xref: /dpdk/drivers/net/sfc/sfc_tx.c (revision 945acb4a0d644d194f1823084a234f9c286dcf8c)
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 static int
38 sfc_tx_qcheck_conf(struct sfc_adapter *sa, unsigned int txq_max_fill_level,
39 		   const struct rte_eth_txconf *tx_conf)
40 {
41 	unsigned int flags = tx_conf->txq_flags;
42 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
43 	int rc = 0;
44 
45 	if (tx_conf->tx_rs_thresh != 0) {
46 		sfc_err(sa, "RS bit in transmit descriptor is not supported");
47 		rc = EINVAL;
48 	}
49 
50 	if (tx_conf->tx_free_thresh > txq_max_fill_level) {
51 		sfc_err(sa,
52 			"TxQ free threshold too large: %u vs maximum %u",
53 			tx_conf->tx_free_thresh, txq_max_fill_level);
54 		rc = EINVAL;
55 	}
56 
57 	if (tx_conf->tx_thresh.pthresh != 0 ||
58 	    tx_conf->tx_thresh.hthresh != 0 ||
59 	    tx_conf->tx_thresh.wthresh != 0) {
60 		sfc_warn(sa,
61 			"prefetch/host/writeback thresholds are not supported");
62 	}
63 
64 	if (((flags & ETH_TXQ_FLAGS_NOMULTSEGS) == 0) &&
65 	    (~sa->dp_tx->features & SFC_DP_TX_FEAT_MULTI_SEG)) {
66 		sfc_err(sa, "Multi-segment is not supported by %s datapath",
67 			sa->dp_tx->dp.name);
68 		rc = EINVAL;
69 	}
70 
71 	if (((flags & ETH_TXQ_FLAGS_NOMULTMEMP) == 0) &&
72 	    (~sa->dp_tx->features & SFC_DP_TX_FEAT_MULTI_POOL)) {
73 		sfc_err(sa, "multi-mempool is not supported by %s datapath",
74 			sa->dp_tx->dp.name);
75 		rc = EINVAL;
76 	}
77 
78 	if (((flags & ETH_TXQ_FLAGS_NOREFCOUNT) == 0) &&
79 	    (~sa->dp_tx->features & SFC_DP_TX_FEAT_REFCNT)) {
80 		sfc_err(sa,
81 			"mbuf reference counters are neglected by %s datapath",
82 			sa->dp_tx->dp.name);
83 		rc = EINVAL;
84 	}
85 
86 	if ((flags & ETH_TXQ_FLAGS_NOVLANOFFL) == 0) {
87 		if (!encp->enc_hw_tx_insert_vlan_enabled) {
88 			sfc_err(sa, "VLAN offload is not supported");
89 			rc = EINVAL;
90 		} else if (~sa->dp_tx->features & SFC_DP_TX_FEAT_VLAN_INSERT) {
91 			sfc_err(sa,
92 				"VLAN offload is not supported by %s datapath",
93 				sa->dp_tx->dp.name);
94 			rc = EINVAL;
95 		}
96 	}
97 
98 	if ((flags & ETH_TXQ_FLAGS_NOXSUMSCTP) == 0) {
99 		sfc_err(sa, "SCTP offload is not supported");
100 		rc = EINVAL;
101 	}
102 
103 	/* We either perform both TCP and UDP offload, or no offload at all */
104 	if (((flags & ETH_TXQ_FLAGS_NOXSUMTCP) == 0) !=
105 	    ((flags & ETH_TXQ_FLAGS_NOXSUMUDP) == 0)) {
106 		sfc_err(sa, "TCP and UDP offloads can't be set independently");
107 		rc = EINVAL;
108 	}
109 
110 	return rc;
111 }
112 
113 void
114 sfc_tx_qflush_done(struct sfc_txq *txq)
115 {
116 	txq->state |= SFC_TXQ_FLUSHED;
117 	txq->state &= ~SFC_TXQ_FLUSHING;
118 }
119 
120 int
121 sfc_tx_qinit(struct sfc_adapter *sa, unsigned int sw_index,
122 	     uint16_t nb_tx_desc, unsigned int socket_id,
123 	     const struct rte_eth_txconf *tx_conf)
124 {
125 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
126 	unsigned int txq_entries;
127 	unsigned int evq_entries;
128 	unsigned int txq_max_fill_level;
129 	struct sfc_txq_info *txq_info;
130 	struct sfc_evq *evq;
131 	struct sfc_txq *txq;
132 	int rc = 0;
133 	struct sfc_dp_tx_qcreate_info info;
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 	rc = sfc_tx_qcheck_conf(sa, txq_max_fill_level, tx_conf);
147 	if (rc != 0)
148 		goto fail_bad_conf;
149 
150 	SFC_ASSERT(sw_index < sa->txq_count);
151 	txq_info = &sa->txq_info[sw_index];
152 
153 	txq_info->entries = txq_entries;
154 
155 	rc = sfc_ev_qinit(sa, SFC_EVQ_TYPE_TX, sw_index,
156 			  evq_entries, socket_id, &evq);
157 	if (rc != 0)
158 		goto fail_ev_qinit;
159 
160 	rc = ENOMEM;
161 	txq = rte_zmalloc_socket("sfc-txq", sizeof(*txq), 0, socket_id);
162 	if (txq == NULL)
163 		goto fail_txq_alloc;
164 
165 	txq_info->txq = txq;
166 
167 	txq->hw_index = sw_index;
168 	txq->evq = evq;
169 	txq->free_thresh =
170 		(tx_conf->tx_free_thresh) ? tx_conf->tx_free_thresh :
171 		SFC_TX_DEFAULT_FREE_THRESH;
172 	txq->flags = tx_conf->txq_flags;
173 
174 	rc = sfc_dma_alloc(sa, "txq", sw_index, EFX_TXQ_SIZE(txq_info->entries),
175 			   socket_id, &txq->mem);
176 	if (rc != 0)
177 		goto fail_dma_alloc;
178 
179 	memset(&info, 0, sizeof(info));
180 	info.max_fill_level = txq_max_fill_level;
181 	info.free_thresh = txq->free_thresh;
182 	info.flags = tx_conf->txq_flags;
183 	info.txq_entries = txq_info->entries;
184 	info.dma_desc_size_max = encp->enc_tx_dma_desc_size_max;
185 	info.txq_hw_ring = txq->mem.esm_base;
186 	info.evq_entries = evq_entries;
187 	info.evq_hw_ring = evq->mem.esm_base;
188 	info.hw_index = txq->hw_index;
189 	info.mem_bar = sa->mem_bar.esb_base;
190 
191 	rc = sa->dp_tx->qcreate(sa->eth_dev->data->port_id, sw_index,
192 				&RTE_ETH_DEV_TO_PCI(sa->eth_dev)->addr,
193 				socket_id, &info, &txq->dp);
194 	if (rc != 0)
195 		goto fail_dp_tx_qinit;
196 
197 	evq->dp_txq = txq->dp;
198 
199 	txq->state = SFC_TXQ_INITIALIZED;
200 
201 	txq_info->deferred_start = (tx_conf->tx_deferred_start != 0);
202 
203 	return 0;
204 
205 fail_dp_tx_qinit:
206 	sfc_dma_free(sa, &txq->mem);
207 
208 fail_dma_alloc:
209 	txq_info->txq = NULL;
210 	rte_free(txq);
211 
212 fail_txq_alloc:
213 	sfc_ev_qfini(evq);
214 
215 fail_ev_qinit:
216 	txq_info->entries = 0;
217 
218 fail_bad_conf:
219 fail_size_up_rings:
220 	sfc_log_init(sa, "failed (TxQ = %u, rc = %d)", sw_index, rc);
221 	return rc;
222 }
223 
224 void
225 sfc_tx_qfini(struct sfc_adapter *sa, unsigned int sw_index)
226 {
227 	struct sfc_txq_info *txq_info;
228 	struct sfc_txq *txq;
229 
230 	sfc_log_init(sa, "TxQ = %u", sw_index);
231 
232 	SFC_ASSERT(sw_index < sa->txq_count);
233 	txq_info = &sa->txq_info[sw_index];
234 
235 	txq = txq_info->txq;
236 	SFC_ASSERT(txq != NULL);
237 	SFC_ASSERT(txq->state == SFC_TXQ_INITIALIZED);
238 
239 	sa->dp_tx->qdestroy(txq->dp);
240 	txq->dp = NULL;
241 
242 	txq_info->txq = NULL;
243 	txq_info->entries = 0;
244 
245 	sfc_dma_free(sa, &txq->mem);
246 
247 	sfc_ev_qfini(txq->evq);
248 	txq->evq = NULL;
249 
250 	rte_free(txq);
251 }
252 
253 static int
254 sfc_tx_qinit_info(struct sfc_adapter *sa, unsigned int sw_index)
255 {
256 	sfc_log_init(sa, "TxQ = %u", sw_index);
257 
258 	return 0;
259 }
260 
261 static int
262 sfc_tx_check_mode(struct sfc_adapter *sa, const struct rte_eth_txmode *txmode)
263 {
264 	int rc = 0;
265 
266 	switch (txmode->mq_mode) {
267 	case ETH_MQ_TX_NONE:
268 		break;
269 	default:
270 		sfc_err(sa, "Tx multi-queue mode %u not supported",
271 			txmode->mq_mode);
272 		rc = EINVAL;
273 	}
274 
275 	/*
276 	 * These features are claimed to be i40e-specific,
277 	 * but it does make sense to double-check their absence
278 	 */
279 	if (txmode->hw_vlan_reject_tagged) {
280 		sfc_err(sa, "Rejecting tagged packets not supported");
281 		rc = EINVAL;
282 	}
283 
284 	if (txmode->hw_vlan_reject_untagged) {
285 		sfc_err(sa, "Rejecting untagged packets not supported");
286 		rc = EINVAL;
287 	}
288 
289 	if (txmode->hw_vlan_insert_pvid) {
290 		sfc_err(sa, "Port-based VLAN insertion not supported");
291 		rc = EINVAL;
292 	}
293 
294 	return rc;
295 }
296 
297 /**
298  * Destroy excess queues that are no longer needed after reconfiguration
299  * or complete close.
300  */
301 static void
302 sfc_tx_fini_queues(struct sfc_adapter *sa, unsigned int nb_tx_queues)
303 {
304 	int sw_index;
305 
306 	SFC_ASSERT(nb_tx_queues <= sa->txq_count);
307 
308 	sw_index = sa->txq_count;
309 	while (--sw_index >= (int)nb_tx_queues) {
310 		if (sa->txq_info[sw_index].txq != NULL)
311 			sfc_tx_qfini(sa, sw_index);
312 	}
313 
314 	sa->txq_count = nb_tx_queues;
315 }
316 
317 int
318 sfc_tx_configure(struct sfc_adapter *sa)
319 {
320 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
321 	const struct rte_eth_conf *dev_conf = &sa->eth_dev->data->dev_conf;
322 	const unsigned int nb_tx_queues = sa->eth_dev->data->nb_tx_queues;
323 	int rc = 0;
324 
325 	sfc_log_init(sa, "nb_tx_queues=%u (old %u)",
326 		     nb_tx_queues, sa->txq_count);
327 
328 	/*
329 	 * The datapath implementation assumes absence of boundary
330 	 * limits on Tx DMA descriptors. Addition of these checks on
331 	 * datapath would simply make the datapath slower.
332 	 */
333 	if (encp->enc_tx_dma_desc_boundary != 0) {
334 		rc = ENOTSUP;
335 		goto fail_tx_dma_desc_boundary;
336 	}
337 
338 	rc = sfc_tx_check_mode(sa, &dev_conf->txmode);
339 	if (rc != 0)
340 		goto fail_check_mode;
341 
342 	if (nb_tx_queues == sa->txq_count)
343 		goto done;
344 
345 	if (sa->txq_info == NULL) {
346 		sa->txq_info = rte_calloc_socket("sfc-txqs", nb_tx_queues,
347 						 sizeof(sa->txq_info[0]), 0,
348 						 sa->socket_id);
349 		if (sa->txq_info == NULL)
350 			goto fail_txqs_alloc;
351 	} else {
352 		struct sfc_txq_info *new_txq_info;
353 
354 		if (nb_tx_queues < sa->txq_count)
355 			sfc_tx_fini_queues(sa, nb_tx_queues);
356 
357 		new_txq_info =
358 			rte_realloc(sa->txq_info,
359 				    nb_tx_queues * sizeof(sa->txq_info[0]), 0);
360 		if (new_txq_info == NULL && nb_tx_queues > 0)
361 			goto fail_txqs_realloc;
362 
363 		sa->txq_info = new_txq_info;
364 		if (nb_tx_queues > sa->txq_count)
365 			memset(&sa->txq_info[sa->txq_count], 0,
366 			       (nb_tx_queues - sa->txq_count) *
367 			       sizeof(sa->txq_info[0]));
368 	}
369 
370 	while (sa->txq_count < nb_tx_queues) {
371 		rc = sfc_tx_qinit_info(sa, sa->txq_count);
372 		if (rc != 0)
373 			goto fail_tx_qinit_info;
374 
375 		sa->txq_count++;
376 	}
377 
378 done:
379 	return 0;
380 
381 fail_tx_qinit_info:
382 fail_txqs_realloc:
383 fail_txqs_alloc:
384 	sfc_tx_close(sa);
385 
386 fail_check_mode:
387 fail_tx_dma_desc_boundary:
388 	sfc_log_init(sa, "failed (rc = %d)", rc);
389 	return rc;
390 }
391 
392 void
393 sfc_tx_close(struct sfc_adapter *sa)
394 {
395 	sfc_tx_fini_queues(sa, 0);
396 
397 	rte_free(sa->txq_info);
398 	sa->txq_info = NULL;
399 }
400 
401 int
402 sfc_tx_qstart(struct sfc_adapter *sa, unsigned int sw_index)
403 {
404 	const efx_nic_cfg_t *encp = efx_nic_cfg_get(sa->nic);
405 	struct rte_eth_dev_data *dev_data;
406 	struct sfc_txq_info *txq_info;
407 	struct sfc_txq *txq;
408 	struct sfc_evq *evq;
409 	uint16_t flags;
410 	unsigned int desc_index;
411 	int rc = 0;
412 
413 	sfc_log_init(sa, "TxQ = %u", sw_index);
414 
415 	SFC_ASSERT(sw_index < sa->txq_count);
416 	txq_info = &sa->txq_info[sw_index];
417 
418 	txq = txq_info->txq;
419 
420 	SFC_ASSERT(txq->state == SFC_TXQ_INITIALIZED);
421 
422 	evq = txq->evq;
423 
424 	rc = sfc_ev_qstart(evq, sfc_evq_index_by_txq_sw_index(sa, sw_index));
425 	if (rc != 0)
426 		goto fail_ev_qstart;
427 
428 	/*
429 	 * It seems that DPDK has no controls regarding IPv4 offloads,
430 	 * hence, we always enable it here
431 	 */
432 	if ((txq->flags & ETH_TXQ_FLAGS_NOXSUMTCP) ||
433 	    (txq->flags & ETH_TXQ_FLAGS_NOXSUMUDP)) {
434 		flags = EFX_TXQ_CKSUM_IPV4;
435 
436 		if (encp->enc_tunnel_encapsulations_supported != 0)
437 			flags |= EFX_TXQ_CKSUM_INNER_IPV4;
438 	} else {
439 		flags = EFX_TXQ_CKSUM_IPV4 | EFX_TXQ_CKSUM_TCPUDP;
440 
441 		if (encp->enc_tunnel_encapsulations_supported != 0)
442 			flags |= EFX_TXQ_CKSUM_INNER_IPV4 |
443 				 EFX_TXQ_CKSUM_INNER_TCPUDP;
444 
445 		if (sa->tso)
446 			flags |= EFX_TXQ_FATSOV2;
447 	}
448 
449 	rc = efx_tx_qcreate(sa->nic, sw_index, 0, &txq->mem,
450 			    txq_info->entries, 0 /* not used on EF10 */,
451 			    flags, evq->common,
452 			    &txq->common, &desc_index);
453 	if (rc != 0) {
454 		if (sa->tso && (rc == ENOSPC))
455 			sfc_err(sa, "ran out of TSO contexts");
456 
457 		goto fail_tx_qcreate;
458 	}
459 
460 	efx_tx_qenable(txq->common);
461 
462 	txq->state |= SFC_TXQ_STARTED;
463 
464 	rc = sa->dp_tx->qstart(txq->dp, evq->read_ptr, desc_index);
465 	if (rc != 0)
466 		goto fail_dp_qstart;
467 
468 	/*
469 	 * It seems to be used by DPDK for debug purposes only ('rte_ether')
470 	 */
471 	dev_data = sa->eth_dev->data;
472 	dev_data->tx_queue_state[sw_index] = RTE_ETH_QUEUE_STATE_STARTED;
473 
474 	return 0;
475 
476 fail_dp_qstart:
477 	txq->state = SFC_TXQ_INITIALIZED;
478 	efx_tx_qdestroy(txq->common);
479 
480 fail_tx_qcreate:
481 	sfc_ev_qstop(evq);
482 
483 fail_ev_qstart:
484 	return rc;
485 }
486 
487 void
488 sfc_tx_qstop(struct sfc_adapter *sa, unsigned int sw_index)
489 {
490 	struct rte_eth_dev_data *dev_data;
491 	struct sfc_txq_info *txq_info;
492 	struct sfc_txq *txq;
493 	unsigned int retry_count;
494 	unsigned int wait_count;
495 	int rc;
496 
497 	sfc_log_init(sa, "TxQ = %u", sw_index);
498 
499 	SFC_ASSERT(sw_index < sa->txq_count);
500 	txq_info = &sa->txq_info[sw_index];
501 
502 	txq = txq_info->txq;
503 
504 	if (txq->state == SFC_TXQ_INITIALIZED)
505 		return;
506 
507 	SFC_ASSERT(txq->state & SFC_TXQ_STARTED);
508 
509 	sa->dp_tx->qstop(txq->dp, &txq->evq->read_ptr);
510 
511 	/*
512 	 * Retry TX queue flushing in case of flush failed or
513 	 * timeout; in the worst case it can delay for 6 seconds
514 	 */
515 	for (retry_count = 0;
516 	     ((txq->state & SFC_TXQ_FLUSHED) == 0) &&
517 	     (retry_count < SFC_TX_QFLUSH_ATTEMPTS);
518 	     ++retry_count) {
519 		rc = efx_tx_qflush(txq->common);
520 		if (rc != 0) {
521 			txq->state |= (rc == EALREADY) ?
522 				SFC_TXQ_FLUSHED : SFC_TXQ_FLUSH_FAILED;
523 			break;
524 		}
525 
526 		/*
527 		 * Wait for TX queue flush done or flush failed event at least
528 		 * SFC_TX_QFLUSH_POLL_WAIT_MS milliseconds and not more
529 		 * than 2 seconds (SFC_TX_QFLUSH_POLL_WAIT_MS multiplied
530 		 * by SFC_TX_QFLUSH_POLL_ATTEMPTS)
531 		 */
532 		wait_count = 0;
533 		do {
534 			rte_delay_ms(SFC_TX_QFLUSH_POLL_WAIT_MS);
535 			sfc_ev_qpoll(txq->evq);
536 		} while ((txq->state & SFC_TXQ_FLUSHING) &&
537 			 wait_count++ < SFC_TX_QFLUSH_POLL_ATTEMPTS);
538 
539 		if (txq->state & SFC_TXQ_FLUSHING)
540 			sfc_err(sa, "TxQ %u flush timed out", sw_index);
541 
542 		if (txq->state & SFC_TXQ_FLUSHED)
543 			sfc_info(sa, "TxQ %u flushed", sw_index);
544 	}
545 
546 	sa->dp_tx->qreap(txq->dp);
547 
548 	txq->state = SFC_TXQ_INITIALIZED;
549 
550 	efx_tx_qdestroy(txq->common);
551 
552 	sfc_ev_qstop(txq->evq);
553 
554 	/*
555 	 * It seems to be used by DPDK for debug purposes only ('rte_ether')
556 	 */
557 	dev_data = sa->eth_dev->data;
558 	dev_data->tx_queue_state[sw_index] = RTE_ETH_QUEUE_STATE_STOPPED;
559 }
560 
561 int
562 sfc_tx_start(struct sfc_adapter *sa)
563 {
564 	unsigned int sw_index;
565 	int rc = 0;
566 
567 	sfc_log_init(sa, "txq_count = %u", sa->txq_count);
568 
569 	if (sa->tso) {
570 		if (!efx_nic_cfg_get(sa->nic)->enc_fw_assisted_tso_v2_enabled) {
571 			sfc_warn(sa, "TSO support was unable to be restored");
572 			sa->tso = B_FALSE;
573 		}
574 	}
575 
576 	rc = efx_tx_init(sa->nic);
577 	if (rc != 0)
578 		goto fail_efx_tx_init;
579 
580 	for (sw_index = 0; sw_index < sa->txq_count; ++sw_index) {
581 		if (!(sa->txq_info[sw_index].deferred_start) ||
582 		    sa->txq_info[sw_index].deferred_started) {
583 			rc = sfc_tx_qstart(sa, sw_index);
584 			if (rc != 0)
585 				goto fail_tx_qstart;
586 		}
587 	}
588 
589 	return 0;
590 
591 fail_tx_qstart:
592 	while (sw_index-- > 0)
593 		sfc_tx_qstop(sa, sw_index);
594 
595 	efx_tx_fini(sa->nic);
596 
597 fail_efx_tx_init:
598 	sfc_log_init(sa, "failed (rc = %d)", rc);
599 	return rc;
600 }
601 
602 void
603 sfc_tx_stop(struct sfc_adapter *sa)
604 {
605 	unsigned int sw_index;
606 
607 	sfc_log_init(sa, "txq_count = %u", sa->txq_count);
608 
609 	sw_index = sa->txq_count;
610 	while (sw_index-- > 0) {
611 		if (sa->txq_info[sw_index].txq != NULL)
612 			sfc_tx_qstop(sa, sw_index);
613 	}
614 
615 	efx_tx_fini(sa->nic);
616 }
617 
618 static void
619 sfc_efx_tx_reap(struct sfc_efx_txq *txq)
620 {
621 	unsigned int completed;
622 
623 	sfc_ev_qpoll(txq->evq);
624 
625 	for (completed = txq->completed;
626 	     completed != txq->pending; completed++) {
627 		struct sfc_efx_tx_sw_desc *txd;
628 
629 		txd = &txq->sw_ring[completed & txq->ptr_mask];
630 
631 		if (txd->mbuf != NULL) {
632 			rte_pktmbuf_free(txd->mbuf);
633 			txd->mbuf = NULL;
634 		}
635 	}
636 
637 	txq->completed = completed;
638 }
639 
640 /*
641  * The function is used to insert or update VLAN tag;
642  * the firmware has state of the firmware tag to insert per TxQ
643  * (controlled by option descriptors), hence, if the tag of the
644  * packet to be sent is different from one remembered by the firmware,
645  * the function will update it
646  */
647 static unsigned int
648 sfc_efx_tx_maybe_insert_tag(struct sfc_efx_txq *txq, struct rte_mbuf *m,
649 			    efx_desc_t **pend)
650 {
651 	uint16_t this_tag = ((m->ol_flags & PKT_TX_VLAN_PKT) ?
652 			     m->vlan_tci : 0);
653 
654 	if (this_tag == txq->hw_vlan_tci)
655 		return 0;
656 
657 	/*
658 	 * The expression inside SFC_ASSERT() is not desired to be checked in
659 	 * a non-debug build because it might be too expensive on the data path
660 	 */
661 	SFC_ASSERT(efx_nic_cfg_get(txq->evq->sa->nic)->enc_hw_tx_insert_vlan_enabled);
662 
663 	efx_tx_qdesc_vlantci_create(txq->common, rte_cpu_to_be_16(this_tag),
664 				    *pend);
665 	(*pend)++;
666 	txq->hw_vlan_tci = this_tag;
667 
668 	return 1;
669 }
670 
671 static uint16_t
672 sfc_efx_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
673 {
674 	struct sfc_dp_txq *dp_txq = (struct sfc_dp_txq *)tx_queue;
675 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
676 	unsigned int added = txq->added;
677 	unsigned int pushed = added;
678 	unsigned int pkts_sent = 0;
679 	efx_desc_t *pend = &txq->pend_desc[0];
680 	const unsigned int hard_max_fill = txq->max_fill_level;
681 	const unsigned int soft_max_fill = hard_max_fill - txq->free_thresh;
682 	unsigned int fill_level = added - txq->completed;
683 	boolean_t reap_done;
684 	int rc __rte_unused;
685 	struct rte_mbuf **pktp;
686 
687 	if (unlikely((txq->flags & SFC_EFX_TXQ_FLAG_RUNNING) == 0))
688 		goto done;
689 
690 	/*
691 	 * If insufficient space for a single packet is present,
692 	 * we should reap; otherwise, we shouldn't do that all the time
693 	 * to avoid latency increase
694 	 */
695 	reap_done = (fill_level > soft_max_fill);
696 
697 	if (reap_done) {
698 		sfc_efx_tx_reap(txq);
699 		/*
700 		 * Recalculate fill level since 'txq->completed'
701 		 * might have changed on reap
702 		 */
703 		fill_level = added - txq->completed;
704 	}
705 
706 	for (pkts_sent = 0, pktp = &tx_pkts[0];
707 	     (pkts_sent < nb_pkts) && (fill_level <= soft_max_fill);
708 	     pkts_sent++, pktp++) {
709 		struct rte_mbuf		*m_seg = *pktp;
710 		size_t			pkt_len = m_seg->pkt_len;
711 		unsigned int		pkt_descs = 0;
712 		size_t			in_off = 0;
713 
714 		/*
715 		 * Here VLAN TCI is expected to be zero in case if no
716 		 * DEV_TX_VLAN_OFFLOAD capability is advertised;
717 		 * if the calling app ignores the absence of
718 		 * DEV_TX_VLAN_OFFLOAD and pushes VLAN TCI, then
719 		 * TX_ERROR will occur
720 		 */
721 		pkt_descs += sfc_efx_tx_maybe_insert_tag(txq, m_seg, &pend);
722 
723 		if (m_seg->ol_flags & PKT_TX_TCP_SEG) {
724 			/*
725 			 * We expect correct 'pkt->l[2, 3, 4]_len' values
726 			 * to be set correctly by the caller
727 			 */
728 			if (sfc_efx_tso_do(txq, added, &m_seg, &in_off, &pend,
729 					   &pkt_descs, &pkt_len) != 0) {
730 				/* We may have reached this place for
731 				 * one of the following reasons:
732 				 *
733 				 * 1) Packet header length is greater
734 				 *    than SFC_TSOH_STD_LEN
735 				 * 2) TCP header starts at more then
736 				 *    208 bytes into the frame
737 				 *
738 				 * We will deceive RTE saying that we have sent
739 				 * the packet, but we will actually drop it.
740 				 * Hence, we should revert 'pend' to the
741 				 * previous state (in case we have added
742 				 * VLAN descriptor) and start processing
743 				 * another one packet. But the original
744 				 * mbuf shouldn't be orphaned
745 				 */
746 				pend -= pkt_descs;
747 
748 				rte_pktmbuf_free(*pktp);
749 
750 				continue;
751 			}
752 
753 			/*
754 			 * We've only added 2 FATSOv2 option descriptors
755 			 * and 1 descriptor for the linearized packet header.
756 			 * The outstanding work will be done in the same manner
757 			 * as for the usual non-TSO path
758 			 */
759 		}
760 
761 		for (; m_seg != NULL; m_seg = m_seg->next) {
762 			efsys_dma_addr_t	next_frag;
763 			size_t			seg_len;
764 
765 			seg_len = m_seg->data_len;
766 			next_frag = rte_mbuf_data_iova(m_seg);
767 
768 			/*
769 			 * If we've started TSO transaction few steps earlier,
770 			 * we'll skip packet header using an offset in the
771 			 * current segment (which has been set to the
772 			 * first one containing payload)
773 			 */
774 			seg_len -= in_off;
775 			next_frag += in_off;
776 			in_off = 0;
777 
778 			do {
779 				efsys_dma_addr_t	frag_addr = next_frag;
780 				size_t			frag_len;
781 
782 				/*
783 				 * It is assumed here that there is no
784 				 * limitation on address boundary
785 				 * crossing by DMA descriptor.
786 				 */
787 				frag_len = MIN(seg_len, txq->dma_desc_size_max);
788 				next_frag += frag_len;
789 				seg_len -= frag_len;
790 				pkt_len -= frag_len;
791 
792 				efx_tx_qdesc_dma_create(txq->common,
793 							frag_addr, frag_len,
794 							(pkt_len == 0),
795 							pend++);
796 
797 				pkt_descs++;
798 			} while (seg_len != 0);
799 		}
800 
801 		added += pkt_descs;
802 
803 		fill_level += pkt_descs;
804 		if (unlikely(fill_level > hard_max_fill)) {
805 			/*
806 			 * Our estimation for maximum number of descriptors
807 			 * required to send a packet seems to be wrong.
808 			 * Try to reap (if we haven't yet).
809 			 */
810 			if (!reap_done) {
811 				sfc_efx_tx_reap(txq);
812 				reap_done = B_TRUE;
813 				fill_level = added - txq->completed;
814 				if (fill_level > hard_max_fill) {
815 					pend -= pkt_descs;
816 					break;
817 				}
818 			} else {
819 				pend -= pkt_descs;
820 				break;
821 			}
822 		}
823 
824 		/* Assign mbuf to the last used desc */
825 		txq->sw_ring[(added - 1) & txq->ptr_mask].mbuf = *pktp;
826 	}
827 
828 	if (likely(pkts_sent > 0)) {
829 		rc = efx_tx_qdesc_post(txq->common, txq->pend_desc,
830 				       pend - &txq->pend_desc[0],
831 				       txq->completed, &txq->added);
832 		SFC_ASSERT(rc == 0);
833 
834 		if (likely(pushed != txq->added))
835 			efx_tx_qpush(txq->common, txq->added, pushed);
836 	}
837 
838 #if SFC_TX_XMIT_PKTS_REAP_AT_LEAST_ONCE
839 	if (!reap_done)
840 		sfc_efx_tx_reap(txq);
841 #endif
842 
843 done:
844 	return pkts_sent;
845 }
846 
847 struct sfc_txq *
848 sfc_txq_by_dp_txq(const struct sfc_dp_txq *dp_txq)
849 {
850 	const struct sfc_dp_queue *dpq = &dp_txq->dpq;
851 	struct rte_eth_dev *eth_dev;
852 	struct sfc_adapter *sa;
853 	struct sfc_txq *txq;
854 
855 	SFC_ASSERT(rte_eth_dev_is_valid_port(dpq->port_id));
856 	eth_dev = &rte_eth_devices[dpq->port_id];
857 
858 	sa = eth_dev->data->dev_private;
859 
860 	SFC_ASSERT(dpq->queue_id < sa->txq_count);
861 	txq = sa->txq_info[dpq->queue_id].txq;
862 
863 	SFC_ASSERT(txq != NULL);
864 	return txq;
865 }
866 
867 static sfc_dp_tx_qsize_up_rings_t sfc_efx_tx_qsize_up_rings;
868 static int
869 sfc_efx_tx_qsize_up_rings(uint16_t nb_tx_desc,
870 			  unsigned int *txq_entries,
871 			  unsigned int *evq_entries,
872 			  unsigned int *txq_max_fill_level)
873 {
874 	*txq_entries = nb_tx_desc;
875 	*evq_entries = nb_tx_desc;
876 	*txq_max_fill_level = EFX_TXQ_LIMIT(*txq_entries);
877 	return 0;
878 }
879 
880 static sfc_dp_tx_qcreate_t sfc_efx_tx_qcreate;
881 static int
882 sfc_efx_tx_qcreate(uint16_t port_id, uint16_t queue_id,
883 		   const struct rte_pci_addr *pci_addr,
884 		   int socket_id,
885 		   const struct sfc_dp_tx_qcreate_info *info,
886 		   struct sfc_dp_txq **dp_txqp)
887 {
888 	struct sfc_efx_txq *txq;
889 	struct sfc_txq *ctrl_txq;
890 	int rc;
891 
892 	rc = ENOMEM;
893 	txq = rte_zmalloc_socket("sfc-efx-txq", sizeof(*txq),
894 				 RTE_CACHE_LINE_SIZE, socket_id);
895 	if (txq == NULL)
896 		goto fail_txq_alloc;
897 
898 	sfc_dp_queue_init(&txq->dp.dpq, port_id, queue_id, pci_addr);
899 
900 	rc = ENOMEM;
901 	txq->pend_desc = rte_calloc_socket("sfc-efx-txq-pend-desc",
902 					   EFX_TXQ_LIMIT(info->txq_entries),
903 					   sizeof(*txq->pend_desc), 0,
904 					   socket_id);
905 	if (txq->pend_desc == NULL)
906 		goto fail_pend_desc_alloc;
907 
908 	rc = ENOMEM;
909 	txq->sw_ring = rte_calloc_socket("sfc-efx-txq-sw_ring",
910 					 info->txq_entries,
911 					 sizeof(*txq->sw_ring),
912 					 RTE_CACHE_LINE_SIZE, socket_id);
913 	if (txq->sw_ring == NULL)
914 		goto fail_sw_ring_alloc;
915 
916 	ctrl_txq = sfc_txq_by_dp_txq(&txq->dp);
917 	if (ctrl_txq->evq->sa->tso) {
918 		rc = sfc_efx_tso_alloc_tsoh_objs(txq->sw_ring,
919 						 info->txq_entries, socket_id);
920 		if (rc != 0)
921 			goto fail_alloc_tsoh_objs;
922 	}
923 
924 	txq->evq = ctrl_txq->evq;
925 	txq->ptr_mask = info->txq_entries - 1;
926 	txq->max_fill_level = info->max_fill_level;
927 	txq->free_thresh = info->free_thresh;
928 	txq->dma_desc_size_max = info->dma_desc_size_max;
929 
930 	*dp_txqp = &txq->dp;
931 	return 0;
932 
933 fail_alloc_tsoh_objs:
934 	rte_free(txq->sw_ring);
935 
936 fail_sw_ring_alloc:
937 	rte_free(txq->pend_desc);
938 
939 fail_pend_desc_alloc:
940 	rte_free(txq);
941 
942 fail_txq_alloc:
943 	return rc;
944 }
945 
946 static sfc_dp_tx_qdestroy_t sfc_efx_tx_qdestroy;
947 static void
948 sfc_efx_tx_qdestroy(struct sfc_dp_txq *dp_txq)
949 {
950 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
951 
952 	sfc_efx_tso_free_tsoh_objs(txq->sw_ring, txq->ptr_mask + 1);
953 	rte_free(txq->sw_ring);
954 	rte_free(txq->pend_desc);
955 	rte_free(txq);
956 }
957 
958 static sfc_dp_tx_qstart_t sfc_efx_tx_qstart;
959 static int
960 sfc_efx_tx_qstart(struct sfc_dp_txq *dp_txq,
961 		  __rte_unused unsigned int evq_read_ptr,
962 		  unsigned int txq_desc_index)
963 {
964 	/* libefx-based datapath is specific to libefx-based PMD */
965 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
966 	struct sfc_txq *ctrl_txq = sfc_txq_by_dp_txq(dp_txq);
967 
968 	txq->common = ctrl_txq->common;
969 
970 	txq->pending = txq->completed = txq->added = txq_desc_index;
971 	txq->hw_vlan_tci = 0;
972 
973 	txq->flags |= (SFC_EFX_TXQ_FLAG_STARTED | SFC_EFX_TXQ_FLAG_RUNNING);
974 
975 	return 0;
976 }
977 
978 static sfc_dp_tx_qstop_t sfc_efx_tx_qstop;
979 static void
980 sfc_efx_tx_qstop(struct sfc_dp_txq *dp_txq,
981 		 __rte_unused unsigned int *evq_read_ptr)
982 {
983 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
984 
985 	txq->flags &= ~SFC_EFX_TXQ_FLAG_RUNNING;
986 }
987 
988 static sfc_dp_tx_qreap_t sfc_efx_tx_qreap;
989 static void
990 sfc_efx_tx_qreap(struct sfc_dp_txq *dp_txq)
991 {
992 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
993 	unsigned int txds;
994 
995 	sfc_efx_tx_reap(txq);
996 
997 	for (txds = 0; txds <= txq->ptr_mask; txds++) {
998 		if (txq->sw_ring[txds].mbuf != NULL) {
999 			rte_pktmbuf_free(txq->sw_ring[txds].mbuf);
1000 			txq->sw_ring[txds].mbuf = NULL;
1001 		}
1002 	}
1003 
1004 	txq->flags &= ~SFC_EFX_TXQ_FLAG_STARTED;
1005 }
1006 
1007 static sfc_dp_tx_qdesc_status_t sfc_efx_tx_qdesc_status;
1008 static int
1009 sfc_efx_tx_qdesc_status(struct sfc_dp_txq *dp_txq, uint16_t offset)
1010 {
1011 	struct sfc_efx_txq *txq = sfc_efx_txq_by_dp_txq(dp_txq);
1012 
1013 	if (unlikely(offset > txq->ptr_mask))
1014 		return -EINVAL;
1015 
1016 	if (unlikely(offset >= txq->max_fill_level))
1017 		return RTE_ETH_TX_DESC_UNAVAIL;
1018 
1019 	/*
1020 	 * Poll EvQ to derive up-to-date 'txq->pending' figure;
1021 	 * it is required for the queue to be running, but the
1022 	 * check is omitted because API design assumes that it
1023 	 * is the duty of the caller to satisfy all conditions
1024 	 */
1025 	SFC_ASSERT((txq->flags & SFC_EFX_TXQ_FLAG_RUNNING) ==
1026 		   SFC_EFX_TXQ_FLAG_RUNNING);
1027 	sfc_ev_qpoll(txq->evq);
1028 
1029 	/*
1030 	 * Ring tail is 'txq->pending', and although descriptors
1031 	 * between 'txq->completed' and 'txq->pending' are still
1032 	 * in use by the driver, they should be reported as DONE
1033 	 */
1034 	if (unlikely(offset < (txq->added - txq->pending)))
1035 		return RTE_ETH_TX_DESC_FULL;
1036 
1037 	/*
1038 	 * There is no separate return value for unused descriptors;
1039 	 * the latter will be reported as DONE because genuine DONE
1040 	 * descriptors will be freed anyway in SW on the next burst
1041 	 */
1042 	return RTE_ETH_TX_DESC_DONE;
1043 }
1044 
1045 struct sfc_dp_tx sfc_efx_tx = {
1046 	.dp = {
1047 		.name		= SFC_KVARG_DATAPATH_EFX,
1048 		.type		= SFC_DP_TX,
1049 		.hw_fw_caps	= 0,
1050 	},
1051 	.features		= SFC_DP_TX_FEAT_VLAN_INSERT |
1052 				  SFC_DP_TX_FEAT_TSO |
1053 				  SFC_DP_TX_FEAT_MULTI_POOL |
1054 				  SFC_DP_TX_FEAT_REFCNT |
1055 				  SFC_DP_TX_FEAT_MULTI_SEG,
1056 	.qsize_up_rings		= sfc_efx_tx_qsize_up_rings,
1057 	.qcreate		= sfc_efx_tx_qcreate,
1058 	.qdestroy		= sfc_efx_tx_qdestroy,
1059 	.qstart			= sfc_efx_tx_qstart,
1060 	.qstop			= sfc_efx_tx_qstop,
1061 	.qreap			= sfc_efx_tx_qreap,
1062 	.qdesc_status		= sfc_efx_tx_qdesc_status,
1063 	.pkt_burst		= sfc_efx_xmit_pkts,
1064 };
1065