xref: /freebsd/sys/dev/ath/if_ath_rx_edma.c (revision ce3adf4362fcca6a43e500b2531f0038adbfbd21)
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_rx_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 MALLOC_DECLARE(M_ATHDEV);
131 
132 /*
133  * XXX TODO:
134  *
135  * + Make sure the FIFO is correctly flushed and reinitialised
136  *   through a reset;
137  * + Verify multi-descriptor frames work!
138  * + There's a "memory use after free" which needs to be tracked down
139  *   and fixed ASAP.  I've seen this in the legacy path too, so it
140  *   may be a generic RX path issue.
141  */
142 
143 /*
144  * XXX shuffle the function orders so these pre-declarations aren't
145  * required!
146  */
147 static	int ath_edma_rxfifo_alloc(struct ath_softc *sc, HAL_RX_QUEUE qtype,
148 	    int nbufs);
149 static	int ath_edma_rxfifo_flush(struct ath_softc *sc, HAL_RX_QUEUE qtype);
150 static	void ath_edma_rxbuf_free(struct ath_softc *sc, struct ath_buf *bf);
151 static	void ath_edma_recv_proc_queue(struct ath_softc *sc,
152 	    HAL_RX_QUEUE qtype, int dosched);
153 static	int ath_edma_recv_proc_deferred_queue(struct ath_softc *sc,
154 	    HAL_RX_QUEUE qtype, int dosched);
155 
156 static void
157 ath_edma_stoprecv(struct ath_softc *sc, int dodelay)
158 {
159 	struct ath_hal *ah = sc->sc_ah;
160 
161 	ATH_RX_LOCK(sc);
162 	ath_hal_stoppcurecv(ah);
163 	ath_hal_setrxfilter(ah, 0);
164 	ath_hal_stopdmarecv(ah);
165 
166 	DELAY(3000);
167 
168 	/* Flush RX pending for each queue */
169 	/* XXX should generic-ify this */
170 	if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending) {
171 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending);
172 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending = NULL;
173 	}
174 
175 	if (sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending) {
176 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending);
177 		sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending = NULL;
178 	}
179 	ATH_RX_UNLOCK(sc);
180 }
181 
182 /*
183  * Re-initialise the FIFO given the current buffer contents.
184  * Specifically, walk from head -> tail, pushing the FIFO contents
185  * back into the FIFO.
186  */
187 static void
188 ath_edma_reinit_fifo(struct ath_softc *sc, HAL_RX_QUEUE qtype)
189 {
190 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
191 	struct ath_buf *bf;
192 	int i, j;
193 
194 	ATH_RX_LOCK_ASSERT(sc);
195 
196 	i = re->m_fifo_head;
197 	for (j = 0; j < re->m_fifo_depth; j++) {
198 		bf = re->m_fifo[i];
199 		DPRINTF(sc, ATH_DEBUG_EDMA_RX,
200 		    "%s: Q%d: pos=%i, addr=0x%jx\n",
201 		    __func__,
202 		    qtype,
203 		    i,
204 		    (uintmax_t)bf->bf_daddr);
205 		ath_hal_putrxbuf(sc->sc_ah, bf->bf_daddr, qtype);
206 		INCR(i, re->m_fifolen);
207 	}
208 
209 	/* Ensure this worked out right */
210 	if (i != re->m_fifo_tail) {
211 		device_printf(sc->sc_dev, "%s: i (%d) != tail! (%d)\n",
212 		    __func__,
213 		    i,
214 		    re->m_fifo_tail);
215 	}
216 }
217 
218 /*
219  * Start receive.
220  *
221  * XXX TODO: this needs to reallocate the FIFO entries when a reset
222  * occurs, in case the FIFO is filled up and no new descriptors get
223  * thrown into the FIFO.
224  */
225 static int
226 ath_edma_startrecv(struct ath_softc *sc)
227 {
228 	struct ath_hal *ah = sc->sc_ah;
229 
230 	ATH_RX_LOCK(sc);
231 
232 	/* Enable RX FIFO */
233 	ath_hal_rxena(ah);
234 
235 	/*
236 	 * Entries should only be written out if the
237 	 * FIFO is empty.
238 	 *
239 	 * XXX This isn't correct. I should be looking
240 	 * at the value of AR_RXDP_SIZE (0x0070) to determine
241 	 * how many entries are in here.
242 	 *
243 	 * A warm reset will clear the registers but not the FIFO.
244 	 *
245 	 * And I believe this is actually the address of the last
246 	 * handled buffer rather than the current FIFO pointer.
247 	 * So if no frames have been (yet) seen, we'll reinit the
248 	 * FIFO.
249 	 *
250 	 * I'll chase that up at some point.
251 	 */
252 	if (ath_hal_getrxbuf(sc->sc_ah, HAL_RX_QUEUE_HP) == 0) {
253 		DPRINTF(sc, ATH_DEBUG_EDMA_RX,
254 		    "%s: Re-initing HP FIFO\n", __func__);
255 		ath_edma_reinit_fifo(sc, HAL_RX_QUEUE_HP);
256 	}
257 	if (ath_hal_getrxbuf(sc->sc_ah, HAL_RX_QUEUE_LP) == 0) {
258 		DPRINTF(sc, ATH_DEBUG_EDMA_RX,
259 		    "%s: Re-initing LP FIFO\n", __func__);
260 		ath_edma_reinit_fifo(sc, HAL_RX_QUEUE_LP);
261 	}
262 
263 	/* Add up to m_fifolen entries in each queue */
264 	/*
265 	 * These must occur after the above write so the FIFO buffers
266 	 * are pushed/tracked in the same order as the hardware will
267 	 * process them.
268 	 */
269 	ath_edma_rxfifo_alloc(sc, HAL_RX_QUEUE_HP,
270 	    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_fifolen);
271 
272 	ath_edma_rxfifo_alloc(sc, HAL_RX_QUEUE_LP,
273 	    sc->sc_rxedma[HAL_RX_QUEUE_LP].m_fifolen);
274 
275 	ath_mode_init(sc);
276 	ath_hal_startpcurecv(ah);
277 
278 	ATH_RX_UNLOCK(sc);
279 
280 	return (0);
281 }
282 
283 static void
284 ath_edma_recv_sched_queue(struct ath_softc *sc, HAL_RX_QUEUE qtype,
285     int dosched)
286 {
287 
288 	ath_edma_recv_proc_queue(sc, qtype, dosched);
289 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
290 }
291 
292 static void
293 ath_edma_recv_sched(struct ath_softc *sc, int dosched)
294 {
295 
296 	ath_edma_recv_proc_queue(sc, HAL_RX_QUEUE_HP, dosched);
297 	ath_edma_recv_proc_queue(sc, HAL_RX_QUEUE_LP, dosched);
298 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
299 }
300 
301 static void
302 ath_edma_recv_flush(struct ath_softc *sc)
303 {
304 
305 	DPRINTF(sc, ATH_DEBUG_RECV, "%s: called\n", __func__);
306 
307 	ATH_PCU_LOCK(sc);
308 	sc->sc_rxproc_cnt++;
309 	ATH_PCU_UNLOCK(sc);
310 
311 	/*
312 	 * Flush any active frames from FIFO -> deferred list
313 	 */
314 	ath_edma_recv_proc_queue(sc, HAL_RX_QUEUE_HP, 0);
315 	ath_edma_recv_proc_queue(sc, HAL_RX_QUEUE_LP, 0);
316 
317 	/*
318 	 * Process what's in the deferred queue
319 	 */
320 	ath_edma_recv_proc_deferred_queue(sc, HAL_RX_QUEUE_HP, 0);
321 	ath_edma_recv_proc_deferred_queue(sc, HAL_RX_QUEUE_LP, 0);
322 
323 	ATH_PCU_LOCK(sc);
324 	sc->sc_rxproc_cnt--;
325 	ATH_PCU_UNLOCK(sc);
326 }
327 
328 /*
329  * Process frames from the current queue into the deferred queue.
330  */
331 static void
332 ath_edma_recv_proc_queue(struct ath_softc *sc, HAL_RX_QUEUE qtype,
333     int dosched)
334 {
335 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
336 	struct ath_rx_status *rs;
337 	struct ath_desc *ds;
338 	struct ath_buf *bf;
339 	struct mbuf *m;
340 	struct ath_hal *ah = sc->sc_ah;
341 	uint64_t tsf;
342 	uint16_t nf;
343 	int npkts = 0;
344 
345 	tsf = ath_hal_gettsf64(ah);
346 	nf = ath_hal_getchannoise(ah, sc->sc_curchan);
347 	sc->sc_stats.ast_rx_noise = nf;
348 
349 	ATH_RX_LOCK(sc);
350 
351 	do {
352 		bf = re->m_fifo[re->m_fifo_head];
353 		/* This shouldn't occur! */
354 		if (bf == NULL) {
355 			device_printf(sc->sc_dev, "%s: Q%d: NULL bf?\n",
356 			    __func__,
357 			    qtype);
358 			break;
359 		}
360 		m = bf->bf_m;
361 		ds = bf->bf_desc;
362 
363 		/*
364 		 * Sync descriptor memory - this also syncs the buffer for us.
365 		 * EDMA descriptors are in cached memory.
366 		 */
367 		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
368 		    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
369 		rs = &bf->bf_status.ds_rxstat;
370 		bf->bf_rxstatus = ath_hal_rxprocdesc(ah, ds, bf->bf_daddr,
371 		    NULL, rs);
372 #ifdef	ATH_DEBUG
373 		if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
374 			ath_printrxbuf(sc, bf, 0, bf->bf_rxstatus == HAL_OK);
375 #endif /* ATH_DEBUG */
376 #ifdef	ATH_DEBUG_ALQ
377 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS))
378 			if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS,
379 			    sc->sc_rx_statuslen, (char *) ds);
380 #endif /* ATH_DEBUG */
381 		if (bf->bf_rxstatus == HAL_EINPROGRESS)
382 			break;
383 
384 		/*
385 		 * Completed descriptor.
386 		 */
387 		DPRINTF(sc, ATH_DEBUG_EDMA_RX,
388 		    "%s: Q%d: completed!\n", __func__, qtype);
389 		npkts++;
390 
391 		/*
392 		 * We've been synced already, so unmap.
393 		 */
394 		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
395 
396 		/*
397 		 * Remove the FIFO entry and place it on the completion
398 		 * queue.
399 		 */
400 		re->m_fifo[re->m_fifo_head] = NULL;
401 		TAILQ_INSERT_TAIL(&sc->sc_rx_rxlist[qtype], bf, bf_list);
402 
403 		/* Bump the descriptor FIFO stats */
404 		INCR(re->m_fifo_head, re->m_fifolen);
405 		re->m_fifo_depth--;
406 		/* XXX check it doesn't fall below 0 */
407 	} while (re->m_fifo_depth > 0);
408 
409 	/* Append some more fresh frames to the FIFO */
410 	if (dosched)
411 		ath_edma_rxfifo_alloc(sc, qtype, re->m_fifolen);
412 
413 	ATH_RX_UNLOCK(sc);
414 
415 	/* rx signal state monitoring */
416 	ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
417 
418 	ATH_KTR(sc, ATH_KTR_INTERRUPTS, 1,
419 	    "ath edma rx proc: npkts=%d\n",
420 	    npkts);
421 
422 	/* Handle resched and kickpcu appropriately */
423 	ATH_PCU_LOCK(sc);
424 	if (dosched && sc->sc_kickpcu) {
425 		ATH_KTR(sc, ATH_KTR_ERROR, 0,
426 		    "ath_edma_recv_proc_queue(): kickpcu");
427 		if (npkts > 0)
428 			device_printf(sc->sc_dev,
429 			    "%s: handled npkts %d\n",
430 			    __func__, npkts);
431 
432 		/*
433 		 * XXX TODO: what should occur here? Just re-poke and
434 		 * re-enable the RX FIFO?
435 		 */
436 		sc->sc_kickpcu = 0;
437 	}
438 	ATH_PCU_UNLOCK(sc);
439 
440 	return;
441 }
442 
443 /*
444  * Flush the deferred queue.
445  *
446  * This destructively flushes the deferred queue - it doesn't
447  * call the wireless stack on each mbuf.
448  */
449 static void
450 ath_edma_flush_deferred_queue(struct ath_softc *sc)
451 {
452 	struct ath_buf *bf, *next;
453 
454 	ATH_RX_LOCK_ASSERT(sc);
455 
456 	/* Free in one set, inside the lock */
457 	TAILQ_FOREACH_SAFE(bf,
458 	    &sc->sc_rx_rxlist[HAL_RX_QUEUE_LP], bf_list, next) {
459 		/* Free the buffer/mbuf */
460 		ath_edma_rxbuf_free(sc, bf);
461 	}
462 	TAILQ_FOREACH_SAFE(bf,
463 	    &sc->sc_rx_rxlist[HAL_RX_QUEUE_HP], bf_list, next) {
464 		/* Free the buffer/mbuf */
465 		ath_edma_rxbuf_free(sc, bf);
466 	}
467 }
468 
469 static int
470 ath_edma_recv_proc_deferred_queue(struct ath_softc *sc, HAL_RX_QUEUE qtype,
471     int dosched)
472 {
473 	int ngood = 0;
474 	uint64_t tsf;
475 	struct ath_buf *bf, *next;
476 	struct ath_rx_status *rs;
477 	int16_t nf;
478 	ath_bufhead rxlist;
479 	struct mbuf *m;
480 
481 	TAILQ_INIT(&rxlist);
482 
483 	nf = ath_hal_getchannoise(sc->sc_ah, sc->sc_curchan);
484 	/*
485 	 * XXX TODO: the NF/TSF should be stamped on the bufs themselves,
486 	 * otherwise we may end up adding in the wrong values if this
487 	 * is delayed too far..
488 	 */
489 	tsf = ath_hal_gettsf64(sc->sc_ah);
490 
491 	/* Copy the list over */
492 	ATH_RX_LOCK(sc);
493 	TAILQ_CONCAT(&rxlist, &sc->sc_rx_rxlist[qtype], bf_list);
494 	ATH_RX_UNLOCK(sc);
495 
496 	/* Handle the completed descriptors */
497 	TAILQ_FOREACH_SAFE(bf, &rxlist, bf_list, next) {
498 		/*
499 		 * Skip the RX descriptor status - start at the data offset
500 		 */
501 		m_adj(bf->bf_m, sc->sc_rx_statuslen);
502 
503 		/* Handle the frame */
504 
505 		rs = &bf->bf_status.ds_rxstat;
506 		m = bf->bf_m;
507 		bf->bf_m = NULL;
508 		if (ath_rx_pkt(sc, rs, bf->bf_rxstatus, tsf, nf, qtype, bf, m))
509 			ngood++;
510 	}
511 
512 	if (ngood) {
513 		sc->sc_lastrx = tsf;
514 	}
515 
516 	ATH_KTR(sc, ATH_KTR_INTERRUPTS, 1,
517 	    "ath edma rx deferred proc: ngood=%d\n",
518 	    ngood);
519 
520 	/* Free in one set, inside the lock */
521 	ATH_RX_LOCK(sc);
522 	TAILQ_FOREACH_SAFE(bf, &rxlist, bf_list, next) {
523 		/* Free the buffer/mbuf */
524 		ath_edma_rxbuf_free(sc, bf);
525 	}
526 	ATH_RX_UNLOCK(sc);
527 
528 	return (ngood);
529 }
530 
531 static void
532 ath_edma_recv_tasklet(void *arg, int npending)
533 {
534 	struct ath_softc *sc = (struct ath_softc *) arg;
535 	struct ifnet *ifp = sc->sc_ifp;
536 #ifdef	IEEE80211_SUPPORT_SUPERG
537 	struct ieee80211com *ic = ifp->if_l2com;
538 #endif
539 
540 	DPRINTF(sc, ATH_DEBUG_EDMA_RX, "%s: called; npending=%d\n",
541 	    __func__,
542 	    npending);
543 
544 	ATH_PCU_LOCK(sc);
545 	if (sc->sc_inreset_cnt > 0) {
546 		device_printf(sc->sc_dev, "%s: sc_inreset_cnt > 0; skipping\n",
547 		    __func__);
548 		ATH_PCU_UNLOCK(sc);
549 		return;
550 	}
551 	sc->sc_rxproc_cnt++;
552 	ATH_PCU_UNLOCK(sc);
553 
554 	ath_edma_recv_proc_queue(sc, HAL_RX_QUEUE_HP, 1);
555 	ath_edma_recv_proc_queue(sc, HAL_RX_QUEUE_LP, 1);
556 
557 	ath_edma_recv_proc_deferred_queue(sc, HAL_RX_QUEUE_HP, 1);
558 	ath_edma_recv_proc_deferred_queue(sc, HAL_RX_QUEUE_LP, 1);
559 
560 	/* XXX inside IF_LOCK ? */
561 	if ((ifp->if_drv_flags & IFF_DRV_OACTIVE) == 0) {
562 #ifdef	IEEE80211_SUPPORT_SUPERG
563 		ieee80211_ff_age_all(ic, 100);
564 #endif
565 		if (! IFQ_IS_EMPTY(&ifp->if_snd))
566 			ath_tx_kick(sc);
567 	}
568 	if (ath_dfs_tasklet_needed(sc, sc->sc_curchan))
569 		taskqueue_enqueue(sc->sc_tq, &sc->sc_dfstask);
570 
571 	ATH_PCU_LOCK(sc);
572 	sc->sc_rxproc_cnt--;
573 	ATH_PCU_UNLOCK(sc);
574 }
575 
576 /*
577  * Allocate an RX mbuf for the given ath_buf and initialise
578  * it for EDMA.
579  *
580  * + Allocate a 4KB mbuf;
581  * + Setup the DMA map for the given buffer;
582  * + Return that.
583  */
584 static int
585 ath_edma_rxbuf_init(struct ath_softc *sc, struct ath_buf *bf)
586 {
587 
588 	struct mbuf *m;
589 	int error;
590 	int len;
591 
592 	ATH_RX_LOCK_ASSERT(sc);
593 
594 	m = m_getm(NULL, sc->sc_edma_bufsize, M_NOWAIT, MT_DATA);
595 	if (! m)
596 		return (ENOBUFS);		/* XXX ?*/
597 
598 	/* XXX warn/enforce alignment */
599 
600 	len = m->m_ext.ext_size;
601 #if 0
602 	device_printf(sc->sc_dev, "%s: called: m=%p, size=%d, mtod=%p\n",
603 	    __func__,
604 	    m,
605 	    len,
606 	    mtod(m, char *));
607 #endif
608 
609 	m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;
610 
611 	/*
612 	 * Populate ath_buf fields.
613 	 */
614 	bf->bf_desc = mtod(m, struct ath_desc *);
615 	bf->bf_lastds = bf->bf_desc;	/* XXX only really for TX? */
616 	bf->bf_m = m;
617 
618 	/*
619 	 * Zero the descriptor and ensure it makes it out to the
620 	 * bounce buffer if one is required.
621 	 *
622 	 * XXX PREWRITE will copy the whole buffer; we only needed it
623 	 * to sync the first 32 DWORDS.  Oh well.
624 	 */
625 	memset(bf->bf_desc, '\0', sc->sc_rx_statuslen);
626 
627 	/*
628 	 * Create DMA mapping.
629 	 */
630 	error = bus_dmamap_load_mbuf_sg(sc->sc_dmat,
631 	    bf->bf_dmamap, m, bf->bf_segs, &bf->bf_nseg, BUS_DMA_NOWAIT);
632 
633 	if (error != 0) {
634 		device_printf(sc->sc_dev, "%s: failed; error=%d\n",
635 		    __func__,
636 		    error);
637 		m_freem(m);
638 		return (error);
639 	}
640 
641 	/*
642 	 * Set daddr to the physical mapping page.
643 	 */
644 	bf->bf_daddr = bf->bf_segs[0].ds_addr;
645 
646 	/*
647 	 * Prepare for the upcoming read.
648 	 *
649 	 * We need to both sync some data into the buffer (the zero'ed
650 	 * descriptor payload) and also prepare for the read that's going
651 	 * to occur.
652 	 */
653 	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
654 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
655 
656 	/* Finish! */
657 	return (0);
658 }
659 
660 /*
661  * Allocate a RX buffer.
662  */
663 static struct ath_buf *
664 ath_edma_rxbuf_alloc(struct ath_softc *sc)
665 {
666 	struct ath_buf *bf;
667 	int error;
668 
669 	ATH_RX_LOCK_ASSERT(sc);
670 
671 	/* Allocate buffer */
672 	bf = TAILQ_FIRST(&sc->sc_rxbuf);
673 	/* XXX shouldn't happen upon startup? */
674 	if (bf == NULL) {
675 		device_printf(sc->sc_dev, "%s: nothing on rxbuf?!\n",
676 		    __func__);
677 		return (NULL);
678 	}
679 
680 	/* Remove it from the free list */
681 	TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
682 
683 	/* Assign RX mbuf to it */
684 	error = ath_edma_rxbuf_init(sc, bf);
685 	if (error != 0) {
686 		device_printf(sc->sc_dev,
687 		    "%s: bf=%p, rxbuf alloc failed! error=%d\n",
688 		    __func__,
689 		    bf,
690 		    error);
691 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
692 		return (NULL);
693 	}
694 
695 	return (bf);
696 }
697 
698 static void
699 ath_edma_rxbuf_free(struct ath_softc *sc, struct ath_buf *bf)
700 {
701 
702 	ATH_RX_LOCK_ASSERT(sc);
703 
704 	/*
705 	 * Only unload the frame if we haven't consumed
706 	 * the mbuf via ath_rx_pkt().
707 	 */
708 	if (bf->bf_m) {
709 		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
710 		m_freem(bf->bf_m);
711 		bf->bf_m = NULL;
712 	}
713 
714 	/* XXX lock? */
715 	TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
716 }
717 
718 /*
719  * Allocate up to 'n' entries and push them onto the hardware FIFO.
720  *
721  * Return how many entries were successfully pushed onto the
722  * FIFO.
723  */
724 static int
725 ath_edma_rxfifo_alloc(struct ath_softc *sc, HAL_RX_QUEUE qtype, int nbufs)
726 {
727 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
728 	struct ath_buf *bf;
729 	int i;
730 
731 	ATH_RX_LOCK_ASSERT(sc);
732 
733 	/*
734 	 * Allocate buffers until the FIFO is full or nbufs is reached.
735 	 */
736 	for (i = 0; i < nbufs && re->m_fifo_depth < re->m_fifolen; i++) {
737 		/* Ensure the FIFO is already blank, complain loudly! */
738 		if (re->m_fifo[re->m_fifo_tail] != NULL) {
739 			device_printf(sc->sc_dev,
740 			    "%s: Q%d: fifo[%d] != NULL (%p)\n",
741 			    __func__,
742 			    qtype,
743 			    re->m_fifo_tail,
744 			    re->m_fifo[re->m_fifo_tail]);
745 
746 			/* Free the slot */
747 			ath_edma_rxbuf_free(sc, re->m_fifo[re->m_fifo_tail]);
748 			re->m_fifo_depth--;
749 			/* XXX check it's not < 0 */
750 			re->m_fifo[re->m_fifo_tail] = NULL;
751 		}
752 
753 		bf = ath_edma_rxbuf_alloc(sc);
754 		/* XXX should ensure the FIFO is not NULL? */
755 		if (bf == NULL) {
756 			device_printf(sc->sc_dev,
757 			    "%s: Q%d: alloc failed: i=%d, nbufs=%d?\n",
758 			    __func__,
759 			    qtype,
760 			    i,
761 			    nbufs);
762 			break;
763 		}
764 
765 		re->m_fifo[re->m_fifo_tail] = bf;
766 
767 		/* Write to the RX FIFO */
768 		DPRINTF(sc, ATH_DEBUG_EDMA_RX,
769 		    "%s: Q%d: putrxbuf=%p (0x%jx)\n",
770 		    __func__,
771 		    qtype,
772 		    bf->bf_desc,
773 		    (uintmax_t) bf->bf_daddr);
774 		ath_hal_putrxbuf(sc->sc_ah, bf->bf_daddr, qtype);
775 
776 		re->m_fifo_depth++;
777 		INCR(re->m_fifo_tail, re->m_fifolen);
778 	}
779 
780 	/*
781 	 * Return how many were allocated.
782 	 */
783 	DPRINTF(sc, ATH_DEBUG_EDMA_RX, "%s: Q%d: nbufs=%d, nalloced=%d\n",
784 	    __func__,
785 	    qtype,
786 	    nbufs,
787 	    i);
788 	return (i);
789 }
790 
791 static int
792 ath_edma_rxfifo_flush(struct ath_softc *sc, HAL_RX_QUEUE qtype)
793 {
794 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
795 	int i;
796 
797 	ATH_RX_LOCK_ASSERT(sc);
798 
799 	for (i = 0; i < re->m_fifolen; i++) {
800 		if (re->m_fifo[i] != NULL) {
801 #ifdef	ATH_DEBUG
802 			struct ath_buf *bf = re->m_fifo[i];
803 
804 			if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
805 				ath_printrxbuf(sc, bf, 0, HAL_OK);
806 #endif
807 			ath_edma_rxbuf_free(sc, re->m_fifo[i]);
808 			re->m_fifo[i] = NULL;
809 			re->m_fifo_depth--;
810 		}
811 	}
812 
813 	if (re->m_rxpending != NULL) {
814 		m_freem(re->m_rxpending);
815 		re->m_rxpending = NULL;
816 	}
817 	re->m_fifo_head = re->m_fifo_tail = re->m_fifo_depth = 0;
818 
819 	return (0);
820 }
821 
822 /*
823  * Setup the initial RX FIFO structure.
824  */
825 static int
826 ath_edma_setup_rxfifo(struct ath_softc *sc, HAL_RX_QUEUE qtype)
827 {
828 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
829 
830 	ATH_RX_LOCK_ASSERT(sc);
831 
832 	if (! ath_hal_getrxfifodepth(sc->sc_ah, qtype, &re->m_fifolen)) {
833 		device_printf(sc->sc_dev, "%s: qtype=%d, failed\n",
834 		    __func__,
835 		    qtype);
836 		return (-EINVAL);
837 	}
838 	device_printf(sc->sc_dev, "%s: type=%d, FIFO depth = %d entries\n",
839 	    __func__,
840 	    qtype,
841 	    re->m_fifolen);
842 
843 	/* Allocate ath_buf FIFO array, pre-zero'ed */
844 	re->m_fifo = malloc(sizeof(struct ath_buf *) * re->m_fifolen,
845 	    M_ATHDEV,
846 	    M_NOWAIT | M_ZERO);
847 	if (re->m_fifo == NULL) {
848 		device_printf(sc->sc_dev, "%s: malloc failed\n",
849 		    __func__);
850 		return (-ENOMEM);
851 	}
852 
853 	/*
854 	 * Set initial "empty" state.
855 	 */
856 	re->m_rxpending = NULL;
857 	re->m_fifo_head = re->m_fifo_tail = re->m_fifo_depth = 0;
858 
859 	return (0);
860 }
861 
862 static int
863 ath_edma_rxfifo_free(struct ath_softc *sc, HAL_RX_QUEUE qtype)
864 {
865 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
866 
867 	device_printf(sc->sc_dev, "%s: called; qtype=%d\n",
868 	    __func__,
869 	    qtype);
870 
871 	free(re->m_fifo, M_ATHDEV);
872 
873 	return (0);
874 }
875 
876 static int
877 ath_edma_dma_rxsetup(struct ath_softc *sc)
878 {
879 	int error;
880 
881 	/*
882 	 * Create RX DMA tag and buffers.
883 	 */
884 	error = ath_descdma_setup_rx_edma(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
885 	    "rx", ath_rxbuf, sc->sc_rx_statuslen);
886 	if (error != 0)
887 		return error;
888 
889 	ATH_RX_LOCK(sc);
890 	(void) ath_edma_setup_rxfifo(sc, HAL_RX_QUEUE_HP);
891 	(void) ath_edma_setup_rxfifo(sc, HAL_RX_QUEUE_LP);
892 	ATH_RX_UNLOCK(sc);
893 
894 	return (0);
895 }
896 
897 static int
898 ath_edma_dma_rxteardown(struct ath_softc *sc)
899 {
900 
901 	ATH_RX_LOCK(sc);
902 	ath_edma_flush_deferred_queue(sc);
903 	ath_edma_rxfifo_flush(sc, HAL_RX_QUEUE_HP);
904 	ath_edma_rxfifo_free(sc, HAL_RX_QUEUE_HP);
905 
906 	ath_edma_rxfifo_flush(sc, HAL_RX_QUEUE_LP);
907 	ath_edma_rxfifo_free(sc, HAL_RX_QUEUE_LP);
908 	ATH_RX_UNLOCK(sc);
909 
910 	/* Free RX ath_buf */
911 	/* Free RX DMA tag */
912 	if (sc->sc_rxdma.dd_desc_len != 0)
913 		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
914 
915 	return (0);
916 }
917 
918 void
919 ath_recv_setup_edma(struct ath_softc *sc)
920 {
921 
922 	/* Set buffer size to 4k */
923 	sc->sc_edma_bufsize = 4096;
924 
925 	/* Fetch EDMA field and buffer sizes */
926 	(void) ath_hal_getrxstatuslen(sc->sc_ah, &sc->sc_rx_statuslen);
927 
928 	/* Configure the hardware with the RX buffer size */
929 	(void) ath_hal_setrxbufsize(sc->sc_ah, sc->sc_edma_bufsize -
930 	    sc->sc_rx_statuslen);
931 
932 	device_printf(sc->sc_dev, "RX status length: %d\n",
933 	    sc->sc_rx_statuslen);
934 	device_printf(sc->sc_dev, "RX buffer size: %d\n",
935 	    sc->sc_edma_bufsize);
936 
937 	sc->sc_rx.recv_stop = ath_edma_stoprecv;
938 	sc->sc_rx.recv_start = ath_edma_startrecv;
939 	sc->sc_rx.recv_flush = ath_edma_recv_flush;
940 	sc->sc_rx.recv_tasklet = ath_edma_recv_tasklet;
941 	sc->sc_rx.recv_rxbuf_init = ath_edma_rxbuf_init;
942 
943 	sc->sc_rx.recv_setup = ath_edma_dma_rxsetup;
944 	sc->sc_rx.recv_teardown = ath_edma_dma_rxteardown;
945 
946 	sc->sc_rx.recv_sched = ath_edma_recv_sched;
947 	sc->sc_rx.recv_sched_queue = ath_edma_recv_sched_queue;
948 }
949