summary refs log tree commit diff
path: root/drivers/net/wireless/iwlwifi/iwl-tx.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-tx.c')
-rw-r--r--drivers/net/wireless/iwlwifi/iwl-tx.c1519
1 files changed, 1519 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c
new file mode 100644
index 000000000000..9b50b1052b09
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-tx.c
@@ -0,0 +1,1519 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2003 - 2008 Intel Corporation. All rights reserved.
+ *
+ * Portions of this file are derived from the ipw3945 project, as well
+ * as portions of the ieee80211 subsystem header files.
+ *
+ * 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.
+ *
+ * Contact Information:
+ * James P. Ketrenos <ipw2100-admin@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+
+#include <linux/etherdevice.h>
+#include <net/mac80211.h>
+#include "iwl-eeprom.h"
+#include "iwl-dev.h"
+#include "iwl-core.h"
+#include "iwl-sta.h"
+#include "iwl-io.h"
+#include "iwl-helpers.h"
+
+static const u16 default_tid_to_tx_fifo[] = {
+	IWL_TX_FIFO_AC1,
+	IWL_TX_FIFO_AC0,
+	IWL_TX_FIFO_AC0,
+	IWL_TX_FIFO_AC1,
+	IWL_TX_FIFO_AC2,
+	IWL_TX_FIFO_AC2,
+	IWL_TX_FIFO_AC3,
+	IWL_TX_FIFO_AC3,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_NONE,
+	IWL_TX_FIFO_AC3
+};
+
+
+/**
+ * iwl_hw_txq_free_tfd - Free all chunks referenced by TFD [txq->q.read_ptr]
+ *
+ * Does NOT advance any TFD circular buffer read/write indexes
+ * Does NOT free the TFD itself (which is within circular buffer)
+ */
+int iwl_hw_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
+{
+	struct iwl_tfd_frame *bd_tmp = (struct iwl_tfd_frame *)&txq->bd[0];
+	struct iwl_tfd_frame *bd = &bd_tmp[txq->q.read_ptr];
+	struct pci_dev *dev = priv->pci_dev;
+	int i;
+	int counter = 0;
+	int index, is_odd;
+
+	/* Host command buffers stay mapped in memory, nothing to clean */
+	if (txq->q.id == IWL_CMD_QUEUE_NUM)
+		return 0;
+
+	/* Sanity check on number of chunks */
+	counter = IWL_GET_BITS(*bd, num_tbs);
+	if (counter > MAX_NUM_OF_TBS) {
+		IWL_ERROR("Too many chunks: %i\n", counter);
+		/* @todo issue fatal error, it is quite serious situation */
+		return 0;
+	}
+
+	/* Unmap chunks, if any.
+	 * TFD info for odd chunks is different format than for even chunks. */
+	for (i = 0; i < counter; i++) {
+		index = i / 2;
+		is_odd = i & 0x1;
+
+		if (is_odd)
+			pci_unmap_single(
+				dev,
+				IWL_GET_BITS(bd->pa[index], tb2_addr_lo16) |
+				(IWL_GET_BITS(bd->pa[index],
+					      tb2_addr_hi20) << 16),
+				IWL_GET_BITS(bd->pa[index], tb2_len),
+				PCI_DMA_TODEVICE);
+
+		else if (i > 0)
+			pci_unmap_single(dev,
+					 le32_to_cpu(bd->pa[index].tb1_addr),
+					 IWL_GET_BITS(bd->pa[index], tb1_len),
+					 PCI_DMA_TODEVICE);
+
+		/* Free SKB, if any, for this chunk */
+		if (txq->txb[txq->q.read_ptr].skb[i]) {
+			struct sk_buff *skb = txq->txb[txq->q.read_ptr].skb[i];
+
+			dev_kfree_skb(skb);
+			txq->txb[txq->q.read_ptr].skb[i] = NULL;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL(iwl_hw_txq_free_tfd);
+
+
+int iwl_hw_txq_attach_buf_to_tfd(struct iwl_priv *priv, void *ptr,
+				 dma_addr_t addr, u16 len)
+{
+	int index, is_odd;
+	struct iwl_tfd_frame *tfd = ptr;
+	u32 num_tbs = IWL_GET_BITS(*tfd, num_tbs);
+
+	/* Each TFD can point to a maximum 20 Tx buffers */
+	if ((num_tbs >= MAX_NUM_OF_TBS) || (num_tbs < 0)) {
+		IWL_ERROR("Error can not send more than %d chunks\n",
+			  MAX_NUM_OF_TBS);
+		return -EINVAL;
+	}
+
+	index = num_tbs / 2;
+	is_odd = num_tbs & 0x1;
+
+	if (!is_odd) {
+		tfd->pa[index].tb1_addr = cpu_to_le32(addr);
+		IWL_SET_BITS(tfd->pa[index], tb1_addr_hi,
+			     iwl_get_dma_hi_address(addr));
+		IWL_SET_BITS(tfd->pa[index], tb1_len, len);
+	} else {
+		IWL_SET_BITS(tfd->pa[index], tb2_addr_lo16,
+			     (u32) (addr & 0xffff));
+		IWL_SET_BITS(tfd->pa[index], tb2_addr_hi20, addr >> 16);
+		IWL_SET_BITS(tfd->pa[index], tb2_len, len);
+	}
+
+	IWL_SET_BITS(*tfd, num_tbs, num_tbs + 1);
+
+	return 0;
+}
+EXPORT_SYMBOL(iwl_hw_txq_attach_buf_to_tfd);
+
+/**
+ * iwl_txq_update_write_ptr - Send new write index to hardware
+ */
+int iwl_txq_update_write_ptr(struct iwl_priv *priv, struct iwl_tx_queue *txq)
+{
+	u32 reg = 0;
+	int ret = 0;
+	int txq_id = txq->q.id;
+
+	if (txq->need_update == 0)
+		return ret;
+
+	/* if we're trying to save power */
+	if (test_bit(STATUS_POWER_PMI, &priv->status)) {
+		/* wake up nic if it's powered down ...
+		 * uCode will wake up, and interrupt us again, so next
+		 * time we'll skip this part. */
+		reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
+
+		if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
+			IWL_DEBUG_INFO("Requesting wakeup, GP1 = 0x%x\n", reg);
+			iwl_set_bit(priv, CSR_GP_CNTRL,
+				    CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+			return ret;
+		}
+
+		/* restore this queue's parameters in nic hardware. */
+		ret = iwl_grab_nic_access(priv);
+		if (ret)
+			return ret;
+		iwl_write_direct32(priv, HBUS_TARG_WRPTR,
+				     txq->q.write_ptr | (txq_id << 8));
+		iwl_release_nic_access(priv);
+
+	/* else not in power-save mode, uCode will never sleep when we're
+	 * trying to tx (during RFKILL, we're not trying to tx). */
+	} else
+		iwl_write32(priv, HBUS_TARG_WRPTR,
+			    txq->q.write_ptr | (txq_id << 8));
+
+	txq->need_update = 0;
+
+	return ret;
+}
+EXPORT_SYMBOL(iwl_txq_update_write_ptr);
+
+
+/**
+ * iwl_tx_queue_free - Deallocate DMA queue.
+ * @txq: Transmit queue to deallocate.
+ *
+ * Empty queue by removing and destroying all BD's.
+ * Free all buffers.
+ * 0-fill, but do not free "txq" descriptor structure.
+ */
+static void iwl_tx_queue_free(struct iwl_priv *priv, struct iwl_tx_queue *txq)
+{
+	struct iwl_queue *q = &txq->q;
+	struct pci_dev *dev = priv->pci_dev;
+	int len;
+
+	if (q->n_bd == 0)
+		return;
+
+	/* first, empty all BD's */
+	for (; q->write_ptr != q->read_ptr;
+	     q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd))
+		iwl_hw_txq_free_tfd(priv, txq);
+
+	len = sizeof(struct iwl_cmd) * q->n_window;
+	if (q->id == IWL_CMD_QUEUE_NUM)
+		len += IWL_MAX_SCAN_SIZE;
+
+	/* De-alloc array of command/tx buffers */
+	pci_free_consistent(dev, len, txq->cmd, txq->dma_addr_cmd);
+
+	/* De-alloc circular buffer of TFDs */
+	if (txq->q.n_bd)
+		pci_free_consistent(dev, sizeof(struct iwl_tfd_frame) *
+				    txq->q.n_bd, txq->bd, txq->q.dma_addr);
+
+	/* De-alloc array of per-TFD driver data */
+	kfree(txq->txb);
+	txq->txb = NULL;
+
+	/* 0-fill queue descriptor structure */
+	memset(txq, 0, sizeof(*txq));
+}
+
+/*************** DMA-QUEUE-GENERAL-FUNCTIONS  *****
+ * DMA services
+ *
+ * Theory of operation
+ *
+ * A Tx or Rx queue resides in host DRAM, and is comprised of a circular buffer
+ * of buffer descriptors, each of which points to one or more data buffers for
+ * the device to read from or fill.  Driver and device exchange status of each
+ * queue via "read" and "write" pointers.  Driver keeps minimum of 2 empty
+ * entries in each circular buffer, to protect against confusing empty and full
+ * queue states.
+ *
+ * The device reads or writes the data in the queues via the device's several
+ * DMA/FIFO channels.  Each queue is mapped to a single DMA channel.
+ *
+ * For Tx queue, there are low mark and high mark limits. If, after queuing
+ * the packet for Tx, free space become < low mark, Tx queue stopped. When
+ * reclaiming packets (on 'tx done IRQ), if free space become > high mark,
+ * Tx queue resumed.
+ *
+ * See more detailed info in iwl-4965-hw.h.
+ ***************************************************/
+
+int iwl_queue_space(const struct iwl_queue *q)
+{
+	int s = q->read_ptr - q->write_ptr;
+
+	if (q->read_ptr > q->write_ptr)
+		s -= q->n_bd;
+
+	if (s <= 0)
+		s += q->n_window;
+	/* keep some reserve to not confuse empty and full situations */
+	s -= 2;
+	if (s < 0)
+		s = 0;
+	return s;
+}
+EXPORT_SYMBOL(iwl_queue_space);
+
+
+/**
+ * iwl_queue_init - Initialize queue's high/low-water and read/write indexes
+ */
+static int iwl_queue_init(struct iwl_priv *priv, struct iwl_queue *q,
+			  int count, int slots_num, u32 id)
+{
+	q->n_bd = count;
+	q->n_window = slots_num;
+	q->id = id;
+
+	/* count must be power-of-two size, otherwise iwl_queue_inc_wrap
+	 * and iwl_queue_dec_wrap are broken. */
+	BUG_ON(!is_power_of_2(count));
+
+	/* slots_num must be power-of-two size, otherwise
+	 * get_cmd_index is broken. */
+	BUG_ON(!is_power_of_2(slots_num));
+
+	q->low_mark = q->n_window / 4;
+	if (q->low_mark < 4)
+		q->low_mark = 4;
+
+	q->high_mark = q->n_window / 8;
+	if (q->high_mark < 2)
+		q->high_mark = 2;
+
+	q->write_ptr = q->read_ptr = 0;
+
+	return 0;
+}
+
+/**
+ * iwl_tx_queue_alloc - Alloc driver data and TFD CB for one Tx/cmd queue
+ */
+static int iwl_tx_queue_alloc(struct iwl_priv *priv,
+			      struct iwl_tx_queue *txq, u32 id)
+{
+	struct pci_dev *dev = priv->pci_dev;
+
+	/* Driver private data, only for Tx (not command) queues,
+	 * not shared with device. */
+	if (id != IWL_CMD_QUEUE_NUM) {
+		txq->txb = kmalloc(sizeof(txq->txb[0]) *
+				   TFD_QUEUE_SIZE_MAX, GFP_KERNEL);
+		if (!txq->txb) {
+			IWL_ERROR("kmalloc for auxiliary BD "
+				  "structures failed\n");
+			goto error;
+		}
+	} else
+		txq->txb = NULL;
+
+	/* Circular buffer of transmit frame descriptors (TFDs),
+	 * shared with device */
+	txq->bd = pci_alloc_consistent(dev,
+			sizeof(txq->bd[0]) * TFD_QUEUE_SIZE_MAX,
+			&txq->q.dma_addr);
+
+	if (!txq->bd) {
+		IWL_ERROR("pci_alloc_consistent(%zd) failed\n",
+			  sizeof(txq->bd[0]) * TFD_QUEUE_SIZE_MAX);
+		goto error;
+	}
+	txq->q.id = id;
+
+	return 0;
+
+ error:
+	kfree(txq->txb);
+	txq->txb = NULL;
+
+	return -ENOMEM;
+}
+
+/*
+ * Tell nic where to find circular buffer of Tx Frame Descriptors for
+ * given Tx queue, and enable the DMA channel used for that queue.
+ *
+ * 4965 supports up to 16 Tx queues in DRAM, mapped to up to 8 Tx DMA
+ * channels supported in hardware.
+ */
+static int iwl_hw_tx_queue_init(struct iwl_priv *priv,
+				struct iwl_tx_queue *txq)
+{
+	int rc;
+	unsigned long flags;
+	int txq_id = txq->q.id;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	rc = iwl_grab_nic_access(priv);
+	if (rc) {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		return rc;
+	}
+
+	/* Circular buffer (TFD queue in DRAM) physical base address */
+	iwl_write_direct32(priv, FH_MEM_CBBC_QUEUE(txq_id),
+			     txq->q.dma_addr >> 8);
+
+	/* Enable DMA channel, using same id as for TFD queue */
+	iwl_write_direct32(
+		priv, FH_TCSR_CHNL_TX_CONFIG_REG(txq_id),
+		FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_ENABLE |
+		FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_ENABLE_VAL);
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return 0;
+}
+
+/**
+ * iwl_tx_queue_init - Allocate and initialize one tx/cmd queue
+ */
+static int iwl_tx_queue_init(struct iwl_priv *priv,
+			     struct iwl_tx_queue *txq,
+			     int slots_num, u32 txq_id)
+{
+	struct pci_dev *dev = priv->pci_dev;
+	int len;
+	int rc = 0;
+
+	/*
+	 * Alloc buffer array for commands (Tx or other types of commands).
+	 * For the command queue (#4), allocate command space + one big
+	 * command for scan, since scan command is very huge; the system will
+	 * not have two scans at the same time, so only one is needed.
+	 * For normal Tx queues (all other queues), no super-size command
+	 * space is needed.
+	 */
+	len = sizeof(struct iwl_cmd) * slots_num;
+	if (txq_id == IWL_CMD_QUEUE_NUM)
+		len +=  IWL_MAX_SCAN_SIZE;
+	txq->cmd = pci_alloc_consistent(dev, len, &txq->dma_addr_cmd);
+	if (!txq->cmd)
+		return -ENOMEM;
+
+	/* Alloc driver data array and TFD circular buffer */
+	rc = iwl_tx_queue_alloc(priv, txq, txq_id);
+	if (rc) {
+		pci_free_consistent(dev, len, txq->cmd, txq->dma_addr_cmd);
+
+		return -ENOMEM;
+	}
+	txq->need_update = 0;
+
+	/* TFD_QUEUE_SIZE_MAX must be power-of-two size, otherwise
+	 * iwl_queue_inc_wrap and iwl_queue_dec_wrap are broken. */
+	BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1));
+
+	/* Initialize queue's high/low-water marks, and head/tail indexes */
+	iwl_queue_init(priv, &txq->q, TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
+
+	/* Tell device where to find queue */
+	iwl_hw_tx_queue_init(priv, txq);
+
+	return 0;
+}
+/**
+ * iwl_hw_txq_ctx_free - Free TXQ Context
+ *
+ * Destroy all TX DMA queues and structures
+ */
+void iwl_hw_txq_ctx_free(struct iwl_priv *priv)
+{
+	int txq_id;
+
+	/* Tx queues */
+	for (txq_id = 0; txq_id < priv->hw_params.max_txq_num; txq_id++)
+		iwl_tx_queue_free(priv, &priv->txq[txq_id]);
+
+	/* Keep-warm buffer */
+	iwl_kw_free(priv);
+}
+EXPORT_SYMBOL(iwl_hw_txq_ctx_free);
+
+
+/**
+ * iwl_txq_ctx_reset - Reset TX queue context
+ * Destroys all DMA structures and initialise them again
+ *
+ * @param priv
+ * @return error code
+ */
+int iwl_txq_ctx_reset(struct iwl_priv *priv)
+{
+	int ret = 0;
+	int txq_id, slots_num;
+	unsigned long flags;
+
+	iwl_kw_free(priv);
+
+	/* Free all tx/cmd queues and keep-warm buffer */
+	iwl_hw_txq_ctx_free(priv);
+
+	/* Alloc keep-warm buffer */
+	ret = iwl_kw_alloc(priv);
+	if (ret) {
+		IWL_ERROR("Keep Warm allocation failed");
+		goto error_kw;
+	}
+	spin_lock_irqsave(&priv->lock, flags);
+	ret = iwl_grab_nic_access(priv);
+	if (unlikely(ret)) {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		goto error_reset;
+	}
+
+	/* Turn off all Tx DMA fifos */
+	priv->cfg->ops->lib->txq_set_sched(priv, 0);
+
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+
+	/* Tell nic where to find the keep-warm buffer */
+	ret = iwl_kw_init(priv);
+	if (ret) {
+		IWL_ERROR("kw_init failed\n");
+		goto error_reset;
+	}
+
+	/* 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 == IWL_CMD_QUEUE_NUM) ?
+					TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
+		ret = iwl_tx_queue_init(priv, &priv->txq[txq_id], slots_num,
+				       txq_id);
+		if (ret) {
+			IWL_ERROR("Tx %d queue init failed\n", txq_id);
+			goto error;
+		}
+	}
+
+	return ret;
+
+ error:
+	iwl_hw_txq_ctx_free(priv);
+ error_reset:
+	iwl_kw_free(priv);
+ error_kw:
+	return ret;
+}
+/**
+ * iwl_txq_ctx_stop - Stop all Tx DMA channels, free Tx queue memory
+ */
+void iwl_txq_ctx_stop(struct iwl_priv *priv)
+{
+
+	int txq_id;
+	unsigned long flags;
+
+
+	/* Turn off all Tx DMA fifos */
+	spin_lock_irqsave(&priv->lock, flags);
+	if (iwl_grab_nic_access(priv)) {
+		spin_unlock_irqrestore(&priv->lock, flags);
+		return;
+	}
+
+	priv->cfg->ops->lib->txq_set_sched(priv, 0);
+
+	/* Stop each Tx DMA channel, and wait for it to be idle */
+	for (txq_id = 0; txq_id < priv->hw_params.max_txq_num; txq_id++) {
+		iwl_write_direct32(priv,
+				   FH_TCSR_CHNL_TX_CONFIG_REG(txq_id), 0x0);
+		iwl_poll_direct_bit(priv, FH_TSSR_TX_STATUS_REG,
+				    FH_TSSR_TX_STATUS_REG_MSK_CHNL_IDLE
+				    (txq_id), 200);
+	}
+	iwl_release_nic_access(priv);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/* Deallocate memory for all Tx queues */
+	iwl_hw_txq_ctx_free(priv);
+}
+EXPORT_SYMBOL(iwl_txq_ctx_stop);
+
+/*
+ * handle build REPLY_TX command notification.
+ */
+static void iwl_tx_cmd_build_basic(struct iwl_priv *priv,
+				  struct iwl_tx_cmd *tx_cmd,
+				  struct ieee80211_tx_info *info,
+				  struct ieee80211_hdr *hdr,
+				  int is_unicast, 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;
+	}
+
+	priv->cfg->ops->utils->rts_tx_cmd_flag(info, &tx_flags);
+
+	if ((tx_flags & TX_CMD_FLG_RTS_MSK) || (tx_flags & TX_CMD_FLG_CTS_MSK))
+		tx_flags |= TX_CMD_FLG_FULL_TXOP_PROT_MSK;
+
+	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_HCCA_RETRY_LIMIT		3
+#define RTS_DFAULT_RETRY_LIMIT		60
+
+static void iwl_tx_cmd_build_rate(struct iwl_priv *priv,
+			      struct iwl_tx_cmd *tx_cmd,
+			      struct ieee80211_tx_info *info,
+			      __le16 fc, int sta_id,
+			      int is_hcca)
+{
+	u8 rts_retry_limit = 0;
+	u8 data_retry_limit = 0;
+	u8 rate_plcp;
+	u16 rate_flags = 0;
+	int rate_idx;
+
+	rate_idx = min(ieee80211_get_tx_rate(priv->hw, info)->hw_value & 0xffff,
+			IWL_RATE_COUNT - 1);
+
+	rate_plcp = iwl_rates[rate_idx].plcp;
+
+	rts_retry_limit = (is_hcca) ?
+	    RTS_HCCA_RETRY_LIMIT : RTS_DFAULT_RETRY_LIMIT;
+
+	if ((rate_idx >= IWL_FIRST_CCK_RATE) && (rate_idx <= IWL_LAST_CCK_RATE))
+		rate_flags |= RATE_MCS_CCK_MSK;
+
+
+	if (ieee80211_is_probe_resp(fc)) {
+		data_retry_limit = 3;
+		if (data_retry_limit < rts_retry_limit)
+			rts_retry_limit = data_retry_limit;
+	} else
+		data_retry_limit = IWL_DEFAULT_TX_RETRY;
+
+	if (priv->data_retry_limit != -1)
+		data_retry_limit = priv->data_retry_limit;
+
+
+	if (ieee80211_is_data(fc)) {
+		tx_cmd->initial_rate_index = 0;
+		tx_cmd->tx_flags |= TX_CMD_FLG_STA_RATE_MSK;
+	} else {
+		switch (fc & cpu_to_le16(IEEE80211_FCTL_STYPE)) {
+		case cpu_to_le16(IEEE80211_STYPE_AUTH):
+		case cpu_to_le16(IEEE80211_STYPE_DEAUTH):
+		case cpu_to_le16(IEEE80211_STYPE_ASSOC_REQ):
+		case cpu_to_le16(IEEE80211_STYPE_REASSOC_REQ):
+			if (tx_cmd->tx_flags & TX_CMD_FLG_RTS_MSK) {
+				tx_cmd->tx_flags &= ~TX_CMD_FLG_RTS_MSK;
+				tx_cmd->tx_flags |= TX_CMD_FLG_CTS_MSK;
+			}
+			break;
+		default:
+			break;
+		}
+
+		/* Alternate between antenna A and B for successive frames */
+		if (priv->use_ant_b_for_management_frame) {
+			priv->use_ant_b_for_management_frame = 0;
+			rate_flags |= RATE_MCS_ANT_B_MSK;
+		} else {
+			priv->use_ant_b_for_management_frame = 1;
+			rate_flags |= RATE_MCS_ANT_A_MSK;
+		}
+	}
+
+	tx_cmd->rts_retry_limit = rts_retry_limit;
+	tx_cmd->data_retry_limit = data_retry_limit;
+	tx_cmd->rate_n_flags = iwl_hw_set_rate_n_flags(rate_plcp, rate_flags);
+}
+
+static void iwl_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->alg) {
+	case ALG_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("tx_cmd with aes hwcrypto\n");
+		break;
+
+	case ALG_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("tx_cmd with tkip hwcrypto\n");
+		break;
+
+	case ALG_WEP:
+		tx_cmd->sec_ctl |= (TX_CMD_SEC_WEP |
+			(keyconf->keyidx & TX_CMD_SEC_MSK) << TX_CMD_SEC_SHIFT);
+
+		if (keyconf->keylen == WEP_KEY_LEN_128)
+			tx_cmd->sec_ctl |= TX_CMD_SEC_KEY128;
+
+		memcpy(&tx_cmd->key[3], keyconf->key, keyconf->keylen);
+
+		IWL_DEBUG_TX("Configuring packet for WEP encryption "
+			     "with key %d\n", keyconf->keyidx);
+		break;
+
+	default:
+		printk(KERN_ERR "Unknown encode alg %d\n", keyconf->alg);
+		break;
+	}
+}
+
+static void iwl_update_tx_stats(struct iwl_priv *priv, u16 fc, u16 len)
+{
+	/* 0 - mgmt, 1 - cnt, 2 - data */
+	int idx = (fc & IEEE80211_FCTL_FTYPE) >> 2;
+	priv->tx_stats[idx].cnt++;
+	priv->tx_stats[idx].bytes += len;
+}
+
+/*
+ * start REPLY_TX command process
+ */
+int iwl_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 iwl_tfd_frame *tfd;
+	u32 *control_flags;
+	int txq_id = skb_get_queue_mapping(skb);
+	struct iwl_tx_queue *txq = NULL;
+	struct iwl_queue *q = NULL;
+	dma_addr_t phys_addr;
+	dma_addr_t txcmd_phys;
+	dma_addr_t scratch_phys;
+	struct iwl_cmd *out_cmd = NULL;
+	struct iwl_tx_cmd *tx_cmd;
+	u16 len, idx, len_org;
+	u16 seq_number = 0;
+	u8 id, hdr_len, unicast;
+	u8 sta_id;
+	__le16 fc;
+	u8 wait_write_ptr = 0;
+	u8 tid = 0;
+	u8 *qc = NULL;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (iwl_is_rfkill(priv)) {
+		IWL_DEBUG_DROP("Dropping - RF KILL\n");
+		goto drop_unlock;
+	}
+
+	if (!priv->vif) {
+		IWL_DEBUG_DROP("Dropping - !priv->vif\n");
+		goto drop_unlock;
+	}
+
+	if ((ieee80211_get_tx_rate(priv->hw, info)->hw_value & 0xFF) ==
+	     IWL_INVALID_RATE) {
+		IWL_ERROR("ERROR: No TX rate available.\n");
+		goto drop_unlock;
+	}
+
+	unicast = !is_multicast_ether_addr(hdr->addr1);
+	id = 0;
+
+	fc = hdr->frame_control;
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+	if (ieee80211_is_auth(fc))
+		IWL_DEBUG_TX("Sending AUTH frame\n");
+	else if (ieee80211_is_assoc_req(fc))
+		IWL_DEBUG_TX("Sending ASSOC frame\n");
+	else if (ieee80211_is_reassoc_req(fc))
+		IWL_DEBUG_TX("Sending REASSOC frame\n");
+#endif
+
+	/* drop all data frame if we are not associated */
+	if (ieee80211_is_data(fc) &&
+	   (!iwl_is_associated(priv) ||
+	    ((priv->iw_mode == IEEE80211_IF_TYPE_STA) && !priv->assoc_id) ||
+	    !priv->assoc_station_added)) {
+		IWL_DEBUG_DROP("Dropping - !iwl_is_associated\n");
+		goto drop_unlock;
+	}
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	hdr_len = ieee80211_get_hdrlen(le16_to_cpu(fc));
+
+	/* Find (or create) index into station table for destination station */
+	sta_id = iwl_get_sta_id(priv, hdr);
+	if (sta_id == IWL_INVALID_STATION) {
+		DECLARE_MAC_BUF(mac);
+
+		IWL_DEBUG_DROP("Dropping - INVALID STATION: %s\n",
+			       print_mac(mac, hdr->addr1));
+		goto drop;
+	}
+
+	IWL_DEBUG_TX("station Id %d\n", sta_id);
+
+	if (ieee80211_is_data_qos(fc)) {
+		qc = ieee80211_get_qos_ctl(hdr);
+		tid = qc[0] & 0xf;
+		seq_number = priv->stations[sta_id].tid[tid].seq_number &
+				IEEE80211_SCTL_SEQ;
+		hdr->seq_ctrl = cpu_to_le16(seq_number) |
+			(hdr->seq_ctrl &
+				__constant_cpu_to_le16(IEEE80211_SCTL_FRAG));
+		seq_number += 0x10;
+		/* aggregation is on for this <sta,tid> */
+		if (info->flags & IEEE80211_TX_CTL_AMPDU)
+			txq_id = priv->stations[sta_id].tid[tid].agg.txq_id;
+		priv->stations[sta_id].tid[tid].tfds_in_queue++;
+	}
+
+	/* Descriptor for chosen Tx queue */
+	txq = &priv->txq[txq_id];
+	q = &txq->q;
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Set up first empty TFD within this queue's circular TFD buffer */
+	tfd = &txq->bd[q->write_ptr];
+	memset(tfd, 0, sizeof(*tfd));
+	control_flags = (u32 *) tfd;
+	idx = get_cmd_index(q, q->write_ptr, 0);
+
+	/* 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[0] = skb;
+
+	/* Set up first empty entry in queue's array of Tx/cmd buffers */
+	out_cmd = &txq->cmd[idx];
+	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);
+
+	/*
+	 * 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;
+
+	len_org = len;
+	len = (len + 3) & ~3;
+
+	if (len_org != len)
+		len_org = 1;
+	else
+		len_org = 0;
+
+	/* Physical address of this Tx command's header (not MAC header!),
+	 * within command buffer array. */
+	txcmd_phys = txq->dma_addr_cmd + sizeof(struct iwl_cmd) * idx +
+		     offsetof(struct iwl_cmd, hdr);
+
+	/* Add buffer containing Tx command and MAC(!) header to TFD's
+	 * first entry */
+	iwl_hw_txq_attach_buf_to_tfd(priv, tfd, txcmd_phys, len);
+
+	if (!(info->flags & IEEE80211_TX_CTL_DO_NOT_ENCRYPT))
+		iwl_tx_cmd_build_hwcrypto(priv, info, tx_cmd, skb, sta_id);
+
+	/* Set up TFD's 2nd entry to point directly to remainder of skb,
+	 * if any (802.11 null frames have no payload). */
+	len = skb->len - hdr_len;
+	if (len) {
+		phys_addr = pci_map_single(priv->pci_dev, skb->data + hdr_len,
+					   len, PCI_DMA_TODEVICE);
+		iwl_hw_txq_attach_buf_to_tfd(priv, tfd, phys_addr, len);
+	}
+
+	/* Tell NIC about any 2-byte padding after MAC header */
+	if (len_org)
+		tx_cmd->tx_flags |= TX_CMD_FLG_MH_PAD_MSK;
+
+	/* Total # bytes to be transmitted */
+	len = (u16)skb->len;
+	tx_cmd->len = cpu_to_le16(len);
+	/* TODO need this for burst mode later on */
+	iwl_tx_cmd_build_basic(priv, tx_cmd, info, hdr, unicast, sta_id);
+
+	/* set is_hcca to 0; it probably will never be implemented */
+	iwl_tx_cmd_build_rate(priv, tx_cmd, info, fc, sta_id, 0);
+
+	iwl_update_tx_stats(priv, le16_to_cpu(fc), len);
+
+	scratch_phys = txcmd_phys + sizeof(struct iwl_cmd_header) +
+		offsetof(struct iwl_tx_cmd, scratch);
+	tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
+	tx_cmd->dram_msb_ptr = iwl_get_dma_hi_address(scratch_phys);
+
+	if (!ieee80211_has_morefrags(hdr->frame_control)) {
+		txq->need_update = 1;
+		if (qc)
+			priv->stations[sta_id].tid[tid].seq_number = seq_number;
+	} else {
+		wait_write_ptr = 1;
+		txq->need_update = 0;
+	}
+
+	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 */
+	priv->cfg->ops->lib->txq_update_byte_cnt_tbl(priv, txq, len);
+
+	/* Tell device the write index *just past* this latest filled TFD */
+	q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
+	ret = iwl_txq_update_write_ptr(priv, txq);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (ret)
+		return ret;
+
+	if ((iwl_queue_space(q) < q->high_mark)
+	    && priv->mac80211_registered) {
+		if (wait_write_ptr) {
+			spin_lock_irqsave(&priv->lock, flags);
+			txq->need_update = 1;
+			iwl_txq_update_write_ptr(priv, txq);
+			spin_unlock_irqrestore(&priv->lock, flags);
+		}
+
+		ieee80211_stop_queue(priv->hw, skb_get_queue_mapping(skb));
+	}
+
+	return 0;
+
+drop_unlock:
+	spin_unlock_irqrestore(&priv->lock, flags);
+drop:
+	return -1;
+}
+EXPORT_SYMBOL(iwl_tx_skb);
+
+/*************** HOST COMMAND QUEUE FUNCTIONS   *****/
+
+/**
+ * iwl_enqueue_hcmd - enqueue a uCode command
+ * @priv: device private data point
+ * @cmd: a point to the ucode command structure
+ *
+ * The function returns < 0 values to indicate the operation is
+ * failed. On success, it turns the index (> 0) of command in the
+ * command queue.
+ */
+int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
+{
+	struct iwl_tx_queue *txq = &priv->txq[IWL_CMD_QUEUE_NUM];
+	struct iwl_queue *q = &txq->q;
+	struct iwl_tfd_frame *tfd;
+	u32 *control_flags;
+	struct iwl_cmd *out_cmd;
+	u32 idx;
+	u16 fix_size;
+	dma_addr_t phys_addr;
+	int ret;
+	unsigned long flags;
+
+	cmd->len = priv->cfg->ops->utils->get_hcmd_size(cmd->id, cmd->len);
+	fix_size = (u16)(cmd->len + sizeof(out_cmd->hdr));
+
+	/* If any of the command structures end up being larger than
+	 * the TFD_MAX_PAYLOAD_SIZE, and it sent as a 'small' command then
+	 * we will need to increase the size of the TFD entries */
+	BUG_ON((fix_size > TFD_MAX_PAYLOAD_SIZE) &&
+	       !(cmd->meta.flags & CMD_SIZE_HUGE));
+
+	if (iwl_is_rfkill(priv)) {
+		IWL_DEBUG_INFO("Not sending command - RF KILL");
+		return -EIO;
+	}
+
+	if (iwl_queue_space(q) < ((cmd->meta.flags & CMD_ASYNC) ? 2 : 1)) {
+		IWL_ERROR("No space for Tx\n");
+		return -ENOSPC;
+	}
+
+	spin_lock_irqsave(&priv->hcmd_lock, flags);
+
+	tfd = &txq->bd[q->write_ptr];
+	memset(tfd, 0, sizeof(*tfd));
+
+	control_flags = (u32 *) tfd;
+
+	idx = get_cmd_index(q, q->write_ptr, cmd->meta.flags & CMD_SIZE_HUGE);
+	out_cmd = &txq->cmd[idx];
+
+	out_cmd->hdr.cmd = cmd->id;
+	memcpy(&out_cmd->meta, &cmd->meta, sizeof(cmd->meta));
+	memcpy(&out_cmd->cmd.payload, cmd->data, cmd->len);
+
+	/* At this point, the out_cmd now has all of the incoming cmd
+	 * information */
+
+	out_cmd->hdr.flags = 0;
+	out_cmd->hdr.sequence = cpu_to_le16(QUEUE_TO_SEQ(IWL_CMD_QUEUE_NUM) |
+			INDEX_TO_SEQ(q->write_ptr));
+	if (out_cmd->meta.flags & CMD_SIZE_HUGE)
+		out_cmd->hdr.sequence |= cpu_to_le16(SEQ_HUGE_FRAME);
+
+	phys_addr = txq->dma_addr_cmd + sizeof(txq->cmd[0]) * idx +
+			offsetof(struct iwl_cmd, hdr);
+	iwl_hw_txq_attach_buf_to_tfd(priv, tfd, phys_addr, fix_size);
+
+	IWL_DEBUG_HC("Sending command %s (#%x), seq: 0x%04X, "
+		     "%d bytes at %d[%d]:%d\n",
+		     get_cmd_string(out_cmd->hdr.cmd),
+		     out_cmd->hdr.cmd, le16_to_cpu(out_cmd->hdr.sequence),
+		     fix_size, q->write_ptr, idx, IWL_CMD_QUEUE_NUM);
+
+	txq->need_update = 1;
+
+	/* Set up entry in queue's byte count circular buffer */
+	priv->cfg->ops->lib->txq_update_byte_cnt_tbl(priv, txq, 0);
+
+	/* Increment and update queue's write index */
+	q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
+	ret = iwl_txq_update_write_ptr(priv, txq);
+
+	spin_unlock_irqrestore(&priv->hcmd_lock, flags);
+	return ret ? ret : idx;
+}
+
+int iwl_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;
+
+	if ((index >= q->n_bd) || (iwl_queue_used(q, index) == 0)) {
+		IWL_ERROR("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_queue_inc_wrap(index, q->n_bd); q->read_ptr != index;
+		q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) {
+
+		tx_info = &txq->txb[txq->q.read_ptr];
+		ieee80211_tx_status_irqsafe(priv->hw, tx_info->skb[0]);
+		tx_info->skb[0] = NULL;
+
+		if (priv->cfg->ops->lib->txq_inval_byte_cnt_tbl)
+			priv->cfg->ops->lib->txq_inval_byte_cnt_tbl(priv, txq);
+
+		iwl_hw_txq_free_tfd(priv, txq);
+		nfreed++;
+	}
+	return nfreed;
+}
+EXPORT_SYMBOL(iwl_tx_queue_reclaim);
+
+
+/**
+ * iwl_hcmd_queue_reclaim - Reclaim TX command queue entries already Tx'd
+ *
+ * When FW advances 'R' index, all entries between old and new 'R' index
+ * need to be reclaimed. As result, some free space forms.  If there is
+ * enough free space (> low mark), wake the stack that feeds us.
+ */
+static void iwl_hcmd_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;
+	int nfreed = 0;
+
+	if ((index >= q->n_bd) || (iwl_queue_used(q, index) == 0)) {
+		IWL_ERROR("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;
+	}
+
+	for (index = iwl_queue_inc_wrap(index, q->n_bd); q->read_ptr != index;
+		q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) {
+
+		if (nfreed > 1) {
+			IWL_ERROR("HCMD skipped: index (%d) %d %d\n", index,
+					q->write_ptr, q->read_ptr);
+			queue_work(priv->workqueue, &priv->restart);
+		}
+		nfreed++;
+	}
+}
+
+/**
+ * iwl_tx_cmd_complete - Pull unused buffers off the queue and reclaim them
+ * @rxb: Rx buffer to reclaim
+ *
+ * If an Rx buffer has an async callback associated with it the callback
+ * will be executed.  The attached skb (if present) will only be freed
+ * if the callback returns 1
+ */
+void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb)
+{
+	struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
+	u16 sequence = le16_to_cpu(pkt->hdr.sequence);
+	int txq_id = SEQ_TO_QUEUE(sequence);
+	int index = SEQ_TO_INDEX(sequence);
+	int huge = sequence & SEQ_HUGE_FRAME;
+	int cmd_index;
+	struct iwl_cmd *cmd;
+
+	/* If a Tx command is being handled and it isn't in the actual
+	 * command queue then there a command routing bug has been introduced
+	 * in the queue management code. */
+	if (txq_id != IWL_CMD_QUEUE_NUM)
+		IWL_ERROR("Error wrong command queue %d command id 0x%X\n",
+			  txq_id, pkt->hdr.cmd);
+	BUG_ON(txq_id != IWL_CMD_QUEUE_NUM);
+
+	cmd_index = get_cmd_index(&priv->txq[IWL_CMD_QUEUE_NUM].q, index, huge);
+	cmd = &priv->txq[IWL_CMD_QUEUE_NUM].cmd[cmd_index];
+
+	/* Input error checking is done when commands are added to queue. */
+	if (cmd->meta.flags & CMD_WANT_SKB) {
+		cmd->meta.source->u.skb = rxb->skb;
+		rxb->skb = NULL;
+	} else if (cmd->meta.u.callback &&
+		   !cmd->meta.u.callback(priv, cmd, rxb->skb))
+		rxb->skb = NULL;
+
+	iwl_hcmd_queue_reclaim(priv, txq_id, index);
+
+	if (!(cmd->meta.flags & CMD_ASYNC)) {
+		clear_bit(STATUS_HCMD_ACTIVE, &priv->status);
+		wake_up_interruptible(&priv->wait_command_queue);
+	}
+}
+EXPORT_SYMBOL(iwl_tx_cmd_complete);
+
+/*
+ * 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), HCCA (5, 6).
+ */
+static int iwl_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;
+}
+
+int iwl_tx_agg_start(struct iwl_priv *priv, const u8 *ra, u16 tid, u16 *ssn)
+{
+	int sta_id;
+	int tx_fifo;
+	int txq_id;
+	int ret;
+	unsigned long flags;
+	struct iwl_tid_data *tid_data;
+	DECLARE_MAC_BUF(mac);
+
+	if (likely(tid < ARRAY_SIZE(default_tid_to_tx_fifo)))
+		tx_fifo = default_tid_to_tx_fifo[tid];
+	else
+		return -EINVAL;
+
+	IWL_WARNING("%s on ra = %s tid = %d\n",
+			__func__, print_mac(mac, ra), tid);
+
+	sta_id = iwl_find_station(priv, ra);
+	if (sta_id == IWL_INVALID_STATION)
+		return -ENXIO;
+
+	if (priv->stations[sta_id].tid[tid].agg.state != IWL_AGG_OFF) {
+		IWL_ERROR("Start AGG when state is not IWL_AGG_OFF !\n");
+		return -ENXIO;
+	}
+
+	txq_id = iwl_txq_ctx_activate_free(priv);
+	if (txq_id == -1)
+		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;
+	spin_unlock_irqrestore(&priv->sta_lock, flags);
+
+	ret = priv->cfg->ops->lib->txq_agg_enable(priv, txq_id, tx_fifo,
+						  sta_id, tid, *ssn);
+	if (ret)
+		return ret;
+
+	if (tid_data->tfds_in_queue == 0) {
+		printk(KERN_ERR "HW queue is empty\n");
+		tid_data->agg.state = IWL_AGG_ON;
+		ieee80211_start_tx_ba_cb_irqsafe(priv->hw, ra, tid);
+	} else {
+		IWL_DEBUG_HT("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;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(iwl_tx_agg_start);
+
+int iwl_tx_agg_stop(struct iwl_priv *priv , const u8 *ra, u16 tid)
+{
+	int tx_fifo_id, txq_id, sta_id, ssn = -1;
+	struct iwl_tid_data *tid_data;
+	int ret, write_ptr, read_ptr;
+	unsigned long flags;
+	DECLARE_MAC_BUF(mac);
+
+	if (!ra) {
+		IWL_ERROR("ra = NULL\n");
+		return -EINVAL;
+	}
+
+	if (likely(tid < ARRAY_SIZE(default_tid_to_tx_fifo)))
+		tx_fifo_id = default_tid_to_tx_fifo[tid];
+	else
+		return -EINVAL;
+
+	sta_id = iwl_find_station(priv, ra);
+
+	if (sta_id == IWL_INVALID_STATION)
+		return -ENXIO;
+
+	if (priv->stations[sta_id].tid[tid].agg.state != IWL_AGG_ON)
+		IWL_WARNING("Stopping AGG while state not IWL_AGG_ON\n");
+
+	tid_data = &priv->stations[sta_id].tid[tid];
+	ssn = (tid_data->seq_number & IEEE80211_SCTL_SEQ) >> 4;
+	txq_id = tid_data->agg.txq_id;
+	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("Stopping a non empty AGG HW QUEUE\n");
+		priv->stations[sta_id].tid[tid].agg.state =
+				IWL_EMPTYING_HW_QUEUE_DELBA;
+		return 0;
+	}
+
+	IWL_DEBUG_HT("HW queue is empty\n");
+	priv->stations[sta_id].tid[tid].agg.state = IWL_AGG_OFF;
+
+	spin_lock_irqsave(&priv->lock, flags);
+	ret = priv->cfg->ops->lib->txq_agg_disable(priv, txq_id, ssn,
+						   tx_fifo_id);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (ret)
+		return ret;
+
+	ieee80211_stop_tx_ba_cb_irqsafe(priv->hw, ra, tid);
+
+	return 0;
+}
+EXPORT_SYMBOL(iwl_tx_agg_stop);
+
+int iwl_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];
+
+	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 = default_tid_to_tx_fifo[tid];
+			IWL_DEBUG_HT("HW queue empty: continue DELBA flow\n");
+			priv->cfg->ops->lib->txq_agg_disable(priv, txq_id,
+							     ssn, tx_fifo);
+			tid_data->agg.state = IWL_AGG_OFF;
+			ieee80211_stop_tx_ba_cb_irqsafe(priv->hw, 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("HW queue empty: continue ADDBA flow\n");
+			tid_data->agg.state = IWL_AGG_ON;
+			ieee80211_start_tx_ba_cb_irqsafe(priv->hw, addr, tid);
+		}
+		break;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(iwl_txq_check_empty);
+
+/**
+ * iwl_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 iwl_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);
+	u64 bitmap;
+	int successes = 0;
+	struct ieee80211_tx_info *info;
+
+	if (unlikely(!agg->wait_for_ba))  {
+		IWL_ERROR("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("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;
+
+	/* don't use 64-bit values for now */
+	bitmap = le64_to_cpu(ba_resp->bitmap) >> sh;
+
+	if (agg->frame_count > (64 - sh)) {
+		IWL_DEBUG_TX_REPLY("more frames than bitmap size");
+		return -1;
+	}
+
+	/* check for success or failure according to the
+	 * transmitted bitmap and block-ack bitmap */
+	bitmap &= agg->bitmap;
+
+	/* For each frame attempted in aggregation,
+	 * update driver's record of tx frame's status. */
+	for (i = 0; i < agg->frame_count ; i++) {
+		ack = bitmap & (1 << i);
+		successes += !!ack;
+		IWL_DEBUG_TX_REPLY("%s ON i=%d idx=%d raw=%d\n",
+			ack? "ACK":"NACK", i, (agg->start_idx + i) & 0xff,
+			agg->start_idx + i);
+	}
+
+	info = IEEE80211_SKB_CB(priv->txq[scd_flow].txb[agg->start_idx].skb[0]);
+	memset(&info->status, 0, sizeof(info->status));
+	info->flags = IEEE80211_TX_STAT_ACK;
+	info->flags |= IEEE80211_TX_STAT_AMPDU;
+	info->status.ampdu_ack_map = successes;
+	info->status.ampdu_ack_len = agg->frame_count;
+	iwl_hwrate_to_tx_control(priv, agg->rate_n_flags, info);
+
+	IWL_DEBUG_TX_REPLY("Bitmap %llx\n", (unsigned long long)bitmap);
+
+	return 0;
+}
+
+/**
+ * iwl_rx_reply_compressed_ba - Handler for REPLY_COMPRESSED_BA
+ *
+ * Handles block-acknowledge notification from device, which reports success
+ * of frames sent via aggregation.
+ */
+void iwl_rx_reply_compressed_ba(struct iwl_priv *priv,
+					   struct iwl_rx_mem_buffer *rxb)
+{
+	struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
+	struct iwl_compressed_ba_resp *ba_resp = &pkt->u.compressed_ba;
+	int index;
+	struct iwl_tx_queue *txq = NULL;
+	struct iwl_ht_agg *agg;
+	DECLARE_MAC_BUF(mac);
+
+	/* "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_ERROR("BUG_ON scd_flow is bigger than number of queues");
+		return;
+	}
+
+	txq = &priv->txq[scd_flow];
+	agg = &priv->stations[ba_resp->sta_id].tid[ba_resp->tid].agg;
+
+	/* Find index just before block-ack window */
+	index = iwl_queue_dec_wrap(ba_resp_scd_ssn & 0xff, txq->q.n_bd);
+
+	/* TODO: Need to get this copy more safely - now good for debug */
+
+	IWL_DEBUG_TX_REPLY("REPLY_COMPRESSED_BA [%d]Received from %s, "
+			   "sta_id = %d\n",
+			   agg->wait_for_ba,
+			   print_mac(mac, (u8 *) &ba_resp->sta_addr_lo32),
+			   ba_resp->sta_id);
+	IWL_DEBUG_TX_REPLY("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("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 */
+	iwl_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 ampdu_q =
+		   scd_flow - priv->hw_params.first_ampdu_q + priv->hw->queues;
+		int freed = iwl_tx_queue_reclaim(priv, scd_flow, index);
+		priv->stations[ba_resp->sta_id].
+			tid[ba_resp->tid].tfds_in_queue -= freed;
+		if (iwl_queue_space(&txq->q) > txq->q.low_mark &&
+			priv->mac80211_registered &&
+			agg->state != IWL_EMPTYING_HW_QUEUE_DELBA)
+			ieee80211_wake_queue(priv->hw, ampdu_q);
+
+		iwl_txq_check_empty(priv, ba_resp->sta_id,
+				    ba_resp->tid, scd_flow);
+	}
+}
+EXPORT_SYMBOL(iwl_rx_reply_compressed_ba);
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+#define TX_STATUS_ENTRY(x) case TX_STATUS_FAIL_ ## x: return #x
+
+const char *iwl_get_tx_fail_reason(u32 status)
+{
+	switch (status & TX_STATUS_MSK) {
+	case TX_STATUS_SUCCESS:
+		return "SUCCESS";
+		TX_STATUS_ENTRY(SHORT_LIMIT);
+		TX_STATUS_ENTRY(LONG_LIMIT);
+		TX_STATUS_ENTRY(FIFO_UNDERRUN);
+		TX_STATUS_ENTRY(MGMNT_ABORT);
+		TX_STATUS_ENTRY(NEXT_FRAG);
+		TX_STATUS_ENTRY(LIFE_EXPIRE);
+		TX_STATUS_ENTRY(DEST_PS);
+		TX_STATUS_ENTRY(ABORTED);
+		TX_STATUS_ENTRY(BT_RETRY);
+		TX_STATUS_ENTRY(STA_INVALID);
+		TX_STATUS_ENTRY(FRAG_DROPPED);
+		TX_STATUS_ENTRY(TID_DISABLE);
+		TX_STATUS_ENTRY(FRAME_FLUSHED);
+		TX_STATUS_ENTRY(INSUFFICIENT_CF_POLL);
+		TX_STATUS_ENTRY(TX_LOCKED);
+		TX_STATUS_ENTRY(NO_BEACON_ON_RADAR);
+	}
+
+	return "UNKNOWN";
+}
+EXPORT_SYMBOL(iwl_get_tx_fail_reason);
+#endif /* CONFIG_IWLWIFI_DEBUG */