xref: /dpdk/drivers/net/octeon_ep/otx_ep_rxtx.c (revision e9fd1ebf981f361844aea9ec94e17f4bda5e1479)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(C) 2021 Marvell.
3  */
4 
5 #include <unistd.h>
6 #include <assert.h>
7 #include <rte_eal.h>
8 #include <rte_mempool.h>
9 #include <rte_mbuf.h>
10 #include <rte_io.h>
11 #include <rte_net.h>
12 #include <ethdev_pci.h>
13 
14 #include "cnxk_ep_rx.h"
15 #include "otx_ep_common.h"
16 #include "otx_ep_vf.h"
17 #include "otx_ep_rxtx.h"
18 
19 static void
20 otx_ep_dmazone_free(const struct rte_memzone *mz)
21 {
22 	const struct rte_memzone *mz_tmp;
23 	int ret = 0;
24 
25 	if (mz == NULL) {
26 		otx_ep_err("Memzone: NULL\n");
27 		return;
28 	}
29 
30 	mz_tmp = rte_memzone_lookup(mz->name);
31 	if (mz_tmp == NULL) {
32 		otx_ep_err("Memzone %s Not Found\n", mz->name);
33 		return;
34 	}
35 
36 	ret = rte_memzone_free(mz);
37 	if (ret)
38 		otx_ep_err("Memzone free failed : ret = %d\n", ret);
39 }
40 
41 /* Free IQ resources */
42 int
43 otx_ep_delete_iqs(struct otx_ep_device *otx_ep, uint32_t iq_no)
44 {
45 	struct otx_ep_instr_queue *iq;
46 	uint32_t i;
47 
48 	iq = otx_ep->instr_queue[iq_no];
49 	if (iq == NULL) {
50 		otx_ep_err("Invalid IQ[%d]\n", iq_no);
51 		return -EINVAL;
52 	}
53 
54 	if (iq->req_list) {
55 		for (i = 0; i < iq->nb_desc; i++)
56 			rte_free(iq->req_list[i].finfo.g.sg);
57 		rte_free(iq->req_list);
58 	}
59 
60 	iq->req_list = NULL;
61 
62 	if (iq->iq_mz) {
63 		otx_ep_dmazone_free(iq->iq_mz);
64 		iq->iq_mz = NULL;
65 	}
66 
67 	rte_free(otx_ep->instr_queue[iq_no]);
68 	otx_ep->instr_queue[iq_no] = NULL;
69 
70 	otx_ep->nb_tx_queues--;
71 
72 	otx_ep_info("IQ[%d] is deleted\n", iq_no);
73 
74 	return 0;
75 }
76 
77 /* IQ initialization */
78 static int
79 otx_ep_init_instr_queue(struct otx_ep_device *otx_ep, int iq_no, int num_descs,
80 		     unsigned int socket_id)
81 {
82 	const struct otx_ep_config *conf;
83 	struct otx_ep_instr_queue *iq;
84 	struct otx_ep_sg_entry *sg;
85 	uint32_t i, q_size;
86 	int ret;
87 
88 	conf = otx_ep->conf;
89 	iq = otx_ep->instr_queue[iq_no];
90 	q_size = conf->iq.instr_type * num_descs;
91 
92 	/* IQ memory creation for Instruction submission to OCTEON 9 */
93 	iq->iq_mz = rte_eth_dma_zone_reserve(otx_ep->eth_dev,
94 					     "instr_queue", iq_no, q_size,
95 					     OTX_EP_PCI_RING_ALIGN,
96 					     socket_id);
97 	if (iq->iq_mz == NULL) {
98 		otx_ep_err("IQ[%d] memzone alloc failed\n", iq_no);
99 		goto iq_init_fail;
100 	}
101 
102 	iq->base_addr_dma = iq->iq_mz->iova;
103 	iq->base_addr = (uint8_t *)iq->iq_mz->addr;
104 
105 	if (num_descs & (num_descs - 1)) {
106 		otx_ep_err("IQ[%d] descs not in power of 2\n", iq_no);
107 		goto iq_init_fail;
108 	}
109 
110 	iq->nb_desc = num_descs;
111 
112 	/* Create a IQ request list to hold requests that have been
113 	 * posted to OCTEON 9. This list will be used for freeing the IQ
114 	 * data buffer(s) later once the OCTEON 9 fetched the requests.
115 	 */
116 	iq->req_list = rte_zmalloc_socket("request_list",
117 			(iq->nb_desc * OTX_EP_IQREQ_LIST_SIZE),
118 			RTE_CACHE_LINE_SIZE,
119 			rte_socket_id());
120 	if (iq->req_list == NULL) {
121 		otx_ep_err("IQ[%d] req_list alloc failed\n", iq_no);
122 		goto iq_init_fail;
123 	}
124 
125 	for (i = 0; i < iq->nb_desc; i++) {
126 		sg = rte_zmalloc_socket("sg_entry", (OTX_EP_MAX_SG_LISTS * OTX_EP_SG_ENTRY_SIZE),
127 			OTX_EP_SG_ALIGN, rte_socket_id());
128 		if (sg == NULL) {
129 			otx_ep_err("IQ[%d] sg_entries alloc failed\n", iq_no);
130 			goto iq_init_fail;
131 		}
132 
133 		iq->req_list[i].finfo.g.num_sg = OTX_EP_MAX_SG_LISTS;
134 		iq->req_list[i].finfo.g.sg = sg;
135 	}
136 
137 	otx_ep_info("IQ[%d]: base: %p basedma: %lx count: %d\n",
138 		     iq_no, iq->base_addr, (unsigned long)iq->base_addr_dma,
139 		     iq->nb_desc);
140 
141 	iq->mbuf_list = rte_zmalloc_socket("mbuf_list",	(iq->nb_desc * sizeof(struct rte_mbuf *)),
142 					   RTE_CACHE_LINE_SIZE, rte_socket_id());
143 	if (!iq->mbuf_list) {
144 		otx_ep_err("IQ[%d] mbuf_list alloc failed\n", iq_no);
145 		goto iq_init_fail;
146 	}
147 
148 	iq->otx_ep_dev = otx_ep;
149 	iq->q_no = iq_no;
150 	iq->fill_cnt = 0;
151 	iq->host_write_index = 0;
152 	iq->otx_read_index = 0;
153 	iq->flush_index = 0;
154 	iq->instr_pending = 0;
155 
156 	otx_ep->io_qmask.iq |= (1ull << iq_no);
157 
158 	/* Set 32B/64B mode for each input queue */
159 	if (conf->iq.instr_type == 64)
160 		otx_ep->io_qmask.iq64B |= (1ull << iq_no);
161 
162 	iq->iqcmd_64B = (conf->iq.instr_type == 64);
163 	iq->ism_ena = otx_ep->ism_ena;
164 
165 	/* Set up IQ registers */
166 	ret = otx_ep->fn_list.setup_iq_regs(otx_ep, iq_no);
167 	if (ret)
168 		return ret;
169 
170 	return 0;
171 
172 iq_init_fail:
173 	return -ENOMEM;
174 }
175 
176 int
177 otx_ep_setup_iqs(struct otx_ep_device *otx_ep, uint32_t iq_no, int num_descs,
178 		 unsigned int socket_id)
179 {
180 	struct otx_ep_instr_queue *iq;
181 
182 	iq = (struct otx_ep_instr_queue *)rte_zmalloc("otx_ep_IQ", sizeof(*iq),
183 						RTE_CACHE_LINE_SIZE);
184 	if (iq == NULL)
185 		return -ENOMEM;
186 
187 	otx_ep->instr_queue[iq_no] = iq;
188 
189 	if (otx_ep_init_instr_queue(otx_ep, iq_no, num_descs, socket_id)) {
190 		otx_ep_err("IQ init is failed\n");
191 		goto delete_IQ;
192 	}
193 	otx_ep->nb_tx_queues++;
194 
195 	otx_ep_info("IQ[%d] is created.\n", iq_no);
196 
197 	return 0;
198 
199 delete_IQ:
200 	otx_ep_delete_iqs(otx_ep, iq_no);
201 	return -ENOMEM;
202 }
203 
204 static void
205 otx_ep_droq_reset_indices(struct otx_ep_droq *droq)
206 {
207 	droq->read_idx  = 0;
208 	droq->write_idx = 0;
209 	droq->refill_idx = 0;
210 	droq->refill_count = 0;
211 	droq->last_pkt_count = 0;
212 	droq->pkts_pending = 0;
213 }
214 
215 static void
216 otx_ep_droq_destroy_ring_buffers(struct otx_ep_droq *droq)
217 {
218 	uint32_t idx;
219 
220 	for (idx = 0; idx < droq->nb_desc; idx++) {
221 		if (droq->recv_buf_list[idx]) {
222 			rte_pktmbuf_free(droq->recv_buf_list[idx]);
223 			droq->recv_buf_list[idx] = NULL;
224 		}
225 	}
226 
227 	otx_ep_droq_reset_indices(droq);
228 }
229 
230 /* Free OQs resources */
231 int
232 otx_ep_delete_oqs(struct otx_ep_device *otx_ep, uint32_t oq_no)
233 {
234 	struct otx_ep_droq *droq;
235 
236 	droq = otx_ep->droq[oq_no];
237 	if (droq == NULL) {
238 		otx_ep_err("Invalid droq[%d]\n", oq_no);
239 		return -EINVAL;
240 	}
241 
242 	otx_ep_droq_destroy_ring_buffers(droq);
243 	rte_free(droq->recv_buf_list);
244 	droq->recv_buf_list = NULL;
245 
246 	if (droq->desc_ring_mz) {
247 		otx_ep_dmazone_free(droq->desc_ring_mz);
248 		droq->desc_ring_mz = NULL;
249 	}
250 
251 	memset(droq, 0, OTX_EP_DROQ_SIZE);
252 
253 	rte_free(otx_ep->droq[oq_no]);
254 	otx_ep->droq[oq_no] = NULL;
255 
256 	otx_ep->nb_rx_queues--;
257 
258 	otx_ep_info("OQ[%d] is deleted\n", oq_no);
259 	return 0;
260 }
261 
262 static int
263 otx_ep_droq_setup_ring_buffers(struct otx_ep_droq *droq)
264 {
265 	struct otx_ep_droq_desc *desc_ring = droq->desc_ring;
266 	struct otx_ep_droq_info *info;
267 	struct rte_mbuf *buf;
268 	uint32_t idx;
269 
270 	for (idx = 0; idx < droq->nb_desc; idx++) {
271 		buf = rte_pktmbuf_alloc(droq->mpool);
272 		if (buf == NULL) {
273 			otx_ep_err("OQ buffer alloc failed\n");
274 			droq->stats.rx_alloc_failure++;
275 			return -ENOMEM;
276 		}
277 
278 		droq->recv_buf_list[idx] = buf;
279 		info = rte_pktmbuf_mtod(buf, struct otx_ep_droq_info *);
280 		memset(info, 0, sizeof(*info));
281 		desc_ring[idx].buffer_ptr = rte_mbuf_data_iova_default(buf);
282 	}
283 
284 	otx_ep_droq_reset_indices(droq);
285 
286 	return 0;
287 }
288 
289 static inline uint64_t
290 otx_ep_set_rearm_data(struct otx_ep_device *otx_ep)
291 {
292 	uint16_t port_id = otx_ep->port_id;
293 	struct rte_mbuf mb_def;
294 	uint64_t *tmp;
295 
296 	RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, data_off) % 8 != 0);
297 	RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, refcnt) - offsetof(struct rte_mbuf, data_off) !=
298 			 2);
299 	RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, nb_segs) - offsetof(struct rte_mbuf, data_off) !=
300 			 4);
301 	RTE_BUILD_BUG_ON(offsetof(struct rte_mbuf, port) - offsetof(struct rte_mbuf, data_off) !=
302 			 6);
303 	mb_def.nb_segs = 1;
304 	mb_def.data_off = RTE_PKTMBUF_HEADROOM + OTX_EP_INFO_SIZE;
305 	mb_def.port = port_id;
306 	rte_mbuf_refcnt_set(&mb_def, 1);
307 
308 	/* Prevent compiler reordering: rearm_data covers previous fields */
309 	rte_compiler_barrier();
310 	tmp = (uint64_t *)&mb_def.rearm_data;
311 
312 	return *tmp;
313 }
314 
315 /* OQ initialization */
316 static int
317 otx_ep_init_droq(struct otx_ep_device *otx_ep, uint32_t q_no,
318 	      uint32_t num_descs, uint32_t desc_size,
319 	      struct rte_mempool *mpool, unsigned int socket_id)
320 {
321 	const struct otx_ep_config *conf = otx_ep->conf;
322 	uint32_t c_refill_threshold;
323 	struct otx_ep_droq *droq;
324 	uint32_t desc_ring_size;
325 	int ret;
326 
327 	otx_ep_info("OQ[%d] Init start\n", q_no);
328 
329 	droq = otx_ep->droq[q_no];
330 	droq->otx_ep_dev = otx_ep;
331 	droq->q_no = q_no;
332 	droq->mpool = mpool;
333 
334 	droq->nb_desc      = num_descs;
335 	droq->buffer_size  = desc_size;
336 	c_refill_threshold = RTE_MAX(conf->oq.refill_threshold,
337 				     droq->nb_desc / 2);
338 
339 	/* OQ desc_ring set up */
340 	desc_ring_size = droq->nb_desc * OTX_EP_DROQ_DESC_SIZE;
341 	droq->desc_ring_mz = rte_eth_dma_zone_reserve(otx_ep->eth_dev, "droq",
342 						      q_no, desc_ring_size,
343 						      OTX_EP_PCI_RING_ALIGN,
344 						      socket_id);
345 
346 	if (droq->desc_ring_mz == NULL) {
347 		otx_ep_err("OQ:%d desc_ring allocation failed\n", q_no);
348 		goto init_droq_fail;
349 	}
350 
351 	droq->desc_ring_dma = droq->desc_ring_mz->iova;
352 	droq->desc_ring = (struct otx_ep_droq_desc *)droq->desc_ring_mz->addr;
353 
354 	otx_ep_dbg("OQ[%d]: desc_ring: virt: 0x%p, dma: %lx\n",
355 		    q_no, droq->desc_ring, (unsigned long)droq->desc_ring_dma);
356 	otx_ep_dbg("OQ[%d]: num_desc: %d\n", q_no, droq->nb_desc);
357 
358 	/* OQ buf_list set up */
359 	droq->recv_buf_list = rte_zmalloc_socket("recv_buf_list",
360 				(droq->nb_desc * sizeof(struct rte_mbuf *)),
361 				 RTE_CACHE_LINE_SIZE, socket_id);
362 	if (droq->recv_buf_list == NULL) {
363 		otx_ep_err("OQ recv_buf_list alloc failed\n");
364 		goto init_droq_fail;
365 	}
366 
367 	if (otx_ep_droq_setup_ring_buffers(droq))
368 		goto init_droq_fail;
369 
370 	droq->refill_threshold = c_refill_threshold;
371 	droq->rearm_data = otx_ep_set_rearm_data(otx_ep);
372 	droq->ism_ena = otx_ep->ism_ena;
373 
374 	/* Set up OQ registers */
375 	ret = otx_ep->fn_list.setup_oq_regs(otx_ep, q_no);
376 	if (ret)
377 		return ret;
378 
379 	otx_ep->io_qmask.oq |= (1ull << q_no);
380 
381 	return 0;
382 
383 init_droq_fail:
384 	return -ENOMEM;
385 }
386 
387 /* OQ configuration and setup */
388 int
389 otx_ep_setup_oqs(struct otx_ep_device *otx_ep, int oq_no, int num_descs,
390 		 int desc_size, struct rte_mempool *mpool,
391 		 unsigned int socket_id)
392 {
393 	struct otx_ep_droq *droq;
394 
395 	/* Allocate new droq. */
396 	droq = (struct otx_ep_droq *)rte_zmalloc("otx_ep_OQ",
397 				sizeof(*droq), RTE_CACHE_LINE_SIZE);
398 	if (droq == NULL) {
399 		otx_ep_err("Droq[%d] Creation Failed\n", oq_no);
400 		return -ENOMEM;
401 	}
402 	otx_ep->droq[oq_no] = droq;
403 
404 	if (otx_ep_init_droq(otx_ep, oq_no, num_descs, desc_size, mpool,
405 			     socket_id)) {
406 		otx_ep_err("Droq[%d] Initialization failed\n", oq_no);
407 		goto delete_OQ;
408 	}
409 	otx_ep_info("OQ[%d] is created.\n", oq_no);
410 
411 	otx_ep->nb_rx_queues++;
412 
413 	return 0;
414 
415 delete_OQ:
416 	otx_ep_delete_oqs(otx_ep, oq_no);
417 	return -ENOMEM;
418 }
419 
420 static inline void
421 otx_ep_iqreq_delete(struct otx_ep_instr_queue *iq, uint32_t idx)
422 {
423 	struct rte_mbuf *mbuf;
424 	uint32_t reqtype;
425 
426 	mbuf    = iq->req_list[idx].finfo.mbuf;
427 	reqtype = iq->req_list[idx].reqtype;
428 
429 	switch (reqtype) {
430 	case OTX_EP_REQTYPE_NORESP_NET:
431 	case OTX_EP_REQTYPE_NORESP_GATHER:
432 		/* This will take care of multiple segments also */
433 		rte_pktmbuf_free(mbuf);
434 		otx_ep_dbg("IQ buffer freed at idx[%d]\n", idx);
435 		break;
436 
437 	case OTX_EP_REQTYPE_NONE:
438 	default:
439 		otx_ep_info("This iqreq mode is not supported:%d\n", reqtype);
440 	}
441 
442 	/* Reset the request list at this index */
443 	iq->req_list[idx].finfo.mbuf = NULL;
444 	iq->req_list[idx].reqtype = 0;
445 }
446 
447 static inline void
448 otx_ep_iqreq_add(struct otx_ep_instr_queue *iq, struct rte_mbuf *mbuf,
449 		uint32_t reqtype, int index)
450 {
451 	iq->req_list[index].finfo.mbuf = mbuf;
452 	iq->req_list[index].reqtype = reqtype;
453 }
454 
455 static uint32_t
456 otx_vf_update_read_index(struct otx_ep_instr_queue *iq)
457 {
458 	uint32_t val;
459 
460 	/*
461 	 * Batch subtractions from the HW counter to reduce PCIe traffic
462 	 * This adds an extra local variable, but almost halves the
463 	 * number of PCIe writes.
464 	 */
465 	val = *iq->inst_cnt_ism;
466 	iq->inst_cnt += val - iq->inst_cnt_prev;
467 	iq->inst_cnt_prev = val;
468 
469 	if (val > (uint32_t)(1 << 31)) {
470 		/*
471 		 * Only subtract the packet count in the HW counter
472 		 * when count above halfway to saturation.
473 		 */
474 		rte_write32(val, iq->inst_cnt_reg);
475 		rte_mb();
476 
477 		rte_write64(OTX2_SDP_REQUEST_ISM, iq->inst_cnt_reg);
478 		while (__atomic_load_n(iq->inst_cnt_ism, __ATOMIC_RELAXED) >= val) {
479 			rte_write64(OTX2_SDP_REQUEST_ISM, iq->inst_cnt_reg);
480 			rte_mb();
481 		}
482 
483 		iq->inst_cnt_prev = 0;
484 	}
485 	rte_write64(OTX2_SDP_REQUEST_ISM, iq->inst_cnt_reg);
486 
487 	/* Modulo of the new index with the IQ size will give us
488 	 * the new index.
489 	 */
490 	return iq->inst_cnt & (iq->nb_desc - 1);
491 }
492 
493 static void
494 otx_ep_flush_iq(struct otx_ep_instr_queue *iq)
495 {
496 	uint32_t instr_processed = 0;
497 
498 	iq->otx_read_index = otx_vf_update_read_index(iq);
499 	while (iq->flush_index != iq->otx_read_index) {
500 		/* Free the IQ data buffer to the pool */
501 		otx_ep_iqreq_delete(iq, iq->flush_index);
502 		iq->flush_index =
503 			otx_ep_incr_index(iq->flush_index, 1, iq->nb_desc);
504 
505 		instr_processed++;
506 	}
507 
508 	iq->stats.instr_processed = instr_processed;
509 	iq->instr_pending -= instr_processed;
510 }
511 
512 static inline void
513 otx_ep_ring_doorbell(struct otx_ep_device *otx_ep __rte_unused,
514 		struct otx_ep_instr_queue *iq)
515 {
516 	rte_wmb();
517 	rte_write64(iq->fill_cnt, iq->doorbell_reg);
518 	iq->fill_cnt = 0;
519 }
520 
521 static inline int
522 post_iqcmd(struct otx_ep_instr_queue *iq, uint8_t *iqcmd)
523 {
524 	uint8_t *iqptr, cmdsize;
525 
526 	/* This ensures that the read index does not wrap around to
527 	 * the same position if queue gets full before OCTEON 9 could
528 	 * fetch any instr.
529 	 */
530 	if (iq->instr_pending > (iq->nb_desc - 1))
531 		return OTX_EP_IQ_SEND_FAILED;
532 
533 	/* Copy cmd into iq */
534 	cmdsize = 64;
535 	iqptr   = iq->base_addr + (iq->host_write_index << 6);
536 
537 	rte_memcpy(iqptr, iqcmd, cmdsize);
538 
539 	/* Increment the host write index */
540 	iq->host_write_index =
541 		otx_ep_incr_index(iq->host_write_index, 1, iq->nb_desc);
542 
543 	iq->fill_cnt++;
544 
545 	/* Flush the command into memory. We need to be sure the data
546 	 * is in memory before indicating that the instruction is
547 	 * pending.
548 	 */
549 	iq->instr_pending++;
550 	/* OTX_EP_IQ_SEND_SUCCESS */
551 	return 0;
552 }
553 
554 
555 static int
556 otx_ep_send_data(struct otx_ep_device *otx_ep, struct otx_ep_instr_queue *iq,
557 		 void *cmd, int dbell)
558 {
559 	uint32_t ret;
560 
561 	/* Submit IQ command */
562 	ret = post_iqcmd(iq, cmd);
563 
564 	if (ret == OTX_EP_IQ_SEND_SUCCESS) {
565 		if (dbell)
566 			otx_ep_ring_doorbell(otx_ep, iq);
567 		iq->stats.instr_posted++;
568 
569 	} else {
570 		iq->stats.instr_dropped++;
571 		if (iq->fill_cnt)
572 			otx_ep_ring_doorbell(otx_ep, iq);
573 	}
574 	return ret;
575 }
576 
577 static inline void
578 set_sg_size(struct otx_ep_sg_entry *sg_entry, uint16_t size, uint32_t pos)
579 {
580 #if RTE_BYTE_ORDER == RTE_BIG_ENDIAN
581 	sg_entry->u.size[pos] = size;
582 #elif RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
583 	sg_entry->u.size[(OTX_EP_NUM_SG_PTRS - 1) - pos] = size;
584 #endif
585 }
586 
587 static inline int
588 prepare_xmit_gather_list(struct otx_ep_instr_queue *iq, struct rte_mbuf *m, uint64_t *dptr,
589 			 union otx_ep_instr_ih *ih)
590 {
591 	uint16_t j = 0, frags, num_sg, mask = OTX_EP_NUM_SG_PTRS - 1;
592 	struct otx_ep_buf_free_info *finfo;
593 	uint32_t pkt_len;
594 	int rc = -1;
595 
596 	pkt_len = rte_pktmbuf_pkt_len(m);
597 	frags = m->nb_segs;
598 	num_sg = (frags + mask) / OTX_EP_NUM_SG_PTRS;
599 
600 	if (unlikely(pkt_len > OTX_EP_MAX_PKT_SZ && num_sg > OTX_EP_MAX_SG_LISTS)) {
601 		otx_ep_err("Failed to xmit the pkt, pkt_len is higher or pkt has more segments\n");
602 		goto exit;
603 	}
604 
605 	finfo = &iq->req_list[iq->host_write_index].finfo;
606 	*dptr = rte_mem_virt2iova(finfo->g.sg);
607 	ih->u64 |= ((1ULL << 62) | ((uint64_t)frags << 48) | (pkt_len + ih->s.fsz));
608 
609 	while (frags--) {
610 		finfo->g.sg[(j >> 2)].ptr[(j & mask)] = rte_mbuf_data_iova(m);
611 		set_sg_size(&finfo->g.sg[(j >> 2)], m->data_len, (j & mask));
612 		j++;
613 		m = m->next;
614 	}
615 
616 	return 0;
617 
618 exit:
619 	return rc;
620 }
621 
622 /* Enqueue requests/packets to OTX_EP IQ queue.
623  * returns number of requests enqueued successfully
624  */
625 uint16_t
626 otx_ep_xmit_pkts(void *tx_queue, struct rte_mbuf **pkts, uint16_t nb_pkts)
627 {
628 	struct otx_ep_instr_queue *iq = (struct otx_ep_instr_queue *)tx_queue;
629 	struct otx_ep_device *otx_ep = iq->otx_ep_dev;
630 	struct otx_ep_instr_64B iqcmd;
631 	int dbell, index, count = 0;
632 	uint32_t iqreq_type;
633 	uint32_t pkt_len, i;
634 	struct rte_mbuf *m;
635 
636 	iqcmd.ih.u64 = 0;
637 	iqcmd.pki_ih3.u64 = 0;
638 	iqcmd.irh.u64 = 0;
639 
640 	/* ih invars */
641 	iqcmd.ih.s.fsz = OTX_EP_FSZ;
642 	iqcmd.ih.s.pkind = otx_ep->pkind; /* The SDK decided PKIND value */
643 
644 	/* pki ih3 invars */
645 	iqcmd.pki_ih3.s.w = 1;
646 	iqcmd.pki_ih3.s.utt = 1;
647 	iqcmd.pki_ih3.s.tagtype = ORDERED_TAG;
648 	/* sl will be sizeof(pki_ih3) */
649 	iqcmd.pki_ih3.s.sl = OTX_EP_FSZ + OTX_CUST_DATA_LEN;
650 
651 	/* irh invars */
652 	iqcmd.irh.s.opcode = OTX_EP_NW_PKT_OP;
653 
654 	for (i = 0; i < nb_pkts; i++) {
655 		m = pkts[i];
656 		if (m->nb_segs == 1) {
657 			pkt_len = rte_pktmbuf_data_len(m);
658 			iqcmd.ih.s.tlen = pkt_len + iqcmd.ih.s.fsz;
659 			iqcmd.dptr = rte_mbuf_data_iova(m); /*dptr*/
660 			iqcmd.ih.s.gather = 0;
661 			iqcmd.ih.s.gsz = 0;
662 			iqreq_type = OTX_EP_REQTYPE_NORESP_NET;
663 		} else {
664 			if (!(otx_ep->tx_offloads & RTE_ETH_TX_OFFLOAD_MULTI_SEGS))
665 				goto xmit_fail;
666 
667 			if (unlikely(prepare_xmit_gather_list(iq, m, &iqcmd.dptr, &iqcmd.ih) < 0))
668 				goto xmit_fail;
669 
670 			pkt_len = rte_pktmbuf_pkt_len(m);
671 			iqreq_type = OTX_EP_REQTYPE_NORESP_GATHER;
672 		}
673 
674 		iqcmd.irh.u64 = rte_bswap64(iqcmd.irh.u64);
675 
676 #ifdef OTX_EP_IO_DEBUG
677 		otx_ep_dbg("After swapping\n");
678 		otx_ep_dbg("Word0 [dptr]: 0x%016lx\n",
679 			   (unsigned long)iqcmd.dptr);
680 		otx_ep_dbg("Word1 [ihtx]: 0x%016lx\n", (unsigned long)iqcmd.ih);
681 		otx_ep_dbg("Word2 [pki_ih3]: 0x%016lx\n",
682 			   (unsigned long)iqcmd.pki_ih3);
683 		otx_ep_dbg("Word3 [rptr]: 0x%016lx\n",
684 			   (unsigned long)iqcmd.rptr);
685 		otx_ep_dbg("Word4 [irh]: 0x%016lx\n", (unsigned long)iqcmd.irh);
686 		otx_ep_dbg("Word5 [exhdr[0]]: 0x%016lx\n",
687 				(unsigned long)iqcmd.exhdr[0]);
688 		rte_pktmbuf_dump(stdout, m, rte_pktmbuf_pkt_len(m));
689 #endif
690 		dbell = (i == (unsigned int)(nb_pkts - 1)) ? 1 : 0;
691 		index = iq->host_write_index;
692 		if (otx_ep_send_data(otx_ep, iq, &iqcmd, dbell))
693 			goto xmit_fail;
694 		otx_ep_iqreq_add(iq, m, iqreq_type, index);
695 		iq->stats.tx_pkts++;
696 		iq->stats.tx_bytes += pkt_len;
697 		count++;
698 	}
699 
700 xmit_fail:
701 	if (iq->instr_pending >= OTX_EP_MAX_INSTR)
702 		otx_ep_flush_iq(iq);
703 
704 	/* Return no# of instructions posted successfully. */
705 	return count;
706 }
707 
708 static uint32_t
709 otx_ep_droq_refill(struct otx_ep_droq *droq)
710 {
711 	struct otx_ep_droq_desc *desc_ring = droq->desc_ring;
712 	struct otx_ep_droq_info *info;
713 	struct rte_mbuf *buf = NULL;
714 	uint32_t desc_refilled = 0;
715 
716 	while (droq->refill_count && (desc_refilled < droq->nb_desc)) {
717 		buf = rte_pktmbuf_alloc(droq->mpool);
718 		/* If a buffer could not be allocated, no point in
719 		 * continuing
720 		 */
721 		if (unlikely(!buf)) {
722 			droq->stats.rx_alloc_failure++;
723 			break;
724 		}
725 		info = rte_pktmbuf_mtod(buf, struct otx_ep_droq_info *);
726 		info->length = 0;
727 
728 		droq->recv_buf_list[droq->refill_idx] = buf;
729 		desc_ring[droq->refill_idx].buffer_ptr =
730 					rte_mbuf_data_iova_default(buf);
731 		droq->refill_idx = otx_ep_incr_index(droq->refill_idx, 1,
732 				droq->nb_desc);
733 
734 		desc_refilled++;
735 		droq->refill_count--;
736 	}
737 
738 	return desc_refilled;
739 }
740 
741 static struct rte_mbuf *
742 otx_ep_droq_read_packet(struct otx_ep_device *otx_ep, struct otx_ep_droq *droq, int next_fetch)
743 {
744 	volatile struct otx_ep_droq_info *info;
745 	struct rte_mbuf *mbuf_next = NULL;
746 	struct rte_mbuf *mbuf = NULL;
747 	uint64_t total_pkt_len;
748 	uint32_t pkt_len = 0;
749 	int next_idx;
750 
751 	mbuf = droq->recv_buf_list[droq->read_idx];
752 	info = rte_pktmbuf_mtod(mbuf, struct otx_ep_droq_info *);
753 
754 	/* make sure info is available */
755 	rte_rmb();
756 	if (unlikely(!info->length)) {
757 		int retry = OTX_EP_MAX_DELAYED_PKT_RETRIES;
758 		/* otx_ep_dbg("OCTEON DROQ[%d]: read_idx: %d; Data not ready "
759 		 * "yet, Retry; pending=%lu\n", droq->q_no, droq->read_idx,
760 		 * droq->pkts_pending);
761 		 */
762 		droq->stats.pkts_delayed_data++;
763 		while (retry && !info->length) {
764 			retry--;
765 			rte_delay_us_block(50);
766 		}
767 		if (!retry && !info->length) {
768 			otx_ep_err("OCTEON DROQ[%d]: read_idx: %d; Retry failed !!\n",
769 				   droq->q_no, droq->read_idx);
770 			/* May be zero length packet; drop it */
771 			assert(0);
772 		}
773 	}
774 
775 	if (next_fetch) {
776 		next_idx = otx_ep_incr_index(droq->read_idx, 1, droq->nb_desc);
777 		mbuf_next = droq->recv_buf_list[next_idx];
778 		rte_prefetch0(rte_pktmbuf_mtod(mbuf_next, void *));
779 	}
780 
781 	info->length = rte_bswap16(info->length >> 48);
782 	/* Deduce the actual data size */
783 	total_pkt_len = info->length + OTX_EP_INFO_SIZE;
784 	if (total_pkt_len <= droq->buffer_size) {
785 		mbuf->data_off += OTX_EP_INFO_SIZE;
786 		pkt_len = (uint32_t)info->length;
787 		mbuf->pkt_len  = pkt_len;
788 		mbuf->data_len  = pkt_len;
789 		mbuf->port = otx_ep->port_id;
790 		droq->recv_buf_list[droq->read_idx] = NULL;
791 		droq->read_idx = otx_ep_incr_index(droq->read_idx, 1, droq->nb_desc);
792 		droq->refill_count++;
793 	} else {
794 		struct rte_mbuf *first_buf = NULL;
795 		struct rte_mbuf *last_buf = NULL;
796 
797 		/* csr read helps to flush pending dma */
798 		droq->sent_reg_val = rte_read32(droq->pkts_sent_reg);
799 		rte_rmb();
800 
801 		while (pkt_len < total_pkt_len) {
802 			int cpy_len = 0;
803 
804 			cpy_len = ((pkt_len + droq->buffer_size) > total_pkt_len)
805 					? ((uint32_t)total_pkt_len - pkt_len)
806 					: droq->buffer_size;
807 
808 			mbuf = droq->recv_buf_list[droq->read_idx];
809 			droq->recv_buf_list[droq->read_idx] = NULL;
810 
811 			if (likely(mbuf)) {
812 				/* Note the first seg */
813 				if (!pkt_len)
814 					first_buf = mbuf;
815 
816 				mbuf->port = otx_ep->port_id;
817 				if (!pkt_len) {
818 					mbuf->data_off += OTX_EP_INFO_SIZE;
819 					mbuf->pkt_len = cpy_len - OTX_EP_INFO_SIZE;
820 					mbuf->data_len = cpy_len - OTX_EP_INFO_SIZE;
821 				} else {
822 					mbuf->pkt_len = cpy_len;
823 					mbuf->data_len = cpy_len;
824 				}
825 
826 				if (pkt_len) {
827 					first_buf->nb_segs++;
828 					first_buf->pkt_len += mbuf->pkt_len;
829 				}
830 
831 				if (last_buf)
832 					last_buf->next = mbuf;
833 
834 				last_buf = mbuf;
835 			} else {
836 				otx_ep_err("no buf\n");
837 				assert(0);
838 			}
839 
840 			pkt_len += cpy_len;
841 			droq->read_idx = otx_ep_incr_index(droq->read_idx, 1, droq->nb_desc);
842 			droq->refill_count++;
843 		}
844 		mbuf = first_buf;
845 	}
846 
847 	return mbuf;
848 }
849 
850 static inline uint32_t
851 otx_ep_check_droq_pkts(struct otx_ep_droq *droq)
852 {
853 	uint32_t new_pkts;
854 	uint32_t val;
855 
856 	/*
857 	 * Batch subtractions from the HW counter to reduce PCIe traffic
858 	 * This adds an extra local variable, but almost halves the
859 	 * number of PCIe writes.
860 	 */
861 	val = *droq->pkts_sent_ism;
862 	new_pkts = val - droq->pkts_sent_prev;
863 	droq->pkts_sent_prev = val;
864 
865 	if (val > (uint32_t)(1 << 31)) {
866 		/*
867 		 * Only subtract the packet count in the HW counter
868 		 * when count above halfway to saturation.
869 		 */
870 		rte_write32(val, droq->pkts_sent_reg);
871 		rte_mb();
872 
873 		rte_write64(OTX2_SDP_REQUEST_ISM, droq->pkts_sent_reg);
874 		while (__atomic_load_n(droq->pkts_sent_ism, __ATOMIC_RELAXED) >= val) {
875 			rte_write64(OTX2_SDP_REQUEST_ISM, droq->pkts_sent_reg);
876 			rte_mb();
877 		}
878 
879 		droq->pkts_sent_prev = 0;
880 	}
881 	rte_write64(OTX2_SDP_REQUEST_ISM, droq->pkts_sent_reg);
882 	droq->pkts_pending += new_pkts;
883 
884 	return new_pkts;
885 }
886 
887 static inline int32_t __rte_hot
888 otx_ep_rx_pkts_to_process(struct otx_ep_droq *droq, uint16_t nb_pkts)
889 {
890 	if (unlikely(droq->pkts_pending < nb_pkts))
891 		otx_ep_check_droq_pkts(droq);
892 
893 	return RTE_MIN(nb_pkts, droq->pkts_pending);
894 }
895 
896 /* Check for response arrival from OCTEON 9
897  * returns number of requests completed
898  */
899 uint16_t
900 otx_ep_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
901 {
902 	struct otx_ep_droq *droq = rx_queue;
903 	struct otx_ep_device *otx_ep;
904 	struct rte_mbuf *oq_pkt;
905 	uint16_t pkts, new_pkts;
906 	uint32_t valid_pkts = 0;
907 	int next_fetch;
908 
909 	otx_ep = droq->otx_ep_dev;
910 	new_pkts = otx_ep_rx_pkts_to_process(droq, nb_pkts);
911 
912 	for (pkts = 0; pkts < new_pkts; pkts++) {
913 		/* Push the received pkt to application */
914 		next_fetch = (pkts == new_pkts - 1) ? 0 : 1;
915 		oq_pkt = otx_ep_droq_read_packet(otx_ep, droq, next_fetch);
916 		if (!oq_pkt) {
917 			RTE_LOG_DP(ERR, OTX_NET_EP,
918 				   "DROQ read pkt failed pending %" PRIu64
919 				    "last_pkt_count %" PRIu64 "new_pkts %d.\n",
920 				   droq->pkts_pending, droq->last_pkt_count,
921 				   new_pkts);
922 			droq->stats.rx_err++;
923 			continue;
924 		} else {
925 			rx_pkts[valid_pkts] = oq_pkt;
926 			valid_pkts++;
927 			/* Stats */
928 			droq->stats.pkts_received++;
929 			droq->stats.bytes_received += oq_pkt->pkt_len;
930 		}
931 	}
932 	droq->pkts_pending -= pkts;
933 
934 	/* Refill DROQ buffers */
935 	if (droq->refill_count >= DROQ_REFILL_THRESHOLD) {
936 		int desc_refilled = otx_ep_droq_refill(droq);
937 
938 		/* Flush the droq descriptor data to memory to be sure
939 		 * that when we update the credits the data in memory is
940 		 * accurate.
941 		 */
942 		rte_io_wmb();
943 		rte_write32(desc_refilled, droq->pkts_credit_reg);
944 	} else {
945 		/*
946 		 * SDP output goes into DROP state when output doorbell count
947 		 * goes below drop count. When door bell count is written with
948 		 * a value greater than drop count SDP output should come out
949 		 * of DROP state. Due to a race condition this is not happening.
950 		 * Writing doorbell register with 0 again may make SDP output
951 		 * come out of this state.
952 		 */
953 
954 		rte_write32(0, droq->pkts_credit_reg);
955 	}
956 	return valid_pkts;
957 }
958