ath9k: Add Tx EDMA support

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 218 insertions, 60 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 2d3e42ad3b05..fbb7dec6ddeb 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -190,6 +190,7 @@ enum ATH_AGGR_STATUS {
         ATH_AGGR_LIMITED,
 };
 
+#define ATH_TXFIFO_DEPTH 8
 struct ath_txq {
         u32 axq_qnum;
         u32 *axq_link;
@@ -199,6 +200,10 @@ struct ath_txq {
         bool stopped;
         bool axq_tx_inprogress;
         struct list_head axq_acq;
+        struct list_head txq_fifo[ATH_TXFIFO_DEPTH];
+        struct list_head txq_fifo_pending;
+        u8 txq_headidx;
+        u8 txq_tailidx;
 };
 
 #define AGGR_CLEANUP         BIT(1)
@@ -268,6 +273,7 @@ int ath_txq_update(struct ath_softc *sc, int qnum,
 int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
                  struct ath_tx_control *txctl);
 void ath_tx_tasklet(struct ath_softc *sc);
+void ath_tx_edma_tasklet(struct ath_softc *sc);
 void ath_tx_cabq(struct ieee80211_hw *hw, struct sk_buff *skb);
 bool ath_tx_aggr_check(struct ath_softc *sc, struct ath_node *an, u8 tidno);
 void ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 92f6fdc30076..1f4ea74bf4ca 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -429,8 +429,12 @@ void ath9k_tasklet(unsigned long data)
                 spin_unlock_bh(&sc->rx.rxflushlock);
         }
 
-        if (status & ATH9K_INT_TX)
-                ath_tx_tasklet(sc);
+        if (status & ATH9K_INT_TX) {
+                if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
+                        ath_tx_edma_tasklet(sc);
+                else
+                        ath_tx_tasklet(sc);
+        }
 
         if ((status & ATH9K_INT_TSFOOR) && sc->ps_enabled) {
                 /*
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index f9f7445f6652..c2b45030d0b4 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -92,7 +92,6 @@ static int ath_max_4ms_framelen[3][16] = {
         }
 };
 
-
 /*********************/
 /* Aggregation logic */
 /*********************/
@@ -379,7 +378,8 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
                         }
                 }
 
-                if (bf_next == NULL) {
+                if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
+                    bf_next == NULL) {
                         /*
                          * Make sure the last desc is reclaimed if it
                          * not a holding desc.
@@ -413,36 +413,43 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
                                 !txfail, sendbar);
                 } else {
                         /* retry the un-acked ones */
-                        if (bf->bf_next == NULL && bf_last->bf_stale) {
-                                struct ath_buf *tbf;
-
-                                tbf = ath_clone_txbuf(sc, bf_last);
-                                /*
-                                 * Update tx baw and complete the frame with
-                                 * failed status if we run out of tx buf
-                                 */
-                                if (!tbf) {
-                                        spin_lock_bh(&txq->axq_lock);
-                                        ath_tx_update_baw(sc, tid,
-                                                          bf->bf_seqno);
-                                        spin_unlock_bh(&txq->axq_lock);
-
-                                        bf->bf_state.bf_type |= BUF_XRETRY;
-                                        ath_tx_rc_status(bf, ts, nbad,
-                                                         0, false);
-                                        ath_tx_complete_buf(sc, bf, txq,
-                                                            &bf_head, ts, 0, 0);
-                                        break;
+                        if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)) {
+                                if (bf->bf_next == NULL && bf_last->bf_stale) {
+                                        struct ath_buf *tbf;
+
+                                        tbf = ath_clone_txbuf(sc, bf_last);
+                                        /*
+                                         * Update tx baw and complete the
+                                         * frame with failed status if we
+                                         * run out of tx buf.
+                                         */
+                                        if (!tbf) {
+                                                spin_lock_bh(&txq->axq_lock);
+                                                ath_tx_update_baw(sc, tid,
+                                                                bf->bf_seqno);
+                                                spin_unlock_bh(&txq->axq_lock);
+
+                                                bf->bf_state.bf_type |=
+                                                        BUF_XRETRY;
+                                                ath_tx_rc_status(bf, ts, nbad,
+                                                                0, false);
+                                                ath_tx_complete_buf(sc, bf, txq,
+                                                                    &bf_head,
+                                                                    ts, 0, 0);
+                                                break;
+                                        }
+
+                                        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);
                                 }
-
-                                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);
                         }
 
                         /*
@@ -855,7 +862,7 @@ struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
         struct ath_hw *ah = sc->sc_ah;
         struct ath_common *common = ath9k_hw_common(ah);
         struct ath9k_tx_queue_info qi;
-        int qnum;
+        int qnum, i;
 
         memset(&qi, 0, sizeof(qi));
         qi.tqi_subtype = subtype;
@@ -910,6 +917,11 @@ struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
                 txq->axq_depth = 0;
                 txq->axq_tx_inprogress = false;
                 sc->tx.txqsetup |= 1<<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[qnum];
 }
@@ -1042,30 +1054,49 @@ void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx)
         for (;;) {
                 spin_lock_bh(&txq->axq_lock);
 
-                if (list_empty(&txq->axq_q)) {
-                        txq->axq_link = NULL;
-                        spin_unlock_bh(&txq->axq_lock);
-                        break;
-                }
-
-                bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
+                if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                        if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
+                                txq->txq_headidx = txq->txq_tailidx = 0;
+                                spin_unlock_bh(&txq->axq_lock);
+                                break;
+                        } else {
+                                bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
+                                                      struct ath_buf, list);
+                        }
+                } else {
+                        if (list_empty(&txq->axq_q)) {
+                                txq->axq_link = NULL;
+                                spin_unlock_bh(&txq->axq_lock);
+                                break;
+                        }
+                        bf = list_first_entry(&txq->axq_q, struct ath_buf,
+                                              list);
 
-                if (bf->bf_stale) {
-                        list_del(&bf->list);
-                        spin_unlock_bh(&txq->axq_lock);
+                        if (bf->bf_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;
+                                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_tx_aborted = true;
 
-                /* remove ath_buf's of the same mpdu from txq */
-                list_cut_position(&bf_head, &txq->axq_q, &lastbf->list);
+                if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                        list_cut_position(&bf_head,
+                                          &txq->txq_fifo[txq->txq_tailidx],
+                                          &lastbf->list);
+                        INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
+                } else {
+                        /* 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);
@@ -1088,6 +1119,27 @@ void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx)
                         spin_unlock_bh(&txq->axq_lock);
                 }
         }
+
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                spin_lock_bh(&txq->axq_lock);
+                while (!list_empty(&txq->txq_fifo_pending)) {
+                        bf = list_first_entry(&txq->txq_fifo_pending,
+                                              struct ath_buf, list);
+                        list_cut_position(&bf_head,
+                                          &txq->txq_fifo_pending,
+                                          &bf->bf_lastbf->list);
+                        spin_unlock_bh(&txq->axq_lock);
+
+                        if (bf_isampdu(bf))
+                                ath_tx_complete_aggr(sc, txq, bf, &bf_head,
+                                                     &ts, 0);
+                        else
+                                ath_tx_complete_buf(sc, bf, txq, &bf_head,
+                                                    &ts, 0, 0);
+                        spin_lock_bh(&txq->axq_lock);
+                }
+                spin_unlock_bh(&txq->axq_lock);
+        }
 }
 
 void ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
@@ -1225,25 +1277,47 @@ static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
 
         bf = list_first_entry(head, struct ath_buf, list);
 
-        list_splice_tail_init(head, &txq->axq_q);
-        txq->axq_depth++;
-
         ath_print(common, ATH_DBG_QUEUE,
                   "qnum: %d, txq depth: %d\n", txq->axq_qnum, txq->axq_depth);
 
-        if (txq->axq_link == NULL) {
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                if (txq->axq_depth >= ATH_TXFIFO_DEPTH) {
+                        list_splice_tail_init(head, &txq->txq_fifo_pending);
+                        return;
+                }
+                if (!list_empty(&txq->txq_fifo[txq->txq_headidx]))
+                        ath_print(common, ATH_DBG_XMIT,
+                                  "Initializing tx fifo %d which "
+                                  "is non-empty\n",
+                                  txq->txq_headidx);
+                INIT_LIST_HEAD(&txq->txq_fifo[txq->txq_headidx]);
+                list_splice_init(head, &txq->txq_fifo[txq->txq_headidx]);
+                INCR(txq->txq_headidx, ATH_TXFIFO_DEPTH);
                 ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
                 ath_print(common, 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;
-                ath_print(common, ATH_DBG_XMIT, "link[%u] (%p)=%llx (%p)\n",
-                          txq->axq_qnum, txq->axq_link,
-                          ito64(bf->bf_daddr), bf->bf_desc);
+                list_splice_tail_init(head, &txq->axq_q);
+
+                if (txq->axq_link == NULL) {
+                        ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
+                        ath_print(common, 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;
+                        ath_print(common, ATH_DBG_XMIT,
+                                        "link[%u] (%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);
         }
-        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 struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
@@ -2140,6 +2214,80 @@ void ath_tx_tasklet(struct ath_softc *sc)
         }
 }
 
+void ath_tx_edma_tasklet(struct ath_softc *sc)
+{
+        struct ath_tx_status txs;
+        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_txq *txq;
+        struct ath_buf *bf, *lastbf;
+        struct list_head bf_head;
+        int status;
+        int txok;
+
+        for (;;) {
+                status = ath9k_hw_txprocdesc(ah, NULL, (void *)&txs);
+                if (status == -EINPROGRESS)
+                        break;
+                if (status == -EIO) {
+                        ath_print(common, ATH_DBG_XMIT,
+                                  "Error processing tx status\n");
+                        break;
+                }
+
+                /* Skip beacon completions */
+                if (txs.qid == sc->beacon.beaconq)
+                        continue;
+
+                txq = &sc->tx.txq[txs.qid];
+
+                spin_lock_bh(&txq->axq_lock);
+                if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
+                        spin_unlock_bh(&txq->axq_lock);
+                        return;
+                }
+
+                bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
+                                      struct ath_buf, list);
+                lastbf = bf->bf_lastbf;
+
+                INIT_LIST_HEAD(&bf_head);
+                list_cut_position(&bf_head, &txq->txq_fifo[txq->txq_tailidx],
+                                  &lastbf->list);
+                INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
+                txq->axq_depth--;
+                txq->axq_tx_inprogress = false;
+                spin_unlock_bh(&txq->axq_lock);
+
+                txok = !(txs.ts_status & ATH9K_TXERR_MASK);
+
+                if (!bf_isampdu(bf)) {
+                        bf->bf_retries = txs.ts_longretry;
+                        if (txs.ts_status & ATH9K_TXERR_XRETRY)
+                                bf->bf_state.bf_type |= BUF_XRETRY;
+                        ath_tx_rc_status(bf, &txs, 0, txok, true);
+                }
+
+                if (bf_isampdu(bf))
+                        ath_tx_complete_aggr(sc, txq, bf, &bf_head, &txs, txok);
+                else
+                        ath_tx_complete_buf(sc, bf, txq, &bf_head,
+                                            &txs, txok, 0);
+
+                spin_lock_bh(&txq->axq_lock);
+                if (!list_empty(&txq->txq_fifo_pending)) {
+                        INIT_LIST_HEAD(&bf_head);
+                        bf = list_first_entry(&txq->txq_fifo_pending,
+                                struct ath_buf, list);
+                        list_cut_position(&bf_head, &txq->txq_fifo_pending,
+                                &bf->bf_lastbf->list);
+                        ath_tx_txqaddbuf(sc, txq, &bf_head);
+                } else if (sc->sc_flags & SC_OP_TXAGGR)
+                        ath_txq_schedule(sc, txq);
+                spin_unlock_bh(&txq->axq_lock);
+        }
+}
+
 /*****************/
 /* Init, Cleanup */
 /*****************/