1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright (C) 2003-2014, 2018-2021 Intel Corporation
4  * Copyright (C) 2013-2015 Intel Mobile Communications GmbH
5  * Copyright (C) 2016-2017 Intel Deutschland GmbH
6  */
7 #include <linux/sched.h>
8 #include <linux/wait.h>
9 #include <linux/gfp.h>
10 
11 #include "iwl-prph.h"
12 #include "iwl-io.h"
13 #include "internal.h"
14 #include "iwl-op-mode.h"
15 #include "iwl-context-info-gen3.h"
16 
17 /******************************************************************************
18  *
19  * RX path functions
20  *
21  ******************************************************************************/
22 
23 /*
24  * Rx theory of operation
25  *
26  * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
27  * each of which point to Receive Buffers to be filled by the NIC.  These get
28  * used not only for Rx frames, but for any command response or notification
29  * from the NIC.  The driver and NIC manage the Rx buffers by means
30  * of indexes into the circular buffer.
31  *
32  * Rx Queue Indexes
33  * The host/firmware share two index registers for managing the Rx buffers.
34  *
35  * The READ index maps to the first position that the firmware may be writing
36  * to -- the driver can read up to (but not including) this position and get
37  * good data.
38  * The READ index is managed by the firmware once the card is enabled.
39  *
40  * The WRITE index maps to the last position the driver has read from -- the
41  * position preceding WRITE is the last slot the firmware can place a packet.
42  *
43  * The queue is empty (no good data) if WRITE = READ - 1, and is full if
44  * WRITE = READ.
45  *
46  * During initialization, the host sets up the READ queue position to the first
47  * INDEX position, and WRITE to the last (READ - 1 wrapped)
48  *
49  * When the firmware places a packet in a buffer, it will advance the READ index
50  * and fire the RX interrupt.  The driver can then query the READ index and
51  * process as many packets as possible, moving the WRITE index forward as it
52  * resets the Rx queue buffers with new memory.
53  *
54  * The management in the driver is as follows:
55  * + A list of pre-allocated RBDs is stored in iwl->rxq->rx_free.
56  *   When the interrupt handler is called, the request is processed.
57  *   The page is either stolen - transferred to the upper layer
58  *   or reused - added immediately to the iwl->rxq->rx_free list.
59  * + When the page is stolen - the driver updates the matching queue's used
60  *   count, detaches the RBD and transfers it to the queue used list.
61  *   When there are two used RBDs - they are transferred to the allocator empty
62  *   list. Work is then scheduled for the allocator to start allocating
63  *   eight buffers.
64  *   When there are another 6 used RBDs - they are transferred to the allocator
65  *   empty list and the driver tries to claim the pre-allocated buffers and
66  *   add them to iwl->rxq->rx_free. If it fails - it continues to claim them
67  *   until ready.
68  *   When there are 8+ buffers in the free list - either from allocation or from
69  *   8 reused unstolen pages - restock is called to update the FW and indexes.
70  * + In order to make sure the allocator always has RBDs to use for allocation
71  *   the allocator has initial pool in the size of num_queues*(8-2) - the
72  *   maximum missing RBDs per allocation request (request posted with 2
73  *    empty RBDs, there is no guarantee when the other 6 RBDs are supplied).
74  *   The queues supplies the recycle of the rest of the RBDs.
75  * + A received packet is processed and handed to the kernel network stack,
76  *   detached from the iwl->rxq.  The driver 'processed' index is updated.
77  * + If there are no allocated buffers in iwl->rxq->rx_free,
78  *   the READ INDEX is not incremented and iwl->status(RX_STALLED) is set.
79  *   If there were enough free buffers and RX_STALLED is set it is cleared.
80  *
81  *
82  * Driver sequence:
83  *
84  * iwl_rxq_alloc()            Allocates rx_free
85  * iwl_pcie_rx_replenish()    Replenishes rx_free list from rx_used, and calls
86  *                            iwl_pcie_rxq_restock.
87  *                            Used only during initialization.
88  * iwl_pcie_rxq_restock()     Moves available buffers from rx_free into Rx
89  *                            queue, updates firmware pointers, and updates
90  *                            the WRITE index.
91  * iwl_pcie_rx_allocator()     Background work for allocating pages.
92  *
93  * -- enable interrupts --
94  * ISR - iwl_rx()             Detach iwl_rx_mem_buffers from pool up to the
95  *                            READ INDEX, detaching the SKB from the pool.
96  *                            Moves the packet buffer from queue to rx_used.
97  *                            Posts and claims requests to the allocator.
98  *                            Calls iwl_pcie_rxq_restock to refill any empty
99  *                            slots.
100  *
101  * RBD life-cycle:
102  *
103  * Init:
104  * rxq.pool -> rxq.rx_used -> rxq.rx_free -> rxq.queue
105  *
106  * Regular Receive interrupt:
107  * Page Stolen:
108  * rxq.queue -> rxq.rx_used -> allocator.rbd_empty ->
109  * allocator.rbd_allocated -> rxq.rx_free -> rxq.queue
110  * Page not Stolen:
111  * rxq.queue -> rxq.rx_free -> rxq.queue
112  * ...
113  *
114  */
115 
116 /*
117  * iwl_rxq_space - Return number of free slots available in queue.
118  */
119 static int iwl_rxq_space(const struct iwl_rxq *rxq)
120 {
121 	/* Make sure rx queue size is a power of 2 */
122 	WARN_ON(rxq->queue_size & (rxq->queue_size - 1));
123 
124 	/*
125 	 * There can be up to (RX_QUEUE_SIZE - 1) free slots, to avoid ambiguity
126 	 * between empty and completely full queues.
127 	 * The following is equivalent to modulo by RX_QUEUE_SIZE and is well
128 	 * defined for negative dividends.
129 	 */
130 	return (rxq->read - rxq->write - 1) & (rxq->queue_size - 1);
131 }
132 
133 /*
134  * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
135  */
136 static inline __le32 iwl_pcie_dma_addr2rbd_ptr(dma_addr_t dma_addr)
137 {
138 	return cpu_to_le32((u32)(dma_addr >> 8));
139 }
140 
141 /*
142  * iwl_pcie_rx_stop - stops the Rx DMA
143  */
144 int iwl_pcie_rx_stop(struct iwl_trans *trans)
145 {
146 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {
147 		/* TODO: remove this once fw does it */
148 		iwl_write_umac_prph(trans, RFH_RXF_DMA_CFG_GEN3, 0);
149 		return iwl_poll_umac_prph_bit(trans, RFH_GEN_STATUS_GEN3,
150 					      RXF_DMA_IDLE, RXF_DMA_IDLE, 1000);
151 	} else if (trans->trans_cfg->mq_rx_supported) {
152 		iwl_write_prph(trans, RFH_RXF_DMA_CFG, 0);
153 		return iwl_poll_prph_bit(trans, RFH_GEN_STATUS,
154 					   RXF_DMA_IDLE, RXF_DMA_IDLE, 1000);
155 	} else {
156 		iwl_write_direct32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
157 		return iwl_poll_direct_bit(trans, FH_MEM_RSSR_RX_STATUS_REG,
158 					   FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE,
159 					   1000);
160 	}
161 }
162 
163 /*
164  * iwl_pcie_rxq_inc_wr_ptr - Update the write pointer for the RX queue
165  */
166 static void iwl_pcie_rxq_inc_wr_ptr(struct iwl_trans *trans,
167 				    struct iwl_rxq *rxq)
168 {
169 	u32 reg;
170 
171 	lockdep_assert_held(&rxq->lock);
172 
173 	/*
174 	 * explicitly wake up the NIC if:
175 	 * 1. shadow registers aren't enabled
176 	 * 2. there is a chance that the NIC is asleep
177 	 */
178 	if (!trans->trans_cfg->base_params->shadow_reg_enable &&
179 	    test_bit(STATUS_TPOWER_PMI, &trans->status)) {
180 		reg = iwl_read32(trans, CSR_UCODE_DRV_GP1);
181 
182 		if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
183 			IWL_DEBUG_INFO(trans, "Rx queue requesting wakeup, GP1 = 0x%x\n",
184 				       reg);
185 			iwl_set_bit(trans, CSR_GP_CNTRL,
186 				    CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
187 			rxq->need_update = true;
188 			return;
189 		}
190 	}
191 
192 	rxq->write_actual = round_down(rxq->write, 8);
193 	if (trans->trans_cfg->mq_rx_supported)
194 		iwl_write32(trans, RFH_Q_FRBDCB_WIDX_TRG(rxq->id),
195 			    rxq->write_actual);
196 	else
197 		iwl_write32(trans, FH_RSCSR_CHNL0_WPTR, rxq->write_actual);
198 }
199 
200 static void iwl_pcie_rxq_check_wrptr(struct iwl_trans *trans)
201 {
202 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
203 	int i;
204 
205 	for (i = 0; i < trans->num_rx_queues; i++) {
206 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
207 
208 		if (!rxq->need_update)
209 			continue;
210 		spin_lock_bh(&rxq->lock);
211 		iwl_pcie_rxq_inc_wr_ptr(trans, rxq);
212 		rxq->need_update = false;
213 		spin_unlock_bh(&rxq->lock);
214 	}
215 }
216 
217 static void iwl_pcie_restock_bd(struct iwl_trans *trans,
218 				struct iwl_rxq *rxq,
219 				struct iwl_rx_mem_buffer *rxb)
220 {
221 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {
222 		struct iwl_rx_transfer_desc *bd = rxq->bd;
223 
224 		BUILD_BUG_ON(sizeof(*bd) != 2 * sizeof(u64));
225 
226 		bd[rxq->write].addr = cpu_to_le64(rxb->page_dma);
227 		bd[rxq->write].rbid = cpu_to_le16(rxb->vid);
228 	} else {
229 		__le64 *bd = rxq->bd;
230 
231 		bd[rxq->write] = cpu_to_le64(rxb->page_dma | rxb->vid);
232 	}
233 
234 	IWL_DEBUG_RX(trans, "Assigned virtual RB ID %u to queue %d index %d\n",
235 		     (u32)rxb->vid, rxq->id, rxq->write);
236 }
237 
238 /*
239  * iwl_pcie_rxmq_restock - restock implementation for multi-queue rx
240  */
241 static void iwl_pcie_rxmq_restock(struct iwl_trans *trans,
242 				  struct iwl_rxq *rxq)
243 {
244 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
245 	struct iwl_rx_mem_buffer *rxb;
246 
247 	/*
248 	 * If the device isn't enabled - no need to try to add buffers...
249 	 * This can happen when we stop the device and still have an interrupt
250 	 * pending. We stop the APM before we sync the interrupts because we
251 	 * have to (see comment there). On the other hand, since the APM is
252 	 * stopped, we cannot access the HW (in particular not prph).
253 	 * So don't try to restock if the APM has been already stopped.
254 	 */
255 	if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
256 		return;
257 
258 	spin_lock_bh(&rxq->lock);
259 	while (rxq->free_count) {
260 		/* Get next free Rx buffer, remove from free list */
261 		rxb = list_first_entry(&rxq->rx_free, struct iwl_rx_mem_buffer,
262 				       list);
263 		list_del(&rxb->list);
264 		rxb->invalid = false;
265 		/* some low bits are expected to be unset (depending on hw) */
266 		WARN_ON(rxb->page_dma & trans_pcie->supported_dma_mask);
267 		/* Point to Rx buffer via next RBD in circular buffer */
268 		iwl_pcie_restock_bd(trans, rxq, rxb);
269 		rxq->write = (rxq->write + 1) & (rxq->queue_size - 1);
270 		rxq->free_count--;
271 	}
272 	spin_unlock_bh(&rxq->lock);
273 
274 	/*
275 	 * If we've added more space for the firmware to place data, tell it.
276 	 * Increment device's write pointer in multiples of 8.
277 	 */
278 	if (rxq->write_actual != (rxq->write & ~0x7)) {
279 		spin_lock_bh(&rxq->lock);
280 		iwl_pcie_rxq_inc_wr_ptr(trans, rxq);
281 		spin_unlock_bh(&rxq->lock);
282 	}
283 }
284 
285 /*
286  * iwl_pcie_rxsq_restock - restock implementation for single queue rx
287  */
288 static void iwl_pcie_rxsq_restock(struct iwl_trans *trans,
289 				  struct iwl_rxq *rxq)
290 {
291 	struct iwl_rx_mem_buffer *rxb;
292 
293 	/*
294 	 * If the device isn't enabled - not need to try to add buffers...
295 	 * This can happen when we stop the device and still have an interrupt
296 	 * pending. We stop the APM before we sync the interrupts because we
297 	 * have to (see comment there). On the other hand, since the APM is
298 	 * stopped, we cannot access the HW (in particular not prph).
299 	 * So don't try to restock if the APM has been already stopped.
300 	 */
301 	if (!test_bit(STATUS_DEVICE_ENABLED, &trans->status))
302 		return;
303 
304 	spin_lock_bh(&rxq->lock);
305 	while ((iwl_rxq_space(rxq) > 0) && (rxq->free_count)) {
306 		__le32 *bd = (__le32 *)rxq->bd;
307 		/* The overwritten rxb must be a used one */
308 		rxb = rxq->queue[rxq->write];
309 		BUG_ON(rxb && rxb->page);
310 
311 		/* Get next free Rx buffer, remove from free list */
312 		rxb = list_first_entry(&rxq->rx_free, struct iwl_rx_mem_buffer,
313 				       list);
314 		list_del(&rxb->list);
315 		rxb->invalid = false;
316 
317 		/* Point to Rx buffer via next RBD in circular buffer */
318 		bd[rxq->write] = iwl_pcie_dma_addr2rbd_ptr(rxb->page_dma);
319 		rxq->queue[rxq->write] = rxb;
320 		rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
321 		rxq->free_count--;
322 	}
323 	spin_unlock_bh(&rxq->lock);
324 
325 	/* If we've added more space for the firmware to place data, tell it.
326 	 * Increment device's write pointer in multiples of 8. */
327 	if (rxq->write_actual != (rxq->write & ~0x7)) {
328 		spin_lock_bh(&rxq->lock);
329 		iwl_pcie_rxq_inc_wr_ptr(trans, rxq);
330 		spin_unlock_bh(&rxq->lock);
331 	}
332 }
333 
334 /*
335  * iwl_pcie_rxq_restock - refill RX queue from pre-allocated pool
336  *
337  * If there are slots in the RX queue that need to be restocked,
338  * and we have free pre-allocated buffers, fill the ranks as much
339  * as we can, pulling from rx_free.
340  *
341  * This moves the 'write' index forward to catch up with 'processed', and
342  * also updates the memory address in the firmware to reference the new
343  * target buffer.
344  */
345 static
346 void iwl_pcie_rxq_restock(struct iwl_trans *trans, struct iwl_rxq *rxq)
347 {
348 	if (trans->trans_cfg->mq_rx_supported)
349 		iwl_pcie_rxmq_restock(trans, rxq);
350 	else
351 		iwl_pcie_rxsq_restock(trans, rxq);
352 }
353 
354 /*
355  * iwl_pcie_rx_alloc_page - allocates and returns a page.
356  *
357  */
358 static struct page *iwl_pcie_rx_alloc_page(struct iwl_trans *trans,
359 					   u32 *offset, gfp_t priority)
360 {
361 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
362 	unsigned int rbsize = iwl_trans_get_rb_size(trans_pcie->rx_buf_size);
363 	unsigned int allocsize = PAGE_SIZE << trans_pcie->rx_page_order;
364 	struct page *page;
365 	gfp_t gfp_mask = priority;
366 
367 	if (trans_pcie->rx_page_order > 0)
368 		gfp_mask |= __GFP_COMP;
369 
370 	if (trans_pcie->alloc_page) {
371 		spin_lock_bh(&trans_pcie->alloc_page_lock);
372 		/* recheck */
373 		if (trans_pcie->alloc_page) {
374 			*offset = trans_pcie->alloc_page_used;
375 			page = trans_pcie->alloc_page;
376 			trans_pcie->alloc_page_used += rbsize;
377 			if (trans_pcie->alloc_page_used >= allocsize)
378 				trans_pcie->alloc_page = NULL;
379 			else
380 				get_page(page);
381 			spin_unlock_bh(&trans_pcie->alloc_page_lock);
382 			return page;
383 		}
384 		spin_unlock_bh(&trans_pcie->alloc_page_lock);
385 	}
386 
387 	/* Alloc a new receive buffer */
388 	page = alloc_pages(gfp_mask, trans_pcie->rx_page_order);
389 	if (!page) {
390 		if (net_ratelimit())
391 			IWL_DEBUG_INFO(trans, "alloc_pages failed, order: %d\n",
392 				       trans_pcie->rx_page_order);
393 		/*
394 		 * Issue an error if we don't have enough pre-allocated
395 		  * buffers.
396 		 */
397 		if (!(gfp_mask & __GFP_NOWARN) && net_ratelimit())
398 			IWL_CRIT(trans,
399 				 "Failed to alloc_pages\n");
400 		return NULL;
401 	}
402 
403 	if (2 * rbsize <= allocsize) {
404 		spin_lock_bh(&trans_pcie->alloc_page_lock);
405 		if (!trans_pcie->alloc_page) {
406 			get_page(page);
407 			trans_pcie->alloc_page = page;
408 			trans_pcie->alloc_page_used = rbsize;
409 		}
410 		spin_unlock_bh(&trans_pcie->alloc_page_lock);
411 	}
412 
413 	*offset = 0;
414 	return page;
415 }
416 
417 /*
418  * iwl_pcie_rxq_alloc_rbs - allocate a page for each used RBD
419  *
420  * A used RBD is an Rx buffer that has been given to the stack. To use it again
421  * a page must be allocated and the RBD must point to the page. This function
422  * doesn't change the HW pointer but handles the list of pages that is used by
423  * iwl_pcie_rxq_restock. The latter function will update the HW to use the newly
424  * allocated buffers.
425  */
426 void iwl_pcie_rxq_alloc_rbs(struct iwl_trans *trans, gfp_t priority,
427 			    struct iwl_rxq *rxq)
428 {
429 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
430 	struct iwl_rx_mem_buffer *rxb;
431 	struct page *page;
432 
433 	while (1) {
434 		unsigned int offset;
435 
436 		spin_lock_bh(&rxq->lock);
437 		if (list_empty(&rxq->rx_used)) {
438 			spin_unlock_bh(&rxq->lock);
439 			return;
440 		}
441 		spin_unlock_bh(&rxq->lock);
442 
443 		page = iwl_pcie_rx_alloc_page(trans, &offset, priority);
444 		if (!page)
445 			return;
446 
447 		spin_lock_bh(&rxq->lock);
448 
449 		if (list_empty(&rxq->rx_used)) {
450 			spin_unlock_bh(&rxq->lock);
451 			__free_pages(page, trans_pcie->rx_page_order);
452 			return;
453 		}
454 		rxb = list_first_entry(&rxq->rx_used, struct iwl_rx_mem_buffer,
455 				       list);
456 		list_del(&rxb->list);
457 		spin_unlock_bh(&rxq->lock);
458 
459 		BUG_ON(rxb->page);
460 		rxb->page = page;
461 		rxb->offset = offset;
462 		/* Get physical address of the RB */
463 		rxb->page_dma =
464 			dma_map_page(trans->dev, page, rxb->offset,
465 				     trans_pcie->rx_buf_bytes,
466 				     DMA_FROM_DEVICE);
467 		if (dma_mapping_error(trans->dev, rxb->page_dma)) {
468 			rxb->page = NULL;
469 			spin_lock_bh(&rxq->lock);
470 			list_add(&rxb->list, &rxq->rx_used);
471 			spin_unlock_bh(&rxq->lock);
472 			__free_pages(page, trans_pcie->rx_page_order);
473 			return;
474 		}
475 
476 		spin_lock_bh(&rxq->lock);
477 
478 		list_add_tail(&rxb->list, &rxq->rx_free);
479 		rxq->free_count++;
480 
481 		spin_unlock_bh(&rxq->lock);
482 	}
483 }
484 
485 void iwl_pcie_free_rbs_pool(struct iwl_trans *trans)
486 {
487 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
488 	int i;
489 
490 	for (i = 0; i < RX_POOL_SIZE(trans_pcie->num_rx_bufs); i++) {
491 		if (!trans_pcie->rx_pool[i].page)
492 			continue;
493 		dma_unmap_page(trans->dev, trans_pcie->rx_pool[i].page_dma,
494 			       trans_pcie->rx_buf_bytes, DMA_FROM_DEVICE);
495 		__free_pages(trans_pcie->rx_pool[i].page,
496 			     trans_pcie->rx_page_order);
497 		trans_pcie->rx_pool[i].page = NULL;
498 	}
499 }
500 
501 /*
502  * iwl_pcie_rx_allocator - Allocates pages in the background for RX queues
503  *
504  * Allocates for each received request 8 pages
505  * Called as a scheduled work item.
506  */
507 static void iwl_pcie_rx_allocator(struct iwl_trans *trans)
508 {
509 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
510 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
511 	struct list_head local_empty;
512 	int pending = atomic_read(&rba->req_pending);
513 
514 	IWL_DEBUG_TPT(trans, "Pending allocation requests = %d\n", pending);
515 
516 	/* If we were scheduled - there is at least one request */
517 	spin_lock_bh(&rba->lock);
518 	/* swap out the rba->rbd_empty to a local list */
519 	list_replace_init(&rba->rbd_empty, &local_empty);
520 	spin_unlock_bh(&rba->lock);
521 
522 	while (pending) {
523 		int i;
524 		LIST_HEAD(local_allocated);
525 		gfp_t gfp_mask = GFP_KERNEL;
526 
527 		/* Do not post a warning if there are only a few requests */
528 		if (pending < RX_PENDING_WATERMARK)
529 			gfp_mask |= __GFP_NOWARN;
530 
531 		for (i = 0; i < RX_CLAIM_REQ_ALLOC;) {
532 			struct iwl_rx_mem_buffer *rxb;
533 			struct page *page;
534 
535 			/* List should never be empty - each reused RBD is
536 			 * returned to the list, and initial pool covers any
537 			 * possible gap between the time the page is allocated
538 			 * to the time the RBD is added.
539 			 */
540 			BUG_ON(list_empty(&local_empty));
541 			/* Get the first rxb from the rbd list */
542 			rxb = list_first_entry(&local_empty,
543 					       struct iwl_rx_mem_buffer, list);
544 			BUG_ON(rxb->page);
545 
546 			/* Alloc a new receive buffer */
547 			page = iwl_pcie_rx_alloc_page(trans, &rxb->offset,
548 						      gfp_mask);
549 			if (!page)
550 				continue;
551 			rxb->page = page;
552 
553 			/* Get physical address of the RB */
554 			rxb->page_dma = dma_map_page(trans->dev, page,
555 						     rxb->offset,
556 						     trans_pcie->rx_buf_bytes,
557 						     DMA_FROM_DEVICE);
558 			if (dma_mapping_error(trans->dev, rxb->page_dma)) {
559 				rxb->page = NULL;
560 				__free_pages(page, trans_pcie->rx_page_order);
561 				continue;
562 			}
563 
564 			/* move the allocated entry to the out list */
565 			list_move(&rxb->list, &local_allocated);
566 			i++;
567 		}
568 
569 		atomic_dec(&rba->req_pending);
570 		pending--;
571 
572 		if (!pending) {
573 			pending = atomic_read(&rba->req_pending);
574 			if (pending)
575 				IWL_DEBUG_TPT(trans,
576 					      "Got more pending allocation requests = %d\n",
577 					      pending);
578 		}
579 
580 		spin_lock_bh(&rba->lock);
581 		/* add the allocated rbds to the allocator allocated list */
582 		list_splice_tail(&local_allocated, &rba->rbd_allocated);
583 		/* get more empty RBDs for current pending requests */
584 		list_splice_tail_init(&rba->rbd_empty, &local_empty);
585 		spin_unlock_bh(&rba->lock);
586 
587 		atomic_inc(&rba->req_ready);
588 
589 	}
590 
591 	spin_lock_bh(&rba->lock);
592 	/* return unused rbds to the allocator empty list */
593 	list_splice_tail(&local_empty, &rba->rbd_empty);
594 	spin_unlock_bh(&rba->lock);
595 
596 	IWL_DEBUG_TPT(trans, "%s, exit.\n", __func__);
597 }
598 
599 /*
600  * iwl_pcie_rx_allocator_get - returns the pre-allocated pages
601 .*
602 .* Called by queue when the queue posted allocation request and
603  * has freed 8 RBDs in order to restock itself.
604  * This function directly moves the allocated RBs to the queue's ownership
605  * and updates the relevant counters.
606  */
607 static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans,
608 				      struct iwl_rxq *rxq)
609 {
610 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
611 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
612 	int i;
613 
614 	lockdep_assert_held(&rxq->lock);
615 
616 	/*
617 	 * atomic_dec_if_positive returns req_ready - 1 for any scenario.
618 	 * If req_ready is 0 atomic_dec_if_positive will return -1 and this
619 	 * function will return early, as there are no ready requests.
620 	 * atomic_dec_if_positive will perofrm the *actual* decrement only if
621 	 * req_ready > 0, i.e. - there are ready requests and the function
622 	 * hands one request to the caller.
623 	 */
624 	if (atomic_dec_if_positive(&rba->req_ready) < 0)
625 		return;
626 
627 	spin_lock(&rba->lock);
628 	for (i = 0; i < RX_CLAIM_REQ_ALLOC; i++) {
629 		/* Get next free Rx buffer, remove it from free list */
630 		struct iwl_rx_mem_buffer *rxb =
631 			list_first_entry(&rba->rbd_allocated,
632 					 struct iwl_rx_mem_buffer, list);
633 
634 		list_move(&rxb->list, &rxq->rx_free);
635 	}
636 	spin_unlock(&rba->lock);
637 
638 	rxq->used_count -= RX_CLAIM_REQ_ALLOC;
639 	rxq->free_count += RX_CLAIM_REQ_ALLOC;
640 }
641 
642 void iwl_pcie_rx_allocator_work(struct work_struct *data)
643 {
644 	struct iwl_rb_allocator *rba_p =
645 		container_of(data, struct iwl_rb_allocator, rx_alloc);
646 	struct iwl_trans_pcie *trans_pcie =
647 		container_of(rba_p, struct iwl_trans_pcie, rba);
648 
649 	iwl_pcie_rx_allocator(trans_pcie->trans);
650 }
651 
652 static int iwl_pcie_free_bd_size(struct iwl_trans *trans, bool use_rx_td)
653 {
654 	struct iwl_rx_transfer_desc *rx_td;
655 
656 	if (use_rx_td)
657 		return sizeof(*rx_td);
658 	else
659 		return trans->trans_cfg->mq_rx_supported ? sizeof(__le64) :
660 			sizeof(__le32);
661 }
662 
663 static void iwl_pcie_free_rxq_dma(struct iwl_trans *trans,
664 				  struct iwl_rxq *rxq)
665 {
666 	struct device *dev = trans->dev;
667 	bool use_rx_td = (trans->trans_cfg->device_family >=
668 			  IWL_DEVICE_FAMILY_AX210);
669 	int free_size = iwl_pcie_free_bd_size(trans, use_rx_td);
670 
671 	if (rxq->bd)
672 		dma_free_coherent(trans->dev,
673 				  free_size * rxq->queue_size,
674 				  rxq->bd, rxq->bd_dma);
675 	rxq->bd_dma = 0;
676 	rxq->bd = NULL;
677 
678 	rxq->rb_stts_dma = 0;
679 	rxq->rb_stts = NULL;
680 
681 	if (rxq->used_bd)
682 		dma_free_coherent(trans->dev,
683 				  (use_rx_td ? sizeof(*rxq->cd) :
684 				   sizeof(__le32)) * rxq->queue_size,
685 				  rxq->used_bd, rxq->used_bd_dma);
686 	rxq->used_bd_dma = 0;
687 	rxq->used_bd = NULL;
688 
689 	if (trans->trans_cfg->device_family < IWL_DEVICE_FAMILY_AX210)
690 		return;
691 
692 	if (rxq->tr_tail)
693 		dma_free_coherent(dev, sizeof(__le16),
694 				  rxq->tr_tail, rxq->tr_tail_dma);
695 	rxq->tr_tail_dma = 0;
696 	rxq->tr_tail = NULL;
697 
698 	if (rxq->cr_tail)
699 		dma_free_coherent(dev, sizeof(__le16),
700 				  rxq->cr_tail, rxq->cr_tail_dma);
701 	rxq->cr_tail_dma = 0;
702 	rxq->cr_tail = NULL;
703 }
704 
705 static int iwl_pcie_alloc_rxq_dma(struct iwl_trans *trans,
706 				  struct iwl_rxq *rxq)
707 {
708 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
709 	struct device *dev = trans->dev;
710 	int i;
711 	int free_size;
712 	bool use_rx_td = (trans->trans_cfg->device_family >=
713 			  IWL_DEVICE_FAMILY_AX210);
714 	size_t rb_stts_size = use_rx_td ? sizeof(__le16) :
715 			      sizeof(struct iwl_rb_status);
716 
717 	spin_lock_init(&rxq->lock);
718 	if (trans->trans_cfg->mq_rx_supported)
719 		rxq->queue_size = trans->cfg->num_rbds;
720 	else
721 		rxq->queue_size = RX_QUEUE_SIZE;
722 
723 	free_size = iwl_pcie_free_bd_size(trans, use_rx_td);
724 
725 	/*
726 	 * Allocate the circular buffer of Read Buffer Descriptors
727 	 * (RBDs)
728 	 */
729 	rxq->bd = dma_alloc_coherent(dev, free_size * rxq->queue_size,
730 				     &rxq->bd_dma, GFP_KERNEL);
731 	if (!rxq->bd)
732 		goto err;
733 
734 	if (trans->trans_cfg->mq_rx_supported) {
735 		rxq->used_bd = dma_alloc_coherent(dev,
736 						  (use_rx_td ? sizeof(*rxq->cd) : sizeof(__le32)) * rxq->queue_size,
737 						  &rxq->used_bd_dma,
738 						  GFP_KERNEL);
739 		if (!rxq->used_bd)
740 			goto err;
741 	}
742 
743 	rxq->rb_stts = trans_pcie->base_rb_stts + rxq->id * rb_stts_size;
744 	rxq->rb_stts_dma =
745 		trans_pcie->base_rb_stts_dma + rxq->id * rb_stts_size;
746 
747 	if (!use_rx_td)
748 		return 0;
749 
750 	/* Allocate the driver's pointer to TR tail */
751 	rxq->tr_tail = dma_alloc_coherent(dev, sizeof(__le16),
752 					  &rxq->tr_tail_dma, GFP_KERNEL);
753 	if (!rxq->tr_tail)
754 		goto err;
755 
756 	/* Allocate the driver's pointer to CR tail */
757 	rxq->cr_tail = dma_alloc_coherent(dev, sizeof(__le16),
758 					  &rxq->cr_tail_dma, GFP_KERNEL);
759 	if (!rxq->cr_tail)
760 		goto err;
761 
762 	return 0;
763 
764 err:
765 	for (i = 0; i < trans->num_rx_queues; i++) {
766 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
767 
768 		iwl_pcie_free_rxq_dma(trans, rxq);
769 	}
770 
771 	return -ENOMEM;
772 }
773 
774 static int iwl_pcie_rx_alloc(struct iwl_trans *trans)
775 {
776 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
777 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
778 	int i, ret;
779 	size_t rb_stts_size = trans->trans_cfg->device_family >=
780 				IWL_DEVICE_FAMILY_AX210 ?
781 			      sizeof(__le16) : sizeof(struct iwl_rb_status);
782 
783 	if (WARN_ON(trans_pcie->rxq))
784 		return -EINVAL;
785 
786 	trans_pcie->rxq = kcalloc(trans->num_rx_queues, sizeof(struct iwl_rxq),
787 				  GFP_KERNEL);
788 	trans_pcie->rx_pool = kcalloc(RX_POOL_SIZE(trans_pcie->num_rx_bufs),
789 				      sizeof(trans_pcie->rx_pool[0]),
790 				      GFP_KERNEL);
791 	trans_pcie->global_table =
792 		kcalloc(RX_POOL_SIZE(trans_pcie->num_rx_bufs),
793 			sizeof(trans_pcie->global_table[0]),
794 			GFP_KERNEL);
795 	if (!trans_pcie->rxq || !trans_pcie->rx_pool ||
796 	    !trans_pcie->global_table) {
797 		ret = -ENOMEM;
798 		goto err;
799 	}
800 
801 	spin_lock_init(&rba->lock);
802 
803 	/*
804 	 * Allocate the driver's pointer to receive buffer status.
805 	 * Allocate for all queues continuously (HW requirement).
806 	 */
807 	trans_pcie->base_rb_stts =
808 			dma_alloc_coherent(trans->dev,
809 					   rb_stts_size * trans->num_rx_queues,
810 					   &trans_pcie->base_rb_stts_dma,
811 					   GFP_KERNEL);
812 	if (!trans_pcie->base_rb_stts) {
813 		ret = -ENOMEM;
814 		goto err;
815 	}
816 
817 	for (i = 0; i < trans->num_rx_queues; i++) {
818 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
819 
820 		rxq->id = i;
821 		ret = iwl_pcie_alloc_rxq_dma(trans, rxq);
822 		if (ret)
823 			goto err;
824 	}
825 	return 0;
826 
827 err:
828 	if (trans_pcie->base_rb_stts) {
829 		dma_free_coherent(trans->dev,
830 				  rb_stts_size * trans->num_rx_queues,
831 				  trans_pcie->base_rb_stts,
832 				  trans_pcie->base_rb_stts_dma);
833 		trans_pcie->base_rb_stts = NULL;
834 		trans_pcie->base_rb_stts_dma = 0;
835 	}
836 	kfree(trans_pcie->rx_pool);
837 	trans_pcie->rx_pool = NULL;
838 	kfree(trans_pcie->global_table);
839 	trans_pcie->global_table = NULL;
840 	kfree(trans_pcie->rxq);
841 	trans_pcie->rxq = NULL;
842 
843 	return ret;
844 }
845 
846 static void iwl_pcie_rx_hw_init(struct iwl_trans *trans, struct iwl_rxq *rxq)
847 {
848 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
849 	u32 rb_size;
850 	const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
851 
852 	switch (trans_pcie->rx_buf_size) {
853 	case IWL_AMSDU_4K:
854 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
855 		break;
856 	case IWL_AMSDU_8K:
857 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
858 		break;
859 	case IWL_AMSDU_12K:
860 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_12K;
861 		break;
862 	default:
863 		WARN_ON(1);
864 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
865 	}
866 
867 	if (!iwl_trans_grab_nic_access(trans))
868 		return;
869 
870 	/* Stop Rx DMA */
871 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
872 	/* reset and flush pointers */
873 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_RBDCB_WPTR, 0);
874 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_FLUSH_RB_REQ, 0);
875 	iwl_write32(trans, FH_RSCSR_CHNL0_RDPTR, 0);
876 
877 	/* Reset driver's Rx queue write index */
878 	iwl_write32(trans, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
879 
880 	/* Tell device where to find RBD circular buffer in DRAM */
881 	iwl_write32(trans, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
882 		    (u32)(rxq->bd_dma >> 8));
883 
884 	/* Tell device where in DRAM to update its Rx status */
885 	iwl_write32(trans, FH_RSCSR_CHNL0_STTS_WPTR_REG,
886 		    rxq->rb_stts_dma >> 4);
887 
888 	/* Enable Rx DMA
889 	 * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in
890 	 *      the credit mechanism in 5000 HW RX FIFO
891 	 * Direct rx interrupts to hosts
892 	 * Rx buffer size 4 or 8k or 12k
893 	 * RB timeout 0x10
894 	 * 256 RBDs
895 	 */
896 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG,
897 		    FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
898 		    FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY |
899 		    FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
900 		    rb_size |
901 		    (RX_RB_TIMEOUT << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS) |
902 		    (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));
903 
904 	iwl_trans_release_nic_access(trans);
905 
906 	/* Set interrupt coalescing timer to default (2048 usecs) */
907 	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
908 
909 	/* W/A for interrupt coalescing bug in 7260 and 3160 */
910 	if (trans->cfg->host_interrupt_operation_mode)
911 		iwl_set_bit(trans, CSR_INT_COALESCING, IWL_HOST_INT_OPER_MODE);
912 }
913 
914 static void iwl_pcie_rx_mq_hw_init(struct iwl_trans *trans)
915 {
916 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
917 	u32 rb_size, enabled = 0;
918 	int i;
919 
920 	switch (trans_pcie->rx_buf_size) {
921 	case IWL_AMSDU_2K:
922 		rb_size = RFH_RXF_DMA_RB_SIZE_2K;
923 		break;
924 	case IWL_AMSDU_4K:
925 		rb_size = RFH_RXF_DMA_RB_SIZE_4K;
926 		break;
927 	case IWL_AMSDU_8K:
928 		rb_size = RFH_RXF_DMA_RB_SIZE_8K;
929 		break;
930 	case IWL_AMSDU_12K:
931 		rb_size = RFH_RXF_DMA_RB_SIZE_12K;
932 		break;
933 	default:
934 		WARN_ON(1);
935 		rb_size = RFH_RXF_DMA_RB_SIZE_4K;
936 	}
937 
938 	if (!iwl_trans_grab_nic_access(trans))
939 		return;
940 
941 	/* Stop Rx DMA */
942 	iwl_write_prph_no_grab(trans, RFH_RXF_DMA_CFG, 0);
943 	/* disable free amd used rx queue operation */
944 	iwl_write_prph_no_grab(trans, RFH_RXF_RXQ_ACTIVE, 0);
945 
946 	for (i = 0; i < trans->num_rx_queues; i++) {
947 		/* Tell device where to find RBD free table in DRAM */
948 		iwl_write_prph64_no_grab(trans,
949 					 RFH_Q_FRBDCB_BA_LSB(i),
950 					 trans_pcie->rxq[i].bd_dma);
951 		/* Tell device where to find RBD used table in DRAM */
952 		iwl_write_prph64_no_grab(trans,
953 					 RFH_Q_URBDCB_BA_LSB(i),
954 					 trans_pcie->rxq[i].used_bd_dma);
955 		/* Tell device where in DRAM to update its Rx status */
956 		iwl_write_prph64_no_grab(trans,
957 					 RFH_Q_URBD_STTS_WPTR_LSB(i),
958 					 trans_pcie->rxq[i].rb_stts_dma);
959 		/* Reset device indice tables */
960 		iwl_write_prph_no_grab(trans, RFH_Q_FRBDCB_WIDX(i), 0);
961 		iwl_write_prph_no_grab(trans, RFH_Q_FRBDCB_RIDX(i), 0);
962 		iwl_write_prph_no_grab(trans, RFH_Q_URBDCB_WIDX(i), 0);
963 
964 		enabled |= BIT(i) | BIT(i + 16);
965 	}
966 
967 	/*
968 	 * Enable Rx DMA
969 	 * Rx buffer size 4 or 8k or 12k
970 	 * Min RB size 4 or 8
971 	 * Drop frames that exceed RB size
972 	 * 512 RBDs
973 	 */
974 	iwl_write_prph_no_grab(trans, RFH_RXF_DMA_CFG,
975 			       RFH_DMA_EN_ENABLE_VAL | rb_size |
976 			       RFH_RXF_DMA_MIN_RB_4_8 |
977 			       RFH_RXF_DMA_DROP_TOO_LARGE_MASK |
978 			       RFH_RXF_DMA_RBDCB_SIZE_512);
979 
980 	/*
981 	 * Activate DMA snooping.
982 	 * Set RX DMA chunk size to 64B for IOSF and 128B for PCIe
983 	 * Default queue is 0
984 	 */
985 	iwl_write_prph_no_grab(trans, RFH_GEN_CFG,
986 			       RFH_GEN_CFG_RFH_DMA_SNOOP |
987 			       RFH_GEN_CFG_VAL(DEFAULT_RXQ_NUM, 0) |
988 			       RFH_GEN_CFG_SERVICE_DMA_SNOOP |
989 			       RFH_GEN_CFG_VAL(RB_CHUNK_SIZE,
990 					       trans->trans_cfg->integrated ?
991 					       RFH_GEN_CFG_RB_CHUNK_SIZE_64 :
992 					       RFH_GEN_CFG_RB_CHUNK_SIZE_128));
993 	/* Enable the relevant rx queues */
994 	iwl_write_prph_no_grab(trans, RFH_RXF_RXQ_ACTIVE, enabled);
995 
996 	iwl_trans_release_nic_access(trans);
997 
998 	/* Set interrupt coalescing timer to default (2048 usecs) */
999 	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
1000 }
1001 
1002 void iwl_pcie_rx_init_rxb_lists(struct iwl_rxq *rxq)
1003 {
1004 	lockdep_assert_held(&rxq->lock);
1005 
1006 	INIT_LIST_HEAD(&rxq->rx_free);
1007 	INIT_LIST_HEAD(&rxq->rx_used);
1008 	rxq->free_count = 0;
1009 	rxq->used_count = 0;
1010 }
1011 
1012 static int iwl_pcie_rx_handle(struct iwl_trans *trans, int queue, int budget);
1013 
1014 static int iwl_pcie_napi_poll(struct napi_struct *napi, int budget)
1015 {
1016 	struct iwl_rxq *rxq = container_of(napi, struct iwl_rxq, napi);
1017 	struct iwl_trans_pcie *trans_pcie;
1018 	struct iwl_trans *trans;
1019 	int ret;
1020 
1021 	trans_pcie = container_of(napi->dev, struct iwl_trans_pcie, napi_dev);
1022 	trans = trans_pcie->trans;
1023 
1024 	ret = iwl_pcie_rx_handle(trans, rxq->id, budget);
1025 
1026 	IWL_DEBUG_ISR(trans, "[%d] handled %d, budget %d\n",
1027 		      rxq->id, ret, budget);
1028 
1029 	if (ret < budget) {
1030 		spin_lock(&trans_pcie->irq_lock);
1031 		if (test_bit(STATUS_INT_ENABLED, &trans->status))
1032 			_iwl_enable_interrupts(trans);
1033 		spin_unlock(&trans_pcie->irq_lock);
1034 
1035 		napi_complete_done(&rxq->napi, ret);
1036 	}
1037 
1038 	return ret;
1039 }
1040 
1041 static int iwl_pcie_napi_poll_msix(struct napi_struct *napi, int budget)
1042 {
1043 	struct iwl_rxq *rxq = container_of(napi, struct iwl_rxq, napi);
1044 	struct iwl_trans_pcie *trans_pcie;
1045 	struct iwl_trans *trans;
1046 	int ret;
1047 
1048 	trans_pcie = container_of(napi->dev, struct iwl_trans_pcie, napi_dev);
1049 	trans = trans_pcie->trans;
1050 
1051 	ret = iwl_pcie_rx_handle(trans, rxq->id, budget);
1052 	IWL_DEBUG_ISR(trans, "[%d] handled %d, budget %d\n", rxq->id, ret,
1053 		      budget);
1054 
1055 	if (ret < budget) {
1056 		int irq_line = rxq->id;
1057 
1058 		/* FIRST_RSS is shared with line 0 */
1059 		if (trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS &&
1060 		    rxq->id == 1)
1061 			irq_line = 0;
1062 
1063 		spin_lock(&trans_pcie->irq_lock);
1064 		iwl_pcie_clear_irq(trans, irq_line);
1065 		spin_unlock(&trans_pcie->irq_lock);
1066 
1067 		napi_complete_done(&rxq->napi, ret);
1068 	}
1069 
1070 	return ret;
1071 }
1072 
1073 static int _iwl_pcie_rx_init(struct iwl_trans *trans)
1074 {
1075 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1076 	struct iwl_rxq *def_rxq;
1077 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
1078 	int i, err, queue_size, allocator_pool_size, num_alloc;
1079 
1080 	if (!trans_pcie->rxq) {
1081 		err = iwl_pcie_rx_alloc(trans);
1082 		if (err)
1083 			return err;
1084 	}
1085 	def_rxq = trans_pcie->rxq;
1086 
1087 	cancel_work_sync(&rba->rx_alloc);
1088 
1089 	spin_lock_bh(&rba->lock);
1090 	atomic_set(&rba->req_pending, 0);
1091 	atomic_set(&rba->req_ready, 0);
1092 	INIT_LIST_HEAD(&rba->rbd_allocated);
1093 	INIT_LIST_HEAD(&rba->rbd_empty);
1094 	spin_unlock_bh(&rba->lock);
1095 
1096 	/* free all first - we might be reconfigured for a different size */
1097 	iwl_pcie_free_rbs_pool(trans);
1098 
1099 	for (i = 0; i < RX_QUEUE_SIZE; i++)
1100 		def_rxq->queue[i] = NULL;
1101 
1102 	for (i = 0; i < trans->num_rx_queues; i++) {
1103 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
1104 
1105 		spin_lock_bh(&rxq->lock);
1106 		/*
1107 		 * Set read write pointer to reflect that we have processed
1108 		 * and used all buffers, but have not restocked the Rx queue
1109 		 * with fresh buffers
1110 		 */
1111 		rxq->read = 0;
1112 		rxq->write = 0;
1113 		rxq->write_actual = 0;
1114 		memset(rxq->rb_stts, 0,
1115 		       (trans->trans_cfg->device_family >=
1116 			IWL_DEVICE_FAMILY_AX210) ?
1117 		       sizeof(__le16) : sizeof(struct iwl_rb_status));
1118 
1119 		iwl_pcie_rx_init_rxb_lists(rxq);
1120 
1121 		spin_unlock_bh(&rxq->lock);
1122 
1123 		if (!rxq->napi.poll) {
1124 			int (*poll)(struct napi_struct *, int) = iwl_pcie_napi_poll;
1125 
1126 			if (trans_pcie->msix_enabled)
1127 				poll = iwl_pcie_napi_poll_msix;
1128 
1129 			netif_napi_add(&trans_pcie->napi_dev, &rxq->napi,
1130 				       poll, NAPI_POLL_WEIGHT);
1131 			napi_enable(&rxq->napi);
1132 		}
1133 
1134 	}
1135 
1136 	/* move the pool to the default queue and allocator ownerships */
1137 	queue_size = trans->trans_cfg->mq_rx_supported ?
1138 			trans_pcie->num_rx_bufs - 1 : RX_QUEUE_SIZE;
1139 	allocator_pool_size = trans->num_rx_queues *
1140 		(RX_CLAIM_REQ_ALLOC - RX_POST_REQ_ALLOC);
1141 	num_alloc = queue_size + allocator_pool_size;
1142 
1143 	for (i = 0; i < num_alloc; i++) {
1144 		struct iwl_rx_mem_buffer *rxb = &trans_pcie->rx_pool[i];
1145 
1146 		if (i < allocator_pool_size)
1147 			list_add(&rxb->list, &rba->rbd_empty);
1148 		else
1149 			list_add(&rxb->list, &def_rxq->rx_used);
1150 		trans_pcie->global_table[i] = rxb;
1151 		rxb->vid = (u16)(i + 1);
1152 		rxb->invalid = true;
1153 	}
1154 
1155 	iwl_pcie_rxq_alloc_rbs(trans, GFP_KERNEL, def_rxq);
1156 
1157 	return 0;
1158 }
1159 
1160 int iwl_pcie_rx_init(struct iwl_trans *trans)
1161 {
1162 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1163 	int ret = _iwl_pcie_rx_init(trans);
1164 
1165 	if (ret)
1166 		return ret;
1167 
1168 	if (trans->trans_cfg->mq_rx_supported)
1169 		iwl_pcie_rx_mq_hw_init(trans);
1170 	else
1171 		iwl_pcie_rx_hw_init(trans, trans_pcie->rxq);
1172 
1173 	iwl_pcie_rxq_restock(trans, trans_pcie->rxq);
1174 
1175 	spin_lock_bh(&trans_pcie->rxq->lock);
1176 	iwl_pcie_rxq_inc_wr_ptr(trans, trans_pcie->rxq);
1177 	spin_unlock_bh(&trans_pcie->rxq->lock);
1178 
1179 	return 0;
1180 }
1181 
1182 int iwl_pcie_gen2_rx_init(struct iwl_trans *trans)
1183 {
1184 	/* Set interrupt coalescing timer to default (2048 usecs) */
1185 	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
1186 
1187 	/*
1188 	 * We don't configure the RFH.
1189 	 * Restock will be done at alive, after firmware configured the RFH.
1190 	 */
1191 	return _iwl_pcie_rx_init(trans);
1192 }
1193 
1194 void iwl_pcie_rx_free(struct iwl_trans *trans)
1195 {
1196 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1197 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
1198 	int i;
1199 	size_t rb_stts_size = trans->trans_cfg->device_family >=
1200 				IWL_DEVICE_FAMILY_AX210 ?
1201 			      sizeof(__le16) : sizeof(struct iwl_rb_status);
1202 
1203 	/*
1204 	 * if rxq is NULL, it means that nothing has been allocated,
1205 	 * exit now
1206 	 */
1207 	if (!trans_pcie->rxq) {
1208 		IWL_DEBUG_INFO(trans, "Free NULL rx context\n");
1209 		return;
1210 	}
1211 
1212 	cancel_work_sync(&rba->rx_alloc);
1213 
1214 	iwl_pcie_free_rbs_pool(trans);
1215 
1216 	if (trans_pcie->base_rb_stts) {
1217 		dma_free_coherent(trans->dev,
1218 				  rb_stts_size * trans->num_rx_queues,
1219 				  trans_pcie->base_rb_stts,
1220 				  trans_pcie->base_rb_stts_dma);
1221 		trans_pcie->base_rb_stts = NULL;
1222 		trans_pcie->base_rb_stts_dma = 0;
1223 	}
1224 
1225 	for (i = 0; i < trans->num_rx_queues; i++) {
1226 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
1227 
1228 		iwl_pcie_free_rxq_dma(trans, rxq);
1229 
1230 		if (rxq->napi.poll) {
1231 			napi_disable(&rxq->napi);
1232 			netif_napi_del(&rxq->napi);
1233 		}
1234 	}
1235 	kfree(trans_pcie->rx_pool);
1236 	kfree(trans_pcie->global_table);
1237 	kfree(trans_pcie->rxq);
1238 
1239 	if (trans_pcie->alloc_page)
1240 		__free_pages(trans_pcie->alloc_page, trans_pcie->rx_page_order);
1241 }
1242 
1243 static void iwl_pcie_rx_move_to_allocator(struct iwl_rxq *rxq,
1244 					  struct iwl_rb_allocator *rba)
1245 {
1246 	spin_lock(&rba->lock);
1247 	list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty);
1248 	spin_unlock(&rba->lock);
1249 }
1250 
1251 /*
1252  * iwl_pcie_rx_reuse_rbd - Recycle used RBDs
1253  *
1254  * Called when a RBD can be reused. The RBD is transferred to the allocator.
1255  * When there are 2 empty RBDs - a request for allocation is posted
1256  */
1257 static void iwl_pcie_rx_reuse_rbd(struct iwl_trans *trans,
1258 				  struct iwl_rx_mem_buffer *rxb,
1259 				  struct iwl_rxq *rxq, bool emergency)
1260 {
1261 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1262 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
1263 
1264 	/* Move the RBD to the used list, will be moved to allocator in batches
1265 	 * before claiming or posting a request*/
1266 	list_add_tail(&rxb->list, &rxq->rx_used);
1267 
1268 	if (unlikely(emergency))
1269 		return;
1270 
1271 	/* Count the allocator owned RBDs */
1272 	rxq->used_count++;
1273 
1274 	/* If we have RX_POST_REQ_ALLOC new released rx buffers -
1275 	 * issue a request for allocator. Modulo RX_CLAIM_REQ_ALLOC is
1276 	 * used for the case we failed to claim RX_CLAIM_REQ_ALLOC,
1277 	 * after but we still need to post another request.
1278 	 */
1279 	if ((rxq->used_count % RX_CLAIM_REQ_ALLOC) == RX_POST_REQ_ALLOC) {
1280 		/* Move the 2 RBDs to the allocator ownership.
1281 		 Allocator has another 6 from pool for the request completion*/
1282 		iwl_pcie_rx_move_to_allocator(rxq, rba);
1283 
1284 		atomic_inc(&rba->req_pending);
1285 		queue_work(rba->alloc_wq, &rba->rx_alloc);
1286 	}
1287 }
1288 
1289 static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
1290 				struct iwl_rxq *rxq,
1291 				struct iwl_rx_mem_buffer *rxb,
1292 				bool emergency,
1293 				int i)
1294 {
1295 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1296 	struct iwl_txq *txq = trans->txqs.txq[trans->txqs.cmd.q_id];
1297 	bool page_stolen = false;
1298 	int max_len = trans_pcie->rx_buf_bytes;
1299 	u32 offset = 0;
1300 
1301 	if (WARN_ON(!rxb))
1302 		return;
1303 
1304 	dma_unmap_page(trans->dev, rxb->page_dma, max_len, DMA_FROM_DEVICE);
1305 
1306 	while (offset + sizeof(u32) + sizeof(struct iwl_cmd_header) < max_len) {
1307 		struct iwl_rx_packet *pkt;
1308 		bool reclaim;
1309 		int len;
1310 		struct iwl_rx_cmd_buffer rxcb = {
1311 			._offset = rxb->offset + offset,
1312 			._rx_page_order = trans_pcie->rx_page_order,
1313 			._page = rxb->page,
1314 			._page_stolen = false,
1315 			.truesize = max_len,
1316 		};
1317 
1318 		pkt = rxb_addr(&rxcb);
1319 
1320 		if (pkt->len_n_flags == cpu_to_le32(FH_RSCSR_FRAME_INVALID)) {
1321 			IWL_DEBUG_RX(trans,
1322 				     "Q %d: RB end marker at offset %d\n",
1323 				     rxq->id, offset);
1324 			break;
1325 		}
1326 
1327 		WARN((le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_RXQ_MASK) >>
1328 			FH_RSCSR_RXQ_POS != rxq->id,
1329 		     "frame on invalid queue - is on %d and indicates %d\n",
1330 		     rxq->id,
1331 		     (le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_RXQ_MASK) >>
1332 			FH_RSCSR_RXQ_POS);
1333 
1334 		IWL_DEBUG_RX(trans,
1335 			     "Q %d: cmd at offset %d: %s (%.2x.%2x, seq 0x%x)\n",
1336 			     rxq->id, offset,
1337 			     iwl_get_cmd_string(trans,
1338 						iwl_cmd_id(pkt->hdr.cmd,
1339 							   pkt->hdr.group_id,
1340 							   0)),
1341 			     pkt->hdr.group_id, pkt->hdr.cmd,
1342 			     le16_to_cpu(pkt->hdr.sequence));
1343 
1344 		len = iwl_rx_packet_len(pkt);
1345 		len += sizeof(u32); /* account for status word */
1346 
1347 		offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
1348 
1349 		/* check that what the device tells us made sense */
1350 		if (offset > max_len)
1351 			break;
1352 
1353 		trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len);
1354 		trace_iwlwifi_dev_rx_data(trans->dev, trans, pkt, len);
1355 
1356 		/* Reclaim a command buffer only if this packet is a response
1357 		 *   to a (driver-originated) command.
1358 		 * If the packet (e.g. Rx frame) originated from uCode,
1359 		 *   there is no command buffer to reclaim.
1360 		 * Ucode should set SEQ_RX_FRAME bit if ucode-originated,
1361 		 *   but apparently a few don't get set; catch them here. */
1362 		reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME);
1363 		if (reclaim && !pkt->hdr.group_id) {
1364 			int i;
1365 
1366 			for (i = 0; i < trans_pcie->n_no_reclaim_cmds; i++) {
1367 				if (trans_pcie->no_reclaim_cmds[i] ==
1368 							pkt->hdr.cmd) {
1369 					reclaim = false;
1370 					break;
1371 				}
1372 			}
1373 		}
1374 
1375 		if (rxq->id == trans_pcie->def_rx_queue)
1376 			iwl_op_mode_rx(trans->op_mode, &rxq->napi,
1377 				       &rxcb);
1378 		else
1379 			iwl_op_mode_rx_rss(trans->op_mode, &rxq->napi,
1380 					   &rxcb, rxq->id);
1381 
1382 		/*
1383 		 * After here, we should always check rxcb._page_stolen,
1384 		 * if it is true then one of the handlers took the page.
1385 		 */
1386 
1387 		if (reclaim) {
1388 			u16 sequence = le16_to_cpu(pkt->hdr.sequence);
1389 			int index = SEQ_TO_INDEX(sequence);
1390 			int cmd_index = iwl_txq_get_cmd_index(txq, index);
1391 
1392 			kfree_sensitive(txq->entries[cmd_index].free_buf);
1393 			txq->entries[cmd_index].free_buf = NULL;
1394 
1395 			/* Invoke any callbacks, transfer the buffer to caller,
1396 			 * and fire off the (possibly) blocking
1397 			 * iwl_trans_send_cmd()
1398 			 * as we reclaim the driver command queue */
1399 			if (!rxcb._page_stolen)
1400 				iwl_pcie_hcmd_complete(trans, &rxcb);
1401 			else
1402 				IWL_WARN(trans, "Claim null rxb?\n");
1403 		}
1404 
1405 		page_stolen |= rxcb._page_stolen;
1406 		if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
1407 			break;
1408 	}
1409 
1410 	/* page was stolen from us -- free our reference */
1411 	if (page_stolen) {
1412 		__free_pages(rxb->page, trans_pcie->rx_page_order);
1413 		rxb->page = NULL;
1414 	}
1415 
1416 	/* Reuse the page if possible. For notification packets and
1417 	 * SKBs that fail to Rx correctly, add them back into the
1418 	 * rx_free list for reuse later. */
1419 	if (rxb->page != NULL) {
1420 		rxb->page_dma =
1421 			dma_map_page(trans->dev, rxb->page, rxb->offset,
1422 				     trans_pcie->rx_buf_bytes,
1423 				     DMA_FROM_DEVICE);
1424 		if (dma_mapping_error(trans->dev, rxb->page_dma)) {
1425 			/*
1426 			 * free the page(s) as well to not break
1427 			 * the invariant that the items on the used
1428 			 * list have no page(s)
1429 			 */
1430 			__free_pages(rxb->page, trans_pcie->rx_page_order);
1431 			rxb->page = NULL;
1432 			iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
1433 		} else {
1434 			list_add_tail(&rxb->list, &rxq->rx_free);
1435 			rxq->free_count++;
1436 		}
1437 	} else
1438 		iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
1439 }
1440 
1441 static struct iwl_rx_mem_buffer *iwl_pcie_get_rxb(struct iwl_trans *trans,
1442 						  struct iwl_rxq *rxq, int i,
1443 						  bool *join)
1444 {
1445 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1446 	struct iwl_rx_mem_buffer *rxb;
1447 	u16 vid;
1448 
1449 	BUILD_BUG_ON(sizeof(struct iwl_rx_completion_desc) != 32);
1450 
1451 	if (!trans->trans_cfg->mq_rx_supported) {
1452 		rxb = rxq->queue[i];
1453 		rxq->queue[i] = NULL;
1454 		return rxb;
1455 	}
1456 
1457 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {
1458 		vid = le16_to_cpu(rxq->cd[i].rbid);
1459 		*join = rxq->cd[i].flags & IWL_RX_CD_FLAGS_FRAGMENTED;
1460 	} else {
1461 		vid = le32_to_cpu(rxq->bd_32[i]) & 0x0FFF; /* 12-bit VID */
1462 	}
1463 
1464 	if (!vid || vid > RX_POOL_SIZE(trans_pcie->num_rx_bufs))
1465 		goto out_err;
1466 
1467 	rxb = trans_pcie->global_table[vid - 1];
1468 	if (rxb->invalid)
1469 		goto out_err;
1470 
1471 	IWL_DEBUG_RX(trans, "Got virtual RB ID %u\n", (u32)rxb->vid);
1472 
1473 	rxb->invalid = true;
1474 
1475 	return rxb;
1476 
1477 out_err:
1478 	WARN(1, "Invalid rxb from HW %u\n", (u32)vid);
1479 	iwl_force_nmi(trans);
1480 	return NULL;
1481 }
1482 
1483 /*
1484  * iwl_pcie_rx_handle - Main entry function for receiving responses from fw
1485  */
1486 static int iwl_pcie_rx_handle(struct iwl_trans *trans, int queue, int budget)
1487 {
1488 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1489 	struct iwl_rxq *rxq;
1490 	u32 r, i, count = 0, handled = 0;
1491 	bool emergency = false;
1492 
1493 	if (WARN_ON_ONCE(!trans_pcie->rxq || !trans_pcie->rxq[queue].bd))
1494 		return budget;
1495 
1496 	rxq = &trans_pcie->rxq[queue];
1497 
1498 restart:
1499 	spin_lock(&rxq->lock);
1500 	/* uCode's read index (stored in shared DRAM) indicates the last Rx
1501 	 * buffer that the driver may process (last buffer filled by ucode). */
1502 	r = le16_to_cpu(iwl_get_closed_rb_stts(trans, rxq)) & 0x0FFF;
1503 	i = rxq->read;
1504 
1505 	/* W/A 9000 device step A0 wrap-around bug */
1506 	r &= (rxq->queue_size - 1);
1507 
1508 	/* Rx interrupt, but nothing sent from uCode */
1509 	if (i == r)
1510 		IWL_DEBUG_RX(trans, "Q %d: HW = SW = %d\n", rxq->id, r);
1511 
1512 	while (i != r && ++handled < budget) {
1513 		struct iwl_rb_allocator *rba = &trans_pcie->rba;
1514 		struct iwl_rx_mem_buffer *rxb;
1515 		/* number of RBDs still waiting for page allocation */
1516 		u32 rb_pending_alloc =
1517 			atomic_read(&trans_pcie->rba.req_pending) *
1518 			RX_CLAIM_REQ_ALLOC;
1519 		bool join = false;
1520 
1521 		if (unlikely(rb_pending_alloc >= rxq->queue_size / 2 &&
1522 			     !emergency)) {
1523 			iwl_pcie_rx_move_to_allocator(rxq, rba);
1524 			emergency = true;
1525 			IWL_DEBUG_TPT(trans,
1526 				      "RX path is in emergency. Pending allocations %d\n",
1527 				      rb_pending_alloc);
1528 		}
1529 
1530 		IWL_DEBUG_RX(trans, "Q %d: HW = %d, SW = %d\n", rxq->id, r, i);
1531 
1532 		rxb = iwl_pcie_get_rxb(trans, rxq, i, &join);
1533 		if (!rxb)
1534 			goto out;
1535 
1536 		if (unlikely(join || rxq->next_rb_is_fragment)) {
1537 			rxq->next_rb_is_fragment = join;
1538 			/*
1539 			 * We can only get a multi-RB in the following cases:
1540 			 *  - firmware issue, sending a too big notification
1541 			 *  - sniffer mode with a large A-MSDU
1542 			 *  - large MTU frames (>2k)
1543 			 * since the multi-RB functionality is limited to newer
1544 			 * hardware that cannot put multiple entries into a
1545 			 * single RB.
1546 			 *
1547 			 * Right now, the higher layers aren't set up to deal
1548 			 * with that, so discard all of these.
1549 			 */
1550 			list_add_tail(&rxb->list, &rxq->rx_free);
1551 			rxq->free_count++;
1552 		} else {
1553 			iwl_pcie_rx_handle_rb(trans, rxq, rxb, emergency, i);
1554 		}
1555 
1556 		i = (i + 1) & (rxq->queue_size - 1);
1557 
1558 		/*
1559 		 * If we have RX_CLAIM_REQ_ALLOC released rx buffers -
1560 		 * try to claim the pre-allocated buffers from the allocator.
1561 		 * If not ready - will try to reclaim next time.
1562 		 * There is no need to reschedule work - allocator exits only
1563 		 * on success
1564 		 */
1565 		if (rxq->used_count >= RX_CLAIM_REQ_ALLOC)
1566 			iwl_pcie_rx_allocator_get(trans, rxq);
1567 
1568 		if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 && !emergency) {
1569 			/* Add the remaining empty RBDs for allocator use */
1570 			iwl_pcie_rx_move_to_allocator(rxq, rba);
1571 		} else if (emergency) {
1572 			count++;
1573 			if (count == 8) {
1574 				count = 0;
1575 				if (rb_pending_alloc < rxq->queue_size / 3) {
1576 					IWL_DEBUG_TPT(trans,
1577 						      "RX path exited emergency. Pending allocations %d\n",
1578 						      rb_pending_alloc);
1579 					emergency = false;
1580 				}
1581 
1582 				rxq->read = i;
1583 				spin_unlock(&rxq->lock);
1584 				iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
1585 				iwl_pcie_rxq_restock(trans, rxq);
1586 				goto restart;
1587 			}
1588 		}
1589 	}
1590 out:
1591 	/* Backtrack one entry */
1592 	rxq->read = i;
1593 	/* update cr tail with the rxq read pointer */
1594 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
1595 		*rxq->cr_tail = cpu_to_le16(r);
1596 	spin_unlock(&rxq->lock);
1597 
1598 	/*
1599 	 * handle a case where in emergency there are some unallocated RBDs.
1600 	 * those RBDs are in the used list, but are not tracked by the queue's
1601 	 * used_count which counts allocator owned RBDs.
1602 	 * unallocated emergency RBDs must be allocated on exit, otherwise
1603 	 * when called again the function may not be in emergency mode and
1604 	 * they will be handed to the allocator with no tracking in the RBD
1605 	 * allocator counters, which will lead to them never being claimed back
1606 	 * by the queue.
1607 	 * by allocating them here, they are now in the queue free list, and
1608 	 * will be restocked by the next call of iwl_pcie_rxq_restock.
1609 	 */
1610 	if (unlikely(emergency && count))
1611 		iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
1612 
1613 	iwl_pcie_rxq_restock(trans, rxq);
1614 
1615 	return handled;
1616 }
1617 
1618 static struct iwl_trans_pcie *iwl_pcie_get_trans_pcie(struct msix_entry *entry)
1619 {
1620 	u8 queue = entry->entry;
1621 	struct msix_entry *entries = entry - queue;
1622 
1623 	return container_of(entries, struct iwl_trans_pcie, msix_entries[0]);
1624 }
1625 
1626 /*
1627  * iwl_pcie_rx_msix_handle - Main entry function for receiving responses from fw
1628  * This interrupt handler should be used with RSS queue only.
1629  */
1630 irqreturn_t iwl_pcie_irq_rx_msix_handler(int irq, void *dev_id)
1631 {
1632 	struct msix_entry *entry = dev_id;
1633 	struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
1634 	struct iwl_trans *trans = trans_pcie->trans;
1635 	struct iwl_rxq *rxq = &trans_pcie->rxq[entry->entry];
1636 
1637 	trace_iwlwifi_dev_irq_msix(trans->dev, entry, false, 0, 0);
1638 
1639 	if (WARN_ON(entry->entry >= trans->num_rx_queues))
1640 		return IRQ_NONE;
1641 
1642 	if (WARN_ONCE(!rxq,
1643 		      "[%d] Got MSI-X interrupt before we have Rx queues",
1644 		      entry->entry))
1645 		return IRQ_NONE;
1646 
1647 	lock_map_acquire(&trans->sync_cmd_lockdep_map);
1648 	IWL_DEBUG_ISR(trans, "[%d] Got interrupt\n", entry->entry);
1649 
1650 	local_bh_disable();
1651 	if (napi_schedule_prep(&rxq->napi))
1652 		__napi_schedule(&rxq->napi);
1653 	else
1654 		iwl_pcie_clear_irq(trans, entry->entry);
1655 	local_bh_enable();
1656 
1657 	lock_map_release(&trans->sync_cmd_lockdep_map);
1658 
1659 	return IRQ_HANDLED;
1660 }
1661 
1662 /*
1663  * iwl_pcie_irq_handle_error - called for HW or SW error interrupt from card
1664  */
1665 static void iwl_pcie_irq_handle_error(struct iwl_trans *trans)
1666 {
1667 	int i;
1668 
1669 	/* W/A for WiFi/WiMAX coex and WiMAX own the RF */
1670 	if (trans->cfg->internal_wimax_coex &&
1671 	    !trans->cfg->apmg_not_supported &&
1672 	    (!(iwl_read_prph(trans, APMG_CLK_CTRL_REG) &
1673 			     APMS_CLK_VAL_MRB_FUNC_MODE) ||
1674 	     (iwl_read_prph(trans, APMG_PS_CTRL_REG) &
1675 			    APMG_PS_CTRL_VAL_RESET_REQ))) {
1676 		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1677 		iwl_op_mode_wimax_active(trans->op_mode);
1678 		wake_up(&trans->wait_command_queue);
1679 		return;
1680 	}
1681 
1682 	for (i = 0; i < trans->trans_cfg->base_params->num_of_queues; i++) {
1683 		if (!trans->txqs.txq[i])
1684 			continue;
1685 		del_timer(&trans->txqs.txq[i]->stuck_timer);
1686 	}
1687 
1688 	/* The STATUS_FW_ERROR bit is set in this function. This must happen
1689 	 * before we wake up the command caller, to ensure a proper cleanup. */
1690 	iwl_trans_fw_error(trans);
1691 
1692 	clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1693 	wake_up(&trans->wait_command_queue);
1694 }
1695 
1696 static u32 iwl_pcie_int_cause_non_ict(struct iwl_trans *trans)
1697 {
1698 	u32 inta;
1699 
1700 	lockdep_assert_held(&IWL_TRANS_GET_PCIE_TRANS(trans)->irq_lock);
1701 
1702 	trace_iwlwifi_dev_irq(trans->dev);
1703 
1704 	/* Discover which interrupts are active/pending */
1705 	inta = iwl_read32(trans, CSR_INT);
1706 
1707 	/* the thread will service interrupts and re-enable them */
1708 	return inta;
1709 }
1710 
1711 /* a device (PCI-E) page is 4096 bytes long */
1712 #define ICT_SHIFT	12
1713 #define ICT_SIZE	(1 << ICT_SHIFT)
1714 #define ICT_COUNT	(ICT_SIZE / sizeof(u32))
1715 
1716 /* interrupt handler using ict table, with this interrupt driver will
1717  * stop using INTA register to get device's interrupt, reading this register
1718  * is expensive, device will write interrupts in ICT dram table, increment
1719  * index then will fire interrupt to driver, driver will OR all ICT table
1720  * entries from current index up to table entry with 0 value. the result is
1721  * the interrupt we need to service, driver will set the entries back to 0 and
1722  * set index.
1723  */
1724 static u32 iwl_pcie_int_cause_ict(struct iwl_trans *trans)
1725 {
1726 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1727 	u32 inta;
1728 	u32 val = 0;
1729 	u32 read;
1730 
1731 	trace_iwlwifi_dev_irq(trans->dev);
1732 
1733 	/* Ignore interrupt if there's nothing in NIC to service.
1734 	 * This may be due to IRQ shared with another device,
1735 	 * or due to sporadic interrupts thrown from our NIC. */
1736 	read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1737 	trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, read);
1738 	if (!read)
1739 		return 0;
1740 
1741 	/*
1742 	 * Collect all entries up to the first 0, starting from ict_index;
1743 	 * note we already read at ict_index.
1744 	 */
1745 	do {
1746 		val |= read;
1747 		IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n",
1748 				trans_pcie->ict_index, read);
1749 		trans_pcie->ict_tbl[trans_pcie->ict_index] = 0;
1750 		trans_pcie->ict_index =
1751 			((trans_pcie->ict_index + 1) & (ICT_COUNT - 1));
1752 
1753 		read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1754 		trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index,
1755 					   read);
1756 	} while (read);
1757 
1758 	/* We should not get this value, just ignore it. */
1759 	if (val == 0xffffffff)
1760 		val = 0;
1761 
1762 	/*
1763 	 * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit
1764 	 * (bit 15 before shifting it to 31) to clear when using interrupt
1765 	 * coalescing. fortunately, bits 18 and 19 stay set when this happens
1766 	 * so we use them to decide on the real state of the Rx bit.
1767 	 * In order words, bit 15 is set if bit 18 or bit 19 are set.
1768 	 */
1769 	if (val & 0xC0000)
1770 		val |= 0x8000;
1771 
1772 	inta = (0xff & val) | ((0xff00 & val) << 16);
1773 	return inta;
1774 }
1775 
1776 void iwl_pcie_handle_rfkill_irq(struct iwl_trans *trans)
1777 {
1778 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1779 	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1780 	bool hw_rfkill, prev, report;
1781 
1782 	mutex_lock(&trans_pcie->mutex);
1783 	prev = test_bit(STATUS_RFKILL_OPMODE, &trans->status);
1784 	hw_rfkill = iwl_is_rfkill_set(trans);
1785 	if (hw_rfkill) {
1786 		set_bit(STATUS_RFKILL_OPMODE, &trans->status);
1787 		set_bit(STATUS_RFKILL_HW, &trans->status);
1788 	}
1789 	if (trans_pcie->opmode_down)
1790 		report = hw_rfkill;
1791 	else
1792 		report = test_bit(STATUS_RFKILL_OPMODE, &trans->status);
1793 
1794 	IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
1795 		 hw_rfkill ? "disable radio" : "enable radio");
1796 
1797 	isr_stats->rfkill++;
1798 
1799 	if (prev != report)
1800 		iwl_trans_pcie_rf_kill(trans, report);
1801 	mutex_unlock(&trans_pcie->mutex);
1802 
1803 	if (hw_rfkill) {
1804 		if (test_and_clear_bit(STATUS_SYNC_HCMD_ACTIVE,
1805 				       &trans->status))
1806 			IWL_DEBUG_RF_KILL(trans,
1807 					  "Rfkill while SYNC HCMD in flight\n");
1808 		wake_up(&trans->wait_command_queue);
1809 	} else {
1810 		clear_bit(STATUS_RFKILL_HW, &trans->status);
1811 		if (trans_pcie->opmode_down)
1812 			clear_bit(STATUS_RFKILL_OPMODE, &trans->status);
1813 	}
1814 }
1815 
1816 irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id)
1817 {
1818 	struct iwl_trans *trans = dev_id;
1819 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1820 	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1821 	u32 inta = 0;
1822 	u32 handled = 0;
1823 	bool polling = false;
1824 
1825 	lock_map_acquire(&trans->sync_cmd_lockdep_map);
1826 
1827 	spin_lock_bh(&trans_pcie->irq_lock);
1828 
1829 	/* dram interrupt table not set yet,
1830 	 * use legacy interrupt.
1831 	 */
1832 	if (likely(trans_pcie->use_ict))
1833 		inta = iwl_pcie_int_cause_ict(trans);
1834 	else
1835 		inta = iwl_pcie_int_cause_non_ict(trans);
1836 
1837 	if (iwl_have_debug_level(IWL_DL_ISR)) {
1838 		IWL_DEBUG_ISR(trans,
1839 			      "ISR inta 0x%08x, enabled 0x%08x(sw), enabled(hw) 0x%08x, fh 0x%08x\n",
1840 			      inta, trans_pcie->inta_mask,
1841 			      iwl_read32(trans, CSR_INT_MASK),
1842 			      iwl_read32(trans, CSR_FH_INT_STATUS));
1843 		if (inta & (~trans_pcie->inta_mask))
1844 			IWL_DEBUG_ISR(trans,
1845 				      "We got a masked interrupt (0x%08x)\n",
1846 				      inta & (~trans_pcie->inta_mask));
1847 	}
1848 
1849 	inta &= trans_pcie->inta_mask;
1850 
1851 	/*
1852 	 * Ignore interrupt if there's nothing in NIC to service.
1853 	 * This may be due to IRQ shared with another device,
1854 	 * or due to sporadic interrupts thrown from our NIC.
1855 	 */
1856 	if (unlikely(!inta)) {
1857 		IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1858 		/*
1859 		 * Re-enable interrupts here since we don't
1860 		 * have anything to service
1861 		 */
1862 		if (test_bit(STATUS_INT_ENABLED, &trans->status))
1863 			_iwl_enable_interrupts(trans);
1864 		spin_unlock_bh(&trans_pcie->irq_lock);
1865 		lock_map_release(&trans->sync_cmd_lockdep_map);
1866 		return IRQ_NONE;
1867 	}
1868 
1869 	if (unlikely(inta == 0xFFFFFFFF || (inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
1870 		/*
1871 		 * Hardware disappeared. It might have
1872 		 * already raised an interrupt.
1873 		 */
1874 		IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta);
1875 		spin_unlock_bh(&trans_pcie->irq_lock);
1876 		goto out;
1877 	}
1878 
1879 	/* Ack/clear/reset pending uCode interrupts.
1880 	 * Note:  Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS,
1881 	 */
1882 	/* There is a hardware bug in the interrupt mask function that some
1883 	 * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if
1884 	 * they are disabled in the CSR_INT_MASK register. Furthermore the
1885 	 * ICT interrupt handling mechanism has another bug that might cause
1886 	 * these unmasked interrupts fail to be detected. We workaround the
1887 	 * hardware bugs here by ACKing all the possible interrupts so that
1888 	 * interrupt coalescing can still be achieved.
1889 	 */
1890 	iwl_write32(trans, CSR_INT, inta | ~trans_pcie->inta_mask);
1891 
1892 	if (iwl_have_debug_level(IWL_DL_ISR))
1893 		IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n",
1894 			      inta, iwl_read32(trans, CSR_INT_MASK));
1895 
1896 	spin_unlock_bh(&trans_pcie->irq_lock);
1897 
1898 	/* Now service all interrupt bits discovered above. */
1899 	if (inta & CSR_INT_BIT_HW_ERR) {
1900 		IWL_ERR(trans, "Hardware error detected.  Restarting.\n");
1901 
1902 		/* Tell the device to stop sending interrupts */
1903 		iwl_disable_interrupts(trans);
1904 
1905 		isr_stats->hw++;
1906 		iwl_pcie_irq_handle_error(trans);
1907 
1908 		handled |= CSR_INT_BIT_HW_ERR;
1909 
1910 		goto out;
1911 	}
1912 
1913 	/* NIC fires this, but we don't use it, redundant with WAKEUP */
1914 	if (inta & CSR_INT_BIT_SCD) {
1915 		IWL_DEBUG_ISR(trans,
1916 			      "Scheduler finished to transmit the frame/frames.\n");
1917 		isr_stats->sch++;
1918 	}
1919 
1920 	/* Alive notification via Rx interrupt will do the real work */
1921 	if (inta & CSR_INT_BIT_ALIVE) {
1922 		IWL_DEBUG_ISR(trans, "Alive interrupt\n");
1923 		isr_stats->alive++;
1924 		if (trans->trans_cfg->gen2) {
1925 			/*
1926 			 * We can restock, since firmware configured
1927 			 * the RFH
1928 			 */
1929 			iwl_pcie_rxmq_restock(trans, trans_pcie->rxq);
1930 		}
1931 
1932 		handled |= CSR_INT_BIT_ALIVE;
1933 	}
1934 
1935 	/* Safely ignore these bits for debug checks below */
1936 	inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE);
1937 
1938 	/* HW RF KILL switch toggled */
1939 	if (inta & CSR_INT_BIT_RF_KILL) {
1940 		iwl_pcie_handle_rfkill_irq(trans);
1941 		handled |= CSR_INT_BIT_RF_KILL;
1942 	}
1943 
1944 	/* Chip got too hot and stopped itself */
1945 	if (inta & CSR_INT_BIT_CT_KILL) {
1946 		IWL_ERR(trans, "Microcode CT kill error detected.\n");
1947 		isr_stats->ctkill++;
1948 		handled |= CSR_INT_BIT_CT_KILL;
1949 	}
1950 
1951 	/* Error detected by uCode */
1952 	if (inta & CSR_INT_BIT_SW_ERR) {
1953 		IWL_ERR(trans, "Microcode SW error detected. "
1954 			" Restarting 0x%X.\n", inta);
1955 		isr_stats->sw++;
1956 		iwl_pcie_irq_handle_error(trans);
1957 		handled |= CSR_INT_BIT_SW_ERR;
1958 	}
1959 
1960 	/* uCode wakes up after power-down sleep */
1961 	if (inta & CSR_INT_BIT_WAKEUP) {
1962 		IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
1963 		iwl_pcie_rxq_check_wrptr(trans);
1964 		iwl_pcie_txq_check_wrptrs(trans);
1965 
1966 		isr_stats->wakeup++;
1967 
1968 		handled |= CSR_INT_BIT_WAKEUP;
1969 	}
1970 
1971 	/* All uCode command responses, including Tx command responses,
1972 	 * Rx "responses" (frame-received notification), and other
1973 	 * notifications from uCode come through here*/
1974 	if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX |
1975 		    CSR_INT_BIT_RX_PERIODIC)) {
1976 		IWL_DEBUG_ISR(trans, "Rx interrupt\n");
1977 		if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) {
1978 			handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX);
1979 			iwl_write32(trans, CSR_FH_INT_STATUS,
1980 					CSR_FH_INT_RX_MASK);
1981 		}
1982 		if (inta & CSR_INT_BIT_RX_PERIODIC) {
1983 			handled |= CSR_INT_BIT_RX_PERIODIC;
1984 			iwl_write32(trans,
1985 				CSR_INT, CSR_INT_BIT_RX_PERIODIC);
1986 		}
1987 		/* Sending RX interrupt require many steps to be done in the
1988 		 * the device:
1989 		 * 1- write interrupt to current index in ICT table.
1990 		 * 2- dma RX frame.
1991 		 * 3- update RX shared data to indicate last write index.
1992 		 * 4- send interrupt.
1993 		 * This could lead to RX race, driver could receive RX interrupt
1994 		 * but the shared data changes does not reflect this;
1995 		 * periodic interrupt will detect any dangling Rx activity.
1996 		 */
1997 
1998 		/* Disable periodic interrupt; we use it as just a one-shot. */
1999 		iwl_write8(trans, CSR_INT_PERIODIC_REG,
2000 			    CSR_INT_PERIODIC_DIS);
2001 
2002 		/*
2003 		 * Enable periodic interrupt in 8 msec only if we received
2004 		 * real RX interrupt (instead of just periodic int), to catch
2005 		 * any dangling Rx interrupt.  If it was just the periodic
2006 		 * interrupt, there was no dangling Rx activity, and no need
2007 		 * to extend the periodic interrupt; one-shot is enough.
2008 		 */
2009 		if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX))
2010 			iwl_write8(trans, CSR_INT_PERIODIC_REG,
2011 				   CSR_INT_PERIODIC_ENA);
2012 
2013 		isr_stats->rx++;
2014 
2015 		local_bh_disable();
2016 		if (napi_schedule_prep(&trans_pcie->rxq[0].napi)) {
2017 			polling = true;
2018 			__napi_schedule(&trans_pcie->rxq[0].napi);
2019 		}
2020 		local_bh_enable();
2021 	}
2022 
2023 	/* This "Tx" DMA channel is used only for loading uCode */
2024 	if (inta & CSR_INT_BIT_FH_TX) {
2025 		iwl_write32(trans, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
2026 		IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
2027 		isr_stats->tx++;
2028 		handled |= CSR_INT_BIT_FH_TX;
2029 		/* Wake up uCode load routine, now that load is complete */
2030 		trans_pcie->ucode_write_complete = true;
2031 		wake_up(&trans_pcie->ucode_write_waitq);
2032 	}
2033 
2034 	if (inta & ~handled) {
2035 		IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
2036 		isr_stats->unhandled++;
2037 	}
2038 
2039 	if (inta & ~(trans_pcie->inta_mask)) {
2040 		IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n",
2041 			 inta & ~trans_pcie->inta_mask);
2042 	}
2043 
2044 	if (!polling) {
2045 		spin_lock_bh(&trans_pcie->irq_lock);
2046 		/* only Re-enable all interrupt if disabled by irq */
2047 		if (test_bit(STATUS_INT_ENABLED, &trans->status))
2048 			_iwl_enable_interrupts(trans);
2049 		/* we are loading the firmware, enable FH_TX interrupt only */
2050 		else if (handled & CSR_INT_BIT_FH_TX)
2051 			iwl_enable_fw_load_int(trans);
2052 		/* Re-enable RF_KILL if it occurred */
2053 		else if (handled & CSR_INT_BIT_RF_KILL)
2054 			iwl_enable_rfkill_int(trans);
2055 		/* Re-enable the ALIVE / Rx interrupt if it occurred */
2056 		else if (handled & (CSR_INT_BIT_ALIVE | CSR_INT_BIT_FH_RX))
2057 			iwl_enable_fw_load_int_ctx_info(trans);
2058 		spin_unlock_bh(&trans_pcie->irq_lock);
2059 	}
2060 
2061 out:
2062 	lock_map_release(&trans->sync_cmd_lockdep_map);
2063 	return IRQ_HANDLED;
2064 }
2065 
2066 /******************************************************************************
2067  *
2068  * ICT functions
2069  *
2070  ******************************************************************************/
2071 
2072 /* Free dram table */
2073 void iwl_pcie_free_ict(struct iwl_trans *trans)
2074 {
2075 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2076 
2077 	if (trans_pcie->ict_tbl) {
2078 		dma_free_coherent(trans->dev, ICT_SIZE,
2079 				  trans_pcie->ict_tbl,
2080 				  trans_pcie->ict_tbl_dma);
2081 		trans_pcie->ict_tbl = NULL;
2082 		trans_pcie->ict_tbl_dma = 0;
2083 	}
2084 }
2085 
2086 /*
2087  * allocate dram shared table, it is an aligned memory
2088  * block of ICT_SIZE.
2089  * also reset all data related to ICT table interrupt.
2090  */
2091 int iwl_pcie_alloc_ict(struct iwl_trans *trans)
2092 {
2093 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2094 
2095 	trans_pcie->ict_tbl =
2096 		dma_alloc_coherent(trans->dev, ICT_SIZE,
2097 				   &trans_pcie->ict_tbl_dma, GFP_KERNEL);
2098 	if (!trans_pcie->ict_tbl)
2099 		return -ENOMEM;
2100 
2101 	/* just an API sanity check ... it is guaranteed to be aligned */
2102 	if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) {
2103 		iwl_pcie_free_ict(trans);
2104 		return -EINVAL;
2105 	}
2106 
2107 	return 0;
2108 }
2109 
2110 /* Device is going up inform it about using ICT interrupt table,
2111  * also we need to tell the driver to start using ICT interrupt.
2112  */
2113 void iwl_pcie_reset_ict(struct iwl_trans *trans)
2114 {
2115 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2116 	u32 val;
2117 
2118 	if (!trans_pcie->ict_tbl)
2119 		return;
2120 
2121 	spin_lock_bh(&trans_pcie->irq_lock);
2122 	_iwl_disable_interrupts(trans);
2123 
2124 	memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
2125 
2126 	val = trans_pcie->ict_tbl_dma >> ICT_SHIFT;
2127 
2128 	val |= CSR_DRAM_INT_TBL_ENABLE |
2129 	       CSR_DRAM_INIT_TBL_WRAP_CHECK |
2130 	       CSR_DRAM_INIT_TBL_WRITE_POINTER;
2131 
2132 	IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val);
2133 
2134 	iwl_write32(trans, CSR_DRAM_INT_TBL_REG, val);
2135 	trans_pcie->use_ict = true;
2136 	trans_pcie->ict_index = 0;
2137 	iwl_write32(trans, CSR_INT, trans_pcie->inta_mask);
2138 	_iwl_enable_interrupts(trans);
2139 	spin_unlock_bh(&trans_pcie->irq_lock);
2140 }
2141 
2142 /* Device is going down disable ict interrupt usage */
2143 void iwl_pcie_disable_ict(struct iwl_trans *trans)
2144 {
2145 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2146 
2147 	spin_lock_bh(&trans_pcie->irq_lock);
2148 	trans_pcie->use_ict = false;
2149 	spin_unlock_bh(&trans_pcie->irq_lock);
2150 }
2151 
2152 irqreturn_t iwl_pcie_isr(int irq, void *data)
2153 {
2154 	struct iwl_trans *trans = data;
2155 
2156 	if (!trans)
2157 		return IRQ_NONE;
2158 
2159 	/* Disable (but don't clear!) interrupts here to avoid
2160 	 * back-to-back ISRs and sporadic interrupts from our NIC.
2161 	 * If we have something to service, the tasklet will re-enable ints.
2162 	 * If we *don't* have something, we'll re-enable before leaving here.
2163 	 */
2164 	iwl_write32(trans, CSR_INT_MASK, 0x00000000);
2165 
2166 	return IRQ_WAKE_THREAD;
2167 }
2168 
2169 irqreturn_t iwl_pcie_msix_isr(int irq, void *data)
2170 {
2171 	return IRQ_WAKE_THREAD;
2172 }
2173 
2174 irqreturn_t iwl_pcie_irq_msix_handler(int irq, void *dev_id)
2175 {
2176 	struct msix_entry *entry = dev_id;
2177 	struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
2178 	struct iwl_trans *trans = trans_pcie->trans;
2179 	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
2180 	u32 inta_fh_msk = ~MSIX_FH_INT_CAUSES_DATA_QUEUE;
2181 	u32 inta_fh, inta_hw;
2182 	bool polling = false;
2183 
2184 	if (trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_NON_RX)
2185 		inta_fh_msk |= MSIX_FH_INT_CAUSES_Q0;
2186 
2187 	if (trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS)
2188 		inta_fh_msk |= MSIX_FH_INT_CAUSES_Q1;
2189 
2190 	lock_map_acquire(&trans->sync_cmd_lockdep_map);
2191 
2192 	spin_lock_bh(&trans_pcie->irq_lock);
2193 	inta_fh = iwl_read32(trans, CSR_MSIX_FH_INT_CAUSES_AD);
2194 	inta_hw = iwl_read32(trans, CSR_MSIX_HW_INT_CAUSES_AD);
2195 	/*
2196 	 * Clear causes registers to avoid being handling the same cause.
2197 	 */
2198 	iwl_write32(trans, CSR_MSIX_FH_INT_CAUSES_AD, inta_fh & inta_fh_msk);
2199 	iwl_write32(trans, CSR_MSIX_HW_INT_CAUSES_AD, inta_hw);
2200 	spin_unlock_bh(&trans_pcie->irq_lock);
2201 
2202 	trace_iwlwifi_dev_irq_msix(trans->dev, entry, true, inta_fh, inta_hw);
2203 
2204 	if (unlikely(!(inta_fh | inta_hw))) {
2205 		IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
2206 		lock_map_release(&trans->sync_cmd_lockdep_map);
2207 		return IRQ_NONE;
2208 	}
2209 
2210 	if (iwl_have_debug_level(IWL_DL_ISR)) {
2211 		IWL_DEBUG_ISR(trans,
2212 			      "ISR[%d] inta_fh 0x%08x, enabled (sw) 0x%08x (hw) 0x%08x\n",
2213 			      entry->entry, inta_fh, trans_pcie->fh_mask,
2214 			      iwl_read32(trans, CSR_MSIX_FH_INT_MASK_AD));
2215 		if (inta_fh & ~trans_pcie->fh_mask)
2216 			IWL_DEBUG_ISR(trans,
2217 				      "We got a masked interrupt (0x%08x)\n",
2218 				      inta_fh & ~trans_pcie->fh_mask);
2219 	}
2220 
2221 	inta_fh &= trans_pcie->fh_mask;
2222 
2223 	if ((trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_NON_RX) &&
2224 	    inta_fh & MSIX_FH_INT_CAUSES_Q0) {
2225 		local_bh_disable();
2226 		if (napi_schedule_prep(&trans_pcie->rxq[0].napi)) {
2227 			polling = true;
2228 			__napi_schedule(&trans_pcie->rxq[0].napi);
2229 		}
2230 		local_bh_enable();
2231 	}
2232 
2233 	if ((trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS) &&
2234 	    inta_fh & MSIX_FH_INT_CAUSES_Q1) {
2235 		local_bh_disable();
2236 		if (napi_schedule_prep(&trans_pcie->rxq[1].napi)) {
2237 			polling = true;
2238 			__napi_schedule(&trans_pcie->rxq[1].napi);
2239 		}
2240 		local_bh_enable();
2241 	}
2242 
2243 	/* This "Tx" DMA channel is used only for loading uCode */
2244 	if (inta_fh & MSIX_FH_INT_CAUSES_D2S_CH0_NUM) {
2245 		IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
2246 		isr_stats->tx++;
2247 		/*
2248 		 * Wake up uCode load routine,
2249 		 * now that load is complete
2250 		 */
2251 		trans_pcie->ucode_write_complete = true;
2252 		wake_up(&trans_pcie->ucode_write_waitq);
2253 	}
2254 
2255 	/* Error detected by uCode */
2256 	if ((inta_fh & MSIX_FH_INT_CAUSES_FH_ERR) ||
2257 	    (inta_hw & MSIX_HW_INT_CAUSES_REG_SW_ERR)) {
2258 		IWL_ERR(trans,
2259 			"Microcode SW error detected. Restarting 0x%X.\n",
2260 			inta_fh);
2261 		isr_stats->sw++;
2262 		iwl_pcie_irq_handle_error(trans);
2263 	}
2264 
2265 	/* After checking FH register check HW register */
2266 	if (iwl_have_debug_level(IWL_DL_ISR)) {
2267 		IWL_DEBUG_ISR(trans,
2268 			      "ISR[%d] inta_hw 0x%08x, enabled (sw) 0x%08x (hw) 0x%08x\n",
2269 			      entry->entry, inta_hw, trans_pcie->hw_mask,
2270 			      iwl_read32(trans, CSR_MSIX_HW_INT_MASK_AD));
2271 		if (inta_hw & ~trans_pcie->hw_mask)
2272 			IWL_DEBUG_ISR(trans,
2273 				      "We got a masked interrupt 0x%08x\n",
2274 				      inta_hw & ~trans_pcie->hw_mask);
2275 	}
2276 
2277 	inta_hw &= trans_pcie->hw_mask;
2278 
2279 	/* Alive notification via Rx interrupt will do the real work */
2280 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_ALIVE) {
2281 		IWL_DEBUG_ISR(trans, "Alive interrupt\n");
2282 		isr_stats->alive++;
2283 		if (trans->trans_cfg->gen2) {
2284 			/* We can restock, since firmware configured the RFH */
2285 			iwl_pcie_rxmq_restock(trans, trans_pcie->rxq);
2286 		}
2287 	}
2288 
2289 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_WAKEUP) {
2290 		u32 sleep_notif =
2291 			le32_to_cpu(trans_pcie->prph_info->sleep_notif);
2292 		if (sleep_notif == IWL_D3_SLEEP_STATUS_SUSPEND ||
2293 		    sleep_notif == IWL_D3_SLEEP_STATUS_RESUME) {
2294 			IWL_DEBUG_ISR(trans,
2295 				      "Sx interrupt: sleep notification = 0x%x\n",
2296 				      sleep_notif);
2297 			trans_pcie->sx_complete = true;
2298 			wake_up(&trans_pcie->sx_waitq);
2299 		} else {
2300 			/* uCode wakes up after power-down sleep */
2301 			IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
2302 			iwl_pcie_rxq_check_wrptr(trans);
2303 			iwl_pcie_txq_check_wrptrs(trans);
2304 
2305 			isr_stats->wakeup++;
2306 		}
2307 	}
2308 
2309 	/* Chip got too hot and stopped itself */
2310 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_CT_KILL) {
2311 		IWL_ERR(trans, "Microcode CT kill error detected.\n");
2312 		isr_stats->ctkill++;
2313 	}
2314 
2315 	/* HW RF KILL switch toggled */
2316 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_RF_KILL)
2317 		iwl_pcie_handle_rfkill_irq(trans);
2318 
2319 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_HW_ERR) {
2320 		IWL_ERR(trans,
2321 			"Hardware error detected. Restarting.\n");
2322 
2323 		isr_stats->hw++;
2324 		trans->dbg.hw_error = true;
2325 		iwl_pcie_irq_handle_error(trans);
2326 	}
2327 
2328 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_RESET_DONE) {
2329 		IWL_DEBUG_ISR(trans, "Reset flow completed\n");
2330 		trans_pcie->fw_reset_done = true;
2331 		wake_up(&trans_pcie->fw_reset_waitq);
2332 	}
2333 
2334 	if (!polling)
2335 		iwl_pcie_clear_irq(trans, entry->entry);
2336 
2337 	lock_map_release(&trans->sync_cmd_lockdep_map);
2338 
2339 	return IRQ_HANDLED;
2340 }
2341