iwlwifi: split the drivers for agn and legacy devices 3945/4965

Intel WiFi devices 3945 and 4965 now have their own driver in the folder

	drivers/net/wireless/iwlegacy

Add support to build these drivers independently of the driver for
AGN devices. Selecting the 3945 builds iwl3945.ko and iwl_legacy.ko,
and selecting the 4965 builds iwl4965.ko and iwl_legacy.ko. iwl-legacy.ko
contains code shared between both devices.

The 3945 is an ABG/BG device, with no support for 802.11n. The 4965 is a 2x3
ABGN device.

Signed-off-by: Meenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Acked-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>

1 files changed, 1359 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlegacy/iwl-4965-tx.c b/drivers/net/wireless/iwlegacy/iwl-4965-tx.c
new file mode 100644
index 00000000000..2e0f0dbf87e
--- /dev/null
+++ b/drivers/net/wireless/iwlegacy/iwl-4965-tx.c
@@ -0,0 +1,1359 @@
+/******************************************************************************
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
+ * USA
+ *
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * Contact Information:
+ *  Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+
+#include "iwl-dev.h"
+#include "iwl-core.h"
+#include "iwl-sta.h"
+#include "iwl-io.h"
+#include "iwl-helpers.h"
+#include "iwl-4965-hw.h"
+#include "iwl-4965.h"
+
+/*
+ * mac80211 queues, ACs, hardware queues, FIFOs.
+ *
+ * Cf. http://wireless.kernel.org/en/developers/Documentation/mac80211/queues
+ *
+ * Mac80211 uses the following numbers, which we get as from it
+ * by way of skb_get_queue_mapping(skb):
+ *
+ *	VO	0
+ *	VI	1
+ *	BE	2
+ *	BK	3
+ *
+ *
+ * Regular (not A-MPDU) frames are put into hardware queues corresponding
+ * to the FIFOs, see comments in iwl-prph.h. Aggregated frames get their
+ * own queue per aggregation session (RA/TID combination), such queues are
+ * set up to map into FIFOs too, for which we need an AC->FIFO mapping. In
+ * order to map frames to the right queue, we also need an AC->hw queue
+ * mapping. This is implemented here.
+ *
+ * Due to the way hw queues are set up (by the hw specific modules like
+ * iwl-4965.c), the AC->hw queue mapping is the identity
+ * mapping.
+ */
+
+static const u8 tid_to_ac[] = {
+	IEEE80211_AC_BE,
+	IEEE80211_AC_BK,
+	IEEE80211_AC_BK,
+	IEEE80211_AC_BE,
+	IEEE80211_AC_VI,
+	IEEE80211_AC_VI,
+	IEEE80211_AC_VO,
+	IEEE80211_AC_VO
+};
+
+static inline int iwl4965_get_ac_from_tid(u16 tid)
+{
+	if (likely(tid < ARRAY_SIZE(tid_to_ac)))
+		return tid_to_ac[tid];
+
+	/* no support for TIDs 8-15 yet */
+	return -EINVAL;
+}
+
+static inline int
+iwl4965_get_fifo_from_tid(struct iwl_rxon_context *ctx, u16 tid)
+{
+	if (likely(tid < ARRAY_SIZE(tid_to_ac)))
+		return ctx->ac_to_fifo[tid_to_ac[tid]];
+
+	/* no support for TIDs 8-15 yet */
+	return -EINVAL;
+}
+
+/*
+ * handle build REPLY_TX command notification.
+ */
+static void iwl4965_tx_cmd_build_basic(struct iwl_priv *priv,
+					struct sk_buff *skb,
+					struct iwl_tx_cmd *tx_cmd,
+					struct ieee80211_tx_info *info,
+					struct ieee80211_hdr *hdr,
+					u8 std_id)
+{
+	__le16 fc = hdr->frame_control;
+	__le32 tx_flags = tx_cmd->tx_flags;
+
+	tx_cmd->stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;
+	if (!(info->flags & IEEE80211_TX_CTL_NO_ACK)) {
+		tx_flags |= TX_CMD_FLG_ACK_MSK;
+		if (ieee80211_is_mgmt(fc))
+			tx_flags |= TX_CMD_FLG_SEQ_CTL_MSK;
+		if (ieee80211_is_probe_resp(fc) &&
+		    !(le16_to_cpu(hdr->seq_ctrl) & 0xf))
+			tx_flags |= TX_CMD_FLG_TSF_MSK;
+	} else {
+		tx_flags &= (~TX_CMD_FLG_ACK_MSK);
+		tx_flags |= TX_CMD_FLG_SEQ_CTL_MSK;
+	}
+
+	if (ieee80211_is_back_req(fc))
+		tx_flags |= TX_CMD_FLG_ACK_MSK | TX_CMD_FLG_IMM_BA_RSP_MASK;
+
+	tx_cmd->sta_id = std_id;
+	if (ieee80211_has_morefrags(fc))
+		tx_flags |= TX_CMD_FLG_MORE_FRAG_MSK;
+
+	if (ieee80211_is_data_qos(fc)) {
+		u8 *qc = ieee80211_get_qos_ctl(hdr);
+		tx_cmd->tid_tspec = qc[0] & 0xf;
+		tx_flags &= ~TX_CMD_FLG_SEQ_CTL_MSK;
+	} else {
+		tx_flags |= TX_CMD_FLG_SEQ_CTL_MSK;
+	}
+
+	iwl_legacy_tx_cmd_protection(priv, info, fc, &tx_flags);
+
+	tx_flags &= ~(TX_CMD_FLG_ANT_SEL_MSK);
+	if (ieee80211_is_mgmt(fc)) {
+		if (ieee80211_is_assoc_req(fc) || ieee80211_is_reassoc_req(fc))
+			tx_cmd->timeout.pm_frame_timeout = cpu_to_le16(3);
+		else
+			tx_cmd->timeout.pm_frame_timeout = cpu_to_le16(2);
+	} else {
+		tx_cmd->timeout.pm_frame_timeout = 0;
+	}
+
+	tx_cmd->driver_txop = 0;
+	tx_cmd->tx_flags = tx_flags;
+	tx_cmd->next_frame_len = 0;
+}
+
+#define RTS_DFAULT_RETRY_LIMIT		60
+
+static void iwl4965_tx_cmd_build_rate(struct iwl_priv *priv,
+			      struct iwl_tx_cmd *tx_cmd,
+			      struct ieee80211_tx_info *info,
+			      __le16 fc)
+{
+	u32 rate_flags;
+	int rate_idx;
+	u8 rts_retry_limit;
+	u8 data_retry_limit;
+	u8 rate_plcp;
+
+	/* Set retry limit on DATA packets and Probe Responses*/
+	if (ieee80211_is_probe_resp(fc))
+		data_retry_limit = 3;
+	else
+		data_retry_limit = IWL4965_DEFAULT_TX_RETRY;
+	tx_cmd->data_retry_limit = data_retry_limit;
+
+	/* Set retry limit on RTS packets */
+	rts_retry_limit = RTS_DFAULT_RETRY_LIMIT;
+	if (data_retry_limit < rts_retry_limit)
+		rts_retry_limit = data_retry_limit;
+	tx_cmd->rts_retry_limit = rts_retry_limit;
+
+	/* DATA packets will use the uCode station table for rate/antenna
+	 * selection */
+	if (ieee80211_is_data(fc)) {
+		tx_cmd->initial_rate_index = 0;
+		tx_cmd->tx_flags |= TX_CMD_FLG_STA_RATE_MSK;
+		return;
+	}
+
+	/**
+	 * If the current TX rate stored in mac80211 has the MCS bit set, it's
+	 * not really a TX rate.  Thus, we use the lowest supported rate for
+	 * this band.  Also use the lowest supported rate if the stored rate
+	 * index is invalid.
+	 */
+	rate_idx = info->control.rates[0].idx;
+	if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS ||
+			(rate_idx < 0) || (rate_idx > IWL_RATE_COUNT_LEGACY))
+		rate_idx = rate_lowest_index(&priv->bands[info->band],
+				info->control.sta);
+	/* For 5 GHZ band, remap mac80211 rate indices into driver indices */
+	if (info->band == IEEE80211_BAND_5GHZ)
+		rate_idx += IWL_FIRST_OFDM_RATE;
+	/* Get PLCP rate for tx_cmd->rate_n_flags */
+	rate_plcp = iwl_rates[rate_idx].plcp;
+	/* Zero out flags for this packet */
+	rate_flags = 0;
+
+	/* Set CCK flag as needed */
+	if ((rate_idx >= IWL_FIRST_CCK_RATE) && (rate_idx <= IWL_LAST_CCK_RATE))
+		rate_flags |= RATE_MCS_CCK_MSK;
+
+	/* Set up antennas */
+	priv->mgmt_tx_ant = iwl4965_toggle_tx_ant(priv, priv->mgmt_tx_ant,
+				      priv->hw_params.valid_tx_ant);
+
+	rate_flags |= iwl4965_ant_idx_to_flags(priv->mgmt_tx_ant);
+
+	/* Set the rate in the TX cmd */
+	tx_cmd->rate_n_flags = iwl4965_hw_set_rate_n_flags(rate_plcp, rate_flags);
+}
+
+static void iwl4965_tx_cmd_build_hwcrypto(struct iwl_priv *priv,
+				      struct ieee80211_tx_info *info,
+				      struct iwl_tx_cmd *tx_cmd,
+				      struct sk_buff *skb_frag,
+				      int sta_id)
+{
+	struct ieee80211_key_conf *keyconf = info->control.hw_key;
+
+	switch (keyconf->cipher) {
+	case WLAN_CIPHER_SUITE_CCMP:
+		tx_cmd->sec_ctl = TX_CMD_SEC_CCM;
+		memcpy(tx_cmd->key, keyconf->key, keyconf->keylen);
+		if (info->flags & IEEE80211_TX_CTL_AMPDU)
+			tx_cmd->tx_flags |= TX_CMD_FLG_AGG_CCMP_MSK;
+		IWL_DEBUG_TX(priv, "tx_cmd with AES hwcrypto\n");
+		break;
+
+	case WLAN_CIPHER_SUITE_TKIP:
+		tx_cmd->sec_ctl = TX_CMD_SEC_TKIP;
+		ieee80211_get_tkip_key(keyconf, skb_frag,
+			IEEE80211_TKIP_P2_KEY, tx_cmd->key);
+		IWL_DEBUG_TX(priv, "tx_cmd with tkip hwcrypto\n");
+		break;
+
+	case WLAN_CIPHER_SUITE_WEP104:
+		tx_cmd->sec_ctl |= TX_CMD_SEC_KEY128;
+		/* fall through */
+	case WLAN_CIPHER_SUITE_WEP40:
+		tx_cmd->sec_ctl |= (TX_CMD_SEC_WEP |
+			(keyconf->keyidx & TX_CMD_SEC_MSK) << TX_CMD_SEC_SHIFT);
+
+		memcpy(&tx_cmd->key[3], keyconf->key, keyconf->keylen);
+
+		IWL_DEBUG_TX(priv, "Configuring packet for WEP encryption "
+			     "with key %d\n", keyconf->keyidx);
+		break;
+
+	default:
+		IWL_ERR(priv, "Unknown encode cipher %x\n", keyconf->cipher);
+		break;
+	}
+}
+
+/*
+ * start REPLY_TX command process
+ */
+int iwl4965_tx_skb(struct iwl_priv *priv, struct sk_buff *skb)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+	struct ieee80211_sta *sta = info->control.sta;
+	struct iwl_station_priv *sta_priv = NULL;
+	struct iwl_tx_queue *txq;
+	struct iwl_queue *q;
+	struct iwl_device_cmd *out_cmd;
+	struct iwl_cmd_meta *out_meta;
+	struct iwl_tx_cmd *tx_cmd;
+	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
+	int txq_id;
+	dma_addr_t phys_addr;
+	dma_addr_t txcmd_phys;
+	dma_addr_t scratch_phys;
+	u16 len, firstlen, secondlen;
+	u16 seq_number = 0;
+	__le16 fc;
+	u8 hdr_len;
+	u8 sta_id;
+	u8 wait_write_ptr = 0;
+	u8 tid = 0;
+	u8 *qc = NULL;
+	unsigned long flags;
+	bool is_agg = false;
+
+	if (info->control.vif)
+		ctx = iwl_legacy_rxon_ctx_from_vif(info->control.vif);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (iwl_legacy_is_rfkill(priv)) {
+		IWL_DEBUG_DROP(priv, "Dropping - RF KILL\n");
+		goto drop_unlock;
+	}
+
+	fc = hdr->frame_control;
+
+#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
+	if (ieee80211_is_auth(fc))
+		IWL_DEBUG_TX(priv, "Sending AUTH frame\n");
+	else if (ieee80211_is_assoc_req(fc))
+		IWL_DEBUG_TX(priv, "Sending ASSOC frame\n");
+	else if (ieee80211_is_reassoc_req(fc))
+		IWL_DEBUG_TX(priv, "Sending REASSOC frame\n");
+#endif
+
+	hdr_len = ieee80211_hdrlen(fc);
+
+	/* Find index into station table for destination station */
+	sta_id = iwl_legacy_sta_id_or_broadcast(priv, ctx, info->control.sta);
+	if (sta_id == IWL_INVALID_STATION) {
+		IWL_DEBUG_DROP(priv, "Dropping - INVALID STATION: %pM\n",
+			       hdr->addr1);
+		goto drop_unlock;
+	}
+
+	IWL_DEBUG_TX(priv, "station Id %d\n", sta_id);
+
+	if (sta)
+		sta_priv = (void *)sta->drv_priv;
+
+	if (sta_priv && sta_priv->asleep &&
+	    (info->flags & IEEE80211_TX_CTL_PSPOLL_RESPONSE)) {
+		/*
+		 * This sends an asynchronous command to the device,
+		 * but we can rely on it being processed before the
+		 * next frame is processed -- and the next frame to
+		 * this station is the one that will consume this
+		 * counter.
+		 * For now set the counter to just 1 since we do not
+		 * support uAPSD yet.
+		 */
+		iwl4965_sta_modify_sleep_tx_count(priv, sta_id, 1);
+	}
+
+	/*
+	 * Send this frame after DTIM -- there's a special queue
+	 * reserved for this for contexts that support AP mode.
+	 */
+	if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
+		txq_id = ctx->mcast_queue;
+		/*
+		 * The microcode will clear the more data
+		 * bit in the last frame it transmits.
+		 */
+		hdr->frame_control |=
+			cpu_to_le16(IEEE80211_FCTL_MOREDATA);
+	} else
+		txq_id = ctx->ac_to_queue[skb_get_queue_mapping(skb)];
+
+	/* irqs already disabled/saved above when locking priv->lock */
+	spin_lock(&priv->sta_lock);
+
+	if (ieee80211_is_data_qos(fc)) {
+		qc = ieee80211_get_qos_ctl(hdr);
+		tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
+		if (WARN_ON_ONCE(tid >= MAX_TID_COUNT)) {
+			spin_unlock(&priv->sta_lock);
+			goto drop_unlock;
+		}
+		seq_number = priv->stations[sta_id].tid[tid].seq_number;
+		seq_number &= IEEE80211_SCTL_SEQ;
+		hdr->seq_ctrl = hdr->seq_ctrl &
+				cpu_to_le16(IEEE80211_SCTL_FRAG);
+		hdr->seq_ctrl |= cpu_to_le16(seq_number);
+		seq_number += 0x10;
+		/* aggregation is on for this <sta,tid> */
+		if (info->flags & IEEE80211_TX_CTL_AMPDU &&
+		    priv->stations[sta_id].tid[tid].agg.state == IWL_AGG_ON) {
+			txq_id = priv->stations[sta_id].tid[tid].agg.txq_id;
+			is_agg = true;
+		}
+	}
+
+	txq = &priv->txq[txq_id];
+	q = &txq->q;
+
+	if (unlikely(iwl_legacy_queue_space(q) < q->high_mark)) {
+		spin_unlock(&priv->sta_lock);
+		goto drop_unlock;
+	}
+
+	if (ieee80211_is_data_qos(fc)) {
+		priv->stations[sta_id].tid[tid].tfds_in_queue++;
+		if (!ieee80211_has_morefrags(fc))
+			priv->stations[sta_id].tid[tid].seq_number = seq_number;
+	}
+
+	spin_unlock(&priv->sta_lock);
+
+	/* Set up driver data for this TFD */
+	memset(&(txq->txb[q->write_ptr]), 0, sizeof(struct iwl_tx_info));
+	txq->txb[q->write_ptr].skb = skb;
+	txq->txb[q->write_ptr].ctx = ctx;
+
+	/* Set up first empty entry in queue's array of Tx/cmd buffers */
+	out_cmd = txq->cmd[q->write_ptr];
+	out_meta = &txq->meta[q->write_ptr];
+	tx_cmd = &out_cmd->cmd.tx;
+	memset(&out_cmd->hdr, 0, sizeof(out_cmd->hdr));
+	memset(tx_cmd, 0, sizeof(struct iwl_tx_cmd));
+
+	/*
+	 * Set up the Tx-command (not MAC!) header.
+	 * Store the chosen Tx queue and TFD index within the sequence field;
+	 * after Tx, uCode's Tx response will return this value so driver can
+	 * locate the frame within the tx queue and do post-tx processing.
+	 */
+	out_cmd->hdr.cmd = REPLY_TX;
+	out_cmd->hdr.sequence = cpu_to_le16((u16)(QUEUE_TO_SEQ(txq_id) |
+				INDEX_TO_SEQ(q->write_ptr)));
+
+	/* Copy MAC header from skb into command buffer */
+	memcpy(tx_cmd->hdr, hdr, hdr_len);
+
+
+	/* Total # bytes to be transmitted */
+	len = (u16)skb->len;
+	tx_cmd->len = cpu_to_le16(len);
+
+	if (info->control.hw_key)
+		iwl4965_tx_cmd_build_hwcrypto(priv, info, tx_cmd, skb, sta_id);
+
+	/* TODO need this for burst mode later on */
+	iwl4965_tx_cmd_build_basic(priv, skb, tx_cmd, info, hdr, sta_id);
+	iwl_legacy_dbg_log_tx_data_frame(priv, len, hdr);
+
+	iwl4965_tx_cmd_build_rate(priv, tx_cmd, info, fc);
+
+	iwl_legacy_update_stats(priv, true, fc, len);
+	/*
+	 * Use the first empty entry in this queue's command buffer array
+	 * to contain the Tx command and MAC header concatenated together
+	 * (payload data will be in another buffer).
+	 * Size of this varies, due to varying MAC header length.
+	 * If end is not dword aligned, we'll have 2 extra bytes at the end
+	 * of the MAC header (device reads on dword boundaries).
+	 * We'll tell device about this padding later.
+	 */
+	len = sizeof(struct iwl_tx_cmd) +
+		sizeof(struct iwl_cmd_header) + hdr_len;
+	firstlen = (len + 3) & ~3;
+
+	/* Tell NIC about any 2-byte padding after MAC header */
+	if (firstlen != len)
+		tx_cmd->tx_flags |= TX_CMD_FLG_MH_PAD_MSK;
+
+	/* Physical address of this Tx command's header (not MAC header!),
+	 * within command buffer array. */
+	txcmd_phys = pci_map_single(priv->pci_dev,
+				    &out_cmd->hdr, firstlen,
+				    PCI_DMA_BIDIRECTIONAL);
+	dma_unmap_addr_set(out_meta, mapping, txcmd_phys);
+	dma_unmap_len_set(out_meta, len, firstlen);
+	/* Add buffer containing Tx command and MAC(!) header to TFD's
+	 * first entry */
+	priv->cfg->ops->lib->txq_attach_buf_to_tfd(priv, txq,
+						   txcmd_phys, firstlen, 1, 0);
+
+	if (!ieee80211_has_morefrags(hdr->frame_control)) {
+		txq->need_update = 1;
+	} else {
+		wait_write_ptr = 1;
+		txq->need_update = 0;
+	}
+
+	/* Set up TFD's 2nd entry to point directly to remainder of skb,
+	 * if any (802.11 null frames have no payload). */
+	secondlen = skb->len - hdr_len;
+	if (secondlen > 0) {
+		phys_addr = pci_map_single(priv->pci_dev, skb->data + hdr_len,
+					   secondlen, PCI_DMA_TODEVICE);
+		priv->cfg->ops->lib->txq_attach_buf_to_tfd(priv, txq,
+							   phys_addr, secondlen,
+							   0, 0);
+	}
+
+	scratch_phys = txcmd_phys + sizeof(struct iwl_cmd_header) +
+				offsetof(struct iwl_tx_cmd, scratch);
+
+	/* take back ownership of DMA buffer to enable update */
+	pci_dma_sync_single_for_cpu(priv->pci_dev, txcmd_phys,
+				    firstlen, PCI_DMA_BIDIRECTIONAL);
+	tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
+	tx_cmd->dram_msb_ptr = iwl_legacy_get_dma_hi_addr(scratch_phys);
+
+	IWL_DEBUG_TX(priv, "sequence nr = 0X%x\n",
+		     le16_to_cpu(out_cmd->hdr.sequence));
+	IWL_DEBUG_TX(priv, "tx_flags = 0X%x\n", le32_to_cpu(tx_cmd->tx_flags));
+	iwl_print_hex_dump(priv, IWL_DL_TX, (u8 *)tx_cmd, sizeof(*tx_cmd));
+	iwl_print_hex_dump(priv, IWL_DL_TX, (u8 *)tx_cmd->hdr, hdr_len);
+
+	/* Set up entry for this TFD in Tx byte-count array */
+	if (info->flags & IEEE80211_TX_CTL_AMPDU)
+		priv->cfg->ops->lib->txq_update_byte_cnt_tbl(priv, txq,
+						     le16_to_cpu(tx_cmd->len));
+
+	pci_dma_sync_single_for_device(priv->pci_dev, txcmd_phys,
+				       firstlen, PCI_DMA_BIDIRECTIONAL);
+
+	trace_iwlwifi_legacy_dev_tx(priv,
+			     &((struct iwl_tfd *)txq->tfds)[txq->q.write_ptr],
+			     sizeof(struct iwl_tfd),
+			     &out_cmd->hdr, firstlen,
+			     skb->data + hdr_len, secondlen);
+
+	/* Tell device the write index *just past* this latest filled TFD */
+	q->write_ptr = iwl_legacy_queue_inc_wrap(q->write_ptr, q->n_bd);
+	iwl_legacy_txq_update_write_ptr(priv, txq);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/*
+	 * At this point the frame is "transmitted" successfully
+	 * and we will get a TX status notification eventually,
+	 * regardless of the value of ret. "ret" only indicates
+	 * whether or not we should update the write pointer.
+	 */
+
+	/*
+	 * Avoid atomic ops if it isn't an associated client.
+	 * Also, if this is a packet for aggregation, don't
+	 * increase the counter because the ucode will stop
+	 * aggregation queues when their respective station
+	 * goes to sleep.
+	 */
+	if (sta_priv && sta_priv->client && !is_agg)
+		atomic_inc(&sta_priv->pending_frames);
+
+	if ((iwl_legacy_queue_space(q) < q->high_mark) &&
+			priv->mac80211_registered) {
+		if (wait_write_ptr) {
+			spin_lock_irqsave(&priv->lock, flags);
+			txq->need_update = 1;
+			iwl_legacy_txq_update_write_ptr(priv, txq);
+			spin_unlock_irqrestore(&priv->lock, flags);
+		} else {
+			iwl_legacy_stop_queue(priv, txq);
+		}
+	}
+
+	return 0;
+
+drop_unlock:
+	spin_unlock_irqrestore(&priv->lock, flags);
+	return -1;
+}
+
+static inline int iwl4965_alloc_dma_ptr(struct iwl_priv *priv,
+				    struct iwl_dma_ptr *ptr, size_t size)
+{
+	ptr->addr = dma_alloc_coherent(&priv->pci_dev->dev, size, &ptr->dma,
+				       GFP_KERNEL);
+	if (!ptr->addr)
+		return -ENOMEM;
+	ptr->size = size;
+	return 0;
+}
+
+static inline void iwl4965_free_dma_ptr(struct iwl_priv *priv,
+				    struct iwl_dma_ptr *ptr)
+{
+	if (unlikely(!ptr->addr))
+		return;
+
+	dma_free_coherent(&priv->pci_dev->dev, ptr->size, ptr->addr, ptr->dma);
+	memset(ptr, 0, sizeof(*ptr));
+}
+
+/**
+ * iwl4965_hw_txq_ctx_free - Free TXQ Context
+ *
+ * Destroy all TX DMA queues and structures
+ */
+void iwl4965_hw_txq_ctx_free(struct iwl_priv *priv)
+{
+	int txq_id;
+
+	/* Tx queues */
+	if (priv->txq) {
+		for (txq_id = 0; txq_id < priv->hw_params.max_txq_num; txq_id++)
+			if (txq_id == priv->cmd_queue)
+				iwl_legacy_cmd_queue_free(priv);
+			else
+				iwl_legacy_tx_queue_free(priv, txq_id);
+	}
+	iwl4965_free_dma_ptr(priv, &priv->kw);
+
+	iwl4965_free_dma_ptr(priv, &priv->scd_bc_tbls);
+
+	/* free tx queue structure */
+	iwl_legacy_txq_mem(priv);
+}
+
+/**
+ * iwl4965_txq_ctx_alloc - allocate TX queue context
+ * Allocate all Tx DMA structures and initialize them
+ *
+ * @param priv
+ * @return error code
+ */
+int iwl4965_txq_ctx_alloc(struct iwl_priv *priv)
+{
+	int ret;
+	int txq_id, slots_num;
+	unsigned long flags;
+
+	/* Free all tx/cmd queues and keep-warm buffer */
+	iwl4965_hw_txq_ctx_free(priv);
+
+	ret = iwl4965_alloc_dma_ptr(priv, &priv->scd_bc_tbls,
+				priv->hw_params.scd_bc_tbls_size);
+	if (ret) {
+		IWL_ERR(priv, "Scheduler BC Table allocation failed\n");
+		goto error_bc_tbls;
+	}
+	/* Alloc keep-warm buffer */
+	ret = iwl4965_alloc_dma_ptr(priv, &priv->kw, IWL_KW_SIZE);
+	if (ret) {
+		IWL_ERR(priv, "Keep Warm allocation failed\n");
+		goto error_kw;
+	}
+
+	/* allocate tx queue structure */
+	ret = iwl_legacy_alloc_txq_mem(priv);
+	if (ret)
+		goto error;
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Turn off all Tx DMA fifos */
+	iwl4965_txq_set_sched(priv, 0);
+
+	/* Tell NIC where to find the "keep warm" buffer */
+	iwl_legacy_write_direct32(priv, FH_KW_MEM_ADDR_REG, priv->kw.dma >> 4);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/* Alloc and init all Tx queues, including the command queue (#4/#9) */
+	for (txq_id = 0; txq_id < priv->hw_params.max_txq_num; txq_id++) {
+		slots_num = (txq_id == priv->cmd_queue) ?
+					TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
+		ret = iwl_legacy_tx_queue_init(priv,
+					&priv->txq[txq_id], slots_num,
+				       txq_id);
+		if (ret) {
+			IWL_ERR(priv, "Tx %d queue init failed\n", txq_id);
+			goto error;
+		}
+	}
+
+	return ret;
+
+ error:
+	iwl4965_hw_txq_ctx_free(priv);
+	iwl4965_free_dma_ptr(priv, &priv->kw);
+ error_kw:
+	iwl4965_free_dma_ptr(priv, &priv->scd_bc_tbls);
+ error_bc_tbls:
+	return ret;
+}
+
+void iwl4965_txq_ctx_reset(struct iwl_priv *priv)
+{
+	int txq_id, slots_num;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Turn off all Tx DMA fifos */
+	iwl4965_txq_set_sched(priv, 0);
+
+	/* Tell NIC where to find the "keep warm" buffer */
+	iwl_legacy_write_direct32(priv, FH_KW_MEM_ADDR_REG, priv->kw.dma >> 4);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/* Alloc and init all Tx queues, including the command queue (#4) */
+	for (txq_id = 0; txq_id < priv->hw_params.max_txq_num; txq_id++) {
+		slots_num = txq_id == priv->cmd_queue ?
+			    TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
+		iwl_legacy_tx_queue_reset(priv, &priv->txq[txq_id],
+						slots_num, txq_id);
+	}
+}
+
+/**
+ * iwl4965_txq_ctx_stop - Stop all Tx DMA channels
+ */
+void iwl4965_txq_ctx_stop(struct iwl_priv *priv)
+{
+	int ch;
+	unsigned long flags;
+
+	/* Turn off all Tx DMA fifos */
+	spin_lock_irqsave(&priv->lock, flags);
+
+	iwl4965_txq_set_sched(priv, 0);
+
+	/* Stop each Tx DMA channel, and wait for it to be idle */
+	for (ch = 0; ch < priv->hw_params.dma_chnl_num; ch++) {
+		iwl_legacy_write_direct32(priv,
+				FH_TCSR_CHNL_TX_CONFIG_REG(ch), 0x0);
+		if (iwl_poll_direct_bit(priv, FH_TSSR_TX_STATUS_REG,
+				    FH_TSSR_TX_STATUS_REG_MSK_CHNL_IDLE(ch),
+				    1000))
+			IWL_ERR(priv, "Failing on timeout while stopping"
+			    " DMA channel %d [0x%08x]", ch,
+			    iwl_legacy_read_direct32(priv,
+					FH_TSSR_TX_STATUS_REG));
+	}
+	spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+/*
+ * Find first available (lowest unused) Tx Queue, mark it "active".
+ * Called only when finding queue for aggregation.
+ * Should never return anything < 7, because they should already
+ * be in use as EDCA AC (0-3), Command (4), reserved (5, 6)
+ */
+static int iwl4965_txq_ctx_activate_free(struct iwl_priv *priv)
+{
+	int txq_id;
+
+	for (txq_id = 0; txq_id < priv->hw_params.max_txq_num; txq_id++)
+		if (!test_and_set_bit(txq_id, &priv->txq_ctx_active_msk))
+			return txq_id;
+	return -1;
+}
+
+/**
+ * iwl4965_tx_queue_stop_scheduler - Stop queue, but keep configuration
+ */
+static void iwl4965_tx_queue_stop_scheduler(struct iwl_priv *priv,
+					    u16 txq_id)
+{
+	/* Simply stop the queue, but don't change any configuration;
+	 * the SCD_ACT_EN bit is the write-enable mask for the ACTIVE bit. */
+	iwl_legacy_write_prph(priv,
+		IWL49_SCD_QUEUE_STATUS_BITS(txq_id),
+		(0 << IWL49_SCD_QUEUE_STTS_REG_POS_ACTIVE)|
+		(1 << IWL49_SCD_QUEUE_STTS_REG_POS_SCD_ACT_EN));
+}
+
+/**
+ * iwl4965_tx_queue_set_q2ratid - Map unique receiver/tid combination to a queue
+ */
+static int iwl4965_tx_queue_set_q2ratid(struct iwl_priv *priv, u16 ra_tid,
+					u16 txq_id)
+{
+	u32 tbl_dw_addr;
+	u32 tbl_dw;
+	u16 scd_q2ratid;
+
+	scd_q2ratid = ra_tid & IWL_SCD_QUEUE_RA_TID_MAP_RATID_MSK;
+
+	tbl_dw_addr = priv->scd_base_addr +
+			IWL49_SCD_TRANSLATE_TBL_OFFSET_QUEUE(txq_id);
+
+	tbl_dw = iwl_legacy_read_targ_mem(priv, tbl_dw_addr);
+
+	if (txq_id & 0x1)
+		tbl_dw = (scd_q2ratid << 16) | (tbl_dw & 0x0000FFFF);
+	else
+		tbl_dw = scd_q2ratid | (tbl_dw & 0xFFFF0000);
+
+	iwl_legacy_write_targ_mem(priv, tbl_dw_addr, tbl_dw);
+
+	return 0;
+}
+
+/**
+ * iwl4965_tx_queue_agg_enable - Set up & enable aggregation for selected queue
+ *
+ * NOTE:  txq_id must be greater than IWL49_FIRST_AMPDU_QUEUE,
+ *        i.e. it must be one of the higher queues used for aggregation
+ */
+static int iwl4965_txq_agg_enable(struct iwl_priv *priv, int txq_id,
+				  int tx_fifo, int sta_id, int tid, u16 ssn_idx)
+{
+	unsigned long flags;
+	u16 ra_tid;
+	int ret;
+
+	if ((IWL49_FIRST_AMPDU_QUEUE > txq_id) ||
+	    (IWL49_FIRST_AMPDU_QUEUE +
+		priv->cfg->base_params->num_of_ampdu_queues <= txq_id)) {
+		IWL_WARN(priv,
+			"queue number out of range: %d, must be %d to %d\n",
+			txq_id, IWL49_FIRST_AMPDU_QUEUE,
+			IWL49_FIRST_AMPDU_QUEUE +
+			priv->cfg->base_params->num_of_ampdu_queues - 1);
+		return -EINVAL;
+	}
+
+	ra_tid = BUILD_RAxTID(sta_id, tid);
+
+	/* Modify device's station table to Tx this TID */
+	ret = iwl4965_sta_tx_modify_enable_tid(priv, sta_id, tid);
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Stop this Tx queue before configuring it */
+	iwl4965_tx_queue_stop_scheduler(priv, txq_id);
+
+	/* Map receiver-address / traffic-ID to this queue */
+	iwl4965_tx_queue_set_q2ratid(priv, ra_tid, txq_id);
+
+	/* Set this queue as a chain-building queue */
+	iwl_legacy_set_bits_prph(priv, IWL49_SCD_QUEUECHAIN_SEL, (1 << txq_id));
+
+	/* Place first TFD at index corresponding to start sequence number.
+	 * Assumes that ssn_idx is valid (!= 0xFFF) */
+	priv->txq[txq_id].q.read_ptr = (ssn_idx & 0xff);
+	priv->txq[txq_id].q.write_ptr = (ssn_idx & 0xff);
+	iwl4965_set_wr_ptrs(priv, txq_id, ssn_idx);
+
+	/* Set up Tx window size and frame limit for this queue */
+	iwl_legacy_write_targ_mem(priv,
+		priv->scd_base_addr + IWL49_SCD_CONTEXT_QUEUE_OFFSET(txq_id),
+		(SCD_WIN_SIZE << IWL49_SCD_QUEUE_CTX_REG1_WIN_SIZE_POS) &
+		IWL49_SCD_QUEUE_CTX_REG1_WIN_SIZE_MSK);
+
+	iwl_legacy_write_targ_mem(priv, priv->scd_base_addr +
+		IWL49_SCD_CONTEXT_QUEUE_OFFSET(txq_id) + sizeof(u32),
+		(SCD_FRAME_LIMIT << IWL49_SCD_QUEUE_CTX_REG2_FRAME_LIMIT_POS)
+		& IWL49_SCD_QUEUE_CTX_REG2_FRAME_LIMIT_MSK);
+
+	iwl_legacy_set_bits_prph(priv, IWL49_SCD_INTERRUPT_MASK, (1 << txq_id));
+
+	/* Set up Status area in SRAM, map to Tx DMA/FIFO, activate the queue */
+	iwl4965_tx_queue_set_status(priv, &priv->txq[txq_id], tx_fifo, 1);
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return 0;
+}
+
+
+int iwl4965_tx_agg_start(struct iwl_priv *priv, struct ieee80211_vif *vif,
+			struct ieee80211_sta *sta, u16 tid, u16 *ssn)
+{
+	int sta_id;
+	int tx_fifo;
+	int txq_id;
+	int ret;
+	unsigned long flags;
+	struct iwl_tid_data *tid_data;
+
+	tx_fifo = iwl4965_get_fifo_from_tid(iwl_legacy_rxon_ctx_from_vif(vif), tid);
+	if (unlikely(tx_fifo < 0))
+		return tx_fifo;
+
+	IWL_WARN(priv, "%s on ra = %pM tid = %d\n",
+			__func__, sta->addr, tid);
+
+	sta_id = iwl_legacy_sta_id(sta);
+	if (sta_id == IWL_INVALID_STATION) {
+		IWL_ERR(priv, "Start AGG on invalid station\n");
+		return -ENXIO;
+	}
+	if (unlikely(tid >= MAX_TID_COUNT))
+		return -EINVAL;
+
+	if (priv->stations[sta_id].tid[tid].agg.state != IWL_AGG_OFF) {
+		IWL_ERR(priv, "Start AGG when state is not IWL_AGG_OFF !\n");
+		return -ENXIO;
+	}
+
+	txq_id = iwl4965_txq_ctx_activate_free(priv);
+	if (txq_id == -1) {
+		IWL_ERR(priv, "No free aggregation queue available\n");
+		return -ENXIO;
+	}
+
+	spin_lock_irqsave(&priv->sta_lock, flags);
+	tid_data = &priv->stations[sta_id].tid[tid];
+	*ssn = SEQ_TO_SN(tid_data->seq_number);
+	tid_data->agg.txq_id = txq_id;
+	iwl_legacy_set_swq_id(&priv->txq[txq_id],
+				iwl4965_get_ac_from_tid(tid), txq_id);
+	spin_unlock_irqrestore(&priv->sta_lock, flags);
+
+	ret = iwl4965_txq_agg_enable(priv, txq_id, tx_fifo,
+						  sta_id, tid, *ssn);
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&priv->sta_lock, flags);
+	tid_data = &priv->stations[sta_id].tid[tid];
+	if (tid_data->tfds_in_queue == 0) {
+		IWL_DEBUG_HT(priv, "HW queue is empty\n");
+		tid_data->agg.state = IWL_AGG_ON;
+		ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
+	} else {
+		IWL_DEBUG_HT(priv,
+			"HW queue is NOT empty: %d packets in HW queue\n",
+			     tid_data->tfds_in_queue);
+		tid_data->agg.state = IWL_EMPTYING_HW_QUEUE_ADDBA;
+	}
+	spin_unlock_irqrestore(&priv->sta_lock, flags);
+	return ret;
+}
+
+/**
+ * txq_id must be greater than IWL49_FIRST_AMPDU_QUEUE
+ * priv->lock must be held by the caller
+ */
+static int iwl4965_txq_agg_disable(struct iwl_priv *priv, u16 txq_id,
+				   u16 ssn_idx, u8 tx_fifo)
+{
+	if ((IWL49_FIRST_AMPDU_QUEUE > txq_id) ||
+	    (IWL49_FIRST_AMPDU_QUEUE +
+		priv->cfg->base_params->num_of_ampdu_queues <= txq_id)) {
+		IWL_WARN(priv,
+			"queue number out of range: %d, must be %d to %d\n",
+			txq_id, IWL49_FIRST_AMPDU_QUEUE,
+			IWL49_FIRST_AMPDU_QUEUE +
+			priv->cfg->base_params->num_of_ampdu_queues - 1);
+		return -EINVAL;
+	}
+
+	iwl4965_tx_queue_stop_scheduler(priv, txq_id);
+
+	iwl_legacy_clear_bits_prph(priv,
+			IWL49_SCD_QUEUECHAIN_SEL, (1 << txq_id));
+
+	priv->txq[txq_id].q.read_ptr = (ssn_idx & 0xff);
+	priv->txq[txq_id].q.write_ptr = (ssn_idx & 0xff);
+	/* supposes that ssn_idx is valid (!= 0xFFF) */
+	iwl4965_set_wr_ptrs(priv, txq_id, ssn_idx);
+
+	iwl_legacy_clear_bits_prph(priv,
+			 IWL49_SCD_INTERRUPT_MASK, (1 << txq_id));
+	iwl_txq_ctx_deactivate(priv, txq_id);
+	iwl4965_tx_queue_set_status(priv, &priv->txq[txq_id], tx_fifo, 0);
+
+	return 0;
+}
+
+int iwl4965_tx_agg_stop(struct iwl_priv *priv, struct ieee80211_vif *vif,
+		       struct ieee80211_sta *sta, u16 tid)
+{
+	int tx_fifo_id, txq_id, sta_id, ssn;
+	struct iwl_tid_data *tid_data;
+	int write_ptr, read_ptr;
+	unsigned long flags;
+
+	tx_fifo_id = iwl4965_get_fifo_from_tid(iwl_legacy_rxon_ctx_from_vif(vif), tid);
+	if (unlikely(tx_fifo_id < 0))
+		return tx_fifo_id;
+
+	sta_id = iwl_legacy_sta_id(sta);
+
+	if (sta_id == IWL_INVALID_STATION) {
+		IWL_ERR(priv, "Invalid station for AGG tid %d\n", tid);
+		return -ENXIO;
+	}
+
+	spin_lock_irqsave(&priv->sta_lock, flags);
+
+	tid_data = &priv->stations[sta_id].tid[tid];
+	ssn = (tid_data->seq_number & IEEE80211_SCTL_SEQ) >> 4;
+	txq_id = tid_data->agg.txq_id;
+
+	switch (priv->stations[sta_id].tid[tid].agg.state) {
+	case IWL_EMPTYING_HW_QUEUE_ADDBA:
+		/*
+		 * This can happen if the peer stops aggregation
+		 * again before we've had a chance to drain the
+		 * queue we selected previously, i.e. before the
+		 * session was really started completely.
+		 */
+		IWL_DEBUG_HT(priv, "AGG stop before setup done\n");
+		goto turn_off;
+	case IWL_AGG_ON:
+		break;
+	default:
+		IWL_WARN(priv, "Stopping AGG while state not ON or starting\n");
+	}
+
+	write_ptr = priv->txq[txq_id].q.write_ptr;
+	read_ptr = priv->txq[txq_id].q.read_ptr;
+
+	/* The queue is not empty */
+	if (write_ptr != read_ptr) {
+		IWL_DEBUG_HT(priv, "Stopping a non empty AGG HW QUEUE\n");
+		priv->stations[sta_id].tid[tid].agg.state =
+				IWL_EMPTYING_HW_QUEUE_DELBA;
+		spin_unlock_irqrestore(&priv->sta_lock, flags);
+		return 0;
+	}
+
+	IWL_DEBUG_HT(priv, "HW queue is empty\n");
+ turn_off:
+	priv->stations[sta_id].tid[tid].agg.state = IWL_AGG_OFF;
+
+	/* do not restore/save irqs */
+	spin_unlock(&priv->sta_lock);
+	spin_lock(&priv->lock);
+
+	/*
+	 * the only reason this call can fail is queue number out of range,
+	 * which can happen if uCode is reloaded and all the station
+	 * information are lost. if it is outside the range, there is no need
+	 * to deactivate the uCode queue, just return "success" to allow
+	 *  mac80211 to clean up it own data.
+	 */
+	iwl4965_txq_agg_disable(priv, txq_id, ssn, tx_fifo_id);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
+
+	return 0;
+}
+
+int iwl4965_txq_check_empty(struct iwl_priv *priv,
+			   int sta_id, u8 tid, int txq_id)
+{
+	struct iwl_queue *q = &priv->txq[txq_id].q;
+	u8 *addr = priv->stations[sta_id].sta.sta.addr;
+	struct iwl_tid_data *tid_data = &priv->stations[sta_id].tid[tid];
+	struct iwl_rxon_context *ctx;
+
+	ctx = &priv->contexts[priv->stations[sta_id].ctxid];
+
+	lockdep_assert_held(&priv->sta_lock);
+
+	switch (priv->stations[sta_id].tid[tid].agg.state) {
+	case IWL_EMPTYING_HW_QUEUE_DELBA:
+		/* We are reclaiming the last packet of the */
+		/* aggregated HW queue */
+		if ((txq_id  == tid_data->agg.txq_id) &&
+		    (q->read_ptr == q->write_ptr)) {
+			u16 ssn = SEQ_TO_SN(tid_data->seq_number);
+			int tx_fifo = iwl4965_get_fifo_from_tid(ctx, tid);
+			IWL_DEBUG_HT(priv,
+				"HW queue empty: continue DELBA flow\n");
+			iwl4965_txq_agg_disable(priv, txq_id, ssn, tx_fifo);
+			tid_data->agg.state = IWL_AGG_OFF;
+			ieee80211_stop_tx_ba_cb_irqsafe(ctx->vif, addr, tid);
+		}
+		break;
+	case IWL_EMPTYING_HW_QUEUE_ADDBA:
+		/* We are reclaiming the last packet of the queue */
+		if (tid_data->tfds_in_queue == 0) {
+			IWL_DEBUG_HT(priv,
+				"HW queue empty: continue ADDBA flow\n");
+			tid_data->agg.state = IWL_AGG_ON;
+			ieee80211_start_tx_ba_cb_irqsafe(ctx->vif, addr, tid);
+		}
+		break;
+	}
+
+	return 0;
+}
+
+static void iwl4965_non_agg_tx_status(struct iwl_priv *priv,
+				     struct iwl_rxon_context *ctx,
+				     const u8 *addr1)
+{
+	struct ieee80211_sta *sta;
+	struct iwl_station_priv *sta_priv;
+
+	rcu_read_lock();
+	sta = ieee80211_find_sta(ctx->vif, addr1);
+	if (sta) {
+		sta_priv = (void *)sta->drv_priv;
+		/* avoid atomic ops if this isn't a client */
+		if (sta_priv->client &&
+		    atomic_dec_return(&sta_priv->pending_frames) == 0)
+			ieee80211_sta_block_awake(priv->hw, sta, false);
+	}
+	rcu_read_unlock();
+}
+
+static void
+iwl4965_tx_status(struct iwl_priv *priv, struct iwl_tx_info *tx_info,
+			     bool is_agg)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx_info->skb->data;
+
+	if (!is_agg)
+		iwl4965_non_agg_tx_status(priv, tx_info->ctx, hdr->addr1);
+
+	ieee80211_tx_status_irqsafe(priv->hw, tx_info->skb);
+}
+
+int iwl4965_tx_queue_reclaim(struct iwl_priv *priv, int txq_id, int index)
+{
+	struct iwl_tx_queue *txq = &priv->txq[txq_id];
+	struct iwl_queue *q = &txq->q;
+	struct iwl_tx_info *tx_info;
+	int nfreed = 0;
+	struct ieee80211_hdr *hdr;
+
+	if ((index >= q->n_bd) || (iwl_legacy_queue_used(q, index) == 0)) {
+		IWL_ERR(priv, "Read index for DMA queue txq id (%d), index %d, "
+			  "is out of range [0-%d] %d %d.\n", txq_id,
+			  index, q->n_bd, q->write_ptr, q->read_ptr);
+		return 0;
+	}
+
+	for (index = iwl_legacy_queue_inc_wrap(index, q->n_bd);
+	     q->read_ptr != index;
+	     q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd)) {
+
+		tx_info = &txq->txb[txq->q.read_ptr];
+		iwl4965_tx_status(priv, tx_info,
+				 txq_id >= IWL4965_FIRST_AMPDU_QUEUE);
+
+		hdr = (struct ieee80211_hdr *)tx_info->skb->data;
+		if (hdr && ieee80211_is_data_qos(hdr->frame_control))
+			nfreed++;
+		tx_info->skb = NULL;
+
+		priv->cfg->ops->lib->txq_free_tfd(priv, txq);
+	}
+	return nfreed;
+}
+
+/**
+ * iwl4965_tx_status_reply_compressed_ba - Update tx status from block-ack
+ *
+ * Go through block-ack's bitmap of ACK'd frames, update driver's record of
+ * ACK vs. not.  This gets sent to mac80211, then to rate scaling algo.
+ */
+static int iwl4965_tx_status_reply_compressed_ba(struct iwl_priv *priv,
+				 struct iwl_ht_agg *agg,
+				 struct iwl_compressed_ba_resp *ba_resp)
+
+{
+	int i, sh, ack;
+	u16 seq_ctl = le16_to_cpu(ba_resp->seq_ctl);
+	u16 scd_flow = le16_to_cpu(ba_resp->scd_flow);
+	int successes = 0;
+	struct ieee80211_tx_info *info;
+	u64 bitmap, sent_bitmap;
+
+	if (unlikely(!agg->wait_for_ba))  {
+		if (unlikely(ba_resp->bitmap))
+			IWL_ERR(priv, "Received BA when not expected\n");
+		return -EINVAL;
+	}
+
+	/* Mark that the expected block-ack response arrived */
+	agg->wait_for_ba = 0;
+	IWL_DEBUG_TX_REPLY(priv, "BA %d %d\n", agg->start_idx,
+							ba_resp->seq_ctl);
+
+	/* Calculate shift to align block-ack bits with our Tx window bits */
+	sh = agg->start_idx - SEQ_TO_INDEX(seq_ctl >> 4);
+	if (sh < 0) /* tbw something is wrong with indices */
+		sh += 0x100;
+
+	if (agg->frame_count > (64 - sh)) {
+		IWL_DEBUG_TX_REPLY(priv, "more frames than bitmap size");
+		return -1;
+	}
+
+	/* don't use 64-bit values for now */
+	bitmap = le64_to_cpu(ba_resp->bitmap) >> sh;
+
+	/* check for success or failure according to the
+	 * transmitted bitmap and block-ack bitmap */
+	sent_bitmap = bitmap & agg->bitmap;
+
+	/* For each frame attempted in aggregation,
+	 * update driver's record of tx frame's status. */
+	i = 0;
+	while (sent_bitmap) {
+		ack = sent_bitmap & 1ULL;
+		successes += ack;
+		IWL_DEBUG_TX_REPLY(priv, "%s ON i=%d idx=%d raw=%d\n",
+			ack ? "ACK" : "NACK", i,
+			(agg->start_idx + i) & 0xff,
+			agg->start_idx + i);
+		sent_bitmap >>= 1;
+		++i;
+	}
+
+	IWL_DEBUG_TX_REPLY(priv, "Bitmap %llx\n",
+				   (unsigned long long)bitmap);
+
+	info = IEEE80211_SKB_CB(priv->txq[scd_flow].txb[agg->start_idx].skb);
+	memset(&info->status, 0, sizeof(info->status));
+	info->flags |= IEEE80211_TX_STAT_ACK;
+	info->flags |= IEEE80211_TX_STAT_AMPDU;
+	info->status.ampdu_ack_len = successes;
+	info->status.ampdu_len = agg->frame_count;
+	iwl4965_hwrate_to_tx_control(priv, agg->rate_n_flags, info);
+
+	return 0;
+}
+
+/**
+ * translate ucode response to mac80211 tx status control values
+ */
+void iwl4965_hwrate_to_tx_control(struct iwl_priv *priv, u32 rate_n_flags,
+				  struct ieee80211_tx_info *info)
+{
+	struct ieee80211_tx_rate *r = &info->control.rates[0];
+
+	info->antenna_sel_tx =
+		((rate_n_flags & RATE_MCS_ANT_ABC_MSK) >> RATE_MCS_ANT_POS);
+	if (rate_n_flags & RATE_MCS_HT_MSK)
+		r->flags |= IEEE80211_TX_RC_MCS;
+	if (rate_n_flags & RATE_MCS_GF_MSK)
+		r->flags |= IEEE80211_TX_RC_GREEN_FIELD;
+	if (rate_n_flags & RATE_MCS_HT40_MSK)
+		r->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
+	if (rate_n_flags & RATE_MCS_DUP_MSK)
+		r->flags |= IEEE80211_TX_RC_DUP_DATA;
+	if (rate_n_flags & RATE_MCS_SGI_MSK)
+		r->flags |= IEEE80211_TX_RC_SHORT_GI;
+	r->idx = iwl4965_hwrate_to_mac80211_idx(rate_n_flags, info->band);
+}
+
+/**
+ * iwl4965_rx_reply_compressed_ba - Handler for REPLY_COMPRESSED_BA
+ *
+ * Handles block-acknowledge notification from device, which reports success
+ * of frames sent via aggregation.
+ */
+void iwl4965_rx_reply_compressed_ba(struct iwl_priv *priv,
+					   struct iwl_rx_mem_buffer *rxb)
+{
+	struct iwl_rx_packet *pkt = rxb_addr(rxb);
+	struct iwl_compressed_ba_resp *ba_resp = &pkt->u.compressed_ba;
+	struct iwl_tx_queue *txq = NULL;
+	struct iwl_ht_agg *agg;
+	int index;
+	int sta_id;
+	int tid;
+	unsigned long flags;
+
+	/* "flow" corresponds to Tx queue */
+	u16 scd_flow = le16_to_cpu(ba_resp->scd_flow);
+
+	/* "ssn" is start of block-ack Tx window, corresponds to index
+	 * (in Tx queue's circular buffer) of first TFD/frame in window */
+	u16 ba_resp_scd_ssn = le16_to_cpu(ba_resp->scd_ssn);
+
+	if (scd_flow >= priv->hw_params.max_txq_num) {
+		IWL_ERR(priv,
+			"BUG_ON scd_flow is bigger than number of queues\n");
+		return;
+	}
+
+	txq = &priv->txq[scd_flow];
+	sta_id = ba_resp->sta_id;
+	tid = ba_resp->tid;
+	agg = &priv->stations[sta_id].tid[tid].agg;
+	if (unlikely(agg->txq_id != scd_flow)) {
+		/*
+		 * FIXME: this is a uCode bug which need to be addressed,
+		 * log the information and return for now!
+		 * since it is possible happen very often and in order
+		 * not to fill the syslog, don't enable the logging by default
+		 */
+		IWL_DEBUG_TX_REPLY(priv,
+			"BA scd_flow %d does not match txq_id %d\n",
+			scd_flow, agg->txq_id);
+		return;
+	}
+
+	/* Find index just before block-ack window */
+	index = iwl_legacy_queue_dec_wrap(ba_resp_scd_ssn & 0xff, txq->q.n_bd);
+
+	spin_lock_irqsave(&priv->sta_lock, flags);
+
+	IWL_DEBUG_TX_REPLY(priv, "REPLY_COMPRESSED_BA [%d] Received from %pM, "
+			   "sta_id = %d\n",
+			   agg->wait_for_ba,
+			   (u8 *) &ba_resp->sta_addr_lo32,
+			   ba_resp->sta_id);
+	IWL_DEBUG_TX_REPLY(priv, "TID = %d, SeqCtl = %d, bitmap = 0x%llx,"
+			"scd_flow = "
+			   "%d, scd_ssn = %d\n",
+			   ba_resp->tid,
+			   ba_resp->seq_ctl,
+			   (unsigned long long)le64_to_cpu(ba_resp->bitmap),
+			   ba_resp->scd_flow,
+			   ba_resp->scd_ssn);
+	IWL_DEBUG_TX_REPLY(priv, "DAT start_idx = %d, bitmap = 0x%llx\n",
+			   agg->start_idx,
+			   (unsigned long long)agg->bitmap);
+
+	/* Update driver's record of ACK vs. not for each frame in window */
+	iwl4965_tx_status_reply_compressed_ba(priv, agg, ba_resp);
+
+	/* Release all TFDs before the SSN, i.e. all TFDs in front of
+	 * block-ack window (we assume that they've been successfully
+	 * transmitted ... if not, it's too late anyway). */
+	if (txq->q.read_ptr != (ba_resp_scd_ssn & 0xff)) {
+		/* calculate mac80211 ampdu sw queue to wake */
+		int freed = iwl4965_tx_queue_reclaim(priv, scd_flow, index);
+		iwl4965_free_tfds_in_queue(priv, sta_id, tid, freed);
+
+		if ((iwl_legacy_queue_space(&txq->q) > txq->q.low_mark) &&
+		    priv->mac80211_registered &&
+		    (agg->state != IWL_EMPTYING_HW_QUEUE_DELBA))
+			iwl_legacy_wake_queue(priv, txq);
+
+		iwl4965_txq_check_empty(priv, sta_id, tid, scd_flow);
+	}
+
+	spin_unlock_irqrestore(&priv->sta_lock, flags);
+}
+
+#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
+const char *iwl4965_get_tx_fail_reason(u32 status)
+{
+#define TX_STATUS_FAIL(x) case TX_STATUS_FAIL_ ## x: return #x
+#define TX_STATUS_POSTPONE(x) case TX_STATUS_POSTPONE_ ## x: return #x
+
+	switch (status & TX_STATUS_MSK) {
+	case TX_STATUS_SUCCESS:
+		return "SUCCESS";
+	TX_STATUS_POSTPONE(DELAY);
+	TX_STATUS_POSTPONE(FEW_BYTES);
+	TX_STATUS_POSTPONE(QUIET_PERIOD);
+	TX_STATUS_POSTPONE(CALC_TTAK);
+	TX_STATUS_FAIL(INTERNAL_CROSSED_RETRY);
+	TX_STATUS_FAIL(SHORT_LIMIT);
+	TX_STATUS_FAIL(LONG_LIMIT);
+	TX_STATUS_FAIL(FIFO_UNDERRUN);
+	TX_STATUS_FAIL(DRAIN_FLOW);
+	TX_STATUS_FAIL(RFKILL_FLUSH);
+	TX_STATUS_FAIL(LIFE_EXPIRE);
+	TX_STATUS_FAIL(DEST_PS);
+	TX_STATUS_FAIL(HOST_ABORTED);
+	TX_STATUS_FAIL(BT_RETRY);
+	TX_STATUS_FAIL(STA_INVALID);
+	TX_STATUS_FAIL(FRAG_DROPPED);
+	TX_STATUS_FAIL(TID_DISABLE);
+	TX_STATUS_FAIL(FIFO_FLUSHED);
+	TX_STATUS_FAIL(INSUFFICIENT_CF_POLL);
+	TX_STATUS_FAIL(PASSIVE_NO_RX);
+	TX_STATUS_FAIL(NO_BEACON_ON_RADAR);
+	}
+
+	return "UNKNOWN";
+
+#undef TX_STATUS_FAIL
+#undef TX_STATUS_POSTPONE
+}
+#endif /* CONFIG_IWLWIFI_LEGACY_DEBUG */