1 files changed, 813 insertions, 0 deletions

diff --git a/src/VBox/Devices/PC/ipxe/src/drivers/net/ath/ath9k/ath9k_xmit.c b/src/VBox/Devices/PC/ipxe/src/drivers/net/ath/ath9k/ath9k_xmit.c
new file mode 100644
index 00000000..7f4f28ab
--- /dev/null
+++ b/src/VBox/Devices/PC/ipxe/src/drivers/net/ath/ath9k/ath9k_xmit.c
@@ -0,0 +1,813 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ *
+ * Modified for iPXE by Scott K Logan <logans@cottsay.net> July 2011
+ * Original from Linux kernel 3.0.1
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <ipxe/io.h>
+
+#include "ath9k.h"
+#include "ar9003_mac.h"
+
+#define BITS_PER_BYTE           8
+#define OFDM_PLCP_BITS          22
+#define HT_RC_2_STREAMS(_rc)    ((((_rc) & 0x78) >> 3) + 1)
+#define L_STF                   8
+#define L_LTF                   8
+#define L_SIG                   4
+#define HT_SIG                  8
+#define HT_STF                  4
+#define HT_LTF(_ns)             (4 * (_ns))
+#define SYMBOL_TIME(_ns)        ((_ns) << 2) /* ns * 4 us */
+#define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5)  /* ns * 3.6 us */
+#define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
+#define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
+
+
+#define IS_HT_RATE(_rate)     ((_rate) & 0x80)
+
+static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
+			       struct ath_atx_tid *tid,
+			       struct list_head *bf_head);
+static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
+				struct ath_txq *txq, struct list_head *bf_q,
+				struct ath_tx_status *ts, int txok, int sendbar);
+static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
+			     struct list_head *head);
+static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len);
+
+enum {
+	MCS_HT20,
+	MCS_HT20_SGI,
+	MCS_HT40,
+	MCS_HT40_SGI,
+};
+
+/*********************/
+/* Aggregation logic */
+/*********************/
+
+static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid)
+{
+	struct ath_atx_ac *ac = tid->ac;
+
+	if (tid->paused)
+		return;
+
+	if (tid->sched)
+		return;
+
+	tid->sched = 1;
+	list_add_tail(&tid->list, &ac->tid_q);
+
+	if (ac->sched)
+		return;
+
+	ac->sched = 1;
+	list_add_tail(&ac->list, &txq->axq_acq);
+}
+
+static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
+{
+	struct ath_buf *bf = NULL;
+
+	if (list_empty(&sc->tx.txbuf)) {
+		return NULL;
+	}
+
+	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
+	list_del(&bf->list);
+
+	return bf;
+}
+
+static void ath_tx_return_buffer(struct ath_softc *sc, struct ath_buf *bf)
+{
+	list_add_tail(&bf->list, &sc->tx.txbuf);
+}
+
+/********************/
+/* Queue Management */
+/********************/
+
+struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath9k_tx_queue_info qi;
+	static const int subtype_txq_to_hwq[] = {
+		[WME_AC_BE] = ATH_TXQ_AC_BE,
+	};
+	int axq_qnum, i;
+
+	memset(&qi, 0, sizeof(qi));
+	qi.tqi_subtype = subtype_txq_to_hwq[subtype];
+	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
+	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
+	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
+	qi.tqi_physCompBuf = 0;
+
+	/*
+	 * Enable interrupts only for EOL and DESC conditions.
+	 * We mark tx descriptors to receive a DESC interrupt
+	 * when a tx queue gets deep; otherwise waiting for the
+	 * EOL to reap descriptors.  Note that this is done to
+	 * reduce interrupt load and this only defers reaping
+	 * descriptors, never transmitting frames.  Aside from
+	 * reducing interrupts this also permits more concurrency.
+	 * The only potential downside is if the tx queue backs
+	 * up in which case the top half of the kernel may backup
+	 * due to a lack of tx descriptors.
+	 *
+	 * The UAPSD queue is an exception, since we take a desc-
+	 * based intr on the EOSP frames.
+	 */
+	qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
+			TXQ_FLAG_TXDESCINT_ENABLE;
+
+	axq_qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
+	if (axq_qnum == -1) {
+		/*
+		 * NB: don't print a message, this happens
+		 * normally on parts with too few tx queues
+		 */
+		return NULL;
+	}
+	if ((unsigned int)axq_qnum >= ARRAY_SIZE(sc->tx.txq)) {
+		DBG("ath9k: qnum %d out of range, max %zd!\n",
+			axq_qnum, ARRAY_SIZE(sc->tx.txq));
+		ath9k_hw_releasetxqueue(ah, axq_qnum);
+		return NULL;
+	}
+	if (!ATH_TXQ_SETUP(sc, axq_qnum)) {
+		struct ath_txq *txq = &sc->tx.txq[axq_qnum];
+
+		txq->axq_qnum = axq_qnum;
+		txq->mac80211_qnum = -1;
+		txq->axq_link = NULL;
+		INIT_LIST_HEAD(&txq->axq_q);
+		INIT_LIST_HEAD(&txq->axq_acq);
+		txq->axq_depth = 0;
+		txq->axq_ampdu_depth = 0;
+		txq->axq_tx_inprogress = 0;
+		sc->tx.txqsetup |= 1<<axq_qnum;
+
+		txq->txq_headidx = txq->txq_tailidx = 0;
+		for (i = 0; i < ATH_TXFIFO_DEPTH; i++)
+			INIT_LIST_HEAD(&txq->txq_fifo[i]);
+		INIT_LIST_HEAD(&txq->txq_fifo_pending);
+	}
+	return &sc->tx.txq[axq_qnum];
+}
+
+/*
+ * Drain a given TX queue (could be Beacon or Data)
+ *
+ * This assumes output has been stopped and
+ * we do not need to block ath_tx_tasklet.
+ */
+void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, int retry_tx __unused)
+{
+	struct ath_buf *bf, *lastbf __unused;
+	struct list_head bf_head;
+	struct ath_tx_status ts;
+
+	memset(&ts, 0, sizeof(ts));
+	INIT_LIST_HEAD(&bf_head);
+
+	for (;;) {
+		if (list_empty(&txq->axq_q)) {
+			txq->axq_link = NULL;
+			break;
+		}
+		bf = list_first_entry(&txq->axq_q, struct ath_buf,
+				      list);
+
+		if (bf->bf_stale) {
+			list_del(&bf->list);
+
+			ath_tx_return_buffer(sc, bf);
+			continue;
+		}
+
+		lastbf = bf->bf_lastbf;
+
+		list_cut_position(&bf_head, &txq->axq_q, &lastbf->list);
+
+		txq->axq_depth--;
+		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
+	}
+
+	txq->axq_tx_inprogress = 0;
+}
+
+int ath_drain_all_txq(struct ath_softc *sc, int retry_tx)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_txq *txq;
+	int i, npend = 0;
+
+	if (sc->sc_flags & SC_OP_INVALID)
+		return 1;
+
+	ath9k_hw_abort_tx_dma(ah);
+
+	/* Check if any queue remains active */
+	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
+		if (!ATH_TXQ_SETUP(sc, i))
+			continue;
+
+		npend += ath9k_hw_numtxpending(ah, sc->tx.txq[i].axq_qnum);
+	}
+
+	if (npend)
+		DBG("ath9k: Failed to stop TX DMA!\n");
+
+	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
+		if (!ATH_TXQ_SETUP(sc, i))
+			continue;
+
+		/*
+		 * The caller will resume queues with ieee80211_wake_queues.
+		 * Mark the queue as not stopped to prevent ath_tx_complete
+		 * from waking the queue too early.
+		 */
+		txq = &sc->tx.txq[i];
+		txq->stopped = 0;
+		ath_draintxq(sc, txq, retry_tx);
+	}
+
+	return !npend;
+}
+
+void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
+{
+	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
+	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
+}
+
+/* For each axq_acq entry, for each tid, try to schedule packets
+ * for transmit until ampdu_depth has reached min Q depth.
+ */
+void ath_txq_schedule(struct ath_softc *sc __unused, struct ath_txq *txq)
+{
+	struct ath_atx_ac *ac, *ac_tmp, *last_ac;
+	struct ath_atx_tid *tid, *last_tid;
+
+	if (list_empty(&txq->axq_acq) ||
+	    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
+		return;
+
+	ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
+	last_ac = list_entry(txq->axq_acq.prev, struct ath_atx_ac, list);
+
+	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
+		last_tid = list_entry(ac->tid_q.prev, struct ath_atx_tid, list);
+		list_del(&ac->list);
+		ac->sched = 0;
+
+		while (!list_empty(&ac->tid_q)) {
+			tid = list_first_entry(&ac->tid_q, struct ath_atx_tid,
+					       list);
+			list_del(&tid->list);
+			tid->sched = 0;
+
+			if (tid->paused)
+				continue;
+
+			/*
+			 * add tid to round-robin queue if more frames
+			 * are pending for the tid
+			 */
+			if (!list_empty(&tid->buf_q))
+				ath_tx_queue_tid(txq, tid);
+
+			if (tid == last_tid ||
+			    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
+				break;
+		}
+
+		if (!list_empty(&ac->tid_q)) {
+			if (!ac->sched) {
+				ac->sched = 1;
+				list_add_tail(&ac->list, &txq->axq_acq);
+			}
+		}
+
+		if (ac == last_ac ||
+		    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
+			return;
+	}
+}
+
+/***********/
+/* TX, DMA */
+/***********/
+
+/*
+ * Insert a chain of ath_buf (descriptors) on a txq and
+ * assume the descriptors are already chained together by caller.
+ */
+static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
+			     struct list_head *head)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_buf *bf;
+
+	/*
+	 * Insert the frame on the outbound list and
+	 * pass it on to the hardware.
+	 */
+
+	if (list_empty(head))
+		return;
+
+	bf = list_first_entry(head, struct ath_buf, list);
+
+	DBGIO("ath9k: "
+		"qnum: %d, txq depth: %d\n", txq->axq_qnum, txq->axq_depth);
+
+	list_splice_tail_init(head, &txq->axq_q);
+
+	if (txq->axq_link == NULL) {
+		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
+		DBGIO("ath9k: TXDP[%d] = %llx (%p)\n",
+			txq->axq_qnum, ito64(bf->bf_daddr),
+			bf->bf_desc);
+	} else {
+		*txq->axq_link = bf->bf_daddr;
+		DBGIO("ath9k: "
+			"link[%d] (%p)=%llx (%p)\n",
+			txq->axq_qnum, txq->axq_link,
+			ito64(bf->bf_daddr), bf->bf_desc);
+	}
+	ath9k_hw_get_desc_link(ah, bf->bf_lastbf->bf_desc,
+			       &txq->axq_link);
+	ath9k_hw_txstart(ah, txq->axq_qnum);
+
+	txq->axq_depth++;
+}
+
+static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
+			       struct ath_atx_tid *tid,
+			       struct list_head *bf_head)
+{
+	struct ath_buf *bf;
+
+	bf = list_first_entry(bf_head, struct ath_buf, list);
+	bf->bf_state.bf_type &= ~BUF_AMPDU;
+
+	/* update starting sequence number for subsequent ADDBA request */
+	if (tid)
+		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
+
+	bf->bf_lastbf = bf;
+	ath_buf_set_rate(sc, bf, iob_len(bf->bf_mpdu) + FCS_LEN);
+	ath_tx_txqaddbuf(sc, txq, bf_head);
+}
+
+static enum ath9k_pkt_type get_hw_packet_type(struct io_buffer *iob)
+{
+	struct ieee80211_frame *hdr;
+	enum ath9k_pkt_type htype;
+	u16 fc;
+
+	hdr = (struct ieee80211_frame *)iob->data;
+	fc = hdr->fc;
+
+	if ((fc & (IEEE80211_FC_TYPE | IEEE80211_FC_SUBTYPE)) == (IEEE80211_TYPE_MGMT | IEEE80211_STYPE_BEACON))
+		htype = ATH9K_PKT_TYPE_BEACON;
+	else if ((fc & (IEEE80211_FC_TYPE | IEEE80211_FC_SUBTYPE)) == (IEEE80211_TYPE_MGMT | IEEE80211_STYPE_PROBE_RESP))
+		htype = ATH9K_PKT_TYPE_PROBE_RESP;
+	else
+		htype = ATH9K_PKT_TYPE_NORMAL;
+
+	return htype;
+}
+
+static int setup_tx_flags(struct io_buffer *iob __unused)
+{
+	int flags = 0;
+
+	flags |= ATH9K_TXDESC_INTREQ;
+
+	return flags;
+}
+
+u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath9k_channel *curchan = ah->curchan;
+	if ((sc->sc_flags & SC_OP_ENABLE_APM) &&
+			(curchan->channelFlags & CHANNEL_5GHZ) &&
+			(chainmask == 0x7) && (rate < 0x90))
+		return 0x3;
+	else
+		return chainmask;
+}
+
+static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
+{
+	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	struct ath9k_11n_rate_series series[4];
+	const struct ath9k_legacy_rate *rate;
+	int i, flags = 0;
+	u8 rix = 0, ctsrate = 0;
+	int is_pspoll;
+
+	memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
+
+	is_pspoll = 0;
+
+	/*
+	 * We check if Short Preamble is needed for the CTS rate by
+	 * checking the BSS's global flag.
+	 * But for the rate series, IEEE80211_TX_RC_USE_SHORT_PREAMBLE is used.
+	 */
+	rate = &sc->rates[sc->hw_rix];
+	ctsrate = rate->hw_value;
+	if (sc->sc_flags & SC_OP_PREAMBLE_SHORT)
+		ctsrate |= rate->hw_value_short;
+
+	for (i = 0; i < 4; i++) {
+		int is_40 __unused, is_sgi __unused, is_sp;
+		int phy;
+
+		rix = sc->hw_rix;
+		series[i].Tries = ATH_TXMAXTRY;
+
+		if (sc->sc_flags & SC_OP_PROTECT_ENABLE) {
+			series[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
+			flags |= ATH9K_TXDESC_CTSENA;
+		}
+
+		is_sp = !!(rate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
+
+		/* legacy rates */
+		if ((sc->dev->channels + sc->dev->channel)->band == NET80211_BAND_2GHZ)
+			phy = CHANNEL_CCK;
+		else
+			phy = CHANNEL_OFDM;
+
+		series[i].Rate = rate->hw_value;
+		if (rate->hw_value_short && (sc->sc_flags & SC_OP_PREAMBLE_SHORT)) {
+			if (rate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
+				series[i].Rate |= rate->hw_value_short;
+		} else {
+			is_sp = 0;
+		}
+
+		if (bf->bf_state.bfs_paprd)
+			series[i].ChSel = common->tx_chainmask;
+		else
+			series[i].ChSel = ath_txchainmask_reduction(sc,
+					common->tx_chainmask, series[i].Rate);
+
+		series[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
+			phy, rate->bitrate * 100, len, rix, is_sp);
+	}
+
+	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
+	if (bf_isaggr(bf) && (len > sc->sc_ah->caps.rts_aggr_limit))
+		flags &= ~ATH9K_TXDESC_RTSENA;
+
+	/* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive. */
+	if (flags & ATH9K_TXDESC_RTSENA)
+		flags &= ~ATH9K_TXDESC_CTSENA;
+
+	/* set dur_update_en for l-sig computation except for PS-Poll frames */
+	ath9k_hw_set11n_ratescenario(sc->sc_ah, bf->bf_desc,
+				     bf->bf_lastbf->bf_desc,
+				     !is_pspoll, ctsrate,
+				     0, series, 4, flags);
+
+}
+
+static struct ath_buf *ath_tx_setup_buffer(struct net80211_device *dev,
+					   struct ath_txq *txq,
+					   struct io_buffer *iob)
+{
+	struct ath_softc *sc = dev->priv;
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_buf *bf;
+	struct ath_desc *ds;
+	int frm_type;
+	static const enum ath9k_key_type net80211_keytype_to_ath[] = {
+			[NET80211_CRYPT_NONE] = ATH9K_KEY_TYPE_CLEAR,
+			[NET80211_CRYPT_WEP] = ATH9K_KEY_TYPE_WEP,
+			[NET80211_CRYPT_TKIP] = ATH9K_KEY_TYPE_TKIP,
+			[NET80211_CRYPT_CCMP] = ATH9K_KEY_TYPE_AES,
+			[NET80211_CRYPT_UNKNOWN] = ATH9K_KEY_TYPE_CLEAR,
+	};
+
+	bf = ath_tx_get_buffer(sc);
+	if (!bf) {
+		DBG("ath9k: TX buffers are full\n");
+		return NULL;
+	}
+
+	ATH_TXBUF_RESET(bf);
+
+	bf->bf_flags = setup_tx_flags(iob);
+	bf->bf_mpdu = iob;
+
+	bf->bf_buf_addr = virt_to_bus(iob->data);
+
+	frm_type = get_hw_packet_type(iob);
+
+	ds = bf->bf_desc;
+	ath9k_hw_set_desc_link(ah, ds, 0);
+
+	ath9k_hw_set11n_txdesc(ah, ds, iob_len(iob) + FCS_LEN, frm_type, MAX_RATE_POWER,
+			       ATH9K_TXKEYIX_INVALID, net80211_keytype_to_ath[dev->crypto->algorithm], bf->bf_flags);
+
+	ath9k_hw_filltxdesc(ah, ds,
+			    iob_len(iob),	/* segment length */
+			    1,		/* first segment */
+			    1,		/* last segment */
+			    ds,		/* first descriptor */
+			    bf->bf_buf_addr,
+			    txq->axq_qnum);
+
+
+	return bf;
+}
+
+/* FIXME: tx power */
+static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf,
+			     struct ath_tx_control *txctl)
+{
+	struct list_head bf_head;
+	struct ath_atx_tid *tid = NULL;
+
+	INIT_LIST_HEAD(&bf_head);
+	list_add_tail(&bf->list, &bf_head);
+
+	bf->bf_state.bfs_paprd = txctl->paprd;
+
+	if (txctl->paprd)
+		bf->bf_state.bfs_paprd_timestamp = ( currticks() * 1000 ) / TICKS_PER_SEC;
+
+	ath9k_hw_set_clrdmask(sc->sc_ah, bf->bf_desc, 1);
+
+	ath_tx_send_normal(sc, txctl->txq, tid, &bf_head);
+}
+
+/* Upon failure caller should free iob */
+int ath_tx_start(struct net80211_device *dev, struct io_buffer *iob,
+		 struct ath_tx_control *txctl)
+{
+	struct ath_softc *sc = dev->priv;
+	struct ath_txq *txq = txctl->txq;
+	struct ath_buf *bf;
+	int q;
+
+	/*
+	 * At this point, the vif, hw_key and sta pointers in the tx control
+	 * info are no longer valid (overwritten by the ath_frame_info data.
+	 */
+
+	bf = ath_tx_setup_buffer(dev, txctl->txq, iob);
+	if (!bf)
+		return -ENOMEM;
+
+	q = 0;
+	if (txq == sc->tx.txq_map[q] &&
+	    ++txq->pending_frames > ATH_MAX_QDEPTH && !txq->stopped) {
+		txq->stopped = 1;
+	}
+
+	ath_tx_start_dma(sc, bf, txctl);
+
+	return 0;
+}
+
+/*****************/
+/* TX Completion */
+/*****************/
+
+static void ath_tx_complete(struct ath_softc *sc, struct io_buffer *iob,
+			    int tx_flags __unused, struct ath_tx_status *ts, struct ath_txq *txq)
+{
+	struct net80211_device *dev = sc->dev;
+	int q, padpos __unused, padsize __unused;
+
+	DBGIO("ath9k: TX complete: iob: %p\n", iob);
+
+	q = 0;
+	if (txq == sc->tx.txq_map[q]) {
+		if (--txq->pending_frames < 0)
+			txq->pending_frames = 0;
+
+		if (txq->stopped && txq->pending_frames < ATH_MAX_QDEPTH) {
+			txq->stopped = 0;
+		}
+	}
+
+	net80211_tx_complete(dev, iob, ts->ts_longretry,
+			(ts->ts_status & ATH9K_TXERR_MASK) ? EIO : 0);
+}
+
+static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
+				struct ath_txq *txq, struct list_head *bf_q,
+				struct ath_tx_status *ts, int txok, int sendbar)
+{
+	struct io_buffer *iob = bf->bf_mpdu;
+	int tx_flags = 0;
+
+	if (sendbar)
+		tx_flags = ATH_TX_BAR;
+
+	if (!txok) {
+		tx_flags |= ATH_TX_ERROR;
+
+		if (bf_isxretried(bf))
+			tx_flags |= ATH_TX_XRETRY;
+	}
+
+	bf->bf_buf_addr = 0;
+
+	ath_tx_complete(sc, iob, tx_flags,
+			ts, txq);
+
+	/* At this point, iob (bf->bf_mpdu) is consumed...make sure we don't
+	 * accidentally reference it later.
+	 */
+	bf->bf_mpdu = NULL;
+
+	/*
+	 * Return the list of ath_buf of this mpdu to free queue
+	 */
+	list_splice_tail_init(bf_q, &sc->tx.txbuf);
+}
+
+static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
+{
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_buf *bf, *lastbf, *bf_held = NULL;
+	struct list_head bf_head;
+	struct ath_desc *ds;
+	struct ath_tx_status ts;
+	int txok;
+	int status;
+
+	DBGIO("ath9k: tx queue %d (%x), link %p\n",
+		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
+		txq->axq_link);
+
+	for (;;) {
+		if (list_empty(&txq->axq_q)) {
+			txq->axq_link = NULL;
+			if (sc->sc_flags & SC_OP_TXAGGR)
+				ath_txq_schedule(sc, txq);
+			break;
+		}
+		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
+
+		/*
+		 * There is a race condition that a BH gets scheduled
+		 * after sw writes TxE and before hw re-load the last
+		 * descriptor to get the newly chained one.
+		 * Software must keep the last DONE descriptor as a
+		 * holding descriptor - software does so by marking
+		 * it with the STALE flag.
+		 */
+		bf_held = NULL;
+		if (bf->bf_stale) {
+			bf_held = bf;
+			if (list_is_last(&bf_held->list, &txq->axq_q)) {
+				break;
+			} else {
+				bf = list_entry(bf_held->list.next,
+						struct ath_buf, list);
+			}
+		}
+
+		lastbf = bf->bf_lastbf;
+		ds = lastbf->bf_desc;
+
+		memset(&ts, 0, sizeof(ts));
+		status = ath9k_hw_txprocdesc(ah, ds, &ts);
+		if (status == -EINPROGRESS) {
+			break;
+		}
+
+		/*
+		 * Remove ath_buf's of the same transmit unit from txq,
+		 * however leave the last descriptor back as the holding
+		 * descriptor for hw.
+		 */
+		lastbf->bf_stale = 1;
+		INIT_LIST_HEAD(&bf_head);
+		if (!list_is_singular(&lastbf->list))
+			list_cut_position(&bf_head,
+				&txq->axq_q, lastbf->list.prev);
+
+		txq->axq_depth--;
+		txok = !(ts.ts_status & ATH9K_TXERR_MASK);
+		txq->axq_tx_inprogress = 0;
+		if (bf_held)
+			list_del(&bf_held->list);
+
+		if (bf_held)
+			ath_tx_return_buffer(sc, bf_held);
+
+		/*
+		 * This frame is sent out as a single frame.
+		 * Use hardware retry status for this frame.
+		 */
+		if (ts.ts_status & ATH9K_TXERR_XRETRY)
+			bf->bf_state.bf_type |= BUF_XRETRY;
+
+		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, txok, 0);
+
+		if (sc->sc_flags & SC_OP_TXAGGR)
+			ath_txq_schedule(sc, txq);
+	}
+}
+
+static void ath_tx_complete_poll_work(struct ath_softc *sc)
+{
+	struct ath_txq *txq;
+	int i;
+	int needreset = 0;
+
+	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++)
+		if (ATH_TXQ_SETUP(sc, i)) {
+			txq = &sc->tx.txq[i];
+			if (txq->axq_depth) {
+				if (txq->axq_tx_inprogress) {
+					needreset = 1;
+					break;
+				} else {
+					txq->axq_tx_inprogress = 1;
+				}
+			}
+		}
+
+	if (needreset) {
+		DBG("ath9k: "
+			"tx hung, resetting the chip\n");
+		ath_reset(sc, 1);
+	}
+
+	sc->tx_complete_work_timer = ( currticks() * 1000 ) / TICKS_PER_SEC + ATH_TX_COMPLETE_POLL_INT;
+}
+
+
+
+void ath_tx_tasklet(struct ath_softc *sc)
+{
+	int i;
+	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1);
+
+	ath9k_hw_gettxintrtxqs(sc->sc_ah, &qcumask);
+
+	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
+		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
+			ath_tx_processq(sc, &sc->tx.txq[i]);
+	}
+}
+
+/*****************/
+/* Init, Cleanup */
+/*****************/
+
+int ath_tx_init(struct ath_softc *sc, int nbufs)
+{
+	int error = 0;
+
+	error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
+				  "tx", nbufs, 1, 1);
+	if (error != 0) {
+		DBG("ath9k: "
+			"Failed to allocate tx descriptors: %d\n", error);
+		goto err;
+	}
+
+	sc->tx_complete_work = ath_tx_complete_poll_work;
+
+err:
+	if (error != 0)
+		ath_tx_cleanup(sc);
+
+	return error;
+}
+
+void ath_tx_cleanup(struct ath_softc *sc)
+{
+	if (sc->tx.txdma.dd_desc_len != 0)
+		ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
+}