ath9k: Add Rx EDMA support

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

5 files changed, 459 insertions, 113 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ar9003_mac.c b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
index f28adb23ac8..b229597e54c 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_mac.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_mac.c
@@ -72,6 +72,9 @@ int ath9k_hw_process_rxdesc_edma(struct ath_hw *ah, struct ath_rx_status *rxs,
         if ((rxsp->ds_info & (AR_TxRxDesc | AR_CtrlStat)) != 0)
                 return -EINPROGRESS;
 
+        if (!rxs)
+                return 0;
+
         rxs->rs_status = 0;
         rxs->rs_flags =  0;
 
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index bdcd257ca7a..a11d830d76a 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -223,6 +223,12 @@ struct ath_tx {
         struct ath_descdma txdma;
 };
 
+struct ath_rx_edma {
+        struct sk_buff_head rx_fifo;
+        struct sk_buff_head rx_buffers;
+        u32 rx_fifo_hwsize;
+};
+
 struct ath_rx {
         u8 defant;
         u8 rxotherant;
@@ -232,6 +238,8 @@ struct ath_rx {
         spinlock_t rxbuflock;
         struct list_head rxbuf;
         struct ath_descdma rxdma;
+        struct ath_buf *rx_bufptr;
+        struct ath_rx_edma rx_edma[ATH9K_RX_QUEUE_MAX];
 };
 
 int ath_startrecv(struct ath_softc *sc);
@@ -240,7 +248,7 @@ void ath_flushrecv(struct ath_softc *sc);
 u32 ath_calcrxfilter(struct ath_softc *sc);
 int ath_rx_init(struct ath_softc *sc, int nbufs);
 void ath_rx_cleanup(struct ath_softc *sc);
-int ath_rx_tasklet(struct ath_softc *sc, int flush);
+int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp);
 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype);
 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq);
 int ath_tx_setup(struct ath_softc *sc, int haltype);
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index c02f46e4a9b..1eceda22ae5 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -246,6 +246,8 @@ struct ath9k_ops_config {
 enum ath9k_int {
         ATH9K_INT_RX = 0x00000001,
         ATH9K_INT_RXDESC = 0x00000002,
+        ATH9K_INT_RXHP = 0x00000001,
+        ATH9K_INT_RXLP = 0x00000002,
         ATH9K_INT_RXNOFRM = 0x00000008,
         ATH9K_INT_RXEOL = 0x00000010,
         ATH9K_INT_RXORN = 0x00000020,
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 494456cd1da..92f6fdc3007 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -401,6 +401,7 @@ void ath9k_tasklet(unsigned long data)
         struct ath_common *common = ath9k_hw_common(ah);
 
         u32 status = sc->intrstatus;
+        u32 rxmask;
 
         ath9k_ps_wakeup(sc);
 
@@ -410,9 +411,21 @@ void ath9k_tasklet(unsigned long data)
                 return;
         }
 
-        if (status & (ATH9K_INT_RX | ATH9K_INT_RXEOL | ATH9K_INT_RXORN)) {
+        if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
+                rxmask = (ATH9K_INT_RXHP | ATH9K_INT_RXLP | ATH9K_INT_RXEOL |
+                          ATH9K_INT_RXORN);
+        else
+                rxmask = (ATH9K_INT_RX | ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
+
+        if (status & rxmask) {
                 spin_lock_bh(&sc->rx.rxflushlock);
-                ath_rx_tasklet(sc, 0);
+
+                /* Check for high priority Rx first */
+                if ((ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
+                    (status & ATH9K_INT_RXHP))
+                        ath_rx_tasklet(sc, 0, true);
+
+                ath_rx_tasklet(sc, 0, false);
                 spin_unlock_bh(&sc->rx.rxflushlock);
         }
 
@@ -445,6 +458,8 @@ irqreturn_t ath_isr(int irq, void *dev)
                 ATH9K_INT_RXORN |               \
                 ATH9K_INT_RXEOL |               \
                 ATH9K_INT_RX |                  \
+                ATH9K_INT_RXLP |                \
+                ATH9K_INT_RXHP |                \
                 ATH9K_INT_TX |                  \
                 ATH9K_INT_BMISS |               \
                 ATH9K_INT_CST |                 \
@@ -496,7 +511,8 @@ irqreturn_t ath_isr(int irq, void *dev)
          * If a FATAL or RXORN interrupt is received, we have to reset the
          * chip immediately.
          */
-        if (status & (ATH9K_INT_FATAL | ATH9K_INT_RXORN))
+        if ((status & ATH9K_INT_FATAL) || ((status & ATH9K_INT_RXORN) &&
+            !(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)))
                 goto chip_reset;
 
         if (status & ATH9K_INT_SWBA)
@@ -505,6 +521,13 @@ irqreturn_t ath_isr(int irq, void *dev)
         if (status & ATH9K_INT_TXURN)
                 ath9k_hw_updatetxtriglevel(ah, true);
 
+        if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                if (status & ATH9K_INT_RXEOL) {
+                        ah->imask &= ~(ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
+                        ath9k_hw_set_interrupts(ah, ah->imask);
+                }
+        }
+
         if (status & ATH9K_INT_MIB) {
                 /*
                  * Disable interrupts until we service the MIB
@@ -1162,9 +1185,14 @@ static int ath9k_start(struct ieee80211_hw *hw)
         }
 
         /* Setup our intr mask. */
-        ah->imask = ATH9K_INT_RX | ATH9K_INT_TX
-                | ATH9K_INT_RXEOL | ATH9K_INT_RXORN
-                | ATH9K_INT_FATAL | ATH9K_INT_GLOBAL;
+        ah->imask = ATH9K_INT_TX | ATH9K_INT_RXEOL |
+                    ATH9K_INT_RXORN | ATH9K_INT_FATAL |
+                    ATH9K_INT_GLOBAL;
+
+        if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
+                ah->imask |= ATH9K_INT_RXHP | ATH9K_INT_RXLP;
+        else
+                ah->imask |= ATH9K_INT_RX;
 
         if (ah->caps.hw_caps & ATH9K_HW_CAP_GTT)
                 ah->imask |= ATH9K_INT_GTT;
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index 94560e2fe37..ffb599c4918 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -16,6 +16,8 @@
 
 #include "ath9k.h"
 
+#define SKB_CB_ATHBUF(__skb)    (*((struct ath_buf **)__skb->cb))
+
 static struct ieee80211_hw * ath_get_virt_hw(struct ath_softc *sc,
                                              struct ieee80211_hdr *hdr)
 {
@@ -115,56 +117,246 @@ static void ath_opmode_init(struct ath_softc *sc)
         ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
 }
 
-int ath_rx_init(struct ath_softc *sc, int nbufs)
+static bool ath_rx_edma_buf_link(struct ath_softc *sc,
+                                 enum ath9k_rx_qtype qtype)
 {
-        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_rx_edma *rx_edma;
         struct sk_buff *skb;
         struct ath_buf *bf;
-        int error = 0;
 
-        spin_lock_init(&sc->rx.rxflushlock);
-        sc->sc_flags &= ~SC_OP_RXFLUSH;
-        spin_lock_init(&sc->rx.rxbuflock);
+        rx_edma = &sc->rx.rx_edma[qtype];
+        if (skb_queue_len(&rx_edma->rx_fifo) >= rx_edma->rx_fifo_hwsize)
+                return false;
 
-        common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
-                                     min(common->cachelsz, (u16)64));
+        bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
+        list_del_init(&bf->list);
 
-        ath_print(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
-                  common->cachelsz, common->rx_bufsize);
+        skb = bf->bf_mpdu;
+
+        ATH_RXBUF_RESET(bf);
+        memset(skb->data, 0, ah->caps.rx_status_len);
+        dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
+                                ah->caps.rx_status_len, DMA_TO_DEVICE);
 
-        /* Initialize rx descriptors */
+        SKB_CB_ATHBUF(skb) = bf;
+        ath9k_hw_addrxbuf_edma(ah, bf->bf_buf_addr, qtype);
+        skb_queue_tail(&rx_edma->rx_fifo, skb);
 
-        error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
-                                  "rx", nbufs, 1);
-        if (error != 0) {
-                ath_print(common, ATH_DBG_FATAL,
-                          "failed to allocate rx descriptors: %d\n", error);
-                goto err;
+        return true;
+}
+
+static void ath_rx_addbuffer_edma(struct ath_softc *sc,
+                                  enum ath9k_rx_qtype qtype, int size)
+{
+        struct ath_rx_edma *rx_edma;
+        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+        u32 nbuf = 0;
+
+        rx_edma = &sc->rx.rx_edma[qtype];
+        if (list_empty(&sc->rx.rxbuf)) {
+                ath_print(common, ATH_DBG_QUEUE, "No free rx buf available\n");
+                return;
         }
 
+        while (!list_empty(&sc->rx.rxbuf)) {
+                nbuf++;
+
+                if (!ath_rx_edma_buf_link(sc, qtype))
+                        break;
+
+                if (nbuf >= size)
+                        break;
+        }
+}
+
+static void ath_rx_remove_buffer(struct ath_softc *sc,
+                                 enum ath9k_rx_qtype qtype)
+{
+        struct ath_buf *bf;
+        struct ath_rx_edma *rx_edma;
+        struct sk_buff *skb;
+
+        rx_edma = &sc->rx.rx_edma[qtype];
+
+        while ((skb = skb_dequeue(&rx_edma->rx_fifo)) != NULL) {
+                bf = SKB_CB_ATHBUF(skb);
+                BUG_ON(!bf);
+                list_add_tail(&bf->list, &sc->rx.rxbuf);
+        }
+}
+
+static void ath_rx_edma_cleanup(struct ath_softc *sc)
+{
+        struct ath_buf *bf;
+
+        ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
+        ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
+
         list_for_each_entry(bf, &sc->rx.rxbuf, list) {
+                if (bf->bf_mpdu)
+                        dev_kfree_skb_any(bf->bf_mpdu);
+        }
+
+        INIT_LIST_HEAD(&sc->rx.rxbuf);
+
+        kfree(sc->rx.rx_bufptr);
+        sc->rx.rx_bufptr = NULL;
+}
+
+static void ath_rx_edma_init_queue(struct ath_rx_edma *rx_edma, int size)
+{
+        skb_queue_head_init(&rx_edma->rx_fifo);
+        skb_queue_head_init(&rx_edma->rx_buffers);
+        rx_edma->rx_fifo_hwsize = size;
+}
+
+static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)
+{
+        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+        struct ath_hw *ah = sc->sc_ah;
+        struct sk_buff *skb;
+        struct ath_buf *bf;
+        int error = 0, i;
+        u32 size;
+
+
+        common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN +
+                                     ah->caps.rx_status_len,
+                                     min(common->cachelsz, (u16)64));
+
+        ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -
+                                    ah->caps.rx_status_len);
+
+        ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_LP],
+                               ah->caps.rx_lp_qdepth);
+        ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_HP],
+                               ah->caps.rx_hp_qdepth);
+
+        size = sizeof(struct ath_buf) * nbufs;
+        bf = kzalloc(size, GFP_KERNEL);
+        if (!bf)
+                return -ENOMEM;
+
+        INIT_LIST_HEAD(&sc->rx.rxbuf);
+        sc->rx.rx_bufptr = bf;
+
+        for (i = 0; i < nbufs; i++, bf++) {
                 skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);
-                if (skb == NULL) {
+                if (!skb) {
                         error = -ENOMEM;
-                        goto err;
+                        goto rx_init_fail;
                 }
 
+                memset(skb->data, 0, common->rx_bufsize);
                 bf->bf_mpdu = skb;
+
                 bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
                                                  common->rx_bufsize,
-                                                 DMA_FROM_DEVICE);
+                                                 DMA_BIDIRECTIONAL);
                 if (unlikely(dma_mapping_error(sc->dev,
-                                               bf->bf_buf_addr))) {
-                        dev_kfree_skb_any(skb);
-                        bf->bf_mpdu = NULL;
+                                                bf->bf_buf_addr))) {
+                                dev_kfree_skb_any(skb);
+                                bf->bf_mpdu = NULL;
+                                ath_print(common, ATH_DBG_FATAL,
+                                        "dma_mapping_error() on RX init\n");
+                                error = -ENOMEM;
+                                goto rx_init_fail;
+                }
+
+                list_add_tail(&bf->list, &sc->rx.rxbuf);
+        }
+
+        return 0;
+
+rx_init_fail:
+        ath_rx_edma_cleanup(sc);
+        return error;
+}
+
+static void ath_edma_start_recv(struct ath_softc *sc)
+{
+        spin_lock_bh(&sc->rx.rxbuflock);
+
+        ath9k_hw_rxena(sc->sc_ah);
+
+        ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP,
+                              sc->rx.rx_edma[ATH9K_RX_QUEUE_HP].rx_fifo_hwsize);
+
+        ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP,
+                              sc->rx.rx_edma[ATH9K_RX_QUEUE_LP].rx_fifo_hwsize);
+
+        spin_unlock_bh(&sc->rx.rxbuflock);
+
+        ath_opmode_init(sc);
+
+        ath9k_hw_startpcureceive(sc->sc_ah);
+}
+
+static void ath_edma_stop_recv(struct ath_softc *sc)
+{
+        spin_lock_bh(&sc->rx.rxbuflock);
+        ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
+        ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
+        spin_unlock_bh(&sc->rx.rxbuflock);
+}
+
+int ath_rx_init(struct ath_softc *sc, int nbufs)
+{
+        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+        struct sk_buff *skb;
+        struct ath_buf *bf;
+        int error = 0;
+
+        spin_lock_init(&sc->rx.rxflushlock);
+        sc->sc_flags &= ~SC_OP_RXFLUSH;
+        spin_lock_init(&sc->rx.rxbuflock);
+
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                return ath_rx_edma_init(sc, nbufs);
+        } else {
+                common->rx_bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
+                                min(common->cachelsz, (u16)64));
+
+                ath_print(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
+                                common->cachelsz, common->rx_bufsize);
+
+                /* Initialize rx descriptors */
+
+                error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
+                                "rx", nbufs, 1);
+                if (error != 0) {
                         ath_print(common, ATH_DBG_FATAL,
-                                  "dma_mapping_error() on RX init\n");
-                        error = -ENOMEM;
+                                  "failed to allocate rx descriptors: %d\n",
+                                  error);
                         goto err;
                 }
-                bf->bf_dmacontext = bf->bf_buf_addr;
+
+                list_for_each_entry(bf, &sc->rx.rxbuf, list) {
+                        skb = ath_rxbuf_alloc(common, common->rx_bufsize,
+                                              GFP_KERNEL);
+                        if (skb == NULL) {
+                                error = -ENOMEM;
+                                goto err;
+                        }
+
+                        bf->bf_mpdu = skb;
+                        bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
+                                        common->rx_bufsize,
+                                        DMA_FROM_DEVICE);
+                        if (unlikely(dma_mapping_error(sc->dev,
+                                                        bf->bf_buf_addr))) {
+                                dev_kfree_skb_any(skb);
+                                bf->bf_mpdu = NULL;
+                                ath_print(common, ATH_DBG_FATAL,
+                                          "dma_mapping_error() on RX init\n");
+                                error = -ENOMEM;
+                                goto err;
+                        }
+                        bf->bf_dmacontext = bf->bf_buf_addr;
+                }
+                sc->rx.rxlink = NULL;
         }
-        sc->rx.rxlink = NULL;
 
 err:
         if (error)
@@ -180,17 +372,23 @@ void ath_rx_cleanup(struct ath_softc *sc)
         struct sk_buff *skb;
         struct ath_buf *bf;
 
-        list_for_each_entry(bf, &sc->rx.rxbuf, list) {
-                skb = bf->bf_mpdu;
-                if (skb) {
-                        dma_unmap_single(sc->dev, bf->bf_buf_addr,
-                                         common->rx_bufsize, DMA_FROM_DEVICE);
-                        dev_kfree_skb(skb);
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                ath_rx_edma_cleanup(sc);
+                return;
+        } else {
+                list_for_each_entry(bf, &sc->rx.rxbuf, list) {
+                        skb = bf->bf_mpdu;
+                        if (skb) {
+                                dma_unmap_single(sc->dev, bf->bf_buf_addr,
+                                                common->rx_bufsize,
+                                                DMA_FROM_DEVICE);
+                                dev_kfree_skb(skb);
+                        }
                 }
-        }
 
-        if (sc->rx.rxdma.dd_desc_len != 0)
-                ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
+                if (sc->rx.rxdma.dd_desc_len != 0)
+                        ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
+        }
 }
 
 /*
@@ -273,6 +471,11 @@ int ath_startrecv(struct ath_softc *sc)
         struct ath_hw *ah = sc->sc_ah;
         struct ath_buf *bf, *tbf;
 
+        if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
+                ath_edma_start_recv(sc);
+                return 0;
+        }
+
         spin_lock_bh(&sc->rx.rxbuflock);
         if (list_empty(&sc->rx.rxbuf))
                 goto start_recv;
@@ -306,7 +509,11 @@ bool ath_stoprecv(struct ath_softc *sc)
         ath9k_hw_stoppcurecv(ah);
         ath9k_hw_setrxfilter(ah, 0);
         stopped = ath9k_hw_stopdmarecv(ah);
-        sc->rx.rxlink = NULL;
+
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
+                ath_edma_stop_recv(sc);
+        else
+                sc->rx.rxlink = NULL;
 
         return stopped;
 }
@@ -315,7 +522,9 @@ void ath_flushrecv(struct ath_softc *sc)
 {
         spin_lock_bh(&sc->rx.rxflushlock);
         sc->sc_flags |= SC_OP_RXFLUSH;
-        ath_rx_tasklet(sc, 1);
+        if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
+                ath_rx_tasklet(sc, 1, true);
+        ath_rx_tasklet(sc, 1, false);
         sc->sc_flags &= ~SC_OP_RXFLUSH;
         spin_unlock_bh(&sc->rx.rxflushlock);
 }
@@ -469,14 +678,147 @@ static void ath_rx_send_to_mac80211(struct ieee80211_hw *hw,
                 ieee80211_rx(hw, skb);
 }
 
-int ath_rx_tasklet(struct ath_softc *sc, int flush)
+static bool ath_edma_get_buffers(struct ath_softc *sc,
+                                 enum ath9k_rx_qtype qtype)
 {
-#define PA2DESC(_sc, _pa)                                               \
-        ((struct ath_desc *)((caddr_t)(_sc)->rx.rxdma.dd_desc +         \
-                             ((_pa) - (_sc)->rx.rxdma.dd_desc_paddr)))
+        struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_common *common = ath9k_hw_common(ah);
+        struct sk_buff *skb;
+        struct ath_buf *bf;
+        int ret;
+
+        skb = skb_peek(&rx_edma->rx_fifo);
+        if (!skb)
+                return false;
+
+        bf = SKB_CB_ATHBUF(skb);
+        BUG_ON(!bf);
+
+        dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
+                                common->rx_bufsize, DMA_FROM_DEVICE);
+
+        ret = ath9k_hw_process_rxdesc_edma(ah, NULL, skb->data);
+        if (ret == -EINPROGRESS)
+                return false;
+
+        __skb_unlink(skb, &rx_edma->rx_fifo);
+        if (ret == -EINVAL) {
+                /* corrupt descriptor, skip this one and the following one */
+                list_add_tail(&bf->list, &sc->rx.rxbuf);
+                ath_rx_edma_buf_link(sc, qtype);
+                skb = skb_peek(&rx_edma->rx_fifo);
+                if (!skb)
+                        return true;
+
+                bf = SKB_CB_ATHBUF(skb);
+                BUG_ON(!bf);
+
+                __skb_unlink(skb, &rx_edma->rx_fifo);
+                list_add_tail(&bf->list, &sc->rx.rxbuf);
+                ath_rx_edma_buf_link(sc, qtype);
+        }
+        skb_queue_tail(&rx_edma->rx_buffers, skb);
+
+        return true;
+}
 
+static struct ath_buf *ath_edma_get_next_rx_buf(struct ath_softc *sc,
+                                                struct ath_rx_status *rs,
+                                                enum ath9k_rx_qtype qtype)
+{
+        struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
+        struct sk_buff *skb;
         struct ath_buf *bf;
+
+        while (ath_edma_get_buffers(sc, qtype));
+        skb = __skb_dequeue(&rx_edma->rx_buffers);
+        if (!skb)
+                return NULL;
+
+        bf = SKB_CB_ATHBUF(skb);
+        ath9k_hw_process_rxdesc_edma(sc->sc_ah, rs, skb->data);
+        return bf;
+}
+
+static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc,
+                                           struct ath_rx_status *rs)
+{
+        struct ath_hw *ah = sc->sc_ah;
+        struct ath_common *common = ath9k_hw_common(ah);
         struct ath_desc *ds;
+        struct ath_buf *bf;
+        int ret;
+
+        if (list_empty(&sc->rx.rxbuf)) {
+                sc->rx.rxlink = NULL;
+                return NULL;
+        }
+
+        bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
+        ds = bf->bf_desc;
+
+        /*
+         * Must provide the virtual address of the current
+         * descriptor, the physical address, and the virtual
+         * address of the next descriptor in the h/w chain.
+         * This allows the HAL to look ahead to see if the
+         * hardware is done with a descriptor by checking the
+         * done bit in the following descriptor and the address
+         * of the current descriptor the DMA engine is working
+         * on.  All this is necessary because of our use of
+         * a self-linked list to avoid rx overruns.
+         */
+        ret = ath9k_hw_rxprocdesc(ah, ds, rs, 0);
+        if (ret == -EINPROGRESS) {
+                struct ath_rx_status trs;
+                struct ath_buf *tbf;
+                struct ath_desc *tds;
+
+                memset(&trs, 0, sizeof(trs));
+                if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
+                        sc->rx.rxlink = NULL;
+                        return NULL;
+                }
+
+                tbf = list_entry(bf->list.next, struct ath_buf, list);
+
+                /*
+                 * On some hardware the descriptor status words could
+                 * get corrupted, including the done bit. Because of
+                 * this, check if the next descriptor's done bit is
+                 * set or not.
+                 *
+                 * If the next descriptor's done bit is set, the current
+                 * descriptor has been corrupted. Force s/w to discard
+                 * this descriptor and continue...
+                 */
+
+                tds = tbf->bf_desc;
+                ret = ath9k_hw_rxprocdesc(ah, tds, &trs, 0);
+                if (ret == -EINPROGRESS)
+                        return NULL;
+        }
+
+        if (!bf->bf_mpdu)
+                return bf;
+
+        /*
+         * Synchronize the DMA transfer with CPU before
+         * 1. accessing the frame
+         * 2. requeueing the same buffer to h/w
+         */
+        dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
+                        common->rx_bufsize,
+                        DMA_FROM_DEVICE);
+
+        return bf;
+}
+
+
+int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
+{
+        struct ath_buf *bf;
         struct sk_buff *skb = NULL, *requeue_skb;
         struct ieee80211_rx_status *rxs;
         struct ath_hw *ah = sc->sc_ah;
@@ -491,7 +833,16 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
         int retval;
         bool decrypt_error = false;
         struct ath_rx_status rs;
+        enum ath9k_rx_qtype qtype;
+        bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
+        int dma_type;
 
+        if (edma)
+                dma_type = DMA_FROM_DEVICE;
+        else
+                dma_type = DMA_BIDIRECTIONAL;
+
+        qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
         spin_lock_bh(&sc->rx.rxbuflock);
 
         do {
@@ -499,71 +850,19 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                 if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
                         break;
 
-                if (list_empty(&sc->rx.rxbuf)) {
-                        sc->rx.rxlink = NULL;
-                        break;
-                }
-
-                bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
-                ds = bf->bf_desc;
-
-                /*
-                 * Must provide the virtual address of the current
-                 * descriptor, the physical address, and the virtual
-                 * address of the next descriptor in the h/w chain.
-                 * This allows the HAL to look ahead to see if the
-                 * hardware is done with a descriptor by checking the
-                 * done bit in the following descriptor and the address
-                 * of the current descriptor the DMA engine is working
-                 * on.  All this is necessary because of our use of
-                 * a self-linked list to avoid rx overruns.
-                 */
                 memset(&rs, 0, sizeof(rs));
-                retval = ath9k_hw_rxprocdesc(ah, ds, &rs, 0);
-                if (retval == -EINPROGRESS) {
-                        struct ath_rx_status trs;
-                        struct ath_buf *tbf;
-                        struct ath_desc *tds;
-
-                        memset(&trs, 0, sizeof(trs));
-                        if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
-                                sc->rx.rxlink = NULL;
-                                break;
-                        }
+                if (edma)
+                        bf = ath_edma_get_next_rx_buf(sc, &rs, qtype);
+                else
+                        bf = ath_get_next_rx_buf(sc, &rs);
 
-                        tbf = list_entry(bf->list.next, struct ath_buf, list);
-
-                        /*
-                         * On some hardware the descriptor status words could
-                         * get corrupted, including the done bit. Because of
-                         * this, check if the next descriptor's done bit is
-                         * set or not.
-                         *
-                         * If the next descriptor's done bit is set, the current
-                         * descriptor has been corrupted. Force s/w to discard
-                         * this descriptor and continue...
-                         */
-
-                        tds = tbf->bf_desc;
-                        retval = ath9k_hw_rxprocdesc(ah, tds, &trs, 0);
-                        if (retval == -EINPROGRESS) {
-                                break;
-                        }
-                }
+                if (!bf)
+                        break;
 
                 skb = bf->bf_mpdu;
                 if (!skb)
                         continue;
 
-                /*
-                 * Synchronize the DMA transfer with CPU before
-                 * 1. accessing the frame
-                 * 2. requeueing the same buffer to h/w
-                 */
-                dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
-                                common->rx_bufsize,
-                                DMA_FROM_DEVICE);
-
                 hdr = (struct ieee80211_hdr *) skb->data;
                 rxs =  IEEE80211_SKB_RXCB(skb);
 
@@ -597,9 +896,11 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                 /* Unmap the frame */
                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
                                  common->rx_bufsize,
-                                 DMA_FROM_DEVICE);
+                                 dma_type);
 
-                skb_put(skb, rs.rs_datalen);
+                skb_put(skb, rs.rs_datalen + ah->caps.rx_status_len);
+                if (ah->caps.rx_status_len)
+                        skb_pull(skb, ah->caps.rx_status_len);
 
                 ath9k_cmn_rx_skb_postprocess(common, skb, &rs,
                                              rxs, decrypt_error);
@@ -608,7 +909,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                 bf->bf_mpdu = requeue_skb;
                 bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
                                                  common->rx_bufsize,
-                                                 DMA_FROM_DEVICE);
+                                                 dma_type);
                 if (unlikely(dma_mapping_error(sc->dev,
                           bf->bf_buf_addr))) {
                         dev_kfree_skb_any(requeue_skb);
@@ -639,12 +940,16 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                 ath_rx_send_to_mac80211(hw, sc, skb, rxs);
 
 requeue:
-                list_move_tail(&bf->list, &sc->rx.rxbuf);
-                ath_rx_buf_link(sc, bf);
+                if (edma) {
+                        list_add_tail(&bf->list, &sc->rx.rxbuf);
+                        ath_rx_edma_buf_link(sc, qtype);
+                } else {
+                        list_move_tail(&bf->list, &sc->rx.rxbuf);
+                        ath_rx_buf_link(sc, bf);
+                }
         } while (1);
 
         spin_unlock_bh(&sc->rx.rxbuflock);
 
         return 0;
-#undef PA2DESC
 }