xref: /freebsd/sys/dev/ath/if_ath_rx.c (revision bae28eaa8d26ddd67e9af51979f1a54599e9b3a8)
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 
115 #ifdef ATH_TX99_DIAG
116 #include <dev/ath/ath_tx99/ath_tx99.h>
117 #endif
118 
119 #ifdef	ATH_DEBUG_ALQ
120 #include <dev/ath/if_ath_alq.h>
121 #endif
122 
123 #include <dev/ath/if_ath_lna_div.h>
124 
125 /*
126  * Calculate the receive filter according to the
127  * operating mode and state:
128  *
129  * o always accept unicast, broadcast, and multicast traffic
130  * o accept PHY error frames when hardware doesn't have MIB support
131  *   to count and we need them for ANI (sta mode only until recently)
132  *   and we are not scanning (ANI is disabled)
133  *   NB: older hal's add rx filter bits out of sight and we need to
134  *	 blindly preserve them
135  * o probe request frames are accepted only when operating in
136  *   hostap, adhoc, mesh, or monitor modes
137  * o enable promiscuous mode
138  *   - when in monitor mode
139  *   - if interface marked PROMISC (assumes bridge setting is filtered)
140  * o accept beacons:
141  *   - when operating in station mode for collecting rssi data when
142  *     the station is otherwise quiet, or
143  *   - when operating in adhoc mode so the 802.11 layer creates
144  *     node table entries for peers,
145  *   - when scanning
146  *   - when doing s/w beacon miss (e.g. for ap+sta)
147  *   - when operating in ap mode in 11g to detect overlapping bss that
148  *     require protection
149  *   - when operating in mesh mode to detect neighbors
150  * o accept control frames:
151  *   - when in monitor mode
152  * XXX HT protection for 11n
153  */
154 u_int32_t
155 ath_calcrxfilter(struct ath_softc *sc)
156 {
157 	struct ieee80211com *ic = &sc->sc_ic;
158 	u_int32_t rfilt;
159 
160 	rfilt = HAL_RX_FILTER_UCAST | HAL_RX_FILTER_BCAST | HAL_RX_FILTER_MCAST;
161 	if (!sc->sc_needmib && !sc->sc_scanning)
162 		rfilt |= HAL_RX_FILTER_PHYERR;
163 	if (ic->ic_opmode != IEEE80211_M_STA)
164 		rfilt |= HAL_RX_FILTER_PROBEREQ;
165 	/* XXX ic->ic_monvaps != 0? */
166 	if (ic->ic_opmode == IEEE80211_M_MONITOR || ic->ic_promisc > 0)
167 		rfilt |= HAL_RX_FILTER_PROM;
168 
169 	/*
170 	 * Only listen to all beacons if we're scanning.
171 	 *
172 	 * Otherwise we only really need to hear beacons from
173 	 * our own BSSID.
174 	 */
175 	if (ic->ic_opmode == IEEE80211_M_STA ||
176 	    ic->ic_opmode == IEEE80211_M_IBSS || sc->sc_swbmiss) {
177 		if (sc->sc_do_mybeacon && ! sc->sc_scanning) {
178 			rfilt |= HAL_RX_FILTER_MYBEACON;
179 		} else { /* scanning, non-mybeacon chips */
180 			rfilt |= HAL_RX_FILTER_BEACON;
181 		}
182 	}
183 
184 	/*
185 	 * NB: We don't recalculate the rx filter when
186 	 * ic_protmode changes; otherwise we could do
187 	 * this only when ic_protmode != NONE.
188 	 */
189 	if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
190 	    IEEE80211_IS_CHAN_ANYG(ic->ic_curchan))
191 		rfilt |= HAL_RX_FILTER_BEACON;
192 
193 	/*
194 	 * Enable hardware PS-POLL RX only for hostap mode;
195 	 * STA mode sends PS-POLL frames but never
196 	 * receives them.
197 	 */
198 	if (ath_hal_getcapability(sc->sc_ah, HAL_CAP_PSPOLL,
199 	    0, NULL) == HAL_OK &&
200 	    ic->ic_opmode == IEEE80211_M_HOSTAP)
201 		rfilt |= HAL_RX_FILTER_PSPOLL;
202 
203 	if (sc->sc_nmeshvaps) {
204 		rfilt |= HAL_RX_FILTER_BEACON;
205 		if (sc->sc_hasbmatch)
206 			rfilt |= HAL_RX_FILTER_BSSID;
207 		else
208 			rfilt |= HAL_RX_FILTER_PROM;
209 	}
210 	if (ic->ic_opmode == IEEE80211_M_MONITOR)
211 		rfilt |= HAL_RX_FILTER_CONTROL;
212 
213 	/*
214 	 * Enable RX of compressed BAR frames only when doing
215 	 * 802.11n. Required for A-MPDU.
216 	 */
217 	if (IEEE80211_IS_CHAN_HT(ic->ic_curchan))
218 		rfilt |= HAL_RX_FILTER_COMPBAR;
219 
220 	/*
221 	 * Enable radar PHY errors if requested by the
222 	 * DFS module.
223 	 */
224 	if (sc->sc_dodfs)
225 		rfilt |= HAL_RX_FILTER_PHYRADAR;
226 
227 	/*
228 	 * Enable spectral PHY errors if requested by the
229 	 * spectral module.
230 	 */
231 	if (sc->sc_dospectral)
232 		rfilt |= HAL_RX_FILTER_PHYRADAR;
233 
234 	DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x, %s\n",
235 	    __func__, rfilt, ieee80211_opmode_name[ic->ic_opmode]);
236 	return rfilt;
237 }
238 
239 static int
240 ath_legacy_rxbuf_init(struct ath_softc *sc, struct ath_buf *bf)
241 {
242 	struct ath_hal *ah = sc->sc_ah;
243 	int error;
244 	struct mbuf *m;
245 	struct ath_desc *ds;
246 
247 	/* XXX TODO: ATH_RX_LOCK_ASSERT(sc); */
248 
249 	m = bf->bf_m;
250 	if (m == NULL) {
251 		/*
252 		 * NB: by assigning a page to the rx dma buffer we
253 		 * implicitly satisfy the Atheros requirement that
254 		 * this buffer be cache-line-aligned and sized to be
255 		 * multiple of the cache line size.  Not doing this
256 		 * causes weird stuff to happen (for the 5210 at least).
257 		 */
258 		m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
259 		if (m == NULL) {
260 			DPRINTF(sc, ATH_DEBUG_ANY,
261 				"%s: no mbuf/cluster\n", __func__);
262 			sc->sc_stats.ast_rx_nombuf++;
263 			return ENOMEM;
264 		}
265 		m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;
266 
267 		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat,
268 					     bf->bf_dmamap, m,
269 					     bf->bf_segs, &bf->bf_nseg,
270 					     BUS_DMA_NOWAIT);
271 		if (error != 0) {
272 			DPRINTF(sc, ATH_DEBUG_ANY,
273 			    "%s: bus_dmamap_load_mbuf_sg failed; error %d\n",
274 			    __func__, error);
275 			sc->sc_stats.ast_rx_busdma++;
276 			m_freem(m);
277 			return error;
278 		}
279 		KASSERT(bf->bf_nseg == 1,
280 			("multi-segment packet; nseg %u", bf->bf_nseg));
281 		bf->bf_m = m;
282 	}
283 	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREREAD);
284 
285 	/*
286 	 * Setup descriptors.  For receive we always terminate
287 	 * the descriptor list with a self-linked entry so we'll
288 	 * not get overrun under high load (as can happen with a
289 	 * 5212 when ANI processing enables PHY error frames).
290 	 *
291 	 * To insure the last descriptor is self-linked we create
292 	 * each descriptor as self-linked and add it to the end.  As
293 	 * each additional descriptor is added the previous self-linked
294 	 * entry is ``fixed'' naturally.  This should be safe even
295 	 * if DMA is happening.  When processing RX interrupts we
296 	 * never remove/process the last, self-linked, entry on the
297 	 * descriptor list.  This insures the hardware always has
298 	 * someplace to write a new frame.
299 	 */
300 	/*
301 	 * 11N: we can no longer afford to self link the last descriptor.
302 	 * MAC acknowledges BA status as long as it copies frames to host
303 	 * buffer (or rx fifo). This can incorrectly acknowledge packets
304 	 * to a sender if last desc is self-linked.
305 	 */
306 	ds = bf->bf_desc;
307 	if (sc->sc_rxslink)
308 		ds->ds_link = bf->bf_daddr;	/* link to self */
309 	else
310 		ds->ds_link = 0;		/* terminate the list */
311 	ds->ds_data = bf->bf_segs[0].ds_addr;
312 	ath_hal_setuprxdesc(ah, ds
313 		, m->m_len		/* buffer size */
314 		, 0
315 	);
316 
317 	if (sc->sc_rxlink != NULL)
318 		*sc->sc_rxlink = bf->bf_daddr;
319 	sc->sc_rxlink = &ds->ds_link;
320 	return 0;
321 }
322 
323 /*
324  * Intercept management frames to collect beacon rssi data
325  * and to do ibss merges.
326  */
327 void
328 ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
329 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
330 {
331 	struct ieee80211vap *vap = ni->ni_vap;
332 	struct ath_softc *sc = vap->iv_ic->ic_softc;
333 	uint64_t tsf_beacon_old, tsf_beacon;
334 	uint64_t nexttbtt;
335 	int64_t tsf_delta;
336 	int32_t tsf_delta_bmiss;
337 	int32_t tsf_remainder;
338 	uint64_t tsf_beacon_target;
339 	int tsf_intval;
340 
341 	tsf_beacon_old = ((uint64_t) LE_READ_4(ni->ni_tstamp.data + 4)) << 32;
342 	tsf_beacon_old |= LE_READ_4(ni->ni_tstamp.data);
343 
344 #define	TU_TO_TSF(_tu)	(((u_int64_t)(_tu)) << 10)
345 	tsf_intval = 1;
346 	if (ni->ni_intval > 0) {
347 		tsf_intval = TU_TO_TSF(ni->ni_intval);
348 	}
349 #undef	TU_TO_TSF
350 
351 	/*
352 	 * Call up first so subsequent work can use information
353 	 * potentially stored in the node (e.g. for ibss merge).
354 	 */
355 	ATH_VAP(vap)->av_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
356 	switch (subtype) {
357 	case IEEE80211_FC0_SUBTYPE_BEACON:
358 		/* update rssi statistics for use by the hal */
359 		/* XXX unlocked check against vap->iv_bss? */
360 		ATH_RSSI_LPF(sc->sc_halstats.ns_avgbrssi, rssi);
361 
362 		tsf_beacon = ((uint64_t) LE_READ_4(ni->ni_tstamp.data + 4)) << 32;
363 		tsf_beacon |= LE_READ_4(ni->ni_tstamp.data);
364 
365 		nexttbtt = ath_hal_getnexttbtt(sc->sc_ah);
366 
367 		/*
368 		 * Let's calculate the delta and remainder, so we can see
369 		 * if the beacon timer from the AP is varying by more than
370 		 * a few TU.  (Which would be a huge, huge problem.)
371 		 */
372 		tsf_delta = (long long) tsf_beacon - (long long) tsf_beacon_old;
373 
374 		tsf_delta_bmiss = tsf_delta / tsf_intval;
375 
376 		/*
377 		 * If our delta is greater than half the beacon interval,
378 		 * let's round the bmiss value up to the next beacon
379 		 * interval.  Ie, we're running really, really early
380 		 * on the next beacon.
381 		 */
382 		if (tsf_delta % tsf_intval > (tsf_intval / 2))
383 			tsf_delta_bmiss ++;
384 
385 		tsf_beacon_target = tsf_beacon_old +
386 		    (((unsigned long long) tsf_delta_bmiss) * (long long) tsf_intval);
387 
388 		/*
389 		 * The remainder using '%' is between 0 .. intval-1.
390 		 * If we're actually running too fast, then the remainder
391 		 * will be some large number just under intval-1.
392 		 * So we need to look at whether we're running
393 		 * before or after the target beacon interval
394 		 * and if we are, modify how we do the remainder
395 		 * calculation.
396 		 */
397 		if (tsf_beacon < tsf_beacon_target) {
398 			tsf_remainder =
399 			    -(tsf_intval - ((tsf_beacon - tsf_beacon_old) % tsf_intval));
400 		} else {
401 			tsf_remainder = (tsf_beacon - tsf_beacon_old) % tsf_intval;
402 		}
403 
404 		DPRINTF(sc, ATH_DEBUG_BEACON, "%s: old_tsf=%llu, new_tsf=%llu, target_tsf=%llu, delta=%lld, bmiss=%d, remainder=%d\n",
405 		    __func__,
406 		    (unsigned long long) tsf_beacon_old,
407 		    (unsigned long long) tsf_beacon,
408 		    (unsigned long long) tsf_beacon_target,
409 		    (long long) tsf_delta,
410 		    tsf_delta_bmiss,
411 		    tsf_remainder);
412 
413 		DPRINTF(sc, ATH_DEBUG_BEACON, "%s: tsf=%llu, nexttbtt=%llu, delta=%d\n",
414 		    __func__,
415 		    (unsigned long long) tsf_beacon,
416 		    (unsigned long long) nexttbtt,
417 		    (int32_t) tsf_beacon - (int32_t) nexttbtt + tsf_intval);
418 
419 		if (sc->sc_syncbeacon &&
420 		    ni == vap->iv_bss &&
421 		    (vap->iv_state == IEEE80211_S_RUN || vap->iv_state == IEEE80211_S_SLEEP)) {
422 			DPRINTF(sc, ATH_DEBUG_BEACON,
423 			    "%s: syncbeacon=1; syncing\n",
424 			    __func__);
425 			/*
426 			 * Resync beacon timers using the tsf of the beacon
427 			 * frame we just received.
428 			 */
429 			ath_beacon_config(sc, vap);
430 			sc->sc_syncbeacon = 0;
431 		}
432 
433 
434 		/* fall thru... */
435 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
436 		if (vap->iv_opmode == IEEE80211_M_IBSS &&
437 		    vap->iv_state == IEEE80211_S_RUN) {
438 			uint32_t rstamp = sc->sc_lastrs->rs_tstamp;
439 			uint64_t tsf = ath_extend_tsf(sc, rstamp,
440 				ath_hal_gettsf64(sc->sc_ah));
441 			/*
442 			 * Handle ibss merge as needed; check the tsf on the
443 			 * frame before attempting the merge.  The 802.11 spec
444 			 * says the station should change it's bssid to match
445 			 * the oldest station with the same ssid, where oldest
446 			 * is determined by the tsf.  Note that hardware
447 			 * reconfiguration happens through callback to
448 			 * ath_newstate as the state machine will go from
449 			 * RUN -> RUN when this happens.
450 			 */
451 			if (le64toh(ni->ni_tstamp.tsf) >= tsf) {
452 				DPRINTF(sc, ATH_DEBUG_STATE,
453 				    "ibss merge, rstamp %u tsf %ju "
454 				    "tstamp %ju\n", rstamp, (uintmax_t)tsf,
455 				    (uintmax_t)ni->ni_tstamp.tsf);
456 				(void) ieee80211_ibss_merge(ni);
457 			}
458 		}
459 		break;
460 	}
461 }
462 
463 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
464 static void
465 ath_rx_tap_vendor(struct ath_softc *sc, struct mbuf *m,
466     const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
467 {
468 
469 	/* Fill in the extension bitmap */
470 	sc->sc_rx_th.wr_ext_bitmap = htole32(1 << ATH_RADIOTAP_VENDOR_HEADER);
471 
472 	/* Fill in the vendor header */
473 	sc->sc_rx_th.wr_vh.vh_oui[0] = 0x7f;
474 	sc->sc_rx_th.wr_vh.vh_oui[1] = 0x03;
475 	sc->sc_rx_th.wr_vh.vh_oui[2] = 0x00;
476 
477 	/* XXX what should this be? */
478 	sc->sc_rx_th.wr_vh.vh_sub_ns = 0;
479 	sc->sc_rx_th.wr_vh.vh_skip_len =
480 	    htole16(sizeof(struct ath_radiotap_vendor_hdr));
481 
482 	/* General version info */
483 	sc->sc_rx_th.wr_v.vh_version = 1;
484 
485 	sc->sc_rx_th.wr_v.vh_rx_chainmask = sc->sc_rxchainmask;
486 
487 	/* rssi */
488 	sc->sc_rx_th.wr_v.rssi_ctl[0] = rs->rs_rssi_ctl[0];
489 	sc->sc_rx_th.wr_v.rssi_ctl[1] = rs->rs_rssi_ctl[1];
490 	sc->sc_rx_th.wr_v.rssi_ctl[2] = rs->rs_rssi_ctl[2];
491 	sc->sc_rx_th.wr_v.rssi_ext[0] = rs->rs_rssi_ext[0];
492 	sc->sc_rx_th.wr_v.rssi_ext[1] = rs->rs_rssi_ext[1];
493 	sc->sc_rx_th.wr_v.rssi_ext[2] = rs->rs_rssi_ext[2];
494 
495 	/* evm */
496 	sc->sc_rx_th.wr_v.evm[0] = rs->rs_evm0;
497 	sc->sc_rx_th.wr_v.evm[1] = rs->rs_evm1;
498 	sc->sc_rx_th.wr_v.evm[2] = rs->rs_evm2;
499 	/* These are only populated from the AR9300 or later */
500 	sc->sc_rx_th.wr_v.evm[3] = rs->rs_evm3;
501 	sc->sc_rx_th.wr_v.evm[4] = rs->rs_evm4;
502 
503 	/* direction */
504 	sc->sc_rx_th.wr_v.vh_flags = ATH_VENDOR_PKT_RX;
505 
506 	/* RX rate */
507 	sc->sc_rx_th.wr_v.vh_rx_hwrate = rs->rs_rate;
508 
509 	/* RX flags */
510 	sc->sc_rx_th.wr_v.vh_rs_flags = rs->rs_flags;
511 
512 	if (rs->rs_isaggr)
513 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_ISAGGR;
514 	if (rs->rs_moreaggr)
515 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_MOREAGGR;
516 
517 	/* phyerr info */
518 	if (rs->rs_status & HAL_RXERR_PHY) {
519 		sc->sc_rx_th.wr_v.vh_phyerr_code = rs->rs_phyerr;
520 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_RXPHYERR;
521 	} else {
522 		sc->sc_rx_th.wr_v.vh_phyerr_code = 0xff;
523 	}
524 	sc->sc_rx_th.wr_v.vh_rs_status = rs->rs_status;
525 	sc->sc_rx_th.wr_v.vh_rssi = rs->rs_rssi;
526 }
527 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
528 
529 static void
530 ath_rx_tap(struct ath_softc *sc, struct mbuf *m,
531 	const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
532 {
533 #define	CHAN_HT20	htole32(IEEE80211_CHAN_HT20)
534 #define	CHAN_HT40U	htole32(IEEE80211_CHAN_HT40U)
535 #define	CHAN_HT40D	htole32(IEEE80211_CHAN_HT40D)
536 #define	CHAN_HT		(CHAN_HT20|CHAN_HT40U|CHAN_HT40D)
537 	const HAL_RATE_TABLE *rt;
538 	uint8_t rix;
539 
540 	rt = sc->sc_currates;
541 	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
542 	rix = rt->rateCodeToIndex[rs->rs_rate];
543 	sc->sc_rx_th.wr_rate = sc->sc_hwmap[rix].ieeerate;
544 	sc->sc_rx_th.wr_flags = sc->sc_hwmap[rix].rxflags;
545 #ifdef AH_SUPPORT_AR5416
546 	sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT;
547 	if (rs->rs_status & HAL_RXERR_PHY) {
548 		/*
549 		 * PHY error - make sure the channel flags
550 		 * reflect the actual channel configuration,
551 		 * not the received frame.
552 		 */
553 		if (IEEE80211_IS_CHAN_HT40U(sc->sc_curchan))
554 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
555 		else if (IEEE80211_IS_CHAN_HT40D(sc->sc_curchan))
556 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
557 		else if (IEEE80211_IS_CHAN_HT20(sc->sc_curchan))
558 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
559 	} else if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) {	/* HT rate */
560 		struct ieee80211com *ic = &sc->sc_ic;
561 
562 		if ((rs->rs_flags & HAL_RX_2040) == 0)
563 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
564 		else if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan))
565 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
566 		else
567 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
568 		if ((rs->rs_flags & HAL_RX_GI) == 0)
569 			sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_SHORTGI;
570 	}
571 
572 #endif
573 	sc->sc_rx_th.wr_tsf = htole64(ath_extend_tsf(sc, rs->rs_tstamp, tsf));
574 	if (rs->rs_status & HAL_RXERR_CRC)
575 		sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_BADFCS;
576 	/* XXX propagate other error flags from descriptor */
577 	sc->sc_rx_th.wr_antnoise = nf;
578 	sc->sc_rx_th.wr_antsignal = nf + rs->rs_rssi;
579 	sc->sc_rx_th.wr_antenna = rs->rs_antenna;
580 #undef CHAN_HT
581 #undef CHAN_HT20
582 #undef CHAN_HT40U
583 #undef CHAN_HT40D
584 }
585 
586 static void
587 ath_handle_micerror(struct ieee80211com *ic,
588 	struct ieee80211_frame *wh, int keyix)
589 {
590 	struct ieee80211_node *ni;
591 
592 	/* XXX recheck MIC to deal w/ chips that lie */
593 	/* XXX discard MIC errors on !data frames */
594 	ni = ieee80211_find_rxnode(ic, (const struct ieee80211_frame_min *) wh);
595 	if (ni != NULL) {
596 		ieee80211_notify_michael_failure(ni->ni_vap, wh, keyix);
597 		ieee80211_free_node(ni);
598 	}
599 }
600 
601 /*
602  * Process a single packet.
603  *
604  * The mbuf must already be synced, unmapped and removed from bf->bf_m
605  * by this stage.
606  *
607  * The mbuf must be consumed by this routine - either passed up the
608  * net80211 stack, put on the holding queue, or freed.
609  */
610 int
611 ath_rx_pkt(struct ath_softc *sc, struct ath_rx_status *rs, HAL_STATUS status,
612     uint64_t tsf, int nf, HAL_RX_QUEUE qtype, struct ath_buf *bf,
613     struct mbuf *m)
614 {
615 	uint64_t rstamp;
616 	int len, type;
617 	struct ieee80211com *ic = &sc->sc_ic;
618 	struct ieee80211_node *ni;
619 	int is_good = 0;
620 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
621 
622 	/*
623 	 * Calculate the correct 64 bit TSF given
624 	 * the TSF64 register value and rs_tstamp.
625 	 */
626 	rstamp = ath_extend_tsf(sc, rs->rs_tstamp, tsf);
627 
628 	/* These aren't specifically errors */
629 #ifdef	AH_SUPPORT_AR5416
630 	if (rs->rs_flags & HAL_RX_GI)
631 		sc->sc_stats.ast_rx_halfgi++;
632 	if (rs->rs_flags & HAL_RX_2040)
633 		sc->sc_stats.ast_rx_2040++;
634 	if (rs->rs_flags & HAL_RX_DELIM_CRC_PRE)
635 		sc->sc_stats.ast_rx_pre_crc_err++;
636 	if (rs->rs_flags & HAL_RX_DELIM_CRC_POST)
637 		sc->sc_stats.ast_rx_post_crc_err++;
638 	if (rs->rs_flags & HAL_RX_DECRYPT_BUSY)
639 		sc->sc_stats.ast_rx_decrypt_busy_err++;
640 	if (rs->rs_flags & HAL_RX_HI_RX_CHAIN)
641 		sc->sc_stats.ast_rx_hi_rx_chain++;
642 	if (rs->rs_flags & HAL_RX_STBC)
643 		sc->sc_stats.ast_rx_stbc++;
644 #endif /* AH_SUPPORT_AR5416 */
645 
646 	if (rs->rs_status != 0) {
647 		if (rs->rs_status & HAL_RXERR_CRC)
648 			sc->sc_stats.ast_rx_crcerr++;
649 		if (rs->rs_status & HAL_RXERR_FIFO)
650 			sc->sc_stats.ast_rx_fifoerr++;
651 		if (rs->rs_status & HAL_RXERR_PHY) {
652 			sc->sc_stats.ast_rx_phyerr++;
653 			/* Process DFS radar events */
654 			if ((rs->rs_phyerr == HAL_PHYERR_RADAR) ||
655 			    (rs->rs_phyerr == HAL_PHYERR_FALSE_RADAR_EXT)) {
656 				/* Now pass it to the radar processing code */
657 				ath_dfs_process_phy_err(sc, m, rstamp, rs);
658 			}
659 
660 			/* Be suitably paranoid about receiving phy errors out of the stats array bounds */
661 			if (rs->rs_phyerr < 64)
662 				sc->sc_stats.ast_rx_phy[rs->rs_phyerr]++;
663 			goto rx_error;	/* NB: don't count in ierrors */
664 		}
665 		if (rs->rs_status & HAL_RXERR_DECRYPT) {
666 			/*
667 			 * Decrypt error.  If the error occurred
668 			 * because there was no hardware key, then
669 			 * let the frame through so the upper layers
670 			 * can process it.  This is necessary for 5210
671 			 * parts which have no way to setup a ``clear''
672 			 * key cache entry.
673 			 *
674 			 * XXX do key cache faulting
675 			 */
676 			if (rs->rs_keyix == HAL_RXKEYIX_INVALID)
677 				goto rx_accept;
678 			sc->sc_stats.ast_rx_badcrypt++;
679 		}
680 		/*
681 		 * Similar as above - if the failure was a keymiss
682 		 * just punt it up to the upper layers for now.
683 		 */
684 		if (rs->rs_status & HAL_RXERR_KEYMISS) {
685 			sc->sc_stats.ast_rx_keymiss++;
686 			goto rx_accept;
687 		}
688 		if (rs->rs_status & HAL_RXERR_MIC) {
689 			sc->sc_stats.ast_rx_badmic++;
690 			/*
691 			 * Do minimal work required to hand off
692 			 * the 802.11 header for notification.
693 			 */
694 			/* XXX frag's and qos frames */
695 			len = rs->rs_datalen;
696 			if (len >= sizeof (struct ieee80211_frame)) {
697 				ath_handle_micerror(ic,
698 				    mtod(m, struct ieee80211_frame *),
699 				    sc->sc_splitmic ?
700 					rs->rs_keyix-32 : rs->rs_keyix);
701 			}
702 		}
703 		counter_u64_add(ic->ic_ierrors, 1);
704 rx_error:
705 		/*
706 		 * Cleanup any pending partial frame.
707 		 */
708 		if (re->m_rxpending != NULL) {
709 			m_freem(re->m_rxpending);
710 			re->m_rxpending = NULL;
711 		}
712 		/*
713 		 * When a tap is present pass error frames
714 		 * that have been requested.  By default we
715 		 * pass decrypt+mic errors but others may be
716 		 * interesting (e.g. crc).
717 		 */
718 		if (ieee80211_radiotap_active(ic) &&
719 		    (rs->rs_status & sc->sc_monpass)) {
720 			/* NB: bpf needs the mbuf length setup */
721 			len = rs->rs_datalen;
722 			m->m_pkthdr.len = m->m_len = len;
723 			ath_rx_tap(sc, m, rs, rstamp, nf);
724 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
725 			ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
726 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
727 			ieee80211_radiotap_rx_all(ic, m);
728 		}
729 		/* XXX pass MIC errors up for s/w reclaculation */
730 		m_freem(m); m = NULL;
731 		goto rx_next;
732 	}
733 rx_accept:
734 	len = rs->rs_datalen;
735 	m->m_len = len;
736 
737 	if (rs->rs_more) {
738 		/*
739 		 * Frame spans multiple descriptors; save
740 		 * it for the next completed descriptor, it
741 		 * will be used to construct a jumbogram.
742 		 */
743 		if (re->m_rxpending != NULL) {
744 			/* NB: max frame size is currently 2 clusters */
745 			sc->sc_stats.ast_rx_toobig++;
746 			m_freem(re->m_rxpending);
747 		}
748 		m->m_pkthdr.len = len;
749 		re->m_rxpending = m;
750 		m = NULL;
751 		goto rx_next;
752 	} else if (re->m_rxpending != NULL) {
753 		/*
754 		 * This is the second part of a jumbogram,
755 		 * chain it to the first mbuf, adjust the
756 		 * frame length, and clear the rxpending state.
757 		 */
758 		re->m_rxpending->m_next = m;
759 		re->m_rxpending->m_pkthdr.len += len;
760 		m = re->m_rxpending;
761 		re->m_rxpending = NULL;
762 	} else {
763 		/*
764 		 * Normal single-descriptor receive; setup packet length.
765 		 */
766 		m->m_pkthdr.len = len;
767 	}
768 
769 	/*
770 	 * Validate rs->rs_antenna.
771 	 *
772 	 * Some users w/ AR9285 NICs have reported crashes
773 	 * here because rs_antenna field is bogusly large.
774 	 * Let's enforce the maximum antenna limit of 8
775 	 * (and it shouldn't be hard coded, but that's a
776 	 * separate problem) and if there's an issue, print
777 	 * out an error and adjust rs_antenna to something
778 	 * sensible.
779 	 *
780 	 * This code should be removed once the actual
781 	 * root cause of the issue has been identified.
782 	 * For example, it may be that the rs_antenna
783 	 * field is only valid for the lsat frame of
784 	 * an aggregate and it just happens that it is
785 	 * "mostly" right. (This is a general statement -
786 	 * the majority of the statistics are only valid
787 	 * for the last frame in an aggregate.
788 	 */
789 	if (rs->rs_antenna > 7) {
790 		device_printf(sc->sc_dev, "%s: rs_antenna > 7 (%d)\n",
791 		    __func__, rs->rs_antenna);
792 #ifdef	ATH_DEBUG
793 		ath_printrxbuf(sc, bf, 0, status == HAL_OK);
794 #endif /* ATH_DEBUG */
795 		rs->rs_antenna = 0;	/* XXX better than nothing */
796 	}
797 
798 	/*
799 	 * If this is an AR9285/AR9485, then the receive and LNA
800 	 * configuration is stored in RSSI[2] / EXTRSSI[2].
801 	 * We can extract this out to build a much better
802 	 * receive antenna profile.
803 	 *
804 	 * Yes, this just blurts over the above RX antenna field
805 	 * for now.  It's fine, the AR9285 doesn't really use
806 	 * that.
807 	 *
808 	 * Later on we should store away the fine grained LNA
809 	 * information and keep separate counters just for
810 	 * that.  It'll help when debugging the AR9285/AR9485
811 	 * combined diversity code.
812 	 */
813 	if (sc->sc_rx_lnamixer) {
814 		rs->rs_antenna = 0;
815 
816 		/* Bits 0:1 - the LNA configuration used */
817 		rs->rs_antenna |=
818 		    ((rs->rs_rssi_ctl[2] & HAL_RX_LNA_CFG_USED)
819 		      >> HAL_RX_LNA_CFG_USED_S);
820 
821 		/* Bit 2 - the external RX antenna switch */
822 		if (rs->rs_rssi_ctl[2] & HAL_RX_LNA_EXTCFG)
823 			rs->rs_antenna |= 0x4;
824 	}
825 
826 	sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;
827 
828 	/*
829 	 * Populate the rx status block.  When there are bpf
830 	 * listeners we do the additional work to provide
831 	 * complete status.  Otherwise we fill in only the
832 	 * material required by ieee80211_input.  Note that
833 	 * noise setting is filled in above.
834 	 */
835 	if (ieee80211_radiotap_active(ic)) {
836 		ath_rx_tap(sc, m, rs, rstamp, nf);
837 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
838 		ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
839 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
840 	}
841 
842 	/*
843 	 * From this point on we assume the frame is at least
844 	 * as large as ieee80211_frame_min; verify that.
845 	 */
846 	if (len < IEEE80211_MIN_LEN) {
847 		if (!ieee80211_radiotap_active(ic)) {
848 			DPRINTF(sc, ATH_DEBUG_RECV,
849 			    "%s: short packet %d\n", __func__, len);
850 			sc->sc_stats.ast_rx_tooshort++;
851 		} else {
852 			/* NB: in particular this captures ack's */
853 			ieee80211_radiotap_rx_all(ic, m);
854 		}
855 		m_freem(m); m = NULL;
856 		goto rx_next;
857 	}
858 
859 	if (IFF_DUMPPKTS(sc, ATH_DEBUG_RECV)) {
860 		const HAL_RATE_TABLE *rt = sc->sc_currates;
861 		uint8_t rix = rt->rateCodeToIndex[rs->rs_rate];
862 
863 		ieee80211_dump_pkt(ic, mtod(m, caddr_t), len,
864 		    sc->sc_hwmap[rix].ieeerate, rs->rs_rssi);
865 	}
866 
867 	m_adj(m, -IEEE80211_CRC_LEN);
868 
869 	/*
870 	 * Locate the node for sender, track state, and then
871 	 * pass the (referenced) node up to the 802.11 layer
872 	 * for its use.
873 	 */
874 	ni = ieee80211_find_rxnode_withkey(ic,
875 		mtod(m, const struct ieee80211_frame_min *),
876 		rs->rs_keyix == HAL_RXKEYIX_INVALID ?
877 			IEEE80211_KEYIX_NONE : rs->rs_keyix);
878 	sc->sc_lastrs = rs;
879 
880 #ifdef	AH_SUPPORT_AR5416
881 	if (rs->rs_isaggr)
882 		sc->sc_stats.ast_rx_agg++;
883 #endif /* AH_SUPPORT_AR5416 */
884 
885 	if (ni != NULL) {
886 		/*
887 		 * Only punt packets for ampdu reorder processing for
888 		 * 11n nodes; net80211 enforces that M_AMPDU is only
889 		 * set for 11n nodes.
890 		 */
891 		if (ni->ni_flags & IEEE80211_NODE_HT)
892 			m->m_flags |= M_AMPDU;
893 
894 		/*
895 		 * Sending station is known, dispatch directly.
896 		 */
897 		type = ieee80211_input(ni, m, rs->rs_rssi, nf);
898 		ieee80211_free_node(ni);
899 		m = NULL;
900 		/*
901 		 * Arrange to update the last rx timestamp only for
902 		 * frames from our ap when operating in station mode.
903 		 * This assumes the rx key is always setup when
904 		 * associated.
905 		 */
906 		if (ic->ic_opmode == IEEE80211_M_STA &&
907 		    rs->rs_keyix != HAL_RXKEYIX_INVALID)
908 			is_good = 1;
909 	} else {
910 		type = ieee80211_input_all(ic, m, rs->rs_rssi, nf);
911 		m = NULL;
912 	}
913 
914 	/*
915 	 * At this point we have passed the frame up the stack; thus
916 	 * the mbuf is no longer ours.
917 	 */
918 
919 	/*
920 	 * Track rx rssi and do any rx antenna management.
921 	 */
922 	ATH_RSSI_LPF(sc->sc_halstats.ns_avgrssi, rs->rs_rssi);
923 	if (sc->sc_diversity) {
924 		/*
925 		 * When using fast diversity, change the default rx
926 		 * antenna if diversity chooses the other antenna 3
927 		 * times in a row.
928 		 */
929 		if (sc->sc_defant != rs->rs_antenna) {
930 			if (++sc->sc_rxotherant >= 3)
931 				ath_setdefantenna(sc, rs->rs_antenna);
932 		} else
933 			sc->sc_rxotherant = 0;
934 	}
935 
936 	/* Handle slow diversity if enabled */
937 	if (sc->sc_dolnadiv) {
938 		ath_lna_rx_comb_scan(sc, rs, ticks, hz);
939 	}
940 
941 	if (sc->sc_softled) {
942 		/*
943 		 * Blink for any data frame.  Otherwise do a
944 		 * heartbeat-style blink when idle.  The latter
945 		 * is mainly for station mode where we depend on
946 		 * periodic beacon frames to trigger the poll event.
947 		 */
948 		if (type == IEEE80211_FC0_TYPE_DATA) {
949 			const HAL_RATE_TABLE *rt = sc->sc_currates;
950 			ath_led_event(sc,
951 			    rt->rateCodeToIndex[rs->rs_rate]);
952 		} else if (ticks - sc->sc_ledevent >= sc->sc_ledidle)
953 			ath_led_event(sc, 0);
954 		}
955 rx_next:
956 	/*
957 	 * Debugging - complain if we didn't NULL the mbuf pointer
958 	 * here.
959 	 */
960 	if (m != NULL) {
961 		device_printf(sc->sc_dev,
962 		    "%s: mbuf %p should've been freed!\n",
963 		    __func__,
964 		    m);
965 	}
966 	return (is_good);
967 }
968 
969 #define	ATH_RX_MAX		128
970 
971 /*
972  * XXX TODO: break out the "get buffers" from "call ath_rx_pkt()" like
973  * the EDMA code does.
974  *
975  * XXX TODO: then, do all of the RX list management stuff inside
976  * ATH_RX_LOCK() so we don't end up potentially racing.  The EDMA
977  * code is doing it right.
978  */
979 static void
980 ath_rx_proc(struct ath_softc *sc, int resched)
981 {
982 #define	PA2DESC(_sc, _pa) \
983 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
984 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
985 	struct ath_buf *bf;
986 	struct ath_hal *ah = sc->sc_ah;
987 #ifdef IEEE80211_SUPPORT_SUPERG
988 	struct ieee80211com *ic = &sc->sc_ic;
989 #endif
990 	struct ath_desc *ds;
991 	struct ath_rx_status *rs;
992 	struct mbuf *m;
993 	int ngood;
994 	HAL_STATUS status;
995 	int16_t nf;
996 	u_int64_t tsf;
997 	int npkts = 0;
998 	int kickpcu = 0;
999 	int ret;
1000 
1001 	/* XXX we must not hold the ATH_LOCK here */
1002 	ATH_UNLOCK_ASSERT(sc);
1003 	ATH_PCU_UNLOCK_ASSERT(sc);
1004 
1005 	ATH_PCU_LOCK(sc);
1006 	sc->sc_rxproc_cnt++;
1007 	kickpcu = sc->sc_kickpcu;
1008 	ATH_PCU_UNLOCK(sc);
1009 
1010 	ATH_LOCK(sc);
1011 	ath_power_set_power_state(sc, HAL_PM_AWAKE);
1012 	ATH_UNLOCK(sc);
1013 
1014 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: called\n", __func__);
1015 	ngood = 0;
1016 	nf = ath_hal_getchannoise(ah, sc->sc_curchan);
1017 	sc->sc_stats.ast_rx_noise = nf;
1018 	tsf = ath_hal_gettsf64(ah);
1019 	do {
1020 		/*
1021 		 * Don't process too many packets at a time; give the
1022 		 * TX thread time to also run - otherwise the TX
1023 		 * latency can jump by quite a bit, causing throughput
1024 		 * degredation.
1025 		 */
1026 		if (!kickpcu && npkts >= ATH_RX_MAX)
1027 			break;
1028 
1029 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1030 		if (sc->sc_rxslink && bf == NULL) {	/* NB: shouldn't happen */
1031 			device_printf(sc->sc_dev, "%s: no buffer!\n", __func__);
1032 			break;
1033 		} else if (bf == NULL) {
1034 			/*
1035 			 * End of List:
1036 			 * this can happen for non-self-linked RX chains
1037 			 */
1038 			sc->sc_stats.ast_rx_hitqueueend++;
1039 			break;
1040 		}
1041 		m = bf->bf_m;
1042 		if (m == NULL) {		/* NB: shouldn't happen */
1043 			/*
1044 			 * If mbuf allocation failed previously there
1045 			 * will be no mbuf; try again to re-populate it.
1046 			 */
1047 			/* XXX make debug msg */
1048 			device_printf(sc->sc_dev, "%s: no mbuf!\n", __func__);
1049 			TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1050 			goto rx_proc_next;
1051 		}
1052 		ds = bf->bf_desc;
1053 		if (ds->ds_link == bf->bf_daddr) {
1054 			/* NB: never process the self-linked entry at the end */
1055 			sc->sc_stats.ast_rx_hitqueueend++;
1056 			break;
1057 		}
1058 		/* XXX sync descriptor memory */
1059 		/*
1060 		 * Must provide the virtual address of the current
1061 		 * descriptor, the physical address, and the virtual
1062 		 * address of the next descriptor in the h/w chain.
1063 		 * This allows the HAL to look ahead to see if the
1064 		 * hardware is done with a descriptor by checking the
1065 		 * done bit in the following descriptor and the address
1066 		 * of the current descriptor the DMA engine is working
1067 		 * on.  All this is necessary because of our use of
1068 		 * a self-linked list to avoid rx overruns.
1069 		 */
1070 		rs = &bf->bf_status.ds_rxstat;
1071 		status = ath_hal_rxprocdesc(ah, ds,
1072 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1073 #ifdef ATH_DEBUG
1074 		if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
1075 			ath_printrxbuf(sc, bf, 0, status == HAL_OK);
1076 #endif
1077 
1078 #ifdef	ATH_DEBUG_ALQ
1079 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS))
1080 		    if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS,
1081 		    sc->sc_rx_statuslen, (char *) ds);
1082 #endif	/* ATH_DEBUG_ALQ */
1083 
1084 		if (status == HAL_EINPROGRESS)
1085 			break;
1086 
1087 		TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1088 		npkts++;
1089 
1090 		/*
1091 		 * Process a single frame.
1092 		 */
1093 		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_POSTREAD);
1094 		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
1095 		bf->bf_m = NULL;
1096 		if (ath_rx_pkt(sc, rs, status, tsf, nf, HAL_RX_QUEUE_HP, bf, m))
1097 			ngood++;
1098 rx_proc_next:
1099 		/*
1100 		 * If there's a holding buffer, insert that onto
1101 		 * the RX list; the hardware is now definitely not pointing
1102 		 * to it now.
1103 		 */
1104 		ret = 0;
1105 		if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf != NULL) {
1106 			TAILQ_INSERT_TAIL(&sc->sc_rxbuf,
1107 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf,
1108 			    bf_list);
1109 			ret = ath_rxbuf_init(sc,
1110 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf);
1111 		}
1112 		/*
1113 		 * Next, throw our buffer into the holding entry.  The hardware
1114 		 * may use the descriptor to read the link pointer before
1115 		 * DMAing the next descriptor in to write out a packet.
1116 		 */
1117 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = bf;
1118 	} while (ret == 0);
1119 
1120 	/* rx signal state monitoring */
1121 	ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
1122 	if (ngood)
1123 		sc->sc_lastrx = tsf;
1124 
1125 	ATH_KTR(sc, ATH_KTR_RXPROC, 2, "ath_rx_proc: npkts=%d, ngood=%d", npkts, ngood);
1126 	/* Queue DFS tasklet if needed */
1127 	if (resched && ath_dfs_tasklet_needed(sc, sc->sc_curchan))
1128 		taskqueue_enqueue(sc->sc_tq, &sc->sc_dfstask);
1129 
1130 	/*
1131 	 * Now that all the RX frames were handled that
1132 	 * need to be handled, kick the PCU if there's
1133 	 * been an RXEOL condition.
1134 	 */
1135 	if (resched && kickpcu) {
1136 		ATH_PCU_LOCK(sc);
1137 		ATH_KTR(sc, ATH_KTR_ERROR, 0, "ath_rx_proc: kickpcu");
1138 		device_printf(sc->sc_dev, "%s: kickpcu; handled %d packets\n",
1139 		    __func__, npkts);
1140 
1141 		/*
1142 		 * Go through the process of fully tearing down
1143 		 * the RX buffers and reinitialising them.
1144 		 *
1145 		 * There's a hardware bug that causes the RX FIFO
1146 		 * to get confused under certain conditions and
1147 		 * constantly write over the same frame, leading
1148 		 * the RX driver code here to get heavily confused.
1149 		 */
1150 		/*
1151 		 * XXX Has RX DMA stopped enough here to just call
1152 		 *     ath_startrecv()?
1153 		 * XXX Do we need to use the holding buffer to restart
1154 		 *     RX DMA by appending entries to the final
1155 		 *     descriptor?  Quite likely.
1156 		 */
1157 #if 1
1158 		ath_startrecv(sc);
1159 #else
1160 		/*
1161 		 * Disabled for now - it'd be nice to be able to do
1162 		 * this in order to limit the amount of CPU time spent
1163 		 * reinitialising the RX side (and thus minimise RX
1164 		 * drops) however there's a hardware issue that
1165 		 * causes things to get too far out of whack.
1166 		 */
1167 		/*
1168 		 * XXX can we hold the PCU lock here?
1169 		 * Are there any net80211 buffer calls involved?
1170 		 */
1171 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1172 		ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1173 		ath_hal_rxena(ah);		/* enable recv descriptors */
1174 		ath_mode_init(sc);		/* set filters, etc. */
1175 		ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
1176 #endif
1177 
1178 		ath_hal_intrset(ah, sc->sc_imask);
1179 		sc->sc_kickpcu = 0;
1180 		ATH_PCU_UNLOCK(sc);
1181 	}
1182 
1183 #ifdef IEEE80211_SUPPORT_SUPERG
1184 	if (resched)
1185 		ieee80211_ff_age_all(ic, 100);
1186 #endif
1187 
1188 	/*
1189 	 * Put the hardware to sleep again if we're done with it.
1190 	 */
1191 	ATH_LOCK(sc);
1192 	ath_power_restore_power_state(sc);
1193 	ATH_UNLOCK(sc);
1194 
1195 	/*
1196 	 * If we hit the maximum number of frames in this round,
1197 	 * reschedule for another immediate pass.  This gives
1198 	 * the TX and TX completion routines time to run, which
1199 	 * will reduce latency.
1200 	 */
1201 	if (npkts >= ATH_RX_MAX)
1202 		sc->sc_rx.recv_sched(sc, resched);
1203 
1204 	ATH_PCU_LOCK(sc);
1205 	sc->sc_rxproc_cnt--;
1206 	ATH_PCU_UNLOCK(sc);
1207 }
1208 #undef	PA2DESC
1209 #undef	ATH_RX_MAX
1210 
1211 /*
1212  * Only run the RX proc if it's not already running.
1213  * Since this may get run as part of the reset/flush path,
1214  * the task can't clash with an existing, running tasklet.
1215  */
1216 static void
1217 ath_legacy_rx_tasklet(void *arg, int npending)
1218 {
1219 	struct ath_softc *sc = arg;
1220 
1221 	ATH_KTR(sc, ATH_KTR_RXPROC, 1, "ath_rx_proc: pending=%d", npending);
1222 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: pending %u\n", __func__, npending);
1223 	ATH_PCU_LOCK(sc);
1224 	if (sc->sc_inreset_cnt > 0) {
1225 		device_printf(sc->sc_dev,
1226 		    "%s: sc_inreset_cnt > 0; skipping\n", __func__);
1227 		ATH_PCU_UNLOCK(sc);
1228 		return;
1229 	}
1230 	ATH_PCU_UNLOCK(sc);
1231 
1232 	ath_rx_proc(sc, 1);
1233 }
1234 
1235 static void
1236 ath_legacy_flushrecv(struct ath_softc *sc)
1237 {
1238 
1239 	ath_rx_proc(sc, 0);
1240 }
1241 
1242 static void
1243 ath_legacy_flush_rxpending(struct ath_softc *sc)
1244 {
1245 
1246 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1247 
1248 	if (sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending != NULL) {
1249 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending);
1250 		sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending = NULL;
1251 	}
1252 	if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending != NULL) {
1253 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending);
1254 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending = NULL;
1255 	}
1256 }
1257 
1258 static int
1259 ath_legacy_flush_rxholdbf(struct ath_softc *sc)
1260 {
1261 	struct ath_buf *bf;
1262 
1263 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1264 	/*
1265 	 * If there are RX holding buffers, free them here and return
1266 	 * them to the list.
1267 	 *
1268 	 * XXX should just verify that bf->bf_m is NULL, as it must
1269 	 * be at this point!
1270 	 */
1271 	bf = sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf;
1272 	if (bf != NULL) {
1273 		if (bf->bf_m != NULL)
1274 			m_freem(bf->bf_m);
1275 		bf->bf_m = NULL;
1276 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1277 		(void) ath_rxbuf_init(sc, bf);
1278 	}
1279 	sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = NULL;
1280 
1281 	bf = sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf;
1282 	if (bf != NULL) {
1283 		if (bf->bf_m != NULL)
1284 			m_freem(bf->bf_m);
1285 		bf->bf_m = NULL;
1286 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1287 		(void) ath_rxbuf_init(sc, bf);
1288 	}
1289 	sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf = NULL;
1290 
1291 	return (0);
1292 }
1293 
1294 /*
1295  * Disable the receive h/w in preparation for a reset.
1296  */
1297 static void
1298 ath_legacy_stoprecv(struct ath_softc *sc, int dodelay)
1299 {
1300 #define	PA2DESC(_sc, _pa) \
1301 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
1302 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
1303 	struct ath_hal *ah = sc->sc_ah;
1304 
1305 	ATH_RX_LOCK(sc);
1306 
1307 	ath_hal_stoppcurecv(ah);	/* disable PCU */
1308 	ath_hal_setrxfilter(ah, 0);	/* clear recv filter */
1309 	ath_hal_stopdmarecv(ah);	/* disable DMA engine */
1310 	/*
1311 	 * TODO: see if this particular DELAY() is required; it may be
1312 	 * masking some missing FIFO flush or DMA sync.
1313 	 */
1314 #if 0
1315 	if (dodelay)
1316 #endif
1317 		DELAY(3000);		/* 3ms is long enough for 1 frame */
1318 #ifdef ATH_DEBUG
1319 	if (sc->sc_debug & (ATH_DEBUG_RESET | ATH_DEBUG_FATAL)) {
1320 		struct ath_buf *bf;
1321 		u_int ix;
1322 
1323 		device_printf(sc->sc_dev,
1324 		    "%s: rx queue %p, link %p\n",
1325 		    __func__,
1326 		    (caddr_t)(uintptr_t) ath_hal_getrxbuf(ah, HAL_RX_QUEUE_HP),
1327 		    sc->sc_rxlink);
1328 		ix = 0;
1329 		TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1330 			struct ath_desc *ds = bf->bf_desc;
1331 			struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
1332 			HAL_STATUS status = ath_hal_rxprocdesc(ah, ds,
1333 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1334 			if (status == HAL_OK || (sc->sc_debug & ATH_DEBUG_FATAL))
1335 				ath_printrxbuf(sc, bf, ix, status == HAL_OK);
1336 			ix++;
1337 		}
1338 	}
1339 #endif
1340 
1341 	(void) ath_legacy_flush_rxpending(sc);
1342 	(void) ath_legacy_flush_rxholdbf(sc);
1343 
1344 	sc->sc_rxlink = NULL;		/* just in case */
1345 
1346 	ATH_RX_UNLOCK(sc);
1347 #undef PA2DESC
1348 }
1349 
1350 /*
1351  * XXX TODO: something was calling startrecv without calling
1352  * stoprecv.  Let's figure out what/why.  It was showing up
1353  * as a mbuf leak (rxpending) and ath_buf leak (holdbf.)
1354  */
1355 
1356 /*
1357  * Enable the receive h/w following a reset.
1358  */
1359 static int
1360 ath_legacy_startrecv(struct ath_softc *sc)
1361 {
1362 	struct ath_hal *ah = sc->sc_ah;
1363 	struct ath_buf *bf;
1364 
1365 	ATH_RX_LOCK(sc);
1366 
1367 	/*
1368 	 * XXX should verify these are already all NULL!
1369 	 */
1370 	sc->sc_rxlink = NULL;
1371 	(void) ath_legacy_flush_rxpending(sc);
1372 	(void) ath_legacy_flush_rxholdbf(sc);
1373 
1374 	/*
1375 	 * Re-chain all of the buffers in the RX buffer list.
1376 	 */
1377 	TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1378 		int error = ath_rxbuf_init(sc, bf);
1379 		if (error != 0) {
1380 			DPRINTF(sc, ATH_DEBUG_RECV,
1381 				"%s: ath_rxbuf_init failed %d\n",
1382 				__func__, error);
1383 			return error;
1384 		}
1385 	}
1386 
1387 	bf = TAILQ_FIRST(&sc->sc_rxbuf);
1388 	ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1389 	ath_hal_rxena(ah);		/* enable recv descriptors */
1390 	ath_mode_init(sc);		/* set filters, etc. */
1391 	ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
1392 
1393 	ATH_RX_UNLOCK(sc);
1394 	return 0;
1395 }
1396 
1397 static int
1398 ath_legacy_dma_rxsetup(struct ath_softc *sc)
1399 {
1400 	int error;
1401 
1402 	error = ath_descdma_setup(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
1403 	    "rx", sizeof(struct ath_desc), ath_rxbuf, 1);
1404 	if (error != 0)
1405 		return (error);
1406 
1407 	return (0);
1408 }
1409 
1410 static int
1411 ath_legacy_dma_rxteardown(struct ath_softc *sc)
1412 {
1413 
1414 	if (sc->sc_rxdma.dd_desc_len != 0)
1415 		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
1416 	return (0);
1417 }
1418 
1419 static void
1420 ath_legacy_recv_sched(struct ath_softc *sc, int dosched)
1421 {
1422 
1423 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1424 }
1425 
1426 static void
1427 ath_legacy_recv_sched_queue(struct ath_softc *sc, HAL_RX_QUEUE q,
1428     int dosched)
1429 {
1430 
1431 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1432 }
1433 
1434 void
1435 ath_recv_setup_legacy(struct ath_softc *sc)
1436 {
1437 
1438 	/* Sensible legacy defaults */
1439 	/*
1440 	 * XXX this should be changed to properly support the
1441 	 * exact RX descriptor size for each HAL.
1442 	 */
1443 	sc->sc_rx_statuslen = sizeof(struct ath_desc);
1444 
1445 	sc->sc_rx.recv_start = ath_legacy_startrecv;
1446 	sc->sc_rx.recv_stop = ath_legacy_stoprecv;
1447 	sc->sc_rx.recv_flush = ath_legacy_flushrecv;
1448 	sc->sc_rx.recv_tasklet = ath_legacy_rx_tasklet;
1449 	sc->sc_rx.recv_rxbuf_init = ath_legacy_rxbuf_init;
1450 
1451 	sc->sc_rx.recv_setup = ath_legacy_dma_rxsetup;
1452 	sc->sc_rx.recv_teardown = ath_legacy_dma_rxteardown;
1453 	sc->sc_rx.recv_sched = ath_legacy_recv_sched;
1454 	sc->sc_rx.recv_sched_queue = ath_legacy_recv_sched_queue;
1455 }
1456