xref: /linux/drivers/net/ethernet/microchip/sparx5/sparx5_qos.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0+
2 /* Microchip Sparx5 Switch driver
3  *
4  * Copyright (c) 2022 Microchip Technology Inc. and its subsidiaries.
5  */
6 
7 #include <net/pkt_cls.h>
8 
9 #include "sparx5_main.h"
10 #include "sparx5_qos.h"
11 
12 /* Calculate new base_time based on cycle_time.
13  *
14  * The hardware requires a base_time that is always in the future.
15  * We define threshold_time as current_time + (2 * cycle_time).
16  * If base_time is below threshold_time this function recalculates it to be in
17  * the interval:
18  * threshold_time <= base_time < (threshold_time + cycle_time)
19  *
20  * A very simple algorithm could be like this:
21  * new_base_time = org_base_time + N * cycle_time
22  * using the lowest N so (new_base_time >= threshold_time
23  */
24 void sparx5_new_base_time(struct sparx5 *sparx5, const u32 cycle_time,
25 			  const ktime_t org_base_time, ktime_t *new_base_time)
26 {
27 	ktime_t current_time, threshold_time, new_time;
28 	struct timespec64 ts;
29 	u64 nr_of_cycles_p2;
30 	u64 nr_of_cycles;
31 	u64 diff_time;
32 
33 	new_time = org_base_time;
34 
35 	sparx5_ptp_gettime64(&sparx5->phc[SPARX5_PHC_PORT].info, &ts);
36 	current_time = timespec64_to_ktime(ts);
37 	threshold_time = current_time + (2 * cycle_time);
38 	diff_time = threshold_time - new_time;
39 	nr_of_cycles = div_u64(diff_time, cycle_time);
40 	nr_of_cycles_p2 = 1; /* Use 2^0 as start value */
41 
42 	if (new_time >= threshold_time) {
43 		*new_base_time = new_time;
44 		return;
45 	}
46 
47 	/* Calculate the smallest power of 2 (nr_of_cycles_p2)
48 	 * that is larger than nr_of_cycles.
49 	 */
50 	while (nr_of_cycles_p2 < nr_of_cycles)
51 		nr_of_cycles_p2 <<= 1; /* Next (higher) power of 2 */
52 
53 	/* Add as big chunks (power of 2 * cycle_time)
54 	 * as possible for each power of 2
55 	 */
56 	while (nr_of_cycles_p2) {
57 		if (new_time < threshold_time) {
58 			new_time += cycle_time * nr_of_cycles_p2;
59 			while (new_time < threshold_time)
60 				new_time += cycle_time * nr_of_cycles_p2;
61 			new_time -= cycle_time * nr_of_cycles_p2;
62 		}
63 		nr_of_cycles_p2 >>= 1; /* Next (lower) power of 2 */
64 	}
65 	new_time += cycle_time;
66 	*new_base_time = new_time;
67 }
68 
69 /* Max rates for leak groups */
70 static const u32 spx5_hsch_max_group_rate[SPX5_HSCH_LEAK_GRP_CNT] = {
71 	1048568, /*  1.049 Gbps */
72 	2621420, /*  2.621 Gbps */
73 	10485680, /* 10.486 Gbps */
74 	26214200 /* 26.214 Gbps */
75 };
76 
77 u32 sparx5_get_hsch_max_group_rate(int grp)
78 {
79 	return spx5_hsch_max_group_rate[grp];
80 }
81 
82 static struct sparx5_layer layers[SPX5_HSCH_LAYER_CNT];
83 
84 static u32 sparx5_lg_get_leak_time(struct sparx5 *sparx5, u32 layer, u32 group)
85 {
86 	u32 value;
87 
88 	value = spx5_rd(sparx5, HSCH_HSCH_TIMER_CFG(layer, group));
89 	return HSCH_HSCH_TIMER_CFG_LEAK_TIME_GET(value);
90 }
91 
92 static void sparx5_lg_set_leak_time(struct sparx5 *sparx5, u32 layer, u32 group,
93 				    u32 leak_time)
94 {
95 	spx5_wr(HSCH_HSCH_TIMER_CFG_LEAK_TIME_SET(leak_time), sparx5,
96 		HSCH_HSCH_TIMER_CFG(layer, group));
97 }
98 
99 static u32 sparx5_lg_get_first(struct sparx5 *sparx5, u32 layer, u32 group)
100 {
101 	u32 value;
102 
103 	value = spx5_rd(sparx5, HSCH_HSCH_LEAK_CFG(layer, group));
104 	return HSCH_HSCH_LEAK_CFG_LEAK_FIRST_GET(value);
105 }
106 
107 static u32 sparx5_lg_get_next(struct sparx5 *sparx5, u32 layer, u32 group,
108 			      u32 idx)
109 
110 {
111 	u32 value;
112 
113 	value = spx5_rd(sparx5, HSCH_SE_CONNECT(idx));
114 	return HSCH_SE_CONNECT_SE_LEAK_LINK_GET(value);
115 }
116 
117 static u32 sparx5_lg_get_last(struct sparx5 *sparx5, u32 layer, u32 group)
118 {
119 	u32 itr, next;
120 
121 	itr = sparx5_lg_get_first(sparx5, layer, group);
122 
123 	for (;;) {
124 		next = sparx5_lg_get_next(sparx5, layer, group, itr);
125 		if (itr == next)
126 			return itr;
127 
128 		itr = next;
129 	}
130 }
131 
132 static bool sparx5_lg_is_last(struct sparx5 *sparx5, u32 layer, u32 group,
133 			      u32 idx)
134 {
135 	return idx == sparx5_lg_get_next(sparx5, layer, group, idx);
136 }
137 
138 static bool sparx5_lg_is_first(struct sparx5 *sparx5, u32 layer, u32 group,
139 			       u32 idx)
140 {
141 	return idx == sparx5_lg_get_first(sparx5, layer, group);
142 }
143 
144 static bool sparx5_lg_is_empty(struct sparx5 *sparx5, u32 layer, u32 group)
145 {
146 	return sparx5_lg_get_leak_time(sparx5, layer, group) == 0;
147 }
148 
149 static bool sparx5_lg_is_singular(struct sparx5 *sparx5, u32 layer, u32 group)
150 {
151 	if (sparx5_lg_is_empty(sparx5, layer, group))
152 		return false;
153 
154 	return sparx5_lg_get_first(sparx5, layer, group) ==
155 	       sparx5_lg_get_last(sparx5, layer, group);
156 }
157 
158 static void sparx5_lg_enable(struct sparx5 *sparx5, u32 layer, u32 group,
159 			     u32 leak_time)
160 {
161 	sparx5_lg_set_leak_time(sparx5, layer, group, leak_time);
162 }
163 
164 static void sparx5_lg_disable(struct sparx5 *sparx5, u32 layer, u32 group)
165 {
166 	sparx5_lg_set_leak_time(sparx5, layer, group, 0);
167 }
168 
169 static int sparx5_lg_get_group_by_index(struct sparx5 *sparx5, u32 layer,
170 					u32 idx, u32 *group)
171 {
172 	u32 itr, next;
173 	int i;
174 
175 	for (i = 0; i < SPX5_HSCH_LEAK_GRP_CNT; i++) {
176 		if (sparx5_lg_is_empty(sparx5, layer, i))
177 			continue;
178 
179 		itr = sparx5_lg_get_first(sparx5, layer, i);
180 
181 		for (;;) {
182 			next = sparx5_lg_get_next(sparx5, layer, i, itr);
183 
184 			if (itr == idx) {
185 				*group = i;
186 				return 0; /* Found it */
187 			}
188 			if (itr == next)
189 				break; /* Was not found */
190 
191 			itr = next;
192 		}
193 	}
194 
195 	return -1;
196 }
197 
198 static int sparx5_lg_get_group_by_rate(u32 layer, u32 rate, u32 *group)
199 {
200 	struct sparx5_layer *l = &layers[layer];
201 	struct sparx5_lg *lg;
202 	u32 i;
203 
204 	for (i = 0; i < SPX5_HSCH_LEAK_GRP_CNT; i++) {
205 		lg = &l->leak_groups[i];
206 		if (rate <= lg->max_rate) {
207 			*group = i;
208 			return 0;
209 		}
210 	}
211 
212 	return -1;
213 }
214 
215 static int sparx5_lg_get_adjacent(struct sparx5 *sparx5, u32 layer, u32 group,
216 				  u32 idx, u32 *prev, u32 *next, u32 *first)
217 {
218 	u32 itr;
219 
220 	*first = sparx5_lg_get_first(sparx5, layer, group);
221 	*prev = *first;
222 	*next = *first;
223 	itr = *first;
224 
225 	for (;;) {
226 		*next = sparx5_lg_get_next(sparx5, layer, group, itr);
227 
228 		if (itr == idx)
229 			return 0; /* Found it */
230 
231 		if (itr == *next)
232 			return -1; /* Was not found */
233 
234 		*prev = itr;
235 		itr = *next;
236 	}
237 
238 	return -1;
239 }
240 
241 static int sparx5_lg_conf_set(struct sparx5 *sparx5, u32 layer, u32 group,
242 			      u32 se_first, u32 idx, u32 idx_next, bool empty)
243 {
244 	u32 leak_time = layers[layer].leak_groups[group].leak_time;
245 
246 	/* Stop leaking */
247 	sparx5_lg_disable(sparx5, layer, group);
248 
249 	if (empty)
250 		return 0;
251 
252 	/* Select layer */
253 	spx5_rmw(HSCH_HSCH_CFG_CFG_HSCH_LAYER_SET(layer),
254 		 HSCH_HSCH_CFG_CFG_HSCH_LAYER, sparx5, HSCH_HSCH_CFG_CFG);
255 
256 	/* Link elements */
257 	spx5_wr(HSCH_SE_CONNECT_SE_LEAK_LINK_SET(idx_next), sparx5,
258 		HSCH_SE_CONNECT(idx));
259 
260 	/* Set the first element. */
261 	spx5_rmw(HSCH_HSCH_LEAK_CFG_LEAK_FIRST_SET(se_first),
262 		 HSCH_HSCH_LEAK_CFG_LEAK_FIRST, sparx5,
263 		 HSCH_HSCH_LEAK_CFG(layer, group));
264 
265 	/* Start leaking */
266 	sparx5_lg_enable(sparx5, layer, group, leak_time);
267 
268 	return 0;
269 }
270 
271 static int sparx5_lg_del(struct sparx5 *sparx5, u32 layer, u32 group, u32 idx)
272 {
273 	u32 first, next, prev;
274 	bool empty = false;
275 
276 	/* idx *must* be present in the leak group */
277 	WARN_ON(sparx5_lg_get_adjacent(sparx5, layer, group, idx, &prev, &next,
278 				       &first) < 0);
279 
280 	if (sparx5_lg_is_singular(sparx5, layer, group)) {
281 		empty = true;
282 	} else if (sparx5_lg_is_last(sparx5, layer, group, idx)) {
283 		/* idx is removed, prev is now last */
284 		idx = prev;
285 		next = prev;
286 	} else if (sparx5_lg_is_first(sparx5, layer, group, idx)) {
287 		/* idx is removed and points to itself, first is next */
288 		first = next;
289 		next = idx;
290 	} else {
291 		/* Next is not touched */
292 		idx = prev;
293 	}
294 
295 	return sparx5_lg_conf_set(sparx5, layer, group, first, idx, next,
296 				  empty);
297 }
298 
299 static int sparx5_lg_add(struct sparx5 *sparx5, u32 layer, u32 new_group,
300 			 u32 idx)
301 {
302 	u32 first, next, old_group;
303 
304 	pr_debug("ADD: layer: %d, new_group: %d, idx: %d", layer, new_group,
305 		 idx);
306 
307 	/* Is this SE already shaping ? */
308 	if (sparx5_lg_get_group_by_index(sparx5, layer, idx, &old_group) >= 0) {
309 		if (old_group != new_group) {
310 			/* Delete from old group */
311 			sparx5_lg_del(sparx5, layer, old_group, idx);
312 		} else {
313 			/* Nothing to do here */
314 			return 0;
315 		}
316 	}
317 
318 	/* We always add to head of the list */
319 	first = idx;
320 
321 	if (sparx5_lg_is_empty(sparx5, layer, new_group))
322 		next = idx;
323 	else
324 		next = sparx5_lg_get_first(sparx5, layer, new_group);
325 
326 	return sparx5_lg_conf_set(sparx5, layer, new_group, first, idx, next,
327 				  false);
328 }
329 
330 static int sparx5_shaper_conf_set(struct sparx5_port *port,
331 				  const struct sparx5_shaper *sh, u32 layer,
332 				  u32 idx, u32 group)
333 {
334 	int (*sparx5_lg_action)(struct sparx5 *, u32, u32, u32);
335 	struct sparx5 *sparx5 = port->sparx5;
336 
337 	if (!sh->rate && !sh->burst)
338 		sparx5_lg_action = &sparx5_lg_del;
339 	else
340 		sparx5_lg_action = &sparx5_lg_add;
341 
342 	/* Select layer */
343 	spx5_rmw(HSCH_HSCH_CFG_CFG_HSCH_LAYER_SET(layer),
344 		 HSCH_HSCH_CFG_CFG_HSCH_LAYER, sparx5, HSCH_HSCH_CFG_CFG);
345 
346 	/* Set frame mode */
347 	spx5_rmw(HSCH_SE_CFG_SE_FRM_MODE_SET(sh->mode), HSCH_SE_CFG_SE_FRM_MODE,
348 		 sparx5, HSCH_SE_CFG(idx));
349 
350 	/* Set committed rate and burst */
351 	spx5_wr(HSCH_CIR_CFG_CIR_RATE_SET(sh->rate) |
352 			HSCH_CIR_CFG_CIR_BURST_SET(sh->burst),
353 		sparx5, HSCH_CIR_CFG(idx));
354 
355 	/* This has to be done after the shaper configuration has been set */
356 	sparx5_lg_action(sparx5, layer, group, idx);
357 
358 	return 0;
359 }
360 
361 static u32 sparx5_weight_to_hw_cost(u32 weight_min, u32 weight)
362 {
363 	return ((((SPX5_DWRR_COST_MAX << 4) * weight_min / weight) + 8) >> 4) -
364 	       1;
365 }
366 
367 static int sparx5_dwrr_conf_set(struct sparx5_port *port,
368 				struct sparx5_dwrr *dwrr)
369 {
370 	u32 layer = is_sparx5(port->sparx5) ? 2 : 1;
371 	int i;
372 
373 	spx5_rmw(HSCH_HSCH_CFG_CFG_HSCH_LAYER_SET(layer) |
374 		 HSCH_HSCH_CFG_CFG_CFG_SE_IDX_SET(port->portno),
375 		 HSCH_HSCH_CFG_CFG_HSCH_LAYER | HSCH_HSCH_CFG_CFG_CFG_SE_IDX,
376 		 port->sparx5, HSCH_HSCH_CFG_CFG);
377 
378 	/* Number of *lower* indexes that are arbitrated dwrr */
379 	spx5_rmw(HSCH_SE_CFG_SE_DWRR_CNT_SET(dwrr->count),
380 		 HSCH_SE_CFG_SE_DWRR_CNT, port->sparx5,
381 		 HSCH_SE_CFG(port->portno));
382 
383 	for (i = 0; i < dwrr->count; i++) {
384 		spx5_rmw(HSCH_DWRR_ENTRY_DWRR_COST_SET(dwrr->cost[i]),
385 			 HSCH_DWRR_ENTRY_DWRR_COST, port->sparx5,
386 			 HSCH_DWRR_ENTRY(i));
387 	}
388 
389 	return 0;
390 }
391 
392 static int sparx5_leak_groups_init(struct sparx5 *sparx5)
393 {
394 	const struct sparx5_ops *ops = sparx5->data->ops;
395 	struct sparx5_layer *layer;
396 	u32 sys_clk_per_100ps;
397 	struct sparx5_lg *lg;
398 	u32 leak_time_us;
399 	int i, ii;
400 
401 	sys_clk_per_100ps = spx5_rd(sparx5, HSCH_SYS_CLK_PER);
402 
403 	for (i = 0; i < SPX5_HSCH_LAYER_CNT; i++) {
404 		layer = &layers[i];
405 		for (ii = 0; ii < SPX5_HSCH_LEAK_GRP_CNT; ii++) {
406 			lg = &layer->leak_groups[ii];
407 			lg->max_rate = ops->get_hsch_max_group_rate(i);
408 
409 			/* Calculate the leak time in us, to serve a maximum
410 			 * rate of 'max_rate' for this group
411 			 */
412 			leak_time_us = (SPX5_SE_RATE_MAX * 1000) / lg->max_rate;
413 
414 			/* Hardware wants leak time in ns */
415 			lg->leak_time = 1000 * leak_time_us;
416 
417 			/* Calculate resolution */
418 			lg->resolution = 1000 / leak_time_us;
419 
420 			/* Maximum number of shapers that can be served by
421 			 * this leak group
422 			 */
423 			lg->max_ses = (1000 * leak_time_us) / sys_clk_per_100ps;
424 
425 			/* Example:
426 			 * Wanted bandwidth is 100Mbit:
427 			 *
428 			 * 100 mbps can be served by leak group zero.
429 			 *
430 			 * leak_time is 125000 ns.
431 			 * resolution is: 8
432 			 *
433 			 * cir          = 100000 / 8 = 12500
434 			 * leaks_pr_sec = 125000 / 10^9 = 8000
435 			 * bw           = 12500 * 8000 = 10^8 (100 Mbit)
436 			 */
437 
438 			/* Disable by default - this also indicates an empty
439 			 * leak group
440 			 */
441 			sparx5_lg_disable(sparx5, i, ii);
442 		}
443 	}
444 
445 	return 0;
446 }
447 
448 int sparx5_qos_init(struct sparx5 *sparx5)
449 {
450 	int ret;
451 
452 	ret = sparx5_leak_groups_init(sparx5);
453 	if (ret < 0)
454 		return ret;
455 
456 	ret = sparx5_dcb_init(sparx5);
457 	if (ret < 0)
458 		return ret;
459 
460 	sparx5_psfp_init(sparx5);
461 
462 	return 0;
463 }
464 
465 int sparx5_tc_mqprio_add(struct net_device *ndev, u8 num_tc)
466 {
467 	int i;
468 
469 	if (num_tc != SPX5_PRIOS) {
470 		netdev_err(ndev, "Only %d traffic classes supported\n",
471 			   SPX5_PRIOS);
472 		return -EINVAL;
473 	}
474 
475 	netdev_set_num_tc(ndev, num_tc);
476 
477 	for (i = 0; i < num_tc; i++)
478 		netdev_set_tc_queue(ndev, i, 1, i);
479 
480 	netdev_dbg(ndev, "dev->num_tc %u dev->real_num_tx_queues %u\n",
481 		   ndev->num_tc, ndev->real_num_tx_queues);
482 
483 	return 0;
484 }
485 
486 int sparx5_tc_mqprio_del(struct net_device *ndev)
487 {
488 	netdev_reset_tc(ndev);
489 
490 	netdev_dbg(ndev, "dev->num_tc %u dev->real_num_tx_queues %u\n",
491 		   ndev->num_tc, ndev->real_num_tx_queues);
492 
493 	return 0;
494 }
495 
496 int sparx5_tc_tbf_add(struct sparx5_port *port,
497 		      struct tc_tbf_qopt_offload_replace_params *params,
498 		      u32 layer, u32 idx)
499 {
500 	struct sparx5_shaper sh = {
501 		.mode = SPX5_SE_MODE_DATARATE,
502 		.rate = div_u64(params->rate.rate_bytes_ps, 1000) * 8,
503 		.burst = params->max_size,
504 	};
505 	struct sparx5_lg *lg;
506 	u32 group;
507 
508 	/* Find suitable group for this se */
509 	if (sparx5_lg_get_group_by_rate(layer, sh.rate, &group) < 0) {
510 		pr_debug("Could not find leak group for se with rate: %d",
511 			 sh.rate);
512 		return -EINVAL;
513 	}
514 
515 	lg = &layers[layer].leak_groups[group];
516 
517 	pr_debug("Found matching group (speed: %d)\n", lg->max_rate);
518 
519 	if (sh.rate < SPX5_SE_RATE_MIN || sh.burst < SPX5_SE_BURST_MIN)
520 		return -EINVAL;
521 
522 	/* Calculate committed rate and burst */
523 	sh.rate = DIV_ROUND_UP(sh.rate, lg->resolution);
524 	sh.burst = DIV_ROUND_UP(sh.burst, SPX5_SE_BURST_UNIT);
525 
526 	if (sh.rate > SPX5_SE_RATE_MAX || sh.burst > SPX5_SE_BURST_MAX)
527 		return -EINVAL;
528 
529 	return sparx5_shaper_conf_set(port, &sh, layer, idx, group);
530 }
531 
532 int sparx5_tc_tbf_del(struct sparx5_port *port, u32 layer, u32 idx)
533 {
534 	struct sparx5_shaper sh = {0};
535 	u32 group;
536 
537 	sparx5_lg_get_group_by_index(port->sparx5, layer, idx, &group);
538 
539 	return sparx5_shaper_conf_set(port, &sh, layer, idx, group);
540 }
541 
542 int sparx5_tc_ets_add(struct sparx5_port *port,
543 		      struct tc_ets_qopt_offload_replace_params *params)
544 {
545 	struct sparx5_dwrr dwrr = {0};
546 	/* Minimum weight for each iteration */
547 	unsigned int w_min = 100;
548 	int i;
549 
550 	/* Find minimum weight for all dwrr bands */
551 	for (i = 0; i < SPX5_PRIOS; i++) {
552 		if (params->quanta[i] == 0)
553 			continue;
554 		w_min = min(w_min, params->weights[i]);
555 	}
556 
557 	for (i = 0; i < SPX5_PRIOS; i++) {
558 		/* Strict band; skip */
559 		if (params->quanta[i] == 0)
560 			continue;
561 
562 		dwrr.count++;
563 
564 		/* On the sparx5, bands with higher indexes are preferred and
565 		 * arbitrated strict. Strict bands are put in the lower indexes,
566 		 * by tc, so we reverse the bands here.
567 		 *
568 		 * Also convert the weight to something the hardware
569 		 * understands.
570 		 */
571 		dwrr.cost[SPX5_PRIOS - i - 1] =
572 			sparx5_weight_to_hw_cost(w_min, params->weights[i]);
573 	}
574 
575 	return sparx5_dwrr_conf_set(port, &dwrr);
576 }
577 
578 int sparx5_tc_ets_del(struct sparx5_port *port)
579 {
580 	struct sparx5_dwrr dwrr = {0};
581 
582 	return sparx5_dwrr_conf_set(port, &dwrr);
583 }
584