1 /******************************************************************************
3 * Copyright(c) 2003 - 2014 Intel Corporation. All rights reserved.
4 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
6 * Portions of this file are derived from the ipw3945 project, as well
7 * as portions of the ieee80211 subsystem header files.
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
13 * This program is distributed in the hope that it will be useful, but WITHOUT
14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
18 * You should have received a copy of the GNU General Public License along with
19 * this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
22 * The full GNU General Public License is included in this distribution in the
23 * file called LICENSE.
25 * Contact Information:
26 * Intel Linux Wireless <ilw@linux.intel.com>
27 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
29 *****************************************************************************/
30 #include <linux/sched.h>
31 #include <linux/wait.h>
32 #include <linux/gfp.h>
37 #include "iwl-op-mode.h"
39 /******************************************************************************
43 ******************************************************************************/
46 * Rx theory of operation
48 * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
49 * each of which point to Receive Buffers to be filled by the NIC. These get
50 * used not only for Rx frames, but for any command response or notification
51 * from the NIC. The driver and NIC manage the Rx buffers by means
52 * of indexes into the circular buffer.
55 * The host/firmware share two index registers for managing the Rx buffers.
57 * The READ index maps to the first position that the firmware may be writing
58 * to -- the driver can read up to (but not including) this position and get
60 * The READ index is managed by the firmware once the card is enabled.
62 * The WRITE index maps to the last position the driver has read from -- the
63 * position preceding WRITE is the last slot the firmware can place a packet.
65 * The queue is empty (no good data) if WRITE = READ - 1, and is full if
68 * During initialization, the host sets up the READ queue position to the first
69 * INDEX position, and WRITE to the last (READ - 1 wrapped)
71 * When the firmware places a packet in a buffer, it will advance the READ index
72 * and fire the RX interrupt. The driver can then query the READ index and
73 * process as many packets as possible, moving the WRITE index forward as it
74 * resets the Rx queue buffers with new memory.
76 * The management in the driver is as follows:
77 * + A list of pre-allocated RBDs is stored in iwl->rxq->rx_free.
78 * When the interrupt handler is called, the request is processed.
79 * The page is either stolen - transferred to the upper layer
80 * or reused - added immediately to the iwl->rxq->rx_free list.
81 * + When the page is stolen - the driver updates the matching queue's used
82 * count, detaches the RBD and transfers it to the queue used list.
83 * When there are two used RBDs - they are transferred to the allocator empty
84 * list. Work is then scheduled for the allocator to start allocating
86 * When there are another 6 used RBDs - they are transferred to the allocator
87 * empty list and the driver tries to claim the pre-allocated buffers and
88 * add them to iwl->rxq->rx_free. If it fails - it continues to claim them
90 * When there are 8+ buffers in the free list - either from allocation or from
91 * 8 reused unstolen pages - restock is called to update the FW and indexes.
92 * + In order to make sure the allocator always has RBDs to use for allocation
93 * the allocator has initial pool in the size of num_queues*(8-2) - the
94 * maximum missing RBDs per allocation request (request posted with 2
95 * empty RBDs, there is no guarantee when the other 6 RBDs are supplied).
96 * The queues supplies the recycle of the rest of the RBDs.
97 * + A received packet is processed and handed to the kernel network stack,
98 * detached from the iwl->rxq. The driver 'processed' index is updated.
99 * + If there are no allocated buffers in iwl->rxq->rx_free,
100 * the READ INDEX is not incremented and iwl->status(RX_STALLED) is set.
101 * If there were enough free buffers and RX_STALLED is set it is cleared.
106 * iwl_rxq_alloc() Allocates rx_free
107 * iwl_pcie_rx_replenish() Replenishes rx_free list from rx_used, and calls
108 * iwl_pcie_rxq_restock.
109 * Used only during initialization.
110 * iwl_pcie_rxq_restock() Moves available buffers from rx_free into Rx
111 * queue, updates firmware pointers, and updates
113 * iwl_pcie_rx_allocator() Background work for allocating pages.
115 * -- enable interrupts --
116 * ISR - iwl_rx() Detach iwl_rx_mem_buffers from pool up to the
117 * READ INDEX, detaching the SKB from the pool.
118 * Moves the packet buffer from queue to rx_used.
119 * Posts and claims requests to the allocator.
120 * Calls iwl_pcie_rxq_restock to refill any empty
126 * rxq.pool -> rxq.rx_used -> rxq.rx_free -> rxq.queue
128 * Regular Receive interrupt:
130 * rxq.queue -> rxq.rx_used -> allocator.rbd_empty ->
131 * allocator.rbd_allocated -> rxq.rx_free -> rxq.queue
133 * rxq.queue -> rxq.rx_free -> rxq.queue
139 * iwl_rxq_space - Return number of free slots available in queue.
141 static int iwl_rxq_space(const struct iwl_rxq *rxq)
143 /* Make sure RX_QUEUE_SIZE is a power of 2 */
144 BUILD_BUG_ON(RX_QUEUE_SIZE & (RX_QUEUE_SIZE - 1));
147 * There can be up to (RX_QUEUE_SIZE - 1) free slots, to avoid ambiguity
148 * between empty and completely full queues.
149 * The following is equivalent to modulo by RX_QUEUE_SIZE and is well
150 * defined for negative dividends.
152 return (rxq->read - rxq->write - 1) & (RX_QUEUE_SIZE - 1);
156 * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
158 static inline __le32 iwl_pcie_dma_addr2rbd_ptr(dma_addr_t dma_addr)
160 return cpu_to_le32((u32)(dma_addr >> 8));
164 * iwl_pcie_rx_stop - stops the Rx DMA
166 int iwl_pcie_rx_stop(struct iwl_trans *trans)
168 iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
169 return iwl_poll_direct_bit(trans, FH_MEM_RSSR_RX_STATUS_REG,
170 FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000);
174 * iwl_pcie_rxq_inc_wr_ptr - Update the write pointer for the RX queue
176 static void iwl_pcie_rxq_inc_wr_ptr(struct iwl_trans *trans)
178 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
179 struct iwl_rxq *rxq = &trans_pcie->rxq;
182 lockdep_assert_held(&rxq->lock);
185 * explicitly wake up the NIC if:
186 * 1. shadow registers aren't enabled
187 * 2. there is a chance that the NIC is asleep
189 if (!trans->cfg->base_params->shadow_reg_enable &&
190 test_bit(STATUS_TPOWER_PMI, &trans->status)) {
191 reg = iwl_read32(trans, CSR_UCODE_DRV_GP1);
193 if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
194 IWL_DEBUG_INFO(trans, "Rx queue requesting wakeup, GP1 = 0x%x\n",
196 iwl_set_bit(trans, CSR_GP_CNTRL,
197 CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
198 rxq->need_update = true;
203 rxq->write_actual = round_down(rxq->write, 8);
204 iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, rxq->write_actual);
207 static void iwl_pcie_rxq_check_wrptr(struct iwl_trans *trans)
209 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
210 struct iwl_rxq *rxq = &trans_pcie->rxq;
212 spin_lock(&rxq->lock);
214 if (!rxq->need_update)
217 iwl_pcie_rxq_inc_wr_ptr(trans);
218 rxq->need_update = false;
221 spin_unlock(&rxq->lock);
225 * iwl_pcie_rxq_restock - refill RX queue from pre-allocated pool
227 * If there are slots in the RX queue that need to be restocked,
228 * and we have free pre-allocated buffers, fill the ranks as much
229 * as we can, pulling from rx_free.
231 * This moves the 'write' index forward to catch up with 'processed', and
232 * also updates the memory address in the firmware to reference the new
235 static void iwl_pcie_rxq_restock(struct iwl_trans *trans)
237 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
238 struct iwl_rxq *rxq = &trans_pcie->rxq;
239 struct iwl_rx_mem_buffer *rxb;
242 * If the device isn't enabled - not need to try to add buffers...
243 * This can happen when we stop the device and still have an interrupt
244 * pending. We stop the APM before we sync the interrupts because we
245 * have to (see comment there). On the other hand, since the APM is
246 * stopped, we cannot access the HW (in particular not prph).
247 * So don't try to restock if the APM has been already stopped.
249 if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
252 spin_lock(&rxq->lock);
253 while ((iwl_rxq_space(rxq) > 0) && (rxq->free_count)) {
254 /* The overwritten rxb must be a used one */
255 rxb = rxq->queue[rxq->write];
256 BUG_ON(rxb && rxb->page);
258 /* Get next free Rx buffer, remove from free list */
259 rxb = list_first_entry(&rxq->rx_free, struct iwl_rx_mem_buffer,
261 list_del(&rxb->list);
263 /* Point to Rx buffer via next RBD in circular buffer */
264 rxq->bd[rxq->write] = iwl_pcie_dma_addr2rbd_ptr(rxb->page_dma);
265 rxq->queue[rxq->write] = rxb;
266 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
269 spin_unlock(&rxq->lock);
271 /* If we've added more space for the firmware to place data, tell it.
272 * Increment device's write pointer in multiples of 8. */
273 if (rxq->write_actual != (rxq->write & ~0x7)) {
274 spin_lock(&rxq->lock);
275 iwl_pcie_rxq_inc_wr_ptr(trans);
276 spin_unlock(&rxq->lock);
281 * iwl_pcie_rx_alloc_page - allocates and returns a page.
284 static struct page *iwl_pcie_rx_alloc_page(struct iwl_trans *trans,
287 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
288 struct iwl_rxq *rxq = &trans_pcie->rxq;
290 gfp_t gfp_mask = priority;
292 if (rxq->free_count > RX_LOW_WATERMARK)
293 gfp_mask |= __GFP_NOWARN;
295 if (trans_pcie->rx_page_order > 0)
296 gfp_mask |= __GFP_COMP;
298 /* Alloc a new receive buffer */
299 page = alloc_pages(gfp_mask, trans_pcie->rx_page_order);
302 IWL_DEBUG_INFO(trans, "alloc_pages failed, order: %d\n",
303 trans_pcie->rx_page_order);
304 /* Issue an error if the hardware has consumed more than half
305 * of its free buffer list and we don't have enough
306 * pre-allocated buffers.
308 if (rxq->free_count <= RX_LOW_WATERMARK &&
309 iwl_rxq_space(rxq) > (RX_QUEUE_SIZE / 2) &&
312 "Failed to alloc_pages with GFP_KERNEL. Only %u free buffers remaining.\n",
320 * iwl_pcie_rxq_alloc_rbs - allocate a page for each used RBD
322 * A used RBD is an Rx buffer that has been given to the stack. To use it again
323 * a page must be allocated and the RBD must point to the page. This function
324 * doesn't change the HW pointer but handles the list of pages that is used by
325 * iwl_pcie_rxq_restock. The latter function will update the HW to use the newly
328 static void iwl_pcie_rxq_alloc_rbs(struct iwl_trans *trans, gfp_t priority)
330 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
331 struct iwl_rxq *rxq = &trans_pcie->rxq;
332 struct iwl_rx_mem_buffer *rxb;
336 spin_lock(&rxq->lock);
337 if (list_empty(&rxq->rx_used)) {
338 spin_unlock(&rxq->lock);
341 spin_unlock(&rxq->lock);
343 /* Alloc a new receive buffer */
344 page = iwl_pcie_rx_alloc_page(trans, priority);
348 spin_lock(&rxq->lock);
350 if (list_empty(&rxq->rx_used)) {
351 spin_unlock(&rxq->lock);
352 __free_pages(page, trans_pcie->rx_page_order);
355 rxb = list_first_entry(&rxq->rx_used, struct iwl_rx_mem_buffer,
357 list_del(&rxb->list);
358 spin_unlock(&rxq->lock);
362 /* Get physical address of the RB */
364 dma_map_page(trans->dev, page, 0,
365 PAGE_SIZE << trans_pcie->rx_page_order,
367 if (dma_mapping_error(trans->dev, rxb->page_dma)) {
369 spin_lock(&rxq->lock);
370 list_add(&rxb->list, &rxq->rx_used);
371 spin_unlock(&rxq->lock);
372 __free_pages(page, trans_pcie->rx_page_order);
375 /* dma address must be no more than 36 bits */
376 BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
377 /* and also 256 byte aligned! */
378 BUG_ON(rxb->page_dma & DMA_BIT_MASK(8));
380 spin_lock(&rxq->lock);
382 list_add_tail(&rxb->list, &rxq->rx_free);
385 spin_unlock(&rxq->lock);
389 static void iwl_pcie_rxq_free_rbs(struct iwl_trans *trans)
391 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
392 struct iwl_rxq *rxq = &trans_pcie->rxq;
395 lockdep_assert_held(&rxq->lock);
397 for (i = 0; i < RX_QUEUE_SIZE; i++) {
398 if (!rxq->pool[i].page)
400 dma_unmap_page(trans->dev, rxq->pool[i].page_dma,
401 PAGE_SIZE << trans_pcie->rx_page_order,
403 __free_pages(rxq->pool[i].page, trans_pcie->rx_page_order);
404 rxq->pool[i].page = NULL;
409 * iwl_pcie_rx_replenish - Move all used buffers from rx_used to rx_free
411 * When moving to rx_free an page is allocated for the slot.
413 * Also restock the Rx queue via iwl_pcie_rxq_restock.
414 * This is called only during initialization
416 static void iwl_pcie_rx_replenish(struct iwl_trans *trans)
418 iwl_pcie_rxq_alloc_rbs(trans, GFP_KERNEL);
420 iwl_pcie_rxq_restock(trans);
424 * iwl_pcie_rx_allocator - Allocates pages in the background for RX queues
426 * Allocates for each received request 8 pages
427 * Called as a scheduled work item.
429 static void iwl_pcie_rx_allocator(struct iwl_trans *trans)
431 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
432 struct iwl_rb_allocator *rba = &trans_pcie->rba;
433 struct list_head local_empty;
434 int pending = atomic_xchg(&rba->req_pending, 0);
436 IWL_DEBUG_RX(trans, "Pending allocation requests = %d\n", pending);
438 /* If we were scheduled - there is at least one request */
439 spin_lock(&rba->lock);
440 /* swap out the rba->rbd_empty to a local list */
441 list_replace_init(&rba->rbd_empty, &local_empty);
442 spin_unlock(&rba->lock);
446 struct list_head local_allocated;
448 INIT_LIST_HEAD(&local_allocated);
450 for (i = 0; i < RX_CLAIM_REQ_ALLOC;) {
451 struct iwl_rx_mem_buffer *rxb;
454 /* List should never be empty - each reused RBD is
455 * returned to the list, and initial pool covers any
456 * possible gap between the time the page is allocated
457 * to the time the RBD is added.
459 BUG_ON(list_empty(&local_empty));
460 /* Get the first rxb from the rbd list */
461 rxb = list_first_entry(&local_empty,
462 struct iwl_rx_mem_buffer, list);
465 /* Alloc a new receive buffer */
466 page = iwl_pcie_rx_alloc_page(trans, GFP_KERNEL);
471 /* Get physical address of the RB */
472 rxb->page_dma = dma_map_page(trans->dev, page, 0,
473 PAGE_SIZE << trans_pcie->rx_page_order,
475 if (dma_mapping_error(trans->dev, rxb->page_dma)) {
477 __free_pages(page, trans_pcie->rx_page_order);
480 /* dma address must be no more than 36 bits */
481 BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
482 /* and also 256 byte aligned! */
483 BUG_ON(rxb->page_dma & DMA_BIT_MASK(8));
485 /* move the allocated entry to the out list */
486 list_move(&rxb->list, &local_allocated);
492 pending = atomic_xchg(&rba->req_pending, 0);
494 "Pending allocation requests = %d\n",
498 spin_lock(&rba->lock);
499 /* add the allocated rbds to the allocator allocated list */
500 list_splice_tail(&local_allocated, &rba->rbd_allocated);
501 /* get more empty RBDs for current pending requests */
502 list_splice_tail_init(&rba->rbd_empty, &local_empty);
503 spin_unlock(&rba->lock);
505 atomic_inc(&rba->req_ready);
508 spin_lock(&rba->lock);
509 /* return unused rbds to the allocator empty list */
510 list_splice_tail(&local_empty, &rba->rbd_empty);
511 spin_unlock(&rba->lock);
515 * iwl_pcie_rx_allocator_get - Returns the pre-allocated pages
517 .* Called by queue when the queue posted allocation request and
518 * has freed 8 RBDs in order to restock itself.
520 static int iwl_pcie_rx_allocator_get(struct iwl_trans *trans,
521 struct iwl_rx_mem_buffer
522 *out[RX_CLAIM_REQ_ALLOC])
524 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
525 struct iwl_rb_allocator *rba = &trans_pcie->rba;
529 * atomic_dec_if_positive returns req_ready - 1 for any scenario.
530 * If req_ready is 0 atomic_dec_if_positive will return -1 and this
531 * function will return -ENOMEM, as there are no ready requests.
532 * atomic_dec_if_positive will perofrm the *actual* decrement only if
533 * req_ready > 0, i.e. - there are ready requests and the function
534 * hands one request to the caller.
536 if (atomic_dec_if_positive(&rba->req_ready) < 0)
539 spin_lock(&rba->lock);
540 for (i = 0; i < RX_CLAIM_REQ_ALLOC; i++) {
541 /* Get next free Rx buffer, remove it from free list */
542 out[i] = list_first_entry(&rba->rbd_allocated,
543 struct iwl_rx_mem_buffer, list);
544 list_del(&out[i]->list);
546 spin_unlock(&rba->lock);
551 static void iwl_pcie_rx_allocator_work(struct work_struct *data)
553 struct iwl_rb_allocator *rba_p =
554 container_of(data, struct iwl_rb_allocator, rx_alloc);
555 struct iwl_trans_pcie *trans_pcie =
556 container_of(rba_p, struct iwl_trans_pcie, rba);
558 iwl_pcie_rx_allocator(trans_pcie->trans);
561 static int iwl_pcie_rx_alloc(struct iwl_trans *trans)
563 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
564 struct iwl_rxq *rxq = &trans_pcie->rxq;
565 struct iwl_rb_allocator *rba = &trans_pcie->rba;
566 struct device *dev = trans->dev;
568 memset(&trans_pcie->rxq, 0, sizeof(trans_pcie->rxq));
570 spin_lock_init(&rxq->lock);
571 spin_lock_init(&rba->lock);
573 if (WARN_ON(rxq->bd || rxq->rb_stts))
576 /* Allocate the circular buffer of Read Buffer Descriptors (RBDs) */
577 rxq->bd = dma_zalloc_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE,
578 &rxq->bd_dma, GFP_KERNEL);
582 /*Allocate the driver's pointer to receive buffer status */
583 rxq->rb_stts = dma_zalloc_coherent(dev, sizeof(*rxq->rb_stts),
584 &rxq->rb_stts_dma, GFP_KERNEL);
591 dma_free_coherent(dev, sizeof(__le32) * RX_QUEUE_SIZE,
592 rxq->bd, rxq->bd_dma);
599 static void iwl_pcie_rx_hw_init(struct iwl_trans *trans, struct iwl_rxq *rxq)
601 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
603 const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
605 if (trans_pcie->rx_buf_size_8k)
606 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
608 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
611 iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
612 /* reset and flush pointers */
613 iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_RBDCB_WPTR, 0);
614 iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_FLUSH_RB_REQ, 0);
615 iwl_write_direct32(trans, FH_RSCSR_CHNL0_RDPTR, 0);
617 /* Reset driver's Rx queue write index */
618 iwl_write_direct32(trans, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
620 /* Tell device where to find RBD circular buffer in DRAM */
621 iwl_write_direct32(trans, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
622 (u32)(rxq->bd_dma >> 8));
624 /* Tell device where in DRAM to update its Rx status */
625 iwl_write_direct32(trans, FH_RSCSR_CHNL0_STTS_WPTR_REG,
626 rxq->rb_stts_dma >> 4);
629 * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in
630 * the credit mechanism in 5000 HW RX FIFO
631 * Direct rx interrupts to hosts
632 * Rx buffer size 4 or 8k
636 iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG,
637 FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
638 FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY |
639 FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
641 (RX_RB_TIMEOUT << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS)|
642 (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));
644 /* Set interrupt coalescing timer to default (2048 usecs) */
645 iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
647 /* W/A for interrupt coalescing bug in 7260 and 3160 */
648 if (trans->cfg->host_interrupt_operation_mode)
649 iwl_set_bit(trans, CSR_INT_COALESCING, IWL_HOST_INT_OPER_MODE);
652 static void iwl_pcie_rx_init_rxb_lists(struct iwl_rxq *rxq)
656 lockdep_assert_held(&rxq->lock);
658 INIT_LIST_HEAD(&rxq->rx_free);
659 INIT_LIST_HEAD(&rxq->rx_used);
663 for (i = 0; i < RX_QUEUE_SIZE; i++)
664 list_add(&rxq->pool[i].list, &rxq->rx_used);
667 static void iwl_pcie_rx_init_rba(struct iwl_rb_allocator *rba)
671 lockdep_assert_held(&rba->lock);
673 INIT_LIST_HEAD(&rba->rbd_allocated);
674 INIT_LIST_HEAD(&rba->rbd_empty);
676 for (i = 0; i < RX_POOL_SIZE; i++)
677 list_add(&rba->pool[i].list, &rba->rbd_empty);
680 static void iwl_pcie_rx_free_rba(struct iwl_trans *trans)
682 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
683 struct iwl_rb_allocator *rba = &trans_pcie->rba;
686 lockdep_assert_held(&rba->lock);
688 for (i = 0; i < RX_POOL_SIZE; i++) {
689 if (!rba->pool[i].page)
691 dma_unmap_page(trans->dev, rba->pool[i].page_dma,
692 PAGE_SIZE << trans_pcie->rx_page_order,
694 __free_pages(rba->pool[i].page, trans_pcie->rx_page_order);
695 rba->pool[i].page = NULL;
699 int iwl_pcie_rx_init(struct iwl_trans *trans)
701 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
702 struct iwl_rxq *rxq = &trans_pcie->rxq;
703 struct iwl_rb_allocator *rba = &trans_pcie->rba;
707 err = iwl_pcie_rx_alloc(trans);
712 rba->alloc_wq = alloc_workqueue("rb_allocator",
713 WQ_HIGHPRI | WQ_UNBOUND, 1);
714 INIT_WORK(&rba->rx_alloc, iwl_pcie_rx_allocator_work);
716 spin_lock(&rba->lock);
717 atomic_set(&rba->req_pending, 0);
718 atomic_set(&rba->req_ready, 0);
719 /* free all first - we might be reconfigured for a different size */
720 iwl_pcie_rx_free_rba(trans);
721 iwl_pcie_rx_init_rba(rba);
722 spin_unlock(&rba->lock);
724 spin_lock(&rxq->lock);
726 /* free all first - we might be reconfigured for a different size */
727 iwl_pcie_rxq_free_rbs(trans);
728 iwl_pcie_rx_init_rxb_lists(rxq);
730 for (i = 0; i < RX_QUEUE_SIZE; i++)
731 rxq->queue[i] = NULL;
733 /* Set us so that we have processed and used all buffers, but have
734 * not restocked the Rx queue with fresh buffers */
735 rxq->read = rxq->write = 0;
736 rxq->write_actual = 0;
737 memset(rxq->rb_stts, 0, sizeof(*rxq->rb_stts));
738 spin_unlock(&rxq->lock);
740 iwl_pcie_rx_replenish(trans);
742 iwl_pcie_rx_hw_init(trans, rxq);
744 spin_lock(&rxq->lock);
745 iwl_pcie_rxq_inc_wr_ptr(trans);
746 spin_unlock(&rxq->lock);
751 void iwl_pcie_rx_free(struct iwl_trans *trans)
753 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
754 struct iwl_rxq *rxq = &trans_pcie->rxq;
755 struct iwl_rb_allocator *rba = &trans_pcie->rba;
757 /*if rxq->bd is NULL, it means that nothing has been allocated,
760 IWL_DEBUG_INFO(trans, "Free NULL rx context\n");
764 cancel_work_sync(&rba->rx_alloc);
766 destroy_workqueue(rba->alloc_wq);
767 rba->alloc_wq = NULL;
770 spin_lock(&rba->lock);
771 iwl_pcie_rx_free_rba(trans);
772 spin_unlock(&rba->lock);
774 spin_lock(&rxq->lock);
775 iwl_pcie_rxq_free_rbs(trans);
776 spin_unlock(&rxq->lock);
778 dma_free_coherent(trans->dev, sizeof(__le32) * RX_QUEUE_SIZE,
779 rxq->bd, rxq->bd_dma);
784 dma_free_coherent(trans->dev,
785 sizeof(struct iwl_rb_status),
786 rxq->rb_stts, rxq->rb_stts_dma);
788 IWL_DEBUG_INFO(trans, "Free rxq->rb_stts which is NULL\n");
789 rxq->rb_stts_dma = 0;
794 * iwl_pcie_rx_reuse_rbd - Recycle used RBDs
796 * Called when a RBD can be reused. The RBD is transferred to the allocator.
797 * When there are 2 empty RBDs - a request for allocation is posted
799 static void iwl_pcie_rx_reuse_rbd(struct iwl_trans *trans,
800 struct iwl_rx_mem_buffer *rxb,
801 struct iwl_rxq *rxq, bool emergency)
803 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
804 struct iwl_rb_allocator *rba = &trans_pcie->rba;
806 /* Move the RBD to the used list, will be moved to allocator in batches
807 * before claiming or posting a request*/
808 list_add_tail(&rxb->list, &rxq->rx_used);
810 if (unlikely(emergency))
813 /* Count the allocator owned RBDs */
816 /* If we have RX_POST_REQ_ALLOC new released rx buffers -
817 * issue a request for allocator. Modulo RX_CLAIM_REQ_ALLOC is
818 * used for the case we failed to claim RX_CLAIM_REQ_ALLOC,
819 * after but we still need to post another request.
821 if ((rxq->used_count % RX_CLAIM_REQ_ALLOC) == RX_POST_REQ_ALLOC) {
822 /* Move the 2 RBDs to the allocator ownership.
823 Allocator has another 6 from pool for the request completion*/
824 spin_lock(&rba->lock);
825 list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty);
826 spin_unlock(&rba->lock);
828 atomic_inc(&rba->req_pending);
829 queue_work(rba->alloc_wq, &rba->rx_alloc);
833 static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
834 struct iwl_rx_mem_buffer *rxb,
837 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
838 struct iwl_rxq *rxq = &trans_pcie->rxq;
839 struct iwl_txq *txq = &trans_pcie->txq[trans_pcie->cmd_queue];
840 bool page_stolen = false;
841 int max_len = PAGE_SIZE << trans_pcie->rx_page_order;
847 dma_unmap_page(trans->dev, rxb->page_dma, max_len, DMA_FROM_DEVICE);
849 while (offset + sizeof(u32) + sizeof(struct iwl_cmd_header) < max_len) {
850 struct iwl_rx_packet *pkt;
853 int index, cmd_index, len;
854 struct iwl_rx_cmd_buffer rxcb = {
856 ._rx_page_order = trans_pcie->rx_page_order,
858 ._page_stolen = false,
862 pkt = rxb_addr(&rxcb);
864 if (pkt->len_n_flags == cpu_to_le32(FH_RSCSR_FRAME_INVALID))
868 "cmd at offset %d: %s (0x%.2x, seq 0x%x)\n",
870 get_cmd_string(trans_pcie, pkt->hdr.cmd),
871 pkt->hdr.cmd, le16_to_cpu(pkt->hdr.sequence));
873 len = iwl_rx_packet_len(pkt);
874 len += sizeof(u32); /* account for status word */
875 trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len);
876 trace_iwlwifi_dev_rx_data(trans->dev, trans, pkt, len);
878 /* Reclaim a command buffer only if this packet is a response
879 * to a (driver-originated) command.
880 * If the packet (e.g. Rx frame) originated from uCode,
881 * there is no command buffer to reclaim.
882 * Ucode should set SEQ_RX_FRAME bit if ucode-originated,
883 * but apparently a few don't get set; catch them here. */
884 reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME);
888 for (i = 0; i < trans_pcie->n_no_reclaim_cmds; i++) {
889 if (trans_pcie->no_reclaim_cmds[i] ==
897 sequence = le16_to_cpu(pkt->hdr.sequence);
898 index = SEQ_TO_INDEX(sequence);
899 cmd_index = get_cmd_index(&txq->q, index);
901 iwl_op_mode_rx(trans->op_mode, &trans_pcie->napi, &rxcb);
904 kzfree(txq->entries[cmd_index].free_buf);
905 txq->entries[cmd_index].free_buf = NULL;
909 * After here, we should always check rxcb._page_stolen,
910 * if it is true then one of the handlers took the page.
914 /* Invoke any callbacks, transfer the buffer to caller,
915 * and fire off the (possibly) blocking
916 * iwl_trans_send_cmd()
917 * as we reclaim the driver command queue */
918 if (!rxcb._page_stolen)
919 iwl_pcie_hcmd_complete(trans, &rxcb);
921 IWL_WARN(trans, "Claim null rxb?\n");
924 page_stolen |= rxcb._page_stolen;
925 offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
928 /* page was stolen from us -- free our reference */
930 __free_pages(rxb->page, trans_pcie->rx_page_order);
934 /* Reuse the page if possible. For notification packets and
935 * SKBs that fail to Rx correctly, add them back into the
936 * rx_free list for reuse later. */
937 if (rxb->page != NULL) {
939 dma_map_page(trans->dev, rxb->page, 0,
940 PAGE_SIZE << trans_pcie->rx_page_order,
942 if (dma_mapping_error(trans->dev, rxb->page_dma)) {
944 * free the page(s) as well to not break
945 * the invariant that the items on the used
946 * list have no page(s)
948 __free_pages(rxb->page, trans_pcie->rx_page_order);
950 iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
952 list_add_tail(&rxb->list, &rxq->rx_free);
956 iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
960 * iwl_pcie_rx_handle - Main entry function for receiving responses from fw
962 static void iwl_pcie_rx_handle(struct iwl_trans *trans)
964 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
965 struct iwl_rxq *rxq = &trans_pcie->rxq;
966 u32 r, i, j, count = 0;
967 bool emergency = false;
970 spin_lock(&rxq->lock);
971 /* uCode's read index (stored in shared DRAM) indicates the last Rx
972 * buffer that the driver may process (last buffer filled by ucode). */
973 r = le16_to_cpu(ACCESS_ONCE(rxq->rb_stts->closed_rb_num)) & 0x0FFF;
976 /* Rx interrupt, but nothing sent from uCode */
978 IWL_DEBUG_RX(trans, "HW = SW = %d\n", r);
981 struct iwl_rx_mem_buffer *rxb;
983 if (unlikely(rxq->used_count == RX_QUEUE_SIZE / 2))
987 rxq->queue[i] = NULL;
989 IWL_DEBUG_RX(trans, "rxbuf: HW = %d, SW = %d (%p)\n",
991 iwl_pcie_rx_handle_rb(trans, rxb, emergency);
993 i = (i + 1) & RX_QUEUE_MASK;
995 /* If we have RX_CLAIM_REQ_ALLOC released rx buffers -
996 * try to claim the pre-allocated buffers from the allocator */
997 if (rxq->used_count >= RX_CLAIM_REQ_ALLOC) {
998 struct iwl_rb_allocator *rba = &trans_pcie->rba;
999 struct iwl_rx_mem_buffer *out[RX_CLAIM_REQ_ALLOC];
1001 if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 &&
1003 /* Add the remaining 6 empty RBDs
1006 spin_lock(&rba->lock);
1007 list_splice_tail_init(&rxq->rx_used,
1009 spin_unlock(&rba->lock);
1012 /* If not ready - continue, will try to reclaim later.
1013 * No need to reschedule work - allocator exits only on
1015 if (!iwl_pcie_rx_allocator_get(trans, out)) {
1016 /* If success - then RX_CLAIM_REQ_ALLOC
1017 * buffers were retrieved and should be added
1019 rxq->used_count -= RX_CLAIM_REQ_ALLOC;
1020 for (j = 0; j < RX_CLAIM_REQ_ALLOC; j++) {
1021 list_add_tail(&out[j]->list,
1031 if (rxq->used_count < RX_QUEUE_SIZE / 3)
1033 spin_unlock(&rxq->lock);
1034 iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC);
1035 spin_lock(&rxq->lock);
1038 /* handle restock for three cases, can be all of them at once:
1039 * - we just pulled buffers from the allocator
1040 * - we have 8+ unstolen pages accumulated
1041 * - we are in emergency and allocated buffers
1043 if (rxq->free_count >= RX_CLAIM_REQ_ALLOC) {
1045 spin_unlock(&rxq->lock);
1046 iwl_pcie_rxq_restock(trans);
1051 /* Backtrack one entry */
1053 spin_unlock(&rxq->lock);
1056 * handle a case where in emergency there are some unallocated RBDs.
1057 * those RBDs are in the used list, but are not tracked by the queue's
1058 * used_count which counts allocator owned RBDs.
1059 * unallocated emergency RBDs must be allocated on exit, otherwise
1060 * when called again the function may not be in emergency mode and
1061 * they will be handed to the allocator with no tracking in the RBD
1062 * allocator counters, which will lead to them never being claimed back
1064 * by allocating them here, they are now in the queue free list, and
1065 * will be restocked by the next call of iwl_pcie_rxq_restock.
1067 if (unlikely(emergency && count))
1068 iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC);
1070 if (trans_pcie->napi.poll)
1071 napi_gro_flush(&trans_pcie->napi, false);
1075 * iwl_pcie_irq_handle_error - called for HW or SW error interrupt from card
1077 static void iwl_pcie_irq_handle_error(struct iwl_trans *trans)
1079 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1082 /* W/A for WiFi/WiMAX coex and WiMAX own the RF */
1083 if (trans->cfg->internal_wimax_coex &&
1084 !trans->cfg->apmg_not_supported &&
1085 (!(iwl_read_prph(trans, APMG_CLK_CTRL_REG) &
1086 APMS_CLK_VAL_MRB_FUNC_MODE) ||
1087 (iwl_read_prph(trans, APMG_PS_CTRL_REG) &
1088 APMG_PS_CTRL_VAL_RESET_REQ))) {
1089 clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1090 iwl_op_mode_wimax_active(trans->op_mode);
1091 wake_up(&trans_pcie->wait_command_queue);
1095 iwl_pcie_dump_csr(trans);
1096 iwl_dump_fh(trans, NULL);
1099 /* The STATUS_FW_ERROR bit is set in this function. This must happen
1100 * before we wake up the command caller, to ensure a proper cleanup. */
1101 iwl_trans_fw_error(trans);
1104 for (i = 0; i < trans->cfg->base_params->num_of_queues; i++)
1105 del_timer(&trans_pcie->txq[i].stuck_timer);
1107 clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1108 wake_up(&trans_pcie->wait_command_queue);
1111 static u32 iwl_pcie_int_cause_non_ict(struct iwl_trans *trans)
1115 lockdep_assert_held(&IWL_TRANS_GET_PCIE_TRANS(trans)->irq_lock);
1117 trace_iwlwifi_dev_irq(trans->dev);
1119 /* Discover which interrupts are active/pending */
1120 inta = iwl_read32(trans, CSR_INT);
1122 /* the thread will service interrupts and re-enable them */
1126 /* a device (PCI-E) page is 4096 bytes long */
1127 #define ICT_SHIFT 12
1128 #define ICT_SIZE (1 << ICT_SHIFT)
1129 #define ICT_COUNT (ICT_SIZE / sizeof(u32))
1131 /* interrupt handler using ict table, with this interrupt driver will
1132 * stop using INTA register to get device's interrupt, reading this register
1133 * is expensive, device will write interrupts in ICT dram table, increment
1134 * index then will fire interrupt to driver, driver will OR all ICT table
1135 * entries from current index up to table entry with 0 value. the result is
1136 * the interrupt we need to service, driver will set the entries back to 0 and
1139 static u32 iwl_pcie_int_cause_ict(struct iwl_trans *trans)
1141 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1146 trace_iwlwifi_dev_irq(trans->dev);
1148 /* Ignore interrupt if there's nothing in NIC to service.
1149 * This may be due to IRQ shared with another device,
1150 * or due to sporadic interrupts thrown from our NIC. */
1151 read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1152 trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, read);
1157 * Collect all entries up to the first 0, starting from ict_index;
1158 * note we already read at ict_index.
1162 IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n",
1163 trans_pcie->ict_index, read);
1164 trans_pcie->ict_tbl[trans_pcie->ict_index] = 0;
1165 trans_pcie->ict_index =
1166 ((trans_pcie->ict_index + 1) & (ICT_COUNT - 1));
1168 read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1169 trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index,
1173 /* We should not get this value, just ignore it. */
1174 if (val == 0xffffffff)
1178 * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit
1179 * (bit 15 before shifting it to 31) to clear when using interrupt
1180 * coalescing. fortunately, bits 18 and 19 stay set when this happens
1181 * so we use them to decide on the real state of the Rx bit.
1182 * In order words, bit 15 is set if bit 18 or bit 19 are set.
1187 inta = (0xff & val) | ((0xff00 & val) << 16);
1191 irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id)
1193 struct iwl_trans *trans = dev_id;
1194 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1195 struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1199 lock_map_acquire(&trans->sync_cmd_lockdep_map);
1201 spin_lock(&trans_pcie->irq_lock);
1203 /* dram interrupt table not set yet,
1204 * use legacy interrupt.
1206 if (likely(trans_pcie->use_ict))
1207 inta = iwl_pcie_int_cause_ict(trans);
1209 inta = iwl_pcie_int_cause_non_ict(trans);
1211 if (iwl_have_debug_level(IWL_DL_ISR)) {
1212 IWL_DEBUG_ISR(trans,
1213 "ISR inta 0x%08x, enabled 0x%08x(sw), enabled(hw) 0x%08x, fh 0x%08x\n",
1214 inta, trans_pcie->inta_mask,
1215 iwl_read32(trans, CSR_INT_MASK),
1216 iwl_read32(trans, CSR_FH_INT_STATUS));
1217 if (inta & (~trans_pcie->inta_mask))
1218 IWL_DEBUG_ISR(trans,
1219 "We got a masked interrupt (0x%08x)\n",
1220 inta & (~trans_pcie->inta_mask));
1223 inta &= trans_pcie->inta_mask;
1226 * Ignore interrupt if there's nothing in NIC to service.
1227 * This may be due to IRQ shared with another device,
1228 * or due to sporadic interrupts thrown from our NIC.
1230 if (unlikely(!inta)) {
1231 IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1233 * Re-enable interrupts here since we don't
1234 * have anything to service
1236 if (test_bit(STATUS_INT_ENABLED, &trans->status))
1237 iwl_enable_interrupts(trans);
1238 spin_unlock(&trans_pcie->irq_lock);
1239 lock_map_release(&trans->sync_cmd_lockdep_map);
1243 if (unlikely(inta == 0xFFFFFFFF || (inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
1245 * Hardware disappeared. It might have
1246 * already raised an interrupt.
1248 IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta);
1249 spin_unlock(&trans_pcie->irq_lock);
1253 /* Ack/clear/reset pending uCode interrupts.
1254 * Note: Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS,
1256 /* There is a hardware bug in the interrupt mask function that some
1257 * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if
1258 * they are disabled in the CSR_INT_MASK register. Furthermore the
1259 * ICT interrupt handling mechanism has another bug that might cause
1260 * these unmasked interrupts fail to be detected. We workaround the
1261 * hardware bugs here by ACKing all the possible interrupts so that
1262 * interrupt coalescing can still be achieved.
1264 iwl_write32(trans, CSR_INT, inta | ~trans_pcie->inta_mask);
1266 if (iwl_have_debug_level(IWL_DL_ISR))
1267 IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n",
1268 inta, iwl_read32(trans, CSR_INT_MASK));
1270 spin_unlock(&trans_pcie->irq_lock);
1272 /* Now service all interrupt bits discovered above. */
1273 if (inta & CSR_INT_BIT_HW_ERR) {
1274 IWL_ERR(trans, "Hardware error detected. Restarting.\n");
1276 /* Tell the device to stop sending interrupts */
1277 iwl_disable_interrupts(trans);
1280 iwl_pcie_irq_handle_error(trans);
1282 handled |= CSR_INT_BIT_HW_ERR;
1287 if (iwl_have_debug_level(IWL_DL_ISR)) {
1288 /* NIC fires this, but we don't use it, redundant with WAKEUP */
1289 if (inta & CSR_INT_BIT_SCD) {
1290 IWL_DEBUG_ISR(trans,
1291 "Scheduler finished to transmit the frame/frames.\n");
1295 /* Alive notification via Rx interrupt will do the real work */
1296 if (inta & CSR_INT_BIT_ALIVE) {
1297 IWL_DEBUG_ISR(trans, "Alive interrupt\n");
1302 /* Safely ignore these bits for debug checks below */
1303 inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE);
1305 /* HW RF KILL switch toggled */
1306 if (inta & CSR_INT_BIT_RF_KILL) {
1309 hw_rfkill = iwl_is_rfkill_set(trans);
1310 IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
1311 hw_rfkill ? "disable radio" : "enable radio");
1313 isr_stats->rfkill++;
1315 mutex_lock(&trans_pcie->mutex);
1316 iwl_trans_pcie_rf_kill(trans, hw_rfkill);
1317 mutex_unlock(&trans_pcie->mutex);
1319 set_bit(STATUS_RFKILL, &trans->status);
1320 if (test_and_clear_bit(STATUS_SYNC_HCMD_ACTIVE,
1322 IWL_DEBUG_RF_KILL(trans,
1323 "Rfkill while SYNC HCMD in flight\n");
1324 wake_up(&trans_pcie->wait_command_queue);
1326 clear_bit(STATUS_RFKILL, &trans->status);
1329 handled |= CSR_INT_BIT_RF_KILL;
1332 /* Chip got too hot and stopped itself */
1333 if (inta & CSR_INT_BIT_CT_KILL) {
1334 IWL_ERR(trans, "Microcode CT kill error detected.\n");
1335 isr_stats->ctkill++;
1336 handled |= CSR_INT_BIT_CT_KILL;
1339 /* Error detected by uCode */
1340 if (inta & CSR_INT_BIT_SW_ERR) {
1341 IWL_ERR(trans, "Microcode SW error detected. "
1342 " Restarting 0x%X.\n", inta);
1344 iwl_pcie_irq_handle_error(trans);
1345 handled |= CSR_INT_BIT_SW_ERR;
1348 /* uCode wakes up after power-down sleep */
1349 if (inta & CSR_INT_BIT_WAKEUP) {
1350 IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
1351 iwl_pcie_rxq_check_wrptr(trans);
1352 iwl_pcie_txq_check_wrptrs(trans);
1354 isr_stats->wakeup++;
1356 handled |= CSR_INT_BIT_WAKEUP;
1359 /* All uCode command responses, including Tx command responses,
1360 * Rx "responses" (frame-received notification), and other
1361 * notifications from uCode come through here*/
1362 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX |
1363 CSR_INT_BIT_RX_PERIODIC)) {
1364 IWL_DEBUG_ISR(trans, "Rx interrupt\n");
1365 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) {
1366 handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX);
1367 iwl_write32(trans, CSR_FH_INT_STATUS,
1368 CSR_FH_INT_RX_MASK);
1370 if (inta & CSR_INT_BIT_RX_PERIODIC) {
1371 handled |= CSR_INT_BIT_RX_PERIODIC;
1373 CSR_INT, CSR_INT_BIT_RX_PERIODIC);
1375 /* Sending RX interrupt require many steps to be done in the
1377 * 1- write interrupt to current index in ICT table.
1379 * 3- update RX shared data to indicate last write index.
1380 * 4- send interrupt.
1381 * This could lead to RX race, driver could receive RX interrupt
1382 * but the shared data changes does not reflect this;
1383 * periodic interrupt will detect any dangling Rx activity.
1386 /* Disable periodic interrupt; we use it as just a one-shot. */
1387 iwl_write8(trans, CSR_INT_PERIODIC_REG,
1388 CSR_INT_PERIODIC_DIS);
1391 * Enable periodic interrupt in 8 msec only if we received
1392 * real RX interrupt (instead of just periodic int), to catch
1393 * any dangling Rx interrupt. If it was just the periodic
1394 * interrupt, there was no dangling Rx activity, and no need
1395 * to extend the periodic interrupt; one-shot is enough.
1397 if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX))
1398 iwl_write8(trans, CSR_INT_PERIODIC_REG,
1399 CSR_INT_PERIODIC_ENA);
1404 iwl_pcie_rx_handle(trans);
1408 /* This "Tx" DMA channel is used only for loading uCode */
1409 if (inta & CSR_INT_BIT_FH_TX) {
1410 iwl_write32(trans, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
1411 IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
1413 handled |= CSR_INT_BIT_FH_TX;
1414 /* Wake up uCode load routine, now that load is complete */
1415 trans_pcie->ucode_write_complete = true;
1416 wake_up(&trans_pcie->ucode_write_waitq);
1419 if (inta & ~handled) {
1420 IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
1421 isr_stats->unhandled++;
1424 if (inta & ~(trans_pcie->inta_mask)) {
1425 IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n",
1426 inta & ~trans_pcie->inta_mask);
1429 /* Re-enable all interrupts */
1430 /* only Re-enable if disabled by irq */
1431 if (test_bit(STATUS_INT_ENABLED, &trans->status))
1432 iwl_enable_interrupts(trans);
1433 /* Re-enable RF_KILL if it occurred */
1434 else if (handled & CSR_INT_BIT_RF_KILL)
1435 iwl_enable_rfkill_int(trans);
1438 lock_map_release(&trans->sync_cmd_lockdep_map);
1442 /******************************************************************************
1446 ******************************************************************************/
1448 /* Free dram table */
1449 void iwl_pcie_free_ict(struct iwl_trans *trans)
1451 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1453 if (trans_pcie->ict_tbl) {
1454 dma_free_coherent(trans->dev, ICT_SIZE,
1455 trans_pcie->ict_tbl,
1456 trans_pcie->ict_tbl_dma);
1457 trans_pcie->ict_tbl = NULL;
1458 trans_pcie->ict_tbl_dma = 0;
1463 * allocate dram shared table, it is an aligned memory
1464 * block of ICT_SIZE.
1465 * also reset all data related to ICT table interrupt.
1467 int iwl_pcie_alloc_ict(struct iwl_trans *trans)
1469 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1471 trans_pcie->ict_tbl =
1472 dma_zalloc_coherent(trans->dev, ICT_SIZE,
1473 &trans_pcie->ict_tbl_dma,
1475 if (!trans_pcie->ict_tbl)
1478 /* just an API sanity check ... it is guaranteed to be aligned */
1479 if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) {
1480 iwl_pcie_free_ict(trans);
1484 IWL_DEBUG_ISR(trans, "ict dma addr %Lx ict vir addr %p\n",
1485 (unsigned long long)trans_pcie->ict_tbl_dma,
1486 trans_pcie->ict_tbl);
1491 /* Device is going up inform it about using ICT interrupt table,
1492 * also we need to tell the driver to start using ICT interrupt.
1494 void iwl_pcie_reset_ict(struct iwl_trans *trans)
1496 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1499 if (!trans_pcie->ict_tbl)
1502 spin_lock(&trans_pcie->irq_lock);
1503 iwl_disable_interrupts(trans);
1505 memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
1507 val = trans_pcie->ict_tbl_dma >> ICT_SHIFT;
1509 val |= CSR_DRAM_INT_TBL_ENABLE |
1510 CSR_DRAM_INIT_TBL_WRAP_CHECK |
1511 CSR_DRAM_INIT_TBL_WRITE_POINTER;
1513 IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val);
1515 iwl_write32(trans, CSR_DRAM_INT_TBL_REG, val);
1516 trans_pcie->use_ict = true;
1517 trans_pcie->ict_index = 0;
1518 iwl_write32(trans, CSR_INT, trans_pcie->inta_mask);
1519 iwl_enable_interrupts(trans);
1520 spin_unlock(&trans_pcie->irq_lock);
1523 /* Device is going down disable ict interrupt usage */
1524 void iwl_pcie_disable_ict(struct iwl_trans *trans)
1526 struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1528 spin_lock(&trans_pcie->irq_lock);
1529 trans_pcie->use_ict = false;
1530 spin_unlock(&trans_pcie->irq_lock);
1533 irqreturn_t iwl_pcie_isr(int irq, void *data)
1535 struct iwl_trans *trans = data;
1540 /* Disable (but don't clear!) interrupts here to avoid
1541 * back-to-back ISRs and sporadic interrupts from our NIC.
1542 * If we have something to service, the tasklet will re-enable ints.
1543 * If we *don't* have something, we'll re-enable before leaving here.
1545 iwl_write32(trans, CSR_INT_MASK, 0x00000000);
1547 return IRQ_WAKE_THREAD;