3  * Thunderbolt driver - path/tunnel functionality
50 			tb_port_warn(port, "failed to read path at %d\n", hopid);  in tb_path_find_dst_port()
81  * tb_path_discover() - Discover a path
82  * @src: First input port of a path
83  * @src_hopid: Starting HopID of a path (%-1 if don't care)
84  * @dst: Expected destination port of the path (%NULL if don't care)
87  * @name: Name of the path
90  * Follows a path starting from @src and @src_hopid to the last output
91  * port of the path. Allocates HopIDs for the visited ports (if
92  * @alloc_hopid is true). Call tb_path_free() to release the path and
93  * allocated HopIDs when the path is not needed anymore.
96  * that the @dst port is the expected one. If it is not, the path can be
99  * Return: Discovered path on success, %NULL in case of failure
108 	struct tb_path *path;  in tb_path_discover()  local
118 		 * so in that case find a path that ends on @dst with  in tb_path_discover()
136 			tb_port_warn(p, "failed to read path at %d\n", h);  in tb_path_discover()
140 		/* If the hop is not enabled we got an incomplete path */  in tb_path_discover()
153 	path = kzalloc(sizeof(*path), GFP_KERNEL);  in tb_path_discover()
154 	if (!path)  in tb_path_discover()
157 	path->name = name;  in tb_path_discover()
158 	path->tb = src->sw->tb;  in tb_path_discover()
159 	path->path_length = num_hops;  in tb_path_discover()
160 	path->activated = true;  in tb_path_discover()
161 	path->alloc_hopid = alloc_hopid;  in tb_path_discover()
163 	path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);  in tb_path_discover()
164 	if (!path->hops) {  in tb_path_discover()
165 		kfree(path);  in tb_path_discover()
169 	tb_dbg(path->tb, "discovering %s path starting from %llx:%u\n",  in tb_path_discover()
170 	       path->name, tb_route(src->sw), src->port);  in tb_path_discover()
182 			tb_port_warn(p, "failed to read path at %d\n", h);  in tb_path_discover()
198 		path->hops[i].in_port = p;  in tb_path_discover()
199 		path->hops[i].in_hop_index = h;  in tb_path_discover()
200 		path->hops[i].in_counter_index = -1;  in tb_path_discover()
201 		path->hops[i].out_port = out_port;  in tb_path_discover()
202 		path->hops[i].next_hop_index = next_hop;  in tb_path_discover()
204 		tb_dump_hop(&path->hops[i], &hop);  in tb_path_discover()
210 	tb_dbg(path->tb, "path discovery complete\n");  in tb_path_discover()
211 	return path;  in tb_path_discover()
214 	tb_port_warn(src, "failed to discover path starting at HopID %d\n",  in tb_path_discover()
216 	tb_path_free(path);  in tb_path_discover()
221  * tb_path_alloc() - allocate a thunderbolt path between two ports
223  * @src: Source port of the path
224  * @src_hopid: HopID used for the first ingress port in the path
225  * @dst: Destination port of the path
226  * @dst_hopid: HopID used for the last egress port in the path
227  * @link_nr: Preferred link if there are dual links on the path
228  * @name: Name of the path
230  * Creates path between two ports starting with given @src_hopid. Reserves
233  * links on the path, prioritizes using @link_nr but takes into account
244 	struct tb_path *path;  in tb_path_alloc()  local
248 	path = kzalloc(sizeof(*path), GFP_KERNEL);  in tb_path_alloc()
249 	if (!path)  in tb_path_alloc()
263 		kfree(path);  in tb_path_alloc()
270 	path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);  in tb_path_alloc()
271 	if (!path->hops) {  in tb_path_alloc()
272 		kfree(path);  in tb_path_alloc()
276 	path->alloc_hopid = true;  in tb_path_alloc()
332 		path->hops[i].in_hop_index = in_hopid;  in tb_path_alloc()
333 		path->hops[i].in_port = in_port;  in tb_path_alloc()
334 		path->hops[i].in_counter_index = -1;  in tb_path_alloc()
335 		path->hops[i].out_port = out_port;  in tb_path_alloc()
336 		path->hops[i].next_hop_index = out_hopid;  in tb_path_alloc()
341 	path->tb = tb;  in tb_path_alloc()
342 	path->path_length = num_hops;  in tb_path_alloc()
343 	path->name = name;  in tb_path_alloc()
345 	return path;  in tb_path_alloc()
348 	tb_path_free(path);  in tb_path_alloc()
353  * tb_path_free() - free a path
354  * @path: Path to free
356  * Frees a path. The path does not need to be deactivated.
358 void tb_path_free(struct tb_path *path)  in tb_path_free()  argument
360 	if (path->alloc_hopid) {  in tb_path_free()
363 		for (i = 0; i < path->path_length; i++) {  in tb_path_free()
364 			const struct tb_path_hop *hop = &path->hops[i];  in tb_path_free()
375 	kfree(path->hops);  in tb_path_free()
376 	kfree(path);  in tb_path_free()
379 static void __tb_path_deallocate_nfc(struct tb_path *path, int first_hop)  in __tb_path_deallocate_nfc()  argument
382 	for (i = first_hop; i < path->path_length; i++) {  in __tb_path_deallocate_nfc()
383 		res = tb_port_add_nfc_credits(path->hops[i].in_port,  in __tb_path_deallocate_nfc()
384 					      -path->hops[i].nfc_credits);  in __tb_path_deallocate_nfc()
386 			tb_port_warn(path->hops[i].in_port,  in __tb_path_deallocate_nfc()
399 	/* Disable the path */  in __tb_path_deactivate_hop()
449 static void __tb_path_deactivate_hops(struct tb_path *path, int first_hop)  in __tb_path_deactivate_hops()  argument
453 	for (i = first_hop; i < path->path_length; i++) {  in __tb_path_deactivate_hops()
454 		res = __tb_path_deactivate_hop(path->hops[i].in_port,  in __tb_path_deactivate_hops()
455 					       path->hops[i].in_hop_index,  in __tb_path_deactivate_hops()
456 					       path->clear_fc);  in __tb_path_deactivate_hops()
458 			tb_port_warn(path->hops[i].in_port,  in __tb_path_deactivate_hops()
460 				     i, path->hops[i].in_hop_index);  in __tb_path_deactivate_hops()
464 void tb_path_deactivate(struct tb_path *path)  in tb_path_deactivate()  argument
466 	if (!path->activated) {  in tb_path_deactivate()
467 		tb_WARN(path->tb, "trying to deactivate an inactive path\n");  in tb_path_deactivate()
470 	tb_dbg(path->tb,  in tb_path_deactivate()
471 	       "deactivating %s path from %llx:%u to %llx:%u\n",  in tb_path_deactivate()
472 	       path->name, tb_route(path->hops[0].in_port->sw),  in tb_path_deactivate()
473 	       path->hops[0].in_port->port,  in tb_path_deactivate()
474 	       tb_route(path->hops[path->path_length - 1].out_port->sw),  in tb_path_deactivate()
475 	       path->hops[path->path_length - 1].out_port->port);  in tb_path_deactivate()
476 	__tb_path_deactivate_hops(path, 0);  in tb_path_deactivate()
477 	__tb_path_deallocate_nfc(path, 0);  in tb_path_deactivate()
478 	path->activated = false;  in tb_path_deactivate()
482  * tb_path_activate() - activate a path
483  * @path: Path to activate
485  * Activate a path starting with the last hop and iterating backwards. The
486  * caller must fill path->hops before calling tb_path_activate().
490 int tb_path_activate(struct tb_path *path)  in tb_path_activate()  argument
494 	if (path->activated) {  in tb_path_activate()
495 		tb_WARN(path->tb, "trying to activate already activated path\n");  in tb_path_activate()
499 	tb_dbg(path->tb,  in tb_path_activate()
500 	       "activating %s path from %llx:%u to %llx:%u\n",  in tb_path_activate()
501 	       path->name, tb_route(path->hops[0].in_port->sw),  in tb_path_activate()
502 	       path->hops[0].in_port->port,  in tb_path_activate()
503 	       tb_route(path->hops[path->path_length - 1].out_port->sw),  in tb_path_activate()
504 	       path->hops[path->path_length - 1].out_port->port);  in tb_path_activate()
507 	for (i = path->path_length - 1; i >= 0; i--) {  in tb_path_activate()
508 		if (path->hops[i].in_counter_index == -1)  in tb_path_activate()
510 		res = tb_port_clear_counter(path->hops[i].in_port,  in tb_path_activate()
511 					    path->hops[i].in_counter_index);  in tb_path_activate()
517 	for (i = path->path_length - 1; i >= 0; i--) {  in tb_path_activate()
518 		res = tb_port_add_nfc_credits(path->hops[i].in_port,  in tb_path_activate()
519 					      path->hops[i].nfc_credits);  in tb_path_activate()
521 			__tb_path_deallocate_nfc(path, i);  in tb_path_activate()
527 	for (i = path->path_length - 1; i >= 0; i--) {  in tb_path_activate()
531 		__tb_path_deactivate_hop(path->hops[i].in_port,  in tb_path_activate()
532 				path->hops[i].in_hop_index, path->clear_fc);  in tb_path_activate()
535 		hop.next_hop = path->hops[i].next_hop_index;  in tb_path_activate()
536 		hop.out_port = path->hops[i].out_port->port;  in tb_path_activate()
537 		hop.initial_credits = path->hops[i].initial_credits;  in tb_path_activate()
542 		out_mask = (i == path->path_length - 1) ?  in tb_path_activate()
545 		hop.weight = path->weight;  in tb_path_activate()
547 		hop.priority = path->priority;  in tb_path_activate()
548 		hop.drop_packages = path->drop_packages;  in tb_path_activate()
549 		hop.counter = path->hops[i].in_counter_index;  in tb_path_activate()
550 		hop.counter_enable = path->hops[i].in_counter_index != -1;  in tb_path_activate()
551 		hop.ingress_fc = path->ingress_fc_enable & in_mask;  in tb_path_activate()
552 		hop.egress_fc = path->egress_fc_enable & out_mask;  in tb_path_activate()
553 		hop.ingress_shared_buffer = path->ingress_shared_buffer  in tb_path_activate()
555 		hop.egress_shared_buffer = path->egress_shared_buffer  in tb_path_activate()
559 		tb_port_dbg(path->hops[i].in_port, "Writing hop %d\n", i);  in tb_path_activate()
560 		tb_dump_hop(&path->hops[i], &hop);  in tb_path_activate()
561 		res = tb_port_write(path->hops[i].in_port, &hop, TB_CFG_HOPS,  in tb_path_activate()
562 				    2 * path->hops[i].in_hop_index, 2);  in tb_path_activate()
564 			__tb_path_deactivate_hops(path, i);  in tb_path_activate()
565 			__tb_path_deallocate_nfc(path, 0);  in tb_path_activate()
569 	path->activated = true;  in tb_path_activate()
570 	tb_dbg(path->tb, "path activation complete\n");  in tb_path_activate()
573 	tb_WARN(path->tb, "path activation failed\n");  in tb_path_activate()
578  * tb_path_is_invalid() - check whether any ports on the path are invalid
579  * @path: Path to check
581  * Return: Returns true if the path is invalid, false otherwise.
583 bool tb_path_is_invalid(struct tb_path *path)  in tb_path_is_invalid()  argument
586 	for (i = 0; i < path->path_length; i++) {  in tb_path_is_invalid()
587 		if (path->hops[i].in_port->sw->is_unplugged)  in tb_path_is_invalid()
589 		if (path->hops[i].out_port->sw->is_unplugged)  in tb_path_is_invalid()
596  * tb_path_port_on_path() - Does the path go through certain port
597  * @path: Path to check
600  * Goes over all hops on path and checks if @port is any of them.
603 bool tb_path_port_on_path(const struct tb_path *path, const struct tb_port *port)  in tb_path_port_on_path()  argument
607 	for (i = 0; i < path->path_length; i++) {  in tb_path_port_on_path()
608 		if (path->hops[i].in_port == port ||  in tb_path_port_on_path()
609 		    path->hops[i].out_port == port)  in tb_path_port_on_path()