Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
520b6702 | 2 | /* |
0414bec5 | 3 | * Thunderbolt driver - path/tunnel functionality |
520b6702 AN |
4 | * |
5 | * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com> | |
0414bec5 | 6 | * Copyright (C) 2019, Intel Corporation |
520b6702 AN |
7 | */ |
8 | ||
9 | #include <linux/slab.h> | |
10 | #include <linux/errno.h> | |
49442693 MW |
11 | #include <linux/delay.h> |
12 | #include <linux/ktime.h> | |
520b6702 AN |
13 | |
14 | #include "tb.h" | |
15 | ||
6755156a | 16 | static void tb_dump_hop(const struct tb_path_hop *hop, const struct tb_regs_hop *regs) |
520b6702 | 17 | { |
6755156a MW |
18 | const struct tb_port *port = hop->in_port; |
19 | ||
20 | tb_port_dbg(port, " In HopID: %d => Out port: %d Out HopID: %d\n", | |
21 | hop->in_hop_index, regs->out_port, regs->next_hop); | |
daa5140f | 22 | tb_port_dbg(port, " Weight: %d Priority: %d Credits: %d Drop: %d\n", |
6755156a MW |
23 | regs->weight, regs->priority, |
24 | regs->initial_credits, regs->drop_packages); | |
daa5140f | 25 | tb_port_dbg(port, " Counter enabled: %d Counter index: %d\n", |
6755156a | 26 | regs->counter_enable, regs->counter); |
daa5140f | 27 | tb_port_dbg(port, " Flow Control (In/Eg): %d/%d Shared Buffer (In/Eg): %d/%d\n", |
6755156a MW |
28 | regs->ingress_fc, regs->egress_fc, |
29 | regs->ingress_shared_buffer, regs->egress_shared_buffer); | |
daa5140f | 30 | tb_port_dbg(port, " Unknown1: %#x Unknown2: %#x Unknown3: %#x\n", |
6755156a | 31 | regs->unknown1, regs->unknown2, regs->unknown3); |
520b6702 AN |
32 | } |
33 | ||
0414bec5 MW |
34 | static struct tb_port *tb_path_find_dst_port(struct tb_port *src, int src_hopid, |
35 | int dst_hopid) | |
36 | { | |
37 | struct tb_port *port, *out_port = NULL; | |
38 | struct tb_regs_hop hop; | |
39 | struct tb_switch *sw; | |
40 | int i, ret, hopid; | |
41 | ||
42 | hopid = src_hopid; | |
43 | port = src; | |
44 | ||
45 | for (i = 0; port && i < TB_PATH_MAX_HOPS; i++) { | |
46 | sw = port->sw; | |
47 | ||
48 | ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hopid, 2); | |
49 | if (ret) { | |
50 | tb_port_warn(port, "failed to read path at %d\n", hopid); | |
51 | return NULL; | |
52 | } | |
53 | ||
54 | if (!hop.enable) | |
55 | return NULL; | |
56 | ||
57 | out_port = &sw->ports[hop.out_port]; | |
58 | hopid = hop.next_hop; | |
59 | port = out_port->remote; | |
60 | } | |
61 | ||
62 | return out_port && hopid == dst_hopid ? out_port : NULL; | |
63 | } | |
64 | ||
65 | static int tb_path_find_src_hopid(struct tb_port *src, | |
66 | const struct tb_port *dst, int dst_hopid) | |
67 | { | |
68 | struct tb_port *out; | |
69 | int i; | |
70 | ||
71 | for (i = TB_PATH_MIN_HOPID; i <= src->config.max_in_hop_id; i++) { | |
72 | out = tb_path_find_dst_port(src, i, dst_hopid); | |
73 | if (out == dst) | |
74 | return i; | |
75 | } | |
76 | ||
77 | return 0; | |
78 | } | |
79 | ||
80 | /** | |
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) | |
85 | * @dst_hopid: HopID to the @dst (%-1 if don't care) | |
86 | * @last: Last port is filled here if not %NULL | |
87 | * @name: Name of the path | |
88 | * | |
89 | * Follows a path starting from @src and @src_hopid to the last output | |
90 | * port of the path. Allocates HopIDs for the visited ports. Call | |
91 | * tb_path_free() to release the path and allocated HopIDs when the path | |
92 | * is not needed anymore. | |
93 | * | |
94 | * Note function discovers also incomplete paths so caller should check | |
95 | * that the @dst port is the expected one. If it is not, the path can be | |
96 | * cleaned up by calling tb_path_deactivate() before tb_path_free(). | |
97 | * | |
98 | * Return: Discovered path on success, %NULL in case of failure | |
99 | */ | |
100 | struct tb_path *tb_path_discover(struct tb_port *src, int src_hopid, | |
101 | struct tb_port *dst, int dst_hopid, | |
102 | struct tb_port **last, const char *name) | |
103 | { | |
104 | struct tb_port *out_port; | |
105 | struct tb_regs_hop hop; | |
106 | struct tb_path *path; | |
107 | struct tb_switch *sw; | |
108 | struct tb_port *p; | |
109 | size_t num_hops; | |
110 | int ret, i, h; | |
111 | ||
112 | if (src_hopid < 0 && dst) { | |
113 | /* | |
114 | * For incomplete paths the intermediate HopID can be | |
115 | * different from the one used by the protocol adapter | |
116 | * so in that case find a path that ends on @dst with | |
117 | * matching @dst_hopid. That should give us the correct | |
118 | * HopID for the @src. | |
119 | */ | |
120 | src_hopid = tb_path_find_src_hopid(src, dst, dst_hopid); | |
121 | if (!src_hopid) | |
122 | return NULL; | |
123 | } | |
124 | ||
125 | p = src; | |
126 | h = src_hopid; | |
127 | num_hops = 0; | |
128 | ||
129 | for (i = 0; p && i < TB_PATH_MAX_HOPS; i++) { | |
130 | sw = p->sw; | |
131 | ||
132 | ret = tb_port_read(p, &hop, TB_CFG_HOPS, 2 * h, 2); | |
133 | if (ret) { | |
134 | tb_port_warn(p, "failed to read path at %d\n", h); | |
135 | return NULL; | |
136 | } | |
137 | ||
138 | /* If the hop is not enabled we got an incomplete path */ | |
139 | if (!hop.enable) | |
140 | break; | |
141 | ||
142 | out_port = &sw->ports[hop.out_port]; | |
143 | if (last) | |
144 | *last = out_port; | |
145 | ||
146 | h = hop.next_hop; | |
147 | p = out_port->remote; | |
148 | num_hops++; | |
149 | } | |
150 | ||
151 | path = kzalloc(sizeof(*path), GFP_KERNEL); | |
152 | if (!path) | |
153 | return NULL; | |
154 | ||
155 | path->name = name; | |
156 | path->tb = src->sw->tb; | |
157 | path->path_length = num_hops; | |
158 | path->activated = true; | |
159 | ||
160 | path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL); | |
161 | if (!path->hops) { | |
162 | kfree(path); | |
163 | return NULL; | |
164 | } | |
165 | ||
166 | p = src; | |
167 | h = src_hopid; | |
168 | ||
169 | for (i = 0; i < num_hops; i++) { | |
170 | int next_hop; | |
171 | ||
172 | sw = p->sw; | |
173 | ||
174 | ret = tb_port_read(p, &hop, TB_CFG_HOPS, 2 * h, 2); | |
175 | if (ret) { | |
176 | tb_port_warn(p, "failed to read path at %d\n", h); | |
177 | goto err; | |
178 | } | |
179 | ||
180 | if (tb_port_alloc_in_hopid(p, h, h) < 0) | |
181 | goto err; | |
182 | ||
183 | out_port = &sw->ports[hop.out_port]; | |
184 | next_hop = hop.next_hop; | |
185 | ||
186 | if (tb_port_alloc_out_hopid(out_port, next_hop, next_hop) < 0) { | |
187 | tb_port_release_in_hopid(p, h); | |
188 | goto err; | |
189 | } | |
190 | ||
191 | path->hops[i].in_port = p; | |
192 | path->hops[i].in_hop_index = h; | |
193 | path->hops[i].in_counter_index = -1; | |
194 | path->hops[i].out_port = out_port; | |
195 | path->hops[i].next_hop_index = next_hop; | |
196 | ||
197 | h = next_hop; | |
198 | p = out_port->remote; | |
199 | } | |
200 | ||
201 | return path; | |
202 | ||
203 | err: | |
204 | tb_port_warn(src, "failed to discover path starting at HopID %d\n", | |
205 | src_hopid); | |
206 | tb_path_free(path); | |
207 | return NULL; | |
208 | } | |
209 | ||
520b6702 | 210 | /** |
8c7acaaf MW |
211 | * tb_path_alloc() - allocate a thunderbolt path between two ports |
212 | * @tb: Domain pointer | |
213 | * @src: Source port of the path | |
214 | * @src_hopid: HopID used for the first ingress port in the path | |
215 | * @dst: Destination port of the path | |
216 | * @dst_hopid: HopID used for the last egress port in the path | |
217 | * @link_nr: Preferred link if there are dual links on the path | |
218 | * @name: Name of the path | |
219 | * | |
220 | * Creates path between two ports starting with given @src_hopid. Reserves | |
221 | * HopIDs for each port (they can be different from @src_hopid depending on | |
222 | * how many HopIDs each port already have reserved). If there are dual | |
223 | * links on the path, prioritizes using @link_nr. | |
520b6702 AN |
224 | * |
225 | * Return: Returns a tb_path on success or NULL on failure. | |
226 | */ | |
8c7acaaf MW |
227 | struct tb_path *tb_path_alloc(struct tb *tb, struct tb_port *src, int src_hopid, |
228 | struct tb_port *dst, int dst_hopid, int link_nr, | |
229 | const char *name) | |
520b6702 | 230 | { |
8c7acaaf MW |
231 | struct tb_port *in_port, *out_port; |
232 | int in_hopid, out_hopid; | |
233 | struct tb_path *path; | |
234 | size_t num_hops; | |
235 | int i, ret; | |
236 | ||
237 | path = kzalloc(sizeof(*path), GFP_KERNEL); | |
520b6702 AN |
238 | if (!path) |
239 | return NULL; | |
8c7acaaf MW |
240 | |
241 | /* | |
242 | * Number of hops on a path is the distance between the two | |
243 | * switches plus the source adapter port. | |
244 | */ | |
245 | num_hops = abs(tb_route_length(tb_route(src->sw)) - | |
246 | tb_route_length(tb_route(dst->sw))) + 1; | |
247 | ||
520b6702 AN |
248 | path->hops = kcalloc(num_hops, sizeof(*path->hops), GFP_KERNEL); |
249 | if (!path->hops) { | |
250 | kfree(path); | |
251 | return NULL; | |
252 | } | |
8c7acaaf MW |
253 | |
254 | in_hopid = src_hopid; | |
255 | out_port = NULL; | |
256 | ||
257 | for (i = 0; i < num_hops; i++) { | |
258 | in_port = tb_next_port_on_path(src, dst, out_port); | |
259 | if (!in_port) | |
260 | goto err; | |
261 | ||
262 | if (in_port->dual_link_port && in_port->link_nr != link_nr) | |
263 | in_port = in_port->dual_link_port; | |
264 | ||
265 | ret = tb_port_alloc_in_hopid(in_port, in_hopid, in_hopid); | |
266 | if (ret < 0) | |
267 | goto err; | |
268 | in_hopid = ret; | |
269 | ||
270 | out_port = tb_next_port_on_path(src, dst, in_port); | |
271 | if (!out_port) | |
272 | goto err; | |
273 | ||
274 | if (out_port->dual_link_port && out_port->link_nr != link_nr) | |
275 | out_port = out_port->dual_link_port; | |
276 | ||
277 | if (i == num_hops - 1) | |
278 | ret = tb_port_alloc_out_hopid(out_port, dst_hopid, | |
279 | dst_hopid); | |
280 | else | |
281 | ret = tb_port_alloc_out_hopid(out_port, -1, -1); | |
282 | ||
283 | if (ret < 0) | |
284 | goto err; | |
285 | out_hopid = ret; | |
286 | ||
287 | path->hops[i].in_hop_index = in_hopid; | |
288 | path->hops[i].in_port = in_port; | |
289 | path->hops[i].in_counter_index = -1; | |
290 | path->hops[i].out_port = out_port; | |
291 | path->hops[i].next_hop_index = out_hopid; | |
292 | ||
293 | in_hopid = out_hopid; | |
294 | } | |
295 | ||
520b6702 AN |
296 | path->tb = tb; |
297 | path->path_length = num_hops; | |
8c7acaaf MW |
298 | path->name = name; |
299 | ||
520b6702 | 300 | return path; |
8c7acaaf MW |
301 | |
302 | err: | |
303 | tb_path_free(path); | |
304 | return NULL; | |
520b6702 AN |
305 | } |
306 | ||
307 | /** | |
ab9f31cf MW |
308 | * tb_path_free() - free a path |
309 | * @path: Path to free | |
310 | * | |
311 | * Frees a path. The path does not need to be deactivated. | |
520b6702 AN |
312 | */ |
313 | void tb_path_free(struct tb_path *path) | |
314 | { | |
8c7acaaf MW |
315 | int i; |
316 | ||
8c7acaaf MW |
317 | for (i = 0; i < path->path_length; i++) { |
318 | const struct tb_path_hop *hop = &path->hops[i]; | |
319 | ||
320 | if (hop->in_port) | |
321 | tb_port_release_in_hopid(hop->in_port, | |
322 | hop->in_hop_index); | |
323 | if (hop->out_port) | |
324 | tb_port_release_out_hopid(hop->out_port, | |
325 | hop->next_hop_index); | |
326 | } | |
327 | ||
520b6702 AN |
328 | kfree(path->hops); |
329 | kfree(path); | |
330 | } | |
331 | ||
332 | static void __tb_path_deallocate_nfc(struct tb_path *path, int first_hop) | |
333 | { | |
334 | int i, res; | |
335 | for (i = first_hop; i < path->path_length; i++) { | |
336 | res = tb_port_add_nfc_credits(path->hops[i].in_port, | |
337 | -path->nfc_credits); | |
338 | if (res) | |
339 | tb_port_warn(path->hops[i].in_port, | |
340 | "nfc credits deallocation failed for hop %d\n", | |
341 | i); | |
342 | } | |
343 | } | |
344 | ||
44242d6c MW |
345 | static int __tb_path_deactivate_hop(struct tb_port *port, int hop_index, |
346 | bool clear_fc) | |
49442693 MW |
347 | { |
348 | struct tb_regs_hop hop; | |
349 | ktime_t timeout; | |
350 | int ret; | |
351 | ||
352 | /* Disable the path */ | |
353 | ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); | |
354 | if (ret) | |
355 | return ret; | |
356 | ||
357 | /* Already disabled */ | |
358 | if (!hop.enable) | |
359 | return 0; | |
360 | ||
361 | hop.enable = 0; | |
362 | ||
363 | ret = tb_port_write(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); | |
364 | if (ret) | |
365 | return ret; | |
366 | ||
367 | /* Wait until it is drained */ | |
368 | timeout = ktime_add_ms(ktime_get(), 500); | |
369 | do { | |
370 | ret = tb_port_read(port, &hop, TB_CFG_HOPS, 2 * hop_index, 2); | |
371 | if (ret) | |
372 | return ret; | |
373 | ||
44242d6c MW |
374 | if (!hop.pending) { |
375 | if (clear_fc) { | |
376 | /* Clear flow control */ | |
377 | hop.ingress_fc = 0; | |
378 | hop.egress_fc = 0; | |
379 | hop.ingress_shared_buffer = 0; | |
380 | hop.egress_shared_buffer = 0; | |
381 | ||
382 | return tb_port_write(port, &hop, TB_CFG_HOPS, | |
383 | 2 * hop_index, 2); | |
384 | } | |
385 | ||
49442693 | 386 | return 0; |
44242d6c | 387 | } |
49442693 MW |
388 | |
389 | usleep_range(10, 20); | |
390 | } while (ktime_before(ktime_get(), timeout)); | |
391 | ||
392 | return -ETIMEDOUT; | |
393 | } | |
394 | ||
520b6702 AN |
395 | static void __tb_path_deactivate_hops(struct tb_path *path, int first_hop) |
396 | { | |
397 | int i, res; | |
49442693 | 398 | |
520b6702 | 399 | for (i = first_hop; i < path->path_length; i++) { |
49442693 | 400 | res = __tb_path_deactivate_hop(path->hops[i].in_port, |
44242d6c MW |
401 | path->hops[i].in_hop_index, |
402 | path->clear_fc); | |
49442693 | 403 | if (res && res != -ENODEV) |
520b6702 AN |
404 | tb_port_warn(path->hops[i].in_port, |
405 | "hop deactivation failed for hop %d, index %d\n", | |
406 | i, path->hops[i].in_hop_index); | |
407 | } | |
408 | } | |
409 | ||
410 | void tb_path_deactivate(struct tb_path *path) | |
411 | { | |
412 | if (!path->activated) { | |
413 | tb_WARN(path->tb, "trying to deactivate an inactive path\n"); | |
414 | return; | |
415 | } | |
8c7acaaf MW |
416 | tb_dbg(path->tb, |
417 | "deactivating %s path from %llx:%x to %llx:%x\n", | |
418 | path->name, tb_route(path->hops[0].in_port->sw), | |
419 | path->hops[0].in_port->port, | |
420 | tb_route(path->hops[path->path_length - 1].out_port->sw), | |
421 | path->hops[path->path_length - 1].out_port->port); | |
520b6702 AN |
422 | __tb_path_deactivate_hops(path, 0); |
423 | __tb_path_deallocate_nfc(path, 0); | |
424 | path->activated = false; | |
425 | } | |
426 | ||
427 | /** | |
428 | * tb_path_activate() - activate a path | |
429 | * | |
430 | * Activate a path starting with the last hop and iterating backwards. The | |
431 | * caller must fill path->hops before calling tb_path_activate(). | |
432 | * | |
433 | * Return: Returns 0 on success or an error code on failure. | |
434 | */ | |
435 | int tb_path_activate(struct tb_path *path) | |
436 | { | |
437 | int i, res; | |
438 | enum tb_path_port out_mask, in_mask; | |
439 | if (path->activated) { | |
440 | tb_WARN(path->tb, "trying to activate already activated path\n"); | |
441 | return -EINVAL; | |
442 | } | |
443 | ||
8c7acaaf MW |
444 | tb_dbg(path->tb, |
445 | "activating %s path from %llx:%x to %llx:%x\n", | |
446 | path->name, tb_route(path->hops[0].in_port->sw), | |
447 | path->hops[0].in_port->port, | |
448 | tb_route(path->hops[path->path_length - 1].out_port->sw), | |
449 | path->hops[path->path_length - 1].out_port->port); | |
520b6702 AN |
450 | |
451 | /* Clear counters. */ | |
452 | for (i = path->path_length - 1; i >= 0; i--) { | |
453 | if (path->hops[i].in_counter_index == -1) | |
454 | continue; | |
455 | res = tb_port_clear_counter(path->hops[i].in_port, | |
456 | path->hops[i].in_counter_index); | |
457 | if (res) | |
458 | goto err; | |
459 | } | |
460 | ||
461 | /* Add non flow controlled credits. */ | |
462 | for (i = path->path_length - 1; i >= 0; i--) { | |
463 | res = tb_port_add_nfc_credits(path->hops[i].in_port, | |
464 | path->nfc_credits); | |
465 | if (res) { | |
466 | __tb_path_deallocate_nfc(path, i); | |
467 | goto err; | |
468 | } | |
469 | } | |
470 | ||
471 | /* Activate hops. */ | |
472 | for (i = path->path_length - 1; i >= 0; i--) { | |
72ad366f AN |
473 | struct tb_regs_hop hop = { 0 }; |
474 | ||
0414bec5 MW |
475 | /* If it is left active deactivate it first */ |
476 | __tb_path_deactivate_hop(path->hops[i].in_port, | |
44242d6c | 477 | path->hops[i].in_hop_index, path->clear_fc); |
520b6702 AN |
478 | |
479 | /* dword 0 */ | |
480 | hop.next_hop = path->hops[i].next_hop_index; | |
481 | hop.out_port = path->hops[i].out_port->port; | |
0414bec5 | 482 | hop.initial_credits = path->hops[i].initial_credits; |
520b6702 AN |
483 | hop.unknown1 = 0; |
484 | hop.enable = 1; | |
485 | ||
486 | /* dword 1 */ | |
487 | out_mask = (i == path->path_length - 1) ? | |
488 | TB_PATH_DESTINATION : TB_PATH_INTERNAL; | |
489 | in_mask = (i == 0) ? TB_PATH_SOURCE : TB_PATH_INTERNAL; | |
490 | hop.weight = path->weight; | |
491 | hop.unknown2 = 0; | |
492 | hop.priority = path->priority; | |
493 | hop.drop_packages = path->drop_packages; | |
494 | hop.counter = path->hops[i].in_counter_index; | |
495 | hop.counter_enable = path->hops[i].in_counter_index != -1; | |
496 | hop.ingress_fc = path->ingress_fc_enable & in_mask; | |
497 | hop.egress_fc = path->egress_fc_enable & out_mask; | |
498 | hop.ingress_shared_buffer = path->ingress_shared_buffer | |
499 | & in_mask; | |
500 | hop.egress_shared_buffer = path->egress_shared_buffer | |
501 | & out_mask; | |
502 | hop.unknown3 = 0; | |
503 | ||
6755156a MW |
504 | tb_port_dbg(path->hops[i].in_port, "Writing hop %d\n", i); |
505 | tb_dump_hop(&path->hops[i], &hop); | |
520b6702 AN |
506 | res = tb_port_write(path->hops[i].in_port, &hop, TB_CFG_HOPS, |
507 | 2 * path->hops[i].in_hop_index, 2); | |
508 | if (res) { | |
509 | __tb_path_deactivate_hops(path, i); | |
510 | __tb_path_deallocate_nfc(path, 0); | |
511 | goto err; | |
512 | } | |
513 | } | |
514 | path->activated = true; | |
62efe699 | 515 | tb_dbg(path->tb, "path activation complete\n"); |
520b6702 AN |
516 | return 0; |
517 | err: | |
518 | tb_WARN(path->tb, "path activation failed\n"); | |
519 | return res; | |
520 | } | |
521 | ||
522 | /** | |
523 | * tb_path_is_invalid() - check whether any ports on the path are invalid | |
524 | * | |
525 | * Return: Returns true if the path is invalid, false otherwise. | |
526 | */ | |
527 | bool tb_path_is_invalid(struct tb_path *path) | |
528 | { | |
529 | int i = 0; | |
530 | for (i = 0; i < path->path_length; i++) { | |
531 | if (path->hops[i].in_port->sw->is_unplugged) | |
532 | return true; | |
533 | if (path->hops[i].out_port->sw->is_unplugged) | |
534 | return true; | |
535 | } | |
536 | return false; | |
537 | } |