1 /******************************************************************************
2  *
3  * Copyright(c) 2003 - 2014 Intel Corporation. All rights reserved.
4  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
5  * Copyright(c) 2016 Intel Deutschland GmbH
6  *
7  * Portions of this file are derived from the ipw3945 project, as well
8  * as portions of the ieee80211 subsystem header files.
9  *
10  * This program is free software; you can redistribute it and/or modify it
11  * under the terms of version 2 of the GNU General Public License as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  *
19  * You should have received a copy of the GNU General Public License along with
20  * this program; if not, write to the Free Software Foundation, Inc.,
21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
22  *
23  * The full GNU General Public License is included in this distribution in the
24  * file called LICENSE.
25  *
26  * Contact Information:
27  *  Intel Linux Wireless <linuxwifi@intel.com>
28  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
29  *
30  *****************************************************************************/
31 #include <linux/etherdevice.h>
32 #include <linux/ieee80211.h>
33 #include <linux/slab.h>
34 #include <linux/sched.h>
35 #include <linux/pm_runtime.h>
36 #include <net/ip6_checksum.h>
37 #include <net/tso.h>
38 
39 #include "iwl-debug.h"
40 #include "iwl-csr.h"
41 #include "iwl-prph.h"
42 #include "iwl-io.h"
43 #include "iwl-scd.h"
44 #include "iwl-op-mode.h"
45 #include "internal.h"
46 /* FIXME: need to abstract out TX command (once we know what it looks like) */
47 #include "dvm/commands.h"
48 
49 #define IWL_TX_CRC_SIZE 4
50 #define IWL_TX_DELIMITER_SIZE 4
51 
52 /*************** DMA-QUEUE-GENERAL-FUNCTIONS  *****
53  * DMA services
54  *
55  * Theory of operation
56  *
57  * A Tx or Rx queue resides in host DRAM, and is comprised of a circular buffer
58  * of buffer descriptors, each of which points to one or more data buffers for
59  * the device to read from or fill.  Driver and device exchange status of each
60  * queue via "read" and "write" pointers.  Driver keeps minimum of 2 empty
61  * entries in each circular buffer, to protect against confusing empty and full
62  * queue states.
63  *
64  * The device reads or writes the data in the queues via the device's several
65  * DMA/FIFO channels.  Each queue is mapped to a single DMA channel.
66  *
67  * For Tx queue, there are low mark and high mark limits. If, after queuing
68  * the packet for Tx, free space become < low mark, Tx queue stopped. When
69  * reclaiming packets (on 'tx done IRQ), if free space become > high mark,
70  * Tx queue resumed.
71  *
72  ***************************************************/
73 
74 static int iwl_queue_space(const struct iwl_txq *q)
75 {
76 	unsigned int max;
77 	unsigned int used;
78 
79 	/*
80 	 * To avoid ambiguity between empty and completely full queues, there
81 	 * should always be less than TFD_QUEUE_SIZE_MAX elements in the queue.
82 	 * If q->n_window is smaller than TFD_QUEUE_SIZE_MAX, there is no need
83 	 * to reserve any queue entries for this purpose.
84 	 */
85 	if (q->n_window < TFD_QUEUE_SIZE_MAX)
86 		max = q->n_window;
87 	else
88 		max = TFD_QUEUE_SIZE_MAX - 1;
89 
90 	/*
91 	 * TFD_QUEUE_SIZE_MAX is a power of 2, so the following is equivalent to
92 	 * modulo by TFD_QUEUE_SIZE_MAX and is well defined.
93 	 */
94 	used = (q->write_ptr - q->read_ptr) & (TFD_QUEUE_SIZE_MAX - 1);
95 
96 	if (WARN_ON(used > max))
97 		return 0;
98 
99 	return max - used;
100 }
101 
102 /*
103  * iwl_queue_init - Initialize queue's high/low-water and read/write indexes
104  */
105 static int iwl_queue_init(struct iwl_txq *q, int slots_num, u32 id)
106 {
107 	q->n_window = slots_num;
108 	q->id = id;
109 
110 	/* slots_num must be power-of-two size, otherwise
111 	 * get_cmd_index is broken. */
112 	if (WARN_ON(!is_power_of_2(slots_num)))
113 		return -EINVAL;
114 
115 	q->low_mark = q->n_window / 4;
116 	if (q->low_mark < 4)
117 		q->low_mark = 4;
118 
119 	q->high_mark = q->n_window / 8;
120 	if (q->high_mark < 2)
121 		q->high_mark = 2;
122 
123 	q->write_ptr = 0;
124 	q->read_ptr = 0;
125 
126 	return 0;
127 }
128 
129 static int iwl_pcie_alloc_dma_ptr(struct iwl_trans *trans,
130 				  struct iwl_dma_ptr *ptr, size_t size)
131 {
132 	if (WARN_ON(ptr->addr))
133 		return -EINVAL;
134 
135 	ptr->addr = dma_alloc_coherent(trans->dev, size,
136 				       &ptr->dma, GFP_KERNEL);
137 	if (!ptr->addr)
138 		return -ENOMEM;
139 	ptr->size = size;
140 	return 0;
141 }
142 
143 static void iwl_pcie_free_dma_ptr(struct iwl_trans *trans,
144 				  struct iwl_dma_ptr *ptr)
145 {
146 	if (unlikely(!ptr->addr))
147 		return;
148 
149 	dma_free_coherent(trans->dev, ptr->size, ptr->addr, ptr->dma);
150 	memset(ptr, 0, sizeof(*ptr));
151 }
152 
153 static void iwl_pcie_txq_stuck_timer(unsigned long data)
154 {
155 	struct iwl_txq *txq = (void *)data;
156 	struct iwl_trans_pcie *trans_pcie = txq->trans_pcie;
157 	struct iwl_trans *trans = iwl_trans_pcie_get_trans(trans_pcie);
158 
159 	spin_lock(&txq->lock);
160 	/* check if triggered erroneously */
161 	if (txq->read_ptr == txq->write_ptr) {
162 		spin_unlock(&txq->lock);
163 		return;
164 	}
165 	spin_unlock(&txq->lock);
166 
167 	IWL_ERR(trans, "Queue %d stuck for %u ms.\n", txq->id,
168 		jiffies_to_msecs(txq->wd_timeout));
169 
170 	iwl_trans_pcie_log_scd_error(trans, txq);
171 
172 	iwl_force_nmi(trans);
173 }
174 
175 /*
176  * iwl_pcie_txq_update_byte_cnt_tbl - Set up entry in Tx byte-count array
177  */
178 static void iwl_pcie_txq_update_byte_cnt_tbl(struct iwl_trans *trans,
179 					     struct iwl_txq *txq, u16 byte_cnt,
180 					     int num_tbs)
181 {
182 	struct iwlagn_scd_bc_tbl *scd_bc_tbl;
183 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
184 	int write_ptr = txq->write_ptr;
185 	int txq_id = txq->id;
186 	u8 sec_ctl = 0;
187 	u16 len = byte_cnt + IWL_TX_CRC_SIZE + IWL_TX_DELIMITER_SIZE;
188 	__le16 bc_ent;
189 	struct iwl_tx_cmd *tx_cmd =
190 		(void *)txq->entries[txq->write_ptr].cmd->payload;
191 
192 	scd_bc_tbl = trans_pcie->scd_bc_tbls.addr;
193 
194 	sec_ctl = tx_cmd->sec_ctl;
195 
196 	switch (sec_ctl & TX_CMD_SEC_MSK) {
197 	case TX_CMD_SEC_CCM:
198 		len += IEEE80211_CCMP_MIC_LEN;
199 		break;
200 	case TX_CMD_SEC_TKIP:
201 		len += IEEE80211_TKIP_ICV_LEN;
202 		break;
203 	case TX_CMD_SEC_WEP:
204 		len += IEEE80211_WEP_IV_LEN + IEEE80211_WEP_ICV_LEN;
205 		break;
206 	}
207 	if (trans_pcie->bc_table_dword)
208 		len = DIV_ROUND_UP(len, 4);
209 
210 	if (WARN_ON(len > 0xFFF || write_ptr >= TFD_QUEUE_SIZE_MAX))
211 		return;
212 
213 	if (trans->cfg->use_tfh) {
214 		u8 filled_tfd_size = offsetof(struct iwl_tfh_tfd, tbs) +
215 				     num_tbs * sizeof(struct iwl_tfh_tb);
216 		/*
217 		 * filled_tfd_size contains the number of filled bytes in the
218 		 * TFD.
219 		 * Dividing it by 64 will give the number of chunks to fetch
220 		 * to SRAM- 0 for one chunk, 1 for 2 and so on.
221 		 * If, for example, TFD contains only 3 TBs then 32 bytes
222 		 * of the TFD are used, and only one chunk of 64 bytes should
223 		 * be fetched
224 		 */
225 		u8 num_fetch_chunks = DIV_ROUND_UP(filled_tfd_size, 64) - 1;
226 
227 		bc_ent = cpu_to_le16(len | (num_fetch_chunks << 12));
228 	} else {
229 		u8 sta_id = tx_cmd->sta_id;
230 
231 		bc_ent = cpu_to_le16(len | (sta_id << 12));
232 	}
233 
234 	scd_bc_tbl[txq_id].tfd_offset[write_ptr] = bc_ent;
235 
236 	if (write_ptr < TFD_QUEUE_SIZE_BC_DUP)
237 		scd_bc_tbl[txq_id].
238 			tfd_offset[TFD_QUEUE_SIZE_MAX + write_ptr] = bc_ent;
239 }
240 
241 static void iwl_pcie_txq_inval_byte_cnt_tbl(struct iwl_trans *trans,
242 					    struct iwl_txq *txq)
243 {
244 	struct iwl_trans_pcie *trans_pcie =
245 		IWL_TRANS_GET_PCIE_TRANS(trans);
246 	struct iwlagn_scd_bc_tbl *scd_bc_tbl = trans_pcie->scd_bc_tbls.addr;
247 	int txq_id = txq->id;
248 	int read_ptr = txq->read_ptr;
249 	u8 sta_id = 0;
250 	__le16 bc_ent;
251 	struct iwl_tx_cmd *tx_cmd =
252 		(void *)txq->entries[read_ptr].cmd->payload;
253 
254 	WARN_ON(read_ptr >= TFD_QUEUE_SIZE_MAX);
255 
256 	if (txq_id != trans_pcie->cmd_queue)
257 		sta_id = tx_cmd->sta_id;
258 
259 	bc_ent = cpu_to_le16(1 | (sta_id << 12));
260 
261 	scd_bc_tbl[txq_id].tfd_offset[read_ptr] = bc_ent;
262 
263 	if (read_ptr < TFD_QUEUE_SIZE_BC_DUP)
264 		scd_bc_tbl[txq_id].
265 			tfd_offset[TFD_QUEUE_SIZE_MAX + read_ptr] = bc_ent;
266 }
267 
268 /*
269  * iwl_pcie_txq_inc_wr_ptr - Send new write index to hardware
270  */
271 static void iwl_pcie_txq_inc_wr_ptr(struct iwl_trans *trans,
272 				    struct iwl_txq *txq)
273 {
274 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
275 	u32 reg = 0;
276 	int txq_id = txq->id;
277 
278 	lockdep_assert_held(&txq->lock);
279 
280 	/*
281 	 * explicitly wake up the NIC if:
282 	 * 1. shadow registers aren't enabled
283 	 * 2. NIC is woken up for CMD regardless of shadow outside this function
284 	 * 3. there is a chance that the NIC is asleep
285 	 */
286 	if (!trans->cfg->base_params->shadow_reg_enable &&
287 	    txq_id != trans_pcie->cmd_queue &&
288 	    test_bit(STATUS_TPOWER_PMI, &trans->status)) {
289 		/*
290 		 * wake up nic if it's powered down ...
291 		 * uCode will wake up, and interrupt us again, so next
292 		 * time we'll skip this part.
293 		 */
294 		reg = iwl_read32(trans, CSR_UCODE_DRV_GP1);
295 
296 		if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
297 			IWL_DEBUG_INFO(trans, "Tx queue %d requesting wakeup, GP1 = 0x%x\n",
298 				       txq_id, reg);
299 			iwl_set_bit(trans, CSR_GP_CNTRL,
300 				    CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
301 			txq->need_update = true;
302 			return;
303 		}
304 	}
305 
306 	/*
307 	 * if not in power-save mode, uCode will never sleep when we're
308 	 * trying to tx (during RFKILL, we're not trying to tx).
309 	 */
310 	IWL_DEBUG_TX(trans, "Q:%d WR: 0x%x\n", txq_id, txq->write_ptr);
311 	if (!txq->block)
312 		iwl_write32(trans, HBUS_TARG_WRPTR,
313 			    txq->write_ptr | (txq_id << 8));
314 }
315 
316 void iwl_pcie_txq_check_wrptrs(struct iwl_trans *trans)
317 {
318 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
319 	int i;
320 
321 	for (i = 0; i < trans->cfg->base_params->num_of_queues; i++) {
322 		struct iwl_txq *txq = &trans_pcie->txq[i];
323 
324 		spin_lock_bh(&txq->lock);
325 		if (trans_pcie->txq[i].need_update) {
326 			iwl_pcie_txq_inc_wr_ptr(trans, txq);
327 			trans_pcie->txq[i].need_update = false;
328 		}
329 		spin_unlock_bh(&txq->lock);
330 	}
331 }
332 
333 static inline void *iwl_pcie_get_tfd(struct iwl_trans_pcie *trans_pcie,
334 				     struct iwl_txq *txq, int idx)
335 {
336 	return txq->tfds + trans_pcie->tfd_size * idx;
337 }
338 
339 static inline dma_addr_t iwl_pcie_tfd_tb_get_addr(struct iwl_trans *trans,
340 						  void *_tfd, u8 idx)
341 {
342 
343 	if (trans->cfg->use_tfh) {
344 		struct iwl_tfh_tfd *tfd = _tfd;
345 		struct iwl_tfh_tb *tb = &tfd->tbs[idx];
346 
347 		return (dma_addr_t)(le64_to_cpu(tb->addr));
348 	} else {
349 		struct iwl_tfd *tfd = _tfd;
350 		struct iwl_tfd_tb *tb = &tfd->tbs[idx];
351 		dma_addr_t addr = get_unaligned_le32(&tb->lo);
352 		dma_addr_t hi_len;
353 
354 		if (sizeof(dma_addr_t) <= sizeof(u32))
355 			return addr;
356 
357 		hi_len = le16_to_cpu(tb->hi_n_len) & 0xF;
358 
359 		/*
360 		 * shift by 16 twice to avoid warnings on 32-bit
361 		 * (where this code never runs anyway due to the
362 		 * if statement above)
363 		 */
364 		return addr | ((hi_len << 16) << 16);
365 	}
366 }
367 
368 static inline void iwl_pcie_tfd_set_tb(struct iwl_trans *trans, void *tfd,
369 				       u8 idx, dma_addr_t addr, u16 len)
370 {
371 	if (trans->cfg->use_tfh) {
372 		struct iwl_tfh_tfd *tfd_fh = (void *)tfd;
373 		struct iwl_tfh_tb *tb = &tfd_fh->tbs[idx];
374 
375 		put_unaligned_le64(addr, &tb->addr);
376 		tb->tb_len = cpu_to_le16(len);
377 
378 		tfd_fh->num_tbs = cpu_to_le16(idx + 1);
379 	} else {
380 		struct iwl_tfd *tfd_fh = (void *)tfd;
381 		struct iwl_tfd_tb *tb = &tfd_fh->tbs[idx];
382 
383 		u16 hi_n_len = len << 4;
384 
385 		put_unaligned_le32(addr, &tb->lo);
386 		if (sizeof(dma_addr_t) > sizeof(u32))
387 			hi_n_len |= ((addr >> 16) >> 16) & 0xF;
388 
389 		tb->hi_n_len = cpu_to_le16(hi_n_len);
390 
391 		tfd_fh->num_tbs = idx + 1;
392 	}
393 }
394 
395 static inline u8 iwl_pcie_tfd_get_num_tbs(struct iwl_trans *trans, void *_tfd)
396 {
397 	if (trans->cfg->use_tfh) {
398 		struct iwl_tfh_tfd *tfd = _tfd;
399 
400 		return le16_to_cpu(tfd->num_tbs) & 0x1f;
401 	} else {
402 		struct iwl_tfd *tfd = _tfd;
403 
404 		return tfd->num_tbs & 0x1f;
405 	}
406 }
407 
408 static void iwl_pcie_tfd_unmap(struct iwl_trans *trans,
409 			       struct iwl_cmd_meta *meta,
410 			       struct iwl_txq *txq, int index)
411 {
412 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
413 	int i, num_tbs;
414 	void *tfd = iwl_pcie_get_tfd(trans_pcie, txq, index);
415 
416 	/* Sanity check on number of chunks */
417 	num_tbs = iwl_pcie_tfd_get_num_tbs(trans, tfd);
418 
419 	if (num_tbs >= trans_pcie->max_tbs) {
420 		IWL_ERR(trans, "Too many chunks: %i\n", num_tbs);
421 		/* @todo issue fatal error, it is quite serious situation */
422 		return;
423 	}
424 
425 	/* first TB is never freed - it's the bidirectional DMA data */
426 
427 	for (i = 1; i < num_tbs; i++) {
428 		if (meta->tbs & BIT(i))
429 			dma_unmap_page(trans->dev,
430 				       iwl_pcie_tfd_tb_get_addr(trans, tfd, i),
431 				       iwl_pcie_tfd_tb_get_len(trans, tfd, i),
432 				       DMA_TO_DEVICE);
433 		else
434 			dma_unmap_single(trans->dev,
435 					 iwl_pcie_tfd_tb_get_addr(trans, tfd,
436 								  i),
437 					 iwl_pcie_tfd_tb_get_len(trans, tfd,
438 								 i),
439 					 DMA_TO_DEVICE);
440 	}
441 
442 	if (trans->cfg->use_tfh) {
443 		struct iwl_tfh_tfd *tfd_fh = (void *)tfd;
444 
445 		tfd_fh->num_tbs = 0;
446 	} else {
447 		struct iwl_tfd *tfd_fh = (void *)tfd;
448 
449 		tfd_fh->num_tbs = 0;
450 	}
451 
452 }
453 
454 /*
455  * iwl_pcie_txq_free_tfd - Free all chunks referenced by TFD [txq->q.read_ptr]
456  * @trans - transport private data
457  * @txq - tx queue
458  * @dma_dir - the direction of the DMA mapping
459  *
460  * Does NOT advance any TFD circular buffer read/write indexes
461  * Does NOT free the TFD itself (which is within circular buffer)
462  */
463 static void iwl_pcie_txq_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq)
464 {
465 	/* rd_ptr is bounded by TFD_QUEUE_SIZE_MAX and
466 	 * idx is bounded by n_window
467 	 */
468 	int rd_ptr = txq->read_ptr;
469 	int idx = get_cmd_index(txq, rd_ptr);
470 
471 	lockdep_assert_held(&txq->lock);
472 
473 	/* We have only q->n_window txq->entries, but we use
474 	 * TFD_QUEUE_SIZE_MAX tfds
475 	 */
476 	iwl_pcie_tfd_unmap(trans, &txq->entries[idx].meta, txq, rd_ptr);
477 
478 	/* free SKB */
479 	if (txq->entries) {
480 		struct sk_buff *skb;
481 
482 		skb = txq->entries[idx].skb;
483 
484 		/* Can be called from irqs-disabled context
485 		 * If skb is not NULL, it means that the whole queue is being
486 		 * freed and that the queue is not empty - free the skb
487 		 */
488 		if (skb) {
489 			iwl_op_mode_free_skb(trans->op_mode, skb);
490 			txq->entries[idx].skb = NULL;
491 		}
492 	}
493 }
494 
495 static int iwl_pcie_txq_build_tfd(struct iwl_trans *trans, struct iwl_txq *txq,
496 				  dma_addr_t addr, u16 len, bool reset)
497 {
498 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
499 	void *tfd;
500 	u32 num_tbs;
501 
502 	tfd = txq->tfds + trans_pcie->tfd_size * txq->write_ptr;
503 
504 	if (reset)
505 		memset(tfd, 0, trans_pcie->tfd_size);
506 
507 	num_tbs = iwl_pcie_tfd_get_num_tbs(trans, tfd);
508 
509 	/* Each TFD can point to a maximum max_tbs Tx buffers */
510 	if (num_tbs >= trans_pcie->max_tbs) {
511 		IWL_ERR(trans, "Error can not send more than %d chunks\n",
512 			trans_pcie->max_tbs);
513 		return -EINVAL;
514 	}
515 
516 	if (WARN(addr & ~IWL_TX_DMA_MASK,
517 		 "Unaligned address = %llx\n", (unsigned long long)addr))
518 		return -EINVAL;
519 
520 	iwl_pcie_tfd_set_tb(trans, tfd, num_tbs, addr, len);
521 
522 	return num_tbs;
523 }
524 
525 static int iwl_pcie_txq_alloc(struct iwl_trans *trans,
526 			       struct iwl_txq *txq, int slots_num,
527 			       u32 txq_id)
528 {
529 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
530 	size_t tfd_sz = trans_pcie->tfd_size * TFD_QUEUE_SIZE_MAX;
531 	size_t tb0_buf_sz;
532 	int i;
533 
534 	if (WARN_ON(txq->entries || txq->tfds))
535 		return -EINVAL;
536 
537 	setup_timer(&txq->stuck_timer, iwl_pcie_txq_stuck_timer,
538 		    (unsigned long)txq);
539 	txq->trans_pcie = trans_pcie;
540 
541 	txq->n_window = slots_num;
542 
543 	txq->entries = kcalloc(slots_num,
544 			       sizeof(struct iwl_pcie_txq_entry),
545 			       GFP_KERNEL);
546 
547 	if (!txq->entries)
548 		goto error;
549 
550 	if (txq_id == trans_pcie->cmd_queue)
551 		for (i = 0; i < slots_num; i++) {
552 			txq->entries[i].cmd =
553 				kmalloc(sizeof(struct iwl_device_cmd),
554 					GFP_KERNEL);
555 			if (!txq->entries[i].cmd)
556 				goto error;
557 		}
558 
559 	/* Circular buffer of transmit frame descriptors (TFDs),
560 	 * shared with device */
561 	txq->tfds = dma_alloc_coherent(trans->dev, tfd_sz,
562 				       &txq->dma_addr, GFP_KERNEL);
563 	if (!txq->tfds)
564 		goto error;
565 
566 	BUILD_BUG_ON(IWL_FIRST_TB_SIZE_ALIGN != sizeof(*txq->first_tb_bufs));
567 
568 	tb0_buf_sz = sizeof(*txq->first_tb_bufs) * slots_num;
569 
570 	txq->first_tb_bufs = dma_alloc_coherent(trans->dev, tb0_buf_sz,
571 					      &txq->first_tb_dma,
572 					      GFP_KERNEL);
573 	if (!txq->first_tb_bufs)
574 		goto err_free_tfds;
575 
576 	txq->id = txq_id;
577 
578 	return 0;
579 err_free_tfds:
580 	dma_free_coherent(trans->dev, tfd_sz, txq->tfds, txq->dma_addr);
581 error:
582 	if (txq->entries && txq_id == trans_pcie->cmd_queue)
583 		for (i = 0; i < slots_num; i++)
584 			kfree(txq->entries[i].cmd);
585 	kfree(txq->entries);
586 	txq->entries = NULL;
587 
588 	return -ENOMEM;
589 
590 }
591 
592 static int iwl_pcie_txq_init(struct iwl_trans *trans, struct iwl_txq *txq,
593 			      int slots_num, u32 txq_id)
594 {
595 	int ret;
596 
597 	txq->need_update = false;
598 
599 	/* TFD_QUEUE_SIZE_MAX must be power-of-two size, otherwise
600 	 * iwl_queue_inc_wrap and iwl_queue_dec_wrap are broken. */
601 	BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1));
602 
603 	/* Initialize queue's high/low-water marks, and head/tail indexes */
604 	ret = iwl_queue_init(txq, slots_num, txq_id);
605 	if (ret)
606 		return ret;
607 
608 	spin_lock_init(&txq->lock);
609 	__skb_queue_head_init(&txq->overflow_q);
610 
611 	/*
612 	 * Tell nic where to find circular buffer of Tx Frame Descriptors for
613 	 * given Tx queue, and enable the DMA channel used for that queue.
614 	 * Circular buffer (TFD queue in DRAM) physical base address */
615 	if (trans->cfg->use_tfh)
616 		iwl_write_direct64(trans,
617 				   FH_MEM_CBBC_QUEUE(trans, txq_id),
618 				   txq->dma_addr);
619 	else
620 		iwl_write_direct32(trans, FH_MEM_CBBC_QUEUE(trans, txq_id),
621 				   txq->dma_addr >> 8);
622 
623 	return 0;
624 }
625 
626 static void iwl_pcie_free_tso_page(struct iwl_trans_pcie *trans_pcie,
627 				   struct sk_buff *skb)
628 {
629 	struct page **page_ptr;
630 
631 	page_ptr = (void *)((u8 *)skb->cb + trans_pcie->page_offs);
632 
633 	if (*page_ptr) {
634 		__free_page(*page_ptr);
635 		*page_ptr = NULL;
636 	}
637 }
638 
639 static void iwl_pcie_clear_cmd_in_flight(struct iwl_trans *trans)
640 {
641 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
642 
643 	lockdep_assert_held(&trans_pcie->reg_lock);
644 
645 	if (trans_pcie->ref_cmd_in_flight) {
646 		trans_pcie->ref_cmd_in_flight = false;
647 		IWL_DEBUG_RPM(trans, "clear ref_cmd_in_flight - unref\n");
648 		iwl_trans_unref(trans);
649 	}
650 
651 	if (!trans->cfg->base_params->apmg_wake_up_wa)
652 		return;
653 	if (WARN_ON(!trans_pcie->cmd_hold_nic_awake))
654 		return;
655 
656 	trans_pcie->cmd_hold_nic_awake = false;
657 	__iwl_trans_pcie_clear_bit(trans, CSR_GP_CNTRL,
658 				   CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
659 }
660 
661 /*
662  * iwl_pcie_txq_unmap -  Unmap any remaining DMA mappings and free skb's
663  */
664 static void iwl_pcie_txq_unmap(struct iwl_trans *trans, int txq_id)
665 {
666 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
667 	struct iwl_txq *txq = &trans_pcie->txq[txq_id];
668 
669 	spin_lock_bh(&txq->lock);
670 	while (txq->write_ptr != txq->read_ptr) {
671 		IWL_DEBUG_TX_REPLY(trans, "Q %d Free %d\n",
672 				   txq_id, txq->read_ptr);
673 
674 		if (txq_id != trans_pcie->cmd_queue) {
675 			struct sk_buff *skb = txq->entries[txq->read_ptr].skb;
676 
677 			if (WARN_ON_ONCE(!skb))
678 				continue;
679 
680 			iwl_pcie_free_tso_page(trans_pcie, skb);
681 		}
682 		iwl_pcie_txq_free_tfd(trans, txq);
683 		txq->read_ptr = iwl_queue_inc_wrap(txq->read_ptr);
684 
685 		if (txq->read_ptr == txq->write_ptr) {
686 			unsigned long flags;
687 
688 			spin_lock_irqsave(&trans_pcie->reg_lock, flags);
689 			if (txq_id != trans_pcie->cmd_queue) {
690 				IWL_DEBUG_RPM(trans, "Q %d - last tx freed\n",
691 					      txq->id);
692 				iwl_trans_unref(trans);
693 			} else {
694 				iwl_pcie_clear_cmd_in_flight(trans);
695 			}
696 			spin_unlock_irqrestore(&trans_pcie->reg_lock, flags);
697 		}
698 	}
699 	txq->active = false;
700 
701 	while (!skb_queue_empty(&txq->overflow_q)) {
702 		struct sk_buff *skb = __skb_dequeue(&txq->overflow_q);
703 
704 		iwl_op_mode_free_skb(trans->op_mode, skb);
705 	}
706 
707 	spin_unlock_bh(&txq->lock);
708 
709 	/* just in case - this queue may have been stopped */
710 	iwl_wake_queue(trans, txq);
711 }
712 
713 /*
714  * iwl_pcie_txq_free - Deallocate DMA queue.
715  * @txq: Transmit queue to deallocate.
716  *
717  * Empty queue by removing and destroying all BD's.
718  * Free all buffers.
719  * 0-fill, but do not free "txq" descriptor structure.
720  */
721 static void iwl_pcie_txq_free(struct iwl_trans *trans, int txq_id)
722 {
723 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
724 	struct iwl_txq *txq = &trans_pcie->txq[txq_id];
725 	struct device *dev = trans->dev;
726 	int i;
727 
728 	if (WARN_ON(!txq))
729 		return;
730 
731 	iwl_pcie_txq_unmap(trans, txq_id);
732 
733 	/* De-alloc array of command/tx buffers */
734 	if (txq_id == trans_pcie->cmd_queue)
735 		for (i = 0; i < txq->n_window; i++) {
736 			kzfree(txq->entries[i].cmd);
737 			kzfree(txq->entries[i].free_buf);
738 		}
739 
740 	/* De-alloc circular buffer of TFDs */
741 	if (txq->tfds) {
742 		dma_free_coherent(dev,
743 				  trans_pcie->tfd_size * TFD_QUEUE_SIZE_MAX,
744 				  txq->tfds, txq->dma_addr);
745 		txq->dma_addr = 0;
746 		txq->tfds = NULL;
747 
748 		dma_free_coherent(dev,
749 				  sizeof(*txq->first_tb_bufs) * txq->n_window,
750 				  txq->first_tb_bufs, txq->first_tb_dma);
751 	}
752 
753 	kfree(txq->entries);
754 	txq->entries = NULL;
755 
756 	del_timer_sync(&txq->stuck_timer);
757 
758 	/* 0-fill queue descriptor structure */
759 	memset(txq, 0, sizeof(*txq));
760 }
761 
762 void iwl_pcie_tx_start(struct iwl_trans *trans, u32 scd_base_addr)
763 {
764 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
765 	int nq = trans->cfg->base_params->num_of_queues;
766 	int chan;
767 	u32 reg_val;
768 	int clear_dwords = (SCD_TRANS_TBL_OFFSET_QUEUE(nq) -
769 				SCD_CONTEXT_MEM_LOWER_BOUND) / sizeof(u32);
770 
771 	/* make sure all queue are not stopped/used */
772 	memset(trans_pcie->queue_stopped, 0, sizeof(trans_pcie->queue_stopped));
773 	memset(trans_pcie->queue_used, 0, sizeof(trans_pcie->queue_used));
774 
775 	if (trans->cfg->use_tfh)
776 		return;
777 
778 	trans_pcie->scd_base_addr =
779 		iwl_read_prph(trans, SCD_SRAM_BASE_ADDR);
780 
781 	WARN_ON(scd_base_addr != 0 &&
782 		scd_base_addr != trans_pcie->scd_base_addr);
783 
784 	/* reset context data, TX status and translation data */
785 	iwl_trans_write_mem(trans, trans_pcie->scd_base_addr +
786 				   SCD_CONTEXT_MEM_LOWER_BOUND,
787 			    NULL, clear_dwords);
788 
789 	iwl_write_prph(trans, SCD_DRAM_BASE_ADDR,
790 		       trans_pcie->scd_bc_tbls.dma >> 10);
791 
792 	/* The chain extension of the SCD doesn't work well. This feature is
793 	 * enabled by default by the HW, so we need to disable it manually.
794 	 */
795 	if (trans->cfg->base_params->scd_chain_ext_wa)
796 		iwl_write_prph(trans, SCD_CHAINEXT_EN, 0);
797 
798 	iwl_trans_ac_txq_enable(trans, trans_pcie->cmd_queue,
799 				trans_pcie->cmd_fifo,
800 				trans_pcie->cmd_q_wdg_timeout);
801 
802 	/* Activate all Tx DMA/FIFO channels */
803 	iwl_scd_activate_fifos(trans);
804 
805 	/* Enable DMA channel */
806 	for (chan = 0; chan < FH_TCSR_CHNL_NUM; chan++)
807 		iwl_write_direct32(trans, FH_TCSR_CHNL_TX_CONFIG_REG(chan),
808 				   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CHNL_ENABLE |
809 				   FH_TCSR_TX_CONFIG_REG_VAL_DMA_CREDIT_ENABLE);
810 
811 	/* Update FH chicken bits */
812 	reg_val = iwl_read_direct32(trans, FH_TX_CHICKEN_BITS_REG);
813 	iwl_write_direct32(trans, FH_TX_CHICKEN_BITS_REG,
814 			   reg_val | FH_TX_CHICKEN_BITS_SCD_AUTO_RETRY_EN);
815 
816 	/* Enable L1-Active */
817 	if (trans->cfg->device_family != IWL_DEVICE_FAMILY_8000)
818 		iwl_clear_bits_prph(trans, APMG_PCIDEV_STT_REG,
819 				    APMG_PCIDEV_STT_VAL_L1_ACT_DIS);
820 }
821 
822 void iwl_trans_pcie_tx_reset(struct iwl_trans *trans)
823 {
824 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
825 	int txq_id;
826 
827 	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
828 	     txq_id++) {
829 		struct iwl_txq *txq = &trans_pcie->txq[txq_id];
830 		if (trans->cfg->use_tfh)
831 			iwl_write_direct64(trans,
832 					   FH_MEM_CBBC_QUEUE(trans, txq_id),
833 					   txq->dma_addr);
834 		else
835 			iwl_write_direct32(trans,
836 					   FH_MEM_CBBC_QUEUE(trans, txq_id),
837 					   txq->dma_addr >> 8);
838 		iwl_pcie_txq_unmap(trans, txq_id);
839 		txq->read_ptr = 0;
840 		txq->write_ptr = 0;
841 	}
842 
843 	/* Tell NIC where to find the "keep warm" buffer */
844 	iwl_write_direct32(trans, FH_KW_MEM_ADDR_REG,
845 			   trans_pcie->kw.dma >> 4);
846 
847 	/*
848 	 * Send 0 as the scd_base_addr since the device may have be reset
849 	 * while we were in WoWLAN in which case SCD_SRAM_BASE_ADDR will
850 	 * contain garbage.
851 	 */
852 	iwl_pcie_tx_start(trans, 0);
853 }
854 
855 static void iwl_pcie_tx_stop_fh(struct iwl_trans *trans)
856 {
857 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
858 	unsigned long flags;
859 	int ch, ret;
860 	u32 mask = 0;
861 
862 	spin_lock(&trans_pcie->irq_lock);
863 
864 	if (!iwl_trans_grab_nic_access(trans, &flags))
865 		goto out;
866 
867 	/* Stop each Tx DMA channel */
868 	for (ch = 0; ch < FH_TCSR_CHNL_NUM; ch++) {
869 		iwl_write32(trans, FH_TCSR_CHNL_TX_CONFIG_REG(ch), 0x0);
870 		mask |= FH_TSSR_TX_STATUS_REG_MSK_CHNL_IDLE(ch);
871 	}
872 
873 	/* Wait for DMA channels to be idle */
874 	ret = iwl_poll_bit(trans, FH_TSSR_TX_STATUS_REG, mask, mask, 5000);
875 	if (ret < 0)
876 		IWL_ERR(trans,
877 			"Failing on timeout while stopping DMA channel %d [0x%08x]\n",
878 			ch, iwl_read32(trans, FH_TSSR_TX_STATUS_REG));
879 
880 	iwl_trans_release_nic_access(trans, &flags);
881 
882 out:
883 	spin_unlock(&trans_pcie->irq_lock);
884 }
885 
886 /*
887  * iwl_pcie_tx_stop - Stop all Tx DMA channels
888  */
889 int iwl_pcie_tx_stop(struct iwl_trans *trans)
890 {
891 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
892 	int txq_id;
893 
894 	/* Turn off all Tx DMA fifos */
895 	iwl_scd_deactivate_fifos(trans);
896 
897 	/* Turn off all Tx DMA channels */
898 	iwl_pcie_tx_stop_fh(trans);
899 
900 	/*
901 	 * This function can be called before the op_mode disabled the
902 	 * queues. This happens when we have an rfkill interrupt.
903 	 * Since we stop Tx altogether - mark the queues as stopped.
904 	 */
905 	memset(trans_pcie->queue_stopped, 0, sizeof(trans_pcie->queue_stopped));
906 	memset(trans_pcie->queue_used, 0, sizeof(trans_pcie->queue_used));
907 
908 	/* This can happen: start_hw, stop_device */
909 	if (!trans_pcie->txq)
910 		return 0;
911 
912 	/* Unmap DMA from host system and free skb's */
913 	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
914 	     txq_id++)
915 		iwl_pcie_txq_unmap(trans, txq_id);
916 
917 	return 0;
918 }
919 
920 /*
921  * iwl_trans_tx_free - Free TXQ Context
922  *
923  * Destroy all TX DMA queues and structures
924  */
925 void iwl_pcie_tx_free(struct iwl_trans *trans)
926 {
927 	int txq_id;
928 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
929 
930 	/* Tx queues */
931 	if (trans_pcie->txq) {
932 		for (txq_id = 0;
933 		     txq_id < trans->cfg->base_params->num_of_queues; txq_id++)
934 			iwl_pcie_txq_free(trans, txq_id);
935 	}
936 
937 	kfree(trans_pcie->txq);
938 	trans_pcie->txq = NULL;
939 
940 	iwl_pcie_free_dma_ptr(trans, &trans_pcie->kw);
941 
942 	iwl_pcie_free_dma_ptr(trans, &trans_pcie->scd_bc_tbls);
943 }
944 
945 /*
946  * iwl_pcie_tx_alloc - allocate TX context
947  * Allocate all Tx DMA structures and initialize them
948  */
949 static int iwl_pcie_tx_alloc(struct iwl_trans *trans)
950 {
951 	int ret;
952 	int txq_id, slots_num;
953 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
954 
955 	u16 scd_bc_tbls_size = trans->cfg->base_params->num_of_queues *
956 			sizeof(struct iwlagn_scd_bc_tbl);
957 
958 	/*It is not allowed to alloc twice, so warn when this happens.
959 	 * We cannot rely on the previous allocation, so free and fail */
960 	if (WARN_ON(trans_pcie->txq)) {
961 		ret = -EINVAL;
962 		goto error;
963 	}
964 
965 	ret = iwl_pcie_alloc_dma_ptr(trans, &trans_pcie->scd_bc_tbls,
966 				   scd_bc_tbls_size);
967 	if (ret) {
968 		IWL_ERR(trans, "Scheduler BC Table allocation failed\n");
969 		goto error;
970 	}
971 
972 	/* Alloc keep-warm buffer */
973 	ret = iwl_pcie_alloc_dma_ptr(trans, &trans_pcie->kw, IWL_KW_SIZE);
974 	if (ret) {
975 		IWL_ERR(trans, "Keep Warm allocation failed\n");
976 		goto error;
977 	}
978 
979 	trans_pcie->txq = kcalloc(trans->cfg->base_params->num_of_queues,
980 				  sizeof(struct iwl_txq), GFP_KERNEL);
981 	if (!trans_pcie->txq) {
982 		IWL_ERR(trans, "Not enough memory for txq\n");
983 		ret = -ENOMEM;
984 		goto error;
985 	}
986 
987 	/* Alloc and init all Tx queues, including the command queue (#4/#9) */
988 	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
989 	     txq_id++) {
990 		slots_num = (txq_id == trans_pcie->cmd_queue) ?
991 					TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
992 		ret = iwl_pcie_txq_alloc(trans, &trans_pcie->txq[txq_id],
993 					  slots_num, txq_id);
994 		if (ret) {
995 			IWL_ERR(trans, "Tx %d queue alloc failed\n", txq_id);
996 			goto error;
997 		}
998 	}
999 
1000 	return 0;
1001 
1002 error:
1003 	iwl_pcie_tx_free(trans);
1004 
1005 	return ret;
1006 }
1007 int iwl_pcie_tx_init(struct iwl_trans *trans)
1008 {
1009 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1010 	int ret;
1011 	int txq_id, slots_num;
1012 	bool alloc = false;
1013 
1014 	if (!trans_pcie->txq) {
1015 		ret = iwl_pcie_tx_alloc(trans);
1016 		if (ret)
1017 			goto error;
1018 		alloc = true;
1019 	}
1020 
1021 	spin_lock(&trans_pcie->irq_lock);
1022 
1023 	/* Turn off all Tx DMA fifos */
1024 	iwl_scd_deactivate_fifos(trans);
1025 
1026 	/* Tell NIC where to find the "keep warm" buffer */
1027 	iwl_write_direct32(trans, FH_KW_MEM_ADDR_REG,
1028 			   trans_pcie->kw.dma >> 4);
1029 
1030 	spin_unlock(&trans_pcie->irq_lock);
1031 
1032 	/* Alloc and init all Tx queues, including the command queue (#4/#9) */
1033 	for (txq_id = 0; txq_id < trans->cfg->base_params->num_of_queues;
1034 	     txq_id++) {
1035 		slots_num = (txq_id == trans_pcie->cmd_queue) ?
1036 					TFD_CMD_SLOTS : TFD_TX_CMD_SLOTS;
1037 		ret = iwl_pcie_txq_init(trans, &trans_pcie->txq[txq_id],
1038 					 slots_num, txq_id);
1039 		if (ret) {
1040 			IWL_ERR(trans, "Tx %d queue init failed\n", txq_id);
1041 			goto error;
1042 		}
1043 	}
1044 
1045 	if (trans->cfg->use_tfh) {
1046 		iwl_write_direct32(trans, TFH_TRANSFER_MODE,
1047 				   TFH_TRANSFER_MAX_PENDING_REQ |
1048 				   TFH_CHUNK_SIZE_128 |
1049 				   TFH_CHUNK_SPLIT_MODE);
1050 		return 0;
1051 	}
1052 
1053 	iwl_set_bits_prph(trans, SCD_GP_CTRL, SCD_GP_CTRL_AUTO_ACTIVE_MODE);
1054 	if (trans->cfg->base_params->num_of_queues > 20)
1055 		iwl_set_bits_prph(trans, SCD_GP_CTRL,
1056 				  SCD_GP_CTRL_ENABLE_31_QUEUES);
1057 
1058 	return 0;
1059 error:
1060 	/*Upon error, free only if we allocated something */
1061 	if (alloc)
1062 		iwl_pcie_tx_free(trans);
1063 	return ret;
1064 }
1065 
1066 static inline void iwl_pcie_txq_progress(struct iwl_txq *txq)
1067 {
1068 	lockdep_assert_held(&txq->lock);
1069 
1070 	if (!txq->wd_timeout)
1071 		return;
1072 
1073 	/*
1074 	 * station is asleep and we send data - that must
1075 	 * be uAPSD or PS-Poll. Don't rearm the timer.
1076 	 */
1077 	if (txq->frozen)
1078 		return;
1079 
1080 	/*
1081 	 * if empty delete timer, otherwise move timer forward
1082 	 * since we're making progress on this queue
1083 	 */
1084 	if (txq->read_ptr == txq->write_ptr)
1085 		del_timer(&txq->stuck_timer);
1086 	else
1087 		mod_timer(&txq->stuck_timer, jiffies + txq->wd_timeout);
1088 }
1089 
1090 /* Frees buffers until index _not_ inclusive */
1091 void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn,
1092 			    struct sk_buff_head *skbs)
1093 {
1094 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1095 	struct iwl_txq *txq = &trans_pcie->txq[txq_id];
1096 	int tfd_num = ssn & (TFD_QUEUE_SIZE_MAX - 1);
1097 	int last_to_free;
1098 
1099 	/* This function is not meant to release cmd queue*/
1100 	if (WARN_ON(txq_id == trans_pcie->cmd_queue))
1101 		return;
1102 
1103 	spin_lock_bh(&txq->lock);
1104 
1105 	if (!txq->active) {
1106 		IWL_DEBUG_TX_QUEUES(trans, "Q %d inactive - ignoring idx %d\n",
1107 				    txq_id, ssn);
1108 		goto out;
1109 	}
1110 
1111 	if (txq->read_ptr == tfd_num)
1112 		goto out;
1113 
1114 	IWL_DEBUG_TX_REPLY(trans, "[Q %d] %d -> %d (%d)\n",
1115 			   txq_id, txq->read_ptr, tfd_num, ssn);
1116 
1117 	/*Since we free until index _not_ inclusive, the one before index is
1118 	 * the last we will free. This one must be used */
1119 	last_to_free = iwl_queue_dec_wrap(tfd_num);
1120 
1121 	if (!iwl_queue_used(txq, last_to_free)) {
1122 		IWL_ERR(trans,
1123 			"%s: Read index for DMA queue txq id (%d), last_to_free %d is out of range [0-%d] %d %d.\n",
1124 			__func__, txq_id, last_to_free, TFD_QUEUE_SIZE_MAX,
1125 			txq->write_ptr, txq->read_ptr);
1126 		goto out;
1127 	}
1128 
1129 	if (WARN_ON(!skb_queue_empty(skbs)))
1130 		goto out;
1131 
1132 	for (;
1133 	     txq->read_ptr != tfd_num;
1134 	     txq->read_ptr = iwl_queue_inc_wrap(txq->read_ptr)) {
1135 		struct sk_buff *skb = txq->entries[txq->read_ptr].skb;
1136 
1137 		if (WARN_ON_ONCE(!skb))
1138 			continue;
1139 
1140 		iwl_pcie_free_tso_page(trans_pcie, skb);
1141 
1142 		__skb_queue_tail(skbs, skb);
1143 
1144 		txq->entries[txq->read_ptr].skb = NULL;
1145 
1146 		if (!trans->cfg->use_tfh)
1147 			iwl_pcie_txq_inval_byte_cnt_tbl(trans, txq);
1148 
1149 		iwl_pcie_txq_free_tfd(trans, txq);
1150 	}
1151 
1152 	iwl_pcie_txq_progress(txq);
1153 
1154 	if (iwl_queue_space(txq) > txq->low_mark &&
1155 	    test_bit(txq_id, trans_pcie->queue_stopped)) {
1156 		struct sk_buff_head overflow_skbs;
1157 
1158 		__skb_queue_head_init(&overflow_skbs);
1159 		skb_queue_splice_init(&txq->overflow_q, &overflow_skbs);
1160 
1161 		/*
1162 		 * This is tricky: we are in reclaim path which is non
1163 		 * re-entrant, so noone will try to take the access the
1164 		 * txq data from that path. We stopped tx, so we can't
1165 		 * have tx as well. Bottom line, we can unlock and re-lock
1166 		 * later.
1167 		 */
1168 		spin_unlock_bh(&txq->lock);
1169 
1170 		while (!skb_queue_empty(&overflow_skbs)) {
1171 			struct sk_buff *skb = __skb_dequeue(&overflow_skbs);
1172 			struct iwl_device_cmd *dev_cmd_ptr;
1173 
1174 			dev_cmd_ptr = *(void **)((u8 *)skb->cb +
1175 						 trans_pcie->dev_cmd_offs);
1176 
1177 			/*
1178 			 * Note that we can very well be overflowing again.
1179 			 * In that case, iwl_queue_space will be small again
1180 			 * and we won't wake mac80211's queue.
1181 			 */
1182 			iwl_trans_pcie_tx(trans, skb, dev_cmd_ptr, txq_id);
1183 		}
1184 		spin_lock_bh(&txq->lock);
1185 
1186 		if (iwl_queue_space(txq) > txq->low_mark)
1187 			iwl_wake_queue(trans, txq);
1188 	}
1189 
1190 	if (txq->read_ptr == txq->write_ptr) {
1191 		IWL_DEBUG_RPM(trans, "Q %d - last tx reclaimed\n", txq->id);
1192 		iwl_trans_unref(trans);
1193 	}
1194 
1195 out:
1196 	spin_unlock_bh(&txq->lock);
1197 }
1198 
1199 static int iwl_pcie_set_cmd_in_flight(struct iwl_trans *trans,
1200 				      const struct iwl_host_cmd *cmd)
1201 {
1202 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1203 	int ret;
1204 
1205 	lockdep_assert_held(&trans_pcie->reg_lock);
1206 
1207 	if (!(cmd->flags & CMD_SEND_IN_IDLE) &&
1208 	    !trans_pcie->ref_cmd_in_flight) {
1209 		trans_pcie->ref_cmd_in_flight = true;
1210 		IWL_DEBUG_RPM(trans, "set ref_cmd_in_flight - ref\n");
1211 		iwl_trans_ref(trans);
1212 	}
1213 
1214 	/*
1215 	 * wake up the NIC to make sure that the firmware will see the host
1216 	 * command - we will let the NIC sleep once all the host commands
1217 	 * returned. This needs to be done only on NICs that have
1218 	 * apmg_wake_up_wa set.
1219 	 */
1220 	if (trans->cfg->base_params->apmg_wake_up_wa &&
1221 	    !trans_pcie->cmd_hold_nic_awake) {
1222 		__iwl_trans_pcie_set_bit(trans, CSR_GP_CNTRL,
1223 					 CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
1224 
1225 		ret = iwl_poll_bit(trans, CSR_GP_CNTRL,
1226 				   CSR_GP_CNTRL_REG_VAL_MAC_ACCESS_EN,
1227 				   (CSR_GP_CNTRL_REG_FLAG_MAC_CLOCK_READY |
1228 				    CSR_GP_CNTRL_REG_FLAG_GOING_TO_SLEEP),
1229 				   15000);
1230 		if (ret < 0) {
1231 			__iwl_trans_pcie_clear_bit(trans, CSR_GP_CNTRL,
1232 					CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
1233 			IWL_ERR(trans, "Failed to wake NIC for hcmd\n");
1234 			return -EIO;
1235 		}
1236 		trans_pcie->cmd_hold_nic_awake = true;
1237 	}
1238 
1239 	return 0;
1240 }
1241 
1242 /*
1243  * iwl_pcie_cmdq_reclaim - Reclaim TX command queue entries already Tx'd
1244  *
1245  * When FW advances 'R' index, all entries between old and new 'R' index
1246  * need to be reclaimed. As result, some free space forms.  If there is
1247  * enough free space (> low mark), wake the stack that feeds us.
1248  */
1249 static void iwl_pcie_cmdq_reclaim(struct iwl_trans *trans, int txq_id, int idx)
1250 {
1251 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1252 	struct iwl_txq *txq = &trans_pcie->txq[txq_id];
1253 	unsigned long flags;
1254 	int nfreed = 0;
1255 
1256 	lockdep_assert_held(&txq->lock);
1257 
1258 	if ((idx >= TFD_QUEUE_SIZE_MAX) || (!iwl_queue_used(txq, idx))) {
1259 		IWL_ERR(trans,
1260 			"%s: Read index for DMA queue txq id (%d), index %d is out of range [0-%d] %d %d.\n",
1261 			__func__, txq_id, idx, TFD_QUEUE_SIZE_MAX,
1262 			txq->write_ptr, txq->read_ptr);
1263 		return;
1264 	}
1265 
1266 	for (idx = iwl_queue_inc_wrap(idx); txq->read_ptr != idx;
1267 	     txq->read_ptr = iwl_queue_inc_wrap(txq->read_ptr)) {
1268 
1269 		if (nfreed++ > 0) {
1270 			IWL_ERR(trans, "HCMD skipped: index (%d) %d %d\n",
1271 				idx, txq->write_ptr, txq->read_ptr);
1272 			iwl_force_nmi(trans);
1273 		}
1274 	}
1275 
1276 	if (txq->read_ptr == txq->write_ptr) {
1277 		spin_lock_irqsave(&trans_pcie->reg_lock, flags);
1278 		iwl_pcie_clear_cmd_in_flight(trans);
1279 		spin_unlock_irqrestore(&trans_pcie->reg_lock, flags);
1280 	}
1281 
1282 	iwl_pcie_txq_progress(txq);
1283 }
1284 
1285 static int iwl_pcie_txq_set_ratid_map(struct iwl_trans *trans, u16 ra_tid,
1286 				 u16 txq_id)
1287 {
1288 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1289 	u32 tbl_dw_addr;
1290 	u32 tbl_dw;
1291 	u16 scd_q2ratid;
1292 
1293 	scd_q2ratid = ra_tid & SCD_QUEUE_RA_TID_MAP_RATID_MSK;
1294 
1295 	tbl_dw_addr = trans_pcie->scd_base_addr +
1296 			SCD_TRANS_TBL_OFFSET_QUEUE(txq_id);
1297 
1298 	tbl_dw = iwl_trans_read_mem32(trans, tbl_dw_addr);
1299 
1300 	if (txq_id & 0x1)
1301 		tbl_dw = (scd_q2ratid << 16) | (tbl_dw & 0x0000FFFF);
1302 	else
1303 		tbl_dw = scd_q2ratid | (tbl_dw & 0xFFFF0000);
1304 
1305 	iwl_trans_write_mem32(trans, tbl_dw_addr, tbl_dw);
1306 
1307 	return 0;
1308 }
1309 
1310 /* Receiver address (actually, Rx station's index into station table),
1311  * combined with Traffic ID (QOS priority), in format used by Tx Scheduler */
1312 #define BUILD_RAxTID(sta_id, tid)	(((sta_id) << 4) + (tid))
1313 
1314 void iwl_trans_pcie_txq_enable(struct iwl_trans *trans, int txq_id, u16 ssn,
1315 			       const struct iwl_trans_txq_scd_cfg *cfg,
1316 			       unsigned int wdg_timeout)
1317 {
1318 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1319 	struct iwl_txq *txq = &trans_pcie->txq[txq_id];
1320 	int fifo = -1;
1321 
1322 	if (test_and_set_bit(txq_id, trans_pcie->queue_used))
1323 		WARN_ONCE(1, "queue %d already used - expect issues", txq_id);
1324 
1325 	if (cfg && trans->cfg->use_tfh)
1326 		WARN_ONCE(1, "Expected no calls to SCD configuration");
1327 
1328 	txq->wd_timeout = msecs_to_jiffies(wdg_timeout);
1329 
1330 	if (cfg) {
1331 		fifo = cfg->fifo;
1332 
1333 		/* Disable the scheduler prior configuring the cmd queue */
1334 		if (txq_id == trans_pcie->cmd_queue &&
1335 		    trans_pcie->scd_set_active)
1336 			iwl_scd_enable_set_active(trans, 0);
1337 
1338 		/* Stop this Tx queue before configuring it */
1339 		iwl_scd_txq_set_inactive(trans, txq_id);
1340 
1341 		/* Set this queue as a chain-building queue unless it is CMD */
1342 		if (txq_id != trans_pcie->cmd_queue)
1343 			iwl_scd_txq_set_chain(trans, txq_id);
1344 
1345 		if (cfg->aggregate) {
1346 			u16 ra_tid = BUILD_RAxTID(cfg->sta_id, cfg->tid);
1347 
1348 			/* Map receiver-address / traffic-ID to this queue */
1349 			iwl_pcie_txq_set_ratid_map(trans, ra_tid, txq_id);
1350 
1351 			/* enable aggregations for the queue */
1352 			iwl_scd_txq_enable_agg(trans, txq_id);
1353 			txq->ampdu = true;
1354 		} else {
1355 			/*
1356 			 * disable aggregations for the queue, this will also
1357 			 * make the ra_tid mapping configuration irrelevant
1358 			 * since it is now a non-AGG queue.
1359 			 */
1360 			iwl_scd_txq_disable_agg(trans, txq_id);
1361 
1362 			ssn = txq->read_ptr;
1363 		}
1364 	}
1365 
1366 	/* Place first TFD at index corresponding to start sequence number.
1367 	 * Assumes that ssn_idx is valid (!= 0xFFF) */
1368 	txq->read_ptr = (ssn & 0xff);
1369 	txq->write_ptr = (ssn & 0xff);
1370 	iwl_write_direct32(trans, HBUS_TARG_WRPTR,
1371 			   (ssn & 0xff) | (txq_id << 8));
1372 
1373 	if (cfg) {
1374 		u8 frame_limit = cfg->frame_limit;
1375 
1376 		iwl_write_prph(trans, SCD_QUEUE_RDPTR(txq_id), ssn);
1377 
1378 		/* Set up Tx window size and frame limit for this queue */
1379 		iwl_trans_write_mem32(trans, trans_pcie->scd_base_addr +
1380 				SCD_CONTEXT_QUEUE_OFFSET(txq_id), 0);
1381 		iwl_trans_write_mem32(trans,
1382 			trans_pcie->scd_base_addr +
1383 			SCD_CONTEXT_QUEUE_OFFSET(txq_id) + sizeof(u32),
1384 			((frame_limit << SCD_QUEUE_CTX_REG2_WIN_SIZE_POS) &
1385 					SCD_QUEUE_CTX_REG2_WIN_SIZE_MSK) |
1386 			((frame_limit << SCD_QUEUE_CTX_REG2_FRAME_LIMIT_POS) &
1387 					SCD_QUEUE_CTX_REG2_FRAME_LIMIT_MSK));
1388 
1389 		/* Set up status area in SRAM, map to Tx DMA/FIFO, activate */
1390 		iwl_write_prph(trans, SCD_QUEUE_STATUS_BITS(txq_id),
1391 			       (1 << SCD_QUEUE_STTS_REG_POS_ACTIVE) |
1392 			       (cfg->fifo << SCD_QUEUE_STTS_REG_POS_TXF) |
1393 			       (1 << SCD_QUEUE_STTS_REG_POS_WSL) |
1394 			       SCD_QUEUE_STTS_REG_MSK);
1395 
1396 		/* enable the scheduler for this queue (only) */
1397 		if (txq_id == trans_pcie->cmd_queue &&
1398 		    trans_pcie->scd_set_active)
1399 			iwl_scd_enable_set_active(trans, BIT(txq_id));
1400 
1401 		IWL_DEBUG_TX_QUEUES(trans,
1402 				    "Activate queue %d on FIFO %d WrPtr: %d\n",
1403 				    txq_id, fifo, ssn & 0xff);
1404 	} else {
1405 		IWL_DEBUG_TX_QUEUES(trans,
1406 				    "Activate queue %d WrPtr: %d\n",
1407 				    txq_id, ssn & 0xff);
1408 	}
1409 
1410 	txq->active = true;
1411 }
1412 
1413 void iwl_trans_pcie_txq_set_shared_mode(struct iwl_trans *trans, u32 txq_id,
1414 					bool shared_mode)
1415 {
1416 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1417 	struct iwl_txq *txq = &trans_pcie->txq[txq_id];
1418 
1419 	txq->ampdu = !shared_mode;
1420 }
1421 
1422 dma_addr_t iwl_trans_pcie_get_txq_byte_table(struct iwl_trans *trans, int txq)
1423 {
1424 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1425 
1426 	return trans_pcie->scd_bc_tbls.dma +
1427 	       txq * sizeof(struct iwlagn_scd_bc_tbl);
1428 }
1429 
1430 void iwl_trans_pcie_txq_disable(struct iwl_trans *trans, int txq_id,
1431 				bool configure_scd)
1432 {
1433 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1434 	u32 stts_addr = trans_pcie->scd_base_addr +
1435 			SCD_TX_STTS_QUEUE_OFFSET(txq_id);
1436 	static const u32 zero_val[4] = {};
1437 
1438 	trans_pcie->txq[txq_id].frozen_expiry_remainder = 0;
1439 	trans_pcie->txq[txq_id].frozen = false;
1440 
1441 	/*
1442 	 * Upon HW Rfkill - we stop the device, and then stop the queues
1443 	 * in the op_mode. Just for the sake of the simplicity of the op_mode,
1444 	 * allow the op_mode to call txq_disable after it already called
1445 	 * stop_device.
1446 	 */
1447 	if (!test_and_clear_bit(txq_id, trans_pcie->queue_used)) {
1448 		WARN_ONCE(test_bit(STATUS_DEVICE_ENABLED, &trans->status),
1449 			  "queue %d not used", txq_id);
1450 		return;
1451 	}
1452 
1453 	if (configure_scd && trans->cfg->use_tfh)
1454 		WARN_ONCE(1, "Expected no calls to SCD configuration");
1455 
1456 	if (configure_scd) {
1457 		iwl_scd_txq_set_inactive(trans, txq_id);
1458 
1459 		iwl_trans_write_mem(trans, stts_addr, (void *)zero_val,
1460 				    ARRAY_SIZE(zero_val));
1461 	}
1462 
1463 	iwl_pcie_txq_unmap(trans, txq_id);
1464 	trans_pcie->txq[txq_id].ampdu = false;
1465 
1466 	IWL_DEBUG_TX_QUEUES(trans, "Deactivate queue %d\n", txq_id);
1467 }
1468 
1469 /*************** HOST COMMAND QUEUE FUNCTIONS   *****/
1470 
1471 /*
1472  * iwl_pcie_enqueue_hcmd - enqueue a uCode command
1473  * @priv: device private data point
1474  * @cmd: a pointer to the ucode command structure
1475  *
1476  * The function returns < 0 values to indicate the operation
1477  * failed. On success, it returns the index (>= 0) of command in the
1478  * command queue.
1479  */
1480 static int iwl_pcie_enqueue_hcmd(struct iwl_trans *trans,
1481 				 struct iwl_host_cmd *cmd)
1482 {
1483 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1484 	struct iwl_txq *txq = &trans_pcie->txq[trans_pcie->cmd_queue];
1485 	struct iwl_device_cmd *out_cmd;
1486 	struct iwl_cmd_meta *out_meta;
1487 	unsigned long flags;
1488 	void *dup_buf = NULL;
1489 	dma_addr_t phys_addr;
1490 	int idx;
1491 	u16 copy_size, cmd_size, tb0_size;
1492 	bool had_nocopy = false;
1493 	u8 group_id = iwl_cmd_groupid(cmd->id);
1494 	int i, ret;
1495 	u32 cmd_pos;
1496 	const u8 *cmddata[IWL_MAX_CMD_TBS_PER_TFD];
1497 	u16 cmdlen[IWL_MAX_CMD_TBS_PER_TFD];
1498 
1499 	if (WARN(!trans->wide_cmd_header &&
1500 		 group_id > IWL_ALWAYS_LONG_GROUP,
1501 		 "unsupported wide command %#x\n", cmd->id))
1502 		return -EINVAL;
1503 
1504 	if (group_id != 0) {
1505 		copy_size = sizeof(struct iwl_cmd_header_wide);
1506 		cmd_size = sizeof(struct iwl_cmd_header_wide);
1507 	} else {
1508 		copy_size = sizeof(struct iwl_cmd_header);
1509 		cmd_size = sizeof(struct iwl_cmd_header);
1510 	}
1511 
1512 	/* need one for the header if the first is NOCOPY */
1513 	BUILD_BUG_ON(IWL_MAX_CMD_TBS_PER_TFD > IWL_NUM_OF_TBS - 1);
1514 
1515 	for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
1516 		cmddata[i] = cmd->data[i];
1517 		cmdlen[i] = cmd->len[i];
1518 
1519 		if (!cmd->len[i])
1520 			continue;
1521 
1522 		/* need at least IWL_FIRST_TB_SIZE copied */
1523 		if (copy_size < IWL_FIRST_TB_SIZE) {
1524 			int copy = IWL_FIRST_TB_SIZE - copy_size;
1525 
1526 			if (copy > cmdlen[i])
1527 				copy = cmdlen[i];
1528 			cmdlen[i] -= copy;
1529 			cmddata[i] += copy;
1530 			copy_size += copy;
1531 		}
1532 
1533 		if (cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY) {
1534 			had_nocopy = true;
1535 			if (WARN_ON(cmd->dataflags[i] & IWL_HCMD_DFL_DUP)) {
1536 				idx = -EINVAL;
1537 				goto free_dup_buf;
1538 			}
1539 		} else if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP) {
1540 			/*
1541 			 * This is also a chunk that isn't copied
1542 			 * to the static buffer so set had_nocopy.
1543 			 */
1544 			had_nocopy = true;
1545 
1546 			/* only allowed once */
1547 			if (WARN_ON(dup_buf)) {
1548 				idx = -EINVAL;
1549 				goto free_dup_buf;
1550 			}
1551 
1552 			dup_buf = kmemdup(cmddata[i], cmdlen[i],
1553 					  GFP_ATOMIC);
1554 			if (!dup_buf)
1555 				return -ENOMEM;
1556 		} else {
1557 			/* NOCOPY must not be followed by normal! */
1558 			if (WARN_ON(had_nocopy)) {
1559 				idx = -EINVAL;
1560 				goto free_dup_buf;
1561 			}
1562 			copy_size += cmdlen[i];
1563 		}
1564 		cmd_size += cmd->len[i];
1565 	}
1566 
1567 	/*
1568 	 * If any of the command structures end up being larger than
1569 	 * the TFD_MAX_PAYLOAD_SIZE and they aren't dynamically
1570 	 * allocated into separate TFDs, then we will need to
1571 	 * increase the size of the buffers.
1572 	 */
1573 	if (WARN(copy_size > TFD_MAX_PAYLOAD_SIZE,
1574 		 "Command %s (%#x) is too large (%d bytes)\n",
1575 		 iwl_get_cmd_string(trans, cmd->id),
1576 		 cmd->id, copy_size)) {
1577 		idx = -EINVAL;
1578 		goto free_dup_buf;
1579 	}
1580 
1581 	spin_lock_bh(&txq->lock);
1582 
1583 	if (iwl_queue_space(txq) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
1584 		spin_unlock_bh(&txq->lock);
1585 
1586 		IWL_ERR(trans, "No space in command queue\n");
1587 		iwl_op_mode_cmd_queue_full(trans->op_mode);
1588 		idx = -ENOSPC;
1589 		goto free_dup_buf;
1590 	}
1591 
1592 	idx = get_cmd_index(txq, txq->write_ptr);
1593 	out_cmd = txq->entries[idx].cmd;
1594 	out_meta = &txq->entries[idx].meta;
1595 
1596 	memset(out_meta, 0, sizeof(*out_meta));	/* re-initialize to NULL */
1597 	if (cmd->flags & CMD_WANT_SKB)
1598 		out_meta->source = cmd;
1599 
1600 	/* set up the header */
1601 	if (group_id != 0) {
1602 		out_cmd->hdr_wide.cmd = iwl_cmd_opcode(cmd->id);
1603 		out_cmd->hdr_wide.group_id = group_id;
1604 		out_cmd->hdr_wide.version = iwl_cmd_version(cmd->id);
1605 		out_cmd->hdr_wide.length =
1606 			cpu_to_le16(cmd_size -
1607 				    sizeof(struct iwl_cmd_header_wide));
1608 		out_cmd->hdr_wide.reserved = 0;
1609 		out_cmd->hdr_wide.sequence =
1610 			cpu_to_le16(QUEUE_TO_SEQ(trans_pcie->cmd_queue) |
1611 						 INDEX_TO_SEQ(txq->write_ptr));
1612 
1613 		cmd_pos = sizeof(struct iwl_cmd_header_wide);
1614 		copy_size = sizeof(struct iwl_cmd_header_wide);
1615 	} else {
1616 		out_cmd->hdr.cmd = iwl_cmd_opcode(cmd->id);
1617 		out_cmd->hdr.sequence =
1618 			cpu_to_le16(QUEUE_TO_SEQ(trans_pcie->cmd_queue) |
1619 						 INDEX_TO_SEQ(txq->write_ptr));
1620 		out_cmd->hdr.group_id = 0;
1621 
1622 		cmd_pos = sizeof(struct iwl_cmd_header);
1623 		copy_size = sizeof(struct iwl_cmd_header);
1624 	}
1625 
1626 	/* and copy the data that needs to be copied */
1627 	for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
1628 		int copy;
1629 
1630 		if (!cmd->len[i])
1631 			continue;
1632 
1633 		/* copy everything if not nocopy/dup */
1634 		if (!(cmd->dataflags[i] & (IWL_HCMD_DFL_NOCOPY |
1635 					   IWL_HCMD_DFL_DUP))) {
1636 			copy = cmd->len[i];
1637 
1638 			memcpy((u8 *)out_cmd + cmd_pos, cmd->data[i], copy);
1639 			cmd_pos += copy;
1640 			copy_size += copy;
1641 			continue;
1642 		}
1643 
1644 		/*
1645 		 * Otherwise we need at least IWL_FIRST_TB_SIZE copied
1646 		 * in total (for bi-directional DMA), but copy up to what
1647 		 * we can fit into the payload for debug dump purposes.
1648 		 */
1649 		copy = min_t(int, TFD_MAX_PAYLOAD_SIZE - cmd_pos, cmd->len[i]);
1650 
1651 		memcpy((u8 *)out_cmd + cmd_pos, cmd->data[i], copy);
1652 		cmd_pos += copy;
1653 
1654 		/* However, treat copy_size the proper way, we need it below */
1655 		if (copy_size < IWL_FIRST_TB_SIZE) {
1656 			copy = IWL_FIRST_TB_SIZE - copy_size;
1657 
1658 			if (copy > cmd->len[i])
1659 				copy = cmd->len[i];
1660 			copy_size += copy;
1661 		}
1662 	}
1663 
1664 	IWL_DEBUG_HC(trans,
1665 		     "Sending command %s (%.2x.%.2x), seq: 0x%04X, %d bytes at %d[%d]:%d\n",
1666 		     iwl_get_cmd_string(trans, cmd->id),
1667 		     group_id, out_cmd->hdr.cmd,
1668 		     le16_to_cpu(out_cmd->hdr.sequence),
1669 		     cmd_size, txq->write_ptr, idx, trans_pcie->cmd_queue);
1670 
1671 	/* start the TFD with the minimum copy bytes */
1672 	tb0_size = min_t(int, copy_size, IWL_FIRST_TB_SIZE);
1673 	memcpy(&txq->first_tb_bufs[idx], &out_cmd->hdr, tb0_size);
1674 	iwl_pcie_txq_build_tfd(trans, txq,
1675 			       iwl_pcie_get_first_tb_dma(txq, idx),
1676 			       tb0_size, true);
1677 
1678 	/* map first command fragment, if any remains */
1679 	if (copy_size > tb0_size) {
1680 		phys_addr = dma_map_single(trans->dev,
1681 					   ((u8 *)&out_cmd->hdr) + tb0_size,
1682 					   copy_size - tb0_size,
1683 					   DMA_TO_DEVICE);
1684 		if (dma_mapping_error(trans->dev, phys_addr)) {
1685 			iwl_pcie_tfd_unmap(trans, out_meta, txq,
1686 					   txq->write_ptr);
1687 			idx = -ENOMEM;
1688 			goto out;
1689 		}
1690 
1691 		iwl_pcie_txq_build_tfd(trans, txq, phys_addr,
1692 				       copy_size - tb0_size, false);
1693 	}
1694 
1695 	/* map the remaining (adjusted) nocopy/dup fragments */
1696 	for (i = 0; i < IWL_MAX_CMD_TBS_PER_TFD; i++) {
1697 		const void *data = cmddata[i];
1698 
1699 		if (!cmdlen[i])
1700 			continue;
1701 		if (!(cmd->dataflags[i] & (IWL_HCMD_DFL_NOCOPY |
1702 					   IWL_HCMD_DFL_DUP)))
1703 			continue;
1704 		if (cmd->dataflags[i] & IWL_HCMD_DFL_DUP)
1705 			data = dup_buf;
1706 		phys_addr = dma_map_single(trans->dev, (void *)data,
1707 					   cmdlen[i], DMA_TO_DEVICE);
1708 		if (dma_mapping_error(trans->dev, phys_addr)) {
1709 			iwl_pcie_tfd_unmap(trans, out_meta, txq,
1710 					   txq->write_ptr);
1711 			idx = -ENOMEM;
1712 			goto out;
1713 		}
1714 
1715 		iwl_pcie_txq_build_tfd(trans, txq, phys_addr, cmdlen[i], false);
1716 	}
1717 
1718 	BUILD_BUG_ON(IWL_TFH_NUM_TBS > sizeof(out_meta->tbs) * BITS_PER_BYTE);
1719 	out_meta->flags = cmd->flags;
1720 	if (WARN_ON_ONCE(txq->entries[idx].free_buf))
1721 		kzfree(txq->entries[idx].free_buf);
1722 	txq->entries[idx].free_buf = dup_buf;
1723 
1724 	trace_iwlwifi_dev_hcmd(trans->dev, cmd, cmd_size, &out_cmd->hdr_wide);
1725 
1726 	/* start timer if queue currently empty */
1727 	if (txq->read_ptr == txq->write_ptr && txq->wd_timeout)
1728 		mod_timer(&txq->stuck_timer, jiffies + txq->wd_timeout);
1729 
1730 	spin_lock_irqsave(&trans_pcie->reg_lock, flags);
1731 	ret = iwl_pcie_set_cmd_in_flight(trans, cmd);
1732 	if (ret < 0) {
1733 		idx = ret;
1734 		spin_unlock_irqrestore(&trans_pcie->reg_lock, flags);
1735 		goto out;
1736 	}
1737 
1738 	/* Increment and update queue's write index */
1739 	txq->write_ptr = iwl_queue_inc_wrap(txq->write_ptr);
1740 	iwl_pcie_txq_inc_wr_ptr(trans, txq);
1741 
1742 	spin_unlock_irqrestore(&trans_pcie->reg_lock, flags);
1743 
1744  out:
1745 	spin_unlock_bh(&txq->lock);
1746  free_dup_buf:
1747 	if (idx < 0)
1748 		kfree(dup_buf);
1749 	return idx;
1750 }
1751 
1752 /*
1753  * iwl_pcie_hcmd_complete - Pull unused buffers off the queue and reclaim them
1754  * @rxb: Rx buffer to reclaim
1755  */
1756 void iwl_pcie_hcmd_complete(struct iwl_trans *trans,
1757 			    struct iwl_rx_cmd_buffer *rxb)
1758 {
1759 	struct iwl_rx_packet *pkt = rxb_addr(rxb);
1760 	u16 sequence = le16_to_cpu(pkt->hdr.sequence);
1761 	u8 group_id = iwl_cmd_groupid(pkt->hdr.group_id);
1762 	u32 cmd_id;
1763 	int txq_id = SEQ_TO_QUEUE(sequence);
1764 	int index = SEQ_TO_INDEX(sequence);
1765 	int cmd_index;
1766 	struct iwl_device_cmd *cmd;
1767 	struct iwl_cmd_meta *meta;
1768 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1769 	struct iwl_txq *txq = &trans_pcie->txq[trans_pcie->cmd_queue];
1770 
1771 	/* If a Tx command is being handled and it isn't in the actual
1772 	 * command queue then there a command routing bug has been introduced
1773 	 * in the queue management code. */
1774 	if (WARN(txq_id != trans_pcie->cmd_queue,
1775 		 "wrong command queue %d (should be %d), sequence 0x%X readp=%d writep=%d\n",
1776 		 txq_id, trans_pcie->cmd_queue, sequence,
1777 		 trans_pcie->txq[trans_pcie->cmd_queue].read_ptr,
1778 		 trans_pcie->txq[trans_pcie->cmd_queue].write_ptr)) {
1779 		iwl_print_hex_error(trans, pkt, 32);
1780 		return;
1781 	}
1782 
1783 	spin_lock_bh(&txq->lock);
1784 
1785 	cmd_index = get_cmd_index(txq, index);
1786 	cmd = txq->entries[cmd_index].cmd;
1787 	meta = &txq->entries[cmd_index].meta;
1788 	cmd_id = iwl_cmd_id(cmd->hdr.cmd, group_id, 0);
1789 
1790 	iwl_pcie_tfd_unmap(trans, meta, txq, index);
1791 
1792 	/* Input error checking is done when commands are added to queue. */
1793 	if (meta->flags & CMD_WANT_SKB) {
1794 		struct page *p = rxb_steal_page(rxb);
1795 
1796 		meta->source->resp_pkt = pkt;
1797 		meta->source->_rx_page_addr = (unsigned long)page_address(p);
1798 		meta->source->_rx_page_order = trans_pcie->rx_page_order;
1799 	}
1800 
1801 	if (meta->flags & CMD_WANT_ASYNC_CALLBACK)
1802 		iwl_op_mode_async_cb(trans->op_mode, cmd);
1803 
1804 	iwl_pcie_cmdq_reclaim(trans, txq_id, index);
1805 
1806 	if (!(meta->flags & CMD_ASYNC)) {
1807 		if (!test_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status)) {
1808 			IWL_WARN(trans,
1809 				 "HCMD_ACTIVE already clear for command %s\n",
1810 				 iwl_get_cmd_string(trans, cmd_id));
1811 		}
1812 		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1813 		IWL_DEBUG_INFO(trans, "Clearing HCMD_ACTIVE for command %s\n",
1814 			       iwl_get_cmd_string(trans, cmd_id));
1815 		wake_up(&trans_pcie->wait_command_queue);
1816 	}
1817 
1818 	if (meta->flags & CMD_MAKE_TRANS_IDLE) {
1819 		IWL_DEBUG_INFO(trans, "complete %s - mark trans as idle\n",
1820 			       iwl_get_cmd_string(trans, cmd->hdr.cmd));
1821 		set_bit(STATUS_TRANS_IDLE, &trans->status);
1822 		wake_up(&trans_pcie->d0i3_waitq);
1823 	}
1824 
1825 	if (meta->flags & CMD_WAKE_UP_TRANS) {
1826 		IWL_DEBUG_INFO(trans, "complete %s - clear trans idle flag\n",
1827 			       iwl_get_cmd_string(trans, cmd->hdr.cmd));
1828 		clear_bit(STATUS_TRANS_IDLE, &trans->status);
1829 		wake_up(&trans_pcie->d0i3_waitq);
1830 	}
1831 
1832 	meta->flags = 0;
1833 
1834 	spin_unlock_bh(&txq->lock);
1835 }
1836 
1837 #define HOST_COMPLETE_TIMEOUT	(2 * HZ)
1838 
1839 static int iwl_pcie_send_hcmd_async(struct iwl_trans *trans,
1840 				    struct iwl_host_cmd *cmd)
1841 {
1842 	int ret;
1843 
1844 	/* An asynchronous command can not expect an SKB to be set. */
1845 	if (WARN_ON(cmd->flags & CMD_WANT_SKB))
1846 		return -EINVAL;
1847 
1848 	ret = iwl_pcie_enqueue_hcmd(trans, cmd);
1849 	if (ret < 0) {
1850 		IWL_ERR(trans,
1851 			"Error sending %s: enqueue_hcmd failed: %d\n",
1852 			iwl_get_cmd_string(trans, cmd->id), ret);
1853 		return ret;
1854 	}
1855 	return 0;
1856 }
1857 
1858 static int iwl_pcie_send_hcmd_sync(struct iwl_trans *trans,
1859 				   struct iwl_host_cmd *cmd)
1860 {
1861 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1862 	int cmd_idx;
1863 	int ret;
1864 
1865 	IWL_DEBUG_INFO(trans, "Attempting to send sync command %s\n",
1866 		       iwl_get_cmd_string(trans, cmd->id));
1867 
1868 	if (WARN(test_and_set_bit(STATUS_SYNC_HCMD_ACTIVE,
1869 				  &trans->status),
1870 		 "Command %s: a command is already active!\n",
1871 		 iwl_get_cmd_string(trans, cmd->id)))
1872 		return -EIO;
1873 
1874 	IWL_DEBUG_INFO(trans, "Setting HCMD_ACTIVE for command %s\n",
1875 		       iwl_get_cmd_string(trans, cmd->id));
1876 
1877 	if (pm_runtime_suspended(&trans_pcie->pci_dev->dev)) {
1878 		ret = wait_event_timeout(trans_pcie->d0i3_waitq,
1879 				 pm_runtime_active(&trans_pcie->pci_dev->dev),
1880 				 msecs_to_jiffies(IWL_TRANS_IDLE_TIMEOUT));
1881 		if (!ret) {
1882 			IWL_ERR(trans, "Timeout exiting D0i3 before hcmd\n");
1883 			return -ETIMEDOUT;
1884 		}
1885 	}
1886 
1887 	cmd_idx = iwl_pcie_enqueue_hcmd(trans, cmd);
1888 	if (cmd_idx < 0) {
1889 		ret = cmd_idx;
1890 		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1891 		IWL_ERR(trans,
1892 			"Error sending %s: enqueue_hcmd failed: %d\n",
1893 			iwl_get_cmd_string(trans, cmd->id), ret);
1894 		return ret;
1895 	}
1896 
1897 	ret = wait_event_timeout(trans_pcie->wait_command_queue,
1898 				 !test_bit(STATUS_SYNC_HCMD_ACTIVE,
1899 					   &trans->status),
1900 				 HOST_COMPLETE_TIMEOUT);
1901 	if (!ret) {
1902 		struct iwl_txq *txq = &trans_pcie->txq[trans_pcie->cmd_queue];
1903 
1904 		IWL_ERR(trans, "Error sending %s: time out after %dms.\n",
1905 			iwl_get_cmd_string(trans, cmd->id),
1906 			jiffies_to_msecs(HOST_COMPLETE_TIMEOUT));
1907 
1908 		IWL_ERR(trans, "Current CMD queue read_ptr %d write_ptr %d\n",
1909 			txq->read_ptr, txq->write_ptr);
1910 
1911 		clear_bit(STATUS_SYNC_HCMD_ACTIVE, &trans->status);
1912 		IWL_DEBUG_INFO(trans, "Clearing HCMD_ACTIVE for command %s\n",
1913 			       iwl_get_cmd_string(trans, cmd->id));
1914 		ret = -ETIMEDOUT;
1915 
1916 		iwl_force_nmi(trans);
1917 		iwl_trans_fw_error(trans);
1918 
1919 		goto cancel;
1920 	}
1921 
1922 	if (test_bit(STATUS_FW_ERROR, &trans->status)) {
1923 		IWL_ERR(trans, "FW error in SYNC CMD %s\n",
1924 			iwl_get_cmd_string(trans, cmd->id));
1925 		dump_stack();
1926 		ret = -EIO;
1927 		goto cancel;
1928 	}
1929 
1930 	if (!(cmd->flags & CMD_SEND_IN_RFKILL) &&
1931 	    test_bit(STATUS_RFKILL, &trans->status)) {
1932 		IWL_DEBUG_RF_KILL(trans, "RFKILL in SYNC CMD... no rsp\n");
1933 		ret = -ERFKILL;
1934 		goto cancel;
1935 	}
1936 
1937 	if ((cmd->flags & CMD_WANT_SKB) && !cmd->resp_pkt) {
1938 		IWL_ERR(trans, "Error: Response NULL in '%s'\n",
1939 			iwl_get_cmd_string(trans, cmd->id));
1940 		ret = -EIO;
1941 		goto cancel;
1942 	}
1943 
1944 	return 0;
1945 
1946 cancel:
1947 	if (cmd->flags & CMD_WANT_SKB) {
1948 		/*
1949 		 * Cancel the CMD_WANT_SKB flag for the cmd in the
1950 		 * TX cmd queue. Otherwise in case the cmd comes
1951 		 * in later, it will possibly set an invalid
1952 		 * address (cmd->meta.source).
1953 		 */
1954 		trans_pcie->txq[trans_pcie->cmd_queue].
1955 			entries[cmd_idx].meta.flags &= ~CMD_WANT_SKB;
1956 	}
1957 
1958 	if (cmd->resp_pkt) {
1959 		iwl_free_resp(cmd);
1960 		cmd->resp_pkt = NULL;
1961 	}
1962 
1963 	return ret;
1964 }
1965 
1966 int iwl_trans_pcie_send_hcmd(struct iwl_trans *trans, struct iwl_host_cmd *cmd)
1967 {
1968 	if (!(cmd->flags & CMD_SEND_IN_RFKILL) &&
1969 	    test_bit(STATUS_RFKILL, &trans->status)) {
1970 		IWL_DEBUG_RF_KILL(trans, "Dropping CMD 0x%x: RF KILL\n",
1971 				  cmd->id);
1972 		return -ERFKILL;
1973 	}
1974 
1975 	if (cmd->flags & CMD_ASYNC)
1976 		return iwl_pcie_send_hcmd_async(trans, cmd);
1977 
1978 	/* We still can fail on RFKILL that can be asserted while we wait */
1979 	return iwl_pcie_send_hcmd_sync(trans, cmd);
1980 }
1981 
1982 static int iwl_fill_data_tbs(struct iwl_trans *trans, struct sk_buff *skb,
1983 			     struct iwl_txq *txq, u8 hdr_len,
1984 			     struct iwl_cmd_meta *out_meta,
1985 			     struct iwl_device_cmd *dev_cmd, u16 tb1_len)
1986 {
1987 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
1988 	u16 tb2_len;
1989 	int i;
1990 
1991 	/*
1992 	 * Set up TFD's third entry to point directly to remainder
1993 	 * of skb's head, if any
1994 	 */
1995 	tb2_len = skb_headlen(skb) - hdr_len;
1996 
1997 	if (tb2_len > 0) {
1998 		dma_addr_t tb2_phys = dma_map_single(trans->dev,
1999 						     skb->data + hdr_len,
2000 						     tb2_len, DMA_TO_DEVICE);
2001 		if (unlikely(dma_mapping_error(trans->dev, tb2_phys))) {
2002 			iwl_pcie_tfd_unmap(trans, out_meta, txq,
2003 					   txq->write_ptr);
2004 			return -EINVAL;
2005 		}
2006 		iwl_pcie_txq_build_tfd(trans, txq, tb2_phys, tb2_len, false);
2007 	}
2008 
2009 	/* set up the remaining entries to point to the data */
2010 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2011 		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2012 		dma_addr_t tb_phys;
2013 		int tb_idx;
2014 
2015 		if (!skb_frag_size(frag))
2016 			continue;
2017 
2018 		tb_phys = skb_frag_dma_map(trans->dev, frag, 0,
2019 					   skb_frag_size(frag), DMA_TO_DEVICE);
2020 
2021 		if (unlikely(dma_mapping_error(trans->dev, tb_phys))) {
2022 			iwl_pcie_tfd_unmap(trans, out_meta, txq,
2023 					   txq->write_ptr);
2024 			return -EINVAL;
2025 		}
2026 		tb_idx = iwl_pcie_txq_build_tfd(trans, txq, tb_phys,
2027 						skb_frag_size(frag), false);
2028 
2029 		out_meta->tbs |= BIT(tb_idx);
2030 	}
2031 
2032 	trace_iwlwifi_dev_tx(trans->dev, skb,
2033 			     iwl_pcie_get_tfd(trans_pcie, txq, txq->write_ptr),
2034 			     trans_pcie->tfd_size,
2035 			     &dev_cmd->hdr, IWL_FIRST_TB_SIZE + tb1_len,
2036 			     skb->data + hdr_len, tb2_len);
2037 	trace_iwlwifi_dev_tx_data(trans->dev, skb,
2038 				  hdr_len, skb->len - hdr_len);
2039 	return 0;
2040 }
2041 
2042 #ifdef CONFIG_INET
2043 static struct iwl_tso_hdr_page *
2044 get_page_hdr(struct iwl_trans *trans, size_t len)
2045 {
2046 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2047 	struct iwl_tso_hdr_page *p = this_cpu_ptr(trans_pcie->tso_hdr_page);
2048 
2049 	if (!p->page)
2050 		goto alloc;
2051 
2052 	/* enough room on this page */
2053 	if (p->pos + len < (u8 *)page_address(p->page) + PAGE_SIZE)
2054 		return p;
2055 
2056 	/* We don't have enough room on this page, get a new one. */
2057 	__free_page(p->page);
2058 
2059 alloc:
2060 	p->page = alloc_page(GFP_ATOMIC);
2061 	if (!p->page)
2062 		return NULL;
2063 	p->pos = page_address(p->page);
2064 	return p;
2065 }
2066 
2067 static void iwl_compute_pseudo_hdr_csum(void *iph, struct tcphdr *tcph,
2068 					bool ipv6, unsigned int len)
2069 {
2070 	if (ipv6) {
2071 		struct ipv6hdr *iphv6 = iph;
2072 
2073 		tcph->check = ~csum_ipv6_magic(&iphv6->saddr, &iphv6->daddr,
2074 					       len + tcph->doff * 4,
2075 					       IPPROTO_TCP, 0);
2076 	} else {
2077 		struct iphdr *iphv4 = iph;
2078 
2079 		ip_send_check(iphv4);
2080 		tcph->check = ~csum_tcpudp_magic(iphv4->saddr, iphv4->daddr,
2081 						 len + tcph->doff * 4,
2082 						 IPPROTO_TCP, 0);
2083 	}
2084 }
2085 
2086 static int iwl_fill_data_tbs_amsdu(struct iwl_trans *trans, struct sk_buff *skb,
2087 				   struct iwl_txq *txq, u8 hdr_len,
2088 				   struct iwl_cmd_meta *out_meta,
2089 				   struct iwl_device_cmd *dev_cmd, u16 tb1_len)
2090 {
2091 	struct iwl_trans_pcie *trans_pcie = txq->trans_pcie;
2092 	struct ieee80211_hdr *hdr = (void *)skb->data;
2093 	unsigned int snap_ip_tcp_hdrlen, ip_hdrlen, total_len, hdr_room;
2094 	unsigned int mss = skb_shinfo(skb)->gso_size;
2095 	u16 length, iv_len, amsdu_pad;
2096 	u8 *start_hdr;
2097 	struct iwl_tso_hdr_page *hdr_page;
2098 	struct page **page_ptr;
2099 	int ret;
2100 	struct tso_t tso;
2101 
2102 	/* if the packet is protected, then it must be CCMP or GCMP */
2103 	BUILD_BUG_ON(IEEE80211_CCMP_HDR_LEN != IEEE80211_GCMP_HDR_LEN);
2104 	iv_len = ieee80211_has_protected(hdr->frame_control) ?
2105 		IEEE80211_CCMP_HDR_LEN : 0;
2106 
2107 	trace_iwlwifi_dev_tx(trans->dev, skb,
2108 			     iwl_pcie_get_tfd(trans_pcie, txq, txq->write_ptr),
2109 			     trans_pcie->tfd_size,
2110 			     &dev_cmd->hdr, IWL_FIRST_TB_SIZE + tb1_len,
2111 			     NULL, 0);
2112 
2113 	ip_hdrlen = skb_transport_header(skb) - skb_network_header(skb);
2114 	snap_ip_tcp_hdrlen = 8 + ip_hdrlen + tcp_hdrlen(skb);
2115 	total_len = skb->len - snap_ip_tcp_hdrlen - hdr_len - iv_len;
2116 	amsdu_pad = 0;
2117 
2118 	/* total amount of header we may need for this A-MSDU */
2119 	hdr_room = DIV_ROUND_UP(total_len, mss) *
2120 		(3 + snap_ip_tcp_hdrlen + sizeof(struct ethhdr)) + iv_len;
2121 
2122 	/* Our device supports 9 segments at most, it will fit in 1 page */
2123 	hdr_page = get_page_hdr(trans, hdr_room);
2124 	if (!hdr_page)
2125 		return -ENOMEM;
2126 
2127 	get_page(hdr_page->page);
2128 	start_hdr = hdr_page->pos;
2129 	page_ptr = (void *)((u8 *)skb->cb + trans_pcie->page_offs);
2130 	*page_ptr = hdr_page->page;
2131 	memcpy(hdr_page->pos, skb->data + hdr_len, iv_len);
2132 	hdr_page->pos += iv_len;
2133 
2134 	/*
2135 	 * Pull the ieee80211 header + IV to be able to use TSO core,
2136 	 * we will restore it for the tx_status flow.
2137 	 */
2138 	skb_pull(skb, hdr_len + iv_len);
2139 
2140 	tso_start(skb, &tso);
2141 
2142 	while (total_len) {
2143 		/* this is the data left for this subframe */
2144 		unsigned int data_left =
2145 			min_t(unsigned int, mss, total_len);
2146 		struct sk_buff *csum_skb = NULL;
2147 		unsigned int hdr_tb_len;
2148 		dma_addr_t hdr_tb_phys;
2149 		struct tcphdr *tcph;
2150 		u8 *iph;
2151 
2152 		total_len -= data_left;
2153 
2154 		memset(hdr_page->pos, 0, amsdu_pad);
2155 		hdr_page->pos += amsdu_pad;
2156 		amsdu_pad = (4 - (sizeof(struct ethhdr) + snap_ip_tcp_hdrlen +
2157 				  data_left)) & 0x3;
2158 		ether_addr_copy(hdr_page->pos, ieee80211_get_DA(hdr));
2159 		hdr_page->pos += ETH_ALEN;
2160 		ether_addr_copy(hdr_page->pos, ieee80211_get_SA(hdr));
2161 		hdr_page->pos += ETH_ALEN;
2162 
2163 		length = snap_ip_tcp_hdrlen + data_left;
2164 		*((__be16 *)hdr_page->pos) = cpu_to_be16(length);
2165 		hdr_page->pos += sizeof(length);
2166 
2167 		/*
2168 		 * This will copy the SNAP as well which will be considered
2169 		 * as MAC header.
2170 		 */
2171 		tso_build_hdr(skb, hdr_page->pos, &tso, data_left, !total_len);
2172 		iph = hdr_page->pos + 8;
2173 		tcph = (void *)(iph + ip_hdrlen);
2174 
2175 		/* For testing on current hardware only */
2176 		if (trans_pcie->sw_csum_tx) {
2177 			csum_skb = alloc_skb(data_left + tcp_hdrlen(skb),
2178 					     GFP_ATOMIC);
2179 			if (!csum_skb) {
2180 				ret = -ENOMEM;
2181 				goto out_unmap;
2182 			}
2183 
2184 			iwl_compute_pseudo_hdr_csum(iph, tcph,
2185 						    skb->protocol ==
2186 							htons(ETH_P_IPV6),
2187 						    data_left);
2188 
2189 			memcpy(skb_put(csum_skb, tcp_hdrlen(skb)),
2190 			       tcph, tcp_hdrlen(skb));
2191 			skb_set_transport_header(csum_skb, 0);
2192 			csum_skb->csum_start =
2193 				(unsigned char *)tcp_hdr(csum_skb) -
2194 						 csum_skb->head;
2195 		}
2196 
2197 		hdr_page->pos += snap_ip_tcp_hdrlen;
2198 
2199 		hdr_tb_len = hdr_page->pos - start_hdr;
2200 		hdr_tb_phys = dma_map_single(trans->dev, start_hdr,
2201 					     hdr_tb_len, DMA_TO_DEVICE);
2202 		if (unlikely(dma_mapping_error(trans->dev, hdr_tb_phys))) {
2203 			dev_kfree_skb(csum_skb);
2204 			ret = -EINVAL;
2205 			goto out_unmap;
2206 		}
2207 		iwl_pcie_txq_build_tfd(trans, txq, hdr_tb_phys,
2208 				       hdr_tb_len, false);
2209 		trace_iwlwifi_dev_tx_tso_chunk(trans->dev, start_hdr,
2210 					       hdr_tb_len);
2211 
2212 		/* prepare the start_hdr for the next subframe */
2213 		start_hdr = hdr_page->pos;
2214 
2215 		/* put the payload */
2216 		while (data_left) {
2217 			unsigned int size = min_t(unsigned int, tso.size,
2218 						  data_left);
2219 			dma_addr_t tb_phys;
2220 
2221 			if (trans_pcie->sw_csum_tx)
2222 				memcpy(skb_put(csum_skb, size), tso.data, size);
2223 
2224 			tb_phys = dma_map_single(trans->dev, tso.data,
2225 						 size, DMA_TO_DEVICE);
2226 			if (unlikely(dma_mapping_error(trans->dev, tb_phys))) {
2227 				dev_kfree_skb(csum_skb);
2228 				ret = -EINVAL;
2229 				goto out_unmap;
2230 			}
2231 
2232 			iwl_pcie_txq_build_tfd(trans, txq, tb_phys,
2233 					       size, false);
2234 			trace_iwlwifi_dev_tx_tso_chunk(trans->dev, tso.data,
2235 						       size);
2236 
2237 			data_left -= size;
2238 			tso_build_data(skb, &tso, size);
2239 		}
2240 
2241 		/* For testing on early hardware only */
2242 		if (trans_pcie->sw_csum_tx) {
2243 			__wsum csum;
2244 
2245 			csum = skb_checksum(csum_skb,
2246 					    skb_checksum_start_offset(csum_skb),
2247 					    csum_skb->len -
2248 					    skb_checksum_start_offset(csum_skb),
2249 					    0);
2250 			dev_kfree_skb(csum_skb);
2251 			dma_sync_single_for_cpu(trans->dev, hdr_tb_phys,
2252 						hdr_tb_len, DMA_TO_DEVICE);
2253 			tcph->check = csum_fold(csum);
2254 			dma_sync_single_for_device(trans->dev, hdr_tb_phys,
2255 						   hdr_tb_len, DMA_TO_DEVICE);
2256 		}
2257 	}
2258 
2259 	/* re -add the WiFi header and IV */
2260 	skb_push(skb, hdr_len + iv_len);
2261 
2262 	return 0;
2263 
2264 out_unmap:
2265 	iwl_pcie_tfd_unmap(trans, out_meta, txq, txq->write_ptr);
2266 	return ret;
2267 }
2268 #else /* CONFIG_INET */
2269 static int iwl_fill_data_tbs_amsdu(struct iwl_trans *trans, struct sk_buff *skb,
2270 				   struct iwl_txq *txq, u8 hdr_len,
2271 				   struct iwl_cmd_meta *out_meta,
2272 				   struct iwl_device_cmd *dev_cmd, u16 tb1_len)
2273 {
2274 	/* No A-MSDU without CONFIG_INET */
2275 	WARN_ON(1);
2276 
2277 	return -1;
2278 }
2279 #endif /* CONFIG_INET */
2280 
2281 int iwl_trans_pcie_tx(struct iwl_trans *trans, struct sk_buff *skb,
2282 		      struct iwl_device_cmd *dev_cmd, int txq_id)
2283 {
2284 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
2285 	struct ieee80211_hdr *hdr;
2286 	struct iwl_tx_cmd *tx_cmd = (struct iwl_tx_cmd *)dev_cmd->payload;
2287 	struct iwl_cmd_meta *out_meta;
2288 	struct iwl_txq *txq;
2289 	dma_addr_t tb0_phys, tb1_phys, scratch_phys;
2290 	void *tb1_addr;
2291 	void *tfd;
2292 	u16 len, tb1_len;
2293 	bool wait_write_ptr;
2294 	__le16 fc;
2295 	u8 hdr_len;
2296 	u16 wifi_seq;
2297 	bool amsdu;
2298 
2299 	txq = &trans_pcie->txq[txq_id];
2300 
2301 	if (WARN_ONCE(!test_bit(txq_id, trans_pcie->queue_used),
2302 		      "TX on unused queue %d\n", txq_id))
2303 		return -EINVAL;
2304 
2305 	if (unlikely(trans_pcie->sw_csum_tx &&
2306 		     skb->ip_summed == CHECKSUM_PARTIAL)) {
2307 		int offs = skb_checksum_start_offset(skb);
2308 		int csum_offs = offs + skb->csum_offset;
2309 		__wsum csum;
2310 
2311 		if (skb_ensure_writable(skb, csum_offs + sizeof(__sum16)))
2312 			return -1;
2313 
2314 		csum = skb_checksum(skb, offs, skb->len - offs, 0);
2315 		*(__sum16 *)(skb->data + csum_offs) = csum_fold(csum);
2316 
2317 		skb->ip_summed = CHECKSUM_UNNECESSARY;
2318 	}
2319 
2320 	if (skb_is_nonlinear(skb) &&
2321 	    skb_shinfo(skb)->nr_frags > IWL_PCIE_MAX_FRAGS(trans_pcie) &&
2322 	    __skb_linearize(skb))
2323 		return -ENOMEM;
2324 
2325 	/* mac80211 always puts the full header into the SKB's head,
2326 	 * so there's no need to check if it's readable there
2327 	 */
2328 	hdr = (struct ieee80211_hdr *)skb->data;
2329 	fc = hdr->frame_control;
2330 	hdr_len = ieee80211_hdrlen(fc);
2331 
2332 	spin_lock(&txq->lock);
2333 
2334 	if (iwl_queue_space(txq) < txq->high_mark) {
2335 		iwl_stop_queue(trans, txq);
2336 
2337 		/* don't put the packet on the ring, if there is no room */
2338 		if (unlikely(iwl_queue_space(txq) < 3)) {
2339 			struct iwl_device_cmd **dev_cmd_ptr;
2340 
2341 			dev_cmd_ptr = (void *)((u8 *)skb->cb +
2342 					       trans_pcie->dev_cmd_offs);
2343 
2344 			*dev_cmd_ptr = dev_cmd;
2345 			__skb_queue_tail(&txq->overflow_q, skb);
2346 
2347 			spin_unlock(&txq->lock);
2348 			return 0;
2349 		}
2350 	}
2351 
2352 	/* In AGG mode, the index in the ring must correspond to the WiFi
2353 	 * sequence number. This is a HW requirements to help the SCD to parse
2354 	 * the BA.
2355 	 * Check here that the packets are in the right place on the ring.
2356 	 */
2357 	wifi_seq = IEEE80211_SEQ_TO_SN(le16_to_cpu(hdr->seq_ctrl));
2358 	WARN_ONCE(txq->ampdu &&
2359 		  (wifi_seq & 0xff) != txq->write_ptr,
2360 		  "Q: %d WiFi Seq %d tfdNum %d",
2361 		  txq_id, wifi_seq, txq->write_ptr);
2362 
2363 	/* Set up driver data for this TFD */
2364 	txq->entries[txq->write_ptr].skb = skb;
2365 	txq->entries[txq->write_ptr].cmd = dev_cmd;
2366 
2367 	dev_cmd->hdr.sequence =
2368 		cpu_to_le16((u16)(QUEUE_TO_SEQ(txq_id) |
2369 			    INDEX_TO_SEQ(txq->write_ptr)));
2370 
2371 	tb0_phys = iwl_pcie_get_first_tb_dma(txq, txq->write_ptr);
2372 	scratch_phys = tb0_phys + sizeof(struct iwl_cmd_header) +
2373 		       offsetof(struct iwl_tx_cmd, scratch);
2374 
2375 	tx_cmd->dram_lsb_ptr = cpu_to_le32(scratch_phys);
2376 	tx_cmd->dram_msb_ptr = iwl_get_dma_hi_addr(scratch_phys);
2377 
2378 	/* Set up first empty entry in queue's array of Tx/cmd buffers */
2379 	out_meta = &txq->entries[txq->write_ptr].meta;
2380 	out_meta->flags = 0;
2381 
2382 	/*
2383 	 * The second TB (tb1) points to the remainder of the TX command
2384 	 * and the 802.11 header - dword aligned size
2385 	 * (This calculation modifies the TX command, so do it before the
2386 	 * setup of the first TB)
2387 	 */
2388 	len = sizeof(struct iwl_tx_cmd) + sizeof(struct iwl_cmd_header) +
2389 	      hdr_len - IWL_FIRST_TB_SIZE;
2390 	/* do not align A-MSDU to dword as the subframe header aligns it */
2391 	amsdu = ieee80211_is_data_qos(fc) &&
2392 		(*ieee80211_get_qos_ctl(hdr) &
2393 		 IEEE80211_QOS_CTL_A_MSDU_PRESENT);
2394 	if (trans_pcie->sw_csum_tx || !amsdu) {
2395 		tb1_len = ALIGN(len, 4);
2396 		/* Tell NIC about any 2-byte padding after MAC header */
2397 		if (tb1_len != len)
2398 			tx_cmd->tx_flags |= TX_CMD_FLG_MH_PAD_MSK;
2399 	} else {
2400 		tb1_len = len;
2401 	}
2402 
2403 	/* The first TB points to bi-directional DMA data */
2404 	memcpy(&txq->first_tb_bufs[txq->write_ptr], &dev_cmd->hdr,
2405 	       IWL_FIRST_TB_SIZE);
2406 	iwl_pcie_txq_build_tfd(trans, txq, tb0_phys,
2407 			       IWL_FIRST_TB_SIZE, true);
2408 
2409 	/* there must be data left over for TB1 or this code must be changed */
2410 	BUILD_BUG_ON(sizeof(struct iwl_tx_cmd) < IWL_FIRST_TB_SIZE);
2411 
2412 	/* map the data for TB1 */
2413 	tb1_addr = ((u8 *)&dev_cmd->hdr) + IWL_FIRST_TB_SIZE;
2414 	tb1_phys = dma_map_single(trans->dev, tb1_addr, tb1_len, DMA_TO_DEVICE);
2415 	if (unlikely(dma_mapping_error(trans->dev, tb1_phys)))
2416 		goto out_err;
2417 	iwl_pcie_txq_build_tfd(trans, txq, tb1_phys, tb1_len, false);
2418 
2419 	if (amsdu) {
2420 		if (unlikely(iwl_fill_data_tbs_amsdu(trans, skb, txq, hdr_len,
2421 						     out_meta, dev_cmd,
2422 						     tb1_len)))
2423 			goto out_err;
2424 	} else if (unlikely(iwl_fill_data_tbs(trans, skb, txq, hdr_len,
2425 				       out_meta, dev_cmd, tb1_len))) {
2426 		goto out_err;
2427 	}
2428 
2429 	tfd = iwl_pcie_get_tfd(trans_pcie, txq, txq->write_ptr);
2430 	/* Set up entry for this TFD in Tx byte-count array */
2431 	iwl_pcie_txq_update_byte_cnt_tbl(trans, txq, le16_to_cpu(tx_cmd->len),
2432 					 iwl_pcie_tfd_get_num_tbs(trans, tfd));
2433 
2434 	wait_write_ptr = ieee80211_has_morefrags(fc);
2435 
2436 	/* start timer if queue currently empty */
2437 	if (txq->read_ptr == txq->write_ptr) {
2438 		if (txq->wd_timeout) {
2439 			/*
2440 			 * If the TXQ is active, then set the timer, if not,
2441 			 * set the timer in remainder so that the timer will
2442 			 * be armed with the right value when the station will
2443 			 * wake up.
2444 			 */
2445 			if (!txq->frozen)
2446 				mod_timer(&txq->stuck_timer,
2447 					  jiffies + txq->wd_timeout);
2448 			else
2449 				txq->frozen_expiry_remainder = txq->wd_timeout;
2450 		}
2451 		IWL_DEBUG_RPM(trans, "Q: %d first tx - take ref\n", txq->id);
2452 		iwl_trans_ref(trans);
2453 	}
2454 
2455 	/* Tell device the write index *just past* this latest filled TFD */
2456 	txq->write_ptr = iwl_queue_inc_wrap(txq->write_ptr);
2457 	if (!wait_write_ptr)
2458 		iwl_pcie_txq_inc_wr_ptr(trans, txq);
2459 
2460 	/*
2461 	 * At this point the frame is "transmitted" successfully
2462 	 * and we will get a TX status notification eventually.
2463 	 */
2464 	spin_unlock(&txq->lock);
2465 	return 0;
2466 out_err:
2467 	spin_unlock(&txq->lock);
2468 	return -1;
2469 }
2470