drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2011 Intel Corporation. All rights reserved.
   4  *
   5  * Portions of this file are derived from the ipw3945 project, as well
   6  * as portions of the ieee80211 subsystem header files.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  20  *
  21  * The full GNU General Public License is included in this distribution in the
  22  * file called LICENSE.
  23  *
  24  * Contact Information:
  25  *  Intel Linux Wireless <ilw@linux.intel.com>
  26  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  27  *
  28  *****************************************************************************/
  29 #include <linux/sched.h>
  30 #include <linux/wait.h>
  31 #include <linux/gfp.h>
  32
  33 /*TODO: Remove include to iwl-core.h*/
  34 #include "iwl-core.h"
  35 #include "iwl-io.h"
  36 #include "iwl-trans-pcie-int.h"
  37
  38 /******************************************************************************
  39  *
  40  * RX path functions
  41  *
  42  ******************************************************************************/
  43
  44 /*
  45  * Rx theory of operation
  46  *
  47  * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
  48  * each of which point to Receive Buffers to be filled by the NIC.  These get
  49  * used not only for Rx frames, but for any command response or notification
  50  * from the NIC.  The driver and NIC manage the Rx buffers by means
  51  * of indexes into the circular buffer.
  52  *
  53  * Rx Queue Indexes
  54  * The host/firmware share two index registers for managing the Rx buffers.
  55  *
  56  * The READ index maps to the first position that the firmware may be writing
  57  * to -- the driver can read up to (but not including) this position and get
  58  * good data.
  59  * The READ index is managed by the firmware once the card is enabled.
  60  *
  61  * The WRITE index maps to the last position the driver has read from -- the
  62  * position preceding WRITE is the last slot the firmware can place a packet.
  63  *
  64  * The queue is empty (no good data) if WRITE = READ - 1, and is full if
  65  * WRITE = READ.
  66  *
  67  * During initialization, the host sets up the READ queue position to the first
  68  * INDEX position, and WRITE to the last (READ - 1 wrapped)
  69  *
  70  * When the firmware places a packet in a buffer, it will advance the READ index
  71  * and fire the RX interrupt.  The driver can then query the READ index and
  72  * process as many packets as possible, moving the WRITE index forward as it
  73  * resets the Rx queue buffers with new memory.
  74  *
  75  * The management in the driver is as follows:
  76  * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free.  When
  77  *   iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
  78  *   to replenish the iwl->rxq->rx_free.
  79  * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the
  80  *   iwl->rxq is replenished and the READ INDEX is updated (updating the
  81  *   'processed' and 'read' driver indexes as well)
  82  * + A received packet is processed and handed to the kernel network stack,
  83  *   detached from the iwl->rxq.  The driver 'processed' index is updated.
  84  * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
  85  *   list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
  86  *   INDEX is not incremented and iwl->status(RX_STALLED) is set.  If there
  87  *   were enough free buffers and RX_STALLED is set it is cleared.
  88  *
  89  *
  90  * Driver sequence:
  91  *
  92  * iwl_rx_queue_alloc()   Allocates rx_free
  93  * iwl_rx_replenish()     Replenishes rx_free list from rx_used, and calls
  94  *                            iwl_rx_queue_restock
  95  * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx
  96  *                            queue, updates firmware pointers, and updates
  97  *                            the WRITE index.  If insufficient rx_free buffers
  98  *                            are available, schedules iwl_rx_replenish
  99  *
 100  * -- enable interrupts --
 101  * ISR - iwl_rx()         Detach iwl_rx_mem_buffers from pool up to the
 102  *                            READ INDEX, detaching the SKB from the pool.
 103  *                            Moves the packet buffer from queue to rx_used.
 104  *                            Calls iwl_rx_queue_restock to refill any empty
 105  *                            slots.
 106  * ...
 107  *
 108  */
 109
 110 /**
 111  * iwl_rx_queue_space - Return number of free slots available in queue.
 112  */
 113 static int iwl_rx_queue_space(const struct iwl_rx_queue *q)
 114 {
 115         int s = q->read - q->write;
 116         if (s <= 0)
 117                 s += RX_QUEUE_SIZE;
 118         /* keep some buffer to not confuse full and empty queue */
 119         s -= 2;
 120         if (s < 0)
 121                 s = 0;
 122         return s;
 123 }
 124
 125 /**
 126  * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
 127  */
 128 void iwl_rx_queue_update_write_ptr(struct iwl_trans *trans,
 129                         struct iwl_rx_queue *q)
 130 {
 131         unsigned long flags;
 132         u32 reg;
 133
 134         spin_lock_irqsave(&q->lock, flags);
 135
 136         if (q->need_update == 0)
 137                 goto exit_unlock;
 138
 139         if (hw_params(trans).shadow_reg_enable) {
 140                 /* shadow register enabled */
 141                 /* Device expects a multiple of 8 */
 142                 q->write_actual = (q->write & ~0x7);
 143                 iwl_write32(bus(trans), FH_RSCSR_CHNL0_WPTR, q->write_actual);
 144         } else {
 145                 /* If power-saving is in use, make sure device is awake */
 146                 if (test_bit(STATUS_POWER_PMI, &trans->shrd->status)) {
 147                         reg = iwl_read32(bus(trans), CSR_UCODE_DRV_GP1);
 148
 149                         if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
 150                                 IWL_DEBUG_INFO(trans,
 151                                         "Rx queue requesting wakeup,"
 152                                         " GP1 = 0x%x\n", reg);
 153                                 iwl_set_bit(bus(trans), CSR_GP_CNTRL,
 154                                         CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 155                                 goto exit_unlock;
 156                         }
 157
 158                         q->write_actual = (q->write & ~0x7);
 159                         iwl_write_direct32(bus(trans), FH_RSCSR_CHNL0_WPTR,
 160                                         q->write_actual);
 161
 162                 /* Else device is assumed to be awake */
 163                 } else {
 164                         /* Device expects a multiple of 8 */
 165                         q->write_actual = (q->write & ~0x7);
 166                         iwl_write_direct32(bus(trans), FH_RSCSR_CHNL0_WPTR,
 167                                 q->write_actual);
 168                 }
 169         }
 170         q->need_update = 0;
 171
 172  exit_unlock:
 173         spin_unlock_irqrestore(&q->lock, flags);
 174 }
 175
 176 /**
 177  * iwlagn_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
 178  */
 179 static inline __le32 iwlagn_dma_addr2rbd_ptr(dma_addr_t dma_addr)
 180 {
 181         return cpu_to_le32((u32)(dma_addr >> 8));
 182 }
 183
 184 /**
 185  * iwlagn_rx_queue_restock - refill RX queue from pre-allocated pool
 186  *
 187  * If there are slots in the RX queue that need to be restocked,
 188  * and we have free pre-allocated buffers, fill the ranks as much
 189  * as we can, pulling from rx_free.
 190  *
 191  * This moves the 'write' index forward to catch up with 'processed', and
 192  * also updates the memory address in the firmware to reference the new
 193  * target buffer.
 194  */
 195 static void iwlagn_rx_queue_restock(struct iwl_trans *trans)
 196 {
 197         struct iwl_trans_pcie *trans_pcie =
 198                 IWL_TRANS_GET_PCIE_TRANS(trans);
 199
 200         struct iwl_rx_queue *rxq = &trans_pcie->rxq;
 201         struct list_head *element;
 202         struct iwl_rx_mem_buffer *rxb;
 203         unsigned long flags;
 204
 205         spin_lock_irqsave(&rxq->lock, flags);
 206         while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
 207                 /* The overwritten rxb must be a used one */
 208                 rxb = rxq->queue[rxq->write];
 209                 BUG_ON(rxb && rxb->page);
 210
 211                 /* Get next free Rx buffer, remove from free list */
 212                 element = rxq->rx_free.next;
 213                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 214                 list_del(element);
 215
 216                 /* Point to Rx buffer via next RBD in circular buffer */
 217                 rxq->bd[rxq->write] = iwlagn_dma_addr2rbd_ptr(rxb->page_dma);
 218                 rxq->queue[rxq->write] = rxb;
 219                 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
 220                 rxq->free_count--;
 221         }
 222         spin_unlock_irqrestore(&rxq->lock, flags);
 223         /* If the pre-allocated buffer pool is dropping low, schedule to
 224          * refill it */
 225         if (rxq->free_count <= RX_LOW_WATERMARK)
 226                 queue_work(trans->shrd->workqueue, &trans_pcie->rx_replenish);
 227
 228
 229         /* If we've added more space for the firmware to place data, tell it.
 230          * Increment device's write pointer in multiples of 8. */
 231         if (rxq->write_actual != (rxq->write & ~0x7)) {
 232                 spin_lock_irqsave(&rxq->lock, flags);
 233                 rxq->need_update = 1;
 234                 spin_unlock_irqrestore(&rxq->lock, flags);
 235                 iwl_rx_queue_update_write_ptr(trans, rxq);
 236         }
 237 }
 238
 239 /**
 240  * iwlagn_rx_replenish - Move all used packet from rx_used to rx_free
 241  *
 242  * When moving to rx_free an SKB is allocated for the slot.
 243  *
 244  * Also restock the Rx queue via iwl_rx_queue_restock.
 245  * This is called as a scheduled work item (except for during initialization)
 246  */
 247 static void iwlagn_rx_allocate(struct iwl_trans *trans, gfp_t priority)
 248 {
 249         struct iwl_trans_pcie *trans_pcie =
 250                 IWL_TRANS_GET_PCIE_TRANS(trans);
 251
 252         struct iwl_rx_queue *rxq = &trans_pcie->rxq;
 253         struct list_head *element;
 254         struct iwl_rx_mem_buffer *rxb;
 255         struct page *page;
 256         unsigned long flags;
 257         gfp_t gfp_mask = priority;
 258
 259         while (1) {
 260                 spin_lock_irqsave(&rxq->lock, flags);
 261                 if (list_empty(&rxq->rx_used)) {
 262                         spin_unlock_irqrestore(&rxq->lock, flags);
 263                         return;
 264                 }
 265                 spin_unlock_irqrestore(&rxq->lock, flags);
 266
 267                 if (rxq->free_count > RX_LOW_WATERMARK)
 268                         gfp_mask |= __GFP_NOWARN;
 269
 270                 if (hw_params(trans).rx_page_order > 0)
 271                         gfp_mask |= __GFP_COMP;
 272
 273                 /* Alloc a new receive buffer */
 274                 page = alloc_pages(gfp_mask,
 275                                   hw_params(trans).rx_page_order);
 276                 if (!page) {
 277                         if (net_ratelimit())
 278                                 IWL_DEBUG_INFO(trans, "alloc_pages failed, "
 279                                            "order: %d\n",
 280                                            hw_params(trans).rx_page_order);
 281
 282                         if ((rxq->free_count <= RX_LOW_WATERMARK) &&
 283                             net_ratelimit())
 284                                 IWL_CRIT(trans, "Failed to alloc_pages with %s."
 285                                          "Only %u free buffers remaining.\n",
 286                                          priority == GFP_ATOMIC ?
 287                                          "GFP_ATOMIC" : "GFP_KERNEL",
 288                                          rxq->free_count);
 289                         /* We don't reschedule replenish work here -- we will
 290                          * call the restock method and if it still needs
 291                          * more buffers it will schedule replenish */
 292                         return;
 293                 }
 294
 295                 spin_lock_irqsave(&rxq->lock, flags);
 296
 297                 if (list_empty(&rxq->rx_used)) {
 298                         spin_unlock_irqrestore(&rxq->lock, flags);
 299                         __free_pages(page, hw_params(trans).rx_page_order);
 300                         return;
 301                 }
 302                 element = rxq->rx_used.next;
 303                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 304                 list_del(element);
 305
 306                 spin_unlock_irqrestore(&rxq->lock, flags);
 307
 308                 BUG_ON(rxb->page);
 309                 rxb->page = page;
 310                 /* Get physical address of the RB */
 311                 rxb->page_dma = dma_map_page(bus(trans)->dev, page, 0,
 312                                 PAGE_SIZE << hw_params(trans).rx_page_order,
 313                                 DMA_FROM_DEVICE);
 314                 /* dma address must be no more than 36 bits */
 315                 BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
 316                 /* and also 256 byte aligned! */
 317                 BUG_ON(rxb->page_dma & DMA_BIT_MASK(8));
 318
 319                 spin_lock_irqsave(&rxq->lock, flags);
 320
 321                 list_add_tail(&rxb->list, &rxq->rx_free);
 322                 rxq->free_count++;
 323
 324                 spin_unlock_irqrestore(&rxq->lock, flags);
 325         }
 326 }
 327
 328 void iwlagn_rx_replenish(struct iwl_trans *trans)
 329 {
 330         unsigned long flags;
 331
 332         iwlagn_rx_allocate(trans, GFP_KERNEL);
 333
 334         spin_lock_irqsave(&trans->shrd->lock, flags);
 335         iwlagn_rx_queue_restock(trans);
 336         spin_unlock_irqrestore(&trans->shrd->lock, flags);
 337 }
 338
 339 static void iwlagn_rx_replenish_now(struct iwl_trans *trans)
 340 {
 341         iwlagn_rx_allocate(trans, GFP_ATOMIC);
 342
 343         iwlagn_rx_queue_restock(trans);
 344 }
 345
 346 void iwl_bg_rx_replenish(struct work_struct *data)
 347 {
 348         struct iwl_trans_pcie *trans_pcie =
 349             container_of(data, struct iwl_trans_pcie, rx_replenish);
 350         struct iwl_trans *trans = trans_pcie->trans;
 351
 352         if (test_bit(STATUS_EXIT_PENDING, &trans->shrd->status))
 353                 return;
 354
 355         mutex_lock(&trans->shrd->mutex);
 356         iwlagn_rx_replenish(trans);
 357         mutex_unlock(&trans->shrd->mutex);
 358 }
 359
 360 /**
 361  * iwl_rx_handle - Main entry function for receiving responses from uCode
 362  *
 363  * Uses the priv->rx_handlers callback function array to invoke
 364  * the appropriate handlers, including command responses,
 365  * frame-received notifications, and other notifications.
 366  */
 367 static void iwl_rx_handle(struct iwl_trans *trans)
 368 {
 369         struct iwl_rx_mem_buffer *rxb;
 370         struct iwl_rx_packet *pkt;
 371         struct iwl_trans_pcie *trans_pcie =
 372                 IWL_TRANS_GET_PCIE_TRANS(trans);
 373         struct iwl_rx_queue *rxq = &trans_pcie->rxq;
 374         struct iwl_tx_queue *txq = &trans_pcie->txq[trans->shrd->cmd_queue];
 375         struct iwl_device_cmd *cmd;
 376         u32 r, i;
 377         int reclaim;
 378         unsigned long flags;
 379         u8 fill_rx = 0;
 380         u32 count = 8;
 381         int total_empty;
 382         int index, cmd_index;
 383
 384         /* uCode's read index (stored in shared DRAM) indicates the last Rx
 385          * buffer that the driver may process (last buffer filled by ucode). */
 386         r = le16_to_cpu(rxq->rb_stts->closed_rb_num) &  0x0FFF;
 387         i = rxq->read;
 388
 389         /* Rx interrupt, but nothing sent from uCode */
 390         if (i == r)
 391                 IWL_DEBUG_RX(trans, "r = %d, i = %d\n", r, i);
 392
 393         /* calculate total frames need to be restock after handling RX */
 394         total_empty = r - rxq->write_actual;
 395         if (total_empty < 0)
 396                 total_empty += RX_QUEUE_SIZE;
 397
 398         if (total_empty > (RX_QUEUE_SIZE / 2))
 399                 fill_rx = 1;
 400
 401         while (i != r) {
 402                 int len, err;
 403                 u16 sequence;
 404
 405                 rxb = rxq->queue[i];
 406
 407                 /* If an RXB doesn't have a Rx queue slot associated with it,
 408                  * then a bug has been introduced in the queue refilling
 409                  * routines -- catch it here */
 410                 if (WARN_ON(rxb == NULL)) {
 411                         i = (i + 1) & RX_QUEUE_MASK;
 412                         continue;
 413                 }
 414
 415                 rxq->queue[i] = NULL;
 416
 417                 dma_unmap_page(bus(trans)->dev, rxb->page_dma,
 418                                PAGE_SIZE << hw_params(trans).rx_page_order,
 419                                DMA_FROM_DEVICE);
 420                 pkt = rxb_addr(rxb);
 421
 422                 IWL_DEBUG_RX(trans, "r = %d, i = %d, %s, 0x%02x\n", r,
 423                         i, get_cmd_string(pkt->hdr.cmd), pkt->hdr.cmd);
 424
 425                 len = le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK;
 426                 len += sizeof(u32); /* account for status word */
 427                 trace_iwlwifi_dev_rx(priv(trans), pkt, len);
 428
 429                 /* Reclaim a command buffer only if this packet is a response
 430                  *   to a (driver-originated) command.
 431                  * If the packet (e.g. Rx frame) originated from uCode,
 432                  *   there is no command buffer to reclaim.
 433                  * Ucode should set SEQ_RX_FRAME bit if ucode-originated,
 434                  *   but apparently a few don't get set; catch them here. */
 435                 reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME) &&
 436                         (pkt->hdr.cmd != REPLY_RX_PHY_CMD) &&
 437                         (pkt->hdr.cmd != REPLY_RX) &&
 438                         (pkt->hdr.cmd != REPLY_RX_MPDU_CMD) &&
 439                         (pkt->hdr.cmd != REPLY_COMPRESSED_BA) &&
 440                         (pkt->hdr.cmd != STATISTICS_NOTIFICATION) &&
 441                         (pkt->hdr.cmd != REPLY_TX);
 442
 443                 sequence = le16_to_cpu(pkt->hdr.sequence);
 444                 index = SEQ_TO_INDEX(sequence);
 445                 cmd_index = get_cmd_index(&txq->q, index);
 446
 447                 if (reclaim)
 448                         cmd = txq->cmd[cmd_index];
 449                 else
 450                         cmd = NULL;
 451
 452                 /* warn if this is cmd response / notification and the uCode
 453                  * didn't set the SEQ_RX_FRAME for a frame that is
 454                  * uCode-originated
 455                  * If you saw this code after the second half of 2012, then
 456                  * please remove it
 457                  */
 458                 WARN(pkt->hdr.cmd != REPLY_TX && reclaim == false &&
 459                      (!(pkt->hdr.sequence & SEQ_RX_FRAME)),
 460                      "reclaim is false, SEQ_RX_FRAME unset: %s\n",
 461                      get_cmd_string(pkt->hdr.cmd));
 462
 463                 err = iwl_rx_dispatch(priv(trans), rxb, cmd);
 464
 465                 /*
 466                  * XXX: After here, we should always check rxb->page
 467                  * against NULL before touching it or its virtual
 468                  * memory (pkt). Because some rx_handler might have
 469                  * already taken or freed the pages.
 470                  */
 471
 472                 if (reclaim) {
 473                         /* Invoke any callbacks, transfer the buffer to caller,
 474                          * and fire off the (possibly) blocking
 475                          * iwl_trans_send_cmd()
 476                          * as we reclaim the driver command queue */
 477                         if (rxb->page)
 478                                 iwl_tx_cmd_complete(trans, rxb, err);
 479                         else
 480                                 IWL_WARN(trans, "Claim null rxb?\n");
 481                 }
 482
 483                 /* Reuse the page if possible. For notification packets and
 484                  * SKBs that fail to Rx correctly, add them back into the
 485                  * rx_free list for reuse later. */
 486                 spin_lock_irqsave(&rxq->lock, flags);
 487                 if (rxb->page != NULL) {
 488                         rxb->page_dma = dma_map_page(bus(trans)->dev, rxb->page,
 489                                 0, PAGE_SIZE <<
 490                                     hw_params(trans).rx_page_order,
 491                                 DMA_FROM_DEVICE);
 492                         list_add_tail(&rxb->list, &rxq->rx_free);
 493                         rxq->free_count++;
 494                 } else
 495                         list_add_tail(&rxb->list, &rxq->rx_used);
 496
 497                 spin_unlock_irqrestore(&rxq->lock, flags);
 498
 499                 i = (i + 1) & RX_QUEUE_MASK;
 500                 /* If there are a lot of unused frames,
 501                  * restock the Rx queue so ucode wont assert. */
 502                 if (fill_rx) {
 503                         count++;
 504                         if (count >= 8) {
 505                                 rxq->read = i;
 506                                 iwlagn_rx_replenish_now(trans);
 507                                 count = 0;
 508                         }
 509                 }
 510         }
 511
 512         /* Backtrack one entry */
 513         rxq->read = i;
 514         if (fill_rx)
 515                 iwlagn_rx_replenish_now(trans);
 516         else
 517                 iwlagn_rx_queue_restock(trans);
 518 }
 519
 520 static const char * const desc_lookup_text[] = {
 521         "OK",
 522         "FAIL",
 523         "BAD_PARAM",
 524         "BAD_CHECKSUM",
 525         "NMI_INTERRUPT_WDG",
 526         "SYSASSERT",
 527         "FATAL_ERROR",
 528         "BAD_COMMAND",
 529         "HW_ERROR_TUNE_LOCK",
 530         "HW_ERROR_TEMPERATURE",
 531         "ILLEGAL_CHAN_FREQ",
 532         "VCC_NOT_STABLE",
 533         "FH_ERROR",
 534         "NMI_INTERRUPT_HOST",
 535         "NMI_INTERRUPT_ACTION_PT",
 536         "NMI_INTERRUPT_UNKNOWN",
 537         "UCODE_VERSION_MISMATCH",
 538         "HW_ERROR_ABS_LOCK",
 539         "HW_ERROR_CAL_LOCK_FAIL",
 540         "NMI_INTERRUPT_INST_ACTION_PT",
 541         "NMI_INTERRUPT_DATA_ACTION_PT",
 542         "NMI_TRM_HW_ER",
 543         "NMI_INTERRUPT_TRM",
 544         "NMI_INTERRUPT_BREAK_POINT",
 545         "DEBUG_0",
 546         "DEBUG_1",
 547         "DEBUG_2",
 548         "DEBUG_3",
 549 };
 550
 551 static struct { char *name; u8 num; } advanced_lookup[] = {
 552         { "NMI_INTERRUPT_WDG", 0x34 },
 553         { "SYSASSERT", 0x35 },
 554         { "UCODE_VERSION_MISMATCH", 0x37 },
 555         { "BAD_COMMAND", 0x38 },
 556         { "NMI_INTERRUPT_DATA_ACTION_PT", 0x3C },
 557         { "FATAL_ERROR", 0x3D },
 558         { "NMI_TRM_HW_ERR", 0x46 },
 559         { "NMI_INTERRUPT_TRM", 0x4C },
 560         { "NMI_INTERRUPT_BREAK_POINT", 0x54 },
 561         { "NMI_INTERRUPT_WDG_RXF_FULL", 0x5C },
 562         { "NMI_INTERRUPT_WDG_NO_RBD_RXF_FULL", 0x64 },
 563         { "NMI_INTERRUPT_HOST", 0x66 },
 564         { "NMI_INTERRUPT_ACTION_PT", 0x7C },
 565         { "NMI_INTERRUPT_UNKNOWN", 0x84 },
 566         { "NMI_INTERRUPT_INST_ACTION_PT", 0x86 },
 567         { "ADVANCED_SYSASSERT", 0 },
 568 };
 569
 570 static const char *desc_lookup(u32 num)
 571 {
 572         int i;
 573         int max = ARRAY_SIZE(desc_lookup_text);
 574
 575         if (num < max)
 576                 return desc_lookup_text[num];
 577
 578         max = ARRAY_SIZE(advanced_lookup) - 1;
 579         for (i = 0; i < max; i++) {
 580                 if (advanced_lookup[i].num == num)
 581                         break;
 582         }
 583         return advanced_lookup[i].name;
 584 }
 585
 586 #define ERROR_START_OFFSET  (1 * sizeof(u32))
 587 #define ERROR_ELEM_SIZE     (7 * sizeof(u32))
 588
 589 static void iwl_dump_nic_error_log(struct iwl_trans *trans)
 590 {
 591         u32 base;
 592         struct iwl_error_event_table table;
 593         struct iwl_priv *priv = priv(trans);
 594         struct iwl_trans_pcie *trans_pcie =
 595                 IWL_TRANS_GET_PCIE_TRANS(trans);
 596
 597         base = priv->device_pointers.error_event_table;
 598         if (priv->ucode_type == IWL_UCODE_INIT) {
 599                 if (!base)
 600                         base = priv->init_errlog_ptr;
 601         } else {
 602                 if (!base)
 603                         base = priv->inst_errlog_ptr;
 604         }
 605
 606         if (!iwlagn_hw_valid_rtc_data_addr(base)) {
 607                 IWL_ERR(trans,
 608                         "Not valid error log pointer 0x%08X for %s uCode\n",
 609                         base,
 610                         (priv->ucode_type == IWL_UCODE_INIT)
 611                                         ? "Init" : "RT");
 612                 return;
 613         }
 614
 615         iwl_read_targ_mem_words(bus(priv), base, &table, sizeof(table));
 616
 617         if (ERROR_START_OFFSET <= table.valid * ERROR_ELEM_SIZE) {
 618                 IWL_ERR(trans, "Start IWL Error Log Dump:\n");
 619                 IWL_ERR(trans, "Status: 0x%08lX, count: %d\n",
 620                         trans->shrd->status, table.valid);
 621         }
 622
 623         trans_pcie->isr_stats.err_code = table.error_id;
 624
 625         trace_iwlwifi_dev_ucode_error(priv, table.error_id, table.tsf_low,
 626                                       table.data1, table.data2, table.line,
 627                                       table.blink1, table.blink2, table.ilink1,
 628                                       table.ilink2, table.bcon_time, table.gp1,
 629                                       table.gp2, table.gp3, table.ucode_ver,
 630                                       table.hw_ver, table.brd_ver);
 631         IWL_ERR(trans, "0x%08X | %-28s\n", table.error_id,
 632                 desc_lookup(table.error_id));
 633         IWL_ERR(trans, "0x%08X | uPc\n", table.pc);
 634         IWL_ERR(trans, "0x%08X | branchlink1\n", table.blink1);
 635         IWL_ERR(trans, "0x%08X | branchlink2\n", table.blink2);
 636         IWL_ERR(trans, "0x%08X | interruptlink1\n", table.ilink1);
 637         IWL_ERR(trans, "0x%08X | interruptlink2\n", table.ilink2);
 638         IWL_ERR(trans, "0x%08X | data1\n", table.data1);
 639         IWL_ERR(trans, "0x%08X | data2\n", table.data2);
 640         IWL_ERR(trans, "0x%08X | line\n", table.line);
 641         IWL_ERR(trans, "0x%08X | beacon time\n", table.bcon_time);
 642         IWL_ERR(trans, "0x%08X | tsf low\n", table.tsf_low);
 643         IWL_ERR(trans, "0x%08X | tsf hi\n", table.tsf_hi);
 644         IWL_ERR(trans, "0x%08X | time gp1\n", table.gp1);
 645         IWL_ERR(trans, "0x%08X | time gp2\n", table.gp2);
 646         IWL_ERR(trans, "0x%08X | time gp3\n", table.gp3);
 647         IWL_ERR(trans, "0x%08X | uCode version\n", table.ucode_ver);
 648         IWL_ERR(trans, "0x%08X | hw version\n", table.hw_ver);
 649         IWL_ERR(trans, "0x%08X | board version\n", table.brd_ver);
 650         IWL_ERR(trans, "0x%08X | hcmd\n", table.hcmd);
 651 }
 652
 653 /**
 654  * iwl_irq_handle_error - called for HW or SW error interrupt from card
 655  */
 656 static void iwl_irq_handle_error(struct iwl_trans *trans)
 657 {
 658         struct iwl_priv *priv = priv(trans);
 659         /* W/A for WiFi/WiMAX coex and WiMAX own the RF */
 660         if (priv->cfg->internal_wimax_coex &&
 661             (!(iwl_read_prph(bus(trans), APMG_CLK_CTRL_REG) &
 662                         APMS_CLK_VAL_MRB_FUNC_MODE) ||
 663              (iwl_read_prph(bus(trans), APMG_PS_CTRL_REG) &
 664                         APMG_PS_CTRL_VAL_RESET_REQ))) {
 665                 /*
 666                  * Keep the restart process from trying to send host
 667                  * commands by clearing the ready bit.
 668                  */
 669                 clear_bit(STATUS_READY, &trans->shrd->status);
 670                 clear_bit(STATUS_HCMD_ACTIVE, &trans->shrd->status);
 671                 wake_up(&priv->shrd->wait_command_queue);
 672                 IWL_ERR(trans, "RF is used by WiMAX\n");
 673                 return;
 674         }
 675
 676         IWL_ERR(trans, "Loaded firmware version: %s\n",
 677                 priv->hw->wiphy->fw_version);
 678
 679         iwl_dump_nic_error_log(trans);
 680         iwl_dump_csr(trans);
 681         iwl_dump_fh(trans, NULL, false);
 682         iwl_dump_nic_event_log(trans, false, NULL, false);
 683 #ifdef CONFIG_IWLWIFI_DEBUG
 684         if (iwl_get_debug_level(trans->shrd) & IWL_DL_FW_ERRORS)
 685                 iwl_print_rx_config_cmd(priv(trans), IWL_RXON_CTX_BSS);
 686 #endif
 687
 688         iwlagn_fw_error(priv, false);
 689 }
 690
 691 #define EVENT_START_OFFSET  (4 * sizeof(u32))
 692
 693 /**
 694  * iwl_print_event_log - Dump error event log to syslog
 695  *
 696  */
 697 static int iwl_print_event_log(struct iwl_trans *trans, u32 start_idx,
 698                                u32 num_events, u32 mode,
 699                                int pos, char **buf, size_t bufsz)
 700 {
 701         u32 i;
 702         u32 base;       /* SRAM byte address of event log header */
 703         u32 event_size; /* 2 u32s, or 3 u32s if timestamp recorded */
 704         u32 ptr;        /* SRAM byte address of log data */
 705         u32 ev, time, data; /* event log data */
 706         unsigned long reg_flags;
 707         struct iwl_priv *priv = priv(trans);
 708
 709         if (num_events == 0)
 710                 return pos;
 711
 712         base = priv->device_pointers.log_event_table;
 713         if (priv->ucode_type == IWL_UCODE_INIT) {
 714                 if (!base)
 715                         base = priv->init_evtlog_ptr;
 716         } else {
 717                 if (!base)
 718                         base = priv->inst_evtlog_ptr;
 719         }
 720
 721         if (mode == 0)
 722                 event_size = 2 * sizeof(u32);
 723         else
 724                 event_size = 3 * sizeof(u32);
 725
 726         ptr = base + EVENT_START_OFFSET + (start_idx * event_size);
 727
 728         /* Make sure device is powered up for SRAM reads */
 729         spin_lock_irqsave(&bus(trans)->reg_lock, reg_flags);
 730         iwl_grab_nic_access(bus(trans));
 731
 732         /* Set starting address; reads will auto-increment */
 733         iwl_write32(bus(trans), HBUS_TARG_MEM_RADDR, ptr);
 734         rmb();
 735
 736         /* "time" is actually "data" for mode 0 (no timestamp).
 737         * place event id # at far right for easier visual parsing. */
 738         for (i = 0; i < num_events; i++) {
 739                 ev = iwl_read32(bus(trans), HBUS_TARG_MEM_RDAT);
 740                 time = iwl_read32(bus(trans), HBUS_TARG_MEM_RDAT);
 741                 if (mode == 0) {
 742                         /* data, ev */
 743                         if (bufsz) {
 744                                 pos += scnprintf(*buf + pos, bufsz - pos,
 745                                                 "EVT_LOG:0x%08x:%04u\n",
 746                                                 time, ev);
 747                         } else {
 748                                 trace_iwlwifi_dev_ucode_event(priv, 0,
 749                                         time, ev);
 750                                 IWL_ERR(trans, "EVT_LOG:0x%08x:%04u\n",
 751                                         time, ev);
 752                         }
 753                 } else {
 754                         data = iwl_read32(bus(trans), HBUS_TARG_MEM_RDAT);
 755                         if (bufsz) {
 756                                 pos += scnprintf(*buf + pos, bufsz - pos,
 757                                                 "EVT_LOGT:%010u:0x%08x:%04u\n",
 758                                                  time, data, ev);
 759                         } else {
 760                                 IWL_ERR(trans, "EVT_LOGT:%010u:0x%08x:%04u\n",
 761                                         time, data, ev);
 762                                 trace_iwlwifi_dev_ucode_event(priv, time,
 763                                         data, ev);
 764                         }
 765                 }
 766         }
 767
 768         /* Allow device to power down */
 769         iwl_release_nic_access(bus(trans));
 770         spin_unlock_irqrestore(&bus(trans)->reg_lock, reg_flags);
 771         return pos;
 772 }
 773
 774 /**
 775  * iwl_print_last_event_logs - Dump the newest # of event log to syslog
 776  */
 777 static int iwl_print_last_event_logs(struct iwl_trans *trans, u32 capacity,
 778                                     u32 num_wraps, u32 next_entry,
 779                                     u32 size, u32 mode,
 780                                     int pos, char **buf, size_t bufsz)
 781 {
 782         /*
 783          * display the newest DEFAULT_LOG_ENTRIES entries
 784          * i.e the entries just before the next ont that uCode would fill.
 785          */
 786         if (num_wraps) {
 787                 if (next_entry < size) {
 788                         pos = iwl_print_event_log(trans,
 789                                                 capacity - (size - next_entry),
 790                                                 size - next_entry, mode,
 791                                                 pos, buf, bufsz);
 792                         pos = iwl_print_event_log(trans, 0,
 793                                                   next_entry, mode,
 794                                                   pos, buf, bufsz);
 795                 } else
 796                         pos = iwl_print_event_log(trans, next_entry - size,
 797                                                   size, mode, pos, buf, bufsz);
 798         } else {
 799                 if (next_entry < size) {
 800                         pos = iwl_print_event_log(trans, 0, next_entry,
 801                                                   mode, pos, buf, bufsz);
 802                 } else {
 803                         pos = iwl_print_event_log(trans, next_entry - size,
 804                                                   size, mode, pos, buf, bufsz);
 805                 }
 806         }
 807         return pos;
 808 }
 809
 810 #define DEFAULT_DUMP_EVENT_LOG_ENTRIES (20)
 811
 812 int iwl_dump_nic_event_log(struct iwl_trans *trans, bool full_log,
 813                             char **buf, bool display)
 814 {
 815         u32 base;       /* SRAM byte address of event log header */
 816         u32 capacity;   /* event log capacity in # entries */
 817         u32 mode;       /* 0 - no timestamp, 1 - timestamp recorded */
 818         u32 num_wraps;  /* # times uCode wrapped to top of log */
 819         u32 next_entry; /* index of next entry to be written by uCode */
 820         u32 size;       /* # entries that we'll print */
 821         u32 logsize;
 822         int pos = 0;
 823         size_t bufsz = 0;
 824         struct iwl_priv *priv = priv(trans);
 825
 826         base = priv->device_pointers.log_event_table;
 827         if (priv->ucode_type == IWL_UCODE_INIT) {
 828                 logsize = priv->init_evtlog_size;
 829                 if (!base)
 830                         base = priv->init_evtlog_ptr;
 831         } else {
 832                 logsize = priv->inst_evtlog_size;
 833                 if (!base)
 834                         base = priv->inst_evtlog_ptr;
 835         }
 836
 837         if (!iwlagn_hw_valid_rtc_data_addr(base)) {
 838                 IWL_ERR(trans,
 839                         "Invalid event log pointer 0x%08X for %s uCode\n",
 840                         base,
 841                         (priv->ucode_type == IWL_UCODE_INIT)
 842                                         ? "Init" : "RT");
 843                 return -EINVAL;
 844         }
 845
 846         /* event log header */
 847         capacity = iwl_read_targ_mem(bus(trans), base);
 848         mode = iwl_read_targ_mem(bus(trans), base + (1 * sizeof(u32)));
 849         num_wraps = iwl_read_targ_mem(bus(trans), base + (2 * sizeof(u32)));
 850         next_entry = iwl_read_targ_mem(bus(trans), base + (3 * sizeof(u32)));
 851
 852         if (capacity > logsize) {
 853                 IWL_ERR(trans, "Log capacity %d is bogus, limit to %d "
 854                         "entries\n", capacity, logsize);
 855                 capacity = logsize;
 856         }
 857
 858         if (next_entry > logsize) {
 859                 IWL_ERR(trans, "Log write index %d is bogus, limit to %d\n",
 860                         next_entry, logsize);
 861                 next_entry = logsize;
 862         }
 863
 864         size = num_wraps ? capacity : next_entry;
 865
 866         /* bail out if nothing in log */
 867         if (size == 0) {
 868                 IWL_ERR(trans, "Start IWL Event Log Dump: nothing in log\n");
 869                 return pos;
 870         }
 871
 872 #ifdef CONFIG_IWLWIFI_DEBUG
 873         if (!(iwl_get_debug_level(trans->shrd) & IWL_DL_FW_ERRORS) && !full_log)
 874                 size = (size > DEFAULT_DUMP_EVENT_LOG_ENTRIES)
 875                         ? DEFAULT_DUMP_EVENT_LOG_ENTRIES : size;
 876 #else
 877         size = (size > DEFAULT_DUMP_EVENT_LOG_ENTRIES)
 878                 ? DEFAULT_DUMP_EVENT_LOG_ENTRIES : size;
 879 #endif
 880         IWL_ERR(trans, "Start IWL Event Log Dump: display last %u entries\n",
 881                 size);
 882
 883 #ifdef CONFIG_IWLWIFI_DEBUG
 884         if (display) {
 885                 if (full_log)
 886                         bufsz = capacity * 48;
 887                 else
 888                         bufsz = size * 48;
 889                 *buf = kmalloc(bufsz, GFP_KERNEL);
 890                 if (!*buf)
 891                         return -ENOMEM;
 892         }
 893         if ((iwl_get_debug_level(trans->shrd) & IWL_DL_FW_ERRORS) || full_log) {
 894                 /*
 895                  * if uCode has wrapped back to top of log,
 896                  * start at the oldest entry,
 897                  * i.e the next one that uCode would fill.
 898                  */
 899                 if (num_wraps)
 900                         pos = iwl_print_event_log(trans, next_entry,
 901                                                 capacity - next_entry, mode,
 902                                                 pos, buf, bufsz);
 903                 /* (then/else) start at top of log */
 904                 pos = iwl_print_event_log(trans, 0,
 905                                           next_entry, mode, pos, buf, bufsz);
 906         } else
 907                 pos = iwl_print_last_event_logs(trans, capacity, num_wraps,
 908                                                 next_entry, size, mode,
 909                                                 pos, buf, bufsz);
 910 #else
 911         pos = iwl_print_last_event_logs(trans, capacity, num_wraps,
 912                                         next_entry, size, mode,
 913                                         pos, buf, bufsz);
 914 #endif
 915         return pos;
 916 }
 917
 918 /* tasklet for iwlagn interrupt */
 919 void iwl_irq_tasklet(struct iwl_trans *trans)
 920 {
 921         u32 inta = 0;
 922         u32 handled = 0;
 923         unsigned long flags;
 924         u32 i;
 925 #ifdef CONFIG_IWLWIFI_DEBUG
 926         u32 inta_mask;
 927 #endif
 928
 929         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 930         struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
 931
 932
 933         spin_lock_irqsave(&trans->shrd->lock, flags);
 934
 935         /* Ack/clear/reset pending uCode interrupts.
 936          * Note:  Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS,
 937          */
 938         /* There is a hardware bug in the interrupt mask function that some
 939          * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if
 940          * they are disabled in the CSR_INT_MASK register. Furthermore the
 941          * ICT interrupt handling mechanism has another bug that might cause
 942          * these unmasked interrupts fail to be detected. We workaround the
 943          * hardware bugs here by ACKing all the possible interrupts so that
 944          * interrupt coalescing can still be achieved.
 945          */
 946         iwl_write32(bus(trans), CSR_INT,
 947                 trans_pcie->inta | ~trans_pcie->inta_mask);
 948
 949         inta = trans_pcie->inta;
 950
 951 #ifdef CONFIG_IWLWIFI_DEBUG
 952         if (iwl_get_debug_level(trans->shrd) & IWL_DL_ISR) {
 953                 /* just for debug */
 954                 inta_mask = iwl_read32(bus(trans), CSR_INT_MASK);
 955                 IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n ",
 956                                 inta, inta_mask);
 957         }
 958 #endif
 959
 960         spin_unlock_irqrestore(&trans->shrd->lock, flags);
 961
 962         /* saved interrupt in inta variable now we can reset trans_pcie->inta */
 963         trans_pcie->inta = 0;
 964
 965         /* Now service all interrupt bits discovered above. */
 966         if (inta & CSR_INT_BIT_HW_ERR) {
 967                 IWL_ERR(trans, "Hardware error detected.  Restarting.\n");
 968
 969                 /* Tell the device to stop sending interrupts */
 970                 iwl_disable_interrupts(trans);
 971
 972                 isr_stats->hw++;
 973                 iwl_irq_handle_error(trans);
 974
 975                 handled |= CSR_INT_BIT_HW_ERR;
 976
 977                 return;
 978         }
 979
 980 #ifdef CONFIG_IWLWIFI_DEBUG
 981         if (iwl_get_debug_level(trans->shrd) & (IWL_DL_ISR)) {
 982                 /* NIC fires this, but we don't use it, redundant with WAKEUP */
 983                 if (inta & CSR_INT_BIT_SCD) {
 984                         IWL_DEBUG_ISR(trans, "Scheduler finished to transmit "
 985                                       "the frame/frames.\n");
 986                         isr_stats->sch++;
 987                 }
 988
 989                 /* Alive notification via Rx interrupt will do the real work */
 990                 if (inta & CSR_INT_BIT_ALIVE) {
 991                         IWL_DEBUG_ISR(trans, "Alive interrupt\n");
 992                         isr_stats->alive++;
 993                 }
 994         }
 995 #endif
 996         /* Safely ignore these bits for debug checks below */
 997         inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE);
 998
 999         /* HW RF KILL switch toggled */
1000         if (inta & CSR_INT_BIT_RF_KILL) {
1001                 int hw_rf_kill = 0;
1002                 if (!(iwl_read32(bus(trans), CSR_GP_CNTRL) &
1003                                 CSR_GP_CNTRL_REG_FLAG_HW_RF_KILL_SW))
1004                         hw_rf_kill = 1;
1005
1006                 IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
1007                                 hw_rf_kill ? "disable radio" : "enable radio");
1008
1009                 isr_stats->rfkill++;
1010
1011                 /* driver only loads ucode once setting the interface up.
1012                  * the driver allows loading the ucode even if the radio
1013                  * is killed. Hence update the killswitch state here. The
1014                  * rfkill handler will care about restarting if needed.
1015                  */
1016                 if (!test_bit(STATUS_ALIVE, &trans->shrd->status)) {
1017                         if (hw_rf_kill)
1018                                 set_bit(STATUS_RF_KILL_HW,
1019                                         &trans->shrd->status);
1020                         else
1021                                 clear_bit(STATUS_RF_KILL_HW,
1022                                           &trans->shrd->status);
1023                         iwl_set_hw_rfkill_state(priv(trans), hw_rf_kill);
1024                 }
1025
1026                 handled |= CSR_INT_BIT_RF_KILL;
1027         }
1028
1029         /* Chip got too hot and stopped itself */
1030         if (inta & CSR_INT_BIT_CT_KILL) {
1031                 IWL_ERR(trans, "Microcode CT kill error detected.\n");
1032                 isr_stats->ctkill++;
1033                 handled |= CSR_INT_BIT_CT_KILL;
1034         }
1035
1036         /* Error detected by uCode */
1037         if (inta & CSR_INT_BIT_SW_ERR) {
1038                 IWL_ERR(trans, "Microcode SW error detected. "
1039                         " Restarting 0x%X.\n", inta);
1040                 isr_stats->sw++;
1041                 iwl_irq_handle_error(trans);
1042                 handled |= CSR_INT_BIT_SW_ERR;
1043         }
1044
1045         /* uCode wakes up after power-down sleep */
1046         if (inta & CSR_INT_BIT_WAKEUP) {
1047                 IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
1048                 iwl_rx_queue_update_write_ptr(trans, &trans_pcie->rxq);
1049                 for (i = 0; i < hw_params(trans).max_txq_num; i++)
1050                         iwl_txq_update_write_ptr(trans,
1051                                                  &trans_pcie->txq[i]);
1052
1053                 isr_stats->wakeup++;
1054
1055                 handled |= CSR_INT_BIT_WAKEUP;
1056         }
1057
1058         /* All uCode command responses, including Tx command responses,
1059          * Rx "responses" (frame-received notification), and other
1060          * notifications from uCode come through here*/
1061         if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX |
1062                         CSR_INT_BIT_RX_PERIODIC)) {
1063                 IWL_DEBUG_ISR(trans, "Rx interrupt\n");
1064                 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) {
1065                         handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX);
1066                         iwl_write32(bus(trans), CSR_FH_INT_STATUS,
1067                                         CSR_FH_INT_RX_MASK);
1068                 }
1069                 if (inta & CSR_INT_BIT_RX_PERIODIC) {
1070                         handled |= CSR_INT_BIT_RX_PERIODIC;
1071                         iwl_write32(bus(trans),
1072                                 CSR_INT, CSR_INT_BIT_RX_PERIODIC);
1073                 }
1074                 /* Sending RX interrupt require many steps to be done in the
1075                  * the device:
1076                  * 1- write interrupt to current index in ICT table.
1077                  * 2- dma RX frame.
1078                  * 3- update RX shared data to indicate last write index.
1079                  * 4- send interrupt.
1080                  * This could lead to RX race, driver could receive RX interrupt
1081                  * but the shared data changes does not reflect this;
1082                  * periodic interrupt will detect any dangling Rx activity.
1083                  */
1084
1085                 /* Disable periodic interrupt; we use it as just a one-shot. */
1086                 iwl_write8(bus(trans), CSR_INT_PERIODIC_REG,
1087                             CSR_INT_PERIODIC_DIS);
1088                 iwl_rx_handle(trans);
1089
1090                 /*
1091                  * Enable periodic interrupt in 8 msec only if we received
1092                  * real RX interrupt (instead of just periodic int), to catch
1093                  * any dangling Rx interrupt.  If it was just the periodic
1094                  * interrupt, there was no dangling Rx activity, and no need
1095                  * to extend the periodic interrupt; one-shot is enough.
1096                  */
1097                 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX))
1098                         iwl_write8(bus(trans), CSR_INT_PERIODIC_REG,
1099                                     CSR_INT_PERIODIC_ENA);
1100
1101                 isr_stats->rx++;
1102         }
1103
1104         /* This "Tx" DMA channel is used only for loading uCode */
1105         if (inta & CSR_INT_BIT_FH_TX) {
1106                 iwl_write32(bus(trans), CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
1107                 IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
1108                 isr_stats->tx++;
1109                 handled |= CSR_INT_BIT_FH_TX;
1110                 /* Wake up uCode load routine, now that load is complete */
1111                 priv(trans)->ucode_write_complete = 1;
1112                 wake_up(&trans->shrd->wait_command_queue);
1113         }
1114
1115         if (inta & ~handled) {
1116                 IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
1117                 isr_stats->unhandled++;
1118         }
1119
1120         if (inta & ~(trans_pcie->inta_mask)) {
1121                 IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n",
1122                          inta & ~trans_pcie->inta_mask);
1123         }
1124
1125         /* Re-enable all interrupts */
1126         /* only Re-enable if disabled by irq */
1127         if (test_bit(STATUS_INT_ENABLED, &trans->shrd->status))
1128                 iwl_enable_interrupts(trans);
1129         /* Re-enable RF_KILL if it occurred */
1130         else if (handled & CSR_INT_BIT_RF_KILL)
1131                 iwl_enable_rfkill_int(priv(trans));
1132 }
1133
1134 /******************************************************************************
1135  *
1136  * ICT functions
1137  *
1138  ******************************************************************************/
1139
1140 /* a device (PCI-E) page is 4096 bytes long */
1141 #define ICT_SHIFT       12
1142 #define ICT_SIZE        (1 << ICT_SHIFT)
1143 #define ICT_COUNT       (ICT_SIZE / sizeof(u32))
1144
1145 /* Free dram table */
1146 void iwl_free_isr_ict(struct iwl_trans *trans)
1147 {
1148         struct iwl_trans_pcie *trans_pcie =
1149                 IWL_TRANS_GET_PCIE_TRANS(trans);
1150
1151         if (trans_pcie->ict_tbl) {
1152                 dma_free_coherent(bus(trans)->dev, ICT_SIZE,
1153                                   trans_pcie->ict_tbl,
1154                                   trans_pcie->ict_tbl_dma);
1155                 trans_pcie->ict_tbl = NULL;
1156                 trans_pcie->ict_tbl_dma = 0;
1157         }
1158 }
1159
1160
1161 /*
1162  * allocate dram shared table, it is an aligned memory
1163  * block of ICT_SIZE.
1164  * also reset all data related to ICT table interrupt.
1165  */
1166 int iwl_alloc_isr_ict(struct iwl_trans *trans)
1167 {
1168         struct iwl_trans_pcie *trans_pcie =
1169                 IWL_TRANS_GET_PCIE_TRANS(trans);
1170
1171         trans_pcie->ict_tbl =
1172                 dma_alloc_coherent(bus(trans)->dev, ICT_SIZE,
1173                                    &trans_pcie->ict_tbl_dma,
1174                                    GFP_KERNEL);
1175         if (!trans_pcie->ict_tbl)
1176                 return -ENOMEM;
1177
1178         /* just an API sanity check ... it is guaranteed to be aligned */
1179         if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) {
1180                 iwl_free_isr_ict(trans);
1181                 return -EINVAL;
1182         }
1183
1184         IWL_DEBUG_ISR(trans, "ict dma addr %Lx\n",
1185                       (unsigned long long)trans_pcie->ict_tbl_dma);
1186
1187         IWL_DEBUG_ISR(trans, "ict vir addr %p\n", trans_pcie->ict_tbl);
1188
1189         /* reset table and index to all 0 */
1190         memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
1191         trans_pcie->ict_index = 0;
1192
1193         /* add periodic RX interrupt */
1194         trans_pcie->inta_mask |= CSR_INT_BIT_RX_PERIODIC;
1195         return 0;
1196 }
1197
1198 /* Device is going up inform it about using ICT interrupt table,
1199  * also we need to tell the driver to start using ICT interrupt.
1200  */
1201 int iwl_reset_ict(struct iwl_trans *trans)
1202 {
1203         u32 val;
1204         unsigned long flags;
1205         struct iwl_trans_pcie *trans_pcie =
1206                 IWL_TRANS_GET_PCIE_TRANS(trans);
1207
1208         if (!trans_pcie->ict_tbl)
1209                 return 0;
1210
1211         spin_lock_irqsave(&trans->shrd->lock, flags);
1212         iwl_disable_interrupts(trans);
1213
1214         memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
1215
1216         val = trans_pcie->ict_tbl_dma >> ICT_SHIFT;
1217
1218         val |= CSR_DRAM_INT_TBL_ENABLE;
1219         val |= CSR_DRAM_INIT_TBL_WRAP_CHECK;
1220
1221         IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val);
1222
1223         iwl_write32(bus(trans), CSR_DRAM_INT_TBL_REG, val);
1224         trans_pcie->use_ict = true;
1225         trans_pcie->ict_index = 0;
1226         iwl_write32(bus(trans), CSR_INT, trans_pcie->inta_mask);
1227         iwl_enable_interrupts(trans);
1228         spin_unlock_irqrestore(&trans->shrd->lock, flags);
1229
1230         return 0;
1231 }
1232
1233 /* Device is going down disable ict interrupt usage */
1234 void iwl_disable_ict(struct iwl_trans *trans)
1235 {
1236         struct iwl_trans_pcie *trans_pcie =
1237                 IWL_TRANS_GET_PCIE_TRANS(trans);
1238
1239         unsigned long flags;
1240
1241         spin_lock_irqsave(&trans->shrd->lock, flags);
1242         trans_pcie->use_ict = false;
1243         spin_unlock_irqrestore(&trans->shrd->lock, flags);
1244 }
1245
1246 static irqreturn_t iwl_isr(int irq, void *data)
1247 {
1248         struct iwl_trans *trans = data;
1249         struct iwl_trans_pcie *trans_pcie;
1250         u32 inta, inta_mask;
1251         unsigned long flags;
1252 #ifdef CONFIG_IWLWIFI_DEBUG
1253         u32 inta_fh;
1254 #endif
1255         if (!trans)
1256                 return IRQ_NONE;
1257
1258         trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1259
1260         spin_lock_irqsave(&trans->shrd->lock, flags);
1261
1262         /* Disable (but don't clear!) interrupts here to avoid
1263          *    back-to-back ISRs and sporadic interrupts from our NIC.
1264          * If we have something to service, the tasklet will re-enable ints.
1265          * If we *don't* have something, we'll re-enable before leaving here. */
1266         inta_mask = iwl_read32(bus(trans), CSR_INT_MASK);  /* just for debug */
1267         iwl_write32(bus(trans), CSR_INT_MASK, 0x00000000);
1268
1269         /* Discover which interrupts are active/pending */
1270         inta = iwl_read32(bus(trans), CSR_INT);
1271
1272         /* Ignore interrupt if there's nothing in NIC to service.
1273          * This may be due to IRQ shared with another device,
1274          * or due to sporadic interrupts thrown from our NIC. */
1275         if (!inta) {
1276                 IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1277                 goto none;
1278         }
1279
1280         if ((inta == 0xFFFFFFFF) || ((inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
1281                 /* Hardware disappeared. It might have already raised
1282                  * an interrupt */
1283                 IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta);
1284                 goto unplugged;
1285         }
1286
1287 #ifdef CONFIG_IWLWIFI_DEBUG
1288         if (iwl_get_debug_level(trans->shrd) & (IWL_DL_ISR)) {
1289                 inta_fh = iwl_read32(bus(trans), CSR_FH_INT_STATUS);
1290                 IWL_DEBUG_ISR(trans, "ISR inta 0x%08x, enabled 0x%08x, "
1291                               "fh 0x%08x\n", inta, inta_mask, inta_fh);
1292         }
1293 #endif
1294
1295         trans_pcie->inta |= inta;
1296         /* iwl_irq_tasklet() will service interrupts and re-enable them */
1297         if (likely(inta))
1298                 tasklet_schedule(&trans_pcie->irq_tasklet);
1299         else if (test_bit(STATUS_INT_ENABLED, &trans->shrd->status) &&
1300                         !trans_pcie->inta)
1301                 iwl_enable_interrupts(trans);
1302
1303  unplugged:
1304         spin_unlock_irqrestore(&trans->shrd->lock, flags);
1305         return IRQ_HANDLED;
1306
1307  none:
1308         /* re-enable interrupts here since we don't have anything to service. */
1309         /* only Re-enable if disabled by irq  and no schedules tasklet. */
1310         if (test_bit(STATUS_INT_ENABLED, &trans->shrd->status) &&
1311                 !trans_pcie->inta)
1312                 iwl_enable_interrupts(trans);
1313
1314         spin_unlock_irqrestore(&trans->shrd->lock, flags);
1315         return IRQ_NONE;
1316 }
1317
1318 /* interrupt handler using ict table, with this interrupt driver will
1319  * stop using INTA register to get device's interrupt, reading this register
1320  * is expensive, device will write interrupts in ICT dram table, increment
1321  * index then will fire interrupt to driver, driver will OR all ICT table
1322  * entries from current index up to table entry with 0 value. the result is
1323  * the interrupt we need to service, driver will set the entries back to 0 and
1324  * set index.
1325  */
1326 irqreturn_t iwl_isr_ict(int irq, void *data)
1327 {
1328         struct iwl_trans *trans = data;
1329         struct iwl_trans_pcie *trans_pcie;
1330         u32 inta, inta_mask;
1331         u32 val = 0;
1332         unsigned long flags;
1333
1334         if (!trans)
1335                 return IRQ_NONE;
1336
1337         trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1338
1339         /* dram interrupt table not set yet,
1340          * use legacy interrupt.
1341          */
1342         if (!trans_pcie->use_ict)
1343                 return iwl_isr(irq, data);
1344
1345         spin_lock_irqsave(&trans->shrd->lock, flags);
1346
1347         /* Disable (but don't clear!) interrupts here to avoid
1348          * back-to-back ISRs and sporadic interrupts from our NIC.
1349          * If we have something to service, the tasklet will re-enable ints.
1350          * If we *don't* have something, we'll re-enable before leaving here.
1351          */
1352         inta_mask = iwl_read32(bus(trans), CSR_INT_MASK);  /* just for debug */
1353         iwl_write32(bus(trans), CSR_INT_MASK, 0x00000000);
1354
1355
1356         /* Ignore interrupt if there's nothing in NIC to service.
1357          * This may be due to IRQ shared with another device,
1358          * or due to sporadic interrupts thrown from our NIC. */
1359         if (!trans_pcie->ict_tbl[trans_pcie->ict_index]) {
1360                 IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1361                 goto none;
1362         }
1363
1364         /* read all entries that not 0 start with ict_index */
1365         while (trans_pcie->ict_tbl[trans_pcie->ict_index]) {
1366
1367                 val |= le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1368                 IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n",
1369                                 trans_pcie->ict_index,
1370                                 le32_to_cpu(
1371                                   trans_pcie->ict_tbl[trans_pcie->ict_index]));
1372                 trans_pcie->ict_tbl[trans_pcie->ict_index] = 0;
1373                 trans_pcie->ict_index =
1374                         iwl_queue_inc_wrap(trans_pcie->ict_index, ICT_COUNT);
1375
1376         }
1377
1378         /* We should not get this value, just ignore it. */
1379         if (val == 0xffffffff)
1380                 val = 0;
1381
1382         /*
1383          * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit
1384          * (bit 15 before shifting it to 31) to clear when using interrupt
1385          * coalescing. fortunately, bits 18 and 19 stay set when this happens
1386          * so we use them to decide on the real state of the Rx bit.
1387          * In order words, bit 15 is set if bit 18 or bit 19 are set.
1388          */
1389         if (val & 0xC0000)
1390                 val |= 0x8000;
1391
1392         inta = (0xff & val) | ((0xff00 & val) << 16);
1393         IWL_DEBUG_ISR(trans, "ISR inta 0x%08x, enabled 0x%08x ict 0x%08x\n",
1394                         inta, inta_mask, val);
1395
1396         inta &= trans_pcie->inta_mask;
1397         trans_pcie->inta |= inta;
1398
1399         /* iwl_irq_tasklet() will service interrupts and re-enable them */
1400         if (likely(inta))
1401                 tasklet_schedule(&trans_pcie->irq_tasklet);
1402         else if (test_bit(STATUS_INT_ENABLED, &trans->shrd->status) &&
1403                         !trans_pcie->inta) {
1404                 /* Allow interrupt if was disabled by this handler and
1405                  * no tasklet was schedules, We should not enable interrupt,
1406                  * tasklet will enable it.
1407                  */
1408                 iwl_enable_interrupts(trans);
1409         }
1410
1411         spin_unlock_irqrestore(&trans->shrd->lock, flags);
1412         return IRQ_HANDLED;
1413
1414  none:
1415         /* re-enable interrupts here since we don't have anything to service.
1416          * only Re-enable if disabled by irq.
1417          */
1418         if (test_bit(STATUS_INT_ENABLED, &trans->shrd->status) &&
1419                 !trans_pcie->inta)
1420                 iwl_enable_interrupts(trans);
1421
1422         spin_unlock_irqrestore(&trans->shrd->lock, flags);
1423         return IRQ_NONE;
1424 }