1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Thunderbolt driver - Tunneling support
4 *
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6 * Copyright (C) 2019, Intel Corporation
7 */
8
9#include <linux/delay.h>
10#include <linux/slab.h>
11#include <linux/list.h>
12
13#include "tunnel.h"
14#include "tb.h"
15
16/* PCIe adapters use always HopID of 8 for both directions */
17#define TB_PCI_HOPID			8
18
19#define TB_PCI_PATH_DOWN		0
20#define TB_PCI_PATH_UP			1
21
22/* USB3 adapters use always HopID of 8 for both directions */
23#define TB_USB3_HOPID			8
24
25#define TB_USB3_PATH_DOWN		0
26#define TB_USB3_PATH_UP			1
27
28/* DP adapters use HopID 8 for AUX and 9 for Video */
29#define TB_DP_AUX_TX_HOPID		8
30#define TB_DP_AUX_RX_HOPID		8
31#define TB_DP_VIDEO_HOPID		9
32
33#define TB_DP_VIDEO_PATH_OUT		0
34#define TB_DP_AUX_PATH_OUT		1
35#define TB_DP_AUX_PATH_IN		2
36
37#define TB_DMA_PATH_OUT			0
38#define TB_DMA_PATH_IN			1
39
40static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };
41
42#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...)                   \
43	do {                                                            \
44		struct tb_tunnel *__tunnel = (tunnel);                  \
45		level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt,   \
46		      tb_route(__tunnel->src_port->sw),                 \
47		      __tunnel->src_port->port,                         \
48		      tb_route(__tunnel->dst_port->sw),                 \
49		      __tunnel->dst_port->port,                         \
50		      tb_tunnel_names[__tunnel->type],			\
51		      ## arg);                                          \
52	} while (0)
53
54#define tb_tunnel_WARN(tunnel, fmt, arg...) \
55	__TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
56#define tb_tunnel_warn(tunnel, fmt, arg...) \
57	__TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
58#define tb_tunnel_info(tunnel, fmt, arg...) \
59	__TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
60#define tb_tunnel_dbg(tunnel, fmt, arg...) \
61	__TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
62
63static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
64					 enum tb_tunnel_type type)
65{
66	struct tb_tunnel *tunnel;
67
68	tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
69	if (!tunnel)
70		return NULL;
71
72	tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
73	if (!tunnel->paths) {
74		tb_tunnel_free(tunnel);
75		return NULL;
76	}
77
78	INIT_LIST_HEAD(&tunnel->list);
79	tunnel->tb = tb;
80	tunnel->npaths = npaths;
81	tunnel->type = type;
82
83	return tunnel;
84}
85
86static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
87{
88	int res;
89
90	res = tb_pci_port_enable(tunnel->src_port, activate);
91	if (res)
92		return res;
93
94	if (tb_port_is_pcie_up(tunnel->dst_port))
95		return tb_pci_port_enable(tunnel->dst_port, activate);
96
97	return 0;
98}
99
100static int tb_initial_credits(const struct tb_switch *sw)
101{
102	/* If the path is complete sw is not NULL */
103	if (sw) {
104		/* More credits for faster link */
105		switch (sw->link_speed * sw->link_width) {
106		case 40:
107			return 32;
108		case 20:
109			return 24;
110		}
111	}
112
113	return 16;
114}
115
116static void tb_pci_init_path(struct tb_path *path)
117{
118	path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
119	path->egress_shared_buffer = TB_PATH_NONE;
120	path->ingress_fc_enable = TB_PATH_ALL;
121	path->ingress_shared_buffer = TB_PATH_NONE;
122	path->priority = 3;
123	path->weight = 1;
124	path->drop_packages = 0;
125	path->nfc_credits = 0;
126	path->hops[0].initial_credits = 7;
127	if (path->path_length > 1)
128		path->hops[1].initial_credits =
129			tb_initial_credits(path->hops[1].in_port->sw);
130}
131
132/**
133 * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
134 * @tb: Pointer to the domain structure
135 * @down: PCIe downstream adapter
136 *
137 * If @down adapter is active, follows the tunnel to the PCIe upstream
138 * adapter and back. Returns the discovered tunnel or %NULL if there was
139 * no tunnel.
140 */
141struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
142{
143	struct tb_tunnel *tunnel;
144	struct tb_path *path;
145
146	if (!tb_pci_port_is_enabled(down))
147		return NULL;
148
149	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
150	if (!tunnel)
151		return NULL;
152
153	tunnel->activate = tb_pci_activate;
154	tunnel->src_port = down;
155
156	/*
157	 * Discover both paths even if they are not complete. We will
158	 * clean them up by calling tb_tunnel_deactivate() below in that
159	 * case.
160	 */
161	path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
162				&tunnel->dst_port, "PCIe Up");
163	if (!path) {
164		/* Just disable the downstream port */
165		tb_pci_port_enable(down, false);
166		goto err_free;
167	}
168	tunnel->paths[TB_PCI_PATH_UP] = path;
169	tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]);
170
171	path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
172				"PCIe Down");
173	if (!path)
174		goto err_deactivate;
175	tunnel->paths[TB_PCI_PATH_DOWN] = path;
176	tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]);
177
178	/* Validate that the tunnel is complete */
179	if (!tb_port_is_pcie_up(tunnel->dst_port)) {
180		tb_port_warn(tunnel->dst_port,
181			     "path does not end on a PCIe adapter, cleaning up\n");
182		goto err_deactivate;
183	}
184
185	if (down != tunnel->src_port) {
186		tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
187		goto err_deactivate;
188	}
189
190	if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
191		tb_tunnel_warn(tunnel,
192			       "tunnel is not fully activated, cleaning up\n");
193		goto err_deactivate;
194	}
195
196	tb_tunnel_dbg(tunnel, "discovered\n");
197	return tunnel;
198
199err_deactivate:
200	tb_tunnel_deactivate(tunnel);
201err_free:
202	tb_tunnel_free(tunnel);
203
204	return NULL;
205}
206
207/**
208 * tb_tunnel_alloc_pci() - allocate a pci tunnel
209 * @tb: Pointer to the domain structure
210 * @up: PCIe upstream adapter port
211 * @down: PCIe downstream adapter port
212 *
213 * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
214 * TB_TYPE_PCIE_DOWN.
215 *
216 * Return: Returns a tb_tunnel on success or NULL on failure.
217 */
218struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
219				      struct tb_port *down)
220{
221	struct tb_tunnel *tunnel;
222	struct tb_path *path;
223
224	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
225	if (!tunnel)
226		return NULL;
227
228	tunnel->activate = tb_pci_activate;
229	tunnel->src_port = down;
230	tunnel->dst_port = up;
231
232	path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
233			     "PCIe Down");
234	if (!path) {
235		tb_tunnel_free(tunnel);
236		return NULL;
237	}
238	tb_pci_init_path(path);
239	tunnel->paths[TB_PCI_PATH_DOWN] = path;
240
241	path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
242			     "PCIe Up");
243	if (!path) {
244		tb_tunnel_free(tunnel);
245		return NULL;
246	}
247	tb_pci_init_path(path);
248	tunnel->paths[TB_PCI_PATH_UP] = path;
249
250	return tunnel;
251}
252
253static bool tb_dp_is_usb4(const struct tb_switch *sw)
254{
255	/* Titan Ridge DP adapters need the same treatment as USB4 */
256	return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
257}
258
259static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
260{
261	int timeout = 10;
262	u32 val;
263	int ret;
264
265	/* Both ends need to support this */
266	if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
267		return 0;
268
269	ret = tb_port_read(out, &val, TB_CFG_PORT,
270			   out->cap_adap + DP_STATUS_CTRL, 1);
271	if (ret)
272		return ret;
273
274	val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;
275
276	ret = tb_port_write(out, &val, TB_CFG_PORT,
277			    out->cap_adap + DP_STATUS_CTRL, 1);
278	if (ret)
279		return ret;
280
281	do {
282		ret = tb_port_read(out, &val, TB_CFG_PORT,
283				   out->cap_adap + DP_STATUS_CTRL, 1);
284		if (ret)
285			return ret;
286		if (!(val & DP_STATUS_CTRL_CMHS))
287			return 0;
288		usleep_range(10, 100);
289	} while (timeout--);
290
291	return -ETIMEDOUT;
292}
293
294static inline u32 tb_dp_cap_get_rate(u32 val)
295{
296	u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;
297
298	switch (rate) {
299	case DP_COMMON_CAP_RATE_RBR:
300		return 1620;
301	case DP_COMMON_CAP_RATE_HBR:
302		return 2700;
303	case DP_COMMON_CAP_RATE_HBR2:
304		return 5400;
305	case DP_COMMON_CAP_RATE_HBR3:
306		return 8100;
307	default:
308		return 0;
309	}
310}
311
312static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
313{
314	val &= ~DP_COMMON_CAP_RATE_MASK;
315	switch (rate) {
316	default:
317		WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
318		fallthrough;
319	case 1620:
320		val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
321		break;
322	case 2700:
323		val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
324		break;
325	case 5400:
326		val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
327		break;
328	case 8100:
329		val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
330		break;
331	}
332	return val;
333}
334
335static inline u32 tb_dp_cap_get_lanes(u32 val)
336{
337	u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;
338
339	switch (lanes) {
340	case DP_COMMON_CAP_1_LANE:
341		return 1;
342	case DP_COMMON_CAP_2_LANES:
343		return 2;
344	case DP_COMMON_CAP_4_LANES:
345		return 4;
346	default:
347		return 0;
348	}
349}
350
351static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
352{
353	val &= ~DP_COMMON_CAP_LANES_MASK;
354	switch (lanes) {
355	default:
356		WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
357		     lanes);
358		fallthrough;
359	case 1:
360		val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
361		break;
362	case 2:
363		val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
364		break;
365	case 4:
366		val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
367		break;
368	}
369	return val;
370}
371
372static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
373{
374	/* Tunneling removes the DP 8b/10b encoding */
375	return rate * lanes * 8 / 10;
376}
377
378static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes,
379				  u32 out_rate, u32 out_lanes, u32 *new_rate,
380				  u32 *new_lanes)
381{
382	static const u32 dp_bw[][2] = {
383		/* Mb/s, lanes */
384		{ 8100, 4 }, /* 25920 Mb/s */
385		{ 5400, 4 }, /* 17280 Mb/s */
386		{ 8100, 2 }, /* 12960 Mb/s */
387		{ 2700, 4 }, /* 8640 Mb/s */
388		{ 5400, 2 }, /* 8640 Mb/s */
389		{ 8100, 1 }, /* 6480 Mb/s */
390		{ 1620, 4 }, /* 5184 Mb/s */
391		{ 5400, 1 }, /* 4320 Mb/s */
392		{ 2700, 2 }, /* 4320 Mb/s */
393		{ 1620, 2 }, /* 2592 Mb/s */
394		{ 2700, 1 }, /* 2160 Mb/s */
395		{ 1620, 1 }, /* 1296 Mb/s */
396	};
397	unsigned int i;
398
399	/*
400	 * Find a combination that can fit into max_bw and does not
401	 * exceed the maximum rate and lanes supported by the DP OUT and
402	 * DP IN adapters.
403	 */
404	for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
405		if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
406			continue;
407
408		if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
409			continue;
410
411		if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
412			*new_rate = dp_bw[i][0];
413			*new_lanes = dp_bw[i][1];
414			return 0;
415		}
416	}
417
418	return -ENOSR;
419}
420
421static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
422{
423	u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
424	struct tb_port *out = tunnel->dst_port;
425	struct tb_port *in = tunnel->src_port;
426	int ret, max_bw;
427
428	/*
429	 * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
430	 * newer generation hardware.
431	 */
432	if (in->sw->generation < 2 || out->sw->generation < 2)
433		return 0;
434
435	/*
436	 * Perform connection manager handshake between IN and OUT ports
437	 * before capabilities exchange can take place.
438	 */
439	ret = tb_dp_cm_handshake(in, out);
440	if (ret)
441		return ret;
442
443	/* Read both DP_LOCAL_CAP registers */
444	ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
445			   in->cap_adap + DP_LOCAL_CAP, 1);
446	if (ret)
447		return ret;
448
449	ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
450			   out->cap_adap + DP_LOCAL_CAP, 1);
451	if (ret)
452		return ret;
453
454	/* Write IN local caps to OUT remote caps */
455	ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
456			    out->cap_adap + DP_REMOTE_CAP, 1);
457	if (ret)
458		return ret;
459
460	in_rate = tb_dp_cap_get_rate(in_dp_cap);
461	in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
462	tb_port_dbg(in, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
463		    in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));
464
465	/*
466	 * If the tunnel bandwidth is limited (max_bw is set) then see
467	 * if we need to reduce bandwidth to fit there.
468	 */
469	out_rate = tb_dp_cap_get_rate(out_dp_cap);
470	out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
471	bw = tb_dp_bandwidth(out_rate, out_lanes);
472	tb_port_dbg(out, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
473		    out_rate, out_lanes, bw);
474
475	if (in->sw->config.depth < out->sw->config.depth)
476		max_bw = tunnel->max_down;
477	else
478		max_bw = tunnel->max_up;
479
480	if (max_bw && bw > max_bw) {
481		u32 new_rate, new_lanes, new_bw;
482
483		ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes,
484					     out_rate, out_lanes, &new_rate,
485					     &new_lanes);
486		if (ret) {
487			tb_port_info(out, "not enough bandwidth for DP tunnel\n");
488			return ret;
489		}
490
491		new_bw = tb_dp_bandwidth(new_rate, new_lanes);
492		tb_port_dbg(out, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
493			    new_rate, new_lanes, new_bw);
494
495		/*
496		 * Set new rate and number of lanes before writing it to
497		 * the IN port remote caps.
498		 */
499		out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
500		out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
501	}
502
503	return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
504			     in->cap_adap + DP_REMOTE_CAP, 1);
505}
506
507static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
508{
509	int ret;
510
511	if (active) {
512		struct tb_path **paths;
513		int last;
514
515		paths = tunnel->paths;
516		last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
517
518		tb_dp_port_set_hops(tunnel->src_port,
519			paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
520			paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
521			paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
522
523		tb_dp_port_set_hops(tunnel->dst_port,
524			paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
525			paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
526			paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
527	} else {
528		tb_dp_port_hpd_clear(tunnel->src_port);
529		tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
530		if (tb_port_is_dpout(tunnel->dst_port))
531			tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
532	}
533
534	ret = tb_dp_port_enable(tunnel->src_port, active);
535	if (ret)
536		return ret;
537
538	if (tb_port_is_dpout(tunnel->dst_port))
539		return tb_dp_port_enable(tunnel->dst_port, active);
540
541	return 0;
542}
543
544static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
545				    int *consumed_down)
546{
547	struct tb_port *in = tunnel->src_port;
548	const struct tb_switch *sw = in->sw;
549	u32 val, rate = 0, lanes = 0;
550	int ret;
551
552	if (tb_dp_is_usb4(sw)) {
553		int timeout = 20;
554
555		/*
556		 * Wait for DPRX done. Normally it should be already set
557		 * for active tunnel.
558		 */
559		do {
560			ret = tb_port_read(in, &val, TB_CFG_PORT,
561					   in->cap_adap + DP_COMMON_CAP, 1);
562			if (ret)
563				return ret;
564
565			if (val & DP_COMMON_CAP_DPRX_DONE) {
566				rate = tb_dp_cap_get_rate(val);
567				lanes = tb_dp_cap_get_lanes(val);
568				break;
569			}
570			msleep(250);
571		} while (timeout--);
572
573		if (!timeout)
574			return -ETIMEDOUT;
575	} else if (sw->generation >= 2) {
576		/*
577		 * Read from the copied remote cap so that we take into
578		 * account if capabilities were reduced during exchange.
579		 */
580		ret = tb_port_read(in, &val, TB_CFG_PORT,
581				   in->cap_adap + DP_REMOTE_CAP, 1);
582		if (ret)
583			return ret;
584
585		rate = tb_dp_cap_get_rate(val);
586		lanes = tb_dp_cap_get_lanes(val);
587	} else {
588		/* No bandwidth management for legacy devices  */
589		*consumed_up = 0;
590		*consumed_down = 0;
591		return 0;
592	}
593
594	if (in->sw->config.depth < tunnel->dst_port->sw->config.depth) {
595		*consumed_up = 0;
596		*consumed_down = tb_dp_bandwidth(rate, lanes);
597	} else {
598		*consumed_up = tb_dp_bandwidth(rate, lanes);
599		*consumed_down = 0;
600	}
601
602	return 0;
603}
604
605static void tb_dp_init_aux_path(struct tb_path *path)
606{
607	int i;
608
609	path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
610	path->egress_shared_buffer = TB_PATH_NONE;
611	path->ingress_fc_enable = TB_PATH_ALL;
612	path->ingress_shared_buffer = TB_PATH_NONE;
613	path->priority = 2;
614	path->weight = 1;
615
616	for (i = 0; i < path->path_length; i++)
617		path->hops[i].initial_credits = 1;
618}
619
620static void tb_dp_init_video_path(struct tb_path *path, bool discover)
621{
622	u32 nfc_credits = path->hops[0].in_port->config.nfc_credits;
623
624	path->egress_fc_enable = TB_PATH_NONE;
625	path->egress_shared_buffer = TB_PATH_NONE;
626	path->ingress_fc_enable = TB_PATH_NONE;
627	path->ingress_shared_buffer = TB_PATH_NONE;
628	path->priority = 1;
629	path->weight = 1;
630
631	if (discover) {
632		path->nfc_credits = nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
633	} else {
634		u32 max_credits;
635
636		max_credits = (nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
637			ADP_CS_4_TOTAL_BUFFERS_SHIFT;
638		/* Leave some credits for AUX path */
639		path->nfc_credits = min(max_credits - 2, 12U);
640	}
641}
642
643/**
644 * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
645 * @tb: Pointer to the domain structure
646 * @in: DP in adapter
647 *
648 * If @in adapter is active, follows the tunnel to the DP out adapter
649 * and back. Returns the discovered tunnel or %NULL if there was no
650 * tunnel.
651 *
652 * Return: DP tunnel or %NULL if no tunnel found.
653 */
654struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
655{
656	struct tb_tunnel *tunnel;
657	struct tb_port *port;
658	struct tb_path *path;
659
660	if (!tb_dp_port_is_enabled(in))
661		return NULL;
662
663	tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
664	if (!tunnel)
665		return NULL;
666
667	tunnel->init = tb_dp_xchg_caps;
668	tunnel->activate = tb_dp_activate;
669	tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
670	tunnel->src_port = in;
671
672	path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
673				&tunnel->dst_port, "Video");
674	if (!path) {
675		/* Just disable the DP IN port */
676		tb_dp_port_enable(in, false);
677		goto err_free;
678	}
679	tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
680	tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], true);
681
682	path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
683	if (!path)
684		goto err_deactivate;
685	tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
686	tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
687
688	path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
689				&port, "AUX RX");
690	if (!path)
691		goto err_deactivate;
692	tunnel->paths[TB_DP_AUX_PATH_IN] = path;
693	tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);
694
695	/* Validate that the tunnel is complete */
696	if (!tb_port_is_dpout(tunnel->dst_port)) {
697		tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
698		goto err_deactivate;
699	}
700
701	if (!tb_dp_port_is_enabled(tunnel->dst_port))
702		goto err_deactivate;
703
704	if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
705		goto err_deactivate;
706
707	if (port != tunnel->src_port) {
708		tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
709		goto err_deactivate;
710	}
711
712	tb_tunnel_dbg(tunnel, "discovered\n");
713	return tunnel;
714
715err_deactivate:
716	tb_tunnel_deactivate(tunnel);
717err_free:
718	tb_tunnel_free(tunnel);
719
720	return NULL;
721}
722
723/**
724 * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
725 * @tb: Pointer to the domain structure
726 * @in: DP in adapter port
727 * @out: DP out adapter port
728 * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0
729 *	    if not limited)
730 * @max_down: Maximum available downstream bandwidth for the DP tunnel
731 *	      (%0 if not limited)
732 *
733 * Allocates a tunnel between @in and @out that is capable of tunneling
734 * Display Port traffic.
735 *
736 * Return: Returns a tb_tunnel on success or NULL on failure.
737 */
738struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
739				     struct tb_port *out, int max_up,
740				     int max_down)
741{
742	struct tb_tunnel *tunnel;
743	struct tb_path **paths;
744	struct tb_path *path;
745
746	if (WARN_ON(!in->cap_adap || !out->cap_adap))
747		return NULL;
748
749	tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
750	if (!tunnel)
751		return NULL;
752
753	tunnel->init = tb_dp_xchg_caps;
754	tunnel->activate = tb_dp_activate;
755	tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
756	tunnel->src_port = in;
757	tunnel->dst_port = out;
758	tunnel->max_up = max_up;
759	tunnel->max_down = max_down;
760
761	paths = tunnel->paths;
762
763	path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
764			     1, "Video");
765	if (!path)
766		goto err_free;
767	tb_dp_init_video_path(path, false);
768	paths[TB_DP_VIDEO_PATH_OUT] = path;
769
770	path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
771			     TB_DP_AUX_TX_HOPID, 1, "AUX TX");
772	if (!path)
773		goto err_free;
774	tb_dp_init_aux_path(path);
775	paths[TB_DP_AUX_PATH_OUT] = path;
776
777	path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
778			     TB_DP_AUX_RX_HOPID, 1, "AUX RX");
779	if (!path)
780		goto err_free;
781	tb_dp_init_aux_path(path);
782	paths[TB_DP_AUX_PATH_IN] = path;
783
784	return tunnel;
785
786err_free:
787	tb_tunnel_free(tunnel);
788	return NULL;
789}
790
791static u32 tb_dma_credits(struct tb_port *nhi)
792{
793	u32 max_credits;
794
795	max_credits = (nhi->config.nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
796		ADP_CS_4_TOTAL_BUFFERS_SHIFT;
797	return min(max_credits, 13U);
798}
799
800static int tb_dma_activate(struct tb_tunnel *tunnel, bool active)
801{
802	struct tb_port *nhi = tunnel->src_port;
803	u32 credits;
804
805	credits = active ? tb_dma_credits(nhi) : 0;
806	return tb_port_set_initial_credits(nhi, credits);
807}
808
809static void tb_dma_init_path(struct tb_path *path, unsigned int isb,
810			     unsigned int efc, u32 credits)
811{
812	int i;
813
814	path->egress_fc_enable = efc;
815	path->ingress_fc_enable = TB_PATH_ALL;
816	path->egress_shared_buffer = TB_PATH_NONE;
817	path->ingress_shared_buffer = isb;
818	path->priority = 5;
819	path->weight = 1;
820	path->clear_fc = true;
821
822	for (i = 0; i < path->path_length; i++)
823		path->hops[i].initial_credits = credits;
824}
825
826/**
827 * tb_tunnel_alloc_dma() - allocate a DMA tunnel
828 * @tb: Pointer to the domain structure
829 * @nhi: Host controller port
830 * @dst: Destination null port which the other domain is connected to
831 * @transmit_ring: NHI ring number used to send packets towards the
832 *		   other domain
833 * @transmit_path: HopID used for transmitting packets
834 * @receive_ring: NHI ring number used to receive packets from the
835 *		  other domain
836 * @reveive_path: HopID used for receiving packets
837 *
838 * Return: Returns a tb_tunnel on success or NULL on failure.
839 */
840struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
841				      struct tb_port *dst, int transmit_ring,
842				      int transmit_path, int receive_ring,
843				      int receive_path)
844{
845	struct tb_tunnel *tunnel;
846	struct tb_path *path;
847	u32 credits;
848
849	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);
850	if (!tunnel)
851		return NULL;
852
853	tunnel->activate = tb_dma_activate;
854	tunnel->src_port = nhi;
855	tunnel->dst_port = dst;
856
857	credits = tb_dma_credits(nhi);
858
859	path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX");
860	if (!path) {
861		tb_tunnel_free(tunnel);
862		return NULL;
863	}
864	tb_dma_init_path(path, TB_PATH_NONE, TB_PATH_SOURCE | TB_PATH_INTERNAL,
865			 credits);
866	tunnel->paths[TB_DMA_PATH_IN] = path;
867
868	path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX");
869	if (!path) {
870		tb_tunnel_free(tunnel);
871		return NULL;
872	}
873	tb_dma_init_path(path, TB_PATH_SOURCE, TB_PATH_ALL, credits);
874	tunnel->paths[TB_DMA_PATH_OUT] = path;
875
876	return tunnel;
877}
878
879static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down)
880{
881	int ret, up_max_rate, down_max_rate;
882
883	ret = usb4_usb3_port_max_link_rate(up);
884	if (ret < 0)
885		return ret;
886	up_max_rate = ret;
887
888	ret = usb4_usb3_port_max_link_rate(down);
889	if (ret < 0)
890		return ret;
891	down_max_rate = ret;
892
893	return min(up_max_rate, down_max_rate);
894}
895
896static int tb_usb3_init(struct tb_tunnel *tunnel)
897{
898	tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n",
899		      tunnel->allocated_up, tunnel->allocated_down);
900
901	return usb4_usb3_port_allocate_bandwidth(tunnel->src_port,
902						 &tunnel->allocated_up,
903						 &tunnel->allocated_down);
904}
905
906static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate)
907{
908	int res;
909
910	res = tb_usb3_port_enable(tunnel->src_port, activate);
911	if (res)
912		return res;
913
914	if (tb_port_is_usb3_up(tunnel->dst_port))
915		return tb_usb3_port_enable(tunnel->dst_port, activate);
916
917	return 0;
918}
919
920static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel,
921		int *consumed_up, int *consumed_down)
922{
923	/*
924	 * PCIe tunneling affects the USB3 bandwidth so take that it
925	 * into account here.
926	 */
927	*consumed_up = tunnel->allocated_up * (3 + 1) / 3;
928	*consumed_down = tunnel->allocated_down * (3 + 1) / 3;
929	return 0;
930}
931
932static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel)
933{
934	int ret;
935
936	ret = usb4_usb3_port_release_bandwidth(tunnel->src_port,
937					       &tunnel->allocated_up,
938					       &tunnel->allocated_down);
939	if (ret)
940		return ret;
941
942	tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n",
943		      tunnel->allocated_up, tunnel->allocated_down);
944	return 0;
945}
946
947static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
948						int *available_up,
949						int *available_down)
950{
951	int ret, max_rate, allocate_up, allocate_down;
952
953	ret = usb4_usb3_port_actual_link_rate(tunnel->src_port);
954	if (ret < 0) {
955		tb_tunnel_warn(tunnel, "failed to read actual link rate\n");
956		return;
957	} else if (!ret) {
958		/* Use maximum link rate if the link valid is not set */
959		ret = tb_usb3_max_link_rate(tunnel->dst_port, tunnel->src_port);
960		if (ret < 0) {
961			tb_tunnel_warn(tunnel, "failed to read maximum link rate\n");
962			return;
963		}
964	}
965
966	/*
967	 * 90% of the max rate can be allocated for isochronous
968	 * transfers.
969	 */
970	max_rate = ret * 90 / 100;
971
972	/* No need to reclaim if already at maximum */
973	if (tunnel->allocated_up >= max_rate &&
974	    tunnel->allocated_down >= max_rate)
975		return;
976
977	/* Don't go lower than what is already allocated */
978	allocate_up = min(max_rate, *available_up);
979	if (allocate_up < tunnel->allocated_up)
980		allocate_up = tunnel->allocated_up;
981
982	allocate_down = min(max_rate, *available_down);
983	if (allocate_down < tunnel->allocated_down)
984		allocate_down = tunnel->allocated_down;
985
986	/* If no changes no need to do more */
987	if (allocate_up == tunnel->allocated_up &&
988	    allocate_down == tunnel->allocated_down)
989		return;
990
991	ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up,
992						&allocate_down);
993	if (ret) {
994		tb_tunnel_info(tunnel, "failed to allocate bandwidth\n");
995		return;
996	}
997
998	tunnel->allocated_up = allocate_up;
999	*available_up -= tunnel->allocated_up;
1000
1001	tunnel->allocated_down = allocate_down;
1002	*available_down -= tunnel->allocated_down;
1003
1004	tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n",
1005		      tunnel->allocated_up, tunnel->allocated_down);
1006}
1007
1008static void tb_usb3_init_path(struct tb_path *path)
1009{
1010	path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1011	path->egress_shared_buffer = TB_PATH_NONE;
1012	path->ingress_fc_enable = TB_PATH_ALL;
1013	path->ingress_shared_buffer = TB_PATH_NONE;
1014	path->priority = 3;
1015	path->weight = 3;
1016	path->drop_packages = 0;
1017	path->nfc_credits = 0;
1018	path->hops[0].initial_credits = 7;
1019	if (path->path_length > 1)
1020		path->hops[1].initial_credits =
1021			tb_initial_credits(path->hops[1].in_port->sw);
1022}
1023
1024/**
1025 * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
1026 * @tb: Pointer to the domain structure
1027 * @down: USB3 downstream adapter
1028 *
1029 * If @down adapter is active, follows the tunnel to the USB3 upstream
1030 * adapter and back. Returns the discovered tunnel or %NULL if there was
1031 * no tunnel.
1032 */
1033struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
1034{
1035	struct tb_tunnel *tunnel;
1036	struct tb_path *path;
1037
1038	if (!tb_usb3_port_is_enabled(down))
1039		return NULL;
1040
1041	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1042	if (!tunnel)
1043		return NULL;
1044
1045	tunnel->activate = tb_usb3_activate;
1046	tunnel->src_port = down;
1047
1048	/*
1049	 * Discover both paths even if they are not complete. We will
1050	 * clean them up by calling tb_tunnel_deactivate() below in that
1051	 * case.
1052	 */
1053	path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
1054				&tunnel->dst_port, "USB3 Down");
1055	if (!path) {
1056		/* Just disable the downstream port */
1057		tb_usb3_port_enable(down, false);
1058		goto err_free;
1059	}
1060	tunnel->paths[TB_USB3_PATH_DOWN] = path;
1061	tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
1062
1063	path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
1064				"USB3 Up");
1065	if (!path)
1066		goto err_deactivate;
1067	tunnel->paths[TB_USB3_PATH_UP] = path;
1068	tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]);
1069
1070	/* Validate that the tunnel is complete */
1071	if (!tb_port_is_usb3_up(tunnel->dst_port)) {
1072		tb_port_warn(tunnel->dst_port,
1073			     "path does not end on an USB3 adapter, cleaning up\n");
1074		goto err_deactivate;
1075	}
1076
1077	if (down != tunnel->src_port) {
1078		tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
1079		goto err_deactivate;
1080	}
1081
1082	if (!tb_usb3_port_is_enabled(tunnel->dst_port)) {
1083		tb_tunnel_warn(tunnel,
1084			       "tunnel is not fully activated, cleaning up\n");
1085		goto err_deactivate;
1086	}
1087
1088	if (!tb_route(down->sw)) {
1089		int ret;
1090
1091		/*
1092		 * Read the initial bandwidth allocation for the first
1093		 * hop tunnel.
1094		 */
1095		ret = usb4_usb3_port_allocated_bandwidth(down,
1096			&tunnel->allocated_up, &tunnel->allocated_down);
1097		if (ret)
1098			goto err_deactivate;
1099
1100		tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n",
1101			      tunnel->allocated_up, tunnel->allocated_down);
1102
1103		tunnel->init = tb_usb3_init;
1104		tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1105		tunnel->release_unused_bandwidth =
1106			tb_usb3_release_unused_bandwidth;
1107		tunnel->reclaim_available_bandwidth =
1108			tb_usb3_reclaim_available_bandwidth;
1109	}
1110
1111	tb_tunnel_dbg(tunnel, "discovered\n");
1112	return tunnel;
1113
1114err_deactivate:
1115	tb_tunnel_deactivate(tunnel);
1116err_free:
1117	tb_tunnel_free(tunnel);
1118
1119	return NULL;
1120}
1121
1122/**
1123 * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel
1124 * @tb: Pointer to the domain structure
1125 * @up: USB3 upstream adapter port
1126 * @down: USB3 downstream adapter port
1127 * @max_up: Maximum available upstream bandwidth for the USB3 tunnel (%0
1128 *	    if not limited).
1129 * @max_down: Maximum available downstream bandwidth for the USB3 tunnel
1130 *	      (%0 if not limited).
1131 *
1132 * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and
1133 * @TB_TYPE_USB3_DOWN.
1134 *
1135 * Return: Returns a tb_tunnel on success or %NULL on failure.
1136 */
1137struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
1138				       struct tb_port *down, int max_up,
1139				       int max_down)
1140{
1141	struct tb_tunnel *tunnel;
1142	struct tb_path *path;
1143	int max_rate = 0;
1144
1145	/*
1146	 * Check that we have enough bandwidth available for the new
1147	 * USB3 tunnel.
1148	 */
1149	if (max_up > 0 || max_down > 0) {
1150		max_rate = tb_usb3_max_link_rate(down, up);
1151		if (max_rate < 0)
1152			return NULL;
1153
1154		/* Only 90% can be allocated for USB3 isochronous transfers */
1155		max_rate = max_rate * 90 / 100;
1156		tb_port_dbg(up, "required bandwidth for USB3 tunnel %d Mb/s\n",
1157			    max_rate);
1158
1159		if (max_rate > max_up || max_rate > max_down) {
1160			tb_port_warn(up, "not enough bandwidth for USB3 tunnel\n");
1161			return NULL;
1162		}
1163	}
1164
1165	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1166	if (!tunnel)
1167		return NULL;
1168
1169	tunnel->activate = tb_usb3_activate;
1170	tunnel->src_port = down;
1171	tunnel->dst_port = up;
1172	tunnel->max_up = max_up;
1173	tunnel->max_down = max_down;
1174
1175	path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0,
1176			     "USB3 Down");
1177	if (!path) {
1178		tb_tunnel_free(tunnel);
1179		return NULL;
1180	}
1181	tb_usb3_init_path(path);
1182	tunnel->paths[TB_USB3_PATH_DOWN] = path;
1183
1184	path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0,
1185			     "USB3 Up");
1186	if (!path) {
1187		tb_tunnel_free(tunnel);
1188		return NULL;
1189	}
1190	tb_usb3_init_path(path);
1191	tunnel->paths[TB_USB3_PATH_UP] = path;
1192
1193	if (!tb_route(down->sw)) {
1194		tunnel->allocated_up = max_rate;
1195		tunnel->allocated_down = max_rate;
1196
1197		tunnel->init = tb_usb3_init;
1198		tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1199		tunnel->release_unused_bandwidth =
1200			tb_usb3_release_unused_bandwidth;
1201		tunnel->reclaim_available_bandwidth =
1202			tb_usb3_reclaim_available_bandwidth;
1203	}
1204
1205	return tunnel;
1206}
1207
1208/**
1209 * tb_tunnel_free() - free a tunnel
1210 * @tunnel: Tunnel to be freed
1211 *
1212 * Frees a tunnel. The tunnel does not need to be deactivated.
1213 */
1214void tb_tunnel_free(struct tb_tunnel *tunnel)
1215{
1216	int i;
1217
1218	if (!tunnel)
1219		return;
1220
1221	for (i = 0; i < tunnel->npaths; i++) {
1222		if (tunnel->paths[i])
1223			tb_path_free(tunnel->paths[i]);
1224	}
1225
1226	kfree(tunnel->paths);
1227	kfree(tunnel);
1228}
1229
1230/**
1231 * tb_tunnel_is_invalid - check whether an activated path is still valid
1232 * @tunnel: Tunnel to check
1233 */
1234bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
1235{
1236	int i;
1237
1238	for (i = 0; i < tunnel->npaths; i++) {
1239		WARN_ON(!tunnel->paths[i]->activated);
1240		if (tb_path_is_invalid(tunnel->paths[i]))
1241			return true;
1242	}
1243
1244	return false;
1245}
1246
1247/**
1248 * tb_tunnel_restart() - activate a tunnel after a hardware reset
1249 * @tunnel: Tunnel to restart
1250 *
1251 * Return: 0 on success and negative errno in case if failure
1252 */
1253int tb_tunnel_restart(struct tb_tunnel *tunnel)
1254{
1255	int res, i;
1256
1257	tb_tunnel_dbg(tunnel, "activating\n");
1258
1259	/*
1260	 * Make sure all paths are properly disabled before enabling
1261	 * them again.
1262	 */
1263	for (i = 0; i < tunnel->npaths; i++) {
1264		if (tunnel->paths[i]->activated) {
1265			tb_path_deactivate(tunnel->paths[i]);
1266			tunnel->paths[i]->activated = false;
1267		}
1268	}
1269
1270	if (tunnel->init) {
1271		res = tunnel->init(tunnel);
1272		if (res)
1273			return res;
1274	}
1275
1276	for (i = 0; i < tunnel->npaths; i++) {
1277		res = tb_path_activate(tunnel->paths[i]);
1278		if (res)
1279			goto err;
1280	}
1281
1282	if (tunnel->activate) {
1283		res = tunnel->activate(tunnel, true);
1284		if (res)
1285			goto err;
1286	}
1287
1288	return 0;
1289
1290err:
1291	tb_tunnel_warn(tunnel, "activation failed\n");
1292	tb_tunnel_deactivate(tunnel);
1293	return res;
1294}
1295
1296/**
1297 * tb_tunnel_activate() - activate a tunnel
1298 * @tunnel: Tunnel to activate
1299 *
1300 * Return: Returns 0 on success or an error code on failure.
1301 */
1302int tb_tunnel_activate(struct tb_tunnel *tunnel)
1303{
1304	int i;
1305
1306	for (i = 0; i < tunnel->npaths; i++) {
1307		if (tunnel->paths[i]->activated) {
1308			tb_tunnel_WARN(tunnel,
1309				       "trying to activate an already activated tunnel\n");
1310			return -EINVAL;
1311		}
1312	}
1313
1314	return tb_tunnel_restart(tunnel);
1315}
1316
1317/**
1318 * tb_tunnel_deactivate() - deactivate a tunnel
1319 * @tunnel: Tunnel to deactivate
1320 */
1321void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
1322{
1323	int i;
1324
1325	tb_tunnel_dbg(tunnel, "deactivating\n");
1326
1327	if (tunnel->activate)
1328		tunnel->activate(tunnel, false);
1329
1330	for (i = 0; i < tunnel->npaths; i++) {
1331		if (tunnel->paths[i] && tunnel->paths[i]->activated)
1332			tb_path_deactivate(tunnel->paths[i]);
1333	}
1334}
1335
1336/**
1337 * tb_tunnel_port_on_path() - Does the tunnel go through port
1338 * @tunnel: Tunnel to check
1339 * @port: Port to check
1340 *
1341 * Returns true if @tunnel goes through @port (direction does not matter),
1342 * false otherwise.
1343 */
1344bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
1345			    const struct tb_port *port)
1346{
1347	int i;
1348
1349	for (i = 0; i < tunnel->npaths; i++) {
1350		if (!tunnel->paths[i])
1351			continue;
1352
1353		if (tb_path_port_on_path(tunnel->paths[i], port))
1354			return true;
1355	}
1356
1357	return false;
1358}
1359
1360static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
1361{
1362	int i;
1363
1364	for (i = 0; i < tunnel->npaths; i++) {
1365		if (!tunnel->paths[i])
1366			return false;
1367		if (!tunnel->paths[i]->activated)
1368			return false;
1369	}
1370
1371	return true;
1372}
1373
1374/**
1375 * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
1376 * @tunnel: Tunnel to check
1377 * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port.
1378 *		 Can be %NULL.
1379 * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port.
1380 *		   Can be %NULL.
1381 *
1382 * Stores the amount of isochronous bandwidth @tunnel consumes in
1383 * @consumed_up and @consumed_down. In case of success returns %0,
1384 * negative errno otherwise.
1385 */
1386int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
1387				 int *consumed_down)
1388{
1389	int up_bw = 0, down_bw = 0;
1390
1391	if (!tb_tunnel_is_active(tunnel))
1392		goto out;
1393
1394	if (tunnel->consumed_bandwidth) {
1395		int ret;
1396
1397		ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw);
1398		if (ret)
1399			return ret;
1400
1401		tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw,
1402			      down_bw);
1403	}
1404
1405out:
1406	if (consumed_up)
1407		*consumed_up = up_bw;
1408	if (consumed_down)
1409		*consumed_down = down_bw;
1410
1411	return 0;
1412}
1413
1414/**
1415 * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth
1416 * @tunnel: Tunnel whose unused bandwidth to release
1417 *
1418 * If tunnel supports dynamic bandwidth management (USB3 tunnels at the
1419 * moment) this function makes it to release all the unused bandwidth.
1420 *
1421 * Returns %0 in case of success and negative errno otherwise.
1422 */
1423int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel)
1424{
1425	if (!tb_tunnel_is_active(tunnel))
1426		return 0;
1427
1428	if (tunnel->release_unused_bandwidth) {
1429		int ret;
1430
1431		ret = tunnel->release_unused_bandwidth(tunnel);
1432		if (ret)
1433			return ret;
1434	}
1435
1436	return 0;
1437}
1438
1439/**
1440 * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth
1441 * @tunnel: Tunnel reclaiming available bandwidth
1442 * @available_up: Available upstream bandwidth (in Mb/s)
1443 * @available_down: Available downstream bandwidth (in Mb/s)
1444 *
1445 * Reclaims bandwidth from @available_up and @available_down and updates
1446 * the variables accordingly (e.g decreases both according to what was
1447 * reclaimed by the tunnel). If nothing was reclaimed the values are
1448 * kept as is.
1449 */
1450void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
1451					   int *available_up,
1452					   int *available_down)
1453{
1454	if (!tb_tunnel_is_active(tunnel))
1455		return;
1456
1457	if (tunnel->reclaim_available_bandwidth)
1458		tunnel->reclaim_available_bandwidth(tunnel, available_up,
1459						    available_down);
1460}
1461