xref: /openbmc/linux/drivers/usb/host/xhci-mtk-sch.c (revision 3c8c1539)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2015 MediaTek Inc.
4  * Author:
5  *  Zhigang.Wei <zhigang.wei@mediatek.com>
6  *  Chunfeng.Yun <chunfeng.yun@mediatek.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 
13 #include "xhci.h"
14 #include "xhci-mtk.h"
15 
16 #define SSP_BW_BOUNDARY	130000
17 #define SS_BW_BOUNDARY	51000
18 /* table 5-5. High-speed Isoc Transaction Limits in usb_20 spec */
19 #define HS_BW_BOUNDARY	6144
20 /* usb2 spec section11.18.1: at most 188 FS bytes per microframe */
21 #define FS_PAYLOAD_MAX 188
22 /*
23  * max number of microframes for split transfer,
24  * for fs isoc in : 1 ss + 1 idle + 7 cs
25  */
26 #define TT_MICROFRAMES_MAX 9
27 
28 #define DBG_BUF_EN	64
29 
30 /* schedule error type */
31 #define ESCH_SS_Y6		1001
32 #define ESCH_SS_OVERLAP		1002
33 #define ESCH_CS_OVERFLOW	1003
34 #define ESCH_BW_OVERFLOW	1004
35 #define ESCH_FIXME		1005
36 
37 /* mtk scheduler bitmasks */
38 #define EP_BPKTS(p)	((p) & 0x7f)
39 #define EP_BCSCOUNT(p)	(((p) & 0x7) << 8)
40 #define EP_BBM(p)	((p) << 11)
41 #define EP_BOFFSET(p)	((p) & 0x3fff)
42 #define EP_BREPEAT(p)	(((p) & 0x7fff) << 16)
43 
44 static char *sch_error_string(int err_num)
45 {
46 	switch (err_num) {
47 	case ESCH_SS_Y6:
48 		return "Can't schedule Start-Split in Y6";
49 	case ESCH_SS_OVERLAP:
50 		return "Can't find a suitable Start-Split location";
51 	case ESCH_CS_OVERFLOW:
52 		return "The last Complete-Split is greater than 7";
53 	case ESCH_BW_OVERFLOW:
54 		return "Bandwidth exceeds the maximum limit";
55 	case ESCH_FIXME:
56 		return "FIXME, to be resolved";
57 	default:
58 		return "Unknown";
59 	}
60 }
61 
62 static int is_fs_or_ls(enum usb_device_speed speed)
63 {
64 	return speed == USB_SPEED_FULL || speed == USB_SPEED_LOW;
65 }
66 
67 static const char *
68 decode_ep(struct usb_host_endpoint *ep, enum usb_device_speed speed)
69 {
70 	static char buf[DBG_BUF_EN];
71 	struct usb_endpoint_descriptor *epd = &ep->desc;
72 	unsigned int interval;
73 	const char *unit;
74 
75 	interval = usb_decode_interval(epd, speed);
76 	if (interval % 1000) {
77 		unit = "us";
78 	} else {
79 		unit = "ms";
80 		interval /= 1000;
81 	}
82 
83 	snprintf(buf, DBG_BUF_EN, "%s ep%d%s %s, mpkt:%d, interval:%d/%d%s",
84 		 usb_speed_string(speed), usb_endpoint_num(epd),
85 		 usb_endpoint_dir_in(epd) ? "in" : "out",
86 		 usb_ep_type_string(usb_endpoint_type(epd)),
87 		 usb_endpoint_maxp(epd), epd->bInterval, interval, unit);
88 
89 	return buf;
90 }
91 
92 static u32 get_bw_boundary(enum usb_device_speed speed)
93 {
94 	u32 boundary;
95 
96 	switch (speed) {
97 	case USB_SPEED_SUPER_PLUS:
98 		boundary = SSP_BW_BOUNDARY;
99 		break;
100 	case USB_SPEED_SUPER:
101 		boundary = SS_BW_BOUNDARY;
102 		break;
103 	default:
104 		boundary = HS_BW_BOUNDARY;
105 		break;
106 	}
107 
108 	return boundary;
109 }
110 
111 /*
112 * get the bandwidth domain which @ep belongs to.
113 *
114 * the bandwidth domain array is saved to @sch_array of struct xhci_hcd_mtk,
115 * each HS root port is treated as a single bandwidth domain,
116 * but each SS root port is treated as two bandwidth domains, one for IN eps,
117 * one for OUT eps.
118 * @real_port value is defined as follow according to xHCI spec:
119 * 1 for SSport0, ..., N+1 for SSportN, N+2 for HSport0, N+3 for HSport1, etc
120 * so the bandwidth domain array is organized as follow for simplification:
121 * SSport0-OUT, SSport0-IN, ..., SSportX-OUT, SSportX-IN, HSport0, ..., HSportY
122 */
123 static struct mu3h_sch_bw_info *
124 get_bw_info(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
125 	    struct usb_host_endpoint *ep)
126 {
127 	struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
128 	struct xhci_virt_device *virt_dev;
129 	int bw_index;
130 
131 	virt_dev = xhci->devs[udev->slot_id];
132 	if (!virt_dev->real_port) {
133 		WARN_ONCE(1, "%s invalid real_port\n", dev_name(&udev->dev));
134 		return NULL;
135 	}
136 
137 	if (udev->speed >= USB_SPEED_SUPER) {
138 		if (usb_endpoint_dir_out(&ep->desc))
139 			bw_index = (virt_dev->real_port - 1) * 2;
140 		else
141 			bw_index = (virt_dev->real_port - 1) * 2 + 1;
142 	} else {
143 		/* add one more for each SS port */
144 		bw_index = virt_dev->real_port + xhci->usb3_rhub.num_ports - 1;
145 	}
146 
147 	return &mtk->sch_array[bw_index];
148 }
149 
150 static u32 get_esit(struct xhci_ep_ctx *ep_ctx)
151 {
152 	u32 esit;
153 
154 	esit = 1 << CTX_TO_EP_INTERVAL(le32_to_cpu(ep_ctx->ep_info));
155 	if (esit > XHCI_MTK_MAX_ESIT)
156 		esit = XHCI_MTK_MAX_ESIT;
157 
158 	return esit;
159 }
160 
161 static struct mu3h_sch_tt *find_tt(struct usb_device *udev)
162 {
163 	struct usb_tt *utt = udev->tt;
164 	struct mu3h_sch_tt *tt, **tt_index, **ptt;
165 	bool allocated_index = false;
166 
167 	if (!utt)
168 		return NULL;	/* Not below a TT */
169 
170 	/*
171 	 * Find/create our data structure.
172 	 * For hubs with a single TT, we get it directly.
173 	 * For hubs with multiple TTs, there's an extra level of pointers.
174 	 */
175 	tt_index = NULL;
176 	if (utt->multi) {
177 		tt_index = utt->hcpriv;
178 		if (!tt_index) {	/* Create the index array */
179 			tt_index = kcalloc(utt->hub->maxchild,
180 					sizeof(*tt_index), GFP_KERNEL);
181 			if (!tt_index)
182 				return ERR_PTR(-ENOMEM);
183 			utt->hcpriv = tt_index;
184 			allocated_index = true;
185 		}
186 		ptt = &tt_index[udev->ttport - 1];
187 	} else {
188 		ptt = (struct mu3h_sch_tt **) &utt->hcpriv;
189 	}
190 
191 	tt = *ptt;
192 	if (!tt) {	/* Create the mu3h_sch_tt */
193 		tt = kzalloc(sizeof(*tt), GFP_KERNEL);
194 		if (!tt) {
195 			if (allocated_index) {
196 				utt->hcpriv = NULL;
197 				kfree(tt_index);
198 			}
199 			return ERR_PTR(-ENOMEM);
200 		}
201 		INIT_LIST_HEAD(&tt->ep_list);
202 		*ptt = tt;
203 	}
204 
205 	return tt;
206 }
207 
208 /* Release the TT above udev, if it's not in use */
209 static void drop_tt(struct usb_device *udev)
210 {
211 	struct usb_tt *utt = udev->tt;
212 	struct mu3h_sch_tt *tt, **tt_index, **ptt;
213 	int i, cnt;
214 
215 	if (!utt || !utt->hcpriv)
216 		return;		/* Not below a TT, or never allocated */
217 
218 	cnt = 0;
219 	if (utt->multi) {
220 		tt_index = utt->hcpriv;
221 		ptt = &tt_index[udev->ttport - 1];
222 		/*  How many entries are left in tt_index? */
223 		for (i = 0; i < utt->hub->maxchild; ++i)
224 			cnt += !!tt_index[i];
225 	} else {
226 		tt_index = NULL;
227 		ptt = (struct mu3h_sch_tt **)&utt->hcpriv;
228 	}
229 
230 	tt = *ptt;
231 	if (!tt || !list_empty(&tt->ep_list))
232 		return;		/* never allocated , or still in use*/
233 
234 	*ptt = NULL;
235 	kfree(tt);
236 
237 	if (cnt == 1) {
238 		utt->hcpriv = NULL;
239 		kfree(tt_index);
240 	}
241 }
242 
243 static struct mu3h_sch_ep_info *
244 create_sch_ep(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
245 	      struct usb_host_endpoint *ep, struct xhci_ep_ctx *ep_ctx)
246 {
247 	struct mu3h_sch_ep_info *sch_ep;
248 	struct mu3h_sch_bw_info *bw_info;
249 	struct mu3h_sch_tt *tt = NULL;
250 	u32 len_bw_budget_table;
251 	size_t mem_size;
252 
253 	bw_info = get_bw_info(mtk, udev, ep);
254 	if (!bw_info)
255 		return ERR_PTR(-ENODEV);
256 
257 	if (is_fs_or_ls(udev->speed))
258 		len_bw_budget_table = TT_MICROFRAMES_MAX;
259 	else if ((udev->speed >= USB_SPEED_SUPER)
260 			&& usb_endpoint_xfer_isoc(&ep->desc))
261 		len_bw_budget_table = get_esit(ep_ctx);
262 	else
263 		len_bw_budget_table = 1;
264 
265 	mem_size = sizeof(struct mu3h_sch_ep_info) +
266 			len_bw_budget_table * sizeof(u32);
267 	sch_ep = kzalloc(mem_size, GFP_KERNEL);
268 	if (!sch_ep)
269 		return ERR_PTR(-ENOMEM);
270 
271 	if (is_fs_or_ls(udev->speed)) {
272 		tt = find_tt(udev);
273 		if (IS_ERR(tt)) {
274 			kfree(sch_ep);
275 			return ERR_PTR(-ENOMEM);
276 		}
277 	}
278 
279 	sch_ep->bw_info = bw_info;
280 	sch_ep->sch_tt = tt;
281 	sch_ep->ep = ep;
282 	sch_ep->speed = udev->speed;
283 	INIT_LIST_HEAD(&sch_ep->endpoint);
284 	INIT_LIST_HEAD(&sch_ep->tt_endpoint);
285 	INIT_HLIST_NODE(&sch_ep->hentry);
286 
287 	return sch_ep;
288 }
289 
290 static void setup_sch_info(struct xhci_ep_ctx *ep_ctx,
291 			   struct mu3h_sch_ep_info *sch_ep)
292 {
293 	u32 ep_type;
294 	u32 maxpkt;
295 	u32 max_burst;
296 	u32 mult;
297 	u32 esit_pkts;
298 	u32 max_esit_payload;
299 	u32 *bwb_table = sch_ep->bw_budget_table;
300 	int i;
301 
302 	ep_type = CTX_TO_EP_TYPE(le32_to_cpu(ep_ctx->ep_info2));
303 	maxpkt = MAX_PACKET_DECODED(le32_to_cpu(ep_ctx->ep_info2));
304 	max_burst = CTX_TO_MAX_BURST(le32_to_cpu(ep_ctx->ep_info2));
305 	mult = CTX_TO_EP_MULT(le32_to_cpu(ep_ctx->ep_info));
306 	max_esit_payload =
307 		(CTX_TO_MAX_ESIT_PAYLOAD_HI(
308 			le32_to_cpu(ep_ctx->ep_info)) << 16) |
309 		 CTX_TO_MAX_ESIT_PAYLOAD(le32_to_cpu(ep_ctx->tx_info));
310 
311 	sch_ep->esit = get_esit(ep_ctx);
312 	sch_ep->num_esit = XHCI_MTK_MAX_ESIT / sch_ep->esit;
313 	sch_ep->ep_type = ep_type;
314 	sch_ep->maxpkt = maxpkt;
315 	sch_ep->offset = 0;
316 	sch_ep->burst_mode = 0;
317 	sch_ep->repeat = 0;
318 
319 	if (sch_ep->speed == USB_SPEED_HIGH) {
320 		sch_ep->cs_count = 0;
321 
322 		/*
323 		 * usb_20 spec section5.9
324 		 * a single microframe is enough for HS synchromous endpoints
325 		 * in a interval
326 		 */
327 		sch_ep->num_budget_microframes = 1;
328 
329 		/*
330 		 * xHCI spec section6.2.3.4
331 		 * @max_burst is the number of additional transactions
332 		 * opportunities per microframe
333 		 */
334 		sch_ep->pkts = max_burst + 1;
335 		sch_ep->bw_cost_per_microframe = maxpkt * sch_ep->pkts;
336 		bwb_table[0] = sch_ep->bw_cost_per_microframe;
337 	} else if (sch_ep->speed >= USB_SPEED_SUPER) {
338 		/* usb3_r1 spec section4.4.7 & 4.4.8 */
339 		sch_ep->cs_count = 0;
340 		sch_ep->burst_mode = 1;
341 		/*
342 		 * some device's (d)wBytesPerInterval is set as 0,
343 		 * then max_esit_payload is 0, so evaluate esit_pkts from
344 		 * mult and burst
345 		 */
346 		esit_pkts = DIV_ROUND_UP(max_esit_payload, maxpkt);
347 		if (esit_pkts == 0)
348 			esit_pkts = (mult + 1) * (max_burst + 1);
349 
350 		if (ep_type == INT_IN_EP || ep_type == INT_OUT_EP) {
351 			sch_ep->pkts = esit_pkts;
352 			sch_ep->num_budget_microframes = 1;
353 			bwb_table[0] = maxpkt * sch_ep->pkts;
354 		}
355 
356 		if (ep_type == ISOC_IN_EP || ep_type == ISOC_OUT_EP) {
357 
358 			if (sch_ep->esit == 1)
359 				sch_ep->pkts = esit_pkts;
360 			else if (esit_pkts <= sch_ep->esit)
361 				sch_ep->pkts = 1;
362 			else
363 				sch_ep->pkts = roundup_pow_of_two(esit_pkts)
364 					/ sch_ep->esit;
365 
366 			sch_ep->num_budget_microframes =
367 				DIV_ROUND_UP(esit_pkts, sch_ep->pkts);
368 
369 			sch_ep->repeat = !!(sch_ep->num_budget_microframes > 1);
370 			sch_ep->bw_cost_per_microframe = maxpkt * sch_ep->pkts;
371 
372 			for (i = 0; i < sch_ep->num_budget_microframes - 1; i++)
373 				bwb_table[i] = sch_ep->bw_cost_per_microframe;
374 
375 			/* last one <= bw_cost_per_microframe */
376 			bwb_table[i] = maxpkt * esit_pkts
377 				       - i * sch_ep->bw_cost_per_microframe;
378 		}
379 	} else if (is_fs_or_ls(sch_ep->speed)) {
380 		sch_ep->pkts = 1; /* at most one packet for each microframe */
381 
382 		/*
383 		 * num_budget_microframes and cs_count will be updated when
384 		 * check TT for INT_OUT_EP, ISOC/INT_IN_EP type
385 		 */
386 		sch_ep->cs_count = DIV_ROUND_UP(maxpkt, FS_PAYLOAD_MAX);
387 		sch_ep->num_budget_microframes = sch_ep->cs_count;
388 		sch_ep->bw_cost_per_microframe =
389 			(maxpkt < FS_PAYLOAD_MAX) ? maxpkt : FS_PAYLOAD_MAX;
390 
391 		/* init budget table */
392 		if (ep_type == ISOC_OUT_EP) {
393 			for (i = 0; i < sch_ep->num_budget_microframes; i++)
394 				bwb_table[i] =	sch_ep->bw_cost_per_microframe;
395 		} else if (ep_type == INT_OUT_EP) {
396 			/* only first one consumes bandwidth, others as zero */
397 			bwb_table[0] = sch_ep->bw_cost_per_microframe;
398 		} else { /* INT_IN_EP or ISOC_IN_EP */
399 			bwb_table[0] = 0; /* start split */
400 			bwb_table[1] = 0; /* idle */
401 			/*
402 			 * due to cs_count will be updated according to cs
403 			 * position, assign all remainder budget array
404 			 * elements as @bw_cost_per_microframe, but only first
405 			 * @num_budget_microframes elements will be used later
406 			 */
407 			for (i = 2; i < TT_MICROFRAMES_MAX; i++)
408 				bwb_table[i] =	sch_ep->bw_cost_per_microframe;
409 		}
410 	}
411 }
412 
413 /* Get maximum bandwidth when we schedule at offset slot. */
414 static u32 get_max_bw(struct mu3h_sch_bw_info *sch_bw,
415 	struct mu3h_sch_ep_info *sch_ep, u32 offset)
416 {
417 	u32 max_bw = 0;
418 	u32 bw;
419 	int i, j, k;
420 
421 	for (i = 0; i < sch_ep->num_esit; i++) {
422 		u32 base = offset + i * sch_ep->esit;
423 
424 		for (j = 0; j < sch_ep->num_budget_microframes; j++) {
425 			k = XHCI_MTK_BW_INDEX(base + j);
426 			bw = sch_bw->bus_bw[k] + sch_ep->bw_budget_table[j];
427 			if (bw > max_bw)
428 				max_bw = bw;
429 		}
430 	}
431 	return max_bw;
432 }
433 
434 static void update_bus_bw(struct mu3h_sch_bw_info *sch_bw,
435 	struct mu3h_sch_ep_info *sch_ep, bool used)
436 {
437 	u32 base;
438 	int i, j, k;
439 
440 	for (i = 0; i < sch_ep->num_esit; i++) {
441 		base = sch_ep->offset + i * sch_ep->esit;
442 		for (j = 0; j < sch_ep->num_budget_microframes; j++) {
443 			k = XHCI_MTK_BW_INDEX(base + j);
444 			if (used)
445 				sch_bw->bus_bw[k] += sch_ep->bw_budget_table[j];
446 			else
447 				sch_bw->bus_bw[k] -= sch_ep->bw_budget_table[j];
448 		}
449 	}
450 }
451 
452 static int check_fs_bus_bw(struct mu3h_sch_ep_info *sch_ep, int offset)
453 {
454 	struct mu3h_sch_tt *tt = sch_ep->sch_tt;
455 	u32 tmp;
456 	int base;
457 	int i, j, k;
458 
459 	for (i = 0; i < sch_ep->num_esit; i++) {
460 		base = offset + i * sch_ep->esit;
461 
462 		/*
463 		 * Compared with hs bus, no matter what ep type,
464 		 * the hub will always delay one uframe to send data
465 		 */
466 		for (j = 0; j < sch_ep->num_budget_microframes; j++) {
467 			k = XHCI_MTK_BW_INDEX(base + j);
468 			tmp = tt->fs_bus_bw[k] + sch_ep->bw_budget_table[j];
469 			if (tmp > FS_PAYLOAD_MAX)
470 				return -ESCH_BW_OVERFLOW;
471 		}
472 	}
473 
474 	return 0;
475 }
476 
477 static int check_sch_tt(struct mu3h_sch_ep_info *sch_ep, u32 offset)
478 {
479 	u32 extra_cs_count;
480 	u32 start_ss, last_ss;
481 	u32 start_cs, last_cs;
482 
483 	if (!sch_ep->sch_tt)
484 		return 0;
485 
486 	start_ss = offset % 8;
487 
488 	if (sch_ep->ep_type == ISOC_OUT_EP) {
489 		last_ss = start_ss + sch_ep->cs_count - 1;
490 
491 		/*
492 		 * usb_20 spec section11.18:
493 		 * must never schedule Start-Split in Y6
494 		 */
495 		if (!(start_ss == 7 || last_ss < 6))
496 			return -ESCH_SS_Y6;
497 
498 	} else {
499 		u32 cs_count = DIV_ROUND_UP(sch_ep->maxpkt, FS_PAYLOAD_MAX);
500 
501 		/*
502 		 * usb_20 spec section11.18:
503 		 * must never schedule Start-Split in Y6
504 		 */
505 		if (start_ss == 6)
506 			return -ESCH_SS_Y6;
507 
508 		/* one uframe for ss + one uframe for idle */
509 		start_cs = (start_ss + 2) % 8;
510 		last_cs = start_cs + cs_count - 1;
511 
512 		if (last_cs > 7)
513 			return -ESCH_CS_OVERFLOW;
514 
515 		if (sch_ep->ep_type == ISOC_IN_EP)
516 			extra_cs_count = (last_cs == 7) ? 1 : 2;
517 		else /*  ep_type : INTR IN / INTR OUT */
518 			extra_cs_count = 1;
519 
520 		cs_count += extra_cs_count;
521 		if (cs_count > 7)
522 			cs_count = 7; /* HW limit */
523 
524 		sch_ep->cs_count = cs_count;
525 		/* one for ss, the other for idle */
526 		sch_ep->num_budget_microframes = cs_count + 2;
527 
528 		/*
529 		 * if interval=1, maxp >752, num_budge_micoframe is larger
530 		 * than sch_ep->esit, will overstep boundary
531 		 */
532 		if (sch_ep->num_budget_microframes > sch_ep->esit)
533 			sch_ep->num_budget_microframes = sch_ep->esit;
534 	}
535 
536 	return check_fs_bus_bw(sch_ep, offset);
537 }
538 
539 static void update_sch_tt(struct mu3h_sch_ep_info *sch_ep, bool used)
540 {
541 	struct mu3h_sch_tt *tt = sch_ep->sch_tt;
542 	u32 base;
543 	int i, j, k;
544 
545 	for (i = 0; i < sch_ep->num_esit; i++) {
546 		base = sch_ep->offset + i * sch_ep->esit;
547 
548 		for (j = 0; j < sch_ep->num_budget_microframes; j++) {
549 			k = XHCI_MTK_BW_INDEX(base + j);
550 			if (used)
551 				tt->fs_bus_bw[k] += sch_ep->bw_budget_table[j];
552 			else
553 				tt->fs_bus_bw[k] -= sch_ep->bw_budget_table[j];
554 		}
555 	}
556 
557 	if (used)
558 		list_add_tail(&sch_ep->tt_endpoint, &tt->ep_list);
559 	else
560 		list_del(&sch_ep->tt_endpoint);
561 }
562 
563 static int load_ep_bw(struct mu3h_sch_bw_info *sch_bw,
564 		      struct mu3h_sch_ep_info *sch_ep, bool loaded)
565 {
566 	if (sch_ep->sch_tt)
567 		update_sch_tt(sch_ep, loaded);
568 
569 	/* update bus bandwidth info */
570 	update_bus_bw(sch_bw, sch_ep, loaded);
571 	sch_ep->allocated = loaded;
572 
573 	return 0;
574 }
575 
576 static int check_sch_bw(struct mu3h_sch_ep_info *sch_ep)
577 {
578 	struct mu3h_sch_bw_info *sch_bw = sch_ep->bw_info;
579 	const u32 bw_boundary = get_bw_boundary(sch_ep->speed);
580 	u32 offset;
581 	u32 worst_bw;
582 	u32 min_bw = ~0;
583 	int min_index = -1;
584 	int ret = 0;
585 
586 	/*
587 	 * Search through all possible schedule microframes.
588 	 * and find a microframe where its worst bandwidth is minimum.
589 	 */
590 	for (offset = 0; offset < sch_ep->esit; offset++) {
591 		ret = check_sch_tt(sch_ep, offset);
592 		if (ret)
593 			continue;
594 
595 		worst_bw = get_max_bw(sch_bw, sch_ep, offset);
596 		if (worst_bw > bw_boundary)
597 			continue;
598 
599 		if (min_bw > worst_bw) {
600 			min_bw = worst_bw;
601 			min_index = offset;
602 		}
603 
604 		/* use first-fit for LS/FS */
605 		if (sch_ep->sch_tt && min_index >= 0)
606 			break;
607 
608 		if (min_bw == 0)
609 			break;
610 	}
611 
612 	if (min_index < 0)
613 		return ret ? ret : -ESCH_BW_OVERFLOW;
614 
615 	sch_ep->offset = min_index;
616 
617 	return load_ep_bw(sch_bw, sch_ep, true);
618 }
619 
620 static void destroy_sch_ep(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
621 			   struct mu3h_sch_ep_info *sch_ep)
622 {
623 	/* only release ep bw check passed by check_sch_bw() */
624 	if (sch_ep->allocated)
625 		load_ep_bw(sch_ep->bw_info, sch_ep, false);
626 
627 	if (sch_ep->sch_tt)
628 		drop_tt(udev);
629 
630 	list_del(&sch_ep->endpoint);
631 	hlist_del(&sch_ep->hentry);
632 	kfree(sch_ep);
633 }
634 
635 static bool need_bw_sch(struct usb_device *udev,
636 			struct usb_host_endpoint *ep)
637 {
638 	bool has_tt = udev->tt && udev->tt->hub->parent;
639 
640 	/* only for periodic endpoints */
641 	if (usb_endpoint_xfer_control(&ep->desc)
642 		|| usb_endpoint_xfer_bulk(&ep->desc))
643 		return false;
644 
645 	/*
646 	 * for LS & FS periodic endpoints which its device is not behind
647 	 * a TT are also ignored, root-hub will schedule them directly,
648 	 * but need set @bpkts field of endpoint context to 1.
649 	 */
650 	if (is_fs_or_ls(udev->speed) && !has_tt)
651 		return false;
652 
653 	/* skip endpoint with zero maxpkt */
654 	if (usb_endpoint_maxp(&ep->desc) == 0)
655 		return false;
656 
657 	return true;
658 }
659 
660 int xhci_mtk_sch_init(struct xhci_hcd_mtk *mtk)
661 {
662 	struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
663 	struct mu3h_sch_bw_info *sch_array;
664 	int num_usb_bus;
665 
666 	/* ss IN and OUT are separated */
667 	num_usb_bus = xhci->usb3_rhub.num_ports * 2 + xhci->usb2_rhub.num_ports;
668 
669 	sch_array = kcalloc(num_usb_bus, sizeof(*sch_array), GFP_KERNEL);
670 	if (sch_array == NULL)
671 		return -ENOMEM;
672 
673 	mtk->sch_array = sch_array;
674 
675 	INIT_LIST_HEAD(&mtk->bw_ep_chk_list);
676 	hash_init(mtk->sch_ep_hash);
677 
678 	return 0;
679 }
680 
681 void xhci_mtk_sch_exit(struct xhci_hcd_mtk *mtk)
682 {
683 	kfree(mtk->sch_array);
684 }
685 
686 static int add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
687 			struct usb_host_endpoint *ep)
688 {
689 	struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
690 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
691 	struct xhci_ep_ctx *ep_ctx;
692 	struct xhci_virt_device *virt_dev;
693 	struct mu3h_sch_ep_info *sch_ep;
694 	unsigned int ep_index;
695 
696 	virt_dev = xhci->devs[udev->slot_id];
697 	ep_index = xhci_get_endpoint_index(&ep->desc);
698 	ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
699 
700 	if (!need_bw_sch(udev, ep)) {
701 		/*
702 		 * set @bpkts to 1 if it is LS or FS periodic endpoint, and its
703 		 * device does not connected through an external HS hub
704 		 */
705 		if (usb_endpoint_xfer_int(&ep->desc)
706 			|| usb_endpoint_xfer_isoc(&ep->desc))
707 			ep_ctx->reserved[0] = cpu_to_le32(EP_BPKTS(1));
708 
709 		return 0;
710 	}
711 
712 	xhci_dbg(xhci, "%s %s\n", __func__, decode_ep(ep, udev->speed));
713 
714 	sch_ep = create_sch_ep(mtk, udev, ep, ep_ctx);
715 	if (IS_ERR_OR_NULL(sch_ep))
716 		return -ENOMEM;
717 
718 	setup_sch_info(ep_ctx, sch_ep);
719 
720 	list_add_tail(&sch_ep->endpoint, &mtk->bw_ep_chk_list);
721 	hash_add(mtk->sch_ep_hash, &sch_ep->hentry, (unsigned long)ep);
722 
723 	return 0;
724 }
725 
726 static void drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
727 			  struct usb_host_endpoint *ep)
728 {
729 	struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
730 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
731 	struct mu3h_sch_ep_info *sch_ep;
732 	struct hlist_node *hn;
733 
734 	if (!need_bw_sch(udev, ep))
735 		return;
736 
737 	xhci_err(xhci, "%s %s\n", __func__, decode_ep(ep, udev->speed));
738 
739 	hash_for_each_possible_safe(mtk->sch_ep_hash, sch_ep,
740 				    hn, hentry, (unsigned long)ep) {
741 		if (sch_ep->ep == ep) {
742 			destroy_sch_ep(mtk, udev, sch_ep);
743 			break;
744 		}
745 	}
746 }
747 
748 int xhci_mtk_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
749 {
750 	struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
751 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
752 	struct xhci_virt_device *virt_dev = xhci->devs[udev->slot_id];
753 	struct mu3h_sch_ep_info *sch_ep;
754 	int ret;
755 
756 	xhci_dbg(xhci, "%s() udev %s\n", __func__, dev_name(&udev->dev));
757 
758 	list_for_each_entry(sch_ep, &mtk->bw_ep_chk_list, endpoint) {
759 		struct xhci_ep_ctx *ep_ctx;
760 		struct usb_host_endpoint *ep = sch_ep->ep;
761 		unsigned int ep_index = xhci_get_endpoint_index(&ep->desc);
762 
763 		ret = check_sch_bw(sch_ep);
764 		if (ret) {
765 			xhci_err(xhci, "Not enough bandwidth! (%s)\n",
766 				 sch_error_string(-ret));
767 			return -ENOSPC;
768 		}
769 
770 		ep_ctx = xhci_get_ep_ctx(xhci, virt_dev->in_ctx, ep_index);
771 		ep_ctx->reserved[0] = cpu_to_le32(EP_BPKTS(sch_ep->pkts)
772 			| EP_BCSCOUNT(sch_ep->cs_count)
773 			| EP_BBM(sch_ep->burst_mode));
774 		ep_ctx->reserved[1] = cpu_to_le32(EP_BOFFSET(sch_ep->offset)
775 			| EP_BREPEAT(sch_ep->repeat));
776 
777 		xhci_dbg(xhci, " PKTS:%x, CSCOUNT:%x, BM:%x, OFFSET:%x, REPEAT:%x\n",
778 			sch_ep->pkts, sch_ep->cs_count, sch_ep->burst_mode,
779 			sch_ep->offset, sch_ep->repeat);
780 	}
781 
782 	ret = xhci_check_bandwidth(hcd, udev);
783 	if (!ret)
784 		INIT_LIST_HEAD(&mtk->bw_ep_chk_list);
785 
786 	return ret;
787 }
788 
789 void xhci_mtk_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
790 {
791 	struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
792 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
793 	struct mu3h_sch_ep_info *sch_ep, *tmp;
794 
795 	xhci_dbg(xhci, "%s() udev %s\n", __func__, dev_name(&udev->dev));
796 
797 	list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_chk_list, endpoint)
798 		destroy_sch_ep(mtk, udev, sch_ep);
799 
800 	xhci_reset_bandwidth(hcd, udev);
801 }
802 
803 int xhci_mtk_add_ep(struct usb_hcd *hcd, struct usb_device *udev,
804 		    struct usb_host_endpoint *ep)
805 {
806 	int ret;
807 
808 	ret = xhci_add_endpoint(hcd, udev, ep);
809 	if (ret)
810 		return ret;
811 
812 	if (ep->hcpriv)
813 		ret = add_ep_quirk(hcd, udev, ep);
814 
815 	return ret;
816 }
817 
818 int xhci_mtk_drop_ep(struct usb_hcd *hcd, struct usb_device *udev,
819 		     struct usb_host_endpoint *ep)
820 {
821 	int ret;
822 
823 	ret = xhci_drop_endpoint(hcd, udev, ep);
824 	if (ret)
825 		return ret;
826 
827 	if (ep->hcpriv)
828 		drop_ep_quirk(hcd, udev, ep);
829 
830 	return 0;
831 }
832