xref: /freebsd/sys/dev/ath/if_ath_rx.c (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer,
12  *    without modification.
13  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14  *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
15  *    redistribution must be conditioned upon including a substantially
16  *    similar Disclaimer requirement for further binary redistribution.
17  *
18  * NO WARRANTY
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
22  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23  * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
24  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
27  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29  * THE POSSIBILITY OF SUCH DAMAGES.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 /*
36  * Driver for the Atheros Wireless LAN controller.
37  *
38  * This software is derived from work of Atsushi Onoe; his contribution
39  * is greatly appreciated.
40  */
41 
42 #include "opt_inet.h"
43 #include "opt_ath.h"
44 /*
45  * This is needed for register operations which are performed
46  * by the driver - eg, calls to ath_hal_gettsf32().
47  *
48  * It's also required for any AH_DEBUG checks in here, eg the
49  * module dependencies.
50  */
51 #include "opt_ah.h"
52 #include "opt_wlan.h"
53 
54 #include <sys/param.h>
55 #include <sys/systm.h>
56 #include <sys/sysctl.h>
57 #include <sys/mbuf.h>
58 #include <sys/malloc.h>
59 #include <sys/lock.h>
60 #include <sys/mutex.h>
61 #include <sys/kernel.h>
62 #include <sys/socket.h>
63 #include <sys/sockio.h>
64 #include <sys/errno.h>
65 #include <sys/callout.h>
66 #include <sys/bus.h>
67 #include <sys/endian.h>
68 #include <sys/kthread.h>
69 #include <sys/taskqueue.h>
70 #include <sys/priv.h>
71 #include <sys/module.h>
72 #include <sys/ktr.h>
73 #include <sys/smp.h>	/* for mp_ncpus */
74 
75 #include <machine/bus.h>
76 
77 #include <net/if.h>
78 #include <net/if_var.h>
79 #include <net/if_dl.h>
80 #include <net/if_media.h>
81 #include <net/if_types.h>
82 #include <net/if_arp.h>
83 #include <net/ethernet.h>
84 #include <net/if_llc.h>
85 
86 #include <net80211/ieee80211_var.h>
87 #include <net80211/ieee80211_regdomain.h>
88 #ifdef IEEE80211_SUPPORT_SUPERG
89 #include <net80211/ieee80211_superg.h>
90 #endif
91 #ifdef IEEE80211_SUPPORT_TDMA
92 #include <net80211/ieee80211_tdma.h>
93 #endif
94 
95 #include <net/bpf.h>
96 
97 #ifdef INET
98 #include <netinet/in.h>
99 #include <netinet/if_ether.h>
100 #endif
101 
102 #include <dev/ath/if_athvar.h>
103 #include <dev/ath/ath_hal/ah_devid.h>		/* XXX for softled */
104 #include <dev/ath/ath_hal/ah_diagcodes.h>
105 
106 #include <dev/ath/if_ath_debug.h>
107 #include <dev/ath/if_ath_misc.h>
108 #include <dev/ath/if_ath_tsf.h>
109 #include <dev/ath/if_ath_tx.h>
110 #include <dev/ath/if_ath_sysctl.h>
111 #include <dev/ath/if_ath_led.h>
112 #include <dev/ath/if_ath_keycache.h>
113 #include <dev/ath/if_ath_rx.h>
114 #include <dev/ath/if_ath_beacon.h>
115 #include <dev/ath/if_athdfs.h>
116 #include <dev/ath/if_ath_descdma.h>
117 
118 #ifdef ATH_TX99_DIAG
119 #include <dev/ath/ath_tx99/ath_tx99.h>
120 #endif
121 
122 #ifdef	ATH_DEBUG_ALQ
123 #include <dev/ath/if_ath_alq.h>
124 #endif
125 
126 #include <dev/ath/if_ath_lna_div.h>
127 
128 /*
129  * Calculate the receive filter according to the
130  * operating mode and state:
131  *
132  * o always accept unicast, broadcast, and multicast traffic
133  * o accept PHY error frames when hardware doesn't have MIB support
134  *   to count and we need them for ANI (sta mode only until recently)
135  *   and we are not scanning (ANI is disabled)
136  *   NB: older hal's add rx filter bits out of sight and we need to
137  *	 blindly preserve them
138  * o probe request frames are accepted only when operating in
139  *   hostap, adhoc, mesh, or monitor modes
140  * o enable promiscuous mode
141  *   - when in monitor mode
142  *   - if interface marked PROMISC (assumes bridge setting is filtered)
143  * o accept beacons:
144  *   - when operating in station mode for collecting rssi data when
145  *     the station is otherwise quiet, or
146  *   - when operating in adhoc mode so the 802.11 layer creates
147  *     node table entries for peers,
148  *   - when scanning
149  *   - when doing s/w beacon miss (e.g. for ap+sta)
150  *   - when operating in ap mode in 11g to detect overlapping bss that
151  *     require protection
152  *   - when operating in mesh mode to detect neighbors
153  * o accept control frames:
154  *   - when in monitor mode
155  * XXX HT protection for 11n
156  */
157 u_int32_t
158 ath_calcrxfilter(struct ath_softc *sc)
159 {
160 	struct ieee80211com *ic = &sc->sc_ic;
161 	u_int32_t rfilt;
162 
163 	rfilt = HAL_RX_FILTER_UCAST | HAL_RX_FILTER_BCAST | HAL_RX_FILTER_MCAST;
164 	if (!sc->sc_needmib && !sc->sc_scanning)
165 		rfilt |= HAL_RX_FILTER_PHYERR;
166 	if (ic->ic_opmode != IEEE80211_M_STA)
167 		rfilt |= HAL_RX_FILTER_PROBEREQ;
168 	/* XXX ic->ic_monvaps != 0? */
169 	if (ic->ic_opmode == IEEE80211_M_MONITOR || ic->ic_promisc > 0)
170 		rfilt |= HAL_RX_FILTER_PROM;
171 
172 	/*
173 	 * Only listen to all beacons if we're scanning.
174 	 *
175 	 * Otherwise we only really need to hear beacons from
176 	 * our own BSSID.
177 	 *
178 	 * IBSS? software beacon miss? Just receive all beacons.
179 	 * We need to hear beacons/probe requests from everyone so
180 	 * we can merge ibss.
181 	 */
182 	if (ic->ic_opmode == IEEE80211_M_IBSS || sc->sc_swbmiss) {
183 		rfilt |= HAL_RX_FILTER_BEACON;
184 	} else if (ic->ic_opmode == IEEE80211_M_STA) {
185 		if (sc->sc_do_mybeacon && ! sc->sc_scanning) {
186 			rfilt |= HAL_RX_FILTER_MYBEACON;
187 		} else { /* scanning, non-mybeacon chips */
188 			rfilt |= HAL_RX_FILTER_BEACON;
189 		}
190 	}
191 
192 	/*
193 	 * NB: We don't recalculate the rx filter when
194 	 * ic_protmode changes; otherwise we could do
195 	 * this only when ic_protmode != NONE.
196 	 */
197 	if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
198 	    IEEE80211_IS_CHAN_ANYG(ic->ic_curchan))
199 		rfilt |= HAL_RX_FILTER_BEACON;
200 
201 	/*
202 	 * Enable hardware PS-POLL RX only for hostap mode;
203 	 * STA mode sends PS-POLL frames but never
204 	 * receives them.
205 	 */
206 	if (ath_hal_getcapability(sc->sc_ah, HAL_CAP_PSPOLL,
207 	    0, NULL) == HAL_OK &&
208 	    ic->ic_opmode == IEEE80211_M_HOSTAP)
209 		rfilt |= HAL_RX_FILTER_PSPOLL;
210 
211 	if (sc->sc_nmeshvaps) {
212 		rfilt |= HAL_RX_FILTER_BEACON;
213 		if (sc->sc_hasbmatch)
214 			rfilt |= HAL_RX_FILTER_BSSID;
215 		else
216 			rfilt |= HAL_RX_FILTER_PROM;
217 	}
218 	if (ic->ic_opmode == IEEE80211_M_MONITOR)
219 		rfilt |= HAL_RX_FILTER_CONTROL;
220 
221 	/*
222 	 * Enable RX of compressed BAR frames only when doing
223 	 * 802.11n. Required for A-MPDU.
224 	 */
225 	if (IEEE80211_IS_CHAN_HT(ic->ic_curchan))
226 		rfilt |= HAL_RX_FILTER_COMPBAR;
227 
228 	/*
229 	 * Enable radar PHY errors if requested by the
230 	 * DFS module.
231 	 */
232 	if (sc->sc_dodfs)
233 		rfilt |= HAL_RX_FILTER_PHYRADAR;
234 
235 	/*
236 	 * Enable spectral PHY errors if requested by the
237 	 * spectral module.
238 	 */
239 	if (sc->sc_dospectral)
240 		rfilt |= HAL_RX_FILTER_PHYRADAR;
241 
242 	DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x, %s\n",
243 	    __func__, rfilt, ieee80211_opmode_name[ic->ic_opmode]);
244 	return rfilt;
245 }
246 
247 static int
248 ath_legacy_rxbuf_init(struct ath_softc *sc, struct ath_buf *bf)
249 {
250 	struct ath_hal *ah = sc->sc_ah;
251 	int error;
252 	struct mbuf *m;
253 	struct ath_desc *ds;
254 
255 	/* XXX TODO: ATH_RX_LOCK_ASSERT(sc); */
256 
257 	m = bf->bf_m;
258 	if (m == NULL) {
259 		/*
260 		 * NB: by assigning a page to the rx dma buffer we
261 		 * implicitly satisfy the Atheros requirement that
262 		 * this buffer be cache-line-aligned and sized to be
263 		 * multiple of the cache line size.  Not doing this
264 		 * causes weird stuff to happen (for the 5210 at least).
265 		 */
266 		m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
267 		if (m == NULL) {
268 			DPRINTF(sc, ATH_DEBUG_ANY,
269 				"%s: no mbuf/cluster\n", __func__);
270 			sc->sc_stats.ast_rx_nombuf++;
271 			return ENOMEM;
272 		}
273 		m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;
274 
275 		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat,
276 					     bf->bf_dmamap, m,
277 					     bf->bf_segs, &bf->bf_nseg,
278 					     BUS_DMA_NOWAIT);
279 		if (error != 0) {
280 			DPRINTF(sc, ATH_DEBUG_ANY,
281 			    "%s: bus_dmamap_load_mbuf_sg failed; error %d\n",
282 			    __func__, error);
283 			sc->sc_stats.ast_rx_busdma++;
284 			m_freem(m);
285 			return error;
286 		}
287 		KASSERT(bf->bf_nseg == 1,
288 			("multi-segment packet; nseg %u", bf->bf_nseg));
289 		bf->bf_m = m;
290 	}
291 	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREREAD);
292 
293 	/*
294 	 * Setup descriptors.  For receive we always terminate
295 	 * the descriptor list with a self-linked entry so we'll
296 	 * not get overrun under high load (as can happen with a
297 	 * 5212 when ANI processing enables PHY error frames).
298 	 *
299 	 * To insure the last descriptor is self-linked we create
300 	 * each descriptor as self-linked and add it to the end.  As
301 	 * each additional descriptor is added the previous self-linked
302 	 * entry is ``fixed'' naturally.  This should be safe even
303 	 * if DMA is happening.  When processing RX interrupts we
304 	 * never remove/process the last, self-linked, entry on the
305 	 * descriptor list.  This insures the hardware always has
306 	 * someplace to write a new frame.
307 	 */
308 	/*
309 	 * 11N: we can no longer afford to self link the last descriptor.
310 	 * MAC acknowledges BA status as long as it copies frames to host
311 	 * buffer (or rx fifo). This can incorrectly acknowledge packets
312 	 * to a sender if last desc is self-linked.
313 	 */
314 	ds = bf->bf_desc;
315 	if (sc->sc_rxslink)
316 		ds->ds_link = bf->bf_daddr;	/* link to self */
317 	else
318 		ds->ds_link = 0;		/* terminate the list */
319 	ds->ds_data = bf->bf_segs[0].ds_addr;
320 	ath_hal_setuprxdesc(ah, ds
321 		, m->m_len		/* buffer size */
322 		, 0
323 	);
324 
325 	if (sc->sc_rxlink != NULL)
326 		*sc->sc_rxlink = bf->bf_daddr;
327 	sc->sc_rxlink = &ds->ds_link;
328 	return 0;
329 }
330 
331 /*
332  * Intercept management frames to collect beacon rssi data
333  * and to do ibss merges.
334  */
335 void
336 ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
337 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
338 {
339 	struct ieee80211vap *vap = ni->ni_vap;
340 	struct ath_softc *sc = vap->iv_ic->ic_softc;
341 	uint64_t tsf_beacon_old, tsf_beacon;
342 	uint64_t nexttbtt;
343 	int64_t tsf_delta;
344 	int32_t tsf_delta_bmiss;
345 	int32_t tsf_remainder;
346 	uint64_t tsf_beacon_target;
347 	int tsf_intval;
348 
349 	tsf_beacon_old = ((uint64_t) le32dec(ni->ni_tstamp.data + 4)) << 32;
350 	tsf_beacon_old |= le32dec(ni->ni_tstamp.data);
351 
352 #define	TU_TO_TSF(_tu)	(((u_int64_t)(_tu)) << 10)
353 	tsf_intval = 1;
354 	if (ni->ni_intval > 0) {
355 		tsf_intval = TU_TO_TSF(ni->ni_intval);
356 	}
357 #undef	TU_TO_TSF
358 
359 	/*
360 	 * Call up first so subsequent work can use information
361 	 * potentially stored in the node (e.g. for ibss merge).
362 	 */
363 	ATH_VAP(vap)->av_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
364 	switch (subtype) {
365 	case IEEE80211_FC0_SUBTYPE_BEACON:
366 		/*
367 		 * Always update the per-node beacon RSSI if we're hearing
368 		 * beacons from that node.
369 		 */
370 		ATH_RSSI_LPF(ATH_NODE(ni)->an_node_stats.ns_avgbrssi, rssi);
371 
372 		/*
373 		 * Only do the following processing if it's for
374 		 * the current BSS.
375 		 *
376 		 * In scan and IBSS mode we receive all beacons,
377 		 * which means we need to filter out stuff
378 		 * that isn't for us or we'll end up constantly
379 		 * trying to sync / merge to BSSes that aren't
380 		 * actually us.
381 		 */
382 		if ((vap->iv_opmode != IEEE80211_M_HOSTAP) &&
383 		    IEEE80211_ADDR_EQ(ni->ni_bssid, vap->iv_bss->ni_bssid)) {
384 			/* update rssi statistics for use by the hal */
385 			/* XXX unlocked check against vap->iv_bss? */
386 			ATH_RSSI_LPF(sc->sc_halstats.ns_avgbrssi, rssi);
387 
388 			tsf_beacon = ((uint64_t) le32dec(ni->ni_tstamp.data + 4)) << 32;
389 			tsf_beacon |= le32dec(ni->ni_tstamp.data);
390 
391 			nexttbtt = ath_hal_getnexttbtt(sc->sc_ah);
392 
393 			/*
394 			 * Let's calculate the delta and remainder, so we can see
395 			 * if the beacon timer from the AP is varying by more than
396 			 * a few TU.  (Which would be a huge, huge problem.)
397 			 */
398 			tsf_delta = (long long) tsf_beacon - (long long) tsf_beacon_old;
399 
400 			tsf_delta_bmiss = tsf_delta / tsf_intval;
401 
402 			/*
403 			 * If our delta is greater than half the beacon interval,
404 			 * let's round the bmiss value up to the next beacon
405 			 * interval.  Ie, we're running really, really early
406 			 * on the next beacon.
407 			 */
408 			if (tsf_delta % tsf_intval > (tsf_intval / 2))
409 				tsf_delta_bmiss ++;
410 
411 			tsf_beacon_target = tsf_beacon_old +
412 			    (((unsigned long long) tsf_delta_bmiss) * (long long) tsf_intval);
413 
414 			/*
415 			 * The remainder using '%' is between 0 .. intval-1.
416 			 * If we're actually running too fast, then the remainder
417 			 * will be some large number just under intval-1.
418 			 * So we need to look at whether we're running
419 			 * before or after the target beacon interval
420 			 * and if we are, modify how we do the remainder
421 			 * calculation.
422 			 */
423 			if (tsf_beacon < tsf_beacon_target) {
424 				tsf_remainder =
425 				    -(tsf_intval - ((tsf_beacon - tsf_beacon_old) % tsf_intval));
426 			} else {
427 				tsf_remainder = (tsf_beacon - tsf_beacon_old) % tsf_intval;
428 			}
429 
430 			DPRINTF(sc, ATH_DEBUG_BEACON, "%s: %s: old_tsf=%llu (%u), new_tsf=%llu (%u), target_tsf=%llu (%u), delta=%lld, bmiss=%d, remainder=%d\n",
431 			    __func__,
432 			    ieee80211_get_vap_ifname(vap),
433 			    (unsigned long long) tsf_beacon_old,
434 			    (unsigned int) (tsf_beacon_old >> 10),
435 			    (unsigned long long) tsf_beacon,
436 			    (unsigned int ) (tsf_beacon >> 10),
437 			    (unsigned long long) tsf_beacon_target,
438 			    (unsigned int) (tsf_beacon_target >> 10),
439 			    (long long) tsf_delta,
440 			    tsf_delta_bmiss,
441 			    tsf_remainder);
442 
443 			DPRINTF(sc, ATH_DEBUG_BEACON, "%s: %s: ni=%6D bssid=%6D tsf=%llu (%u), nexttbtt=%llu (%u), delta=%d\n",
444 			    __func__,
445 			    ieee80211_get_vap_ifname(vap),
446 			    ni->ni_bssid, ":",
447 			    vap->iv_bss->ni_bssid, ":",
448 			    (unsigned long long) tsf_beacon,
449 			    (unsigned int) (tsf_beacon >> 10),
450 			    (unsigned long long) nexttbtt,
451 			    (unsigned int) (nexttbtt >> 10),
452 			    (int32_t) tsf_beacon - (int32_t) nexttbtt + tsf_intval);
453 
454 			/*
455 			 * We only do syncbeacon on STA VAPs; not on IBSS;
456 			 * but don't do it with swbmiss enabled or we
457 			 * may end up overwriting AP mode beacon config.
458 			 *
459 			 * The driver (and net80211) should be smarter about
460 			 * this..
461 			 */
462 			if (vap->iv_opmode == IEEE80211_M_STA &&
463 			    sc->sc_syncbeacon &&
464 			    (!sc->sc_swbmiss) &&
465 			    ni == vap->iv_bss &&
466 			    (vap->iv_state == IEEE80211_S_RUN || vap->iv_state == IEEE80211_S_SLEEP)) {
467 				DPRINTF(sc, ATH_DEBUG_BEACON,
468 				    "%s: syncbeacon=1; syncing\n",
469 				    __func__);
470 				/*
471 				 * Resync beacon timers using the tsf of the beacon
472 				 * frame we just received.
473 				 */
474 				ath_beacon_config(sc, vap);
475 				sc->sc_syncbeacon = 0;
476 			}
477 		}
478 
479 		/* fall thru... */
480 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
481 		if (vap->iv_opmode == IEEE80211_M_IBSS &&
482 		    vap->iv_state == IEEE80211_S_RUN &&
483 		    ieee80211_ibss_merge_check(ni)) {
484 			uint32_t rstamp = sc->sc_lastrs->rs_tstamp;
485 			uint64_t tsf = ath_extend_tsf(sc, rstamp,
486 				ath_hal_gettsf64(sc->sc_ah));
487 			/*
488 			 * Handle ibss merge as needed; check the tsf on the
489 			 * frame before attempting the merge.  The 802.11 spec
490 			 * says the station should change it's bssid to match
491 			 * the oldest station with the same ssid, where oldest
492 			 * is determined by the tsf.  Note that hardware
493 			 * reconfiguration happens through callback to
494 			 * ath_newstate as the state machine will go from
495 			 * RUN -> RUN when this happens.
496 			 */
497 			if (le64toh(ni->ni_tstamp.tsf) >= tsf) {
498 				DPRINTF(sc, ATH_DEBUG_STATE,
499 				    "ibss merge, rstamp %u tsf %ju "
500 				    "tstamp %ju\n", rstamp, (uintmax_t)tsf,
501 				    (uintmax_t)ni->ni_tstamp.tsf);
502 				(void) ieee80211_ibss_merge(ni);
503 			}
504 		}
505 		break;
506 	}
507 }
508 
509 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
510 static void
511 ath_rx_tap_vendor(struct ath_softc *sc, struct mbuf *m,
512     const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
513 {
514 
515 	/* Fill in the extension bitmap */
516 	sc->sc_rx_th.wr_ext_bitmap = htole32(1 << ATH_RADIOTAP_VENDOR_HEADER);
517 
518 	/* Fill in the vendor header */
519 	sc->sc_rx_th.wr_vh.vh_oui[0] = 0x7f;
520 	sc->sc_rx_th.wr_vh.vh_oui[1] = 0x03;
521 	sc->sc_rx_th.wr_vh.vh_oui[2] = 0x00;
522 
523 	/* XXX what should this be? */
524 	sc->sc_rx_th.wr_vh.vh_sub_ns = 0;
525 	sc->sc_rx_th.wr_vh.vh_skip_len =
526 	    htole16(sizeof(struct ath_radiotap_vendor_hdr));
527 
528 	/* General version info */
529 	sc->sc_rx_th.wr_v.vh_version = 1;
530 
531 	sc->sc_rx_th.wr_v.vh_rx_chainmask = sc->sc_rxchainmask;
532 
533 	/* rssi */
534 	sc->sc_rx_th.wr_v.rssi_ctl[0] = rs->rs_rssi_ctl[0];
535 	sc->sc_rx_th.wr_v.rssi_ctl[1] = rs->rs_rssi_ctl[1];
536 	sc->sc_rx_th.wr_v.rssi_ctl[2] = rs->rs_rssi_ctl[2];
537 	sc->sc_rx_th.wr_v.rssi_ext[0] = rs->rs_rssi_ext[0];
538 	sc->sc_rx_th.wr_v.rssi_ext[1] = rs->rs_rssi_ext[1];
539 	sc->sc_rx_th.wr_v.rssi_ext[2] = rs->rs_rssi_ext[2];
540 
541 	/* evm */
542 	sc->sc_rx_th.wr_v.evm[0] = rs->rs_evm0;
543 	sc->sc_rx_th.wr_v.evm[1] = rs->rs_evm1;
544 	sc->sc_rx_th.wr_v.evm[2] = rs->rs_evm2;
545 	/* These are only populated from the AR9300 or later */
546 	sc->sc_rx_th.wr_v.evm[3] = rs->rs_evm3;
547 	sc->sc_rx_th.wr_v.evm[4] = rs->rs_evm4;
548 
549 	/* direction */
550 	sc->sc_rx_th.wr_v.vh_flags = ATH_VENDOR_PKT_RX;
551 
552 	/* RX rate */
553 	sc->sc_rx_th.wr_v.vh_rx_hwrate = rs->rs_rate;
554 
555 	/* RX flags */
556 	sc->sc_rx_th.wr_v.vh_rs_flags = rs->rs_flags;
557 
558 	if (rs->rs_isaggr)
559 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_ISAGGR;
560 	if (rs->rs_moreaggr)
561 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_MOREAGGR;
562 
563 	/* phyerr info */
564 	if (rs->rs_status & HAL_RXERR_PHY) {
565 		sc->sc_rx_th.wr_v.vh_phyerr_code = rs->rs_phyerr;
566 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_RXPHYERR;
567 	} else {
568 		sc->sc_rx_th.wr_v.vh_phyerr_code = 0xff;
569 	}
570 	sc->sc_rx_th.wr_v.vh_rs_status = rs->rs_status;
571 	sc->sc_rx_th.wr_v.vh_rssi = rs->rs_rssi;
572 }
573 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
574 
575 static void
576 ath_rx_tap(struct ath_softc *sc, struct mbuf *m,
577 	const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
578 {
579 #define	CHAN_HT20	htole32(IEEE80211_CHAN_HT20)
580 #define	CHAN_HT40U	htole32(IEEE80211_CHAN_HT40U)
581 #define	CHAN_HT40D	htole32(IEEE80211_CHAN_HT40D)
582 #define	CHAN_HT		(CHAN_HT20|CHAN_HT40U|CHAN_HT40D)
583 	const HAL_RATE_TABLE *rt;
584 	uint8_t rix;
585 
586 	rt = sc->sc_currates;
587 	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
588 	rix = rt->rateCodeToIndex[rs->rs_rate];
589 	sc->sc_rx_th.wr_rate = sc->sc_hwmap[rix].ieeerate;
590 	sc->sc_rx_th.wr_flags = sc->sc_hwmap[rix].rxflags;
591 
592 	/* 802.11 specific flags */
593 	sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT;
594 	if (rs->rs_status & HAL_RXERR_PHY) {
595 		/*
596 		 * PHY error - make sure the channel flags
597 		 * reflect the actual channel configuration,
598 		 * not the received frame.
599 		 */
600 		if (IEEE80211_IS_CHAN_HT40U(sc->sc_curchan))
601 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
602 		else if (IEEE80211_IS_CHAN_HT40D(sc->sc_curchan))
603 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
604 		else if (IEEE80211_IS_CHAN_HT20(sc->sc_curchan))
605 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
606 	} else if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) {	/* HT rate */
607 		struct ieee80211com *ic = &sc->sc_ic;
608 
609 		if ((rs->rs_flags & HAL_RX_2040) == 0)
610 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
611 		else if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan))
612 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
613 		else
614 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
615 
616 		if (rs->rs_flags & HAL_RX_GI)
617 			sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_SHORTGI;
618 	}
619 
620 	sc->sc_rx_th.wr_tsf = htole64(ath_extend_tsf(sc, rs->rs_tstamp, tsf));
621 	if (rs->rs_status & HAL_RXERR_CRC)
622 		sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_BADFCS;
623 	/* XXX propagate other error flags from descriptor */
624 	sc->sc_rx_th.wr_antnoise = nf;
625 	sc->sc_rx_th.wr_antsignal = nf + rs->rs_rssi;
626 	sc->sc_rx_th.wr_antenna = rs->rs_antenna;
627 #undef CHAN_HT
628 #undef CHAN_HT20
629 #undef CHAN_HT40U
630 #undef CHAN_HT40D
631 }
632 
633 static void
634 ath_handle_micerror(struct ieee80211com *ic,
635 	struct ieee80211_frame *wh, int keyix)
636 {
637 	struct ieee80211_node *ni;
638 
639 	/* XXX recheck MIC to deal w/ chips that lie */
640 	/* XXX discard MIC errors on !data frames */
641 	ni = ieee80211_find_rxnode(ic, (const struct ieee80211_frame_min *) wh);
642 	if (ni != NULL) {
643 		ieee80211_notify_michael_failure(ni->ni_vap, wh, keyix);
644 		ieee80211_free_node(ni);
645 	}
646 }
647 
648 /*
649  * Process a single packet.
650  *
651  * The mbuf must already be synced, unmapped and removed from bf->bf_m
652  * by this stage.
653  *
654  * The mbuf must be consumed by this routine - either passed up the
655  * net80211 stack, put on the holding queue, or freed.
656  */
657 int
658 ath_rx_pkt(struct ath_softc *sc, struct ath_rx_status *rs, HAL_STATUS status,
659     uint64_t tsf, int nf, HAL_RX_QUEUE qtype, struct ath_buf *bf,
660     struct mbuf *m)
661 {
662 	uint64_t rstamp;
663 	/* XXX TODO: make this an mbuf tag? */
664 	struct ieee80211_rx_stats rxs;
665 	int len, type, i;
666 	struct ieee80211com *ic = &sc->sc_ic;
667 	struct ieee80211_node *ni;
668 	int is_good = 0;
669 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
670 
671 	NET_EPOCH_ASSERT();
672 
673 	/*
674 	 * Calculate the correct 64 bit TSF given
675 	 * the TSF64 register value and rs_tstamp.
676 	 */
677 	rstamp = ath_extend_tsf(sc, rs->rs_tstamp, tsf);
678 
679 	/* 802.11 return codes - These aren't specifically errors */
680 	if (rs->rs_flags & HAL_RX_GI)
681 		sc->sc_stats.ast_rx_halfgi++;
682 	if (rs->rs_flags & HAL_RX_2040)
683 		sc->sc_stats.ast_rx_2040++;
684 	if (rs->rs_flags & HAL_RX_DELIM_CRC_PRE)
685 		sc->sc_stats.ast_rx_pre_crc_err++;
686 	if (rs->rs_flags & HAL_RX_DELIM_CRC_POST)
687 		sc->sc_stats.ast_rx_post_crc_err++;
688 	if (rs->rs_flags & HAL_RX_DECRYPT_BUSY)
689 		sc->sc_stats.ast_rx_decrypt_busy_err++;
690 	if (rs->rs_flags & HAL_RX_HI_RX_CHAIN)
691 		sc->sc_stats.ast_rx_hi_rx_chain++;
692 	if (rs->rs_flags & HAL_RX_STBC)
693 		sc->sc_stats.ast_rx_stbc++;
694 
695 	if (rs->rs_status != 0) {
696 		if (rs->rs_status & HAL_RXERR_CRC)
697 			sc->sc_stats.ast_rx_crcerr++;
698 		if (rs->rs_status & HAL_RXERR_FIFO)
699 			sc->sc_stats.ast_rx_fifoerr++;
700 		if (rs->rs_status & HAL_RXERR_PHY) {
701 			sc->sc_stats.ast_rx_phyerr++;
702 			/* Process DFS radar events */
703 			if ((rs->rs_phyerr == HAL_PHYERR_RADAR) ||
704 			    (rs->rs_phyerr == HAL_PHYERR_FALSE_RADAR_EXT)) {
705 				/* Now pass it to the radar processing code */
706 				ath_dfs_process_phy_err(sc, m, rstamp, rs);
707 			}
708 
709 			/*
710 			 * Be suitably paranoid about receiving phy errors
711 			 * out of the stats array bounds
712 			 */
713 			if (rs->rs_phyerr < ATH_IOCTL_STATS_NUM_RX_PHYERR)
714 				sc->sc_stats.ast_rx_phy[rs->rs_phyerr]++;
715 			goto rx_error;	/* NB: don't count in ierrors */
716 		}
717 		if (rs->rs_status & HAL_RXERR_DECRYPT) {
718 			/*
719 			 * Decrypt error.  If the error occurred
720 			 * because there was no hardware key, then
721 			 * let the frame through so the upper layers
722 			 * can process it.  This is necessary for 5210
723 			 * parts which have no way to setup a ``clear''
724 			 * key cache entry.
725 			 *
726 			 * XXX do key cache faulting
727 			 */
728 			if (rs->rs_keyix == HAL_RXKEYIX_INVALID)
729 				goto rx_accept;
730 			sc->sc_stats.ast_rx_badcrypt++;
731 		}
732 		/*
733 		 * Similar as above - if the failure was a keymiss
734 		 * just punt it up to the upper layers for now.
735 		 */
736 		if (rs->rs_status & HAL_RXERR_KEYMISS) {
737 			sc->sc_stats.ast_rx_keymiss++;
738 			goto rx_accept;
739 		}
740 		if (rs->rs_status & HAL_RXERR_MIC) {
741 			sc->sc_stats.ast_rx_badmic++;
742 			/*
743 			 * Do minimal work required to hand off
744 			 * the 802.11 header for notification.
745 			 */
746 			/* XXX frag's and qos frames */
747 			len = rs->rs_datalen;
748 			if (len >= sizeof (struct ieee80211_frame)) {
749 				ath_handle_micerror(ic,
750 				    mtod(m, struct ieee80211_frame *),
751 				    sc->sc_splitmic ?
752 					rs->rs_keyix-32 : rs->rs_keyix);
753 			}
754 		}
755 		counter_u64_add(ic->ic_ierrors, 1);
756 rx_error:
757 		/*
758 		 * Cleanup any pending partial frame.
759 		 */
760 		if (re->m_rxpending != NULL) {
761 			m_freem(re->m_rxpending);
762 			re->m_rxpending = NULL;
763 		}
764 		/*
765 		 * When a tap is present pass error frames
766 		 * that have been requested.  By default we
767 		 * pass decrypt+mic errors but others may be
768 		 * interesting (e.g. crc).
769 		 */
770 		if (ieee80211_radiotap_active(ic) &&
771 		    (rs->rs_status & sc->sc_monpass)) {
772 			/* NB: bpf needs the mbuf length setup */
773 			len = rs->rs_datalen;
774 			m->m_pkthdr.len = m->m_len = len;
775 			ath_rx_tap(sc, m, rs, rstamp, nf);
776 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
777 			ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
778 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
779 			ieee80211_radiotap_rx_all(ic, m);
780 		}
781 		/* XXX pass MIC errors up for s/w reclaculation */
782 		m_freem(m); m = NULL;
783 		goto rx_next;
784 	}
785 rx_accept:
786 	len = rs->rs_datalen;
787 	m->m_len = len;
788 
789 	if (rs->rs_more) {
790 		/*
791 		 * Frame spans multiple descriptors; save
792 		 * it for the next completed descriptor, it
793 		 * will be used to construct a jumbogram.
794 		 */
795 		if (re->m_rxpending != NULL) {
796 			/* NB: max frame size is currently 2 clusters */
797 			sc->sc_stats.ast_rx_toobig++;
798 			m_freem(re->m_rxpending);
799 		}
800 		m->m_pkthdr.len = len;
801 		re->m_rxpending = m;
802 		m = NULL;
803 		goto rx_next;
804 	} else if (re->m_rxpending != NULL) {
805 		/*
806 		 * This is the second part of a jumbogram,
807 		 * chain it to the first mbuf, adjust the
808 		 * frame length, and clear the rxpending state.
809 		 */
810 		re->m_rxpending->m_next = m;
811 		re->m_rxpending->m_pkthdr.len += len;
812 		m = re->m_rxpending;
813 		re->m_rxpending = NULL;
814 	} else {
815 		/*
816 		 * Normal single-descriptor receive; setup packet length.
817 		 */
818 		m->m_pkthdr.len = len;
819 	}
820 
821 	/*
822 	 * Validate rs->rs_antenna.
823 	 *
824 	 * Some users w/ AR9285 NICs have reported crashes
825 	 * here because rs_antenna field is bogusly large.
826 	 * Let's enforce the maximum antenna limit of 8
827 	 * (and it shouldn't be hard coded, but that's a
828 	 * separate problem) and if there's an issue, print
829 	 * out an error and adjust rs_antenna to something
830 	 * sensible.
831 	 *
832 	 * This code should be removed once the actual
833 	 * root cause of the issue has been identified.
834 	 * For example, it may be that the rs_antenna
835 	 * field is only valid for the last frame of
836 	 * an aggregate and it just happens that it is
837 	 * "mostly" right. (This is a general statement -
838 	 * the majority of the statistics are only valid
839 	 * for the last frame in an aggregate.
840 	 */
841 	if (rs->rs_antenna >= ATH_IOCTL_STATS_NUM_RX_ANTENNA) {
842 		device_printf(sc->sc_dev, "%s: rs_antenna > 7 (%d)\n",
843 		    __func__, rs->rs_antenna);
844 #ifdef	ATH_DEBUG
845 		ath_printrxbuf(sc, bf, 0, status == HAL_OK);
846 #endif /* ATH_DEBUG */
847 		rs->rs_antenna = 0;	/* XXX better than nothing */
848 	}
849 
850 	/*
851 	 * If this is an AR9285/AR9485, then the receive and LNA
852 	 * configuration is stored in RSSI[2] / EXTRSSI[2].
853 	 * We can extract this out to build a much better
854 	 * receive antenna profile.
855 	 *
856 	 * Yes, this just blurts over the above RX antenna field
857 	 * for now.  It's fine, the AR9285 doesn't really use
858 	 * that.
859 	 *
860 	 * Later on we should store away the fine grained LNA
861 	 * information and keep separate counters just for
862 	 * that.  It'll help when debugging the AR9285/AR9485
863 	 * combined diversity code.
864 	 */
865 	if (sc->sc_rx_lnamixer) {
866 		rs->rs_antenna = 0;
867 
868 		/* Bits 0:1 - the LNA configuration used */
869 		rs->rs_antenna |=
870 		    ((rs->rs_rssi_ctl[2] & HAL_RX_LNA_CFG_USED)
871 		      >> HAL_RX_LNA_CFG_USED_S);
872 
873 		/* Bit 2 - the external RX antenna switch */
874 		if (rs->rs_rssi_ctl[2] & HAL_RX_LNA_EXTCFG)
875 			rs->rs_antenna |= 0x4;
876 	}
877 
878 	sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;
879 
880 	/*
881 	 * Populate the rx status block.  When there are bpf
882 	 * listeners we do the additional work to provide
883 	 * complete status.  Otherwise we fill in only the
884 	 * material required by ieee80211_input.  Note that
885 	 * noise setting is filled in above.
886 	 */
887 	if (ieee80211_radiotap_active(ic)) {
888 		ath_rx_tap(sc, m, rs, rstamp, nf);
889 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
890 		ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
891 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
892 	}
893 
894 	/*
895 	 * From this point on we assume the frame is at least
896 	 * as large as ieee80211_frame_min; verify that.
897 	 */
898 	if (len < IEEE80211_MIN_LEN) {
899 		if (!ieee80211_radiotap_active(ic)) {
900 			DPRINTF(sc, ATH_DEBUG_RECV,
901 			    "%s: short packet %d\n", __func__, len);
902 			sc->sc_stats.ast_rx_tooshort++;
903 		} else {
904 			/* NB: in particular this captures ack's */
905 			ieee80211_radiotap_rx_all(ic, m);
906 		}
907 		m_freem(m); m = NULL;
908 		goto rx_next;
909 	}
910 
911 	if (IFF_DUMPPKTS(sc, ATH_DEBUG_RECV)) {
912 		const HAL_RATE_TABLE *rt = sc->sc_currates;
913 		uint8_t rix = rt->rateCodeToIndex[rs->rs_rate];
914 
915 		ieee80211_dump_pkt(ic, mtod(m, caddr_t), len,
916 		    sc->sc_hwmap[rix].ieeerate, rs->rs_rssi);
917 	}
918 
919 	m_adj(m, -IEEE80211_CRC_LEN);
920 
921 	/*
922 	 * Locate the node for sender, track state, and then
923 	 * pass the (referenced) node up to the 802.11 layer
924 	 * for its use.
925 	 */
926 	ni = ieee80211_find_rxnode_withkey(ic,
927 		mtod(m, const struct ieee80211_frame_min *),
928 		rs->rs_keyix == HAL_RXKEYIX_INVALID ?
929 			IEEE80211_KEYIX_NONE : rs->rs_keyix);
930 	sc->sc_lastrs = rs;
931 
932 	if (rs->rs_isaggr)
933 		sc->sc_stats.ast_rx_agg++;
934 
935 	/*
936 	 * Populate the per-chain RSSI values where appropriate.
937 	 */
938 	bzero(&rxs, sizeof(rxs));
939 	rxs.r_flags |= IEEE80211_R_NF | IEEE80211_R_RSSI |
940 	    IEEE80211_R_C_CHAIN |
941 	    IEEE80211_R_C_NF |
942 	    IEEE80211_R_C_RSSI |
943 	    IEEE80211_R_TSF64 |
944 	    IEEE80211_R_TSF_START;	/* XXX TODO: validate */
945 	rxs.c_rssi = rs->rs_rssi;
946 	rxs.c_nf = nf;
947 	rxs.c_chain = 3;	/* XXX TODO: check */
948 	rxs.c_rx_tsf = rstamp;
949 
950 	for (i = 0; i < 3; i++) {
951 		rxs.c_rssi_ctl[i] = rs->rs_rssi_ctl[i];
952 		rxs.c_rssi_ext[i] = rs->rs_rssi_ext[i];
953 		/*
954 		 * XXX note: we currently don't track
955 		 * per-chain noisefloor.
956 		 */
957 		rxs.c_nf_ctl[i] = nf;
958 		rxs.c_nf_ext[i] = nf;
959 	}
960 
961 	if (ni != NULL) {
962 		/*
963 		 * Only punt packets for ampdu reorder processing for
964 		 * 11n nodes; net80211 enforces that M_AMPDU is only
965 		 * set for 11n nodes.
966 		 */
967 		if (ni->ni_flags & IEEE80211_NODE_HT)
968 			m->m_flags |= M_AMPDU;
969 
970 		/*
971 		 * Inform rate control about the received RSSI.
972 		 * It can then use this information to potentially drastically
973 		 * alter the available rate based on the RSSI estimate.
974 		 *
975 		 * This is super important when associating to a far away station;
976 		 * you don't want to waste time trying higher rates at some low
977 		 * packet exchange rate (like during DHCP) just to establish
978 		 * that higher MCS rates aren't available.
979 		 */
980 		ATH_RSSI_LPF(ATH_NODE(ni)->an_node_stats.ns_avgrssi,
981 		    rs->rs_rssi);
982 		ath_rate_update_rx_rssi(sc, ATH_NODE(ni),
983 		    ATH_RSSI(ATH_NODE(ni)->an_node_stats.ns_avgrssi));
984 
985 		/*
986 		 * Sending station is known, dispatch directly.
987 		 */
988 		(void) ieee80211_add_rx_params(m, &rxs);
989 		type = ieee80211_input_mimo(ni, m);
990 		ieee80211_free_node(ni);
991 		m = NULL;
992 		/*
993 		 * Arrange to update the last rx timestamp only for
994 		 * frames from our ap when operating in station mode.
995 		 * This assumes the rx key is always setup when
996 		 * associated.
997 		 */
998 		if (ic->ic_opmode == IEEE80211_M_STA &&
999 		    rs->rs_keyix != HAL_RXKEYIX_INVALID)
1000 			is_good = 1;
1001 	} else {
1002 		(void) ieee80211_add_rx_params(m, &rxs);
1003 		type = ieee80211_input_mimo_all(ic, m);
1004 		m = NULL;
1005 	}
1006 
1007 	/*
1008 	 * At this point we have passed the frame up the stack; thus
1009 	 * the mbuf is no longer ours.
1010 	 */
1011 
1012 	/*
1013 	 * Track legacy station RX rssi and do any rx antenna management.
1014 	 */
1015 	ATH_RSSI_LPF(sc->sc_halstats.ns_avgrssi, rs->rs_rssi);
1016 	if (sc->sc_diversity) {
1017 		/*
1018 		 * When using fast diversity, change the default rx
1019 		 * antenna if diversity chooses the other antenna 3
1020 		 * times in a row.
1021 		 */
1022 		if (sc->sc_defant != rs->rs_antenna) {
1023 			if (++sc->sc_rxotherant >= 3)
1024 				ath_setdefantenna(sc, rs->rs_antenna);
1025 		} else
1026 			sc->sc_rxotherant = 0;
1027 	}
1028 
1029 	/* Handle slow diversity if enabled */
1030 	if (sc->sc_dolnadiv) {
1031 		ath_lna_rx_comb_scan(sc, rs, ticks, hz);
1032 	}
1033 
1034 	if (sc->sc_softled) {
1035 		/*
1036 		 * Blink for any data frame.  Otherwise do a
1037 		 * heartbeat-style blink when idle.  The latter
1038 		 * is mainly for station mode where we depend on
1039 		 * periodic beacon frames to trigger the poll event.
1040 		 */
1041 		if (type == IEEE80211_FC0_TYPE_DATA) {
1042 			const HAL_RATE_TABLE *rt = sc->sc_currates;
1043 			ath_led_event(sc,
1044 			    rt->rateCodeToIndex[rs->rs_rate]);
1045 		} else if (ticks - sc->sc_ledevent >= sc->sc_ledidle)
1046 			ath_led_event(sc, 0);
1047 		}
1048 rx_next:
1049 	/*
1050 	 * Debugging - complain if we didn't NULL the mbuf pointer
1051 	 * here.
1052 	 */
1053 	if (m != NULL) {
1054 		device_printf(sc->sc_dev,
1055 		    "%s: mbuf %p should've been freed!\n",
1056 		    __func__,
1057 		    m);
1058 	}
1059 	return (is_good);
1060 }
1061 
1062 #define	ATH_RX_MAX		128
1063 
1064 /*
1065  * XXX TODO: break out the "get buffers" from "call ath_rx_pkt()" like
1066  * the EDMA code does.
1067  *
1068  * XXX TODO: then, do all of the RX list management stuff inside
1069  * ATH_RX_LOCK() so we don't end up potentially racing.  The EDMA
1070  * code is doing it right.
1071  */
1072 static void
1073 ath_rx_proc(struct ath_softc *sc, int resched)
1074 {
1075 #define	PA2DESC(_sc, _pa) \
1076 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
1077 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
1078 	struct ath_buf *bf;
1079 	struct ath_hal *ah = sc->sc_ah;
1080 #ifdef IEEE80211_SUPPORT_SUPERG
1081 	struct ieee80211com *ic = &sc->sc_ic;
1082 #endif
1083 	struct ath_desc *ds;
1084 	struct ath_rx_status *rs;
1085 	struct mbuf *m;
1086 	int ngood;
1087 	HAL_STATUS status;
1088 	int16_t nf;
1089 	u_int64_t tsf;
1090 	int npkts = 0;
1091 	int kickpcu = 0;
1092 	int ret;
1093 
1094 	NET_EPOCH_ASSERT();
1095 
1096 	/* XXX we must not hold the ATH_LOCK here */
1097 	ATH_UNLOCK_ASSERT(sc);
1098 	ATH_PCU_UNLOCK_ASSERT(sc);
1099 
1100 	ATH_PCU_LOCK(sc);
1101 	sc->sc_rxproc_cnt++;
1102 	kickpcu = sc->sc_kickpcu;
1103 	ATH_PCU_UNLOCK(sc);
1104 
1105 	ATH_LOCK(sc);
1106 	ath_power_set_power_state(sc, HAL_PM_AWAKE);
1107 	ATH_UNLOCK(sc);
1108 
1109 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: called\n", __func__);
1110 	ngood = 0;
1111 	nf = ath_hal_getchannoise(ah, sc->sc_curchan);
1112 	sc->sc_stats.ast_rx_noise = nf;
1113 	tsf = ath_hal_gettsf64(ah);
1114 	do {
1115 		/*
1116 		 * Don't process too many packets at a time; give the
1117 		 * TX thread time to also run - otherwise the TX
1118 		 * latency can jump by quite a bit, causing throughput
1119 		 * degredation.
1120 		 */
1121 		if (!kickpcu && npkts >= ATH_RX_MAX)
1122 			break;
1123 
1124 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1125 		if (sc->sc_rxslink && bf == NULL) {	/* NB: shouldn't happen */
1126 			device_printf(sc->sc_dev, "%s: no buffer!\n", __func__);
1127 			break;
1128 		} else if (bf == NULL) {
1129 			/*
1130 			 * End of List:
1131 			 * this can happen for non-self-linked RX chains
1132 			 */
1133 			sc->sc_stats.ast_rx_hitqueueend++;
1134 			break;
1135 		}
1136 		m = bf->bf_m;
1137 		if (m == NULL) {		/* NB: shouldn't happen */
1138 			/*
1139 			 * If mbuf allocation failed previously there
1140 			 * will be no mbuf; try again to re-populate it.
1141 			 */
1142 			/* XXX make debug msg */
1143 			device_printf(sc->sc_dev, "%s: no mbuf!\n", __func__);
1144 			TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1145 			goto rx_proc_next;
1146 		}
1147 		ds = bf->bf_desc;
1148 		if (ds->ds_link == bf->bf_daddr) {
1149 			/* NB: never process the self-linked entry at the end */
1150 			sc->sc_stats.ast_rx_hitqueueend++;
1151 			break;
1152 		}
1153 		/* XXX sync descriptor memory */
1154 		/*
1155 		 * Must provide the virtual address of the current
1156 		 * descriptor, the physical address, and the virtual
1157 		 * address of the next descriptor in the h/w chain.
1158 		 * This allows the HAL to look ahead to see if the
1159 		 * hardware is done with a descriptor by checking the
1160 		 * done bit in the following descriptor and the address
1161 		 * of the current descriptor the DMA engine is working
1162 		 * on.  All this is necessary because of our use of
1163 		 * a self-linked list to avoid rx overruns.
1164 		 */
1165 		rs = &bf->bf_status.ds_rxstat;
1166 		status = ath_hal_rxprocdesc(ah, ds,
1167 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1168 #ifdef ATH_DEBUG
1169 		if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
1170 			ath_printrxbuf(sc, bf, 0, status == HAL_OK);
1171 #endif
1172 
1173 #ifdef	ATH_DEBUG_ALQ
1174 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS))
1175 		    if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS,
1176 		    sc->sc_rx_statuslen, (char *) ds);
1177 #endif	/* ATH_DEBUG_ALQ */
1178 
1179 		if (status == HAL_EINPROGRESS)
1180 			break;
1181 
1182 		TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1183 		npkts++;
1184 
1185 		/*
1186 		 * Process a single frame.
1187 		 */
1188 		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_POSTREAD);
1189 		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
1190 		bf->bf_m = NULL;
1191 		if (ath_rx_pkt(sc, rs, status, tsf, nf, HAL_RX_QUEUE_HP, bf, m))
1192 			ngood++;
1193 rx_proc_next:
1194 		/*
1195 		 * If there's a holding buffer, insert that onto
1196 		 * the RX list; the hardware is now definitely not pointing
1197 		 * to it now.
1198 		 */
1199 		ret = 0;
1200 		if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf != NULL) {
1201 			TAILQ_INSERT_TAIL(&sc->sc_rxbuf,
1202 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf,
1203 			    bf_list);
1204 			ret = ath_rxbuf_init(sc,
1205 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf);
1206 		}
1207 		/*
1208 		 * Next, throw our buffer into the holding entry.  The hardware
1209 		 * may use the descriptor to read the link pointer before
1210 		 * DMAing the next descriptor in to write out a packet.
1211 		 */
1212 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = bf;
1213 	} while (ret == 0);
1214 
1215 	/* rx signal state monitoring */
1216 	ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
1217 	if (ngood)
1218 		sc->sc_lastrx = tsf;
1219 
1220 	ATH_KTR(sc, ATH_KTR_RXPROC, 2, "ath_rx_proc: npkts=%d, ngood=%d", npkts, ngood);
1221 	/* Queue DFS tasklet if needed */
1222 	if (resched && ath_dfs_tasklet_needed(sc, sc->sc_curchan))
1223 		taskqueue_enqueue(sc->sc_tq, &sc->sc_dfstask);
1224 
1225 	/*
1226 	 * Now that all the RX frames were handled that
1227 	 * need to be handled, kick the PCU if there's
1228 	 * been an RXEOL condition.
1229 	 */
1230 	if (resched && kickpcu) {
1231 		ATH_PCU_LOCK(sc);
1232 		ATH_KTR(sc, ATH_KTR_ERROR, 0, "ath_rx_proc: kickpcu");
1233 		device_printf(sc->sc_dev, "%s: kickpcu; handled %d packets\n",
1234 		    __func__, npkts);
1235 
1236 		/*
1237 		 * Go through the process of fully tearing down
1238 		 * the RX buffers and reinitialising them.
1239 		 *
1240 		 * There's a hardware bug that causes the RX FIFO
1241 		 * to get confused under certain conditions and
1242 		 * constantly write over the same frame, leading
1243 		 * the RX driver code here to get heavily confused.
1244 		 */
1245 		/*
1246 		 * XXX Has RX DMA stopped enough here to just call
1247 		 *     ath_startrecv()?
1248 		 * XXX Do we need to use the holding buffer to restart
1249 		 *     RX DMA by appending entries to the final
1250 		 *     descriptor?  Quite likely.
1251 		 */
1252 #if 1
1253 		ath_startrecv(sc);
1254 #else
1255 		/*
1256 		 * Disabled for now - it'd be nice to be able to do
1257 		 * this in order to limit the amount of CPU time spent
1258 		 * reinitialising the RX side (and thus minimise RX
1259 		 * drops) however there's a hardware issue that
1260 		 * causes things to get too far out of whack.
1261 		 */
1262 		/*
1263 		 * XXX can we hold the PCU lock here?
1264 		 * Are there any net80211 buffer calls involved?
1265 		 */
1266 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1267 		ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1268 		ath_hal_rxena(ah);		/* enable recv descriptors */
1269 		ath_mode_init(sc);		/* set filters, etc. */
1270 		ath_hal_startpcurecv(ah, (!! sc->sc_scanning));	/* re-enable PCU/DMA engine */
1271 #endif
1272 
1273 		ath_hal_intrset(ah, sc->sc_imask);
1274 		sc->sc_kickpcu = 0;
1275 		ATH_PCU_UNLOCK(sc);
1276 	}
1277 
1278 #ifdef IEEE80211_SUPPORT_SUPERG
1279 	if (resched)
1280 		ieee80211_ff_age_all(ic, 100);
1281 #endif
1282 
1283 	/*
1284 	 * Put the hardware to sleep again if we're done with it.
1285 	 */
1286 	ATH_LOCK(sc);
1287 	ath_power_restore_power_state(sc);
1288 	ATH_UNLOCK(sc);
1289 
1290 	/*
1291 	 * If we hit the maximum number of frames in this round,
1292 	 * reschedule for another immediate pass.  This gives
1293 	 * the TX and TX completion routines time to run, which
1294 	 * will reduce latency.
1295 	 */
1296 	if (npkts >= ATH_RX_MAX)
1297 		sc->sc_rx.recv_sched(sc, resched);
1298 
1299 	ATH_PCU_LOCK(sc);
1300 	sc->sc_rxproc_cnt--;
1301 	ATH_PCU_UNLOCK(sc);
1302 }
1303 #undef	PA2DESC
1304 #undef	ATH_RX_MAX
1305 
1306 /*
1307  * Only run the RX proc if it's not already running.
1308  * Since this may get run as part of the reset/flush path,
1309  * the task can't clash with an existing, running tasklet.
1310  */
1311 static void
1312 ath_legacy_rx_tasklet(void *arg, int npending)
1313 {
1314 	struct ath_softc *sc = arg;
1315 	struct epoch_tracker et;
1316 
1317 	ATH_KTR(sc, ATH_KTR_RXPROC, 1, "ath_rx_proc: pending=%d", npending);
1318 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: pending %u\n", __func__, npending);
1319 	ATH_PCU_LOCK(sc);
1320 	if (sc->sc_inreset_cnt > 0) {
1321 		device_printf(sc->sc_dev,
1322 		    "%s: sc_inreset_cnt > 0; skipping\n", __func__);
1323 		ATH_PCU_UNLOCK(sc);
1324 		return;
1325 	}
1326 	ATH_PCU_UNLOCK(sc);
1327 
1328 	NET_EPOCH_ENTER(et);
1329 	ath_rx_proc(sc, 1);
1330 	NET_EPOCH_EXIT(et);
1331 }
1332 
1333 static void
1334 ath_legacy_flushrecv(struct ath_softc *sc)
1335 {
1336 	struct epoch_tracker et;
1337 	NET_EPOCH_ENTER(et);
1338 	ath_rx_proc(sc, 0);
1339 	NET_EPOCH_EXIT(et);
1340 }
1341 
1342 static void
1343 ath_legacy_flush_rxpending(struct ath_softc *sc)
1344 {
1345 
1346 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1347 
1348 	if (sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending != NULL) {
1349 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending);
1350 		sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending = NULL;
1351 	}
1352 	if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending != NULL) {
1353 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending);
1354 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending = NULL;
1355 	}
1356 }
1357 
1358 static int
1359 ath_legacy_flush_rxholdbf(struct ath_softc *sc)
1360 {
1361 	struct ath_buf *bf;
1362 
1363 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1364 	/*
1365 	 * If there are RX holding buffers, free them here and return
1366 	 * them to the list.
1367 	 *
1368 	 * XXX should just verify that bf->bf_m is NULL, as it must
1369 	 * be at this point!
1370 	 */
1371 	bf = sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf;
1372 	if (bf != NULL) {
1373 		if (bf->bf_m != NULL)
1374 			m_freem(bf->bf_m);
1375 		bf->bf_m = NULL;
1376 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1377 		(void) ath_rxbuf_init(sc, bf);
1378 	}
1379 	sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = NULL;
1380 
1381 	bf = sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf;
1382 	if (bf != NULL) {
1383 		if (bf->bf_m != NULL)
1384 			m_freem(bf->bf_m);
1385 		bf->bf_m = NULL;
1386 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1387 		(void) ath_rxbuf_init(sc, bf);
1388 	}
1389 	sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf = NULL;
1390 
1391 	return (0);
1392 }
1393 
1394 /*
1395  * Disable the receive h/w in preparation for a reset.
1396  */
1397 static void
1398 ath_legacy_stoprecv(struct ath_softc *sc, int dodelay)
1399 {
1400 #define	PA2DESC(_sc, _pa) \
1401 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
1402 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
1403 	struct ath_hal *ah = sc->sc_ah;
1404 
1405 	ATH_RX_LOCK(sc);
1406 
1407 	ath_hal_stoppcurecv(ah);	/* disable PCU */
1408 	ath_hal_setrxfilter(ah, 0);	/* clear recv filter */
1409 	ath_hal_stopdmarecv(ah);	/* disable DMA engine */
1410 	/*
1411 	 * TODO: see if this particular DELAY() is required; it may be
1412 	 * masking some missing FIFO flush or DMA sync.
1413 	 */
1414 #if 0
1415 	if (dodelay)
1416 #endif
1417 		DELAY(3000);		/* 3ms is long enough for 1 frame */
1418 #ifdef ATH_DEBUG
1419 	if (sc->sc_debug & (ATH_DEBUG_RESET | ATH_DEBUG_FATAL)) {
1420 		struct ath_buf *bf;
1421 		u_int ix;
1422 
1423 		device_printf(sc->sc_dev,
1424 		    "%s: rx queue %p, link %p\n",
1425 		    __func__,
1426 		    (caddr_t)(uintptr_t) ath_hal_getrxbuf(ah, HAL_RX_QUEUE_HP),
1427 		    sc->sc_rxlink);
1428 		ix = 0;
1429 		TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1430 			struct ath_desc *ds = bf->bf_desc;
1431 			struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
1432 			HAL_STATUS status = ath_hal_rxprocdesc(ah, ds,
1433 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1434 			if (status == HAL_OK || (sc->sc_debug & ATH_DEBUG_FATAL))
1435 				ath_printrxbuf(sc, bf, ix, status == HAL_OK);
1436 			ix++;
1437 		}
1438 	}
1439 #endif
1440 
1441 	(void) ath_legacy_flush_rxpending(sc);
1442 	(void) ath_legacy_flush_rxholdbf(sc);
1443 
1444 	sc->sc_rxlink = NULL;		/* just in case */
1445 
1446 	ATH_RX_UNLOCK(sc);
1447 #undef PA2DESC
1448 }
1449 
1450 /*
1451  * XXX TODO: something was calling startrecv without calling
1452  * stoprecv.  Let's figure out what/why.  It was showing up
1453  * as a mbuf leak (rxpending) and ath_buf leak (holdbf.)
1454  */
1455 
1456 /*
1457  * Enable the receive h/w following a reset.
1458  */
1459 static int
1460 ath_legacy_startrecv(struct ath_softc *sc)
1461 {
1462 	struct ath_hal *ah = sc->sc_ah;
1463 	struct ath_buf *bf;
1464 
1465 	ATH_RX_LOCK(sc);
1466 
1467 	/*
1468 	 * XXX should verify these are already all NULL!
1469 	 */
1470 	sc->sc_rxlink = NULL;
1471 	(void) ath_legacy_flush_rxpending(sc);
1472 	(void) ath_legacy_flush_rxholdbf(sc);
1473 
1474 	/*
1475 	 * Re-chain all of the buffers in the RX buffer list.
1476 	 */
1477 	TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1478 		int error = ath_rxbuf_init(sc, bf);
1479 		if (error != 0) {
1480 			DPRINTF(sc, ATH_DEBUG_RECV,
1481 				"%s: ath_rxbuf_init failed %d\n",
1482 				__func__, error);
1483 			return error;
1484 		}
1485 	}
1486 
1487 	bf = TAILQ_FIRST(&sc->sc_rxbuf);
1488 	ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1489 	ath_hal_rxena(ah);		/* enable recv descriptors */
1490 	ath_mode_init(sc);		/* set filters, etc. */
1491 	ath_hal_startpcurecv(ah, (!! sc->sc_scanning));	/* re-enable PCU/DMA engine */
1492 
1493 	ATH_RX_UNLOCK(sc);
1494 	return 0;
1495 }
1496 
1497 static int
1498 ath_legacy_dma_rxsetup(struct ath_softc *sc)
1499 {
1500 	int error;
1501 
1502 	error = ath_descdma_setup(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
1503 	    "rx", sizeof(struct ath_desc), ath_rxbuf, 1);
1504 	if (error != 0)
1505 		return (error);
1506 
1507 	return (0);
1508 }
1509 
1510 static int
1511 ath_legacy_dma_rxteardown(struct ath_softc *sc)
1512 {
1513 
1514 	if (sc->sc_rxdma.dd_desc_len != 0)
1515 		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
1516 	return (0);
1517 }
1518 
1519 static void
1520 ath_legacy_recv_sched(struct ath_softc *sc, int dosched)
1521 {
1522 
1523 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1524 }
1525 
1526 static void
1527 ath_legacy_recv_sched_queue(struct ath_softc *sc, HAL_RX_QUEUE q,
1528     int dosched)
1529 {
1530 
1531 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1532 }
1533 
1534 void
1535 ath_recv_setup_legacy(struct ath_softc *sc)
1536 {
1537 
1538 	/* Sensible legacy defaults */
1539 	/*
1540 	 * XXX this should be changed to properly support the
1541 	 * exact RX descriptor size for each HAL.
1542 	 */
1543 	sc->sc_rx_statuslen = sizeof(struct ath_desc);
1544 
1545 	sc->sc_rx.recv_start = ath_legacy_startrecv;
1546 	sc->sc_rx.recv_stop = ath_legacy_stoprecv;
1547 	sc->sc_rx.recv_flush = ath_legacy_flushrecv;
1548 	sc->sc_rx.recv_tasklet = ath_legacy_rx_tasklet;
1549 	sc->sc_rx.recv_rxbuf_init = ath_legacy_rxbuf_init;
1550 
1551 	sc->sc_rx.recv_setup = ath_legacy_dma_rxsetup;
1552 	sc->sc_rx.recv_teardown = ath_legacy_dma_rxteardown;
1553 	sc->sc_rx.recv_sched = ath_legacy_recv_sched;
1554 	sc->sc_rx.recv_sched_queue = ath_legacy_recv_sched_queue;
1555 }
1556