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 	if (!trans_pcie->rx_pool)
491 		return;
492 
493 	for (i = 0; i < RX_POOL_SIZE(trans_pcie->num_rx_bufs); i++) {
494 		if (!trans_pcie->rx_pool[i].page)
495 			continue;
496 		dma_unmap_page(trans->dev, trans_pcie->rx_pool[i].page_dma,
497 			       trans_pcie->rx_buf_bytes, DMA_FROM_DEVICE);
498 		__free_pages(trans_pcie->rx_pool[i].page,
499 			     trans_pcie->rx_page_order);
500 		trans_pcie->rx_pool[i].page = NULL;
501 	}
502 }
503 
504 /*
505  * iwl_pcie_rx_allocator - Allocates pages in the background for RX queues
506  *
507  * Allocates for each received request 8 pages
508  * Called as a scheduled work item.
509  */
510 static void iwl_pcie_rx_allocator(struct iwl_trans *trans)
511 {
512 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
513 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
514 	struct list_head local_empty;
515 	int pending = atomic_read(&rba->req_pending);
516 
517 	IWL_DEBUG_TPT(trans, "Pending allocation requests = %d\n", pending);
518 
519 	/* If we were scheduled - there is at least one request */
520 	spin_lock_bh(&rba->lock);
521 	/* swap out the rba->rbd_empty to a local list */
522 	list_replace_init(&rba->rbd_empty, &local_empty);
523 	spin_unlock_bh(&rba->lock);
524 
525 	while (pending) {
526 		int i;
527 		LIST_HEAD(local_allocated);
528 		gfp_t gfp_mask = GFP_KERNEL;
529 
530 		/* Do not post a warning if there are only a few requests */
531 		if (pending < RX_PENDING_WATERMARK)
532 			gfp_mask |= __GFP_NOWARN;
533 
534 		for (i = 0; i < RX_CLAIM_REQ_ALLOC;) {
535 			struct iwl_rx_mem_buffer *rxb;
536 			struct page *page;
537 
538 			/* List should never be empty - each reused RBD is
539 			 * returned to the list, and initial pool covers any
540 			 * possible gap between the time the page is allocated
541 			 * to the time the RBD is added.
542 			 */
543 			BUG_ON(list_empty(&local_empty));
544 			/* Get the first rxb from the rbd list */
545 			rxb = list_first_entry(&local_empty,
546 					       struct iwl_rx_mem_buffer, list);
547 			BUG_ON(rxb->page);
548 
549 			/* Alloc a new receive buffer */
550 			page = iwl_pcie_rx_alloc_page(trans, &rxb->offset,
551 						      gfp_mask);
552 			if (!page)
553 				continue;
554 			rxb->page = page;
555 
556 			/* Get physical address of the RB */
557 			rxb->page_dma = dma_map_page(trans->dev, page,
558 						     rxb->offset,
559 						     trans_pcie->rx_buf_bytes,
560 						     DMA_FROM_DEVICE);
561 			if (dma_mapping_error(trans->dev, rxb->page_dma)) {
562 				rxb->page = NULL;
563 				__free_pages(page, trans_pcie->rx_page_order);
564 				continue;
565 			}
566 
567 			/* move the allocated entry to the out list */
568 			list_move(&rxb->list, &local_allocated);
569 			i++;
570 		}
571 
572 		atomic_dec(&rba->req_pending);
573 		pending--;
574 
575 		if (!pending) {
576 			pending = atomic_read(&rba->req_pending);
577 			if (pending)
578 				IWL_DEBUG_TPT(trans,
579 					      "Got more pending allocation requests = %d\n",
580 					      pending);
581 		}
582 
583 		spin_lock_bh(&rba->lock);
584 		/* add the allocated rbds to the allocator allocated list */
585 		list_splice_tail(&local_allocated, &rba->rbd_allocated);
586 		/* get more empty RBDs for current pending requests */
587 		list_splice_tail_init(&rba->rbd_empty, &local_empty);
588 		spin_unlock_bh(&rba->lock);
589 
590 		atomic_inc(&rba->req_ready);
591 
592 	}
593 
594 	spin_lock_bh(&rba->lock);
595 	/* return unused rbds to the allocator empty list */
596 	list_splice_tail(&local_empty, &rba->rbd_empty);
597 	spin_unlock_bh(&rba->lock);
598 
599 	IWL_DEBUG_TPT(trans, "%s, exit.\n", __func__);
600 }
601 
602 /*
603  * iwl_pcie_rx_allocator_get - returns the pre-allocated pages
604 .*
605 .* Called by queue when the queue posted allocation request and
606  * has freed 8 RBDs in order to restock itself.
607  * This function directly moves the allocated RBs to the queue's ownership
608  * and updates the relevant counters.
609  */
610 static void iwl_pcie_rx_allocator_get(struct iwl_trans *trans,
611 				      struct iwl_rxq *rxq)
612 {
613 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
614 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
615 	int i;
616 
617 	lockdep_assert_held(&rxq->lock);
618 
619 	/*
620 	 * atomic_dec_if_positive returns req_ready - 1 for any scenario.
621 	 * If req_ready is 0 atomic_dec_if_positive will return -1 and this
622 	 * function will return early, as there are no ready requests.
623 	 * atomic_dec_if_positive will perofrm the *actual* decrement only if
624 	 * req_ready > 0, i.e. - there are ready requests and the function
625 	 * hands one request to the caller.
626 	 */
627 	if (atomic_dec_if_positive(&rba->req_ready) < 0)
628 		return;
629 
630 	spin_lock(&rba->lock);
631 	for (i = 0; i < RX_CLAIM_REQ_ALLOC; i++) {
632 		/* Get next free Rx buffer, remove it from free list */
633 		struct iwl_rx_mem_buffer *rxb =
634 			list_first_entry(&rba->rbd_allocated,
635 					 struct iwl_rx_mem_buffer, list);
636 
637 		list_move(&rxb->list, &rxq->rx_free);
638 	}
639 	spin_unlock(&rba->lock);
640 
641 	rxq->used_count -= RX_CLAIM_REQ_ALLOC;
642 	rxq->free_count += RX_CLAIM_REQ_ALLOC;
643 }
644 
645 void iwl_pcie_rx_allocator_work(struct work_struct *data)
646 {
647 	struct iwl_rb_allocator *rba_p =
648 		container_of(data, struct iwl_rb_allocator, rx_alloc);
649 	struct iwl_trans_pcie *trans_pcie =
650 		container_of(rba_p, struct iwl_trans_pcie, rba);
651 
652 	iwl_pcie_rx_allocator(trans_pcie->trans);
653 }
654 
655 static int iwl_pcie_free_bd_size(struct iwl_trans *trans, bool use_rx_td)
656 {
657 	struct iwl_rx_transfer_desc *rx_td;
658 
659 	if (use_rx_td)
660 		return sizeof(*rx_td);
661 	else
662 		return trans->trans_cfg->mq_rx_supported ? sizeof(__le64) :
663 			sizeof(__le32);
664 }
665 
666 static void iwl_pcie_free_rxq_dma(struct iwl_trans *trans,
667 				  struct iwl_rxq *rxq)
668 {
669 	bool use_rx_td = (trans->trans_cfg->device_family >=
670 			  IWL_DEVICE_FAMILY_AX210);
671 	int free_size = iwl_pcie_free_bd_size(trans, use_rx_td);
672 
673 	if (rxq->bd)
674 		dma_free_coherent(trans->dev,
675 				  free_size * rxq->queue_size,
676 				  rxq->bd, rxq->bd_dma);
677 	rxq->bd_dma = 0;
678 	rxq->bd = NULL;
679 
680 	rxq->rb_stts_dma = 0;
681 	rxq->rb_stts = NULL;
682 
683 	if (rxq->used_bd)
684 		dma_free_coherent(trans->dev,
685 				  (use_rx_td ? sizeof(*rxq->cd) :
686 				   sizeof(__le32)) * rxq->queue_size,
687 				  rxq->used_bd, rxq->used_bd_dma);
688 	rxq->used_bd_dma = 0;
689 	rxq->used_bd = NULL;
690 }
691 
692 static int iwl_pcie_alloc_rxq_dma(struct iwl_trans *trans,
693 				  struct iwl_rxq *rxq)
694 {
695 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
696 	struct device *dev = trans->dev;
697 	int i;
698 	int free_size;
699 	bool use_rx_td = (trans->trans_cfg->device_family >=
700 			  IWL_DEVICE_FAMILY_AX210);
701 	size_t rb_stts_size = use_rx_td ? sizeof(__le16) :
702 			      sizeof(struct iwl_rb_status);
703 
704 	spin_lock_init(&rxq->lock);
705 	if (trans->trans_cfg->mq_rx_supported)
706 		rxq->queue_size = trans->cfg->num_rbds;
707 	else
708 		rxq->queue_size = RX_QUEUE_SIZE;
709 
710 	free_size = iwl_pcie_free_bd_size(trans, use_rx_td);
711 
712 	/*
713 	 * Allocate the circular buffer of Read Buffer Descriptors
714 	 * (RBDs)
715 	 */
716 	rxq->bd = dma_alloc_coherent(dev, free_size * rxq->queue_size,
717 				     &rxq->bd_dma, GFP_KERNEL);
718 	if (!rxq->bd)
719 		goto err;
720 
721 	if (trans->trans_cfg->mq_rx_supported) {
722 		rxq->used_bd = dma_alloc_coherent(dev,
723 						  (use_rx_td ? sizeof(*rxq->cd) : sizeof(__le32)) * rxq->queue_size,
724 						  &rxq->used_bd_dma,
725 						  GFP_KERNEL);
726 		if (!rxq->used_bd)
727 			goto err;
728 	}
729 
730 	rxq->rb_stts = trans_pcie->base_rb_stts + rxq->id * rb_stts_size;
731 	rxq->rb_stts_dma =
732 		trans_pcie->base_rb_stts_dma + rxq->id * rb_stts_size;
733 
734 	return 0;
735 
736 err:
737 	for (i = 0; i < trans->num_rx_queues; i++) {
738 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
739 
740 		iwl_pcie_free_rxq_dma(trans, rxq);
741 	}
742 
743 	return -ENOMEM;
744 }
745 
746 static int iwl_pcie_rx_alloc(struct iwl_trans *trans)
747 {
748 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
749 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
750 	int i, ret;
751 	size_t rb_stts_size = trans->trans_cfg->device_family >=
752 				IWL_DEVICE_FAMILY_AX210 ?
753 			      sizeof(__le16) : sizeof(struct iwl_rb_status);
754 
755 	if (WARN_ON(trans_pcie->rxq))
756 		return -EINVAL;
757 
758 	trans_pcie->rxq = kcalloc(trans->num_rx_queues, sizeof(struct iwl_rxq),
759 				  GFP_KERNEL);
760 	trans_pcie->rx_pool = kcalloc(RX_POOL_SIZE(trans_pcie->num_rx_bufs),
761 				      sizeof(trans_pcie->rx_pool[0]),
762 				      GFP_KERNEL);
763 	trans_pcie->global_table =
764 		kcalloc(RX_POOL_SIZE(trans_pcie->num_rx_bufs),
765 			sizeof(trans_pcie->global_table[0]),
766 			GFP_KERNEL);
767 	if (!trans_pcie->rxq || !trans_pcie->rx_pool ||
768 	    !trans_pcie->global_table) {
769 		ret = -ENOMEM;
770 		goto err;
771 	}
772 
773 	spin_lock_init(&rba->lock);
774 
775 	/*
776 	 * Allocate the driver's pointer to receive buffer status.
777 	 * Allocate for all queues continuously (HW requirement).
778 	 */
779 	trans_pcie->base_rb_stts =
780 			dma_alloc_coherent(trans->dev,
781 					   rb_stts_size * trans->num_rx_queues,
782 					   &trans_pcie->base_rb_stts_dma,
783 					   GFP_KERNEL);
784 	if (!trans_pcie->base_rb_stts) {
785 		ret = -ENOMEM;
786 		goto err;
787 	}
788 
789 	for (i = 0; i < trans->num_rx_queues; i++) {
790 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
791 
792 		rxq->id = i;
793 		ret = iwl_pcie_alloc_rxq_dma(trans, rxq);
794 		if (ret)
795 			goto err;
796 	}
797 	return 0;
798 
799 err:
800 	if (trans_pcie->base_rb_stts) {
801 		dma_free_coherent(trans->dev,
802 				  rb_stts_size * trans->num_rx_queues,
803 				  trans_pcie->base_rb_stts,
804 				  trans_pcie->base_rb_stts_dma);
805 		trans_pcie->base_rb_stts = NULL;
806 		trans_pcie->base_rb_stts_dma = 0;
807 	}
808 	kfree(trans_pcie->rx_pool);
809 	trans_pcie->rx_pool = NULL;
810 	kfree(trans_pcie->global_table);
811 	trans_pcie->global_table = NULL;
812 	kfree(trans_pcie->rxq);
813 	trans_pcie->rxq = NULL;
814 
815 	return ret;
816 }
817 
818 static void iwl_pcie_rx_hw_init(struct iwl_trans *trans, struct iwl_rxq *rxq)
819 {
820 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
821 	u32 rb_size;
822 	const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
823 
824 	switch (trans_pcie->rx_buf_size) {
825 	case IWL_AMSDU_4K:
826 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
827 		break;
828 	case IWL_AMSDU_8K:
829 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
830 		break;
831 	case IWL_AMSDU_12K:
832 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_12K;
833 		break;
834 	default:
835 		WARN_ON(1);
836 		rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
837 	}
838 
839 	if (!iwl_trans_grab_nic_access(trans))
840 		return;
841 
842 	/* Stop Rx DMA */
843 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
844 	/* reset and flush pointers */
845 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_RBDCB_WPTR, 0);
846 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_FLUSH_RB_REQ, 0);
847 	iwl_write32(trans, FH_RSCSR_CHNL0_RDPTR, 0);
848 
849 	/* Reset driver's Rx queue write index */
850 	iwl_write32(trans, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
851 
852 	/* Tell device where to find RBD circular buffer in DRAM */
853 	iwl_write32(trans, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
854 		    (u32)(rxq->bd_dma >> 8));
855 
856 	/* Tell device where in DRAM to update its Rx status */
857 	iwl_write32(trans, FH_RSCSR_CHNL0_STTS_WPTR_REG,
858 		    rxq->rb_stts_dma >> 4);
859 
860 	/* Enable Rx DMA
861 	 * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in
862 	 *      the credit mechanism in 5000 HW RX FIFO
863 	 * Direct rx interrupts to hosts
864 	 * Rx buffer size 4 or 8k or 12k
865 	 * RB timeout 0x10
866 	 * 256 RBDs
867 	 */
868 	iwl_write32(trans, FH_MEM_RCSR_CHNL0_CONFIG_REG,
869 		    FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
870 		    FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY |
871 		    FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
872 		    rb_size |
873 		    (RX_RB_TIMEOUT << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS) |
874 		    (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));
875 
876 	iwl_trans_release_nic_access(trans);
877 
878 	/* Set interrupt coalescing timer to default (2048 usecs) */
879 	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
880 
881 	/* W/A for interrupt coalescing bug in 7260 and 3160 */
882 	if (trans->cfg->host_interrupt_operation_mode)
883 		iwl_set_bit(trans, CSR_INT_COALESCING, IWL_HOST_INT_OPER_MODE);
884 }
885 
886 static void iwl_pcie_rx_mq_hw_init(struct iwl_trans *trans)
887 {
888 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
889 	u32 rb_size, enabled = 0;
890 	int i;
891 
892 	switch (trans_pcie->rx_buf_size) {
893 	case IWL_AMSDU_2K:
894 		rb_size = RFH_RXF_DMA_RB_SIZE_2K;
895 		break;
896 	case IWL_AMSDU_4K:
897 		rb_size = RFH_RXF_DMA_RB_SIZE_4K;
898 		break;
899 	case IWL_AMSDU_8K:
900 		rb_size = RFH_RXF_DMA_RB_SIZE_8K;
901 		break;
902 	case IWL_AMSDU_12K:
903 		rb_size = RFH_RXF_DMA_RB_SIZE_12K;
904 		break;
905 	default:
906 		WARN_ON(1);
907 		rb_size = RFH_RXF_DMA_RB_SIZE_4K;
908 	}
909 
910 	if (!iwl_trans_grab_nic_access(trans))
911 		return;
912 
913 	/* Stop Rx DMA */
914 	iwl_write_prph_no_grab(trans, RFH_RXF_DMA_CFG, 0);
915 	/* disable free amd used rx queue operation */
916 	iwl_write_prph_no_grab(trans, RFH_RXF_RXQ_ACTIVE, 0);
917 
918 	for (i = 0; i < trans->num_rx_queues; i++) {
919 		/* Tell device where to find RBD free table in DRAM */
920 		iwl_write_prph64_no_grab(trans,
921 					 RFH_Q_FRBDCB_BA_LSB(i),
922 					 trans_pcie->rxq[i].bd_dma);
923 		/* Tell device where to find RBD used table in DRAM */
924 		iwl_write_prph64_no_grab(trans,
925 					 RFH_Q_URBDCB_BA_LSB(i),
926 					 trans_pcie->rxq[i].used_bd_dma);
927 		/* Tell device where in DRAM to update its Rx status */
928 		iwl_write_prph64_no_grab(trans,
929 					 RFH_Q_URBD_STTS_WPTR_LSB(i),
930 					 trans_pcie->rxq[i].rb_stts_dma);
931 		/* Reset device indice tables */
932 		iwl_write_prph_no_grab(trans, RFH_Q_FRBDCB_WIDX(i), 0);
933 		iwl_write_prph_no_grab(trans, RFH_Q_FRBDCB_RIDX(i), 0);
934 		iwl_write_prph_no_grab(trans, RFH_Q_URBDCB_WIDX(i), 0);
935 
936 		enabled |= BIT(i) | BIT(i + 16);
937 	}
938 
939 	/*
940 	 * Enable Rx DMA
941 	 * Rx buffer size 4 or 8k or 12k
942 	 * Min RB size 4 or 8
943 	 * Drop frames that exceed RB size
944 	 * 512 RBDs
945 	 */
946 	iwl_write_prph_no_grab(trans, RFH_RXF_DMA_CFG,
947 			       RFH_DMA_EN_ENABLE_VAL | rb_size |
948 			       RFH_RXF_DMA_MIN_RB_4_8 |
949 			       RFH_RXF_DMA_DROP_TOO_LARGE_MASK |
950 			       RFH_RXF_DMA_RBDCB_SIZE_512);
951 
952 	/*
953 	 * Activate DMA snooping.
954 	 * Set RX DMA chunk size to 64B for IOSF and 128B for PCIe
955 	 * Default queue is 0
956 	 */
957 	iwl_write_prph_no_grab(trans, RFH_GEN_CFG,
958 			       RFH_GEN_CFG_RFH_DMA_SNOOP |
959 			       RFH_GEN_CFG_VAL(DEFAULT_RXQ_NUM, 0) |
960 			       RFH_GEN_CFG_SERVICE_DMA_SNOOP |
961 			       RFH_GEN_CFG_VAL(RB_CHUNK_SIZE,
962 					       trans->trans_cfg->integrated ?
963 					       RFH_GEN_CFG_RB_CHUNK_SIZE_64 :
964 					       RFH_GEN_CFG_RB_CHUNK_SIZE_128));
965 	/* Enable the relevant rx queues */
966 	iwl_write_prph_no_grab(trans, RFH_RXF_RXQ_ACTIVE, enabled);
967 
968 	iwl_trans_release_nic_access(trans);
969 
970 	/* Set interrupt coalescing timer to default (2048 usecs) */
971 	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
972 }
973 
974 void iwl_pcie_rx_init_rxb_lists(struct iwl_rxq *rxq)
975 {
976 	lockdep_assert_held(&rxq->lock);
977 
978 	INIT_LIST_HEAD(&rxq->rx_free);
979 	INIT_LIST_HEAD(&rxq->rx_used);
980 	rxq->free_count = 0;
981 	rxq->used_count = 0;
982 }
983 
984 static int iwl_pcie_rx_handle(struct iwl_trans *trans, int queue, int budget);
985 
986 static int iwl_pcie_napi_poll(struct napi_struct *napi, int budget)
987 {
988 	struct iwl_rxq *rxq = container_of(napi, struct iwl_rxq, napi);
989 	struct iwl_trans_pcie *trans_pcie;
990 	struct iwl_trans *trans;
991 	int ret;
992 
993 	trans_pcie = container_of(napi->dev, struct iwl_trans_pcie, napi_dev);
994 	trans = trans_pcie->trans;
995 
996 	ret = iwl_pcie_rx_handle(trans, rxq->id, budget);
997 
998 	IWL_DEBUG_ISR(trans, "[%d] handled %d, budget %d\n",
999 		      rxq->id, ret, budget);
1000 
1001 	if (ret < budget) {
1002 		spin_lock(&trans_pcie->irq_lock);
1003 		if (test_bit(STATUS_INT_ENABLED, &trans->status))
1004 			_iwl_enable_interrupts(trans);
1005 		spin_unlock(&trans_pcie->irq_lock);
1006 
1007 		napi_complete_done(&rxq->napi, ret);
1008 	}
1009 
1010 	return ret;
1011 }
1012 
1013 static int iwl_pcie_napi_poll_msix(struct napi_struct *napi, int budget)
1014 {
1015 	struct iwl_rxq *rxq = container_of(napi, struct iwl_rxq, napi);
1016 	struct iwl_trans_pcie *trans_pcie;
1017 	struct iwl_trans *trans;
1018 	int ret;
1019 
1020 	trans_pcie = container_of(napi->dev, struct iwl_trans_pcie, napi_dev);
1021 	trans = trans_pcie->trans;
1022 
1023 	ret = iwl_pcie_rx_handle(trans, rxq->id, budget);
1024 	IWL_DEBUG_ISR(trans, "[%d] handled %d, budget %d\n", rxq->id, ret,
1025 		      budget);
1026 
1027 	if (ret < budget) {
1028 		int irq_line = rxq->id;
1029 
1030 		/* FIRST_RSS is shared with line 0 */
1031 		if (trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS &&
1032 		    rxq->id == 1)
1033 			irq_line = 0;
1034 
1035 		spin_lock(&trans_pcie->irq_lock);
1036 		iwl_pcie_clear_irq(trans, irq_line);
1037 		spin_unlock(&trans_pcie->irq_lock);
1038 
1039 		napi_complete_done(&rxq->napi, ret);
1040 	}
1041 
1042 	return ret;
1043 }
1044 
1045 static int _iwl_pcie_rx_init(struct iwl_trans *trans)
1046 {
1047 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1048 	struct iwl_rxq *def_rxq;
1049 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
1050 	int i, err, queue_size, allocator_pool_size, num_alloc;
1051 
1052 	if (!trans_pcie->rxq) {
1053 		err = iwl_pcie_rx_alloc(trans);
1054 		if (err)
1055 			return err;
1056 	}
1057 	def_rxq = trans_pcie->rxq;
1058 
1059 	cancel_work_sync(&rba->rx_alloc);
1060 
1061 	spin_lock_bh(&rba->lock);
1062 	atomic_set(&rba->req_pending, 0);
1063 	atomic_set(&rba->req_ready, 0);
1064 	INIT_LIST_HEAD(&rba->rbd_allocated);
1065 	INIT_LIST_HEAD(&rba->rbd_empty);
1066 	spin_unlock_bh(&rba->lock);
1067 
1068 	/* free all first - we overwrite everything here */
1069 	iwl_pcie_free_rbs_pool(trans);
1070 
1071 	for (i = 0; i < RX_QUEUE_SIZE; i++)
1072 		def_rxq->queue[i] = NULL;
1073 
1074 	for (i = 0; i < trans->num_rx_queues; i++) {
1075 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
1076 
1077 		spin_lock_bh(&rxq->lock);
1078 		/*
1079 		 * Set read write pointer to reflect that we have processed
1080 		 * and used all buffers, but have not restocked the Rx queue
1081 		 * with fresh buffers
1082 		 */
1083 		rxq->read = 0;
1084 		rxq->write = 0;
1085 		rxq->write_actual = 0;
1086 		memset(rxq->rb_stts, 0,
1087 		       (trans->trans_cfg->device_family >=
1088 			IWL_DEVICE_FAMILY_AX210) ?
1089 		       sizeof(__le16) : sizeof(struct iwl_rb_status));
1090 
1091 		iwl_pcie_rx_init_rxb_lists(rxq);
1092 
1093 		spin_unlock_bh(&rxq->lock);
1094 
1095 		if (!rxq->napi.poll) {
1096 			int (*poll)(struct napi_struct *, int) = iwl_pcie_napi_poll;
1097 
1098 			if (trans_pcie->msix_enabled)
1099 				poll = iwl_pcie_napi_poll_msix;
1100 
1101 			netif_napi_add(&trans_pcie->napi_dev, &rxq->napi,
1102 				       poll, NAPI_POLL_WEIGHT);
1103 			napi_enable(&rxq->napi);
1104 		}
1105 
1106 	}
1107 
1108 	/* move the pool to the default queue and allocator ownerships */
1109 	queue_size = trans->trans_cfg->mq_rx_supported ?
1110 			trans_pcie->num_rx_bufs - 1 : RX_QUEUE_SIZE;
1111 	allocator_pool_size = trans->num_rx_queues *
1112 		(RX_CLAIM_REQ_ALLOC - RX_POST_REQ_ALLOC);
1113 	num_alloc = queue_size + allocator_pool_size;
1114 
1115 	for (i = 0; i < num_alloc; i++) {
1116 		struct iwl_rx_mem_buffer *rxb = &trans_pcie->rx_pool[i];
1117 
1118 		if (i < allocator_pool_size)
1119 			list_add(&rxb->list, &rba->rbd_empty);
1120 		else
1121 			list_add(&rxb->list, &def_rxq->rx_used);
1122 		trans_pcie->global_table[i] = rxb;
1123 		rxb->vid = (u16)(i + 1);
1124 		rxb->invalid = true;
1125 	}
1126 
1127 	iwl_pcie_rxq_alloc_rbs(trans, GFP_KERNEL, def_rxq);
1128 
1129 	return 0;
1130 }
1131 
1132 int iwl_pcie_rx_init(struct iwl_trans *trans)
1133 {
1134 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1135 	int ret = _iwl_pcie_rx_init(trans);
1136 
1137 	if (ret)
1138 		return ret;
1139 
1140 	if (trans->trans_cfg->mq_rx_supported)
1141 		iwl_pcie_rx_mq_hw_init(trans);
1142 	else
1143 		iwl_pcie_rx_hw_init(trans, trans_pcie->rxq);
1144 
1145 	iwl_pcie_rxq_restock(trans, trans_pcie->rxq);
1146 
1147 	spin_lock_bh(&trans_pcie->rxq->lock);
1148 	iwl_pcie_rxq_inc_wr_ptr(trans, trans_pcie->rxq);
1149 	spin_unlock_bh(&trans_pcie->rxq->lock);
1150 
1151 	return 0;
1152 }
1153 
1154 int iwl_pcie_gen2_rx_init(struct iwl_trans *trans)
1155 {
1156 	/* Set interrupt coalescing timer to default (2048 usecs) */
1157 	iwl_write8(trans, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
1158 
1159 	/*
1160 	 * We don't configure the RFH.
1161 	 * Restock will be done at alive, after firmware configured the RFH.
1162 	 */
1163 	return _iwl_pcie_rx_init(trans);
1164 }
1165 
1166 void iwl_pcie_rx_free(struct iwl_trans *trans)
1167 {
1168 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1169 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
1170 	int i;
1171 	size_t rb_stts_size = trans->trans_cfg->device_family >=
1172 				IWL_DEVICE_FAMILY_AX210 ?
1173 			      sizeof(__le16) : sizeof(struct iwl_rb_status);
1174 
1175 	/*
1176 	 * if rxq is NULL, it means that nothing has been allocated,
1177 	 * exit now
1178 	 */
1179 	if (!trans_pcie->rxq) {
1180 		IWL_DEBUG_INFO(trans, "Free NULL rx context\n");
1181 		return;
1182 	}
1183 
1184 	cancel_work_sync(&rba->rx_alloc);
1185 
1186 	iwl_pcie_free_rbs_pool(trans);
1187 
1188 	if (trans_pcie->base_rb_stts) {
1189 		dma_free_coherent(trans->dev,
1190 				  rb_stts_size * trans->num_rx_queues,
1191 				  trans_pcie->base_rb_stts,
1192 				  trans_pcie->base_rb_stts_dma);
1193 		trans_pcie->base_rb_stts = NULL;
1194 		trans_pcie->base_rb_stts_dma = 0;
1195 	}
1196 
1197 	for (i = 0; i < trans->num_rx_queues; i++) {
1198 		struct iwl_rxq *rxq = &trans_pcie->rxq[i];
1199 
1200 		iwl_pcie_free_rxq_dma(trans, rxq);
1201 
1202 		if (rxq->napi.poll) {
1203 			napi_disable(&rxq->napi);
1204 			netif_napi_del(&rxq->napi);
1205 		}
1206 	}
1207 	kfree(trans_pcie->rx_pool);
1208 	kfree(trans_pcie->global_table);
1209 	kfree(trans_pcie->rxq);
1210 
1211 	if (trans_pcie->alloc_page)
1212 		__free_pages(trans_pcie->alloc_page, trans_pcie->rx_page_order);
1213 }
1214 
1215 static void iwl_pcie_rx_move_to_allocator(struct iwl_rxq *rxq,
1216 					  struct iwl_rb_allocator *rba)
1217 {
1218 	spin_lock(&rba->lock);
1219 	list_splice_tail_init(&rxq->rx_used, &rba->rbd_empty);
1220 	spin_unlock(&rba->lock);
1221 }
1222 
1223 /*
1224  * iwl_pcie_rx_reuse_rbd - Recycle used RBDs
1225  *
1226  * Called when a RBD can be reused. The RBD is transferred to the allocator.
1227  * When there are 2 empty RBDs - a request for allocation is posted
1228  */
1229 static void iwl_pcie_rx_reuse_rbd(struct iwl_trans *trans,
1230 				  struct iwl_rx_mem_buffer *rxb,
1231 				  struct iwl_rxq *rxq, bool emergency)
1232 {
1233 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1234 	struct iwl_rb_allocator *rba = &trans_pcie->rba;
1235 
1236 	/* Move the RBD to the used list, will be moved to allocator in batches
1237 	 * before claiming or posting a request*/
1238 	list_add_tail(&rxb->list, &rxq->rx_used);
1239 
1240 	if (unlikely(emergency))
1241 		return;
1242 
1243 	/* Count the allocator owned RBDs */
1244 	rxq->used_count++;
1245 
1246 	/* If we have RX_POST_REQ_ALLOC new released rx buffers -
1247 	 * issue a request for allocator. Modulo RX_CLAIM_REQ_ALLOC is
1248 	 * used for the case we failed to claim RX_CLAIM_REQ_ALLOC,
1249 	 * after but we still need to post another request.
1250 	 */
1251 	if ((rxq->used_count % RX_CLAIM_REQ_ALLOC) == RX_POST_REQ_ALLOC) {
1252 		/* Move the 2 RBDs to the allocator ownership.
1253 		 Allocator has another 6 from pool for the request completion*/
1254 		iwl_pcie_rx_move_to_allocator(rxq, rba);
1255 
1256 		atomic_inc(&rba->req_pending);
1257 		queue_work(rba->alloc_wq, &rba->rx_alloc);
1258 	}
1259 }
1260 
1261 static void iwl_pcie_rx_handle_rb(struct iwl_trans *trans,
1262 				struct iwl_rxq *rxq,
1263 				struct iwl_rx_mem_buffer *rxb,
1264 				bool emergency,
1265 				int i)
1266 {
1267 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1268 	struct iwl_txq *txq = trans->txqs.txq[trans->txqs.cmd.q_id];
1269 	bool page_stolen = false;
1270 	int max_len = trans_pcie->rx_buf_bytes;
1271 	u32 offset = 0;
1272 
1273 	if (WARN_ON(!rxb))
1274 		return;
1275 
1276 	dma_unmap_page(trans->dev, rxb->page_dma, max_len, DMA_FROM_DEVICE);
1277 
1278 	while (offset + sizeof(u32) + sizeof(struct iwl_cmd_header) < max_len) {
1279 		struct iwl_rx_packet *pkt;
1280 		bool reclaim;
1281 		int len;
1282 		struct iwl_rx_cmd_buffer rxcb = {
1283 			._offset = rxb->offset + offset,
1284 			._rx_page_order = trans_pcie->rx_page_order,
1285 			._page = rxb->page,
1286 			._page_stolen = false,
1287 			.truesize = max_len,
1288 		};
1289 
1290 		pkt = rxb_addr(&rxcb);
1291 
1292 		if (pkt->len_n_flags == cpu_to_le32(FH_RSCSR_FRAME_INVALID)) {
1293 			IWL_DEBUG_RX(trans,
1294 				     "Q %d: RB end marker at offset %d\n",
1295 				     rxq->id, offset);
1296 			break;
1297 		}
1298 
1299 		WARN((le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_RXQ_MASK) >>
1300 			FH_RSCSR_RXQ_POS != rxq->id,
1301 		     "frame on invalid queue - is on %d and indicates %d\n",
1302 		     rxq->id,
1303 		     (le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_RXQ_MASK) >>
1304 			FH_RSCSR_RXQ_POS);
1305 
1306 		IWL_DEBUG_RX(trans,
1307 			     "Q %d: cmd at offset %d: %s (%.2x.%2x, seq 0x%x)\n",
1308 			     rxq->id, offset,
1309 			     iwl_get_cmd_string(trans,
1310 						WIDE_ID(pkt->hdr.group_id, pkt->hdr.cmd)),
1311 			     pkt->hdr.group_id, pkt->hdr.cmd,
1312 			     le16_to_cpu(pkt->hdr.sequence));
1313 
1314 		len = iwl_rx_packet_len(pkt);
1315 		len += sizeof(u32); /* account for status word */
1316 
1317 		offset += ALIGN(len, FH_RSCSR_FRAME_ALIGN);
1318 
1319 		/* check that what the device tells us made sense */
1320 		if (offset > max_len)
1321 			break;
1322 
1323 		trace_iwlwifi_dev_rx(trans->dev, trans, pkt, len);
1324 		trace_iwlwifi_dev_rx_data(trans->dev, trans, pkt, len);
1325 
1326 		/* Reclaim a command buffer only if this packet is a response
1327 		 *   to a (driver-originated) command.
1328 		 * If the packet (e.g. Rx frame) originated from uCode,
1329 		 *   there is no command buffer to reclaim.
1330 		 * Ucode should set SEQ_RX_FRAME bit if ucode-originated,
1331 		 *   but apparently a few don't get set; catch them here. */
1332 		reclaim = !(pkt->hdr.sequence & SEQ_RX_FRAME);
1333 		if (reclaim && !pkt->hdr.group_id) {
1334 			int i;
1335 
1336 			for (i = 0; i < trans_pcie->n_no_reclaim_cmds; i++) {
1337 				if (trans_pcie->no_reclaim_cmds[i] ==
1338 							pkt->hdr.cmd) {
1339 					reclaim = false;
1340 					break;
1341 				}
1342 			}
1343 		}
1344 
1345 		if (rxq->id == trans_pcie->def_rx_queue)
1346 			iwl_op_mode_rx(trans->op_mode, &rxq->napi,
1347 				       &rxcb);
1348 		else
1349 			iwl_op_mode_rx_rss(trans->op_mode, &rxq->napi,
1350 					   &rxcb, rxq->id);
1351 
1352 		/*
1353 		 * After here, we should always check rxcb._page_stolen,
1354 		 * if it is true then one of the handlers took the page.
1355 		 */
1356 
1357 		if (reclaim) {
1358 			u16 sequence = le16_to_cpu(pkt->hdr.sequence);
1359 			int index = SEQ_TO_INDEX(sequence);
1360 			int cmd_index = iwl_txq_get_cmd_index(txq, index);
1361 
1362 			kfree_sensitive(txq->entries[cmd_index].free_buf);
1363 			txq->entries[cmd_index].free_buf = NULL;
1364 
1365 			/* Invoke any callbacks, transfer the buffer to caller,
1366 			 * and fire off the (possibly) blocking
1367 			 * iwl_trans_send_cmd()
1368 			 * as we reclaim the driver command queue */
1369 			if (!rxcb._page_stolen)
1370 				iwl_pcie_hcmd_complete(trans, &rxcb);
1371 			else
1372 				IWL_WARN(trans, "Claim null rxb?\n");
1373 		}
1374 
1375 		page_stolen |= rxcb._page_stolen;
1376 		if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
1377 			break;
1378 	}
1379 
1380 	/* page was stolen from us -- free our reference */
1381 	if (page_stolen) {
1382 		__free_pages(rxb->page, trans_pcie->rx_page_order);
1383 		rxb->page = NULL;
1384 	}
1385 
1386 	/* Reuse the page if possible. For notification packets and
1387 	 * SKBs that fail to Rx correctly, add them back into the
1388 	 * rx_free list for reuse later. */
1389 	if (rxb->page != NULL) {
1390 		rxb->page_dma =
1391 			dma_map_page(trans->dev, rxb->page, rxb->offset,
1392 				     trans_pcie->rx_buf_bytes,
1393 				     DMA_FROM_DEVICE);
1394 		if (dma_mapping_error(trans->dev, rxb->page_dma)) {
1395 			/*
1396 			 * free the page(s) as well to not break
1397 			 * the invariant that the items on the used
1398 			 * list have no page(s)
1399 			 */
1400 			__free_pages(rxb->page, trans_pcie->rx_page_order);
1401 			rxb->page = NULL;
1402 			iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
1403 		} else {
1404 			list_add_tail(&rxb->list, &rxq->rx_free);
1405 			rxq->free_count++;
1406 		}
1407 	} else
1408 		iwl_pcie_rx_reuse_rbd(trans, rxb, rxq, emergency);
1409 }
1410 
1411 static struct iwl_rx_mem_buffer *iwl_pcie_get_rxb(struct iwl_trans *trans,
1412 						  struct iwl_rxq *rxq, int i,
1413 						  bool *join)
1414 {
1415 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1416 	struct iwl_rx_mem_buffer *rxb;
1417 	u16 vid;
1418 
1419 	BUILD_BUG_ON(sizeof(struct iwl_rx_completion_desc) != 32);
1420 
1421 	if (!trans->trans_cfg->mq_rx_supported) {
1422 		rxb = rxq->queue[i];
1423 		rxq->queue[i] = NULL;
1424 		return rxb;
1425 	}
1426 
1427 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210) {
1428 		vid = le16_to_cpu(rxq->cd[i].rbid);
1429 		*join = rxq->cd[i].flags & IWL_RX_CD_FLAGS_FRAGMENTED;
1430 	} else {
1431 		vid = le32_to_cpu(rxq->bd_32[i]) & 0x0FFF; /* 12-bit VID */
1432 	}
1433 
1434 	if (!vid || vid > RX_POOL_SIZE(trans_pcie->num_rx_bufs))
1435 		goto out_err;
1436 
1437 	rxb = trans_pcie->global_table[vid - 1];
1438 	if (rxb->invalid)
1439 		goto out_err;
1440 
1441 	IWL_DEBUG_RX(trans, "Got virtual RB ID %u\n", (u32)rxb->vid);
1442 
1443 	rxb->invalid = true;
1444 
1445 	return rxb;
1446 
1447 out_err:
1448 	WARN(1, "Invalid rxb from HW %u\n", (u32)vid);
1449 	iwl_force_nmi(trans);
1450 	return NULL;
1451 }
1452 
1453 /*
1454  * iwl_pcie_rx_handle - Main entry function for receiving responses from fw
1455  */
1456 static int iwl_pcie_rx_handle(struct iwl_trans *trans, int queue, int budget)
1457 {
1458 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1459 	struct iwl_rxq *rxq;
1460 	u32 r, i, count = 0, handled = 0;
1461 	bool emergency = false;
1462 
1463 	if (WARN_ON_ONCE(!trans_pcie->rxq || !trans_pcie->rxq[queue].bd))
1464 		return budget;
1465 
1466 	rxq = &trans_pcie->rxq[queue];
1467 
1468 restart:
1469 	spin_lock(&rxq->lock);
1470 	/* uCode's read index (stored in shared DRAM) indicates the last Rx
1471 	 * buffer that the driver may process (last buffer filled by ucode). */
1472 	r = le16_to_cpu(iwl_get_closed_rb_stts(trans, rxq)) & 0x0FFF;
1473 	i = rxq->read;
1474 
1475 	/* W/A 9000 device step A0 wrap-around bug */
1476 	r &= (rxq->queue_size - 1);
1477 
1478 	/* Rx interrupt, but nothing sent from uCode */
1479 	if (i == r)
1480 		IWL_DEBUG_RX(trans, "Q %d: HW = SW = %d\n", rxq->id, r);
1481 
1482 	while (i != r && ++handled < budget) {
1483 		struct iwl_rb_allocator *rba = &trans_pcie->rba;
1484 		struct iwl_rx_mem_buffer *rxb;
1485 		/* number of RBDs still waiting for page allocation */
1486 		u32 rb_pending_alloc =
1487 			atomic_read(&trans_pcie->rba.req_pending) *
1488 			RX_CLAIM_REQ_ALLOC;
1489 		bool join = false;
1490 
1491 		if (unlikely(rb_pending_alloc >= rxq->queue_size / 2 &&
1492 			     !emergency)) {
1493 			iwl_pcie_rx_move_to_allocator(rxq, rba);
1494 			emergency = true;
1495 			IWL_DEBUG_TPT(trans,
1496 				      "RX path is in emergency. Pending allocations %d\n",
1497 				      rb_pending_alloc);
1498 		}
1499 
1500 		IWL_DEBUG_RX(trans, "Q %d: HW = %d, SW = %d\n", rxq->id, r, i);
1501 
1502 		rxb = iwl_pcie_get_rxb(trans, rxq, i, &join);
1503 		if (!rxb)
1504 			goto out;
1505 
1506 		if (unlikely(join || rxq->next_rb_is_fragment)) {
1507 			rxq->next_rb_is_fragment = join;
1508 			/*
1509 			 * We can only get a multi-RB in the following cases:
1510 			 *  - firmware issue, sending a too big notification
1511 			 *  - sniffer mode with a large A-MSDU
1512 			 *  - large MTU frames (>2k)
1513 			 * since the multi-RB functionality is limited to newer
1514 			 * hardware that cannot put multiple entries into a
1515 			 * single RB.
1516 			 *
1517 			 * Right now, the higher layers aren't set up to deal
1518 			 * with that, so discard all of these.
1519 			 */
1520 			list_add_tail(&rxb->list, &rxq->rx_free);
1521 			rxq->free_count++;
1522 		} else {
1523 			iwl_pcie_rx_handle_rb(trans, rxq, rxb, emergency, i);
1524 		}
1525 
1526 		i = (i + 1) & (rxq->queue_size - 1);
1527 
1528 		/*
1529 		 * If we have RX_CLAIM_REQ_ALLOC released rx buffers -
1530 		 * try to claim the pre-allocated buffers from the allocator.
1531 		 * If not ready - will try to reclaim next time.
1532 		 * There is no need to reschedule work - allocator exits only
1533 		 * on success
1534 		 */
1535 		if (rxq->used_count >= RX_CLAIM_REQ_ALLOC)
1536 			iwl_pcie_rx_allocator_get(trans, rxq);
1537 
1538 		if (rxq->used_count % RX_CLAIM_REQ_ALLOC == 0 && !emergency) {
1539 			/* Add the remaining empty RBDs for allocator use */
1540 			iwl_pcie_rx_move_to_allocator(rxq, rba);
1541 		} else if (emergency) {
1542 			count++;
1543 			if (count == 8) {
1544 				count = 0;
1545 				if (rb_pending_alloc < rxq->queue_size / 3) {
1546 					IWL_DEBUG_TPT(trans,
1547 						      "RX path exited emergency. Pending allocations %d\n",
1548 						      rb_pending_alloc);
1549 					emergency = false;
1550 				}
1551 
1552 				rxq->read = i;
1553 				spin_unlock(&rxq->lock);
1554 				iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
1555 				iwl_pcie_rxq_restock(trans, rxq);
1556 				goto restart;
1557 			}
1558 		}
1559 	}
1560 out:
1561 	/* Backtrack one entry */
1562 	rxq->read = i;
1563 	spin_unlock(&rxq->lock);
1564 
1565 	/*
1566 	 * handle a case where in emergency there are some unallocated RBDs.
1567 	 * those RBDs are in the used list, but are not tracked by the queue's
1568 	 * used_count which counts allocator owned RBDs.
1569 	 * unallocated emergency RBDs must be allocated on exit, otherwise
1570 	 * when called again the function may not be in emergency mode and
1571 	 * they will be handed to the allocator with no tracking in the RBD
1572 	 * allocator counters, which will lead to them never being claimed back
1573 	 * by the queue.
1574 	 * by allocating them here, they are now in the queue free list, and
1575 	 * will be restocked by the next call of iwl_pcie_rxq_restock.
1576 	 */
1577 	if (unlikely(emergency && count))
1578 		iwl_pcie_rxq_alloc_rbs(trans, GFP_ATOMIC, rxq);
1579 
1580 	iwl_pcie_rxq_restock(trans, rxq);
1581 
1582 	return handled;
1583 }
1584 
1585 static struct iwl_trans_pcie *iwl_pcie_get_trans_pcie(struct msix_entry *entry)
1586 {
1587 	u8 queue = entry->entry;
1588 	struct msix_entry *entries = entry - queue;
1589 
1590 	return container_of(entries, struct iwl_trans_pcie, msix_entries[0]);
1591 }
1592 
1593 /*
1594  * iwl_pcie_rx_msix_handle - Main entry function for receiving responses from fw
1595  * This interrupt handler should be used with RSS queue only.
1596  */
1597 irqreturn_t iwl_pcie_irq_rx_msix_handler(int irq, void *dev_id)
1598 {
1599 	struct msix_entry *entry = dev_id;
1600 	struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
1601 	struct iwl_trans *trans = trans_pcie->trans;
1602 	struct iwl_rxq *rxq = &trans_pcie->rxq[entry->entry];
1603 
1604 	trace_iwlwifi_dev_irq_msix(trans->dev, entry, false, 0, 0);
1605 
1606 	if (WARN_ON(entry->entry >= trans->num_rx_queues))
1607 		return IRQ_NONE;
1608 
1609 	if (WARN_ONCE(!rxq,
1610 		      "[%d] Got MSI-X interrupt before we have Rx queues",
1611 		      entry->entry))
1612 		return IRQ_NONE;
1613 
1614 	lock_map_acquire(&trans->sync_cmd_lockdep_map);
1615 	IWL_DEBUG_ISR(trans, "[%d] Got interrupt\n", entry->entry);
1616 
1617 	local_bh_disable();
1618 	if (napi_schedule_prep(&rxq->napi))
1619 		__napi_schedule(&rxq->napi);
1620 	else
1621 		iwl_pcie_clear_irq(trans, entry->entry);
1622 	local_bh_enable();
1623 
1624 	lock_map_release(&trans->sync_cmd_lockdep_map);
1625 
1626 	return IRQ_HANDLED;
1627 }
1628 
1629 /*
1630  * iwl_pcie_irq_handle_error - called for HW or SW error interrupt from card
1631  */
1632 static void iwl_pcie_irq_handle_error(struct iwl_trans *trans)
1633 {
1634 	int i;
1635 
1636 	/* W/A for WiFi/WiMAX coex and WiMAX own the RF */
1637 	if (trans->cfg->internal_wimax_coex &&
1638 	    !trans->cfg->apmg_not_supported &&
1639 	    (!(iwl_read_prph(trans, APMG_CLK_CTRL_REG) &
1640 			     APMS_CLK_VAL_MRB_FUNC_MODE) ||
1641 	     (iwl_read_prph(trans, APMG_PS_CTRL_REG) &
1642 			    APMG_PS_CTRL_VAL_RESET_REQ))) {
1643 		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1644 		iwl_op_mode_wimax_active(trans->op_mode);
1645 		wake_up(&trans->wait_command_queue);
1646 		return;
1647 	}
1648 
1649 	for (i = 0; i < trans->trans_cfg->base_params->num_of_queues; i++) {
1650 		if (!trans->txqs.txq[i])
1651 			continue;
1652 		del_timer(&trans->txqs.txq[i]->stuck_timer);
1653 	}
1654 
1655 	/* The STATUS_FW_ERROR bit is set in this function. This must happen
1656 	 * before we wake up the command caller, to ensure a proper cleanup. */
1657 	iwl_trans_fw_error(trans, false);
1658 
1659 	clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1660 	wake_up(&trans->wait_command_queue);
1661 }
1662 
1663 static u32 iwl_pcie_int_cause_non_ict(struct iwl_trans *trans)
1664 {
1665 	u32 inta;
1666 
1667 	lockdep_assert_held(&IWL_TRANS_GET_PCIE_TRANS(trans)->irq_lock);
1668 
1669 	trace_iwlwifi_dev_irq(trans->dev);
1670 
1671 	/* Discover which interrupts are active/pending */
1672 	inta = iwl_read32(trans, CSR_INT);
1673 
1674 	/* the thread will service interrupts and re-enable them */
1675 	return inta;
1676 }
1677 
1678 /* a device (PCI-E) page is 4096 bytes long */
1679 #define ICT_SHIFT	12
1680 #define ICT_SIZE	(1 << ICT_SHIFT)
1681 #define ICT_COUNT	(ICT_SIZE / sizeof(u32))
1682 
1683 /* interrupt handler using ict table, with this interrupt driver will
1684  * stop using INTA register to get device's interrupt, reading this register
1685  * is expensive, device will write interrupts in ICT dram table, increment
1686  * index then will fire interrupt to driver, driver will OR all ICT table
1687  * entries from current index up to table entry with 0 value. the result is
1688  * the interrupt we need to service, driver will set the entries back to 0 and
1689  * set index.
1690  */
1691 static u32 iwl_pcie_int_cause_ict(struct iwl_trans *trans)
1692 {
1693 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1694 	u32 inta;
1695 	u32 val = 0;
1696 	u32 read;
1697 
1698 	trace_iwlwifi_dev_irq(trans->dev);
1699 
1700 	/* Ignore interrupt if there's nothing in NIC to service.
1701 	 * This may be due to IRQ shared with another device,
1702 	 * or due to sporadic interrupts thrown from our NIC. */
1703 	read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1704 	trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index, read);
1705 	if (!read)
1706 		return 0;
1707 
1708 	/*
1709 	 * Collect all entries up to the first 0, starting from ict_index;
1710 	 * note we already read at ict_index.
1711 	 */
1712 	do {
1713 		val |= read;
1714 		IWL_DEBUG_ISR(trans, "ICT index %d value 0x%08X\n",
1715 				trans_pcie->ict_index, read);
1716 		trans_pcie->ict_tbl[trans_pcie->ict_index] = 0;
1717 		trans_pcie->ict_index =
1718 			((trans_pcie->ict_index + 1) & (ICT_COUNT - 1));
1719 
1720 		read = le32_to_cpu(trans_pcie->ict_tbl[trans_pcie->ict_index]);
1721 		trace_iwlwifi_dev_ict_read(trans->dev, trans_pcie->ict_index,
1722 					   read);
1723 	} while (read);
1724 
1725 	/* We should not get this value, just ignore it. */
1726 	if (val == 0xffffffff)
1727 		val = 0;
1728 
1729 	/*
1730 	 * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit
1731 	 * (bit 15 before shifting it to 31) to clear when using interrupt
1732 	 * coalescing. fortunately, bits 18 and 19 stay set when this happens
1733 	 * so we use them to decide on the real state of the Rx bit.
1734 	 * In order words, bit 15 is set if bit 18 or bit 19 are set.
1735 	 */
1736 	if (val & 0xC0000)
1737 		val |= 0x8000;
1738 
1739 	inta = (0xff & val) | ((0xff00 & val) << 16);
1740 	return inta;
1741 }
1742 
1743 void iwl_pcie_handle_rfkill_irq(struct iwl_trans *trans)
1744 {
1745 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1746 	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1747 	bool hw_rfkill, prev, report;
1748 
1749 	mutex_lock(&trans_pcie->mutex);
1750 	prev = test_bit(STATUS_RFKILL_OPMODE, &trans->status);
1751 	hw_rfkill = iwl_is_rfkill_set(trans);
1752 	if (hw_rfkill) {
1753 		set_bit(STATUS_RFKILL_OPMODE, &trans->status);
1754 		set_bit(STATUS_RFKILL_HW, &trans->status);
1755 	}
1756 	if (trans_pcie->opmode_down)
1757 		report = hw_rfkill;
1758 	else
1759 		report = test_bit(STATUS_RFKILL_OPMODE, &trans->status);
1760 
1761 	IWL_WARN(trans, "RF_KILL bit toggled to %s.\n",
1762 		 hw_rfkill ? "disable radio" : "enable radio");
1763 
1764 	isr_stats->rfkill++;
1765 
1766 	if (prev != report)
1767 		iwl_trans_pcie_rf_kill(trans, report);
1768 	mutex_unlock(&trans_pcie->mutex);
1769 
1770 	if (hw_rfkill) {
1771 		if (test_and_clear_bit(STATUS_SYNC_HCMD_ACTIVE,
1772 				       &trans->status))
1773 			IWL_DEBUG_RF_KILL(trans,
1774 					  "Rfkill while SYNC HCMD in flight\n");
1775 		wake_up(&trans->wait_command_queue);
1776 	} else {
1777 		clear_bit(STATUS_RFKILL_HW, &trans->status);
1778 		if (trans_pcie->opmode_down)
1779 			clear_bit(STATUS_RFKILL_OPMODE, &trans->status);
1780 	}
1781 }
1782 
1783 irqreturn_t iwl_pcie_irq_handler(int irq, void *dev_id)
1784 {
1785 	struct iwl_trans *trans = dev_id;
1786 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1787 	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
1788 	u32 inta = 0;
1789 	u32 handled = 0;
1790 	bool polling = false;
1791 
1792 	lock_map_acquire(&trans->sync_cmd_lockdep_map);
1793 
1794 	spin_lock_bh(&trans_pcie->irq_lock);
1795 
1796 	/* dram interrupt table not set yet,
1797 	 * use legacy interrupt.
1798 	 */
1799 	if (likely(trans_pcie->use_ict))
1800 		inta = iwl_pcie_int_cause_ict(trans);
1801 	else
1802 		inta = iwl_pcie_int_cause_non_ict(trans);
1803 
1804 	if (iwl_have_debug_level(IWL_DL_ISR)) {
1805 		IWL_DEBUG_ISR(trans,
1806 			      "ISR inta 0x%08x, enabled 0x%08x(sw), enabled(hw) 0x%08x, fh 0x%08x\n",
1807 			      inta, trans_pcie->inta_mask,
1808 			      iwl_read32(trans, CSR_INT_MASK),
1809 			      iwl_read32(trans, CSR_FH_INT_STATUS));
1810 		if (inta & (~trans_pcie->inta_mask))
1811 			IWL_DEBUG_ISR(trans,
1812 				      "We got a masked interrupt (0x%08x)\n",
1813 				      inta & (~trans_pcie->inta_mask));
1814 	}
1815 
1816 	inta &= trans_pcie->inta_mask;
1817 
1818 	/*
1819 	 * Ignore interrupt if there's nothing in NIC to service.
1820 	 * This may be due to IRQ shared with another device,
1821 	 * or due to sporadic interrupts thrown from our NIC.
1822 	 */
1823 	if (unlikely(!inta)) {
1824 		IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
1825 		/*
1826 		 * Re-enable interrupts here since we don't
1827 		 * have anything to service
1828 		 */
1829 		if (test_bit(STATUS_INT_ENABLED, &trans->status))
1830 			_iwl_enable_interrupts(trans);
1831 		spin_unlock_bh(&trans_pcie->irq_lock);
1832 		lock_map_release(&trans->sync_cmd_lockdep_map);
1833 		return IRQ_NONE;
1834 	}
1835 
1836 	if (unlikely(inta == 0xFFFFFFFF || (inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
1837 		/*
1838 		 * Hardware disappeared. It might have
1839 		 * already raised an interrupt.
1840 		 */
1841 		IWL_WARN(trans, "HARDWARE GONE?? INTA == 0x%08x\n", inta);
1842 		spin_unlock_bh(&trans_pcie->irq_lock);
1843 		goto out;
1844 	}
1845 
1846 	/* Ack/clear/reset pending uCode interrupts.
1847 	 * Note:  Some bits in CSR_INT are "OR" of bits in CSR_FH_INT_STATUS,
1848 	 */
1849 	/* There is a hardware bug in the interrupt mask function that some
1850 	 * interrupts (i.e. CSR_INT_BIT_SCD) can still be generated even if
1851 	 * they are disabled in the CSR_INT_MASK register. Furthermore the
1852 	 * ICT interrupt handling mechanism has another bug that might cause
1853 	 * these unmasked interrupts fail to be detected. We workaround the
1854 	 * hardware bugs here by ACKing all the possible interrupts so that
1855 	 * interrupt coalescing can still be achieved.
1856 	 */
1857 	iwl_write32(trans, CSR_INT, inta | ~trans_pcie->inta_mask);
1858 
1859 	if (iwl_have_debug_level(IWL_DL_ISR))
1860 		IWL_DEBUG_ISR(trans, "inta 0x%08x, enabled 0x%08x\n",
1861 			      inta, iwl_read32(trans, CSR_INT_MASK));
1862 
1863 	spin_unlock_bh(&trans_pcie->irq_lock);
1864 
1865 	/* Now service all interrupt bits discovered above. */
1866 	if (inta & CSR_INT_BIT_HW_ERR) {
1867 		IWL_ERR(trans, "Hardware error detected.  Restarting.\n");
1868 
1869 		/* Tell the device to stop sending interrupts */
1870 		iwl_disable_interrupts(trans);
1871 
1872 		isr_stats->hw++;
1873 		iwl_pcie_irq_handle_error(trans);
1874 
1875 		handled |= CSR_INT_BIT_HW_ERR;
1876 
1877 		goto out;
1878 	}
1879 
1880 	/* NIC fires this, but we don't use it, redundant with WAKEUP */
1881 	if (inta & CSR_INT_BIT_SCD) {
1882 		IWL_DEBUG_ISR(trans,
1883 			      "Scheduler finished to transmit the frame/frames.\n");
1884 		isr_stats->sch++;
1885 	}
1886 
1887 	/* Alive notification via Rx interrupt will do the real work */
1888 	if (inta & CSR_INT_BIT_ALIVE) {
1889 		IWL_DEBUG_ISR(trans, "Alive interrupt\n");
1890 		isr_stats->alive++;
1891 		if (trans->trans_cfg->gen2) {
1892 			/*
1893 			 * We can restock, since firmware configured
1894 			 * the RFH
1895 			 */
1896 			iwl_pcie_rxmq_restock(trans, trans_pcie->rxq);
1897 		}
1898 
1899 		handled |= CSR_INT_BIT_ALIVE;
1900 	}
1901 
1902 	/* Safely ignore these bits for debug checks below */
1903 	inta &= ~(CSR_INT_BIT_SCD | CSR_INT_BIT_ALIVE);
1904 
1905 	/* HW RF KILL switch toggled */
1906 	if (inta & CSR_INT_BIT_RF_KILL) {
1907 		iwl_pcie_handle_rfkill_irq(trans);
1908 		handled |= CSR_INT_BIT_RF_KILL;
1909 	}
1910 
1911 	/* Chip got too hot and stopped itself */
1912 	if (inta & CSR_INT_BIT_CT_KILL) {
1913 		IWL_ERR(trans, "Microcode CT kill error detected.\n");
1914 		isr_stats->ctkill++;
1915 		handled |= CSR_INT_BIT_CT_KILL;
1916 	}
1917 
1918 	/* Error detected by uCode */
1919 	if (inta & CSR_INT_BIT_SW_ERR) {
1920 		IWL_ERR(trans, "Microcode SW error detected. "
1921 			" Restarting 0x%X.\n", inta);
1922 		isr_stats->sw++;
1923 		iwl_pcie_irq_handle_error(trans);
1924 		handled |= CSR_INT_BIT_SW_ERR;
1925 	}
1926 
1927 	/* uCode wakes up after power-down sleep */
1928 	if (inta & CSR_INT_BIT_WAKEUP) {
1929 		IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
1930 		iwl_pcie_rxq_check_wrptr(trans);
1931 		iwl_pcie_txq_check_wrptrs(trans);
1932 
1933 		isr_stats->wakeup++;
1934 
1935 		handled |= CSR_INT_BIT_WAKEUP;
1936 	}
1937 
1938 	/* All uCode command responses, including Tx command responses,
1939 	 * Rx "responses" (frame-received notification), and other
1940 	 * notifications from uCode come through here*/
1941 	if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX |
1942 		    CSR_INT_BIT_RX_PERIODIC)) {
1943 		IWL_DEBUG_ISR(trans, "Rx interrupt\n");
1944 		if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX)) {
1945 			handled |= (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX);
1946 			iwl_write32(trans, CSR_FH_INT_STATUS,
1947 					CSR_FH_INT_RX_MASK);
1948 		}
1949 		if (inta & CSR_INT_BIT_RX_PERIODIC) {
1950 			handled |= CSR_INT_BIT_RX_PERIODIC;
1951 			iwl_write32(trans,
1952 				CSR_INT, CSR_INT_BIT_RX_PERIODIC);
1953 		}
1954 		/* Sending RX interrupt require many steps to be done in the
1955 		 * the device:
1956 		 * 1- write interrupt to current index in ICT table.
1957 		 * 2- dma RX frame.
1958 		 * 3- update RX shared data to indicate last write index.
1959 		 * 4- send interrupt.
1960 		 * This could lead to RX race, driver could receive RX interrupt
1961 		 * but the shared data changes does not reflect this;
1962 		 * periodic interrupt will detect any dangling Rx activity.
1963 		 */
1964 
1965 		/* Disable periodic interrupt; we use it as just a one-shot. */
1966 		iwl_write8(trans, CSR_INT_PERIODIC_REG,
1967 			    CSR_INT_PERIODIC_DIS);
1968 
1969 		/*
1970 		 * Enable periodic interrupt in 8 msec only if we received
1971 		 * real RX interrupt (instead of just periodic int), to catch
1972 		 * any dangling Rx interrupt.  If it was just the periodic
1973 		 * interrupt, there was no dangling Rx activity, and no need
1974 		 * to extend the periodic interrupt; one-shot is enough.
1975 		 */
1976 		if (inta & (CSR_INT_BIT_FH_RX | CSR_INT_BIT_SW_RX))
1977 			iwl_write8(trans, CSR_INT_PERIODIC_REG,
1978 				   CSR_INT_PERIODIC_ENA);
1979 
1980 		isr_stats->rx++;
1981 
1982 		local_bh_disable();
1983 		if (napi_schedule_prep(&trans_pcie->rxq[0].napi)) {
1984 			polling = true;
1985 			__napi_schedule(&trans_pcie->rxq[0].napi);
1986 		}
1987 		local_bh_enable();
1988 	}
1989 
1990 	/* This "Tx" DMA channel is used only for loading uCode */
1991 	if (inta & CSR_INT_BIT_FH_TX) {
1992 		iwl_write32(trans, CSR_FH_INT_STATUS, CSR_FH_INT_TX_MASK);
1993 		IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
1994 		isr_stats->tx++;
1995 		handled |= CSR_INT_BIT_FH_TX;
1996 		/* Wake up uCode load routine, now that load is complete */
1997 		trans_pcie->ucode_write_complete = true;
1998 		wake_up(&trans_pcie->ucode_write_waitq);
1999 	}
2000 
2001 	if (inta & ~handled) {
2002 		IWL_ERR(trans, "Unhandled INTA bits 0x%08x\n", inta & ~handled);
2003 		isr_stats->unhandled++;
2004 	}
2005 
2006 	if (inta & ~(trans_pcie->inta_mask)) {
2007 		IWL_WARN(trans, "Disabled INTA bits 0x%08x were pending\n",
2008 			 inta & ~trans_pcie->inta_mask);
2009 	}
2010 
2011 	if (!polling) {
2012 		spin_lock_bh(&trans_pcie->irq_lock);
2013 		/* only Re-enable all interrupt if disabled by irq */
2014 		if (test_bit(STATUS_INT_ENABLED, &trans->status))
2015 			_iwl_enable_interrupts(trans);
2016 		/* we are loading the firmware, enable FH_TX interrupt only */
2017 		else if (handled & CSR_INT_BIT_FH_TX)
2018 			iwl_enable_fw_load_int(trans);
2019 		/* Re-enable RF_KILL if it occurred */
2020 		else if (handled & CSR_INT_BIT_RF_KILL)
2021 			iwl_enable_rfkill_int(trans);
2022 		/* Re-enable the ALIVE / Rx interrupt if it occurred */
2023 		else if (handled & (CSR_INT_BIT_ALIVE | CSR_INT_BIT_FH_RX))
2024 			iwl_enable_fw_load_int_ctx_info(trans);
2025 		spin_unlock_bh(&trans_pcie->irq_lock);
2026 	}
2027 
2028 out:
2029 	lock_map_release(&trans->sync_cmd_lockdep_map);
2030 	return IRQ_HANDLED;
2031 }
2032 
2033 /******************************************************************************
2034  *
2035  * ICT functions
2036  *
2037  ******************************************************************************/
2038 
2039 /* Free dram table */
2040 void iwl_pcie_free_ict(struct iwl_trans *trans)
2041 {
2042 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2043 
2044 	if (trans_pcie->ict_tbl) {
2045 		dma_free_coherent(trans->dev, ICT_SIZE,
2046 				  trans_pcie->ict_tbl,
2047 				  trans_pcie->ict_tbl_dma);
2048 		trans_pcie->ict_tbl = NULL;
2049 		trans_pcie->ict_tbl_dma = 0;
2050 	}
2051 }
2052 
2053 /*
2054  * allocate dram shared table, it is an aligned memory
2055  * block of ICT_SIZE.
2056  * also reset all data related to ICT table interrupt.
2057  */
2058 int iwl_pcie_alloc_ict(struct iwl_trans *trans)
2059 {
2060 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2061 
2062 	trans_pcie->ict_tbl =
2063 		dma_alloc_coherent(trans->dev, ICT_SIZE,
2064 				   &trans_pcie->ict_tbl_dma, GFP_KERNEL);
2065 	if (!trans_pcie->ict_tbl)
2066 		return -ENOMEM;
2067 
2068 	/* just an API sanity check ... it is guaranteed to be aligned */
2069 	if (WARN_ON(trans_pcie->ict_tbl_dma & (ICT_SIZE - 1))) {
2070 		iwl_pcie_free_ict(trans);
2071 		return -EINVAL;
2072 	}
2073 
2074 	return 0;
2075 }
2076 
2077 /* Device is going up inform it about using ICT interrupt table,
2078  * also we need to tell the driver to start using ICT interrupt.
2079  */
2080 void iwl_pcie_reset_ict(struct iwl_trans *trans)
2081 {
2082 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2083 	u32 val;
2084 
2085 	if (!trans_pcie->ict_tbl)
2086 		return;
2087 
2088 	spin_lock_bh(&trans_pcie->irq_lock);
2089 	_iwl_disable_interrupts(trans);
2090 
2091 	memset(trans_pcie->ict_tbl, 0, ICT_SIZE);
2092 
2093 	val = trans_pcie->ict_tbl_dma >> ICT_SHIFT;
2094 
2095 	val |= CSR_DRAM_INT_TBL_ENABLE |
2096 	       CSR_DRAM_INIT_TBL_WRAP_CHECK |
2097 	       CSR_DRAM_INIT_TBL_WRITE_POINTER;
2098 
2099 	IWL_DEBUG_ISR(trans, "CSR_DRAM_INT_TBL_REG =0x%x\n", val);
2100 
2101 	iwl_write32(trans, CSR_DRAM_INT_TBL_REG, val);
2102 	trans_pcie->use_ict = true;
2103 	trans_pcie->ict_index = 0;
2104 	iwl_write32(trans, CSR_INT, trans_pcie->inta_mask);
2105 	_iwl_enable_interrupts(trans);
2106 	spin_unlock_bh(&trans_pcie->irq_lock);
2107 }
2108 
2109 /* Device is going down disable ict interrupt usage */
2110 void iwl_pcie_disable_ict(struct iwl_trans *trans)
2111 {
2112 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2113 
2114 	spin_lock_bh(&trans_pcie->irq_lock);
2115 	trans_pcie->use_ict = false;
2116 	spin_unlock_bh(&trans_pcie->irq_lock);
2117 }
2118 
2119 irqreturn_t iwl_pcie_isr(int irq, void *data)
2120 {
2121 	struct iwl_trans *trans = data;
2122 
2123 	if (!trans)
2124 		return IRQ_NONE;
2125 
2126 	/* Disable (but don't clear!) interrupts here to avoid
2127 	 * back-to-back ISRs and sporadic interrupts from our NIC.
2128 	 * If we have something to service, the tasklet will re-enable ints.
2129 	 * If we *don't* have something, we'll re-enable before leaving here.
2130 	 */
2131 	iwl_write32(trans, CSR_INT_MASK, 0x00000000);
2132 
2133 	return IRQ_WAKE_THREAD;
2134 }
2135 
2136 irqreturn_t iwl_pcie_msix_isr(int irq, void *data)
2137 {
2138 	return IRQ_WAKE_THREAD;
2139 }
2140 
2141 irqreturn_t iwl_pcie_irq_msix_handler(int irq, void *dev_id)
2142 {
2143 	struct msix_entry *entry = dev_id;
2144 	struct iwl_trans_pcie *trans_pcie = iwl_pcie_get_trans_pcie(entry);
2145 	struct iwl_trans *trans = trans_pcie->trans;
2146 	struct isr_statistics *isr_stats = &trans_pcie->isr_stats;
2147 	u32 inta_fh_msk = ~MSIX_FH_INT_CAUSES_DATA_QUEUE;
2148 	u32 inta_fh, inta_hw;
2149 	bool polling = false;
2150 	bool sw_err;
2151 
2152 	if (trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_NON_RX)
2153 		inta_fh_msk |= MSIX_FH_INT_CAUSES_Q0;
2154 
2155 	if (trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS)
2156 		inta_fh_msk |= MSIX_FH_INT_CAUSES_Q1;
2157 
2158 	lock_map_acquire(&trans->sync_cmd_lockdep_map);
2159 
2160 	spin_lock_bh(&trans_pcie->irq_lock);
2161 	inta_fh = iwl_read32(trans, CSR_MSIX_FH_INT_CAUSES_AD);
2162 	inta_hw = iwl_read32(trans, CSR_MSIX_HW_INT_CAUSES_AD);
2163 	/*
2164 	 * Clear causes registers to avoid being handling the same cause.
2165 	 */
2166 	iwl_write32(trans, CSR_MSIX_FH_INT_CAUSES_AD, inta_fh & inta_fh_msk);
2167 	iwl_write32(trans, CSR_MSIX_HW_INT_CAUSES_AD, inta_hw);
2168 	spin_unlock_bh(&trans_pcie->irq_lock);
2169 
2170 	trace_iwlwifi_dev_irq_msix(trans->dev, entry, true, inta_fh, inta_hw);
2171 
2172 	if (unlikely(!(inta_fh | inta_hw))) {
2173 		IWL_DEBUG_ISR(trans, "Ignore interrupt, inta == 0\n");
2174 		lock_map_release(&trans->sync_cmd_lockdep_map);
2175 		return IRQ_NONE;
2176 	}
2177 
2178 	if (iwl_have_debug_level(IWL_DL_ISR)) {
2179 		IWL_DEBUG_ISR(trans,
2180 			      "ISR[%d] inta_fh 0x%08x, enabled (sw) 0x%08x (hw) 0x%08x\n",
2181 			      entry->entry, inta_fh, trans_pcie->fh_mask,
2182 			      iwl_read32(trans, CSR_MSIX_FH_INT_MASK_AD));
2183 		if (inta_fh & ~trans_pcie->fh_mask)
2184 			IWL_DEBUG_ISR(trans,
2185 				      "We got a masked interrupt (0x%08x)\n",
2186 				      inta_fh & ~trans_pcie->fh_mask);
2187 	}
2188 
2189 	inta_fh &= trans_pcie->fh_mask;
2190 
2191 	if ((trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_NON_RX) &&
2192 	    inta_fh & MSIX_FH_INT_CAUSES_Q0) {
2193 		local_bh_disable();
2194 		if (napi_schedule_prep(&trans_pcie->rxq[0].napi)) {
2195 			polling = true;
2196 			__napi_schedule(&trans_pcie->rxq[0].napi);
2197 		}
2198 		local_bh_enable();
2199 	}
2200 
2201 	if ((trans_pcie->shared_vec_mask & IWL_SHARED_IRQ_FIRST_RSS) &&
2202 	    inta_fh & MSIX_FH_INT_CAUSES_Q1) {
2203 		local_bh_disable();
2204 		if (napi_schedule_prep(&trans_pcie->rxq[1].napi)) {
2205 			polling = true;
2206 			__napi_schedule(&trans_pcie->rxq[1].napi);
2207 		}
2208 		local_bh_enable();
2209 	}
2210 
2211 	/* This "Tx" DMA channel is used only for loading uCode */
2212 	if (inta_fh & MSIX_FH_INT_CAUSES_D2S_CH0_NUM) {
2213 		IWL_DEBUG_ISR(trans, "uCode load interrupt\n");
2214 		isr_stats->tx++;
2215 		/*
2216 		 * Wake up uCode load routine,
2217 		 * now that load is complete
2218 		 */
2219 		trans_pcie->ucode_write_complete = true;
2220 		wake_up(&trans_pcie->ucode_write_waitq);
2221 	}
2222 
2223 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_BZ)
2224 		sw_err = inta_hw & MSIX_HW_INT_CAUSES_REG_SW_ERR_BZ;
2225 	else
2226 		sw_err = inta_hw & MSIX_HW_INT_CAUSES_REG_SW_ERR;
2227 
2228 	/* Error detected by uCode */
2229 	if ((inta_fh & MSIX_FH_INT_CAUSES_FH_ERR) || sw_err) {
2230 		IWL_ERR(trans,
2231 			"Microcode SW error detected. Restarting 0x%X.\n",
2232 			inta_fh);
2233 		isr_stats->sw++;
2234 		/* during FW reset flow report errors from there */
2235 		if (trans_pcie->fw_reset_state == FW_RESET_REQUESTED) {
2236 			trans_pcie->fw_reset_state = FW_RESET_ERROR;
2237 			wake_up(&trans_pcie->fw_reset_waitq);
2238 		} else {
2239 			iwl_pcie_irq_handle_error(trans);
2240 		}
2241 	}
2242 
2243 	/* After checking FH register check HW register */
2244 	if (iwl_have_debug_level(IWL_DL_ISR)) {
2245 		IWL_DEBUG_ISR(trans,
2246 			      "ISR[%d] inta_hw 0x%08x, enabled (sw) 0x%08x (hw) 0x%08x\n",
2247 			      entry->entry, inta_hw, trans_pcie->hw_mask,
2248 			      iwl_read32(trans, CSR_MSIX_HW_INT_MASK_AD));
2249 		if (inta_hw & ~trans_pcie->hw_mask)
2250 			IWL_DEBUG_ISR(trans,
2251 				      "We got a masked interrupt 0x%08x\n",
2252 				      inta_hw & ~trans_pcie->hw_mask);
2253 	}
2254 
2255 	inta_hw &= trans_pcie->hw_mask;
2256 
2257 	/* Alive notification via Rx interrupt will do the real work */
2258 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_ALIVE) {
2259 		IWL_DEBUG_ISR(trans, "Alive interrupt\n");
2260 		isr_stats->alive++;
2261 		if (trans->trans_cfg->gen2) {
2262 			/* We can restock, since firmware configured the RFH */
2263 			iwl_pcie_rxmq_restock(trans, trans_pcie->rxq);
2264 		}
2265 	}
2266 
2267 	/*
2268 	 * In some rare cases when the HW is in a bad state, we may
2269 	 * get this interrupt too early, when prph_info is still NULL.
2270 	 * So make sure that it's not NULL to prevent crashing.
2271 	 */
2272 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_WAKEUP && trans_pcie->prph_info) {
2273 		u32 sleep_notif =
2274 			le32_to_cpu(trans_pcie->prph_info->sleep_notif);
2275 		if (sleep_notif == IWL_D3_SLEEP_STATUS_SUSPEND ||
2276 		    sleep_notif == IWL_D3_SLEEP_STATUS_RESUME) {
2277 			IWL_DEBUG_ISR(trans,
2278 				      "Sx interrupt: sleep notification = 0x%x\n",
2279 				      sleep_notif);
2280 			trans_pcie->sx_complete = true;
2281 			wake_up(&trans_pcie->sx_waitq);
2282 		} else {
2283 			/* uCode wakes up after power-down sleep */
2284 			IWL_DEBUG_ISR(trans, "Wakeup interrupt\n");
2285 			iwl_pcie_rxq_check_wrptr(trans);
2286 			iwl_pcie_txq_check_wrptrs(trans);
2287 
2288 			isr_stats->wakeup++;
2289 		}
2290 	}
2291 
2292 	/* Chip got too hot and stopped itself */
2293 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_CT_KILL) {
2294 		IWL_ERR(trans, "Microcode CT kill error detected.\n");
2295 		isr_stats->ctkill++;
2296 	}
2297 
2298 	/* HW RF KILL switch toggled */
2299 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_RF_KILL)
2300 		iwl_pcie_handle_rfkill_irq(trans);
2301 
2302 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_HW_ERR) {
2303 		IWL_ERR(trans,
2304 			"Hardware error detected. Restarting.\n");
2305 
2306 		isr_stats->hw++;
2307 		trans->dbg.hw_error = true;
2308 		iwl_pcie_irq_handle_error(trans);
2309 	}
2310 
2311 	if (inta_hw & MSIX_HW_INT_CAUSES_REG_RESET_DONE) {
2312 		IWL_DEBUG_ISR(trans, "Reset flow completed\n");
2313 		trans_pcie->fw_reset_state = FW_RESET_OK;
2314 		wake_up(&trans_pcie->fw_reset_waitq);
2315 	}
2316 
2317 	if (!polling)
2318 		iwl_pcie_clear_irq(trans, entry->entry);
2319 
2320 	lock_map_release(&trans->sync_cmd_lockdep_map);
2321 
2322 	return IRQ_HANDLED;
2323 }
2324