xref: /freebsd/sys/dev/ath/if_ath_rx.c (revision 1f4bcc459a76b7aa664f3fd557684cd0ba6da352)
1 /*-
2  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
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_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 #ifdef	ATH_DEBUG_ALQ
121 #include <dev/ath/if_ath_alq.h>
122 #endif
123 
124 #include <dev/ath/if_ath_lna_div.h>
125 
126 /*
127  * Calculate the receive filter according to the
128  * operating mode and state:
129  *
130  * o always accept unicast, broadcast, and multicast traffic
131  * o accept PHY error frames when hardware doesn't have MIB support
132  *   to count and we need them for ANI (sta mode only until recently)
133  *   and we are not scanning (ANI is disabled)
134  *   NB: older hal's add rx filter bits out of sight and we need to
135  *	 blindly preserve them
136  * o probe request frames are accepted only when operating in
137  *   hostap, adhoc, mesh, or monitor modes
138  * o enable promiscuous mode
139  *   - when in monitor mode
140  *   - if interface marked PROMISC (assumes bridge setting is filtered)
141  * o accept beacons:
142  *   - when operating in station mode for collecting rssi data when
143  *     the station is otherwise quiet, or
144  *   - when operating in adhoc mode so the 802.11 layer creates
145  *     node table entries for peers,
146  *   - when scanning
147  *   - when doing s/w beacon miss (e.g. for ap+sta)
148  *   - when operating in ap mode in 11g to detect overlapping bss that
149  *     require protection
150  *   - when operating in mesh mode to detect neighbors
151  * o accept control frames:
152  *   - when in monitor mode
153  * XXX HT protection for 11n
154  */
155 u_int32_t
156 ath_calcrxfilter(struct ath_softc *sc)
157 {
158 	struct ieee80211com *ic = &sc->sc_ic;
159 	u_int32_t rfilt;
160 
161 	rfilt = HAL_RX_FILTER_UCAST | HAL_RX_FILTER_BCAST | HAL_RX_FILTER_MCAST;
162 	if (!sc->sc_needmib && !sc->sc_scanning)
163 		rfilt |= HAL_RX_FILTER_PHYERR;
164 	if (ic->ic_opmode != IEEE80211_M_STA)
165 		rfilt |= HAL_RX_FILTER_PROBEREQ;
166 	/* XXX ic->ic_monvaps != 0? */
167 	if (ic->ic_opmode == IEEE80211_M_MONITOR || ic->ic_promisc > 0)
168 		rfilt |= HAL_RX_FILTER_PROM;
169 
170 	/*
171 	 * Only listen to all beacons if we're scanning.
172 	 *
173 	 * Otherwise we only really need to hear beacons from
174 	 * our own BSSID.
175 	 *
176 	 * IBSS? software beacon miss? Just receive all beacons.
177 	 * We need to hear beacons/probe requests from everyone so
178 	 * we can merge ibss.
179 	 */
180 	if (ic->ic_opmode == IEEE80211_M_IBSS || sc->sc_swbmiss) {
181 		rfilt |= HAL_RX_FILTER_BEACON;
182 	} else if (ic->ic_opmode == IEEE80211_M_STA) {
183 		if (sc->sc_do_mybeacon && ! sc->sc_scanning) {
184 			rfilt |= HAL_RX_FILTER_MYBEACON;
185 		} else { /* scanning, non-mybeacon chips */
186 			rfilt |= HAL_RX_FILTER_BEACON;
187 		}
188 	}
189 
190 	/*
191 	 * NB: We don't recalculate the rx filter when
192 	 * ic_protmode changes; otherwise we could do
193 	 * this only when ic_protmode != NONE.
194 	 */
195 	if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
196 	    IEEE80211_IS_CHAN_ANYG(ic->ic_curchan))
197 		rfilt |= HAL_RX_FILTER_BEACON;
198 
199 	/*
200 	 * Enable hardware PS-POLL RX only for hostap mode;
201 	 * STA mode sends PS-POLL frames but never
202 	 * receives them.
203 	 */
204 	if (ath_hal_getcapability(sc->sc_ah, HAL_CAP_PSPOLL,
205 	    0, NULL) == HAL_OK &&
206 	    ic->ic_opmode == IEEE80211_M_HOSTAP)
207 		rfilt |= HAL_RX_FILTER_PSPOLL;
208 
209 	if (sc->sc_nmeshvaps) {
210 		rfilt |= HAL_RX_FILTER_BEACON;
211 		if (sc->sc_hasbmatch)
212 			rfilt |= HAL_RX_FILTER_BSSID;
213 		else
214 			rfilt |= HAL_RX_FILTER_PROM;
215 	}
216 	if (ic->ic_opmode == IEEE80211_M_MONITOR)
217 		rfilt |= HAL_RX_FILTER_CONTROL;
218 
219 	/*
220 	 * Enable RX of compressed BAR frames only when doing
221 	 * 802.11n. Required for A-MPDU.
222 	 */
223 	if (IEEE80211_IS_CHAN_HT(ic->ic_curchan))
224 		rfilt |= HAL_RX_FILTER_COMPBAR;
225 
226 	/*
227 	 * Enable radar PHY errors if requested by the
228 	 * DFS module.
229 	 */
230 	if (sc->sc_dodfs)
231 		rfilt |= HAL_RX_FILTER_PHYRADAR;
232 
233 	/*
234 	 * Enable spectral PHY errors if requested by the
235 	 * spectral module.
236 	 */
237 	if (sc->sc_dospectral)
238 		rfilt |= HAL_RX_FILTER_PHYRADAR;
239 
240 	DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x, %s\n",
241 	    __func__, rfilt, ieee80211_opmode_name[ic->ic_opmode]);
242 	return rfilt;
243 }
244 
245 static int
246 ath_legacy_rxbuf_init(struct ath_softc *sc, struct ath_buf *bf)
247 {
248 	struct ath_hal *ah = sc->sc_ah;
249 	int error;
250 	struct mbuf *m;
251 	struct ath_desc *ds;
252 
253 	/* XXX TODO: ATH_RX_LOCK_ASSERT(sc); */
254 
255 	m = bf->bf_m;
256 	if (m == NULL) {
257 		/*
258 		 * NB: by assigning a page to the rx dma buffer we
259 		 * implicitly satisfy the Atheros requirement that
260 		 * this buffer be cache-line-aligned and sized to be
261 		 * multiple of the cache line size.  Not doing this
262 		 * causes weird stuff to happen (for the 5210 at least).
263 		 */
264 		m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
265 		if (m == NULL) {
266 			DPRINTF(sc, ATH_DEBUG_ANY,
267 				"%s: no mbuf/cluster\n", __func__);
268 			sc->sc_stats.ast_rx_nombuf++;
269 			return ENOMEM;
270 		}
271 		m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;
272 
273 		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat,
274 					     bf->bf_dmamap, m,
275 					     bf->bf_segs, &bf->bf_nseg,
276 					     BUS_DMA_NOWAIT);
277 		if (error != 0) {
278 			DPRINTF(sc, ATH_DEBUG_ANY,
279 			    "%s: bus_dmamap_load_mbuf_sg failed; error %d\n",
280 			    __func__, error);
281 			sc->sc_stats.ast_rx_busdma++;
282 			m_freem(m);
283 			return error;
284 		}
285 		KASSERT(bf->bf_nseg == 1,
286 			("multi-segment packet; nseg %u", bf->bf_nseg));
287 		bf->bf_m = m;
288 	}
289 	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREREAD);
290 
291 	/*
292 	 * Setup descriptors.  For receive we always terminate
293 	 * the descriptor list with a self-linked entry so we'll
294 	 * not get overrun under high load (as can happen with a
295 	 * 5212 when ANI processing enables PHY error frames).
296 	 *
297 	 * To insure the last descriptor is self-linked we create
298 	 * each descriptor as self-linked and add it to the end.  As
299 	 * each additional descriptor is added the previous self-linked
300 	 * entry is ``fixed'' naturally.  This should be safe even
301 	 * if DMA is happening.  When processing RX interrupts we
302 	 * never remove/process the last, self-linked, entry on the
303 	 * descriptor list.  This insures the hardware always has
304 	 * someplace to write a new frame.
305 	 */
306 	/*
307 	 * 11N: we can no longer afford to self link the last descriptor.
308 	 * MAC acknowledges BA status as long as it copies frames to host
309 	 * buffer (or rx fifo). This can incorrectly acknowledge packets
310 	 * to a sender if last desc is self-linked.
311 	 */
312 	ds = bf->bf_desc;
313 	if (sc->sc_rxslink)
314 		ds->ds_link = bf->bf_daddr;	/* link to self */
315 	else
316 		ds->ds_link = 0;		/* terminate the list */
317 	ds->ds_data = bf->bf_segs[0].ds_addr;
318 	ath_hal_setuprxdesc(ah, ds
319 		, m->m_len		/* buffer size */
320 		, 0
321 	);
322 
323 	if (sc->sc_rxlink != NULL)
324 		*sc->sc_rxlink = bf->bf_daddr;
325 	sc->sc_rxlink = &ds->ds_link;
326 	return 0;
327 }
328 
329 /*
330  * Intercept management frames to collect beacon rssi data
331  * and to do ibss merges.
332  */
333 void
334 ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
335 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
336 {
337 	struct ieee80211vap *vap = ni->ni_vap;
338 	struct ath_softc *sc = vap->iv_ic->ic_softc;
339 	uint64_t tsf_beacon_old, tsf_beacon;
340 	uint64_t nexttbtt;
341 	int64_t tsf_delta;
342 	int32_t tsf_delta_bmiss;
343 	int32_t tsf_remainder;
344 	uint64_t tsf_beacon_target;
345 	int tsf_intval;
346 
347 	tsf_beacon_old = ((uint64_t) LE_READ_4(ni->ni_tstamp.data + 4)) << 32;
348 	tsf_beacon_old |= LE_READ_4(ni->ni_tstamp.data);
349 
350 #define	TU_TO_TSF(_tu)	(((u_int64_t)(_tu)) << 10)
351 	tsf_intval = 1;
352 	if (ni->ni_intval > 0) {
353 		tsf_intval = TU_TO_TSF(ni->ni_intval);
354 	}
355 #undef	TU_TO_TSF
356 
357 	/*
358 	 * Call up first so subsequent work can use information
359 	 * potentially stored in the node (e.g. for ibss merge).
360 	 */
361 	ATH_VAP(vap)->av_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
362 	switch (subtype) {
363 	case IEEE80211_FC0_SUBTYPE_BEACON:
364 		/* update rssi statistics for use by the hal */
365 		/* XXX unlocked check against vap->iv_bss? */
366 		ATH_RSSI_LPF(sc->sc_halstats.ns_avgbrssi, rssi);
367 
368 		tsf_beacon = ((uint64_t) LE_READ_4(ni->ni_tstamp.data + 4)) << 32;
369 		tsf_beacon |= LE_READ_4(ni->ni_tstamp.data);
370 
371 		nexttbtt = ath_hal_getnexttbtt(sc->sc_ah);
372 
373 		/*
374 		 * Let's calculate the delta and remainder, so we can see
375 		 * if the beacon timer from the AP is varying by more than
376 		 * a few TU.  (Which would be a huge, huge problem.)
377 		 */
378 		tsf_delta = (long long) tsf_beacon - (long long) tsf_beacon_old;
379 
380 		tsf_delta_bmiss = tsf_delta / tsf_intval;
381 
382 		/*
383 		 * If our delta is greater than half the beacon interval,
384 		 * let's round the bmiss value up to the next beacon
385 		 * interval.  Ie, we're running really, really early
386 		 * on the next beacon.
387 		 */
388 		if (tsf_delta % tsf_intval > (tsf_intval / 2))
389 			tsf_delta_bmiss ++;
390 
391 		tsf_beacon_target = tsf_beacon_old +
392 		    (((unsigned long long) tsf_delta_bmiss) * (long long) tsf_intval);
393 
394 		/*
395 		 * The remainder using '%' is between 0 .. intval-1.
396 		 * If we're actually running too fast, then the remainder
397 		 * will be some large number just under intval-1.
398 		 * So we need to look at whether we're running
399 		 * before or after the target beacon interval
400 		 * and if we are, modify how we do the remainder
401 		 * calculation.
402 		 */
403 		if (tsf_beacon < tsf_beacon_target) {
404 			tsf_remainder =
405 			    -(tsf_intval - ((tsf_beacon - tsf_beacon_old) % tsf_intval));
406 		} else {
407 			tsf_remainder = (tsf_beacon - tsf_beacon_old) % tsf_intval;
408 		}
409 
410 		DPRINTF(sc, ATH_DEBUG_BEACON, "%s: old_tsf=%llu, new_tsf=%llu, target_tsf=%llu, delta=%lld, bmiss=%d, remainder=%d\n",
411 		    __func__,
412 		    (unsigned long long) tsf_beacon_old,
413 		    (unsigned long long) tsf_beacon,
414 		    (unsigned long long) tsf_beacon_target,
415 		    (long long) tsf_delta,
416 		    tsf_delta_bmiss,
417 		    tsf_remainder);
418 
419 		DPRINTF(sc, ATH_DEBUG_BEACON, "%s: tsf=%llu, nexttbtt=%llu, delta=%d\n",
420 		    __func__,
421 		    (unsigned long long) tsf_beacon,
422 		    (unsigned long long) nexttbtt,
423 		    (int32_t) tsf_beacon - (int32_t) nexttbtt + tsf_intval);
424 
425 		if (sc->sc_syncbeacon &&
426 		    ni == vap->iv_bss &&
427 		    (vap->iv_state == IEEE80211_S_RUN || vap->iv_state == IEEE80211_S_SLEEP)) {
428 			DPRINTF(sc, ATH_DEBUG_BEACON,
429 			    "%s: syncbeacon=1; syncing\n",
430 			    __func__);
431 			/*
432 			 * Resync beacon timers using the tsf of the beacon
433 			 * frame we just received.
434 			 */
435 			ath_beacon_config(sc, vap);
436 			sc->sc_syncbeacon = 0;
437 		}
438 
439 		/* fall thru... */
440 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
441 		if (vap->iv_opmode == IEEE80211_M_IBSS &&
442 		    vap->iv_state == IEEE80211_S_RUN) {
443 			uint32_t rstamp = sc->sc_lastrs->rs_tstamp;
444 			uint64_t tsf = ath_extend_tsf(sc, rstamp,
445 				ath_hal_gettsf64(sc->sc_ah));
446 			/*
447 			 * Handle ibss merge as needed; check the tsf on the
448 			 * frame before attempting the merge.  The 802.11 spec
449 			 * says the station should change it's bssid to match
450 			 * the oldest station with the same ssid, where oldest
451 			 * is determined by the tsf.  Note that hardware
452 			 * reconfiguration happens through callback to
453 			 * ath_newstate as the state machine will go from
454 			 * RUN -> RUN when this happens.
455 			 */
456 			if (le64toh(ni->ni_tstamp.tsf) >= tsf) {
457 				DPRINTF(sc, ATH_DEBUG_STATE,
458 				    "ibss merge, rstamp %u tsf %ju "
459 				    "tstamp %ju\n", rstamp, (uintmax_t)tsf,
460 				    (uintmax_t)ni->ni_tstamp.tsf);
461 				(void) ieee80211_ibss_merge(ni);
462 			}
463 		}
464 		break;
465 	}
466 }
467 
468 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
469 static void
470 ath_rx_tap_vendor(struct ath_softc *sc, struct mbuf *m,
471     const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
472 {
473 
474 	/* Fill in the extension bitmap */
475 	sc->sc_rx_th.wr_ext_bitmap = htole32(1 << ATH_RADIOTAP_VENDOR_HEADER);
476 
477 	/* Fill in the vendor header */
478 	sc->sc_rx_th.wr_vh.vh_oui[0] = 0x7f;
479 	sc->sc_rx_th.wr_vh.vh_oui[1] = 0x03;
480 	sc->sc_rx_th.wr_vh.vh_oui[2] = 0x00;
481 
482 	/* XXX what should this be? */
483 	sc->sc_rx_th.wr_vh.vh_sub_ns = 0;
484 	sc->sc_rx_th.wr_vh.vh_skip_len =
485 	    htole16(sizeof(struct ath_radiotap_vendor_hdr));
486 
487 	/* General version info */
488 	sc->sc_rx_th.wr_v.vh_version = 1;
489 
490 	sc->sc_rx_th.wr_v.vh_rx_chainmask = sc->sc_rxchainmask;
491 
492 	/* rssi */
493 	sc->sc_rx_th.wr_v.rssi_ctl[0] = rs->rs_rssi_ctl[0];
494 	sc->sc_rx_th.wr_v.rssi_ctl[1] = rs->rs_rssi_ctl[1];
495 	sc->sc_rx_th.wr_v.rssi_ctl[2] = rs->rs_rssi_ctl[2];
496 	sc->sc_rx_th.wr_v.rssi_ext[0] = rs->rs_rssi_ext[0];
497 	sc->sc_rx_th.wr_v.rssi_ext[1] = rs->rs_rssi_ext[1];
498 	sc->sc_rx_th.wr_v.rssi_ext[2] = rs->rs_rssi_ext[2];
499 
500 	/* evm */
501 	sc->sc_rx_th.wr_v.evm[0] = rs->rs_evm0;
502 	sc->sc_rx_th.wr_v.evm[1] = rs->rs_evm1;
503 	sc->sc_rx_th.wr_v.evm[2] = rs->rs_evm2;
504 	/* These are only populated from the AR9300 or later */
505 	sc->sc_rx_th.wr_v.evm[3] = rs->rs_evm3;
506 	sc->sc_rx_th.wr_v.evm[4] = rs->rs_evm4;
507 
508 	/* direction */
509 	sc->sc_rx_th.wr_v.vh_flags = ATH_VENDOR_PKT_RX;
510 
511 	/* RX rate */
512 	sc->sc_rx_th.wr_v.vh_rx_hwrate = rs->rs_rate;
513 
514 	/* RX flags */
515 	sc->sc_rx_th.wr_v.vh_rs_flags = rs->rs_flags;
516 
517 	if (rs->rs_isaggr)
518 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_ISAGGR;
519 	if (rs->rs_moreaggr)
520 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_MOREAGGR;
521 
522 	/* phyerr info */
523 	if (rs->rs_status & HAL_RXERR_PHY) {
524 		sc->sc_rx_th.wr_v.vh_phyerr_code = rs->rs_phyerr;
525 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_RXPHYERR;
526 	} else {
527 		sc->sc_rx_th.wr_v.vh_phyerr_code = 0xff;
528 	}
529 	sc->sc_rx_th.wr_v.vh_rs_status = rs->rs_status;
530 	sc->sc_rx_th.wr_v.vh_rssi = rs->rs_rssi;
531 }
532 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
533 
534 static void
535 ath_rx_tap(struct ath_softc *sc, struct mbuf *m,
536 	const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
537 {
538 #define	CHAN_HT20	htole32(IEEE80211_CHAN_HT20)
539 #define	CHAN_HT40U	htole32(IEEE80211_CHAN_HT40U)
540 #define	CHAN_HT40D	htole32(IEEE80211_CHAN_HT40D)
541 #define	CHAN_HT		(CHAN_HT20|CHAN_HT40U|CHAN_HT40D)
542 	const HAL_RATE_TABLE *rt;
543 	uint8_t rix;
544 
545 	rt = sc->sc_currates;
546 	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
547 	rix = rt->rateCodeToIndex[rs->rs_rate];
548 	sc->sc_rx_th.wr_rate = sc->sc_hwmap[rix].ieeerate;
549 	sc->sc_rx_th.wr_flags = sc->sc_hwmap[rix].rxflags;
550 #ifdef AH_SUPPORT_AR5416
551 	sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT;
552 	if (rs->rs_status & HAL_RXERR_PHY) {
553 		/*
554 		 * PHY error - make sure the channel flags
555 		 * reflect the actual channel configuration,
556 		 * not the received frame.
557 		 */
558 		if (IEEE80211_IS_CHAN_HT40U(sc->sc_curchan))
559 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
560 		else if (IEEE80211_IS_CHAN_HT40D(sc->sc_curchan))
561 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
562 		else if (IEEE80211_IS_CHAN_HT20(sc->sc_curchan))
563 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
564 	} else if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) {	/* HT rate */
565 		struct ieee80211com *ic = &sc->sc_ic;
566 
567 		if ((rs->rs_flags & HAL_RX_2040) == 0)
568 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
569 		else if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan))
570 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
571 		else
572 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
573 		if ((rs->rs_flags & HAL_RX_GI) == 0)
574 			sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_SHORTGI;
575 	}
576 
577 #endif
578 	sc->sc_rx_th.wr_tsf = htole64(ath_extend_tsf(sc, rs->rs_tstamp, tsf));
579 	if (rs->rs_status & HAL_RXERR_CRC)
580 		sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_BADFCS;
581 	/* XXX propagate other error flags from descriptor */
582 	sc->sc_rx_th.wr_antnoise = nf;
583 	sc->sc_rx_th.wr_antsignal = nf + rs->rs_rssi;
584 	sc->sc_rx_th.wr_antenna = rs->rs_antenna;
585 #undef CHAN_HT
586 #undef CHAN_HT20
587 #undef CHAN_HT40U
588 #undef CHAN_HT40D
589 }
590 
591 static void
592 ath_handle_micerror(struct ieee80211com *ic,
593 	struct ieee80211_frame *wh, int keyix)
594 {
595 	struct ieee80211_node *ni;
596 
597 	/* XXX recheck MIC to deal w/ chips that lie */
598 	/* XXX discard MIC errors on !data frames */
599 	ni = ieee80211_find_rxnode(ic, (const struct ieee80211_frame_min *) wh);
600 	if (ni != NULL) {
601 		ieee80211_notify_michael_failure(ni->ni_vap, wh, keyix);
602 		ieee80211_free_node(ni);
603 	}
604 }
605 
606 /*
607  * Process a single packet.
608  *
609  * The mbuf must already be synced, unmapped and removed from bf->bf_m
610  * by this stage.
611  *
612  * The mbuf must be consumed by this routine - either passed up the
613  * net80211 stack, put on the holding queue, or freed.
614  */
615 int
616 ath_rx_pkt(struct ath_softc *sc, struct ath_rx_status *rs, HAL_STATUS status,
617     uint64_t tsf, int nf, HAL_RX_QUEUE qtype, struct ath_buf *bf,
618     struct mbuf *m)
619 {
620 	uint64_t rstamp;
621 	int len, type;
622 	struct ieee80211com *ic = &sc->sc_ic;
623 	struct ieee80211_node *ni;
624 	int is_good = 0;
625 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
626 
627 	/*
628 	 * Calculate the correct 64 bit TSF given
629 	 * the TSF64 register value and rs_tstamp.
630 	 */
631 	rstamp = ath_extend_tsf(sc, rs->rs_tstamp, tsf);
632 
633 	/* These aren't specifically errors */
634 #ifdef	AH_SUPPORT_AR5416
635 	if (rs->rs_flags & HAL_RX_GI)
636 		sc->sc_stats.ast_rx_halfgi++;
637 	if (rs->rs_flags & HAL_RX_2040)
638 		sc->sc_stats.ast_rx_2040++;
639 	if (rs->rs_flags & HAL_RX_DELIM_CRC_PRE)
640 		sc->sc_stats.ast_rx_pre_crc_err++;
641 	if (rs->rs_flags & HAL_RX_DELIM_CRC_POST)
642 		sc->sc_stats.ast_rx_post_crc_err++;
643 	if (rs->rs_flags & HAL_RX_DECRYPT_BUSY)
644 		sc->sc_stats.ast_rx_decrypt_busy_err++;
645 	if (rs->rs_flags & HAL_RX_HI_RX_CHAIN)
646 		sc->sc_stats.ast_rx_hi_rx_chain++;
647 	if (rs->rs_flags & HAL_RX_STBC)
648 		sc->sc_stats.ast_rx_stbc++;
649 #endif /* AH_SUPPORT_AR5416 */
650 
651 	if (rs->rs_status != 0) {
652 		if (rs->rs_status & HAL_RXERR_CRC)
653 			sc->sc_stats.ast_rx_crcerr++;
654 		if (rs->rs_status & HAL_RXERR_FIFO)
655 			sc->sc_stats.ast_rx_fifoerr++;
656 		if (rs->rs_status & HAL_RXERR_PHY) {
657 			sc->sc_stats.ast_rx_phyerr++;
658 			/* Process DFS radar events */
659 			if ((rs->rs_phyerr == HAL_PHYERR_RADAR) ||
660 			    (rs->rs_phyerr == HAL_PHYERR_FALSE_RADAR_EXT)) {
661 				/* Now pass it to the radar processing code */
662 				ath_dfs_process_phy_err(sc, m, rstamp, rs);
663 			}
664 
665 			/* Be suitably paranoid about receiving phy errors out of the stats array bounds */
666 			if (rs->rs_phyerr < 64)
667 				sc->sc_stats.ast_rx_phy[rs->rs_phyerr]++;
668 			goto rx_error;	/* NB: don't count in ierrors */
669 		}
670 		if (rs->rs_status & HAL_RXERR_DECRYPT) {
671 			/*
672 			 * Decrypt error.  If the error occurred
673 			 * because there was no hardware key, then
674 			 * let the frame through so the upper layers
675 			 * can process it.  This is necessary for 5210
676 			 * parts which have no way to setup a ``clear''
677 			 * key cache entry.
678 			 *
679 			 * XXX do key cache faulting
680 			 */
681 			if (rs->rs_keyix == HAL_RXKEYIX_INVALID)
682 				goto rx_accept;
683 			sc->sc_stats.ast_rx_badcrypt++;
684 		}
685 		/*
686 		 * Similar as above - if the failure was a keymiss
687 		 * just punt it up to the upper layers for now.
688 		 */
689 		if (rs->rs_status & HAL_RXERR_KEYMISS) {
690 			sc->sc_stats.ast_rx_keymiss++;
691 			goto rx_accept;
692 		}
693 		if (rs->rs_status & HAL_RXERR_MIC) {
694 			sc->sc_stats.ast_rx_badmic++;
695 			/*
696 			 * Do minimal work required to hand off
697 			 * the 802.11 header for notification.
698 			 */
699 			/* XXX frag's and qos frames */
700 			len = rs->rs_datalen;
701 			if (len >= sizeof (struct ieee80211_frame)) {
702 				ath_handle_micerror(ic,
703 				    mtod(m, struct ieee80211_frame *),
704 				    sc->sc_splitmic ?
705 					rs->rs_keyix-32 : rs->rs_keyix);
706 			}
707 		}
708 		counter_u64_add(ic->ic_ierrors, 1);
709 rx_error:
710 		/*
711 		 * Cleanup any pending partial frame.
712 		 */
713 		if (re->m_rxpending != NULL) {
714 			m_freem(re->m_rxpending);
715 			re->m_rxpending = NULL;
716 		}
717 		/*
718 		 * When a tap is present pass error frames
719 		 * that have been requested.  By default we
720 		 * pass decrypt+mic errors but others may be
721 		 * interesting (e.g. crc).
722 		 */
723 		if (ieee80211_radiotap_active(ic) &&
724 		    (rs->rs_status & sc->sc_monpass)) {
725 			/* NB: bpf needs the mbuf length setup */
726 			len = rs->rs_datalen;
727 			m->m_pkthdr.len = m->m_len = len;
728 			ath_rx_tap(sc, m, rs, rstamp, nf);
729 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
730 			ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
731 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
732 			ieee80211_radiotap_rx_all(ic, m);
733 		}
734 		/* XXX pass MIC errors up for s/w reclaculation */
735 		m_freem(m); m = NULL;
736 		goto rx_next;
737 	}
738 rx_accept:
739 	len = rs->rs_datalen;
740 	m->m_len = len;
741 
742 	if (rs->rs_more) {
743 		/*
744 		 * Frame spans multiple descriptors; save
745 		 * it for the next completed descriptor, it
746 		 * will be used to construct a jumbogram.
747 		 */
748 		if (re->m_rxpending != NULL) {
749 			/* NB: max frame size is currently 2 clusters */
750 			sc->sc_stats.ast_rx_toobig++;
751 			m_freem(re->m_rxpending);
752 		}
753 		m->m_pkthdr.len = len;
754 		re->m_rxpending = m;
755 		m = NULL;
756 		goto rx_next;
757 	} else if (re->m_rxpending != NULL) {
758 		/*
759 		 * This is the second part of a jumbogram,
760 		 * chain it to the first mbuf, adjust the
761 		 * frame length, and clear the rxpending state.
762 		 */
763 		re->m_rxpending->m_next = m;
764 		re->m_rxpending->m_pkthdr.len += len;
765 		m = re->m_rxpending;
766 		re->m_rxpending = NULL;
767 	} else {
768 		/*
769 		 * Normal single-descriptor receive; setup packet length.
770 		 */
771 		m->m_pkthdr.len = len;
772 	}
773 
774 	/*
775 	 * Validate rs->rs_antenna.
776 	 *
777 	 * Some users w/ AR9285 NICs have reported crashes
778 	 * here because rs_antenna field is bogusly large.
779 	 * Let's enforce the maximum antenna limit of 8
780 	 * (and it shouldn't be hard coded, but that's a
781 	 * separate problem) and if there's an issue, print
782 	 * out an error and adjust rs_antenna to something
783 	 * sensible.
784 	 *
785 	 * This code should be removed once the actual
786 	 * root cause of the issue has been identified.
787 	 * For example, it may be that the rs_antenna
788 	 * field is only valid for the lsat frame of
789 	 * an aggregate and it just happens that it is
790 	 * "mostly" right. (This is a general statement -
791 	 * the majority of the statistics are only valid
792 	 * for the last frame in an aggregate.
793 	 */
794 	if (rs->rs_antenna > 7) {
795 		device_printf(sc->sc_dev, "%s: rs_antenna > 7 (%d)\n",
796 		    __func__, rs->rs_antenna);
797 #ifdef	ATH_DEBUG
798 		ath_printrxbuf(sc, bf, 0, status == HAL_OK);
799 #endif /* ATH_DEBUG */
800 		rs->rs_antenna = 0;	/* XXX better than nothing */
801 	}
802 
803 	/*
804 	 * If this is an AR9285/AR9485, then the receive and LNA
805 	 * configuration is stored in RSSI[2] / EXTRSSI[2].
806 	 * We can extract this out to build a much better
807 	 * receive antenna profile.
808 	 *
809 	 * Yes, this just blurts over the above RX antenna field
810 	 * for now.  It's fine, the AR9285 doesn't really use
811 	 * that.
812 	 *
813 	 * Later on we should store away the fine grained LNA
814 	 * information and keep separate counters just for
815 	 * that.  It'll help when debugging the AR9285/AR9485
816 	 * combined diversity code.
817 	 */
818 	if (sc->sc_rx_lnamixer) {
819 		rs->rs_antenna = 0;
820 
821 		/* Bits 0:1 - the LNA configuration used */
822 		rs->rs_antenna |=
823 		    ((rs->rs_rssi_ctl[2] & HAL_RX_LNA_CFG_USED)
824 		      >> HAL_RX_LNA_CFG_USED_S);
825 
826 		/* Bit 2 - the external RX antenna switch */
827 		if (rs->rs_rssi_ctl[2] & HAL_RX_LNA_EXTCFG)
828 			rs->rs_antenna |= 0x4;
829 	}
830 
831 	sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;
832 
833 	/*
834 	 * Populate the rx status block.  When there are bpf
835 	 * listeners we do the additional work to provide
836 	 * complete status.  Otherwise we fill in only the
837 	 * material required by ieee80211_input.  Note that
838 	 * noise setting is filled in above.
839 	 */
840 	if (ieee80211_radiotap_active(ic)) {
841 		ath_rx_tap(sc, m, rs, rstamp, nf);
842 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
843 		ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
844 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
845 	}
846 
847 	/*
848 	 * From this point on we assume the frame is at least
849 	 * as large as ieee80211_frame_min; verify that.
850 	 */
851 	if (len < IEEE80211_MIN_LEN) {
852 		if (!ieee80211_radiotap_active(ic)) {
853 			DPRINTF(sc, ATH_DEBUG_RECV,
854 			    "%s: short packet %d\n", __func__, len);
855 			sc->sc_stats.ast_rx_tooshort++;
856 		} else {
857 			/* NB: in particular this captures ack's */
858 			ieee80211_radiotap_rx_all(ic, m);
859 		}
860 		m_freem(m); m = NULL;
861 		goto rx_next;
862 	}
863 
864 	if (IFF_DUMPPKTS(sc, ATH_DEBUG_RECV)) {
865 		const HAL_RATE_TABLE *rt = sc->sc_currates;
866 		uint8_t rix = rt->rateCodeToIndex[rs->rs_rate];
867 
868 		ieee80211_dump_pkt(ic, mtod(m, caddr_t), len,
869 		    sc->sc_hwmap[rix].ieeerate, rs->rs_rssi);
870 	}
871 
872 	m_adj(m, -IEEE80211_CRC_LEN);
873 
874 	/*
875 	 * Locate the node for sender, track state, and then
876 	 * pass the (referenced) node up to the 802.11 layer
877 	 * for its use.
878 	 */
879 	ni = ieee80211_find_rxnode_withkey(ic,
880 		mtod(m, const struct ieee80211_frame_min *),
881 		rs->rs_keyix == HAL_RXKEYIX_INVALID ?
882 			IEEE80211_KEYIX_NONE : rs->rs_keyix);
883 	sc->sc_lastrs = rs;
884 
885 #ifdef	AH_SUPPORT_AR5416
886 	if (rs->rs_isaggr)
887 		sc->sc_stats.ast_rx_agg++;
888 #endif /* AH_SUPPORT_AR5416 */
889 
890 	if (ni != NULL) {
891 		/*
892 		 * Only punt packets for ampdu reorder processing for
893 		 * 11n nodes; net80211 enforces that M_AMPDU is only
894 		 * set for 11n nodes.
895 		 */
896 		if (ni->ni_flags & IEEE80211_NODE_HT)
897 			m->m_flags |= M_AMPDU;
898 
899 		/*
900 		 * Sending station is known, dispatch directly.
901 		 */
902 		type = ieee80211_input(ni, m, rs->rs_rssi, nf);
903 		ieee80211_free_node(ni);
904 		m = NULL;
905 		/*
906 		 * Arrange to update the last rx timestamp only for
907 		 * frames from our ap when operating in station mode.
908 		 * This assumes the rx key is always setup when
909 		 * associated.
910 		 */
911 		if (ic->ic_opmode == IEEE80211_M_STA &&
912 		    rs->rs_keyix != HAL_RXKEYIX_INVALID)
913 			is_good = 1;
914 	} else {
915 		type = ieee80211_input_all(ic, m, rs->rs_rssi, nf);
916 		m = NULL;
917 	}
918 
919 	/*
920 	 * At this point we have passed the frame up the stack; thus
921 	 * the mbuf is no longer ours.
922 	 */
923 
924 	/*
925 	 * Track rx rssi and do any rx antenna management.
926 	 */
927 	ATH_RSSI_LPF(sc->sc_halstats.ns_avgrssi, rs->rs_rssi);
928 	if (sc->sc_diversity) {
929 		/*
930 		 * When using fast diversity, change the default rx
931 		 * antenna if diversity chooses the other antenna 3
932 		 * times in a row.
933 		 */
934 		if (sc->sc_defant != rs->rs_antenna) {
935 			if (++sc->sc_rxotherant >= 3)
936 				ath_setdefantenna(sc, rs->rs_antenna);
937 		} else
938 			sc->sc_rxotherant = 0;
939 	}
940 
941 	/* Handle slow diversity if enabled */
942 	if (sc->sc_dolnadiv) {
943 		ath_lna_rx_comb_scan(sc, rs, ticks, hz);
944 	}
945 
946 	if (sc->sc_softled) {
947 		/*
948 		 * Blink for any data frame.  Otherwise do a
949 		 * heartbeat-style blink when idle.  The latter
950 		 * is mainly for station mode where we depend on
951 		 * periodic beacon frames to trigger the poll event.
952 		 */
953 		if (type == IEEE80211_FC0_TYPE_DATA) {
954 			const HAL_RATE_TABLE *rt = sc->sc_currates;
955 			ath_led_event(sc,
956 			    rt->rateCodeToIndex[rs->rs_rate]);
957 		} else if (ticks - sc->sc_ledevent >= sc->sc_ledidle)
958 			ath_led_event(sc, 0);
959 		}
960 rx_next:
961 	/*
962 	 * Debugging - complain if we didn't NULL the mbuf pointer
963 	 * here.
964 	 */
965 	if (m != NULL) {
966 		device_printf(sc->sc_dev,
967 		    "%s: mbuf %p should've been freed!\n",
968 		    __func__,
969 		    m);
970 	}
971 	return (is_good);
972 }
973 
974 #define	ATH_RX_MAX		128
975 
976 /*
977  * XXX TODO: break out the "get buffers" from "call ath_rx_pkt()" like
978  * the EDMA code does.
979  *
980  * XXX TODO: then, do all of the RX list management stuff inside
981  * ATH_RX_LOCK() so we don't end up potentially racing.  The EDMA
982  * code is doing it right.
983  */
984 static void
985 ath_rx_proc(struct ath_softc *sc, int resched)
986 {
987 #define	PA2DESC(_sc, _pa) \
988 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
989 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
990 	struct ath_buf *bf;
991 	struct ath_hal *ah = sc->sc_ah;
992 #ifdef IEEE80211_SUPPORT_SUPERG
993 	struct ieee80211com *ic = &sc->sc_ic;
994 #endif
995 	struct ath_desc *ds;
996 	struct ath_rx_status *rs;
997 	struct mbuf *m;
998 	int ngood;
999 	HAL_STATUS status;
1000 	int16_t nf;
1001 	u_int64_t tsf;
1002 	int npkts = 0;
1003 	int kickpcu = 0;
1004 	int ret;
1005 
1006 	/* XXX we must not hold the ATH_LOCK here */
1007 	ATH_UNLOCK_ASSERT(sc);
1008 	ATH_PCU_UNLOCK_ASSERT(sc);
1009 
1010 	ATH_PCU_LOCK(sc);
1011 	sc->sc_rxproc_cnt++;
1012 	kickpcu = sc->sc_kickpcu;
1013 	ATH_PCU_UNLOCK(sc);
1014 
1015 	ATH_LOCK(sc);
1016 	ath_power_set_power_state(sc, HAL_PM_AWAKE);
1017 	ATH_UNLOCK(sc);
1018 
1019 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: called\n", __func__);
1020 	ngood = 0;
1021 	nf = ath_hal_getchannoise(ah, sc->sc_curchan);
1022 	sc->sc_stats.ast_rx_noise = nf;
1023 	tsf = ath_hal_gettsf64(ah);
1024 	do {
1025 		/*
1026 		 * Don't process too many packets at a time; give the
1027 		 * TX thread time to also run - otherwise the TX
1028 		 * latency can jump by quite a bit, causing throughput
1029 		 * degredation.
1030 		 */
1031 		if (!kickpcu && npkts >= ATH_RX_MAX)
1032 			break;
1033 
1034 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1035 		if (sc->sc_rxslink && bf == NULL) {	/* NB: shouldn't happen */
1036 			device_printf(sc->sc_dev, "%s: no buffer!\n", __func__);
1037 			break;
1038 		} else if (bf == NULL) {
1039 			/*
1040 			 * End of List:
1041 			 * this can happen for non-self-linked RX chains
1042 			 */
1043 			sc->sc_stats.ast_rx_hitqueueend++;
1044 			break;
1045 		}
1046 		m = bf->bf_m;
1047 		if (m == NULL) {		/* NB: shouldn't happen */
1048 			/*
1049 			 * If mbuf allocation failed previously there
1050 			 * will be no mbuf; try again to re-populate it.
1051 			 */
1052 			/* XXX make debug msg */
1053 			device_printf(sc->sc_dev, "%s: no mbuf!\n", __func__);
1054 			TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1055 			goto rx_proc_next;
1056 		}
1057 		ds = bf->bf_desc;
1058 		if (ds->ds_link == bf->bf_daddr) {
1059 			/* NB: never process the self-linked entry at the end */
1060 			sc->sc_stats.ast_rx_hitqueueend++;
1061 			break;
1062 		}
1063 		/* XXX sync descriptor memory */
1064 		/*
1065 		 * Must provide the virtual address of the current
1066 		 * descriptor, the physical address, and the virtual
1067 		 * address of the next descriptor in the h/w chain.
1068 		 * This allows the HAL to look ahead to see if the
1069 		 * hardware is done with a descriptor by checking the
1070 		 * done bit in the following descriptor and the address
1071 		 * of the current descriptor the DMA engine is working
1072 		 * on.  All this is necessary because of our use of
1073 		 * a self-linked list to avoid rx overruns.
1074 		 */
1075 		rs = &bf->bf_status.ds_rxstat;
1076 		status = ath_hal_rxprocdesc(ah, ds,
1077 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1078 #ifdef ATH_DEBUG
1079 		if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
1080 			ath_printrxbuf(sc, bf, 0, status == HAL_OK);
1081 #endif
1082 
1083 #ifdef	ATH_DEBUG_ALQ
1084 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS))
1085 		    if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS,
1086 		    sc->sc_rx_statuslen, (char *) ds);
1087 #endif	/* ATH_DEBUG_ALQ */
1088 
1089 		if (status == HAL_EINPROGRESS)
1090 			break;
1091 
1092 		TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1093 		npkts++;
1094 
1095 		/*
1096 		 * Process a single frame.
1097 		 */
1098 		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_POSTREAD);
1099 		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
1100 		bf->bf_m = NULL;
1101 		if (ath_rx_pkt(sc, rs, status, tsf, nf, HAL_RX_QUEUE_HP, bf, m))
1102 			ngood++;
1103 rx_proc_next:
1104 		/*
1105 		 * If there's a holding buffer, insert that onto
1106 		 * the RX list; the hardware is now definitely not pointing
1107 		 * to it now.
1108 		 */
1109 		ret = 0;
1110 		if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf != NULL) {
1111 			TAILQ_INSERT_TAIL(&sc->sc_rxbuf,
1112 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf,
1113 			    bf_list);
1114 			ret = ath_rxbuf_init(sc,
1115 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf);
1116 		}
1117 		/*
1118 		 * Next, throw our buffer into the holding entry.  The hardware
1119 		 * may use the descriptor to read the link pointer before
1120 		 * DMAing the next descriptor in to write out a packet.
1121 		 */
1122 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = bf;
1123 	} while (ret == 0);
1124 
1125 	/* rx signal state monitoring */
1126 	ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
1127 	if (ngood)
1128 		sc->sc_lastrx = tsf;
1129 
1130 	ATH_KTR(sc, ATH_KTR_RXPROC, 2, "ath_rx_proc: npkts=%d, ngood=%d", npkts, ngood);
1131 	/* Queue DFS tasklet if needed */
1132 	if (resched && ath_dfs_tasklet_needed(sc, sc->sc_curchan))
1133 		taskqueue_enqueue(sc->sc_tq, &sc->sc_dfstask);
1134 
1135 	/*
1136 	 * Now that all the RX frames were handled that
1137 	 * need to be handled, kick the PCU if there's
1138 	 * been an RXEOL condition.
1139 	 */
1140 	if (resched && kickpcu) {
1141 		ATH_PCU_LOCK(sc);
1142 		ATH_KTR(sc, ATH_KTR_ERROR, 0, "ath_rx_proc: kickpcu");
1143 		device_printf(sc->sc_dev, "%s: kickpcu; handled %d packets\n",
1144 		    __func__, npkts);
1145 
1146 		/*
1147 		 * Go through the process of fully tearing down
1148 		 * the RX buffers and reinitialising them.
1149 		 *
1150 		 * There's a hardware bug that causes the RX FIFO
1151 		 * to get confused under certain conditions and
1152 		 * constantly write over the same frame, leading
1153 		 * the RX driver code here to get heavily confused.
1154 		 */
1155 		/*
1156 		 * XXX Has RX DMA stopped enough here to just call
1157 		 *     ath_startrecv()?
1158 		 * XXX Do we need to use the holding buffer to restart
1159 		 *     RX DMA by appending entries to the final
1160 		 *     descriptor?  Quite likely.
1161 		 */
1162 #if 1
1163 		ath_startrecv(sc);
1164 #else
1165 		/*
1166 		 * Disabled for now - it'd be nice to be able to do
1167 		 * this in order to limit the amount of CPU time spent
1168 		 * reinitialising the RX side (and thus minimise RX
1169 		 * drops) however there's a hardware issue that
1170 		 * causes things to get too far out of whack.
1171 		 */
1172 		/*
1173 		 * XXX can we hold the PCU lock here?
1174 		 * Are there any net80211 buffer calls involved?
1175 		 */
1176 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1177 		ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1178 		ath_hal_rxena(ah);		/* enable recv descriptors */
1179 		ath_mode_init(sc);		/* set filters, etc. */
1180 		ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
1181 #endif
1182 
1183 		ath_hal_intrset(ah, sc->sc_imask);
1184 		sc->sc_kickpcu = 0;
1185 		ATH_PCU_UNLOCK(sc);
1186 	}
1187 
1188 #ifdef IEEE80211_SUPPORT_SUPERG
1189 	if (resched)
1190 		ieee80211_ff_age_all(ic, 100);
1191 #endif
1192 
1193 	/*
1194 	 * Put the hardware to sleep again if we're done with it.
1195 	 */
1196 	ATH_LOCK(sc);
1197 	ath_power_restore_power_state(sc);
1198 	ATH_UNLOCK(sc);
1199 
1200 	/*
1201 	 * If we hit the maximum number of frames in this round,
1202 	 * reschedule for another immediate pass.  This gives
1203 	 * the TX and TX completion routines time to run, which
1204 	 * will reduce latency.
1205 	 */
1206 	if (npkts >= ATH_RX_MAX)
1207 		sc->sc_rx.recv_sched(sc, resched);
1208 
1209 	ATH_PCU_LOCK(sc);
1210 	sc->sc_rxproc_cnt--;
1211 	ATH_PCU_UNLOCK(sc);
1212 }
1213 #undef	PA2DESC
1214 #undef	ATH_RX_MAX
1215 
1216 /*
1217  * Only run the RX proc if it's not already running.
1218  * Since this may get run as part of the reset/flush path,
1219  * the task can't clash with an existing, running tasklet.
1220  */
1221 static void
1222 ath_legacy_rx_tasklet(void *arg, int npending)
1223 {
1224 	struct ath_softc *sc = arg;
1225 
1226 	ATH_KTR(sc, ATH_KTR_RXPROC, 1, "ath_rx_proc: pending=%d", npending);
1227 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: pending %u\n", __func__, npending);
1228 	ATH_PCU_LOCK(sc);
1229 	if (sc->sc_inreset_cnt > 0) {
1230 		device_printf(sc->sc_dev,
1231 		    "%s: sc_inreset_cnt > 0; skipping\n", __func__);
1232 		ATH_PCU_UNLOCK(sc);
1233 		return;
1234 	}
1235 	ATH_PCU_UNLOCK(sc);
1236 
1237 	ath_rx_proc(sc, 1);
1238 }
1239 
1240 static void
1241 ath_legacy_flushrecv(struct ath_softc *sc)
1242 {
1243 
1244 	ath_rx_proc(sc, 0);
1245 }
1246 
1247 static void
1248 ath_legacy_flush_rxpending(struct ath_softc *sc)
1249 {
1250 
1251 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1252 
1253 	if (sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending != NULL) {
1254 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending);
1255 		sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending = NULL;
1256 	}
1257 	if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending != NULL) {
1258 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending);
1259 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending = NULL;
1260 	}
1261 }
1262 
1263 static int
1264 ath_legacy_flush_rxholdbf(struct ath_softc *sc)
1265 {
1266 	struct ath_buf *bf;
1267 
1268 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1269 	/*
1270 	 * If there are RX holding buffers, free them here and return
1271 	 * them to the list.
1272 	 *
1273 	 * XXX should just verify that bf->bf_m is NULL, as it must
1274 	 * be at this point!
1275 	 */
1276 	bf = sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf;
1277 	if (bf != NULL) {
1278 		if (bf->bf_m != NULL)
1279 			m_freem(bf->bf_m);
1280 		bf->bf_m = NULL;
1281 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1282 		(void) ath_rxbuf_init(sc, bf);
1283 	}
1284 	sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = NULL;
1285 
1286 	bf = sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf;
1287 	if (bf != NULL) {
1288 		if (bf->bf_m != NULL)
1289 			m_freem(bf->bf_m);
1290 		bf->bf_m = NULL;
1291 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1292 		(void) ath_rxbuf_init(sc, bf);
1293 	}
1294 	sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf = NULL;
1295 
1296 	return (0);
1297 }
1298 
1299 /*
1300  * Disable the receive h/w in preparation for a reset.
1301  */
1302 static void
1303 ath_legacy_stoprecv(struct ath_softc *sc, int dodelay)
1304 {
1305 #define	PA2DESC(_sc, _pa) \
1306 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
1307 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
1308 	struct ath_hal *ah = sc->sc_ah;
1309 
1310 	ATH_RX_LOCK(sc);
1311 
1312 	ath_hal_stoppcurecv(ah);	/* disable PCU */
1313 	ath_hal_setrxfilter(ah, 0);	/* clear recv filter */
1314 	ath_hal_stopdmarecv(ah);	/* disable DMA engine */
1315 	/*
1316 	 * TODO: see if this particular DELAY() is required; it may be
1317 	 * masking some missing FIFO flush or DMA sync.
1318 	 */
1319 #if 0
1320 	if (dodelay)
1321 #endif
1322 		DELAY(3000);		/* 3ms is long enough for 1 frame */
1323 #ifdef ATH_DEBUG
1324 	if (sc->sc_debug & (ATH_DEBUG_RESET | ATH_DEBUG_FATAL)) {
1325 		struct ath_buf *bf;
1326 		u_int ix;
1327 
1328 		device_printf(sc->sc_dev,
1329 		    "%s: rx queue %p, link %p\n",
1330 		    __func__,
1331 		    (caddr_t)(uintptr_t) ath_hal_getrxbuf(ah, HAL_RX_QUEUE_HP),
1332 		    sc->sc_rxlink);
1333 		ix = 0;
1334 		TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1335 			struct ath_desc *ds = bf->bf_desc;
1336 			struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
1337 			HAL_STATUS status = ath_hal_rxprocdesc(ah, ds,
1338 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1339 			if (status == HAL_OK || (sc->sc_debug & ATH_DEBUG_FATAL))
1340 				ath_printrxbuf(sc, bf, ix, status == HAL_OK);
1341 			ix++;
1342 		}
1343 	}
1344 #endif
1345 
1346 	(void) ath_legacy_flush_rxpending(sc);
1347 	(void) ath_legacy_flush_rxholdbf(sc);
1348 
1349 	sc->sc_rxlink = NULL;		/* just in case */
1350 
1351 	ATH_RX_UNLOCK(sc);
1352 #undef PA2DESC
1353 }
1354 
1355 /*
1356  * XXX TODO: something was calling startrecv without calling
1357  * stoprecv.  Let's figure out what/why.  It was showing up
1358  * as a mbuf leak (rxpending) and ath_buf leak (holdbf.)
1359  */
1360 
1361 /*
1362  * Enable the receive h/w following a reset.
1363  */
1364 static int
1365 ath_legacy_startrecv(struct ath_softc *sc)
1366 {
1367 	struct ath_hal *ah = sc->sc_ah;
1368 	struct ath_buf *bf;
1369 
1370 	ATH_RX_LOCK(sc);
1371 
1372 	/*
1373 	 * XXX should verify these are already all NULL!
1374 	 */
1375 	sc->sc_rxlink = NULL;
1376 	(void) ath_legacy_flush_rxpending(sc);
1377 	(void) ath_legacy_flush_rxholdbf(sc);
1378 
1379 	/*
1380 	 * Re-chain all of the buffers in the RX buffer list.
1381 	 */
1382 	TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1383 		int error = ath_rxbuf_init(sc, bf);
1384 		if (error != 0) {
1385 			DPRINTF(sc, ATH_DEBUG_RECV,
1386 				"%s: ath_rxbuf_init failed %d\n",
1387 				__func__, error);
1388 			return error;
1389 		}
1390 	}
1391 
1392 	bf = TAILQ_FIRST(&sc->sc_rxbuf);
1393 	ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1394 	ath_hal_rxena(ah);		/* enable recv descriptors */
1395 	ath_mode_init(sc);		/* set filters, etc. */
1396 	ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
1397 
1398 	ATH_RX_UNLOCK(sc);
1399 	return 0;
1400 }
1401 
1402 static int
1403 ath_legacy_dma_rxsetup(struct ath_softc *sc)
1404 {
1405 	int error;
1406 
1407 	error = ath_descdma_setup(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
1408 	    "rx", sizeof(struct ath_desc), ath_rxbuf, 1);
1409 	if (error != 0)
1410 		return (error);
1411 
1412 	return (0);
1413 }
1414 
1415 static int
1416 ath_legacy_dma_rxteardown(struct ath_softc *sc)
1417 {
1418 
1419 	if (sc->sc_rxdma.dd_desc_len != 0)
1420 		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
1421 	return (0);
1422 }
1423 
1424 static void
1425 ath_legacy_recv_sched(struct ath_softc *sc, int dosched)
1426 {
1427 
1428 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1429 }
1430 
1431 static void
1432 ath_legacy_recv_sched_queue(struct ath_softc *sc, HAL_RX_QUEUE q,
1433     int dosched)
1434 {
1435 
1436 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1437 }
1438 
1439 void
1440 ath_recv_setup_legacy(struct ath_softc *sc)
1441 {
1442 
1443 	/* Sensible legacy defaults */
1444 	/*
1445 	 * XXX this should be changed to properly support the
1446 	 * exact RX descriptor size for each HAL.
1447 	 */
1448 	sc->sc_rx_statuslen = sizeof(struct ath_desc);
1449 
1450 	sc->sc_rx.recv_start = ath_legacy_startrecv;
1451 	sc->sc_rx.recv_stop = ath_legacy_stoprecv;
1452 	sc->sc_rx.recv_flush = ath_legacy_flushrecv;
1453 	sc->sc_rx.recv_tasklet = ath_legacy_rx_tasklet;
1454 	sc->sc_rx.recv_rxbuf_init = ath_legacy_rxbuf_init;
1455 
1456 	sc->sc_rx.recv_setup = ath_legacy_dma_rxsetup;
1457 	sc->sc_rx.recv_teardown = ath_legacy_dma_rxteardown;
1458 	sc->sc_rx.recv_sched = ath_legacy_recv_sched;
1459 	sc->sc_rx.recv_sched_queue = ath_legacy_recv_sched_queue;
1460 }
1461