ath9k: Revamp RX handling

Remove a lot of old, crufty code and make
RX status reporting a bit sane and clean.

Do not do anything to the RX skb before unmapping.
So in ath_rx_tasklet(), move the skb_put() after PCI unmap.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 206 insertions, 369 deletions

diff --git a/drivers/net/wireless/ath9k/recv.c b/drivers/net/wireless/ath9k/recv.c
index 2d72ac19fada..000e189e104a 100644
--- a/drivers/net/wireless/ath9k/recv.c
+++ b/drivers/net/wireless/ath9k/recv.c
@@ -14,10 +14,6 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/*
- * Implementation of receive path.
- */
-
 #include "core.h"
 
 /*
@@ -27,10 +23,7 @@
  * MAC acknowledges BA status as long as it copies frames to host
  * buffer (or rx fifo). This can incorrectly acknowledge packets
  * to a sender if last desc is self-linked.
- *
- * NOTE: Caller should hold the rxbuf lock.
  */
-
 static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
 {
         struct ath_hal *ah = sc->sc_ah;
@@ -40,19 +33,17 @@ static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
         ATH_RXBUF_RESET(bf);
 
         ds = bf->bf_desc;
-        ds->ds_link = 0;    /* link to null */
+        ds->ds_link = 0; /* link to null */
         ds->ds_data = bf->bf_buf_addr;
 
-        /* XXX For RADAR?
-         * virtual addr of the beginning of the buffer. */
+        /* virtual addr of the beginning of the buffer. */
         skb = bf->bf_mpdu;
         ASSERT(skb != NULL);
         ds->ds_vdata = skb->data;
 
         /* setup rx descriptors */
-        ath9k_hw_setuprxdesc(ah,
-                             ds,
-                             skb_tailroom(skb),   /* buffer size */
+        ath9k_hw_setuprxdesc(ah, ds,
+                             skb_tailroom(skb), /* buffer size */
                              0);
 
         if (sc->sc_rxlink == NULL)
@@ -64,8 +55,7 @@ static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
         ath9k_hw_rxena(ah);
 }
 
-static struct sk_buff *ath_rxbuf_alloc(struct ath_softc *sc,
-        u32 len)
+static struct sk_buff *ath_rxbuf_alloc(struct ath_softc *sc, u32 len)
 {
         struct sk_buff *skb;
         u32 off;
@@ -91,59 +81,154 @@ static struct sk_buff *ath_rxbuf_alloc(struct ath_softc *sc,
         return skb;
 }
 
-static void ath_rx_requeue(struct ath_softc *sc, struct sk_buff *skb)
+static void ath_rx_requeue(struct ath_softc *sc, struct ath_buf *bf)
 {
-        struct ath_buf *bf = ATH_RX_CONTEXT(skb)->ctx_rxbuf;
+        struct sk_buff *skb;
 
         ASSERT(bf != NULL);
 
-        spin_lock_bh(&sc->sc_rxbuflock);
-        if (bf->bf_status & ATH_BUFSTATUS_STALE) {
-                /*
-                 * This buffer is still held for hw acess.
-                 * Mark it as free to be re-queued it later.
-                 */
-                bf->bf_status |= ATH_BUFSTATUS_FREE;
-        } else {
-                /* XXX: we probably never enter here, remove after
-                 * verification */
-                list_add_tail(&bf->list, &sc->sc_rxbuf);
-                ath_rx_buf_link(sc, bf);
+        if (bf->bf_mpdu == NULL) {
+                skb = ath_rxbuf_alloc(sc, sc->sc_rxbufsize);
+                if (skb != NULL) {
+                        bf->bf_mpdu = skb;
+                        bf->bf_buf_addr = pci_map_single(sc->pdev, skb->data,
+                                                 skb_end_pointer(skb) - skb->head,
+                                                 PCI_DMA_FROMDEVICE);
+                        bf->bf_dmacontext = bf->bf_buf_addr;
+
+                }
         }
-        spin_unlock_bh(&sc->sc_rxbuflock);
+
+        list_move_tail(&bf->list, &sc->sc_rxbuf);
+        ath_rx_buf_link(sc, bf);
+}
+
+
+static int ath_rate2idx(struct ath_softc *sc, int rate)
+{
+        int i = 0, cur_band, n_rates;
+        struct ieee80211_hw *hw = sc->hw;
+
+        cur_band = hw->conf.channel->band;
+        n_rates = sc->sbands[cur_band].n_bitrates;
+
+        for (i = 0; i < n_rates; i++) {
+                if (sc->sbands[cur_band].bitrates[i].bitrate == rate)
+                        break;
+        }
+
+        /*
+         * NB:mac80211 validates rx rate index against the supported legacy rate
+         * index only (should be done against ht rates also), return the highest
+         * legacy rate index for rx rate which does not match any one of the
+         * supported basic and extended rates to make mac80211 happy.
+         * The following hack will be cleaned up once the issue with
+         * the rx rate index validation in mac80211 is fixed.
+         */
+        if (i == n_rates)
+                return n_rates - 1;
+
+        return i;
 }
 
 /*
- * The skb indicated to upper stack won't be returned to us.
- * So we have to allocate a new one and queue it by ourselves.
+ * For Decrypt or Demic errors, we only mark packet status here and always push
+ * up the frame up to let mac80211 handle the actual error case, be it no
+ * decryption key or real decryption error. This let us keep statistics there.
  */
-static int ath_rx_indicate(struct ath_softc *sc,
-                           struct sk_buff *skb,
-                           struct ath_recv_status *status,
-                           u16 keyix)
+static int ath_rx_prepare(struct sk_buff *skb, struct ath_desc *ds,
+                          struct ieee80211_rx_status *rx_status, bool *decrypt_error,
+                          struct ath_softc *sc)
 {
-        struct ath_buf *bf = ATH_RX_CONTEXT(skb)->ctx_rxbuf;
-        struct sk_buff *nskb;
-        int type;
-
-        /* indicate frame to the stack, which will free the old skb. */
-        type = _ath_rx_indicate(sc, skb, status, keyix);
-
-        /* allocate a new skb and queue it to for H/W processing */
-        nskb = ath_rxbuf_alloc(sc, sc->sc_rxbufsize);
-        if (nskb != NULL) {
-                bf->bf_mpdu = nskb;
-                bf->bf_buf_addr = pci_map_single(sc->pdev, nskb->data,
-                                         skb_end_pointer(nskb) - nskb->head,
-                                         PCI_DMA_FROMDEVICE);
-                bf->bf_dmacontext = bf->bf_buf_addr;
-                ATH_RX_CONTEXT(nskb)->ctx_rxbuf = bf;
+        struct ieee80211_hdr *hdr;
+        int ratekbps;
+        u8 ratecode;
+        __le16 fc;
+
+        hdr = (struct ieee80211_hdr *)skb->data;
+        fc = hdr->frame_control;
+        memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
+
+        if (ds->ds_rxstat.rs_more) {
+                /*
+                 * Frame spans multiple descriptors; this cannot happen yet
+                 * as we don't support jumbograms. If not in monitor mode,
+                 * discard the frame. Enable this if you want to see
+                 * error frames in Monitor mode.
+                 */
+                if (sc->sc_ah->ah_opmode != ATH9K_M_MONITOR)
+                        goto rx_next;
+        } else if (ds->ds_rxstat.rs_status != 0) {
+                if (ds->ds_rxstat.rs_status & ATH9K_RXERR_CRC)
+                        rx_status->flag |= RX_FLAG_FAILED_FCS_CRC;
+                if (ds->ds_rxstat.rs_status & ATH9K_RXERR_PHY)
+                        goto rx_next;
 
-                /* queue the new wbuf to H/W */
-                ath_rx_requeue(sc, nskb);
+                if (ds->ds_rxstat.rs_status & ATH9K_RXERR_DECRYPT) {
+                        *decrypt_error = true;
+                } else if (ds->ds_rxstat.rs_status & ATH9K_RXERR_MIC) {
+                        if (ieee80211_is_ctl(fc))
+                                /*
+                                 * Sometimes, we get invalid
+                                 * MIC failures on valid control frames.
+                                 * Remove these mic errors.
+                                 */
+                                ds->ds_rxstat.rs_status &= ~ATH9K_RXERR_MIC;
+                        else
+                                rx_status->flag |= RX_FLAG_MMIC_ERROR;
+                }
+                /*
+                 * Reject error frames with the exception of
+                 * decryption and MIC failures. For monitor mode,
+                 * we also ignore the CRC error.
+                 */
+                if (sc->sc_ah->ah_opmode == ATH9K_M_MONITOR) {
+                        if (ds->ds_rxstat.rs_status &
+                            ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
+                              ATH9K_RXERR_CRC))
+                                goto rx_next;
+                } else {
+                        if (ds->ds_rxstat.rs_status &
+                            ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
+                                goto rx_next;
+                        }
+                }
         }
 
-        return type;
+        ratecode = ds->ds_rxstat.rs_rate;
+        ratekbps = sc->sc_hwmap[ratecode].rateKbps;
+
+        /* HT rate */
+        if (ratecode & 0x80) {
+                if (ds->ds_rxstat.rs_flags & ATH9K_RX_2040)
+                        ratekbps = (ratekbps * 27) / 13;
+                if (ds->ds_rxstat.rs_flags & ATH9K_RX_GI)
+                        ratekbps = (ratekbps * 10) / 9;
+        }
+
+        rx_status->mactime = ath_extend_tsf(sc, ds->ds_rxstat.rs_tstamp);
+        rx_status->band = sc->hw->conf.channel->band;
+        rx_status->freq =  sc->hw->conf.channel->center_freq;
+        rx_status->noise = sc->sc_ani.sc_noise_floor;
+        rx_status->signal = rx_status->noise + ds->ds_rxstat.rs_rssi;
+        rx_status->rate_idx = ath_rate2idx(sc, (ratekbps / 100));
+        rx_status->antenna = ds->ds_rxstat.rs_antenna;
+
+        /* at 45 you will be able to use MCS 15 reliably. A more elaborate
+         * scheme can be used here but it requires tables of SNR/throughput for
+         * each possible mode used. */
+        rx_status->qual =  ds->ds_rxstat.rs_rssi * 100 / 45;
+
+        /* rssi can be more than 45 though, anything above that
+         * should be considered at 100% */
+        if (rx_status->qual > 100)
+                rx_status->qual = 100;
+
+        rx_status->flag |= RX_FLAG_TSFT;
+
+        return 1;
+rx_next:
+        return 0;
 }
 
 static void ath_opmode_init(struct ath_softc *sc)
@@ -185,12 +270,6 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
                 sc->sc_flags &= ~SC_OP_RXFLUSH;
                 spin_lock_init(&sc->sc_rxbuflock);
 
-                /*
-                 * Cisco's VPN software requires that drivers be able to
-                 * receive encapsulated frames that are larger than the MTU.
-                 * Since we can't be sure how large a frame we'll get, setup
-                 * to handle the larges on possible.
-                 */
                 sc->sc_rxbufsize = roundup(IEEE80211_MAX_MPDU_LEN,
                                            min(sc->sc_cachelsz,
                                                (u16)64));
@@ -209,8 +288,6 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
                         break;
                 }
 
-                /* Pre-allocate a wbuf for each rx buffer */
-
                 list_for_each_entry(bf, &sc->sc_rxbuf, list) {
                         skb = ath_rxbuf_alloc(sc, sc->sc_rxbufsize);
                         if (skb == NULL) {
@@ -223,7 +300,6 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
                                          skb_end_pointer(skb) - skb->head,
                                          PCI_DMA_FROMDEVICE);
                         bf->bf_dmacontext = bf->bf_buf_addr;
-                        ATH_RX_CONTEXT(skb)->ctx_rxbuf = bf;
                 }
                 sc->sc_rxlink = NULL;
 
@@ -235,8 +311,6 @@ int ath_rx_init(struct ath_softc *sc, int nbufs)
         return error;
 }
 
-/* Reclaim all rx queue resources */
-
 void ath_rx_cleanup(struct ath_softc *sc)
 {
         struct sk_buff *skb;
@@ -248,8 +322,6 @@ void ath_rx_cleanup(struct ath_softc *sc)
                         dev_kfree_skb(skb);
         }
 
-        /* cleanup rx descriptors */
-
         if (sc->sc_rxdma.dd_desc_len != 0)
                 ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
 }
@@ -297,20 +369,19 @@ u32 ath_calcrxfilter(struct ath_softc *sc)
         }
 
         if (sc->sc_ah->ah_opmode == ATH9K_M_STA ||
-                        sc->sc_ah->ah_opmode == ATH9K_M_IBSS)
+            sc->sc_ah->ah_opmode == ATH9K_M_IBSS)
                 rfilt |= ATH9K_RX_FILTER_BEACON;
 
         /* If in HOSTAP mode, want to enable reception of PSPOLL frames
            & beacon frames */
         if (sc->sc_ah->ah_opmode == ATH9K_M_HOSTAP)
                 rfilt |= (ATH9K_RX_FILTER_BEACON | ATH9K_RX_FILTER_PSPOLL);
+
         return rfilt;
 
 #undef RX_FILTER_PRESERVE
 }
 
-/* Enable the receive h/w following a reset. */
-
 int ath_startrecv(struct ath_softc *sc)
 {
         struct ath_hal *ah = sc->sc_ah;
@@ -322,21 +393,6 @@ int ath_startrecv(struct ath_softc *sc)
 
         sc->sc_rxlink = NULL;
         list_for_each_entry_safe(bf, tbf, &sc->sc_rxbuf, list) {
-                if (bf->bf_status & ATH_BUFSTATUS_STALE) {
-                        /* restarting h/w, no need for holding descriptors */
-                        bf->bf_status &= ~ATH_BUFSTATUS_STALE;
-                        /*
-                         * Upper layer may not be done with the frame yet so
-                         * we can't just re-queue it to hardware. Remove it
-                         * from h/w queue. It'll be re-queued when upper layer
-                         * returns the frame and ath_rx_requeue_mpdu is called.
-                         */
-                        if (!(bf->bf_status & ATH_BUFSTATUS_FREE)) {
-                                list_del(&bf->list);
-                                continue;
-                        }
-                }
-                /* chain descriptors */
                 ath_rx_buf_link(sc, bf);
         }
 
@@ -346,120 +402,69 @@ int ath_startrecv(struct ath_softc *sc)
 
         bf = list_first_entry(&sc->sc_rxbuf, struct ath_buf, list);
         ath9k_hw_putrxbuf(ah, bf->bf_daddr);
-        ath9k_hw_rxena(ah);      /* enable recv descriptors */
+        ath9k_hw_rxena(ah);
 
 start_recv:
         spin_unlock_bh(&sc->sc_rxbuflock);
-        ath_opmode_init(sc);        /* set filters, etc. */
-        ath9k_hw_startpcureceive(ah);   /* re-enable PCU/DMA engine */
+        ath_opmode_init(sc);
+        ath9k_hw_startpcureceive(ah);
+
         return 0;
 }
 
-/* Disable the receive h/w in preparation for a reset. */
-
 bool ath_stoprecv(struct ath_softc *sc)
 {
         struct ath_hal *ah = sc->sc_ah;
-        u64 tsf;
         bool stopped;
 
-        ath9k_hw_stoppcurecv(ah);       /* disable PCU */
-        ath9k_hw_setrxfilter(ah, 0);    /* clear recv filter */
-        stopped = ath9k_hw_stopdmarecv(ah);     /* disable DMA engine */
-        mdelay(3);                      /* 3ms is long enough for 1 frame */
-        tsf = ath9k_hw_gettsf64(ah);
-        sc->sc_rxlink = NULL;           /* just in case */
+        ath9k_hw_stoppcurecv(ah);
+        ath9k_hw_setrxfilter(ah, 0);
+        stopped = ath9k_hw_stopdmarecv(ah);
+        mdelay(3); /* 3ms is long enough for 1 frame */
+        sc->sc_rxlink = NULL;
+
         return stopped;
 }
 
-/* Flush receive queue */
-
 void ath_flushrecv(struct ath_softc *sc)
 {
-        /*
-         * ath_rx_tasklet may be used to handle rx interrupt and flush receive
-         * queue at the same time. Use a lock to serialize the access of rx
-         * queue.
-         * ath_rx_tasklet cannot hold the spinlock while indicating packets.
-         * Instead, do not claim the spinlock but check for a flush in
-         * progress (see references to sc_rxflush)
-         */
         spin_lock_bh(&sc->sc_rxflushlock);
         sc->sc_flags |= SC_OP_RXFLUSH;
-
         ath_rx_tasklet(sc, 1);
-
         sc->sc_flags &= ~SC_OP_RXFLUSH;
         spin_unlock_bh(&sc->sc_rxflushlock);
 }
 
-/* Process receive queue, as well as LED, etc. */
-
 int ath_rx_tasklet(struct ath_softc *sc, int flush)
 {
 #define PA2DESC(_sc, _pa)                                               \
         ((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc +         \
                              ((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
 
-        struct ath_buf *bf, *bf_held = NULL;
+        struct ath_buf *bf;
         struct ath_desc *ds;
-        struct ieee80211_hdr *hdr;
         struct sk_buff *skb = NULL;
-        struct ath_recv_status rx_status;
+        struct ieee80211_rx_status rx_status;
         struct ath_hal *ah = sc->sc_ah;
-        int type, rx_processed = 0;
-        u32 phyerr;
-        u8 chainreset = 0;
-        int retval;
-        __le16 fc;
+        struct ieee80211_hdr *hdr;
+        int hdrlen, padsize, retval;
+        bool decrypt_error = false;
+        u8 keyix;
+
+        spin_lock_bh(&sc->sc_rxbuflock);
 
         do {
                 /* If handling rx interrupt and flush is in progress => exit */
                 if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
                         break;
 
-                spin_lock_bh(&sc->sc_rxbuflock);
                 if (list_empty(&sc->sc_rxbuf)) {
                         sc->sc_rxlink = NULL;
-                        spin_unlock_bh(&sc->sc_rxbuflock);
                         break;
                 }
 
                 bf = list_first_entry(&sc->sc_rxbuf, struct ath_buf, list);
-
-                /*
-                 * There is a race condition that BH gets scheduled after sw
-                 * writes RxE 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.
-                 */
-                if (bf->bf_status & ATH_BUFSTATUS_STALE) {
-                        bf_held = bf;
-                        if (list_is_last(&bf_held->list, &sc->sc_rxbuf)) {
-                                /*
-                                 * The holding descriptor is the last
-                                 * descriptor in queue. It's safe to
-                                 * remove the last holding descriptor
-                                 * in BH context.
-                                 */
-                                list_del(&bf_held->list);
-                                bf_held->bf_status &= ~ATH_BUFSTATUS_STALE;
-                                sc->sc_rxlink = NULL;
-
-                                if (bf_held->bf_status & ATH_BUFSTATUS_FREE) {
-                                        list_add_tail(&bf_held->list,
-                                                &sc->sc_rxbuf);
-                                        ath_rx_buf_link(sc, bf_held);
-                                }
-                                spin_unlock_bh(&sc->sc_rxbuflock);
-                                break;
-                        }
-                        bf = list_entry(bf->list.next, struct ath_buf, list);
-                }
-
                 ds = bf->bf_desc;
-                ++rx_processed;
 
                 /*
                  * Must provide the virtual address of the current
@@ -472,8 +477,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                  * on.  All this is necessary because of our use of
                  * a self-linked list to avoid rx overruns.
                  */
-                retval = ath9k_hw_rxprocdesc(ah,
-                                             ds,
+                retval = ath9k_hw_rxprocdesc(ah, ds,
                                              bf->bf_daddr,
                                              PA2DESC(sc, ds->ds_link),
                                              0);
@@ -482,7 +486,7 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                         struct ath_desc *tds;
 
                         if (list_is_last(&bf->list, &sc->sc_rxbuf)) {
-                                spin_unlock_bh(&sc->sc_rxbuflock);
+                                sc->sc_rxlink = NULL;
                                 break;
                         }
 
@@ -500,215 +504,70 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                          */
 
                         tds = tbf->bf_desc;
-                        retval = ath9k_hw_rxprocdesc(ah,
-                                tds, tbf->bf_daddr,
-                                PA2DESC(sc, tds->ds_link), 0);
+                        retval = ath9k_hw_rxprocdesc(ah, tds, tbf->bf_daddr,
+                                             PA2DESC(sc, tds->ds_link), 0);
                         if (retval == -EINPROGRESS) {
-                                spin_unlock_bh(&sc->sc_rxbuflock);
                                 break;
                         }
                 }
 
-                /* XXX: we do not support frames spanning
-                 * multiple descriptors */
-                bf->bf_status |= ATH_BUFSTATUS_DONE;
-
                 skb = bf->bf_mpdu;
-                if (skb == NULL) {              /* XXX ??? can this happen */
-                        spin_unlock_bh(&sc->sc_rxbuflock);
+                if (!skb)
                         continue;
-                }
-                /*
-                 * Now we know it's a completed frame, we can indicate the
-                 * frame. Remove the previous holding descriptor and leave
-                 * this one in the queue as the new holding descriptor.
-                 */
-                if (bf_held) {
-                        list_del(&bf_held->list);
-                        bf_held->bf_status &= ~ATH_BUFSTATUS_STALE;
-                        if (bf_held->bf_status & ATH_BUFSTATUS_FREE) {
-                                list_add_tail(&bf_held->list, &sc->sc_rxbuf);
-                                /* try to requeue this descriptor */
-                                ath_rx_buf_link(sc, bf_held);
-                        }
-                }
 
-                bf->bf_status |= ATH_BUFSTATUS_STALE;
-                bf_held = bf;
                 /*
-                 * Release the lock here in case ieee80211_input() return
-                 * the frame immediately by calling ath_rx_mpdu_requeue().
+                 * If we're asked to flush receive queue, directly
+                 * chain it back at the queue without processing it.
                  */
-                spin_unlock_bh(&sc->sc_rxbuflock);
-
-                if (flush) {
-                        /*
-                         * If we're asked to flush receive queue, directly
-                         * chain it back at the queue without processing it.
-                         */
+                if (flush)
                         goto rx_next;
-                }
 
-                hdr = (struct ieee80211_hdr *)skb->data;
-                fc = hdr->frame_control;
-                memset(&rx_status, 0, sizeof(struct ath_recv_status));
-
-                if (ds->ds_rxstat.rs_more) {
-                        /*
-                         * Frame spans multiple descriptors; this
-                         * cannot happen yet as we don't support
-                         * jumbograms.  If not in monitor mode,
-                         * discard the frame.
-                         */
-#ifndef ERROR_FRAMES
-                        /*
-                         * Enable this if you want to see
-                         * error frames in Monitor mode.
-                         */
-                        if (sc->sc_ah->ah_opmode != ATH9K_M_MONITOR)
-                                goto rx_next;
-#endif
-                        /* fall thru for monitor mode handling... */
-                } else if (ds->ds_rxstat.rs_status != 0) {
-                        if (ds->ds_rxstat.rs_status & ATH9K_RXERR_CRC)
-                                rx_status.flags |= ATH_RX_FCS_ERROR;
-                        if (ds->ds_rxstat.rs_status & ATH9K_RXERR_PHY) {
-                                phyerr = ds->ds_rxstat.rs_phyerr & 0x1f;
-                                goto rx_next;
-                        }
+                if (!ds->ds_rxstat.rs_datalen)
+                        goto rx_next;
 
-                        if (ds->ds_rxstat.rs_status & ATH9K_RXERR_DECRYPT) {
-                                /*
-                                 * Decrypt error. We only mark packet status
-                                 * here and always push up the frame up to let
-                                 * mac80211 handle the actual error case, be
-                                 * it no decryption key or real decryption
-                                 * error. This let us keep statistics there.
-                                 */
-                                rx_status.flags |= ATH_RX_DECRYPT_ERROR;
-                        } else if (ds->ds_rxstat.rs_status & ATH9K_RXERR_MIC) {
-                                /*
-                                 * Demic error. We only mark frame status here
-                                 * and always push up the frame up to let
-                                 * mac80211 handle the actual error case. This
-                                 * let us keep statistics there. Hardware may
-                                 * post a false-positive MIC error.
-                                 */
-                                if (ieee80211_is_ctl(fc))
-                                        /*
-                                         * Sometimes, we get invalid
-                                         * MIC failures on valid control frames.
-                                         * Remove these mic errors.
-                                         */
-                                        ds->ds_rxstat.rs_status &=
-                                                ~ATH9K_RXERR_MIC;
-                                else
-                                        rx_status.flags |= ATH_RX_MIC_ERROR;
-                        }
-                        /*
-                         * Reject error frames with the exception of
-                         * decryption and MIC failures. For monitor mode,
-                         * we also ignore the CRC error.
-                         */
-                        if (sc->sc_ah->ah_opmode == ATH9K_M_MONITOR) {
-                                if (ds->ds_rxstat.rs_status &
-                                    ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
-                                        ATH9K_RXERR_CRC))
-                                        goto rx_next;
-                        } else {
-                                if (ds->ds_rxstat.rs_status &
-                                    ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
-                                        goto rx_next;
-                                }
-                        }
-                }
-                /*
-                 * The status portion of the descriptor could get corrupted.
-                 */
+                /* The status portion of the descriptor could get corrupted. */
                 if (sc->sc_rxbufsize < ds->ds_rxstat.rs_datalen)
                         goto rx_next;
-                /*
-                 * Sync and unmap the frame.  At this point we're
-                 * committed to passing the sk_buff somewhere so
-                 * clear buf_skb; this means a new sk_buff must be
-                 * allocated when the rx descriptor is setup again
-                 * to receive another frame.
-                 */
-                skb_put(skb, ds->ds_rxstat.rs_datalen);
-                skb->protocol = cpu_to_be16(ETH_P_CONTROL);
-                rx_status.tsf = ath_extend_tsf(sc, ds->ds_rxstat.rs_tstamp);
-                rx_status.rateieee =
-                        sc->sc_hwmap[ds->ds_rxstat.rs_rate].ieeerate;
-                rx_status.rateKbps =
-                        sc->sc_hwmap[ds->ds_rxstat.rs_rate].rateKbps;
-                rx_status.ratecode = ds->ds_rxstat.rs_rate;
-
-                /* HT rate */
-                if (rx_status.ratecode & 0x80) {
-                        /* TODO - add table to avoid division */
-                        if (ds->ds_rxstat.rs_flags & ATH9K_RX_2040) {
-                                rx_status.flags |= ATH_RX_40MHZ;
-                                rx_status.rateKbps =
-                                        (rx_status.rateKbps * 27) / 13;
-                        }
-                        if (ds->ds_rxstat.rs_flags & ATH9K_RX_GI)
-                                rx_status.rateKbps =
-                                        (rx_status.rateKbps * 10) / 9;
-                        else
-                                rx_status.flags |= ATH_RX_SHORT_GI;
-                }
 
-                /* sc_noise_floor is only available when the station
-                   attaches to an AP, so we use a default value
-                   if we are not yet attached. */
-                rx_status.abs_rssi =
-                        ds->ds_rxstat.rs_rssi + sc->sc_ani.sc_noise_floor;
+                if (!ath_rx_prepare(skb, ds, &rx_status, &decrypt_error, sc))
+                        goto rx_next;
 
-                pci_dma_sync_single_for_cpu(sc->pdev,
-                                            bf->bf_buf_addr,
+                /* Sync and unmap the frame */
+                pci_dma_sync_single_for_cpu(sc->pdev, bf->bf_buf_addr,
                                             skb_tailroom(skb),
                                             PCI_DMA_FROMDEVICE);
-                pci_unmap_single(sc->pdev,
-                                 bf->bf_buf_addr,
+                pci_unmap_single(sc->pdev, bf->bf_buf_addr,
                                  sc->sc_rxbufsize,
                                  PCI_DMA_FROMDEVICE);
 
-                /* XXX: Ah! make me more readable, use a helper */
-                if (ah->ah_caps.hw_caps & ATH9K_HW_CAP_HT) {
-                        if (ds->ds_rxstat.rs_moreaggr == 0) {
-                                rx_status.rssictl[0] =
-                                        ds->ds_rxstat.rs_rssi_ctl0;
-                                rx_status.rssictl[1] =
-                                        ds->ds_rxstat.rs_rssi_ctl1;
-                                rx_status.rssictl[2] =
-                                        ds->ds_rxstat.rs_rssi_ctl2;
-                                rx_status.rssi = ds->ds_rxstat.rs_rssi;
-                                if (ds->ds_rxstat.rs_flags & ATH9K_RX_2040) {
-                                        rx_status.rssiextn[0] =
-                                                ds->ds_rxstat.rs_rssi_ext0;
-                                        rx_status.rssiextn[1] =
-                                                ds->ds_rxstat.rs_rssi_ext1;
-                                        rx_status.rssiextn[2] =
-                                                ds->ds_rxstat.rs_rssi_ext2;
-                                        rx_status.flags |=
-                                                ATH_RX_RSSI_EXTN_VALID;
-                                }
-                                rx_status.flags |= ATH_RX_RSSI_VALID |
-                                        ATH_RX_CHAIN_RSSI_VALID;
-                        }
-                } else {
-                        /*
-                         * Need to insert the "combined" rssi into the
-                         * status structure for upper layer processing
-                         */
-                        rx_status.rssi = ds->ds_rxstat.rs_rssi;
-                        rx_status.flags |= ATH_RX_RSSI_VALID;
+                skb_put(skb, ds->ds_rxstat.rs_datalen);
+                skb->protocol = cpu_to_be16(ETH_P_CONTROL);
+
+                /* see if any padding is done by the hw and remove it */
+                hdr = (struct ieee80211_hdr *)skb->data;
+                hdrlen = ieee80211_get_hdrlen_from_skb(skb);
+
+                if (hdrlen & 3) {
+                        padsize = hdrlen % 4;
+                        memmove(skb->data + padsize, skb->data, hdrlen);
+                        skb_pull(skb, padsize);
                 }
 
-                /* Pass frames up to the stack. */
+                keyix = ds->ds_rxstat.rs_keyix;
 
-                type = ath_rx_indicate(sc, skb,
-                        &rx_status, ds->ds_rxstat.rs_keyix);
+                if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error) {
+                        rx_status.flag |= RX_FLAG_DECRYPTED;
+                } else if ((le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_PROTECTED)
+                           && !decrypt_error && skb->len >= hdrlen + 4) {
+                        keyix = skb->data[hdrlen + 3] >> 6;
+
+                        if (test_bit(keyix, sc->sc_keymap))
+                                rx_status.flag |= RX_FLAG_DECRYPTED;
+                }
+
+                /* Send the frame to mac80211 */
+                __ieee80211_rx(sc->hw, skb, &rx_status);
+                bf->bf_mpdu = NULL;
 
                 /*
                  * change the default rx antenna if rx diversity chooses the
@@ -716,37 +575,15 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush)
                  */
                 if (sc->sc_defant != ds->ds_rxstat.rs_antenna) {
                         if (++sc->sc_rxotherant >= 3)
-                                ath_setdefantenna(sc,
-                                                ds->ds_rxstat.rs_antenna);
+                                ath_setdefantenna(sc, ds->ds_rxstat.rs_antenna);
                 } else {
                         sc->sc_rxotherant = 0;
                 }
-
-#ifdef CONFIG_SLOW_ANT_DIV
-                if ((rx_status.flags & ATH_RX_RSSI_VALID) &&
-                    ieee80211_is_beacon(fc)) {
-                        ath_slow_ant_div(&sc->sc_antdiv, hdr, &ds->ds_rxstat);
-                }
-#endif
-                /*
-                 * For frames successfully indicated, the buffer will be
-                 * returned to us by upper layers by calling
-                 * ath_rx_mpdu_requeue, either synchronusly or asynchronously.
-                 * So we don't want to do it here in this loop.
-                 */
-                continue;
-
 rx_next:
-                bf->bf_status |= ATH_BUFSTATUS_FREE;
-        } while (TRUE);
-
-        if (chainreset) {
-                DPRINTF(sc, ATH_DBG_CONFIG,
-                        "%s: Reset rx chain mask. "
-                        "Do internal reset\n", __func__);
-                ASSERT(flush == 0);
-                ath_reset(sc, false);
-        }
+                ath_rx_requeue(sc, bf);
+        } while (1);
+
+        spin_unlock_bh(&sc->sc_rxbuflock);
 
         return 0;
 #undef PA2DESC