iwlwifi: move PCIe into subdirectory

Structure the code a bit more and move all PCIe code
including the hardware configuration files into a
PCIe specific subdirectory.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/pcie/rx.c b/drivers/net/wireless/iwlwifi/pcie/rx.c
new file mode 100644
index 0000000..d6860c0
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/pcie/rx.c
@@ -0,0 +1,1058 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2003 - 2012 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/sched.h>
+#include <linux/wait.h>
+#include <linux/gfp.h>
+
+#include "iwl-prph.h"
+#include "iwl-io.h"
+#include "internal.h"
+#include "iwl-op-mode.h"
+
+#ifdef CONFIG_IWLWIFI_IDI
+#include "iwl-amfh.h"
+#endif
+
+/******************************************************************************
+ *
+ * RX path functions
+ *
+ ******************************************************************************/
+
+/*
+ * Rx theory of operation
+ *
+ * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
+ * each of which point to Receive Buffers to be filled by the NIC.  These get
+ * used not only for Rx frames, but for any command response or notification
+ * from the NIC.  The driver and NIC manage the Rx buffers by means
+ * of indexes into the circular buffer.
+ *
+ * Rx Queue Indexes
+ * The host/firmware share two index registers for managing the Rx buffers.
+ *
+ * The READ index maps to the first position that the firmware may be writing
+ * to -- the driver can read up to (but not including) this position and get
+ * good data.
+ * The READ index is managed by the firmware once the card is enabled.
+ *
+ * The WRITE index maps to the last position the driver has read from -- the
+ * position preceding WRITE is the last slot the firmware can place a packet.
+ *
+ * The queue is empty (no good data) if WRITE = READ - 1, and is full if
+ * WRITE = READ.
+ *
+ * During initialization, the host sets up the READ queue position to the first
+ * INDEX position, and WRITE to the last (READ - 1 wrapped)
+ *
+ * When the firmware places a packet in a buffer, it will advance the READ index
+ * and fire the RX interrupt.  The driver can then query the READ index and
+ * process as many packets as possible, moving the WRITE index forward as it
+ * resets the Rx queue buffers with new memory.
+ *
+ * The management in the driver is as follows:
+ * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free.  When
+ *   iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
+ *   to replenish the iwl->rxq->rx_free.
+ * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the
+ *   iwl->rxq is replenished and the READ INDEX is updated (updating the
+ *   'processed' and 'read' driver indexes as well)
+ * + A received packet is processed and handed to the kernel network stack,
+ *   detached from the iwl->rxq.  The driver 'processed' index is updated.
+ * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
+ *   list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
+ *   INDEX is not incremented and iwl->status(RX_STALLED) is set.  If there
+ *   were enough free buffers and RX_STALLED is set it is cleared.
+ *
+ *
+ * Driver sequence:
+ *
+ * iwl_rx_queue_alloc()   Allocates rx_free
+ * iwl_rx_replenish()     Replenishes rx_free list from rx_used, and calls
+ *                            iwl_rx_queue_restock
+ * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx
+ *                            queue, updates firmware pointers, and updates
+ *                            the WRITE index.  If insufficient rx_free buffers
+ *                            are available, schedules iwl_rx_replenish
+ *
+ * -- enable interrupts --
+ * ISR - iwl_rx()         Detach iwl_rx_mem_buffers from pool up to the
+ *                            READ INDEX, detaching the SKB from the pool.
+ *                            Moves the packet buffer from queue to rx_used.
+ *                            Calls iwl_rx_queue_restock to refill any empty
+ *                            slots.
+ * ...
+ *
+ */
+
+/**
+ * iwl_rx_queue_space - Return number of free slots available in queue.
+ */
+static int iwl_rx_queue_space(const struct iwl_rx_queue *q)
+{
+	int s = q->read - q->write;
+	if (s <= 0)
+		s += RX_QUEUE_SIZE;
+	/* keep some buffer to not confuse full and empty queue */
+	s -= 2;
+	if (s < 0)
+		s = 0;
+	return s;
+}
+
+/**
+ * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
+ */
+void iwl_rx_queue_update_write_ptr(struct iwl_trans *trans,
+				   struct iwl_rx_queue *q)
+{
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(&q->lock, flags);
+
+	if (q->need_update == 0)
+		goto exit_unlock;
+
+	if (trans->cfg->base_params->shadow_reg_enable) {
+		/* shadow register enabled */
+		/* Device expects a multiple of 8 */
+		q->write_actual = (q->write & ~0x7);
+		iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, q->write_actual);
+	} else {
+		struct iwl_trans_pcie *trans_pcie =
+			IWL_TRANS_GET_PCIE_TRANS(trans);
+
+		/* If power-saving is in use, make sure device is awake */
+		if (test_bit(STATUS_TPOWER_PMI, &trans_pcie->status)) {
+			reg = iwl_read32(trans, CSR_UCODE_DRV_GP1);
+
+			if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
+				IWL_DEBUG_INFO(trans,
+					"Rx queue requesting wakeup,"
+					" GP1 = 0x%x\n", reg);
+				iwl_set_bit(trans, CSR_GP_CNTRL,
+					CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+				goto exit_unlock;
+			}
+
+			q->write_actual = (q->write & ~0x7);
+			iwl_write_direct32(trans, FH_RSCSR_CHNL0_WPTR,
+					q->write_actual);
+
+		/* Else device is assumed to be awake */
+		} else {
+			/* Device expects a multiple of 8 */
+			q->write_actual = (q->write & ~0x7);
+			iwl_write_direct32(trans, FH_RSCSR_CHNL0_WPTR,
+				q->write_actual);
+		}
+	}
+	q->need_update = 0;
+
+ exit_unlock:
+	spin_unlock_irqrestore(&q->lock, flags);
+}
+
+/**
+ * iwlagn_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
+ */
+static inline __le32 iwlagn_dma_addr2rbd_ptr(dma_addr_t dma_addr)
+{
+	return cpu_to_le32((u32)(dma_addr >> 8));
+}
+
+/**
+ * iwlagn_rx_queue_restock - refill RX queue from pre-allocated pool
+ *
+ * If there are slots in the RX queue that need to be restocked,
+ * and we have free pre-allocated buffers, fill the ranks as much
+ * as we can, pulling from rx_free.
+ *
+ * This moves the 'write' index forward to catch up with 'processed', and
+ * also updates the memory address in the firmware to reference the new
+ * target buffer.
+ */
+static void iwlagn_rx_queue_restock(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 list_head *element;
+	struct iwl_rx_mem_buffer *rxb;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rxq->lock, flags);
+	while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
+		/* The overwritten rxb must be a used one */
+		rxb = rxq->queue[rxq->write];
+		BUG_ON(rxb && rxb->page);
+
+		/* Get next free Rx buffer, remove from free list */
+		element = rxq->rx_free.next;
+		rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
+		list_del(element);
+
+		/* Point to Rx buffer via next RBD in circular buffer */
+		rxq->bd[rxq->write] = iwlagn_dma_addr2rbd_ptr(rxb->page_dma);
+		rxq->queue[rxq->write] = rxb;
+		rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
+		rxq->free_count--;
+	}
+	spin_unlock_irqrestore(&rxq->lock, flags);
+	/* If the pre-allocated buffer pool is dropping low, schedule to
+	 * refill it */
+	if (rxq->free_count <= RX_LOW_WATERMARK)
+		schedule_work(&trans_pcie->rx_replenish);
+
+
+	/* If we've added more space for the firmware to place data, tell it.
+	 * Increment device's write pointer in multiples of 8. */
+	if (rxq->write_actual != (rxq->write & ~0x7)) {
+		spin_lock_irqsave(&rxq->lock, flags);
+		rxq->need_update = 1;
+		spin_unlock_irqrestore(&rxq->lock, flags);
+		iwl_rx_queue_update_write_ptr(trans, rxq);
+	}
+}
+
+/**
+ * iwlagn_rx_replenish - Move all used packet from rx_used to rx_free
+ *
+ * When moving to rx_free an SKB is allocated for the slot.
+ *
+ * Also restock the Rx queue via iwl_rx_queue_restock.
+ * This is called as a scheduled work item (except for during initialization)
+ */
+static void iwlagn_rx_allocate(struct iwl_trans *trans, gfp_t priority)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
+	struct list_head *element;
+	struct iwl_rx_mem_buffer *rxb;
+	struct page *page;
+	unsigned long flags;
+	gfp_t gfp_mask = priority;
+
+	while (1) {
+		spin_lock_irqsave(&rxq->lock, flags);
+		if (list_empty(&rxq->rx_used)) {
+			spin_unlock_irqrestore(&rxq->lock, flags);
+			return;
+		}
+		spin_unlock_irqrestore(&rxq->lock, flags);
+
+		if (rxq->free_count > RX_LOW_WATERMARK)
+			gfp_mask |= __GFP_NOWARN;
+
+		if (trans_pcie->rx_page_order > 0)
+			gfp_mask |= __GFP_COMP;
+
+		/* Alloc a new receive buffer */
+		page = alloc_pages(gfp_mask, trans_pcie->rx_page_order);
+		if (!page) {
+			if (net_ratelimit())
+				IWL_DEBUG_INFO(trans, "alloc_pages failed, "
+					   "order: %d\n",
+					   trans_pcie->rx_page_order);
+
+			if ((rxq->free_count <= RX_LOW_WATERMARK) &&
+			    net_ratelimit())
+				IWL_CRIT(trans, "Failed to alloc_pages with %s."
+					 "Only %u free buffers remaining.\n",
+					 priority == GFP_ATOMIC ?
+					 "GFP_ATOMIC" : "GFP_KERNEL",
+					 rxq->free_count);
+			/* We don't reschedule replenish work here -- we will
+			 * call the restock method and if it still needs
+			 * more buffers it will schedule replenish */
+			return;
+		}
+
+		spin_lock_irqsave(&rxq->lock, flags);
+
+		if (list_empty(&rxq->rx_used)) {
+			spin_unlock_irqrestore(&rxq->lock, flags);
+			__free_pages(page, trans_pcie->rx_page_order);
+			return;
+		}
+		element = rxq->rx_used.next;
+		rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
+		list_del(element);
+
+		spin_unlock_irqrestore(&rxq->lock, flags);
+
+		BUG_ON(rxb->page);
+		rxb->page = page;
+		/* Get physical address of the RB */
+		rxb->page_dma =
+			dma_map_page(trans->dev, page, 0,
+				     PAGE_SIZE << trans_pcie->rx_page_order,
+				     DMA_FROM_DEVICE);
+		/* dma address must be no more than 36 bits */
+		BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
+		/* and also 256 byte aligned! */
+		BUG_ON(rxb->page_dma & DMA_BIT_MASK(8));
+
+		spin_lock_irqsave(&rxq->lock, flags);
+
+		list_add_tail(&rxb->list, &rxq->rx_free);
+		rxq->free_count++;
+
+		spin_unlock_irqrestore(&rxq->lock, flags);
+	}
+}
+
+void iwlagn_rx_replenish(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	unsigned long flags;
+
+	iwlagn_rx_allocate(trans, GFP_KERNEL);
+
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+	iwlagn_rx_queue_restock(trans);
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+}
+
+static void iwlagn_rx_replenish_now(struct iwl_trans *trans)
+{
+	iwlagn_rx_allocate(trans, GFP_ATOMIC);
+
+	iwlagn_rx_queue_restock(trans);
+}
+
+void iwl_bg_rx_replenish(struct work_struct *data)
+{
+	struct iwl_trans_pcie *trans_pcie =
+	    container_of(data, struct iwl_trans_pcie, rx_replenish);
+
+	iwlagn_rx_replenish(trans_pcie->trans);
+}
+
+static void iwl_rx_handle_rxbuf(struct iwl_trans *trans,
+				struct iwl_rx_mem_buffer *rxb)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
+	struct iwl_tx_queue *txq = &trans_pcie->txq[trans_pcie->cmd_queue];
+	unsigned long flags;
+	bool page_stolen = false;
+	int max_len = PAGE_SIZE << trans_pcie->rx_page_order;
+	u32 offset = 0;
+
+	if (WARN_ON(!rxb))
+		return;
+
+	dma_unmap_page(trans->dev, rxb->page_dma, max_len, DMA_FROM_DEVICE);
+
+	while (offset + sizeof(u32) + sizeof(struct iwl_cmd_header) < max_len) {
+		struct iwl_rx_packet *pkt;
+		struct iwl_device_cmd *cmd;
+		u16 sequence;
+		bool reclaim;
+		int index, cmd_index, err, len;
+		struct iwl_rx_cmd_buffer rxcb = {
+			._offset = offset,
+			._page = rxb->page,
+			._page_stolen = false,
+			.truesize = max_len,
+		};
+
+		pkt = rxb_addr(&rxcb);
+
+		if (pkt->len_n_flags == cpu_to_le32(FH_RSCSR_FRAME_INVALID))
+			break;
+
+		IWL_DEBUG_RX(trans, "cmd at offset %d: %s (0x%.2x)\n",
+			rxcb._offset,
+			trans_pcie_get_cmd_string(trans_pcie, pkt->hdr.cmd),
+			pkt->hdr.cmd);
+
+		len = le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK;
+		len += sizeof(u32); /* account for status word */
+		trace_iwlwifi_dev_rx(trans->dev, pkt, len);
+
+		/* Reclaim a command buffer only if this packet is a response
+		 *   to a (driver-originated) command.
+		 * If the packet (e.g. Rx frame) originated from uCode,
+		 *   there is no command buffer to reclaim.
+		 * Ucode should set SEQ_RX_FRAME bit if ucode-originated,
+		 *   but apparently a few don't get set; catch them here. */
+		reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME);
+		if (reclaim) {
+			int i;
+
+			for (i = 0; i < trans_pcie->n_no_reclaim_cmds; i++) {
+				if (trans_pcie->no_reclaim_cmds[i] ==
+							pkt->hdr.cmd) {
+					reclaim = false;
+					break;
+				}
+			}
+		}
+
+		sequence = le16_to_cpu(pkt->hdr.sequence);
+		index = SEQ_TO_INDEX(sequence);
+		cmd_index = get_cmd_index(&txq->q, index);
+
+		if (reclaim)
+			cmd = txq->entries[cmd_index].cmd;
+		else
+			cmd = NULL;
+
+		err = iwl_op_mode_rx(trans->op_mode, &rxcb, cmd);
+
+		/*
+		 * After here, we should always check rxcb._page_stolen,
+		 * if it is true then one of the handlers took the page.
+		 */
+
+		if (reclaim) {
+			/* Invoke any callbacks, transfer the buffer to caller,
+			 * and fire off the (possibly) blocking
+			 * iwl_trans_send_cmd()
+			 * as we reclaim the driver command queue */
+			if (!rxcb._page_stolen)
+				iwl_tx_cmd_complete(trans, &rxcb, err);
+			else
+				IWL_WARN(trans, "Claim null rxb?\n");
+		}
+
+		page_stolen |= rxcb._page_stolen;
+		offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
+	}
+
+	/* page was stolen from us -- free our reference */
+	if (page_stolen) {
+		__free_pages(rxb->page, trans_pcie->rx_page_order);
+		rxb->page = NULL;
+	}
+
+	/* Reuse the page if possible. For notification packets and
+	 * SKBs that fail to Rx correctly, add them back into the
+	 * rx_free list for reuse later. */
+	spin_lock_irqsave(&rxq->lock, flags);
+	if (rxb->page != NULL) {
+		rxb->page_dma =
+			dma_map_page(trans->dev, rxb->page, 0,
+				     PAGE_SIZE << trans_pcie->rx_page_order,
+				     DMA_FROM_DEVICE);
+		list_add_tail(&rxb->list, &rxq->rx_free);
+		rxq->free_count++;
+	} else
+		list_add_tail(&rxb->list, &rxq->rx_used);
+	spin_unlock_irqrestore(&rxq->lock, flags);
+}
+
+/**
+ * iwl_rx_handle - Main entry function for receiving responses from uCode
+ *
+ * Uses the priv->rx_handlers callback function array to invoke
+ * the appropriate handlers, including command responses,
+ * frame-received notifications, and other notifications.
+ */
+static void iwl_rx_handle(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	struct iwl_rx_queue *rxq = &trans_pcie->rxq;
+	u32 r, i;
+	u8 fill_rx = 0;
+	u32 count = 8;
+	int total_empty;
+
+	/* uCode's read index (stored in shared DRAM) indicates the last Rx
+	 * buffer that the driver may process (last buffer filled by ucode). */
+	r = le16_to_cpu(rxq->rb_stts->closed_rb_num) &  0x0FFF;
+	i = rxq->read;
+
+	/* Rx interrupt, but nothing sent from uCode */
+	if (i == r)
+		IWL_DEBUG_RX(trans, "HW = SW = %d\n", r);
+
+	/* calculate total frames need to be restock after handling RX */
+	total_empty = r - rxq->write_actual;
+	if (total_empty < 0)
+		total_empty += RX_QUEUE_SIZE;
+
+	if (total_empty > (RX_QUEUE_SIZE / 2))
+		fill_rx = 1;
+
+	while (i != r) {
+		struct iwl_rx_mem_buffer *rxb;
+
+		rxb = rxq->queue[i];
+		rxq->queue[i] = NULL;
+
+		IWL_DEBUG_RX(trans, "rxbuf: HW = %d, SW = %d (%p)\n",
+			     r, i, rxb);
+		iwl_rx_handle_rxbuf(trans, rxb);
+
+		i = (i + 1) & RX_QUEUE_MASK;
+		/* If there are a lot of unused frames,
+		 * restock the Rx queue so ucode wont assert. */
+		if (fill_rx) {
+			count++;
+			if (count >= 8) {
+				rxq->read = i;
+				iwlagn_rx_replenish_now(trans);
+				count = 0;
+			}
+		}
+	}
+
+	/* Backtrack one entry */
+	rxq->read = i;
+	if (fill_rx)
+		iwlagn_rx_replenish_now(trans);
+	else
+		iwlagn_rx_queue_restock(trans);
+}
+
+/**
+ * iwl_irq_handle_error - called for HW or SW error interrupt from card
+ */
+static void iwl_irq_handle_error(struct iwl_trans *trans)
+{
+	/* W/A for WiFi/WiMAX coex and WiMAX own the RF */
+	if (trans->cfg->internal_wimax_coex &&
+	    (!(iwl_read_prph(trans, APMG_CLK_CTRL_REG) &
+			     APMS_CLK_VAL_MRB_FUNC_MODE) ||
+	     (iwl_read_prph(trans, APMG_PS_CTRL_REG) &
+			    APMG_PS_CTRL_VAL_RESET_REQ))) {
+		struct iwl_trans_pcie *trans_pcie =
+			IWL_TRANS_GET_PCIE_TRANS(trans);
+
+		clear_bit(STATUS_HCMD_ACTIVE, &trans_pcie->status);
+		iwl_op_mode_wimax_active(trans->op_mode);
+		wake_up(&trans->wait_command_queue);
+		return;
+	}
+
+	iwl_dump_csr(trans);
+	iwl_dump_fh(trans, NULL, false);
+
+	iwl_op_mode_nic_error(trans->op_mode);
+}
+
+/* tasklet for iwlagn interrupt */
+void iwl_irq_tasklet(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
+	u32 inta = 0;
+	u32 handled = 0;
+	unsigned long flags;
+	u32 i;
+#ifdef CONFIG_IWLWIFI_DEBUG
+	u32 inta_mask;
+#endif
+
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+
+	/* Ack/clear/reset pending uCode interrupts.
+	 * Note:  Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS,
+	 */
+	/* There is a hardware bug in the interrupt mask function that some
+	 * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if
+	 * they are disabled in the CSR_INT_MASK register. Furthermore the
+	 * ICT interrupt handling mechanism has another bug that might cause
+	 * these unmasked interrupts fail to be detected. We workaround the
+	 * hardware bugs here by ACKing all the possible interrupts so that
+	 * interrupt coalescing can still be achieved.
+	 */
+	iwl_write32(trans, CSR_INT,
+		    trans_pcie->inta | ~trans_pcie->inta_mask);
+
+	inta = trans_pcie->inta;
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+	if (iwl_have_debug_level(IWL_DL_ISR)) {
+		/* just for debug */
+		inta_mask = iwl_read32(trans, CSR_INT_MASK);
+		IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n",
+			      inta, inta_mask);
+	}
+#endif
+
+	/* saved interrupt in inta variable now we can reset trans_pcie->inta */
+	trans_pcie->inta = 0;
+
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+
+	/* Now service all interrupt bits discovered above. */
+	if (inta & CSR_INT_BIT_HW_ERR) {
+		IWL_ERR(trans, "Hardware error detected.  Restarting.\n");
+
+		/* Tell the device to stop sending interrupts */
+		iwl_disable_interrupts(trans);
+
+		isr_stats->hw++;
+		iwl_irq_handle_error(trans);
+
+		handled |= CSR_INT_BIT_HW_ERR;
+
+		return;
+	}
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+	if (iwl_have_debug_level(IWL_DL_ISR)) {
+		/* NIC fires this, but we don't use it, redundant with WAKEUP */
+		if (inta & CSR_INT_BIT_SCD) {
+			IWL_DEBUG_ISR(trans, "Scheduler finished to transmit "
+				      "the frame/frames.\n");
+			isr_stats->sch++;
+		}
+
+		/* Alive notification via Rx interrupt will do the real work */
+		if (inta & CSR_INT_BIT_ALIVE) {
+			IWL_DEBUG_ISR(trans, "Alive interrupt\n");
+			isr_stats->alive++;
+		}
+	}
+#endif
+	/* Safely ignore these bits for debug checks below */
+	inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE);
+
+	/* HW RF KILL switch toggled */
+	if (inta & CSR_INT_BIT_RF_KILL) {
+		bool hw_rfkill;
+
+		hw_rfkill = iwl_is_rfkill_set(trans);
+		IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
+			 hw_rfkill ? "disable radio" : "enable radio");
+
+		isr_stats->rfkill++;
+
+		iwl_op_mode_hw_rf_kill(trans->op_mode, hw_rfkill);
+
+		handled |= CSR_INT_BIT_RF_KILL;
+	}
+
+	/* Chip got too hot and stopped itself */
+	if (inta & CSR_INT_BIT_CT_KILL) {
+		IWL_ERR(trans, "Microcode CT kill error detected.\n");
+		isr_stats->ctkill++;
+		handled |= CSR_INT_BIT_CT_KILL;
+	}
+
+	/* Error detected by uCode */
+	if (inta & CSR_INT_BIT_SW_ERR) {
+		IWL_ERR(trans, "Microcode SW error detected. "
+			" Restarting 0x%X.\n", inta);
+		isr_stats->sw++;
+		iwl_irq_handle_error(trans);
+		handled |= CSR_INT_BIT_SW_ERR;
+	}
+
+	/* uCode wakes up after power-down sleep */
+	if (inta & CSR_INT_BIT_WAKEUP) {
+		IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
+		iwl_rx_queue_update_write_ptr(trans, &trans_pcie->rxq);
+		for (i = 0; i < trans->cfg->base_params->num_of_queues; i++)
+			iwl_txq_update_write_ptr(trans,
+						 &trans_pcie->txq[i]);
+
+		isr_stats->wakeup++;
+
+		handled |= CSR_INT_BIT_WAKEUP;
+	}
+
+	/* All uCode command responses, including Tx command responses,
+	 * Rx "responses" (frame-received notification), and other
+	 * notifications from uCode come through here*/
+	if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX |
+		    CSR_INT_BIT_RX_PERIODIC)) {
+		IWL_DEBUG_ISR(trans, "Rx interrupt\n");
+		if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) {
+			handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX);
+			iwl_write32(trans, CSR_FH_INT_STATUS,
+					CSR_FH_INT_RX_MASK);
+		}
+		if (inta & CSR_INT_BIT_RX_PERIODIC) {
+			handled |= CSR_INT_BIT_RX_PERIODIC;
+			iwl_write32(trans,
+				CSR_INT, CSR_INT_BIT_RX_PERIODIC);
+		}
+		/* Sending RX interrupt require many steps to be done in the
+		 * the device:
+		 * 1- write interrupt to current index in ICT table.
+		 * 2- dma RX frame.
+		 * 3- update RX shared data to indicate last write index.
+		 * 4- send interrupt.
+		 * This could lead to RX race, driver could receive RX interrupt
+		 * but the shared data changes does not reflect this;
+		 * periodic interrupt will detect any dangling Rx activity.
+		 */
+
+		/* Disable periodic interrupt; we use it as just a one-shot. */
+		iwl_write8(trans, CSR_INT_PERIODIC_REG,
+			    CSR_INT_PERIODIC_DIS);
+#ifdef CONFIG_IWLWIFI_IDI
+		iwl_amfh_rx_handler();
+#else
+		iwl_rx_handle(trans);
+#endif
+		/*
+		 * Enable periodic interrupt in 8 msec only if we received
+		 * real RX interrupt (instead of just periodic int), to catch
+		 * any dangling Rx interrupt.  If it was just the periodic
+		 * interrupt, there was no dangling Rx activity, and no need
+		 * to extend the periodic interrupt; one-shot is enough.
+		 */
+		if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX))
+			iwl_write8(trans, CSR_INT_PERIODIC_REG,
+				   CSR_INT_PERIODIC_ENA);
+
+		isr_stats->rx++;
+	}
+
+	/* This "Tx" DMA channel is used only for loading uCode */
+	if (inta & CSR_INT_BIT_FH_TX) {
+		iwl_write32(trans, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
+		IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
+		isr_stats->tx++;
+		handled |= CSR_INT_BIT_FH_TX;
+		/* Wake up uCode load routine, now that load is complete */
+		trans_pcie->ucode_write_complete = true;
+		wake_up(&trans_pcie->ucode_write_waitq);
+	}
+
+	if (inta & ~handled) {
+		IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
+		isr_stats->unhandled++;
+	}
+
+	if (inta & ~(trans_pcie->inta_mask)) {
+		IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n",
+			 inta & ~trans_pcie->inta_mask);
+	}
+
+	/* Re-enable all interrupts */
+	/* only Re-enable if disabled by irq */
+	if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status))
+		iwl_enable_interrupts(trans);
+	/* Re-enable RF_KILL if it occurred */
+	else if (handled & CSR_INT_BIT_RF_KILL)
+		iwl_enable_rfkill_int(trans);
+}
+
+/******************************************************************************
+ *
+ * ICT functions
+ *
+ ******************************************************************************/
+
+/* a device (PCI-E) page is 4096 bytes long */
+#define ICT_SHIFT	12
+#define ICT_SIZE	(1 << ICT_SHIFT)
+#define ICT_COUNT	(ICT_SIZE / sizeof(u32))
+
+/* Free dram table */
+void iwl_free_isr_ict(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+
+	if (trans_pcie->ict_tbl) {
+		dma_free_coherent(trans->dev, ICT_SIZE,
+				  trans_pcie->ict_tbl,
+				  trans_pcie->ict_tbl_dma);
+		trans_pcie->ict_tbl = NULL;
+		trans_pcie->ict_tbl_dma = 0;
+	}
+}
+
+
+/*
+ * allocate dram shared table, it is an aligned memory
+ * block of ICT_SIZE.
+ * also reset all data related to ICT table interrupt.
+ */
+int iwl_alloc_isr_ict(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+
+	trans_pcie->ict_tbl =
+		dma_alloc_coherent(trans->dev, ICT_SIZE,
+				   &trans_pcie->ict_tbl_dma,
+				   GFP_KERNEL);
+	if (!trans_pcie->ict_tbl)
+		return -ENOMEM;
+
+	/* just an API sanity check ... it is guaranteed to be aligned */
+	if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) {
+		iwl_free_isr_ict(trans);
+		return -EINVAL;
+	}
+
+	IWL_DEBUG_ISR(trans, "ict dma addr %Lx\n",
+		      (unsigned long long)trans_pcie->ict_tbl_dma);
+
+	IWL_DEBUG_ISR(trans, "ict vir addr %p\n", trans_pcie->ict_tbl);
+
+	/* reset table and index to all 0 */
+	memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
+	trans_pcie->ict_index = 0;
+
+	/* add periodic RX interrupt */
+	trans_pcie->inta_mask |= CSR_INT_BIT_RX_PERIODIC;
+	return 0;
+}
+
+/* Device is going up inform it about using ICT interrupt table,
+ * also we need to tell the driver to start using ICT interrupt.
+ */
+void iwl_reset_ict(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	u32 val;
+	unsigned long flags;
+
+	if (!trans_pcie->ict_tbl)
+		return;
+
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+	iwl_disable_interrupts(trans);
+
+	memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
+
+	val = trans_pcie->ict_tbl_dma >> ICT_SHIFT;
+
+	val |= CSR_DRAM_INT_TBL_ENABLE;
+	val |= CSR_DRAM_INIT_TBL_WRAP_CHECK;
+
+	IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val);
+
+	iwl_write32(trans, CSR_DRAM_INT_TBL_REG, val);
+	trans_pcie->use_ict = true;
+	trans_pcie->ict_index = 0;
+	iwl_write32(trans, CSR_INT, trans_pcie->inta_mask);
+	iwl_enable_interrupts(trans);
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+}
+
+/* Device is going down disable ict interrupt usage */
+void iwl_disable_ict(struct iwl_trans *trans)
+{
+	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	unsigned long flags;
+
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+	trans_pcie->use_ict = false;
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+}
+
+static irqreturn_t iwl_isr(int irq, void *data)
+{
+	struct iwl_trans *trans = data;
+	struct iwl_trans_pcie *trans_pcie;
+	u32 inta, inta_mask;
+	unsigned long flags;
+#ifdef CONFIG_IWLWIFI_DEBUG
+	u32 inta_fh;
+#endif
+	if (!trans)
+		return IRQ_NONE;
+
+	trace_iwlwifi_dev_irq(trans->dev);
+
+	trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+
+	/* Disable (but don't clear!) interrupts here to avoid
+	 *    back-to-back ISRs and sporadic interrupts from our NIC.
+	 * If we have something to service, the tasklet will re-enable ints.
+	 * If we *don't* have something, we'll re-enable before leaving here. */
+	inta_mask = iwl_read32(trans, CSR_INT_MASK);  /* just for debug */
+	iwl_write32(trans, CSR_INT_MASK, 0x00000000);
+
+	/* Discover which interrupts are active/pending */
+	inta = iwl_read32(trans, CSR_INT);
+
+	/* Ignore interrupt if there's nothing in NIC to service.
+	 * This may be due to IRQ shared with another device,
+	 * or due to sporadic interrupts thrown from our NIC. */
+	if (!inta) {
+		IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
+		goto none;
+	}
+
+	if ((inta == 0xFFFFFFFF) || ((inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
+		/* Hardware disappeared. It might have already raised
+		 * an interrupt */
+		IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta);
+		goto unplugged;
+	}
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+	if (iwl_have_debug_level(IWL_DL_ISR)) {
+		inta_fh = iwl_read32(trans, CSR_FH_INT_STATUS);
+		IWL_DEBUG_ISR(trans, "ISR inta 0x%08x, enabled 0x%08x, "
+			      "fh 0x%08x\n", inta, inta_mask, inta_fh);
+	}
+#endif
+
+	trans_pcie->inta |= inta;
+	/* iwl_irq_tasklet() will service interrupts and re-enable them */
+	if (likely(inta))
+		tasklet_schedule(&trans_pcie->irq_tasklet);
+	else if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) &&
+		 !trans_pcie->inta)
+		iwl_enable_interrupts(trans);
+
+ unplugged:
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+	return IRQ_HANDLED;
+
+ none:
+	/* re-enable interrupts here since we don't have anything to service. */
+	/* only Re-enable if disabled by irq  and no schedules tasklet. */
+	if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) &&
+	    !trans_pcie->inta)
+		iwl_enable_interrupts(trans);
+
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+	return IRQ_NONE;
+}
+
+/* interrupt handler using ict table, with this interrupt driver will
+ * stop using INTA register to get device's interrupt, reading this register
+ * is expensive, device will write interrupts in ICT dram table, increment
+ * index then will fire interrupt to driver, driver will OR all ICT table
+ * entries from current index up to table entry with 0 value. the result is
+ * the interrupt we need to service, driver will set the entries back to 0 and
+ * set index.
+ */
+irqreturn_t iwl_isr_ict(int irq, void *data)
+{
+	struct iwl_trans *trans = data;
+	struct iwl_trans_pcie *trans_pcie;
+	u32 inta, inta_mask;
+	u32 val = 0;
+	u32 read;
+	unsigned long flags;
+
+	if (!trans)
+		return IRQ_NONE;
+
+	trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+
+	/* dram interrupt table not set yet,
+	 * use legacy interrupt.
+	 */
+	if (!trans_pcie->use_ict)
+		return iwl_isr(irq, data);
+
+	trace_iwlwifi_dev_irq(trans->dev);
+
+	spin_lock_irqsave(&trans_pcie->irq_lock, flags);
+
+	/* Disable (but don't clear!) interrupts here to avoid
+	 * back-to-back ISRs and sporadic interrupts from our NIC.
+	 * If we have something to service, the tasklet will re-enable ints.
+	 * If we *don't* have something, we'll re-enable before leaving here.
+	 */
+	inta_mask = iwl_read32(trans, CSR_INT_MASK);  /* just for debug */
+	iwl_write32(trans, CSR_INT_MASK, 0x00000000);
+
+
+	/* Ignore interrupt if there's nothing in NIC to service.
+	 * This may be due to IRQ shared with another device,
+	 * or due to sporadic interrupts thrown from our NIC. */
+	read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
+	trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, read);
+	if (!read) {
+		IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
+		goto none;
+	}
+
+	/*
+	 * Collect all entries up to the first 0, starting from ict_index;
+	 * note we already read at ict_index.
+	 */
+	do {
+		val |= read;
+		IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n",
+				trans_pcie->ict_index, read);
+		trans_pcie->ict_tbl[trans_pcie->ict_index] = 0;
+		trans_pcie->ict_index =
+			iwl_queue_inc_wrap(trans_pcie->ict_index, ICT_COUNT);
+
+		read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
+		trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index,
+					   read);
+	} while (read);
+
+	/* We should not get this value, just ignore it. */
+	if (val == 0xffffffff)
+		val = 0;
+
+	/*
+	 * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit
+	 * (bit 15 before shifting it to 31) to clear when using interrupt
+	 * coalescing. fortunately, bits 18 and 19 stay set when this happens
+	 * so we use them to decide on the real state of the Rx bit.
+	 * In order words, bit 15 is set if bit 18 or bit 19 are set.
+	 */
+	if (val & 0xC0000)
+		val |= 0x8000;
+
+	inta = (0xff & val) | ((0xff00 & val) << 16);
+	IWL_DEBUG_ISR(trans, "ISR inta 0x%08x, enabled 0x%08x ict 0x%08x\n",
+		      inta, inta_mask, val);
+
+	inta &= trans_pcie->inta_mask;
+	trans_pcie->inta |= inta;
+
+	/* iwl_irq_tasklet() will service interrupts and re-enable them */
+	if (likely(inta))
+		tasklet_schedule(&trans_pcie->irq_tasklet);
+	else if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) &&
+		 !trans_pcie->inta) {
+		/* Allow interrupt if was disabled by this handler and
+		 * no tasklet was schedules, We should not enable interrupt,
+		 * tasklet will enable it.
+		 */
+		iwl_enable_interrupts(trans);
+	}
+
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+	return IRQ_HANDLED;
+
+ none:
+	/* re-enable interrupts here since we don't have anything to service.
+	 * only Re-enable if disabled by irq.
+	 */
+	if (test_bit(STATUS_INT_ENABLED, &trans_pcie->status) &&
+	    !trans_pcie->inta)
+		iwl_enable_interrupts(trans);
+
+	spin_unlock_irqrestore(&trans_pcie->irq_lock, flags);
+	return IRQ_NONE;
+}