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kernel-fxtec-pro1x/drivers/net/wireless/ath9k/xmit.c
Sujith 2660b81a37 ath9k: Remove all the useless ah_ variable prefixes 
Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-02-13 13:45:10 -05:00

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/*
* Copyright (c) 2008 Atheros Communications Inc.
*
* 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 "ath9k.h"
#define BITS_PER_BYTE 8
#define OFDM_PLCP_BITS 22
#define HT_RC_2_MCS(_rc) ((_rc) & 0x0f)
#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 OFDM_SIFS_TIME 16
static u32 bits_per_symbol[][2] = {
/* 20MHz 40MHz */
{ 26, 54 }, /* 0: BPSK */
{ 52, 108 }, /* 1: QPSK 1/2 */
{ 78, 162 }, /* 2: QPSK 3/4 */
{ 104, 216 }, /* 3: 16-QAM 1/2 */
{ 156, 324 }, /* 4: 16-QAM 3/4 */
{ 208, 432 }, /* 5: 64-QAM 2/3 */
{ 234, 486 }, /* 6: 64-QAM 3/4 */
{ 260, 540 }, /* 7: 64-QAM 5/6 */
{ 52, 108 }, /* 8: BPSK */
{ 104, 216 }, /* 9: QPSK 1/2 */
{ 156, 324 }, /* 10: QPSK 3/4 */
{ 208, 432 }, /* 11: 16-QAM 1/2 */
{ 312, 648 }, /* 12: 16-QAM 3/4 */
{ 416, 864 }, /* 13: 64-QAM 2/3 */
{ 468, 972 }, /* 14: 64-QAM 3/4 */
{ 520, 1080 }, /* 15: 64-QAM 5/6 */
};
#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 list_head *bf_q,
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);
/*********************/
/* Aggregation logic */
/*********************/
static int ath_aggr_query(struct ath_softc *sc, struct ath_node *an, u8 tidno)
{
struct ath_atx_tid *tid;
tid = ATH_AN_2_TID(an, tidno);
if (tid->state & AGGR_ADDBA_COMPLETE ||
tid->state & AGGR_ADDBA_PROGRESS)
return 1;
else
return 0;
}
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 = true;
list_add_tail(&tid->list, &ac->tid_q);
if (ac->sched)
return;
ac->sched = true;
list_add_tail(&ac->list, &txq->axq_acq);
}
static void ath_tx_pause_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
{
struct ath_txq *txq = &sc->tx.txq[tid->ac->qnum];
spin_lock_bh(&txq->axq_lock);
tid->paused++;
spin_unlock_bh(&txq->axq_lock);
}
static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
{
struct ath_txq *txq = &sc->tx.txq[tid->ac->qnum];
ASSERT(tid->paused > 0);
spin_lock_bh(&txq->axq_lock);
tid->paused--;
if (tid->paused > 0)
goto unlock;
if (list_empty(&tid->buf_q))
goto unlock;
ath_tx_queue_tid(txq, tid);
ath_txq_schedule(sc, txq);
unlock:
spin_unlock_bh(&txq->axq_lock);
}
static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
{
struct ath_txq *txq = &sc->tx.txq[tid->ac->qnum];
struct ath_buf *bf;
struct list_head bf_head;
INIT_LIST_HEAD(&bf_head);
ASSERT(tid->paused > 0);
spin_lock_bh(&txq->axq_lock);
tid->paused--;
if (tid->paused > 0) {
spin_unlock_bh(&txq->axq_lock);
return;
}
while (!list_empty(&tid->buf_q)) {
bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
ASSERT(!bf_isretried(bf));
list_move_tail(&bf->list, &bf_head);
ath_tx_send_normal(sc, txq, tid, &bf_head);
}
spin_unlock_bh(&txq->axq_lock);
}
static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
int seqno)
{
int index, cindex;
index = ATH_BA_INDEX(tid->seq_start, seqno);
cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
tid->tx_buf[cindex] = NULL;
while (tid->baw_head != tid->baw_tail && !tid->tx_buf[tid->baw_head]) {
INCR(tid->seq_start, IEEE80211_SEQ_MAX);
INCR(tid->baw_head, ATH_TID_MAX_BUFS);
}
}
static void ath_tx_addto_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
struct ath_buf *bf)
{
int index, cindex;
if (bf_isretried(bf))
return;
index = ATH_BA_INDEX(tid->seq_start, bf->bf_seqno);
cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
ASSERT(tid->tx_buf[cindex] == NULL);
tid->tx_buf[cindex] = bf;
if (index >= ((tid->baw_tail - tid->baw_head) &
(ATH_TID_MAX_BUFS - 1))) {
tid->baw_tail = cindex;
INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
}
}
/*
* TODO: For frame(s) that are in the retry state, we will reuse the
* sequence number(s) without setting the retry bit. The
* alternative is to give up on these and BAR the receiver's window
* forward.
*/
static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
struct ath_atx_tid *tid)
{
struct ath_buf *bf;
struct list_head bf_head;
INIT_LIST_HEAD(&bf_head);
for (;;) {
if (list_empty(&tid->buf_q))
break;
bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
list_move_tail(&bf->list, &bf_head);
if (bf_isretried(bf))
ath_tx_update_baw(sc, tid, bf->bf_seqno);
spin_unlock(&txq->axq_lock);
ath_tx_complete_buf(sc, bf, &bf_head, 0, 0);
spin_lock(&txq->axq_lock);
}
tid->seq_next = tid->seq_start;
tid->baw_tail = tid->baw_head;
}
static void ath_tx_set_retry(struct ath_softc *sc, struct ath_buf *bf)
{
struct sk_buff *skb;
struct ieee80211_hdr *hdr;
bf->bf_state.bf_type |= BUF_RETRY;
bf->bf_retries++;
skb = bf->bf_mpdu;
hdr = (struct ieee80211_hdr *)skb->data;
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
}
static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
{
struct ath_buf *tbf;
spin_lock_bh(&sc->tx.txbuflock);
ASSERT(!list_empty((&sc->tx.txbuf)));
tbf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
list_del(&tbf->list);
spin_unlock_bh(&sc->tx.txbuflock);
ATH_TXBUF_RESET(tbf);
tbf->bf_mpdu = bf->bf_mpdu;
tbf->bf_buf_addr = bf->bf_buf_addr;
*(tbf->bf_desc) = *(bf->bf_desc);
tbf->bf_state = bf->bf_state;
tbf->bf_dmacontext = bf->bf_dmacontext;
return tbf;
}
static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
struct ath_buf *bf, struct list_head *bf_q,
int txok)
{
struct ath_node *an = NULL;
struct sk_buff *skb;
struct ieee80211_sta *sta;
struct ieee80211_hdr *hdr;
struct ath_atx_tid *tid = NULL;
struct ath_buf *bf_next, *bf_last = bf->bf_lastbf;
struct ath_desc *ds = bf_last->bf_desc;
struct list_head bf_head, bf_pending;
u16 seq_st = 0;
u32 ba[WME_BA_BMP_SIZE >> 5];
int isaggr, txfail, txpending, sendbar = 0, needreset = 0;
skb = (struct sk_buff *)bf->bf_mpdu;
hdr = (struct ieee80211_hdr *)skb->data;
rcu_read_lock();
sta = ieee80211_find_sta(sc->hw, hdr->addr1);
if (!sta) {
rcu_read_unlock();
return;
}
an = (struct ath_node *)sta->drv_priv;
tid = ATH_AN_2_TID(an, bf->bf_tidno);
isaggr = bf_isaggr(bf);
memset(ba, 0, WME_BA_BMP_SIZE >> 3);
if (isaggr && txok) {
if (ATH_DS_TX_BA(ds)) {
seq_st = ATH_DS_BA_SEQ(ds);
memcpy(ba, ATH_DS_BA_BITMAP(ds),
WME_BA_BMP_SIZE >> 3);
} else {
/*
* AR5416 can become deaf/mute when BA
* issue happens. Chip needs to be reset.
* But AP code may have sychronization issues
* when perform internal reset in this routine.
* Only enable reset in STA mode for now.
*/
if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION)
needreset = 1;
}
}
INIT_LIST_HEAD(&bf_pending);
INIT_LIST_HEAD(&bf_head);
while (bf) {
txfail = txpending = 0;
bf_next = bf->bf_next;
if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, bf->bf_seqno))) {
/* transmit completion, subframe is
* acked by block ack */
} else if (!isaggr && txok) {
/* transmit completion */
} else {
if (!(tid->state & AGGR_CLEANUP) &&
ds->ds_txstat.ts_flags != ATH9K_TX_SW_ABORTED) {
if (bf->bf_retries < ATH_MAX_SW_RETRIES) {
ath_tx_set_retry(sc, bf);
txpending = 1;
} else {
bf->bf_state.bf_type |= BUF_XRETRY;
txfail = 1;
sendbar = 1;
}
} else {
/*
* cleanup in progress, just fail
* the un-acked sub-frames
*/
txfail = 1;
}
}
if (bf_next == NULL) {
INIT_LIST_HEAD(&bf_head);
} else {
ASSERT(!list_empty(bf_q));
list_move_tail(&bf->list, &bf_head);
}
if (!txpending) {
/*
* complete the acked-ones/xretried ones; update
* block-ack window
*/
spin_lock_bh(&txq->axq_lock);
ath_tx_update_baw(sc, tid, bf->bf_seqno);
spin_unlock_bh(&txq->axq_lock);
ath_tx_complete_buf(sc, bf, &bf_head, !txfail, sendbar);
} else {
/* retry the un-acked ones */
if (bf->bf_next == NULL &&
bf_last->bf_status & ATH_BUFSTATUS_STALE) {
struct ath_buf *tbf;
tbf = ath_clone_txbuf(sc, bf_last);
ath9k_hw_cleartxdesc(sc->sc_ah, tbf->bf_desc);
list_add_tail(&tbf->list, &bf_head);
} else {
/*
* Clear descriptor status words for
* software retry
*/
ath9k_hw_cleartxdesc(sc->sc_ah, bf->bf_desc);
}
/*
* Put this buffer to the temporary pending
* queue to retain ordering
*/
list_splice_tail_init(&bf_head, &bf_pending);
}
bf = bf_next;
}
if (tid->state & AGGR_CLEANUP) {
if (tid->baw_head == tid->baw_tail) {
tid->state &= ~AGGR_ADDBA_COMPLETE;
tid->addba_exchangeattempts = 0;
tid->state &= ~AGGR_CLEANUP;
/* send buffered frames as singles */
ath_tx_flush_tid(sc, tid);
}
rcu_read_unlock();
return;
}
/* prepend un-acked frames to the beginning of the pending frame queue */
if (!list_empty(&bf_pending)) {
spin_lock_bh(&txq->axq_lock);
list_splice(&bf_pending, &tid->buf_q);
ath_tx_queue_tid(txq, tid);
spin_unlock_bh(&txq->axq_lock);
}
rcu_read_unlock();
if (needreset)
ath_reset(sc, false);
}
static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf,
struct ath_atx_tid *tid)
{
struct ath_rate_table *rate_table = sc->cur_rate_table;
struct sk_buff *skb;
struct ieee80211_tx_info *tx_info;
struct ieee80211_tx_rate *rates;
struct ath_tx_info_priv *tx_info_priv;
u32 max_4ms_framelen, frmlen;
u16 aggr_limit, legacy = 0, maxampdu;
int i;
skb = (struct sk_buff *)bf->bf_mpdu;
tx_info = IEEE80211_SKB_CB(skb);
rates = tx_info->control.rates;
tx_info_priv = (struct ath_tx_info_priv *)tx_info->rate_driver_data[0];
/*
* Find the lowest frame length among the rate series that will have a
* 4ms transmit duration.
* TODO - TXOP limit needs to be considered.
*/
max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
for (i = 0; i < 4; i++) {
if (rates[i].count) {
if (!WLAN_RC_PHY_HT(rate_table->info[rates[i].idx].phy)) {
legacy = 1;
break;
}
frmlen = rate_table->info[rates[i].idx].max_4ms_framelen;
max_4ms_framelen = min(max_4ms_framelen, frmlen);
}
}
/*
* limit aggregate size by the minimum rate if rate selected is
* not a probe rate, if rate selected is a probe rate then
* avoid aggregation of this packet.
*/
if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
return 0;
aggr_limit = min(max_4ms_framelen, (u32)ATH_AMPDU_LIMIT_DEFAULT);
/*
* h/w can accept aggregates upto 16 bit lengths (65535).
* The IE, however can hold upto 65536, which shows up here
* as zero. Ignore 65536 since we are constrained by hw.
*/
maxampdu = tid->an->maxampdu;
if (maxampdu)
aggr_limit = min(aggr_limit, maxampdu);
return aggr_limit;
}
/*
* Returns the number of delimiters to be added to
* meet the minimum required mpdudensity.
* caller should make sure that the rate is HT rate .
*/
static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
struct ath_buf *bf, u16 frmlen)
{
struct ath_rate_table *rt = sc->cur_rate_table;
struct sk_buff *skb = bf->bf_mpdu;
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
u32 nsymbits, nsymbols, mpdudensity;
u16 minlen;
u8 rc, flags, rix;
int width, half_gi, ndelim, mindelim;
/* Select standard number of delimiters based on frame length alone */
ndelim = ATH_AGGR_GET_NDELIM(frmlen);
/*
* If encryption enabled, hardware requires some more padding between
* subframes.
* TODO - this could be improved to be dependent on the rate.
* The hardware can keep up at lower rates, but not higher rates
*/
if (bf->bf_keytype != ATH9K_KEY_TYPE_CLEAR)
ndelim += ATH_AGGR_ENCRYPTDELIM;
/*
* Convert desired mpdu density from microeconds to bytes based
* on highest rate in rate series (i.e. first rate) to determine
* required minimum length for subframe. Take into account
* whether high rate is 20 or 40Mhz and half or full GI.
*/
mpdudensity = tid->an->mpdudensity;
/*
* If there is no mpdu density restriction, no further calculation
* is needed.
*/
if (mpdudensity == 0)
return ndelim;
rix = tx_info->control.rates[0].idx;
flags = tx_info->control.rates[0].flags;
rc = rt->info[rix].ratecode;
width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
if (half_gi)
nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(mpdudensity);
else
nsymbols = NUM_SYMBOLS_PER_USEC(mpdudensity);
if (nsymbols == 0)
nsymbols = 1;
nsymbits = bits_per_symbol[HT_RC_2_MCS(rc)][width];
minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
if (frmlen < minlen) {
mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
ndelim = max(mindelim, ndelim);
}
return ndelim;
}
static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
struct ath_atx_tid *tid,
struct list_head *bf_q)
{
#define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
struct ath_buf *bf, *bf_first, *bf_prev = NULL;
int rl = 0, nframes = 0, ndelim, prev_al = 0;
u16 aggr_limit = 0, al = 0, bpad = 0,
al_delta, h_baw = tid->baw_size / 2;
enum ATH_AGGR_STATUS status = ATH_AGGR_DONE;
bf_first = list_first_entry(&tid->buf_q, struct ath_buf, list);
do {
bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
/* do not step over block-ack window */
if (!BAW_WITHIN(tid->seq_start, tid->baw_size, bf->bf_seqno)) {
status = ATH_AGGR_BAW_CLOSED;
break;
}
if (!rl) {
aggr_limit = ath_lookup_rate(sc, bf, tid);
rl = 1;
}
/* do not exceed aggregation limit */
al_delta = ATH_AGGR_DELIM_SZ + bf->bf_frmlen;
if (nframes &&
(aggr_limit < (al + bpad + al_delta + prev_al))) {
status = ATH_AGGR_LIMITED;
break;
}
/* do not exceed subframe limit */
if (nframes >= min((int)h_baw, ATH_AMPDU_SUBFRAME_DEFAULT)) {
status = ATH_AGGR_LIMITED;
break;
}
nframes++;
/* add padding for previous frame to aggregation length */
al += bpad + al_delta;
/*
* Get the delimiters needed to meet the MPDU
* density for this node.
*/
ndelim = ath_compute_num_delims(sc, tid, bf_first, bf->bf_frmlen);
bpad = PADBYTES(al_delta) + (ndelim << 2);
bf->bf_next = NULL;
bf->bf_desc->ds_link = 0;
/* link buffers of this frame to the aggregate */
ath_tx_addto_baw(sc, tid, bf);
ath9k_hw_set11n_aggr_middle(sc->sc_ah, bf->bf_desc, ndelim);
list_move_tail(&bf->list, bf_q);
if (bf_prev) {
bf_prev->bf_next = bf;
bf_prev->bf_desc->ds_link = bf->bf_daddr;
}
bf_prev = bf;
} while (!list_empty(&tid->buf_q));
bf_first->bf_al = al;
bf_first->bf_nframes = nframes;
return status;
#undef PADBYTES
}
static void ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
struct ath_atx_tid *tid)
{
struct ath_buf *bf;
enum ATH_AGGR_STATUS status;
struct list_head bf_q;
do {
if (list_empty(&tid->buf_q))
return;
INIT_LIST_HEAD(&bf_q);
status = ath_tx_form_aggr(sc, tid, &bf_q);
/*
* no frames picked up to be aggregated;
* block-ack window is not open.
*/
if (list_empty(&bf_q))
break;
bf = list_first_entry(&bf_q, struct ath_buf, list);
bf->bf_lastbf = list_entry(bf_q.prev, struct ath_buf, list);
/* if only one frame, send as non-aggregate */
if (bf->bf_nframes == 1) {
bf->bf_state.bf_type &= ~BUF_AGGR;
ath9k_hw_clr11n_aggr(sc->sc_ah, bf->bf_desc);
ath_buf_set_rate(sc, bf);
ath_tx_txqaddbuf(sc, txq, &bf_q);
continue;
}
/* setup first desc of aggregate */
bf->bf_state.bf_type |= BUF_AGGR;
ath_buf_set_rate(sc, bf);
ath9k_hw_set11n_aggr_first(sc->sc_ah, bf->bf_desc, bf->bf_al);
/* anchor last desc of aggregate */
ath9k_hw_set11n_aggr_last(sc->sc_ah, bf->bf_lastbf->bf_desc);
txq->axq_aggr_depth++;
ath_tx_txqaddbuf(sc, txq, &bf_q);
} while (txq->axq_depth < ATH_AGGR_MIN_QDEPTH &&
status != ATH_AGGR_BAW_CLOSED);
}
int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
u16 tid, u16 *ssn)
{
struct ath_atx_tid *txtid;
struct ath_node *an;
an = (struct ath_node *)sta->drv_priv;
if (sc->sc_flags & SC_OP_TXAGGR) {
txtid = ATH_AN_2_TID(an, tid);
txtid->state |= AGGR_ADDBA_PROGRESS;
ath_tx_pause_tid(sc, txtid);
*ssn = txtid->seq_start;
}
return 0;
}
int ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
{
struct ath_node *an = (struct ath_node *)sta->drv_priv;
struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
struct ath_txq *txq = &sc->tx.txq[txtid->ac->qnum];
struct ath_buf *bf;
struct list_head bf_head;
INIT_LIST_HEAD(&bf_head);
if (txtid->state & AGGR_CLEANUP)
return 0;
if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
txtid->addba_exchangeattempts = 0;
return 0;
}
ath_tx_pause_tid(sc, txtid);
/* drop all software retried frames and mark this TID */
spin_lock_bh(&txq->axq_lock);
while (!list_empty(&txtid->buf_q)) {
bf = list_first_entry(&txtid->buf_q, struct ath_buf, list);
if (!bf_isretried(bf)) {
/*
* NB: it's based on the assumption that
* software retried frame will always stay
* at the head of software queue.
*/
break;
}
list_move_tail(&bf->list, &bf_head);
ath_tx_update_baw(sc, txtid, bf->bf_seqno);
ath_tx_complete_buf(sc, bf, &bf_head, 0, 0);
}
spin_unlock_bh(&txq->axq_lock);
if (txtid->baw_head != txtid->baw_tail) {
txtid->state |= AGGR_CLEANUP;
} else {
txtid->state &= ~AGGR_ADDBA_COMPLETE;
txtid->addba_exchangeattempts = 0;
ath_tx_flush_tid(sc, txtid);
}
return 0;
}
void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
{
struct ath_atx_tid *txtid;
struct ath_node *an;
an = (struct ath_node *)sta->drv_priv;
if (sc->sc_flags & SC_OP_TXAGGR) {
txtid = ATH_AN_2_TID(an, tid);
txtid->baw_size =
IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
txtid->state |= AGGR_ADDBA_COMPLETE;
txtid->state &= ~AGGR_ADDBA_PROGRESS;
ath_tx_resume_tid(sc, txtid);
}
}
bool ath_tx_aggr_check(struct ath_softc *sc, struct ath_node *an, u8 tidno)
{
struct ath_atx_tid *txtid;
if (!(sc->sc_flags & SC_OP_TXAGGR))
return false;
txtid = ATH_AN_2_TID(an, tidno);
if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
if (!(txtid->state & AGGR_ADDBA_PROGRESS) &&
(txtid->addba_exchangeattempts < ADDBA_EXCHANGE_ATTEMPTS)) {
txtid->addba_exchangeattempts++;
return true;
}
}
return false;
}
/********************/
/* Queue Management */
/********************/
static u32 ath_txq_depth(struct ath_softc *sc, int qnum)
{
return sc->tx.txq[qnum].axq_depth;
}
static void ath_get_beaconconfig(struct ath_softc *sc, int if_id,
struct ath_beacon_config *conf)
{
struct ieee80211_hw *hw = sc->hw;
/* fill in beacon config data */
conf->beacon_interval = hw->conf.beacon_int;
conf->listen_interval = 100;
conf->dtim_count = 1;
conf->bmiss_timeout = ATH_DEFAULT_BMISS_LIMIT * conf->listen_interval;
}
static void ath_txq_drain_pending_buffers(struct ath_softc *sc,
struct ath_txq *txq)
{
struct ath_atx_ac *ac, *ac_tmp;
struct ath_atx_tid *tid, *tid_tmp;
list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
list_del(&ac->list);
ac->sched = false;
list_for_each_entry_safe(tid, tid_tmp, &ac->tid_q, list) {
list_del(&tid->list);
tid->sched = false;
ath_tid_drain(sc, txq, tid);
}
}
}
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;
int qnum;
memset(&qi, 0, sizeof(qi));
qi.tqi_subtype = 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.
*/
if (qtype == ATH9K_TX_QUEUE_UAPSD)
qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
else
qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
TXQ_FLAG_TXDESCINT_ENABLE;
qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
if (qnum == -1) {
/*
* NB: don't print a message, this happens
* normally on parts with too few tx queues
*/
return NULL;
}
if (qnum >= ARRAY_SIZE(sc->tx.txq)) {
DPRINTF(sc, ATH_DBG_FATAL,
"qnum %u out of range, max %u!\n",
qnum, (unsigned int)ARRAY_SIZE(sc->tx.txq));
ath9k_hw_releasetxqueue(ah, qnum);
return NULL;
}
if (!ATH_TXQ_SETUP(sc, qnum)) {
struct ath_txq *txq = &sc->tx.txq[qnum];
txq->axq_qnum = qnum;
txq->axq_link = NULL;
INIT_LIST_HEAD(&txq->axq_q);
INIT_LIST_HEAD(&txq->axq_acq);
spin_lock_init(&txq->axq_lock);
txq->axq_depth = 0;
txq->axq_aggr_depth = 0;
txq->axq_totalqueued = 0;
txq->axq_linkbuf = NULL;
sc->tx.txqsetup |= 1<<qnum;
}
return &sc->tx.txq[qnum];
}
static int ath_tx_get_qnum(struct ath_softc *sc, int qtype, int haltype)
{
int qnum;
switch (qtype) {
case ATH9K_TX_QUEUE_DATA:
if (haltype >= ARRAY_SIZE(sc->tx.hwq_map)) {
DPRINTF(sc, ATH_DBG_FATAL,
"HAL AC %u out of range, max %zu!\n",
haltype, ARRAY_SIZE(sc->tx.hwq_map));
return -1;
}
qnum = sc->tx.hwq_map[haltype];
break;
case ATH9K_TX_QUEUE_BEACON:
qnum = sc->beacon.beaconq;
break;
case ATH9K_TX_QUEUE_CAB:
qnum = sc->beacon.cabq->axq_qnum;
break;
default:
qnum = -1;
}
return qnum;
}
struct ath_txq *ath_test_get_txq(struct ath_softc *sc, struct sk_buff *skb)
{
struct ath_txq *txq = NULL;
int qnum;
qnum = ath_get_hal_qnum(skb_get_queue_mapping(skb), sc);
txq = &sc->tx.txq[qnum];
spin_lock_bh(&txq->axq_lock);
if (txq->axq_depth >= (ATH_TXBUF - 20)) {
DPRINTF(sc, ATH_DBG_FATAL,
"TX queue: %d is full, depth: %d\n",
qnum, txq->axq_depth);
ieee80211_stop_queue(sc->hw, skb_get_queue_mapping(skb));
txq->stopped = 1;
spin_unlock_bh(&txq->axq_lock);
return NULL;
}
spin_unlock_bh(&txq->axq_lock);
return txq;
}
int ath_txq_update(struct ath_softc *sc, int qnum,
struct ath9k_tx_queue_info *qinfo)
{
struct ath_hw *ah = sc->sc_ah;
int error = 0;
struct ath9k_tx_queue_info qi;
if (qnum == sc->beacon.beaconq) {
/*
* XXX: for beacon queue, we just save the parameter.
* It will be picked up by ath_beaconq_config when
* it's necessary.
*/
sc->beacon.beacon_qi = *qinfo;
return 0;
}
ASSERT(sc->tx.txq[qnum].axq_qnum == qnum);
ath9k_hw_get_txq_props(ah, qnum, &qi);
qi.tqi_aifs = qinfo->tqi_aifs;
qi.tqi_cwmin = qinfo->tqi_cwmin;
qi.tqi_cwmax = qinfo->tqi_cwmax;
qi.tqi_burstTime = qinfo->tqi_burstTime;
qi.tqi_readyTime = qinfo->tqi_readyTime;
if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
DPRINTF(sc, ATH_DBG_FATAL,
"Unable to update hardware queue %u!\n", qnum);
error = -EIO;
} else {
ath9k_hw_resettxqueue(ah, qnum);
}
return error;
}
int ath_cabq_update(struct ath_softc *sc)
{
struct ath9k_tx_queue_info qi;
int qnum = sc->beacon.cabq->axq_qnum;
struct ath_beacon_config conf;
ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
/*
* Ensure the readytime % is within the bounds.
*/
if (sc->config.cabqReadytime < ATH9K_READY_TIME_LO_BOUND)
sc->config.cabqReadytime = ATH9K_READY_TIME_LO_BOUND;
else if (sc->config.cabqReadytime > ATH9K_READY_TIME_HI_BOUND)
sc->config.cabqReadytime = ATH9K_READY_TIME_HI_BOUND;
ath_get_beaconconfig(sc, ATH_IF_ID_ANY, &conf);
qi.tqi_readyTime =
(conf.beacon_interval * sc->config.cabqReadytime) / 100;
ath_txq_update(sc, qnum, &qi);
return 0;
}
/*
* 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, bool retry_tx)
{
struct ath_buf *bf, *lastbf;
struct list_head bf_head;
INIT_LIST_HEAD(&bf_head);
for (;;) {
spin_lock_bh(&txq->axq_lock);
if (list_empty(&txq->axq_q)) {
txq->axq_link = NULL;
txq->axq_linkbuf = NULL;
spin_unlock_bh(&txq->axq_lock);
break;
}
bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
if (bf->bf_status & ATH_BUFSTATUS_STALE) {
list_del(&bf->list);
spin_unlock_bh(&txq->axq_lock);
spin_lock_bh(&sc->tx.txbuflock);
list_add_tail(&bf->list, &sc->tx.txbuf);
spin_unlock_bh(&sc->tx.txbuflock);
continue;
}
lastbf = bf->bf_lastbf;
if (!retry_tx)
lastbf->bf_desc->ds_txstat.ts_flags =
ATH9K_TX_SW_ABORTED;
/* remove ath_buf's of the same mpdu from txq */
list_cut_position(&bf_head, &txq->axq_q, &lastbf->list);
txq->axq_depth--;
spin_unlock_bh(&txq->axq_lock);
if (bf_isampdu(bf))
ath_tx_complete_aggr(sc, txq, bf, &bf_head, 0);
else
ath_tx_complete_buf(sc, bf, &bf_head, 0, 0);
}
/* flush any pending frames if aggregation is enabled */
if (sc->sc_flags & SC_OP_TXAGGR) {
if (!retry_tx) {
spin_lock_bh(&txq->axq_lock);
ath_txq_drain_pending_buffers(sc, txq);
spin_unlock_bh(&txq->axq_lock);
}
}
}
void ath_drain_all_txq(struct ath_softc *sc, bool 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;
/* Stop beacon queue */
ath9k_hw_stoptxdma(sc->sc_ah, sc->beacon.beaconq);
/* Stop data queues */
for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
if (ATH_TXQ_SETUP(sc, i)) {
txq = &sc->tx.txq[i];
ath9k_hw_stoptxdma(ah, txq->axq_qnum);
npend += ath9k_hw_numtxpending(ah, txq->axq_qnum);
}
}
if (npend) {
int r;
DPRINTF(sc, ATH_DBG_XMIT, "Unable to stop TxDMA. Reset HAL!\n");
spin_lock_bh(&sc->sc_resetlock);
r = ath9k_hw_reset(ah, sc->sc_ah->curchan, true);
if (r)
DPRINTF(sc, ATH_DBG_FATAL,
"Unable to reset hardware; reset status %u\n",
r);
spin_unlock_bh(&sc->sc_resetlock);
}
for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
if (ATH_TXQ_SETUP(sc, i))
ath_draintxq(sc, &sc->tx.txq[i], retry_tx);
}
}
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);
}
void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
{
struct ath_atx_ac *ac;
struct ath_atx_tid *tid;
if (list_empty(&txq->axq_acq))
return;
ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
list_del(&ac->list);
ac->sched = false;
do {
if (list_empty(&ac->tid_q))
return;
tid = list_first_entry(&ac->tid_q, struct ath_atx_tid, list);
list_del(&tid->list);
tid->sched = false;
if (tid->paused)
continue;
if ((txq->axq_depth % 2) == 0)
ath_tx_sched_aggr(sc, txq, tid);
/*
* 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);
break;
} while (!list_empty(&ac->tid_q));
if (!list_empty(&ac->tid_q)) {
if (!ac->sched) {
ac->sched = true;
list_add_tail(&ac->list, &txq->axq_acq);
}
}
}
int ath_tx_setup(struct ath_softc *sc, int haltype)
{
struct ath_txq *txq;
if (haltype >= ARRAY_SIZE(sc->tx.hwq_map)) {
DPRINTF(sc, ATH_DBG_FATAL,
"HAL AC %u out of range, max %zu!\n",
haltype, ARRAY_SIZE(sc->tx.hwq_map));
return 0;
}
txq = ath_txq_setup(sc, ATH9K_TX_QUEUE_DATA, haltype);
if (txq != NULL) {
sc->tx.hwq_map[haltype] = txq->axq_qnum;
return 1;
} else
return 0;
}
/***********/
/* 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);
list_splice_tail_init(head, &txq->axq_q);
txq->axq_depth++;
txq->axq_totalqueued++;
txq->axq_linkbuf = list_entry(txq->axq_q.prev, struct ath_buf, list);
DPRINTF(sc, ATH_DBG_QUEUE,
"qnum: %d, txq depth: %d\n", txq->axq_qnum, txq->axq_depth);
if (txq->axq_link == NULL) {
ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
DPRINTF(sc, ATH_DBG_XMIT,
"TXDP[%u] = %llx (%p)\n",
txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
} else {
*txq->axq_link = bf->bf_daddr;
DPRINTF(sc, ATH_DBG_XMIT, "link[%u] (%p)=%llx (%p)\n",
txq->axq_qnum, txq->axq_link,
ito64(bf->bf_daddr), bf->bf_desc);
}
txq->axq_link = &(bf->bf_lastbf->bf_desc->ds_link);
ath9k_hw_txstart(ah, txq->axq_qnum);
}
static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
{
struct ath_buf *bf = NULL;
spin_lock_bh(&sc->tx.txbuflock);
if (unlikely(list_empty(&sc->tx.txbuf))) {
spin_unlock_bh(&sc->tx.txbuflock);
return NULL;
}
bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
list_del(&bf->list);
spin_unlock_bh(&sc->tx.txbuflock);
return bf;
}
static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid,
struct list_head *bf_head,
struct ath_tx_control *txctl)
{
struct ath_buf *bf;
bf = list_first_entry(bf_head, struct ath_buf, list);
bf->bf_state.bf_type |= BUF_AMPDU;
/*
* Do not queue to h/w when any of the following conditions is true:
* - there are pending frames in software queue
* - the TID is currently paused for ADDBA/BAR request
* - seqno is not within block-ack window
* - h/w queue depth exceeds low water mark
*/
if (!list_empty(&tid->buf_q) || tid->paused ||
!BAW_WITHIN(tid->seq_start, tid->baw_size, bf->bf_seqno) ||
txctl->txq->axq_depth >= ATH_AGGR_MIN_QDEPTH) {
/*
* Add this frame to software queue for scheduling later
* for aggregation.
*/
list_move_tail(&bf->list, &tid->buf_q);
ath_tx_queue_tid(txctl->txq, tid);
return;
}
/* Add sub-frame to BAW */
ath_tx_addto_baw(sc, tid, bf);
/* Queue to h/w without aggregation */
bf->bf_nframes = 1;
bf->bf_lastbf = bf;
ath_buf_set_rate(sc, bf);
ath_tx_txqaddbuf(sc, txctl->txq, bf_head);
}
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 */
INCR(tid->seq_start, IEEE80211_SEQ_MAX);
bf->bf_nframes = 1;
bf->bf_lastbf = bf;
ath_buf_set_rate(sc, bf);
ath_tx_txqaddbuf(sc, txq, bf_head);
}
static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
{
struct ieee80211_hdr *hdr;
enum ath9k_pkt_type htype;
__le16 fc;
hdr = (struct ieee80211_hdr *)skb->data;
fc = hdr->frame_control;
if (ieee80211_is_beacon(fc))
htype = ATH9K_PKT_TYPE_BEACON;
else if (ieee80211_is_probe_resp(fc))
htype = ATH9K_PKT_TYPE_PROBE_RESP;
else if (ieee80211_is_atim(fc))
htype = ATH9K_PKT_TYPE_ATIM;
else if (ieee80211_is_pspoll(fc))
htype = ATH9K_PKT_TYPE_PSPOLL;
else
htype = ATH9K_PKT_TYPE_NORMAL;
return htype;
}
static bool is_pae(struct sk_buff *skb)
{
struct ieee80211_hdr *hdr;
__le16 fc;
hdr = (struct ieee80211_hdr *)skb->data;
fc = hdr->frame_control;
if (ieee80211_is_data(fc)) {
if (ieee80211_is_nullfunc(fc) ||
/* Port Access Entity (IEEE 802.1X) */
(skb->protocol == cpu_to_be16(ETH_P_PAE))) {
return true;
}
}
return false;
}
static int get_hw_crypto_keytype(struct sk_buff *skb)
{
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
if (tx_info->control.hw_key) {
if (tx_info->control.hw_key->alg == ALG_WEP)
return ATH9K_KEY_TYPE_WEP;
else if (tx_info->control.hw_key->alg == ALG_TKIP)
return ATH9K_KEY_TYPE_TKIP;
else if (tx_info->control.hw_key->alg == ALG_CCMP)
return ATH9K_KEY_TYPE_AES;
}
return ATH9K_KEY_TYPE_CLEAR;
}
static void assign_aggr_tid_seqno(struct sk_buff *skb,
struct ath_buf *bf)
{
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr;
struct ath_node *an;
struct ath_atx_tid *tid;
__le16 fc;
u8 *qc;
if (!tx_info->control.sta)
return;
an = (struct ath_node *)tx_info->control.sta->drv_priv;
hdr = (struct ieee80211_hdr *)skb->data;
fc = hdr->frame_control;
if (ieee80211_is_data_qos(fc)) {
qc = ieee80211_get_qos_ctl(hdr);
bf->bf_tidno = qc[0] & 0xf;
}
/*
* For HT capable stations, we save tidno for later use.
* We also override seqno set by upper layer with the one
* in tx aggregation state.
*
* If fragmentation is on, the sequence number is
* not overridden, since it has been
* incremented by the fragmentation routine.
*
* FIXME: check if the fragmentation threshold exceeds
* IEEE80211 max.
*/
tid = ATH_AN_2_TID(an, bf->bf_tidno);
hdr->seq_ctrl = cpu_to_le16(tid->seq_next <<
IEEE80211_SEQ_SEQ_SHIFT);
bf->bf_seqno = tid->seq_next;
INCR(tid->seq_next, IEEE80211_SEQ_MAX);
}
static int setup_tx_flags(struct ath_softc *sc, struct sk_buff *skb,
struct ath_txq *txq)
{
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
int flags = 0;
flags |= ATH9K_TXDESC_CLRDMASK; /* needed for crypto errors */
flags |= ATH9K_TXDESC_INTREQ;
if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
flags |= ATH9K_TXDESC_NOACK;
return flags;
}
/*
* rix - rate index
* pktlen - total bytes (delims + data + fcs + pads + pad delims)
* width - 0 for 20 MHz, 1 for 40 MHz
* half_gi - to use 4us v/s 3.6 us for symbol time
*/
static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, struct ath_buf *bf,
int width, int half_gi, bool shortPreamble)
{
struct ath_rate_table *rate_table = sc->cur_rate_table;
u32 nbits, nsymbits, duration, nsymbols;
u8 rc;
int streams, pktlen;
pktlen = bf_isaggr(bf) ? bf->bf_al : bf->bf_frmlen;
rc = rate_table->info[rix].ratecode;
/* for legacy rates, use old function to compute packet duration */
if (!IS_HT_RATE(rc))
return ath9k_hw_computetxtime(sc->sc_ah, rate_table, pktlen,
rix, shortPreamble);
/* find number of symbols: PLCP + data */
nbits = (pktlen << 3) + OFDM_PLCP_BITS;
nsymbits = bits_per_symbol[HT_RC_2_MCS(rc)][width];
nsymbols = (nbits + nsymbits - 1) / nsymbits;
if (!half_gi)
duration = SYMBOL_TIME(nsymbols);
else
duration = SYMBOL_TIME_HALFGI(nsymbols);
/* addup duration for legacy/ht training and signal fields */
streams = HT_RC_2_STREAMS(rc);
duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
return duration;
}
static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf)
{
struct ath_rate_table *rt = sc->cur_rate_table;
struct ath9k_11n_rate_series series[4];
struct sk_buff *skb;
struct ieee80211_tx_info *tx_info;
struct ieee80211_tx_rate *rates;
struct ieee80211_hdr *hdr;
int i, flags = 0;
u8 rix = 0, ctsrate = 0;
bool is_pspoll;
memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
skb = (struct sk_buff *)bf->bf_mpdu;
tx_info = IEEE80211_SKB_CB(skb);
rates = tx_info->control.rates;
hdr = (struct ieee80211_hdr *)skb->data;
is_pspoll = ieee80211_is_pspoll(hdr->frame_control);
/*
* 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.
*/
if (sc->sc_flags & SC_OP_PREAMBLE_SHORT)
ctsrate = rt->info[tx_info->control.rts_cts_rate_idx].ratecode |
rt->info[tx_info->control.rts_cts_rate_idx].short_preamble;
else
ctsrate = rt->info[tx_info->control.rts_cts_rate_idx].ratecode;
/*
* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive.
* Check the first rate in the series to decide whether RTS/CTS
* or CTS-to-self has to be used.
*/
if (rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
flags = ATH9K_TXDESC_CTSENA;
else if (rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
flags = ATH9K_TXDESC_RTSENA;
/* FIXME: Handle aggregation protection */
if (sc->config.ath_aggr_prot &&
(!bf_isaggr(bf) || (bf_isaggr(bf) && bf->bf_al < 8192))) {
flags = ATH9K_TXDESC_RTSENA;
}
/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
if (bf_isaggr(bf) && (bf->bf_al > sc->sc_ah->caps.rts_aggr_limit))
flags &= ~(ATH9K_TXDESC_RTSENA);
for (i = 0; i < 4; i++) {
if (!rates[i].count || (rates[i].idx < 0))
continue;
rix = rates[i].idx;
series[i].Tries = rates[i].count;
series[i].ChSel = sc->tx_chainmask;
if (rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
series[i].Rate = rt->info[rix].ratecode |
rt->info[rix].short_preamble;
else
series[i].Rate = rt->info[rix].ratecode;
if (rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS)
series[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
series[i].RateFlags |= ATH9K_RATESERIES_2040;
if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
series[i].RateFlags |= ATH9K_RATESERIES_HALFGI;
series[i].PktDuration = ath_pkt_duration(sc, rix, bf,
(rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH) != 0,
(rates[i].flags & IEEE80211_TX_RC_SHORT_GI),
(rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE));
}
/* 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);
if (sc->config.ath_aggr_prot && flags)
ath9k_hw_set11n_burstduration(sc->sc_ah, bf->bf_desc, 8192);
}
static int ath_tx_setup_buffer(struct ath_softc *sc, struct ath_buf *bf,
struct sk_buff *skb,
struct ath_tx_control *txctl)
{
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
struct ath_tx_info_priv *tx_info_priv;
int hdrlen;
__le16 fc;
tx_info_priv = kzalloc(sizeof(*tx_info_priv), GFP_ATOMIC);
if (unlikely(!tx_info_priv))
return -ENOMEM;
tx_info->rate_driver_data[0] = tx_info_priv;
hdrlen = ieee80211_get_hdrlen_from_skb(skb);
fc = hdr->frame_control;
ATH_TXBUF_RESET(bf);
bf->bf_frmlen = skb->len + FCS_LEN - (hdrlen & 3);
if ((conf_is_ht(&sc->hw->conf) && !is_pae(skb) &&
(tx_info->flags & IEEE80211_TX_CTL_AMPDU)))
bf->bf_state.bf_type |= BUF_HT;
bf->bf_flags = setup_tx_flags(sc, skb, txctl->txq);
bf->bf_keytype = get_hw_crypto_keytype(skb);
if (bf->bf_keytype != ATH9K_KEY_TYPE_CLEAR) {
bf->bf_frmlen += tx_info->control.hw_key->icv_len;
bf->bf_keyix = tx_info->control.hw_key->hw_key_idx;
} else {
bf->bf_keyix = ATH9K_TXKEYIX_INVALID;
}
if (ieee80211_is_data_qos(fc) && (sc->sc_flags & SC_OP_TXAGGR))
assign_aggr_tid_seqno(skb, bf);
bf->bf_mpdu = skb;
bf->bf_dmacontext = dma_map_single(sc->dev, skb->data,
skb->len, DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(sc->dev, bf->bf_dmacontext))) {
bf->bf_mpdu = NULL;
DPRINTF(sc, ATH_DBG_CONFIG,
"dma_mapping_error() on TX\n");
return -ENOMEM;
}
bf->bf_buf_addr = bf->bf_dmacontext;
return 0;
}
/* FIXME: tx power */
static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf,
struct ath_tx_control *txctl)
{
struct sk_buff *skb = (struct sk_buff *)bf->bf_mpdu;
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
struct ath_node *an = NULL;
struct list_head bf_head;
struct ath_desc *ds;
struct ath_atx_tid *tid;
struct ath_hw *ah = sc->sc_ah;
int frm_type;
frm_type = get_hw_packet_type(skb);
INIT_LIST_HEAD(&bf_head);
list_add_tail(&bf->list, &bf_head);
ds = bf->bf_desc;
ds->ds_link = 0;
ds->ds_data = bf->bf_buf_addr;
ath9k_hw_set11n_txdesc(ah, ds, bf->bf_frmlen, frm_type, MAX_RATE_POWER,
bf->bf_keyix, bf->bf_keytype, bf->bf_flags);
ath9k_hw_filltxdesc(ah, ds,
skb->len, /* segment length */
true, /* first segment */
true, /* last segment */
ds); /* first descriptor */
spin_lock_bh(&txctl->txq->axq_lock);
if (bf_isht(bf) && (sc->sc_flags & SC_OP_TXAGGR) &&
tx_info->control.sta) {
an = (struct ath_node *)tx_info->control.sta->drv_priv;
tid = ATH_AN_2_TID(an, bf->bf_tidno);
if (ath_aggr_query(sc, an, bf->bf_tidno)) {
/*
* Try aggregation if it's a unicast data frame
* and the destination is HT capable.
*/
ath_tx_send_ampdu(sc, tid, &bf_head, txctl);
} else {
/*
* Send this frame as regular when ADDBA
* exchange is neither complete nor pending.
*/
ath_tx_send_normal(sc, txctl->txq,
tid, &bf_head);
}
} else {
bf->bf_lastbf = bf;
bf->bf_nframes = 1;
ath_buf_set_rate(sc, bf);
ath_tx_txqaddbuf(sc, txctl->txq, &bf_head);
}
spin_unlock_bh(&txctl->txq->axq_lock);
}
/* Upon failure caller should free skb */
int ath_tx_start(struct ath_softc *sc, struct sk_buff *skb,
struct ath_tx_control *txctl)
{
struct ath_buf *bf;
int r;
bf = ath_tx_get_buffer(sc);
if (!bf) {
DPRINTF(sc, ATH_DBG_XMIT, "TX buffers are full\n");
return -1;
}
r = ath_tx_setup_buffer(sc, bf, skb, txctl);
if (unlikely(r)) {
struct ath_txq *txq = txctl->txq;
DPRINTF(sc, ATH_DBG_FATAL, "TX mem alloc failure\n");
/* upon ath_tx_processq() this TX queue will be resumed, we
* guarantee this will happen by knowing beforehand that
* we will at least have to run TX completionon one buffer
* on the queue */
spin_lock_bh(&txq->axq_lock);
if (ath_txq_depth(sc, txq->axq_qnum) > 1) {
ieee80211_stop_queue(sc->hw,
skb_get_queue_mapping(skb));
txq->stopped = 1;
}
spin_unlock_bh(&txq->axq_lock);
spin_lock_bh(&sc->tx.txbuflock);
list_add_tail(&bf->list, &sc->tx.txbuf);
spin_unlock_bh(&sc->tx.txbuflock);
return r;
}
ath_tx_start_dma(sc, bf, txctl);
return 0;
}
void ath_tx_cabq(struct ath_softc *sc, struct sk_buff *skb)
{
int hdrlen, padsize;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct ath_tx_control txctl;
memset(&txctl, 0, sizeof(struct ath_tx_control));
/*
* As a temporary workaround, assign seq# here; this will likely need
* to be cleaned up to work better with Beacon transmission and virtual
* BSSes.
*/
if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
sc->tx.seq_no += 0x10;
hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
}
/* Add the padding after the header if this is not already done */
hdrlen = ieee80211_get_hdrlen_from_skb(skb);
if (hdrlen & 3) {
padsize = hdrlen % 4;
if (skb_headroom(skb) < padsize) {
DPRINTF(sc, ATH_DBG_XMIT, "TX CABQ padding failed\n");
dev_kfree_skb_any(skb);
return;
}
skb_push(skb, padsize);
memmove(skb->data, skb->data + padsize, hdrlen);
}
txctl.txq = sc->beacon.cabq;
DPRINTF(sc, ATH_DBG_XMIT, "transmitting CABQ packet, skb: %p\n", skb);
if (ath_tx_start(sc, skb, &txctl) != 0) {
DPRINTF(sc, ATH_DBG_XMIT, "CABQ TX failed\n");
goto exit;
}
return;
exit:
dev_kfree_skb_any(skb);
}
/*****************/
/* TX Completion */
/*****************/
static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
struct ath_xmit_status *tx_status)
{
struct ieee80211_hw *hw = sc->hw;
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
struct ath_tx_info_priv *tx_info_priv = ATH_TX_INFO_PRIV(tx_info);
int hdrlen, padsize;
DPRINTF(sc, ATH_DBG_XMIT, "TX complete: skb: %p\n", skb);
if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK ||
tx_info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
kfree(tx_info_priv);
tx_info->rate_driver_data[0] = NULL;
}
if (tx_status->flags & ATH_TX_BAR) {
tx_info->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
tx_status->flags &= ~ATH_TX_BAR;
}
if (!(tx_status->flags & (ATH_TX_ERROR | ATH_TX_XRETRY))) {
/* Frame was ACKed */
tx_info->flags |= IEEE80211_TX_STAT_ACK;
}
tx_info->status.rates[0].count = tx_status->retries + 1;
hdrlen = ieee80211_get_hdrlen_from_skb(skb);
padsize = hdrlen & 3;
if (padsize && hdrlen >= 24) {
/*
* Remove MAC header padding before giving the frame back to
* mac80211.
*/
memmove(skb->data + padsize, skb->data, hdrlen);
skb_pull(skb, padsize);
}
ieee80211_tx_status(hw, skb);
}
static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
struct list_head *bf_q,
int txok, int sendbar)
{
struct sk_buff *skb = bf->bf_mpdu;
struct ath_xmit_status tx_status;
unsigned long flags;
/*
* Set retry information.
* NB: Don't use the information in the descriptor, because the frame
* could be software retried.
*/
tx_status.retries = bf->bf_retries;
tx_status.flags = 0;
if (sendbar)
tx_status.flags = ATH_TX_BAR;
if (!txok) {
tx_status.flags |= ATH_TX_ERROR;
if (bf_isxretried(bf))
tx_status.flags |= ATH_TX_XRETRY;
}
dma_unmap_single(sc->dev, bf->bf_dmacontext, skb->len, DMA_TO_DEVICE);
ath_tx_complete(sc, skb, &tx_status);
/*
* Return the list of ath_buf of this mpdu to free queue
*/
spin_lock_irqsave(&sc->tx.txbuflock, flags);
list_splice_tail_init(bf_q, &sc->tx.txbuf);
spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
}
static int ath_tx_num_badfrms(struct ath_softc *sc, struct ath_buf *bf,
int txok)
{
struct ath_buf *bf_last = bf->bf_lastbf;
struct ath_desc *ds = bf_last->bf_desc;
u16 seq_st = 0;
u32 ba[WME_BA_BMP_SIZE >> 5];
int ba_index;
int nbad = 0;
int isaggr = 0;
if (ds->ds_txstat.ts_flags == ATH9K_TX_SW_ABORTED)
return 0;
isaggr = bf_isaggr(bf);
if (isaggr) {
seq_st = ATH_DS_BA_SEQ(ds);
memcpy(ba, ATH_DS_BA_BITMAP(ds), WME_BA_BMP_SIZE >> 3);
}
while (bf) {
ba_index = ATH_BA_INDEX(seq_st, bf->bf_seqno);
if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
nbad++;
bf = bf->bf_next;
}
return nbad;
}
static void ath_tx_rc_status(struct ath_buf *bf, struct ath_desc *ds, int nbad)
{
struct sk_buff *skb = (struct sk_buff *)bf->bf_mpdu;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
struct ath_tx_info_priv *tx_info_priv = ATH_TX_INFO_PRIV(tx_info);
tx_info_priv->update_rc = false;
if (ds->ds_txstat.ts_status & ATH9K_TXERR_FILT)
tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
if ((ds->ds_txstat.ts_status & ATH9K_TXERR_FILT) == 0 &&
(bf->bf_flags & ATH9K_TXDESC_NOACK) == 0) {
if (ieee80211_is_data(hdr->frame_control)) {
memcpy(&tx_info_priv->tx, &ds->ds_txstat,
sizeof(tx_info_priv->tx));
tx_info_priv->n_frames = bf->bf_nframes;
tx_info_priv->n_bad_frames = nbad;
tx_info_priv->update_rc = true;
}
}
}
static void ath_wake_mac80211_queue(struct ath_softc *sc, struct ath_txq *txq)
{
int qnum;
spin_lock_bh(&txq->axq_lock);
if (txq->stopped &&
ath_txq_depth(sc, txq->axq_qnum) <= (ATH_TXBUF - 20)) {
qnum = ath_get_mac80211_qnum(txq->axq_qnum, sc);
if (qnum != -1) {
ieee80211_wake_queue(sc->hw, qnum);
txq->stopped = 0;
}
}
spin_unlock_bh(&txq->axq_lock);
}
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;
int txok, nbad = 0;
int status;
DPRINTF(sc, ATH_DBG_QUEUE, "tx queue %d (%x), link %p\n",
txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
txq->axq_link);
for (;;) {
spin_lock_bh(&txq->axq_lock);
if (list_empty(&txq->axq_q)) {
txq->axq_link = NULL;
txq->axq_linkbuf = NULL;
spin_unlock_bh(&txq->axq_lock);
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_status & ATH_BUFSTATUS_STALE) {
bf_held = bf;
if (list_is_last(&bf_held->list, &txq->axq_q)) {
txq->axq_link = NULL;
txq->axq_linkbuf = NULL;
spin_unlock_bh(&txq->axq_lock);
/*
* The holding descriptor is the last
* descriptor in queue. It's safe to remove
* the last holding descriptor in BH context.
*/
spin_lock_bh(&sc->tx.txbuflock);
list_move_tail(&bf_held->list, &sc->tx.txbuf);
spin_unlock_bh(&sc->tx.txbuflock);
break;
} else {
bf = list_entry(bf_held->list.next,
struct ath_buf, list);
}
}
lastbf = bf->bf_lastbf;
ds = lastbf->bf_desc;
status = ath9k_hw_txprocdesc(ah, ds);
if (status == -EINPROGRESS) {
spin_unlock_bh(&txq->axq_lock);
break;
}
if (bf->bf_desc == txq->axq_lastdsWithCTS)
txq->axq_lastdsWithCTS = NULL;
if (ds == txq->axq_gatingds)
txq->axq_gatingds = NULL;
/*
* 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_status |= ATH_BUFSTATUS_STALE;
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--;
if (bf_isaggr(bf))
txq->axq_aggr_depth--;
txok = (ds->ds_txstat.ts_status == 0);
spin_unlock_bh(&txq->axq_lock);
if (bf_held) {
spin_lock_bh(&sc->tx.txbuflock);
list_move_tail(&bf_held->list, &sc->tx.txbuf);
spin_unlock_bh(&sc->tx.txbuflock);
}
if (!bf_isampdu(bf)) {
/*
* This frame is sent out as a single frame.
* Use hardware retry status for this frame.
*/
bf->bf_retries = ds->ds_txstat.ts_longretry;
if (ds->ds_txstat.ts_status & ATH9K_TXERR_XRETRY)
bf->bf_state.bf_type |= BUF_XRETRY;
nbad = 0;
} else {
nbad = ath_tx_num_badfrms(sc, bf, txok);
}
ath_tx_rc_status(bf, ds, nbad);
if (bf_isampdu(bf))
ath_tx_complete_aggr(sc, txq, bf, &bf_head, txok);
else
ath_tx_complete_buf(sc, bf, &bf_head, txok, 0);
ath_wake_mac80211_queue(sc, txq);
spin_lock_bh(&txq->axq_lock);
if (sc->sc_flags & SC_OP_TXAGGR)
ath_txq_schedule(sc, txq);
spin_unlock_bh(&txq->axq_lock);
}
}
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;
do {
spin_lock_init(&sc->tx.txbuflock);
error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
"tx", nbufs, 1);
if (error != 0) {
DPRINTF(sc, ATH_DBG_FATAL,
"Failed to allocate tx descriptors: %d\n",
error);
break;
}
error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
"beacon", ATH_BCBUF, 1);
if (error != 0) {
DPRINTF(sc, ATH_DBG_FATAL,
"Failed to allocate beacon descriptors: %d\n",
error);
break;
}
} while (0);
if (error != 0)
ath_tx_cleanup(sc);
return error;
}
int ath_tx_cleanup(struct ath_softc *sc)
{
if (sc->beacon.bdma.dd_desc_len != 0)
ath_descdma_cleanup(sc, &sc->beacon.bdma, &sc->beacon.bbuf);
if (sc->tx.txdma.dd_desc_len != 0)
ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
return 0;
}
void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
{
struct ath_atx_tid *tid;
struct ath_atx_ac *ac;
int tidno, acno;
for (tidno = 0, tid = &an->tid[tidno];
tidno < WME_NUM_TID;
tidno++, tid++) {
tid->an = an;
tid->tidno = tidno;
tid->seq_start = tid->seq_next = 0;
tid->baw_size = WME_MAX_BA;
tid->baw_head = tid->baw_tail = 0;
tid->sched = false;
tid->paused = false;
tid->state &= ~AGGR_CLEANUP;
INIT_LIST_HEAD(&tid->buf_q);
acno = TID_TO_WME_AC(tidno);
tid->ac = &an->ac[acno];
tid->state &= ~AGGR_ADDBA_COMPLETE;
tid->state &= ~AGGR_ADDBA_PROGRESS;
tid->addba_exchangeattempts = 0;
}
for (acno = 0, ac = &an->ac[acno];
acno < WME_NUM_AC; acno++, ac++) {
ac->sched = false;
INIT_LIST_HEAD(&ac->tid_q);
switch (acno) {
case WME_AC_BE:
ac->qnum = ath_tx_get_qnum(sc,
ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_BE);
break;
case WME_AC_BK:
ac->qnum = ath_tx_get_qnum(sc,
ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_BK);
break;
case WME_AC_VI:
ac->qnum = ath_tx_get_qnum(sc,
ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_VI);
break;
case WME_AC_VO:
ac->qnum = ath_tx_get_qnum(sc,
ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_VO);
break;
}
}
}
void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
{
int i;
struct ath_atx_ac *ac, *ac_tmp;
struct ath_atx_tid *tid, *tid_tmp;
struct ath_txq *txq;
for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
if (ATH_TXQ_SETUP(sc, i)) {
txq = &sc->tx.txq[i];
spin_lock(&txq->axq_lock);
list_for_each_entry_safe(ac,
ac_tmp, &txq->axq_acq, list) {
tid = list_first_entry(&ac->tid_q,
struct ath_atx_tid, list);
if (tid && tid->an != an)
continue;
list_del(&ac->list);
ac->sched = false;
list_for_each_entry_safe(tid,
tid_tmp, &ac->tid_q, list) {
list_del(&tid->list);
tid->sched = false;
ath_tid_drain(sc, txq, tid);
tid->state &= ~AGGR_ADDBA_COMPLETE;
tid->addba_exchangeattempts = 0;
tid->state &= ~AGGR_CLEANUP;
}
}
spin_unlock(&txq->axq_lock);
}
}
}
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