drivers/thunderbolt/path.c

3  * Thunderbolt driver - path/tunnel functionality
50 			tb_port_warn(port, "failed to read path at %d\n", hopid);
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;
118 		 * so in that case find a path that ends on @dst with
136 			tb_port_warn(p, "failed to read path at %d\n", h);
140 		/* If the hop is not enabled we got an incomplete path */
153 	path = kzalloc(sizeof(*path), GFP_KERNEL);
154 	if (!path)
157 	path->name = name;
158 	path->tb = src->sw->tb;
159 	path->path_length = num_hops;
160 	path->activated = true;
161 	path->alloc_hopid = alloc_hopid;
163 	path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);
164 	if (!path->hops) {
165 		kfree(path);
169 	tb_dbg(path->tb, "discovering %s path starting from %llx:%u\n",
170 	       path->name, tb_route(src->sw), src->port);
182 			tb_port_warn(p, "failed to read path at %d\n", h);
198 		path->hops[i].in_port = p;
199 		path->hops[i].in_hop_index = h;
200 		path->hops[i].in_counter_index = -1;
201 		path->hops[i].out_port = out_port;
202 		path->hops[i].next_hop_index = next_hop;
204 		tb_dump_hop(&path->hops[i], &hop);
210 	tb_dbg(path->tb, "path discovery complete\n");
211 	return path;
214 	tb_port_warn(src, "failed to discover path starting at HopID %d\n",
216 	tb_path_free(path);
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;
248 	path = kzalloc(sizeof(*path), GFP_KERNEL);
249 	if (!path)
263 		kfree(path);
270 	path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL);
271 	if (!path->hops) {
272 		kfree(path);
276 	path->alloc_hopid = true;
332 		path->hops[i].in_hop_index = in_hopid;
333 		path->hops[i].in_port = in_port;
334 		path->hops[i].in_counter_index = -1;
335 		path->hops[i].out_port = out_port;
336 		path->hops[i].next_hop_index = out_hopid;
341 	path->tb = tb;
342 	path->path_length = num_hops;
343 	path->name = name;
345 	return path;
348 	tb_path_free(path);
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)
360 	if (path->alloc_hopid) {
363 		for (i = 0; i < path->path_length; i++) {
364 			const struct tb_path_hop *hop = &path->hops[i];
375 	kfree(path->hops);
376 	kfree(path);
379 static void __tb_path_deallocate_nfc(struct tb_path *path, int first_hop)
382 	for (i = first_hop; i < path->path_length; i++) {
383 		res = tb_port_add_nfc_credits(path->hops[i].in_port,
384 					      -path->hops[i].nfc_credits);
386 			tb_port_warn(path->hops[i].in_port,
399 	/* Disable the path */
450  * tb_path_deactivate_hop() - Deactivate one path in path config space
452  * @hop_index: HopID of the path to be cleared
454  * This deactivates or clears a single path config space entry at
462 static void __tb_path_deactivate_hops(struct tb_path *path, int first_hop)
466 	for (i = first_hop; i < path->path_length; i++) {
467 		res = __tb_path_deactivate_hop(path->hops[i].in_port,
468 					       path->hops[i].in_hop_index,
469 					       path->clear_fc);
471 			tb_port_warn(path->hops[i].in_port,
473 				     i, path->hops[i].in_hop_index);
477 void tb_path_deactivate(struct tb_path *path)
479 	if (!path->activated) {
480 		tb_WARN(path->tb, "trying to deactivate an inactive path\n");
483 	tb_dbg(path->tb,
484 	       "deactivating %s path from %llx:%u to %llx:%u\n",
485 	       path->name, tb_route(path->hops[0].in_port->sw),
486 	       path->hops[0].in_port->port,
487 	       tb_route(path->hops[path->path_length - 1].out_port->sw),
488 	       path->hops[path->path_length - 1].out_port->port);
489 	__tb_path_deactivate_hops(path, 0);
490 	__tb_path_deallocate_nfc(path, 0);
491 	path->activated = false;
495  * tb_path_activate() - activate a path
496  * @path: Path to activate
498  * Activate a path starting with the last hop and iterating backwards. The
499  * caller must fill path->hops before calling tb_path_activate().
503 int tb_path_activate(struct tb_path *path)
507 	if (path->activated) {
508 		tb_WARN(path->tb, "trying to activate already activated path\n");
512 	tb_dbg(path->tb,
513 	       "activating %s path from %llx:%u to %llx:%u\n",
514 	       path->name, tb_route(path->hops[0].in_port->sw),
515 	       path->hops[0].in_port->port,
516 	       tb_route(path->hops[path->path_length - 1].out_port->sw),
517 	       path->hops[path->path_length - 1].out_port->port);
520 	for (i = path->path_length - 1; i >= 0; i--) {
521 		if (path->hops[i].in_counter_index == -1)
523 		res = tb_port_clear_counter(path->hops[i].in_port,
524 					    path->hops[i].in_counter_index);
530 	for (i = path->path_length - 1; i >= 0; i--) {
531 		res = tb_port_add_nfc_credits(path->hops[i].in_port,
532 					      path->hops[i].nfc_credits);
534 			__tb_path_deallocate_nfc(path, i);
540 	for (i = path->path_length - 1; i >= 0; i--) {
544 		__tb_path_deactivate_hop(path->hops[i].in_port,
545 				path->hops[i].in_hop_index, path->clear_fc);
548 		hop.next_hop = path->hops[i].next_hop_index;
549 		hop.out_port = path->hops[i].out_port->port;
550 		hop.initial_credits = path->hops[i].initial_credits;
551 		hop.pmps = path->hops[i].pm_support;
556 		out_mask = (i == path->path_length - 1) ?
559 		hop.weight = path->weight;
561 		hop.priority = path->priority;
562 		hop.drop_packages = path->drop_packages;
563 		hop.counter = path->hops[i].in_counter_index;
564 		hop.counter_enable = path->hops[i].in_counter_index != -1;
565 		hop.ingress_fc = path->ingress_fc_enable & in_mask;
566 		hop.egress_fc = path->egress_fc_enable & out_mask;
567 		hop.ingress_shared_buffer = path->ingress_shared_buffer
569 		hop.egress_shared_buffer = path->egress_shared_buffer
573 		tb_port_dbg(path->hops[i].in_port, "Writing hop %d\n", i);
574 		tb_dump_hop(&path->hops[i], &hop);
575 		res = tb_port_write(path->hops[i].in_port, &hop, TB_CFG_HOPS,
576 				    2 * path->hops[i].in_hop_index, 2);
578 			__tb_path_deactivate_hops(path, i);
579 			__tb_path_deallocate_nfc(path, 0);
583 	path->activated = true;
584 	tb_dbg(path->tb, "path activation complete\n");
587 	tb_WARN(path->tb, "path activation failed\n");
592  * tb_path_is_invalid() - check whether any ports on the path are invalid
593  * @path: Path to check
595  * Return: Returns true if the path is invalid, false otherwise.
597 bool tb_path_is_invalid(struct tb_path *path)
600 	for (i = 0; i < path->path_length; i++) {
601 		if (path->hops[i].in_port->sw->is_unplugged)
603 		if (path->hops[i].out_port->sw->is_unplugged)
610  * tb_path_port_on_path() - Does the path go through certain port
611  * @path: Path to check
614  * Goes over all hops on path and checks if @port is any of them.
617 bool tb_path_port_on_path(const struct tb_path *path, const struct tb_port *port)
621 	for (i = 0; i < path->path_length; i++) {
622 		if (path->hops[i].in_port == port ||
623 		    path->hops[i].out_port == port)