Index: if_bwn.c
===================================================================
--- if_bwn.c	(revision 204657)
+++ if_bwn.c	(working copy)
@@ -73,6 +73,7 @@
 #include <dev/bwn/if_bwnreg.h>
 #include <dev/bwn/if_bwnvar.h>
 
+#define	BWN_DEBUG
 SYSCTL_NODE(_hw, OID_AUTO, bwn, CTLFLAG_RD, 0, "Broadcom driver parameters");
 
 /*
@@ -102,6 +103,7 @@
 	BWN_DEBUG_FW		= 0x00004000,	/* firmware */
 	BWN_DEBUG_WME		= 0x00008000,	/* WME */
 	BWN_DEBUG_RF		= 0x00010000,	/* RF */
+	BWN_DEBUG_PIO		= 0x00020000,	/* PIO */
 	BWN_DEBUG_FATAL		= 0x80000000,	/* fatal errors */
 	BWN_DEBUG_ANY		= 0xffffffff
 };
@@ -124,7 +126,7 @@
     "uses H/W power control");
 static int	bwn_msi_disable = 0;		/* MSI disabled  */
 TUNABLE_INT("hw.bwn.msi_disable", &bwn_msi_disable);
-static int	bwn_usedma = 1;
+static int	bwn_usedma = 0;
 SYSCTL_INT(_hw_bwn, OID_AUTO, usedma, CTLFLAG_RD, &bwn_usedma, 0,
     "uses DMA");
 TUNABLE_INT("hw.bwn.usedma", &bwn_usedma);
@@ -936,8 +938,11 @@
 	sc->sc_sd = sd;
 #ifdef BWN_DEBUG
 	sc->sc_debug = bwn_debug;
+	sc->sc_debug |= BWN_DEBUG_ANY;
 #endif
 
+	device_printf(dev, "DEBUG %#x\n", sc->sc_debug);
+
 	if ((sc->sc_flags & BWN_FLAG_ATTACHED) == 0) {
 		error = bwn_attach_pre(sc);
 		if (error != 0)
@@ -1410,6 +1415,7 @@
 	struct bwn_pio_txqueue *tq = bwn_pio_select(mac, M_WME_GETAC(m));
 	struct bwn_softc *sc = mac->mac_sc;
 	struct bwn_txhdr txhdr;
+	struct ieee80211_frame *wh;
 	struct mbuf *m_new;
 	uint32_t ctl32;
 	int error;
@@ -1434,6 +1440,12 @@
 	tq->tq_used += roundup(m->m_pkthdr.len + BWN_HDRSIZE(mac), 4);
 	tq->tq_free--;
 
+	wh = mtod(m, struct ieee80211_frame *);
+	DPRINTF(sc, BWN_DEBUG_PIO,
+	    "tx: used %d free %d (type %#x subtype %#x)\n", tq->tq_used,
+	    tq->tq_free, wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK,
+	    wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK);
+
 	if (mac->mac_sd->sd_id.sd_rev >= 8) {
 		/*
 		 * XXX please removes m_defrag(9)
@@ -9236,6 +9248,8 @@
 	m->m_pkthdr.rcvif = ifp;
 	m->m_len = m->m_pkthdr.len = len + padding;
 
+	DPRINTF(sc, BWN_DEBUG_PIO, "rx: m %p len %d\n", m, m->m_pkthdr.len);
+
 	bwn_rxeof(prq->prq_mac, m, &rxhdr);
 
 	return (1);
@@ -9562,6 +9576,9 @@
 	tp->tp_m = NULL;
 	TAILQ_INSERT_TAIL(&tq->tq_pktlist, tp, tp_list);
 
+	DPRINTF(sc, BWN_DEBUG_PIO, "txeof: used %d free %d\n", tq->tq_used,
+	    tq->tq_free);
+
 	ifp->if_opackets++;
 
 	sc->sc_watchdog_timer = 0;