path: root/drivers/net/wireless/iwlwifi/pcie/trans.c

/******************************************************************************
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2007 - 2012 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
 *
 * BSD LICENSE
 *
 * Copyright(c) 2005 - 2012 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *****************************************************************************/
#include <linux/pci.h>
#include <linux/pci-aspm.h>
#include <linux/interrupt.h>
#include <linux/debugfs.h>
#include <linux/sched.h>
#include <linux/bitops.h>
#include <linux/gfp.h>

#include "iwl-drv.h"
#include "iwl-trans.h"
#include "iwl-csr.h"
#include "iwl-prph.h"
#include "iwl-agn-hw.h"
#include "internal.h"
/* FIXME: need to abstract out TX command (once we know what it looks like) */
#include "dvm/commands.h"

#define SCD_QUEUECHAIN_SEL_ALL(trans, trans_pcie)	\
	(((1<<trans->cfg->base_params->num_of_queues) - 1) &\
	(~(1<<(trans_pcie)->cmd_queue)))

static int iwl_trans_rx_alloc(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
	struct device *dev = trans->dev;

	memset(&trans_pcie->rxq, 0, sizeof(trans_pcie->rxq));

	spin_lock_init(&rxq->lock);

	if (WARN_ON(rxq->bd || rxq->rb_stts))
		return -EINVAL;

	/* Allocate the circular buffer of Read Buffer Descriptors (RBDs) */
	rxq->bd = dma_zalloc_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE,
				      &rxq->bd_dma, GFP_KERNEL);
	if (!rxq->bd)
		goto err_bd;

	/*Allocate the driver's pointer to receive buffer status */
	rxq->rb_stts = dma_zalloc_coherent(dev, sizeof(*rxq->rb_stts),
					   &rxq->rb_stts_dma, GFP_KERNEL);
	if (!rxq->rb_stts)
		goto err_rb_stts;

	return 0;

err_rb_stts:
	dma_free_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE,
			  rxq->bd, rxq->bd_dma);
	memset(&rxq->bd_dma, 0, sizeof(rxq->bd_dma));
	rxq->bd = NULL;
err_bd:
	return -ENOMEM;
}

static void iwl_trans_rxq_free_rx_bufs(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
	int i;

	/* Fill the rx_used queue with _all_ of the Rx buffers */
	for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
		/* In the reset function, these buffers may have been allocated
		 * to an SKB, so we need to unmap and free potential storage */
		if (rxq->pool[i].page != NULL) {
			dma_unmap_page(trans->dev, rxq->pool[i].page_dma,
				       PAGE_SIZE << trans_pcie->rx_page_order,
				       DMA_FROM_DEVICE);
			__free_pages(rxq->pool[i].page,
				     trans_pcie->rx_page_order);
			rxq->pool[i].page = NULL;
		}
		list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
	}
}

static void iwl_trans_rx_hw_init(struct iwl_trans *trans,
				 struct iwl_rx_queue *rxq)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	u32 rb_size;
	const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
	u32 rb_timeout = RX_RB_TIMEOUT; /* FIXME: RX_RB_TIMEOUT for all devices? */

	if (trans_pcie->rx_buf_size_8k)
		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
	else
		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;

	/* Stop Rx DMA */
	iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);

	/* Reset driver's Rx queue write index */
	iwl_write_direct32(trans, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);

	/* Tell device where to find RBD circular buffer in DRAM */
	iwl_write_direct32(trans, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
			   (u32)(rxq->bd_dma >> 8));

	/* Tell device where in DRAM to update its Rx status */
	iwl_write_direct32(trans, FH_RSCSR_CHNL0_STTS_WPTR_REG,
			   rxq->rb_stts_dma >> 4);

	/* Enable Rx DMA
	 * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in
	 *      the credit mechanism in 5000 HW RX FIFO
	 * Direct rx interrupts to hosts
	 * Rx buffer size 4 or 8k
	 * RB timeout 0x10
	 * 256 RBDs
	 */
	iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG,
			   FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
			   FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY |
			   FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
			   rb_size|
			   (rb_timeout << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS)|
			   (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));

	/* Set interrupt coalescing timer to default (2048 usecs) */
	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
}

static int iwl_rx_init(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_rx_queue *rxq = &trans_pcie->rxq;

	int i, err;
	unsigned long flags;

	if (!rxq->bd) {
		err = iwl_trans_rx_alloc(trans);
		if (err)
			return err;
	}

	spin_lock_irqsave(&rxq->lock, flags);
	INIT_LIST_HEAD(&rxq->rx_free);
	INIT_LIST_HEAD(&rxq->rx_used);

	iwl_trans_rxq_free_rx_bufs(trans);

	for (i = 0; i < RX_QUEUE_SIZE; i++)
		rxq->queue[i] = NULL;

	/* Set us so that we have processed and used all buffers, but have
	 * not restocked the Rx queue with fresh buffers */
	rxq->read = rxq->write = 0;
	rxq->write_actual = 0;
	rxq->free_count = 0;
	spin_unlock_irqrestore(&rxq->lock, flags);

	iwlagn_rx_replenish(trans);

	iwl_trans_rx_hw_init(trans, rxq);

	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
	rxq->need_update = 1;
	iwl_rx_queue_update_write_ptr(trans, rxq);
	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	return 0;
}

static void iwl_trans_pcie_rx_free(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
	unsigned long flags;

	/*if rxq->bd is NULL, it means that nothing has been allocated,
	 * exit now */
	if (!rxq->bd) {
		IWL_DEBUG_INFO(trans, "Free NULL rx context\n");
		return;
	}

	spin_lock_irqsave(&rxq->lock, flags);
	iwl_trans_rxq_free_rx_bufs(trans);
	spin_unlock_irqrestore(&rxq->lock, flags);

	dma_free_coherent(trans->dev, sizeof(__le32) * RX_QUEUE_SIZE,
			  rxq->bd, rxq->bd_dma);
	memset(&rxq->bd_dma, 0, sizeof(rxq->bd_dma));
	rxq->bd = NULL;

	if (rxq->rb_stts)
		dma_free_coherent(trans->dev,
				  sizeof(struct iwl_rb_status),
				  rxq->rb_stts, rxq->rb_stts_dma);
	else
		IWL_DEBUG_INFO(trans, "Free rxq->rb_stts which is NULL\n");
	memset(&rxq->rb_stts_dma, 0, sizeof(rxq->rb_stts_dma));
	rxq->rb_stts = NULL;
}

static int iwl_trans_rx_stop(struct iwl_trans *trans)
{

	/* stop Rx DMA */
	iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
	return iwl_poll_direct_bit(trans, FH_MEM_RSSR_RX_STATUS_REG,
				   FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000);
}

static int iwlagn_alloc_dma_ptr(struct iwl_trans *trans,
				struct iwl_dma_ptr *ptr, size_t size)
{
	if (WARN_ON(ptr->addr))
		return -EINVAL;

	ptr->addr = dma_alloc_coherent(trans->dev, size,
				       &ptr->dma, GFP_KERNEL);
	if (!ptr->addr)
		return -ENOMEM;
	ptr->size = size;
	return 0;
}

static void iwlagn_free_dma_ptr(struct iwl_trans *trans,
				struct iwl_dma_ptr *ptr)
{
	if (unlikely(!ptr->addr))
		return;

	dma_free_coherent(trans->dev, ptr->size, ptr->addr, ptr->dma);
	memset(ptr, 0, sizeof(*ptr));
}

static void iwl_trans_pcie_queue_stuck_timer(unsigned long data)
{
	struct iwl_tx_queue *txq = (void *)data;
	struct iwl_queue *q = &txq->q;
	struct iwl_trans_pcie *trans_pcie = txq->trans_pcie;
	struct iwl_trans *trans = iwl_trans_pcie_get_trans(trans_pcie);
	u32 scd_sram_addr = trans_pcie->scd_base_addr +
		SCD_TX_STTS_MEM_LOWER_BOUND + (16 * txq->q.id);
	u8 buf[16];
	int i;

	spin_lock(&txq->lock);
	/* check if triggered erroneously */
	if (txq->q.read_ptr == txq->q.write_ptr) {
		spin_unlock(&txq->lock);
		return;
	}
	spin_unlock(&txq->lock);

	IWL_ERR(trans, "Queue %d stuck for %u ms.\n", txq->q.id,
		jiffies_to_msecs(trans_pcie->wd_timeout));
	IWL_ERR(trans, "Current SW read_ptr %d write_ptr %d\n",
		txq->q.read_ptr, txq->q.write_ptr);

	iwl_read_targ_mem_bytes(trans, scd_sram_addr, buf, sizeof(buf));

	iwl_print_hex_error(trans, buf, sizeof(buf));

	for (i = 0; i < FH_TCSR_CHNL_NUM; i++)
		IWL_ERR(trans, "FH TRBs(%d) = 0x%08x\n", i,
			iwl_read_direct32(trans, FH_TX_TRB_REG(i)));

	for (i = 0; i < trans->cfg->base_params->num_of_queues; i++) {
		u32 status = iwl_read_prph(trans, SCD_QUEUE_STATUS_BITS(i));
		u8 fifo = (status >> SCD_QUEUE_STTS_REG_POS_TXF) & 0x7;
		bool active = !!(status & BIT(SCD_QUEUE_STTS_REG_POS_ACTIVE));
		u32 tbl_dw =
			iwl_read_targ_mem(trans,
					  trans_pcie->scd_base_addr +
					  SCD_TRANS_TBL_OFFSET_QUEUE(i));

		if (i & 0x1)
			tbl_dw = (tbl_dw & 0xFFFF0000) >> 16;
		else
			tbl_dw = tbl_dw & 0x0000FFFF;

		IWL_ERR(trans,
			"Q %d is %sactive and mapped to fifo %d ra_tid 0x%04x [%d,%d]\n",
			i, active ? "" : "in", fifo, tbl_dw,
			iwl_read_prph(trans,
				      SCD_QUEUE_RDPTR(i)) & (txq->q.n_bd - 1),
			iwl_read_prph(trans, SCD_QUEUE_WRPTR(i)));
	}

	for (i = q->read_ptr; i != q->write_ptr;
	     i = iwl_queue_inc_wrap(i, q->n_bd)) {
		struct iwl_tx_cmd *tx_cmd =
			(struct iwl_tx_cmd *)txq->entries[i].cmd->payload;
		IWL_ERR(trans, "scratch %d = 0x%08x\n", i,
			get_unaligned_le32(&tx_cmd->scratch));
	}

	iwl_op_mode_nic_error(trans->op_mode);
}

static int iwl_trans_txq_alloc(struct iwl_trans *trans,
			       struct iwl_tx_queue *txq, int slots_num,
			       u32 txq_id)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	size_t tfd_sz = sizeof(struct iwl_tfd) * TFD_QUEUE_SIZE_MAX;
	int i;

	if (WARN_ON(txq->entries || txq->tfds))
		return -EINVAL;

	setup_timer(&txq->stuck_timer, iwl_trans_pcie_queue_stuck_timer,
		    (unsigned long)txq);
	txq->trans_pcie = trans_pcie;

	txq->q.n_window = slots_num;

	txq->entries = kcalloc(slots_num,
			       sizeof(struct iwl_pcie_tx_queue_entry),
			       GFP_KERNEL);

	if (!txq->entries)
		goto error;

	if (txq_id == trans_pcie->cmd_queue)
		for (i = 0; i < slots_num; i++) {
			txq->entries[i].cmd =
				kmalloc(sizeof(struct iwl_device_cmd),
					GFP_KERNEL);
			if (!txq->entries[i].cmd)
				goto error;
		}

	/* Circular buffer of transmit frame descriptors (TFDs),
	 * shared with device */
	txq->tfds = dma_alloc_coherent(trans->dev, tfd_sz,
				       &txq->q.dma_addr, GFP_KERNEL);
	if (!txq->tfds) {
		IWL_ERR(trans, "dma_alloc_coherent(%zd) failed\n", tfd_sz);
		goto error;
	}
	txq->q.id = txq_id;

	return 0;
error:
	if (txq->entries && txq_id == trans_pcie->cmd_queue)
		for (i = 0; i < slots_num; i++)
			kfree(txq->entries[i].cmd);
	kfree(txq->entries);
	txq->entries = NULL;

	return -ENOMEM;

}

static int iwl_trans_txq_init(struct iwl_trans *trans, struct iwl_tx_queue *txq,
			      int slots_num, u32 txq_id)
{
	int ret;

	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 */
	ret = iwl_queue_init(&txq->q, TFD_QUEUE_SIZE_MAX, slots_num,
			txq_id);
	if (ret)
		return ret;

	spin_lock_init(&txq->lock);

	/*
	 * Tell nic where to find circular buffer of Tx Frame Descriptors for
	 * given Tx queue, and enable the DMA channel used for that queue.
	 * Circular buffer (TFD queue in DRAM) physical base address */
	iwl_write_direct32(trans, FH_MEM_CBBC_QUEUE(txq_id),
			     txq->q.dma_addr >> 8);

	return 0;
}

/**
 * iwl_tx_queue_unmap -  Unmap any remaining DMA mappings and free skb's
 */
static void iwl_tx_queue_unmap(struct iwl_trans *trans, int txq_id)
{
	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;
	enum dma_data_direction dma_dir;

	if (!q->n_bd)
		return;

	/* In the command queue, all the TBs are mapped as BIDI
	 * so unmap them as such.
	 */
	if (txq_id == trans_pcie->cmd_queue)
		dma_dir = DMA_BIDIRECTIONAL;
	else
		dma_dir = DMA_TO_DEVICE;

	spin_lock_bh(&txq->lock);
	while (q->write_ptr != q->read_ptr) {
		iwl_txq_free_tfd(trans, txq, dma_dir);
		q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd);
	}
	spin_unlock_bh(&txq->lock);
}

/**
 * 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_trans *trans, int txq_id)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_tx_queue *txq = &trans_pcie->txq[txq_id];
	struct device *dev = trans->dev;
	int i;

	if (WARN_ON(!txq))
		return;

	iwl_tx_queue_unmap(trans, txq_id);

	/* De-alloc array of command/tx buffers */

	if (txq_id == trans_pcie->cmd_queue)
		for (i = 0; i < txq->q.n_window; i++)
			kfree(txq->entries[i].cmd);

	/* De-alloc circular buffer of TFDs */
	if (txq->q.n_bd) {
		dma_free_coherent(dev, sizeof(struct iwl_tfd) *
				  txq->q.n_bd, txq->tfds, txq->q.dma_addr);
		memset(&txq->q.dma_addr, 0, sizeof(txq->q.dma_addr));
	}

	kfree(txq->entries);
	txq->entries = NULL;

	del_timer_sync(&txq->stuck_timer);

	/* 0-fill queue descriptor structure */
	memset(txq, 0, sizeof(*txq));
}

/**
 * iwl_trans_tx_free - Free TXQ Context
 *
 * Destroy all TX DMA queues and structures
 */
static void iwl_trans_pcie_tx_free(struct iwl_trans *trans)
{
	int txq_id;
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	/* Tx queues */
	if (trans_pcie->txq) {
		for (txq_id = 0;
		     txq_id < trans->cfg->base_params->num_of_queues; txq_id++)
			iwl_tx_queue_free(trans, txq_id);
	}

	kfree(trans_pcie->txq);
	trans_pcie->txq = NULL;

	iwlagn_free_dma_ptr(trans, &trans_pcie->kw);

	iwlagn_free_dma_ptr(trans, &trans_pcie->scd_bc_tbls);
}

/**
 * iwl_trans_tx_alloc - allocate TX context
 * Allocate all Tx DMA structures and initialize them
 *
 * @param priv
 * @return error code
 */
static int iwl_trans_tx_alloc(struct iwl_trans *trans)
{
	int ret;
	int txq_id, slots_num;
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	u16 scd_bc_tbls_size = trans->cfg->base_params->num_of_queues *
			sizeof(struct iwlagn_scd_bc_tbl);

	/*It is not allowed to alloc twice, so warn when this happens.
	 * We cannot rely on the previous allocation, so free and fail */
	if (WARN_ON(trans_pcie->txq)) {
		ret = -EINVAL;
		goto error;
	}

	ret = iwlagn_alloc_dma_ptr(trans, &trans_pcie->scd_bc_tbls,
				   scd_bc_tbls_size);
	if (ret) {
		IWL_ERR(trans, "Scheduler BC Table allocation failed\n");
		goto error;
	}

	/* Alloc keep-warm buffer */
	ret = iwlagn_alloc_dma_ptr(trans, &trans_pcie->kw, IWL_KW_SIZE);
	if (ret) {
		IWL_ERR(trans, "Keep Warm allocation failed\n");
		goto error;
	}

	trans_pcie->txq = kcalloc(trans->cfg->base_params->num_of_queues,
				  sizeof(struct iwl_tx_queue), GFP_KERNEL);
	if (!trans_pcie->txq) {
		IWL_ERR(trans, "Not enough memory for txq\n");
		ret = ENOMEM;
		goto error;
	}

	/* Alloc and init all Tx queues, including the command queue (#4/#9) */
	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
	     txq_id++) {
		slots_num = (txq_id == trans_pcie->cmd_queue) ?
					TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
		ret = iwl_trans_txq_alloc(trans, &trans_pcie->txq[txq_id],
					  slots_num, txq_id);
		if (ret) {
			IWL_ERR(trans, "Tx %d queue alloc failed\n", txq_id);
			goto error;
		}
	}

	return 0;

error:
	iwl_trans_pcie_tx_free(trans);

	return ret;
}
static int iwl_tx_init(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int ret;
	int txq_id, slots_num;
	unsigned long flags;
	bool alloc = false;

	if (!trans_pcie->txq) {
		ret = iwl_trans_tx_alloc(trans);
		if (ret)
			goto error;
		alloc = true;
	}

	spin_lock_irqsave(&trans_pcie->irq_lock, flags);

	/* Turn off all Tx DMA fifos */
	iwl_write_prph(trans, SCD_TXFACT, 0);

	/* Tell NIC where to find the "keep warm" buffer */
	iwl_write_direct32(trans, FH_KW_MEM_ADDR_REG,
			   trans_pcie->kw.dma >> 4);

	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	/* Alloc and init all Tx queues, including the command queue (#4/#9) */
	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
	     txq_id++) {
		slots_num = (txq_id == trans_pcie->cmd_queue) ?
					TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
		ret = iwl_trans_txq_init(trans, &trans_pcie->txq[txq_id],
					 slots_num, txq_id);
		if (ret) {
			IWL_ERR(trans, "Tx %d queue init failed\n", txq_id);
			goto error;
		}
	}

	return 0;
error:
	/*Upon error, free only if we allocated something */
	if (alloc)
		iwl_trans_pcie_tx_free(trans);
	return ret;
}

static void iwl_set_pwr_vmain(struct iwl_trans *trans)
{
/*
 * (for documentation purposes)
 * to set power to V_AUX, do:

		if (pci_pme_capable(priv->pci_dev, PCI_D3cold))
			iwl_set_bits_mask_prph(trans, APMG_PS_CTRL_REG,
					       APMG_PS_CTRL_VAL_PWR_SRC_VAUX,
					       ~APMG_PS_CTRL_MSK_PWR_SRC);
 */

	iwl_set_bits_mask_prph(trans, APMG_PS_CTRL_REG,
			       APMG_PS_CTRL_VAL_PWR_SRC_VMAIN,
			       ~APMG_PS_CTRL_MSK_PWR_SRC);
}

/* PCI registers */
#define PCI_CFG_RETRY_TIMEOUT	0x041
#define PCI_CFG_LINK_CTRL_VAL_L0S_EN	0x01
#define PCI_CFG_LINK_CTRL_VAL_L1_EN	0x02

static u16 iwl_pciexp_link_ctrl(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	u16 pci_lnk_ctl;

	pcie_capability_read_word(trans_pcie->pci_dev, PCI_EXP_LNKCTL,
				  &pci_lnk_ctl);
	return pci_lnk_ctl;
}

static void iwl_apm_config(struct iwl_trans *trans)
{
	/*
	 * HW bug W/A for instability in PCIe bus L0S->L1 transition.
	 * Check if BIOS (or OS) enabled L1-ASPM on this device.
	 * If so (likely), disable L0S, so device moves directly L0->L1;
	 *    costs negligible amount of power savings.
	 * If not (unlikely), enable L0S, so there is at least some
	 *    power savings, even without L1.
	 */
	u16 lctl = iwl_pciexp_link_ctrl(trans);

	if ((lctl & PCI_CFG_LINK_CTRL_VAL_L1_EN) ==
				PCI_CFG_LINK_CTRL_VAL_L1_EN) {
		/* L1-ASPM enabled; disable(!) L0S */
		iwl_set_bit(trans, CSR_GIO_REG, CSR_GIO_REG_VAL_L0S_ENABLED);
		dev_printk(KERN_INFO, trans->dev,
			   "L1 Enabled; Disabling L0S\n");
	} else {
		/* L1-ASPM disabled; enable(!) L0S */
		iwl_clear_bit(trans, CSR_GIO_REG, CSR_GIO_REG_VAL_L0S_ENABLED);
		dev_printk(KERN_INFO, trans->dev,
			   "L1 Disabled; Enabling L0S\n");
	}
	trans->pm_support = !(lctl & PCI_CFG_LINK_CTRL_VAL_L0S_EN);
}

/*
 * Start up NIC's basic functionality after it has been reset
 * (e.g. after platform boot, or shutdown via iwl_apm_stop())
 * NOTE:  This does not load uCode nor start the embedded processor
 */
static int iwl_apm_init(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int ret = 0;
	IWL_DEBUG_INFO(trans, "Init card's basic functions\n");

	/*
	 * Use "set_bit" below rather than "write", to preserve any hardware
	 * bits already set by default after reset.
	 */

	/* Disable L0S exit timer (platform NMI Work/Around) */
	iwl_set_bit(trans, CSR_GIO_CHICKEN_BITS,
		    CSR_GIO_CHICKEN_BITS_REG_BIT_DIS_L0S_EXIT_TIMER);

	/*
	 * Disable L0s without affecting L1;
	 *  don't wait for ICH L0s (ICH bug W/A)
	 */
	iwl_set_bit(trans, CSR_GIO_CHICKEN_BITS,
		    CSR_GIO_CHICKEN_BITS_REG_BIT_L1A_NO_L0S_RX);

	/* Set FH wait threshold to maximum (HW error during stress W/A) */
	iwl_set_bit(trans, CSR_DBG_HPET_MEM_REG, CSR_DBG_HPET_MEM_REG_VAL);

	/*
	 * Enable HAP INTA (interrupt from management bus) to
	 * wake device's PCI Express link L1a -> L0s
	 */
	iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
		    CSR_HW_IF_CONFIG_REG_BIT_HAP_WAKE_L1A);

	iwl_apm_config(trans);

	/* Configure analog phase-lock-loop before activating to D0A */
	if (trans->cfg->base_params->pll_cfg_val)
		iwl_set_bit(trans, CSR_ANA_PLL_CFG,
			    trans->cfg->base_params->pll_cfg_val);

	/*
	 * Set "initialization complete" bit to move adapter from
	 * D0U* --> D0A* (powered-up active) state.
	 */
	iwl_set_bit(trans, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_INIT_DONE);

	/*
	 * Wait for clock stabilization; once stabilized, access to
	 * device-internal resources is supported, e.g. iwl_write_prph()
	 * and accesses to uCode SRAM.
	 */
	ret = iwl_poll_bit(trans, CSR_GP_CNTRL,
			   CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY,
			   CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY, 25000);
	if (ret < 0) {
		IWL_DEBUG_INFO(trans, "Failed to init the card\n");
		goto out;
	}

	/*
	 * Enable DMA clock and wait for it to stabilize.
	 *
	 * Write to "CLK_EN_REG"; "1" bits enable clocks, while "0" bits
	 * do not disable clocks.  This preserves any hardware bits already
	 * set by default in "CLK_CTRL_REG" after reset.
	 */
	iwl_write_prph(trans, APMG_CLK_EN_REG, APMG_CLK_VAL_DMA_CLK_RQT);
	udelay(20);

	/* Disable L1-Active */
	iwl_set_bits_prph(trans, APMG_PCIDEV_STT_REG,
			  APMG_PCIDEV_STT_VAL_L1_ACT_DIS);

	set_bit(STATUS_DEVICE_ENABLED, &trans_pcie->status);

out:
	return ret;
}

static int iwl_apm_stop_master(struct iwl_trans *trans)
{
	int ret = 0;

	/* stop device's busmaster DMA activity */
	iwl_set_bit(trans, CSR_RESET, CSR_RESET_REG_FLAG_STOP_MASTER);

	ret = iwl_poll_bit(trans, CSR_RESET,
			   CSR_RESET_REG_FLAG_MASTER_DISABLED,
			   CSR_RESET_REG_FLAG_MASTER_DISABLED, 100);
	if (ret)
		IWL_WARN(trans, "Master Disable Timed Out, 100 usec\n");

	IWL_DEBUG_INFO(trans, "stop master\n");

	return ret;
}

static void iwl_apm_stop(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	IWL_DEBUG_INFO(trans, "Stop card, put in low power state\n");

	clear_bit(STATUS_DEVICE_ENABLED, &trans_pcie->status);

	/* Stop device's DMA activity */
	iwl_apm_stop_master(trans);

	/* Reset the entire device */
	iwl_set_bit(trans, CSR_RESET, CSR_RESET_REG_FLAG_SW_RESET);

	udelay(10);

	/*
	 * Clear "initialization complete" bit to move adapter from
	 * D0A* (powered-up Active) --> D0U* (Uninitialized) state.
	 */
	iwl_clear_bit(trans, CSR_GP_CNTRL,
		      CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
}

static int iwl_nic_init(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	unsigned long flags;

	/* nic_init */
	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
	iwl_apm_init(trans);

	/* Set interrupt coalescing calibration timer to default (512 usecs) */
	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_CALIB_TIMEOUT_DEF);

	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	iwl_set_pwr_vmain(trans);

	iwl_op_mode_nic_config(trans->op_mode);

#ifndef CONFIG_IWLWIFI_IDI
	/* Allocate the RX queue, or reset if it is already allocated */
	iwl_rx_init(trans);
#endif

	/* Allocate or reset and init all Tx and Command queues */
	if (iwl_tx_init(trans))
		return -ENOMEM;

	if (trans->cfg->base_params->shadow_reg_enable) {
		/* enable shadow regs in HW */
		iwl_set_bit(trans, CSR_MAC_SHADOW_REG_CTRL, 0x800FFFFF);
		IWL_DEBUG_INFO(trans, "Enabling shadow registers in device\n");
	}

	return 0;
}

#define HW_READY_TIMEOUT (50)

/* Note: returns poll_bit return value, which is >= 0 if success */
static int iwl_set_hw_ready(struct iwl_trans *trans)
{
	int ret;

	iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
		    CSR_HW_IF_CONFIG_REG_BIT_NIC_READY);

	/* See if we got it */
	ret = iwl_poll_bit(trans, CSR_HW_IF_CONFIG_REG,
			   CSR_HW_IF_CONFIG_REG_BIT_NIC_READY,
			   CSR_HW_IF_CONFIG_REG_BIT_NIC_READY,
			   HW_READY_TIMEOUT);

	IWL_DEBUG_INFO(trans, "hardware%s ready\n", ret < 0 ? " not" : "");
	return ret;
}

/* Note: returns standard 0/-ERROR code */
static int iwl_prepare_card_hw(struct iwl_trans *trans)
{
	int ret;

	IWL_DEBUG_INFO(trans, "iwl_trans_prepare_card_hw enter\n");

	ret = iwl_set_hw_ready(trans);
	/* If the card is ready, exit 0 */
	if (ret >= 0)
		return 0;

	/* If HW is not ready, prepare the conditions to check again */
	iwl_set_bit(trans, CSR_HW_IF_CONFIG_REG,
		    CSR_HW_IF_CONFIG_REG_PREPARE);

	ret = iwl_poll_bit(trans, CSR_HW_IF_CONFIG_REG,
			   ~CSR_HW_IF_CONFIG_REG_BIT_NIC_PREPARE_DONE,
			   CSR_HW_IF_CONFIG_REG_BIT_NIC_PREPARE_DONE, 150000);

	if (ret < 0)
		return ret;

	/* HW should be ready by now, check again. */
	ret = iwl_set_hw_ready(trans);
	if (ret >= 0)
		return 0;
	return ret;
}

/*
 * ucode
 */
static int iwl_load_section(struct iwl_trans *trans, u8 section_num,
			    const struct fw_desc *section)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	dma_addr_t phy_addr = section->p_addr;
	u32 byte_cnt = section->len;
	u32 dst_addr = section->offset;
	int ret;

	trans_pcie->ucode_write_complete = false;

	iwl_write_direct32(trans,
			   FH_TCSR_CHNL_TX_CONFIG_REG(FH_SRVC_CHNL),
			   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_PAUSE);

	iwl_write_direct32(trans,
			   FH_SRVC_CHNL_SRAM_ADDR_REG(FH_SRVC_CHNL),
			   dst_addr);

	iwl_write_direct32(trans,
		FH_TFDIB_CTRL0_REG(FH_SRVC_CHNL),
		phy_addr & FH_MEM_TFDIB_DRAM_ADDR_LSB_MSK);

	iwl_write_direct32(trans,
			   FH_TFDIB_CTRL1_REG(FH_SRVC_CHNL),
			   (iwl_get_dma_hi_addr(phy_addr)
				<< FH_MEM_TFDIB_REG1_ADDR_BITSHIFT) | byte_cnt);

	iwl_write_direct32(trans,
			   FH_TCSR_CHNL_TX_BUF_STS_REG(FH_SRVC_CHNL),
			   1 << FH_TCSR_CHNL_TX_BUF_STS_REG_POS_TB_NUM |
			   1 << FH_TCSR_CHNL_TX_BUF_STS_REG_POS_TB_IDX |
			   FH_TCSR_CHNL_TX_BUF_STS_REG_VAL_TFDB_VALID);

	iwl_write_direct32(trans,
			   FH_TCSR_CHNL_TX_CONFIG_REG(FH_SRVC_CHNL),
			   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_ENABLE	|
			   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_DISABLE	|
			   FH_TCSR_TX_CONFIG_REG_VAL_CIRQ_HOST_ENDTFD);

	IWL_DEBUG_FW(trans, "[%d] uCode section being loaded...\n",
		     section_num);
	ret = wait_event_timeout(trans_pcie->ucode_write_waitq,
				 trans_pcie->ucode_write_complete, 5 * HZ);
	if (!ret) {
		IWL_ERR(trans, "Could not load the [%d] uCode section\n",
			section_num);
		return -ETIMEDOUT;
	}

	return 0;
}

static int iwl_load_given_ucode(struct iwl_trans *trans,
				const struct fw_img *image)
{
	int ret = 0;
		int i;

		for (i = 0; i < IWL_UCODE_SECTION_MAX; i++) {
			if (!image->sec[i].p_addr)
				break;

			ret = iwl_load_section(trans, i, &image->sec[i]);
			if (ret)
				return ret;
		}

	/* Remove all resets to allow NIC to operate */
	iwl_write32(trans, CSR_RESET, 0);

	return 0;
}

static int iwl_trans_pcie_start_fw(struct iwl_trans *trans,
				   const struct fw_img *fw)
{
	int ret;
	bool hw_rfkill;

	/* This may fail if AMT took ownership of the device */
	if (iwl_prepare_card_hw(trans)) {
		IWL_WARN(trans, "Exit HW not ready\n");
		return -EIO;
	}

	iwl_enable_rfkill_int(trans);

	/* If platform's RF_KILL switch is NOT set to KILL */
	hw_rfkill = iwl_is_rfkill_set(trans);
	iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill);
	if (hw_rfkill)
		return -ERFKILL;

	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);

	ret = iwl_nic_init(trans);
	if (ret) {
		IWL_ERR(trans, "Unable to init nic\n");
		return ret;
	}

	/* make sure rfkill handshake bits are cleared */
	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR,
		    CSR_UCODE_DRV_GP1_BIT_CMD_BLOCKED);

	/* clear (again), then enable host interrupts */
	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);
	iwl_enable_interrupts(trans);

	/* really make sure rfkill handshake bits are cleared */
	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);
	iwl_write32(trans, CSR_UCODE_DRV_GP1_CLR, CSR_UCODE_SW_BIT_RFKILL);

	/* Load the given image to the HW */
	return iwl_load_given_ucode(trans, fw);
}

/*
 * Activate/Deactivate Tx DMA/FIFO channels according tx fifos mask
 */
static void iwl_trans_txq_set_sched(struct iwl_trans *trans, u32 mask)
{
	struct iwl_trans_pcie __maybe_unused *trans_pcie =
		IWL_TRANS_GET_PCIE_TRANS(trans);

	iwl_write_prph(trans, SCD_TXFACT, mask);
}

static void iwl_tx_start(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	u32 a;
	int chan;
	u32 reg_val;

	/* make sure all queue are not stopped/used */
	memset(trans_pcie->queue_stopped, 0, sizeof(trans_pcie->queue_stopped));
	memset(trans_pcie->queue_used, 0, sizeof(trans_pcie->queue_used));

	trans_pcie->scd_base_addr =
		iwl_read_prph(trans, SCD_SRAM_BASE_ADDR);
	a = trans_pcie->scd_base_addr + SCD_CONTEXT_MEM_LOWER_BOUND;
	/* reset conext data memory */
	for (; a < trans_pcie->scd_base_addr + SCD_CONTEXT_MEM_UPPER_BOUND;
		a += 4)
		iwl_write_targ_mem(trans, a, 0);
	/* reset tx status memory */
	for (; a < trans_pcie->scd_base_addr + SCD_TX_STTS_MEM_UPPER_BOUND;
		a += 4)
		iwl_write_targ_mem(trans, a, 0);
	for (; a < trans_pcie->scd_base_addr +
	       SCD_TRANS_TBL_OFFSET_QUEUE(
				trans->cfg->base_params->num_of_queues);
	       a += 4)
		iwl_write_targ_mem(trans, a, 0);

	iwl_write_prph(trans, SCD_DRAM_BASE_ADDR,
		       trans_pcie->scd_bc_tbls.dma >> 10);

	/* The chain extension of the SCD doesn't work well. This feature is
	 * enabled by default by the HW, so we need to disable it manually.
	 */
	iwl_write_prph(trans, SCD_CHAINEXT_EN, 0);

	iwl_trans_ac_txq_enable(trans, trans_pcie->cmd_queue,
				trans_pcie->cmd_fifo);

	/* Activate all Tx DMA/FIFO channels */
	iwl_trans_txq_set_sched(trans, IWL_MASK(0, 7));

	/* Enable DMA channel */
	for (chan = 0; chan < FH_TCSR_CHNL_NUM ; chan++)
		iwl_write_direct32(trans, FH_TCSR_CHNL_TX_CONFIG_REG(chan),
				   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_ENABLE |
				   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_ENABLE);

	/* Update FH chicken bits */
	reg_val = iwl_read_direct32(trans, FH_TX_CHICKEN_BITS_REG);
	iwl_write_direct32(trans, FH_TX_CHICKEN_BITS_REG,
			   reg_val | FH_TX_CHICKEN_BITS_SCD_AUTO_RETRY_EN);

	/* Enable L1-Active */
	iwl_clear_bits_prph(trans, APMG_PCIDEV_STT_REG,
			    APMG_PCIDEV_STT_VAL_L1_ACT_DIS);
}

static void iwl_trans_pcie_fw_alive(struct iwl_trans *trans)
{
	iwl_reset_ict(trans);
	iwl_tx_start(trans);
}

/**
 * iwlagn_txq_ctx_stop - Stop all Tx DMA channels
 */
static int iwl_trans_tx_stop(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int ch, txq_id, ret;
	unsigned long flags;

	/* Turn off all Tx DMA fifos */
	spin_lock_irqsave(&trans_pcie->irq_lock, flags);

	iwl_trans_txq_set_sched(trans, 0);

	/* Stop each Tx DMA channel, and wait for it to be idle */
	for (ch = 0; ch < FH_TCSR_CHNL_NUM; ch++) {
		iwl_write_direct32(trans,
				   FH_TCSR_CHNL_TX_CONFIG_REG(ch), 0x0);
		ret = iwl_poll_direct_bit(trans, FH_TSSR_TX_STATUS_REG,
			FH_TSSR_TX_STATUS_REG_MSK_CHNL_IDLE(ch), 1000);
		if (ret < 0)
			IWL_ERR(trans,
				"Failing on timeout while stopping DMA channel %d [0x%08x]\n",
				ch,
				iwl_read_direct32(trans,
						  FH_TSSR_TX_STATUS_REG));
	}
	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	if (!trans_pcie->txq) {
		IWL_WARN(trans,
			 "Stopping tx queues that aren't allocated...\n");
		return 0;
	}

	/* Unmap DMA from host system and free skb's */
	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
	     txq_id++)
		iwl_tx_queue_unmap(trans, txq_id);

	return 0;
}

static void iwl_trans_pcie_stop_device(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	unsigned long flags;

	/* tell the device to stop sending interrupts */
	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
	iwl_disable_interrupts(trans);
	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	/* device going down, Stop using ICT table */
	iwl_disable_ict(trans);

	/*
	 * If a HW restart happens during firmware loading,
	 * then the firmware loading might call this function
	 * and later it might be called again due to the
	 * restart. So don't process again if the device is
	 * already dead.
	 */
	if (test_bit(STATUS_DEVICE_ENABLED, &trans_pcie->status)) {
		iwl_trans_tx_stop(trans);
#ifndef CONFIG_IWLWIFI_IDI
		iwl_trans_rx_stop(trans);
#endif
		/* Power-down device's busmaster DMA clocks */
		iwl_write_prph(trans, APMG_CLK_DIS_REG,
			       APMG_CLK_VAL_DMA_CLK_RQT);
		udelay(5);
	}

	/* Make sure (redundant) we've released our request to stay awake */
	iwl_clear_bit(trans, CSR_GP_CNTRL,
		      CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);

	/* Stop the device, and put it in low power state */
	iwl_apm_stop(trans);

	/* Upon stop, the APM issues an interrupt if HW RF kill is set.
	 * Clean again the interrupt here
	 */
	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
	iwl_disable_interrupts(trans);
	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	iwl_enable_rfkill_int(trans);

	/* wait to make sure we flush pending tasklet*/
	synchronize_irq(trans_pcie->irq);
	tasklet_kill(&trans_pcie->irq_tasklet);

	cancel_work_sync(&trans_pcie->rx_replenish);

	/* stop and reset the on-board processor */
	iwl_write32(trans, CSR_RESET, CSR_RESET_REG_FLAG_NEVO_RESET);

	/* clear all status bits */
	clear_bit(STATUS_HCMD_ACTIVE, &trans_pcie->status);
	clear_bit(STATUS_INT_ENABLED, &trans_pcie->status);
	clear_bit(STATUS_DEVICE_ENABLED, &trans_pcie->status);
	clear_bit(STATUS_TPOWER_PMI, &trans_pcie->status);
}

static void iwl_trans_pcie_wowlan_suspend(struct iwl_trans *trans)
{
	/* let the ucode operate on its own */
	iwl_write32(trans, CSR_UCODE_DRV_GP1_SET,
		    CSR_UCODE_DRV_GP1_BIT_D3_CFG_COMPLETE);

	iwl_disable_interrupts(trans);
	iwl_clear_bit(trans, CSR_GP_CNTRL,
		      CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
}

static int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb,
			     struct iwl_device_cmd *dev_cmd, int txq_id)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
	struct iwl_tx_cmd *tx_cmd = (struct iwl_tx_cmd *) dev_cmd->payload;
	struct iwl_cmd_meta *out_meta;
	struct iwl_tx_queue *txq;
	struct iwl_queue *q;
	dma_addr_t phys_addr = 0;
	dma_addr_t txcmd_phys;
	dma_addr_t scratch_phys;
	u16 len, firstlen, secondlen;
	u8 wait_write_ptr = 0;
	__le16 fc = hdr->frame_control;
	u8 hdr_len = ieee80211_hdrlen(fc);
	u16 __maybe_unused wifi_seq;

	txq = &trans_pcie->txq[txq_id];
	q = &txq->q;

	if (unlikely(!test_bit(txq_id, trans_pcie->queue_used))) {
		WARN_ON_ONCE(1);
		return -EINVAL;
	}

	spin_lock(&txq->lock);

	/* In AGG mode, the index in the ring must correspond to the WiFi
	 * sequence number. This is a HW requirements to help the SCD to parse
	 * the BA.
	 * Check here that the packets are in the right place on the ring.
	 */
#ifdef CONFIG_IWLWIFI_DEBUG
	wifi_seq = SEQ_TO_SN(le16_to_cpu(hdr->seq_ctrl));
	WARN_ONCE((iwl_read_prph(trans, SCD_AGGR_SEL) & BIT(txq_id)) &&
		  ((wifi_seq & 0xff) != q->write_ptr),
		  "Q: %d WiFi Seq %d tfdNum %d",
		  txq_id, wifi_seq, q->write_ptr);
#endif

	/* Set up driver data for this TFD */
	txq->entries[q->write_ptr].skb = skb;
	txq->entries[q->write_ptr].cmd = dev_cmd;

	dev_cmd->hdr.cmd = REPLY_TX;
	dev_cmd->hdr.sequence =
		cpu_to_le16((u16)(QUEUE_TO_SEQ(txq_id) |
			    INDEX_TO_SEQ(q->write_ptr)));

	/* Set up first empty entry in queue's array of Tx/cmd buffers */
	out_meta = &txq->entries[q->write_ptr].meta;

	/*
	 * 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 = dma_map_single(trans->dev,
				    &dev_cmd->hdr, firstlen,
				    DMA_BIDIRECTIONAL);
	if (unlikely(dma_mapping_error(trans->dev, txcmd_phys)))
		goto out_err;
	dma_unmap_addr_set(out_meta, mapping, txcmd_phys);
	dma_unmap_len_set(out_meta, len, firstlen);

	if (!ieee80211_has_morefrags(fc)) {
		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 = dma_map_single(trans->dev, skb->data + hdr_len,
					   secondlen, DMA_TO_DEVICE);
		if (unlikely(dma_mapping_error(trans->dev, phys_addr))) {
			dma_unmap_single(trans->dev,
					 dma_unmap_addr(out_meta, mapping),
					 dma_unmap_len(out_meta, len),
					 DMA_BIDIRECTIONAL);
			goto out_err;
		}
	}

	/* Attach buffers to TFD */
	iwlagn_txq_attach_buf_to_tfd(trans, txq, txcmd_phys, firstlen, 1);
	if (secondlen > 0)
		iwlagn_txq_attach_buf_to_tfd(trans, txq, phys_addr,
					     secondlen, 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 */
	dma_sync_single_for_cpu(trans->dev, txcmd_phys, firstlen,
				DMA_BIDIRECTIONAL);
	tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
	tx_cmd->dram_msb_ptr = iwl_get_dma_hi_addr(scratch_phys);

	IWL_DEBUG_TX(trans, "sequence nr = 0X%x\n",
		     le16_to_cpu(dev_cmd->hdr.sequence));
	IWL_DEBUG_TX(trans, "tx_flags = 0X%x\n", le32_to_cpu(tx_cmd->tx_flags));

	/* Set up entry for this TFD in Tx byte-count array */
	iwl_trans_txq_update_byte_cnt_tbl(trans, txq, le16_to_cpu(tx_cmd->len));

	dma_sync_single_for_device(trans->dev, txcmd_phys, firstlen,
				   DMA_BIDIRECTIONAL);

	trace_iwlwifi_dev_tx(trans->dev,
			     &txq->tfds[txq->q.write_ptr],
			     sizeof(struct iwl_tfd),
			     &dev_cmd->hdr, firstlen,
			     skb->data + hdr_len, secondlen);

	/* start timer if queue currently empty */
	if (txq->need_update && q->read_ptr == q->write_ptr &&
	    trans_pcie->wd_timeout)
		mod_timer(&txq->stuck_timer, jiffies + trans_pcie->wd_timeout);

	/* Tell device the write index *just past* this latest filled TFD */
	q->write_ptr = iwl_queue_inc_wrap(q->write_ptr, q->n_bd);
	iwl_txq_update_write_ptr(trans, txq);

	/*
	 * 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.
	 */
	if (iwl_queue_space(q) < q->high_mark) {
		if (wait_write_ptr) {
			txq->need_update = 1;
			iwl_txq_update_write_ptr(trans, txq);
		} else {
			iwl_stop_queue(trans, txq);
		}
	}
	spin_unlock(&txq->lock);
	return 0;
 out_err:
	spin_unlock(&txq->lock);
	return -1;
}

static int iwl_trans_pcie_start_hw(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	int err;
	bool hw_rfkill;

	trans_pcie->inta_mask = CSR_INI_SET_MASK;

	if (!trans_pcie->irq_requested) {
		tasklet_init(&trans_pcie->irq_tasklet, (void (*)(unsigned long))
			iwl_irq_tasklet, (unsigned long)trans);

		iwl_alloc_isr_ict(trans);

		err = request_irq(trans_pcie->irq, iwl_isr_ict, IRQF_SHARED,
				  DRV_NAME, trans);
		if (err) {
			IWL_ERR(trans, "Error allocating IRQ %d\n",
				trans_pcie->irq);
			goto error;
		}

		INIT_WORK(&trans_pcie->rx_replenish, iwl_bg_rx_replenish);
		trans_pcie->irq_requested = true;
	}

	err = iwl_prepare_card_hw(trans);
	if (err) {
		IWL_ERR(trans, "Error while preparing HW: %d\n", err);
		goto err_free_irq;
	}

	iwl_apm_init(trans);

	/* From now on, the op_mode will be kept updated about RF kill state */
	iwl_enable_rfkill_int(trans);

	hw_rfkill = iwl_is_rfkill_set(trans);
	iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill);

	return err;

err_free_irq:
	trans_pcie->irq_requested = false;
	free_irq(trans_pcie->irq, trans);
error:
	iwl_free_isr_ict(trans);
	tasklet_kill(&trans_pcie->irq_tasklet);
	return err;
}

static void iwl_trans_pcie_stop_hw(struct iwl_trans *trans,
				   bool op_mode_leaving)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	bool hw_rfkill;
	unsigned long flags;

	iwl_apm_stop(trans);

	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
	iwl_disable_interrupts(trans);
	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);

	iwl_write32(trans, CSR_INT, 0xFFFFFFFF);

	if (!op_mode_leaving) {
		/*
		 * Even if we stop the HW, we still want the RF kill
		 * interrupt
		 */
		iwl_enable_rfkill_int(trans);

		/*
		 * Check again since the RF kill state may have changed while
		 * all the interrupts were disabled, in this case we couldn't
		 * receive the RF kill interrupt and update the state in the
		 * op_mode.
		 */
		hw_rfkill = iwl_is_rfkill_set(trans);
		iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill);
	}
}

static void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn,
				   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];
	/* n_bd is usually 256 => n_bd - 1 = 0xff */
	int tfd_num = ssn & (txq->q.n_bd - 1);
	int freed = 0;

	spin_lock(&txq->lock);

	if (txq->q.read_ptr != tfd_num) {
		IWL_DEBUG_TX_REPLY(trans, "[Q %d] %d -> %d (%d)\n",
				   txq_id, txq->q.read_ptr, tfd_num, ssn);
		freed = iwl_tx_queue_reclaim(trans, txq_id, tfd_num, skbs);
		if (iwl_queue_space(&txq->q) > txq->q.low_mark)
			iwl_wake_queue(trans, txq);
	}

	spin_unlock(&txq->lock);
}

static void iwl_trans_pcie_write8(struct iwl_trans *trans, u32 ofs, u8 val)
{
	writeb(val, IWL_TRANS_GET_PCIE_TRANS(trans)->hw_base + ofs);
}

static void iwl_trans_pcie_write32(struct iwl_trans *trans, u32 ofs, u32 val)
{
	writel(val, IWL_TRANS_GET_PCIE_TRANS(trans)->hw_base + ofs);
}

static u32 iwl_trans_pcie_read32(struct iwl_trans *trans, u32 ofs)
{
	return readl(IWL_TRANS_GET_PCIE_TRANS(trans)->hw_base + ofs);
}

static void iwl_trans_pcie_configure(struct iwl_trans *trans,
				     const struct iwl_trans_config *trans_cfg)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	trans_pcie->cmd_queue = trans_cfg->cmd_queue;
	trans_pcie->cmd_fifo = trans_cfg->cmd_fifo;
	if (WARN_ON(trans_cfg->n_no_reclaim_cmds > MAX_NO_RECLAIM_CMDS))
		trans_pcie->n_no_reclaim_cmds = 0;
	else
		trans_pcie->n_no_reclaim_cmds = trans_cfg->n_no_reclaim_cmds;
	if (trans_pcie->n_no_reclaim_cmds)
		memcpy(trans_pcie->no_reclaim_cmds, trans_cfg->no_reclaim_cmds,
		       trans_pcie->n_no_reclaim_cmds * sizeof(u8));

	trans_pcie->rx_buf_size_8k = trans_cfg->rx_buf_size_8k;
	if (trans_pcie->rx_buf_size_8k)
		trans_pcie->rx_page_order = get_order(8 * 1024);
	else
		trans_pcie->rx_page_order = get_order(4 * 1024);

	trans_pcie->wd_timeout =
		msecs_to_jiffies(trans_cfg->queue_watchdog_timeout);

	trans_pcie->command_names = trans_cfg->command_names;
}

void iwl_trans_pcie_free(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	iwl_trans_pcie_tx_free(trans);
#ifndef CONFIG_IWLWIFI_IDI
	iwl_trans_pcie_rx_free(trans);
#endif
	if (trans_pcie->irq_requested == true) {
		free_irq(trans_pcie->irq, trans);
		iwl_free_isr_ict(trans);
	}

	pci_disable_msi(trans_pcie->pci_dev);
	iounmap(trans_pcie->hw_base);
	pci_release_regions(trans_pcie->pci_dev);
	pci_disable_device(trans_pcie->pci_dev);
	kmem_cache_destroy(trans->dev_cmd_pool);

	kfree(trans);
}

static void iwl_trans_pcie_set_pmi(struct iwl_trans *trans, bool state)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	if (state)
		set_bit(STATUS_TPOWER_PMI, &trans_pcie->status);
	else
		clear_bit(STATUS_TPOWER_PMI, &trans_pcie->status);
}

#ifdef CONFIG_PM_SLEEP
static int iwl_trans_pcie_suspend(struct iwl_trans *trans)
{
	return 0;
}

static int iwl_trans_pcie_resume(struct iwl_trans *trans)
{
	bool hw_rfkill;

	iwl_enable_rfkill_int(trans);

	hw_rfkill = iwl_is_rfkill_set(trans);
	iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill);

	if (!hw_rfkill)
		iwl_enable_interrupts(trans);

	return 0;
}
#endif /* CONFIG_PM_SLEEP */

#define IWL_FLUSH_WAIT_MS	2000

static int iwl_trans_pcie_wait_tx_queue_empty(struct iwl_trans *trans)
{
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_tx_queue *txq;
	struct iwl_queue *q;
	int cnt;
	unsigned long now = jiffies;
	int ret = 0;

	/* waiting for all the tx frames complete might take a while */
	for (cnt = 0; cnt < trans->cfg->base_params->num_of_queues; cnt++) {
		if (cnt == trans_pcie->cmd_queue)
			continue;
		txq = &trans_pcie->txq[cnt];
		q = &txq->q;
		while (q->read_ptr != q->write_ptr && !time_after(jiffies,
		       now + msecs_to_jiffies(IWL_FLUSH_WAIT_MS)))
			msleep(1);

		if (q->read_ptr != q->write_ptr) {
			IWL_ERR(trans, "fail to flush all tx fifo queues\n");
			ret = -ETIMEDOUT;
			break;
		}
	}
	return ret;
}

static const char *get_fh_string(int cmd)
{
#define IWL_CMD(x) case x: return #x
	switch (cmd) {
	IWL_CMD(FH_RSCSR_CHNL0_STTS_WPTR_REG);
	IWL_CMD(FH_RSCSR_CHNL0_RBDCB_BASE_REG);
	IWL_CMD(FH_RSCSR_CHNL0_WPTR);
	IWL_CMD(FH_MEM_RCSR_CHNL0_CONFIG_REG);
	IWL_CMD(FH_MEM_RSSR_SHARED_CTRL_REG);
	IWL_CMD(FH_MEM_RSSR_RX_STATUS_REG);
	IWL_CMD(FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV);
	IWL_CMD(FH_TSSR_TX_STATUS_REG);
	IWL_CMD(FH_TSSR_TX_ERROR_REG);
	default:
		return "UNKNOWN";
	}
#undef IWL_CMD
}

int iwl_dump_fh(struct iwl_trans *trans, char **buf)
{
	int i;
	static const u32 fh_tbl[] = {
		FH_RSCSR_CHNL0_STTS_WPTR_REG,
		FH_RSCSR_CHNL0_RBDCB_BASE_REG,
		FH_RSCSR_CHNL0_WPTR,
		FH_MEM_RCSR_CHNL0_CONFIG_REG,
		FH_MEM_RSSR_SHARED_CTRL_REG,
		FH_MEM_RSSR_RX_STATUS_REG,
		FH_MEM_RSSR_RX_ENABLE_ERR_IRQ2DRV,
		FH_TSSR_TX_STATUS_REG,
		FH_TSSR_TX_ERROR_REG
	};

#ifdef CONFIG_IWLWIFI_DEBUGFS
	if (buf) {
		int pos = 0;
		size_t bufsz = ARRAY_SIZE(fh_tbl) * 48 + 40;

		*buf = kmalloc(bufsz, GFP_KERNEL);
		if (!*buf)
			return -ENOMEM;

		pos += scnprintf(*buf + pos, bufsz - pos,
				"FH register values:\n");

		for (i = 0; i < ARRAY_SIZE(fh_tbl); i++)
			pos += scnprintf(*buf + pos, bufsz - pos,
				"  %34s: 0X%08x\n",
				get_fh_string(fh_tbl[i]),
				iwl_read_direct32(trans, fh_tbl[i]));

		return pos;
	}
#endif

	IWL_ERR(trans, "FH register values:\n");
	for (i = 0; i <  ARRAY_SIZE(fh_tbl); i++)
		IWL_ERR(trans, "  %34s: 0X%08x\n",
			get_fh_string(fh_tbl[i]),
			iwl_read_direct32(trans, fh_tbl[i]));

	return 0;
}

static const char *get_csr_string(int cmd)
{
#define IWL_CMD(x) case x: return #x
	switch (cmd) {
	IWL_CMD(CSR_HW_IF_CONFIG_REG);
	IWL_CMD(CSR_INT_COALESCING);
	IWL_CMD(CSR_INT);
	IWL_CMD(CSR_INT_MASK);
	IWL_CMD(CSR_FH_INT_STATUS);
	IWL_CMD(CSR_GPIO_IN);
	IWL_CMD(CSR_RESET);
	IWL_CMD(CSR_GP_CNTRL);
	IWL_CMD(CSR_HW_REV);
	IWL_CMD(CSR_EEPROM_REG);
	IWL_CMD(CSR_EEPROM_GP);
	IWL_CMD(CSR_OTP_GP_REG);
	IWL_CMD(CSR_GIO_REG);
	IWL_CMD(CSR_GP_UCODE_REG);
	IWL_CMD(CSR_GP_DRIVER_REG);
	IWL_CMD(CSR_UCODE_DRV_GP1);
	IWL_CMD(CSR_UCODE_DRV_GP2);
	IWL_CMD(CSR_LED_REG);
	IWL_CMD(CSR_DRAM_INT_TBL_REG);
	IWL_CMD(CSR_GIO_CHICKEN_BITS);
	IWL_CMD(CSR_ANA_PLL_CFG);
	IWL_CMD(CSR_HW_REV_WA_REG);
	IWL_CMD(CSR_DBG_HPET_MEM_REG);
	default:
		return "UNKNOWN";
	}
#undef IWL_CMD
}

void iwl_dump_csr(struct iwl_trans *trans)
{
	int i;
	static const u32 csr_tbl[] = {
		CSR_HW_IF_CONFIG_REG,
		CSR_INT_COALESCING,
		CSR_INT,
		CSR_INT_MASK,
		CSR_FH_INT_STATUS,
		CSR_GPIO_IN,
		CSR_RESET,
		CSR_GP_CNTRL,
		CSR_HW_REV,
		CSR_EEPROM_REG,
		CSR_EEPROM_GP,
		CSR_OTP_GP_REG,
		CSR_GIO_REG,
		CSR_GP_UCODE_REG,
		CSR_GP_DRIVER_REG,
		CSR_UCODE_DRV_GP1,
		CSR_UCODE_DRV_GP2,
		CSR_LED_REG,
		CSR_DRAM_INT_TBL_REG,
		CSR_GIO_CHICKEN_BITS,
		CSR_ANA_PLL_CFG,
		CSR_HW_REV_WA_REG,
		CSR_DBG_HPET_MEM_REG
	};
	IWL_ERR(trans, "CSR values:\n");
	IWL_ERR(trans, "(2nd byte of CSR_INT_COALESCING is "
		"CSR_INT_PERIODIC_REG)\n");
	for (i = 0; i <  ARRAY_SIZE(csr_tbl); i++) {
		IWL_ERR(trans, "  %25s: 0X%08x\n",
			get_csr_string(csr_tbl[i]),
			iwl_read32(trans, csr_tbl[i]));
	}
}

#ifdef CONFIG_IWLWIFI_DEBUGFS
/* create and remove of files */
#define DEBUGFS_ADD_FILE(name, parent, mode) do {			\
	if (!debugfs_create_file(#name, mode, parent, trans,		\
				 &iwl_dbgfs_##name##_ops))		\
		return -ENOMEM;						\
} while (0)

/* file operation */
#define DEBUGFS_READ_FUNC(name)                                         \
static ssize_t iwl_dbgfs_##name##_read(struct file *file,               \
					char __user *user_buf,          \
					size_t count, loff_t *ppos);

#define DEBUGFS_WRITE_FUNC(name)                                        \
static ssize_t iwl_dbgfs_##name##_write(struct file *file,              \
					const char __user *user_buf,    \
					size_t count, loff_t *ppos);


#define DEBUGFS_READ_FILE_OPS(name)					\
	DEBUGFS_READ_FUNC(name);					\
static const struct file_operations iwl_dbgfs_##name##_ops = {		\
	.read = iwl_dbgfs_##name##_read,				\
	.open = simple_open,						\
	.llseek = generic_file_llseek,					\
};

#define DEBUGFS_WRITE_FILE_OPS(name)                                    \
	DEBUGFS_WRITE_FUNC(name);                                       \
static const struct file_operations iwl_dbgfs_##name##_ops = {          \
	.write = iwl_dbgfs_##name##_write,                              \
	.open = simple_open,						\
	.llseek = generic_file_llseek,					\
};

#define DEBUGFS_READ_WRITE_FILE_OPS(name)				\
	DEBUGFS_READ_FUNC(name);					\
	DEBUGFS_WRITE_FUNC(name);					\
static const struct file_operations iwl_dbgfs_##name##_ops = {		\
	.write = iwl_dbgfs_##name##_write,				\
	.read = iwl_dbgfs_##name##_read,				\
	.open = simple_open,						\
	.llseek = generic_file_llseek,					\
};

static ssize_t iwl_dbgfs_tx_queue_read(struct file *file,
				       char __user *user_buf,
				       size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_tx_queue *txq;
	struct iwl_queue *q;
	char *buf;
	int pos = 0;
	int cnt;
	int ret;
	size_t bufsz;

	bufsz = sizeof(char) * 64 * trans->cfg->base_params->num_of_queues;

	if (!trans_pcie->txq)
		return -EAGAIN;

	buf = kzalloc(bufsz, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	for (cnt = 0; cnt < trans->cfg->base_params->num_of_queues; cnt++) {
		txq = &trans_pcie->txq[cnt];
		q = &txq->q;
		pos += scnprintf(buf + pos, bufsz - pos,
				"hwq %.2d: read=%u write=%u use=%d stop=%d\n",
				cnt, q->read_ptr, q->write_ptr,
				!!test_bit(cnt, trans_pcie->queue_used),
				!!test_bit(cnt, trans_pcie->queue_stopped));
	}
	ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos);
	kfree(buf);
	return ret;
}

static ssize_t iwl_dbgfs_rx_queue_read(struct file *file,
				       char __user *user_buf,
				       size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
	char buf[256];
	int pos = 0;
	const size_t bufsz = sizeof(buf);

	pos += scnprintf(buf + pos, bufsz - pos, "read: %u\n",
						rxq->read);
	pos += scnprintf(buf + pos, bufsz - pos, "write: %u\n",
						rxq->write);
	pos += scnprintf(buf + pos, bufsz - pos, "free_count: %u\n",
						rxq->free_count);
	if (rxq->rb_stts) {
		pos += scnprintf(buf + pos, bufsz - pos, "closed_rb_num: %u\n",
			 le16_to_cpu(rxq->rb_stts->closed_rb_num) &  0x0FFF);
	} else {
		pos += scnprintf(buf + pos, bufsz - pos,
					"closed_rb_num: Not Allocated\n");
	}
	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
}

static ssize_t iwl_dbgfs_interrupt_read(struct file *file,
					char __user *user_buf,
					size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;

	int pos = 0;
	char *buf;
	int bufsz = 24 * 64; /* 24 items * 64 char per item */
	ssize_t ret;

	buf = kzalloc(bufsz, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	pos += scnprintf(buf + pos, bufsz - pos,
			"Interrupt Statistics Report:\n");

	pos += scnprintf(buf + pos, bufsz - pos, "HW Error:\t\t\t %u\n",
		isr_stats->hw);
	pos += scnprintf(buf + pos, bufsz - pos, "SW Error:\t\t\t %u\n",
		isr_stats->sw);
	if (isr_stats->sw || isr_stats->hw) {
		pos += scnprintf(buf + pos, bufsz - pos,
			"\tLast Restarting Code:  0x%X\n",
			isr_stats->err_code);
	}
#ifdef CONFIG_IWLWIFI_DEBUG
	pos += scnprintf(buf + pos, bufsz - pos, "Frame transmitted:\t\t %u\n",
		isr_stats->sch);
	pos += scnprintf(buf + pos, bufsz - pos, "Alive interrupt:\t\t %u\n",
		isr_stats->alive);
#endif
	pos += scnprintf(buf + pos, bufsz - pos,
		"HW RF KILL switch toggled:\t %u\n", isr_stats->rfkill);

	pos += scnprintf(buf + pos, bufsz - pos, "CT KILL:\t\t\t %u\n",
		isr_stats->ctkill);

	pos += scnprintf(buf + pos, bufsz - pos, "Wakeup Interrupt:\t\t %u\n",
		isr_stats->wakeup);

	pos += scnprintf(buf + pos, bufsz - pos,
		"Rx command responses:\t\t %u\n", isr_stats->rx);

	pos += scnprintf(buf + pos, bufsz - pos, "Tx/FH interrupt:\t\t %u\n",
		isr_stats->tx);

	pos += scnprintf(buf + pos, bufsz - pos, "Unexpected INTA:\t\t %u\n",
		isr_stats->unhandled);

	ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos);
	kfree(buf);
	return ret;
}

static ssize_t iwl_dbgfs_interrupt_write(struct file *file,
					 const char __user *user_buf,
					 size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;
	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;

	char buf[8];
	int buf_size;
	u32 reset_flag;

	memset(buf, 0, sizeof(buf));
	buf_size = min(count, sizeof(buf) -  1);
	if (copy_from_user(buf, user_buf, buf_size))
		return -EFAULT;
	if (sscanf(buf, "%x", &reset_flag) != 1)
		return -EFAULT;
	if (reset_flag == 0)
		memset(isr_stats, 0, sizeof(*isr_stats));

	return count;
}

static ssize_t iwl_dbgfs_csr_write(struct file *file,
				   const char __user *user_buf,
				   size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;
	char buf[8];
	int buf_size;
	int csr;

	memset(buf, 0, sizeof(buf));
	buf_size = min(count, sizeof(buf) -  1);
	if (copy_from_user(buf, user_buf, buf_size))
		return -EFAULT;
	if (sscanf(buf, "%d", &csr) != 1)
		return -EFAULT;

	iwl_dump_csr(trans);

	return count;
}

static ssize_t iwl_dbgfs_fh_reg_read(struct file *file,
				     char __user *user_buf,
				     size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;
	char *buf = NULL;
	int pos = 0;
	ssize_t ret = -EFAULT;

	ret = pos = iwl_dump_fh(trans, &buf);
	if (buf) {
		ret = simple_read_from_buffer(user_buf,
					      count, ppos, buf, pos);
		kfree(buf);
	}

	return ret;
}

static ssize_t iwl_dbgfs_fw_restart_write(struct file *file,
					  const char __user *user_buf,
					  size_t count, loff_t *ppos)
{
	struct iwl_trans *trans = file->private_data;

	if (!trans->op_mode)
		return -EAGAIN;

	local_bh_disable();
	iwl_op_mode_nic_error(trans->op_mode);
	local_bh_enable();

	return count;
}

DEBUGFS_READ_WRITE_FILE_OPS(interrupt);
DEBUGFS_READ_FILE_OPS(fh_reg);
DEBUGFS_READ_FILE_OPS(rx_queue);
DEBUGFS_READ_FILE_OPS(tx_queue);
DEBUGFS_WRITE_FILE_OPS(csr);
DEBUGFS_WRITE_FILE_OPS(fw_restart);

/*
 * Create the debugfs files and directories
 *
 */
static int iwl_trans_pcie_dbgfs_register(struct iwl_trans *trans,
					 struct dentry *dir)
{
	DEBUGFS_ADD_FILE(rx_queue, dir, S_IRUSR);
	DEBUGFS_ADD_FILE(tx_queue, dir, S_IRUSR);
	DEBUGFS_ADD_FILE(interrupt, dir, S_IWUSR | S_IRUSR);
	DEBUGFS_ADD_FILE(csr, dir, S_IWUSR);
	DEBUGFS_ADD_FILE(fh_reg, dir, S_IRUSR);
	DEBUGFS_ADD_FILE(fw_restart, dir, S_IWUSR);
	return 0;
}
#else
static int iwl_trans_pcie_dbgfs_register(struct iwl_trans *trans,
					 struct dentry *dir)
{
	return 0;
}
#endif /*CONFIG_IWLWIFI_DEBUGFS */

static const struct iwl_trans_ops trans_ops_pcie = {
	.start_hw = iwl_trans_pcie_start_hw,
	.stop_hw = iwl_trans_pcie_stop_hw,
	.fw_alive = iwl_trans_pcie_fw_alive,
	.start_fw = iwl_trans_pcie_start_fw,
	.stop_device = iwl_trans_pcie_stop_device,

	.wowlan_suspend = iwl_trans_pcie_wowlan_suspend,

	.send_cmd = iwl_trans_pcie_send_cmd,

	.tx = iwl_trans_pcie_tx,
	.reclaim = iwl_trans_pcie_reclaim,

	.txq_disable = iwl_trans_pcie_txq_disable,
	.txq_enable = iwl_trans_pcie_txq_enable,

	.dbgfs_register = iwl_trans_pcie_dbgfs_register,

	.wait_tx_queue_empty = iwl_trans_pcie_wait_tx_queue_empty,

#ifdef CONFIG_PM_SLEEP
	.suspend = iwl_trans_pcie_suspend,
	.resume = iwl_trans_pcie_resume,
#endif
	.write8 = iwl_trans_pcie_write8,
	.write32 = iwl_trans_pcie_write32,
	.read32 = iwl_trans_pcie_read32,
	.configure = iwl_trans_pcie_configure,
	.set_pmi = iwl_trans_pcie_set_pmi,
};

struct iwl_trans *iwl_trans_pcie_alloc(struct pci_dev *pdev,
				       const struct pci_device_id *ent,
				       const struct iwl_cfg *cfg)
{
	struct iwl_trans_pcie *trans_pcie;
	struct iwl_trans *trans;
	u16 pci_cmd;
	int err;

	trans = kzalloc(sizeof(struct iwl_trans) +
			sizeof(struct iwl_trans_pcie), GFP_KERNEL);

	if (WARN_ON(!trans))
		return NULL;

	trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

	trans->ops = &trans_ops_pcie;
	trans->cfg = cfg;
	trans_pcie->trans = trans;
	spin_lock_init(&trans_pcie->irq_lock);
	init_waitqueue_head(&trans_pcie->ucode_write_waitq);

	/* W/A - seems to solve weird behavior. We need to remove this if we
	 * don't want to stay in L1 all the time. This wastes a lot of power */
	pci_disable_link_state(pdev, PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1 |
			       PCIE_LINK_STATE_CLKPM);

	if (pci_enable_device(pdev)) {
		err = -ENODEV;
		goto out_no_pci;
	}

	pci_set_master(pdev);

	err = pci_set_dma_mask(pdev, DMA_BIT_MASK(36));
	if (!err)
		err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(36));
	if (err) {
		err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
		if (!err)
			err = pci_set_consistent_dma_mask(pdev,
							  DMA_BIT_MASK(32));
		/* both attempts failed: */
		if (err) {
			dev_printk(KERN_ERR, &pdev->dev,
				   "No suitable DMA available.\n");
			goto out_pci_disable_device;
		}
	}

	err = pci_request_regions(pdev, DRV_NAME);
	if (err) {
		dev_printk(KERN_ERR, &pdev->dev,
			   "pci_request_regions failed\n");
		goto out_pci_disable_device;
	}

	trans_pcie->hw_base = pci_ioremap_bar(pdev, 0);
	if (!trans_pcie->hw_base) {
		dev_printk(KERN_ERR, &pdev->dev, "pci_ioremap_bar failed\n");
		err = -ENODEV;
		goto out_pci_release_regions;
	}

	dev_printk(KERN_INFO, &pdev->dev,
		   "pci_resource_len = 0x%08llx\n",
		   (unsigned long long) pci_resource_len(pdev, 0));
	dev_printk(KERN_INFO, &pdev->dev,
		   "pci_resource_base = %p\n", trans_pcie->hw_base);

	dev_printk(KERN_INFO, &pdev->dev,
		   "HW Revision ID = 0x%X\n", pdev->revision);

	/* We disable the RETRY_TIMEOUT register (0x41) to keep
	 * PCI Tx retries from interfering with C3 CPU state */
	pci_write_config_byte(pdev, PCI_CFG_RETRY_TIMEOUT, 0x00);

	err = pci_enable_msi(pdev);
	if (err)
		dev_printk(KERN_ERR, &pdev->dev,
			   "pci_enable_msi failed(0X%x)\n", err);

	trans->dev = &pdev->dev;
	trans_pcie->irq = pdev->irq;
	trans_pcie->pci_dev = pdev;
	trans->hw_rev = iwl_read32(trans, CSR_HW_REV);
	trans->hw_id = (pdev->device << 16) + pdev->subsystem_device;
	snprintf(trans->hw_id_str, sizeof(trans->hw_id_str),
		 "PCI ID: 0x%04X:0x%04X", pdev->device, pdev->subsystem_device);

	/* TODO: Move this away, not needed if not MSI */
	/* enable rfkill interrupt: hw bug w/a */
	pci_read_config_word(pdev, PCI_COMMAND, &pci_cmd);
	if (pci_cmd & PCI_COMMAND_INTX_DISABLE) {
		pci_cmd &= ~PCI_COMMAND_INTX_DISABLE;
		pci_write_config_word(pdev, PCI_COMMAND, pci_cmd);
	}

	/* Initialize the wait queue for commands */
	init_waitqueue_head(&trans->wait_command_queue);
	spin_lock_init(&trans->reg_lock);

	snprintf(trans->dev_cmd_pool_name, sizeof(trans->dev_cmd_pool_name),
		 "iwl_cmd_pool:%s", dev_name(trans->dev));

	trans->dev_cmd_headroom = 0;
	trans->dev_cmd_pool =
		kmem_cache_create(trans->dev_cmd_pool_name,
				  sizeof(struct iwl_device_cmd)
				  + trans->dev_cmd_headroom,
				  sizeof(void *),
				  SLAB_HWCACHE_ALIGN,
				  NULL);

	if (!trans->dev_cmd_pool)
		goto out_pci_disable_msi;

	return trans;

out_pci_disable_msi:
	pci_disable_msi(pdev);
out_pci_release_regions:
	pci_release_regions(pdev);
out_pci_disable_device:
	pci_disable_device(pdev);
out_no_pci:
	kfree(trans);
	return NULL;
}