xref: /dpdk/drivers/net/sfc/sfc_tx.c (revision 2a7bb4fdf61e9edfb7adbaecb50e728b82da9e23)
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 int
77 sfc_tx_qcheck_conf(struct sfc_adapter *sa, unsigned int txq_max_fill_level,
78 		   const struct rte_eth_txconf *tx_conf,
79 		   uint64_t offloads)
80 {
81 	int rc = 0;
82 
83 	if (tx_conf->tx_rs_thresh != 0) {
84 		sfc_err(sa, "RS bit in transmit descriptor is not supported");
85 		rc = EINVAL;
86 	}
87 
88 	if (tx_conf->tx_free_thresh > txq_max_fill_level) {
89 		sfc_err(sa,
90 			"TxQ free threshold too large: %u vs maximum %u",
91 			tx_conf->tx_free_thresh, txq_max_fill_level);
92 		rc = EINVAL;
93 	}
94 
95 	if (tx_conf->tx_thresh.pthresh != 0 ||
96 	    tx_conf->tx_thresh.hthresh != 0 ||
97 	    tx_conf->tx_thresh.wthresh != 0) {
98 		sfc_warn(sa,
99 			"prefetch/host/writeback thresholds are not supported");
100 	}
101 
102 	/* We either perform both TCP and UDP offload, or no offload at all */
103 	if (((offloads & DEV_TX_OFFLOAD_TCP_CKSUM) == 0) !=
104 	    ((offloads & DEV_TX_OFFLOAD_UDP_CKSUM) == 0)) {
105 		sfc_err(sa, "TCP and UDP offloads can't be set independently");
106 		rc = EINVAL;
107 	}
108 
109 	return rc;
110 }
111 
112 void
113 sfc_tx_qflush_done(struct sfc_txq *txq)
114 {
115 	txq->state |= SFC_TXQ_FLUSHED;
116 	txq->state &= ~SFC_TXQ_FLUSHING;
117 }
118 
119 int
120 sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
121 	     uint16_t nb_tx_desc, unsigned int socket_id,
122 	     const struct rte_eth_txconf *tx_conf)
123 {
124 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
125 	unsigned int txq_entries;
126 	unsigned int evq_entries;
127 	unsigned int txq_max_fill_level;
128 	struct sfc_txq_info *txq_info;
129 	struct sfc_evq *evq;
130 	struct sfc_txq *txq;
131 	int rc = 0;
132 	struct sfc_dp_tx_qcreate_info info;
133 	uint64_t offloads;
134 
135 	sfc_log_init(sa, "TxQ = %u", sw_index);
136 
137 	rc = sa->dp_tx->qsize_up_rings(nb_tx_desc, &txq_entries, &evq_entries,
138 				       &txq_max_fill_level);
139 	if (rc != 0)
140 		goto fail_size_up_rings;
141 	SFC_ASSERT(txq_entries >= EFX_TXQ_MINNDESCS);
142 	SFC_ASSERT(txq_entries <= sa->txq_max_entries);
143 	SFC_ASSERT(txq_entries >= nb_tx_desc);
144 	SFC_ASSERT(txq_max_fill_level <= nb_tx_desc);
145 
146 	offloads = tx_conf->offloads |
147 		sa->eth_dev->data->dev_conf.txmode.offloads;
148 	rc = sfc_tx_qcheck_conf(sa, txq_max_fill_level, tx_conf, offloads);
149 	if (rc != 0)
150 		goto fail_bad_conf;
151 
152 	SFC_ASSERT(sw_index < sa->txq_count);
153 	txq_info = &sa->txq_info[sw_index];
154 
155 	txq_info->entries = txq_entries;
156 
157 	rc = sfc_ev_qinit(sa, SFC_EVQ_TYPE_TX, sw_index,
158 			  evq_entries, socket_id, &evq);
159 	if (rc != 0)
160 		goto fail_ev_qinit;
161 
162 	rc = ENOMEM;
163 	txq = rte_zmalloc_socket("sfc-txq", sizeof(*txq), 0, socket_id);
164 	if (txq == NULL)
165 		goto fail_txq_alloc;
166 
167 	txq_info->txq = txq;
168 
169 	txq->hw_index = sw_index;
170 	txq->evq = evq;
171 	txq->free_thresh =
172 		(tx_conf->tx_free_thresh) ? tx_conf->tx_free_thresh :
173 		SFC_TX_DEFAULT_FREE_THRESH;
174 	txq->offloads = offloads;
175 
176 	rc = sfc_dma_alloc(sa, "txq", sw_index, EFX_TXQ_SIZE(txq_info->entries),
177 			   socket_id, &txq->mem);
178 	if (rc != 0)
179 		goto fail_dma_alloc;
180 
181 	memset(&info, 0, sizeof(info));
182 	info.max_fill_level = txq_max_fill_level;
183 	info.free_thresh = txq->free_thresh;
184 	info.offloads = offloads;
185 	info.txq_entries = txq_info->entries;
186 	info.dma_desc_size_max = encp->enc_tx_dma_desc_size_max;
187 	info.txq_hw_ring = txq->mem.esm_base;
188 	info.evq_entries = evq_entries;
189 	info.evq_hw_ring = evq->mem.esm_base;
190 	info.hw_index = txq->hw_index;
191 	info.mem_bar = sa->mem_bar.esb_base;
192 	info.vi_window_shift = encp->enc_vi_window_shift;
193 	info.tso_tcp_header_offset_limit =
194 		encp->enc_tx_tso_tcp_header_offset_limit;
195 
196 	rc = sa->dp_tx->qcreate(sa->eth_dev->data->port_id, sw_index,
197 				&RTE_ETH_DEV_TO_PCI(sa->eth_dev)->addr,
198 				socket_id, &info, &txq->dp);
199 	if (rc != 0)
200 		goto fail_dp_tx_qinit;
201 
202 	evq->dp_txq = txq->dp;
203 
204 	txq->state = SFC_TXQ_INITIALIZED;
205 
206 	txq_info->deferred_start = (tx_conf->tx_deferred_start != 0);
207 
208 	return 0;
209 
210 fail_dp_tx_qinit:
211 	sfc_dma_free(sa, &txq->mem);
212 
213 fail_dma_alloc:
214 	txq_info->txq = NULL;
215 	rte_free(txq);
216 
217 fail_txq_alloc:
218 	sfc_ev_qfini(evq);
219 
220 fail_ev_qinit:
221 	txq_info->entries = 0;
222 
223 fail_bad_conf:
224 fail_size_up_rings:
225 	sfc_log_init(sa, "failed (TxQ = %u, rc = %d)", sw_index, rc);
226 	return rc;
227 }
228 
229 void
230 sfc_tx_qfini(struct sfc_adapter *sa, unsigned int sw_index)
231 {
232 	struct sfc_txq_info *txq_info;
233 	struct sfc_txq *txq;
234 
235 	sfc_log_init(sa, "TxQ = %u", sw_index);
236 
237 	SFC_ASSERT(sw_index < sa->txq_count);
238 	sa->eth_dev->data->tx_queues[sw_index] = NULL;
239 
240 	txq_info = &sa->txq_info[sw_index];
241 
242 	txq = txq_info->txq;
243 	SFC_ASSERT(txq != NULL);
244 	SFC_ASSERT(txq->state == SFC_TXQ_INITIALIZED);
245 
246 	sa->dp_tx->qdestroy(txq->dp);
247 	txq->dp = NULL;
248 
249 	txq_info->txq = NULL;
250 	txq_info->entries = 0;
251 
252 	sfc_dma_free(sa, &txq->mem);
253 
254 	sfc_ev_qfini(txq->evq);
255 	txq->evq = NULL;
256 
257 	rte_free(txq);
258 }
259 
260 static int
261 sfc_tx_qinit_info(struct sfc_adapter *sa, unsigned int sw_index)
262 {
263 	sfc_log_init(sa, "TxQ = %u", sw_index);
264 
265 	return 0;
266 }
267 
268 static int
269 sfc_tx_check_mode(struct sfc_adapter *sa, const struct rte_eth_txmode *txmode)
270 {
271 	int rc = 0;
272 
273 	switch (txmode->mq_mode) {
274 	case ETH_MQ_TX_NONE:
275 		break;
276 	default:
277 		sfc_err(sa, "Tx multi-queue mode %u not supported",
278 			txmode->mq_mode);
279 		rc = EINVAL;
280 	}
281 
282 	/*
283 	 * These features are claimed to be i40e-specific,
284 	 * but it does make sense to double-check their absence
285 	 */
286 	if (txmode->hw_vlan_reject_tagged) {
287 		sfc_err(sa, "Rejecting tagged packets not supported");
288 		rc = EINVAL;
289 	}
290 
291 	if (txmode->hw_vlan_reject_untagged) {
292 		sfc_err(sa, "Rejecting untagged packets not supported");
293 		rc = EINVAL;
294 	}
295 
296 	if (txmode->hw_vlan_insert_pvid) {
297 		sfc_err(sa, "Port-based VLAN insertion not supported");
298 		rc = EINVAL;
299 	}
300 
301 	return rc;
302 }
303 
304 /**
305  * Destroy excess queues that are no longer needed after reconfiguration
306  * or complete close.
307  */
308 static void
309 sfc_tx_fini_queues(struct sfc_adapter *sa, unsigned int nb_tx_queues)
310 {
311 	int sw_index;
312 
313 	SFC_ASSERT(nb_tx_queues <= sa->txq_count);
314 
315 	sw_index = sa->txq_count;
316 	while (--sw_index >= (int)nb_tx_queues) {
317 		if (sa->txq_info[sw_index].txq != NULL)
318 			sfc_tx_qfini(sa, sw_index);
319 	}
320 
321 	sa->txq_count = nb_tx_queues;
322 }
323 
324 int
325 sfc_tx_configure(struct sfc_adapter *sa)
326 {
327 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
328 	const struct rte_eth_conf *dev_conf = &sa->eth_dev->data->dev_conf;
329 	const unsigned int nb_tx_queues = sa->eth_dev->data->nb_tx_queues;
330 	int rc = 0;
331 
332 	sfc_log_init(sa, "nb_tx_queues=%u (old %u)",
333 		     nb_tx_queues, sa->txq_count);
334 
335 	/*
336 	 * The datapath implementation assumes absence of boundary
337 	 * limits on Tx DMA descriptors. Addition of these checks on
338 	 * datapath would simply make the datapath slower.
339 	 */
340 	if (encp->enc_tx_dma_desc_boundary != 0) {
341 		rc = ENOTSUP;
342 		goto fail_tx_dma_desc_boundary;
343 	}
344 
345 	rc = sfc_tx_check_mode(sa, &dev_conf->txmode);
346 	if (rc != 0)
347 		goto fail_check_mode;
348 
349 	if (nb_tx_queues == sa->txq_count)
350 		goto done;
351 
352 	if (sa->txq_info == NULL) {
353 		sa->txq_info = rte_calloc_socket("sfc-txqs", nb_tx_queues,
354 						 sizeof(sa->txq_info[0]), 0,
355 						 sa->socket_id);
356 		if (sa->txq_info == NULL)
357 			goto fail_txqs_alloc;
358 	} else {
359 		struct sfc_txq_info *new_txq_info;
360 
361 		if (nb_tx_queues < sa->txq_count)
362 			sfc_tx_fini_queues(sa, nb_tx_queues);
363 
364 		new_txq_info =
365 			rte_realloc(sa->txq_info,
366 				    nb_tx_queues * sizeof(sa->txq_info[0]), 0);
367 		if (new_txq_info == NULL && nb_tx_queues > 0)
368 			goto fail_txqs_realloc;
369 
370 		sa->txq_info = new_txq_info;
371 		if (nb_tx_queues > sa->txq_count)
372 			memset(&sa->txq_info[sa->txq_count], 0,
373 			       (nb_tx_queues - sa->txq_count) *
374 			       sizeof(sa->txq_info[0]));
375 	}
376 
377 	while (sa->txq_count < nb_tx_queues) {
378 		rc = sfc_tx_qinit_info(sa, sa->txq_count);
379 		if (rc != 0)
380 			goto fail_tx_qinit_info;
381 
382 		sa->txq_count++;
383 	}
384 
385 done:
386 	return 0;
387 
388 fail_tx_qinit_info:
389 fail_txqs_realloc:
390 fail_txqs_alloc:
391 	sfc_tx_close(sa);
392 
393 fail_check_mode:
394 fail_tx_dma_desc_boundary:
395 	sfc_log_init(sa, "failed (rc = %d)", rc);
396 	return rc;
397 }
398 
399 void
400 sfc_tx_close(struct sfc_adapter *sa)
401 {
402 	sfc_tx_fini_queues(sa, 0);
403 
404 	rte_free(sa->txq_info);
405 	sa->txq_info = NULL;
406 }
407 
408 int
409 sfc_tx_qstart(struct sfc_adapter *sa, unsigned int sw_index)
410 {
411 	uint64_t offloads_supported = sfc_tx_get_dev_offload_caps(sa) |
412 				      sfc_tx_get_queue_offload_caps(sa);
413 	struct rte_eth_dev_data *dev_data;
414 	struct sfc_txq_info *txq_info;
415 	struct sfc_txq *txq;
416 	struct sfc_evq *evq;
417 	uint16_t flags = 0;
418 	unsigned int desc_index;
419 	int rc = 0;
420 
421 	sfc_log_init(sa, "TxQ = %u", sw_index);
422 
423 	SFC_ASSERT(sw_index < sa->txq_count);
424 	txq_info = &sa->txq_info[sw_index];
425 
426 	txq = txq_info->txq;
427 
428 	SFC_ASSERT(txq != NULL);
429 	SFC_ASSERT(txq->state == SFC_TXQ_INITIALIZED);
430 
431 	evq = txq->evq;
432 
433 	rc = sfc_ev_qstart(evq, sfc_evq_index_by_txq_sw_index(sa, sw_index));
434 	if (rc != 0)
435 		goto fail_ev_qstart;
436 
437 	if (txq->offloads & DEV_TX_OFFLOAD_IPV4_CKSUM)
438 		flags |= EFX_TXQ_CKSUM_IPV4;
439 
440 	if (txq->offloads & DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM)
441 		flags |= EFX_TXQ_CKSUM_INNER_IPV4;
442 
443 	if ((txq->offloads & DEV_TX_OFFLOAD_TCP_CKSUM) ||
444 	    (txq->offloads & DEV_TX_OFFLOAD_UDP_CKSUM)) {
445 		flags |= EFX_TXQ_CKSUM_TCPUDP;
446 
447 		if (offloads_supported & DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM)
448 			flags |= EFX_TXQ_CKSUM_INNER_TCPUDP;
449 	}
450 
451 	if (txq->offloads & DEV_TX_OFFLOAD_TCP_TSO)
452 		flags |= EFX_TXQ_FATSOV2;
453 
454 	rc = efx_tx_qcreate(sa->nic, txq->hw_index, 0, &txq->mem,
455 			    txq_info->entries, 0 /* not used on EF10 */,
456 			    flags, evq->common,
457 			    &txq->common, &desc_index);
458 	if (rc != 0) {
459 		if (sa->tso && (rc == ENOSPC))
460 			sfc_err(sa, "ran out of TSO contexts");
461 
462 		goto fail_tx_qcreate;
463 	}
464 
465 	efx_tx_qenable(txq->common);
466 
467 	txq->state |= SFC_TXQ_STARTED;
468 
469 	rc = sa->dp_tx->qstart(txq->dp, evq->read_ptr, desc_index);
470 	if (rc != 0)
471 		goto fail_dp_qstart;
472 
473 	/*
474 	 * It seems to be used by DPDK for debug purposes only ('rte_ether')
475 	 */
476 	dev_data = sa->eth_dev->data;
477 	dev_data->tx_queue_state[sw_index] = RTE_ETH_QUEUE_STATE_STARTED;
478 
479 	return 0;
480 
481 fail_dp_qstart:
482 	txq->state = SFC_TXQ_INITIALIZED;
483 	efx_tx_qdestroy(txq->common);
484 
485 fail_tx_qcreate:
486 	sfc_ev_qstop(evq);
487 
488 fail_ev_qstart:
489 	return rc;
490 }
491 
492 void
493 sfc_tx_qstop(struct sfc_adapter *sa, unsigned int sw_index)
494 {
495 	struct rte_eth_dev_data *dev_data;
496 	struct sfc_txq_info *txq_info;
497 	struct sfc_txq *txq;
498 	unsigned int retry_count;
499 	unsigned int wait_count;
500 	int rc;
501 
502 	sfc_log_init(sa, "TxQ = %u", sw_index);
503 
504 	SFC_ASSERT(sw_index < sa->txq_count);
505 	txq_info = &sa->txq_info[sw_index];
506 
507 	txq = txq_info->txq;
508 
509 	if (txq == NULL || txq->state == SFC_TXQ_INITIALIZED)
510 		return;
511 
512 	SFC_ASSERT(txq->state & SFC_TXQ_STARTED);
513 
514 	sa->dp_tx->qstop(txq->dp, &txq->evq->read_ptr);
515 
516 	/*
517 	 * Retry TX queue flushing in case of flush failed or
518 	 * timeout; in the worst case it can delay for 6 seconds
519 	 */
520 	for (retry_count = 0;
521 	     ((txq->state & SFC_TXQ_FLUSHED) == 0) &&
522 	     (retry_count < SFC_TX_QFLUSH_ATTEMPTS);
523 	     ++retry_count) {
524 		rc = efx_tx_qflush(txq->common);
525 		if (rc != 0) {
526 			txq->state |= (rc == EALREADY) ?
527 				SFC_TXQ_FLUSHED : SFC_TXQ_FLUSH_FAILED;
528 			break;
529 		}
530 
531 		/*
532 		 * Wait for TX queue flush done or flush failed event at least
533 		 * SFC_TX_QFLUSH_POLL_WAIT_MS milliseconds and not more
534 		 * than 2 seconds (SFC_TX_QFLUSH_POLL_WAIT_MS multiplied
535 		 * by SFC_TX_QFLUSH_POLL_ATTEMPTS)
536 		 */
537 		wait_count = 0;
538 		do {
539 			rte_delay_ms(SFC_TX_QFLUSH_POLL_WAIT_MS);
540 			sfc_ev_qpoll(txq->evq);
541 		} while ((txq->state & SFC_TXQ_FLUSHING) &&
542 			 wait_count++ < SFC_TX_QFLUSH_POLL_ATTEMPTS);
543 
544 		if (txq->state & SFC_TXQ_FLUSHING)
545 			sfc_err(sa, "TxQ %u flush timed out", sw_index);
546 
547 		if (txq->state & SFC_TXQ_FLUSHED)
548 			sfc_notice(sa, "TxQ %u flushed", sw_index);
549 	}
550 
551 	sa->dp_tx->qreap(txq->dp);
552 
553 	txq->state = SFC_TXQ_INITIALIZED;
554 
555 	efx_tx_qdestroy(txq->common);
556 
557 	sfc_ev_qstop(txq->evq);
558 
559 	/*
560 	 * It seems to be used by DPDK for debug purposes only ('rte_ether')
561 	 */
562 	dev_data = sa->eth_dev->data;
563 	dev_data->tx_queue_state[sw_index] = RTE_ETH_QUEUE_STATE_STOPPED;
564 }
565 
566 int
567 sfc_tx_start(struct sfc_adapter *sa)
568 {
569 	unsigned int sw_index;
570 	int rc = 0;
571 
572 	sfc_log_init(sa, "txq_count = %u", sa->txq_count);
573 
574 	if (sa->tso) {
575 		if (!efx_nic_cfg_get(sa->nic)->enc_fw_assisted_tso_v2_enabled) {
576 			sfc_warn(sa, "TSO support was unable to be restored");
577 			sa->tso = B_FALSE;
578 		}
579 	}
580 
581 	rc = efx_tx_init(sa->nic);
582 	if (rc != 0)
583 		goto fail_efx_tx_init;
584 
585 	for (sw_index = 0; sw_index < sa->txq_count; ++sw_index) {
586 		if (sa->txq_info[sw_index].txq != NULL &&
587 		    (!(sa->txq_info[sw_index].deferred_start) ||
588 		     sa->txq_info[sw_index].deferred_started)) {
589 			rc = sfc_tx_qstart(sa, sw_index);
590 			if (rc != 0)
591 				goto fail_tx_qstart;
592 		}
593 	}
594 
595 	return 0;
596 
597 fail_tx_qstart:
598 	while (sw_index-- > 0)
599 		sfc_tx_qstop(sa, sw_index);
600 
601 	efx_tx_fini(sa->nic);
602 
603 fail_efx_tx_init:
604 	sfc_log_init(sa, "failed (rc = %d)", rc);
605 	return rc;
606 }
607 
608 void
609 sfc_tx_stop(struct sfc_adapter *sa)
610 {
611 	unsigned int sw_index;
612 
613 	sfc_log_init(sa, "txq_count = %u", sa->txq_count);
614 
615 	sw_index = sa->txq_count;
616 	while (sw_index-- > 0) {
617 		if (sa->txq_info[sw_index].txq != NULL)
618 			sfc_tx_qstop(sa, sw_index);
619 	}
620 
621 	efx_tx_fini(sa->nic);
622 }
623 
624 static void
625 sfc_efx_tx_reap(struct sfc_efx_txq *txq)
626 {
627 	unsigned int completed;
628 
629 	sfc_ev_qpoll(txq->evq);
630 
631 	for (completed = txq->completed;
632 	     completed != txq->pending; completed++) {
633 		struct sfc_efx_tx_sw_desc *txd;
634 
635 		txd = &txq->sw_ring[completed & txq->ptr_mask];
636 
637 		if (txd->mbuf != NULL) {
638 			rte_pktmbuf_free(txd->mbuf);
639 			txd->mbuf = NULL;
640 		}
641 	}
642 
643 	txq->completed = completed;
644 }
645 
646 /*
647  * The function is used to insert or update VLAN tag;
648  * the firmware has state of the firmware tag to insert per TxQ
649  * (controlled by option descriptors), hence, if the tag of the
650  * packet to be sent is different from one remembered by the firmware,
651  * the function will update it
652  */
653 static unsigned int
654 sfc_efx_tx_maybe_insert_tag(struct sfc_efx_txq *txq, struct rte_mbuf *m,
655 			    efx_desc_t **pend)
656 {
657 	uint16_t this_tag = ((m->ol_flags & PKT_TX_VLAN_PKT) ?
658 			     m->vlan_tci : 0);
659 
660 	if (this_tag == txq->hw_vlan_tci)
661 		return 0;
662 
663 	/*
664 	 * The expression inside SFC_ASSERT() is not desired to be checked in
665 	 * a non-debug build because it might be too expensive on the data path
666 	 */
667 	SFC_ASSERT(efx_nic_cfg_get(txq->evq->sa->nic)->enc_hw_tx_insert_vlan_enabled);
668 
669 	efx_tx_qdesc_vlantci_create(txq->common, rte_cpu_to_be_16(this_tag),
670 				    *pend);
671 	(*pend)++;
672 	txq->hw_vlan_tci = this_tag;
673 
674 	return 1;
675 }
676 
677 static uint16_t
678 sfc_efx_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
679 {
680 	struct sfc_dp_txq *dp_txq = (struct sfc_dp_txq *)tx_queue;
681 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
682 	unsigned int added = txq->added;
683 	unsigned int pushed = added;
684 	unsigned int pkts_sent = 0;
685 	efx_desc_t *pend = &txq->pend_desc[0];
686 	const unsigned int hard_max_fill = txq->max_fill_level;
687 	const unsigned int soft_max_fill = hard_max_fill - txq->free_thresh;
688 	unsigned int fill_level = added - txq->completed;
689 	boolean_t reap_done;
690 	int rc __rte_unused;
691 	struct rte_mbuf **pktp;
692 
693 	if (unlikely((txq->flags & SFC_EFX_TXQ_FLAG_RUNNING) == 0))
694 		goto done;
695 
696 	/*
697 	 * If insufficient space for a single packet is present,
698 	 * we should reap; otherwise, we shouldn't do that all the time
699 	 * to avoid latency increase
700 	 */
701 	reap_done = (fill_level > soft_max_fill);
702 
703 	if (reap_done) {
704 		sfc_efx_tx_reap(txq);
705 		/*
706 		 * Recalculate fill level since 'txq->completed'
707 		 * might have changed on reap
708 		 */
709 		fill_level = added - txq->completed;
710 	}
711 
712 	for (pkts_sent = 0, pktp = &tx_pkts[0];
713 	     (pkts_sent < nb_pkts) && (fill_level <= soft_max_fill);
714 	     pkts_sent++, pktp++) {
715 		uint16_t		hw_vlan_tci_prev = txq->hw_vlan_tci;
716 		struct rte_mbuf		*m_seg = *pktp;
717 		size_t			pkt_len = m_seg->pkt_len;
718 		unsigned int		pkt_descs = 0;
719 		size_t			in_off = 0;
720 
721 		/*
722 		 * Here VLAN TCI is expected to be zero in case if no
723 		 * DEV_TX_OFFLOAD_VLAN_INSERT capability is advertised;
724 		 * if the calling app ignores the absence of
725 		 * DEV_TX_OFFLOAD_VLAN_INSERT and pushes VLAN TCI, then
726 		 * TX_ERROR will occur
727 		 */
728 		pkt_descs += sfc_efx_tx_maybe_insert_tag(txq, m_seg, &pend);
729 
730 		if (m_seg->ol_flags & PKT_TX_TCP_SEG) {
731 			/*
732 			 * We expect correct 'pkt->l[2, 3, 4]_len' values
733 			 * to be set correctly by the caller
734 			 */
735 			if (sfc_efx_tso_do(txq, added, &m_seg, &in_off, &pend,
736 					   &pkt_descs, &pkt_len) != 0) {
737 				/* We may have reached this place for
738 				 * one of the following reasons:
739 				 *
740 				 * 1) Packet header length is greater
741 				 *    than SFC_TSOH_STD_LEN
742 				 * 2) TCP header starts at more then
743 				 *    208 bytes into the frame
744 				 *
745 				 * We will deceive RTE saying that we have sent
746 				 * the packet, but we will actually drop it.
747 				 * Hence, we should revert 'pend' to the
748 				 * previous state (in case we have added
749 				 * VLAN descriptor) and start processing
750 				 * another one packet. But the original
751 				 * mbuf shouldn't be orphaned
752 				 */
753 				pend -= pkt_descs;
754 				txq->hw_vlan_tci = hw_vlan_tci_prev;
755 
756 				rte_pktmbuf_free(*pktp);
757 
758 				continue;
759 			}
760 
761 			/*
762 			 * We've only added 2 FATSOv2 option descriptors
763 			 * and 1 descriptor for the linearized packet header.
764 			 * The outstanding work will be done in the same manner
765 			 * as for the usual non-TSO path
766 			 */
767 		}
768 
769 		for (; m_seg != NULL; m_seg = m_seg->next) {
770 			efsys_dma_addr_t	next_frag;
771 			size_t			seg_len;
772 
773 			seg_len = m_seg->data_len;
774 			next_frag = rte_mbuf_data_iova(m_seg);
775 
776 			/*
777 			 * If we've started TSO transaction few steps earlier,
778 			 * we'll skip packet header using an offset in the
779 			 * current segment (which has been set to the
780 			 * first one containing payload)
781 			 */
782 			seg_len -= in_off;
783 			next_frag += in_off;
784 			in_off = 0;
785 
786 			do {
787 				efsys_dma_addr_t	frag_addr = next_frag;
788 				size_t			frag_len;
789 
790 				/*
791 				 * It is assumed here that there is no
792 				 * limitation on address boundary
793 				 * crossing by DMA descriptor.
794 				 */
795 				frag_len = MIN(seg_len, txq->dma_desc_size_max);
796 				next_frag += frag_len;
797 				seg_len -= frag_len;
798 				pkt_len -= frag_len;
799 
800 				efx_tx_qdesc_dma_create(txq->common,
801 							frag_addr, frag_len,
802 							(pkt_len == 0),
803 							pend++);
804 
805 				pkt_descs++;
806 			} while (seg_len != 0);
807 		}
808 
809 		added += pkt_descs;
810 
811 		fill_level += pkt_descs;
812 		if (unlikely(fill_level > hard_max_fill)) {
813 			/*
814 			 * Our estimation for maximum number of descriptors
815 			 * required to send a packet seems to be wrong.
816 			 * Try to reap (if we haven't yet).
817 			 */
818 			if (!reap_done) {
819 				sfc_efx_tx_reap(txq);
820 				reap_done = B_TRUE;
821 				fill_level = added - txq->completed;
822 				if (fill_level > hard_max_fill) {
823 					pend -= pkt_descs;
824 					txq->hw_vlan_tci = hw_vlan_tci_prev;
825 					break;
826 				}
827 			} else {
828 				pend -= pkt_descs;
829 				txq->hw_vlan_tci = hw_vlan_tci_prev;
830 				break;
831 			}
832 		}
833 
834 		/* Assign mbuf to the last used desc */
835 		txq->sw_ring[(added - 1) & txq->ptr_mask].mbuf = *pktp;
836 	}
837 
838 	if (likely(pkts_sent > 0)) {
839 		rc = efx_tx_qdesc_post(txq->common, txq->pend_desc,
840 				       pend - &txq->pend_desc[0],
841 				       txq->completed, &txq->added);
842 		SFC_ASSERT(rc == 0);
843 
844 		if (likely(pushed != txq->added))
845 			efx_tx_qpush(txq->common, txq->added, pushed);
846 	}
847 
848 #if SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE
849 	if (!reap_done)
850 		sfc_efx_tx_reap(txq);
851 #endif
852 
853 done:
854 	return pkts_sent;
855 }
856 
857 struct sfc_txq *
858 sfc_txq_by_dp_txq(const struct sfc_dp_txq *dp_txq)
859 {
860 	const struct sfc_dp_queue *dpq = &dp_txq->dpq;
861 	struct rte_eth_dev *eth_dev;
862 	struct sfc_adapter *sa;
863 	struct sfc_txq *txq;
864 
865 	SFC_ASSERT(rte_eth_dev_is_valid_port(dpq->port_id));
866 	eth_dev = &rte_eth_devices[dpq->port_id];
867 
868 	sa = eth_dev->data->dev_private;
869 
870 	SFC_ASSERT(dpq->queue_id < sa->txq_count);
871 	txq = sa->txq_info[dpq->queue_id].txq;
872 
873 	SFC_ASSERT(txq != NULL);
874 	return txq;
875 }
876 
877 static sfc_dp_tx_qsize_up_rings_t sfc_efx_tx_qsize_up_rings;
878 static int
879 sfc_efx_tx_qsize_up_rings(uint16_t nb_tx_desc,
880 			  unsigned int *txq_entries,
881 			  unsigned int *evq_entries,
882 			  unsigned int *txq_max_fill_level)
883 {
884 	*txq_entries = nb_tx_desc;
885 	*evq_entries = nb_tx_desc;
886 	*txq_max_fill_level = EFX_TXQ_LIMIT(*txq_entries);
887 	return 0;
888 }
889 
890 static sfc_dp_tx_qcreate_t sfc_efx_tx_qcreate;
891 static int
892 sfc_efx_tx_qcreate(uint16_t port_id, uint16_t queue_id,
893 		   const struct rte_pci_addr *pci_addr,
894 		   int socket_id,
895 		   const struct sfc_dp_tx_qcreate_info *info,
896 		   struct sfc_dp_txq **dp_txqp)
897 {
898 	struct sfc_efx_txq *txq;
899 	struct sfc_txq *ctrl_txq;
900 	int rc;
901 
902 	rc = ENOMEM;
903 	txq = rte_zmalloc_socket("sfc-efx-txq", sizeof(*txq),
904 				 RTE_CACHE_LINE_SIZE, socket_id);
905 	if (txq == NULL)
906 		goto fail_txq_alloc;
907 
908 	sfc_dp_queue_init(&txq->dp.dpq, port_id, queue_id, pci_addr);
909 
910 	rc = ENOMEM;
911 	txq->pend_desc = rte_calloc_socket("sfc-efx-txq-pend-desc",
912 					   EFX_TXQ_LIMIT(info->txq_entries),
913 					   sizeof(*txq->pend_desc), 0,
914 					   socket_id);
915 	if (txq->pend_desc == NULL)
916 		goto fail_pend_desc_alloc;
917 
918 	rc = ENOMEM;
919 	txq->sw_ring = rte_calloc_socket("sfc-efx-txq-sw_ring",
920 					 info->txq_entries,
921 					 sizeof(*txq->sw_ring),
922 					 RTE_CACHE_LINE_SIZE, socket_id);
923 	if (txq->sw_ring == NULL)
924 		goto fail_sw_ring_alloc;
925 
926 	ctrl_txq = sfc_txq_by_dp_txq(&txq->dp);
927 	if (ctrl_txq->evq->sa->tso) {
928 		rc = sfc_efx_tso_alloc_tsoh_objs(txq->sw_ring,
929 						 info->txq_entries, socket_id);
930 		if (rc != 0)
931 			goto fail_alloc_tsoh_objs;
932 	}
933 
934 	txq->evq = ctrl_txq->evq;
935 	txq->ptr_mask = info->txq_entries - 1;
936 	txq->max_fill_level = info->max_fill_level;
937 	txq->free_thresh = info->free_thresh;
938 	txq->dma_desc_size_max = info->dma_desc_size_max;
939 
940 	*dp_txqp = &txq->dp;
941 	return 0;
942 
943 fail_alloc_tsoh_objs:
944 	rte_free(txq->sw_ring);
945 
946 fail_sw_ring_alloc:
947 	rte_free(txq->pend_desc);
948 
949 fail_pend_desc_alloc:
950 	rte_free(txq);
951 
952 fail_txq_alloc:
953 	return rc;
954 }
955 
956 static sfc_dp_tx_qdestroy_t sfc_efx_tx_qdestroy;
957 static void
958 sfc_efx_tx_qdestroy(struct sfc_dp_txq *dp_txq)
959 {
960 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
961 
962 	sfc_efx_tso_free_tsoh_objs(txq->sw_ring, txq->ptr_mask + 1);
963 	rte_free(txq->sw_ring);
964 	rte_free(txq->pend_desc);
965 	rte_free(txq);
966 }
967 
968 static sfc_dp_tx_qstart_t sfc_efx_tx_qstart;
969 static int
970 sfc_efx_tx_qstart(struct sfc_dp_txq *dp_txq,
971 		  __rte_unused unsigned int evq_read_ptr,
972 		  unsigned int txq_desc_index)
973 {
974 	/* libefx-based datapath is specific to libefx-based PMD */
975 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
976 	struct sfc_txq *ctrl_txq = sfc_txq_by_dp_txq(dp_txq);
977 
978 	txq->common = ctrl_txq->common;
979 
980 	txq->pending = txq->completed = txq->added = txq_desc_index;
981 	txq->hw_vlan_tci = 0;
982 
983 	txq->flags |= (SFC_EFX_TXQ_FLAG_STARTED | SFC_EFX_TXQ_FLAG_RUNNING);
984 
985 	return 0;
986 }
987 
988 static sfc_dp_tx_qstop_t sfc_efx_tx_qstop;
989 static void
990 sfc_efx_tx_qstop(struct sfc_dp_txq *dp_txq,
991 		 __rte_unused unsigned int *evq_read_ptr)
992 {
993 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
994 
995 	txq->flags &= ~SFC_EFX_TXQ_FLAG_RUNNING;
996 }
997 
998 static sfc_dp_tx_qreap_t sfc_efx_tx_qreap;
999 static void
1000 sfc_efx_tx_qreap(struct sfc_dp_txq *dp_txq)
1001 {
1002 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1003 	unsigned int txds;
1004 
1005 	sfc_efx_tx_reap(txq);
1006 
1007 	for (txds = 0; txds <= txq->ptr_mask; txds++) {
1008 		if (txq->sw_ring[txds].mbuf != NULL) {
1009 			rte_pktmbuf_free(txq->sw_ring[txds].mbuf);
1010 			txq->sw_ring[txds].mbuf = NULL;
1011 		}
1012 	}
1013 
1014 	txq->flags &= ~SFC_EFX_TXQ_FLAG_STARTED;
1015 }
1016 
1017 static sfc_dp_tx_qdesc_status_t sfc_efx_tx_qdesc_status;
1018 static int
1019 sfc_efx_tx_qdesc_status(struct sfc_dp_txq *dp_txq, uint16_t offset)
1020 {
1021 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1022 
1023 	if (unlikely(offset > txq->ptr_mask))
1024 		return -EINVAL;
1025 
1026 	if (unlikely(offset >= txq->max_fill_level))
1027 		return RTE_ETH_TX_DESC_UNAVAIL;
1028 
1029 	/*
1030 	 * Poll EvQ to derive up-to-date 'txq->pending' figure;
1031 	 * it is required for the queue to be running, but the
1032 	 * check is omitted because API design assumes that it
1033 	 * is the duty of the caller to satisfy all conditions
1034 	 */
1035 	SFC_ASSERT((txq->flags & SFC_EFX_TXQ_FLAG_RUNNING) ==
1036 		   SFC_EFX_TXQ_FLAG_RUNNING);
1037 	sfc_ev_qpoll(txq->evq);
1038 
1039 	/*
1040 	 * Ring tail is 'txq->pending', and although descriptors
1041 	 * between 'txq->completed' and 'txq->pending' are still
1042 	 * in use by the driver, they should be reported as DONE
1043 	 */
1044 	if (unlikely(offset < (txq->added - txq->pending)))
1045 		return RTE_ETH_TX_DESC_FULL;
1046 
1047 	/*
1048 	 * There is no separate return value for unused descriptors;
1049 	 * the latter will be reported as DONE because genuine DONE
1050 	 * descriptors will be freed anyway in SW on the next burst
1051 	 */
1052 	return RTE_ETH_TX_DESC_DONE;
1053 }
1054 
1055 struct sfc_dp_tx sfc_efx_tx = {
1056 	.dp = {
1057 		.name		= SFC_KVARG_DATAPATH_EFX,
1058 		.type		= SFC_DP_TX,
1059 		.hw_fw_caps	= 0,
1060 	},
1061 	.features		= SFC_DP_TX_FEAT_VLAN_INSERT |
1062 				  SFC_DP_TX_FEAT_TSO |
1063 				  SFC_DP_TX_FEAT_MULTI_POOL |
1064 				  SFC_DP_TX_FEAT_REFCNT |
1065 				  SFC_DP_TX_FEAT_MULTI_SEG,
1066 	.qsize_up_rings		= sfc_efx_tx_qsize_up_rings,
1067 	.qcreate		= sfc_efx_tx_qcreate,
1068 	.qdestroy		= sfc_efx_tx_qdestroy,
1069 	.qstart			= sfc_efx_tx_qstart,
1070 	.qstop			= sfc_efx_tx_qstop,
1071 	.qreap			= sfc_efx_tx_qreap,
1072 	.qdesc_status		= sfc_efx_tx_qdesc_status,
1073 	.pkt_burst		= sfc_efx_xmit_pkts,
1074 };
1075