drivers/net/wireless/intel/iwlwifi/pcie/rx.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2014 Intel Corporation. All rights reserved.
   4  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
   5  * Copyright(c) 2016 Intel Deutschland GmbH
   6  *
   7  * Portions of this file are derived from the ipw3945 project, as well
   8  * as portions of the ieee80211 subsystem header files.
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of version 2 of the GNU General Public License as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along with
  20  * this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  22  *
  23  * The full GNU General Public License is included in this distribution in the
  24  * file called LICENSE.
  25  *
  26  * Contact Information:
  27  *  Intel Linux Wireless <linuxwifi@intel.com>
  28  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  29  *
  30  *****************************************************************************/
  31 #include <linux/sched.h>
  32 #include <linux/wait.h>
  33 #include <linux/gfp.h>
  34
  35 #include "iwl-prph.h"
  36 #include "iwl-io.h"
  37 #include "internal.h"
  38 #include "iwl-op-mode.h"
  39
  40 /******************************************************************************
  41  *
  42  * RX path functions
  43  *
  44  ******************************************************************************/
  45
  46 /*
  47  * Rx theory of operation
  48  *
  49  * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
  50  * each of which point to Receive Buffers to be filled by the NIC.  These get
  51  * used not only for Rx frames, but for any command response or notification
  52  * from the NIC.  The driver and NIC manage the Rx buffers by means
  53  * of indexes into the circular buffer.
  54  *
  55  * Rx Queue Indexes
  56  * The host/firmware share two index registers for managing the Rx buffers.
  57  *
  58  * The READ index maps to the first position that the firmware may be writing
  59  * to -- the driver can read up to (but not including) this position and get
  60  * good data.
  61  * The READ index is managed by the firmware once the card is enabled.
  62  *
  63  * The WRITE index maps to the last position the driver has read from -- the
  64  * position preceding WRITE is the last slot the firmware can place a packet.
  65  *
  66  * The queue is empty (no good data) if WRITE = READ - 1, and is full if
  67  * WRITE = READ.
  68  *
  69  * During initialization, the host sets up the READ queue position to the first
  70  * INDEX position, and WRITE to the last (READ - 1 wrapped)
  71  *
  72  * When the firmware places a packet in a buffer, it will advance the READ index
  73  * and fire the RX interrupt.  The driver can then query the READ index and
  74  * process as many packets as possible, moving the WRITE index forward as it
  75  * resets the Rx queue buffers with new memory.
  76  *
  77  * The management in the driver is as follows:
  78  * + A list of pre-allocated RBDs is stored in iwl->rxq->rx_free.
  79  *   When the interrupt handler is called, the request is processed.
  80  *   The page is either stolen - transferred to the upper layer
  81  *   or reused - added immediately to the iwl->rxq->rx_free list.
  82  * + When the page is stolen - the driver updates the matching queue's used
  83  *   count, detaches the RBD and transfers it to the queue used list.
  84  *   When there are two used RBDs - they are transferred to the allocator empty
  85  *   list. Work is then scheduled for the allocator to start allocating
  86  *   eight buffers.
  87  *   When there are another 6 used RBDs - they are transferred to the allocator
  88  *   empty list and the driver tries to claim the pre-allocated buffers and
  89  *   add them to iwl->rxq->rx_free. If it fails - it continues to claim them
  90  *   until ready.
  91  *   When there are 8+ buffers in the free list - either from allocation or from
  92  *   8 reused unstolen pages - restock is called to update the FW and indexes.
  93  * + In order to make sure the allocator always has RBDs to use for allocation
  94  *   the allocator has initial pool in the size of num_queues*(8-2) - the
  95  *   maximum missing RBDs per allocation request (request posted with 2
  96  *    empty RBDs, there is no guarantee when the other 6 RBDs are supplied).
  97  *   The queues supplies the recycle of the rest of the RBDs.
  98  * + A received packet is processed and handed to the kernel network stack,
  99  *   detached from the iwl->rxq.  The driver 'processed' index is updated.
 100  * + If there are no allocated buffers in iwl->rxq->rx_free,
 101  *   the READ INDEX is not incremented and iwl->status(RX_STALLED) is set.
 102  *   If there were enough free buffers and RX_STALLED is set it is cleared.
 103  *
 104  *
 105  * Driver sequence:
 106  *
 107  * iwl_rxq_alloc()            Allocates rx_free
 108  * iwl_pcie_rx_replenish()    Replenishes rx_free list from rx_used, and calls
 109  *                            iwl_pcie_rxq_restock.
 110  *                            Used only during initialization.
 111  * iwl_pcie_rxq_restock()     Moves available buffers from rx_free into Rx
 112  *                            queue, updates firmware pointers, and updates
 113  *                            the WRITE index.
 114  * iwl_pcie_rx_allocator()     Background work for allocating pages.
 115  *
 116  * -- enable interrupts --
 117  * ISR - iwl_rx()             Detach iwl_rx_mem_buffers from pool up to the
 118  *                            READ INDEX, detaching the SKB from the pool.
 119  *                            Moves the packet buffer from queue to rx_used.
 120  *                            Posts and claims requests to the allocator.
 121  *                            Calls iwl_pcie_rxq_restock to refill any empty
 122  *                            slots.
 123  *
 124  * RBD life-cycle:
 125  *
 126  * Init:
 127  * rxq.pool -> rxq.rx_used -> rxq.rx_free -> rxq.queue
 128  *
 129  * Regular Receive interrupt:
 130  * Page Stolen:
 131  * rxq.queue -> rxq.rx_used -> allocator.rbd_empty ->
 132  * allocator.rbd_allocated -> rxq.rx_free -> rxq.queue
 133  * Page not Stolen:
 134  * rxq.queue -> rxq.rx_free -> rxq.queue
 135  * ...
 136  *
 137  */
 138
 139 /*
 140  * iwl_rxq_space - Return number of free slots available in queue.
 141  */
 142 static int iwl_rxq_space(const struct iwl_rxq *rxq)
 143 {
 144         /* Make sure rx queue size is a power of 2 */
 145         WARN_ON(rxq->queue_size & (rxq->queue_size - 1));
 146
 147         /*
 148          * There can be up to (RX_QUEUE_SIZE - 1) free slots, to avoid ambiguity
 149          * between empty and completely full queues.
 150          * The following is equivalent to modulo by RX_QUEUE_SIZE and is well
 151          * defined for negative dividends.
 152          */
 153         return (rxq->read - rxq->write - 1) & (rxq->queue_size - 1);
 154 }
 155
 156 /*
 157  * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
 158  */
 159 static inline __le32 iwl_pcie_dma_addr2rbd_ptr(dma_addr_t dma_addr)
 160 {
 161         return cpu_to_le32((u32)(dma_addr >> 8));
 162 }
 163
 164 /*
 165  * iwl_pcie_rx_stop - stops the Rx DMA
 166  */
 167 int iwl_pcie_rx_stop(struct iwl_trans *trans)
 168 {
 169         if (trans->cfg->mq_rx_supported) {
 170                 iwl_write_prph(trans, RFH_RXF_DMA_CFG, 0);
 171                 return iwl_poll_prph_bit(trans, RFH_GEN_STATUS,
 172                                            RXF_DMA_IDLE, RXF_DMA_IDLE, 1000);
 173         } else {
 174                 iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 175                 return iwl_poll_direct_bit(trans, FH_MEM_RSSR_RX_STATUS_REG,
 176                                            FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE,
 177                                            1000);
 178         }
 179 }
 180
 181 /*
 182  * iwl_pcie_rxq_inc_wr_ptr - Update the write pointer for the RX queue
 183  */
 184 static void iwl_pcie_rxq_inc_wr_ptr(struct iwl_trans *trans,
 185                                     struct iwl_rxq *rxq)
 186 {
 187         u32 reg;
 188
 189         lockdep_assert_held(&rxq->lock);
 190
 191         /*
 192          * explicitly wake up the NIC if:
 193          * 1. shadow registers aren't enabled
 194          * 2. there is a chance that the NIC is asleep
 195          */
 196         if (!trans->cfg->base_params->shadow_reg_enable &&
 197             test_bit(STATUS_TPOWER_PMI, &trans->status)) {
 198                 reg = iwl_read32(trans, CSR_UCODE_DRV_GP1);
 199
 200                 if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
 201                         IWL_DEBUG_INFO(trans, "Rx queue requesting wakeup, GP1 = 0x%x\n",
 202                                        reg);
 203                         iwl_set_bit(trans, CSR_GP_CNTRL,
 204                                     CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 205                         rxq->need_update = true;
 206                         return;
 207                 }
 208         }
 209
 210         rxq->write_actual = round_down(rxq->write, 8);
 211         if (trans->cfg->mq_rx_supported)
 212                 iwl_write32(trans, RFH_Q_FRBDCB_WIDX_TRG(rxq->id),
 213                             rxq->write_actual);
 214         else
 215                 iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, rxq->write_actual);
 216 }
 217
 218 static void iwl_pcie_rxq_check_wrptr(struct iwl_trans *trans)
 219 {
 220         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 221         int i;
 222
 223         for (i = 0; i < trans->num_rx_queues; i++) {
 224                 struct iwl_rxq *rxq = &trans_pcie->rxq[i];
 225
 226                 if (!rxq->need_update)
 227                         continue;
 228                 spin_lock(&rxq->lock);
 229                 iwl_pcie_rxq_inc_wr_ptr(trans, rxq);
 230                 rxq->need_update = false;
 231                 spin_unlock(&rxq->lock);
 232         }
 233 }
 234
 235 /*
 236  * iwl_pcie_rxmq_restock - restock implementation for multi-queue rx
 237  */
 238 static void iwl_pcie_rxmq_restock(struct iwl_trans *trans,
 239                                   struct iwl_rxq *rxq)
 240 {
 241         struct iwl_rx_mem_buffer *rxb;
 242
 243         /*
 244          * If the device isn't enabled - no need to try to add buffers...
 245          * This can happen when we stop the device and still have an interrupt
 246          * pending. We stop the APM before we sync the interrupts because we
 247          * have to (see comment there). On the other hand, since the APM is
 248          * stopped, we cannot access the HW (in particular not prph).
 249          * So don't try to restock if the APM has been already stopped.
 250          */
 251         if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
 252                 return;
 253
 254         spin_lock(&rxq->lock);
 255         while (rxq->free_count) {
 256                 __le64 *bd = (__le64 *)rxq->bd;
 257
 258                 /* Get next free Rx buffer, remove from free list */
 259                 rxb = list_first_entry(&rxq->rx_free, struct iwl_rx_mem_buffer,
 260                                        list);
 261                 list_del(&rxb->list);
 262                 rxb->invalid = false;
 263                 /* 12 first bits are expected to be empty */
 264                 WARN_ON(rxb->page_dma & DMA_BIT_MASK(12));
 265                 /* Point to Rx buffer via next RBD in circular buffer */
 266                 bd[rxq->write] = cpu_to_le64(rxb->page_dma | rxb->vid);
 267                 rxq->write = (rxq->write + 1) & MQ_RX_TABLE_MASK;
 268                 rxq->free_count--;
 269         }
 270         spin_unlock(&rxq->lock);
 271
 272         /*
 273          * If we've added more space for the firmware to place data, tell it.
 274          * Increment device's write pointer in multiples of 8.
 275          */
 276         if (rxq->write_actual != (rxq->write & ~0x7)) {
 277                 spin_lock(&rxq->lock);
 278                 iwl_pcie_rxq_inc_wr_ptr(trans, rxq);
 279                 spin_unlock(&rxq->lock);
 280         }
 281 }
 282
 283 /*
 284  * iwl_pcie_rxsq_restock - restock implementation for single queue rx
 285  */
 286 static void iwl_pcie_rxsq_restock(struct iwl_trans *trans,
 287                                   struct iwl_rxq *rxq)
 288 {
 289         struct iwl_rx_mem_buffer *rxb;
 290
 291         /*
 292          * If the device isn't enabled - not need to try to add buffers...
 293          * This can happen when we stop the device and still have an interrupt
 294          * pending. We stop the APM before we sync the interrupts because we
 295          * have to (see comment there). On the other hand, since the APM is
 296          * stopped, we cannot access the HW (in particular not prph).
 297          * So don't try to restock if the APM has been already stopped.
 298          */
 299         if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
 300                 return;
 301
 302         spin_lock(&rxq->lock);
 303         while ((iwl_rxq_space(rxq) > 0) && (rxq->free_count)) {
 304                 __le32 *bd = (__le32 *)rxq->bd;
 305                 /* The overwritten rxb must be a used one */
 306                 rxb = rxq->queue[rxq->write];
 307                 BUG_ON(rxb && rxb->page);
 308
 309                 /* Get next free Rx buffer, remove from free list */
 310                 rxb = list_first_entry(&rxq->rx_free, struct iwl_rx_mem_buffer,
 311                                        list);
 312                 list_del(&rxb->list);
 313                 rxb->invalid = false;
 314
 315                 /* Point to Rx buffer via next RBD in circular buffer */
 316                 bd[rxq->write] = iwl_pcie_dma_addr2rbd_ptr(rxb->page_dma);
 317                 rxq->queue[rxq->write] = rxb;
 318                 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
 319                 rxq->free_count--;
 320         }
 321         spin_unlock(&rxq->lock);
 322
 323         /* If we've added more space for the firmware to place data, tell it.
 324          * Increment device's write pointer in multiples of 8. */
 325         if (rxq->write_actual != (rxq->write & ~0x7)) {
 326                 spin_lock(&rxq->lock);
 327                 iwl_pcie_rxq_inc_wr_ptr(trans, rxq);
 328                 spin_unlock(&rxq->lock);
 329         }
 330 }
 331
 332 /*
 333  * iwl_pcie_rxq_restock - refill RX queue from pre-allocated pool
 334  *
 335  * If there are slots in the RX queue that need to be restocked,
 336  * and we have free pre-allocated buffers, fill the ranks as much
 337  * as we can, pulling from rx_free.
 338  *
 339  * This moves the 'write' index forward to catch up with 'processed', and
 340  * also updates the memory address in the firmware to reference the new
 341  * target buffer.
 342  */
 343 static
 344 void iwl_pcie_rxq_restock(struct iwl_trans *trans, struct iwl_rxq *rxq)
 345 {
 346         if (trans->cfg->mq_rx_supported)
 347                 iwl_pcie_rxmq_restock(trans, rxq);
 348         else
 349                 iwl_pcie_rxsq_restock(trans, rxq);
 350 }
 351
 352 /*
 353  * iwl_pcie_rx_alloc_page - allocates and returns a page.
 354  *
 355  */
 356 static struct page *iwl_pcie_rx_alloc_page(struct iwl_trans *trans,
 357                                            gfp_t priority)
 358 {
 359         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 360         struct page *page;
 361         gfp_t gfp_mask = priority;
 362
 363         if (trans_pcie->rx_page_order > 0)
 364                 gfp_mask |= __GFP_COMP;
 365
 366         /* Alloc a new receive buffer */
 367         page = alloc_pages(gfp_mask, trans_pcie->rx_page_order);
 368         if (!page) {
 369                 if (net_ratelimit())
 370                         IWL_DEBUG_INFO(trans, "alloc_pages failed, order: %d\n",
 371                                        trans_pcie->rx_page_order);
 372                 /*
 373                  * Issue an error if we don't have enough pre-allocated
 374                   * buffers.
 375 `                */
 376                 if (!(gfp_mask & __GFP_NOWARN) && net_ratelimit())
 377                         IWL_CRIT(trans,
 378                                  "Failed to alloc_pages\n");
 379                 return NULL;
 380         }
 381         return page;
 382 }
 383
 384 /*
 385  * iwl_pcie_rxq_alloc_rbs - allocate a page for each used RBD
 386  *
 387  * A used RBD is an Rx buffer that has been given to the stack. To use it again
 388  * a page must be allocated and the RBD must point to the page. This function
 389  * doesn't change the HW pointer but handles the list of pages that is used by
 390  * iwl_pcie_rxq_restock. The latter function will update the HW to use the newly
 391  * allocated buffers.
 392  */
 393 static void iwl_pcie_rxq_alloc_rbs(struct iwl_trans *trans, gfp_t priority,
 394                                    struct iwl_rxq *rxq)
 395 {
 396         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 397         struct iwl_rx_mem_buffer *rxb;
 398         struct page *page;
 399
 400         while (1) {
 401                 spin_lock(&rxq->lock);
 402                 if (list_empty(&rxq->rx_used)) {
 403                         spin_unlock(&rxq->lock);
 404                         return;
 405                 }
 406                 spin_unlock(&rxq->lock);
 407
 408                 /* Alloc a new receive buffer */
 409                 page = iwl_pcie_rx_alloc_page(trans, priority);
 410                 if (!page)
 411                         return;
 412
 413                 spin_lock(&rxq->lock);
 414
 415                 if (list_empty(&rxq->rx_used)) {
 416                         spin_unlock(&rxq->lock);
 417                         __free_pages(page, trans_pcie->rx_page_order);
 418                         return;
 419                 }
 420                 rxb = list_first_entry(&rxq->rx_used, struct iwl_rx_mem_buffer,
 421                                        list);
 422                 list_del(&rxb->list);
 423                 spin_unlock(&rxq->lock);
 424
 425                 BUG_ON(rxb->page);
 426                 rxb->page = page;
 427                 /* Get physical address of the RB */
 428                 rxb->page_dma =
 429                         dma_map_page(trans->dev, page, 0,
 430                                      PAGE_SIZE << trans_pcie->rx_page_order,
 431                                      DMA_FROM_DEVICE);
 432                 if (dma_mapping_error(trans->dev, rxb->page_dma)) {
 433                         rxb->page = NULL;
 434                         spin_lock(&rxq->lock);
 435                         list_add(&rxb->list, &rxq->rx_used);
 436                         spin_unlock(&rxq->lock);
 437                         __free_pages(page, trans_pcie->rx_page_order);
 438                         return;
 439                 }
 440
 441                 spin_lock(&rxq->lock);
 442
 443                 list_add_tail(&rxb->list, &rxq->rx_free);
 444                 rxq->free_count++;
 445
 446                 spin_unlock(&rxq->lock);
 447         }
 448 }
 449
 450 static void iwl_pcie_free_rbs_pool(struct iwl_trans *trans)
 451 {
 452         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 453         int i;
 454
 455         for (i = 0; i < RX_POOL_SIZE; i++) {
 456                 if (!trans_pcie->rx_pool[i].page)
 457                         continue;
 458                 dma_unmap_page(trans->dev, trans_pcie->rx_pool[i].page_dma,
 459                                PAGE_SIZE << trans_pcie->rx_page_order,
 460                                DMA_FROM_DEVICE);
 461                 __free_pages(trans_pcie->rx_pool[i].page,
 462                              trans_pcie->rx_page_order);
 463                 trans_pcie->rx_pool[i].page = NULL;
 464         }
 465 }
 466
 467 /*
 468  * iwl_pcie_rx_allocator - Allocates pages in the background for RX queues
 469  *
 470  * Allocates for each received request 8 pages
 471  * Called as a scheduled work item.
 472  */
 473 static void iwl_pcie_rx_allocator(struct iwl_trans *trans)
 474 {
 475         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 476         struct iwl_rb_allocator *rba = &trans_pcie->rba;
 477         struct list_head local_empty;
 478         int pending = atomic_xchg(&rba->req_pending, 0);
 479
 480         IWL_DEBUG_RX(trans, "Pending allocation requests = %d\n", pending);
 481
 482         /* If we were scheduled - there is at least one request */
 483         spin_lock(&rba->lock);
 484         /* swap out the rba->rbd_empty to a local list */
 485         list_replace_init(&rba->rbd_empty, &local_empty);
 486         spin_unlock(&rba->lock);
 487
 488         while (pending) {
 489                 int i;
 490                 struct list_head local_allocated;
 491                 gfp_t gfp_mask = GFP_KERNEL;
 492
 493                 /* Do not post a warning if there are only a few requests */
 494                 if (pending < RX_PENDING_WATERMARK)
 495                         gfp_mask |= __GFP_NOWARN;
 496
 497                 INIT_LIST_HEAD(&local_allocated);
 498
 499                 for (i = 0; i < RX_CLAIM_REQ_ALLOC;) {
 500                         struct iwl_rx_mem_buffer *rxb;
 501                         struct page *page;
 502
 503                         /* List should never be empty - each reused RBD is
 504                          * returned to the list, and initial pool covers any
 505                          * possible gap between the time the page is allocated
 506                          * to the time the RBD is added.
 507                          */
 508                         BUG_ON(list_empty(&local_empty));
 509                         /* Get the first rxb from the rbd list */
 510                         rxb = list_first_entry(&local_empty,
 511                                                struct iwl_rx_mem_buffer, list);
 512                         BUG_ON(rxb->page);
 513
 514                         /* Alloc a new receive buffer */
 515                         page = iwl_pcie_rx_alloc_page(trans, gfp_mask);
 516                         if (!page)
 517                                 continue;
 518                         rxb->page = page;
 519
 520                         /* Get physical address of the RB */
 521                         rxb->page_dma = dma_map_page(trans->dev, page, 0,
 522                                         PAGE_SIZE << trans_pcie->rx_page_order,
 523                                         DMA_FROM_DEVICE);
 524                         if (dma_mapping_error(trans->dev, rxb->page_dma)) {
 525                                 rxb->page = NULL;
 526                                 __free_pages(page, trans_pcie->rx_page_order);
 527                                 continue;
 528                         }
 529
 530                         /* move the allocated entry to the out list */
 531                         list_move(&rxb->list, &local_allocated);
 532                         i++;
 533                 }
 534
 535                 pending--;
 536                 if (!pending) {
 537                         pending = atomic_xchg(&rba->req_pending, 0);
 538                         IWL_DEBUG_RX(trans,
 539                                      "Pending allocation requests = %d\n",
 540                                      pending);
 541                 }
 542
 543                 spin_lock(&rba->lock);
 544                 /* add the allocated rbds to the allocator allocated list */
 545                 list_splice_tail(&local_allocated, &rba->rbd_allocated);
 546                 /* get more empty RBDs for current pending requests */
 547                 list_splice_tail_init(&rba->rbd_empty, &local_empty);
 548                 spin_unlock(&rba->lock);
 549
 550                 atomic_inc(&rba->req_ready);
 551         }
 552
 553         spin_lock(&rba->lock);
 554         /* return unused rbds to the allocator empty list */
 555         list_splice_tail(&local_empty, &rba->rbd_empty);
 556         spin_unlock(&rba->lock);
 557 }
 558
 559 /*
 560  * iwl_pcie_rx_allocator_get - returns the pre-allocated pages
 561 .*
 562 .* Called by queue when the queue posted allocation request and
 563  * has freed 8 RBDs in order to restock itself.
 564  * This function directly moves the allocated RBs to the queue's ownership
 565  * and updates the relevant counters.
 566  */
 567 static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans,
 568                                       struct iwl_rxq *rxq)
 569 {
 570         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 571         struct iwl_rb_allocator *rba = &trans_pcie->rba;
 572         int i;
 573
 574         lockdep_assert_held(&rxq->lock);
 575
 576         /*
 577          * atomic_dec_if_positive returns req_ready - 1 for any scenario.
 578          * If req_ready is 0 atomic_dec_if_positive will return -1 and this
 579          * function will return early, as there are no ready requests.
 580          * atomic_dec_if_positive will perofrm the *actual* decrement only if
 581          * req_ready > 0, i.e. - there are ready requests and the function
 582          * hands one request to the caller.
 583          */
 584         if (atomic_dec_if_positive(&rba->req_ready) < 0)
 585                 return;
 586
 587         spin_lock(&rba->lock);
 588         for (i = 0; i < RX_CLAIM_REQ_ALLOC; i++) {
 589                 /* Get next free Rx buffer, remove it from free list */
 590                 struct iwl_rx_mem_buffer *rxb =
 591                         list_first_entry(&rba->rbd_allocated,
 592                                          struct iwl_rx_mem_buffer, list);
 593
 594                 list_move(&rxb->list, &rxq->rx_free);
 595         }
 596         spin_unlock(&rba->lock);
 597
 598         rxq->used_count -= RX_CLAIM_REQ_ALLOC;
 599         rxq->free_count += RX_CLAIM_REQ_ALLOC;
 600 }
 601
 602 static void iwl_pcie_rx_allocator_work(struct work_struct *data)
 603 {
 604         struct iwl_rb_allocator *rba_p =
 605                 container_of(data, struct iwl_rb_allocator, rx_alloc);
 606         struct iwl_trans_pcie *trans_pcie =
 607                 container_of(rba_p, struct iwl_trans_pcie, rba);
 608
 609         iwl_pcie_rx_allocator(trans_pcie->trans);
 610 }
 611
 612 static int iwl_pcie_rx_alloc(struct iwl_trans *trans)
 613 {
 614         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 615         struct iwl_rb_allocator *rba = &trans_pcie->rba;
 616         struct device *dev = trans->dev;
 617         int i;
 618         int free_size = trans->cfg->mq_rx_supported ? sizeof(__le64) :
 619                                                       sizeof(__le32);
 620
 621         if (WARN_ON(trans_pcie->rxq))
 622                 return -EINVAL;
 623
 624         trans_pcie->rxq = kcalloc(trans->num_rx_queues, sizeof(struct iwl_rxq),
 625                                   GFP_KERNEL);
 626         if (!trans_pcie->rxq)
 627                 return -EINVAL;
 628
 629         spin_lock_init(&rba->lock);
 630
 631         for (i = 0; i < trans->num_rx_queues; i++) {
 632                 struct iwl_rxq *rxq = &trans_pcie->rxq[i];
 633
 634                 spin_lock_init(&rxq->lock);
 635                 if (trans->cfg->mq_rx_supported)
 636                         rxq->queue_size = MQ_RX_TABLE_SIZE;
 637                 else
 638                         rxq->queue_size = RX_QUEUE_SIZE;
 639
 640                 /*
 641                  * Allocate the circular buffer of Read Buffer Descriptors
 642                  * (RBDs)
 643                  */
 644                 rxq->bd = dma_zalloc_coherent(dev,
 645                                              free_size * rxq->queue_size,
 646                                              &rxq->bd_dma, GFP_KERNEL);
 647                 if (!rxq->bd)
 648                         goto err;
 649
 650                 if (trans->cfg->mq_rx_supported) {
 651                         rxq->used_bd = dma_zalloc_coherent(dev,
 652                                                            sizeof(__le32) *
 653                                                            rxq->queue_size,
 654                                                            &rxq->used_bd_dma,
 655                                                            GFP_KERNEL);
 656                         if (!rxq->used_bd)
 657                                 goto err;
 658                 }
 659
 660                 /*Allocate the driver's pointer to receive buffer status */
 661                 rxq->rb_stts = dma_zalloc_coherent(dev, sizeof(*rxq->rb_stts),
 662                                                    &rxq->rb_stts_dma,
 663                                                    GFP_KERNEL);
 664                 if (!rxq->rb_stts)
 665                         goto err;
 666         }
 667         return 0;
 668
 669 err:
 670         for (i = 0; i < trans->num_rx_queues; i++) {
 671                 struct iwl_rxq *rxq = &trans_pcie->rxq[i];
 672
 673                 if (rxq->bd)
 674                         dma_free_coherent(dev, free_size * rxq->queue_size,
 675                                           rxq->bd, rxq->bd_dma);
 676                 rxq->bd_dma = 0;
 677                 rxq->bd = NULL;
 678
 679                 if (rxq->rb_stts)
 680                         dma_free_coherent(trans->dev,
 681                                           sizeof(struct iwl_rb_status),
 682                                           rxq->rb_stts, rxq->rb_stts_dma);
 683
 684                 if (rxq->used_bd)
 685                         dma_free_coherent(dev, sizeof(__le32) * rxq->queue_size,
 686                                           rxq->used_bd, rxq->used_bd_dma);
 687                 rxq->used_bd_dma = 0;
 688                 rxq->used_bd = NULL;
 689         }
 690         kfree(trans_pcie->rxq);
 691
 692         return -ENOMEM;
 693 }
 694
 695 static void iwl_pcie_rx_hw_init(struct iwl_trans *trans, struct iwl_rxq *rxq)
 696 {
 697         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 698         u32 rb_size;
 699         unsigned long flags;
 700         const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
 701
 702         switch (trans_pcie->rx_buf_size) {
 703         case IWL_AMSDU_4K:
 704                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
 705                 break;
 706         case IWL_AMSDU_8K:
 707                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
 708                 break;
 709         case IWL_AMSDU_12K:
 710                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_12K;
 711                 break;
 712         default:
 713                 WARN_ON(1);
 714                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
 715         }
 716
 717         if (!iwl_trans_grab_nic_access(trans, &flags))
 718                 return;
 719
 720         /* Stop Rx DMA */
 721         iwl_write32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 722         /* reset and flush pointers */
 723         iwl_write32(trans, FH_MEM_RCSR_CHNL0_RBDCB_WPTR, 0);
 724         iwl_write32(trans, FH_MEM_RCSR_CHNL0_FLUSH_RB_REQ, 0);
 725         iwl_write32(trans, FH_RSCSR_CHNL0_RDPTR, 0);
 726
 727         /* Reset driver's Rx queue write index */
 728         iwl_write32(trans, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
 729
 730         /* Tell device where to find RBD circular buffer in DRAM */
 731         iwl_write32(trans, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
 732                     (u32)(rxq->bd_dma >> 8));
 733
 734         /* Tell device where in DRAM to update its Rx status */
 735         iwl_write32(trans, FH_RSCSR_CHNL0_STTS_WPTR_REG,
 736                     rxq->rb_stts_dma >> 4);
 737
 738         /* Enable Rx DMA
 739          * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in
 740          *      the credit mechanism in 5000 HW RX FIFO
 741          * Direct rx interrupts to hosts
 742          * Rx buffer size 4 or 8k or 12k
 743          * RB timeout 0x10
 744          * 256 RBDs
 745          */
 746         iwl_write32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG,
 747                     FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
 748                     FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY |
 749                     FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
 750                     rb_size |
 751                     (RX_RB_TIMEOUT << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS) |
 752                     (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));
 753
 754         iwl_trans_release_nic_access(trans, &flags);
 755
 756         /* Set interrupt coalescing timer to default (2048 usecs) */
 757         iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
 758
 759         /* W/A for interrupt coalescing bug in 7260 and 3160 */
 760         if (trans->cfg->host_interrupt_operation_mode)
 761                 iwl_set_bit(trans, CSR_INT_COALESCING, IWL_HOST_INT_OPER_MODE);
 762 }
 763
 764 void iwl_pcie_enable_rx_wake(struct iwl_trans *trans, bool enable)
 765 {
 766         /*
 767          * Turn on the chicken-bits that cause MAC wakeup for RX-related
 768          * values.
 769          * This costs some power, but needed for W/A 9000 integrated A-step
 770          * bug where shadow registers are not in the retention list and their
 771          * value is lost when NIC powers down
 772          */
 773         if (trans->cfg->integrated) {
 774                 iwl_set_bit(trans, CSR_MAC_SHADOW_REG_CTRL,
 775                             CSR_MAC_SHADOW_REG_CTRL_RX_WAKE);
 776                 iwl_set_bit(trans, CSR_MAC_SHADOW_REG_CTL2,
 777                             CSR_MAC_SHADOW_REG_CTL2_RX_WAKE);
 778         }
 779 }
 780
 781 static void iwl_pcie_rx_mq_hw_init(struct iwl_trans *trans)
 782 {
 783         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 784         u32 rb_size, enabled = 0;
 785         unsigned long flags;
 786         int i;
 787
 788         switch (trans_pcie->rx_buf_size) {
 789         case IWL_AMSDU_4K:
 790                 rb_size = RFH_RXF_DMA_RB_SIZE_4K;
 791                 break;
 792         case IWL_AMSDU_8K:
 793                 rb_size = RFH_RXF_DMA_RB_SIZE_8K;
 794                 break;
 795         case IWL_AMSDU_12K:
 796                 rb_size = RFH_RXF_DMA_RB_SIZE_12K;
 797                 break;
 798         default:
 799                 WARN_ON(1);
 800                 rb_size = RFH_RXF_DMA_RB_SIZE_4K;
 801         }
 802
 803         if (!iwl_trans_grab_nic_access(trans, &flags))
 804                 return;
 805
 806         /* Stop Rx DMA */
 807         iwl_write_prph_no_grab(trans, RFH_RXF_DMA_CFG, 0);
 808         /* disable free amd used rx queue operation */
 809         iwl_write_prph_no_grab(trans, RFH_RXF_RXQ_ACTIVE, 0);
 810
 811         for (i = 0; i < trans->num_rx_queues; i++) {
 812                 /* Tell device where to find RBD free table in DRAM */
 813                 iwl_write_prph64_no_grab(trans,
 814                                          RFH_Q_FRBDCB_BA_LSB(i),
 815                                          trans_pcie->rxq[i].bd_dma);
 816                 /* Tell device where to find RBD used table in DRAM */
 817                 iwl_write_prph64_no_grab(trans,
 818                                          RFH_Q_URBDCB_BA_LSB(i),
 819                                          trans_pcie->rxq[i].used_bd_dma);
 820                 /* Tell device where in DRAM to update its Rx status */
 821                 iwl_write_prph64_no_grab(trans,
 822                                          RFH_Q_URBD_STTS_WPTR_LSB(i),
 823                                          trans_pcie->rxq[i].rb_stts_dma);
 824                 /* Reset device indice tables */
 825                 iwl_write_prph_no_grab(trans, RFH_Q_FRBDCB_WIDX(i), 0);
 826                 iwl_write_prph_no_grab(trans, RFH_Q_FRBDCB_RIDX(i), 0);
 827                 iwl_write_prph_no_grab(trans, RFH_Q_URBDCB_WIDX(i), 0);
 828
 829                 enabled |= BIT(i) | BIT(i + 16);
 830         }
 831
 832         /*
 833          * Enable Rx DMA
 834          * Rx buffer size 4 or 8k or 12k
 835          * Min RB size 4 or 8
 836          * Drop frames that exceed RB size
 837          * 512 RBDs
 838          */
 839         iwl_write_prph_no_grab(trans, RFH_RXF_DMA_CFG,
 840                                RFH_DMA_EN_ENABLE_VAL | rb_size |
 841                                RFH_RXF_DMA_MIN_RB_4_8 |
 842                                RFH_RXF_DMA_DROP_TOO_LARGE_MASK |
 843                                RFH_RXF_DMA_RBDCB_SIZE_512);
 844
 845         /*
 846          * Activate DMA snooping.
 847          * Set RX DMA chunk size to 64B for IOSF and 128B for PCIe
 848          * Default queue is 0
 849          */
 850         iwl_write_prph_no_grab(trans, RFH_GEN_CFG, RFH_GEN_CFG_RFH_DMA_SNOOP |
 851                                (DEFAULT_RXQ_NUM <<
 852                                 RFH_GEN_CFG_DEFAULT_RXQ_NUM_POS) |
 853                                RFH_GEN_CFG_SERVICE_DMA_SNOOP |
 854                                (trans->cfg->integrated ?
 855                                 RFH_GEN_CFG_RB_CHUNK_SIZE_64 :
 856                                 RFH_GEN_CFG_RB_CHUNK_SIZE_128) <<
 857                                RFH_GEN_CFG_RB_CHUNK_SIZE_POS);
 858         /* Enable the relevant rx queues */
 859         iwl_write_prph_no_grab(trans, RFH_RXF_RXQ_ACTIVE, enabled);
 860
 861         iwl_trans_release_nic_access(trans, &flags);
 862
 863         /* Set interrupt coalescing timer to default (2048 usecs) */
 864         iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
 865
 866         iwl_pcie_enable_rx_wake(trans, true);
 867 }
 868
 869 static void iwl_pcie_rx_init_rxb_lists(struct iwl_rxq *rxq)
 870 {
 871         lockdep_assert_held(&rxq->lock);
 872
 873         INIT_LIST_HEAD(&rxq->rx_free);
 874         INIT_LIST_HEAD(&rxq->rx_used);
 875         rxq->free_count = 0;
 876         rxq->used_count = 0;
 877 }
 878
 879 static int iwl_pcie_dummy_napi_poll(struct napi_struct *napi, int budget)
 880 {
 881         WARN_ON(1);
 882         return 0;
 883 }
 884
 885 int iwl_pcie_rx_init(struct iwl_trans *trans)
 886 {
 887         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 888         struct iwl_rxq *def_rxq;
 889         struct iwl_rb_allocator *rba = &trans_pcie->rba;
 890         int i, err, queue_size, allocator_pool_size, num_alloc;
 891
 892         if (!trans_pcie->rxq) {
 893                 err = iwl_pcie_rx_alloc(trans);
 894                 if (err)
 895                         return err;
 896         }
 897         def_rxq = trans_pcie->rxq;
 898         if (!rba->alloc_wq)
 899                 rba->alloc_wq = alloc_workqueue("rb_allocator",
 900                                                 WQ_HIGHPRI | WQ_UNBOUND, 1);
 901         INIT_WORK(&rba->rx_alloc, iwl_pcie_rx_allocator_work);
 902
 903         spin_lock(&rba->lock);
 904         atomic_set(&rba->req_pending, 0);
 905         atomic_set(&rba->req_ready, 0);
 906         INIT_LIST_HEAD(&rba->rbd_allocated);
 907         INIT_LIST_HEAD(&rba->rbd_empty);
 908         spin_unlock(&rba->lock);
 909
 910         /* free all first - we might be reconfigured for a different size */
 911         iwl_pcie_free_rbs_pool(trans);
 912
 913         for (i = 0; i < RX_QUEUE_SIZE; i++)
 914                 def_rxq->queue[i] = NULL;
 915
 916         for (i = 0; i < trans->num_rx_queues; i++) {
 917                 struct iwl_rxq *rxq = &trans_pcie->rxq[i];
 918
 919                 rxq->id = i;
 920
 921                 spin_lock(&rxq->lock);
 922                 /*
 923                  * Set read write pointer to reflect that we have processed
 924                  * and used all buffers, but have not restocked the Rx queue
 925                  * with fresh buffers
 926                  */
 927                 rxq->read = 0;
 928                 rxq->write = 0;
 929                 rxq->write_actual = 0;
 930                 memset(rxq->rb_stts, 0, sizeof(*rxq->rb_stts));
 931
 932                 iwl_pcie_rx_init_rxb_lists(rxq);
 933
 934                 if (!rxq->napi.poll)
 935                         netif_napi_add(&trans_pcie->napi_dev, &rxq->napi,
 936                                        iwl_pcie_dummy_napi_poll, 64);
 937
 938                 spin_unlock(&rxq->lock);
 939         }
 940
 941         /* move the pool to the default queue and allocator ownerships */
 942         queue_size = trans->cfg->mq_rx_supported ?
 943                      MQ_RX_NUM_RBDS : RX_QUEUE_SIZE;
 944         allocator_pool_size = trans->num_rx_queues *
 945                 (RX_CLAIM_REQ_ALLOC - RX_POST_REQ_ALLOC);
 946         num_alloc = queue_size + allocator_pool_size;
 947         BUILD_BUG_ON(ARRAY_SIZE(trans_pcie->global_table) !=
 948                      ARRAY_SIZE(trans_pcie->rx_pool));
 949         for (i = 0; i < num_alloc; i++) {
 950                 struct iwl_rx_mem_buffer *rxb = &trans_pcie->rx_pool[i];
 951
 952                 if (i < allocator_pool_size)
 953                         list_add(&rxb->list, &rba->rbd_empty);
 954                 else
 955                         list_add(&rxb->list, &def_rxq->rx_used);
 956                 trans_pcie->global_table[i] = rxb;
 957                 rxb->vid = (u16)(i + 1);
 958                 rxb->invalid = true;
 959         }
 960
 961         iwl_pcie_rxq_alloc_rbs(trans, GFP_KERNEL, def_rxq);
 962
 963         if (trans->cfg->mq_rx_supported)
 964                 iwl_pcie_rx_mq_hw_init(trans);
 965         else
 966                 iwl_pcie_rx_hw_init(trans, def_rxq);
 967
 968         iwl_pcie_rxq_restock(trans, def_rxq);
 969
 970         spin_lock(&def_rxq->lock);
 971         iwl_pcie_rxq_inc_wr_ptr(trans, def_rxq);
 972         spin_unlock(&def_rxq->lock);
 973
 974         return 0;
 975 }
 976
 977 void iwl_pcie_rx_free(struct iwl_trans *trans)
 978 {
 979         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
 980         struct iwl_rb_allocator *rba = &trans_pcie->rba;
 981         int free_size = trans->cfg->mq_rx_supported ? sizeof(__le64) :
 982                                               sizeof(__le32);
 983         int i;
 984
 985         /*
 986          * if rxq is NULL, it means that nothing has been allocated,
 987          * exit now
 988          */
 989         if (!trans_pcie->rxq) {
 990                 IWL_DEBUG_INFO(trans, "Free NULL rx context\n");
 991                 return;
 992         }
 993
 994         cancel_work_sync(&rba->rx_alloc);
 995         if (rba->alloc_wq) {
 996                 destroy_workqueue(rba->alloc_wq);
 997                 rba->alloc_wq = NULL;
 998         }
 999
1000         iwl_pcie_free_rbs_pool(trans);
1001
1002         for (i = 0; i < trans->num_rx_queues; i++) {
1003                 struct iwl_rxq *rxq = &trans_pcie->rxq[i];
1004
1005                 if (rxq->bd)
1006                         dma_free_coherent(trans->dev,
1007                                           free_size * rxq->queue_size,
1008                                           rxq->bd, rxq->bd_dma);
1009                 rxq->bd_dma = 0;
1010                 rxq->bd = NULL;
1011
1012                 if (rxq->rb_stts)
1013                         dma_free_coherent(trans->dev,
1014                                           sizeof(struct iwl_rb_status),
1015                                           rxq->rb_stts, rxq->rb_stts_dma);
1016                 else
1017                         IWL_DEBUG_INFO(trans,
1018                                        "Free rxq->rb_stts which is NULL\n");
1019
1020                 if (rxq->used_bd)
1021                         dma_free_coherent(trans->dev,
1022                                           sizeof(__le32) * rxq->queue_size,
1023                                           rxq->used_bd, rxq->used_bd_dma);
1024                 rxq->used_bd_dma = 0;
1025                 rxq->used_bd = NULL;
1026
1027                 if (rxq->napi.poll)
1028                         netif_napi_del(&rxq->napi);
1029         }
1030         kfree(trans_pcie->rxq);
1031 }
1032
1033 /*
1034  * iwl_pcie_rx_reuse_rbd - Recycle used RBDs
1035  *
1036  * Called when a RBD can be reused. The RBD is transferred to the allocator.
1037  * When there are 2 empty RBDs - a request for allocation is posted
1038  */
1039 static void iwl_pcie_rx_reuse_rbd(struct iwl_trans *trans,
1040                                   struct iwl_rx_mem_buffer *rxb,
1041                                   struct iwl_rxq *rxq, bool emergency)
1042 {
1043         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1044         struct iwl_rb_allocator *rba = &trans_pcie->rba;
1045
1046         /* Move the RBD to the used list, will be moved to allocator in batches
1047          * before claiming or posting a request*/
1048         list_add_tail(&rxb->list, &rxq->rx_used);
1049
1050         if (unlikely(emergency))
1051                 return;
1052
1053         /* Count the allocator owned RBDs */
1054         rxq->used_count++;
1055
1056         /* If we have RX_POST_REQ_ALLOC new released rx buffers -
1057          * issue a request for allocator. Modulo RX_CLAIM_REQ_ALLOC is
1058          * used for the case we failed to claim RX_CLAIM_REQ_ALLOC,
1059          * after but we still need to post another request.
1060          */
1061         if ((rxq->used_count % RX_CLAIM_REQ_ALLOC) == RX_POST_REQ_ALLOC) {
1062                 /* Move the 2 RBDs to the allocator ownership.
1063                  Allocator has another 6 from pool for the request completion*/
1064                 spin_lock(&rba->lock);
1065                 list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty);
1066                 spin_unlock(&rba->lock);
1067
1068                 atomic_inc(&rba->req_pending);
1069                 queue_work(rba->alloc_wq, &rba->rx_alloc);
1070         }
1071 }
1072
1073 static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
1074                                 struct iwl_rxq *rxq,
1075                                 struct iwl_rx_mem_buffer *rxb,
1076                                 bool emergency)
1077 {
1078         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1079         struct iwl_txq *txq = &trans_pcie->txq[trans_pcie->cmd_queue];
1080         bool page_stolen = false;
1081         int max_len = PAGE_SIZE << trans_pcie->rx_page_order;
1082         u32 offset = 0;
1083
1084         if (WARN_ON(!rxb))
1085                 return;
1086
1087         dma_unmap_page(trans->dev, rxb->page_dma, max_len, DMA_FROM_DEVICE);
1088
1089         while (offset + sizeof(u32) + sizeof(struct iwl_cmd_header) < max_len) {
1090                 struct iwl_rx_packet *pkt;
1091                 u16 sequence;
1092                 bool reclaim;
1093                 int index, cmd_index, len;
1094                 struct iwl_rx_cmd_buffer rxcb = {
1095                         ._offset = offset,
1096                         ._rx_page_order = trans_pcie->rx_page_order,
1097                         ._page = rxb->page,
1098                         ._page_stolen = false,
1099                         .truesize = max_len,
1100                 };
1101
1102                 pkt = rxb_addr(&rxcb);
1103
1104                 if (pkt->len_n_flags == cpu_to_le32(FH_RSCSR_FRAME_INVALID))
1105                         break;
1106
1107                 WARN_ON((le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_RXQ_MASK) >>
1108                         FH_RSCSR_RXQ_POS != rxq->id);
1109
1110                 IWL_DEBUG_RX(trans,
1111                              "cmd at offset %d: %s (%.2x.%2x, seq 0x%x)\n",
1112                              rxcb._offset,
1113                              iwl_get_cmd_string(trans,
1114                                                 iwl_cmd_id(pkt->hdr.cmd,
1115                                                            pkt->hdr.group_id,
1116                                                            0)),
1117                              pkt->hdr.group_id, pkt->hdr.cmd,
1118                              le16_to_cpu(pkt->hdr.sequence));
1119
1120                 len = iwl_rx_packet_len(pkt);
1121                 len += sizeof(u32); /* account for status word */
1122                 trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len);
1123                 trace_iwlwifi_dev_rx_data(trans->dev, trans, pkt, len);
1124
1125                 /* Reclaim a command buffer only if this packet is a response
1126                  *   to a (driver-originated) command.
1127                  * If the packet (e.g. Rx frame) originated from uCode,
1128                  *   there is no command buffer to reclaim.
1129                  * Ucode should set SEQ_RX_FRAME bit if ucode-originated,
1130                  *   but apparently a few don't get set; catch them here. */
1131                 reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME);
1132                 if (reclaim) {
1133                         int i;
1134
1135                         for (i = 0; i < trans_pcie->n_no_reclaim_cmds; i++) {
1136                                 if (trans_pcie->no_reclaim_cmds[i] ==
1137                                                         pkt->hdr.cmd) {
1138                                         reclaim = false;
1139                                         break;
1140                                 }
1141                         }
1142                 }
1143
1144                 sequence = le16_to_cpu(pkt->hdr.sequence);
1145                 index = SEQ_TO_INDEX(sequence);
1146                 cmd_index = get_cmd_index(txq, index);
1147
1148                 if (rxq->id == 0)
1149                         iwl_op_mode_rx(trans->op_mode, &rxq->napi,
1150                                        &rxcb);
1151                 else
1152                         iwl_op_mode_rx_rss(trans->op_mode, &rxq->napi,
1153                                            &rxcb, rxq->id);
1154
1155                 if (reclaim) {
1156                         kzfree(txq->entries[cmd_index].free_buf);
1157                         txq->entries[cmd_index].free_buf = NULL;
1158                 }
1159
1160                 /*
1161                  * After here, we should always check rxcb._page_stolen,
1162                  * if it is true then one of the handlers took the page.
1163                  */
1164
1165                 if (reclaim) {
1166                         /* Invoke any callbacks, transfer the buffer to caller,
1167                          * and fire off the (possibly) blocking
1168                          * iwl_trans_send_cmd()
1169                          * as we reclaim the driver command queue */
1170                         if (!rxcb._page_stolen)
1171                                 iwl_pcie_hcmd_complete(trans, &rxcb);
1172                         else
1173                                 IWL_WARN(trans, "Claim null rxb?\n");
1174                 }
1175
1176                 page_stolen |= rxcb._page_stolen;
1177                 offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
1178         }
1179
1180         /* page was stolen from us -- free our reference */
1181         if (page_stolen) {
1182                 __free_pages(rxb->page, trans_pcie->rx_page_order);
1183                 rxb->page = NULL;
1184         }
1185
1186         /* Reuse the page if possible. For notification packets and
1187          * SKBs that fail to Rx correctly, add them back into the
1188          * rx_free list for reuse later. */
1189         if (rxb->page != NULL) {
1190                 rxb->page_dma =
1191                         dma_map_page(trans->dev, rxb->page, 0,
1192                                      PAGE_SIZE << trans_pcie->rx_page_order,
1193                                      DMA_FROM_DEVICE);
1194                 if (dma_mapping_error(trans->dev, rxb->page_dma)) {
1195                         /*
1196                          * free the page(s) as well to not break
1197                          * the invariant that the items on the used
1198                          * list have no page(s)
1199                          */
1200                         __free_pages(rxb->page, trans_pcie->rx_page_order);
1201                         rxb->page = NULL;
1202                         iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
1203                 } else {
1204                         list_add_tail(&rxb->list, &rxq->rx_free);
1205                         rxq->free_count++;
1206                 }
1207         } else
1208                 iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
1209 }
1210
1211 /*
1212  * iwl_pcie_rx_handle - Main entry function for receiving responses from fw
1213  */
1214 static void iwl_pcie_rx_handle(struct iwl_trans *trans, int queue)
1215 {
1216         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1217         struct iwl_rxq *rxq = &trans_pcie->rxq[queue];
1218         u32 r, i, count = 0;
1219         bool emergency = false;
1220
1221 restart:
1222         spin_lock(&rxq->lock);
1223         /* uCode's read index (stored in shared DRAM) indicates the last Rx
1224          * buffer that the driver may process (last buffer filled by ucode). */
1225         r = le16_to_cpu(ACCESS_ONCE(rxq->rb_stts->closed_rb_num)) & 0x0FFF;
1226         i = rxq->read;
1227
1228         /* W/A 9000 device step A0 wrap-around bug */
1229         r &= (rxq->queue_size - 1);
1230
1231         /* Rx interrupt, but nothing sent from uCode */
1232         if (i == r)
1233                 IWL_DEBUG_RX(trans, "Q %d: HW = SW = %d\n", rxq->id, r);
1234
1235         while (i != r) {
1236                 struct iwl_rx_mem_buffer *rxb;
1237
1238                 if (unlikely(rxq->used_count == rxq->queue_size / 2))
1239                         emergency = true;
1240
1241                 if (trans->cfg->mq_rx_supported) {
1242                         /*
1243                          * used_bd is a 32 bit but only 12 are used to retrieve
1244                          * the vid
1245                          */
1246                         u16 vid = le32_to_cpu(rxq->used_bd[i]) & 0x0FFF;
1247
1248                         if (WARN(!vid ||
1249                                  vid > ARRAY_SIZE(trans_pcie->global_table),
1250                                  "Invalid rxb index from HW %u\n", (u32)vid)) {
1251                                 iwl_force_nmi(trans);
1252                                 goto out;
1253                         }
1254                         rxb = trans_pcie->global_table[vid - 1];
1255                         if (WARN(rxb->invalid,
1256                                  "Invalid rxb from HW %u\n", (u32)vid)) {
1257                                 iwl_force_nmi(trans);
1258                                 goto out;
1259                         }
1260                         rxb->invalid = true;
1261                 } else {
1262                         rxb = rxq->queue[i];
1263                         rxq->queue[i] = NULL;
1264                 }
1265
1266                 IWL_DEBUG_RX(trans, "Q %d: HW = %d, SW = %d\n", rxq->id, r, i);
1267                 iwl_pcie_rx_handle_rb(trans, rxq, rxb, emergency);
1268
1269                 i = (i + 1) & (rxq->queue_size - 1);
1270
1271                 /*
1272                  * If we have RX_CLAIM_REQ_ALLOC released rx buffers -
1273                  * try to claim the pre-allocated buffers from the allocator.
1274                  * If not ready - will try to reclaim next time.
1275                  * There is no need to reschedule work - allocator exits only
1276                  * on success
1277                  */
1278                 if (rxq->used_count >= RX_CLAIM_REQ_ALLOC)
1279                         iwl_pcie_rx_allocator_get(trans, rxq);
1280
1281                 if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 && !emergency) {
1282                         struct iwl_rb_allocator *rba = &trans_pcie->rba;
1283
1284                         /* Add the remaining empty RBDs for allocator use */
1285                         spin_lock(&rba->lock);
1286                         list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty);
1287                         spin_unlock(&rba->lock);
1288                 } else if (emergency) {
1289                         count++;
1290                         if (count == 8) {
1291                                 count = 0;
1292                                 if (rxq->used_count < rxq->queue_size / 3)
1293                                         emergency = false;
1294
1295                                 rxq->read = i;
1296                                 spin_unlock(&rxq->lock);
1297                                 iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
1298                                 iwl_pcie_rxq_restock(trans, rxq);
1299                                 goto restart;
1300                         }
1301                 }
1302         }
1303 out:
1304         /* Backtrack one entry */
1305         rxq->read = i;
1306         spin_unlock(&rxq->lock);
1307
1308         /*
1309          * handle a case where in emergency there are some unallocated RBDs.
1310          * those RBDs are in the used list, but are not tracked by the queue's
1311          * used_count which counts allocator owned RBDs.
1312          * unallocated emergency RBDs must be allocated on exit, otherwise
1313          * when called again the function may not be in emergency mode and
1314          * they will be handed to the allocator with no tracking in the RBD
1315          * allocator counters, which will lead to them never being claimed back
1316          * by the queue.
1317          * by allocating them here, they are now in the queue free list, and
1318          * will be restocked by the next call of iwl_pcie_rxq_restock.
1319          */
1320         if (unlikely(emergency && count))
1321                 iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
1322
1323         if (rxq->napi.poll)
1324                 napi_gro_flush(&rxq->napi, false);
1325
1326         iwl_pcie_rxq_restock(trans, rxq);
1327 }
1328
1329 static struct iwl_trans_pcie *iwl_pcie_get_trans_pcie(struct msix_entry *entry)
1330 {
1331         u8 queue = entry->entry;
1332         struct msix_entry *entries = entry - queue;
1333
1334         return container_of(entries, struct iwl_trans_pcie, msix_entries[0]);
1335 }
1336
1337 static inline void iwl_pcie_clear_irq(struct iwl_trans *trans,
1338                                       struct msix_entry *entry)
1339 {
1340         /*
1341          * Before sending the interrupt the HW disables it to prevent
1342          * a nested interrupt. This is done by writing 1 to the corresponding
1343          * bit in the mask register. After handling the interrupt, it should be
1344          * re-enabled by clearing this bit. This register is defined as
1345          * write 1 clear (W1C) register, meaning that it's being clear
1346          * by writing 1 to the bit.
1347          */
1348         iwl_write32(trans, CSR_MSIX_AUTOMASK_ST_AD, BIT(entry->entry));
1349 }
1350
1351 /*
1352  * iwl_pcie_rx_msix_handle - Main entry function for receiving responses from fw
1353  * This interrupt handler should be used with RSS queue only.
1354  */
1355 irqreturn_t iwl_pcie_irq_rx_msix_handler(int irq, void *dev_id)
1356 {
1357         struct msix_entry *entry = dev_id;
1358         struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
1359         struct iwl_trans *trans = trans_pcie->trans;
1360
1361         if (WARN_ON(entry->entry >= trans->num_rx_queues))
1362                 return IRQ_NONE;
1363
1364         lock_map_acquire(&trans->sync_cmd_lockdep_map);
1365
1366         local_bh_disable();
1367         iwl_pcie_rx_handle(trans, entry->entry);
1368         local_bh_enable();
1369
1370         iwl_pcie_clear_irq(trans, entry);
1371
1372         lock_map_release(&trans->sync_cmd_lockdep_map);
1373
1374         return IRQ_HANDLED;
1375 }
1376
1377 /*
1378  * iwl_pcie_irq_handle_error - called for HW or SW error interrupt from card
1379  */
1380 static void iwl_pcie_irq_handle_error(struct iwl_trans *trans)
1381 {
1382         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1383         int i;
1384
1385         /* W/A for WiFi/WiMAX coex and WiMAX own the RF */
1386         if (trans->cfg->internal_wimax_coex &&
1387             !trans->cfg->apmg_not_supported &&
1388             (!(iwl_read_prph(trans, APMG_CLK_CTRL_REG) &
1389                              APMS_CLK_VAL_MRB_FUNC_MODE) ||
1390              (iwl_read_prph(trans, APMG_PS_CTRL_REG) &
1391                             APMG_PS_CTRL_VAL_RESET_REQ))) {
1392                 clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1393                 iwl_op_mode_wimax_active(trans->op_mode);
1394                 wake_up(&trans_pcie->wait_command_queue);
1395                 return;
1396         }
1397
1398         iwl_pcie_dump_csr(trans);
1399         iwl_dump_fh(trans, NULL);
1400
1401         local_bh_disable();
1402         /* The STATUS_FW_ERROR bit is set in this function. This must happen
1403          * before we wake up the command caller, to ensure a proper cleanup. */
1404         iwl_trans_fw_error(trans);
1405         local_bh_enable();
1406
1407         for (i = 0; i < trans->cfg->base_params->num_of_queues; i++)
1408                 del_timer(&trans_pcie->txq[i].stuck_timer);
1409
1410         clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1411         wake_up(&trans_pcie->wait_command_queue);
1412 }
1413
1414 static u32 iwl_pcie_int_cause_non_ict(struct iwl_trans *trans)
1415 {
1416         u32 inta;
1417
1418         lockdep_assert_held(&IWL_TRANS_GET_PCIE_TRANS(trans)->irq_lock);
1419
1420         trace_iwlwifi_dev_irq(trans->dev);
1421
1422         /* Discover which interrupts are active/pending */
1423         inta = iwl_read32(trans, CSR_INT);
1424
1425         /* the thread will service interrupts and re-enable them */
1426         return inta;
1427 }
1428
1429 /* a device (PCI-E) page is 4096 bytes long */
1430 #define ICT_SHIFT       12
1431 #define ICT_SIZE        (1 << ICT_SHIFT)
1432 #define ICT_COUNT       (ICT_SIZE / sizeof(u32))
1433
1434 /* interrupt handler using ict table, with this interrupt driver will
1435  * stop using INTA register to get device's interrupt, reading this register
1436  * is expensive, device will write interrupts in ICT dram table, increment
1437  * index then will fire interrupt to driver, driver will OR all ICT table
1438  * entries from current index up to table entry with 0 value. the result is
1439  * the interrupt we need to service, driver will set the entries back to 0 and
1440  * set index.
1441  */
1442 static u32 iwl_pcie_int_cause_ict(struct iwl_trans *trans)
1443 {
1444         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1445         u32 inta;
1446         u32 val = 0;
1447         u32 read;
1448
1449         trace_iwlwifi_dev_irq(trans->dev);
1450
1451         /* Ignore interrupt if there's nothing in NIC to service.
1452          * This may be due to IRQ shared with another device,
1453          * or due to sporadic interrupts thrown from our NIC. */
1454         read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1455         trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, read);
1456         if (!read)
1457                 return 0;
1458
1459         /*
1460          * Collect all entries up to the first 0, starting from ict_index;
1461          * note we already read at ict_index.
1462          */
1463         do {
1464                 val |= read;
1465                 IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n",
1466                                 trans_pcie->ict_index, read);
1467                 trans_pcie->ict_tbl[trans_pcie->ict_index] = 0;
1468                 trans_pcie->ict_index =
1469                         ((trans_pcie->ict_index + 1) & (ICT_COUNT - 1));
1470
1471                 read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1472                 trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index,
1473                                            read);
1474         } while (read);
1475
1476         /* We should not get this value, just ignore it. */
1477         if (val == 0xffffffff)
1478                 val = 0;
1479
1480         /*
1481          * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit
1482          * (bit 15 before shifting it to 31) to clear when using interrupt
1483          * coalescing. fortunately, bits 18 and 19 stay set when this happens
1484          * so we use them to decide on the real state of the Rx bit.
1485          * In order words, bit 15 is set if bit 18 or bit 19 are set.
1486          */
1487         if (val & 0xC0000)
1488                 val |= 0x8000;
1489
1490         inta = (0xff & val) | ((0xff00 & val) << 16);
1491         return inta;
1492 }
1493
1494 irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id)
1495 {
1496         struct iwl_trans *trans = dev_id;
1497         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1498         struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1499         u32 inta = 0;
1500         u32 handled = 0;
1501
1502         lock_map_acquire(&trans->sync_cmd_lockdep_map);
1503
1504         spin_lock(&trans_pcie->irq_lock);
1505
1506         /* dram interrupt table not set yet,
1507          * use legacy interrupt.
1508          */
1509         if (likely(trans_pcie->use_ict))
1510                 inta = iwl_pcie_int_cause_ict(trans);
1511         else
1512                 inta = iwl_pcie_int_cause_non_ict(trans);
1513
1514         if (iwl_have_debug_level(IWL_DL_ISR)) {
1515                 IWL_DEBUG_ISR(trans,
1516                               "ISR inta 0x%08x, enabled 0x%08x(sw), enabled(hw) 0x%08x, fh 0x%08x\n",
1517                               inta, trans_pcie->inta_mask,
1518                               iwl_read32(trans, CSR_INT_MASK),
1519                               iwl_read32(trans, CSR_FH_INT_STATUS));
1520                 if (inta & (~trans_pcie->inta_mask))
1521                         IWL_DEBUG_ISR(trans,
1522                                       "We got a masked interrupt (0x%08x)\n",
1523                                       inta & (~trans_pcie->inta_mask));
1524         }
1525
1526         inta &= trans_pcie->inta_mask;
1527
1528         /*
1529          * Ignore interrupt if there's nothing in NIC to service.
1530          * This may be due to IRQ shared with another device,
1531          * or due to sporadic interrupts thrown from our NIC.
1532          */
1533         if (unlikely(!inta)) {
1534                 IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1535                 /*
1536                  * Re-enable interrupts here since we don't
1537                  * have anything to service
1538                  */
1539                 if (test_bit(STATUS_INT_ENABLED, &trans->status))
1540                         _iwl_enable_interrupts(trans);
1541                 spin_unlock(&trans_pcie->irq_lock);
1542                 lock_map_release(&trans->sync_cmd_lockdep_map);
1543                 return IRQ_NONE;
1544         }
1545
1546         if (unlikely(inta == 0xFFFFFFFF || (inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
1547                 /*
1548                  * Hardware disappeared. It might have
1549                  * already raised an interrupt.
1550                  */
1551                 IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta);
1552                 spin_unlock(&trans_pcie->irq_lock);
1553                 goto out;
1554         }
1555
1556         /* Ack/clear/reset pending uCode interrupts.
1557          * Note:  Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS,
1558          */
1559         /* There is a hardware bug in the interrupt mask function that some
1560          * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if
1561          * they are disabled in the CSR_INT_MASK register. Furthermore the
1562          * ICT interrupt handling mechanism has another bug that might cause
1563          * these unmasked interrupts fail to be detected. We workaround the
1564          * hardware bugs here by ACKing all the possible interrupts so that
1565          * interrupt coalescing can still be achieved.
1566          */
1567         iwl_write32(trans, CSR_INT, inta | ~trans_pcie->inta_mask);
1568
1569         if (iwl_have_debug_level(IWL_DL_ISR))
1570                 IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n",
1571                               inta, iwl_read32(trans, CSR_INT_MASK));
1572
1573         spin_unlock(&trans_pcie->irq_lock);
1574
1575         /* Now service all interrupt bits discovered above. */
1576         if (inta & CSR_INT_BIT_HW_ERR) {
1577                 IWL_ERR(trans, "Hardware error detected.  Restarting.\n");
1578
1579                 /* Tell the device to stop sending interrupts */
1580                 iwl_disable_interrupts(trans);
1581
1582                 isr_stats->hw++;
1583                 iwl_pcie_irq_handle_error(trans);
1584
1585                 handled |= CSR_INT_BIT_HW_ERR;
1586
1587                 goto out;
1588         }
1589
1590         if (iwl_have_debug_level(IWL_DL_ISR)) {
1591                 /* NIC fires this, but we don't use it, redundant with WAKEUP */
1592                 if (inta & CSR_INT_BIT_SCD) {
1593                         IWL_DEBUG_ISR(trans,
1594                                       "Scheduler finished to transmit the frame/frames.\n");
1595                         isr_stats->sch++;
1596                 }
1597
1598                 /* Alive notification via Rx interrupt will do the real work */
1599                 if (inta & CSR_INT_BIT_ALIVE) {
1600                         IWL_DEBUG_ISR(trans, "Alive interrupt\n");
1601                         isr_stats->alive++;
1602                 }
1603         }
1604
1605         /* Safely ignore these bits for debug checks below */
1606         inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE);
1607
1608         /* HW RF KILL switch toggled */
1609         if (inta & CSR_INT_BIT_RF_KILL) {
1610                 bool hw_rfkill;
1611
1612                 hw_rfkill = iwl_is_rfkill_set(trans);
1613                 IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
1614                          hw_rfkill ? "disable radio" : "enable radio");
1615
1616                 isr_stats->rfkill++;
1617
1618                 mutex_lock(&trans_pcie->mutex);
1619                 iwl_trans_pcie_rf_kill(trans, hw_rfkill);
1620                 mutex_unlock(&trans_pcie->mutex);
1621                 if (hw_rfkill) {
1622                         set_bit(STATUS_RFKILL, &trans->status);
1623                         if (test_and_clear_bit(STATUS_SYNC_HCMD_ACTIVE,
1624                                                &trans->status))
1625                                 IWL_DEBUG_RF_KILL(trans,
1626                                                   "Rfkill while SYNC HCMD in flight\n");
1627                         wake_up(&trans_pcie->wait_command_queue);
1628                 } else {
1629                         clear_bit(STATUS_RFKILL, &trans->status);
1630                 }
1631
1632                 handled |= CSR_INT_BIT_RF_KILL;
1633         }
1634
1635         /* Chip got too hot and stopped itself */
1636         if (inta & CSR_INT_BIT_CT_KILL) {
1637                 IWL_ERR(trans, "Microcode CT kill error detected.\n");
1638                 isr_stats->ctkill++;
1639                 handled |= CSR_INT_BIT_CT_KILL;
1640         }
1641
1642         /* Error detected by uCode */
1643         if (inta & CSR_INT_BIT_SW_ERR) {
1644                 IWL_ERR(trans, "Microcode SW error detected. "
1645                         " Restarting 0x%X.\n", inta);
1646                 isr_stats->sw++;
1647                 iwl_pcie_irq_handle_error(trans);
1648                 handled |= CSR_INT_BIT_SW_ERR;
1649         }
1650
1651         /* uCode wakes up after power-down sleep */
1652         if (inta & CSR_INT_BIT_WAKEUP) {
1653                 IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
1654                 iwl_pcie_rxq_check_wrptr(trans);
1655                 iwl_pcie_txq_check_wrptrs(trans);
1656
1657                 isr_stats->wakeup++;
1658
1659                 handled |= CSR_INT_BIT_WAKEUP;
1660         }
1661
1662         /* All uCode command responses, including Tx command responses,
1663          * Rx "responses" (frame-received notification), and other
1664          * notifications from uCode come through here*/
1665         if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX |
1666                     CSR_INT_BIT_RX_PERIODIC)) {
1667                 IWL_DEBUG_ISR(trans, "Rx interrupt\n");
1668                 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) {
1669                         handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX);
1670                         iwl_write32(trans, CSR_FH_INT_STATUS,
1671                                         CSR_FH_INT_RX_MASK);
1672                 }
1673                 if (inta & CSR_INT_BIT_RX_PERIODIC) {
1674                         handled |= CSR_INT_BIT_RX_PERIODIC;
1675                         iwl_write32(trans,
1676                                 CSR_INT, CSR_INT_BIT_RX_PERIODIC);
1677                 }
1678                 /* Sending RX interrupt require many steps to be done in the
1679                  * the device:
1680                  * 1- write interrupt to current index in ICT table.
1681                  * 2- dma RX frame.
1682                  * 3- update RX shared data to indicate last write index.
1683                  * 4- send interrupt.
1684                  * This could lead to RX race, driver could receive RX interrupt
1685                  * but the shared data changes does not reflect this;
1686                  * periodic interrupt will detect any dangling Rx activity.
1687                  */
1688
1689                 /* Disable periodic interrupt; we use it as just a one-shot. */
1690                 iwl_write8(trans, CSR_INT_PERIODIC_REG,
1691                             CSR_INT_PERIODIC_DIS);
1692
1693                 /*
1694                  * Enable periodic interrupt in 8 msec only if we received
1695                  * real RX interrupt (instead of just periodic int), to catch
1696                  * any dangling Rx interrupt.  If it was just the periodic
1697                  * interrupt, there was no dangling Rx activity, and no need
1698                  * to extend the periodic interrupt; one-shot is enough.
1699                  */
1700                 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX))
1701                         iwl_write8(trans, CSR_INT_PERIODIC_REG,
1702                                    CSR_INT_PERIODIC_ENA);
1703
1704                 isr_stats->rx++;
1705
1706                 local_bh_disable();
1707                 iwl_pcie_rx_handle(trans, 0);
1708                 local_bh_enable();
1709         }
1710
1711         /* This "Tx" DMA channel is used only for loading uCode */
1712         if (inta & CSR_INT_BIT_FH_TX) {
1713                 iwl_write32(trans, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
1714                 IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
1715                 isr_stats->tx++;
1716                 handled |= CSR_INT_BIT_FH_TX;
1717                 /* Wake up uCode load routine, now that load is complete */
1718                 trans_pcie->ucode_write_complete = true;
1719                 wake_up(&trans_pcie->ucode_write_waitq);
1720         }
1721
1722         if (inta & ~handled) {
1723                 IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
1724                 isr_stats->unhandled++;
1725         }
1726
1727         if (inta & ~(trans_pcie->inta_mask)) {
1728                 IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n",
1729                          inta & ~trans_pcie->inta_mask);
1730         }
1731
1732         spin_lock(&trans_pcie->irq_lock);
1733         /* only Re-enable all interrupt if disabled by irq */
1734         if (test_bit(STATUS_INT_ENABLED, &trans->status))
1735                 _iwl_enable_interrupts(trans);
1736         /* we are loading the firmware, enable FH_TX interrupt only */
1737         else if (handled & CSR_INT_BIT_FH_TX)
1738                 iwl_enable_fw_load_int(trans);
1739         /* Re-enable RF_KILL if it occurred */
1740         else if (handled & CSR_INT_BIT_RF_KILL)
1741                 iwl_enable_rfkill_int(trans);
1742         spin_unlock(&trans_pcie->irq_lock);
1743
1744 out:
1745         lock_map_release(&trans->sync_cmd_lockdep_map);
1746         return IRQ_HANDLED;
1747 }
1748
1749 /******************************************************************************
1750  *
1751  * ICT functions
1752  *
1753  ******************************************************************************/
1754
1755 /* Free dram table */
1756 void iwl_pcie_free_ict(struct iwl_trans *trans)
1757 {
1758         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1759
1760         if (trans_pcie->ict_tbl) {
1761                 dma_free_coherent(trans->dev, ICT_SIZE,
1762                                   trans_pcie->ict_tbl,
1763                                   trans_pcie->ict_tbl_dma);
1764                 trans_pcie->ict_tbl = NULL;
1765                 trans_pcie->ict_tbl_dma = 0;
1766         }
1767 }
1768
1769 /*
1770  * allocate dram shared table, it is an aligned memory
1771  * block of ICT_SIZE.
1772  * also reset all data related to ICT table interrupt.
1773  */
1774 int iwl_pcie_alloc_ict(struct iwl_trans *trans)
1775 {
1776         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1777
1778         trans_pcie->ict_tbl =
1779                 dma_zalloc_coherent(trans->dev, ICT_SIZE,
1780                                    &trans_pcie->ict_tbl_dma,
1781                                    GFP_KERNEL);
1782         if (!trans_pcie->ict_tbl)
1783                 return -ENOMEM;
1784
1785         /* just an API sanity check ... it is guaranteed to be aligned */
1786         if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) {
1787                 iwl_pcie_free_ict(trans);
1788                 return -EINVAL;
1789         }
1790
1791         return 0;
1792 }
1793
1794 /* Device is going up inform it about using ICT interrupt table,
1795  * also we need to tell the driver to start using ICT interrupt.
1796  */
1797 void iwl_pcie_reset_ict(struct iwl_trans *trans)
1798 {
1799         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1800         u32 val;
1801
1802         if (!trans_pcie->ict_tbl)
1803                 return;
1804
1805         spin_lock(&trans_pcie->irq_lock);
1806         _iwl_disable_interrupts(trans);
1807
1808         memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
1809
1810         val = trans_pcie->ict_tbl_dma >> ICT_SHIFT;
1811
1812         val |= CSR_DRAM_INT_TBL_ENABLE |
1813                CSR_DRAM_INIT_TBL_WRAP_CHECK |
1814                CSR_DRAM_INIT_TBL_WRITE_POINTER;
1815
1816         IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val);
1817
1818         iwl_write32(trans, CSR_DRAM_INT_TBL_REG, val);
1819         trans_pcie->use_ict = true;
1820         trans_pcie->ict_index = 0;
1821         iwl_write32(trans, CSR_INT, trans_pcie->inta_mask);
1822         _iwl_enable_interrupts(trans);
1823         spin_unlock(&trans_pcie->irq_lock);
1824 }
1825
1826 /* Device is going down disable ict interrupt usage */
1827 void iwl_pcie_disable_ict(struct iwl_trans *trans)
1828 {
1829         struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1830
1831         spin_lock(&trans_pcie->irq_lock);
1832         trans_pcie->use_ict = false;
1833         spin_unlock(&trans_pcie->irq_lock);
1834 }
1835
1836 irqreturn_t iwl_pcie_isr(int irq, void *data)
1837 {
1838         struct iwl_trans *trans = data;
1839
1840         if (!trans)
1841                 return IRQ_NONE;
1842
1843         /* Disable (but don't clear!) interrupts here to avoid
1844          * back-to-back ISRs and sporadic interrupts from our NIC.
1845          * If we have something to service, the tasklet will re-enable ints.
1846          * If we *don't* have something, we'll re-enable before leaving here.
1847          */
1848         iwl_write32(trans, CSR_INT_MASK, 0x00000000);
1849
1850         return IRQ_WAKE_THREAD;
1851 }
1852
1853 irqreturn_t iwl_pcie_msix_isr(int irq, void *data)
1854 {
1855         return IRQ_WAKE_THREAD;
1856 }
1857
1858 irqreturn_t iwl_pcie_irq_msix_handler(int irq, void *dev_id)
1859 {
1860         struct msix_entry *entry = dev_id;
1861         struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
1862         struct iwl_trans *trans = trans_pcie->trans;
1863         struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1864         u32 inta_fh, inta_hw;
1865
1866         lock_map_acquire(&trans->sync_cmd_lockdep_map);
1867
1868         spin_lock(&trans_pcie->irq_lock);
1869         inta_fh = iwl_read32(trans, CSR_MSIX_FH_INT_CAUSES_AD);
1870         inta_hw = iwl_read32(trans, CSR_MSIX_HW_INT_CAUSES_AD);
1871         /*
1872          * Clear causes registers to avoid being handling the same cause.
1873          */
1874         iwl_write32(trans, CSR_MSIX_FH_INT_CAUSES_AD, inta_fh);
1875         iwl_write32(trans, CSR_MSIX_HW_INT_CAUSES_AD, inta_hw);
1876         spin_unlock(&trans_pcie->irq_lock);
1877
1878         if (unlikely(!(inta_fh | inta_hw))) {
1879                 IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1880                 lock_map_release(&trans->sync_cmd_lockdep_map);
1881                 return IRQ_NONE;
1882         }
1883
1884         if (iwl_have_debug_level(IWL_DL_ISR))
1885                 IWL_DEBUG_ISR(trans, "ISR inta_fh 0x%08x, enabled 0x%08x\n",
1886                               inta_fh,
1887                               iwl_read32(trans, CSR_MSIX_FH_INT_MASK_AD));
1888
1889         if ((trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_NON_RX) &&
1890             inta_fh & MSIX_FH_INT_CAUSES_Q0) {
1891                 local_bh_disable();
1892                 iwl_pcie_rx_handle(trans, 0);
1893                 local_bh_enable();
1894         }
1895
1896         if ((trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS) &&
1897             inta_fh & MSIX_FH_INT_CAUSES_Q1) {
1898                 local_bh_disable();
1899                 iwl_pcie_rx_handle(trans, 1);
1900                 local_bh_enable();
1901         }
1902
1903         /* This "Tx" DMA channel is used only for loading uCode */
1904         if (inta_fh & MSIX_FH_INT_CAUSES_D2S_CH0_NUM) {
1905                 IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
1906                 isr_stats->tx++;
1907                 /*
1908                  * Wake up uCode load routine,
1909                  * now that load is complete
1910                  */
1911                 trans_pcie->ucode_write_complete = true;
1912                 wake_up(&trans_pcie->ucode_write_waitq);
1913         }
1914
1915         /* Error detected by uCode */
1916         if ((inta_fh & MSIX_FH_INT_CAUSES_FH_ERR) ||
1917             (inta_hw & MSIX_HW_INT_CAUSES_REG_SW_ERR)) {
1918                 IWL_ERR(trans,
1919                         "Microcode SW error detected. Restarting 0x%X.\n",
1920                         inta_fh);
1921                 isr_stats->sw++;
1922                 iwl_pcie_irq_handle_error(trans);
1923         }
1924
1925         /* After checking FH register check HW register */
1926         if (iwl_have_debug_level(IWL_DL_ISR))
1927                 IWL_DEBUG_ISR(trans,
1928                               "ISR inta_hw 0x%08x, enabled 0x%08x\n",
1929                               inta_hw,
1930                               iwl_read32(trans, CSR_MSIX_HW_INT_MASK_AD));
1931
1932         /* Alive notification via Rx interrupt will do the real work */
1933         if (inta_hw & MSIX_HW_INT_CAUSES_REG_ALIVE) {
1934                 IWL_DEBUG_ISR(trans, "Alive interrupt\n");
1935                 isr_stats->alive++;
1936         }
1937
1938         /* uCode wakes up after power-down sleep */
1939         if (inta_hw & MSIX_HW_INT_CAUSES_REG_WAKEUP) {
1940                 IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
1941                 iwl_pcie_rxq_check_wrptr(trans);
1942                 iwl_pcie_txq_check_wrptrs(trans);
1943
1944                 isr_stats->wakeup++;
1945         }
1946
1947         /* Chip got too hot and stopped itself */
1948         if (inta_hw & MSIX_HW_INT_CAUSES_REG_CT_KILL) {
1949                 IWL_ERR(trans, "Microcode CT kill error detected.\n");
1950                 isr_stats->ctkill++;
1951         }
1952
1953         /* HW RF KILL switch toggled */
1954         if (inta_hw & MSIX_HW_INT_CAUSES_REG_RF_KILL) {
1955                 bool hw_rfkill;
1956
1957                 hw_rfkill = iwl_is_rfkill_set(trans);
1958                 IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
1959                          hw_rfkill ? "disable radio" : "enable radio");
1960
1961                 isr_stats->rfkill++;
1962
1963                 mutex_lock(&trans_pcie->mutex);
1964                 iwl_trans_pcie_rf_kill(trans, hw_rfkill);
1965                 mutex_unlock(&trans_pcie->mutex);
1966                 if (hw_rfkill) {
1967                         set_bit(STATUS_RFKILL, &trans->status);
1968                         if (test_and_clear_bit(STATUS_SYNC_HCMD_ACTIVE,
1969                                                &trans->status))
1970                                 IWL_DEBUG_RF_KILL(trans,
1971                                                   "Rfkill while SYNC HCMD in flight\n");
1972                         wake_up(&trans_pcie->wait_command_queue);
1973                 } else {
1974                         clear_bit(STATUS_RFKILL, &trans->status);
1975                 }
1976         }
1977
1978         if (inta_hw & MSIX_HW_INT_CAUSES_REG_HW_ERR) {
1979                 IWL_ERR(trans,
1980                         "Hardware error detected. Restarting.\n");
1981
1982                 isr_stats->hw++;
1983                 iwl_pcie_irq_handle_error(trans);
1984         }
1985
1986         iwl_pcie_clear_irq(trans, entry);
1987
1988         lock_map_release(&trans->sync_cmd_lockdep_map);
1989
1990         return IRQ_HANDLED;
1991 }