xref: /dpdk/drivers/net/sfc/sfc_tx.c (revision 89f0711f9ddfb5822da9d34f384b92f72a61c4dc)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  *
3  * Copyright (c) 2016-2018 Solarflare Communications Inc.
4  * All rights reserved.
5  *
6  * This software was jointly developed between OKTET Labs (under contract
7  * for Solarflare) and Solarflare Communications, Inc.
8  */
9 
10 #include "sfc.h"
11 #include "sfc_debug.h"
12 #include "sfc_log.h"
13 #include "sfc_ev.h"
14 #include "sfc_tx.h"
15 #include "sfc_tweak.h"
16 #include "sfc_kvargs.h"
17 
18 /*
19  * Maximum number of TX queue flush attempts in case of
20  * failure or flush timeout
21  */
22 #define SFC_TX_QFLUSH_ATTEMPTS		(3)
23 
24 /*
25  * Time to wait between event queue polling attempts when waiting for TX
26  * queue flush done or flush failed events
27  */
28 #define SFC_TX_QFLUSH_POLL_WAIT_MS	(1)
29 
30 /*
31  * Maximum number of event queue polling attempts when waiting for TX queue
32  * flush done or flush failed events; it defines TX queue flush attempt timeout
33  * together with SFC_TX_QFLUSH_POLL_WAIT_MS
34  */
35 #define SFC_TX_QFLUSH_POLL_ATTEMPTS	(2000)
36 
37 uint64_t
38 sfc_tx_get_dev_offload_caps(struct sfc_adapter *sa)
39 {
40 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
41 	uint64_t caps = 0;
42 
43 	if ((sa->dp_tx->features & SFC_DP_TX_FEAT_VLAN_INSERT) &&
44 	    encp->enc_hw_tx_insert_vlan_enabled)
45 		caps |= DEV_TX_OFFLOAD_VLAN_INSERT;
46 
47 	if (sa->dp_tx->features & SFC_DP_TX_FEAT_MULTI_SEG)
48 		caps |= DEV_TX_OFFLOAD_MULTI_SEGS;
49 
50 	if ((~sa->dp_tx->features & SFC_DP_TX_FEAT_MULTI_POOL) &&
51 	    (~sa->dp_tx->features & SFC_DP_TX_FEAT_REFCNT))
52 		caps |= DEV_TX_OFFLOAD_MBUF_FAST_FREE;
53 
54 	return caps;
55 }
56 
57 uint64_t
58 sfc_tx_get_queue_offload_caps(struct sfc_adapter *sa)
59 {
60 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
61 	uint64_t caps = 0;
62 
63 	caps |= DEV_TX_OFFLOAD_IPV4_CKSUM;
64 	caps |= DEV_TX_OFFLOAD_UDP_CKSUM;
65 	caps |= DEV_TX_OFFLOAD_TCP_CKSUM;
66 
67 	if (encp->enc_tunnel_encapsulations_supported)
68 		caps |= DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM;
69 
70 	if (sa->tso)
71 		caps |= DEV_TX_OFFLOAD_TCP_TSO;
72 
73 	return caps;
74 }
75 
76 static void
77 sfc_tx_log_offloads(struct sfc_adapter *sa, const char *offload_group,
78 		    const char *verdict, uint64_t offloads)
79 {
80 	unsigned long long bit;
81 
82 	while ((bit = __builtin_ffsll(offloads)) != 0) {
83 		uint64_t flag = (1ULL << --bit);
84 
85 		sfc_err(sa, "Tx %s offload %s %s", offload_group,
86 			rte_eth_dev_tx_offload_name(flag), verdict);
87 
88 		offloads &= ~flag;
89 	}
90 }
91 
92 static int
93 sfc_tx_queue_offload_mismatch(struct sfc_adapter *sa, uint64_t requested)
94 {
95 	uint64_t mandatory = sa->eth_dev->data->dev_conf.txmode.offloads;
96 	uint64_t supported = sfc_tx_get_dev_offload_caps(sa) |
97 			     sfc_tx_get_queue_offload_caps(sa);
98 	uint64_t rejected = requested & ~supported;
99 	uint64_t missing = (requested & mandatory) ^ mandatory;
100 	boolean_t mismatch = B_FALSE;
101 
102 	if (rejected) {
103 		sfc_tx_log_offloads(sa, "queue", "is unsupported", rejected);
104 		mismatch = B_TRUE;
105 	}
106 
107 	if (missing) {
108 		sfc_tx_log_offloads(sa, "queue", "must be set", missing);
109 		mismatch = B_TRUE;
110 	}
111 
112 	return mismatch;
113 }
114 
115 static int
116 sfc_tx_qcheck_conf(struct sfc_adapter *sa, unsigned int txq_max_fill_level,
117 		   const struct rte_eth_txconf *tx_conf)
118 {
119 	int rc = 0;
120 
121 	if (tx_conf->tx_rs_thresh != 0) {
122 		sfc_err(sa, "RS bit in transmit descriptor is not supported");
123 		rc = EINVAL;
124 	}
125 
126 	if (tx_conf->tx_free_thresh > txq_max_fill_level) {
127 		sfc_err(sa,
128 			"TxQ free threshold too large: %u vs maximum %u",
129 			tx_conf->tx_free_thresh, txq_max_fill_level);
130 		rc = EINVAL;
131 	}
132 
133 	if (tx_conf->tx_thresh.pthresh != 0 ||
134 	    tx_conf->tx_thresh.hthresh != 0 ||
135 	    tx_conf->tx_thresh.wthresh != 0) {
136 		sfc_warn(sa,
137 			"prefetch/host/writeback thresholds are not supported");
138 	}
139 
140 	/* We either perform both TCP and UDP offload, or no offload at all */
141 	if (((tx_conf->offloads & DEV_TX_OFFLOAD_TCP_CKSUM) == 0) !=
142 	    ((tx_conf->offloads & DEV_TX_OFFLOAD_UDP_CKSUM) == 0)) {
143 		sfc_err(sa, "TCP and UDP offloads can't be set independently");
144 		rc = EINVAL;
145 	}
146 
147 	if (sfc_tx_queue_offload_mismatch(sa, tx_conf->offloads))
148 		rc = EINVAL;
149 
150 	return rc;
151 }
152 
153 void
154 sfc_tx_qflush_done(struct sfc_txq *txq)
155 {
156 	txq->state |= SFC_TXQ_FLUSHED;
157 	txq->state &= ~SFC_TXQ_FLUSHING;
158 }
159 
160 int
161 sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
162 	     uint16_t nb_tx_desc, unsigned int socket_id,
163 	     const struct rte_eth_txconf *tx_conf)
164 {
165 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
166 	unsigned int txq_entries;
167 	unsigned int evq_entries;
168 	unsigned int txq_max_fill_level;
169 	struct sfc_txq_info *txq_info;
170 	struct sfc_evq *evq;
171 	struct sfc_txq *txq;
172 	int rc = 0;
173 	struct sfc_dp_tx_qcreate_info info;
174 
175 	sfc_log_init(sa, "TxQ = %u", sw_index);
176 
177 	rc = sa->dp_tx->qsize_up_rings(nb_tx_desc, &txq_entries, &evq_entries,
178 				       &txq_max_fill_level);
179 	if (rc != 0)
180 		goto fail_size_up_rings;
181 	SFC_ASSERT(txq_entries >= EFX_TXQ_MINNDESCS);
182 	SFC_ASSERT(txq_entries <= sa->txq_max_entries);
183 	SFC_ASSERT(txq_entries >= nb_tx_desc);
184 	SFC_ASSERT(txq_max_fill_level <= nb_tx_desc);
185 
186 	rc = sfc_tx_qcheck_conf(sa, txq_max_fill_level, tx_conf);
187 	if (rc != 0)
188 		goto fail_bad_conf;
189 
190 	SFC_ASSERT(sw_index < sa->txq_count);
191 	txq_info = &sa->txq_info[sw_index];
192 
193 	txq_info->entries = txq_entries;
194 
195 	rc = sfc_ev_qinit(sa, SFC_EVQ_TYPE_TX, sw_index,
196 			  evq_entries, socket_id, &evq);
197 	if (rc != 0)
198 		goto fail_ev_qinit;
199 
200 	rc = ENOMEM;
201 	txq = rte_zmalloc_socket("sfc-txq", sizeof(*txq), 0, socket_id);
202 	if (txq == NULL)
203 		goto fail_txq_alloc;
204 
205 	txq_info->txq = txq;
206 
207 	txq->hw_index = sw_index;
208 	txq->evq = evq;
209 	txq->free_thresh =
210 		(tx_conf->tx_free_thresh) ? tx_conf->tx_free_thresh :
211 		SFC_TX_DEFAULT_FREE_THRESH;
212 	txq->flags = tx_conf->txq_flags;
213 	txq->offloads = tx_conf->offloads;
214 
215 	rc = sfc_dma_alloc(sa, "txq", sw_index, EFX_TXQ_SIZE(txq_info->entries),
216 			   socket_id, &txq->mem);
217 	if (rc != 0)
218 		goto fail_dma_alloc;
219 
220 	memset(&info, 0, sizeof(info));
221 	info.max_fill_level = txq_max_fill_level;
222 	info.free_thresh = txq->free_thresh;
223 	info.flags = tx_conf->txq_flags;
224 	info.offloads = tx_conf->offloads;
225 	info.txq_entries = txq_info->entries;
226 	info.dma_desc_size_max = encp->enc_tx_dma_desc_size_max;
227 	info.txq_hw_ring = txq->mem.esm_base;
228 	info.evq_entries = evq_entries;
229 	info.evq_hw_ring = evq->mem.esm_base;
230 	info.hw_index = txq->hw_index;
231 	info.mem_bar = sa->mem_bar.esb_base;
232 
233 	rc = sa->dp_tx->qcreate(sa->eth_dev->data->port_id, sw_index,
234 				&RTE_ETH_DEV_TO_PCI(sa->eth_dev)->addr,
235 				socket_id, &info, &txq->dp);
236 	if (rc != 0)
237 		goto fail_dp_tx_qinit;
238 
239 	evq->dp_txq = txq->dp;
240 
241 	txq->state = SFC_TXQ_INITIALIZED;
242 
243 	txq_info->deferred_start = (tx_conf->tx_deferred_start != 0);
244 
245 	return 0;
246 
247 fail_dp_tx_qinit:
248 	sfc_dma_free(sa, &txq->mem);
249 
250 fail_dma_alloc:
251 	txq_info->txq = NULL;
252 	rte_free(txq);
253 
254 fail_txq_alloc:
255 	sfc_ev_qfini(evq);
256 
257 fail_ev_qinit:
258 	txq_info->entries = 0;
259 
260 fail_bad_conf:
261 fail_size_up_rings:
262 	sfc_log_init(sa, "failed (TxQ = %u, rc = %d)", sw_index, rc);
263 	return rc;
264 }
265 
266 void
267 sfc_tx_qfini(struct sfc_adapter *sa, unsigned int sw_index)
268 {
269 	struct sfc_txq_info *txq_info;
270 	struct sfc_txq *txq;
271 
272 	sfc_log_init(sa, "TxQ = %u", sw_index);
273 
274 	SFC_ASSERT(sw_index < sa->txq_count);
275 	txq_info = &sa->txq_info[sw_index];
276 
277 	txq = txq_info->txq;
278 	SFC_ASSERT(txq != NULL);
279 	SFC_ASSERT(txq->state == SFC_TXQ_INITIALIZED);
280 
281 	sa->dp_tx->qdestroy(txq->dp);
282 	txq->dp = NULL;
283 
284 	txq_info->txq = NULL;
285 	txq_info->entries = 0;
286 
287 	sfc_dma_free(sa, &txq->mem);
288 
289 	sfc_ev_qfini(txq->evq);
290 	txq->evq = NULL;
291 
292 	rte_free(txq);
293 }
294 
295 static int
296 sfc_tx_qinit_info(struct sfc_adapter *sa, unsigned int sw_index)
297 {
298 	sfc_log_init(sa, "TxQ = %u", sw_index);
299 
300 	return 0;
301 }
302 
303 static int
304 sfc_tx_check_mode(struct sfc_adapter *sa, const struct rte_eth_txmode *txmode)
305 {
306 	uint64_t offloads_supported = sfc_tx_get_dev_offload_caps(sa) |
307 				      sfc_tx_get_queue_offload_caps(sa);
308 	uint64_t offloads_rejected = txmode->offloads & ~offloads_supported;
309 	int rc = 0;
310 
311 	switch (txmode->mq_mode) {
312 	case ETH_MQ_TX_NONE:
313 		break;
314 	default:
315 		sfc_err(sa, "Tx multi-queue mode %u not supported",
316 			txmode->mq_mode);
317 		rc = EINVAL;
318 	}
319 
320 	/*
321 	 * These features are claimed to be i40e-specific,
322 	 * but it does make sense to double-check their absence
323 	 */
324 	if (txmode->hw_vlan_reject_tagged) {
325 		sfc_err(sa, "Rejecting tagged packets not supported");
326 		rc = EINVAL;
327 	}
328 
329 	if (txmode->hw_vlan_reject_untagged) {
330 		sfc_err(sa, "Rejecting untagged packets not supported");
331 		rc = EINVAL;
332 	}
333 
334 	if (txmode->hw_vlan_insert_pvid) {
335 		sfc_err(sa, "Port-based VLAN insertion not supported");
336 		rc = EINVAL;
337 	}
338 
339 	if (offloads_rejected) {
340 		sfc_tx_log_offloads(sa, "device", "is unsupported",
341 				    offloads_rejected);
342 		rc = EINVAL;
343 	}
344 
345 	return rc;
346 }
347 
348 /**
349  * Destroy excess queues that are no longer needed after reconfiguration
350  * or complete close.
351  */
352 static void
353 sfc_tx_fini_queues(struct sfc_adapter *sa, unsigned int nb_tx_queues)
354 {
355 	int sw_index;
356 
357 	SFC_ASSERT(nb_tx_queues <= sa->txq_count);
358 
359 	sw_index = sa->txq_count;
360 	while (--sw_index >= (int)nb_tx_queues) {
361 		if (sa->txq_info[sw_index].txq != NULL)
362 			sfc_tx_qfini(sa, sw_index);
363 	}
364 
365 	sa->txq_count = nb_tx_queues;
366 }
367 
368 int
369 sfc_tx_configure(struct sfc_adapter *sa)
370 {
371 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
372 	const struct rte_eth_conf *dev_conf = &sa->eth_dev->data->dev_conf;
373 	const unsigned int nb_tx_queues = sa->eth_dev->data->nb_tx_queues;
374 	int rc = 0;
375 
376 	sfc_log_init(sa, "nb_tx_queues=%u (old %u)",
377 		     nb_tx_queues, sa->txq_count);
378 
379 	/*
380 	 * The datapath implementation assumes absence of boundary
381 	 * limits on Tx DMA descriptors. Addition of these checks on
382 	 * datapath would simply make the datapath slower.
383 	 */
384 	if (encp->enc_tx_dma_desc_boundary != 0) {
385 		rc = ENOTSUP;
386 		goto fail_tx_dma_desc_boundary;
387 	}
388 
389 	rc = sfc_tx_check_mode(sa, &dev_conf->txmode);
390 	if (rc != 0)
391 		goto fail_check_mode;
392 
393 	if (nb_tx_queues == sa->txq_count)
394 		goto done;
395 
396 	if (sa->txq_info == NULL) {
397 		sa->txq_info = rte_calloc_socket("sfc-txqs", nb_tx_queues,
398 						 sizeof(sa->txq_info[0]), 0,
399 						 sa->socket_id);
400 		if (sa->txq_info == NULL)
401 			goto fail_txqs_alloc;
402 	} else {
403 		struct sfc_txq_info *new_txq_info;
404 
405 		if (nb_tx_queues < sa->txq_count)
406 			sfc_tx_fini_queues(sa, nb_tx_queues);
407 
408 		new_txq_info =
409 			rte_realloc(sa->txq_info,
410 				    nb_tx_queues * sizeof(sa->txq_info[0]), 0);
411 		if (new_txq_info == NULL && nb_tx_queues > 0)
412 			goto fail_txqs_realloc;
413 
414 		sa->txq_info = new_txq_info;
415 		if (nb_tx_queues > sa->txq_count)
416 			memset(&sa->txq_info[sa->txq_count], 0,
417 			       (nb_tx_queues - sa->txq_count) *
418 			       sizeof(sa->txq_info[0]));
419 	}
420 
421 	while (sa->txq_count < nb_tx_queues) {
422 		rc = sfc_tx_qinit_info(sa, sa->txq_count);
423 		if (rc != 0)
424 			goto fail_tx_qinit_info;
425 
426 		sa->txq_count++;
427 	}
428 
429 done:
430 	return 0;
431 
432 fail_tx_qinit_info:
433 fail_txqs_realloc:
434 fail_txqs_alloc:
435 	sfc_tx_close(sa);
436 
437 fail_check_mode:
438 fail_tx_dma_desc_boundary:
439 	sfc_log_init(sa, "failed (rc = %d)", rc);
440 	return rc;
441 }
442 
443 void
444 sfc_tx_close(struct sfc_adapter *sa)
445 {
446 	sfc_tx_fini_queues(sa, 0);
447 
448 	rte_free(sa->txq_info);
449 	sa->txq_info = NULL;
450 }
451 
452 int
453 sfc_tx_qstart(struct sfc_adapter *sa, unsigned int sw_index)
454 {
455 	uint64_t offloads_supported = sfc_tx_get_dev_offload_caps(sa) |
456 				      sfc_tx_get_queue_offload_caps(sa);
457 	struct rte_eth_dev_data *dev_data;
458 	struct sfc_txq_info *txq_info;
459 	struct sfc_txq *txq;
460 	struct sfc_evq *evq;
461 	uint16_t flags = 0;
462 	unsigned int desc_index;
463 	int rc = 0;
464 
465 	sfc_log_init(sa, "TxQ = %u", sw_index);
466 
467 	SFC_ASSERT(sw_index < sa->txq_count);
468 	txq_info = &sa->txq_info[sw_index];
469 
470 	txq = txq_info->txq;
471 
472 	SFC_ASSERT(txq->state == SFC_TXQ_INITIALIZED);
473 
474 	evq = txq->evq;
475 
476 	rc = sfc_ev_qstart(evq, sfc_evq_index_by_txq_sw_index(sa, sw_index));
477 	if (rc != 0)
478 		goto fail_ev_qstart;
479 
480 	/*
481 	 * The absence of ETH_TXQ_FLAGS_IGNORE is associated with a legacy
482 	 * application which expects that IPv4 checksum offload is enabled
483 	 * all the time as there is no legacy flag to turn off the offload.
484 	 */
485 	if ((txq->offloads & DEV_TX_OFFLOAD_IPV4_CKSUM) ||
486 	    (~txq->flags & ETH_TXQ_FLAGS_IGNORE))
487 		flags |= EFX_TXQ_CKSUM_IPV4;
488 
489 	if ((txq->offloads & DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM) ||
490 	    ((~txq->flags & ETH_TXQ_FLAGS_IGNORE) &&
491 	     (offloads_supported & DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM)))
492 		flags |= EFX_TXQ_CKSUM_INNER_IPV4;
493 
494 	if ((txq->offloads & DEV_TX_OFFLOAD_TCP_CKSUM) ||
495 	    (txq->offloads & DEV_TX_OFFLOAD_UDP_CKSUM)) {
496 		flags |= EFX_TXQ_CKSUM_TCPUDP;
497 
498 		if ((~txq->flags & ETH_TXQ_FLAGS_IGNORE) &&
499 		    (offloads_supported & DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM))
500 			flags |= EFX_TXQ_CKSUM_INNER_TCPUDP;
501 	}
502 
503 	/*
504 	 * The absence of ETH_TXQ_FLAGS_IGNORE is associated with a legacy
505 	 * application. In turn, the absence of ETH_TXQ_FLAGS_NOXSUMTCP is
506 	 * associated specifically with a legacy application which expects
507 	 * both TCP checksum offload and TSO to be enabled because the legacy
508 	 * API does not provide a dedicated mechanism to control TSO.
509 	 */
510 	if ((txq->offloads & DEV_TX_OFFLOAD_TCP_TSO) ||
511 	    ((~txq->flags & ETH_TXQ_FLAGS_IGNORE) &&
512 	     (~txq->flags & ETH_TXQ_FLAGS_NOXSUMTCP)))
513 		flags |= EFX_TXQ_FATSOV2;
514 
515 	rc = efx_tx_qcreate(sa->nic, sw_index, 0, &txq->mem,
516 			    txq_info->entries, 0 /* not used on EF10 */,
517 			    flags, evq->common,
518 			    &txq->common, &desc_index);
519 	if (rc != 0) {
520 		if (sa->tso && (rc == ENOSPC))
521 			sfc_err(sa, "ran out of TSO contexts");
522 
523 		goto fail_tx_qcreate;
524 	}
525 
526 	efx_tx_qenable(txq->common);
527 
528 	txq->state |= SFC_TXQ_STARTED;
529 
530 	rc = sa->dp_tx->qstart(txq->dp, evq->read_ptr, desc_index);
531 	if (rc != 0)
532 		goto fail_dp_qstart;
533 
534 	/*
535 	 * It seems to be used by DPDK for debug purposes only ('rte_ether')
536 	 */
537 	dev_data = sa->eth_dev->data;
538 	dev_data->tx_queue_state[sw_index] = RTE_ETH_QUEUE_STATE_STARTED;
539 
540 	return 0;
541 
542 fail_dp_qstart:
543 	txq->state = SFC_TXQ_INITIALIZED;
544 	efx_tx_qdestroy(txq->common);
545 
546 fail_tx_qcreate:
547 	sfc_ev_qstop(evq);
548 
549 fail_ev_qstart:
550 	return rc;
551 }
552 
553 void
554 sfc_tx_qstop(struct sfc_adapter *sa, unsigned int sw_index)
555 {
556 	struct rte_eth_dev_data *dev_data;
557 	struct sfc_txq_info *txq_info;
558 	struct sfc_txq *txq;
559 	unsigned int retry_count;
560 	unsigned int wait_count;
561 	int rc;
562 
563 	sfc_log_init(sa, "TxQ = %u", sw_index);
564 
565 	SFC_ASSERT(sw_index < sa->txq_count);
566 	txq_info = &sa->txq_info[sw_index];
567 
568 	txq = txq_info->txq;
569 
570 	if (txq->state == SFC_TXQ_INITIALIZED)
571 		return;
572 
573 	SFC_ASSERT(txq->state & SFC_TXQ_STARTED);
574 
575 	sa->dp_tx->qstop(txq->dp, &txq->evq->read_ptr);
576 
577 	/*
578 	 * Retry TX queue flushing in case of flush failed or
579 	 * timeout; in the worst case it can delay for 6 seconds
580 	 */
581 	for (retry_count = 0;
582 	     ((txq->state & SFC_TXQ_FLUSHED) == 0) &&
583 	     (retry_count < SFC_TX_QFLUSH_ATTEMPTS);
584 	     ++retry_count) {
585 		rc = efx_tx_qflush(txq->common);
586 		if (rc != 0) {
587 			txq->state |= (rc == EALREADY) ?
588 				SFC_TXQ_FLUSHED : SFC_TXQ_FLUSH_FAILED;
589 			break;
590 		}
591 
592 		/*
593 		 * Wait for TX queue flush done or flush failed event at least
594 		 * SFC_TX_QFLUSH_POLL_WAIT_MS milliseconds and not more
595 		 * than 2 seconds (SFC_TX_QFLUSH_POLL_WAIT_MS multiplied
596 		 * by SFC_TX_QFLUSH_POLL_ATTEMPTS)
597 		 */
598 		wait_count = 0;
599 		do {
600 			rte_delay_ms(SFC_TX_QFLUSH_POLL_WAIT_MS);
601 			sfc_ev_qpoll(txq->evq);
602 		} while ((txq->state & SFC_TXQ_FLUSHING) &&
603 			 wait_count++ < SFC_TX_QFLUSH_POLL_ATTEMPTS);
604 
605 		if (txq->state & SFC_TXQ_FLUSHING)
606 			sfc_err(sa, "TxQ %u flush timed out", sw_index);
607 
608 		if (txq->state & SFC_TXQ_FLUSHED)
609 			sfc_info(sa, "TxQ %u flushed", sw_index);
610 	}
611 
612 	sa->dp_tx->qreap(txq->dp);
613 
614 	txq->state = SFC_TXQ_INITIALIZED;
615 
616 	efx_tx_qdestroy(txq->common);
617 
618 	sfc_ev_qstop(txq->evq);
619 
620 	/*
621 	 * It seems to be used by DPDK for debug purposes only ('rte_ether')
622 	 */
623 	dev_data = sa->eth_dev->data;
624 	dev_data->tx_queue_state[sw_index] = RTE_ETH_QUEUE_STATE_STOPPED;
625 }
626 
627 int
628 sfc_tx_start(struct sfc_adapter *sa)
629 {
630 	unsigned int sw_index;
631 	int rc = 0;
632 
633 	sfc_log_init(sa, "txq_count = %u", sa->txq_count);
634 
635 	if (sa->tso) {
636 		if (!efx_nic_cfg_get(sa->nic)->enc_fw_assisted_tso_v2_enabled) {
637 			sfc_warn(sa, "TSO support was unable to be restored");
638 			sa->tso = B_FALSE;
639 		}
640 	}
641 
642 	rc = efx_tx_init(sa->nic);
643 	if (rc != 0)
644 		goto fail_efx_tx_init;
645 
646 	for (sw_index = 0; sw_index < sa->txq_count; ++sw_index) {
647 		if (!(sa->txq_info[sw_index].deferred_start) ||
648 		    sa->txq_info[sw_index].deferred_started) {
649 			rc = sfc_tx_qstart(sa, sw_index);
650 			if (rc != 0)
651 				goto fail_tx_qstart;
652 		}
653 	}
654 
655 	return 0;
656 
657 fail_tx_qstart:
658 	while (sw_index-- > 0)
659 		sfc_tx_qstop(sa, sw_index);
660 
661 	efx_tx_fini(sa->nic);
662 
663 fail_efx_tx_init:
664 	sfc_log_init(sa, "failed (rc = %d)", rc);
665 	return rc;
666 }
667 
668 void
669 sfc_tx_stop(struct sfc_adapter *sa)
670 {
671 	unsigned int sw_index;
672 
673 	sfc_log_init(sa, "txq_count = %u", sa->txq_count);
674 
675 	sw_index = sa->txq_count;
676 	while (sw_index-- > 0) {
677 		if (sa->txq_info[sw_index].txq != NULL)
678 			sfc_tx_qstop(sa, sw_index);
679 	}
680 
681 	efx_tx_fini(sa->nic);
682 }
683 
684 static void
685 sfc_efx_tx_reap(struct sfc_efx_txq *txq)
686 {
687 	unsigned int completed;
688 
689 	sfc_ev_qpoll(txq->evq);
690 
691 	for (completed = txq->completed;
692 	     completed != txq->pending; completed++) {
693 		struct sfc_efx_tx_sw_desc *txd;
694 
695 		txd = &txq->sw_ring[completed & txq->ptr_mask];
696 
697 		if (txd->mbuf != NULL) {
698 			rte_pktmbuf_free(txd->mbuf);
699 			txd->mbuf = NULL;
700 		}
701 	}
702 
703 	txq->completed = completed;
704 }
705 
706 /*
707  * The function is used to insert or update VLAN tag;
708  * the firmware has state of the firmware tag to insert per TxQ
709  * (controlled by option descriptors), hence, if the tag of the
710  * packet to be sent is different from one remembered by the firmware,
711  * the function will update it
712  */
713 static unsigned int
714 sfc_efx_tx_maybe_insert_tag(struct sfc_efx_txq *txq, struct rte_mbuf *m,
715 			    efx_desc_t **pend)
716 {
717 	uint16_t this_tag = ((m->ol_flags & PKT_TX_VLAN_PKT) ?
718 			     m->vlan_tci : 0);
719 
720 	if (this_tag == txq->hw_vlan_tci)
721 		return 0;
722 
723 	/*
724 	 * The expression inside SFC_ASSERT() is not desired to be checked in
725 	 * a non-debug build because it might be too expensive on the data path
726 	 */
727 	SFC_ASSERT(efx_nic_cfg_get(txq->evq->sa->nic)->enc_hw_tx_insert_vlan_enabled);
728 
729 	efx_tx_qdesc_vlantci_create(txq->common, rte_cpu_to_be_16(this_tag),
730 				    *pend);
731 	(*pend)++;
732 	txq->hw_vlan_tci = this_tag;
733 
734 	return 1;
735 }
736 
737 static uint16_t
738 sfc_efx_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
739 {
740 	struct sfc_dp_txq *dp_txq = (struct sfc_dp_txq *)tx_queue;
741 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
742 	unsigned int added = txq->added;
743 	unsigned int pushed = added;
744 	unsigned int pkts_sent = 0;
745 	efx_desc_t *pend = &txq->pend_desc[0];
746 	const unsigned int hard_max_fill = txq->max_fill_level;
747 	const unsigned int soft_max_fill = hard_max_fill - txq->free_thresh;
748 	unsigned int fill_level = added - txq->completed;
749 	boolean_t reap_done;
750 	int rc __rte_unused;
751 	struct rte_mbuf **pktp;
752 
753 	if (unlikely((txq->flags & SFC_EFX_TXQ_FLAG_RUNNING) == 0))
754 		goto done;
755 
756 	/*
757 	 * If insufficient space for a single packet is present,
758 	 * we should reap; otherwise, we shouldn't do that all the time
759 	 * to avoid latency increase
760 	 */
761 	reap_done = (fill_level > soft_max_fill);
762 
763 	if (reap_done) {
764 		sfc_efx_tx_reap(txq);
765 		/*
766 		 * Recalculate fill level since 'txq->completed'
767 		 * might have changed on reap
768 		 */
769 		fill_level = added - txq->completed;
770 	}
771 
772 	for (pkts_sent = 0, pktp = &tx_pkts[0];
773 	     (pkts_sent < nb_pkts) && (fill_level <= soft_max_fill);
774 	     pkts_sent++, pktp++) {
775 		struct rte_mbuf		*m_seg = *pktp;
776 		size_t			pkt_len = m_seg->pkt_len;
777 		unsigned int		pkt_descs = 0;
778 		size_t			in_off = 0;
779 
780 		/*
781 		 * Here VLAN TCI is expected to be zero in case if no
782 		 * DEV_TX_OFFLOAD_VLAN_INSERT capability is advertised;
783 		 * if the calling app ignores the absence of
784 		 * DEV_TX_OFFLOAD_VLAN_INSERT and pushes VLAN TCI, then
785 		 * TX_ERROR will occur
786 		 */
787 		pkt_descs += sfc_efx_tx_maybe_insert_tag(txq, m_seg, &pend);
788 
789 		if (m_seg->ol_flags & PKT_TX_TCP_SEG) {
790 			/*
791 			 * We expect correct 'pkt->l[2, 3, 4]_len' values
792 			 * to be set correctly by the caller
793 			 */
794 			if (sfc_efx_tso_do(txq, added, &m_seg, &in_off, &pend,
795 					   &pkt_descs, &pkt_len) != 0) {
796 				/* We may have reached this place for
797 				 * one of the following reasons:
798 				 *
799 				 * 1) Packet header length is greater
800 				 *    than SFC_TSOH_STD_LEN
801 				 * 2) TCP header starts at more then
802 				 *    208 bytes into the frame
803 				 *
804 				 * We will deceive RTE saying that we have sent
805 				 * the packet, but we will actually drop it.
806 				 * Hence, we should revert 'pend' to the
807 				 * previous state (in case we have added
808 				 * VLAN descriptor) and start processing
809 				 * another one packet. But the original
810 				 * mbuf shouldn't be orphaned
811 				 */
812 				pend -= pkt_descs;
813 
814 				rte_pktmbuf_free(*pktp);
815 
816 				continue;
817 			}
818 
819 			/*
820 			 * We've only added 2 FATSOv2 option descriptors
821 			 * and 1 descriptor for the linearized packet header.
822 			 * The outstanding work will be done in the same manner
823 			 * as for the usual non-TSO path
824 			 */
825 		}
826 
827 		for (; m_seg != NULL; m_seg = m_seg->next) {
828 			efsys_dma_addr_t	next_frag;
829 			size_t			seg_len;
830 
831 			seg_len = m_seg->data_len;
832 			next_frag = rte_mbuf_data_iova(m_seg);
833 
834 			/*
835 			 * If we've started TSO transaction few steps earlier,
836 			 * we'll skip packet header using an offset in the
837 			 * current segment (which has been set to the
838 			 * first one containing payload)
839 			 */
840 			seg_len -= in_off;
841 			next_frag += in_off;
842 			in_off = 0;
843 
844 			do {
845 				efsys_dma_addr_t	frag_addr = next_frag;
846 				size_t			frag_len;
847 
848 				/*
849 				 * It is assumed here that there is no
850 				 * limitation on address boundary
851 				 * crossing by DMA descriptor.
852 				 */
853 				frag_len = MIN(seg_len, txq->dma_desc_size_max);
854 				next_frag += frag_len;
855 				seg_len -= frag_len;
856 				pkt_len -= frag_len;
857 
858 				efx_tx_qdesc_dma_create(txq->common,
859 							frag_addr, frag_len,
860 							(pkt_len == 0),
861 							pend++);
862 
863 				pkt_descs++;
864 			} while (seg_len != 0);
865 		}
866 
867 		added += pkt_descs;
868 
869 		fill_level += pkt_descs;
870 		if (unlikely(fill_level > hard_max_fill)) {
871 			/*
872 			 * Our estimation for maximum number of descriptors
873 			 * required to send a packet seems to be wrong.
874 			 * Try to reap (if we haven't yet).
875 			 */
876 			if (!reap_done) {
877 				sfc_efx_tx_reap(txq);
878 				reap_done = B_TRUE;
879 				fill_level = added - txq->completed;
880 				if (fill_level > hard_max_fill) {
881 					pend -= pkt_descs;
882 					break;
883 				}
884 			} else {
885 				pend -= pkt_descs;
886 				break;
887 			}
888 		}
889 
890 		/* Assign mbuf to the last used desc */
891 		txq->sw_ring[(added - 1) & txq->ptr_mask].mbuf = *pktp;
892 	}
893 
894 	if (likely(pkts_sent > 0)) {
895 		rc = efx_tx_qdesc_post(txq->common, txq->pend_desc,
896 				       pend - &txq->pend_desc[0],
897 				       txq->completed, &txq->added);
898 		SFC_ASSERT(rc == 0);
899 
900 		if (likely(pushed != txq->added))
901 			efx_tx_qpush(txq->common, txq->added, pushed);
902 	}
903 
904 #if SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE
905 	if (!reap_done)
906 		sfc_efx_tx_reap(txq);
907 #endif
908 
909 done:
910 	return pkts_sent;
911 }
912 
913 struct sfc_txq *
914 sfc_txq_by_dp_txq(const struct sfc_dp_txq *dp_txq)
915 {
916 	const struct sfc_dp_queue *dpq = &dp_txq->dpq;
917 	struct rte_eth_dev *eth_dev;
918 	struct sfc_adapter *sa;
919 	struct sfc_txq *txq;
920 
921 	SFC_ASSERT(rte_eth_dev_is_valid_port(dpq->port_id));
922 	eth_dev = &rte_eth_devices[dpq->port_id];
923 
924 	sa = eth_dev->data->dev_private;
925 
926 	SFC_ASSERT(dpq->queue_id < sa->txq_count);
927 	txq = sa->txq_info[dpq->queue_id].txq;
928 
929 	SFC_ASSERT(txq != NULL);
930 	return txq;
931 }
932 
933 static sfc_dp_tx_qsize_up_rings_t sfc_efx_tx_qsize_up_rings;
934 static int
935 sfc_efx_tx_qsize_up_rings(uint16_t nb_tx_desc,
936 			  unsigned int *txq_entries,
937 			  unsigned int *evq_entries,
938 			  unsigned int *txq_max_fill_level)
939 {
940 	*txq_entries = nb_tx_desc;
941 	*evq_entries = nb_tx_desc;
942 	*txq_max_fill_level = EFX_TXQ_LIMIT(*txq_entries);
943 	return 0;
944 }
945 
946 static sfc_dp_tx_qcreate_t sfc_efx_tx_qcreate;
947 static int
948 sfc_efx_tx_qcreate(uint16_t port_id, uint16_t queue_id,
949 		   const struct rte_pci_addr *pci_addr,
950 		   int socket_id,
951 		   const struct sfc_dp_tx_qcreate_info *info,
952 		   struct sfc_dp_txq **dp_txqp)
953 {
954 	struct sfc_efx_txq *txq;
955 	struct sfc_txq *ctrl_txq;
956 	int rc;
957 
958 	rc = ENOMEM;
959 	txq = rte_zmalloc_socket("sfc-efx-txq", sizeof(*txq),
960 				 RTE_CACHE_LINE_SIZE, socket_id);
961 	if (txq == NULL)
962 		goto fail_txq_alloc;
963 
964 	sfc_dp_queue_init(&txq->dp.dpq, port_id, queue_id, pci_addr);
965 
966 	rc = ENOMEM;
967 	txq->pend_desc = rte_calloc_socket("sfc-efx-txq-pend-desc",
968 					   EFX_TXQ_LIMIT(info->txq_entries),
969 					   sizeof(*txq->pend_desc), 0,
970 					   socket_id);
971 	if (txq->pend_desc == NULL)
972 		goto fail_pend_desc_alloc;
973 
974 	rc = ENOMEM;
975 	txq->sw_ring = rte_calloc_socket("sfc-efx-txq-sw_ring",
976 					 info->txq_entries,
977 					 sizeof(*txq->sw_ring),
978 					 RTE_CACHE_LINE_SIZE, socket_id);
979 	if (txq->sw_ring == NULL)
980 		goto fail_sw_ring_alloc;
981 
982 	ctrl_txq = sfc_txq_by_dp_txq(&txq->dp);
983 	if (ctrl_txq->evq->sa->tso) {
984 		rc = sfc_efx_tso_alloc_tsoh_objs(txq->sw_ring,
985 						 info->txq_entries, socket_id);
986 		if (rc != 0)
987 			goto fail_alloc_tsoh_objs;
988 	}
989 
990 	txq->evq = ctrl_txq->evq;
991 	txq->ptr_mask = info->txq_entries - 1;
992 	txq->max_fill_level = info->max_fill_level;
993 	txq->free_thresh = info->free_thresh;
994 	txq->dma_desc_size_max = info->dma_desc_size_max;
995 
996 	*dp_txqp = &txq->dp;
997 	return 0;
998 
999 fail_alloc_tsoh_objs:
1000 	rte_free(txq->sw_ring);
1001 
1002 fail_sw_ring_alloc:
1003 	rte_free(txq->pend_desc);
1004 
1005 fail_pend_desc_alloc:
1006 	rte_free(txq);
1007 
1008 fail_txq_alloc:
1009 	return rc;
1010 }
1011 
1012 static sfc_dp_tx_qdestroy_t sfc_efx_tx_qdestroy;
1013 static void
1014 sfc_efx_tx_qdestroy(struct sfc_dp_txq *dp_txq)
1015 {
1016 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1017 
1018 	sfc_efx_tso_free_tsoh_objs(txq->sw_ring, txq->ptr_mask + 1);
1019 	rte_free(txq->sw_ring);
1020 	rte_free(txq->pend_desc);
1021 	rte_free(txq);
1022 }
1023 
1024 static sfc_dp_tx_qstart_t sfc_efx_tx_qstart;
1025 static int
1026 sfc_efx_tx_qstart(struct sfc_dp_txq *dp_txq,
1027 		  __rte_unused unsigned int evq_read_ptr,
1028 		  unsigned int txq_desc_index)
1029 {
1030 	/* libefx-based datapath is specific to libefx-based PMD */
1031 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1032 	struct sfc_txq *ctrl_txq = sfc_txq_by_dp_txq(dp_txq);
1033 
1034 	txq->common = ctrl_txq->common;
1035 
1036 	txq->pending = txq->completed = txq->added = txq_desc_index;
1037 	txq->hw_vlan_tci = 0;
1038 
1039 	txq->flags |= (SFC_EFX_TXQ_FLAG_STARTED | SFC_EFX_TXQ_FLAG_RUNNING);
1040 
1041 	return 0;
1042 }
1043 
1044 static sfc_dp_tx_qstop_t sfc_efx_tx_qstop;
1045 static void
1046 sfc_efx_tx_qstop(struct sfc_dp_txq *dp_txq,
1047 		 __rte_unused unsigned int *evq_read_ptr)
1048 {
1049 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1050 
1051 	txq->flags &= ~SFC_EFX_TXQ_FLAG_RUNNING;
1052 }
1053 
1054 static sfc_dp_tx_qreap_t sfc_efx_tx_qreap;
1055 static void
1056 sfc_efx_tx_qreap(struct sfc_dp_txq *dp_txq)
1057 {
1058 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1059 	unsigned int txds;
1060 
1061 	sfc_efx_tx_reap(txq);
1062 
1063 	for (txds = 0; txds <= txq->ptr_mask; txds++) {
1064 		if (txq->sw_ring[txds].mbuf != NULL) {
1065 			rte_pktmbuf_free(txq->sw_ring[txds].mbuf);
1066 			txq->sw_ring[txds].mbuf = NULL;
1067 		}
1068 	}
1069 
1070 	txq->flags &= ~SFC_EFX_TXQ_FLAG_STARTED;
1071 }
1072 
1073 static sfc_dp_tx_qdesc_status_t sfc_efx_tx_qdesc_status;
1074 static int
1075 sfc_efx_tx_qdesc_status(struct sfc_dp_txq *dp_txq, uint16_t offset)
1076 {
1077 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1078 
1079 	if (unlikely(offset > txq->ptr_mask))
1080 		return -EINVAL;
1081 
1082 	if (unlikely(offset >= txq->max_fill_level))
1083 		return RTE_ETH_TX_DESC_UNAVAIL;
1084 
1085 	/*
1086 	 * Poll EvQ to derive up-to-date 'txq->pending' figure;
1087 	 * it is required for the queue to be running, but the
1088 	 * check is omitted because API design assumes that it
1089 	 * is the duty of the caller to satisfy all conditions
1090 	 */
1091 	SFC_ASSERT((txq->flags & SFC_EFX_TXQ_FLAG_RUNNING) ==
1092 		   SFC_EFX_TXQ_FLAG_RUNNING);
1093 	sfc_ev_qpoll(txq->evq);
1094 
1095 	/*
1096 	 * Ring tail is 'txq->pending', and although descriptors
1097 	 * between 'txq->completed' and 'txq->pending' are still
1098 	 * in use by the driver, they should be reported as DONE
1099 	 */
1100 	if (unlikely(offset < (txq->added - txq->pending)))
1101 		return RTE_ETH_TX_DESC_FULL;
1102 
1103 	/*
1104 	 * There is no separate return value for unused descriptors;
1105 	 * the latter will be reported as DONE because genuine DONE
1106 	 * descriptors will be freed anyway in SW on the next burst
1107 	 */
1108 	return RTE_ETH_TX_DESC_DONE;
1109 }
1110 
1111 struct sfc_dp_tx sfc_efx_tx = {
1112 	.dp = {
1113 		.name		= SFC_KVARG_DATAPATH_EFX,
1114 		.type		= SFC_DP_TX,
1115 		.hw_fw_caps	= 0,
1116 	},
1117 	.features		= SFC_DP_TX_FEAT_VLAN_INSERT |
1118 				  SFC_DP_TX_FEAT_TSO |
1119 				  SFC_DP_TX_FEAT_MULTI_POOL |
1120 				  SFC_DP_TX_FEAT_REFCNT |
1121 				  SFC_DP_TX_FEAT_MULTI_SEG,
1122 	.qsize_up_rings		= sfc_efx_tx_qsize_up_rings,
1123 	.qcreate		= sfc_efx_tx_qcreate,
1124 	.qdestroy		= sfc_efx_tx_qdestroy,
1125 	.qstart			= sfc_efx_tx_qstart,
1126 	.qstop			= sfc_efx_tx_qstop,
1127 	.qreap			= sfc_efx_tx_qreap,
1128 	.qdesc_status		= sfc_efx_tx_qdesc_status,
1129 	.pkt_burst		= sfc_efx_xmit_pkts,
1130 };
1131