list) {
150 		if (txq->axq_fifo_depth >= HAL_TXFIFO_DEPTH)
151 			break;
152 		ath_hal_puttxbuf(sc->sc_ah, txq->axq_qnum, bf->bf_daddr);
153 #ifdef	ATH_DEBUG
154 		if (sc->sc_debug & ATH_DEBUG_XMIT_DESC)
155 			ath_printtxbuf(sc, bf, txq->axq_qnum, i, 0);
156 #endif/* ATH_DEBUG */
157 #ifdef	ATH_DEBUG_ALQ
158 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
159 			ath_tx_alq_post(sc, bf);
160 #endif /* ATH_DEBUG_ALQ */
161 		txq->axq_fifo_depth++;
162 		i++;
163 	}
164 	if (i > 0)
165 		ath_hal_txstart(sc->sc_ah, txq->axq_qnum);
166 }
167 
168 /*
169  * Re-initialise the DMA FIFO with the current contents of
170  * said TXQ.
171  *
172  * This should only be called as part of the chip reset path, as it
173  * assumes the FIFO is currently empty.
174  */
175 static void
176 ath_edma_dma_restart(struct ath_softc *sc, struct ath_txq *txq)
177 {
178 
179 	DPRINTF(sc, ATH_DEBUG_RESET, "%s: called: txq=%p, qnum=%d\n",
180 	    __func__,
181 	    txq,
182 	    txq->axq_qnum);
183 
184 	ATH_TX_LOCK_ASSERT(sc);
185 	ath_edma_tx_fifo_fill(sc, txq);
186 
187 }
188 
189 /*
190  * Hand off this frame to a hardware queue.
191  *
192  * Things are a bit hairy in the EDMA world.  The TX FIFO is only
193  * 8 entries deep, so we need to keep track of exactly what we've
194  * pushed into the FIFO and what's just sitting in the TX queue,
195  * waiting to go out.
196  *
197  * So this is split into two halves - frames get appended to the
198  * TXQ; then a scheduler is called to push some frames into the
199  * actual TX FIFO.
200  */
201 static void
202 ath_edma_xmit_handoff_hw(struct ath_softc *sc, struct ath_txq *txq,
203     struct ath_buf *bf)
204 {
205 	struct ath_hal *ah = sc->sc_ah;
206 
207 	ATH_TX_LOCK_ASSERT(sc);
208 
209 	KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
210 	    ("%s: busy status 0x%x", __func__, bf->bf_flags));
211 
212 	/*
213 	 * XXX TODO: write a hard-coded check to ensure that
214 	 * the queue id in the TX descriptor matches txq->axq_qnum.
215 	 */
216 
217 	/* Update aggr stats */
218 	if (bf->bf_state.bfs_aggr)
219 		txq->axq_aggr_depth++;
220 
221 	/* Push and update frame stats */
222 	ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
223 
224 	/* Only schedule to the FIFO if there's space */
225 	if (txq->axq_fifo_depth < HAL_TXFIFO_DEPTH) {
226 #ifdef	ATH_DEBUG
227 		if (sc->sc_debug & ATH_DEBUG_XMIT_DESC)
228 			ath_printtxbuf(sc, bf, txq->axq_qnum, 0, 0);
229 #endif /* ATH_DEBUG */
230 #ifdef	ATH_DEBUG_ALQ
231 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
232 			ath_tx_alq_post(sc, bf);
233 #endif	/* ATH_DEBUG_ALQ */
234 		ath_hal_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
235 		txq->axq_fifo_depth++;
236 		ath_hal_txstart(ah, txq->axq_qnum);
237 	}
238 }
239 
240 /*
241  * Hand off this frame to a multicast software queue.
242  *
243  * The EDMA TX CABQ will get a list of chained frames, chained
244  * together using the next pointer.  The single head of that
245  * particular queue is pushed to the hardware CABQ.
246  */
247 static void
248 ath_edma_xmit_handoff_mcast(struct ath_softc *sc, struct ath_txq *txq,
249     struct ath_buf *bf)
250 {
251 
252 	ATH_TX_LOCK_ASSERT(sc);
253 	KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
254 	    ("%s: busy status 0x%x", __func__, bf->bf_flags));
255 
256 	/*
257 	 * XXX this is mostly duplicated in ath_tx_handoff_mcast().
258 	 */
259 	if (ATH_TXQ_FIRST(txq) != NULL) {
260 		struct ath_buf *bf_last = ATH_TXQ_LAST(txq, axq_q_s);
261 		struct ieee80211_frame *wh;
262 
263 		/* mark previous frame */
264 		wh = mtod(bf_last->bf_m, struct ieee80211_frame *);
265 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
266 
267 		/* sync descriptor to memory */
268 		bus_dmamap_sync(sc->sc_dmat, bf_last->bf_dmamap,
269 		   BUS_DMASYNC_PREWRITE);
270 	}
271 
272 #ifdef	ATH_DEBUG_ALQ
273 	if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXDESC))
274 		ath_tx_alq_post(sc, bf);
275 #endif	/* ATH_DEBUG_ALQ */
276 
277 	ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
278 	ath_hal_gettxdesclinkptr(sc->sc_ah, bf->bf_lastds, &txq->axq_link);
279 }
280 
281 /*
282  * Handoff this frame to the hardware.
283  *
284  * For the multicast queue, this will treat it as a software queue
285  * and append it to the list, after updating the MORE_DATA flag
286  * in the previous frame.  The cabq processing code will ensure
287  * that the queue contents gets transferred over.
288  *
289  * For the hardware queues, this will queue a frame to the queue
290  * like before, then populate the FIFO from that.  Since the
291  * EDMA hardware has 8 FIFO slots per TXQ, this ensures that
292  * frames such as management frames don't get prematurely dropped.
293  *
294  * This does imply that a similar flush-hwq-to-fifoq method will
295  * need to be called from the processq function, before the
296  * per-node software scheduler is called.
297  */
298 static void
299 ath_edma_xmit_handoff(struct ath_softc *sc, struct ath_txq *txq,
300     struct ath_buf *bf)
301 {
302 
303 	ATH_TX_LOCK_ASSERT(sc);
304 
305 	DPRINTF(sc, ATH_DEBUG_XMIT_DESC,
306 	    "%s: called; bf=%p, txq=%p, qnum=%d\n",
307 	    __func__,
308 	    bf,
309 	    txq,
310 	    txq->axq_qnum);
311 
312 	if (txq->axq_qnum == ATH_TXQ_SWQ)
313 		ath_edma_xmit_handoff_mcast(sc, txq, bf);
314 	else
315 		ath_edma_xmit_handoff_hw(sc, txq, bf);
316 
317 #if 0
318 	/*
319 	 * XXX For now this is a placeholder; free the buffer
320 	 * and inform the stack that the TX failed.
321 	 */
322 	ath_tx_default_comp(sc, bf, 1);
323 #endif
324 }
325 
326 static int
327 ath_edma_setup_txfifo(struct ath_softc *sc, int qnum)
328 {
329 	struct ath_tx_edma_fifo *te = &sc->sc_txedma[qnum];
330 
331 	te->m_fifo = malloc(sizeof(struct ath_buf *) * HAL_TXFIFO_DEPTH,
332 	    M_ATHDEV,
333 	    M_NOWAIT | M_ZERO);
334 	if (te->m_fifo == NULL) {
335 		device_printf(sc->sc_dev, "%s: malloc failed\n",
336 		    __func__);
337 		return (-ENOMEM);
338 	}
339 
340 	/*
341 	 * Set initial "empty" state.
342 	 */
343 	te->m_fifo_head = te->m_fifo_tail = te->m_fifo_depth = 0;
344 
345 	return (0);
346 }
347 
348 static int
349 ath_edma_free_txfifo(struct ath_softc *sc, int qnum)
350 {
351 	struct ath_tx_edma_fifo *te = &sc->sc_txedma[qnum];
352 
353 	/* XXX TODO: actually deref the ath_buf entries? */
354 	free(te->m_fifo, M_ATHDEV);
355 	return (0);
356 }
357 
358 static int
359 ath_edma_dma_txsetup(struct ath_softc *sc)
360 {
361 	int error;
362 	int i;
363 
364 	error = ath_descdma_alloc_desc(sc, &sc->sc_txsdma,
365 	    NULL, "txcomp", sc->sc_tx_statuslen, ATH_TXSTATUS_RING_SIZE);
366 	if (error != 0)
367 		return (error);
368 
369 	ath_hal_setuptxstatusring(sc->sc_ah,
370 	    (void *) sc->sc_txsdma.dd_desc,
371 	    sc->sc_txsdma.dd_desc_paddr,
372 	    ATH_TXSTATUS_RING_SIZE);
373 
374 	for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
375 		ath_edma_setup_txfifo(sc, i);
376 	}
377 
378 	return (0);
379 }
380 
381 static int
382 ath_edma_dma_txteardown(struct ath_softc *sc)
383 {
384 	int i;
385 
386 	for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
387 		ath_edma_free_txfifo(sc, i);
388 	}
389 
390 	ath_descdma_cleanup(sc, &sc->sc_txsdma, NULL);
391 	return (0);
392 }
393 
394 /*
395  * Drain all TXQs, potentially after completing the existing completed
396  * frames.
397  */
398 static void
399 ath_edma_tx_drain(struct ath_softc *sc, ATH_RESET_TYPE reset_type)
400 {
401 	struct ifnet *ifp = sc->sc_ifp;
402 	int i;
403 
404 	DPRINTF(sc, ATH_DEBUG_RESET, "%s: called\n", __func__);
405 
406 	(void) ath_stoptxdma(sc);
407 
408 	/*
409 	 * If reset type is noloss, the TX FIFO needs to be serviced
410 	 * and those frames need to be handled.
411 	 *
412 	 * Otherwise, just toss everything in each TX queue.
413 	 */
414 	if (reset_type == ATH_RESET_NOLOSS) {
415 		ath_edma_tx_processq(sc, 0);
416 	} else {
417 		for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
418 			if (ATH_TXQ_SETUP(sc, i))
419 				ath_tx_draintxq(sc, &sc->sc_txq[i]);
420 		}
421 	}
422 
423 	/* XXX dump out the TX completion FIFO contents */
424 
425 	/* XXX dump out the frames */
426 
427 	IF_LOCK(&ifp->if_snd);
428 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
429 	IF_UNLOCK(&ifp->if_snd);
430 	sc->sc_wd_timer = 0;
431 }
432 
433 /*
434  * TX completion tasklet.
435  */
436 
437 static void
438 ath_edma_tx_proc(void *arg, int npending)
439 {
440 	struct ath_softc *sc = (struct ath_softc *) arg;
441 
442 	DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: called, npending=%d\n",
443 	    __func__, npending);
444 	ath_edma_tx_processq(sc, 1);
445 }
446 
447 /*
448  * Process the TX status queue.
449  */
450 static void
451 ath_edma_tx_processq(struct ath_softc *sc, int dosched)
452 {
453 	struct ath_hal *ah = sc->sc_ah;
454 	HAL_STATUS status;
455 	struct ath_tx_status ts;
456 	struct ath_txq *txq;
457 	struct ath_buf *bf;
458 	struct ieee80211_node *ni;
459 	int nacked = 0;
460 	int idx;
461 
462 #ifdef	ATH_DEBUG
463 	/* XXX */
464 	uint32_t txstatus[32];
465 #endif
466 
467 	for (idx = 0; ; idx++) {
468 		bzero(&ts, sizeof(ts));
469 
470 		ATH_TXSTATUS_LOCK(sc);
471 #ifdef	ATH_DEBUG
472 		ath_hal_gettxrawtxdesc(ah, txstatus);
473 #endif
474 		status = ath_hal_txprocdesc(ah, NULL, (void *) &ts);
475 		ATH_TXSTATUS_UNLOCK(sc);
476 
477 #ifdef	ATH_DEBUG
478 		if (sc->sc_debug & ATH_DEBUG_TX_PROC)
479 			ath_printtxstatbuf(sc, NULL, txstatus, ts.ts_queue_id,
480 			    idx, (status == HAL_OK));
481 #endif
482 
483 		if (status == HAL_EINPROGRESS)
484 			break;
485 
486 		/*
487 		 * If there is an error with this descriptor, continue
488 		 * processing.
489 		 *
490 		 * XXX TBD: log some statistics?
491 		 */
492 		if (status == HAL_EIO) {
493 			device_printf(sc->sc_dev, "%s: invalid TX status?\n",
494 			    __func__);
495 			continue;
496 		}
497 
498 #ifdef	ATH_DEBUG_ALQ
499 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_TXSTATUS))
500 			if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_TXSTATUS,
501 			    sc->sc_tx_statuslen,
502 			    (char *) txstatus);
503 #endif /* ATH_DEBUG_ALQ */
504 
505 		/*
506 		 * At this point we have a valid status descriptor.
507 		 * The QID and descriptor ID (which currently isn't set)
508 		 * is part of the status.
509 		 *
510 		 * We then assume that the descriptor in question is the
511 		 * -head- of the given QID.  Eventually we should verify
512 		 * this by using the descriptor ID.
513 		 */
514 
515 		/*
516 		 * The beacon queue is not currently a "real" queue.
517 		 * Frames aren't pushed onto it and the lock isn't setup.
518 		 * So skip it for now; the beacon handling code will
519 		 * free and alloc more beacon buffers as appropriate.
520 		 */
521 		if (ts.ts_queue_id == sc->sc_bhalq)
522 			continue;
523 
524 		txq = &sc->sc_txq[ts.ts_queue_id];
525 
526 		ATH_TX_LOCK(sc);
527 		bf = TAILQ_FIRST(&txq->axq_q);
528 
529 		DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: qcuid=%d, bf=%p\n",
530 		    __func__,
531 		    ts.ts_queue_id, bf);
532 
533 		/* XXX TODO: actually output debugging info about this */
534 
535 #if 0
536 		/* XXX assert the buffer/descriptor matches the status descid */
537 		if (ts.ts_desc_id != bf->bf_descid) {
538 			device_printf(sc->sc_dev,
539 			    "%s: mismatched descid (qid=%d, tsdescid=%d, "
540 			    "bfdescid=%d\n",
541 			    __func__,
542 			    ts.ts_queue_id,
543 			    ts.ts_desc_id,
544 			    bf->bf_descid);
545 		}
546 #endif
547 
548 		/* This removes the buffer and decrements the queue depth */
549 		ATH_TXQ_REMOVE(txq, bf, bf_list);
550 		if (bf->bf_state.bfs_aggr)
551 			txq->axq_aggr_depth--;
552 		txq->axq_fifo_depth --;
553 		/* XXX assert FIFO depth >= 0 */
554 		ATH_TX_UNLOCK(sc);
555 
556 		/*
557 		 * First we need to make sure ts_rate is valid.
558 		 *
559 		 * Pre-EDMA chips pass the whole TX descriptor to
560 		 * the proctxdesc function which will then fill out
561 		 * ts_rate based on the ts_finaltsi (final TX index)
562 		 * in the TX descriptor.  However the TX completion
563 		 * FIFO doesn't have this information.  So here we
564 		 * do a separate HAL call to populate that information.
565 		 *
566 		 * The same problem exists with ts_longretry.
567 		 * The FreeBSD HAL corrects ts_longretry in the HAL layer;
568 		 * the AR9380 HAL currently doesn't.  So until the HAL
569 		 * is imported and this can be added, we correct for it
570 		 * here.
571 		 */
572 		/* XXX TODO */
573 		/* XXX faked for now. Ew. */
574 		if (ts.ts_finaltsi < 4) {
575 			ts.ts_rate =
576 			    bf->bf_state.bfs_rc[ts.ts_finaltsi].ratecode;
577 			switch (ts.ts_finaltsi) {
578 			case 3: ts.ts_longretry +=
579 			    bf->bf_state.bfs_rc[2].tries;
580 			case 2: ts.ts_longretry +=
581 			    bf->bf_state.bfs_rc[1].tries;
582 			case 1: ts.ts_longretry +=
583 			    bf->bf_state.bfs_rc[0].tries;
584 			}
585 		} else {
586 			device_printf(sc->sc_dev, "%s: finaltsi=%d\n",
587 			    __func__,
588 			    ts.ts_finaltsi);
589 			ts.ts_rate = bf->bf_state.bfs_rc[0].ratecode;
590 		}
591 
592 		/*
593 		 * XXX This is terrible.
594 		 *
595 		 * Right now, some code uses the TX status that is
596 		 * passed in here, but the completion handlers in the
597 		 * software TX path also use bf_status.ds_txstat.
598 		 * Ew.  That should all go away.
599 		 *
600 		 * XXX It's also possible the rate control completion
601 		 * routine is called twice.
602 		 */
603 		memcpy(&bf->bf_status, &ts, sizeof(ts));
604 
605 		ni = bf->bf_node;
606 
607 		/* Update RSSI */
608 		/* XXX duplicate from ath_tx_processq */
609 		if (ni != NULL && ts.ts_status == 0 &&
610 		    ((bf->bf_state.bfs_txflags & HAL_TXDESC_NOACK) == 0)) {
611 			nacked++;
612 			sc->sc_stats.ast_tx_rssi = ts.ts_rssi;
613 			ATH_RSSI_LPF(sc->sc_halstats.ns_avgtxrssi,
614 			    ts.ts_rssi);
615 		}
616 
617 		/* Handle frame completion and rate control update */
618 		ath_tx_process_buf_completion(sc, txq, &ts, bf);
619 
620 		/* bf is invalid at this point */
621 
622 		/*
623 		 * Now that there's space in the FIFO, let's push some
624 		 * more frames into it.
625 		 *
626 		 * Unfortunately for now, the txq has FIFO and non-FIFO
627 		 * frames in the same linked list, so there's no way
628 		 * to quickly/easily populate frames without walking
629 		 * the queue and skipping 'axq_fifo_depth' frames.
630 		 *
631 		 * So for now, let's only repopulate the FIFO once it
632 		 * is empty.  It's sucky for performance but it's enough
633 		 * to begin validating that things are somewhat
634 		 * working.
635 		 */
636 		ATH_TX_LOCK(sc);
637 		if (dosched && txq->axq_fifo_depth == 0) {
638 			ath_edma_tx_fifo_fill(sc, txq);
639 		}
640 		ATH_TX_UNLOCK(sc);
641 	}
642 
643 	sc->sc_wd_timer = 0;
644 
645 	if (idx > 0) {
646 		IF_LOCK(&sc->sc_ifp->if_snd);
647 		sc->sc_ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
648 		IF_UNLOCK(&sc->sc_ifp->if_snd);
649 	}
650 
651 	/* Kick software scheduler */
652 	/*
653 	 * XXX It's inefficient to do this if the FIFO queue is full,
654 	 * but there's no easy way right now to only populate
655 	 * the txq task for _one_ TXQ.  This should be fixed.
656 	 */
657 	if (dosched)
658 		taskqueue_enqueue(sc->sc_tq, &sc->sc_txqtask);
659 }
660 
661 static void
662 ath_edma_attach_comp_func(struct ath_softc *sc)
663 {
664 
665 	TASK_INIT(&sc->sc_txtask, 0, ath_edma_tx_proc, sc);
666 }
667 
668 void
669 ath_xmit_setup_edma(struct ath_softc *sc)
670 {
671 
672 	/* Fetch EDMA field and buffer sizes */
673 	(void) ath_hal_gettxdesclen(sc->sc_ah, &sc->sc_tx_desclen);
674 	(void) ath_hal_gettxstatuslen(sc->sc_ah, &sc->sc_tx_statuslen);
675 	(void) ath_hal_getntxmaps(sc->sc_ah, &sc->sc_tx_nmaps);
676 
677 	device_printf(sc->sc_dev, "TX descriptor length: %d\n",
678 	    sc->sc_tx_desclen);
679 	device_printf(sc->sc_dev, "TX status length: %d\n",
680 	    sc->sc_tx_statuslen);
681 	device_printf(sc->sc_dev, "TX buffers per descriptor: %d\n",
682 	    sc->sc_tx_nmaps);
683 
684 	sc->sc_tx.xmit_setup = ath_edma_dma_txsetup;
685 	sc->sc_tx.xmit_teardown = ath_edma_dma_txteardown;
686 	sc->sc_tx.xmit_attach_comp_func = ath_edma_attach_comp_func;
687 
688 	sc->sc_tx.xmit_dma_restart = ath_edma_dma_restart;
689 	sc->sc_tx.xmit_handoff = ath_edma_xmit_handoff;
690 	sc->sc_tx.xmit_drain = ath_edma_tx_drain;
691 }
692