summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c')
-rw-r--r--drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c694
1 files changed, 694 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c b/drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c
new file mode 100644
index 000000000000..046a33f5ca6d
--- /dev/null
+++ b/drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c
@@ -0,0 +1,694 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2003 - 2011 Intel Corporation. All rights reserved.
+ *
+ * Portions of this file are derived from the ipw3945 project, as well
+ * as portions of the ieee80211 subsystem header files.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ * Contact Information:
+ * Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#include "iwl-dev.h"
+#include "iwl-agn.h"
+#include "iwl-core.h"
+#include "iwl-io.h"
+#include "iwl-helpers.h"
+#include "iwl-trans-int-pcie.h"
+
+/******************************************************************************
+ *
+ * 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_priv *priv,
+ 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 (priv->cfg->base_params->shadow_reg_enable) {
+ /* shadow register enabled */
+ /* Device expects a multiple of 8 */
+ q->write_actual = (q->write & ~0x7);
+ iwl_write32(priv, FH_RSCSR_CHNL0_WPTR, q->write_actual);
+ } else {
+ /* If power-saving is in use, make sure device is awake */
+ if (test_bit(STATUS_POWER_PMI, &priv->status)) {
+ reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
+
+ if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
+ IWL_DEBUG_INFO(priv,
+ "Rx queue requesting wakeup,"
+ " GP1 = 0x%x\n", reg);
+ iwl_set_bit(priv, CSR_GP_CNTRL,
+ CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+ goto exit_unlock;
+ }
+
+ q->write_actual = (q->write & ~0x7);
+ iwl_write_direct32(priv, 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(priv, 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(struct iwl_priv *priv,
+ 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_priv *priv)
+{
+ struct iwl_rx_queue *rxq = &priv->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(priv,
+ 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)
+ queue_work(priv->workqueue, &priv->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(priv, 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_priv *priv, gfp_t priority)
+{
+ struct iwl_rx_queue *rxq = &priv->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 (priv->hw_params.rx_page_order > 0)
+ gfp_mask |= __GFP_COMP;
+
+ /* Alloc a new receive buffer */
+ page = alloc_pages(gfp_mask, priv->hw_params.rx_page_order);
+ if (!page) {
+ if (net_ratelimit())
+ IWL_DEBUG_INFO(priv, "alloc_pages failed, "
+ "order: %d\n",
+ priv->hw_params.rx_page_order);
+
+ if ((rxq->free_count <= RX_LOW_WATERMARK) &&
+ net_ratelimit())
+ IWL_CRIT(priv, "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, priv->hw_params.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(priv->bus.dev, page, 0,
+ PAGE_SIZE << priv->hw_params.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_priv *priv)
+{
+ unsigned long flags;
+
+ iwlagn_rx_allocate(priv, GFP_KERNEL);
+
+ spin_lock_irqsave(&priv->lock, flags);
+ iwlagn_rx_queue_restock(priv);
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void iwlagn_rx_replenish_now(struct iwl_priv *priv)
+{
+ iwlagn_rx_allocate(priv, GFP_ATOMIC);
+
+ iwlagn_rx_queue_restock(priv);
+}
+
+void iwl_bg_rx_replenish(struct work_struct *data)
+{
+ struct iwl_priv *priv =
+ container_of(data, struct iwl_priv, rx_replenish);
+
+ if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+ return;
+
+ mutex_lock(&priv->mutex);
+ iwlagn_rx_replenish(priv);
+ mutex_unlock(&priv->mutex);
+}
+
+/**
+ * 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_priv *priv)
+{
+ struct iwl_rx_mem_buffer *rxb;
+ struct iwl_rx_packet *pkt;
+ struct iwl_rx_queue *rxq = &priv->rxq;
+ u32 r, i;
+ int reclaim;
+ unsigned long flags;
+ 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(priv, "r = %d, i = %d\n", r, i);
+
+ /* 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) {
+ int len;
+
+ rxb = rxq->queue[i];
+
+ /* If an RXB doesn't have a Rx queue slot associated with it,
+ * then a bug has been introduced in the queue refilling
+ * routines -- catch it here */
+ if (WARN_ON(rxb == NULL)) {
+ i = (i + 1) & RX_QUEUE_MASK;
+ continue;
+ }
+
+ rxq->queue[i] = NULL;
+
+ dma_unmap_page(priv->bus.dev, rxb->page_dma,
+ PAGE_SIZE << priv->hw_params.rx_page_order,
+ DMA_FROM_DEVICE);
+ pkt = rxb_addr(rxb);
+
+ IWL_DEBUG_RX(priv, "r = %d, i = %d, %s, 0x%02x\n", r,
+ i, get_cmd_string(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(priv, 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) &&
+ (pkt->hdr.cmd != REPLY_RX_PHY_CMD) &&
+ (pkt->hdr.cmd != REPLY_RX) &&
+ (pkt->hdr.cmd != REPLY_RX_MPDU_CMD) &&
+ (pkt->hdr.cmd != REPLY_COMPRESSED_BA) &&
+ (pkt->hdr.cmd != STATISTICS_NOTIFICATION) &&
+ (pkt->hdr.cmd != REPLY_TX);
+
+ iwl_rx_dispatch(priv, rxb);
+
+ /*
+ * XXX: After here, we should always check rxb->page
+ * against NULL before touching it or its virtual
+ * memory (pkt). Because some rx_handler might have
+ * already taken or freed the pages.
+ */
+
+ if (reclaim) {
+ /* Invoke any callbacks, transfer the buffer to caller,
+ * and fire off the (possibly) blocking
+ * trans_send_cmd()
+ * as we reclaim the driver command queue */
+ if (rxb->page)
+ iwl_tx_cmd_complete(priv, rxb);
+ else
+ IWL_WARN(priv, "Claim null rxb?\n");
+ }
+
+ /* 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(priv->bus.dev, rxb->page,
+ 0, PAGE_SIZE << priv->hw_params.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);
+
+ 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(priv);
+ count = 0;
+ }
+ }
+ }
+
+ /* Backtrack one entry */
+ rxq->read = i;
+ if (fill_rx)
+ iwlagn_rx_replenish_now(priv);
+ else
+ iwlagn_rx_queue_restock(priv);
+}
+
+/* tasklet for iwlagn interrupt */
+void iwl_irq_tasklet(struct iwl_priv *priv)
+{
+ u32 inta = 0;
+ u32 handled = 0;
+ unsigned long flags;
+ u32 i;
+#ifdef CONFIG_IWLWIFI_DEBUG
+ u32 inta_mask;
+#endif
+
+ spin_lock_irqsave(&priv->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(priv, CSR_INT, priv->_agn.inta | ~priv->inta_mask);
+
+ inta = priv->_agn.inta;
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+ if (iwl_get_debug_level(priv) & IWL_DL_ISR) {
+ /* just for debug */
+ inta_mask = iwl_read32(priv, CSR_INT_MASK);
+ IWL_DEBUG_ISR(priv, "inta 0x%08x, enabled 0x%08x\n ",
+ inta, inta_mask);
+ }
+#endif
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ /* saved interrupt in inta variable now we can reset priv->_agn.inta */
+ priv->_agn.inta = 0;
+
+ /* Now service all interrupt bits discovered above. */
+ if (inta & CSR_INT_BIT_HW_ERR) {
+ IWL_ERR(priv, "Hardware error detected. Restarting.\n");
+
+ /* Tell the device to stop sending interrupts */
+ iwl_disable_interrupts(priv);
+
+ priv->isr_stats.hw++;
+ iwl_irq_handle_error(priv);
+
+ handled |= CSR_INT_BIT_HW_ERR;
+
+ return;
+ }
+
+#ifdef CONFIG_IWLWIFI_DEBUG
+ if (iwl_get_debug_level(priv) & (IWL_DL_ISR)) {
+ /* NIC fires this, but we don't use it, redundant with WAKEUP */
+ if (inta & CSR_INT_BIT_SCD) {
+ IWL_DEBUG_ISR(priv, "Scheduler finished to transmit "
+ "the frame/frames.\n");
+ priv->isr_stats.sch++;
+ }
+
+ /* Alive notification via Rx interrupt will do the real work */
+ if (inta & CSR_INT_BIT_ALIVE) {
+ IWL_DEBUG_ISR(priv, "Alive interrupt\n");
+ priv->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) {
+ int hw_rf_kill = 0;
+ if (!(iwl_read32(priv, CSR_GP_CNTRL) &
+ CSR_GP_CNTRL_REG_FLAG_HW_RF_KILL_SW))
+ hw_rf_kill = 1;
+
+ IWL_WARN(priv, "RF_KILL bit toggled to %s.\n",
+ hw_rf_kill ? "disable radio" : "enable radio");
+
+ priv->isr_stats.rfkill++;
+
+ /* driver only loads ucode once setting the interface up.
+ * the driver allows loading the ucode even if the radio
+ * is killed. Hence update the killswitch state here. The
+ * rfkill handler will care about restarting if needed.
+ */
+ if (!test_bit(STATUS_ALIVE, &priv->status)) {
+ if (hw_rf_kill)
+ set_bit(STATUS_RF_KILL_HW, &priv->status);
+ else
+ clear_bit(STATUS_RF_KILL_HW, &priv->status);
+ wiphy_rfkill_set_hw_state(priv->hw->wiphy, hw_rf_kill);
+ }
+
+ handled |= CSR_INT_BIT_RF_KILL;
+ }
+
+ /* Chip got too hot and stopped itself */
+ if (inta & CSR_INT_BIT_CT_KILL) {
+ IWL_ERR(priv, "Microcode CT kill error detected.\n");
+ priv->isr_stats.ctkill++;
+ handled |= CSR_INT_BIT_CT_KILL;
+ }
+
+ /* Error detected by uCode */
+ if (inta & CSR_INT_BIT_SW_ERR) {
+ IWL_ERR(priv, "Microcode SW error detected. "
+ " Restarting 0x%X.\n", inta);
+ priv->isr_stats.sw++;
+ iwl_irq_handle_error(priv);
+ handled |= CSR_INT_BIT_SW_ERR;
+ }
+
+ /* uCode wakes up after power-down sleep */
+ if (inta & CSR_INT_BIT_WAKEUP) {
+ IWL_DEBUG_ISR(priv, "Wakeup interrupt\n");
+ iwl_rx_queue_update_write_ptr(priv, &priv->rxq);
+ for (i = 0; i < priv->hw_params.max_txq_num; i++)
+ iwl_txq_update_write_ptr(priv, &priv->txq[i]);
+
+ priv->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(priv, "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(priv, CSR_FH_INT_STATUS,
+ CSR_FH_INT_RX_MASK);
+ }
+ if (inta & CSR_INT_BIT_RX_PERIODIC) {
+ handled |= CSR_INT_BIT_RX_PERIODIC;
+ iwl_write32(priv, 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(priv, CSR_INT_PERIODIC_REG,
+ CSR_INT_PERIODIC_DIS);
+ iwl_rx_handle(priv);
+
+ /*
+ * 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(priv, CSR_INT_PERIODIC_REG,
+ CSR_INT_PERIODIC_ENA);
+
+ priv->isr_stats.rx++;
+ }
+
+ /* This "Tx" DMA channel is used only for loading uCode */
+ if (inta & CSR_INT_BIT_FH_TX) {
+ iwl_write32(priv, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
+ IWL_DEBUG_ISR(priv, "uCode load interrupt\n");
+ priv->isr_stats.tx++;
+ handled |= CSR_INT_BIT_FH_TX;
+ /* Wake up uCode load routine, now that load is complete */
+ priv->ucode_write_complete = 1;
+ wake_up_interruptible(&priv->wait_command_queue);
+ }
+
+ if (inta & ~handled) {
+ IWL_ERR(priv, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
+ priv->isr_stats.unhandled++;
+ }
+
+ if (inta & ~(priv->inta_mask)) {
+ IWL_WARN(priv, "Disabled INTA bits 0x%08x were pending\n",
+ inta & ~priv->inta_mask);
+ }
+
+ /* Re-enable all interrupts */
+ /* only Re-enable if disabled by irq */
+ if (test_bit(STATUS_INT_ENABLED, &priv->status))
+ iwl_enable_interrupts(priv);
+ /* Re-enable RF_KILL if it occurred */
+ else if (handled & CSR_INT_BIT_RF_KILL)
+ iwl_enable_rfkill_int(priv);
+}
+