xref: /dpdk/drivers/net/mlx5/mlx5_txpp.c (revision 3bb3ebb51b789d4ecb417cbdb1dce5c7211f6f18)
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 <ethdev_driver.h>
9 #include <rte_interrupts.h>
10 #include <rte_alarm.h>
11 #include <rte_malloc.h>
12 #include <rte_cycles.h>
13 #include <rte_eal_paging.h>
14 
15 #include <mlx5_malloc.h>
16 #include <mlx5_common_devx.h>
17 
18 #include "mlx5.h"
19 #include "mlx5_rxtx.h"
20 #include "mlx5_common_os.h"
21 
22 static_assert(sizeof(struct mlx5_cqe_ts) == sizeof(rte_int128_t),
23 		"Wrong timestamp CQE part size");
24 
25 static const char * const mlx5_txpp_stat_names[] = {
26 	"tx_pp_missed_interrupt_errors", /* Missed service interrupt. */
27 	"tx_pp_rearm_queue_errors", /* Rearm Queue errors. */
28 	"tx_pp_clock_queue_errors", /* Clock Queue errors. */
29 	"tx_pp_timestamp_past_errors", /* Timestamp in the past. */
30 	"tx_pp_timestamp_future_errors", /* Timestamp in the distant future. */
31 	"tx_pp_jitter", /* Timestamp jitter (one Clock Queue completion). */
32 	"tx_pp_wander", /* Timestamp wander (half of Clock Queue CQEs). */
33 	"tx_pp_sync_lost", /* Scheduling synchronization lost. */
34 };
35 
36 /* Destroy Event Queue Notification Channel. */
37 static void
38 mlx5_txpp_destroy_event_channel(struct mlx5_dev_ctx_shared *sh)
39 {
40 	if (sh->txpp.echan) {
41 		mlx5_os_devx_destroy_event_channel(sh->txpp.echan);
42 		sh->txpp.echan = NULL;
43 	}
44 }
45 
46 /* Create Event Queue Notification Channel. */
47 static int
48 mlx5_txpp_create_event_channel(struct mlx5_dev_ctx_shared *sh)
49 {
50 	MLX5_ASSERT(!sh->txpp.echan);
51 	sh->txpp.echan = mlx5_os_devx_create_event_channel(sh->ctx,
52 			MLX5DV_DEVX_CREATE_EVENT_CHANNEL_FLAGS_OMIT_EV_DATA);
53 	if (!sh->txpp.echan) {
54 		rte_errno = errno;
55 		DRV_LOG(ERR, "Failed to create event channel %d.", rte_errno);
56 		return -rte_errno;
57 	}
58 	return 0;
59 }
60 
61 static void
62 mlx5_txpp_free_pp_index(struct mlx5_dev_ctx_shared *sh)
63 {
64 #ifdef HAVE_MLX5DV_PP_ALLOC
65 	if (sh->txpp.pp) {
66 		mlx5_glue->dv_free_pp(sh->txpp.pp);
67 		sh->txpp.pp = NULL;
68 		sh->txpp.pp_id = 0;
69 	}
70 #else
71 	RTE_SET_USED(sh);
72 	DRV_LOG(ERR, "Freeing pacing index is not supported.");
73 #endif
74 }
75 
76 /* Allocate Packet Pacing index from kernel via mlx5dv call. */
77 static int
78 mlx5_txpp_alloc_pp_index(struct mlx5_dev_ctx_shared *sh)
79 {
80 #ifdef HAVE_MLX5DV_PP_ALLOC
81 	uint32_t pp[MLX5_ST_SZ_DW(set_pp_rate_limit_context)];
82 	uint64_t rate;
83 
84 	MLX5_ASSERT(!sh->txpp.pp);
85 	memset(&pp, 0, sizeof(pp));
86 	rate = NS_PER_S / sh->txpp.tick;
87 	if (rate * sh->txpp.tick != NS_PER_S)
88 		DRV_LOG(WARNING, "Packet pacing frequency is not precise.");
89 	if (sh->txpp.test) {
90 		uint32_t len;
91 
92 		len = RTE_MAX(MLX5_TXPP_TEST_PKT_SIZE,
93 			      (size_t)RTE_ETHER_MIN_LEN);
94 		MLX5_SET(set_pp_rate_limit_context, &pp,
95 			 burst_upper_bound, len);
96 		MLX5_SET(set_pp_rate_limit_context, &pp,
97 			 typical_packet_size, len);
98 		/* Convert packets per second into kilobits. */
99 		rate = (rate * len) / (1000ul / CHAR_BIT);
100 		DRV_LOG(INFO, "Packet pacing rate set to %" PRIu64, rate);
101 	}
102 	MLX5_SET(set_pp_rate_limit_context, &pp, rate_limit, rate);
103 	MLX5_SET(set_pp_rate_limit_context, &pp, rate_mode,
104 		 sh->txpp.test ? MLX5_DATA_RATE : MLX5_WQE_RATE);
105 	sh->txpp.pp = mlx5_glue->dv_alloc_pp
106 				(sh->ctx, sizeof(pp), &pp,
107 				 MLX5DV_PP_ALLOC_FLAGS_DEDICATED_INDEX);
108 	if (sh->txpp.pp == NULL) {
109 		DRV_LOG(ERR, "Failed to allocate packet pacing index.");
110 		rte_errno = errno;
111 		return -errno;
112 	}
113 	if (!((struct mlx5dv_pp *)sh->txpp.pp)->index) {
114 		DRV_LOG(ERR, "Zero packet pacing index allocated.");
115 		mlx5_txpp_free_pp_index(sh);
116 		rte_errno = ENOTSUP;
117 		return -ENOTSUP;
118 	}
119 	sh->txpp.pp_id = ((struct mlx5dv_pp *)(sh->txpp.pp))->index;
120 	return 0;
121 #else
122 	RTE_SET_USED(sh);
123 	DRV_LOG(ERR, "Allocating pacing index is not supported.");
124 	rte_errno = ENOTSUP;
125 	return -ENOTSUP;
126 #endif
127 }
128 
129 static void
130 mlx5_txpp_destroy_send_queue(struct mlx5_txpp_wq *wq)
131 {
132 	mlx5_devx_sq_destroy(&wq->sq_obj);
133 	mlx5_devx_cq_destroy(&wq->cq_obj);
134 	memset(wq, 0, sizeof(*wq));
135 }
136 
137 static void
138 mlx5_txpp_destroy_rearm_queue(struct mlx5_dev_ctx_shared *sh)
139 {
140 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
141 
142 	mlx5_txpp_destroy_send_queue(wq);
143 }
144 
145 static void
146 mlx5_txpp_destroy_clock_queue(struct mlx5_dev_ctx_shared *sh)
147 {
148 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
149 
150 	mlx5_txpp_destroy_send_queue(wq);
151 	if (sh->txpp.tsa) {
152 		mlx5_free(sh->txpp.tsa);
153 		sh->txpp.tsa = NULL;
154 	}
155 }
156 
157 static void
158 mlx5_txpp_doorbell_rearm_queue(struct mlx5_dev_ctx_shared *sh, uint16_t ci)
159 {
160 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
161 	struct mlx5_wqe *wqe = (struct mlx5_wqe *)(uintptr_t)wq->sq_obj.wqes;
162 	union {
163 		uint32_t w32[2];
164 		uint64_t w64;
165 	} cs;
166 	void *reg_addr;
167 
168 	wq->sq_ci = ci + 1;
169 	cs.w32[0] = rte_cpu_to_be_32(rte_be_to_cpu_32
170 			(wqe[ci & (wq->sq_size - 1)].ctrl[0]) | (ci - 1) << 8);
171 	cs.w32[1] = wqe[ci & (wq->sq_size - 1)].ctrl[1];
172 	/* Update SQ doorbell record with new SQ ci. */
173 	rte_compiler_barrier();
174 	*wq->sq_obj.db_rec = rte_cpu_to_be_32(wq->sq_ci);
175 	/* Make sure the doorbell record is updated. */
176 	rte_wmb();
177 	/* Write to doorbel register to start processing. */
178 	reg_addr = mlx5_os_get_devx_uar_reg_addr(sh->tx_uar);
179 	__mlx5_uar_write64_relaxed(cs.w64, reg_addr, NULL);
180 	rte_wmb();
181 }
182 
183 static void
184 mlx5_txpp_fill_wqe_rearm_queue(struct mlx5_dev_ctx_shared *sh)
185 {
186 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
187 	struct mlx5_wqe *wqe = (struct mlx5_wqe *)(uintptr_t)wq->sq_obj.wqes;
188 	uint32_t i;
189 
190 	for (i = 0; i < wq->sq_size; i += 2) {
191 		struct mlx5_wqe_cseg *cs;
192 		struct mlx5_wqe_qseg *qs;
193 		uint32_t index;
194 
195 		/* Build SEND_EN request with slave WQE index. */
196 		cs = &wqe[i + 0].cseg;
197 		cs->opcode = RTE_BE32(MLX5_OPCODE_SEND_EN | 0);
198 		cs->sq_ds = rte_cpu_to_be_32((wq->sq_obj.sq->id << 8) | 2);
199 		cs->flags = RTE_BE32(MLX5_COMP_ALWAYS <<
200 				     MLX5_COMP_MODE_OFFSET);
201 		cs->misc = RTE_BE32(0);
202 		qs = RTE_PTR_ADD(cs, sizeof(struct mlx5_wqe_cseg));
203 		index = (i * MLX5_TXPP_REARM / 2 + MLX5_TXPP_REARM) &
204 			((1 << MLX5_WQ_INDEX_WIDTH) - 1);
205 		qs->max_index = rte_cpu_to_be_32(index);
206 		qs->qpn_cqn =
207 			   rte_cpu_to_be_32(sh->txpp.clock_queue.sq_obj.sq->id);
208 		/* Build WAIT request with slave CQE index. */
209 		cs = &wqe[i + 1].cseg;
210 		cs->opcode = RTE_BE32(MLX5_OPCODE_WAIT | 0);
211 		cs->sq_ds = rte_cpu_to_be_32((wq->sq_obj.sq->id << 8) | 2);
212 		cs->flags = RTE_BE32(MLX5_COMP_ONLY_ERR <<
213 				     MLX5_COMP_MODE_OFFSET);
214 		cs->misc = RTE_BE32(0);
215 		qs = RTE_PTR_ADD(cs, sizeof(struct mlx5_wqe_cseg));
216 		index = (i * MLX5_TXPP_REARM / 2 + MLX5_TXPP_REARM / 2) &
217 			((1 << MLX5_CQ_INDEX_WIDTH) - 1);
218 		qs->max_index = rte_cpu_to_be_32(index);
219 		qs->qpn_cqn =
220 			   rte_cpu_to_be_32(sh->txpp.clock_queue.cq_obj.cq->id);
221 	}
222 }
223 
224 /* Creates the Rearm Queue to fire the requests to Clock Queue in realtime. */
225 static int
226 mlx5_txpp_create_rearm_queue(struct mlx5_dev_ctx_shared *sh)
227 {
228 	struct mlx5_devx_create_sq_attr sq_attr = {
229 		.cd_master = 1,
230 		.state = MLX5_SQC_STATE_RST,
231 		.tis_lst_sz = 1,
232 		.tis_num = sh->tis->id,
233 		.wq_attr = (struct mlx5_devx_wq_attr){
234 			.pd = sh->pdn,
235 			.uar_page = mlx5_os_get_devx_uar_page_id(sh->tx_uar),
236 		},
237 		.ts_format = mlx5_ts_format_conv(sh->sq_ts_format),
238 	};
239 	struct mlx5_devx_modify_sq_attr msq_attr = { 0 };
240 	struct mlx5_devx_cq_attr cq_attr = {
241 		.uar_page_id = mlx5_os_get_devx_uar_page_id(sh->tx_uar),
242 	};
243 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
244 	int ret;
245 
246 	/* Create completion queue object for Rearm Queue. */
247 	ret = mlx5_devx_cq_create(sh->ctx, &wq->cq_obj,
248 				  log2above(MLX5_TXPP_REARM_CQ_SIZE), &cq_attr,
249 				  sh->numa_node);
250 	if (ret) {
251 		DRV_LOG(ERR, "Failed to create CQ for Rearm Queue.");
252 		return ret;
253 	}
254 	wq->cq_ci = 0;
255 	wq->arm_sn = 0;
256 	wq->sq_size = MLX5_TXPP_REARM_SQ_SIZE;
257 	MLX5_ASSERT(wq->sq_size == (1 << log2above(wq->sq_size)));
258 	/* Create send queue object for Rearm Queue. */
259 	sq_attr.cqn = wq->cq_obj.cq->id;
260 	/* There should be no WQE leftovers in the cyclic queue. */
261 	ret = mlx5_devx_sq_create(sh->ctx, &wq->sq_obj,
262 				  log2above(MLX5_TXPP_REARM_SQ_SIZE), &sq_attr,
263 				  sh->numa_node);
264 	if (ret) {
265 		rte_errno = errno;
266 		DRV_LOG(ERR, "Failed to create SQ for Rearm Queue.");
267 		goto error;
268 	}
269 	/* Build the WQEs in the Send Queue before goto Ready state. */
270 	mlx5_txpp_fill_wqe_rearm_queue(sh);
271 	/* Change queue state to ready. */
272 	msq_attr.sq_state = MLX5_SQC_STATE_RST;
273 	msq_attr.state = MLX5_SQC_STATE_RDY;
274 	ret = mlx5_devx_cmd_modify_sq(wq->sq_obj.sq, &msq_attr);
275 	if (ret) {
276 		DRV_LOG(ERR, "Failed to set SQ ready state Rearm Queue.");
277 		goto error;
278 	}
279 	return 0;
280 error:
281 	ret = -rte_errno;
282 	mlx5_txpp_destroy_rearm_queue(sh);
283 	rte_errno = -ret;
284 	return ret;
285 }
286 
287 static void
288 mlx5_txpp_fill_wqe_clock_queue(struct mlx5_dev_ctx_shared *sh)
289 {
290 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
291 	struct mlx5_wqe *wqe = (struct mlx5_wqe *)(uintptr_t)wq->sq_obj.wqes;
292 	struct mlx5_wqe_cseg *cs = &wqe->cseg;
293 	uint32_t wqe_size, opcode, i;
294 	uint8_t *dst;
295 
296 	/* For test purposes fill the WQ with SEND inline packet. */
297 	if (sh->txpp.test) {
298 		wqe_size = RTE_ALIGN(MLX5_TXPP_TEST_PKT_SIZE +
299 				     MLX5_WQE_CSEG_SIZE +
300 				     2 * MLX5_WQE_ESEG_SIZE -
301 				     MLX5_ESEG_MIN_INLINE_SIZE,
302 				     MLX5_WSEG_SIZE);
303 		opcode = MLX5_OPCODE_SEND;
304 	} else {
305 		wqe_size = MLX5_WSEG_SIZE;
306 		opcode = MLX5_OPCODE_NOP;
307 	}
308 	cs->opcode = rte_cpu_to_be_32(opcode | 0); /* Index is ignored. */
309 	cs->sq_ds = rte_cpu_to_be_32((wq->sq_obj.sq->id << 8) |
310 				     (wqe_size / MLX5_WSEG_SIZE));
311 	cs->flags = RTE_BE32(MLX5_COMP_ALWAYS << MLX5_COMP_MODE_OFFSET);
312 	cs->misc = RTE_BE32(0);
313 	wqe_size = RTE_ALIGN(wqe_size, MLX5_WQE_SIZE);
314 	if (sh->txpp.test) {
315 		struct mlx5_wqe_eseg *es = &wqe->eseg;
316 		struct rte_ether_hdr *eth_hdr;
317 		struct rte_ipv4_hdr *ip_hdr;
318 		struct rte_udp_hdr *udp_hdr;
319 
320 		/* Build the inline test packet pattern. */
321 		MLX5_ASSERT(wqe_size <= MLX5_WQE_SIZE_MAX);
322 		MLX5_ASSERT(MLX5_TXPP_TEST_PKT_SIZE >=
323 				(sizeof(struct rte_ether_hdr) +
324 				 sizeof(struct rte_ipv4_hdr)));
325 		es->flags = 0;
326 		es->cs_flags = MLX5_ETH_WQE_L3_CSUM | MLX5_ETH_WQE_L4_CSUM;
327 		es->swp_offs = 0;
328 		es->metadata = 0;
329 		es->swp_flags = 0;
330 		es->mss = 0;
331 		es->inline_hdr_sz = RTE_BE16(MLX5_TXPP_TEST_PKT_SIZE);
332 		/* Build test packet L2 header (Ethernet). */
333 		dst = (uint8_t *)&es->inline_data;
334 		eth_hdr = (struct rte_ether_hdr *)dst;
335 		rte_eth_random_addr(&eth_hdr->d_addr.addr_bytes[0]);
336 		rte_eth_random_addr(&eth_hdr->s_addr.addr_bytes[0]);
337 		eth_hdr->ether_type = rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4);
338 		/* Build test packet L3 header (IP v4). */
339 		dst += sizeof(struct rte_ether_hdr);
340 		ip_hdr = (struct rte_ipv4_hdr *)dst;
341 		ip_hdr->version_ihl = RTE_IPV4_VHL_DEF;
342 		ip_hdr->type_of_service = 0;
343 		ip_hdr->fragment_offset = 0;
344 		ip_hdr->time_to_live = 64;
345 		ip_hdr->next_proto_id = IPPROTO_UDP;
346 		ip_hdr->packet_id = 0;
347 		ip_hdr->total_length = RTE_BE16(MLX5_TXPP_TEST_PKT_SIZE -
348 						sizeof(struct rte_ether_hdr));
349 		/* use RFC5735 / RFC2544 reserved network test addresses */
350 		ip_hdr->src_addr = RTE_BE32((198U << 24) | (18 << 16) |
351 					    (0 << 8) | 1);
352 		ip_hdr->dst_addr = RTE_BE32((198U << 24) | (18 << 16) |
353 					    (0 << 8) | 2);
354 		if (MLX5_TXPP_TEST_PKT_SIZE <
355 					(sizeof(struct rte_ether_hdr) +
356 					 sizeof(struct rte_ipv4_hdr) +
357 					 sizeof(struct rte_udp_hdr)))
358 			goto wcopy;
359 		/* Build test packet L4 header (UDP). */
360 		dst += sizeof(struct rte_ipv4_hdr);
361 		udp_hdr = (struct rte_udp_hdr *)dst;
362 		udp_hdr->src_port = RTE_BE16(9); /* RFC863 Discard. */
363 		udp_hdr->dst_port = RTE_BE16(9);
364 		udp_hdr->dgram_len = RTE_BE16(MLX5_TXPP_TEST_PKT_SIZE -
365 					      sizeof(struct rte_ether_hdr) -
366 					      sizeof(struct rte_ipv4_hdr));
367 		udp_hdr->dgram_cksum = 0;
368 		/* Fill the test packet data. */
369 		dst += sizeof(struct rte_udp_hdr);
370 		for (i = sizeof(struct rte_ether_hdr) +
371 			sizeof(struct rte_ipv4_hdr) +
372 			sizeof(struct rte_udp_hdr);
373 				i < MLX5_TXPP_TEST_PKT_SIZE; i++)
374 			*dst++ = (uint8_t)(i & 0xFF);
375 	}
376 wcopy:
377 	/* Duplicate the pattern to the next WQEs. */
378 	dst = (uint8_t *)(uintptr_t)wq->sq_obj.umem_buf;
379 	for (i = 1; i < MLX5_TXPP_CLKQ_SIZE; i++) {
380 		dst += wqe_size;
381 		rte_memcpy(dst, (void *)(uintptr_t)wq->sq_obj.umem_buf,
382 			   wqe_size);
383 	}
384 }
385 
386 /* Creates the Clock Queue for packet pacing, returns zero on success. */
387 static int
388 mlx5_txpp_create_clock_queue(struct mlx5_dev_ctx_shared *sh)
389 {
390 	struct mlx5_devx_create_sq_attr sq_attr = { 0 };
391 	struct mlx5_devx_modify_sq_attr msq_attr = { 0 };
392 	struct mlx5_devx_cq_attr cq_attr = {
393 		.use_first_only = 1,
394 		.overrun_ignore = 1,
395 		.uar_page_id = mlx5_os_get_devx_uar_page_id(sh->tx_uar),
396 	};
397 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
398 	int ret;
399 
400 	sh->txpp.tsa = mlx5_malloc(MLX5_MEM_RTE | MLX5_MEM_ZERO,
401 				   MLX5_TXPP_REARM_SQ_SIZE *
402 				   sizeof(struct mlx5_txpp_ts),
403 				   0, sh->numa_node);
404 	if (!sh->txpp.tsa) {
405 		DRV_LOG(ERR, "Failed to allocate memory for CQ stats.");
406 		return -ENOMEM;
407 	}
408 	sh->txpp.ts_p = 0;
409 	sh->txpp.ts_n = 0;
410 	/* Create completion queue object for Clock Queue. */
411 	ret = mlx5_devx_cq_create(sh->ctx, &wq->cq_obj,
412 				  log2above(MLX5_TXPP_CLKQ_SIZE), &cq_attr,
413 				  sh->numa_node);
414 	if (ret) {
415 		DRV_LOG(ERR, "Failed to create CQ for Clock Queue.");
416 		goto error;
417 	}
418 	wq->cq_ci = 0;
419 	/* Allocate memory buffer for Send Queue WQEs. */
420 	if (sh->txpp.test) {
421 		wq->sq_size = RTE_ALIGN(MLX5_TXPP_TEST_PKT_SIZE +
422 					MLX5_WQE_CSEG_SIZE +
423 					2 * MLX5_WQE_ESEG_SIZE -
424 					MLX5_ESEG_MIN_INLINE_SIZE,
425 					MLX5_WQE_SIZE) / MLX5_WQE_SIZE;
426 		wq->sq_size *= MLX5_TXPP_CLKQ_SIZE;
427 	} else {
428 		wq->sq_size = MLX5_TXPP_CLKQ_SIZE;
429 	}
430 	/* There should not be WQE leftovers in the cyclic queue. */
431 	MLX5_ASSERT(wq->sq_size == (1 << log2above(wq->sq_size)));
432 	/* Create send queue object for Clock Queue. */
433 	if (sh->txpp.test) {
434 		sq_attr.tis_lst_sz = 1;
435 		sq_attr.tis_num = sh->tis->id;
436 		sq_attr.non_wire = 0;
437 		sq_attr.static_sq_wq = 1;
438 	} else {
439 		sq_attr.non_wire = 1;
440 		sq_attr.static_sq_wq = 1;
441 	}
442 	sq_attr.cqn = wq->cq_obj.cq->id;
443 	sq_attr.packet_pacing_rate_limit_index = sh->txpp.pp_id;
444 	sq_attr.wq_attr.cd_slave = 1;
445 	sq_attr.wq_attr.uar_page = mlx5_os_get_devx_uar_page_id(sh->tx_uar);
446 	sq_attr.wq_attr.pd = sh->pdn;
447 	sq_attr.ts_format = mlx5_ts_format_conv(sh->sq_ts_format);
448 	ret = mlx5_devx_sq_create(sh->ctx, &wq->sq_obj, log2above(wq->sq_size),
449 				  &sq_attr, sh->numa_node);
450 	if (ret) {
451 		rte_errno = errno;
452 		DRV_LOG(ERR, "Failed to create SQ for Clock Queue.");
453 		goto error;
454 	}
455 	/* Build the WQEs in the Send Queue before goto Ready state. */
456 	mlx5_txpp_fill_wqe_clock_queue(sh);
457 	/* Change queue state to ready. */
458 	msq_attr.sq_state = MLX5_SQC_STATE_RST;
459 	msq_attr.state = MLX5_SQC_STATE_RDY;
460 	wq->sq_ci = 0;
461 	ret = mlx5_devx_cmd_modify_sq(wq->sq_obj.sq, &msq_attr);
462 	if (ret) {
463 		DRV_LOG(ERR, "Failed to set SQ ready state Clock Queue.");
464 		goto error;
465 	}
466 	return 0;
467 error:
468 	ret = -rte_errno;
469 	mlx5_txpp_destroy_clock_queue(sh);
470 	rte_errno = -ret;
471 	return ret;
472 }
473 
474 /* Enable notification from the Rearm Queue CQ. */
475 static inline void
476 mlx5_txpp_cq_arm(struct mlx5_dev_ctx_shared *sh)
477 {
478 	void *base_addr;
479 
480 	struct mlx5_txpp_wq *aq = &sh->txpp.rearm_queue;
481 	uint32_t arm_sn = aq->arm_sn << MLX5_CQ_SQN_OFFSET;
482 	uint32_t db_hi = arm_sn | MLX5_CQ_DBR_CMD_ALL | aq->cq_ci;
483 	uint64_t db_be =
484 		rte_cpu_to_be_64(((uint64_t)db_hi << 32) | aq->cq_obj.cq->id);
485 	base_addr = mlx5_os_get_devx_uar_base_addr(sh->tx_uar);
486 	uint32_t *addr = RTE_PTR_ADD(base_addr, MLX5_CQ_DOORBELL);
487 
488 	rte_compiler_barrier();
489 	aq->cq_obj.db_rec[MLX5_CQ_ARM_DB] = rte_cpu_to_be_32(db_hi);
490 	rte_wmb();
491 #ifdef RTE_ARCH_64
492 	*(uint64_t *)addr = db_be;
493 #else
494 	*(uint32_t *)addr = db_be;
495 	rte_io_wmb();
496 	*((uint32_t *)addr + 1) = db_be >> 32;
497 #endif
498 	aq->arm_sn++;
499 }
500 
501 #if defined(RTE_ARCH_X86_64)
502 static inline int
503 mlx5_atomic128_compare_exchange(rte_int128_t *dst,
504 				rte_int128_t *exp,
505 				const rte_int128_t *src)
506 {
507 	uint8_t res;
508 
509 	asm volatile (MPLOCKED
510 		      "cmpxchg16b %[dst];"
511 		      " sete %[res]"
512 		      : [dst] "=m" (dst->val[0]),
513 			"=a" (exp->val[0]),
514 			"=d" (exp->val[1]),
515 			[res] "=r" (res)
516 		      : "b" (src->val[0]),
517 			"c" (src->val[1]),
518 			"a" (exp->val[0]),
519 			"d" (exp->val[1]),
520 			"m" (dst->val[0])
521 		      : "memory");
522 
523 	return res;
524 }
525 #endif
526 
527 static inline void
528 mlx5_atomic_read_cqe(rte_int128_t *from, rte_int128_t *ts)
529 {
530 	/*
531 	 * The only CQE of Clock Queue is being continuously
532 	 * update by hardware with soecified rate. We have to
533 	 * read timestump and WQE completion index atomically.
534 	 */
535 #if defined(RTE_ARCH_X86_64)
536 	rte_int128_t src;
537 
538 	memset(&src, 0, sizeof(src));
539 	*ts = src;
540 	/* if (*from == *ts) *from = *src else *ts = *from; */
541 	mlx5_atomic128_compare_exchange(from, ts, &src);
542 #else
543 	uint64_t *cqe = (uint64_t *)from;
544 
545 	/*
546 	 * Power architecture does not support 16B compare-and-swap.
547 	 * ARM implements it in software, code below is more relevant.
548 	 */
549 	for (;;) {
550 		uint64_t tm, op;
551 		uint64_t *ps;
552 
553 		rte_compiler_barrier();
554 		tm = __atomic_load_n(cqe + 0, __ATOMIC_RELAXED);
555 		op = __atomic_load_n(cqe + 1, __ATOMIC_RELAXED);
556 		rte_compiler_barrier();
557 		if (tm != __atomic_load_n(cqe + 0, __ATOMIC_RELAXED))
558 			continue;
559 		if (op != __atomic_load_n(cqe + 1, __ATOMIC_RELAXED))
560 			continue;
561 		ps = (uint64_t *)ts;
562 		ps[0] = tm;
563 		ps[1] = op;
564 		return;
565 	}
566 #endif
567 }
568 
569 /* Stores timestamp in the cache structure to share data with datapath. */
570 static inline void
571 mlx5_txpp_cache_timestamp(struct mlx5_dev_ctx_shared *sh,
572 			   uint64_t ts, uint64_t ci)
573 {
574 	ci = ci << (64 - MLX5_CQ_INDEX_WIDTH);
575 	ci |= (ts << MLX5_CQ_INDEX_WIDTH) >> MLX5_CQ_INDEX_WIDTH;
576 	rte_compiler_barrier();
577 	__atomic_store_n(&sh->txpp.ts.ts, ts, __ATOMIC_RELAXED);
578 	__atomic_store_n(&sh->txpp.ts.ci_ts, ci, __ATOMIC_RELAXED);
579 	rte_wmb();
580 }
581 
582 /* Reads timestamp from Clock Queue CQE and stores in the cache. */
583 static inline void
584 mlx5_txpp_update_timestamp(struct mlx5_dev_ctx_shared *sh)
585 {
586 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
587 	struct mlx5_cqe *cqe = (struct mlx5_cqe *)(uintptr_t)wq->cq_obj.cqes;
588 	union {
589 		rte_int128_t u128;
590 		struct mlx5_cqe_ts cts;
591 	} to;
592 	uint64_t ts;
593 	uint16_t ci;
594 
595 	mlx5_atomic_read_cqe((rte_int128_t *)&cqe->timestamp, &to.u128);
596 	if (to.cts.op_own >> 4) {
597 		DRV_LOG(DEBUG, "Clock Queue error sync lost.");
598 		__atomic_fetch_add(&sh->txpp.err_clock_queue,
599 				   1, __ATOMIC_RELAXED);
600 		sh->txpp.sync_lost = 1;
601 		return;
602 	}
603 	ci = rte_be_to_cpu_16(to.cts.wqe_counter);
604 	ts = rte_be_to_cpu_64(to.cts.timestamp);
605 	ts = mlx5_txpp_convert_rx_ts(sh, ts);
606 	wq->cq_ci += (ci - wq->sq_ci) & UINT16_MAX;
607 	wq->sq_ci = ci;
608 	mlx5_txpp_cache_timestamp(sh, ts, wq->cq_ci);
609 }
610 
611 /* Waits for the first completion on Clock Queue to init timestamp. */
612 static inline void
613 mlx5_txpp_init_timestamp(struct mlx5_dev_ctx_shared *sh)
614 {
615 	struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
616 	uint32_t wait;
617 
618 	sh->txpp.ts_p = 0;
619 	sh->txpp.ts_n = 0;
620 	for (wait = 0; wait < MLX5_TXPP_WAIT_INIT_TS; wait++) {
621 		mlx5_txpp_update_timestamp(sh);
622 		if (wq->sq_ci)
623 			return;
624 		/* Wait one millisecond and try again. */
625 		rte_delay_us_sleep(US_PER_S / MS_PER_S);
626 	}
627 	DRV_LOG(ERR, "Unable to initialize timestamp.");
628 	sh->txpp.sync_lost = 1;
629 }
630 
631 #ifdef HAVE_IBV_DEVX_EVENT
632 /* Gather statistics for timestamp from Clock Queue CQE. */
633 static inline void
634 mlx5_txpp_gather_timestamp(struct mlx5_dev_ctx_shared *sh)
635 {
636 	/* Check whether we have a valid timestamp. */
637 	if (!sh->txpp.clock_queue.sq_ci && !sh->txpp.ts_n)
638 		return;
639 	MLX5_ASSERT(sh->txpp.ts_p < MLX5_TXPP_REARM_SQ_SIZE);
640 	__atomic_store_n(&sh->txpp.tsa[sh->txpp.ts_p].ts,
641 			 sh->txpp.ts.ts, __ATOMIC_RELAXED);
642 	__atomic_store_n(&sh->txpp.tsa[sh->txpp.ts_p].ci_ts,
643 			 sh->txpp.ts.ci_ts, __ATOMIC_RELAXED);
644 	if (++sh->txpp.ts_p >= MLX5_TXPP_REARM_SQ_SIZE)
645 		sh->txpp.ts_p = 0;
646 	if (sh->txpp.ts_n < MLX5_TXPP_REARM_SQ_SIZE)
647 		++sh->txpp.ts_n;
648 }
649 
650 /* Handles Rearm Queue completions in periodic service. */
651 static __rte_always_inline void
652 mlx5_txpp_handle_rearm_queue(struct mlx5_dev_ctx_shared *sh)
653 {
654 	struct mlx5_txpp_wq *wq = &sh->txpp.rearm_queue;
655 	uint32_t cq_ci = wq->cq_ci;
656 	bool error = false;
657 	int ret;
658 
659 	do {
660 		volatile struct mlx5_cqe *cqe;
661 
662 		cqe = &wq->cq_obj.cqes[cq_ci & (MLX5_TXPP_REARM_CQ_SIZE - 1)];
663 		ret = check_cqe(cqe, MLX5_TXPP_REARM_CQ_SIZE, cq_ci);
664 		switch (ret) {
665 		case MLX5_CQE_STATUS_ERR:
666 			error = true;
667 			++cq_ci;
668 			break;
669 		case MLX5_CQE_STATUS_SW_OWN:
670 			wq->sq_ci += 2;
671 			++cq_ci;
672 			break;
673 		case MLX5_CQE_STATUS_HW_OWN:
674 			break;
675 		default:
676 			MLX5_ASSERT(false);
677 			break;
678 		}
679 	} while (ret != MLX5_CQE_STATUS_HW_OWN);
680 	if (likely(cq_ci != wq->cq_ci)) {
681 		/* Check whether we have missed interrupts. */
682 		if (cq_ci - wq->cq_ci != 1) {
683 			DRV_LOG(DEBUG, "Rearm Queue missed interrupt.");
684 			__atomic_fetch_add(&sh->txpp.err_miss_int,
685 					   1, __ATOMIC_RELAXED);
686 			/* Check sync lost on wqe index. */
687 			if (cq_ci - wq->cq_ci >=
688 				(((1UL << MLX5_WQ_INDEX_WIDTH) /
689 				  MLX5_TXPP_REARM) - 1))
690 				error = 1;
691 		}
692 		/* Update doorbell record to notify hardware. */
693 		rte_compiler_barrier();
694 		*wq->cq_obj.db_rec = rte_cpu_to_be_32(cq_ci);
695 		rte_wmb();
696 		wq->cq_ci = cq_ci;
697 		/* Fire new requests to Rearm Queue. */
698 		if (error) {
699 			DRV_LOG(DEBUG, "Rearm Queue error sync lost.");
700 			__atomic_fetch_add(&sh->txpp.err_rearm_queue,
701 					   1, __ATOMIC_RELAXED);
702 			sh->txpp.sync_lost = 1;
703 		}
704 	}
705 }
706 
707 /* Handles Clock Queue completions in periodic service. */
708 static __rte_always_inline void
709 mlx5_txpp_handle_clock_queue(struct mlx5_dev_ctx_shared *sh)
710 {
711 	mlx5_txpp_update_timestamp(sh);
712 	mlx5_txpp_gather_timestamp(sh);
713 }
714 #endif
715 
716 /* Invoked periodically on Rearm Queue completions. */
717 void
718 mlx5_txpp_interrupt_handler(void *cb_arg)
719 {
720 #ifndef HAVE_IBV_DEVX_EVENT
721 	RTE_SET_USED(cb_arg);
722 	return;
723 #else
724 	struct mlx5_dev_ctx_shared *sh = cb_arg;
725 	union {
726 		struct mlx5dv_devx_async_event_hdr event_resp;
727 		uint8_t buf[sizeof(struct mlx5dv_devx_async_event_hdr) + 128];
728 	} out;
729 
730 	MLX5_ASSERT(rte_eal_process_type() == RTE_PROC_PRIMARY);
731 	/* Process events in the loop. Only rearm completions are expected. */
732 	while (mlx5_glue->devx_get_event
733 				(sh->txpp.echan,
734 				 &out.event_resp,
735 				 sizeof(out.buf)) >=
736 				 (ssize_t)sizeof(out.event_resp.cookie)) {
737 		mlx5_txpp_handle_rearm_queue(sh);
738 		mlx5_txpp_handle_clock_queue(sh);
739 		mlx5_txpp_cq_arm(sh);
740 		mlx5_txpp_doorbell_rearm_queue
741 					(sh, sh->txpp.rearm_queue.sq_ci - 1);
742 	}
743 #endif /* HAVE_IBV_DEVX_ASYNC */
744 }
745 
746 static void
747 mlx5_txpp_stop_service(struct mlx5_dev_ctx_shared *sh)
748 {
749 	if (!sh->txpp.intr_handle.fd)
750 		return;
751 	mlx5_intr_callback_unregister(&sh->txpp.intr_handle,
752 				      mlx5_txpp_interrupt_handler, sh);
753 	sh->txpp.intr_handle.fd = 0;
754 }
755 
756 /* Attach interrupt handler and fires first request to Rearm Queue. */
757 static int
758 mlx5_txpp_start_service(struct mlx5_dev_ctx_shared *sh)
759 {
760 	uint16_t event_nums[1] = {0};
761 	int ret;
762 	int fd;
763 
764 	sh->txpp.err_miss_int = 0;
765 	sh->txpp.err_rearm_queue = 0;
766 	sh->txpp.err_clock_queue = 0;
767 	sh->txpp.err_ts_past = 0;
768 	sh->txpp.err_ts_future = 0;
769 	/* Attach interrupt handler to process Rearm Queue completions. */
770 	fd = mlx5_os_get_devx_channel_fd(sh->txpp.echan);
771 	ret = mlx5_os_set_nonblock_channel_fd(fd);
772 	if (ret) {
773 		DRV_LOG(ERR, "Failed to change event channel FD.");
774 		rte_errno = errno;
775 		return -rte_errno;
776 	}
777 	memset(&sh->txpp.intr_handle, 0, sizeof(sh->txpp.intr_handle));
778 	fd = mlx5_os_get_devx_channel_fd(sh->txpp.echan);
779 	sh->txpp.intr_handle.fd = fd;
780 	sh->txpp.intr_handle.type = RTE_INTR_HANDLE_EXT;
781 	if (rte_intr_callback_register(&sh->txpp.intr_handle,
782 				       mlx5_txpp_interrupt_handler, sh)) {
783 		sh->txpp.intr_handle.fd = 0;
784 		DRV_LOG(ERR, "Failed to register CQE interrupt %d.", rte_errno);
785 		return -rte_errno;
786 	}
787 	/* Subscribe CQ event to the event channel controlled by the driver. */
788 	ret = mlx5_os_devx_subscribe_devx_event(sh->txpp.echan,
789 					    sh->txpp.rearm_queue.cq_obj.cq->obj,
790 					     sizeof(event_nums), event_nums, 0);
791 	if (ret) {
792 		DRV_LOG(ERR, "Failed to subscribe CQE event.");
793 		rte_errno = errno;
794 		return -errno;
795 	}
796 	/* Enable interrupts in the CQ. */
797 	mlx5_txpp_cq_arm(sh);
798 	/* Fire the first request on Rearm Queue. */
799 	mlx5_txpp_doorbell_rearm_queue(sh, sh->txpp.rearm_queue.sq_size - 1);
800 	mlx5_txpp_init_timestamp(sh);
801 	return 0;
802 }
803 
804 /*
805  * The routine initializes the packet pacing infrastructure:
806  * - allocates PP context
807  * - Clock CQ/SQ
808  * - Rearm CQ/SQ
809  * - attaches rearm interrupt handler
810  * - starts Clock Queue
811  *
812  * Returns 0 on success, negative otherwise
813  */
814 static int
815 mlx5_txpp_create(struct mlx5_dev_ctx_shared *sh, struct mlx5_priv *priv)
816 {
817 	int tx_pp = priv->config.tx_pp;
818 	int ret;
819 
820 	/* Store the requested pacing parameters. */
821 	sh->txpp.tick = tx_pp >= 0 ? tx_pp : -tx_pp;
822 	sh->txpp.test = !!(tx_pp < 0);
823 	sh->txpp.skew = priv->config.tx_skew;
824 	sh->txpp.freq = priv->config.hca_attr.dev_freq_khz;
825 	ret = mlx5_txpp_create_event_channel(sh);
826 	if (ret)
827 		goto exit;
828 	ret = mlx5_txpp_alloc_pp_index(sh);
829 	if (ret)
830 		goto exit;
831 	ret = mlx5_txpp_create_clock_queue(sh);
832 	if (ret)
833 		goto exit;
834 	ret = mlx5_txpp_create_rearm_queue(sh);
835 	if (ret)
836 		goto exit;
837 	ret = mlx5_txpp_start_service(sh);
838 	if (ret)
839 		goto exit;
840 exit:
841 	if (ret) {
842 		mlx5_txpp_stop_service(sh);
843 		mlx5_txpp_destroy_rearm_queue(sh);
844 		mlx5_txpp_destroy_clock_queue(sh);
845 		mlx5_txpp_free_pp_index(sh);
846 		mlx5_txpp_destroy_event_channel(sh);
847 		sh->txpp.tick = 0;
848 		sh->txpp.test = 0;
849 		sh->txpp.skew = 0;
850 	}
851 	return ret;
852 }
853 
854 /*
855  * The routine destroys the packet pacing infrastructure:
856  * - detaches rearm interrupt handler
857  * - Rearm CQ/SQ
858  * - Clock CQ/SQ
859  * - PP context
860  */
861 static void
862 mlx5_txpp_destroy(struct mlx5_dev_ctx_shared *sh)
863 {
864 	mlx5_txpp_stop_service(sh);
865 	mlx5_txpp_destroy_rearm_queue(sh);
866 	mlx5_txpp_destroy_clock_queue(sh);
867 	mlx5_txpp_free_pp_index(sh);
868 	mlx5_txpp_destroy_event_channel(sh);
869 	sh->txpp.tick = 0;
870 	sh->txpp.test = 0;
871 	sh->txpp.skew = 0;
872 }
873 
874 /**
875  * Creates and starts packet pacing infrastructure on specified device.
876  *
877  * @param dev
878  *   Pointer to Ethernet device structure.
879  *
880  * @return
881  *   0 on success, a negative errno value otherwise and rte_errno is set.
882  */
883 int
884 mlx5_txpp_start(struct rte_eth_dev *dev)
885 {
886 	struct mlx5_priv *priv = dev->data->dev_private;
887 	struct mlx5_dev_ctx_shared *sh = priv->sh;
888 	int err = 0;
889 	int ret;
890 
891 	if (!priv->config.tx_pp) {
892 		/* Packet pacing is not requested for the device. */
893 		MLX5_ASSERT(priv->txpp_en == 0);
894 		return 0;
895 	}
896 	if (priv->txpp_en) {
897 		/* Packet pacing is already enabled for the device. */
898 		MLX5_ASSERT(sh->txpp.refcnt);
899 		return 0;
900 	}
901 	if (priv->config.tx_pp > 0) {
902 		ret = rte_mbuf_dynflag_lookup
903 				(RTE_MBUF_DYNFLAG_TX_TIMESTAMP_NAME, NULL);
904 		if (ret < 0)
905 			return 0;
906 	}
907 	ret = pthread_mutex_lock(&sh->txpp.mutex);
908 	MLX5_ASSERT(!ret);
909 	RTE_SET_USED(ret);
910 	if (sh->txpp.refcnt) {
911 		priv->txpp_en = 1;
912 		++sh->txpp.refcnt;
913 	} else {
914 		err = mlx5_txpp_create(sh, priv);
915 		if (!err) {
916 			MLX5_ASSERT(sh->txpp.tick);
917 			priv->txpp_en = 1;
918 			sh->txpp.refcnt = 1;
919 		} else {
920 			rte_errno = -err;
921 		}
922 	}
923 	ret = pthread_mutex_unlock(&sh->txpp.mutex);
924 	MLX5_ASSERT(!ret);
925 	RTE_SET_USED(ret);
926 	return err;
927 }
928 
929 /**
930  * Stops and destroys packet pacing infrastructure on specified device.
931  *
932  * @param dev
933  *   Pointer to Ethernet device structure.
934  *
935  * @return
936  *   0 on success, a negative errno value otherwise and rte_errno is set.
937  */
938 void
939 mlx5_txpp_stop(struct rte_eth_dev *dev)
940 {
941 	struct mlx5_priv *priv = dev->data->dev_private;
942 	struct mlx5_dev_ctx_shared *sh = priv->sh;
943 	int ret;
944 
945 	if (!priv->txpp_en) {
946 		/* Packet pacing is already disabled for the device. */
947 		return;
948 	}
949 	priv->txpp_en = 0;
950 	ret = pthread_mutex_lock(&sh->txpp.mutex);
951 	MLX5_ASSERT(!ret);
952 	RTE_SET_USED(ret);
953 	MLX5_ASSERT(sh->txpp.refcnt);
954 	if (!sh->txpp.refcnt || --sh->txpp.refcnt)
955 		return;
956 	/* No references any more, do actual destroy. */
957 	mlx5_txpp_destroy(sh);
958 	ret = pthread_mutex_unlock(&sh->txpp.mutex);
959 	MLX5_ASSERT(!ret);
960 	RTE_SET_USED(ret);
961 }
962 
963 /*
964  * Read the current clock counter of an Ethernet device
965  *
966  * This returns the current raw clock value of an Ethernet device. It is
967  * a raw amount of ticks, with no given time reference.
968  * The value returned here is from the same clock than the one
969  * filling timestamp field of Rx/Tx packets when using hardware timestamp
970  * offload. Therefore it can be used to compute a precise conversion of
971  * the device clock to the real time.
972  *
973  * @param dev
974  *   Pointer to Ethernet device structure.
975  * @param clock
976  *   Pointer to the uint64_t that holds the raw clock value.
977  *
978  * @return
979  *   - 0: Success.
980  *   - -ENOTSUP: The function is not supported in this mode. Requires
981  *     packet pacing module configured and started (tx_pp devarg)
982  */
983 int
984 mlx5_txpp_read_clock(struct rte_eth_dev *dev, uint64_t *timestamp)
985 {
986 	struct mlx5_priv *priv = dev->data->dev_private;
987 	struct mlx5_dev_ctx_shared *sh = priv->sh;
988 	int ret;
989 
990 	if (sh->txpp.refcnt) {
991 		struct mlx5_txpp_wq *wq = &sh->txpp.clock_queue;
992 		struct mlx5_cqe *cqe =
993 				(struct mlx5_cqe *)(uintptr_t)wq->cq_obj.cqes;
994 		union {
995 			rte_int128_t u128;
996 			struct mlx5_cqe_ts cts;
997 		} to;
998 		uint64_t ts;
999 
1000 		mlx5_atomic_read_cqe((rte_int128_t *)&cqe->timestamp, &to.u128);
1001 		if (to.cts.op_own >> 4) {
1002 			DRV_LOG(DEBUG, "Clock Queue error sync lost.");
1003 			__atomic_fetch_add(&sh->txpp.err_clock_queue,
1004 					   1, __ATOMIC_RELAXED);
1005 			sh->txpp.sync_lost = 1;
1006 			return -EIO;
1007 		}
1008 		ts = rte_be_to_cpu_64(to.cts.timestamp);
1009 		ts = mlx5_txpp_convert_rx_ts(sh, ts);
1010 		*timestamp = ts;
1011 		return 0;
1012 	}
1013 	/* Not supported in isolated mode - kernel does not see the CQEs. */
1014 	if (priv->isolated || rte_eal_process_type() != RTE_PROC_PRIMARY)
1015 		return -ENOTSUP;
1016 	ret = mlx5_read_clock(dev, timestamp);
1017 	return ret;
1018 }
1019 
1020 /**
1021  * DPDK callback to clear device extended statistics.
1022  *
1023  * @param dev
1024  *   Pointer to Ethernet device structure.
1025  *
1026  * @return
1027  *   0 on success and stats is reset, negative errno value otherwise and
1028  *   rte_errno is set.
1029  */
1030 int mlx5_txpp_xstats_reset(struct rte_eth_dev *dev)
1031 {
1032 	struct mlx5_priv *priv = dev->data->dev_private;
1033 	struct mlx5_dev_ctx_shared *sh = priv->sh;
1034 
1035 	__atomic_store_n(&sh->txpp.err_miss_int, 0, __ATOMIC_RELAXED);
1036 	__atomic_store_n(&sh->txpp.err_rearm_queue, 0, __ATOMIC_RELAXED);
1037 	__atomic_store_n(&sh->txpp.err_clock_queue, 0, __ATOMIC_RELAXED);
1038 	__atomic_store_n(&sh->txpp.err_ts_past, 0, __ATOMIC_RELAXED);
1039 	__atomic_store_n(&sh->txpp.err_ts_future, 0, __ATOMIC_RELAXED);
1040 	return 0;
1041 }
1042 
1043 /**
1044  * Routine to retrieve names of extended device statistics
1045  * for packet send scheduling. It appends the specific stats names
1046  * after the parts filled by preceding modules (eth stats, etc.)
1047  *
1048  * @param dev
1049  *   Pointer to Ethernet device structure.
1050  * @param[out] xstats_names
1051  *   Buffer to insert names into.
1052  * @param n
1053  *   Number of names.
1054  * @param n_used
1055  *   Number of names filled by preceding statistics modules.
1056  *
1057  * @return
1058  *   Number of xstats names.
1059  */
1060 int mlx5_txpp_xstats_get_names(struct rte_eth_dev *dev __rte_unused,
1061 			       struct rte_eth_xstat_name *xstats_names,
1062 			       unsigned int n, unsigned int n_used)
1063 {
1064 	unsigned int n_txpp = RTE_DIM(mlx5_txpp_stat_names);
1065 	unsigned int i;
1066 
1067 	if (n >= n_used + n_txpp && xstats_names) {
1068 		for (i = 0; i < n_txpp; ++i) {
1069 			strncpy(xstats_names[i + n_used].name,
1070 				mlx5_txpp_stat_names[i],
1071 				RTE_ETH_XSTATS_NAME_SIZE);
1072 			xstats_names[i + n_used].name
1073 					[RTE_ETH_XSTATS_NAME_SIZE - 1] = 0;
1074 		}
1075 	}
1076 	return n_used + n_txpp;
1077 }
1078 
1079 static inline void
1080 mlx5_txpp_read_tsa(struct mlx5_dev_txpp *txpp,
1081 		   struct mlx5_txpp_ts *tsa, uint16_t idx)
1082 {
1083 	do {
1084 		uint64_t ts, ci;
1085 
1086 		ts = __atomic_load_n(&txpp->tsa[idx].ts, __ATOMIC_RELAXED);
1087 		ci = __atomic_load_n(&txpp->tsa[idx].ci_ts, __ATOMIC_RELAXED);
1088 		rte_compiler_barrier();
1089 		if ((ci ^ ts) << MLX5_CQ_INDEX_WIDTH != 0)
1090 			continue;
1091 		if (__atomic_load_n(&txpp->tsa[idx].ts,
1092 				    __ATOMIC_RELAXED) != ts)
1093 			continue;
1094 		if (__atomic_load_n(&txpp->tsa[idx].ci_ts,
1095 				    __ATOMIC_RELAXED) != ci)
1096 			continue;
1097 		tsa->ts = ts;
1098 		tsa->ci_ts = ci;
1099 		return;
1100 	} while (true);
1101 }
1102 
1103 /*
1104  * Jitter reflects the clock change between
1105  * neighbours Clock Queue completions.
1106  */
1107 static uint64_t
1108 mlx5_txpp_xstats_jitter(struct mlx5_dev_txpp *txpp)
1109 {
1110 	struct mlx5_txpp_ts tsa0, tsa1;
1111 	int64_t dts, dci;
1112 	uint16_t ts_p;
1113 
1114 	if (txpp->ts_n < 2) {
1115 		/* No gathered enough reports yet. */
1116 		return 0;
1117 	}
1118 	do {
1119 		int ts_0, ts_1;
1120 
1121 		ts_p = txpp->ts_p;
1122 		rte_compiler_barrier();
1123 		ts_0 = ts_p - 2;
1124 		if (ts_0 < 0)
1125 			ts_0 += MLX5_TXPP_REARM_SQ_SIZE;
1126 		ts_1 = ts_p - 1;
1127 		if (ts_1 < 0)
1128 			ts_1 += MLX5_TXPP_REARM_SQ_SIZE;
1129 		mlx5_txpp_read_tsa(txpp, &tsa0, ts_0);
1130 		mlx5_txpp_read_tsa(txpp, &tsa1, ts_1);
1131 		rte_compiler_barrier();
1132 	} while (ts_p != txpp->ts_p);
1133 	/* We have two neighbor reports, calculate the jitter. */
1134 	dts = tsa1.ts - tsa0.ts;
1135 	dci = (tsa1.ci_ts >> (64 - MLX5_CQ_INDEX_WIDTH)) -
1136 	      (tsa0.ci_ts >> (64 - MLX5_CQ_INDEX_WIDTH));
1137 	if (dci < 0)
1138 		dci += 1 << MLX5_CQ_INDEX_WIDTH;
1139 	dci *= txpp->tick;
1140 	return (dts > dci) ? dts - dci : dci - dts;
1141 }
1142 
1143 /*
1144  * Wander reflects the long-term clock change
1145  * over the entire length of all Clock Queue completions.
1146  */
1147 static uint64_t
1148 mlx5_txpp_xstats_wander(struct mlx5_dev_txpp *txpp)
1149 {
1150 	struct mlx5_txpp_ts tsa0, tsa1;
1151 	int64_t dts, dci;
1152 	uint16_t ts_p;
1153 
1154 	if (txpp->ts_n < MLX5_TXPP_REARM_SQ_SIZE) {
1155 		/* No gathered enough reports yet. */
1156 		return 0;
1157 	}
1158 	do {
1159 		int ts_0, ts_1;
1160 
1161 		ts_p = txpp->ts_p;
1162 		rte_compiler_barrier();
1163 		ts_0 = ts_p - MLX5_TXPP_REARM_SQ_SIZE / 2 - 1;
1164 		if (ts_0 < 0)
1165 			ts_0 += MLX5_TXPP_REARM_SQ_SIZE;
1166 		ts_1 = ts_p - 1;
1167 		if (ts_1 < 0)
1168 			ts_1 += MLX5_TXPP_REARM_SQ_SIZE;
1169 		mlx5_txpp_read_tsa(txpp, &tsa0, ts_0);
1170 		mlx5_txpp_read_tsa(txpp, &tsa1, ts_1);
1171 		rte_compiler_barrier();
1172 	} while (ts_p != txpp->ts_p);
1173 	/* We have two neighbor reports, calculate the jitter. */
1174 	dts = tsa1.ts - tsa0.ts;
1175 	dci = (tsa1.ci_ts >> (64 - MLX5_CQ_INDEX_WIDTH)) -
1176 	      (tsa0.ci_ts >> (64 - MLX5_CQ_INDEX_WIDTH));
1177 	dci += 1 << MLX5_CQ_INDEX_WIDTH;
1178 	dci *= txpp->tick;
1179 	return (dts > dci) ? dts - dci : dci - dts;
1180 }
1181 
1182 /**
1183  * Routine to retrieve extended device statistics
1184  * for packet send scheduling. It appends the specific statistics
1185  * after the parts filled by preceding modules (eth stats, etc.)
1186  *
1187  * @param dev
1188  *   Pointer to Ethernet device.
1189  * @param[out] stats
1190  *   Pointer to rte extended stats table.
1191  * @param n
1192  *   The size of the stats table.
1193  * @param n_used
1194  *   Number of stats filled by preceding statistics modules.
1195  *
1196  * @return
1197  *   Number of extended stats on success and stats is filled,
1198  *   negative on error and rte_errno is set.
1199  */
1200 int
1201 mlx5_txpp_xstats_get(struct rte_eth_dev *dev,
1202 		     struct rte_eth_xstat *stats,
1203 		     unsigned int n, unsigned int n_used)
1204 {
1205 	unsigned int n_txpp = RTE_DIM(mlx5_txpp_stat_names);
1206 
1207 	if (n >= n_used + n_txpp && stats) {
1208 		struct mlx5_priv *priv = dev->data->dev_private;
1209 		struct mlx5_dev_ctx_shared *sh = priv->sh;
1210 		unsigned int i;
1211 
1212 		for (i = 0; i < n_txpp; ++i)
1213 			stats[n_used + i].id = n_used + i;
1214 		stats[n_used + 0].value =
1215 				__atomic_load_n(&sh->txpp.err_miss_int,
1216 						__ATOMIC_RELAXED);
1217 		stats[n_used + 1].value =
1218 				__atomic_load_n(&sh->txpp.err_rearm_queue,
1219 						__ATOMIC_RELAXED);
1220 		stats[n_used + 2].value =
1221 				__atomic_load_n(&sh->txpp.err_clock_queue,
1222 						__ATOMIC_RELAXED);
1223 		stats[n_used + 3].value =
1224 				__atomic_load_n(&sh->txpp.err_ts_past,
1225 						__ATOMIC_RELAXED);
1226 		stats[n_used + 4].value =
1227 				__atomic_load_n(&sh->txpp.err_ts_future,
1228 						__ATOMIC_RELAXED);
1229 		stats[n_used + 5].value = mlx5_txpp_xstats_jitter(&sh->txpp);
1230 		stats[n_used + 6].value = mlx5_txpp_xstats_wander(&sh->txpp);
1231 		stats[n_used + 7].value = sh->txpp.sync_lost;
1232 	}
1233 	return n_used + n_txpp;
1234 }
1235