1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Thunderbolt driver - bus logic (NHI independent)
4  *
5  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6  * Copyright (C) 2019, Intel Corporation
7  */
8 
9 #include <linux/slab.h>
10 #include <linux/errno.h>
11 #include <linux/delay.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/platform_data/x86/apple.h>
14 
15 #include "tb.h"
16 #include "tb_regs.h"
17 #include "tunnel.h"
18 
19 #define TB_TIMEOUT	100	/* ms */
20 #define MAX_GROUPS	7	/* max Group_ID is 7 */
21 
22 /**
23  * struct tb_cm - Simple Thunderbolt connection manager
24  * @tunnel_list: List of active tunnels
25  * @dp_resources: List of available DP resources for DP tunneling
26  * @hotplug_active: tb_handle_hotplug will stop progressing plug
27  *		    events and exit if this is not set (it needs to
28  *		    acquire the lock one more time). Used to drain wq
29  *		    after cfg has been paused.
30  * @remove_work: Work used to remove any unplugged routers after
31  *		 runtime resume
32  * @groups: Bandwidth groups used in this domain.
33  */
34 struct tb_cm {
35 	struct list_head tunnel_list;
36 	struct list_head dp_resources;
37 	bool hotplug_active;
38 	struct delayed_work remove_work;
39 	struct tb_bandwidth_group groups[MAX_GROUPS];
40 };
41 
tcm_to_tb(struct tb_cm * tcm)42 static inline struct tb *tcm_to_tb(struct tb_cm *tcm)
43 {
44 	return ((void *)tcm - sizeof(struct tb));
45 }
46 
47 struct tb_hotplug_event {
48 	struct work_struct work;
49 	struct tb *tb;
50 	u64 route;
51 	u8 port;
52 	bool unplug;
53 };
54 
tb_init_bandwidth_groups(struct tb_cm * tcm)55 static void tb_init_bandwidth_groups(struct tb_cm *tcm)
56 {
57 	int i;
58 
59 	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
60 		struct tb_bandwidth_group *group = &tcm->groups[i];
61 
62 		group->tb = tcm_to_tb(tcm);
63 		group->index = i + 1;
64 		INIT_LIST_HEAD(&group->ports);
65 	}
66 }
67 
tb_bandwidth_group_attach_port(struct tb_bandwidth_group * group,struct tb_port * in)68 static void tb_bandwidth_group_attach_port(struct tb_bandwidth_group *group,
69 					   struct tb_port *in)
70 {
71 	if (!group || WARN_ON(in->group))
72 		return;
73 
74 	in->group = group;
75 	list_add_tail(&in->group_list, &group->ports);
76 
77 	tb_port_dbg(in, "attached to bandwidth group %d\n", group->index);
78 }
79 
tb_find_free_bandwidth_group(struct tb_cm * tcm)80 static struct tb_bandwidth_group *tb_find_free_bandwidth_group(struct tb_cm *tcm)
81 {
82 	int i;
83 
84 	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
85 		struct tb_bandwidth_group *group = &tcm->groups[i];
86 
87 		if (list_empty(&group->ports))
88 			return group;
89 	}
90 
91 	return NULL;
92 }
93 
94 static struct tb_bandwidth_group *
tb_attach_bandwidth_group(struct tb_cm * tcm,struct tb_port * in,struct tb_port * out)95 tb_attach_bandwidth_group(struct tb_cm *tcm, struct tb_port *in,
96 			  struct tb_port *out)
97 {
98 	struct tb_bandwidth_group *group;
99 	struct tb_tunnel *tunnel;
100 
101 	/*
102 	 * Find all DP tunnels that go through all the same USB4 links
103 	 * as this one. Because we always setup tunnels the same way we
104 	 * can just check for the routers at both ends of the tunnels
105 	 * and if they are the same we have a match.
106 	 */
107 	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
108 		if (!tb_tunnel_is_dp(tunnel))
109 			continue;
110 
111 		if (tunnel->src_port->sw == in->sw &&
112 		    tunnel->dst_port->sw == out->sw) {
113 			group = tunnel->src_port->group;
114 			if (group) {
115 				tb_bandwidth_group_attach_port(group, in);
116 				return group;
117 			}
118 		}
119 	}
120 
121 	/* Pick up next available group then */
122 	group = tb_find_free_bandwidth_group(tcm);
123 	if (group)
124 		tb_bandwidth_group_attach_port(group, in);
125 	else
126 		tb_port_warn(in, "no available bandwidth groups\n");
127 
128 	return group;
129 }
130 
tb_discover_bandwidth_group(struct tb_cm * tcm,struct tb_port * in,struct tb_port * out)131 static void tb_discover_bandwidth_group(struct tb_cm *tcm, struct tb_port *in,
132 					struct tb_port *out)
133 {
134 	if (usb4_dp_port_bandwidth_mode_enabled(in)) {
135 		int index, i;
136 
137 		index = usb4_dp_port_group_id(in);
138 		for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
139 			if (tcm->groups[i].index == index) {
140 				tb_bandwidth_group_attach_port(&tcm->groups[i], in);
141 				return;
142 			}
143 		}
144 	}
145 
146 	tb_attach_bandwidth_group(tcm, in, out);
147 }
148 
tb_detach_bandwidth_group(struct tb_port * in)149 static void tb_detach_bandwidth_group(struct tb_port *in)
150 {
151 	struct tb_bandwidth_group *group = in->group;
152 
153 	if (group) {
154 		in->group = NULL;
155 		list_del_init(&in->group_list);
156 
157 		tb_port_dbg(in, "detached from bandwidth group %d\n", group->index);
158 	}
159 }
160 
161 static void tb_handle_hotplug(struct work_struct *work);
162 
tb_queue_hotplug(struct tb * tb,u64 route,u8 port,bool unplug)163 static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug)
164 {
165 	struct tb_hotplug_event *ev;
166 
167 	ev = kmalloc(sizeof(*ev), GFP_KERNEL);
168 	if (!ev)
169 		return;
170 
171 	ev->tb = tb;
172 	ev->route = route;
173 	ev->port = port;
174 	ev->unplug = unplug;
175 	INIT_WORK(&ev->work, tb_handle_hotplug);
176 	queue_work(tb->wq, &ev->work);
177 }
178 
179 /* enumeration & hot plug handling */
180 
tb_add_dp_resources(struct tb_switch * sw)181 static void tb_add_dp_resources(struct tb_switch *sw)
182 {
183 	struct tb_cm *tcm = tb_priv(sw->tb);
184 	struct tb_port *port;
185 
186 	tb_switch_for_each_port(sw, port) {
187 		if (!tb_port_is_dpin(port))
188 			continue;
189 
190 		if (!tb_switch_query_dp_resource(sw, port))
191 			continue;
192 
193 		list_add_tail(&port->list, &tcm->dp_resources);
194 		tb_port_dbg(port, "DP IN resource available\n");
195 	}
196 }
197 
tb_remove_dp_resources(struct tb_switch * sw)198 static void tb_remove_dp_resources(struct tb_switch *sw)
199 {
200 	struct tb_cm *tcm = tb_priv(sw->tb);
201 	struct tb_port *port, *tmp;
202 
203 	/* Clear children resources first */
204 	tb_switch_for_each_port(sw, port) {
205 		if (tb_port_has_remote(port))
206 			tb_remove_dp_resources(port->remote->sw);
207 	}
208 
209 	list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) {
210 		if (port->sw == sw) {
211 			tb_port_dbg(port, "DP OUT resource unavailable\n");
212 			list_del_init(&port->list);
213 		}
214 	}
215 }
216 
tb_discover_dp_resource(struct tb * tb,struct tb_port * port)217 static void tb_discover_dp_resource(struct tb *tb, struct tb_port *port)
218 {
219 	struct tb_cm *tcm = tb_priv(tb);
220 	struct tb_port *p;
221 
222 	list_for_each_entry(p, &tcm->dp_resources, list) {
223 		if (p == port)
224 			return;
225 	}
226 
227 	tb_port_dbg(port, "DP %s resource available discovered\n",
228 		    tb_port_is_dpin(port) ? "IN" : "OUT");
229 	list_add_tail(&port->list, &tcm->dp_resources);
230 }
231 
tb_discover_dp_resources(struct tb * tb)232 static void tb_discover_dp_resources(struct tb *tb)
233 {
234 	struct tb_cm *tcm = tb_priv(tb);
235 	struct tb_tunnel *tunnel;
236 
237 	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
238 		if (tb_tunnel_is_dp(tunnel))
239 			tb_discover_dp_resource(tb, tunnel->dst_port);
240 	}
241 }
242 
243 /* Enables CL states up to host router */
tb_enable_clx(struct tb_switch * sw)244 static int tb_enable_clx(struct tb_switch *sw)
245 {
246 	struct tb_cm *tcm = tb_priv(sw->tb);
247 	unsigned int clx = TB_CL0S | TB_CL1;
248 	const struct tb_tunnel *tunnel;
249 	int ret;
250 
251 	/*
252 	 * Currently only enable CLx for the first link. This is enough
253 	 * to allow the CPU to save energy at least on Intel hardware
254 	 * and makes it slightly simpler to implement. We may change
255 	 * this in the future to cover the whole topology if it turns
256 	 * out to be beneficial.
257 	 */
258 	while (sw && sw->config.depth > 1)
259 		sw = tb_switch_parent(sw);
260 
261 	if (!sw)
262 		return 0;
263 
264 	if (sw->config.depth != 1)
265 		return 0;
266 
267 	/*
268 	 * If we are re-enabling then check if there is an active DMA
269 	 * tunnel and in that case bail out.
270 	 */
271 	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
272 		if (tb_tunnel_is_dma(tunnel)) {
273 			if (tb_tunnel_port_on_path(tunnel, tb_upstream_port(sw)))
274 				return 0;
275 		}
276 	}
277 
278 	/*
279 	 * Initially try with CL2. If that's not supported by the
280 	 * topology try with CL0s and CL1 and then give up.
281 	 */
282 	ret = tb_switch_clx_enable(sw, clx | TB_CL2);
283 	if (ret == -EOPNOTSUPP)
284 		ret = tb_switch_clx_enable(sw, clx);
285 	return ret == -EOPNOTSUPP ? 0 : ret;
286 }
287 
288 /* Disables CL states up to the host router */
tb_disable_clx(struct tb_switch * sw)289 static void tb_disable_clx(struct tb_switch *sw)
290 {
291 	do {
292 		if (tb_switch_clx_disable(sw) < 0)
293 			tb_sw_warn(sw, "failed to disable CL states\n");
294 		sw = tb_switch_parent(sw);
295 	} while (sw);
296 }
297 
tb_increase_switch_tmu_accuracy(struct device * dev,void * data)298 static int tb_increase_switch_tmu_accuracy(struct device *dev, void *data)
299 {
300 	struct tb_switch *sw;
301 
302 	sw = tb_to_switch(dev);
303 	if (!sw)
304 		return 0;
305 
306 	if (tb_switch_tmu_is_configured(sw, TB_SWITCH_TMU_MODE_LOWRES)) {
307 		enum tb_switch_tmu_mode mode;
308 		int ret;
309 
310 		if (tb_switch_clx_is_enabled(sw, TB_CL1))
311 			mode = TB_SWITCH_TMU_MODE_HIFI_UNI;
312 		else
313 			mode = TB_SWITCH_TMU_MODE_HIFI_BI;
314 
315 		ret = tb_switch_tmu_configure(sw, mode);
316 		if (ret)
317 			return ret;
318 
319 		return tb_switch_tmu_enable(sw);
320 	}
321 
322 	return 0;
323 }
324 
tb_increase_tmu_accuracy(struct tb_tunnel * tunnel)325 static void tb_increase_tmu_accuracy(struct tb_tunnel *tunnel)
326 {
327 	struct tb_switch *sw;
328 
329 	if (!tunnel)
330 		return;
331 
332 	/*
333 	 * Once first DP tunnel is established we change the TMU
334 	 * accuracy of first depth child routers (and the host router)
335 	 * to the highest. This is needed for the DP tunneling to work
336 	 * but also allows CL0s.
337 	 *
338 	 * If both routers are v2 then we don't need to do anything as
339 	 * they are using enhanced TMU mode that allows all CLx.
340 	 */
341 	sw = tunnel->tb->root_switch;
342 	device_for_each_child(&sw->dev, NULL, tb_increase_switch_tmu_accuracy);
343 }
344 
tb_enable_tmu(struct tb_switch * sw)345 static int tb_enable_tmu(struct tb_switch *sw)
346 {
347 	int ret;
348 
349 	/*
350 	 * If both routers at the end of the link are v2 we simply
351 	 * enable the enhanched uni-directional mode. That covers all
352 	 * the CL states. For v1 and before we need to use the normal
353 	 * rate to allow CL1 (when supported). Otherwise we keep the TMU
354 	 * running at the highest accuracy.
355 	 */
356 	ret = tb_switch_tmu_configure(sw,
357 			TB_SWITCH_TMU_MODE_MEDRES_ENHANCED_UNI);
358 	if (ret == -EOPNOTSUPP) {
359 		if (tb_switch_clx_is_enabled(sw, TB_CL1))
360 			ret = tb_switch_tmu_configure(sw,
361 					TB_SWITCH_TMU_MODE_LOWRES);
362 		else
363 			ret = tb_switch_tmu_configure(sw,
364 					TB_SWITCH_TMU_MODE_HIFI_BI);
365 	}
366 	if (ret)
367 		return ret;
368 
369 	/* If it is already enabled in correct mode, don't touch it */
370 	if (tb_switch_tmu_is_enabled(sw))
371 		return 0;
372 
373 	ret = tb_switch_tmu_disable(sw);
374 	if (ret)
375 		return ret;
376 
377 	ret = tb_switch_tmu_post_time(sw);
378 	if (ret)
379 		return ret;
380 
381 	return tb_switch_tmu_enable(sw);
382 }
383 
tb_switch_discover_tunnels(struct tb_switch * sw,struct list_head * list,bool alloc_hopids)384 static void tb_switch_discover_tunnels(struct tb_switch *sw,
385 				       struct list_head *list,
386 				       bool alloc_hopids)
387 {
388 	struct tb *tb = sw->tb;
389 	struct tb_port *port;
390 
391 	tb_switch_for_each_port(sw, port) {
392 		struct tb_tunnel *tunnel = NULL;
393 
394 		switch (port->config.type) {
395 		case TB_TYPE_DP_HDMI_IN:
396 			tunnel = tb_tunnel_discover_dp(tb, port, alloc_hopids);
397 			tb_increase_tmu_accuracy(tunnel);
398 			break;
399 
400 		case TB_TYPE_PCIE_DOWN:
401 			tunnel = tb_tunnel_discover_pci(tb, port, alloc_hopids);
402 			break;
403 
404 		case TB_TYPE_USB3_DOWN:
405 			tunnel = tb_tunnel_discover_usb3(tb, port, alloc_hopids);
406 			break;
407 
408 		default:
409 			break;
410 		}
411 
412 		if (tunnel)
413 			list_add_tail(&tunnel->list, list);
414 	}
415 
416 	tb_switch_for_each_port(sw, port) {
417 		if (tb_port_has_remote(port)) {
418 			tb_switch_discover_tunnels(port->remote->sw, list,
419 						   alloc_hopids);
420 		}
421 	}
422 }
423 
tb_discover_tunnels(struct tb * tb)424 static void tb_discover_tunnels(struct tb *tb)
425 {
426 	struct tb_cm *tcm = tb_priv(tb);
427 	struct tb_tunnel *tunnel;
428 
429 	tb_switch_discover_tunnels(tb->root_switch, &tcm->tunnel_list, true);
430 
431 	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
432 		if (tb_tunnel_is_pci(tunnel)) {
433 			struct tb_switch *parent = tunnel->dst_port->sw;
434 
435 			while (parent != tunnel->src_port->sw) {
436 				parent->boot = true;
437 				parent = tb_switch_parent(parent);
438 			}
439 		} else if (tb_tunnel_is_dp(tunnel)) {
440 			struct tb_port *in = tunnel->src_port;
441 			struct tb_port *out = tunnel->dst_port;
442 
443 			/* Keep the domain from powering down */
444 			pm_runtime_get_sync(&in->sw->dev);
445 			pm_runtime_get_sync(&out->sw->dev);
446 
447 			tb_discover_bandwidth_group(tcm, in, out);
448 		}
449 	}
450 }
451 
tb_port_configure_xdomain(struct tb_port * port,struct tb_xdomain * xd)452 static int tb_port_configure_xdomain(struct tb_port *port, struct tb_xdomain *xd)
453 {
454 	if (tb_switch_is_usb4(port->sw))
455 		return usb4_port_configure_xdomain(port, xd);
456 	return tb_lc_configure_xdomain(port);
457 }
458 
tb_port_unconfigure_xdomain(struct tb_port * port)459 static void tb_port_unconfigure_xdomain(struct tb_port *port)
460 {
461 	if (tb_switch_is_usb4(port->sw))
462 		usb4_port_unconfigure_xdomain(port);
463 	else
464 		tb_lc_unconfigure_xdomain(port);
465 
466 	tb_port_enable(port->dual_link_port);
467 }
468 
tb_scan_xdomain(struct tb_port * port)469 static void tb_scan_xdomain(struct tb_port *port)
470 {
471 	struct tb_switch *sw = port->sw;
472 	struct tb *tb = sw->tb;
473 	struct tb_xdomain *xd;
474 	u64 route;
475 
476 	if (!tb_is_xdomain_enabled())
477 		return;
478 
479 	route = tb_downstream_route(port);
480 	xd = tb_xdomain_find_by_route(tb, route);
481 	if (xd) {
482 		tb_xdomain_put(xd);
483 		return;
484 	}
485 
486 	xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid,
487 			      NULL);
488 	if (xd) {
489 		tb_port_at(route, sw)->xdomain = xd;
490 		tb_port_configure_xdomain(port, xd);
491 		tb_xdomain_add(xd);
492 	}
493 }
494 
495 /**
496  * tb_find_unused_port() - return the first inactive port on @sw
497  * @sw: Switch to find the port on
498  * @type: Port type to look for
499  */
tb_find_unused_port(struct tb_switch * sw,enum tb_port_type type)500 static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
501 					   enum tb_port_type type)
502 {
503 	struct tb_port *port;
504 
505 	tb_switch_for_each_port(sw, port) {
506 		if (tb_is_upstream_port(port))
507 			continue;
508 		if (port->config.type != type)
509 			continue;
510 		if (!port->cap_adap)
511 			continue;
512 		if (tb_port_is_enabled(port))
513 			continue;
514 		return port;
515 	}
516 	return NULL;
517 }
518 
tb_find_usb3_down(struct tb_switch * sw,const struct tb_port * port)519 static struct tb_port *tb_find_usb3_down(struct tb_switch *sw,
520 					 const struct tb_port *port)
521 {
522 	struct tb_port *down;
523 
524 	down = usb4_switch_map_usb3_down(sw, port);
525 	if (down && !tb_usb3_port_is_enabled(down))
526 		return down;
527 	return NULL;
528 }
529 
tb_find_tunnel(struct tb * tb,enum tb_tunnel_type type,struct tb_port * src_port,struct tb_port * dst_port)530 static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type,
531 					struct tb_port *src_port,
532 					struct tb_port *dst_port)
533 {
534 	struct tb_cm *tcm = tb_priv(tb);
535 	struct tb_tunnel *tunnel;
536 
537 	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
538 		if (tunnel->type == type &&
539 		    ((src_port && src_port == tunnel->src_port) ||
540 		     (dst_port && dst_port == tunnel->dst_port))) {
541 			return tunnel;
542 		}
543 	}
544 
545 	return NULL;
546 }
547 
tb_find_first_usb3_tunnel(struct tb * tb,struct tb_port * src_port,struct tb_port * dst_port)548 static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb,
549 						   struct tb_port *src_port,
550 						   struct tb_port *dst_port)
551 {
552 	struct tb_port *port, *usb3_down;
553 	struct tb_switch *sw;
554 
555 	/* Pick the router that is deepest in the topology */
556 	if (dst_port->sw->config.depth > src_port->sw->config.depth)
557 		sw = dst_port->sw;
558 	else
559 		sw = src_port->sw;
560 
561 	/* Can't be the host router */
562 	if (sw == tb->root_switch)
563 		return NULL;
564 
565 	/* Find the downstream USB4 port that leads to this router */
566 	port = tb_port_at(tb_route(sw), tb->root_switch);
567 	/* Find the corresponding host router USB3 downstream port */
568 	usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port);
569 	if (!usb3_down)
570 		return NULL;
571 
572 	return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL);
573 }
574 
tb_available_bandwidth(struct tb * tb,struct tb_port * src_port,struct tb_port * dst_port,int * available_up,int * available_down)575 static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port,
576 	struct tb_port *dst_port, int *available_up, int *available_down)
577 {
578 	int usb3_consumed_up, usb3_consumed_down, ret;
579 	struct tb_cm *tcm = tb_priv(tb);
580 	struct tb_tunnel *tunnel;
581 	struct tb_port *port;
582 
583 	tb_dbg(tb, "calculating available bandwidth between %llx:%u <-> %llx:%u\n",
584 	       tb_route(src_port->sw), src_port->port, tb_route(dst_port->sw),
585 	       dst_port->port);
586 
587 	tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
588 	if (tunnel && tunnel->src_port != src_port &&
589 	    tunnel->dst_port != dst_port) {
590 		ret = tb_tunnel_consumed_bandwidth(tunnel, &usb3_consumed_up,
591 						   &usb3_consumed_down);
592 		if (ret)
593 			return ret;
594 	} else {
595 		usb3_consumed_up = 0;
596 		usb3_consumed_down = 0;
597 	}
598 
599 	/* Maximum possible bandwidth asymmetric Gen 4 link is 120 Gb/s */
600 	*available_up = *available_down = 120000;
601 
602 	/* Find the minimum available bandwidth over all links */
603 	tb_for_each_port_on_path(src_port, dst_port, port) {
604 		int link_speed, link_width, up_bw, down_bw;
605 
606 		if (!tb_port_is_null(port))
607 			continue;
608 
609 		if (tb_is_upstream_port(port)) {
610 			link_speed = port->sw->link_speed;
611 			/*
612 			 * sw->link_width is from upstream perspective
613 			 * so we use the opposite for downstream of the
614 			 * host router.
615 			 */
616 			if (port->sw->link_width == TB_LINK_WIDTH_ASYM_TX) {
617 				up_bw = link_speed * 3 * 1000;
618 				down_bw = link_speed * 1 * 1000;
619 			} else if (port->sw->link_width == TB_LINK_WIDTH_ASYM_RX) {
620 				up_bw = link_speed * 1 * 1000;
621 				down_bw = link_speed * 3 * 1000;
622 			} else {
623 				up_bw = link_speed * port->sw->link_width * 1000;
624 				down_bw = up_bw;
625 			}
626 		} else {
627 			link_speed = tb_port_get_link_speed(port);
628 			if (link_speed < 0)
629 				return link_speed;
630 
631 			link_width = tb_port_get_link_width(port);
632 			if (link_width < 0)
633 				return link_width;
634 
635 			if (link_width == TB_LINK_WIDTH_ASYM_TX) {
636 				up_bw = link_speed * 1 * 1000;
637 				down_bw = link_speed * 3 * 1000;
638 			} else if (link_width == TB_LINK_WIDTH_ASYM_RX) {
639 				up_bw = link_speed * 3 * 1000;
640 				down_bw = link_speed * 1 * 1000;
641 			} else {
642 				up_bw = link_speed * link_width * 1000;
643 				down_bw = up_bw;
644 			}
645 		}
646 
647 		/* Leave 10% guard band */
648 		up_bw -= up_bw / 10;
649 		down_bw -= down_bw / 10;
650 
651 		tb_port_dbg(port, "link total bandwidth %d/%d Mb/s\n", up_bw,
652 			    down_bw);
653 
654 		/*
655 		 * Find all DP tunnels that cross the port and reduce
656 		 * their consumed bandwidth from the available.
657 		 */
658 		list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
659 			int dp_consumed_up, dp_consumed_down;
660 
661 			if (tb_tunnel_is_invalid(tunnel))
662 				continue;
663 
664 			if (!tb_tunnel_is_dp(tunnel))
665 				continue;
666 
667 			if (!tb_tunnel_port_on_path(tunnel, port))
668 				continue;
669 
670 			/*
671 			 * Ignore the DP tunnel between src_port and
672 			 * dst_port because it is the same tunnel and we
673 			 * may be re-calculating estimated bandwidth.
674 			 */
675 			if (tunnel->src_port == src_port &&
676 			    tunnel->dst_port == dst_port)
677 				continue;
678 
679 			ret = tb_tunnel_consumed_bandwidth(tunnel,
680 							   &dp_consumed_up,
681 							   &dp_consumed_down);
682 			if (ret)
683 				return ret;
684 
685 			up_bw -= dp_consumed_up;
686 			down_bw -= dp_consumed_down;
687 		}
688 
689 		/*
690 		 * If USB3 is tunneled from the host router down to the
691 		 * branch leading to port we need to take USB3 consumed
692 		 * bandwidth into account regardless whether it actually
693 		 * crosses the port.
694 		 */
695 		up_bw -= usb3_consumed_up;
696 		down_bw -= usb3_consumed_down;
697 
698 		if (up_bw < *available_up)
699 			*available_up = up_bw;
700 		if (down_bw < *available_down)
701 			*available_down = down_bw;
702 	}
703 
704 	if (*available_up < 0)
705 		*available_up = 0;
706 	if (*available_down < 0)
707 		*available_down = 0;
708 
709 	return 0;
710 }
711 
tb_release_unused_usb3_bandwidth(struct tb * tb,struct tb_port * src_port,struct tb_port * dst_port)712 static int tb_release_unused_usb3_bandwidth(struct tb *tb,
713 					    struct tb_port *src_port,
714 					    struct tb_port *dst_port)
715 {
716 	struct tb_tunnel *tunnel;
717 
718 	tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
719 	return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0;
720 }
721 
tb_reclaim_usb3_bandwidth(struct tb * tb,struct tb_port * src_port,struct tb_port * dst_port)722 static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port,
723 				      struct tb_port *dst_port)
724 {
725 	int ret, available_up, available_down;
726 	struct tb_tunnel *tunnel;
727 
728 	tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
729 	if (!tunnel)
730 		return;
731 
732 	tb_dbg(tb, "reclaiming unused bandwidth for USB3\n");
733 
734 	/*
735 	 * Calculate available bandwidth for the first hop USB3 tunnel.
736 	 * That determines the whole USB3 bandwidth for this branch.
737 	 */
738 	ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port,
739 				     &available_up, &available_down);
740 	if (ret) {
741 		tb_warn(tb, "failed to calculate available bandwidth\n");
742 		return;
743 	}
744 
745 	tb_dbg(tb, "available bandwidth for USB3 %d/%d Mb/s\n",
746 	       available_up, available_down);
747 
748 	tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down);
749 }
750 
tb_tunnel_usb3(struct tb * tb,struct tb_switch * sw)751 static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw)
752 {
753 	struct tb_switch *parent = tb_switch_parent(sw);
754 	int ret, available_up, available_down;
755 	struct tb_port *up, *down, *port;
756 	struct tb_cm *tcm = tb_priv(tb);
757 	struct tb_tunnel *tunnel;
758 
759 	if (!tb_acpi_may_tunnel_usb3()) {
760 		tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n");
761 		return 0;
762 	}
763 
764 	up = tb_switch_find_port(sw, TB_TYPE_USB3_UP);
765 	if (!up)
766 		return 0;
767 
768 	if (!sw->link_usb4)
769 		return 0;
770 
771 	/*
772 	 * Look up available down port. Since we are chaining it should
773 	 * be found right above this switch.
774 	 */
775 	port = tb_switch_downstream_port(sw);
776 	down = tb_find_usb3_down(parent, port);
777 	if (!down)
778 		return 0;
779 
780 	if (tb_route(parent)) {
781 		struct tb_port *parent_up;
782 		/*
783 		 * Check first that the parent switch has its upstream USB3
784 		 * port enabled. Otherwise the chain is not complete and
785 		 * there is no point setting up a new tunnel.
786 		 */
787 		parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP);
788 		if (!parent_up || !tb_port_is_enabled(parent_up))
789 			return 0;
790 
791 		/* Make all unused bandwidth available for the new tunnel */
792 		ret = tb_release_unused_usb3_bandwidth(tb, down, up);
793 		if (ret)
794 			return ret;
795 	}
796 
797 	ret = tb_available_bandwidth(tb, down, up, &available_up,
798 				     &available_down);
799 	if (ret)
800 		goto err_reclaim;
801 
802 	tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n",
803 		    available_up, available_down);
804 
805 	tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up,
806 				      available_down);
807 	if (!tunnel) {
808 		ret = -ENOMEM;
809 		goto err_reclaim;
810 	}
811 
812 	if (tb_tunnel_activate(tunnel)) {
813 		tb_port_info(up,
814 			     "USB3 tunnel activation failed, aborting\n");
815 		ret = -EIO;
816 		goto err_free;
817 	}
818 
819 	list_add_tail(&tunnel->list, &tcm->tunnel_list);
820 	if (tb_route(parent))
821 		tb_reclaim_usb3_bandwidth(tb, down, up);
822 
823 	return 0;
824 
825 err_free:
826 	tb_tunnel_free(tunnel);
827 err_reclaim:
828 	if (tb_route(parent))
829 		tb_reclaim_usb3_bandwidth(tb, down, up);
830 
831 	return ret;
832 }
833 
tb_create_usb3_tunnels(struct tb_switch * sw)834 static int tb_create_usb3_tunnels(struct tb_switch *sw)
835 {
836 	struct tb_port *port;
837 	int ret;
838 
839 	if (!tb_acpi_may_tunnel_usb3())
840 		return 0;
841 
842 	if (tb_route(sw)) {
843 		ret = tb_tunnel_usb3(sw->tb, sw);
844 		if (ret)
845 			return ret;
846 	}
847 
848 	tb_switch_for_each_port(sw, port) {
849 		if (!tb_port_has_remote(port))
850 			continue;
851 		ret = tb_create_usb3_tunnels(port->remote->sw);
852 		if (ret)
853 			return ret;
854 	}
855 
856 	return 0;
857 }
858 
859 static void tb_scan_port(struct tb_port *port);
860 
861 /*
862  * tb_scan_switch() - scan for and initialize downstream switches
863  */
tb_scan_switch(struct tb_switch * sw)864 static void tb_scan_switch(struct tb_switch *sw)
865 {
866 	struct tb_port *port;
867 
868 	pm_runtime_get_sync(&sw->dev);
869 
870 	tb_switch_for_each_port(sw, port)
871 		tb_scan_port(port);
872 
873 	pm_runtime_mark_last_busy(&sw->dev);
874 	pm_runtime_put_autosuspend(&sw->dev);
875 }
876 
877 /*
878  * tb_scan_port() - check for and initialize switches below port
879  */
tb_scan_port(struct tb_port * port)880 static void tb_scan_port(struct tb_port *port)
881 {
882 	struct tb_cm *tcm = tb_priv(port->sw->tb);
883 	struct tb_port *upstream_port;
884 	bool discovery = false;
885 	struct tb_switch *sw;
886 
887 	if (tb_is_upstream_port(port))
888 		return;
889 
890 	if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 &&
891 	    !tb_dp_port_is_enabled(port)) {
892 		tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n");
893 		tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port,
894 				 false);
895 		return;
896 	}
897 
898 	if (port->config.type != TB_TYPE_PORT)
899 		return;
900 	if (port->dual_link_port && port->link_nr)
901 		return; /*
902 			 * Downstream switch is reachable through two ports.
903 			 * Only scan on the primary port (link_nr == 0).
904 			 */
905 
906 	if (port->usb4)
907 		pm_runtime_get_sync(&port->usb4->dev);
908 
909 	if (tb_wait_for_port(port, false) <= 0)
910 		goto out_rpm_put;
911 	if (port->remote) {
912 		tb_port_dbg(port, "port already has a remote\n");
913 		goto out_rpm_put;
914 	}
915 
916 	tb_retimer_scan(port, true);
917 
918 	sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
919 			     tb_downstream_route(port));
920 	if (IS_ERR(sw)) {
921 		/*
922 		 * If there is an error accessing the connected switch
923 		 * it may be connected to another domain. Also we allow
924 		 * the other domain to be connected to a max depth switch.
925 		 */
926 		if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL)
927 			tb_scan_xdomain(port);
928 		goto out_rpm_put;
929 	}
930 
931 	if (tb_switch_configure(sw)) {
932 		tb_switch_put(sw);
933 		goto out_rpm_put;
934 	}
935 
936 	/*
937 	 * If there was previously another domain connected remove it
938 	 * first.
939 	 */
940 	if (port->xdomain) {
941 		tb_xdomain_remove(port->xdomain);
942 		tb_port_unconfigure_xdomain(port);
943 		port->xdomain = NULL;
944 	}
945 
946 	/*
947 	 * Do not send uevents until we have discovered all existing
948 	 * tunnels and know which switches were authorized already by
949 	 * the boot firmware.
950 	 */
951 	if (!tcm->hotplug_active) {
952 		dev_set_uevent_suppress(&sw->dev, true);
953 		discovery = true;
954 	}
955 
956 	/*
957 	 * At the moment Thunderbolt 2 and beyond (devices with LC) we
958 	 * can support runtime PM.
959 	 */
960 	sw->rpm = sw->generation > 1;
961 
962 	if (tb_switch_add(sw)) {
963 		tb_switch_put(sw);
964 		goto out_rpm_put;
965 	}
966 
967 	/* Link the switches using both links if available */
968 	upstream_port = tb_upstream_port(sw);
969 	port->remote = upstream_port;
970 	upstream_port->remote = port;
971 	if (port->dual_link_port && upstream_port->dual_link_port) {
972 		port->dual_link_port->remote = upstream_port->dual_link_port;
973 		upstream_port->dual_link_port->remote = port->dual_link_port;
974 	}
975 
976 	/* Enable lane bonding if supported */
977 	tb_switch_lane_bonding_enable(sw);
978 	/* Set the link configured */
979 	tb_switch_configure_link(sw);
980 	/*
981 	 * CL0s and CL1 are enabled and supported together.
982 	 * Silently ignore CLx enabling in case CLx is not supported.
983 	 */
984 	if (discovery)
985 		tb_sw_dbg(sw, "discovery, not touching CL states\n");
986 	else if (tb_enable_clx(sw))
987 		tb_sw_warn(sw, "failed to enable CL states\n");
988 
989 	if (tb_enable_tmu(sw))
990 		tb_sw_warn(sw, "failed to enable TMU\n");
991 
992 	/*
993 	 * Configuration valid needs to be set after the TMU has been
994 	 * enabled for the upstream port of the router so we do it here.
995 	 */
996 	tb_switch_configuration_valid(sw);
997 
998 	/* Scan upstream retimers */
999 	tb_retimer_scan(upstream_port, true);
1000 
1001 	/*
1002 	 * Create USB 3.x tunnels only when the switch is plugged to the
1003 	 * domain. This is because we scan the domain also during discovery
1004 	 * and want to discover existing USB 3.x tunnels before we create
1005 	 * any new.
1006 	 */
1007 	if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw))
1008 		tb_sw_warn(sw, "USB3 tunnel creation failed\n");
1009 
1010 	tb_add_dp_resources(sw);
1011 	tb_scan_switch(sw);
1012 
1013 out_rpm_put:
1014 	if (port->usb4) {
1015 		pm_runtime_mark_last_busy(&port->usb4->dev);
1016 		pm_runtime_put_autosuspend(&port->usb4->dev);
1017 	}
1018 }
1019 
tb_deactivate_and_free_tunnel(struct tb_tunnel * tunnel)1020 static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel)
1021 {
1022 	struct tb_port *src_port, *dst_port;
1023 	struct tb *tb;
1024 
1025 	if (!tunnel)
1026 		return;
1027 
1028 	tb_tunnel_deactivate(tunnel);
1029 	list_del(&tunnel->list);
1030 
1031 	tb = tunnel->tb;
1032 	src_port = tunnel->src_port;
1033 	dst_port = tunnel->dst_port;
1034 
1035 	switch (tunnel->type) {
1036 	case TB_TUNNEL_DP:
1037 		tb_detach_bandwidth_group(src_port);
1038 		/*
1039 		 * In case of DP tunnel make sure the DP IN resource is
1040 		 * deallocated properly.
1041 		 */
1042 		tb_switch_dealloc_dp_resource(src_port->sw, src_port);
1043 		/* Now we can allow the domain to runtime suspend again */
1044 		pm_runtime_mark_last_busy(&dst_port->sw->dev);
1045 		pm_runtime_put_autosuspend(&dst_port->sw->dev);
1046 		pm_runtime_mark_last_busy(&src_port->sw->dev);
1047 		pm_runtime_put_autosuspend(&src_port->sw->dev);
1048 		fallthrough;
1049 
1050 	case TB_TUNNEL_USB3:
1051 		tb_reclaim_usb3_bandwidth(tb, src_port, dst_port);
1052 		break;
1053 
1054 	default:
1055 		/*
1056 		 * PCIe and DMA tunnels do not consume guaranteed
1057 		 * bandwidth.
1058 		 */
1059 		break;
1060 	}
1061 
1062 	tb_tunnel_free(tunnel);
1063 }
1064 
1065 /*
1066  * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
1067  */
tb_free_invalid_tunnels(struct tb * tb)1068 static void tb_free_invalid_tunnels(struct tb *tb)
1069 {
1070 	struct tb_cm *tcm = tb_priv(tb);
1071 	struct tb_tunnel *tunnel;
1072 	struct tb_tunnel *n;
1073 
1074 	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1075 		if (tb_tunnel_is_invalid(tunnel))
1076 			tb_deactivate_and_free_tunnel(tunnel);
1077 	}
1078 }
1079 
1080 /*
1081  * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
1082  */
tb_free_unplugged_children(struct tb_switch * sw)1083 static void tb_free_unplugged_children(struct tb_switch *sw)
1084 {
1085 	struct tb_port *port;
1086 
1087 	tb_switch_for_each_port(sw, port) {
1088 		if (!tb_port_has_remote(port))
1089 			continue;
1090 
1091 		if (port->remote->sw->is_unplugged) {
1092 			tb_retimer_remove_all(port);
1093 			tb_remove_dp_resources(port->remote->sw);
1094 			tb_switch_unconfigure_link(port->remote->sw);
1095 			tb_switch_lane_bonding_disable(port->remote->sw);
1096 			tb_switch_remove(port->remote->sw);
1097 			port->remote = NULL;
1098 			if (port->dual_link_port)
1099 				port->dual_link_port->remote = NULL;
1100 		} else {
1101 			tb_free_unplugged_children(port->remote->sw);
1102 		}
1103 	}
1104 }
1105 
tb_find_pcie_down(struct tb_switch * sw,const struct tb_port * port)1106 static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
1107 					 const struct tb_port *port)
1108 {
1109 	struct tb_port *down = NULL;
1110 
1111 	/*
1112 	 * To keep plugging devices consistently in the same PCIe
1113 	 * hierarchy, do mapping here for switch downstream PCIe ports.
1114 	 */
1115 	if (tb_switch_is_usb4(sw)) {
1116 		down = usb4_switch_map_pcie_down(sw, port);
1117 	} else if (!tb_route(sw)) {
1118 		int phy_port = tb_phy_port_from_link(port->port);
1119 		int index;
1120 
1121 		/*
1122 		 * Hard-coded Thunderbolt port to PCIe down port mapping
1123 		 * per controller.
1124 		 */
1125 		if (tb_switch_is_cactus_ridge(sw) ||
1126 		    tb_switch_is_alpine_ridge(sw))
1127 			index = !phy_port ? 6 : 7;
1128 		else if (tb_switch_is_falcon_ridge(sw))
1129 			index = !phy_port ? 6 : 8;
1130 		else if (tb_switch_is_titan_ridge(sw))
1131 			index = !phy_port ? 8 : 9;
1132 		else
1133 			goto out;
1134 
1135 		/* Validate the hard-coding */
1136 		if (WARN_ON(index > sw->config.max_port_number))
1137 			goto out;
1138 
1139 		down = &sw->ports[index];
1140 	}
1141 
1142 	if (down) {
1143 		if (WARN_ON(!tb_port_is_pcie_down(down)))
1144 			goto out;
1145 		if (tb_pci_port_is_enabled(down))
1146 			goto out;
1147 
1148 		return down;
1149 	}
1150 
1151 out:
1152 	return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN);
1153 }
1154 
1155 static void
tb_recalc_estimated_bandwidth_for_group(struct tb_bandwidth_group * group)1156 tb_recalc_estimated_bandwidth_for_group(struct tb_bandwidth_group *group)
1157 {
1158 	struct tb_tunnel *first_tunnel;
1159 	struct tb *tb = group->tb;
1160 	struct tb_port *in;
1161 	int ret;
1162 
1163 	tb_dbg(tb, "re-calculating bandwidth estimation for group %u\n",
1164 	       group->index);
1165 
1166 	first_tunnel = NULL;
1167 	list_for_each_entry(in, &group->ports, group_list) {
1168 		int estimated_bw, estimated_up, estimated_down;
1169 		struct tb_tunnel *tunnel;
1170 		struct tb_port *out;
1171 
1172 		if (!usb4_dp_port_bandwidth_mode_enabled(in))
1173 			continue;
1174 
1175 		tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, NULL);
1176 		if (WARN_ON(!tunnel))
1177 			break;
1178 
1179 		if (!first_tunnel) {
1180 			/*
1181 			 * Since USB3 bandwidth is shared by all DP
1182 			 * tunnels under the host router USB4 port, even
1183 			 * if they do not begin from the host router, we
1184 			 * can release USB3 bandwidth just once and not
1185 			 * for each tunnel separately.
1186 			 */
1187 			first_tunnel = tunnel;
1188 			ret = tb_release_unused_usb3_bandwidth(tb,
1189 				first_tunnel->src_port, first_tunnel->dst_port);
1190 			if (ret) {
1191 				tb_port_warn(in,
1192 					"failed to release unused bandwidth\n");
1193 				break;
1194 			}
1195 		}
1196 
1197 		out = tunnel->dst_port;
1198 		ret = tb_available_bandwidth(tb, in, out, &estimated_up,
1199 					     &estimated_down);
1200 		if (ret) {
1201 			tb_port_warn(in,
1202 				"failed to re-calculate estimated bandwidth\n");
1203 			break;
1204 		}
1205 
1206 		/*
1207 		 * Estimated bandwidth includes:
1208 		 *  - already allocated bandwidth for the DP tunnel
1209 		 *  - available bandwidth along the path
1210 		 *  - bandwidth allocated for USB 3.x but not used.
1211 		 */
1212 		tb_port_dbg(in, "re-calculated estimated bandwidth %u/%u Mb/s\n",
1213 			    estimated_up, estimated_down);
1214 
1215 		if (in->sw->config.depth < out->sw->config.depth)
1216 			estimated_bw = estimated_down;
1217 		else
1218 			estimated_bw = estimated_up;
1219 
1220 		if (usb4_dp_port_set_estimated_bandwidth(in, estimated_bw))
1221 			tb_port_warn(in, "failed to update estimated bandwidth\n");
1222 	}
1223 
1224 	if (first_tunnel)
1225 		tb_reclaim_usb3_bandwidth(tb, first_tunnel->src_port,
1226 					  first_tunnel->dst_port);
1227 
1228 	tb_dbg(tb, "bandwidth estimation for group %u done\n", group->index);
1229 }
1230 
tb_recalc_estimated_bandwidth(struct tb * tb)1231 static void tb_recalc_estimated_bandwidth(struct tb *tb)
1232 {
1233 	struct tb_cm *tcm = tb_priv(tb);
1234 	int i;
1235 
1236 	tb_dbg(tb, "bandwidth consumption changed, re-calculating estimated bandwidth\n");
1237 
1238 	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
1239 		struct tb_bandwidth_group *group = &tcm->groups[i];
1240 
1241 		if (!list_empty(&group->ports))
1242 			tb_recalc_estimated_bandwidth_for_group(group);
1243 	}
1244 
1245 	tb_dbg(tb, "bandwidth re-calculation done\n");
1246 }
1247 
tb_find_dp_out(struct tb * tb,struct tb_port * in)1248 static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
1249 {
1250 	struct tb_port *host_port, *port;
1251 	struct tb_cm *tcm = tb_priv(tb);
1252 
1253 	host_port = tb_route(in->sw) ?
1254 		tb_port_at(tb_route(in->sw), tb->root_switch) : NULL;
1255 
1256 	list_for_each_entry(port, &tcm->dp_resources, list) {
1257 		if (!tb_port_is_dpout(port))
1258 			continue;
1259 
1260 		if (tb_port_is_enabled(port)) {
1261 			tb_port_dbg(port, "DP OUT in use\n");
1262 			continue;
1263 		}
1264 
1265 		tb_port_dbg(port, "DP OUT available\n");
1266 
1267 		/*
1268 		 * Keep the DP tunnel under the topology starting from
1269 		 * the same host router downstream port.
1270 		 */
1271 		if (host_port && tb_route(port->sw)) {
1272 			struct tb_port *p;
1273 
1274 			p = tb_port_at(tb_route(port->sw), tb->root_switch);
1275 			if (p != host_port)
1276 				continue;
1277 		}
1278 
1279 		return port;
1280 	}
1281 
1282 	return NULL;
1283 }
1284 
tb_tunnel_dp(struct tb * tb)1285 static void tb_tunnel_dp(struct tb *tb)
1286 {
1287 	int available_up, available_down, ret, link_nr;
1288 	struct tb_cm *tcm = tb_priv(tb);
1289 	struct tb_port *port, *in, *out;
1290 	struct tb_tunnel *tunnel;
1291 
1292 	if (!tb_acpi_may_tunnel_dp()) {
1293 		tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
1294 		return;
1295 	}
1296 
1297 	/*
1298 	 * Find pair of inactive DP IN and DP OUT adapters and then
1299 	 * establish a DP tunnel between them.
1300 	 */
1301 	tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n");
1302 
1303 	in = NULL;
1304 	out = NULL;
1305 	list_for_each_entry(port, &tcm->dp_resources, list) {
1306 		if (!tb_port_is_dpin(port))
1307 			continue;
1308 
1309 		if (tb_port_is_enabled(port)) {
1310 			tb_port_dbg(port, "DP IN in use\n");
1311 			continue;
1312 		}
1313 
1314 		tb_port_dbg(port, "DP IN available\n");
1315 
1316 		out = tb_find_dp_out(tb, port);
1317 		if (out) {
1318 			in = port;
1319 			break;
1320 		}
1321 	}
1322 
1323 	if (!in) {
1324 		tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
1325 		return;
1326 	}
1327 	if (!out) {
1328 		tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n");
1329 		return;
1330 	}
1331 
1332 	/*
1333 	 * This is only applicable to links that are not bonded (so
1334 	 * when Thunderbolt 1 hardware is involved somewhere in the
1335 	 * topology). For these try to share the DP bandwidth between
1336 	 * the two lanes.
1337 	 */
1338 	link_nr = 1;
1339 	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
1340 		if (tb_tunnel_is_dp(tunnel)) {
1341 			link_nr = 0;
1342 			break;
1343 		}
1344 	}
1345 
1346 	/*
1347 	 * DP stream needs the domain to be active so runtime resume
1348 	 * both ends of the tunnel.
1349 	 *
1350 	 * This should bring the routers in the middle active as well
1351 	 * and keeps the domain from runtime suspending while the DP
1352 	 * tunnel is active.
1353 	 */
1354 	pm_runtime_get_sync(&in->sw->dev);
1355 	pm_runtime_get_sync(&out->sw->dev);
1356 
1357 	if (tb_switch_alloc_dp_resource(in->sw, in)) {
1358 		tb_port_dbg(in, "no resource available for DP IN, not tunneling\n");
1359 		goto err_rpm_put;
1360 	}
1361 
1362 	if (!tb_attach_bandwidth_group(tcm, in, out))
1363 		goto err_dealloc_dp;
1364 
1365 	/* Make all unused USB3 bandwidth available for the new DP tunnel */
1366 	ret = tb_release_unused_usb3_bandwidth(tb, in, out);
1367 	if (ret) {
1368 		tb_warn(tb, "failed to release unused bandwidth\n");
1369 		goto err_detach_group;
1370 	}
1371 
1372 	ret = tb_available_bandwidth(tb, in, out, &available_up, &available_down);
1373 	if (ret)
1374 		goto err_reclaim_usb;
1375 
1376 	tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
1377 	       available_up, available_down);
1378 
1379 	tunnel = tb_tunnel_alloc_dp(tb, in, out, link_nr, available_up,
1380 				    available_down);
1381 	if (!tunnel) {
1382 		tb_port_dbg(out, "could not allocate DP tunnel\n");
1383 		goto err_reclaim_usb;
1384 	}
1385 
1386 	if (tb_tunnel_activate(tunnel)) {
1387 		tb_port_info(out, "DP tunnel activation failed, aborting\n");
1388 		goto err_free;
1389 	}
1390 
1391 	list_add_tail(&tunnel->list, &tcm->tunnel_list);
1392 	tb_reclaim_usb3_bandwidth(tb, in, out);
1393 
1394 	/* Update the domain with the new bandwidth estimation */
1395 	tb_recalc_estimated_bandwidth(tb);
1396 
1397 	/*
1398 	 * In case of DP tunnel exists, change host router's 1st children
1399 	 * TMU mode to HiFi for CL0s to work.
1400 	 */
1401 	tb_increase_tmu_accuracy(tunnel);
1402 	return;
1403 
1404 err_free:
1405 	tb_tunnel_free(tunnel);
1406 err_reclaim_usb:
1407 	tb_reclaim_usb3_bandwidth(tb, in, out);
1408 err_detach_group:
1409 	tb_detach_bandwidth_group(in);
1410 err_dealloc_dp:
1411 	tb_switch_dealloc_dp_resource(in->sw, in);
1412 err_rpm_put:
1413 	pm_runtime_mark_last_busy(&out->sw->dev);
1414 	pm_runtime_put_autosuspend(&out->sw->dev);
1415 	pm_runtime_mark_last_busy(&in->sw->dev);
1416 	pm_runtime_put_autosuspend(&in->sw->dev);
1417 }
1418 
tb_dp_resource_unavailable(struct tb * tb,struct tb_port * port)1419 static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port)
1420 {
1421 	struct tb_port *in, *out;
1422 	struct tb_tunnel *tunnel;
1423 
1424 	if (tb_port_is_dpin(port)) {
1425 		tb_port_dbg(port, "DP IN resource unavailable\n");
1426 		in = port;
1427 		out = NULL;
1428 	} else {
1429 		tb_port_dbg(port, "DP OUT resource unavailable\n");
1430 		in = NULL;
1431 		out = port;
1432 	}
1433 
1434 	tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out);
1435 	tb_deactivate_and_free_tunnel(tunnel);
1436 	list_del_init(&port->list);
1437 
1438 	/*
1439 	 * See if there is another DP OUT port that can be used for
1440 	 * to create another tunnel.
1441 	 */
1442 	tb_recalc_estimated_bandwidth(tb);
1443 	tb_tunnel_dp(tb);
1444 }
1445 
tb_dp_resource_available(struct tb * tb,struct tb_port * port)1446 static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
1447 {
1448 	struct tb_cm *tcm = tb_priv(tb);
1449 	struct tb_port *p;
1450 
1451 	if (tb_port_is_enabled(port))
1452 		return;
1453 
1454 	list_for_each_entry(p, &tcm->dp_resources, list) {
1455 		if (p == port)
1456 			return;
1457 	}
1458 
1459 	tb_port_dbg(port, "DP %s resource available\n",
1460 		    tb_port_is_dpin(port) ? "IN" : "OUT");
1461 	list_add_tail(&port->list, &tcm->dp_resources);
1462 
1463 	/* Look for suitable DP IN <-> DP OUT pairs now */
1464 	tb_tunnel_dp(tb);
1465 }
1466 
tb_disconnect_and_release_dp(struct tb * tb)1467 static void tb_disconnect_and_release_dp(struct tb *tb)
1468 {
1469 	struct tb_cm *tcm = tb_priv(tb);
1470 	struct tb_tunnel *tunnel, *n;
1471 
1472 	/*
1473 	 * Tear down all DP tunnels and release their resources. They
1474 	 * will be re-established after resume based on plug events.
1475 	 */
1476 	list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) {
1477 		if (tb_tunnel_is_dp(tunnel))
1478 			tb_deactivate_and_free_tunnel(tunnel);
1479 	}
1480 
1481 	while (!list_empty(&tcm->dp_resources)) {
1482 		struct tb_port *port;
1483 
1484 		port = list_first_entry(&tcm->dp_resources,
1485 					struct tb_port, list);
1486 		list_del_init(&port->list);
1487 	}
1488 }
1489 
tb_disconnect_pci(struct tb * tb,struct tb_switch * sw)1490 static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw)
1491 {
1492 	struct tb_tunnel *tunnel;
1493 	struct tb_port *up;
1494 
1495 	up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1496 	if (WARN_ON(!up))
1497 		return -ENODEV;
1498 
1499 	tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up);
1500 	if (WARN_ON(!tunnel))
1501 		return -ENODEV;
1502 
1503 	tb_switch_xhci_disconnect(sw);
1504 
1505 	tb_tunnel_deactivate(tunnel);
1506 	list_del(&tunnel->list);
1507 	tb_tunnel_free(tunnel);
1508 	return 0;
1509 }
1510 
tb_tunnel_pci(struct tb * tb,struct tb_switch * sw)1511 static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
1512 {
1513 	struct tb_port *up, *down, *port;
1514 	struct tb_cm *tcm = tb_priv(tb);
1515 	struct tb_tunnel *tunnel;
1516 
1517 	up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1518 	if (!up)
1519 		return 0;
1520 
1521 	/*
1522 	 * Look up available down port. Since we are chaining it should
1523 	 * be found right above this switch.
1524 	 */
1525 	port = tb_switch_downstream_port(sw);
1526 	down = tb_find_pcie_down(tb_switch_parent(sw), port);
1527 	if (!down)
1528 		return 0;
1529 
1530 	tunnel = tb_tunnel_alloc_pci(tb, up, down);
1531 	if (!tunnel)
1532 		return -ENOMEM;
1533 
1534 	if (tb_tunnel_activate(tunnel)) {
1535 		tb_port_info(up,
1536 			     "PCIe tunnel activation failed, aborting\n");
1537 		tb_tunnel_free(tunnel);
1538 		return -EIO;
1539 	}
1540 
1541 	/*
1542 	 * PCIe L1 is needed to enable CL0s for Titan Ridge so enable it
1543 	 * here.
1544 	 */
1545 	if (tb_switch_pcie_l1_enable(sw))
1546 		tb_sw_warn(sw, "failed to enable PCIe L1 for Titan Ridge\n");
1547 
1548 	if (tb_switch_xhci_connect(sw))
1549 		tb_sw_warn(sw, "failed to connect xHCI\n");
1550 
1551 	list_add_tail(&tunnel->list, &tcm->tunnel_list);
1552 	return 0;
1553 }
1554 
tb_approve_xdomain_paths(struct tb * tb,struct tb_xdomain * xd,int transmit_path,int transmit_ring,int receive_path,int receive_ring)1555 static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1556 				    int transmit_path, int transmit_ring,
1557 				    int receive_path, int receive_ring)
1558 {
1559 	struct tb_cm *tcm = tb_priv(tb);
1560 	struct tb_port *nhi_port, *dst_port;
1561 	struct tb_tunnel *tunnel;
1562 	struct tb_switch *sw;
1563 	int ret;
1564 
1565 	sw = tb_to_switch(xd->dev.parent);
1566 	dst_port = tb_port_at(xd->route, sw);
1567 	nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1568 
1569 	mutex_lock(&tb->lock);
1570 
1571 	/*
1572 	 * When tunneling DMA paths the link should not enter CL states
1573 	 * so disable them now.
1574 	 */
1575 	tb_disable_clx(sw);
1576 
1577 	tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, transmit_path,
1578 				     transmit_ring, receive_path, receive_ring);
1579 	if (!tunnel) {
1580 		ret = -ENOMEM;
1581 		goto err_clx;
1582 	}
1583 
1584 	if (tb_tunnel_activate(tunnel)) {
1585 		tb_port_info(nhi_port,
1586 			     "DMA tunnel activation failed, aborting\n");
1587 		ret = -EIO;
1588 		goto err_free;
1589 	}
1590 
1591 	list_add_tail(&tunnel->list, &tcm->tunnel_list);
1592 	mutex_unlock(&tb->lock);
1593 	return 0;
1594 
1595 err_free:
1596 	tb_tunnel_free(tunnel);
1597 err_clx:
1598 	tb_enable_clx(sw);
1599 	mutex_unlock(&tb->lock);
1600 
1601 	return ret;
1602 }
1603 
__tb_disconnect_xdomain_paths(struct tb * tb,struct tb_xdomain * xd,int transmit_path,int transmit_ring,int receive_path,int receive_ring)1604 static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1605 					  int transmit_path, int transmit_ring,
1606 					  int receive_path, int receive_ring)
1607 {
1608 	struct tb_cm *tcm = tb_priv(tb);
1609 	struct tb_port *nhi_port, *dst_port;
1610 	struct tb_tunnel *tunnel, *n;
1611 	struct tb_switch *sw;
1612 
1613 	sw = tb_to_switch(xd->dev.parent);
1614 	dst_port = tb_port_at(xd->route, sw);
1615 	nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1616 
1617 	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1618 		if (!tb_tunnel_is_dma(tunnel))
1619 			continue;
1620 		if (tunnel->src_port != nhi_port || tunnel->dst_port != dst_port)
1621 			continue;
1622 
1623 		if (tb_tunnel_match_dma(tunnel, transmit_path, transmit_ring,
1624 					receive_path, receive_ring))
1625 			tb_deactivate_and_free_tunnel(tunnel);
1626 	}
1627 
1628 	/*
1629 	 * Try to re-enable CL states now, it is OK if this fails
1630 	 * because we may still have another DMA tunnel active through
1631 	 * the same host router USB4 downstream port.
1632 	 */
1633 	tb_enable_clx(sw);
1634 }
1635 
tb_disconnect_xdomain_paths(struct tb * tb,struct tb_xdomain * xd,int transmit_path,int transmit_ring,int receive_path,int receive_ring)1636 static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1637 				       int transmit_path, int transmit_ring,
1638 				       int receive_path, int receive_ring)
1639 {
1640 	if (!xd->is_unplugged) {
1641 		mutex_lock(&tb->lock);
1642 		__tb_disconnect_xdomain_paths(tb, xd, transmit_path,
1643 					      transmit_ring, receive_path,
1644 					      receive_ring);
1645 		mutex_unlock(&tb->lock);
1646 	}
1647 	return 0;
1648 }
1649 
1650 /* hotplug handling */
1651 
1652 /*
1653  * tb_handle_hotplug() - handle hotplug event
1654  *
1655  * Executes on tb->wq.
1656  */
tb_handle_hotplug(struct work_struct * work)1657 static void tb_handle_hotplug(struct work_struct *work)
1658 {
1659 	struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
1660 	struct tb *tb = ev->tb;
1661 	struct tb_cm *tcm = tb_priv(tb);
1662 	struct tb_switch *sw;
1663 	struct tb_port *port;
1664 
1665 	/* Bring the domain back from sleep if it was suspended */
1666 	pm_runtime_get_sync(&tb->dev);
1667 
1668 	mutex_lock(&tb->lock);
1669 	if (!tcm->hotplug_active)
1670 		goto out; /* during init, suspend or shutdown */
1671 
1672 	sw = tb_switch_find_by_route(tb, ev->route);
1673 	if (!sw) {
1674 		tb_warn(tb,
1675 			"hotplug event from non existent switch %llx:%x (unplug: %d)\n",
1676 			ev->route, ev->port, ev->unplug);
1677 		goto out;
1678 	}
1679 	if (ev->port > sw->config.max_port_number) {
1680 		tb_warn(tb,
1681 			"hotplug event from non existent port %llx:%x (unplug: %d)\n",
1682 			ev->route, ev->port, ev->unplug);
1683 		goto put_sw;
1684 	}
1685 	port = &sw->ports[ev->port];
1686 	if (tb_is_upstream_port(port)) {
1687 		tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
1688 		       ev->route, ev->port, ev->unplug);
1689 		goto put_sw;
1690 	}
1691 
1692 	pm_runtime_get_sync(&sw->dev);
1693 
1694 	if (ev->unplug) {
1695 		tb_retimer_remove_all(port);
1696 
1697 		if (tb_port_has_remote(port)) {
1698 			tb_port_dbg(port, "switch unplugged\n");
1699 			tb_sw_set_unplugged(port->remote->sw);
1700 			tb_free_invalid_tunnels(tb);
1701 			tb_remove_dp_resources(port->remote->sw);
1702 			tb_switch_tmu_disable(port->remote->sw);
1703 			tb_switch_unconfigure_link(port->remote->sw);
1704 			tb_switch_lane_bonding_disable(port->remote->sw);
1705 			tb_switch_remove(port->remote->sw);
1706 			port->remote = NULL;
1707 			if (port->dual_link_port)
1708 				port->dual_link_port->remote = NULL;
1709 			/* Maybe we can create another DP tunnel */
1710 			tb_recalc_estimated_bandwidth(tb);
1711 			tb_tunnel_dp(tb);
1712 		} else if (port->xdomain) {
1713 			struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);
1714 
1715 			tb_port_dbg(port, "xdomain unplugged\n");
1716 			/*
1717 			 * Service drivers are unbound during
1718 			 * tb_xdomain_remove() so setting XDomain as
1719 			 * unplugged here prevents deadlock if they call
1720 			 * tb_xdomain_disable_paths(). We will tear down
1721 			 * all the tunnels below.
1722 			 */
1723 			xd->is_unplugged = true;
1724 			tb_xdomain_remove(xd);
1725 			port->xdomain = NULL;
1726 			__tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1);
1727 			tb_xdomain_put(xd);
1728 			tb_port_unconfigure_xdomain(port);
1729 		} else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1730 			tb_dp_resource_unavailable(tb, port);
1731 		} else if (!port->port) {
1732 			tb_sw_dbg(sw, "xHCI disconnect request\n");
1733 			tb_switch_xhci_disconnect(sw);
1734 		} else {
1735 			tb_port_dbg(port,
1736 				   "got unplug event for disconnected port, ignoring\n");
1737 		}
1738 	} else if (port->remote) {
1739 		tb_port_dbg(port, "got plug event for connected port, ignoring\n");
1740 	} else if (!port->port && sw->authorized) {
1741 		tb_sw_dbg(sw, "xHCI connect request\n");
1742 		tb_switch_xhci_connect(sw);
1743 	} else {
1744 		if (tb_port_is_null(port)) {
1745 			tb_port_dbg(port, "hotplug: scanning\n");
1746 			tb_scan_port(port);
1747 			if (!port->remote)
1748 				tb_port_dbg(port, "hotplug: no switch found\n");
1749 		} else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1750 			tb_dp_resource_available(tb, port);
1751 		}
1752 	}
1753 
1754 	pm_runtime_mark_last_busy(&sw->dev);
1755 	pm_runtime_put_autosuspend(&sw->dev);
1756 
1757 put_sw:
1758 	tb_switch_put(sw);
1759 out:
1760 	mutex_unlock(&tb->lock);
1761 
1762 	pm_runtime_mark_last_busy(&tb->dev);
1763 	pm_runtime_put_autosuspend(&tb->dev);
1764 
1765 	kfree(ev);
1766 }
1767 
tb_alloc_dp_bandwidth(struct tb_tunnel * tunnel,int * requested_up,int * requested_down)1768 static int tb_alloc_dp_bandwidth(struct tb_tunnel *tunnel, int *requested_up,
1769 				 int *requested_down)
1770 {
1771 	int allocated_up, allocated_down, available_up, available_down, ret;
1772 	int requested_up_corrected, requested_down_corrected, granularity;
1773 	int max_up, max_down, max_up_rounded, max_down_rounded;
1774 	struct tb *tb = tunnel->tb;
1775 	struct tb_port *in, *out;
1776 
1777 	ret = tb_tunnel_allocated_bandwidth(tunnel, &allocated_up, &allocated_down);
1778 	if (ret)
1779 		return ret;
1780 
1781 	in = tunnel->src_port;
1782 	out = tunnel->dst_port;
1783 
1784 	tb_port_dbg(in, "bandwidth allocated currently %d/%d Mb/s\n",
1785 		    allocated_up, allocated_down);
1786 
1787 	/*
1788 	 * If we get rounded up request from graphics side, say HBR2 x 4
1789 	 * that is 17500 instead of 17280 (this is because of the
1790 	 * granularity), we allow it too. Here the graphics has already
1791 	 * negotiated with the DPRX the maximum possible rates (which is
1792 	 * 17280 in this case).
1793 	 *
1794 	 * Since the link cannot go higher than 17280 we use that in our
1795 	 * calculations but the DP IN adapter Allocated BW write must be
1796 	 * the same value (17500) otherwise the adapter will mark it as
1797 	 * failed for graphics.
1798 	 */
1799 	ret = tb_tunnel_maximum_bandwidth(tunnel, &max_up, &max_down);
1800 	if (ret)
1801 		return ret;
1802 
1803 	ret = usb4_dp_port_granularity(in);
1804 	if (ret < 0)
1805 		return ret;
1806 	granularity = ret;
1807 
1808 	max_up_rounded = roundup(max_up, granularity);
1809 	max_down_rounded = roundup(max_down, granularity);
1810 
1811 	/*
1812 	 * This will "fix" the request down to the maximum supported
1813 	 * rate * lanes if it is at the maximum rounded up level.
1814 	 */
1815 	requested_up_corrected = *requested_up;
1816 	if (requested_up_corrected == max_up_rounded)
1817 		requested_up_corrected = max_up;
1818 	else if (requested_up_corrected < 0)
1819 		requested_up_corrected = 0;
1820 	requested_down_corrected = *requested_down;
1821 	if (requested_down_corrected == max_down_rounded)
1822 		requested_down_corrected = max_down;
1823 	else if (requested_down_corrected < 0)
1824 		requested_down_corrected = 0;
1825 
1826 	tb_port_dbg(in, "corrected bandwidth request %d/%d Mb/s\n",
1827 		    requested_up_corrected, requested_down_corrected);
1828 
1829 	if ((*requested_up >= 0 && requested_up_corrected > max_up_rounded) ||
1830 	    (*requested_down >= 0 && requested_down_corrected > max_down_rounded)) {
1831 		tb_port_dbg(in, "bandwidth request too high (%d/%d Mb/s > %d/%d Mb/s)\n",
1832 			    requested_up_corrected, requested_down_corrected,
1833 			    max_up_rounded, max_down_rounded);
1834 		return -ENOBUFS;
1835 	}
1836 
1837 	if ((*requested_up >= 0 && requested_up_corrected <= allocated_up) ||
1838 	    (*requested_down >= 0 && requested_down_corrected <= allocated_down)) {
1839 		/*
1840 		 * If requested bandwidth is less or equal than what is
1841 		 * currently allocated to that tunnel we simply change
1842 		 * the reservation of the tunnel. Since all the tunnels
1843 		 * going out from the same USB4 port are in the same
1844 		 * group the released bandwidth will be taken into
1845 		 * account for the other tunnels automatically below.
1846 		 */
1847 		return tb_tunnel_alloc_bandwidth(tunnel, requested_up,
1848 						 requested_down);
1849 	}
1850 
1851 	/*
1852 	 * More bandwidth is requested. Release all the potential
1853 	 * bandwidth from USB3 first.
1854 	 */
1855 	ret = tb_release_unused_usb3_bandwidth(tb, in, out);
1856 	if (ret)
1857 		return ret;
1858 
1859 	/*
1860 	 * Then go over all tunnels that cross the same USB4 ports (they
1861 	 * are also in the same group but we use the same function here
1862 	 * that we use with the normal bandwidth allocation).
1863 	 */
1864 	ret = tb_available_bandwidth(tb, in, out, &available_up, &available_down);
1865 	if (ret)
1866 		goto reclaim;
1867 
1868 	tb_port_dbg(in, "bandwidth available for allocation %d/%d Mb/s\n",
1869 		    available_up, available_down);
1870 
1871 	if ((*requested_up >= 0 && available_up >= requested_up_corrected) ||
1872 	    (*requested_down >= 0 && available_down >= requested_down_corrected)) {
1873 		ret = tb_tunnel_alloc_bandwidth(tunnel, requested_up,
1874 						requested_down);
1875 	} else {
1876 		ret = -ENOBUFS;
1877 	}
1878 
1879 reclaim:
1880 	tb_reclaim_usb3_bandwidth(tb, in, out);
1881 	return ret;
1882 }
1883 
tb_handle_dp_bandwidth_request(struct work_struct * work)1884 static void tb_handle_dp_bandwidth_request(struct work_struct *work)
1885 {
1886 	struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
1887 	int requested_bw, requested_up, requested_down, ret;
1888 	struct tb_port *in, *out;
1889 	struct tb_tunnel *tunnel;
1890 	struct tb *tb = ev->tb;
1891 	struct tb_cm *tcm = tb_priv(tb);
1892 	struct tb_switch *sw;
1893 
1894 	pm_runtime_get_sync(&tb->dev);
1895 
1896 	mutex_lock(&tb->lock);
1897 	if (!tcm->hotplug_active)
1898 		goto unlock;
1899 
1900 	sw = tb_switch_find_by_route(tb, ev->route);
1901 	if (!sw) {
1902 		tb_warn(tb, "bandwidth request from non-existent router %llx\n",
1903 			ev->route);
1904 		goto unlock;
1905 	}
1906 
1907 	in = &sw->ports[ev->port];
1908 	if (!tb_port_is_dpin(in)) {
1909 		tb_port_warn(in, "bandwidth request to non-DP IN adapter\n");
1910 		goto put_sw;
1911 	}
1912 
1913 	tb_port_dbg(in, "handling bandwidth allocation request\n");
1914 
1915 	if (!usb4_dp_port_bandwidth_mode_enabled(in)) {
1916 		tb_port_warn(in, "bandwidth allocation mode not enabled\n");
1917 		goto put_sw;
1918 	}
1919 
1920 	ret = usb4_dp_port_requested_bandwidth(in);
1921 	if (ret < 0) {
1922 		if (ret == -ENODATA)
1923 			tb_port_dbg(in, "no bandwidth request active\n");
1924 		else
1925 			tb_port_warn(in, "failed to read requested bandwidth\n");
1926 		goto put_sw;
1927 	}
1928 	requested_bw = ret;
1929 
1930 	tb_port_dbg(in, "requested bandwidth %d Mb/s\n", requested_bw);
1931 
1932 	tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, NULL);
1933 	if (!tunnel) {
1934 		tb_port_warn(in, "failed to find tunnel\n");
1935 		goto put_sw;
1936 	}
1937 
1938 	out = tunnel->dst_port;
1939 
1940 	if (in->sw->config.depth < out->sw->config.depth) {
1941 		requested_up = -1;
1942 		requested_down = requested_bw;
1943 	} else {
1944 		requested_up = requested_bw;
1945 		requested_down = -1;
1946 	}
1947 
1948 	ret = tb_alloc_dp_bandwidth(tunnel, &requested_up, &requested_down);
1949 	if (ret) {
1950 		if (ret == -ENOBUFS)
1951 			tb_port_warn(in, "not enough bandwidth available\n");
1952 		else
1953 			tb_port_warn(in, "failed to change bandwidth allocation\n");
1954 	} else {
1955 		tb_port_dbg(in, "bandwidth allocation changed to %d/%d Mb/s\n",
1956 			    requested_up, requested_down);
1957 
1958 		/* Update other clients about the allocation change */
1959 		tb_recalc_estimated_bandwidth(tb);
1960 	}
1961 
1962 put_sw:
1963 	tb_switch_put(sw);
1964 unlock:
1965 	mutex_unlock(&tb->lock);
1966 
1967 	pm_runtime_mark_last_busy(&tb->dev);
1968 	pm_runtime_put_autosuspend(&tb->dev);
1969 
1970 	kfree(ev);
1971 }
1972 
tb_queue_dp_bandwidth_request(struct tb * tb,u64 route,u8 port)1973 static void tb_queue_dp_bandwidth_request(struct tb *tb, u64 route, u8 port)
1974 {
1975 	struct tb_hotplug_event *ev;
1976 
1977 	ev = kmalloc(sizeof(*ev), GFP_KERNEL);
1978 	if (!ev)
1979 		return;
1980 
1981 	ev->tb = tb;
1982 	ev->route = route;
1983 	ev->port = port;
1984 	INIT_WORK(&ev->work, tb_handle_dp_bandwidth_request);
1985 	queue_work(tb->wq, &ev->work);
1986 }
1987 
tb_handle_notification(struct tb * tb,u64 route,const struct cfg_error_pkg * error)1988 static void tb_handle_notification(struct tb *tb, u64 route,
1989 				   const struct cfg_error_pkg *error)
1990 {
1991 
1992 	switch (error->error) {
1993 	case TB_CFG_ERROR_PCIE_WAKE:
1994 	case TB_CFG_ERROR_DP_CON_CHANGE:
1995 	case TB_CFG_ERROR_DPTX_DISCOVERY:
1996 		if (tb_cfg_ack_notification(tb->ctl, route, error))
1997 			tb_warn(tb, "could not ack notification on %llx\n",
1998 				route);
1999 		break;
2000 
2001 	case TB_CFG_ERROR_DP_BW:
2002 		if (tb_cfg_ack_notification(tb->ctl, route, error))
2003 			tb_warn(tb, "could not ack notification on %llx\n",
2004 				route);
2005 		tb_queue_dp_bandwidth_request(tb, route, error->port);
2006 		break;
2007 
2008 	default:
2009 		/* Ignore for now */
2010 		break;
2011 	}
2012 }
2013 
2014 /*
2015  * tb_schedule_hotplug_handler() - callback function for the control channel
2016  *
2017  * Delegates to tb_handle_hotplug.
2018  */
tb_handle_event(struct tb * tb,enum tb_cfg_pkg_type type,const void * buf,size_t size)2019 static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
2020 			    const void *buf, size_t size)
2021 {
2022 	const struct cfg_event_pkg *pkg = buf;
2023 	u64 route = tb_cfg_get_route(&pkg->header);
2024 
2025 	switch (type) {
2026 	case TB_CFG_PKG_ERROR:
2027 		tb_handle_notification(tb, route, (const struct cfg_error_pkg *)buf);
2028 		return;
2029 	case TB_CFG_PKG_EVENT:
2030 		break;
2031 	default:
2032 		tb_warn(tb, "unexpected event %#x, ignoring\n", type);
2033 		return;
2034 	}
2035 
2036 	if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) {
2037 		tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
2038 			pkg->port);
2039 	}
2040 
2041 	tb_queue_hotplug(tb, route, pkg->port, pkg->unplug);
2042 }
2043 
tb_stop(struct tb * tb)2044 static void tb_stop(struct tb *tb)
2045 {
2046 	struct tb_cm *tcm = tb_priv(tb);
2047 	struct tb_tunnel *tunnel;
2048 	struct tb_tunnel *n;
2049 
2050 	cancel_delayed_work(&tcm->remove_work);
2051 	/* tunnels are only present after everything has been initialized */
2052 	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
2053 		/*
2054 		 * DMA tunnels require the driver to be functional so we
2055 		 * tear them down. Other protocol tunnels can be left
2056 		 * intact.
2057 		 */
2058 		if (tb_tunnel_is_dma(tunnel))
2059 			tb_tunnel_deactivate(tunnel);
2060 		tb_tunnel_free(tunnel);
2061 	}
2062 	tb_switch_remove(tb->root_switch);
2063 	tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
2064 }
2065 
tb_scan_finalize_switch(struct device * dev,void * data)2066 static int tb_scan_finalize_switch(struct device *dev, void *data)
2067 {
2068 	if (tb_is_switch(dev)) {
2069 		struct tb_switch *sw = tb_to_switch(dev);
2070 
2071 		/*
2072 		 * If we found that the switch was already setup by the
2073 		 * boot firmware, mark it as authorized now before we
2074 		 * send uevent to userspace.
2075 		 */
2076 		if (sw->boot)
2077 			sw->authorized = 1;
2078 
2079 		dev_set_uevent_suppress(dev, false);
2080 		kobject_uevent(&dev->kobj, KOBJ_ADD);
2081 		device_for_each_child(dev, NULL, tb_scan_finalize_switch);
2082 	}
2083 
2084 	return 0;
2085 }
2086 
tb_start(struct tb * tb)2087 static int tb_start(struct tb *tb)
2088 {
2089 	struct tb_cm *tcm = tb_priv(tb);
2090 	int ret;
2091 
2092 	tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
2093 	if (IS_ERR(tb->root_switch))
2094 		return PTR_ERR(tb->root_switch);
2095 
2096 	/*
2097 	 * ICM firmware upgrade needs running firmware and in native
2098 	 * mode that is not available so disable firmware upgrade of the
2099 	 * root switch.
2100 	 *
2101 	 * However, USB4 routers support NVM firmware upgrade if they
2102 	 * implement the necessary router operations.
2103 	 */
2104 	tb->root_switch->no_nvm_upgrade = !tb_switch_is_usb4(tb->root_switch);
2105 	/* All USB4 routers support runtime PM */
2106 	tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch);
2107 
2108 	ret = tb_switch_configure(tb->root_switch);
2109 	if (ret) {
2110 		tb_switch_put(tb->root_switch);
2111 		return ret;
2112 	}
2113 
2114 	/* Announce the switch to the world */
2115 	ret = tb_switch_add(tb->root_switch);
2116 	if (ret) {
2117 		tb_switch_put(tb->root_switch);
2118 		return ret;
2119 	}
2120 
2121 	/*
2122 	 * To support highest CLx state, we set host router's TMU to
2123 	 * Normal mode.
2124 	 */
2125 	tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_MODE_LOWRES);
2126 	/* Enable TMU if it is off */
2127 	tb_switch_tmu_enable(tb->root_switch);
2128 	/* Full scan to discover devices added before the driver was loaded. */
2129 	tb_scan_switch(tb->root_switch);
2130 	/* Find out tunnels created by the boot firmware */
2131 	tb_discover_tunnels(tb);
2132 	/* Add DP resources from the DP tunnels created by the boot firmware */
2133 	tb_discover_dp_resources(tb);
2134 	/*
2135 	 * If the boot firmware did not create USB 3.x tunnels create them
2136 	 * now for the whole topology.
2137 	 */
2138 	tb_create_usb3_tunnels(tb->root_switch);
2139 	/* Add DP IN resources for the root switch */
2140 	tb_add_dp_resources(tb->root_switch);
2141 	/* Make the discovered switches available to the userspace */
2142 	device_for_each_child(&tb->root_switch->dev, NULL,
2143 			      tb_scan_finalize_switch);
2144 
2145 	/* Allow tb_handle_hotplug to progress events */
2146 	tcm->hotplug_active = true;
2147 	return 0;
2148 }
2149 
tb_suspend_noirq(struct tb * tb)2150 static int tb_suspend_noirq(struct tb *tb)
2151 {
2152 	struct tb_cm *tcm = tb_priv(tb);
2153 
2154 	tb_dbg(tb, "suspending...\n");
2155 	tb_disconnect_and_release_dp(tb);
2156 	tb_switch_suspend(tb->root_switch, false);
2157 	tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
2158 	tb_dbg(tb, "suspend finished\n");
2159 
2160 	return 0;
2161 }
2162 
tb_restore_children(struct tb_switch * sw)2163 static void tb_restore_children(struct tb_switch *sw)
2164 {
2165 	struct tb_port *port;
2166 
2167 	/* No need to restore if the router is already unplugged */
2168 	if (sw->is_unplugged)
2169 		return;
2170 
2171 	if (tb_enable_clx(sw))
2172 		tb_sw_warn(sw, "failed to re-enable CL states\n");
2173 
2174 	if (tb_enable_tmu(sw))
2175 		tb_sw_warn(sw, "failed to restore TMU configuration\n");
2176 
2177 	tb_switch_configuration_valid(sw);
2178 
2179 	tb_switch_for_each_port(sw, port) {
2180 		if (!tb_port_has_remote(port) && !port->xdomain)
2181 			continue;
2182 
2183 		if (port->remote) {
2184 			tb_switch_lane_bonding_enable(port->remote->sw);
2185 			tb_switch_configure_link(port->remote->sw);
2186 
2187 			tb_restore_children(port->remote->sw);
2188 		} else if (port->xdomain) {
2189 			tb_port_configure_xdomain(port, port->xdomain);
2190 		}
2191 	}
2192 }
2193 
tb_resume_noirq(struct tb * tb)2194 static int tb_resume_noirq(struct tb *tb)
2195 {
2196 	struct tb_cm *tcm = tb_priv(tb);
2197 	struct tb_tunnel *tunnel, *n;
2198 	unsigned int usb3_delay = 0;
2199 	LIST_HEAD(tunnels);
2200 
2201 	tb_dbg(tb, "resuming...\n");
2202 
2203 	/* remove any pci devices the firmware might have setup */
2204 	tb_switch_reset(tb->root_switch);
2205 
2206 	tb_switch_resume(tb->root_switch);
2207 	tb_free_invalid_tunnels(tb);
2208 	tb_free_unplugged_children(tb->root_switch);
2209 	tb_restore_children(tb->root_switch);
2210 
2211 	/*
2212 	 * If we get here from suspend to disk the boot firmware or the
2213 	 * restore kernel might have created tunnels of its own. Since
2214 	 * we cannot be sure they are usable for us we find and tear
2215 	 * them down.
2216 	 */
2217 	tb_switch_discover_tunnels(tb->root_switch, &tunnels, false);
2218 	list_for_each_entry_safe_reverse(tunnel, n, &tunnels, list) {
2219 		if (tb_tunnel_is_usb3(tunnel))
2220 			usb3_delay = 500;
2221 		tb_tunnel_deactivate(tunnel);
2222 		tb_tunnel_free(tunnel);
2223 	}
2224 
2225 	/* Re-create our tunnels now */
2226 	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
2227 		/* USB3 requires delay before it can be re-activated */
2228 		if (tb_tunnel_is_usb3(tunnel)) {
2229 			msleep(usb3_delay);
2230 			/* Only need to do it once */
2231 			usb3_delay = 0;
2232 		}
2233 		tb_tunnel_restart(tunnel);
2234 	}
2235 	if (!list_empty(&tcm->tunnel_list)) {
2236 		/*
2237 		 * the pcie links need some time to get going.
2238 		 * 100ms works for me...
2239 		 */
2240 		tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n");
2241 		msleep(100);
2242 	}
2243 	 /* Allow tb_handle_hotplug to progress events */
2244 	tcm->hotplug_active = true;
2245 	tb_dbg(tb, "resume finished\n");
2246 
2247 	return 0;
2248 }
2249 
tb_free_unplugged_xdomains(struct tb_switch * sw)2250 static int tb_free_unplugged_xdomains(struct tb_switch *sw)
2251 {
2252 	struct tb_port *port;
2253 	int ret = 0;
2254 
2255 	tb_switch_for_each_port(sw, port) {
2256 		if (tb_is_upstream_port(port))
2257 			continue;
2258 		if (port->xdomain && port->xdomain->is_unplugged) {
2259 			tb_retimer_remove_all(port);
2260 			tb_xdomain_remove(port->xdomain);
2261 			tb_port_unconfigure_xdomain(port);
2262 			port->xdomain = NULL;
2263 			ret++;
2264 		} else if (port->remote) {
2265 			ret += tb_free_unplugged_xdomains(port->remote->sw);
2266 		}
2267 	}
2268 
2269 	return ret;
2270 }
2271 
tb_freeze_noirq(struct tb * tb)2272 static int tb_freeze_noirq(struct tb *tb)
2273 {
2274 	struct tb_cm *tcm = tb_priv(tb);
2275 
2276 	tcm->hotplug_active = false;
2277 	return 0;
2278 }
2279 
tb_thaw_noirq(struct tb * tb)2280 static int tb_thaw_noirq(struct tb *tb)
2281 {
2282 	struct tb_cm *tcm = tb_priv(tb);
2283 
2284 	tcm->hotplug_active = true;
2285 	return 0;
2286 }
2287 
tb_complete(struct tb * tb)2288 static void tb_complete(struct tb *tb)
2289 {
2290 	/*
2291 	 * Release any unplugged XDomains and if there is a case where
2292 	 * another domain is swapped in place of unplugged XDomain we
2293 	 * need to run another rescan.
2294 	 */
2295 	mutex_lock(&tb->lock);
2296 	if (tb_free_unplugged_xdomains(tb->root_switch))
2297 		tb_scan_switch(tb->root_switch);
2298 	mutex_unlock(&tb->lock);
2299 }
2300 
tb_runtime_suspend(struct tb * tb)2301 static int tb_runtime_suspend(struct tb *tb)
2302 {
2303 	struct tb_cm *tcm = tb_priv(tb);
2304 
2305 	mutex_lock(&tb->lock);
2306 	tb_switch_suspend(tb->root_switch, true);
2307 	tcm->hotplug_active = false;
2308 	mutex_unlock(&tb->lock);
2309 
2310 	return 0;
2311 }
2312 
tb_remove_work(struct work_struct * work)2313 static void tb_remove_work(struct work_struct *work)
2314 {
2315 	struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work);
2316 	struct tb *tb = tcm_to_tb(tcm);
2317 
2318 	mutex_lock(&tb->lock);
2319 	if (tb->root_switch) {
2320 		tb_free_unplugged_children(tb->root_switch);
2321 		tb_free_unplugged_xdomains(tb->root_switch);
2322 	}
2323 	mutex_unlock(&tb->lock);
2324 }
2325 
tb_runtime_resume(struct tb * tb)2326 static int tb_runtime_resume(struct tb *tb)
2327 {
2328 	struct tb_cm *tcm = tb_priv(tb);
2329 	struct tb_tunnel *tunnel, *n;
2330 
2331 	mutex_lock(&tb->lock);
2332 	tb_switch_resume(tb->root_switch);
2333 	tb_free_invalid_tunnels(tb);
2334 	tb_restore_children(tb->root_switch);
2335 	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
2336 		tb_tunnel_restart(tunnel);
2337 	tcm->hotplug_active = true;
2338 	mutex_unlock(&tb->lock);
2339 
2340 	/*
2341 	 * Schedule cleanup of any unplugged devices. Run this in a
2342 	 * separate thread to avoid possible deadlock if the device
2343 	 * removal runtime resumes the unplugged device.
2344 	 */
2345 	queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50));
2346 	return 0;
2347 }
2348 
2349 static const struct tb_cm_ops tb_cm_ops = {
2350 	.start = tb_start,
2351 	.stop = tb_stop,
2352 	.suspend_noirq = tb_suspend_noirq,
2353 	.resume_noirq = tb_resume_noirq,
2354 	.freeze_noirq = tb_freeze_noirq,
2355 	.thaw_noirq = tb_thaw_noirq,
2356 	.complete = tb_complete,
2357 	.runtime_suspend = tb_runtime_suspend,
2358 	.runtime_resume = tb_runtime_resume,
2359 	.handle_event = tb_handle_event,
2360 	.disapprove_switch = tb_disconnect_pci,
2361 	.approve_switch = tb_tunnel_pci,
2362 	.approve_xdomain_paths = tb_approve_xdomain_paths,
2363 	.disconnect_xdomain_paths = tb_disconnect_xdomain_paths,
2364 };
2365 
2366 /*
2367  * During suspend the Thunderbolt controller is reset and all PCIe
2368  * tunnels are lost. The NHI driver will try to reestablish all tunnels
2369  * during resume. This adds device links between the tunneled PCIe
2370  * downstream ports and the NHI so that the device core will make sure
2371  * NHI is resumed first before the rest.
2372  */
tb_apple_add_links(struct tb_nhi * nhi)2373 static bool tb_apple_add_links(struct tb_nhi *nhi)
2374 {
2375 	struct pci_dev *upstream, *pdev;
2376 	bool ret;
2377 
2378 	if (!x86_apple_machine)
2379 		return false;
2380 
2381 	switch (nhi->pdev->device) {
2382 	case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
2383 	case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
2384 	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
2385 	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
2386 		break;
2387 	default:
2388 		return false;
2389 	}
2390 
2391 	upstream = pci_upstream_bridge(nhi->pdev);
2392 	while (upstream) {
2393 		if (!pci_is_pcie(upstream))
2394 			return false;
2395 		if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM)
2396 			break;
2397 		upstream = pci_upstream_bridge(upstream);
2398 	}
2399 
2400 	if (!upstream)
2401 		return false;
2402 
2403 	/*
2404 	 * For each hotplug downstream port, create add device link
2405 	 * back to NHI so that PCIe tunnels can be re-established after
2406 	 * sleep.
2407 	 */
2408 	ret = false;
2409 	for_each_pci_bridge(pdev, upstream->subordinate) {
2410 		const struct device_link *link;
2411 
2412 		if (!pci_is_pcie(pdev))
2413 			continue;
2414 		if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM ||
2415 		    !pdev->is_hotplug_bridge)
2416 			continue;
2417 
2418 		link = device_link_add(&pdev->dev, &nhi->pdev->dev,
2419 				       DL_FLAG_AUTOREMOVE_SUPPLIER |
2420 				       DL_FLAG_PM_RUNTIME);
2421 		if (link) {
2422 			dev_dbg(&nhi->pdev->dev, "created link from %s\n",
2423 				dev_name(&pdev->dev));
2424 			ret = true;
2425 		} else {
2426 			dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
2427 				 dev_name(&pdev->dev));
2428 		}
2429 	}
2430 
2431 	return ret;
2432 }
2433 
tb_probe(struct tb_nhi * nhi)2434 struct tb *tb_probe(struct tb_nhi *nhi)
2435 {
2436 	struct tb_cm *tcm;
2437 	struct tb *tb;
2438 
2439 	tb = tb_domain_alloc(nhi, TB_TIMEOUT, sizeof(*tcm));
2440 	if (!tb)
2441 		return NULL;
2442 
2443 	if (tb_acpi_may_tunnel_pcie())
2444 		tb->security_level = TB_SECURITY_USER;
2445 	else
2446 		tb->security_level = TB_SECURITY_NOPCIE;
2447 
2448 	tb->cm_ops = &tb_cm_ops;
2449 
2450 	tcm = tb_priv(tb);
2451 	INIT_LIST_HEAD(&tcm->tunnel_list);
2452 	INIT_LIST_HEAD(&tcm->dp_resources);
2453 	INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work);
2454 	tb_init_bandwidth_groups(tcm);
2455 
2456 	tb_dbg(tb, "using software connection manager\n");
2457 
2458 	/*
2459 	 * Device links are needed to make sure we establish tunnels
2460 	 * before the PCIe/USB stack is resumed so complain here if we
2461 	 * found them missing.
2462 	 */
2463 	if (!tb_apple_add_links(nhi) && !tb_acpi_add_links(nhi))
2464 		tb_warn(tb, "device links to tunneled native ports are missing!\n");
2465 
2466 	return tb;
2467 }
2468