xref: /dpdk/drivers/net/mlx5/mlx5_txpp.c (revision ac3fc732c42c77d2553c136085e64b6c0ce6bd0e)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright 2020 Mellanox Technologies, Ltd
3  */
4 #include <fcntl.h>
5 #include <stdint.h>
6 
7 #include <rte_ether.h>
8 #include <rte_ethdev_driver.h>
9 #include <rte_interrupts.h>
10 #include <rte_alarm.h>
11 #include <rte_malloc.h>
12 #include <rte_cycles.h>
13 
14 #include <mlx5_malloc.h>
15 
16 #include "mlx5.h"
17 #include "mlx5_rxtx.h"
18 #include "mlx5_common_os.h"
19 
20 static const char * const mlx5_txpp_stat_names[] = {
21 	"txpp_err_miss_int", /* Missed service interrupt. */
22 	"txpp_err_rearm_queue",	/* Rearm Queue errors. */
23 	"txpp_err_clock_queue", /* Clock Queue errors. */
24 	"txpp_err_ts_past", /* Timestamp in the past. */
25 	"txpp_err_ts_future", /* Timestamp in the distant future. */
26 	"txpp_jitter", /* Timestamp jitter (one Clock Queue completion). */
27 	"txpp_wander", /* Timestamp jitter (half of Clock Queue completions). */
28 	"txpp_sync_lost", /* Scheduling synchronization lost. */
29 };
30 
31 /* Destroy Event Queue Notification Channel. */
32 static void
33 mlx5_txpp_destroy_eqn(struct mlx5_dev_ctx_shared *sh)
34 {
35 	if (sh->txpp.echan) {
36 		mlx5_glue->devx_destroy_event_channel(sh->txpp.echan);
37 		sh->txpp.echan = NULL;
38 	}
39 	sh->txpp.eqn = 0;
40 }
41 
42 /* Create Event Queue Notification Channel. */
43 static int
44 mlx5_txpp_create_eqn(struct mlx5_dev_ctx_shared *sh)
45 {
46 	uint32_t lcore;
47 
48 	MLX5_ASSERT(!sh->txpp.echan);
49 	lcore = (uint32_t)rte_lcore_to_cpu_id(-1);
50 	if (mlx5_glue->devx_query_eqn(sh->ctx, lcore, &sh->txpp.eqn)) {
51 		rte_errno = errno;
52 		DRV_LOG(ERR, "Failed to query EQ number %d.", rte_errno);
53 		sh->txpp.eqn = 0;
54 		return -rte_errno;
55 	}
56 	sh->txpp.echan = mlx5_glue->devx_create_event_channel(sh->ctx,
57 			MLX5DV_DEVX_CREATE_EVENT_CHANNEL_FLAGS_OMIT_EV_DATA);
58 	if (!sh->txpp.echan) {
59 		sh->txpp.eqn = 0;
60 		rte_errno = errno;
61 		DRV_LOG(ERR, "Failed to create event channel %d.",
62 			rte_errno);
63 		return -rte_errno;
64 	}
65 	return 0;
66 }
67 
68 static void
69 mlx5_txpp_free_pp_index(struct mlx5_dev_ctx_shared *sh)
70 {
71 	if (sh->txpp.pp) {
72 		mlx5_glue->dv_free_pp(sh->txpp.pp);
73 		sh->txpp.pp = NULL;
74 		sh->txpp.pp_id = 0;
75 	}
76 }
77 
78 /* Allocate Packet Pacing index from kernel via mlx5dv call. */
79 static int
80 mlx5_txpp_alloc_pp_index(struct mlx5_dev_ctx_shared *sh)
81 {
82 #ifdef HAVE_MLX5DV_PP_ALLOC
83 	uint32_t pp[MLX5_ST_SZ_DW(set_pp_rate_limit_context)];
84 	uint64_t rate;
85 
86 	MLX5_ASSERT(!sh->txpp.pp);
87 	memset(&pp, 0, sizeof(pp));
88 	rate = NS_PER_S / sh->txpp.tick;
89 	if (rate * sh->txpp.tick != NS_PER_S)
90 		DRV_LOG(WARNING, "Packet pacing frequency is not precise.");
91 	if (sh->txpp.test) {
92 		uint32_t len;
93 
94 		len = RTE_MAX(MLX5_TXPP_TEST_PKT_SIZE,
95 			      (size_t)RTE_ETHER_MIN_LEN);
96 		MLX5_SET(set_pp_rate_limit_context, &pp,
97 			 burst_upper_bound, len);
98 		MLX5_SET(set_pp_rate_limit_context, &pp,
99 			 typical_packet_size, len);
100 		/* Convert packets per second into kilobits. */
101 		rate = (rate * len) / (1000ul / CHAR_BIT);
102 		DRV_LOG(INFO, "Packet pacing rate set to %" PRIu64, rate);
103 	}
104 	MLX5_SET(set_pp_rate_limit_context, &pp, rate_limit, rate);
105 	MLX5_SET(set_pp_rate_limit_context, &pp, rate_mode,
106 		 sh->txpp.test ? MLX5_DATA_RATE : MLX5_WQE_RATE);
107 	sh->txpp.pp = mlx5_glue->dv_alloc_pp
108 				(sh->ctx, sizeof(pp), &pp,
109 				 MLX5DV_PP_ALLOC_FLAGS_DEDICATED_INDEX);
110 	if (sh->txpp.pp == NULL) {
111 		DRV_LOG(ERR, "Failed to allocate packet pacing index.");
112 		rte_errno = errno;
113 		return -errno;
114 	}
115 	if (!sh->txpp.pp->index) {
116 		DRV_LOG(ERR, "Zero packet pacing index allocated.");
117 		mlx5_txpp_free_pp_index(sh);
118 		rte_errno = ENOTSUP;
119 		return -ENOTSUP;
120 	}
121 	sh->txpp.pp_id = sh->txpp.pp->index;
122 	return 0;
123 #else
124 	RTE_SET_USED(sh);
125 	DRV_LOG(ERR, "Allocating pacing index is not supported.");
126 	rte_errno = ENOTSUP;
127 	return -ENOTSUP;
128 #endif
129 }
130 
131 static void
132 mlx5_txpp_destroy_send_queue(struct mlx5_txpp_wq *wq)
133 {
134 	if (wq->sq)
135 		claim_zero(mlx5_devx_cmd_destroy(wq->sq));
136 	if (wq->sq_umem)
137 		claim_zero(mlx5_glue->devx_umem_dereg(wq->sq_umem));
138 	if (wq->sq_buf)
139 		mlx5_free((void *)(uintptr_t)wq->sq_buf);
140 	if (wq->cq)
141 		claim_zero(mlx5_devx_cmd_destroy(wq->cq));
142 	if (wq->cq_umem)
143 		claim_zero(mlx5_glue->devx_umem_dereg(wq->cq_umem));
144 	if (wq->cq_buf)
145 		mlx5_free((void *)(uintptr_t)wq->cq_buf);
146 	memset(wq, 0, sizeof(*wq));
147 }
148 
149 static void
150 mlx5_txpp_destroy_rearm_queue(struct mlx5_dev_ctx_shared *sh)
151 {
152 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
153 
154 	mlx5_txpp_destroy_send_queue(wq);
155 }
156 
157 static void
158 mlx5_txpp_destroy_clock_queue(struct mlx5_dev_ctx_shared *sh)
159 {
160 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
161 
162 	mlx5_txpp_destroy_send_queue(wq);
163 	if (sh->txpp.tsa) {
164 		mlx5_free(sh->txpp.tsa);
165 		sh->txpp.tsa = NULL;
166 	}
167 }
168 
169 static void
170 mlx5_txpp_doorbell_rearm_queue(struct mlx5_dev_ctx_shared *sh, uint16_t ci)
171 {
172 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
173 	union {
174 		uint32_t w32[2];
175 		uint64_t w64;
176 	} cs;
177 
178 	wq->sq_ci = ci + 1;
179 	cs.w32[0] = rte_cpu_to_be_32(rte_be_to_cpu_32
180 		   (wq->wqes[ci & (wq->sq_size - 1)].ctrl[0]) | (ci - 1) << 8);
181 	cs.w32[1] = wq->wqes[ci & (wq->sq_size - 1)].ctrl[1];
182 	/* Update SQ doorbell record with new SQ ci. */
183 	rte_compiler_barrier();
184 	*wq->sq_dbrec = rte_cpu_to_be_32(wq->sq_ci);
185 	/* Make sure the doorbell record is updated. */
186 	rte_wmb();
187 	/* Write to doorbel register to start processing. */
188 	__mlx5_uar_write64_relaxed(cs.w64, sh->tx_uar->reg_addr, NULL);
189 	rte_wmb();
190 }
191 
192 static void
193 mlx5_txpp_fill_cqe_rearm_queue(struct mlx5_dev_ctx_shared *sh)
194 {
195 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
196 	struct mlx5_cqe *cqe = (struct mlx5_cqe *)(uintptr_t)wq->cqes;
197 	uint32_t i;
198 
199 	for (i = 0; i < MLX5_TXPP_REARM_CQ_SIZE; i++) {
200 		cqe->op_own = (MLX5_CQE_INVALID << 4) | MLX5_CQE_OWNER_MASK;
201 		++cqe;
202 	}
203 }
204 
205 static void
206 mlx5_txpp_fill_wqe_rearm_queue(struct mlx5_dev_ctx_shared *sh)
207 {
208 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
209 	struct mlx5_wqe *wqe = (struct mlx5_wqe *)(uintptr_t)wq->wqes;
210 	uint32_t i;
211 
212 	for (i = 0; i < wq->sq_size; i += 2) {
213 		struct mlx5_wqe_cseg *cs;
214 		struct mlx5_wqe_qseg *qs;
215 		uint32_t index;
216 
217 		/* Build SEND_EN request with slave WQE index. */
218 		cs = &wqe[i + 0].cseg;
219 		cs->opcode = RTE_BE32(MLX5_OPCODE_SEND_EN | 0);
220 		cs->sq_ds = rte_cpu_to_be_32((wq->sq->id << 8) | 2);
221 		cs->flags = RTE_BE32(MLX5_COMP_ALWAYS <<
222 				     MLX5_COMP_MODE_OFFSET);
223 		cs->misc = RTE_BE32(0);
224 		qs = RTE_PTR_ADD(cs, sizeof(struct mlx5_wqe_cseg));
225 		index = (i * MLX5_TXPP_REARM / 2 + MLX5_TXPP_REARM) &
226 			((1 << MLX5_WQ_INDEX_WIDTH) - 1);
227 		qs->max_index = rte_cpu_to_be_32(index);
228 		qs->qpn_cqn = rte_cpu_to_be_32(sh->txpp.clock_queue.sq->id);
229 		/* Build WAIT request with slave CQE index. */
230 		cs = &wqe[i + 1].cseg;
231 		cs->opcode = RTE_BE32(MLX5_OPCODE_WAIT | 0);
232 		cs->sq_ds = rte_cpu_to_be_32((wq->sq->id << 8) | 2);
233 		cs->flags = RTE_BE32(MLX5_COMP_ONLY_ERR <<
234 				     MLX5_COMP_MODE_OFFSET);
235 		cs->misc = RTE_BE32(0);
236 		qs = RTE_PTR_ADD(cs, sizeof(struct mlx5_wqe_cseg));
237 		index = (i * MLX5_TXPP_REARM / 2 + MLX5_TXPP_REARM / 2) &
238 			((1 << MLX5_CQ_INDEX_WIDTH) - 1);
239 		qs->max_index = rte_cpu_to_be_32(index);
240 		qs->qpn_cqn = rte_cpu_to_be_32(sh->txpp.clock_queue.cq->id);
241 	}
242 }
243 
244 /* Creates the Rearm Queue to fire the requests to Clock Queue in realtime. */
245 static int
246 mlx5_txpp_create_rearm_queue(struct mlx5_dev_ctx_shared *sh)
247 {
248 	struct mlx5_devx_create_sq_attr sq_attr = { 0 };
249 	struct mlx5_devx_modify_sq_attr msq_attr = { 0 };
250 	struct mlx5_devx_cq_attr cq_attr = { 0 };
251 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
252 	size_t page_size = sysconf(_SC_PAGESIZE);
253 	uint32_t umem_size, umem_dbrec;
254 	int ret;
255 
256 	/* Allocate memory buffer for CQEs and doorbell record. */
257 	umem_size = sizeof(struct mlx5_cqe) * MLX5_TXPP_REARM_CQ_SIZE;
258 	umem_dbrec = RTE_ALIGN(umem_size, MLX5_DBR_SIZE);
259 	umem_size += MLX5_DBR_SIZE;
260 	wq->cq_buf = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO, umem_size,
261 				 page_size, sh->numa_node);
262 	if (!wq->cq_buf) {
263 		DRV_LOG(ERR, "Failed to allocate memory for Rearm Queue.");
264 		return -ENOMEM;
265 	}
266 	/* Register allocated buffer in user space with DevX. */
267 	wq->cq_umem = mlx5_glue->devx_umem_reg(sh->ctx,
268 					       (void *)(uintptr_t)wq->cq_buf,
269 					       umem_size,
270 					       IBV_ACCESS_LOCAL_WRITE);
271 	if (!wq->cq_umem) {
272 		rte_errno = errno;
273 		DRV_LOG(ERR, "Failed to register umem for Rearm Queue.");
274 		goto error;
275 	}
276 	/* Create completion queue object for Rearm Queue. */
277 	cq_attr.cqe_size = (sizeof(struct mlx5_cqe) == 128) ?
278 			    MLX5_CQE_SIZE_128B : MLX5_CQE_SIZE_64B;
279 	cq_attr.uar_page_id = sh->tx_uar->page_id;
280 	cq_attr.eqn = sh->txpp.eqn;
281 	cq_attr.q_umem_valid = 1;
282 	cq_attr.q_umem_offset = 0;
283 	cq_attr.q_umem_id = mlx5_os_get_umem_id(wq->cq_umem);
284 	cq_attr.db_umem_valid = 1;
285 	cq_attr.db_umem_offset = umem_dbrec;
286 	cq_attr.db_umem_id = mlx5_os_get_umem_id(wq->cq_umem);
287 	cq_attr.log_cq_size = rte_log2_u32(MLX5_TXPP_REARM_CQ_SIZE);
288 	cq_attr.log_page_size = rte_log2_u32(page_size);
289 	wq->cq = mlx5_devx_cmd_create_cq(sh->ctx, &cq_attr);
290 	if (!wq->cq) {
291 		rte_errno = errno;
292 		DRV_LOG(ERR, "Failed to create CQ for Rearm Queue.");
293 		goto error;
294 	}
295 	wq->cq_dbrec = RTE_PTR_ADD(wq->cq_buf, umem_dbrec);
296 	wq->cq_ci = 0;
297 	wq->arm_sn = 0;
298 	/* Mark all CQEs initially as invalid. */
299 	mlx5_txpp_fill_cqe_rearm_queue(sh);
300 	/*
301 	 * Allocate memory buffer for Send Queue WQEs.
302 	 * There should be no WQE leftovers in the cyclic queue.
303 	 */
304 	wq->sq_size = MLX5_TXPP_REARM_SQ_SIZE;
305 	MLX5_ASSERT(wq->sq_size == (1 << log2above(wq->sq_size)));
306 	umem_size =  MLX5_WQE_SIZE * wq->sq_size;
307 	umem_dbrec = RTE_ALIGN(umem_size, MLX5_DBR_SIZE);
308 	umem_size += MLX5_DBR_SIZE;
309 	wq->sq_buf = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO, umem_size,
310 				 page_size, sh->numa_node);
311 	if (!wq->sq_buf) {
312 		DRV_LOG(ERR, "Failed to allocate memory for Rearm Queue.");
313 		rte_errno = ENOMEM;
314 		goto error;
315 	}
316 	/* Register allocated buffer in user space with DevX. */
317 	wq->sq_umem = mlx5_glue->devx_umem_reg(sh->ctx,
318 					       (void *)(uintptr_t)wq->sq_buf,
319 					       umem_size,
320 					       IBV_ACCESS_LOCAL_WRITE);
321 	if (!wq->sq_umem) {
322 		rte_errno = errno;
323 		DRV_LOG(ERR, "Failed to register umem for Rearm Queue.");
324 		goto error;
325 	}
326 	/* Create send queue object for Rearm Queue. */
327 	sq_attr.state = MLX5_SQC_STATE_RST;
328 	sq_attr.tis_lst_sz = 1;
329 	sq_attr.tis_num = sh->tis->id;
330 	sq_attr.cqn = wq->cq->id;
331 	sq_attr.cd_master = 1;
332 	sq_attr.wq_attr.uar_page = sh->tx_uar->page_id;
333 	sq_attr.wq_attr.wq_type = MLX5_WQ_TYPE_CYCLIC;
334 	sq_attr.wq_attr.pd = sh->pdn;
335 	sq_attr.wq_attr.log_wq_stride = rte_log2_u32(MLX5_WQE_SIZE);
336 	sq_attr.wq_attr.log_wq_sz = rte_log2_u32(wq->sq_size);
337 	sq_attr.wq_attr.dbr_umem_valid = 1;
338 	sq_attr.wq_attr.dbr_addr = umem_dbrec;
339 	sq_attr.wq_attr.dbr_umem_id = mlx5_os_get_umem_id(wq->sq_umem);
340 	sq_attr.wq_attr.wq_umem_valid = 1;
341 	sq_attr.wq_attr.wq_umem_id = mlx5_os_get_umem_id(wq->sq_umem);
342 	sq_attr.wq_attr.wq_umem_offset = 0;
343 	wq->sq = mlx5_devx_cmd_create_sq(sh->ctx, &sq_attr);
344 	if (!wq->sq) {
345 		rte_errno = errno;
346 		DRV_LOG(ERR, "Failed to create SQ for Rearm Queue.");
347 		goto error;
348 	}
349 	wq->sq_dbrec = RTE_PTR_ADD(wq->sq_buf, umem_dbrec +
350 				   MLX5_SND_DBR * sizeof(uint32_t));
351 	/* Build the WQEs in the Send Queue before goto Ready state. */
352 	mlx5_txpp_fill_wqe_rearm_queue(sh);
353 	/* Change queue state to ready. */
354 	msq_attr.sq_state = MLX5_SQC_STATE_RST;
355 	msq_attr.state = MLX5_SQC_STATE_RDY;
356 	ret = mlx5_devx_cmd_modify_sq(wq->sq, &msq_attr);
357 	if (ret) {
358 		DRV_LOG(ERR, "Failed to set SQ ready state Rearm Queue.");
359 		goto error;
360 	}
361 	return 0;
362 error:
363 	ret = -rte_errno;
364 	mlx5_txpp_destroy_rearm_queue(sh);
365 	rte_errno = -ret;
366 	return ret;
367 }
368 
369 static void
370 mlx5_txpp_fill_wqe_clock_queue(struct mlx5_dev_ctx_shared *sh)
371 {
372 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
373 	struct mlx5_wqe *wqe = (struct mlx5_wqe *)(uintptr_t)wq->wqes;
374 	struct mlx5_wqe_cseg *cs = &wqe->cseg;
375 	uint32_t wqe_size, opcode, i;
376 	uint8_t *dst;
377 
378 	/* For test purposes fill the WQ with SEND inline packet. */
379 	if (sh->txpp.test) {
380 		wqe_size = RTE_ALIGN(MLX5_TXPP_TEST_PKT_SIZE +
381 				     MLX5_WQE_CSEG_SIZE +
382 				     2 * MLX5_WQE_ESEG_SIZE -
383 				     MLX5_ESEG_MIN_INLINE_SIZE,
384 				     MLX5_WSEG_SIZE);
385 		opcode = MLX5_OPCODE_SEND;
386 	} else {
387 		wqe_size = MLX5_WSEG_SIZE;
388 		opcode = MLX5_OPCODE_NOP;
389 	}
390 	cs->opcode = rte_cpu_to_be_32(opcode | 0); /* Index is ignored. */
391 	cs->sq_ds = rte_cpu_to_be_32((wq->sq->id << 8) |
392 				     (wqe_size / MLX5_WSEG_SIZE));
393 	cs->flags = RTE_BE32(MLX5_COMP_ALWAYS << MLX5_COMP_MODE_OFFSET);
394 	cs->misc = RTE_BE32(0);
395 	wqe_size = RTE_ALIGN(wqe_size, MLX5_WQE_SIZE);
396 	if (sh->txpp.test) {
397 		struct mlx5_wqe_eseg *es = &wqe->eseg;
398 		struct rte_ether_hdr *eth_hdr;
399 		struct rte_ipv4_hdr *ip_hdr;
400 		struct rte_udp_hdr *udp_hdr;
401 
402 		/* Build the inline test packet pattern. */
403 		MLX5_ASSERT(wqe_size <= MLX5_WQE_SIZE_MAX);
404 		MLX5_ASSERT(MLX5_TXPP_TEST_PKT_SIZE >=
405 				(sizeof(struct rte_ether_hdr) +
406 				 sizeof(struct rte_ipv4_hdr)));
407 		es->flags = 0;
408 		es->cs_flags = MLX5_ETH_WQE_L3_CSUM | MLX5_ETH_WQE_L4_CSUM;
409 		es->swp_offs = 0;
410 		es->metadata = 0;
411 		es->swp_flags = 0;
412 		es->mss = 0;
413 		es->inline_hdr_sz = RTE_BE16(MLX5_TXPP_TEST_PKT_SIZE);
414 		/* Build test packet L2 header (Ethernet). */
415 		dst = (uint8_t *)&es->inline_data;
416 		eth_hdr = (struct rte_ether_hdr *)dst;
417 		rte_eth_random_addr(&eth_hdr->d_addr.addr_bytes[0]);
418 		rte_eth_random_addr(&eth_hdr->s_addr.addr_bytes[0]);
419 		eth_hdr->ether_type = rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4);
420 		/* Build test packet L3 header (IP v4). */
421 		dst += sizeof(struct rte_ether_hdr);
422 		ip_hdr = (struct rte_ipv4_hdr *)dst;
423 		ip_hdr->version_ihl = RTE_IPV4_VHL_DEF;
424 		ip_hdr->type_of_service = 0;
425 		ip_hdr->fragment_offset = 0;
426 		ip_hdr->time_to_live = 64;
427 		ip_hdr->next_proto_id = IPPROTO_UDP;
428 		ip_hdr->packet_id = 0;
429 		ip_hdr->total_length = RTE_BE16(MLX5_TXPP_TEST_PKT_SIZE -
430 						sizeof(struct rte_ether_hdr));
431 		/* use RFC5735 / RFC2544 reserved network test addresses */
432 		ip_hdr->src_addr = RTE_BE32((198U << 24) | (18 << 16) |
433 					    (0 << 8) | 1);
434 		ip_hdr->dst_addr = RTE_BE32((198U << 24) | (18 << 16) |
435 					    (0 << 8) | 2);
436 		if (MLX5_TXPP_TEST_PKT_SIZE <
437 					(sizeof(struct rte_ether_hdr) +
438 					 sizeof(struct rte_ipv4_hdr) +
439 					 sizeof(struct rte_udp_hdr)))
440 			goto wcopy;
441 		/* Build test packet L4 header (UDP). */
442 		dst += sizeof(struct rte_ipv4_hdr);
443 		udp_hdr = (struct rte_udp_hdr *)dst;
444 		udp_hdr->src_port = RTE_BE16(9); /* RFC863 Discard. */
445 		udp_hdr->dst_port = RTE_BE16(9);
446 		udp_hdr->dgram_len = RTE_BE16(MLX5_TXPP_TEST_PKT_SIZE -
447 					      sizeof(struct rte_ether_hdr) -
448 					      sizeof(struct rte_ipv4_hdr));
449 		udp_hdr->dgram_cksum = 0;
450 		/* Fill the test packet data. */
451 		dst += sizeof(struct rte_udp_hdr);
452 		for (i = sizeof(struct rte_ether_hdr) +
453 			sizeof(struct rte_ipv4_hdr) +
454 			sizeof(struct rte_udp_hdr);
455 				i < MLX5_TXPP_TEST_PKT_SIZE; i++)
456 			*dst++ = (uint8_t)(i & 0xFF);
457 	}
458 wcopy:
459 	/* Duplicate the pattern to the next WQEs. */
460 	dst = (uint8_t *)(uintptr_t)wq->sq_buf;
461 	for (i = 1; i < MLX5_TXPP_CLKQ_SIZE; i++) {
462 		dst += wqe_size;
463 		rte_memcpy(dst, (void *)(uintptr_t)wq->sq_buf, wqe_size);
464 	}
465 }
466 
467 /* Creates the Clock Queue for packet pacing, returns zero on success. */
468 static int
469 mlx5_txpp_create_clock_queue(struct mlx5_dev_ctx_shared *sh)
470 {
471 	struct mlx5_devx_create_sq_attr sq_attr = { 0 };
472 	struct mlx5_devx_modify_sq_attr msq_attr = { 0 };
473 	struct mlx5_devx_cq_attr cq_attr = { 0 };
474 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
475 	size_t page_size = sysconf(_SC_PAGESIZE);
476 	uint32_t umem_size, umem_dbrec;
477 	int ret;
478 
479 	sh->txpp.tsa = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO,
480 				   MLX5_TXPP_REARM_SQ_SIZE *
481 				   sizeof(struct mlx5_txpp_ts),
482 				   0, sh->numa_node);
483 	if (!sh->txpp.tsa) {
484 		DRV_LOG(ERR, "Failed to allocate memory for CQ stats.");
485 		return -ENOMEM;
486 	}
487 	sh->txpp.ts_p = 0;
488 	sh->txpp.ts_n = 0;
489 	/* Allocate memory buffer for CQEs and doorbell record. */
490 	umem_size = sizeof(struct mlx5_cqe) * MLX5_TXPP_CLKQ_SIZE;
491 	umem_dbrec = RTE_ALIGN(umem_size, MLX5_DBR_SIZE);
492 	umem_size += MLX5_DBR_SIZE;
493 	wq->cq_buf = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO, umem_size,
494 					page_size, sh->numa_node);
495 	if (!wq->cq_buf) {
496 		DRV_LOG(ERR, "Failed to allocate memory for Clock Queue.");
497 		return -ENOMEM;
498 	}
499 	/* Register allocated buffer in user space with DevX. */
500 	wq->cq_umem = mlx5_glue->devx_umem_reg(sh->ctx,
501 					       (void *)(uintptr_t)wq->cq_buf,
502 					       umem_size,
503 					       IBV_ACCESS_LOCAL_WRITE);
504 	if (!wq->cq_umem) {
505 		rte_errno = errno;
506 		DRV_LOG(ERR, "Failed to register umem for Clock Queue.");
507 		goto error;
508 	}
509 	/* Create completion queue object for Clock Queue. */
510 	cq_attr.cqe_size = (sizeof(struct mlx5_cqe) == 128) ?
511 			    MLX5_CQE_SIZE_128B : MLX5_CQE_SIZE_64B;
512 	cq_attr.use_first_only = 1;
513 	cq_attr.overrun_ignore = 1;
514 	cq_attr.uar_page_id = sh->tx_uar->page_id;
515 	cq_attr.eqn = sh->txpp.eqn;
516 	cq_attr.q_umem_valid = 1;
517 	cq_attr.q_umem_offset = 0;
518 	cq_attr.q_umem_id = wq->cq_umem->umem_id;
519 	cq_attr.db_umem_valid = 1;
520 	cq_attr.db_umem_offset = umem_dbrec;
521 	cq_attr.db_umem_id = wq->cq_umem->umem_id;
522 	cq_attr.log_cq_size = rte_log2_u32(MLX5_TXPP_CLKQ_SIZE);
523 	cq_attr.log_page_size = rte_log2_u32(page_size);
524 	wq->cq = mlx5_devx_cmd_create_cq(sh->ctx, &cq_attr);
525 	if (!wq->cq) {
526 		rte_errno = errno;
527 		DRV_LOG(ERR, "Failed to create CQ for Clock Queue.");
528 		goto error;
529 	}
530 	wq->cq_dbrec = RTE_PTR_ADD(wq->cq_buf, umem_dbrec);
531 	wq->cq_ci = 0;
532 	/* Allocate memory buffer for Send Queue WQEs. */
533 	if (sh->txpp.test) {
534 		wq->sq_size = RTE_ALIGN(MLX5_TXPP_TEST_PKT_SIZE +
535 					MLX5_WQE_CSEG_SIZE +
536 					2 * MLX5_WQE_ESEG_SIZE -
537 					MLX5_ESEG_MIN_INLINE_SIZE,
538 					MLX5_WQE_SIZE) / MLX5_WQE_SIZE;
539 		wq->sq_size *= MLX5_TXPP_CLKQ_SIZE;
540 	} else {
541 		wq->sq_size = MLX5_TXPP_CLKQ_SIZE;
542 	}
543 	/* There should not be WQE leftovers in the cyclic queue. */
544 	MLX5_ASSERT(wq->sq_size == (1 << log2above(wq->sq_size)));
545 	umem_size =  MLX5_WQE_SIZE * wq->sq_size;
546 	umem_dbrec = RTE_ALIGN(umem_size, MLX5_DBR_SIZE);
547 	umem_size += MLX5_DBR_SIZE;
548 	wq->sq_buf = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO, umem_size,
549 				 page_size, sh->numa_node);
550 	if (!wq->sq_buf) {
551 		DRV_LOG(ERR, "Failed to allocate memory for Clock Queue.");
552 		rte_errno = ENOMEM;
553 		goto error;
554 	}
555 	/* Register allocated buffer in user space with DevX. */
556 	wq->sq_umem = mlx5_glue->devx_umem_reg(sh->ctx,
557 					       (void *)(uintptr_t)wq->sq_buf,
558 					       umem_size,
559 					       IBV_ACCESS_LOCAL_WRITE);
560 	if (!wq->sq_umem) {
561 		rte_errno = errno;
562 		DRV_LOG(ERR, "Failed to register umem for Clock Queue.");
563 		goto error;
564 	}
565 	/* Create send queue object for Clock Queue. */
566 	if (sh->txpp.test) {
567 		sq_attr.tis_lst_sz = 1;
568 		sq_attr.tis_num = sh->tis->id;
569 		sq_attr.non_wire = 0;
570 		sq_attr.static_sq_wq = 1;
571 	} else {
572 		sq_attr.non_wire = 1;
573 		sq_attr.static_sq_wq = 1;
574 	}
575 	sq_attr.state = MLX5_SQC_STATE_RST;
576 	sq_attr.cqn = wq->cq->id;
577 	sq_attr.packet_pacing_rate_limit_index = sh->txpp.pp_id;
578 	sq_attr.wq_attr.cd_slave = 1;
579 	sq_attr.wq_attr.uar_page = sh->tx_uar->page_id;
580 	sq_attr.wq_attr.wq_type = MLX5_WQ_TYPE_CYCLIC;
581 	sq_attr.wq_attr.pd = sh->pdn;
582 	sq_attr.wq_attr.log_wq_stride = rte_log2_u32(MLX5_WQE_SIZE);
583 	sq_attr.wq_attr.log_wq_sz = rte_log2_u32(wq->sq_size);
584 	sq_attr.wq_attr.dbr_umem_valid = 1;
585 	sq_attr.wq_attr.dbr_addr = umem_dbrec;
586 	sq_attr.wq_attr.dbr_umem_id = wq->sq_umem->umem_id;
587 	sq_attr.wq_attr.wq_umem_valid = 1;
588 	sq_attr.wq_attr.wq_umem_id = wq->sq_umem->umem_id;
589 	/* umem_offset must be zero for static_sq_wq queue. */
590 	sq_attr.wq_attr.wq_umem_offset = 0;
591 	wq->sq = mlx5_devx_cmd_create_sq(sh->ctx, &sq_attr);
592 	if (!wq->sq) {
593 		rte_errno = errno;
594 		DRV_LOG(ERR, "Failed to create SQ for Clock Queue.");
595 		goto error;
596 	}
597 	wq->sq_dbrec = RTE_PTR_ADD(wq->sq_buf, umem_dbrec +
598 				   MLX5_SND_DBR * sizeof(uint32_t));
599 	/* Build the WQEs in the Send Queue before goto Ready state. */
600 	mlx5_txpp_fill_wqe_clock_queue(sh);
601 	/* Change queue state to ready. */
602 	msq_attr.sq_state = MLX5_SQC_STATE_RST;
603 	msq_attr.state = MLX5_SQC_STATE_RDY;
604 	wq->sq_ci = 0;
605 	ret = mlx5_devx_cmd_modify_sq(wq->sq, &msq_attr);
606 	if (ret) {
607 		DRV_LOG(ERR, "Failed to set SQ ready state Clock Queue.");
608 		goto error;
609 	}
610 	return 0;
611 error:
612 	ret = -rte_errno;
613 	mlx5_txpp_destroy_clock_queue(sh);
614 	rte_errno = -ret;
615 	return ret;
616 }
617 
618 /* Enable notification from the Rearm Queue CQ. */
619 static inline void
620 mlx5_txpp_cq_arm(struct mlx5_dev_ctx_shared *sh)
621 {
622 	struct mlx5_txpp_wq *aq = &sh->txpp.rearm_queue;
623 	uint32_t arm_sn = aq->arm_sn << MLX5_CQ_SQN_OFFSET;
624 	uint32_t db_hi = arm_sn | MLX5_CQ_DBR_CMD_ALL | aq->cq_ci;
625 	uint64_t db_be = rte_cpu_to_be_64(((uint64_t)db_hi << 32) | aq->cq->id);
626 	uint32_t *addr = RTE_PTR_ADD(sh->tx_uar->base_addr, MLX5_CQ_DOORBELL);
627 
628 	rte_compiler_barrier();
629 	aq->cq_dbrec[MLX5_CQ_ARM_DB] = rte_cpu_to_be_32(db_hi);
630 	rte_wmb();
631 #ifdef RTE_ARCH_64
632 	*(uint64_t *)addr = db_be;
633 #else
634 	*(uint32_t *)addr = db_be;
635 	rte_io_wmb();
636 	*((uint32_t *)addr + 1) = db_be >> 32;
637 #endif
638 	aq->arm_sn++;
639 }
640 
641 static inline void
642 mlx5_atomic_read_cqe(rte_int128_t *from, rte_int128_t *ts)
643 {
644 	/*
645 	 * The only CQE of Clock Queue is being continuously
646 	 * update by hardware with soecified rate. We have to
647 	 * read timestump and WQE completion index atomically.
648 	 */
649 #if defined(RTE_ARCH_X86_64) || defined(RTE_ARCH_ARM64)
650 	rte_int128_t src;
651 
652 	memset(&src, 0, sizeof(src));
653 	*ts = src;
654 	/* if (*from == *ts) *from = *src else *ts = *from; */
655 	rte_atomic128_cmp_exchange(from, ts, &src, 0,
656 				   __ATOMIC_RELAXED, __ATOMIC_RELAXED);
657 #else
658 	rte_atomic64_t *cqe = (rte_atomic64_t *)from;
659 
660 	/* Power architecture does not support 16B compare-and-swap. */
661 	for (;;) {
662 		int64_t tm, op;
663 		int64_t *ps;
664 
665 		rte_compiler_barrier();
666 		tm = rte_atomic64_read(cqe + 0);
667 		op = rte_atomic64_read(cqe + 1);
668 		rte_compiler_barrier();
669 		if (tm != rte_atomic64_read(cqe + 0))
670 			continue;
671 		if (op != rte_atomic64_read(cqe + 1))
672 			continue;
673 		ps = (int64_t *)ts;
674 		ps[0] = tm;
675 		ps[1] = op;
676 		return;
677 	}
678 #endif
679 }
680 
681 /* Stores timestamp in the cache structure to share data with datapath. */
682 static inline void
683 mlx5_txpp_cache_timestamp(struct mlx5_dev_ctx_shared *sh,
684 			   uint64_t ts, uint64_t ci)
685 {
686 	ci = ci << (64 - MLX5_CQ_INDEX_WIDTH);
687 	ci |= (ts << MLX5_CQ_INDEX_WIDTH) >> MLX5_CQ_INDEX_WIDTH;
688 	rte_compiler_barrier();
689 	rte_atomic64_set(&sh->txpp.ts.ts, ts);
690 	rte_atomic64_set(&sh->txpp.ts.ci_ts, ci);
691 	rte_wmb();
692 }
693 
694 /* Reads timestamp from Clock Queue CQE and stores in the cache. */
695 static inline void
696 mlx5_txpp_update_timestamp(struct mlx5_dev_ctx_shared *sh)
697 {
698 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
699 	struct mlx5_cqe *cqe = (struct mlx5_cqe *)(uintptr_t)wq->cqes;
700 	union {
701 		rte_int128_t u128;
702 		struct mlx5_cqe_ts cts;
703 	} to;
704 	uint64_t ts;
705 	uint16_t ci;
706 
707 	static_assert(sizeof(struct mlx5_cqe_ts) == sizeof(rte_int128_t),
708 		      "Wrong timestamp CQE part size");
709 	mlx5_atomic_read_cqe((rte_int128_t *)&cqe->timestamp, &to.u128);
710 	if (to.cts.op_own >> 4) {
711 		DRV_LOG(DEBUG, "Clock Queue error sync lost.");
712 		rte_atomic32_inc(&sh->txpp.err_clock_queue);
713 		sh->txpp.sync_lost = 1;
714 		return;
715 	}
716 	ci = rte_be_to_cpu_16(to.cts.wqe_counter);
717 	ts = rte_be_to_cpu_64(to.cts.timestamp);
718 	ts = mlx5_txpp_convert_rx_ts(sh, ts);
719 	wq->cq_ci += (ci - wq->sq_ci) & UINT16_MAX;
720 	wq->sq_ci = ci;
721 	mlx5_txpp_cache_timestamp(sh, ts, wq->cq_ci);
722 }
723 
724 /* Waits for the first completion on Clock Queue to init timestamp. */
725 static inline void
726 mlx5_txpp_init_timestamp(struct mlx5_dev_ctx_shared *sh)
727 {
728 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
729 	uint32_t wait;
730 
731 	sh->txpp.ts_p = 0;
732 	sh->txpp.ts_n = 0;
733 	for (wait = 0; wait < MLX5_TXPP_WAIT_INIT_TS; wait++) {
734 		struct timespec onems;
735 
736 		mlx5_txpp_update_timestamp(sh);
737 		if (wq->sq_ci)
738 			return;
739 		/* Wait one millisecond and try again. */
740 		onems.tv_sec = 0;
741 		onems.tv_nsec = NS_PER_S / MS_PER_S;
742 		nanosleep(&onems, 0);
743 	}
744 	DRV_LOG(ERR, "Unable to initialize timestamp.");
745 	sh->txpp.sync_lost = 1;
746 }
747 
748 #ifdef HAVE_IBV_DEVX_EVENT
749 /* Gather statistics for timestamp from Clock Queue CQE. */
750 static inline void
751 mlx5_txpp_gather_timestamp(struct mlx5_dev_ctx_shared *sh)
752 {
753 	/* Check whether we have a valid timestamp. */
754 	if (!sh->txpp.clock_queue.sq_ci && !sh->txpp.ts_n)
755 		return;
756 	MLX5_ASSERT(sh->txpp.ts_p < MLX5_TXPP_REARM_SQ_SIZE);
757 	sh->txpp.tsa[sh->txpp.ts_p] = sh->txpp.ts;
758 	if (++sh->txpp.ts_p >= MLX5_TXPP_REARM_SQ_SIZE)
759 		sh->txpp.ts_p = 0;
760 	if (sh->txpp.ts_n < MLX5_TXPP_REARM_SQ_SIZE)
761 		++sh->txpp.ts_n;
762 }
763 
764 /* Handles Rearm Queue completions in periodic service. */
765 static __rte_always_inline void
766 mlx5_txpp_handle_rearm_queue(struct mlx5_dev_ctx_shared *sh)
767 {
768 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
769 	uint32_t cq_ci = wq->cq_ci;
770 	bool error = false;
771 	int ret;
772 
773 	do {
774 		volatile struct mlx5_cqe *cqe;
775 
776 		cqe = &wq->cqes[cq_ci & (MLX5_TXPP_REARM_CQ_SIZE - 1)];
777 		ret = check_cqe(cqe, MLX5_TXPP_REARM_CQ_SIZE, cq_ci);
778 		switch (ret) {
779 		case MLX5_CQE_STATUS_ERR:
780 			error = true;
781 			++cq_ci;
782 			break;
783 		case MLX5_CQE_STATUS_SW_OWN:
784 			wq->sq_ci += 2;
785 			++cq_ci;
786 			break;
787 		case MLX5_CQE_STATUS_HW_OWN:
788 			break;
789 		default:
790 			MLX5_ASSERT(false);
791 			break;
792 		}
793 	} while (ret != MLX5_CQE_STATUS_HW_OWN);
794 	if (likely(cq_ci != wq->cq_ci)) {
795 		/* Check whether we have missed interrupts. */
796 		if (cq_ci - wq->cq_ci != 1) {
797 			DRV_LOG(DEBUG, "Rearm Queue missed interrupt.");
798 			rte_atomic32_inc(&sh->txpp.err_miss_int);
799 			/* Check sync lost on wqe index. */
800 			if (cq_ci - wq->cq_ci >=
801 				(((1UL << MLX5_WQ_INDEX_WIDTH) /
802 				  MLX5_TXPP_REARM) - 1))
803 				error = 1;
804 		}
805 		/* Update doorbell record to notify hardware. */
806 		rte_compiler_barrier();
807 		*wq->cq_dbrec = rte_cpu_to_be_32(cq_ci);
808 		rte_wmb();
809 		wq->cq_ci = cq_ci;
810 		/* Fire new requests to Rearm Queue. */
811 		if (error) {
812 			DRV_LOG(DEBUG, "Rearm Queue error sync lost.");
813 			rte_atomic32_inc(&sh->txpp.err_rearm_queue);
814 			sh->txpp.sync_lost = 1;
815 		}
816 	}
817 }
818 
819 /* Handles Clock Queue completions in periodic service. */
820 static __rte_always_inline void
821 mlx5_txpp_handle_clock_queue(struct mlx5_dev_ctx_shared *sh)
822 {
823 	mlx5_txpp_update_timestamp(sh);
824 	mlx5_txpp_gather_timestamp(sh);
825 }
826 #endif
827 
828 /* Invoked periodically on Rearm Queue completions. */
829 void
830 mlx5_txpp_interrupt_handler(void *cb_arg)
831 {
832 #ifndef HAVE_IBV_DEVX_EVENT
833 	RTE_SET_USED(cb_arg);
834 	return;
835 #else
836 	struct mlx5_dev_ctx_shared *sh = cb_arg;
837 	union {
838 		struct mlx5dv_devx_async_event_hdr event_resp;
839 		uint8_t buf[sizeof(struct mlx5dv_devx_async_event_hdr) + 128];
840 	} out;
841 
842 	MLX5_ASSERT(rte_eal_process_type() == RTE_PROC_PRIMARY);
843 	/* Process events in the loop. Only rearm completions are expected. */
844 	while (mlx5_glue->devx_get_event
845 				(sh->txpp.echan,
846 				 &out.event_resp,
847 				 sizeof(out.buf)) >=
848 				 (ssize_t)sizeof(out.event_resp.cookie)) {
849 		mlx5_txpp_handle_rearm_queue(sh);
850 		mlx5_txpp_handle_clock_queue(sh);
851 		mlx5_txpp_cq_arm(sh);
852 		mlx5_txpp_doorbell_rearm_queue
853 					(sh, sh->txpp.rearm_queue.sq_ci - 1);
854 	}
855 #endif /* HAVE_IBV_DEVX_ASYNC */
856 }
857 
858 static void
859 mlx5_txpp_stop_service(struct mlx5_dev_ctx_shared *sh)
860 {
861 	if (!sh->txpp.intr_handle.fd)
862 		return;
863 	mlx5_intr_callback_unregister(&sh->txpp.intr_handle,
864 				      mlx5_txpp_interrupt_handler, sh);
865 	sh->txpp.intr_handle.fd = 0;
866 }
867 
868 /* Attach interrupt handler and fires first request to Rearm Queue. */
869 static int
870 mlx5_txpp_start_service(struct mlx5_dev_ctx_shared *sh)
871 {
872 	uint16_t event_nums[1] = {0};
873 	int flags;
874 	int ret;
875 
876 	rte_atomic32_set(&sh->txpp.err_miss_int, 0);
877 	rte_atomic32_set(&sh->txpp.err_rearm_queue, 0);
878 	rte_atomic32_set(&sh->txpp.err_clock_queue, 0);
879 	rte_atomic32_set(&sh->txpp.err_ts_past, 0);
880 	rte_atomic32_set(&sh->txpp.err_ts_future, 0);
881 	/* Attach interrupt handler to process Rearm Queue completions. */
882 	flags = fcntl(sh->txpp.echan->fd, F_GETFL);
883 	ret = fcntl(sh->txpp.echan->fd, F_SETFL, flags | O_NONBLOCK);
884 	if (ret) {
885 		DRV_LOG(ERR, "Failed to change event channel FD.");
886 		rte_errno = errno;
887 		return -rte_errno;
888 	}
889 	memset(&sh->txpp.intr_handle, 0, sizeof(sh->txpp.intr_handle));
890 	sh->txpp.intr_handle.fd = sh->txpp.echan->fd;
891 	sh->txpp.intr_handle.type = RTE_INTR_HANDLE_EXT;
892 	if (rte_intr_callback_register(&sh->txpp.intr_handle,
893 				       mlx5_txpp_interrupt_handler, sh)) {
894 		sh->txpp.intr_handle.fd = 0;
895 		DRV_LOG(ERR, "Failed to register CQE interrupt %d.", rte_errno);
896 		return -rte_errno;
897 	}
898 	/* Subscribe CQ event to the event channel controlled by the driver. */
899 	ret = mlx5_glue->devx_subscribe_devx_event(sh->txpp.echan,
900 						   sh->txpp.rearm_queue.cq->obj,
901 						   sizeof(event_nums),
902 						   event_nums, 0);
903 	if (ret) {
904 		DRV_LOG(ERR, "Failed to subscribe CQE event.");
905 		rte_errno = errno;
906 		return -errno;
907 	}
908 	/* Enable interrupts in the CQ. */
909 	mlx5_txpp_cq_arm(sh);
910 	/* Fire the first request on Rearm Queue. */
911 	mlx5_txpp_doorbell_rearm_queue(sh, sh->txpp.rearm_queue.sq_size - 1);
912 	mlx5_txpp_init_timestamp(sh);
913 	return 0;
914 }
915 
916 /*
917  * The routine initializes the packet pacing infrastructure:
918  * - allocates PP context
919  * - Clock CQ/SQ
920  * - Rearm CQ/SQ
921  * - attaches rearm interrupt handler
922  * - starts Clock Queue
923  *
924  * Returns 0 on success, negative otherwise
925  */
926 static int
927 mlx5_txpp_create(struct mlx5_dev_ctx_shared *sh, struct mlx5_priv *priv)
928 {
929 	int tx_pp = priv->config.tx_pp;
930 	int ret;
931 
932 	/* Store the requested pacing parameters. */
933 	sh->txpp.tick = tx_pp >= 0 ? tx_pp : -tx_pp;
934 	sh->txpp.test = !!(tx_pp < 0);
935 	sh->txpp.skew = priv->config.tx_skew;
936 	sh->txpp.freq = priv->config.hca_attr.dev_freq_khz;
937 	ret = mlx5_txpp_create_eqn(sh);
938 	if (ret)
939 		goto exit;
940 	ret = mlx5_txpp_alloc_pp_index(sh);
941 	if (ret)
942 		goto exit;
943 	ret = mlx5_txpp_create_clock_queue(sh);
944 	if (ret)
945 		goto exit;
946 	ret = mlx5_txpp_create_rearm_queue(sh);
947 	if (ret)
948 		goto exit;
949 	ret = mlx5_txpp_start_service(sh);
950 	if (ret)
951 		goto exit;
952 exit:
953 	if (ret) {
954 		mlx5_txpp_stop_service(sh);
955 		mlx5_txpp_destroy_rearm_queue(sh);
956 		mlx5_txpp_destroy_clock_queue(sh);
957 		mlx5_txpp_free_pp_index(sh);
958 		mlx5_txpp_destroy_eqn(sh);
959 		sh->txpp.tick = 0;
960 		sh->txpp.test = 0;
961 		sh->txpp.skew = 0;
962 	}
963 	return ret;
964 }
965 
966 /*
967  * The routine destroys the packet pacing infrastructure:
968  * - detaches rearm interrupt handler
969  * - Rearm CQ/SQ
970  * - Clock CQ/SQ
971  * - PP context
972  */
973 static void
974 mlx5_txpp_destroy(struct mlx5_dev_ctx_shared *sh)
975 {
976 	mlx5_txpp_stop_service(sh);
977 	mlx5_txpp_destroy_rearm_queue(sh);
978 	mlx5_txpp_destroy_clock_queue(sh);
979 	mlx5_txpp_free_pp_index(sh);
980 	mlx5_txpp_destroy_eqn(sh);
981 	sh->txpp.tick = 0;
982 	sh->txpp.test = 0;
983 	sh->txpp.skew = 0;
984 }
985 
986 /**
987  * Creates and starts packet pacing infrastructure on specified device.
988  *
989  * @param dev
990  *   Pointer to Ethernet device structure.
991  *
992  * @return
993  *   0 on success, a negative errno value otherwise and rte_errno is set.
994  */
995 int
996 mlx5_txpp_start(struct rte_eth_dev *dev)
997 {
998 	struct mlx5_priv *priv = dev->data->dev_private;
999 	struct mlx5_dev_ctx_shared *sh = priv->sh;
1000 	int err = 0;
1001 	int ret;
1002 
1003 	if (!priv->config.tx_pp) {
1004 		/* Packet pacing is not requested for the device. */
1005 		MLX5_ASSERT(priv->txpp_en == 0);
1006 		return 0;
1007 	}
1008 	if (priv->txpp_en) {
1009 		/* Packet pacing is already enabled for the device. */
1010 		MLX5_ASSERT(sh->txpp.refcnt);
1011 		return 0;
1012 	}
1013 	if (priv->config.tx_pp > 0) {
1014 		ret = rte_mbuf_dynflag_lookup
1015 				(RTE_MBUF_DYNFLAG_TX_TIMESTAMP_NAME, NULL);
1016 		if (ret < 0)
1017 			return 0;
1018 	}
1019 	ret = pthread_mutex_lock(&sh->txpp.mutex);
1020 	MLX5_ASSERT(!ret);
1021 	RTE_SET_USED(ret);
1022 	if (sh->txpp.refcnt) {
1023 		priv->txpp_en = 1;
1024 		++sh->txpp.refcnt;
1025 	} else {
1026 		err = mlx5_txpp_create(sh, priv);
1027 		if (!err) {
1028 			MLX5_ASSERT(sh->txpp.tick);
1029 			priv->txpp_en = 1;
1030 			sh->txpp.refcnt = 1;
1031 		} else {
1032 			rte_errno = -err;
1033 		}
1034 	}
1035 	ret = pthread_mutex_unlock(&sh->txpp.mutex);
1036 	MLX5_ASSERT(!ret);
1037 	RTE_SET_USED(ret);
1038 	return err;
1039 }
1040 
1041 /**
1042  * Stops and destroys packet pacing infrastructure on specified device.
1043  *
1044  * @param dev
1045  *   Pointer to Ethernet device structure.
1046  *
1047  * @return
1048  *   0 on success, a negative errno value otherwise and rte_errno is set.
1049  */
1050 void
1051 mlx5_txpp_stop(struct rte_eth_dev *dev)
1052 {
1053 	struct mlx5_priv *priv = dev->data->dev_private;
1054 	struct mlx5_dev_ctx_shared *sh = priv->sh;
1055 	int ret;
1056 
1057 	if (!priv->txpp_en) {
1058 		/* Packet pacing is already disabled for the device. */
1059 		return;
1060 	}
1061 	priv->txpp_en = 0;
1062 	ret = pthread_mutex_lock(&sh->txpp.mutex);
1063 	MLX5_ASSERT(!ret);
1064 	RTE_SET_USED(ret);
1065 	MLX5_ASSERT(sh->txpp.refcnt);
1066 	if (!sh->txpp.refcnt || --sh->txpp.refcnt)
1067 		return;
1068 	/* No references any more, do actual destroy. */
1069 	mlx5_txpp_destroy(sh);
1070 	ret = pthread_mutex_unlock(&sh->txpp.mutex);
1071 	MLX5_ASSERT(!ret);
1072 	RTE_SET_USED(ret);
1073 }
1074 
1075 /*
1076  * Read the current clock counter of an Ethernet device
1077  *
1078  * This returns the current raw clock value of an Ethernet device. It is
1079  * a raw amount of ticks, with no given time reference.
1080  * The value returned here is from the same clock than the one
1081  * filling timestamp field of Rx/Tx packets when using hardware timestamp
1082  * offload. Therefore it can be used to compute a precise conversion of
1083  * the device clock to the real time.
1084  *
1085  * @param dev
1086  *   Pointer to Ethernet device structure.
1087  * @param clock
1088  *   Pointer to the uint64_t that holds the raw clock value.
1089  *
1090  * @return
1091  *   - 0: Success.
1092  *   - -ENOTSUP: The function is not supported in this mode. Requires
1093  *     packet pacing module configured and started (tx_pp devarg)
1094  */
1095 int
1096 mlx5_txpp_read_clock(struct rte_eth_dev *dev, uint64_t *timestamp)
1097 {
1098 	struct mlx5_priv *priv = dev->data->dev_private;
1099 	struct mlx5_dev_ctx_shared *sh = priv->sh;
1100 	int ret;
1101 
1102 	if (sh->txpp.refcnt) {
1103 		struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
1104 		struct mlx5_cqe *cqe = (struct mlx5_cqe *)(uintptr_t)wq->cqes;
1105 		union {
1106 			rte_int128_t u128;
1107 			struct mlx5_cqe_ts cts;
1108 		} to;
1109 		uint64_t ts;
1110 
1111 		mlx5_atomic_read_cqe((rte_int128_t *)&cqe->timestamp, &to.u128);
1112 		if (to.cts.op_own >> 4) {
1113 			DRV_LOG(DEBUG, "Clock Queue error sync lost.");
1114 			rte_atomic32_inc(&sh->txpp.err_clock_queue);
1115 			sh->txpp.sync_lost = 1;
1116 			return -EIO;
1117 		}
1118 		ts = rte_be_to_cpu_64(to.cts.timestamp);
1119 		ts = mlx5_txpp_convert_rx_ts(sh, ts);
1120 		*timestamp = ts;
1121 		return 0;
1122 	}
1123 	/* Not supported in isolated mode - kernel does not see the CQEs. */
1124 	if (priv->isolated || rte_eal_process_type() != RTE_PROC_PRIMARY)
1125 		return -ENOTSUP;
1126 	ret = mlx5_read_clock(dev, timestamp);
1127 	return ret;
1128 }
1129 
1130 /**
1131  * DPDK callback to clear device extended statistics.
1132  *
1133  * @param dev
1134  *   Pointer to Ethernet device structure.
1135  *
1136  * @return
1137  *   0 on success and stats is reset, negative errno value otherwise and
1138  *   rte_errno is set.
1139  */
1140 int mlx5_txpp_xstats_reset(struct rte_eth_dev *dev)
1141 {
1142 	struct mlx5_priv *priv = dev->data->dev_private;
1143 	struct mlx5_dev_ctx_shared *sh = priv->sh;
1144 
1145 	rte_atomic32_set(&sh->txpp.err_miss_int, 0);
1146 	rte_atomic32_set(&sh->txpp.err_rearm_queue, 0);
1147 	rte_atomic32_set(&sh->txpp.err_clock_queue, 0);
1148 	rte_atomic32_set(&sh->txpp.err_ts_past, 0);
1149 	rte_atomic32_set(&sh->txpp.err_ts_future, 0);
1150 	return 0;
1151 }
1152 
1153 /**
1154  * Routine to retrieve names of extended device statistics
1155  * for packet send scheduling. It appends the specific stats names
1156  * after the parts filled by preceding modules (eth stats, etc.)
1157  *
1158  * @param dev
1159  *   Pointer to Ethernet device structure.
1160  * @param[out] xstats_names
1161  *   Buffer to insert names into.
1162  * @param n
1163  *   Number of names.
1164  * @param n_used
1165  *   Number of names filled by preceding statistics modules.
1166  *
1167  * @return
1168  *   Number of xstats names.
1169  */
1170 int mlx5_txpp_xstats_get_names(struct rte_eth_dev *dev __rte_unused,
1171 			       struct rte_eth_xstat_name *xstats_names,
1172 			       unsigned int n, unsigned int n_used)
1173 {
1174 	unsigned int n_txpp = RTE_DIM(mlx5_txpp_stat_names);
1175 	unsigned int i;
1176 
1177 	if (n >= n_used + n_txpp && xstats_names) {
1178 		for (i = 0; i < n_txpp; ++i) {
1179 			strncpy(xstats_names[i + n_used].name,
1180 				mlx5_txpp_stat_names[i],
1181 				RTE_ETH_XSTATS_NAME_SIZE);
1182 			xstats_names[i + n_used].name
1183 					[RTE_ETH_XSTATS_NAME_SIZE - 1] = 0;
1184 		}
1185 	}
1186 	return n_used + n_txpp;
1187 }
1188 
1189 static inline void
1190 mlx5_txpp_read_tsa(struct mlx5_dev_txpp *txpp,
1191 		   struct mlx5_txpp_ts *tsa, uint16_t idx)
1192 {
1193 	do {
1194 		int64_t ts, ci;
1195 
1196 		ts = rte_atomic64_read(&txpp->tsa[idx].ts);
1197 		ci = rte_atomic64_read(&txpp->tsa[idx].ci_ts);
1198 		rte_compiler_barrier();
1199 		if ((ci ^ ts) << MLX5_CQ_INDEX_WIDTH != 0)
1200 			continue;
1201 		if (rte_atomic64_read(&txpp->tsa[idx].ts) != ts)
1202 			continue;
1203 		if (rte_atomic64_read(&txpp->tsa[idx].ci_ts) != ci)
1204 			continue;
1205 		rte_atomic64_set(&tsa->ts, ts);
1206 		rte_atomic64_set(&tsa->ci_ts, ci);
1207 		return;
1208 	} while (true);
1209 }
1210 
1211 /*
1212  * Jitter reflects the clock change between
1213  * neighbours Clock Queue completions.
1214  */
1215 static uint64_t
1216 mlx5_txpp_xstats_jitter(struct mlx5_dev_txpp *txpp)
1217 {
1218 	struct mlx5_txpp_ts tsa0, tsa1;
1219 	int64_t dts, dci;
1220 	uint16_t ts_p;
1221 
1222 	if (txpp->ts_n < 2) {
1223 		/* No gathered enough reports yet. */
1224 		return 0;
1225 	}
1226 	do {
1227 		int ts_0, ts_1;
1228 
1229 		ts_p = txpp->ts_p;
1230 		rte_compiler_barrier();
1231 		ts_0 = ts_p - 2;
1232 		if (ts_0 < 0)
1233 			ts_0 += MLX5_TXPP_REARM_SQ_SIZE;
1234 		ts_1 = ts_p - 1;
1235 		if (ts_1 < 0)
1236 			ts_1 += MLX5_TXPP_REARM_SQ_SIZE;
1237 		mlx5_txpp_read_tsa(txpp, &tsa0, ts_0);
1238 		mlx5_txpp_read_tsa(txpp, &tsa1, ts_1);
1239 		rte_compiler_barrier();
1240 	} while (ts_p != txpp->ts_p);
1241 	/* We have two neighbor reports, calculate the jitter. */
1242 	dts = rte_atomic64_read(&tsa1.ts) - rte_atomic64_read(&tsa0.ts);
1243 	dci = (rte_atomic64_read(&tsa1.ci_ts) >> (64 - MLX5_CQ_INDEX_WIDTH)) -
1244 	      (rte_atomic64_read(&tsa0.ci_ts) >> (64 - MLX5_CQ_INDEX_WIDTH));
1245 	if (dci < 0)
1246 		dci += 1 << MLX5_CQ_INDEX_WIDTH;
1247 	dci *= txpp->tick;
1248 	return (dts > dci) ? dts - dci : dci - dts;
1249 }
1250 
1251 /*
1252  * Wander reflects the long-term clock change
1253  * over the entire length of all Clock Queue completions.
1254  */
1255 static uint64_t
1256 mlx5_txpp_xstats_wander(struct mlx5_dev_txpp *txpp)
1257 {
1258 	struct mlx5_txpp_ts tsa0, tsa1;
1259 	int64_t dts, dci;
1260 	uint16_t ts_p;
1261 
1262 	if (txpp->ts_n < MLX5_TXPP_REARM_SQ_SIZE) {
1263 		/* No gathered enough reports yet. */
1264 		return 0;
1265 	}
1266 	do {
1267 		int ts_0, ts_1;
1268 
1269 		ts_p = txpp->ts_p;
1270 		rte_compiler_barrier();
1271 		ts_0 = ts_p - MLX5_TXPP_REARM_SQ_SIZE / 2 - 1;
1272 		if (ts_0 < 0)
1273 			ts_0 += MLX5_TXPP_REARM_SQ_SIZE;
1274 		ts_1 = ts_p - 1;
1275 		if (ts_1 < 0)
1276 			ts_1 += MLX5_TXPP_REARM_SQ_SIZE;
1277 		mlx5_txpp_read_tsa(txpp, &tsa0, ts_0);
1278 		mlx5_txpp_read_tsa(txpp, &tsa1, ts_1);
1279 		rte_compiler_barrier();
1280 	} while (ts_p != txpp->ts_p);
1281 	/* We have two neighbor reports, calculate the jitter. */
1282 	dts = rte_atomic64_read(&tsa1.ts) - rte_atomic64_read(&tsa0.ts);
1283 	dci = (rte_atomic64_read(&tsa1.ci_ts) >> (64 - MLX5_CQ_INDEX_WIDTH)) -
1284 	      (rte_atomic64_read(&tsa0.ci_ts) >> (64 - MLX5_CQ_INDEX_WIDTH));
1285 	dci += 1 << MLX5_CQ_INDEX_WIDTH;
1286 	dci *= txpp->tick;
1287 	return (dts > dci) ? dts - dci : dci - dts;
1288 }
1289 
1290 /**
1291  * Routine to retrieve extended device statistics
1292  * for packet send scheduling. It appends the specific statistics
1293  * after the parts filled by preceding modules (eth stats, etc.)
1294  *
1295  * @param dev
1296  *   Pointer to Ethernet device.
1297  * @param[out] stats
1298  *   Pointer to rte extended stats table.
1299  * @param n
1300  *   The size of the stats table.
1301  * @param n_used
1302  *   Number of stats filled by preceding statistics modules.
1303  *
1304  * @return
1305  *   Number of extended stats on success and stats is filled,
1306  *   negative on error and rte_errno is set.
1307  */
1308 int
1309 mlx5_txpp_xstats_get(struct rte_eth_dev *dev,
1310 		     struct rte_eth_xstat *stats,
1311 		     unsigned int n, unsigned int n_used)
1312 {
1313 	unsigned int n_txpp = RTE_DIM(mlx5_txpp_stat_names);
1314 
1315 	if (n >= n_used + n_txpp && stats) {
1316 		struct mlx5_priv *priv = dev->data->dev_private;
1317 		struct mlx5_dev_ctx_shared *sh = priv->sh;
1318 		unsigned int i;
1319 
1320 		for (i = 0; i < n_txpp; ++i)
1321 			stats[n_used + i].id = n_used + i;
1322 		stats[n_used + 0].value =
1323 				rte_atomic32_read(&sh->txpp.err_miss_int);
1324 		stats[n_used + 1].value =
1325 				rte_atomic32_read(&sh->txpp.err_rearm_queue);
1326 		stats[n_used + 2].value =
1327 				rte_atomic32_read(&sh->txpp.err_clock_queue);
1328 		stats[n_used + 3].value =
1329 				rte_atomic32_read(&sh->txpp.err_ts_past);
1330 		stats[n_used + 4].value =
1331 				rte_atomic32_read(&sh->txpp.err_ts_future);
1332 		stats[n_used + 5].value = mlx5_txpp_xstats_jitter(&sh->txpp);
1333 		stats[n_used + 6].value = mlx5_txpp_xstats_wander(&sh->txpp);
1334 		stats[n_used + 7].value = sh->txpp.sync_lost;
1335 	}
1336 	return n_used + n_txpp;
1337 }
1338