Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1125 insertions, 0 deletions

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmsmac/ampdu.c b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/ampdu.c
new file mode 100644
index 000000000..c9fb4b0cf
--- /dev/null
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmsmac/ampdu.c
@@ -0,0 +1,1125 @@
+/*
+ * Copyright (c) 2010 Broadcom Corporation
+ *
+ * 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 <net/mac80211.h>
+
+#include "rate.h"
+#include "scb.h"
+#include "phy/phy_hal.h"
+#include "antsel.h"
+#include "main.h"
+#include "ampdu.h"
+#include "debug.h"
+#include "brcms_trace_events.h"
+
+/* max number of mpdus in an ampdu */
+#define AMPDU_MAX_MPDU			32
+/* max number of mpdus in an ampdu to a legacy */
+#define AMPDU_NUM_MPDU_LEGACY		16
+/* max Tx ba window size (in pdu) */
+#define AMPDU_TX_BA_MAX_WSIZE		64
+/* default Tx ba window size (in pdu) */
+#define AMPDU_TX_BA_DEF_WSIZE		64
+/* default Rx ba window size (in pdu) */
+#define AMPDU_RX_BA_DEF_WSIZE		64
+/* max Rx ba window size (in pdu) */
+#define AMPDU_RX_BA_MAX_WSIZE		64
+/* max dur of tx ampdu (in msec) */
+#define	AMPDU_MAX_DUR			5
+/* default tx retry limit */
+#define AMPDU_DEF_RETRY_LIMIT		5
+/* default tx retry limit at reg rate */
+#define AMPDU_DEF_RR_RETRY_LIMIT	2
+/* default ffpld reserved bytes */
+#define AMPDU_DEF_FFPLD_RSVD		2048
+/* # of inis to be freed on detach */
+#define AMPDU_INI_FREE			10
+/* max # of mpdus released at a time */
+#define	AMPDU_SCB_MAX_RELEASE		20
+
+#define NUM_FFPLD_FIFO 4	/* number of fifo concerned by pre-loading */
+#define FFPLD_TX_MAX_UNFL   200	/* default value of the average number of ampdu
+				 * without underflows
+				 */
+#define FFPLD_MPDU_SIZE 1800	/* estimate of maximum mpdu size */
+#define FFPLD_MAX_MCS 23	/* we don't deal with mcs 32 */
+#define FFPLD_PLD_INCR 1000	/* increments in bytes */
+#define FFPLD_MAX_AMPDU_CNT 5000	/* maximum number of ampdu we
+					 * accumulate between resets.
+					 */
+
+#define AMPDU_DELIMITER_LEN	4
+
+/* max allowed number of mpdus in an ampdu (2 streams) */
+#define AMPDU_NUM_MPDU		16
+
+#define TX_SEQ_TO_INDEX(seq) ((seq) % AMPDU_TX_BA_MAX_WSIZE)
+
+/* max possible overhead per mpdu in the ampdu; 3 is for roundup if needed */
+#define AMPDU_MAX_MPDU_OVERHEAD (FCS_LEN + DOT11_ICV_AES_LEN +\
+	AMPDU_DELIMITER_LEN + 3\
+	+ DOT11_A4_HDR_LEN + DOT11_QOS_LEN + DOT11_IV_MAX_LEN)
+
+/* modulo add/sub, bound = 2^k */
+#define MODADD_POW2(x, y, bound) (((x) + (y)) & ((bound) - 1))
+#define MODSUB_POW2(x, y, bound) (((x) - (y)) & ((bound) - 1))
+
+/* structure to hold tx fifo information and pre-loading state
+ * counters specific to tx underflows of ampdus
+ * some counters might be redundant with the ones in wlc or ampdu structures.
+ * This allows to maintain a specific state independently of
+ * how often and/or when the wlc counters are updated.
+ *
+ * ampdu_pld_size: number of bytes to be pre-loaded
+ * mcs2ampdu_table: per-mcs max # of mpdus in an ampdu
+ * prev_txfunfl: num of underflows last read from the HW macstats counter
+ * accum_txfunfl: num of underflows since we modified pld params
+ * accum_txampdu: num of tx ampdu since we modified pld params
+ * prev_txampdu: previous reading of tx ampdu
+ * dmaxferrate: estimated dma avg xfer rate in kbits/sec
+ */
+struct brcms_fifo_info {
+	u16 ampdu_pld_size;
+	u8 mcs2ampdu_table[FFPLD_MAX_MCS + 1];
+	u16 prev_txfunfl;
+	u32 accum_txfunfl;
+	u32 accum_txampdu;
+	u32 prev_txampdu;
+	u32 dmaxferrate;
+};
+
+/* AMPDU module specific state
+ *
+ * wlc: pointer to main wlc structure
+ * scb_handle: scb cubby handle to retrieve data from scb
+ * ini_enable: per-tid initiator enable/disable of ampdu
+ * ba_tx_wsize: Tx ba window size (in pdu)
+ * ba_rx_wsize: Rx ba window size (in pdu)
+ * retry_limit: mpdu transmit retry limit
+ * rr_retry_limit: mpdu transmit retry limit at regular rate
+ * retry_limit_tid: per-tid mpdu transmit retry limit
+ * rr_retry_limit_tid: per-tid mpdu transmit retry limit at regular rate
+ * mpdu_density: min mpdu spacing (0-7) ==> 2^(x-1)/8 usec
+ * max_pdu: max pdus allowed in ampdu
+ * dur: max duration of an ampdu (in msec)
+ * rx_factor: maximum rx ampdu factor (0-3) ==> 2^(13+x) bytes
+ * ffpld_rsvd: number of bytes to reserve for preload
+ * max_txlen: max size of ampdu per mcs, bw and sgi
+ * mfbr: enable multiple fallback rate
+ * tx_max_funl: underflows should be kept such that
+ *		(tx_max_funfl*underflows) < tx frames
+ * fifo_tb: table of fifo infos
+ */
+struct ampdu_info {
+	struct brcms_c_info *wlc;
+	int scb_handle;
+	u8 ini_enable[AMPDU_MAX_SCB_TID];
+	u8 ba_tx_wsize;
+	u8 ba_rx_wsize;
+	u8 retry_limit;
+	u8 rr_retry_limit;
+	u8 retry_limit_tid[AMPDU_MAX_SCB_TID];
+	u8 rr_retry_limit_tid[AMPDU_MAX_SCB_TID];
+	u8 mpdu_density;
+	s8 max_pdu;
+	u8 dur;
+	u8 rx_factor;
+	u32 ffpld_rsvd;
+	u32 max_txlen[MCS_TABLE_SIZE][2][2];
+	bool mfbr;
+	u32 tx_max_funl;
+	struct brcms_fifo_info fifo_tb[NUM_FFPLD_FIFO];
+};
+
+/* used for flushing ampdu packets */
+struct cb_del_ampdu_pars {
+	struct ieee80211_sta *sta;
+	u16 tid;
+};
+
+static void brcms_c_scb_ampdu_update_max_txlen(struct ampdu_info *ampdu, u8 dur)
+{
+	u32 rate, mcs;
+
+	for (mcs = 0; mcs < MCS_TABLE_SIZE; mcs++) {
+		/* rate is in Kbps; dur is in msec ==> len = (rate * dur) / 8 */
+		/* 20MHz, No SGI */
+		rate = mcs_2_rate(mcs, false, false);
+		ampdu->max_txlen[mcs][0][0] = (rate * dur) >> 3;
+		/* 40 MHz, No SGI */
+		rate = mcs_2_rate(mcs, true, false);
+		ampdu->max_txlen[mcs][1][0] = (rate * dur) >> 3;
+		/* 20MHz, SGI */
+		rate = mcs_2_rate(mcs, false, true);
+		ampdu->max_txlen[mcs][0][1] = (rate * dur) >> 3;
+		/* 40 MHz, SGI */
+		rate = mcs_2_rate(mcs, true, true);
+		ampdu->max_txlen[mcs][1][1] = (rate * dur) >> 3;
+	}
+}
+
+static bool brcms_c_ampdu_cap(struct ampdu_info *ampdu)
+{
+	if (BRCMS_PHY_11N_CAP(ampdu->wlc->band))
+		return true;
+	else
+		return false;
+}
+
+static int brcms_c_ampdu_set(struct ampdu_info *ampdu, bool on)
+{
+	struct brcms_c_info *wlc = ampdu->wlc;
+	struct bcma_device *core = wlc->hw->d11core;
+
+	wlc->pub->_ampdu = false;
+
+	if (on) {
+		if (!(wlc->pub->_n_enab & SUPPORT_11N)) {
+			brcms_err(core, "wl%d: driver not nmode enabled\n",
+				  wlc->pub->unit);
+			return -ENOTSUPP;
+		}
+		if (!brcms_c_ampdu_cap(ampdu)) {
+			brcms_err(core, "wl%d: device not ampdu capable\n",
+				  wlc->pub->unit);
+			return -ENOTSUPP;
+		}
+		wlc->pub->_ampdu = on;
+	}
+
+	return 0;
+}
+
+static void brcms_c_ffpld_init(struct ampdu_info *ampdu)
+{
+	int i, j;
+	struct brcms_fifo_info *fifo;
+
+	for (j = 0; j < NUM_FFPLD_FIFO; j++) {
+		fifo = (ampdu->fifo_tb + j);
+		fifo->ampdu_pld_size = 0;
+		for (i = 0; i <= FFPLD_MAX_MCS; i++)
+			fifo->mcs2ampdu_table[i] = 255;
+		fifo->dmaxferrate = 0;
+		fifo->accum_txampdu = 0;
+		fifo->prev_txfunfl = 0;
+		fifo->accum_txfunfl = 0;
+
+	}
+}
+
+struct ampdu_info *brcms_c_ampdu_attach(struct brcms_c_info *wlc)
+{
+	struct ampdu_info *ampdu;
+	int i;
+
+	ampdu = kzalloc(sizeof(struct ampdu_info), GFP_ATOMIC);
+	if (!ampdu)
+		return NULL;
+
+	ampdu->wlc = wlc;
+
+	for (i = 0; i < AMPDU_MAX_SCB_TID; i++)
+		ampdu->ini_enable[i] = true;
+	/* Disable ampdu for VO by default */
+	ampdu->ini_enable[PRIO_8021D_VO] = false;
+	ampdu->ini_enable[PRIO_8021D_NC] = false;
+
+	/* Disable ampdu for BK by default since not enough fifo space */
+	ampdu->ini_enable[PRIO_8021D_NONE] = false;
+	ampdu->ini_enable[PRIO_8021D_BK] = false;
+
+	ampdu->ba_tx_wsize = AMPDU_TX_BA_DEF_WSIZE;
+	ampdu->ba_rx_wsize = AMPDU_RX_BA_DEF_WSIZE;
+	ampdu->mpdu_density = AMPDU_DEF_MPDU_DENSITY;
+	ampdu->max_pdu = AUTO;
+	ampdu->dur = AMPDU_MAX_DUR;
+
+	ampdu->ffpld_rsvd = AMPDU_DEF_FFPLD_RSVD;
+	/*
+	 * bump max ampdu rcv size to 64k for all 11n
+	 * devices except 4321A0 and 4321A1
+	 */
+	if (BRCMS_ISNPHY(wlc->band) && NREV_LT(wlc->band->phyrev, 2))
+		ampdu->rx_factor = IEEE80211_HT_MAX_AMPDU_32K;
+	else
+		ampdu->rx_factor = IEEE80211_HT_MAX_AMPDU_64K;
+	ampdu->retry_limit = AMPDU_DEF_RETRY_LIMIT;
+	ampdu->rr_retry_limit = AMPDU_DEF_RR_RETRY_LIMIT;
+
+	for (i = 0; i < AMPDU_MAX_SCB_TID; i++) {
+		ampdu->retry_limit_tid[i] = ampdu->retry_limit;
+		ampdu->rr_retry_limit_tid[i] = ampdu->rr_retry_limit;
+	}
+
+	brcms_c_scb_ampdu_update_max_txlen(ampdu, ampdu->dur);
+	ampdu->mfbr = false;
+	/* try to set ampdu to the default value */
+	brcms_c_ampdu_set(ampdu, wlc->pub->_ampdu);
+
+	ampdu->tx_max_funl = FFPLD_TX_MAX_UNFL;
+	brcms_c_ffpld_init(ampdu);
+
+	return ampdu;
+}
+
+void brcms_c_ampdu_detach(struct ampdu_info *ampdu)
+{
+	kfree(ampdu);
+}
+
+static void brcms_c_scb_ampdu_update_config(struct ampdu_info *ampdu,
+					    struct scb *scb)
+{
+	struct scb_ampdu *scb_ampdu = &scb->scb_ampdu;
+	int i;
+
+	scb_ampdu->max_pdu = AMPDU_NUM_MPDU;
+
+	/* go back to legacy size if some preloading is occurring */
+	for (i = 0; i < NUM_FFPLD_FIFO; i++) {
+		if (ampdu->fifo_tb[i].ampdu_pld_size > FFPLD_PLD_INCR)
+			scb_ampdu->max_pdu = AMPDU_NUM_MPDU_LEGACY;
+	}
+
+	/* apply user override */
+	if (ampdu->max_pdu != AUTO)
+		scb_ampdu->max_pdu = (u8) ampdu->max_pdu;
+
+	scb_ampdu->release = min_t(u8, scb_ampdu->max_pdu,
+				   AMPDU_SCB_MAX_RELEASE);
+
+	if (scb_ampdu->max_rx_ampdu_bytes)
+		scb_ampdu->release = min_t(u8, scb_ampdu->release,
+			scb_ampdu->max_rx_ampdu_bytes / 1600);
+
+	scb_ampdu->release = min(scb_ampdu->release,
+				 ampdu->fifo_tb[TX_AC_BE_FIFO].
+				 mcs2ampdu_table[FFPLD_MAX_MCS]);
+}
+
+static void brcms_c_scb_ampdu_update_config_all(struct ampdu_info *ampdu)
+{
+	brcms_c_scb_ampdu_update_config(ampdu, &ampdu->wlc->pri_scb);
+}
+
+static void brcms_c_ffpld_calc_mcs2ampdu_table(struct ampdu_info *ampdu, int f)
+{
+	int i;
+	u32 phy_rate, dma_rate, tmp;
+	u8 max_mpdu;
+	struct brcms_fifo_info *fifo = (ampdu->fifo_tb + f);
+
+	/* recompute the dma rate */
+	/* note : we divide/multiply by 100 to avoid integer overflows */
+	max_mpdu = min_t(u8, fifo->mcs2ampdu_table[FFPLD_MAX_MCS],
+			 AMPDU_NUM_MPDU_LEGACY);
+	phy_rate = mcs_2_rate(FFPLD_MAX_MCS, true, false);
+	dma_rate =
+	    (((phy_rate / 100) *
+	      (max_mpdu * FFPLD_MPDU_SIZE - fifo->ampdu_pld_size))
+	     / (max_mpdu * FFPLD_MPDU_SIZE)) * 100;
+	fifo->dmaxferrate = dma_rate;
+
+	/* fill up the mcs2ampdu table; do not recalc the last mcs */
+	dma_rate = dma_rate >> 7;
+	for (i = 0; i < FFPLD_MAX_MCS; i++) {
+		/* shifting to keep it within integer range */
+		phy_rate = mcs_2_rate(i, true, false) >> 7;
+		if (phy_rate > dma_rate) {
+			tmp = ((fifo->ampdu_pld_size * phy_rate) /
+			       ((phy_rate - dma_rate) * FFPLD_MPDU_SIZE)) + 1;
+			tmp = min_t(u32, tmp, 255);
+			fifo->mcs2ampdu_table[i] = (u8) tmp;
+		}
+	}
+}
+
+/* evaluate the dma transfer rate using the tx underflows as feedback.
+ * If necessary, increase tx fifo preloading. If not enough,
+ * decrease maximum ampdu size for each mcs till underflows stop
+ * Return 1 if pre-loading not active, -1 if not an underflow event,
+ * 0 if pre-loading module took care of the event.
+ */
+static int brcms_c_ffpld_check_txfunfl(struct brcms_c_info *wlc, int fid)
+{
+	struct ampdu_info *ampdu = wlc->ampdu;
+	u32 phy_rate = mcs_2_rate(FFPLD_MAX_MCS, true, false);
+	u32 txunfl_ratio;
+	u8 max_mpdu;
+	u32 current_ampdu_cnt = 0;
+	u16 max_pld_size;
+	u32 new_txunfl;
+	struct brcms_fifo_info *fifo = (ampdu->fifo_tb + fid);
+	uint xmtfifo_sz;
+	u16 cur_txunfl;
+
+	/* return if we got here for a different reason than underflows */
+	cur_txunfl = brcms_b_read_shm(wlc->hw,
+				      M_UCODE_MACSTAT +
+				      offsetof(struct macstat, txfunfl[fid]));
+	new_txunfl = (u16) (cur_txunfl - fifo->prev_txfunfl);
+	if (new_txunfl == 0) {
+		brcms_dbg_ht(wlc->hw->d11core,
+			     "TX status FRAG set but no tx underflows\n");
+		return -1;
+	}
+	fifo->prev_txfunfl = cur_txunfl;
+
+	if (!ampdu->tx_max_funl)
+		return 1;
+
+	/* check if fifo is big enough */
+	if (brcms_b_xmtfifo_sz_get(wlc->hw, fid, &xmtfifo_sz))
+		return -1;
+
+	if ((TXFIFO_SIZE_UNIT * (u32) xmtfifo_sz) <= ampdu->ffpld_rsvd)
+		return 1;
+
+	max_pld_size = TXFIFO_SIZE_UNIT * xmtfifo_sz - ampdu->ffpld_rsvd;
+	fifo->accum_txfunfl += new_txunfl;
+
+	/* we need to wait for at least 10 underflows */
+	if (fifo->accum_txfunfl < 10)
+		return 0;
+
+	brcms_dbg_ht(wlc->hw->d11core, "ampdu_count %d  tx_underflows %d\n",
+		     current_ampdu_cnt, fifo->accum_txfunfl);
+
+	/*
+	   compute the current ratio of tx unfl per ampdu.
+	   When the current ampdu count becomes too
+	   big while the ratio remains small, we reset
+	   the current count in order to not
+	   introduce too big of a latency in detecting a
+	   large amount of tx underflows later.
+	 */
+
+	txunfl_ratio = current_ampdu_cnt / fifo->accum_txfunfl;
+
+	if (txunfl_ratio > ampdu->tx_max_funl) {
+		if (current_ampdu_cnt >= FFPLD_MAX_AMPDU_CNT)
+			fifo->accum_txfunfl = 0;
+
+		return 0;
+	}
+	max_mpdu = min_t(u8, fifo->mcs2ampdu_table[FFPLD_MAX_MCS],
+			 AMPDU_NUM_MPDU_LEGACY);
+
+	/* In case max value max_pdu is already lower than
+	   the fifo depth, there is nothing more we can do.
+	 */
+
+	if (fifo->ampdu_pld_size >= max_mpdu * FFPLD_MPDU_SIZE) {
+		fifo->accum_txfunfl = 0;
+		return 0;
+	}
+
+	if (fifo->ampdu_pld_size < max_pld_size) {
+
+		/* increment by TX_FIFO_PLD_INC bytes */
+		fifo->ampdu_pld_size += FFPLD_PLD_INCR;
+		if (fifo->ampdu_pld_size > max_pld_size)
+			fifo->ampdu_pld_size = max_pld_size;
+
+		/* update scb release size */
+		brcms_c_scb_ampdu_update_config_all(ampdu);
+
+		/*
+		 * compute a new dma xfer rate for max_mpdu @ max mcs.
+		 * This is the minimum dma rate that can achieve no
+		 * underflow condition for the current mpdu size.
+		 *
+		 * note : we divide/multiply by 100 to avoid integer overflows
+		 */
+		fifo->dmaxferrate =
+		    (((phy_rate / 100) *
+		      (max_mpdu * FFPLD_MPDU_SIZE - fifo->ampdu_pld_size))
+		     / (max_mpdu * FFPLD_MPDU_SIZE)) * 100;
+
+		brcms_dbg_ht(wlc->hw->d11core,
+			     "DMA estimated transfer rate %d; "
+			     "pre-load size %d\n",
+			     fifo->dmaxferrate, fifo->ampdu_pld_size);
+	} else {
+
+		/* decrease ampdu size */
+		if (fifo->mcs2ampdu_table[FFPLD_MAX_MCS] > 1) {
+			if (fifo->mcs2ampdu_table[FFPLD_MAX_MCS] == 255)
+				fifo->mcs2ampdu_table[FFPLD_MAX_MCS] =
+				    AMPDU_NUM_MPDU_LEGACY - 1;
+			else
+				fifo->mcs2ampdu_table[FFPLD_MAX_MCS] -= 1;
+
+			/* recompute the table */
+			brcms_c_ffpld_calc_mcs2ampdu_table(ampdu, fid);
+
+			/* update scb release size */
+			brcms_c_scb_ampdu_update_config_all(ampdu);
+		}
+	}
+	fifo->accum_txfunfl = 0;
+	return 0;
+}
+
+void
+brcms_c_ampdu_tx_operational(struct brcms_c_info *wlc, u8 tid,
+	u8 ba_wsize,		/* negotiated ba window size (in pdu) */
+	uint max_rx_ampdu_bytes) /* from ht_cap in beacon */
+{
+	struct scb_ampdu *scb_ampdu;
+	struct scb_ampdu_tid_ini *ini;
+	struct ampdu_info *ampdu = wlc->ampdu;
+	struct scb *scb = &wlc->pri_scb;
+	scb_ampdu = &scb->scb_ampdu;
+
+	if (!ampdu->ini_enable[tid]) {
+		brcms_err(wlc->hw->d11core, "%s: Rejecting tid %d\n",
+			  __func__, tid);
+		return;
+	}
+
+	ini = &scb_ampdu->ini[tid];
+	ini->tid = tid;
+	ini->scb = scb_ampdu->scb;
+	ini->ba_wsize = ba_wsize;
+	scb_ampdu->max_rx_ampdu_bytes = max_rx_ampdu_bytes;
+}
+
+void brcms_c_ampdu_reset_session(struct brcms_ampdu_session *session,
+				 struct brcms_c_info *wlc)
+{
+	session->wlc = wlc;
+	skb_queue_head_init(&session->skb_list);
+	session->max_ampdu_len = 0;    /* determined from first MPDU */
+	session->max_ampdu_frames = 0; /* determined from first MPDU */
+	session->ampdu_len = 0;
+	session->dma_len = 0;
+}
+
+/*
+ * Preps the given packet for AMPDU based on the session data. If the
+ * frame cannot be accomodated in the current session, -ENOSPC is
+ * returned.
+ */
+int brcms_c_ampdu_add_frame(struct brcms_ampdu_session *session,
+			    struct sk_buff *p)
+{
+	struct brcms_c_info *wlc = session->wlc;
+	struct ampdu_info *ampdu = wlc->ampdu;
+	struct scb *scb = &wlc->pri_scb;
+	struct scb_ampdu *scb_ampdu = &scb->scb_ampdu;
+	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(p);
+	struct ieee80211_tx_rate *txrate = tx_info->status.rates;
+	struct d11txh *txh = (struct d11txh *)p->data;
+	unsigned ampdu_frames;
+	u8 ndelim, tid;
+	u8 *plcp;
+	uint len;
+	u16 mcl;
+	bool fbr_iscck;
+	bool rr;
+
+	ndelim = txh->RTSPLCPFallback[AMPDU_FBR_NULL_DELIM];
+	plcp = (u8 *)(txh + 1);
+	fbr_iscck = !(le16_to_cpu(txh->XtraFrameTypes) & 0x03);
+	len = fbr_iscck ? BRCMS_GET_CCK_PLCP_LEN(txh->FragPLCPFallback) :
+			  BRCMS_GET_MIMO_PLCP_LEN(txh->FragPLCPFallback);
+	len = roundup(len, 4) + (ndelim + 1) * AMPDU_DELIMITER_LEN;
+
+	ampdu_frames = skb_queue_len(&session->skb_list);
+	if (ampdu_frames != 0) {
+		struct sk_buff *first;
+
+		if (ampdu_frames + 1 > session->max_ampdu_frames ||
+		    session->ampdu_len + len > session->max_ampdu_len)
+			return -ENOSPC;
+
+		/*
+		 * We aren't really out of space if the new frame is of
+		 * a different priority, but we want the same behaviour
+		 * so return -ENOSPC anyway.
+		 *
+		 * XXX: The old AMPDU code did this, but is it really
+		 * necessary?
+		 */
+		first = skb_peek(&session->skb_list);
+		if (p->priority != first->priority)
+			return -ENOSPC;
+	}
+
+	/*
+	 * Now that we're sure this frame can be accomodated, update the
+	 * session information.
+	 */
+	session->ampdu_len += len;
+	session->dma_len += p->len;
+
+	tid = (u8)p->priority;
+
+	/* Handle retry limits */
+	if (txrate[0].count <= ampdu->rr_retry_limit_tid[tid]) {
+		txrate[0].count++;
+		rr = true;
+	} else {
+		txrate[1].count++;
+		rr = false;
+	}
+
+	if (ampdu_frames == 0) {
+		u8 plcp0, plcp3, is40, sgi, mcs;
+		uint fifo = le16_to_cpu(txh->TxFrameID) & TXFID_QUEUE_MASK;
+		struct brcms_fifo_info *f = &ampdu->fifo_tb[fifo];
+
+		if (rr) {
+			plcp0 = plcp[0];
+			plcp3 = plcp[3];
+		} else {
+			plcp0 = txh->FragPLCPFallback[0];
+			plcp3 = txh->FragPLCPFallback[3];
+
+		}
+
+		/* Limit AMPDU size based on MCS */
+		is40 = (plcp0 & MIMO_PLCP_40MHZ) ? 1 : 0;
+		sgi = plcp3_issgi(plcp3) ? 1 : 0;
+		mcs = plcp0 & ~MIMO_PLCP_40MHZ;
+		session->max_ampdu_len = min(scb_ampdu->max_rx_ampdu_bytes,
+					     ampdu->max_txlen[mcs][is40][sgi]);
+
+		session->max_ampdu_frames = scb_ampdu->max_pdu;
+		if (mcs_2_rate(mcs, true, false) >= f->dmaxferrate) {
+			session->max_ampdu_frames =
+				min_t(u16, f->mcs2ampdu_table[mcs],
+				      session->max_ampdu_frames);
+		}
+	}
+
+	/*
+	 * Treat all frames as "middle" frames of AMPDU here. First and
+	 * last frames must be fixed up after all MPDUs have been prepped.
+	 */
+	mcl = le16_to_cpu(txh->MacTxControlLow);
+	mcl &= ~TXC_AMPDU_MASK;
+	mcl |= (TXC_AMPDU_MIDDLE << TXC_AMPDU_SHIFT);
+	mcl &= ~(TXC_STARTMSDU | TXC_SENDRTS | TXC_SENDCTS);
+	txh->MacTxControlLow = cpu_to_le16(mcl);
+	txh->PreloadSize = 0;	/* always default to 0 */
+
+	skb_queue_tail(&session->skb_list, p);
+
+	return 0;
+}
+
+void brcms_c_ampdu_finalize(struct brcms_ampdu_session *session)
+{
+	struct brcms_c_info *wlc = session->wlc;
+	struct ampdu_info *ampdu = wlc->ampdu;
+	struct sk_buff *first, *last;
+	struct d11txh *txh;
+	struct ieee80211_tx_info *tx_info;
+	struct ieee80211_tx_rate *txrate;
+	u8 ndelim;
+	u8 *plcp;
+	uint len;
+	uint fifo;
+	struct brcms_fifo_info *f;
+	u16 mcl;
+	bool fbr;
+	bool fbr_iscck;
+	struct ieee80211_rts *rts;
+	bool use_rts = false, use_cts = false;
+	u16 dma_len = session->dma_len;
+	u16 mimo_ctlchbw = PHY_TXC1_BW_20MHZ;
+	u32 rspec = 0, rspec_fallback = 0;
+	u32 rts_rspec = 0, rts_rspec_fallback = 0;
+	u8 plcp0, is40, mcs;
+	u16 mch;
+	u8 preamble_type = BRCMS_GF_PREAMBLE;
+	u8 fbr_preamble_type = BRCMS_GF_PREAMBLE;
+	u8 rts_preamble_type = BRCMS_LONG_PREAMBLE;
+	u8 rts_fbr_preamble_type = BRCMS_LONG_PREAMBLE;
+
+	if (skb_queue_empty(&session->skb_list))
+		return;
+
+	first = skb_peek(&session->skb_list);
+	last = skb_peek_tail(&session->skb_list);
+
+	/* Need to fix up last MPDU first to adjust AMPDU length */
+	txh = (struct d11txh *)last->data;
+	fifo = le16_to_cpu(txh->TxFrameID) & TXFID_QUEUE_MASK;
+	f = &ampdu->fifo_tb[fifo];
+
+	mcl = le16_to_cpu(txh->MacTxControlLow);
+	mcl &= ~TXC_AMPDU_MASK;
+	mcl |= (TXC_AMPDU_LAST << TXC_AMPDU_SHIFT);
+	txh->MacTxControlLow = cpu_to_le16(mcl);
+
+	/* remove the null delimiter after last mpdu */
+	ndelim = txh->RTSPLCPFallback[AMPDU_FBR_NULL_DELIM];
+	txh->RTSPLCPFallback[AMPDU_FBR_NULL_DELIM] = 0;
+	session->ampdu_len -= ndelim * AMPDU_DELIMITER_LEN;
+
+	/* remove the pad len from last mpdu */
+	fbr_iscck = ((le16_to_cpu(txh->XtraFrameTypes) & 0x3) == 0);
+	len = fbr_iscck ? BRCMS_GET_CCK_PLCP_LEN(txh->FragPLCPFallback) :
+			  BRCMS_GET_MIMO_PLCP_LEN(txh->FragPLCPFallback);
+	session->ampdu_len -= roundup(len, 4) - len;
+
+	/* Now fix up the first MPDU */
+	tx_info = IEEE80211_SKB_CB(first);
+	txrate = tx_info->status.rates;
+	txh = (struct d11txh *)first->data;
+	plcp = (u8 *)(txh + 1);
+	rts = (struct ieee80211_rts *)&txh->rts_frame;
+
+	mcl = le16_to_cpu(txh->MacTxControlLow);
+	/* If only one MPDU leave it marked as last */
+	if (first != last) {
+		mcl &= ~TXC_AMPDU_MASK;
+		mcl |= (TXC_AMPDU_FIRST << TXC_AMPDU_SHIFT);
+	}
+	mcl |= TXC_STARTMSDU;
+	if (ieee80211_is_rts(rts->frame_control)) {
+		mcl |= TXC_SENDRTS;
+		use_rts = true;
+	}
+	if (ieee80211_is_cts(rts->frame_control)) {
+		mcl |= TXC_SENDCTS;
+		use_cts = true;
+	}
+	txh->MacTxControlLow = cpu_to_le16(mcl);
+
+	fbr = txrate[1].count > 0;
+	if (!fbr)
+		plcp0 = plcp[0];
+	else
+		plcp0 = txh->FragPLCPFallback[0];
+
+	is40 = (plcp0 & MIMO_PLCP_40MHZ) ? 1 : 0;
+	mcs = plcp0 & ~MIMO_PLCP_40MHZ;
+
+	if (is40) {
+		if (CHSPEC_SB_UPPER(wlc_phy_chanspec_get(wlc->band->pi)))
+			mimo_ctlchbw = PHY_TXC1_BW_20MHZ_UP;
+		else
+			mimo_ctlchbw = PHY_TXC1_BW_20MHZ;
+	}
+
+	/* rebuild the rspec and rspec_fallback */
+	rspec = RSPEC_MIMORATE;
+	rspec |= plcp[0] & ~MIMO_PLCP_40MHZ;
+	if (plcp[0] & MIMO_PLCP_40MHZ)
+		rspec |= (PHY_TXC1_BW_40MHZ << RSPEC_BW_SHIFT);
+
+	fbr_iscck = !(le16_to_cpu(txh->XtraFrameTypes) & 0x03);
+	if (fbr_iscck) {
+		rspec_fallback =
+			cck_rspec(cck_phy2mac_rate(txh->FragPLCPFallback[0]));
+	} else {
+		rspec_fallback = RSPEC_MIMORATE;
+		rspec_fallback |= txh->FragPLCPFallback[0] & ~MIMO_PLCP_40MHZ;
+		if (txh->FragPLCPFallback[0] & MIMO_PLCP_40MHZ)
+			rspec_fallback |= PHY_TXC1_BW_40MHZ << RSPEC_BW_SHIFT;
+	}
+
+	if (use_rts || use_cts) {
+		rts_rspec =
+			brcms_c_rspec_to_rts_rspec(wlc, rspec,
+						   false, mimo_ctlchbw);
+		rts_rspec_fallback =
+			brcms_c_rspec_to_rts_rspec(wlc, rspec_fallback,
+						   false, mimo_ctlchbw);
+	}
+
+	BRCMS_SET_MIMO_PLCP_LEN(plcp, session->ampdu_len);
+	/* mark plcp to indicate ampdu */
+	BRCMS_SET_MIMO_PLCP_AMPDU(plcp);
+
+	/* reset the mixed mode header durations */
+	if (txh->MModeLen) {
+		u16 mmodelen = brcms_c_calc_lsig_len(wlc, rspec,
+						     session->ampdu_len);
+		txh->MModeLen = cpu_to_le16(mmodelen);
+		preamble_type = BRCMS_MM_PREAMBLE;
+	}
+	if (txh->MModeFbrLen) {
+		u16 mmfbrlen = brcms_c_calc_lsig_len(wlc, rspec_fallback,
+						     session->ampdu_len);
+		txh->MModeFbrLen = cpu_to_le16(mmfbrlen);
+		fbr_preamble_type = BRCMS_MM_PREAMBLE;
+	}
+
+	/* set the preload length */
+	if (mcs_2_rate(mcs, true, false) >= f->dmaxferrate) {
+		dma_len = min(dma_len, f->ampdu_pld_size);
+		txh->PreloadSize = cpu_to_le16(dma_len);
+	} else {
+		txh->PreloadSize = 0;
+	}
+
+	mch = le16_to_cpu(txh->MacTxControlHigh);
+
+	/* update RTS dur fields */
+	if (use_rts || use_cts) {
+		u16 durid;
+		if ((mch & TXC_PREAMBLE_RTS_MAIN_SHORT) ==
+		    TXC_PREAMBLE_RTS_MAIN_SHORT)
+			rts_preamble_type = BRCMS_SHORT_PREAMBLE;
+
+		if ((mch & TXC_PREAMBLE_RTS_FB_SHORT) ==
+		     TXC_PREAMBLE_RTS_FB_SHORT)
+			rts_fbr_preamble_type = BRCMS_SHORT_PREAMBLE;
+
+		durid = brcms_c_compute_rtscts_dur(wlc, use_cts, rts_rspec,
+						   rspec, rts_preamble_type,
+						   preamble_type,
+						   session->ampdu_len, true);
+		rts->duration = cpu_to_le16(durid);
+		durid = brcms_c_compute_rtscts_dur(wlc, use_cts,
+						   rts_rspec_fallback,
+						   rspec_fallback,
+						   rts_fbr_preamble_type,
+						   fbr_preamble_type,
+						   session->ampdu_len, true);
+		txh->RTSDurFallback = cpu_to_le16(durid);
+		/* set TxFesTimeNormal */
+		txh->TxFesTimeNormal = rts->duration;
+		/* set fallback rate version of TxFesTimeNormal */
+		txh->TxFesTimeFallback = txh->RTSDurFallback;
+	}
+
+	/* set flag and plcp for fallback rate */
+	if (fbr) {
+		mch |= TXC_AMPDU_FBR;
+		txh->MacTxControlHigh = cpu_to_le16(mch);
+		BRCMS_SET_MIMO_PLCP_AMPDU(plcp);
+		BRCMS_SET_MIMO_PLCP_AMPDU(txh->FragPLCPFallback);
+	}
+
+	brcms_dbg_ht(wlc->hw->d11core, "wl%d: count %d ampdu_len %d\n",
+		     wlc->pub->unit, skb_queue_len(&session->skb_list),
+		     session->ampdu_len);
+}
+
+static void
+brcms_c_ampdu_rate_status(struct brcms_c_info *wlc,
+			  struct ieee80211_tx_info *tx_info,
+			  struct tx_status *txs, u8 mcs)
+{
+	struct ieee80211_tx_rate *txrate = tx_info->status.rates;
+	int i;
+
+	/* clear the rest of the rates */
+	for (i = 2; i < IEEE80211_TX_MAX_RATES; i++) {
+		txrate[i].idx = -1;
+		txrate[i].count = 0;
+	}
+}
+
+static void
+brcms_c_ampdu_dotxstatus_complete(struct ampdu_info *ampdu, struct scb *scb,
+			      struct sk_buff *p, struct tx_status *txs,
+			      u32 s1, u32 s2)
+{
+	struct scb_ampdu *scb_ampdu;
+	struct brcms_c_info *wlc = ampdu->wlc;
+	struct scb_ampdu_tid_ini *ini;
+	u8 bitmap[8], queue, tid;
+	struct d11txh *txh;
+	u8 *plcp;
+	struct ieee80211_hdr *h;
+	u16 seq, start_seq = 0, bindex, index, mcl;
+	u8 mcs = 0;
+	bool ba_recd = false, ack_recd = false;
+	u8 suc_mpdu = 0, tot_mpdu = 0;
+	uint supr_status;
+	bool retry = true;
+	u16 mimoantsel = 0;
+	u8 retry_limit;
+	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(p);
+
+#ifdef DEBUG
+	u8 hole[AMPDU_MAX_MPDU];
+	memset(hole, 0, sizeof(hole));
+#endif
+
+	scb_ampdu = &scb->scb_ampdu;
+	tid = (u8) (p->priority);
+
+	ini = &scb_ampdu->ini[tid];
+	retry_limit = ampdu->retry_limit_tid[tid];
+	memset(bitmap, 0, sizeof(bitmap));
+	queue = txs->frameid & TXFID_QUEUE_MASK;
+	supr_status = txs->status & TX_STATUS_SUPR_MASK;
+
+	if (txs->status & TX_STATUS_ACK_RCV) {
+		WARN_ON(!(txs->status & TX_STATUS_INTERMEDIATE));
+		start_seq = txs->sequence >> SEQNUM_SHIFT;
+		bitmap[0] = (txs->status & TX_STATUS_BA_BMAP03_MASK) >>
+		    TX_STATUS_BA_BMAP03_SHIFT;
+
+		WARN_ON(s1 & TX_STATUS_INTERMEDIATE);
+		WARN_ON(!(s1 & TX_STATUS_AMPDU));
+
+		bitmap[0] |=
+		    (s1 & TX_STATUS_BA_BMAP47_MASK) <<
+		    TX_STATUS_BA_BMAP47_SHIFT;
+		bitmap[1] = (s1 >> 8) & 0xff;
+		bitmap[2] = (s1 >> 16) & 0xff;
+		bitmap[3] = (s1 >> 24) & 0xff;
+
+		bitmap[4] = s2 & 0xff;
+		bitmap[5] = (s2 >> 8) & 0xff;
+		bitmap[6] = (s2 >> 16) & 0xff;
+		bitmap[7] = (s2 >> 24) & 0xff;
+
+		ba_recd = true;
+	} else {
+		if (supr_status) {
+			if (supr_status == TX_STATUS_SUPR_BADCH) {
+				brcms_dbg_ht(wlc->hw->d11core,
+					  "%s: Pkt tx suppressed, illegal channel possibly %d\n",
+					  __func__, CHSPEC_CHANNEL(
+					  wlc->default_bss->chanspec));
+			} else {
+				if (supr_status != TX_STATUS_SUPR_FRAG)
+					brcms_err(wlc->hw->d11core,
+						  "%s: supr_status 0x%x\n",
+						  __func__, supr_status);
+			}
+			/* no need to retry for badch; will fail again */
+			if (supr_status == TX_STATUS_SUPR_BADCH ||
+			    supr_status == TX_STATUS_SUPR_EXPTIME) {
+				retry = false;
+			} else if (supr_status == TX_STATUS_SUPR_EXPTIME) {
+				/* TX underflow:
+				 *   try tuning pre-loading or ampdu size
+				 */
+			} else if (supr_status == TX_STATUS_SUPR_FRAG) {
+				/*
+				 * if there were underflows, but pre-loading
+				 * is not active, notify rate adaptation.
+				 */
+				brcms_c_ffpld_check_txfunfl(wlc, queue);
+			}
+		} else if (txs->phyerr) {
+			brcms_dbg_ht(wlc->hw->d11core,
+				     "%s: ampdu tx phy error (0x%x)\n",
+				     __func__, txs->phyerr);
+		}
+	}
+
+	/* loop through all pkts and retry if not acked */
+	while (p) {
+		tx_info = IEEE80211_SKB_CB(p);
+		txh = (struct d11txh *) p->data;
+		mcl = le16_to_cpu(txh->MacTxControlLow);
+		plcp = (u8 *) (txh + 1);
+		h = (struct ieee80211_hdr *)(plcp + D11_PHY_HDR_LEN);
+		seq = le16_to_cpu(h->seq_ctrl) >> SEQNUM_SHIFT;
+
+		trace_brcms_txdesc(&wlc->hw->d11core->dev, txh, sizeof(*txh));
+
+		if (tot_mpdu == 0) {
+			mcs = plcp[0] & MIMO_PLCP_MCS_MASK;
+			mimoantsel = le16_to_cpu(txh->ABI_MimoAntSel);
+		}
+
+		index = TX_SEQ_TO_INDEX(seq);
+		ack_recd = false;
+		if (ba_recd) {
+			bindex = MODSUB_POW2(seq, start_seq, SEQNUM_MAX);
+			brcms_dbg_ht(wlc->hw->d11core,
+				     "tid %d seq %d, start_seq %d, bindex %d set %d, index %d\n",
+				     tid, seq, start_seq, bindex,
+				     isset(bitmap, bindex), index);
+			/* if acked then clear bit and free packet */
+			if ((bindex < AMPDU_TX_BA_MAX_WSIZE)
+			    && isset(bitmap, bindex)) {
+				ini->txretry[index] = 0;
+
+				/*
+				 * ampdu_ack_len:
+				 *   number of acked aggregated frames
+				 */
+				/* ampdu_len: number of aggregated frames */
+				brcms_c_ampdu_rate_status(wlc, tx_info, txs,
+							  mcs);
+				tx_info->flags |= IEEE80211_TX_STAT_ACK;
+				tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
+				tx_info->status.ampdu_ack_len =
+					tx_info->status.ampdu_len = 1;
+
+				skb_pull(p, D11_PHY_HDR_LEN);
+				skb_pull(p, D11_TXH_LEN);
+
+				ieee80211_tx_status_irqsafe(wlc->pub->ieee_hw,
+							    p);
+				ack_recd = true;
+				suc_mpdu++;
+			}
+		}
+		/* either retransmit or send bar if ack not recd */
+		if (!ack_recd) {
+			if (retry && (ini->txretry[index] < (int)retry_limit)) {
+				int ret;
+				ini->txretry[index]++;
+				ret = brcms_c_txfifo(wlc, queue, p);
+				/*
+				 * We shouldn't be out of space in the DMA
+				 * ring here since we're reinserting a frame
+				 * that was just pulled out.
+				 */
+				WARN_ONCE(ret, "queue %d out of txds\n", queue);
+			} else {
+				/* Retry timeout */
+				ieee80211_tx_info_clear_status(tx_info);
+				tx_info->status.ampdu_ack_len = 0;
+				tx_info->status.ampdu_len = 1;
+				tx_info->flags |=
+				    IEEE80211_TX_STAT_AMPDU_NO_BACK;
+				skb_pull(p, D11_PHY_HDR_LEN);
+				skb_pull(p, D11_TXH_LEN);
+				brcms_dbg_ht(wlc->hw->d11core,
+					     "BA Timeout, seq %d\n",
+					     seq);
+				ieee80211_tx_status_irqsafe(wlc->pub->ieee_hw,
+							    p);
+			}
+		}
+		tot_mpdu++;
+
+		/* break out if last packet of ampdu */
+		if (((mcl & TXC_AMPDU_MASK) >> TXC_AMPDU_SHIFT) ==
+		    TXC_AMPDU_LAST)
+			break;
+
+		p = dma_getnexttxp(wlc->hw->di[queue], DMA_RANGE_TRANSMITTED);
+	}
+
+	/* update rate state */
+	brcms_c_antsel_antsel2id(wlc->asi, mimoantsel);
+}
+
+void
+brcms_c_ampdu_dotxstatus(struct ampdu_info *ampdu, struct scb *scb,
+		     struct sk_buff *p, struct tx_status *txs)
+{
+	struct brcms_c_info *wlc = ampdu->wlc;
+	u32 s1 = 0, s2 = 0;
+
+	/* BMAC_NOTE: For the split driver, second level txstatus comes later
+	 * So if the ACK was received then wait for the second level else just
+	 * call the first one
+	 */
+	if (txs->status & TX_STATUS_ACK_RCV) {
+		u8 status_delay = 0;
+
+		/* wait till the next 8 bytes of txstatus is available */
+		s1 = bcma_read32(wlc->hw->d11core, D11REGOFFS(frmtxstatus));
+		while ((s1 & TXS_V) == 0) {
+			udelay(1);
+			status_delay++;
+			if (status_delay > 10)
+				return; /* error condition */
+			s1 = bcma_read32(wlc->hw->d11core,
+					 D11REGOFFS(frmtxstatus));
+		}
+
+		s2 = bcma_read32(wlc->hw->d11core, D11REGOFFS(frmtxstatus2));
+	}
+
+	if (scb) {
+		brcms_c_ampdu_dotxstatus_complete(ampdu, scb, p, txs, s1, s2);
+	} else {
+		/* loop through all pkts and free */
+		u8 queue = txs->frameid & TXFID_QUEUE_MASK;
+		struct d11txh *txh;
+		u16 mcl;
+		while (p) {
+			txh = (struct d11txh *) p->data;
+			trace_brcms_txdesc(&wlc->hw->d11core->dev, txh,
+					   sizeof(*txh));
+			mcl = le16_to_cpu(txh->MacTxControlLow);
+			brcmu_pkt_buf_free_skb(p);
+			/* break out if last packet of ampdu */
+			if (((mcl & TXC_AMPDU_MASK) >> TXC_AMPDU_SHIFT) ==
+			    TXC_AMPDU_LAST)
+				break;
+			p = dma_getnexttxp(wlc->hw->di[queue],
+					   DMA_RANGE_TRANSMITTED);
+		}
+	}
+}
+
+void brcms_c_ampdu_macaddr_upd(struct brcms_c_info *wlc)
+{
+	char template[T_RAM_ACCESS_SZ * 2];
+
+	/* driver needs to write the ta in the template; ta is at offset 16 */
+	memset(template, 0, sizeof(template));
+	memcpy(template, wlc->pub->cur_etheraddr, ETH_ALEN);
+	brcms_b_write_template_ram(wlc->hw, (T_BA_TPL_BASE + 16),
+				  (T_RAM_ACCESS_SZ * 2),
+				  template);
+}
+
+bool brcms_c_aggregatable(struct brcms_c_info *wlc, u8 tid)
+{
+	return wlc->ampdu->ini_enable[tid];
+}
+
+void brcms_c_ampdu_shm_upd(struct ampdu_info *ampdu)
+{
+	struct brcms_c_info *wlc = ampdu->wlc;
+
+	/*
+	 * Extend ucode internal watchdog timer to
+	 * match larger received frames
+	 */
+	if ((ampdu->rx_factor & IEEE80211_HT_AMPDU_PARM_FACTOR) ==
+	    IEEE80211_HT_MAX_AMPDU_64K) {
+		brcms_b_write_shm(wlc->hw, M_MIMO_MAXSYM, MIMO_MAXSYM_MAX);
+		brcms_b_write_shm(wlc->hw, M_WATCHDOG_8TU, WATCHDOG_8TU_MAX);
+	} else {
+		brcms_b_write_shm(wlc->hw, M_MIMO_MAXSYM, MIMO_MAXSYM_DEF);
+		brcms_b_write_shm(wlc->hw, M_WATCHDOG_8TU, WATCHDOG_8TU_DEF);
+	}
+}
+
+/*
+ * callback function that helps invalidating ampdu packets in a DMA queue
+ */
+static void dma_cb_fn_ampdu(void *txi, void *arg_a)
+{
+	struct ieee80211_sta *sta = arg_a;
+	struct ieee80211_tx_info *tx_info = (struct ieee80211_tx_info *)txi;
+
+	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) &&
+	    (tx_info->rate_driver_data[0] == sta || sta == NULL))
+		tx_info->rate_driver_data[0] = NULL;
+}
+
+/*
+ * When a remote party is no longer available for ampdu communication, any
+ * pending tx ampdu packets in the driver have to be flushed.
+ */
+void brcms_c_ampdu_flush(struct brcms_c_info *wlc,
+		     struct ieee80211_sta *sta, u16 tid)
+{
+	brcms_c_inval_dma_pkts(wlc->hw, sta, dma_cb_fn_ampdu);
+}