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path: root/drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c
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Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c')
-rw-r--r--drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c1165
1 files changed, 1165 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c
new file mode 100644
index 000000000000..5332aa3961b0
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-tx.c
@@ -0,0 +1,1165 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2003 - 2011 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:
+ * Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+#include <linux/etherdevice.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+
+/* TODO: remove include to iwl-dev.h */
+#include "iwl-dev.h"
+#include "iwl-debug.h"
+#include "iwl-csr.h"
+#include "iwl-prph.h"
+#include "iwl-io.h"
+#include "iwl-agn-hw.h"
+#include "iwl-helpers.h"
+#include "iwl-trans-pcie-int.h"
+
+#define IWL_TX_CRC_SIZE 4
+#define IWL_TX_DELIMITER_SIZE 4
+
+/**
+ * iwl_trans_txq_update_byte_cnt_tbl - Set up entry in Tx byte-count array
+ */
+void iwl_trans_txq_update_byte_cnt_tbl(struct iwl_trans *trans,
+ struct iwl_tx_queue *txq,
+ u16 byte_cnt)
+{
+ struct iwlagn_scd_bc_tbl *scd_bc_tbl;
+ struct iwl_trans_pcie *trans_pcie =
+ IWL_TRANS_GET_PCIE_TRANS(trans);
+ int write_ptr = txq->q.write_ptr;
+ int txq_id = txq->q.id;
+ u8 sec_ctl = 0;
+ u8 sta_id = 0;
+ u16 len = byte_cnt + IWL_TX_CRC_SIZE + IWL_TX_DELIMITER_SIZE;
+ __le16 bc_ent;
+
+ scd_bc_tbl = trans_pcie->scd_bc_tbls.addr;
+
+ WARN_ON(len > 0xFFF || write_ptr >= TFD_QUEUE_SIZE_MAX);
+
+ sta_id = txq->cmd[txq->q.write_ptr]->cmd.tx.sta_id;
+ sec_ctl = txq->cmd[txq->q.write_ptr]->cmd.tx.sec_ctl;
+
+ switch (sec_ctl & TX_CMD_SEC_MSK) {
+ case TX_CMD_SEC_CCM:
+ len += CCMP_MIC_LEN;
+ break;
+ case TX_CMD_SEC_TKIP:
+ len += TKIP_ICV_LEN;
+ break;
+ case TX_CMD_SEC_WEP:
+ len += WEP_IV_LEN + WEP_ICV_LEN;
+ break;
+ }
+
+ bc_ent = cpu_to_le16((len & 0xFFF) | (sta_id << 12));
+
+ scd_bc_tbl[txq_id].tfd_offset[write_ptr] = bc_ent;
+
+ if (write_ptr < TFD_QUEUE_SIZE_BC_DUP)
+ scd_bc_tbl[txq_id].
+ tfd_offset[TFD_QUEUE_SIZE_MAX + write_ptr] = bc_ent;
+}
+
+/**
+ * iwl_txq_update_write_ptr - Send new write index to hardware
+ */
+void iwl_txq_update_write_ptr(struct iwl_trans *trans, struct iwl_tx_queue *txq)
+{
+ u32 reg = 0;
+ int txq_id = txq->q.id;
+
+ if (txq->need_update == 0)
+ return;
+
+ if (hw_params(trans).shadow_reg_enable) {
+ /* shadow register enabled */
+ iwl_write32(bus(trans), HBUS_TARG_WRPTR,
+ txq->q.write_ptr | (txq_id << 8));
+ } else {
+ /* if we're trying to save power */
+ if (test_bit(STATUS_POWER_PMI, &trans->shrd->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(bus(trans), CSR_UCODE_DRV_GP1);
+
+ if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
+ IWL_DEBUG_INFO(trans,
+ "Tx queue %d requesting wakeup,"
+ " GP1 = 0x%x\n", txq_id, reg);
+ iwl_set_bit(bus(trans), CSR_GP_CNTRL,
+ CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+ return;
+ }
+
+ iwl_write_direct32(bus(trans), HBUS_TARG_WRPTR,
+ txq->q.write_ptr | (txq_id << 8));
+
+ /*
+ * 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(bus(trans), HBUS_TARG_WRPTR,
+ txq->q.write_ptr | (txq_id << 8));
+ }
+ txq->need_update = 0;
+}
+
+static inline dma_addr_t iwl_tfd_tb_get_addr(struct iwl_tfd *tfd, u8 idx)
+{
+ struct iwl_tfd_tb *tb = &tfd->tbs[idx];
+
+ dma_addr_t addr = get_unaligned_le32(&tb->lo);
+ if (sizeof(dma_addr_t) > sizeof(u32))
+ addr |=
+ ((dma_addr_t)(le16_to_cpu(tb->hi_n_len) & 0xF) << 16) << 16;
+
+ return addr;
+}
+
+static inline u16 iwl_tfd_tb_get_len(struct iwl_tfd *tfd, u8 idx)
+{
+ struct iwl_tfd_tb *tb = &tfd->tbs[idx];
+
+ return le16_to_cpu(tb->hi_n_len) >> 4;
+}
+
+static inline void iwl_tfd_set_tb(struct iwl_tfd *tfd, u8 idx,
+ dma_addr_t addr, u16 len)
+{
+ struct iwl_tfd_tb *tb = &tfd->tbs[idx];
+ u16 hi_n_len = len << 4;
+
+ put_unaligned_le32(addr, &tb->lo);
+ if (sizeof(dma_addr_t) > sizeof(u32))
+ hi_n_len |= ((addr >> 16) >> 16) & 0xF;
+
+ tb->hi_n_len = cpu_to_le16(hi_n_len);
+
+ tfd->num_tbs = idx + 1;
+}
+
+static inline u8 iwl_tfd_get_num_tbs(struct iwl_tfd *tfd)
+{
+ return tfd->num_tbs & 0x1f;
+}
+
+static void iwlagn_unmap_tfd(struct iwl_trans *trans, struct iwl_cmd_meta *meta,
+ struct iwl_tfd *tfd, enum dma_data_direction dma_dir)
+{
+ int i;
+ int num_tbs;
+
+ /* Sanity check on number of chunks */
+ num_tbs = iwl_tfd_get_num_tbs(tfd);
+
+ if (num_tbs >= IWL_NUM_OF_TBS) {
+ IWL_ERR(trans, "Too many chunks: %i\n", num_tbs);
+ /* @todo issue fatal error, it is quite serious situation */
+ return;
+ }
+
+ /* Unmap tx_cmd */
+ if (num_tbs)
+ dma_unmap_single(bus(trans)->dev,
+ dma_unmap_addr(meta, mapping),
+ dma_unmap_len(meta, len),
+ DMA_BIDIRECTIONAL);
+
+ /* Unmap chunks, if any. */
+ for (i = 1; i < num_tbs; i++)
+ dma_unmap_single(bus(trans)->dev, iwl_tfd_tb_get_addr(tfd, i),
+ iwl_tfd_tb_get_len(tfd, i), dma_dir);
+}
+
+/**
+ * iwlagn_txq_free_tfd - Free all chunks referenced by TFD [txq->q.read_ptr]
+ * @trans - transport private data
+ * @txq - tx queue
+ * @index - the index of the TFD to be freed
+ *@dma_dir - the direction of the DMA mapping
+ *
+ * Does NOT advance any TFD circular buffer read/write indexes
+ * Does NOT free the TFD itself (which is within circular buffer)
+ */
+void iwlagn_txq_free_tfd(struct iwl_trans *trans, struct iwl_tx_queue *txq,
+ int index, enum dma_data_direction dma_dir)
+{
+ struct iwl_tfd *tfd_tmp = txq->tfds;
+
+ iwlagn_unmap_tfd(trans, &txq->meta[index], &tfd_tmp[index], dma_dir);
+
+ /* free SKB */
+ if (txq->skbs) {
+ struct sk_buff *skb;
+
+ skb = txq->skbs[index];
+
+ /* Can be called from irqs-disabled context
+ * If skb is not NULL, it means that the whole queue is being
+ * freed and that the queue is not empty - free the skb
+ */
+ if (skb) {
+ iwl_free_skb(priv(trans), skb);
+ txq->skbs[index] = NULL;
+ }
+ }
+}
+
+int iwlagn_txq_attach_buf_to_tfd(struct iwl_trans *trans,
+ struct iwl_tx_queue *txq,
+ dma_addr_t addr, u16 len,
+ u8 reset)
+{
+ struct iwl_queue *q;
+ struct iwl_tfd *tfd, *tfd_tmp;
+ u32 num_tbs;
+
+ q = &txq->q;
+ tfd_tmp = txq->tfds;
+ tfd = &tfd_tmp[q->write_ptr];
+
+ if (reset)
+ memset(tfd, 0, sizeof(*tfd));
+
+ num_tbs = iwl_tfd_get_num_tbs(tfd);
+
+ /* Each TFD can point to a maximum 20 Tx buffers */
+ if (num_tbs >= IWL_NUM_OF_TBS) {
+ IWL_ERR(trans, "Error can not send more than %d chunks\n",
+ IWL_NUM_OF_TBS);
+ return -EINVAL;
+ }
+
+ if (WARN_ON(addr & ~DMA_BIT_MASK(36)))
+ return -EINVAL;
+
+ if (unlikely(addr & ~IWL_TX_DMA_MASK))
+ IWL_ERR(trans, "Unaligned address = %llx\n",
+ (unsigned long long)addr);
+
+ iwl_tfd_set_tb(tfd, num_tbs, addr, len);
+
+ return 0;
+}
+
+/*************** 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.
+ *
+ ***************************************************/
+
+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;
+}
+
+/**
+ * iwl_queue_init - Initialize queue's high/low-water and read/write indexes
+ */
+int iwl_queue_init(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. */
+ if (WARN_ON(!is_power_of_2(count)))
+ return -EINVAL;
+
+ /* slots_num must be power-of-two size, otherwise
+ * get_cmd_index is broken. */
+ if (WARN_ON(!is_power_of_2(slots_num)))
+ return -EINVAL;
+
+ 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;
+}
+
+static void iwlagn_txq_inval_byte_cnt_tbl(struct iwl_trans *trans,
+ struct iwl_tx_queue *txq)
+{
+ struct iwl_trans_pcie *trans_pcie =
+ IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwlagn_scd_bc_tbl *scd_bc_tbl = trans_pcie->scd_bc_tbls.addr;
+ int txq_id = txq->q.id;
+ int read_ptr = txq->q.read_ptr;
+ u8 sta_id = 0;
+ __le16 bc_ent;
+
+ WARN_ON(read_ptr >= TFD_QUEUE_SIZE_MAX);
+
+ if (txq_id != trans->shrd->cmd_queue)
+ sta_id = txq->cmd[read_ptr]->cmd.tx.sta_id;
+
+ bc_ent = cpu_to_le16(1 | (sta_id << 12));
+ scd_bc_tbl[txq_id].tfd_offset[read_ptr] = bc_ent;
+
+ if (read_ptr < TFD_QUEUE_SIZE_BC_DUP)
+ scd_bc_tbl[txq_id].
+ tfd_offset[TFD_QUEUE_SIZE_MAX + read_ptr] = bc_ent;
+}
+
+static int iwlagn_tx_queue_set_q2ratid(struct iwl_trans *trans, u16 ra_tid,
+ u16 txq_id)
+{
+ u32 tbl_dw_addr;
+ u32 tbl_dw;
+ u16 scd_q2ratid;
+
+ struct iwl_trans_pcie *trans_pcie =
+ IWL_TRANS_GET_PCIE_TRANS(trans);
+
+ scd_q2ratid = ra_tid & SCD_QUEUE_RA_TID_MAP_RATID_MSK;
+
+ tbl_dw_addr = trans_pcie->scd_base_addr +
+ SCD_TRANS_TBL_OFFSET_QUEUE(txq_id);
+
+ tbl_dw = iwl_read_targ_mem(bus(trans), tbl_dw_addr);
+
+ if (txq_id & 0x1)
+ tbl_dw = (scd_q2ratid << 16) | (tbl_dw & 0x0000FFFF);
+ else
+ tbl_dw = scd_q2ratid | (tbl_dw & 0xFFFF0000);
+
+ iwl_write_targ_mem(bus(trans), tbl_dw_addr, tbl_dw);
+
+ return 0;
+}
+
+static void iwlagn_tx_queue_stop_scheduler(struct iwl_trans *trans, 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_write_prph(bus(trans),
+ SCD_QUEUE_STATUS_BITS(txq_id),
+ (0 << SCD_QUEUE_STTS_REG_POS_ACTIVE)|
+ (1 << SCD_QUEUE_STTS_REG_POS_SCD_ACT_EN));
+}
+
+void iwl_trans_set_wr_ptrs(struct iwl_trans *trans,
+ int txq_id, u32 index)
+{
+ iwl_write_direct32(bus(trans), HBUS_TARG_WRPTR,
+ (index & 0xff) | (txq_id << 8));
+ iwl_write_prph(bus(trans), SCD_QUEUE_RDPTR(txq_id), index);
+}
+
+void iwl_trans_tx_queue_set_status(struct iwl_trans *trans,
+ struct iwl_tx_queue *txq,
+ int tx_fifo_id, int scd_retry)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ int txq_id = txq->q.id;
+ int active =
+ test_bit(txq_id, &trans_pcie->txq_ctx_active_msk) ? 1 : 0;
+
+ iwl_write_prph(bus(trans), SCD_QUEUE_STATUS_BITS(txq_id),
+ (active << SCD_QUEUE_STTS_REG_POS_ACTIVE) |
+ (tx_fifo_id << SCD_QUEUE_STTS_REG_POS_TXF) |
+ (1 << SCD_QUEUE_STTS_REG_POS_WSL) |
+ SCD_QUEUE_STTS_REG_MSK);
+
+ txq->sched_retry = scd_retry;
+
+ IWL_DEBUG_INFO(trans, "%s %s Queue %d on FIFO %d\n",
+ active ? "Activate" : "Deactivate",
+ scd_retry ? "BA" : "AC/CMD", txq_id, tx_fifo_id);
+}
+
+static inline int get_fifo_from_tid(struct iwl_trans_pcie *trans_pcie,
+ u8 ctx, u16 tid)
+{
+ const u8 *ac_to_fifo = trans_pcie->ac_to_fifo[ctx];
+ if (likely(tid < ARRAY_SIZE(tid_to_ac)))
+ return ac_to_fifo[tid_to_ac[tid]];
+
+ /* no support for TIDs 8-15 yet */
+ return -EINVAL;
+}
+
+void iwl_trans_pcie_tx_agg_setup(struct iwl_trans *trans,
+ enum iwl_rxon_context_id ctx, int sta_id,
+ int tid, int frame_limit)
+{
+ int tx_fifo, txq_id, ssn_idx;
+ u16 ra_tid;
+ unsigned long flags;
+ struct iwl_tid_data *tid_data;
+
+ struct iwl_trans_pcie *trans_pcie =
+ IWL_TRANS_GET_PCIE_TRANS(trans);
+
+ if (WARN_ON(sta_id == IWL_INVALID_STATION))
+ return;
+ if (WARN_ON(tid >= IWL_MAX_TID_COUNT))
+ return;
+
+ tx_fifo = get_fifo_from_tid(trans_pcie, ctx, tid);
+ if (WARN_ON(tx_fifo < 0)) {
+ IWL_ERR(trans, "txq_agg_setup, bad fifo: %d\n", tx_fifo);
+ return;
+ }
+
+ spin_lock_irqsave(&trans->shrd->sta_lock, flags);
+ tid_data = &trans->shrd->tid_data[sta_id][tid];
+ ssn_idx = SEQ_TO_SN(tid_data->seq_number);
+ txq_id = tid_data->agg.txq_id;
+ spin_unlock_irqrestore(&trans->shrd->sta_lock, flags);
+
+ ra_tid = BUILD_RAxTID(sta_id, tid);
+
+ spin_lock_irqsave(&trans->shrd->lock, flags);
+
+ /* Stop this Tx queue before configuring it */
+ iwlagn_tx_queue_stop_scheduler(trans, txq_id);
+
+ /* Map receiver-address / traffic-ID to this queue */
+ iwlagn_tx_queue_set_q2ratid(trans, ra_tid, txq_id);
+
+ /* Set this queue as a chain-building queue */
+ iwl_set_bits_prph(bus(trans), SCD_QUEUECHAIN_SEL, (1<<txq_id));
+
+ /* enable aggregations for the queue */
+ iwl_set_bits_prph(bus(trans), SCD_AGGR_SEL, (1<<txq_id));
+
+ /* Place first TFD at index corresponding to start sequence number.
+ * Assumes that ssn_idx is valid (!= 0xFFF) */
+ trans_pcie->txq[txq_id].q.read_ptr = (ssn_idx & 0xff);
+ trans_pcie->txq[txq_id].q.write_ptr = (ssn_idx & 0xff);
+ iwl_trans_set_wr_ptrs(trans, txq_id, ssn_idx);
+
+ /* Set up Tx window size and frame limit for this queue */
+ iwl_write_targ_mem(bus(trans), trans_pcie->scd_base_addr +
+ SCD_CONTEXT_QUEUE_OFFSET(txq_id) +
+ sizeof(u32),
+ ((frame_limit <<
+ SCD_QUEUE_CTX_REG2_WIN_SIZE_POS) &
+ SCD_QUEUE_CTX_REG2_WIN_SIZE_MSK) |
+ ((frame_limit <<
+ SCD_QUEUE_CTX_REG2_FRAME_LIMIT_POS) &
+ SCD_QUEUE_CTX_REG2_FRAME_LIMIT_MSK));
+
+ iwl_set_bits_prph(bus(trans), SCD_INTERRUPT_MASK, (1 << txq_id));
+
+ /* Set up Status area in SRAM, map to Tx DMA/FIFO, activate the queue */
+ iwl_trans_tx_queue_set_status(trans, &trans_pcie->txq[txq_id],
+ tx_fifo, 1);
+
+ trans_pcie->txq[txq_id].sta_id = sta_id;
+ trans_pcie->txq[txq_id].tid = tid;
+
+ spin_unlock_irqrestore(&trans->shrd->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 iwlagn_txq_ctx_activate_free(struct iwl_trans *trans)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ int txq_id;
+
+ for (txq_id = 0; txq_id < hw_params(trans).max_txq_num; txq_id++)
+ if (!test_and_set_bit(txq_id,
+ &trans_pcie->txq_ctx_active_msk))
+ return txq_id;
+ return -1;
+}
+
+int iwl_trans_pcie_tx_agg_alloc(struct iwl_trans *trans,
+ enum iwl_rxon_context_id ctx, int sta_id,
+ int tid, u16 *ssn)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwl_tid_data *tid_data;
+ unsigned long flags;
+ u16 txq_id;
+
+ txq_id = iwlagn_txq_ctx_activate_free(trans);
+ if (txq_id == -1) {
+ IWL_ERR(trans, "No free aggregation queue available\n");
+ return -ENXIO;
+ }
+
+ spin_lock_irqsave(&trans->shrd->sta_lock, flags);
+ tid_data = &trans->shrd->tid_data[sta_id][tid];
+ *ssn = SEQ_TO_SN(tid_data->seq_number);
+ tid_data->agg.txq_id = txq_id;
+ iwl_set_swq_id(&trans_pcie->txq[txq_id], get_ac_from_tid(tid), txq_id);
+
+ tid_data = &trans->shrd->tid_data[sta_id][tid];
+ if (tid_data->tfds_in_queue == 0) {
+ IWL_DEBUG_HT(trans, "HW queue is empty\n");
+ tid_data->agg.state = IWL_AGG_ON;
+ iwl_start_tx_ba_trans_ready(priv(trans), ctx, sta_id, tid);
+ } else {
+ IWL_DEBUG_HT(trans, "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(&trans->shrd->sta_lock, flags);
+
+ return 0;
+}
+
+void iwl_trans_pcie_txq_agg_disable(struct iwl_trans *trans, int txq_id)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ iwlagn_tx_queue_stop_scheduler(trans, txq_id);
+
+ iwl_clear_bits_prph(bus(trans), SCD_AGGR_SEL, (1 << txq_id));
+
+ trans_pcie->txq[txq_id].q.read_ptr = 0;
+ trans_pcie->txq[txq_id].q.write_ptr = 0;
+ /* supposes that ssn_idx is valid (!= 0xFFF) */
+ iwl_trans_set_wr_ptrs(trans, txq_id, 0);
+
+ iwl_clear_bits_prph(bus(trans), SCD_INTERRUPT_MASK, (1 << txq_id));
+ iwl_txq_ctx_deactivate(trans_pcie, txq_id);
+ iwl_trans_tx_queue_set_status(trans, &trans_pcie->txq[txq_id], 0, 0);
+}
+
+int iwl_trans_pcie_tx_agg_disable(struct iwl_trans *trans,
+ enum iwl_rxon_context_id ctx, int sta_id,
+ int tid)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ unsigned long flags;
+ int read_ptr, write_ptr;
+ struct iwl_tid_data *tid_data;
+ int txq_id;
+
+ spin_lock_irqsave(&trans->shrd->sta_lock, flags);
+
+ tid_data = &trans->shrd->tid_data[sta_id][tid];
+ txq_id = tid_data->agg.txq_id;
+
+ if ((IWLAGN_FIRST_AMPDU_QUEUE > txq_id) ||
+ (IWLAGN_FIRST_AMPDU_QUEUE +
+ hw_params(trans).num_ampdu_queues <= txq_id)) {
+ IWL_ERR(trans,
+ "queue number out of range: %d, must be %d to %d\n",
+ txq_id, IWLAGN_FIRST_AMPDU_QUEUE,
+ IWLAGN_FIRST_AMPDU_QUEUE +
+ hw_params(trans).num_ampdu_queues - 1);
+ spin_unlock_irqrestore(&trans->shrd->sta_lock, flags);
+ return -EINVAL;
+ }
+
+ switch (trans->shrd->tid_data[sta_id][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(trans, "AGG stop before setup done\n");
+ goto turn_off;
+ case IWL_AGG_ON:
+ break;
+ default:
+ IWL_WARN(trans, "Stopping AGG while state not ON"
+ "or starting\n");
+ }
+
+ write_ptr = trans_pcie->txq[txq_id].q.write_ptr;
+ read_ptr = trans_pcie->txq[txq_id].q.read_ptr;
+
+ /* The queue is not empty */
+ if (write_ptr != read_ptr) {
+ IWL_DEBUG_HT(trans, "Stopping a non empty AGG HW QUEUE\n");
+ trans->shrd->tid_data[sta_id][tid].agg.state =
+ IWL_EMPTYING_HW_QUEUE_DELBA;
+ spin_unlock_irqrestore(&trans->shrd->sta_lock, flags);
+ return 0;
+ }
+
+ IWL_DEBUG_HT(trans, "HW queue is empty\n");
+turn_off:
+ trans->shrd->tid_data[sta_id][tid].agg.state = IWL_AGG_OFF;
+
+ /* do not restore/save irqs */
+ spin_unlock(&trans->shrd->sta_lock);
+ spin_lock(&trans->shrd->lock);
+
+ iwl_trans_pcie_txq_agg_disable(trans, txq_id);
+
+ spin_unlock_irqrestore(&trans->shrd->lock, flags);
+
+ iwl_stop_tx_ba_trans_ready(priv(trans), ctx, sta_id, tid);
+
+ return 0;
+}
+
+/*************** 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.
+ */
+static int iwl_enqueue_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwl_tx_queue *txq = &trans_pcie->txq[trans->shrd->cmd_queue];
+ struct iwl_queue *q = &txq->q;
+ struct iwl_device_cmd *out_cmd;
+ struct iwl_cmd_meta *out_meta;
+ dma_addr_t phys_addr;
+ unsigned long flags;
+ u32 idx;
+ u16 copy_size, cmd_size;
+ bool is_ct_kill = false;
+ bool had_nocopy = false;
+ int i;
+ u8 *cmd_dest;
+#ifdef CONFIG_IWLWIFI_DEVICE_TRACING
+ const void *trace_bufs[IWL_MAX_CMD_TFDS + 1] = {};
+ int trace_lens[IWL_MAX_CMD_TFDS + 1] = {};
+ int trace_idx;
+#endif
+
+ if (test_bit(STATUS_FW_ERROR, &trans->shrd->status)) {
+ IWL_WARN(trans, "fw recovery, no hcmd send\n");
+ return -EIO;
+ }
+
+ if ((trans->shrd->ucode_owner == IWL_OWNERSHIP_TM) &&
+ !(cmd->flags & CMD_ON_DEMAND)) {
+ IWL_DEBUG_HC(trans, "tm own the uCode, no regular hcmd send\n");
+ return -EIO;
+ }
+
+ copy_size = sizeof(out_cmd->hdr);
+ cmd_size = sizeof(out_cmd->hdr);
+
+ /* need one for the header if the first is NOCOPY */
+ BUILD_BUG_ON(IWL_MAX_CMD_TFDS > IWL_NUM_OF_TBS - 1);
+
+ for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
+ if (!cmd->len[i])
+ continue;
+ if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY) {
+ had_nocopy = true;
+ } else {
+ /* NOCOPY must not be followed by normal! */
+ if (WARN_ON(had_nocopy))
+ return -EINVAL;
+ copy_size += cmd->len[i];
+ }
+ cmd_size += cmd->len[i];
+ }
+
+ /*
+ * If any of the command structures end up being larger than
+ * the TFD_MAX_PAYLOAD_SIZE and they aren't dynamically
+ * allocated into separate TFDs, then we will need to
+ * increase the size of the buffers.
+ */
+ if (WARN_ON(copy_size > TFD_MAX_PAYLOAD_SIZE))
+ return -EINVAL;
+
+ if (iwl_is_rfkill(trans->shrd) || iwl_is_ctkill(trans->shrd)) {
+ IWL_WARN(trans, "Not sending command - %s KILL\n",
+ iwl_is_rfkill(trans->shrd) ? "RF" : "CT");
+ return -EIO;
+ }
+
+ spin_lock_irqsave(&trans->hcmd_lock, flags);
+
+ if (iwl_queue_space(q) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
+ spin_unlock_irqrestore(&trans->hcmd_lock, flags);
+
+ IWL_ERR(trans, "No space in command queue\n");
+ is_ct_kill = iwl_check_for_ct_kill(priv(trans));
+ if (!is_ct_kill) {
+ IWL_ERR(trans, "Restarting adapter queue is full\n");
+ iwlagn_fw_error(priv(trans), false);
+ }
+ return -ENOSPC;
+ }
+
+ idx = get_cmd_index(q, q->write_ptr);
+ out_cmd = txq->cmd[idx];
+ out_meta = &txq->meta[idx];
+
+ memset(out_meta, 0, sizeof(*out_meta)); /* re-initialize to NULL */
+ if (cmd->flags & CMD_WANT_SKB)
+ out_meta->source = cmd;
+ if (cmd->flags & CMD_ASYNC)
+ out_meta->callback = cmd->callback;
+
+ /* set up the header */
+
+ out_cmd->hdr.cmd = cmd->id;
+ out_cmd->hdr.flags = 0;
+ out_cmd->hdr.sequence =
+ cpu_to_le16(QUEUE_TO_SEQ(trans->shrd->cmd_queue) |
+ INDEX_TO_SEQ(q->write_ptr));
+
+ /* and copy the data that needs to be copied */
+
+ cmd_dest = &out_cmd->cmd.payload[0];
+ for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
+ if (!cmd->len[i])
+ continue;
+ if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY)
+ break;
+ memcpy(cmd_dest, cmd->data[i], cmd->len[i]);
+ cmd_dest += cmd->len[i];
+ }
+
+ IWL_DEBUG_HC(trans, "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), cmd_size,
+ q->write_ptr, idx, trans->shrd->cmd_queue);
+
+ phys_addr = dma_map_single(bus(trans)->dev, &out_cmd->hdr, copy_size,
+ DMA_BIDIRECTIONAL);
+ if (unlikely(dma_mapping_error(bus(trans)->dev, phys_addr))) {
+ idx = -ENOMEM;
+ goto out;
+ }
+
+ dma_unmap_addr_set(out_meta, mapping, phys_addr);
+ dma_unmap_len_set(out_meta, len, copy_size);
+
+ iwlagn_txq_attach_buf_to_tfd(trans, txq,
+ phys_addr, copy_size, 1);
+#ifdef CONFIG_IWLWIFI_DEVICE_TRACING
+ trace_bufs[0] = &out_cmd->hdr;
+ trace_lens[0] = copy_size;
+ trace_idx = 1;
+#endif
+
+ for (i = 0; i < IWL_MAX_CMD_TFDS; i++) {
+ if (!cmd->len[i])
+ continue;
+ if (!(cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY))
+ continue;
+ phys_addr = dma_map_single(bus(trans)->dev,
+ (void *)cmd->data[i],
+ cmd->len[i], DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(bus(trans)->dev, phys_addr)) {
+ iwlagn_unmap_tfd(trans, out_meta,
+ &txq->tfds[q->write_ptr],
+ DMA_BIDIRECTIONAL);
+ idx = -ENOMEM;
+ goto out;
+ }
+
+ iwlagn_txq_attach_buf_to_tfd(trans, txq, phys_addr,
+ cmd->len[i], 0);
+#ifdef CONFIG_IWLWIFI_DEVICE_TRACING
+ trace_bufs[trace_idx] = cmd->data[i];
+ trace_lens[trace_idx] = cmd->len[i];
+ trace_idx++;
+#endif
+ }
+
+ out_meta->flags = cmd->flags;
+
+ txq->need_update = 1;
+
+ /* check that tracing gets all possible blocks */
+ BUILD_BUG_ON(IWL_MAX_CMD_TFDS + 1 != 3);
+#ifdef CONFIG_IWLWIFI_DEVICE_TRACING
+ trace_iwlwifi_dev_hcmd(priv(trans), cmd->flags,
+ trace_bufs[0], trace_lens[0],
+ trace_bufs[1], trace_lens[1],
+ trace_bufs[2], trace_lens[2]);
+#endif
+
+ /* Increment and update queue's write index */
+ q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
+ iwl_txq_update_write_ptr(trans, txq);
+
+ out:
+ spin_unlock_irqrestore(&trans->hcmd_lock, flags);
+ return idx;
+}
+
+/**
+ * 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_trans *trans, int txq_id,
+ int idx)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwl_tx_queue *txq = &trans_pcie->txq[txq_id];
+ struct iwl_queue *q = &txq->q;
+ int nfreed = 0;
+
+ if ((idx >= q->n_bd) || (iwl_queue_used(q, idx) == 0)) {
+ IWL_ERR(trans, "%s: Read index for DMA queue txq id (%d), "
+ "index %d is out of range [0-%d] %d %d.\n", __func__,
+ txq_id, idx, q->n_bd, q->write_ptr, q->read_ptr);
+ return;
+ }
+
+ for (idx = iwl_queue_inc_wrap(idx, q->n_bd); q->read_ptr != idx;
+ q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) {
+
+ if (nfreed++ > 0) {
+ IWL_ERR(trans, "HCMD skipped: index (%d) %d %d\n", idx,
+ q->write_ptr, q->read_ptr);
+ iwlagn_fw_error(priv(trans), false);
+ }
+
+ }
+}
+
+/**
+ * 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_trans *trans, struct iwl_rx_mem_buffer *rxb)
+{
+ struct iwl_rx_packet *pkt = rxb_addr(rxb);
+ u16 sequence = le16_to_cpu(pkt->hdr.sequence);
+ int txq_id = SEQ_TO_QUEUE(sequence);
+ int index = SEQ_TO_INDEX(sequence);
+ int cmd_index;
+ struct iwl_device_cmd *cmd;
+ struct iwl_cmd_meta *meta;
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwl_tx_queue *txq = &trans_pcie->txq[trans->shrd->cmd_queue];
+ unsigned long flags;
+
+ /* 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 (WARN(txq_id != trans->shrd->cmd_queue,
+ "wrong command queue %d (should be %d), sequence 0x%X readp=%d writep=%d\n",
+ txq_id, trans->shrd->cmd_queue, sequence,
+ trans_pcie->txq[trans->shrd->cmd_queue].q.read_ptr,
+ trans_pcie->txq[trans->shrd->cmd_queue].q.write_ptr)) {
+ iwl_print_hex_error(trans, pkt, 32);
+ return;
+ }
+
+ cmd_index = get_cmd_index(&txq->q, index);
+ cmd = txq->cmd[cmd_index];
+ meta = &txq->meta[cmd_index];
+
+ iwlagn_unmap_tfd(trans, meta, &txq->tfds[index],
+ DMA_BIDIRECTIONAL);
+
+ /* Input error checking is done when commands are added to queue. */
+ if (meta->flags & CMD_WANT_SKB) {
+ meta->source->reply_page = (unsigned long)rxb_addr(rxb);
+ rxb->page = NULL;
+ } else if (meta->callback)
+ meta->callback(trans->shrd, cmd, pkt);
+
+ spin_lock_irqsave(&trans->hcmd_lock, flags);
+
+ iwl_hcmd_queue_reclaim(trans, txq_id, index);
+
+ if (!(meta->flags & CMD_ASYNC)) {
+ clear_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status);
+ IWL_DEBUG_INFO(trans, "Clearing HCMD_ACTIVE for command %s\n",
+ get_cmd_string(cmd->hdr.cmd));
+ wake_up_interruptible(&trans->shrd->wait_command_queue);
+ }
+
+ meta->flags = 0;
+
+ spin_unlock_irqrestore(&trans->hcmd_lock, flags);
+}
+
+#define HOST_COMPLETE_TIMEOUT (2 * HZ)
+
+static void iwl_generic_cmd_callback(struct iwl_shared *shrd,
+ struct iwl_device_cmd *cmd,
+ struct iwl_rx_packet *pkt)
+{
+ if (pkt->hdr.flags & IWL_CMD_FAILED_MSK) {
+ IWL_ERR(shrd->trans, "Bad return from %s (0x%08X)\n",
+ get_cmd_string(cmd->hdr.cmd), pkt->hdr.flags);
+ return;
+ }
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+ switch (cmd->hdr.cmd) {
+ case REPLY_TX_LINK_QUALITY_CMD:
+ case SENSITIVITY_CMD:
+ IWL_DEBUG_HC_DUMP(shrd->trans, "back from %s (0x%08X)\n",
+ get_cmd_string(cmd->hdr.cmd), pkt->hdr.flags);
+ break;
+ default:
+ IWL_DEBUG_HC(shrd->trans, "back from %s (0x%08X)\n",
+ get_cmd_string(cmd->hdr.cmd), pkt->hdr.flags);
+ }
+#endif
+}
+
+static int iwl_send_cmd_async(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
+{
+ int ret;
+
+ /* An asynchronous command can not expect an SKB to be set. */
+ if (WARN_ON(cmd->flags & CMD_WANT_SKB))
+ return -EINVAL;
+
+ /* Assign a generic callback if one is not provided */
+ if (!cmd->callback)
+ cmd->callback = iwl_generic_cmd_callback;
+
+ if (test_bit(STATUS_EXIT_PENDING, &trans->shrd->status))
+ return -EBUSY;
+
+ ret = iwl_enqueue_hcmd(trans, cmd);
+ if (ret < 0) {
+ IWL_ERR(trans, "Error sending %s: enqueue_hcmd failed: %d\n",
+ get_cmd_string(cmd->id), ret);
+ return ret;
+ }
+ return 0;
+}
+
+static int iwl_send_cmd_sync(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ int cmd_idx;
+ int ret;
+
+ lockdep_assert_held(&trans->shrd->mutex);
+
+ /* A synchronous command can not have a callback set. */
+ if (WARN_ON(cmd->callback))
+ return -EINVAL;
+
+ IWL_DEBUG_INFO(trans, "Attempting to send sync command %s\n",
+ get_cmd_string(cmd->id));
+
+ set_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status);
+ IWL_DEBUG_INFO(trans, "Setting HCMD_ACTIVE for command %s\n",
+ get_cmd_string(cmd->id));
+
+ cmd_idx = iwl_enqueue_hcmd(trans, cmd);
+ if (cmd_idx < 0) {
+ ret = cmd_idx;
+ clear_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status);
+ IWL_ERR(trans, "Error sending %s: enqueue_hcmd failed: %d\n",
+ get_cmd_string(cmd->id), ret);
+ return ret;
+ }
+
+ ret = wait_event_interruptible_timeout(trans->shrd->wait_command_queue,
+ !test_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status),
+ HOST_COMPLETE_TIMEOUT);
+ if (!ret) {
+ if (test_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status)) {
+ IWL_ERR(trans,
+ "Error sending %s: time out after %dms.\n",
+ get_cmd_string(cmd->id),
+ jiffies_to_msecs(HOST_COMPLETE_TIMEOUT));
+
+ clear_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status);
+ IWL_DEBUG_INFO(trans, "Clearing HCMD_ACTIVE for command"
+ "%s\n", get_cmd_string(cmd->id));
+ ret = -ETIMEDOUT;
+ goto cancel;
+ }
+ }
+
+ if (test_bit(STATUS_RF_KILL_HW, &trans->shrd->status)) {
+ IWL_ERR(trans, "Command %s aborted: RF KILL Switch\n",
+ get_cmd_string(cmd->id));
+ ret = -ECANCELED;
+ goto fail;
+ }
+ if (test_bit(STATUS_FW_ERROR, &trans->shrd->status)) {
+ IWL_ERR(trans, "Command %s failed: FW Error\n",
+ get_cmd_string(cmd->id));
+ ret = -EIO;
+ goto fail;
+ }
+ if ((cmd->flags & CMD_WANT_SKB) && !cmd->reply_page) {
+ IWL_ERR(trans, "Error: Response NULL in '%s'\n",
+ get_cmd_string(cmd->id));
+ ret = -EIO;
+ goto cancel;
+ }
+
+ return 0;
+
+cancel:
+ if (cmd->flags & CMD_WANT_SKB) {
+ /*
+ * Cancel the CMD_WANT_SKB flag for the cmd in the
+ * TX cmd queue. Otherwise in case the cmd comes
+ * in later, it will possibly set an invalid
+ * address (cmd->meta.source).
+ */
+ trans_pcie->txq[trans->shrd->cmd_queue].meta[cmd_idx].flags &=
+ ~CMD_WANT_SKB;
+ }
+fail:
+ if (cmd->reply_page) {
+ iwl_free_pages(trans->shrd, cmd->reply_page);
+ cmd->reply_page = 0;
+ }
+
+ return ret;
+}
+
+int iwl_trans_pcie_send_cmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
+{
+ if (cmd->flags & CMD_ASYNC)
+ return iwl_send_cmd_async(trans, cmd);
+
+ return iwl_send_cmd_sync(trans, cmd);
+}
+
+int iwl_trans_pcie_send_cmd_pdu(struct iwl_trans *trans, u8 id, u32 flags,
+ u16 len, const void *data)
+{
+ struct iwl_host_cmd cmd = {
+ .id = id,
+ .len = { len, },
+ .data = { data, },
+ .flags = flags,
+ };
+
+ return iwl_trans_pcie_send_cmd(trans, &cmd);
+}
+
+/* Frees buffers until index _not_ inclusive */
+int iwl_tx_queue_reclaim(struct iwl_trans *trans, int txq_id, int index,
+ struct sk_buff_head *skbs)
+{
+ struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+ struct iwl_tx_queue *txq = &trans_pcie->txq[txq_id];
+ struct iwl_queue *q = &txq->q;
+ int last_to_free;
+ int freed = 0;
+
+ /* This function is not meant to release cmd queue*/
+ if (WARN_ON(txq_id == trans->shrd->cmd_queue))
+ return 0;
+
+ /*Since we free until index _not_ inclusive, the one before index is
+ * the last we will free. This one must be used */
+ last_to_free = iwl_queue_dec_wrap(index, q->n_bd);
+
+ if ((index >= q->n_bd) ||
+ (iwl_queue_used(q, last_to_free) == 0)) {
+ IWL_ERR(trans, "%s: Read index for DMA queue txq id (%d), "
+ "last_to_free %d is out of range [0-%d] %d %d.\n",
+ __func__, txq_id, last_to_free, q->n_bd,
+ q->write_ptr, q->read_ptr);
+ return 0;
+ }
+
+ IWL_DEBUG_TX_REPLY(trans, "reclaim: [%d, %d, %d]\n", txq_id,
+ q->read_ptr, index);
+
+ if (WARN_ON(!skb_queue_empty(skbs)))
+ return 0;
+
+ for (;
+ q->read_ptr != index;
+ q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd)) {
+
+ if (WARN_ON_ONCE(txq->skbs[txq->q.read_ptr] == NULL))
+ continue;
+
+ __skb_queue_tail(skbs, txq->skbs[txq->q.read_ptr]);
+
+ txq->skbs[txq->q.read_ptr] = NULL;
+
+ iwlagn_txq_inval_byte_cnt_tbl(trans, txq);
+
+ iwlagn_txq_free_tfd(trans, txq, txq->q.read_ptr, DMA_TO_DEVICE);
+ freed++;
+ }
+ return freed;
+}