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path: root/drivers/net/wireless/ath/ath9k/recv.c
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Diffstat (limited to 'drivers/net/wireless/ath/ath9k/recv.c')
-rw-r--r--drivers/net/wireless/ath/ath9k/recv.c834
1 files changed, 834 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
new file mode 100644
index 000000000000..5014a19b0f75
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -0,0 +1,834 @@
+/*
+ * Copyright (c) 2008-2009 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"
+
+static struct ieee80211_hw * ath_get_virt_hw(struct ath_softc *sc,
+ struct ieee80211_hdr *hdr)
+{
+ struct ieee80211_hw *hw = sc->pri_wiphy->hw;
+ int i;
+
+ spin_lock_bh(&sc->wiphy_lock);
+ for (i = 0; i < sc->num_sec_wiphy; i++) {
+ struct ath_wiphy *aphy = sc->sec_wiphy[i];
+ if (aphy == NULL)
+ continue;
+ if (compare_ether_addr(hdr->addr1, aphy->hw->wiphy->perm_addr)
+ == 0) {
+ hw = aphy->hw;
+ break;
+ }
+ }
+ spin_unlock_bh(&sc->wiphy_lock);
+ return hw;
+}
+
+/*
+ * Setup and link descriptors.
+ *
+ * 11N: we can no longer afford to self link the last descriptor.
+ * 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.
+ */
+static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
+{
+ struct ath_hw *ah = sc->sc_ah;
+ struct ath_desc *ds;
+ struct sk_buff *skb;
+
+ ATH_RXBUF_RESET(bf);
+
+ ds = bf->bf_desc;
+ ds->ds_link = 0; /* link to null */
+ ds->ds_data = bf->bf_buf_addr;
+
+ /* virtual addr of the beginning of the buffer. */
+ skb = bf->bf_mpdu;
+ ASSERT(skb != NULL);
+ ds->ds_vdata = skb->data;
+
+ /* setup rx descriptors. The rx.bufsize here tells the harware
+ * how much data it can DMA to us and that we are prepared
+ * to process */
+ ath9k_hw_setuprxdesc(ah, ds,
+ sc->rx.bufsize,
+ 0);
+
+ if (sc->rx.rxlink == NULL)
+ ath9k_hw_putrxbuf(ah, bf->bf_daddr);
+ else
+ *sc->rx.rxlink = bf->bf_daddr;
+
+ sc->rx.rxlink = &ds->ds_link;
+ ath9k_hw_rxena(ah);
+}
+
+static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)
+{
+ /* XXX block beacon interrupts */
+ ath9k_hw_setantenna(sc->sc_ah, antenna);
+ sc->rx.defant = antenna;
+ sc->rx.rxotherant = 0;
+}
+
+/*
+ * Extend 15-bit time stamp from rx descriptor to
+ * a full 64-bit TSF using the current h/w TSF.
+*/
+static u64 ath_extend_tsf(struct ath_softc *sc, u32 rstamp)
+{
+ u64 tsf;
+
+ tsf = ath9k_hw_gettsf64(sc->sc_ah);
+ if ((tsf & 0x7fff) < rstamp)
+ tsf -= 0x8000;
+ return (tsf & ~0x7fff) | rstamp;
+}
+
+static struct sk_buff *ath_rxbuf_alloc(struct ath_softc *sc, u32 len, gfp_t gfp_mask)
+{
+ struct sk_buff *skb;
+ u32 off;
+
+ /*
+ * Cache-line-align. This is important (for the
+ * 5210 at least) as not doing so causes bogus data
+ * in rx'd frames.
+ */
+
+ /* Note: the kernel can allocate a value greater than
+ * what we ask it to give us. We really only need 4 KB as that
+ * is this hardware supports and in fact we need at least 3849
+ * as that is the MAX AMSDU size this hardware supports.
+ * Unfortunately this means we may get 8 KB here from the
+ * kernel... and that is actually what is observed on some
+ * systems :( */
+ skb = __dev_alloc_skb(len + sc->cachelsz - 1, gfp_mask);
+ if (skb != NULL) {
+ off = ((unsigned long) skb->data) % sc->cachelsz;
+ if (off != 0)
+ skb_reserve(skb, sc->cachelsz - off);
+ } else {
+ DPRINTF(sc, ATH_DBG_FATAL,
+ "skbuff alloc of size %u failed\n", len);
+ return NULL;
+ }
+
+ return skb;
+}
+
+/*
+ * 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_prepare(struct sk_buff *skb, struct ath_desc *ds,
+ struct ieee80211_rx_status *rx_status, bool *decrypt_error,
+ struct ath_softc *sc)
+{
+ struct ieee80211_hdr *hdr;
+ u8 ratecode;
+ __le16 fc;
+ struct ieee80211_hw *hw;
+
+ hdr = (struct ieee80211_hdr *)skb->data;
+ fc = hdr->frame_control;
+ memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
+ hw = ath_get_virt_hw(sc, hdr);
+
+ 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->opmode != NL80211_IFTYPE_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;
+
+ 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->opmode == NL80211_IFTYPE_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;
+ }
+ }
+ }
+
+ ratecode = ds->ds_rxstat.rs_rate;
+
+ if (ratecode & 0x80) {
+ /* HT rate */
+ rx_status->flag |= RX_FLAG_HT;
+ if (ds->ds_rxstat.rs_flags & ATH9K_RX_2040)
+ rx_status->flag |= RX_FLAG_40MHZ;
+ if (ds->ds_rxstat.rs_flags & ATH9K_RX_GI)
+ rx_status->flag |= RX_FLAG_SHORT_GI;
+ rx_status->rate_idx = ratecode & 0x7f;
+ } else {
+ int i = 0, cur_band, n_rates;
+
+ 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].hw_value ==
+ ratecode) {
+ rx_status->rate_idx = i;
+ break;
+ }
+
+ if (sc->sbands[cur_band].bitrates[i].hw_value_short ==
+ ratecode) {
+ rx_status->rate_idx = i;
+ rx_status->flag |= RX_FLAG_SHORTPRE;
+ break;
+ }
+ }
+ }
+
+ rx_status->mactime = ath_extend_tsf(sc, ds->ds_rxstat.rs_tstamp);
+ rx_status->band = hw->conf.channel->band;
+ rx_status->freq = hw->conf.channel->center_freq;
+ rx_status->noise = sc->ani.noise_floor;
+ rx_status->signal = rx_status->noise + ds->ds_rxstat.rs_rssi;
+ 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)
+{
+ struct ath_hw *ah = sc->sc_ah;
+ u32 rfilt, mfilt[2];
+
+ /* configure rx filter */
+ rfilt = ath_calcrxfilter(sc);
+ ath9k_hw_setrxfilter(ah, rfilt);
+
+ /* configure bssid mask */
+ if (ah->caps.hw_caps & ATH9K_HW_CAP_BSSIDMASK)
+ ath9k_hw_setbssidmask(sc);
+
+ /* configure operational mode */
+ ath9k_hw_setopmode(ah);
+
+ /* Handle any link-level address change. */
+ ath9k_hw_setmac(ah, sc->sc_ah->macaddr);
+
+ /* calculate and install multicast filter */
+ mfilt[0] = mfilt[1] = ~0;
+ ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
+}
+
+int ath_rx_init(struct ath_softc *sc, int nbufs)
+{
+ 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);
+
+ sc->rx.bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
+ min(sc->cachelsz, (u16)64));
+
+ DPRINTF(sc, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
+ sc->cachelsz, sc->rx.bufsize);
+
+ /* Initialize rx descriptors */
+
+ error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
+ "rx", nbufs, 1);
+ if (error != 0) {
+ DPRINTF(sc, ATH_DBG_FATAL,
+ "failed to allocate rx descriptors: %d\n", error);
+ goto err;
+ }
+
+ list_for_each_entry(bf, &sc->rx.rxbuf, list) {
+ skb = ath_rxbuf_alloc(sc, sc->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,
+ sc->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;
+ DPRINTF(sc, 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;
+
+err:
+ if (error)
+ ath_rx_cleanup(sc);
+
+ return error;
+}
+
+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,
+ sc->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);
+}
+
+/*
+ * Calculate the receive filter according to the
+ * operating mode and state:
+ *
+ * o always accept unicast, broadcast, and multicast traffic
+ * o maintain current state of phy error reception (the hal
+ * may enable phy error frames for noise immunity work)
+ * o probe request frames are accepted only when operating in
+ * hostap, adhoc, or monitor modes
+ * o enable promiscuous mode according to the interface state
+ * o accept beacons:
+ * - when operating in adhoc mode so the 802.11 layer creates
+ * node table entries for peers,
+ * - when operating in station mode for collecting rssi data when
+ * the station is otherwise quiet, or
+ * - when operating as a repeater so we see repeater-sta beacons
+ * - when scanning
+ */
+
+u32 ath_calcrxfilter(struct ath_softc *sc)
+{
+#define RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
+
+ u32 rfilt;
+
+ rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) & RX_FILTER_PRESERVE)
+ | ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
+ | ATH9K_RX_FILTER_MCAST;
+
+ /* If not a STA, enable processing of Probe Requests */
+ if (sc->sc_ah->opmode != NL80211_IFTYPE_STATION)
+ rfilt |= ATH9K_RX_FILTER_PROBEREQ;
+
+ /*
+ * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
+ * mode interface or when in monitor mode. AP mode does not need this
+ * since it receives all in-BSS frames anyway.
+ */
+ if (((sc->sc_ah->opmode != NL80211_IFTYPE_AP) &&
+ (sc->rx.rxfilter & FIF_PROMISC_IN_BSS)) ||
+ (sc->sc_ah->opmode == NL80211_IFTYPE_MONITOR))
+ rfilt |= ATH9K_RX_FILTER_PROM;
+
+ if (sc->rx.rxfilter & FIF_CONTROL)
+ rfilt |= ATH9K_RX_FILTER_CONTROL;
+
+ if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
+ !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
+ rfilt |= ATH9K_RX_FILTER_MYBEACON;
+ else
+ rfilt |= ATH9K_RX_FILTER_BEACON;
+
+ /* If in HOSTAP mode, want to enable reception of PSPOLL frames */
+ if (sc->sc_ah->opmode == NL80211_IFTYPE_AP)
+ rfilt |= ATH9K_RX_FILTER_PSPOLL;
+
+ if (sc->sec_wiphy) {
+ /* TODO: only needed if more than one BSSID is in use in
+ * station/adhoc mode */
+ /* TODO: for older chips, may need to add ATH9K_RX_FILTER_PROM
+ */
+ rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
+ }
+
+ return rfilt;
+
+#undef RX_FILTER_PRESERVE
+}
+
+int ath_startrecv(struct ath_softc *sc)
+{
+ struct ath_hw *ah = sc->sc_ah;
+ struct ath_buf *bf, *tbf;
+
+ spin_lock_bh(&sc->rx.rxbuflock);
+ if (list_empty(&sc->rx.rxbuf))
+ goto start_recv;
+
+ sc->rx.rxlink = NULL;
+ list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
+ ath_rx_buf_link(sc, bf);
+ }
+
+ /* We could have deleted elements so the list may be empty now */
+ if (list_empty(&sc->rx.rxbuf))
+ goto start_recv;
+
+ bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
+ ath9k_hw_putrxbuf(ah, bf->bf_daddr);
+ ath9k_hw_rxena(ah);
+
+start_recv:
+ spin_unlock_bh(&sc->rx.rxbuflock);
+ ath_opmode_init(sc);
+ ath9k_hw_startpcureceive(ah);
+
+ return 0;
+}
+
+bool ath_stoprecv(struct ath_softc *sc)
+{
+ struct ath_hw *ah = sc->sc_ah;
+ bool stopped;
+
+ ath9k_hw_stoppcurecv(ah);
+ ath9k_hw_setrxfilter(ah, 0);
+ stopped = ath9k_hw_stopdmarecv(ah);
+ sc->rx.rxlink = NULL;
+
+ return stopped;
+}
+
+void ath_flushrecv(struct ath_softc *sc)
+{
+ spin_lock_bh(&sc->rx.rxflushlock);
+ sc->sc_flags |= SC_OP_RXFLUSH;
+ ath_rx_tasklet(sc, 1);
+ sc->sc_flags &= ~SC_OP_RXFLUSH;
+ spin_unlock_bh(&sc->rx.rxflushlock);
+}
+
+static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
+{
+ /* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
+ struct ieee80211_mgmt *mgmt;
+ u8 *pos, *end, id, elen;
+ struct ieee80211_tim_ie *tim;
+
+ mgmt = (struct ieee80211_mgmt *)skb->data;
+ pos = mgmt->u.beacon.variable;
+ end = skb->data + skb->len;
+
+ while (pos + 2 < end) {
+ id = *pos++;
+ elen = *pos++;
+ if (pos + elen > end)
+ break;
+
+ if (id == WLAN_EID_TIM) {
+ if (elen < sizeof(*tim))
+ break;
+ tim = (struct ieee80211_tim_ie *) pos;
+ if (tim->dtim_count != 0)
+ break;
+ return tim->bitmap_ctrl & 0x01;
+ }
+
+ pos += elen;
+ }
+
+ return false;
+}
+
+static void ath_rx_ps_back_to_sleep(struct ath_softc *sc)
+{
+ sc->sc_flags &= ~(SC_OP_WAIT_FOR_BEACON | SC_OP_WAIT_FOR_CAB);
+}
+
+static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
+{
+ struct ieee80211_mgmt *mgmt;
+
+ if (skb->len < 24 + 8 + 2 + 2)
+ return;
+
+ mgmt = (struct ieee80211_mgmt *)skb->data;
+ if (memcmp(sc->curbssid, mgmt->bssid, ETH_ALEN) != 0)
+ return; /* not from our current AP */
+
+ if (sc->sc_flags & SC_OP_BEACON_SYNC) {
+ sc->sc_flags &= ~SC_OP_BEACON_SYNC;
+ DPRINTF(sc, ATH_DBG_PS, "Reconfigure Beacon timers based on "
+ "timestamp from the AP\n");
+ ath_beacon_config(sc, NULL);
+ }
+
+ if (!(sc->hw->conf.flags & IEEE80211_CONF_PS)) {
+ /* We are not in PS mode anymore; remain awake */
+ DPRINTF(sc, ATH_DBG_PS, "Not in PS mode anymore, remain "
+ "awake\n");
+ sc->sc_flags &= ~(SC_OP_WAIT_FOR_BEACON | SC_OP_WAIT_FOR_CAB);
+ return;
+ }
+
+ if (ath_beacon_dtim_pending_cab(skb)) {
+ /*
+ * Remain awake waiting for buffered broadcast/multicast
+ * frames.
+ */
+ DPRINTF(sc, ATH_DBG_PS, "Received DTIM beacon indicating "
+ "buffered broadcast/multicast frame(s)\n");
+ sc->sc_flags |= SC_OP_WAIT_FOR_CAB;
+ return;
+ }
+
+ if (sc->sc_flags & SC_OP_WAIT_FOR_CAB) {
+ /*
+ * This can happen if a broadcast frame is dropped or the AP
+ * fails to send a frame indicating that all CAB frames have
+ * been delivered.
+ */
+ DPRINTF(sc, ATH_DBG_PS, "PS wait for CAB frames timed out\n");
+ }
+
+ /* No more broadcast/multicast frames to be received at this point. */
+ ath_rx_ps_back_to_sleep(sc);
+}
+
+static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb)
+{
+ struct ieee80211_hdr *hdr;
+
+ hdr = (struct ieee80211_hdr *)skb->data;
+
+ /* Process Beacon and CAB receive in PS state */
+ if ((sc->sc_flags & SC_OP_WAIT_FOR_BEACON) &&
+ ieee80211_is_beacon(hdr->frame_control))
+ ath_rx_ps_beacon(sc, skb);
+ else if ((sc->sc_flags & SC_OP_WAIT_FOR_CAB) &&
+ (ieee80211_is_data(hdr->frame_control) ||
+ ieee80211_is_action(hdr->frame_control)) &&
+ is_multicast_ether_addr(hdr->addr1) &&
+ !ieee80211_has_moredata(hdr->frame_control)) {
+ DPRINTF(sc, ATH_DBG_PS, "All PS CAB frames received, back to "
+ "sleep\n");
+ /*
+ * No more broadcast/multicast frames to be received at this
+ * point.
+ */
+ ath_rx_ps_back_to_sleep(sc);
+ } else if ((sc->sc_flags & SC_OP_WAIT_FOR_PSPOLL_DATA) &&
+ !is_multicast_ether_addr(hdr->addr1) &&
+ !ieee80211_has_morefrags(hdr->frame_control)) {
+ sc->sc_flags &= ~SC_OP_WAIT_FOR_PSPOLL_DATA;
+ DPRINTF(sc, ATH_DBG_PS, "Going back to sleep after having "
+ "received PS-Poll data (0x%x)\n",
+ sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
+ SC_OP_WAIT_FOR_CAB |
+ SC_OP_WAIT_FOR_PSPOLL_DATA |
+ SC_OP_WAIT_FOR_TX_ACK));
+ }
+}
+
+static void ath_rx_send_to_mac80211(struct ath_softc *sc, struct sk_buff *skb,
+ struct ieee80211_rx_status *rx_status)
+{
+ struct ieee80211_hdr *hdr;
+
+ hdr = (struct ieee80211_hdr *)skb->data;
+
+ /* Send the frame to mac80211 */
+ if (is_multicast_ether_addr(hdr->addr1)) {
+ int i;
+ /*
+ * Deliver broadcast/multicast frames to all suitable
+ * virtual wiphys.
+ */
+ /* TODO: filter based on channel configuration */
+ for (i = 0; i < sc->num_sec_wiphy; i++) {
+ struct ath_wiphy *aphy = sc->sec_wiphy[i];
+ struct sk_buff *nskb;
+ if (aphy == NULL)
+ continue;
+ nskb = skb_copy(skb, GFP_ATOMIC);
+ if (nskb)
+ __ieee80211_rx(aphy->hw, nskb, rx_status);
+ }
+ __ieee80211_rx(sc->hw, skb, rx_status);
+ } else {
+ /* Deliver unicast frames based on receiver address */
+ __ieee80211_rx(ath_get_virt_hw(sc, hdr), skb, rx_status);
+ }
+}
+
+int ath_rx_tasklet(struct ath_softc *sc, int flush)
+{
+#define PA2DESC(_sc, _pa) \
+ ((struct ath_desc *)((caddr_t)(_sc)->rx.rxdma.dd_desc + \
+ ((_pa) - (_sc)->rx.rxdma.dd_desc_paddr)))
+
+ struct ath_buf *bf;
+ struct ath_desc *ds;
+ struct sk_buff *skb = NULL, *requeue_skb;
+ struct ieee80211_rx_status rx_status;
+ struct ath_hw *ah = sc->sc_ah;
+ struct ieee80211_hdr *hdr;
+ int hdrlen, padsize, retval;
+ bool decrypt_error = false;
+ u8 keyix;
+ __le16 fc;
+
+ spin_lock_bh(&sc->rx.rxbuflock);
+
+ do {
+ /* If handling rx interrupt and flush is in progress => exit */
+ 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.
+ */
+ retval = ath9k_hw_rxprocdesc(ah, ds,
+ bf->bf_daddr,
+ PA2DESC(sc, ds->ds_link),
+ 0);
+ if (retval == -EINPROGRESS) {
+ struct ath_buf *tbf;
+ struct ath_desc *tds;
+
+ if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
+ sc->rx.rxlink = NULL;
+ break;
+ }
+
+ 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, tbf->bf_daddr,
+ PA2DESC(sc, tds->ds_link), 0);
+ if (retval == -EINPROGRESS) {
+ 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,
+ sc->rx.bufsize,
+ DMA_FROM_DEVICE);
+
+ /*
+ * If we're asked to flush receive queue, directly
+ * chain it back at the queue without processing it.
+ */
+ if (flush)
+ goto requeue;
+
+ if (!ds->ds_rxstat.rs_datalen)
+ goto requeue;
+
+ /* The status portion of the descriptor could get corrupted. */
+ if (sc->rx.bufsize < ds->ds_rxstat.rs_datalen)
+ goto requeue;
+
+ if (!ath_rx_prepare(skb, ds, &rx_status, &decrypt_error, sc))
+ goto requeue;
+
+ /* Ensure we always have an skb to requeue once we are done
+ * processing the current buffer's skb */
+ requeue_skb = ath_rxbuf_alloc(sc, sc->rx.bufsize, GFP_ATOMIC);
+
+ /* If there is no memory we ignore the current RX'd frame,
+ * tell hardware it can give us a new frame using the old
+ * skb and put it at the tail of the sc->rx.rxbuf list for
+ * processing. */
+ if (!requeue_skb)
+ goto requeue;
+
+ /* Unmap the frame */
+ dma_unmap_single(sc->dev, bf->bf_buf_addr,
+ sc->rx.bufsize,
+ DMA_FROM_DEVICE);
+
+ 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);
+ fc = hdr->frame_control;
+
+ /* The MAC header is padded to have 32-bit boundary if the
+ * packet payload is non-zero. The general calculation for
+ * padsize would take into account odd header lengths:
+ * padsize = (4 - hdrlen % 4) % 4; However, since only
+ * even-length headers are used, padding can only be 0 or 2
+ * bytes and we can optimize this a bit. In addition, we must
+ * not try to remove padding from short control frames that do
+ * not have payload. */
+ padsize = hdrlen & 3;
+ if (padsize && hdrlen >= 24) {
+ memmove(skb->data + padsize, skb->data, hdrlen);
+ skb_pull(skb, padsize);
+ }
+
+ keyix = ds->ds_rxstat.rs_keyix;
+
+ if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error) {
+ rx_status.flag |= RX_FLAG_DECRYPTED;
+ } else if (ieee80211_has_protected(fc)
+ && !decrypt_error && skb->len >= hdrlen + 4) {
+ keyix = skb->data[hdrlen + 3] >> 6;
+
+ if (test_bit(keyix, sc->keymap))
+ rx_status.flag |= RX_FLAG_DECRYPTED;
+ }
+ if (ah->sw_mgmt_crypto &&
+ (rx_status.flag & RX_FLAG_DECRYPTED) &&
+ ieee80211_is_mgmt(fc)) {
+ /* Use software decrypt for management frames. */
+ rx_status.flag &= ~RX_FLAG_DECRYPTED;
+ }
+
+ /* We will now give hardware our shiny new allocated skb */
+ bf->bf_mpdu = requeue_skb;
+ bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
+ sc->rx.bufsize,
+ DMA_FROM_DEVICE);
+ if (unlikely(dma_mapping_error(sc->dev,
+ bf->bf_buf_addr))) {
+ dev_kfree_skb_any(requeue_skb);
+ bf->bf_mpdu = NULL;
+ DPRINTF(sc, ATH_DBG_FATAL,
+ "dma_mapping_error() on RX\n");
+ ath_rx_send_to_mac80211(sc, skb, &rx_status);
+ break;
+ }
+ bf->bf_dmacontext = bf->bf_buf_addr;
+
+ /*
+ * change the default rx antenna if rx diversity chooses the
+ * other antenna 3 times in a row.
+ */
+ if (sc->rx.defant != ds->ds_rxstat.rs_antenna) {
+ if (++sc->rx.rxotherant >= 3)
+ ath_setdefantenna(sc, ds->ds_rxstat.rs_antenna);
+ } else {
+ sc->rx.rxotherant = 0;
+ }
+
+ if (unlikely(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
+ SC_OP_WAIT_FOR_PSPOLL_DATA)))
+ ath_rx_ps(sc, skb);
+
+ ath_rx_send_to_mac80211(sc, skb, &rx_status);
+
+requeue:
+ 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
+}