diff --git a/sys/dev/ath/if_ath.c b/sys/dev/ath/if_ath.c
index 698b8d1a2853..4bc5c31812e7 100644
--- a/sys/dev/ath/if_ath.c
+++ b/sys/dev/ath/if_ath.c
@@ -2450,13 +2450,15 @@ ath_bmiss_vap(struct ieee80211vap *vap)
 	ath_power_setpower(sc, HAL_PM_AWAKE, 0);
 	ath_power_restore_power_state(sc);
 	ATH_UNLOCK(sc);
+
 	DPRINTF(sc, ATH_DEBUG_BEACON,
 	    "%s: forced awake; force syncbeacon=1\n", __func__);
-
-	/*
-	 * Attempt to force a beacon resync.
-	 */
-	sc->sc_syncbeacon = 1;
+	if ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) == 0) {
+		/*
+		 * Attempt to force a beacon resync.
+		 */
+		sc->sc_syncbeacon = 1;
+	}
 
 	ATH_VAP(vap)->av_bmiss(vap);
 }
@@ -6061,19 +6063,25 @@ ath_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
 			 * In that case, we may not receive an actual
 			 * beacon to update the beacon timer and thus we
 			 * won't get notified of the missing beacons.
+			 *
+			 * Also, don't do any of this if we're not running
+			 * with hardware beacon support, as that'll interfere
+			 * with an AP VAP.
 			 */
 			if (ostate != IEEE80211_S_RUN &&
 			    ostate != IEEE80211_S_SLEEP) {
-				DPRINTF(sc, ATH_DEBUG_BEACON,
-				    "%s: STA; syncbeacon=1\n", __func__);
-				sc->sc_syncbeacon = 1;
+
+				if ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) == 0) {
+					DPRINTF(sc, ATH_DEBUG_BEACON,
+					    "%s: STA; syncbeacon=1\n", __func__);
+					sc->sc_syncbeacon = 1;
+					if (csa_run_transition)
+						ath_beacon_config(sc, vap);
+				}
 
 				/* Quiet time handling - ensure we resync */
 				memset(&avp->quiet_ie, 0, sizeof(avp->quiet_ie));
 
-				if (csa_run_transition)
-					ath_beacon_config(sc, vap);
-
 			/*
 			 * PR: kern/175227
 			 *
@@ -6086,7 +6094,9 @@ ath_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
 			 * timer fires (too often), leading to a STA
 			 * disassociation.
 			 */
-				sc->sc_beacons = 1;
+				if ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) == 0) {
+					sc->sc_beacons = 1;
+				}
 			}
 			break;
 		case IEEE80211_M_MONITOR:
diff --git a/sys/dev/ath/if_ath_beacon.c b/sys/dev/ath/if_ath_beacon.c
index ac1244c5f8e7..6da36a176319 100644
--- a/sys/dev/ath/if_ath_beacon.c
+++ b/sys/dev/ath/if_ath_beacon.c
@@ -448,9 +448,11 @@ ath_beacon_proc(void *arg, int pending)
 	 * many consecutive beacons reset the device.
 	 */
 	if (ath_hal_numtxpending(ah, sc->sc_bhalq) != 0) {
+
 		sc->sc_bmisscount++;
 		sc->sc_stats.ast_be_missed++;
 		ath_beacon_miss(sc);
+
 		DPRINTF(sc, ATH_DEBUG_BEACON,
 			"%s: missed %u consecutive beacons\n",
 			__func__, sc->sc_bmisscount);
@@ -935,15 +937,33 @@ ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
 	u_int32_t nexttbtt_u8, intval_u8;
 	u_int64_t tsf, tsf_beacon;
 
-	if (vap == NULL)
-		vap = TAILQ_FIRST(&ic->ic_vaps);	/* XXX */
 	/*
-	 * Just ensure that we aren't being called when the last
-	 * VAP is destroyed.
+	 * Find the first VAP that we /can/ use a beacon configuration for.
+	 * If it's a STA VAP then if it has SWBMISS set we should ignore it.
+	 *
+	 * Yes, ideally we'd not have a STA without SWBMISS followed by an
+	 * AP STA, and yes this isn't ready for P2P/TSF2 logic on AR9300 and
+	 * later chips.
 	 */
 	if (vap == NULL) {
-		device_printf(sc->sc_dev, "%s: called with no VAPs\n",
-		    __func__);
+		IEEE80211_LOCK(ic);
+		TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
+			/* A STA VAP w/ SWBMISS set can't be used for beaconing */
+			if ((vap->iv_opmode == IEEE80211_M_STA) &&
+			    ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) != 0))
+				continue;
+			break;
+		}
+		IEEE80211_UNLOCK(ic);
+	}
+
+	if (vap == NULL) {
+		device_printf(sc->sc_dev, "called with no valid vaps?\n");
+		return;
+	}
+
+	if ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) != 0) {
+		device_printf(sc->sc_dev, "called on VAP with SWBMISS set?\n");
 		return;
 	}
 
@@ -1004,8 +1024,7 @@ ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
 	else
 		nexttbtt = roundup(nexttbtt, intval);
 
-	DPRINTF(sc, ATH_DEBUG_BEACON, "%s: nexttbtt %u intval %u (%u)\n",
-		__func__, nexttbtt, intval, ni->ni_intval);
+
 	if (ic->ic_opmode == IEEE80211_M_STA && !sc->sc_swbmiss) {
 		HAL_BEACON_STATE bs;
 		int dtimperiod, dtimcount;
@@ -1196,8 +1215,8 @@ ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
 		 * nexttbtt and intval is TU/8.
 		 */
 		if (sc->sc_isedma) {
-			nexttbtt_u8 = (nexttbtt << 3);
-			intval_u8 = (intval << 3);
+			nexttbtt_u8 = (nexttbtt << 3) & HAL_BEACON_PERIOD_TU8;
+			intval_u8 = (intval << 3) & HAL_BEACON_PERIOD_TU8;
 			if (intval & HAL_BEACON_ENA)
 				intval_u8 |= HAL_BEACON_ENA;
 			if (intval & HAL_BEACON_RESET_TSF)
@@ -1216,6 +1235,15 @@ ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
 	}
 	ieee80211_free_node(ni);
 
+	tsf = ath_hal_gettsf64(ah);
+	DPRINTF(sc, ATH_DEBUG_BEACON,
+	    "%s: nexttbtt %u intval %u (%u), tsf64=%llu tsfbeacon=%llu delta=%lld\n",
+	    __func__, nexttbtt, intval, ni->ni_intval,
+	    (unsigned long long) tsf,
+	    (unsigned long long) tsf_beacon,
+	    (long long) tsf -
+	    (long long) tsf_beacon);
+
 	ATH_LOCK(sc);
 	ath_power_restore_power_state(sc);
 	ATH_UNLOCK(sc);
diff --git a/sys/dev/ath/if_ath_rx.c b/sys/dev/ath/if_ath_rx.c
index 58da21f09638..588194a942db 100644
--- a/sys/dev/ath/if_ath_rx.c
+++ b/sys/dev/ath/if_ath_rx.c
@@ -463,6 +463,7 @@ ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
 			    sc->sc_syncbeacon &&
 			    (!sc->sc_swbmiss) &&
 			    ni == vap->iv_bss &&
+			    ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) == 0) &&
 			    (vap->iv_state == IEEE80211_S_RUN || vap->iv_state == IEEE80211_S_SLEEP)) {
 				DPRINTF(sc, ATH_DEBUG_BEACON,
 				    "%s: syncbeacon=1; syncing\n",