xref: /freebsd/sys/dev/ath/if_ath_rx.c (revision 6829dae12bb055451fa467da4589c43bd03b1e64)
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 		/*
368 		 * Only do the following processing if it's for
369 		 * the current BSS.
370 		 *
371 		 * In scan and IBSS mode we receive all beacons,
372 		 * which means we need to filter out stuff
373 		 * that isn't for us or we'll end up constantly
374 		 * trying to sync / merge to BSSes that aren't
375 		 * actually us.
376 		 */
377 		if (IEEE80211_ADDR_EQ(ni->ni_bssid, vap->iv_bss->ni_bssid)) {
378 			/* update rssi statistics for use by the hal */
379 			/* XXX unlocked check against vap->iv_bss? */
380 			ATH_RSSI_LPF(sc->sc_halstats.ns_avgbrssi, rssi);
381 
382 
383 			tsf_beacon = ((uint64_t) le32dec(ni->ni_tstamp.data + 4)) << 32;
384 			tsf_beacon |= le32dec(ni->ni_tstamp.data);
385 
386 			nexttbtt = ath_hal_getnexttbtt(sc->sc_ah);
387 
388 			/*
389 			 * Let's calculate the delta and remainder, so we can see
390 			 * if the beacon timer from the AP is varying by more than
391 			 * a few TU.  (Which would be a huge, huge problem.)
392 			 */
393 			tsf_delta = (long long) tsf_beacon - (long long) tsf_beacon_old;
394 
395 			tsf_delta_bmiss = tsf_delta / tsf_intval;
396 
397 			/*
398 			 * If our delta is greater than half the beacon interval,
399 			 * let's round the bmiss value up to the next beacon
400 			 * interval.  Ie, we're running really, really early
401 			 * on the next beacon.
402 			 */
403 			if (tsf_delta % tsf_intval > (tsf_intval / 2))
404 				tsf_delta_bmiss ++;
405 
406 			tsf_beacon_target = tsf_beacon_old +
407 			    (((unsigned long long) tsf_delta_bmiss) * (long long) tsf_intval);
408 
409 			/*
410 			 * The remainder using '%' is between 0 .. intval-1.
411 			 * If we're actually running too fast, then the remainder
412 			 * will be some large number just under intval-1.
413 			 * So we need to look at whether we're running
414 			 * before or after the target beacon interval
415 			 * and if we are, modify how we do the remainder
416 			 * calculation.
417 			 */
418 			if (tsf_beacon < tsf_beacon_target) {
419 				tsf_remainder =
420 				    -(tsf_intval - ((tsf_beacon - tsf_beacon_old) % tsf_intval));
421 			} else {
422 				tsf_remainder = (tsf_beacon - tsf_beacon_old) % tsf_intval;
423 			}
424 
425 			DPRINTF(sc, ATH_DEBUG_BEACON, "%s: old_tsf=%llu (%u), new_tsf=%llu (%u), target_tsf=%llu (%u), delta=%lld, bmiss=%d, remainder=%d\n",
426 			    __func__,
427 			    (unsigned long long) tsf_beacon_old,
428 			    (unsigned int) (tsf_beacon_old >> 10),
429 			    (unsigned long long) tsf_beacon,
430 			    (unsigned int ) (tsf_beacon >> 10),
431 			    (unsigned long long) tsf_beacon_target,
432 			    (unsigned int) (tsf_beacon_target >> 10),
433 			    (long long) tsf_delta,
434 			    tsf_delta_bmiss,
435 			    tsf_remainder);
436 
437 			DPRINTF(sc, ATH_DEBUG_BEACON, "%s: tsf=%llu (%u), nexttbtt=%llu (%u), delta=%d\n",
438 			    __func__,
439 			    (unsigned long long) tsf_beacon,
440 			    (unsigned int) (tsf_beacon >> 10),
441 			    (unsigned long long) nexttbtt,
442 			    (unsigned int) (nexttbtt >> 10),
443 			    (int32_t) tsf_beacon - (int32_t) nexttbtt + tsf_intval);
444 
445 			/* We only do syncbeacon on STA VAPs; not on IBSS */
446 			if (vap->iv_opmode == IEEE80211_M_STA &&
447 			    sc->sc_syncbeacon &&
448 			    ni == vap->iv_bss &&
449 			    (vap->iv_state == IEEE80211_S_RUN || vap->iv_state == IEEE80211_S_SLEEP)) {
450 				DPRINTF(sc, ATH_DEBUG_BEACON,
451 				    "%s: syncbeacon=1; syncing\n",
452 				    __func__);
453 				/*
454 				 * Resync beacon timers using the tsf of the beacon
455 				 * frame we just received.
456 				 */
457 				ath_beacon_config(sc, vap);
458 				sc->sc_syncbeacon = 0;
459 			}
460 		}
461 
462 		/* fall thru... */
463 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
464 		if (vap->iv_opmode == IEEE80211_M_IBSS &&
465 		    vap->iv_state == IEEE80211_S_RUN &&
466 		    ieee80211_ibss_merge_check(ni)) {
467 			uint32_t rstamp = sc->sc_lastrs->rs_tstamp;
468 			uint64_t tsf = ath_extend_tsf(sc, rstamp,
469 				ath_hal_gettsf64(sc->sc_ah));
470 			/*
471 			 * Handle ibss merge as needed; check the tsf on the
472 			 * frame before attempting the merge.  The 802.11 spec
473 			 * says the station should change it's bssid to match
474 			 * the oldest station with the same ssid, where oldest
475 			 * is determined by the tsf.  Note that hardware
476 			 * reconfiguration happens through callback to
477 			 * ath_newstate as the state machine will go from
478 			 * RUN -> RUN when this happens.
479 			 */
480 			if (le64toh(ni->ni_tstamp.tsf) >= tsf) {
481 				DPRINTF(sc, ATH_DEBUG_STATE,
482 				    "ibss merge, rstamp %u tsf %ju "
483 				    "tstamp %ju\n", rstamp, (uintmax_t)tsf,
484 				    (uintmax_t)ni->ni_tstamp.tsf);
485 				(void) ieee80211_ibss_merge(ni);
486 			}
487 		}
488 		break;
489 	}
490 }
491 
492 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
493 static void
494 ath_rx_tap_vendor(struct ath_softc *sc, struct mbuf *m,
495     const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
496 {
497 
498 	/* Fill in the extension bitmap */
499 	sc->sc_rx_th.wr_ext_bitmap = htole32(1 << ATH_RADIOTAP_VENDOR_HEADER);
500 
501 	/* Fill in the vendor header */
502 	sc->sc_rx_th.wr_vh.vh_oui[0] = 0x7f;
503 	sc->sc_rx_th.wr_vh.vh_oui[1] = 0x03;
504 	sc->sc_rx_th.wr_vh.vh_oui[2] = 0x00;
505 
506 	/* XXX what should this be? */
507 	sc->sc_rx_th.wr_vh.vh_sub_ns = 0;
508 	sc->sc_rx_th.wr_vh.vh_skip_len =
509 	    htole16(sizeof(struct ath_radiotap_vendor_hdr));
510 
511 	/* General version info */
512 	sc->sc_rx_th.wr_v.vh_version = 1;
513 
514 	sc->sc_rx_th.wr_v.vh_rx_chainmask = sc->sc_rxchainmask;
515 
516 	/* rssi */
517 	sc->sc_rx_th.wr_v.rssi_ctl[0] = rs->rs_rssi_ctl[0];
518 	sc->sc_rx_th.wr_v.rssi_ctl[1] = rs->rs_rssi_ctl[1];
519 	sc->sc_rx_th.wr_v.rssi_ctl[2] = rs->rs_rssi_ctl[2];
520 	sc->sc_rx_th.wr_v.rssi_ext[0] = rs->rs_rssi_ext[0];
521 	sc->sc_rx_th.wr_v.rssi_ext[1] = rs->rs_rssi_ext[1];
522 	sc->sc_rx_th.wr_v.rssi_ext[2] = rs->rs_rssi_ext[2];
523 
524 	/* evm */
525 	sc->sc_rx_th.wr_v.evm[0] = rs->rs_evm0;
526 	sc->sc_rx_th.wr_v.evm[1] = rs->rs_evm1;
527 	sc->sc_rx_th.wr_v.evm[2] = rs->rs_evm2;
528 	/* These are only populated from the AR9300 or later */
529 	sc->sc_rx_th.wr_v.evm[3] = rs->rs_evm3;
530 	sc->sc_rx_th.wr_v.evm[4] = rs->rs_evm4;
531 
532 	/* direction */
533 	sc->sc_rx_th.wr_v.vh_flags = ATH_VENDOR_PKT_RX;
534 
535 	/* RX rate */
536 	sc->sc_rx_th.wr_v.vh_rx_hwrate = rs->rs_rate;
537 
538 	/* RX flags */
539 	sc->sc_rx_th.wr_v.vh_rs_flags = rs->rs_flags;
540 
541 	if (rs->rs_isaggr)
542 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_ISAGGR;
543 	if (rs->rs_moreaggr)
544 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_MOREAGGR;
545 
546 	/* phyerr info */
547 	if (rs->rs_status & HAL_RXERR_PHY) {
548 		sc->sc_rx_th.wr_v.vh_phyerr_code = rs->rs_phyerr;
549 		sc->sc_rx_th.wr_v.vh_flags |= ATH_VENDOR_PKT_RXPHYERR;
550 	} else {
551 		sc->sc_rx_th.wr_v.vh_phyerr_code = 0xff;
552 	}
553 	sc->sc_rx_th.wr_v.vh_rs_status = rs->rs_status;
554 	sc->sc_rx_th.wr_v.vh_rssi = rs->rs_rssi;
555 }
556 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
557 
558 static void
559 ath_rx_tap(struct ath_softc *sc, struct mbuf *m,
560 	const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
561 {
562 #define	CHAN_HT20	htole32(IEEE80211_CHAN_HT20)
563 #define	CHAN_HT40U	htole32(IEEE80211_CHAN_HT40U)
564 #define	CHAN_HT40D	htole32(IEEE80211_CHAN_HT40D)
565 #define	CHAN_HT		(CHAN_HT20|CHAN_HT40U|CHAN_HT40D)
566 	const HAL_RATE_TABLE *rt;
567 	uint8_t rix;
568 
569 	rt = sc->sc_currates;
570 	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
571 	rix = rt->rateCodeToIndex[rs->rs_rate];
572 	sc->sc_rx_th.wr_rate = sc->sc_hwmap[rix].ieeerate;
573 	sc->sc_rx_th.wr_flags = sc->sc_hwmap[rix].rxflags;
574 
575 	/* 802.11 specific flags */
576 	sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT;
577 	if (rs->rs_status & HAL_RXERR_PHY) {
578 		/*
579 		 * PHY error - make sure the channel flags
580 		 * reflect the actual channel configuration,
581 		 * not the received frame.
582 		 */
583 		if (IEEE80211_IS_CHAN_HT40U(sc->sc_curchan))
584 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
585 		else if (IEEE80211_IS_CHAN_HT40D(sc->sc_curchan))
586 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
587 		else if (IEEE80211_IS_CHAN_HT20(sc->sc_curchan))
588 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
589 	} else if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) {	/* HT rate */
590 		struct ieee80211com *ic = &sc->sc_ic;
591 
592 		if ((rs->rs_flags & HAL_RX_2040) == 0)
593 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
594 		else if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan))
595 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
596 		else
597 			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
598 
599 		if (rs->rs_flags & HAL_RX_GI)
600 			sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_SHORTGI;
601 	}
602 
603 	sc->sc_rx_th.wr_tsf = htole64(ath_extend_tsf(sc, rs->rs_tstamp, tsf));
604 	if (rs->rs_status & HAL_RXERR_CRC)
605 		sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_BADFCS;
606 	/* XXX propagate other error flags from descriptor */
607 	sc->sc_rx_th.wr_antnoise = nf;
608 	sc->sc_rx_th.wr_antsignal = nf + rs->rs_rssi;
609 	sc->sc_rx_th.wr_antenna = rs->rs_antenna;
610 #undef CHAN_HT
611 #undef CHAN_HT20
612 #undef CHAN_HT40U
613 #undef CHAN_HT40D
614 }
615 
616 static void
617 ath_handle_micerror(struct ieee80211com *ic,
618 	struct ieee80211_frame *wh, int keyix)
619 {
620 	struct ieee80211_node *ni;
621 
622 	/* XXX recheck MIC to deal w/ chips that lie */
623 	/* XXX discard MIC errors on !data frames */
624 	ni = ieee80211_find_rxnode(ic, (const struct ieee80211_frame_min *) wh);
625 	if (ni != NULL) {
626 		ieee80211_notify_michael_failure(ni->ni_vap, wh, keyix);
627 		ieee80211_free_node(ni);
628 	}
629 }
630 
631 /*
632  * Process a single packet.
633  *
634  * The mbuf must already be synced, unmapped and removed from bf->bf_m
635  * by this stage.
636  *
637  * The mbuf must be consumed by this routine - either passed up the
638  * net80211 stack, put on the holding queue, or freed.
639  */
640 int
641 ath_rx_pkt(struct ath_softc *sc, struct ath_rx_status *rs, HAL_STATUS status,
642     uint64_t tsf, int nf, HAL_RX_QUEUE qtype, struct ath_buf *bf,
643     struct mbuf *m)
644 {
645 	uint64_t rstamp;
646 	/* XXX TODO: make this an mbuf tag? */
647 	struct ieee80211_rx_stats rxs;
648 	int len, type, i;
649 	struct ieee80211com *ic = &sc->sc_ic;
650 	struct ieee80211_node *ni;
651 	int is_good = 0;
652 	struct ath_rx_edma *re = &sc->sc_rxedma[qtype];
653 
654 	/*
655 	 * Calculate the correct 64 bit TSF given
656 	 * the TSF64 register value and rs_tstamp.
657 	 */
658 	rstamp = ath_extend_tsf(sc, rs->rs_tstamp, tsf);
659 
660 	/* 802.11 return codes - These aren't specifically errors */
661 	if (rs->rs_flags & HAL_RX_GI)
662 		sc->sc_stats.ast_rx_halfgi++;
663 	if (rs->rs_flags & HAL_RX_2040)
664 		sc->sc_stats.ast_rx_2040++;
665 	if (rs->rs_flags & HAL_RX_DELIM_CRC_PRE)
666 		sc->sc_stats.ast_rx_pre_crc_err++;
667 	if (rs->rs_flags & HAL_RX_DELIM_CRC_POST)
668 		sc->sc_stats.ast_rx_post_crc_err++;
669 	if (rs->rs_flags & HAL_RX_DECRYPT_BUSY)
670 		sc->sc_stats.ast_rx_decrypt_busy_err++;
671 	if (rs->rs_flags & HAL_RX_HI_RX_CHAIN)
672 		sc->sc_stats.ast_rx_hi_rx_chain++;
673 	if (rs->rs_flags & HAL_RX_STBC)
674 		sc->sc_stats.ast_rx_stbc++;
675 
676 	if (rs->rs_status != 0) {
677 		if (rs->rs_status & HAL_RXERR_CRC)
678 			sc->sc_stats.ast_rx_crcerr++;
679 		if (rs->rs_status & HAL_RXERR_FIFO)
680 			sc->sc_stats.ast_rx_fifoerr++;
681 		if (rs->rs_status & HAL_RXERR_PHY) {
682 			sc->sc_stats.ast_rx_phyerr++;
683 			/* Process DFS radar events */
684 			if ((rs->rs_phyerr == HAL_PHYERR_RADAR) ||
685 			    (rs->rs_phyerr == HAL_PHYERR_FALSE_RADAR_EXT)) {
686 				/* Now pass it to the radar processing code */
687 				ath_dfs_process_phy_err(sc, m, rstamp, rs);
688 			}
689 
690 			/* Be suitably paranoid about receiving phy errors out of the stats array bounds */
691 			if (rs->rs_phyerr < 64)
692 				sc->sc_stats.ast_rx_phy[rs->rs_phyerr]++;
693 			goto rx_error;	/* NB: don't count in ierrors */
694 		}
695 		if (rs->rs_status & HAL_RXERR_DECRYPT) {
696 			/*
697 			 * Decrypt error.  If the error occurred
698 			 * because there was no hardware key, then
699 			 * let the frame through so the upper layers
700 			 * can process it.  This is necessary for 5210
701 			 * parts which have no way to setup a ``clear''
702 			 * key cache entry.
703 			 *
704 			 * XXX do key cache faulting
705 			 */
706 			if (rs->rs_keyix == HAL_RXKEYIX_INVALID)
707 				goto rx_accept;
708 			sc->sc_stats.ast_rx_badcrypt++;
709 		}
710 		/*
711 		 * Similar as above - if the failure was a keymiss
712 		 * just punt it up to the upper layers for now.
713 		 */
714 		if (rs->rs_status & HAL_RXERR_KEYMISS) {
715 			sc->sc_stats.ast_rx_keymiss++;
716 			goto rx_accept;
717 		}
718 		if (rs->rs_status & HAL_RXERR_MIC) {
719 			sc->sc_stats.ast_rx_badmic++;
720 			/*
721 			 * Do minimal work required to hand off
722 			 * the 802.11 header for notification.
723 			 */
724 			/* XXX frag's and qos frames */
725 			len = rs->rs_datalen;
726 			if (len >= sizeof (struct ieee80211_frame)) {
727 				ath_handle_micerror(ic,
728 				    mtod(m, struct ieee80211_frame *),
729 				    sc->sc_splitmic ?
730 					rs->rs_keyix-32 : rs->rs_keyix);
731 			}
732 		}
733 		counter_u64_add(ic->ic_ierrors, 1);
734 rx_error:
735 		/*
736 		 * Cleanup any pending partial frame.
737 		 */
738 		if (re->m_rxpending != NULL) {
739 			m_freem(re->m_rxpending);
740 			re->m_rxpending = NULL;
741 		}
742 		/*
743 		 * When a tap is present pass error frames
744 		 * that have been requested.  By default we
745 		 * pass decrypt+mic errors but others may be
746 		 * interesting (e.g. crc).
747 		 */
748 		if (ieee80211_radiotap_active(ic) &&
749 		    (rs->rs_status & sc->sc_monpass)) {
750 			/* NB: bpf needs the mbuf length setup */
751 			len = rs->rs_datalen;
752 			m->m_pkthdr.len = m->m_len = len;
753 			ath_rx_tap(sc, m, rs, rstamp, nf);
754 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
755 			ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
756 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
757 			ieee80211_radiotap_rx_all(ic, m);
758 		}
759 		/* XXX pass MIC errors up for s/w reclaculation */
760 		m_freem(m); m = NULL;
761 		goto rx_next;
762 	}
763 rx_accept:
764 	len = rs->rs_datalen;
765 	m->m_len = len;
766 
767 	if (rs->rs_more) {
768 		/*
769 		 * Frame spans multiple descriptors; save
770 		 * it for the next completed descriptor, it
771 		 * will be used to construct a jumbogram.
772 		 */
773 		if (re->m_rxpending != NULL) {
774 			/* NB: max frame size is currently 2 clusters */
775 			sc->sc_stats.ast_rx_toobig++;
776 			m_freem(re->m_rxpending);
777 		}
778 		m->m_pkthdr.len = len;
779 		re->m_rxpending = m;
780 		m = NULL;
781 		goto rx_next;
782 	} else if (re->m_rxpending != NULL) {
783 		/*
784 		 * This is the second part of a jumbogram,
785 		 * chain it to the first mbuf, adjust the
786 		 * frame length, and clear the rxpending state.
787 		 */
788 		re->m_rxpending->m_next = m;
789 		re->m_rxpending->m_pkthdr.len += len;
790 		m = re->m_rxpending;
791 		re->m_rxpending = NULL;
792 	} else {
793 		/*
794 		 * Normal single-descriptor receive; setup packet length.
795 		 */
796 		m->m_pkthdr.len = len;
797 	}
798 
799 	/*
800 	 * Validate rs->rs_antenna.
801 	 *
802 	 * Some users w/ AR9285 NICs have reported crashes
803 	 * here because rs_antenna field is bogusly large.
804 	 * Let's enforce the maximum antenna limit of 8
805 	 * (and it shouldn't be hard coded, but that's a
806 	 * separate problem) and if there's an issue, print
807 	 * out an error and adjust rs_antenna to something
808 	 * sensible.
809 	 *
810 	 * This code should be removed once the actual
811 	 * root cause of the issue has been identified.
812 	 * For example, it may be that the rs_antenna
813 	 * field is only valid for the last frame of
814 	 * an aggregate and it just happens that it is
815 	 * "mostly" right. (This is a general statement -
816 	 * the majority of the statistics are only valid
817 	 * for the last frame in an aggregate.
818 	 */
819 	if (rs->rs_antenna > 7) {
820 		device_printf(sc->sc_dev, "%s: rs_antenna > 7 (%d)\n",
821 		    __func__, rs->rs_antenna);
822 #ifdef	ATH_DEBUG
823 		ath_printrxbuf(sc, bf, 0, status == HAL_OK);
824 #endif /* ATH_DEBUG */
825 		rs->rs_antenna = 0;	/* XXX better than nothing */
826 	}
827 
828 	/*
829 	 * If this is an AR9285/AR9485, then the receive and LNA
830 	 * configuration is stored in RSSI[2] / EXTRSSI[2].
831 	 * We can extract this out to build a much better
832 	 * receive antenna profile.
833 	 *
834 	 * Yes, this just blurts over the above RX antenna field
835 	 * for now.  It's fine, the AR9285 doesn't really use
836 	 * that.
837 	 *
838 	 * Later on we should store away the fine grained LNA
839 	 * information and keep separate counters just for
840 	 * that.  It'll help when debugging the AR9285/AR9485
841 	 * combined diversity code.
842 	 */
843 	if (sc->sc_rx_lnamixer) {
844 		rs->rs_antenna = 0;
845 
846 		/* Bits 0:1 - the LNA configuration used */
847 		rs->rs_antenna |=
848 		    ((rs->rs_rssi_ctl[2] & HAL_RX_LNA_CFG_USED)
849 		      >> HAL_RX_LNA_CFG_USED_S);
850 
851 		/* Bit 2 - the external RX antenna switch */
852 		if (rs->rs_rssi_ctl[2] & HAL_RX_LNA_EXTCFG)
853 			rs->rs_antenna |= 0x4;
854 	}
855 
856 	sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;
857 
858 	/*
859 	 * Populate the rx status block.  When there are bpf
860 	 * listeners we do the additional work to provide
861 	 * complete status.  Otherwise we fill in only the
862 	 * material required by ieee80211_input.  Note that
863 	 * noise setting is filled in above.
864 	 */
865 	if (ieee80211_radiotap_active(ic)) {
866 		ath_rx_tap(sc, m, rs, rstamp, nf);
867 #ifdef	ATH_ENABLE_RADIOTAP_VENDOR_EXT
868 		ath_rx_tap_vendor(sc, m, rs, rstamp, nf);
869 #endif	/* ATH_ENABLE_RADIOTAP_VENDOR_EXT */
870 	}
871 
872 	/*
873 	 * From this point on we assume the frame is at least
874 	 * as large as ieee80211_frame_min; verify that.
875 	 */
876 	if (len < IEEE80211_MIN_LEN) {
877 		if (!ieee80211_radiotap_active(ic)) {
878 			DPRINTF(sc, ATH_DEBUG_RECV,
879 			    "%s: short packet %d\n", __func__, len);
880 			sc->sc_stats.ast_rx_tooshort++;
881 		} else {
882 			/* NB: in particular this captures ack's */
883 			ieee80211_radiotap_rx_all(ic, m);
884 		}
885 		m_freem(m); m = NULL;
886 		goto rx_next;
887 	}
888 
889 	if (IFF_DUMPPKTS(sc, ATH_DEBUG_RECV)) {
890 		const HAL_RATE_TABLE *rt = sc->sc_currates;
891 		uint8_t rix = rt->rateCodeToIndex[rs->rs_rate];
892 
893 		ieee80211_dump_pkt(ic, mtod(m, caddr_t), len,
894 		    sc->sc_hwmap[rix].ieeerate, rs->rs_rssi);
895 	}
896 
897 	m_adj(m, -IEEE80211_CRC_LEN);
898 
899 	/*
900 	 * Locate the node for sender, track state, and then
901 	 * pass the (referenced) node up to the 802.11 layer
902 	 * for its use.
903 	 */
904 	ni = ieee80211_find_rxnode_withkey(ic,
905 		mtod(m, const struct ieee80211_frame_min *),
906 		rs->rs_keyix == HAL_RXKEYIX_INVALID ?
907 			IEEE80211_KEYIX_NONE : rs->rs_keyix);
908 	sc->sc_lastrs = rs;
909 
910 	if (rs->rs_isaggr)
911 		sc->sc_stats.ast_rx_agg++;
912 
913 	/*
914 	 * Populate the per-chain RSSI values where appropriate.
915 	 */
916 	bzero(&rxs, sizeof(rxs));
917 	rxs.r_flags |= IEEE80211_R_NF | IEEE80211_R_RSSI |
918 	    IEEE80211_R_C_CHAIN |
919 	    IEEE80211_R_C_NF |
920 	    IEEE80211_R_C_RSSI |
921 	    IEEE80211_R_TSF64 |
922 	    IEEE80211_R_TSF_START;	/* XXX TODO: validate */
923 	rxs.c_rssi = rs->rs_rssi;
924 	rxs.c_nf = nf;
925 	rxs.c_chain = 3;	/* XXX TODO: check */
926 	rxs.c_rx_tsf = rstamp;
927 
928 	for (i = 0; i < 3; i++) {
929 		rxs.c_rssi_ctl[i] = rs->rs_rssi_ctl[i];
930 		rxs.c_rssi_ext[i] = rs->rs_rssi_ext[i];
931 		/*
932 		 * XXX note: we currently don't track
933 		 * per-chain noisefloor.
934 		 */
935 		rxs.c_nf_ctl[i] = nf;
936 		rxs.c_nf_ext[i] = nf;
937 	}
938 
939 	if (ni != NULL) {
940 		/*
941 		 * Only punt packets for ampdu reorder processing for
942 		 * 11n nodes; net80211 enforces that M_AMPDU is only
943 		 * set for 11n nodes.
944 		 */
945 		if (ni->ni_flags & IEEE80211_NODE_HT)
946 			m->m_flags |= M_AMPDU;
947 
948 		/*
949 		 * Sending station is known, dispatch directly.
950 		 */
951 		(void) ieee80211_add_rx_params(m, &rxs);
952 		type = ieee80211_input_mimo(ni, m);
953 		ieee80211_free_node(ni);
954 		m = NULL;
955 		/*
956 		 * Arrange to update the last rx timestamp only for
957 		 * frames from our ap when operating in station mode.
958 		 * This assumes the rx key is always setup when
959 		 * associated.
960 		 */
961 		if (ic->ic_opmode == IEEE80211_M_STA &&
962 		    rs->rs_keyix != HAL_RXKEYIX_INVALID)
963 			is_good = 1;
964 	} else {
965 		(void) ieee80211_add_rx_params(m, &rxs);
966 		type = ieee80211_input_mimo_all(ic, m);
967 		m = NULL;
968 	}
969 
970 	/*
971 	 * At this point we have passed the frame up the stack; thus
972 	 * the mbuf is no longer ours.
973 	 */
974 
975 	/*
976 	 * Track rx rssi and do any rx antenna management.
977 	 */
978 	ATH_RSSI_LPF(sc->sc_halstats.ns_avgrssi, rs->rs_rssi);
979 	if (sc->sc_diversity) {
980 		/*
981 		 * When using fast diversity, change the default rx
982 		 * antenna if diversity chooses the other antenna 3
983 		 * times in a row.
984 		 */
985 		if (sc->sc_defant != rs->rs_antenna) {
986 			if (++sc->sc_rxotherant >= 3)
987 				ath_setdefantenna(sc, rs->rs_antenna);
988 		} else
989 			sc->sc_rxotherant = 0;
990 	}
991 
992 	/* Handle slow diversity if enabled */
993 	if (sc->sc_dolnadiv) {
994 		ath_lna_rx_comb_scan(sc, rs, ticks, hz);
995 	}
996 
997 	if (sc->sc_softled) {
998 		/*
999 		 * Blink for any data frame.  Otherwise do a
1000 		 * heartbeat-style blink when idle.  The latter
1001 		 * is mainly for station mode where we depend on
1002 		 * periodic beacon frames to trigger the poll event.
1003 		 */
1004 		if (type == IEEE80211_FC0_TYPE_DATA) {
1005 			const HAL_RATE_TABLE *rt = sc->sc_currates;
1006 			ath_led_event(sc,
1007 			    rt->rateCodeToIndex[rs->rs_rate]);
1008 		} else if (ticks - sc->sc_ledevent >= sc->sc_ledidle)
1009 			ath_led_event(sc, 0);
1010 		}
1011 rx_next:
1012 	/*
1013 	 * Debugging - complain if we didn't NULL the mbuf pointer
1014 	 * here.
1015 	 */
1016 	if (m != NULL) {
1017 		device_printf(sc->sc_dev,
1018 		    "%s: mbuf %p should've been freed!\n",
1019 		    __func__,
1020 		    m);
1021 	}
1022 	return (is_good);
1023 }
1024 
1025 #define	ATH_RX_MAX		128
1026 
1027 /*
1028  * XXX TODO: break out the "get buffers" from "call ath_rx_pkt()" like
1029  * the EDMA code does.
1030  *
1031  * XXX TODO: then, do all of the RX list management stuff inside
1032  * ATH_RX_LOCK() so we don't end up potentially racing.  The EDMA
1033  * code is doing it right.
1034  */
1035 static void
1036 ath_rx_proc(struct ath_softc *sc, int resched)
1037 {
1038 #define	PA2DESC(_sc, _pa) \
1039 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
1040 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
1041 	struct ath_buf *bf;
1042 	struct ath_hal *ah = sc->sc_ah;
1043 #ifdef IEEE80211_SUPPORT_SUPERG
1044 	struct ieee80211com *ic = &sc->sc_ic;
1045 #endif
1046 	struct ath_desc *ds;
1047 	struct ath_rx_status *rs;
1048 	struct mbuf *m;
1049 	int ngood;
1050 	HAL_STATUS status;
1051 	int16_t nf;
1052 	u_int64_t tsf;
1053 	int npkts = 0;
1054 	int kickpcu = 0;
1055 	int ret;
1056 
1057 	/* XXX we must not hold the ATH_LOCK here */
1058 	ATH_UNLOCK_ASSERT(sc);
1059 	ATH_PCU_UNLOCK_ASSERT(sc);
1060 
1061 	ATH_PCU_LOCK(sc);
1062 	sc->sc_rxproc_cnt++;
1063 	kickpcu = sc->sc_kickpcu;
1064 	ATH_PCU_UNLOCK(sc);
1065 
1066 	ATH_LOCK(sc);
1067 	ath_power_set_power_state(sc, HAL_PM_AWAKE);
1068 	ATH_UNLOCK(sc);
1069 
1070 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: called\n", __func__);
1071 	ngood = 0;
1072 	nf = ath_hal_getchannoise(ah, sc->sc_curchan);
1073 	sc->sc_stats.ast_rx_noise = nf;
1074 	tsf = ath_hal_gettsf64(ah);
1075 	do {
1076 		/*
1077 		 * Don't process too many packets at a time; give the
1078 		 * TX thread time to also run - otherwise the TX
1079 		 * latency can jump by quite a bit, causing throughput
1080 		 * degredation.
1081 		 */
1082 		if (!kickpcu && npkts >= ATH_RX_MAX)
1083 			break;
1084 
1085 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1086 		if (sc->sc_rxslink && bf == NULL) {	/* NB: shouldn't happen */
1087 			device_printf(sc->sc_dev, "%s: no buffer!\n", __func__);
1088 			break;
1089 		} else if (bf == NULL) {
1090 			/*
1091 			 * End of List:
1092 			 * this can happen for non-self-linked RX chains
1093 			 */
1094 			sc->sc_stats.ast_rx_hitqueueend++;
1095 			break;
1096 		}
1097 		m = bf->bf_m;
1098 		if (m == NULL) {		/* NB: shouldn't happen */
1099 			/*
1100 			 * If mbuf allocation failed previously there
1101 			 * will be no mbuf; try again to re-populate it.
1102 			 */
1103 			/* XXX make debug msg */
1104 			device_printf(sc->sc_dev, "%s: no mbuf!\n", __func__);
1105 			TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1106 			goto rx_proc_next;
1107 		}
1108 		ds = bf->bf_desc;
1109 		if (ds->ds_link == bf->bf_daddr) {
1110 			/* NB: never process the self-linked entry at the end */
1111 			sc->sc_stats.ast_rx_hitqueueend++;
1112 			break;
1113 		}
1114 		/* XXX sync descriptor memory */
1115 		/*
1116 		 * Must provide the virtual address of the current
1117 		 * descriptor, the physical address, and the virtual
1118 		 * address of the next descriptor in the h/w chain.
1119 		 * This allows the HAL to look ahead to see if the
1120 		 * hardware is done with a descriptor by checking the
1121 		 * done bit in the following descriptor and the address
1122 		 * of the current descriptor the DMA engine is working
1123 		 * on.  All this is necessary because of our use of
1124 		 * a self-linked list to avoid rx overruns.
1125 		 */
1126 		rs = &bf->bf_status.ds_rxstat;
1127 		status = ath_hal_rxprocdesc(ah, ds,
1128 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1129 #ifdef ATH_DEBUG
1130 		if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
1131 			ath_printrxbuf(sc, bf, 0, status == HAL_OK);
1132 #endif
1133 
1134 #ifdef	ATH_DEBUG_ALQ
1135 		if (if_ath_alq_checkdebug(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS))
1136 		    if_ath_alq_post(&sc->sc_alq, ATH_ALQ_EDMA_RXSTATUS,
1137 		    sc->sc_rx_statuslen, (char *) ds);
1138 #endif	/* ATH_DEBUG_ALQ */
1139 
1140 		if (status == HAL_EINPROGRESS)
1141 			break;
1142 
1143 		TAILQ_REMOVE(&sc->sc_rxbuf, bf, bf_list);
1144 		npkts++;
1145 
1146 		/*
1147 		 * Process a single frame.
1148 		 */
1149 		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_POSTREAD);
1150 		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
1151 		bf->bf_m = NULL;
1152 		if (ath_rx_pkt(sc, rs, status, tsf, nf, HAL_RX_QUEUE_HP, bf, m))
1153 			ngood++;
1154 rx_proc_next:
1155 		/*
1156 		 * If there's a holding buffer, insert that onto
1157 		 * the RX list; the hardware is now definitely not pointing
1158 		 * to it now.
1159 		 */
1160 		ret = 0;
1161 		if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf != NULL) {
1162 			TAILQ_INSERT_TAIL(&sc->sc_rxbuf,
1163 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf,
1164 			    bf_list);
1165 			ret = ath_rxbuf_init(sc,
1166 			    sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf);
1167 		}
1168 		/*
1169 		 * Next, throw our buffer into the holding entry.  The hardware
1170 		 * may use the descriptor to read the link pointer before
1171 		 * DMAing the next descriptor in to write out a packet.
1172 		 */
1173 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = bf;
1174 	} while (ret == 0);
1175 
1176 	/* rx signal state monitoring */
1177 	ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
1178 	if (ngood)
1179 		sc->sc_lastrx = tsf;
1180 
1181 	ATH_KTR(sc, ATH_KTR_RXPROC, 2, "ath_rx_proc: npkts=%d, ngood=%d", npkts, ngood);
1182 	/* Queue DFS tasklet if needed */
1183 	if (resched && ath_dfs_tasklet_needed(sc, sc->sc_curchan))
1184 		taskqueue_enqueue(sc->sc_tq, &sc->sc_dfstask);
1185 
1186 	/*
1187 	 * Now that all the RX frames were handled that
1188 	 * need to be handled, kick the PCU if there's
1189 	 * been an RXEOL condition.
1190 	 */
1191 	if (resched && kickpcu) {
1192 		ATH_PCU_LOCK(sc);
1193 		ATH_KTR(sc, ATH_KTR_ERROR, 0, "ath_rx_proc: kickpcu");
1194 		device_printf(sc->sc_dev, "%s: kickpcu; handled %d packets\n",
1195 		    __func__, npkts);
1196 
1197 		/*
1198 		 * Go through the process of fully tearing down
1199 		 * the RX buffers and reinitialising them.
1200 		 *
1201 		 * There's a hardware bug that causes the RX FIFO
1202 		 * to get confused under certain conditions and
1203 		 * constantly write over the same frame, leading
1204 		 * the RX driver code here to get heavily confused.
1205 		 */
1206 		/*
1207 		 * XXX Has RX DMA stopped enough here to just call
1208 		 *     ath_startrecv()?
1209 		 * XXX Do we need to use the holding buffer to restart
1210 		 *     RX DMA by appending entries to the final
1211 		 *     descriptor?  Quite likely.
1212 		 */
1213 #if 1
1214 		ath_startrecv(sc);
1215 #else
1216 		/*
1217 		 * Disabled for now - it'd be nice to be able to do
1218 		 * this in order to limit the amount of CPU time spent
1219 		 * reinitialising the RX side (and thus minimise RX
1220 		 * drops) however there's a hardware issue that
1221 		 * causes things to get too far out of whack.
1222 		 */
1223 		/*
1224 		 * XXX can we hold the PCU lock here?
1225 		 * Are there any net80211 buffer calls involved?
1226 		 */
1227 		bf = TAILQ_FIRST(&sc->sc_rxbuf);
1228 		ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1229 		ath_hal_rxena(ah);		/* enable recv descriptors */
1230 		ath_mode_init(sc);		/* set filters, etc. */
1231 		ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
1232 #endif
1233 
1234 		ath_hal_intrset(ah, sc->sc_imask);
1235 		sc->sc_kickpcu = 0;
1236 		ATH_PCU_UNLOCK(sc);
1237 	}
1238 
1239 #ifdef IEEE80211_SUPPORT_SUPERG
1240 	if (resched)
1241 		ieee80211_ff_age_all(ic, 100);
1242 #endif
1243 
1244 	/*
1245 	 * Put the hardware to sleep again if we're done with it.
1246 	 */
1247 	ATH_LOCK(sc);
1248 	ath_power_restore_power_state(sc);
1249 	ATH_UNLOCK(sc);
1250 
1251 	/*
1252 	 * If we hit the maximum number of frames in this round,
1253 	 * reschedule for another immediate pass.  This gives
1254 	 * the TX and TX completion routines time to run, which
1255 	 * will reduce latency.
1256 	 */
1257 	if (npkts >= ATH_RX_MAX)
1258 		sc->sc_rx.recv_sched(sc, resched);
1259 
1260 	ATH_PCU_LOCK(sc);
1261 	sc->sc_rxproc_cnt--;
1262 	ATH_PCU_UNLOCK(sc);
1263 }
1264 #undef	PA2DESC
1265 #undef	ATH_RX_MAX
1266 
1267 /*
1268  * Only run the RX proc if it's not already running.
1269  * Since this may get run as part of the reset/flush path,
1270  * the task can't clash with an existing, running tasklet.
1271  */
1272 static void
1273 ath_legacy_rx_tasklet(void *arg, int npending)
1274 {
1275 	struct ath_softc *sc = arg;
1276 
1277 	ATH_KTR(sc, ATH_KTR_RXPROC, 1, "ath_rx_proc: pending=%d", npending);
1278 	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: pending %u\n", __func__, npending);
1279 	ATH_PCU_LOCK(sc);
1280 	if (sc->sc_inreset_cnt > 0) {
1281 		device_printf(sc->sc_dev,
1282 		    "%s: sc_inreset_cnt > 0; skipping\n", __func__);
1283 		ATH_PCU_UNLOCK(sc);
1284 		return;
1285 	}
1286 	ATH_PCU_UNLOCK(sc);
1287 
1288 	ath_rx_proc(sc, 1);
1289 }
1290 
1291 static void
1292 ath_legacy_flushrecv(struct ath_softc *sc)
1293 {
1294 
1295 	ath_rx_proc(sc, 0);
1296 }
1297 
1298 static void
1299 ath_legacy_flush_rxpending(struct ath_softc *sc)
1300 {
1301 
1302 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1303 
1304 	if (sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending != NULL) {
1305 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending);
1306 		sc->sc_rxedma[HAL_RX_QUEUE_LP].m_rxpending = NULL;
1307 	}
1308 	if (sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending != NULL) {
1309 		m_freem(sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending);
1310 		sc->sc_rxedma[HAL_RX_QUEUE_HP].m_rxpending = NULL;
1311 	}
1312 }
1313 
1314 static int
1315 ath_legacy_flush_rxholdbf(struct ath_softc *sc)
1316 {
1317 	struct ath_buf *bf;
1318 
1319 	/* XXX ATH_RX_LOCK_ASSERT(sc); */
1320 	/*
1321 	 * If there are RX holding buffers, free them here and return
1322 	 * them to the list.
1323 	 *
1324 	 * XXX should just verify that bf->bf_m is NULL, as it must
1325 	 * be at this point!
1326 	 */
1327 	bf = sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf;
1328 	if (bf != NULL) {
1329 		if (bf->bf_m != NULL)
1330 			m_freem(bf->bf_m);
1331 		bf->bf_m = NULL;
1332 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1333 		(void) ath_rxbuf_init(sc, bf);
1334 	}
1335 	sc->sc_rxedma[HAL_RX_QUEUE_HP].m_holdbf = NULL;
1336 
1337 	bf = sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf;
1338 	if (bf != NULL) {
1339 		if (bf->bf_m != NULL)
1340 			m_freem(bf->bf_m);
1341 		bf->bf_m = NULL;
1342 		TAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
1343 		(void) ath_rxbuf_init(sc, bf);
1344 	}
1345 	sc->sc_rxedma[HAL_RX_QUEUE_LP].m_holdbf = NULL;
1346 
1347 	return (0);
1348 }
1349 
1350 /*
1351  * Disable the receive h/w in preparation for a reset.
1352  */
1353 static void
1354 ath_legacy_stoprecv(struct ath_softc *sc, int dodelay)
1355 {
1356 #define	PA2DESC(_sc, _pa) \
1357 	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
1358 		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
1359 	struct ath_hal *ah = sc->sc_ah;
1360 
1361 	ATH_RX_LOCK(sc);
1362 
1363 	ath_hal_stoppcurecv(ah);	/* disable PCU */
1364 	ath_hal_setrxfilter(ah, 0);	/* clear recv filter */
1365 	ath_hal_stopdmarecv(ah);	/* disable DMA engine */
1366 	/*
1367 	 * TODO: see if this particular DELAY() is required; it may be
1368 	 * masking some missing FIFO flush or DMA sync.
1369 	 */
1370 #if 0
1371 	if (dodelay)
1372 #endif
1373 		DELAY(3000);		/* 3ms is long enough for 1 frame */
1374 #ifdef ATH_DEBUG
1375 	if (sc->sc_debug & (ATH_DEBUG_RESET | ATH_DEBUG_FATAL)) {
1376 		struct ath_buf *bf;
1377 		u_int ix;
1378 
1379 		device_printf(sc->sc_dev,
1380 		    "%s: rx queue %p, link %p\n",
1381 		    __func__,
1382 		    (caddr_t)(uintptr_t) ath_hal_getrxbuf(ah, HAL_RX_QUEUE_HP),
1383 		    sc->sc_rxlink);
1384 		ix = 0;
1385 		TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1386 			struct ath_desc *ds = bf->bf_desc;
1387 			struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
1388 			HAL_STATUS status = ath_hal_rxprocdesc(ah, ds,
1389 				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
1390 			if (status == HAL_OK || (sc->sc_debug & ATH_DEBUG_FATAL))
1391 				ath_printrxbuf(sc, bf, ix, status == HAL_OK);
1392 			ix++;
1393 		}
1394 	}
1395 #endif
1396 
1397 	(void) ath_legacy_flush_rxpending(sc);
1398 	(void) ath_legacy_flush_rxholdbf(sc);
1399 
1400 	sc->sc_rxlink = NULL;		/* just in case */
1401 
1402 	ATH_RX_UNLOCK(sc);
1403 #undef PA2DESC
1404 }
1405 
1406 /*
1407  * XXX TODO: something was calling startrecv without calling
1408  * stoprecv.  Let's figure out what/why.  It was showing up
1409  * as a mbuf leak (rxpending) and ath_buf leak (holdbf.)
1410  */
1411 
1412 /*
1413  * Enable the receive h/w following a reset.
1414  */
1415 static int
1416 ath_legacy_startrecv(struct ath_softc *sc)
1417 {
1418 	struct ath_hal *ah = sc->sc_ah;
1419 	struct ath_buf *bf;
1420 
1421 	ATH_RX_LOCK(sc);
1422 
1423 	/*
1424 	 * XXX should verify these are already all NULL!
1425 	 */
1426 	sc->sc_rxlink = NULL;
1427 	(void) ath_legacy_flush_rxpending(sc);
1428 	(void) ath_legacy_flush_rxholdbf(sc);
1429 
1430 	/*
1431 	 * Re-chain all of the buffers in the RX buffer list.
1432 	 */
1433 	TAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
1434 		int error = ath_rxbuf_init(sc, bf);
1435 		if (error != 0) {
1436 			DPRINTF(sc, ATH_DEBUG_RECV,
1437 				"%s: ath_rxbuf_init failed %d\n",
1438 				__func__, error);
1439 			return error;
1440 		}
1441 	}
1442 
1443 	bf = TAILQ_FIRST(&sc->sc_rxbuf);
1444 	ath_hal_putrxbuf(ah, bf->bf_daddr, HAL_RX_QUEUE_HP);
1445 	ath_hal_rxena(ah);		/* enable recv descriptors */
1446 	ath_mode_init(sc);		/* set filters, etc. */
1447 	ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
1448 
1449 	ATH_RX_UNLOCK(sc);
1450 	return 0;
1451 }
1452 
1453 static int
1454 ath_legacy_dma_rxsetup(struct ath_softc *sc)
1455 {
1456 	int error;
1457 
1458 	error = ath_descdma_setup(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
1459 	    "rx", sizeof(struct ath_desc), ath_rxbuf, 1);
1460 	if (error != 0)
1461 		return (error);
1462 
1463 	return (0);
1464 }
1465 
1466 static int
1467 ath_legacy_dma_rxteardown(struct ath_softc *sc)
1468 {
1469 
1470 	if (sc->sc_rxdma.dd_desc_len != 0)
1471 		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
1472 	return (0);
1473 }
1474 
1475 static void
1476 ath_legacy_recv_sched(struct ath_softc *sc, int dosched)
1477 {
1478 
1479 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1480 }
1481 
1482 static void
1483 ath_legacy_recv_sched_queue(struct ath_softc *sc, HAL_RX_QUEUE q,
1484     int dosched)
1485 {
1486 
1487 	taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
1488 }
1489 
1490 void
1491 ath_recv_setup_legacy(struct ath_softc *sc)
1492 {
1493 
1494 	/* Sensible legacy defaults */
1495 	/*
1496 	 * XXX this should be changed to properly support the
1497 	 * exact RX descriptor size for each HAL.
1498 	 */
1499 	sc->sc_rx_statuslen = sizeof(struct ath_desc);
1500 
1501 	sc->sc_rx.recv_start = ath_legacy_startrecv;
1502 	sc->sc_rx.recv_stop = ath_legacy_stoprecv;
1503 	sc->sc_rx.recv_flush = ath_legacy_flushrecv;
1504 	sc->sc_rx.recv_tasklet = ath_legacy_rx_tasklet;
1505 	sc->sc_rx.recv_rxbuf_init = ath_legacy_rxbuf_init;
1506 
1507 	sc->sc_rx.recv_setup = ath_legacy_dma_rxsetup;
1508 	sc->sc_rx.recv_teardown = ath_legacy_dma_rxteardown;
1509 	sc->sc_rx.recv_sched = ath_legacy_recv_sched;
1510 	sc->sc_rx.recv_sched_queue = ath_legacy_recv_sched_queue;
1511 }
1512