1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Thunderbolt driver - control channel and configuration commands |
4 | * |
5 | * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com> |
6 | * Copyright (C) 2018, Intel Corporation |
7 | */ |
8 | |
9 | #include <linux/crc32.h> |
10 | #include <linux/delay.h> |
11 | #include <linux/slab.h> |
12 | #include <linux/pci.h> |
13 | #include <linux/dmapool.h> |
14 | #include <linux/workqueue.h> |
15 | |
16 | #include "ctl.h" |
17 | |
18 | #define CREATE_TRACE_POINTS |
19 | #include "trace.h" |
20 | |
21 | #define TB_CTL_RX_PKG_COUNT 10 |
22 | #define TB_CTL_RETRIES 4 |
23 | |
24 | /** |
25 | * struct tb_ctl - Thunderbolt control channel |
26 | * @nhi: Pointer to the NHI structure |
27 | * @tx: Transmit ring |
28 | * @rx: Receive ring |
29 | * @frame_pool: DMA pool for control messages |
30 | * @rx_packets: Received control messages |
31 | * @request_queue_lock: Lock protecting @request_queue |
32 | * @request_queue: List of outstanding requests |
33 | * @running: Is the control channel running at the moment |
34 | * @timeout_msec: Default timeout for non-raw control messages |
35 | * @callback: Callback called when hotplug message is received |
36 | * @callback_data: Data passed to @callback |
37 | * @index: Domain number. This will be output with the trace record. |
38 | */ |
39 | struct tb_ctl { |
40 | struct tb_nhi *nhi; |
41 | struct tb_ring *tx; |
42 | struct tb_ring *rx; |
43 | |
44 | struct dma_pool *frame_pool; |
45 | struct ctl_pkg *rx_packets[TB_CTL_RX_PKG_COUNT]; |
46 | struct mutex request_queue_lock; |
47 | struct list_head request_queue; |
48 | bool running; |
49 | |
50 | int timeout_msec; |
51 | event_cb callback; |
52 | void *callback_data; |
53 | |
54 | int index; |
55 | }; |
56 | |
57 | |
58 | #define tb_ctl_WARN(ctl, format, arg...) \ |
59 | dev_WARN(&(ctl)->nhi->pdev->dev, format, ## arg) |
60 | |
61 | #define tb_ctl_err(ctl, format, arg...) \ |
62 | dev_err(&(ctl)->nhi->pdev->dev, format, ## arg) |
63 | |
64 | #define tb_ctl_warn(ctl, format, arg...) \ |
65 | dev_warn(&(ctl)->nhi->pdev->dev, format, ## arg) |
66 | |
67 | #define tb_ctl_info(ctl, format, arg...) \ |
68 | dev_info(&(ctl)->nhi->pdev->dev, format, ## arg) |
69 | |
70 | #define tb_ctl_dbg(ctl, format, arg...) \ |
71 | dev_dbg(&(ctl)->nhi->pdev->dev, format, ## arg) |
72 | |
73 | static DECLARE_WAIT_QUEUE_HEAD(tb_cfg_request_cancel_queue); |
74 | /* Serializes access to request kref_get/put */ |
75 | static DEFINE_MUTEX(tb_cfg_request_lock); |
76 | |
77 | /** |
78 | * tb_cfg_request_alloc() - Allocates a new config request |
79 | * |
80 | * This is refcounted object so when you are done with this, call |
81 | * tb_cfg_request_put() to it. |
82 | */ |
83 | struct tb_cfg_request *tb_cfg_request_alloc(void) |
84 | { |
85 | struct tb_cfg_request *req; |
86 | |
87 | req = kzalloc(size: sizeof(*req), GFP_KERNEL); |
88 | if (!req) |
89 | return NULL; |
90 | |
91 | kref_init(kref: &req->kref); |
92 | |
93 | return req; |
94 | } |
95 | |
96 | /** |
97 | * tb_cfg_request_get() - Increase refcount of a request |
98 | * @req: Request whose refcount is increased |
99 | */ |
100 | void tb_cfg_request_get(struct tb_cfg_request *req) |
101 | { |
102 | mutex_lock(&tb_cfg_request_lock); |
103 | kref_get(kref: &req->kref); |
104 | mutex_unlock(lock: &tb_cfg_request_lock); |
105 | } |
106 | |
107 | static void tb_cfg_request_destroy(struct kref *kref) |
108 | { |
109 | struct tb_cfg_request *req = container_of(kref, typeof(*req), kref); |
110 | |
111 | kfree(objp: req); |
112 | } |
113 | |
114 | /** |
115 | * tb_cfg_request_put() - Decrease refcount and possibly release the request |
116 | * @req: Request whose refcount is decreased |
117 | * |
118 | * Call this function when you are done with the request. When refcount |
119 | * goes to %0 the object is released. |
120 | */ |
121 | void tb_cfg_request_put(struct tb_cfg_request *req) |
122 | { |
123 | mutex_lock(&tb_cfg_request_lock); |
124 | kref_put(kref: &req->kref, release: tb_cfg_request_destroy); |
125 | mutex_unlock(lock: &tb_cfg_request_lock); |
126 | } |
127 | |
128 | static int tb_cfg_request_enqueue(struct tb_ctl *ctl, |
129 | struct tb_cfg_request *req) |
130 | { |
131 | WARN_ON(test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags)); |
132 | WARN_ON(req->ctl); |
133 | |
134 | mutex_lock(&ctl->request_queue_lock); |
135 | if (!ctl->running) { |
136 | mutex_unlock(lock: &ctl->request_queue_lock); |
137 | return -ENOTCONN; |
138 | } |
139 | req->ctl = ctl; |
140 | list_add_tail(new: &req->list, head: &ctl->request_queue); |
141 | set_bit(TB_CFG_REQUEST_ACTIVE, addr: &req->flags); |
142 | mutex_unlock(lock: &ctl->request_queue_lock); |
143 | return 0; |
144 | } |
145 | |
146 | static void tb_cfg_request_dequeue(struct tb_cfg_request *req) |
147 | { |
148 | struct tb_ctl *ctl = req->ctl; |
149 | |
150 | mutex_lock(&ctl->request_queue_lock); |
151 | list_del(entry: &req->list); |
152 | clear_bit(TB_CFG_REQUEST_ACTIVE, addr: &req->flags); |
153 | if (test_bit(TB_CFG_REQUEST_CANCELED, &req->flags)) |
154 | wake_up(&tb_cfg_request_cancel_queue); |
155 | mutex_unlock(lock: &ctl->request_queue_lock); |
156 | } |
157 | |
158 | static bool tb_cfg_request_is_active(struct tb_cfg_request *req) |
159 | { |
160 | return test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags); |
161 | } |
162 | |
163 | static struct tb_cfg_request * |
164 | tb_cfg_request_find(struct tb_ctl *ctl, struct ctl_pkg *pkg) |
165 | { |
166 | struct tb_cfg_request *req = NULL, *iter; |
167 | |
168 | mutex_lock(&pkg->ctl->request_queue_lock); |
169 | list_for_each_entry(iter, &pkg->ctl->request_queue, list) { |
170 | tb_cfg_request_get(req: iter); |
171 | if (iter->match(iter, pkg)) { |
172 | req = iter; |
173 | break; |
174 | } |
175 | tb_cfg_request_put(req: iter); |
176 | } |
177 | mutex_unlock(lock: &pkg->ctl->request_queue_lock); |
178 | |
179 | return req; |
180 | } |
181 | |
182 | /* utility functions */ |
183 | |
184 | |
185 | static int (const struct ctl_pkg *pkg, u32 len, |
186 | enum tb_cfg_pkg_type type, u64 route) |
187 | { |
188 | struct tb_cfg_header * = pkg->buffer; |
189 | |
190 | /* check frame, TODO: frame flags */ |
191 | if (WARN(len != pkg->frame.size, |
192 | "wrong framesize (expected %#x, got %#x)\n" , |
193 | len, pkg->frame.size)) |
194 | return -EIO; |
195 | if (WARN(type != pkg->frame.eof, "wrong eof (expected %#x, got %#x)\n" , |
196 | type, pkg->frame.eof)) |
197 | return -EIO; |
198 | if (WARN(pkg->frame.sof, "wrong sof (expected 0x0, got %#x)\n" , |
199 | pkg->frame.sof)) |
200 | return -EIO; |
201 | |
202 | /* check header */ |
203 | if (WARN(header->unknown != 1 << 9, |
204 | "header->unknown is %#x\n" , header->unknown)) |
205 | return -EIO; |
206 | if (WARN(route != tb_cfg_get_route(header), |
207 | "wrong route (expected %llx, got %llx)" , |
208 | route, tb_cfg_get_route(header))) |
209 | return -EIO; |
210 | return 0; |
211 | } |
212 | |
213 | static int check_config_address(struct tb_cfg_address addr, |
214 | enum tb_cfg_space space, u32 offset, |
215 | u32 length) |
216 | { |
217 | if (WARN(addr.zero, "addr.zero is %#x\n" , addr.zero)) |
218 | return -EIO; |
219 | if (WARN(space != addr.space, "wrong space (expected %x, got %x\n)" , |
220 | space, addr.space)) |
221 | return -EIO; |
222 | if (WARN(offset != addr.offset, "wrong offset (expected %x, got %x\n)" , |
223 | offset, addr.offset)) |
224 | return -EIO; |
225 | if (WARN(length != addr.length, "wrong space (expected %x, got %x\n)" , |
226 | length, addr.length)) |
227 | return -EIO; |
228 | /* |
229 | * We cannot check addr->port as it is set to the upstream port of the |
230 | * sender. |
231 | */ |
232 | return 0; |
233 | } |
234 | |
235 | static struct tb_cfg_result decode_error(const struct ctl_pkg *response) |
236 | { |
237 | struct cfg_error_pkg *pkg = response->buffer; |
238 | struct tb_cfg_result res = { 0 }; |
239 | res.response_route = tb_cfg_get_route(header: &pkg->header); |
240 | res.response_port = 0; |
241 | res.err = check_header(pkg: response, len: sizeof(*pkg), type: TB_CFG_PKG_ERROR, |
242 | route: tb_cfg_get_route(header: &pkg->header)); |
243 | if (res.err) |
244 | return res; |
245 | |
246 | res.err = 1; |
247 | res.tb_error = pkg->error; |
248 | res.response_port = pkg->port; |
249 | return res; |
250 | |
251 | } |
252 | |
253 | static struct tb_cfg_result (const struct ctl_pkg *pkg, u32 len, |
254 | enum tb_cfg_pkg_type type, u64 route) |
255 | { |
256 | struct tb_cfg_header * = pkg->buffer; |
257 | struct tb_cfg_result res = { 0 }; |
258 | |
259 | if (pkg->frame.eof == TB_CFG_PKG_ERROR) |
260 | return decode_error(response: pkg); |
261 | |
262 | res.response_port = 0; /* will be updated later for cfg_read/write */ |
263 | res.response_route = tb_cfg_get_route(header); |
264 | res.err = check_header(pkg, len, type, route); |
265 | return res; |
266 | } |
267 | |
268 | static void tb_cfg_print_error(struct tb_ctl *ctl, |
269 | const struct tb_cfg_result *res) |
270 | { |
271 | WARN_ON(res->err != 1); |
272 | switch (res->tb_error) { |
273 | case TB_CFG_ERROR_PORT_NOT_CONNECTED: |
274 | /* Port is not connected. This can happen during surprise |
275 | * removal. Do not warn. */ |
276 | return; |
277 | case TB_CFG_ERROR_INVALID_CONFIG_SPACE: |
278 | /* |
279 | * Invalid cfg_space/offset/length combination in |
280 | * cfg_read/cfg_write. |
281 | */ |
282 | tb_ctl_dbg(ctl, "%llx:%x: invalid config space or offset\n" , |
283 | res->response_route, res->response_port); |
284 | return; |
285 | case TB_CFG_ERROR_NO_SUCH_PORT: |
286 | /* |
287 | * - The route contains a non-existent port. |
288 | * - The route contains a non-PHY port (e.g. PCIe). |
289 | * - The port in cfg_read/cfg_write does not exist. |
290 | */ |
291 | tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Invalid port\n" , |
292 | res->response_route, res->response_port); |
293 | return; |
294 | case TB_CFG_ERROR_LOOP: |
295 | tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Route contains a loop\n" , |
296 | res->response_route, res->response_port); |
297 | return; |
298 | case TB_CFG_ERROR_LOCK: |
299 | tb_ctl_warn(ctl, "%llx:%x: downstream port is locked\n" , |
300 | res->response_route, res->response_port); |
301 | return; |
302 | default: |
303 | /* 5,6,7,9 and 11 are also valid error codes */ |
304 | tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Unknown error\n" , |
305 | res->response_route, res->response_port); |
306 | return; |
307 | } |
308 | } |
309 | |
310 | static __be32 tb_crc(const void *data, size_t len) |
311 | { |
312 | return cpu_to_be32(~__crc32c_le(~0, data, len)); |
313 | } |
314 | |
315 | static void tb_ctl_pkg_free(struct ctl_pkg *pkg) |
316 | { |
317 | if (pkg) { |
318 | dma_pool_free(pool: pkg->ctl->frame_pool, |
319 | vaddr: pkg->buffer, addr: pkg->frame.buffer_phy); |
320 | kfree(objp: pkg); |
321 | } |
322 | } |
323 | |
324 | static struct ctl_pkg *tb_ctl_pkg_alloc(struct tb_ctl *ctl) |
325 | { |
326 | struct ctl_pkg *pkg = kzalloc(size: sizeof(*pkg), GFP_KERNEL); |
327 | if (!pkg) |
328 | return NULL; |
329 | pkg->ctl = ctl; |
330 | pkg->buffer = dma_pool_alloc(pool: ctl->frame_pool, GFP_KERNEL, |
331 | handle: &pkg->frame.buffer_phy); |
332 | if (!pkg->buffer) { |
333 | kfree(objp: pkg); |
334 | return NULL; |
335 | } |
336 | return pkg; |
337 | } |
338 | |
339 | |
340 | /* RX/TX handling */ |
341 | |
342 | static void tb_ctl_tx_callback(struct tb_ring *ring, struct ring_frame *frame, |
343 | bool canceled) |
344 | { |
345 | struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame); |
346 | tb_ctl_pkg_free(pkg); |
347 | } |
348 | |
349 | /* |
350 | * tb_cfg_tx() - transmit a packet on the control channel |
351 | * |
352 | * len must be a multiple of four. |
353 | * |
354 | * Return: Returns 0 on success or an error code on failure. |
355 | */ |
356 | static int tb_ctl_tx(struct tb_ctl *ctl, const void *data, size_t len, |
357 | enum tb_cfg_pkg_type type) |
358 | { |
359 | int res; |
360 | struct ctl_pkg *pkg; |
361 | if (len % 4 != 0) { /* required for le->be conversion */ |
362 | tb_ctl_WARN(ctl, "TX: invalid size: %zu\n" , len); |
363 | return -EINVAL; |
364 | } |
365 | if (len > TB_FRAME_SIZE - 4) { /* checksum is 4 bytes */ |
366 | tb_ctl_WARN(ctl, "TX: packet too large: %zu/%d\n" , |
367 | len, TB_FRAME_SIZE - 4); |
368 | return -EINVAL; |
369 | } |
370 | pkg = tb_ctl_pkg_alloc(ctl); |
371 | if (!pkg) |
372 | return -ENOMEM; |
373 | pkg->frame.callback = tb_ctl_tx_callback; |
374 | pkg->frame.size = len + 4; |
375 | pkg->frame.sof = type; |
376 | pkg->frame.eof = type; |
377 | |
378 | trace_tb_tx(index: ctl->index, type, data, size: len); |
379 | |
380 | cpu_to_be32_array(dst: pkg->buffer, src: data, len: len / 4); |
381 | *(__be32 *) (pkg->buffer + len) = tb_crc(data: pkg->buffer, len); |
382 | |
383 | res = tb_ring_tx(ring: ctl->tx, frame: &pkg->frame); |
384 | if (res) /* ring is stopped */ |
385 | tb_ctl_pkg_free(pkg); |
386 | return res; |
387 | } |
388 | |
389 | /* |
390 | * tb_ctl_handle_event() - acknowledge a plug event, invoke ctl->callback |
391 | */ |
392 | static bool tb_ctl_handle_event(struct tb_ctl *ctl, enum tb_cfg_pkg_type type, |
393 | struct ctl_pkg *pkg, size_t size) |
394 | { |
395 | trace_tb_event(index: ctl->index, type, data: pkg->buffer, size); |
396 | return ctl->callback(ctl->callback_data, type, pkg->buffer, size); |
397 | } |
398 | |
399 | static void tb_ctl_rx_submit(struct ctl_pkg *pkg) |
400 | { |
401 | tb_ring_rx(ring: pkg->ctl->rx, frame: &pkg->frame); /* |
402 | * We ignore failures during stop. |
403 | * All rx packets are referenced |
404 | * from ctl->rx_packets, so we do |
405 | * not loose them. |
406 | */ |
407 | } |
408 | |
409 | static int tb_async_error(const struct ctl_pkg *pkg) |
410 | { |
411 | const struct cfg_error_pkg *error = pkg->buffer; |
412 | |
413 | if (pkg->frame.eof != TB_CFG_PKG_ERROR) |
414 | return false; |
415 | |
416 | switch (error->error) { |
417 | case TB_CFG_ERROR_LINK_ERROR: |
418 | case TB_CFG_ERROR_HEC_ERROR_DETECTED: |
419 | case TB_CFG_ERROR_FLOW_CONTROL_ERROR: |
420 | case TB_CFG_ERROR_DP_BW: |
421 | case TB_CFG_ERROR_ROP_CMPLT: |
422 | case TB_CFG_ERROR_POP_CMPLT: |
423 | case TB_CFG_ERROR_PCIE_WAKE: |
424 | case TB_CFG_ERROR_DP_CON_CHANGE: |
425 | case TB_CFG_ERROR_DPTX_DISCOVERY: |
426 | case TB_CFG_ERROR_LINK_RECOVERY: |
427 | case TB_CFG_ERROR_ASYM_LINK: |
428 | return true; |
429 | |
430 | default: |
431 | return false; |
432 | } |
433 | } |
434 | |
435 | static void tb_ctl_rx_callback(struct tb_ring *ring, struct ring_frame *frame, |
436 | bool canceled) |
437 | { |
438 | struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame); |
439 | struct tb_cfg_request *req; |
440 | __be32 crc32; |
441 | |
442 | if (canceled) |
443 | return; /* |
444 | * ring is stopped, packet is referenced from |
445 | * ctl->rx_packets. |
446 | */ |
447 | |
448 | if (frame->size < 4 || frame->size % 4 != 0) { |
449 | tb_ctl_err(pkg->ctl, "RX: invalid size %#x, dropping packet\n" , |
450 | frame->size); |
451 | goto rx; |
452 | } |
453 | |
454 | frame->size -= 4; /* remove checksum */ |
455 | crc32 = tb_crc(data: pkg->buffer, len: frame->size); |
456 | be32_to_cpu_array(dst: pkg->buffer, src: pkg->buffer, len: frame->size / 4); |
457 | |
458 | switch (frame->eof) { |
459 | case TB_CFG_PKG_READ: |
460 | case TB_CFG_PKG_WRITE: |
461 | case TB_CFG_PKG_ERROR: |
462 | case TB_CFG_PKG_OVERRIDE: |
463 | case TB_CFG_PKG_RESET: |
464 | if (*(__be32 *)(pkg->buffer + frame->size) != crc32) { |
465 | tb_ctl_err(pkg->ctl, |
466 | "RX: checksum mismatch, dropping packet\n" ); |
467 | goto rx; |
468 | } |
469 | if (tb_async_error(pkg)) { |
470 | tb_ctl_handle_event(ctl: pkg->ctl, type: frame->eof, |
471 | pkg, size: frame->size); |
472 | goto rx; |
473 | } |
474 | break; |
475 | |
476 | case TB_CFG_PKG_EVENT: |
477 | case TB_CFG_PKG_XDOMAIN_RESP: |
478 | case TB_CFG_PKG_XDOMAIN_REQ: |
479 | if (*(__be32 *)(pkg->buffer + frame->size) != crc32) { |
480 | tb_ctl_err(pkg->ctl, |
481 | "RX: checksum mismatch, dropping packet\n" ); |
482 | goto rx; |
483 | } |
484 | fallthrough; |
485 | case TB_CFG_PKG_ICM_EVENT: |
486 | if (tb_ctl_handle_event(ctl: pkg->ctl, type: frame->eof, pkg, size: frame->size)) |
487 | goto rx; |
488 | break; |
489 | |
490 | default: |
491 | break; |
492 | } |
493 | |
494 | /* |
495 | * The received packet will be processed only if there is an |
496 | * active request and that the packet is what is expected. This |
497 | * prevents packets such as replies coming after timeout has |
498 | * triggered from messing with the active requests. |
499 | */ |
500 | req = tb_cfg_request_find(ctl: pkg->ctl, pkg); |
501 | |
502 | trace_tb_rx(index: pkg->ctl->index, type: frame->eof, data: pkg->buffer, size: frame->size, dropped: !req); |
503 | |
504 | if (req) { |
505 | if (req->copy(req, pkg)) |
506 | schedule_work(work: &req->work); |
507 | tb_cfg_request_put(req); |
508 | } |
509 | |
510 | rx: |
511 | tb_ctl_rx_submit(pkg); |
512 | } |
513 | |
514 | static void tb_cfg_request_work(struct work_struct *work) |
515 | { |
516 | struct tb_cfg_request *req = container_of(work, typeof(*req), work); |
517 | |
518 | if (!test_bit(TB_CFG_REQUEST_CANCELED, &req->flags)) |
519 | req->callback(req->callback_data); |
520 | |
521 | tb_cfg_request_dequeue(req); |
522 | tb_cfg_request_put(req); |
523 | } |
524 | |
525 | /** |
526 | * tb_cfg_request() - Start control request not waiting for it to complete |
527 | * @ctl: Control channel to use |
528 | * @req: Request to start |
529 | * @callback: Callback called when the request is completed |
530 | * @callback_data: Data to be passed to @callback |
531 | * |
532 | * This queues @req on the given control channel without waiting for it |
533 | * to complete. When the request completes @callback is called. |
534 | */ |
535 | int tb_cfg_request(struct tb_ctl *ctl, struct tb_cfg_request *req, |
536 | void (*callback)(void *), void *callback_data) |
537 | { |
538 | int ret; |
539 | |
540 | req->flags = 0; |
541 | req->callback = callback; |
542 | req->callback_data = callback_data; |
543 | INIT_WORK(&req->work, tb_cfg_request_work); |
544 | INIT_LIST_HEAD(list: &req->list); |
545 | |
546 | tb_cfg_request_get(req); |
547 | ret = tb_cfg_request_enqueue(ctl, req); |
548 | if (ret) |
549 | goto err_put; |
550 | |
551 | ret = tb_ctl_tx(ctl, data: req->request, len: req->request_size, |
552 | type: req->request_type); |
553 | if (ret) |
554 | goto err_dequeue; |
555 | |
556 | if (!req->response) |
557 | schedule_work(work: &req->work); |
558 | |
559 | return 0; |
560 | |
561 | err_dequeue: |
562 | tb_cfg_request_dequeue(req); |
563 | err_put: |
564 | tb_cfg_request_put(req); |
565 | |
566 | return ret; |
567 | } |
568 | |
569 | /** |
570 | * tb_cfg_request_cancel() - Cancel a control request |
571 | * @req: Request to cancel |
572 | * @err: Error to assign to the request |
573 | * |
574 | * This function can be used to cancel ongoing request. It will wait |
575 | * until the request is not active anymore. |
576 | */ |
577 | void tb_cfg_request_cancel(struct tb_cfg_request *req, int err) |
578 | { |
579 | set_bit(TB_CFG_REQUEST_CANCELED, addr: &req->flags); |
580 | schedule_work(work: &req->work); |
581 | wait_event(tb_cfg_request_cancel_queue, !tb_cfg_request_is_active(req)); |
582 | req->result.err = err; |
583 | } |
584 | |
585 | static void tb_cfg_request_complete(void *data) |
586 | { |
587 | complete(data); |
588 | } |
589 | |
590 | /** |
591 | * tb_cfg_request_sync() - Start control request and wait until it completes |
592 | * @ctl: Control channel to use |
593 | * @req: Request to start |
594 | * @timeout_msec: Timeout how long to wait @req to complete |
595 | * |
596 | * Starts a control request and waits until it completes. If timeout |
597 | * triggers the request is canceled before function returns. Note the |
598 | * caller needs to make sure only one message for given switch is active |
599 | * at a time. |
600 | */ |
601 | struct tb_cfg_result tb_cfg_request_sync(struct tb_ctl *ctl, |
602 | struct tb_cfg_request *req, |
603 | int timeout_msec) |
604 | { |
605 | unsigned long timeout = msecs_to_jiffies(m: timeout_msec); |
606 | struct tb_cfg_result res = { 0 }; |
607 | DECLARE_COMPLETION_ONSTACK(done); |
608 | int ret; |
609 | |
610 | ret = tb_cfg_request(ctl, req, callback: tb_cfg_request_complete, callback_data: &done); |
611 | if (ret) { |
612 | res.err = ret; |
613 | return res; |
614 | } |
615 | |
616 | if (!wait_for_completion_timeout(x: &done, timeout)) |
617 | tb_cfg_request_cancel(req, err: -ETIMEDOUT); |
618 | |
619 | flush_work(work: &req->work); |
620 | |
621 | return req->result; |
622 | } |
623 | |
624 | /* public interface, alloc/start/stop/free */ |
625 | |
626 | /** |
627 | * tb_ctl_alloc() - allocate a control channel |
628 | * @nhi: Pointer to NHI |
629 | * @index: Domain number |
630 | * @timeout_msec: Default timeout used with non-raw control messages |
631 | * @cb: Callback called for plug events |
632 | * @cb_data: Data passed to @cb |
633 | * |
634 | * cb will be invoked once for every hot plug event. |
635 | * |
636 | * Return: Returns a pointer on success or NULL on failure. |
637 | */ |
638 | struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, int index, int timeout_msec, |
639 | event_cb cb, void *cb_data) |
640 | { |
641 | int i; |
642 | struct tb_ctl *ctl = kzalloc(size: sizeof(*ctl), GFP_KERNEL); |
643 | if (!ctl) |
644 | return NULL; |
645 | |
646 | ctl->nhi = nhi; |
647 | ctl->index = index; |
648 | ctl->timeout_msec = timeout_msec; |
649 | ctl->callback = cb; |
650 | ctl->callback_data = cb_data; |
651 | |
652 | mutex_init(&ctl->request_queue_lock); |
653 | INIT_LIST_HEAD(list: &ctl->request_queue); |
654 | ctl->frame_pool = dma_pool_create(name: "thunderbolt_ctl" , dev: &nhi->pdev->dev, |
655 | TB_FRAME_SIZE, align: 4, allocation: 0); |
656 | if (!ctl->frame_pool) |
657 | goto err; |
658 | |
659 | ctl->tx = tb_ring_alloc_tx(nhi, hop: 0, size: 10, RING_FLAG_NO_SUSPEND); |
660 | if (!ctl->tx) |
661 | goto err; |
662 | |
663 | ctl->rx = tb_ring_alloc_rx(nhi, hop: 0, size: 10, RING_FLAG_NO_SUSPEND, e2e_tx_hop: 0, sof_mask: 0xffff, |
664 | eof_mask: 0xffff, NULL, NULL); |
665 | if (!ctl->rx) |
666 | goto err; |
667 | |
668 | for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) { |
669 | ctl->rx_packets[i] = tb_ctl_pkg_alloc(ctl); |
670 | if (!ctl->rx_packets[i]) |
671 | goto err; |
672 | ctl->rx_packets[i]->frame.callback = tb_ctl_rx_callback; |
673 | } |
674 | |
675 | tb_ctl_dbg(ctl, "control channel created\n" ); |
676 | return ctl; |
677 | err: |
678 | tb_ctl_free(ctl); |
679 | return NULL; |
680 | } |
681 | |
682 | /** |
683 | * tb_ctl_free() - free a control channel |
684 | * @ctl: Control channel to free |
685 | * |
686 | * Must be called after tb_ctl_stop. |
687 | * |
688 | * Must NOT be called from ctl->callback. |
689 | */ |
690 | void tb_ctl_free(struct tb_ctl *ctl) |
691 | { |
692 | int i; |
693 | |
694 | if (!ctl) |
695 | return; |
696 | |
697 | if (ctl->rx) |
698 | tb_ring_free(ring: ctl->rx); |
699 | if (ctl->tx) |
700 | tb_ring_free(ring: ctl->tx); |
701 | |
702 | /* free RX packets */ |
703 | for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) |
704 | tb_ctl_pkg_free(pkg: ctl->rx_packets[i]); |
705 | |
706 | |
707 | dma_pool_destroy(pool: ctl->frame_pool); |
708 | kfree(objp: ctl); |
709 | } |
710 | |
711 | /** |
712 | * tb_ctl_start() - start/resume the control channel |
713 | * @ctl: Control channel to start |
714 | */ |
715 | void tb_ctl_start(struct tb_ctl *ctl) |
716 | { |
717 | int i; |
718 | tb_ctl_dbg(ctl, "control channel starting...\n" ); |
719 | tb_ring_start(ring: ctl->tx); /* is used to ack hotplug packets, start first */ |
720 | tb_ring_start(ring: ctl->rx); |
721 | for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) |
722 | tb_ctl_rx_submit(pkg: ctl->rx_packets[i]); |
723 | |
724 | ctl->running = true; |
725 | } |
726 | |
727 | /** |
728 | * tb_ctl_stop() - pause the control channel |
729 | * @ctl: Control channel to stop |
730 | * |
731 | * All invocations of ctl->callback will have finished after this method |
732 | * returns. |
733 | * |
734 | * Must NOT be called from ctl->callback. |
735 | */ |
736 | void tb_ctl_stop(struct tb_ctl *ctl) |
737 | { |
738 | mutex_lock(&ctl->request_queue_lock); |
739 | ctl->running = false; |
740 | mutex_unlock(lock: &ctl->request_queue_lock); |
741 | |
742 | tb_ring_stop(ring: ctl->rx); |
743 | tb_ring_stop(ring: ctl->tx); |
744 | |
745 | if (!list_empty(head: &ctl->request_queue)) |
746 | tb_ctl_WARN(ctl, "dangling request in request_queue\n" ); |
747 | INIT_LIST_HEAD(list: &ctl->request_queue); |
748 | tb_ctl_dbg(ctl, "control channel stopped\n" ); |
749 | } |
750 | |
751 | /* public interface, commands */ |
752 | |
753 | /** |
754 | * tb_cfg_ack_notification() - Ack notification |
755 | * @ctl: Control channel to use |
756 | * @route: Router that originated the event |
757 | * @error: Pointer to the notification package |
758 | * |
759 | * Call this as response for non-plug notification to ack it. Returns |
760 | * %0 on success or an error code on failure. |
761 | */ |
762 | int tb_cfg_ack_notification(struct tb_ctl *ctl, u64 route, |
763 | const struct cfg_error_pkg *error) |
764 | { |
765 | struct cfg_ack_pkg pkg = { |
766 | .header = tb_cfg_make_header(route), |
767 | }; |
768 | const char *name; |
769 | |
770 | switch (error->error) { |
771 | case TB_CFG_ERROR_LINK_ERROR: |
772 | name = "link error" ; |
773 | break; |
774 | case TB_CFG_ERROR_HEC_ERROR_DETECTED: |
775 | name = "HEC error" ; |
776 | break; |
777 | case TB_CFG_ERROR_FLOW_CONTROL_ERROR: |
778 | name = "flow control error" ; |
779 | break; |
780 | case TB_CFG_ERROR_DP_BW: |
781 | name = "DP_BW" ; |
782 | break; |
783 | case TB_CFG_ERROR_ROP_CMPLT: |
784 | name = "router operation completion" ; |
785 | break; |
786 | case TB_CFG_ERROR_POP_CMPLT: |
787 | name = "port operation completion" ; |
788 | break; |
789 | case TB_CFG_ERROR_PCIE_WAKE: |
790 | name = "PCIe wake" ; |
791 | break; |
792 | case TB_CFG_ERROR_DP_CON_CHANGE: |
793 | name = "DP connector change" ; |
794 | break; |
795 | case TB_CFG_ERROR_DPTX_DISCOVERY: |
796 | name = "DPTX discovery" ; |
797 | break; |
798 | case TB_CFG_ERROR_LINK_RECOVERY: |
799 | name = "link recovery" ; |
800 | break; |
801 | case TB_CFG_ERROR_ASYM_LINK: |
802 | name = "asymmetric link" ; |
803 | break; |
804 | default: |
805 | name = "unknown" ; |
806 | break; |
807 | } |
808 | |
809 | tb_ctl_dbg(ctl, "acking %s (%#x) notification on %llx\n" , name, |
810 | error->error, route); |
811 | |
812 | return tb_ctl_tx(ctl, data: &pkg, len: sizeof(pkg), type: TB_CFG_PKG_NOTIFY_ACK); |
813 | } |
814 | |
815 | /** |
816 | * tb_cfg_ack_plug() - Ack hot plug/unplug event |
817 | * @ctl: Control channel to use |
818 | * @route: Router that originated the event |
819 | * @port: Port where the hot plug/unplug happened |
820 | * @unplug: Ack hot plug or unplug |
821 | * |
822 | * Call this as response for hot plug/unplug event to ack it. |
823 | * Returns %0 on success or an error code on failure. |
824 | */ |
825 | int tb_cfg_ack_plug(struct tb_ctl *ctl, u64 route, u32 port, bool unplug) |
826 | { |
827 | struct cfg_error_pkg pkg = { |
828 | .header = tb_cfg_make_header(route), |
829 | .port = port, |
830 | .error = TB_CFG_ERROR_ACK_PLUG_EVENT, |
831 | .pg = unplug ? TB_CFG_ERROR_PG_HOT_UNPLUG |
832 | : TB_CFG_ERROR_PG_HOT_PLUG, |
833 | }; |
834 | tb_ctl_dbg(ctl, "acking hot %splug event on %llx:%u\n" , |
835 | unplug ? "un" : "" , route, port); |
836 | return tb_ctl_tx(ctl, data: &pkg, len: sizeof(pkg), type: TB_CFG_PKG_ERROR); |
837 | } |
838 | |
839 | static bool tb_cfg_match(const struct tb_cfg_request *req, |
840 | const struct ctl_pkg *pkg) |
841 | { |
842 | u64 route = tb_cfg_get_route(header: pkg->buffer) & ~BIT_ULL(63); |
843 | |
844 | if (pkg->frame.eof == TB_CFG_PKG_ERROR) |
845 | return true; |
846 | |
847 | if (pkg->frame.eof != req->response_type) |
848 | return false; |
849 | if (route != tb_cfg_get_route(header: req->request)) |
850 | return false; |
851 | if (pkg->frame.size != req->response_size) |
852 | return false; |
853 | |
854 | if (pkg->frame.eof == TB_CFG_PKG_READ || |
855 | pkg->frame.eof == TB_CFG_PKG_WRITE) { |
856 | const struct cfg_read_pkg *req_hdr = req->request; |
857 | const struct cfg_read_pkg *res_hdr = pkg->buffer; |
858 | |
859 | if (req_hdr->addr.seq != res_hdr->addr.seq) |
860 | return false; |
861 | } |
862 | |
863 | return true; |
864 | } |
865 | |
866 | static bool tb_cfg_copy(struct tb_cfg_request *req, const struct ctl_pkg *pkg) |
867 | { |
868 | struct tb_cfg_result res; |
869 | |
870 | /* Now make sure it is in expected format */ |
871 | res = parse_header(pkg, len: req->response_size, type: req->response_type, |
872 | route: tb_cfg_get_route(header: req->request)); |
873 | if (!res.err) |
874 | memcpy(req->response, pkg->buffer, req->response_size); |
875 | |
876 | req->result = res; |
877 | |
878 | /* Always complete when first response is received */ |
879 | return true; |
880 | } |
881 | |
882 | /** |
883 | * tb_cfg_reset() - send a reset packet and wait for a response |
884 | * @ctl: Control channel pointer |
885 | * @route: Router string for the router to send reset |
886 | * |
887 | * If the switch at route is incorrectly configured then we will not receive a |
888 | * reply (even though the switch will reset). The caller should check for |
889 | * -ETIMEDOUT and attempt to reconfigure the switch. |
890 | */ |
891 | struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route) |
892 | { |
893 | struct cfg_reset_pkg request = { .header = tb_cfg_make_header(route) }; |
894 | struct tb_cfg_result res = { 0 }; |
895 | struct tb_cfg_header reply; |
896 | struct tb_cfg_request *req; |
897 | |
898 | req = tb_cfg_request_alloc(); |
899 | if (!req) { |
900 | res.err = -ENOMEM; |
901 | return res; |
902 | } |
903 | |
904 | req->match = tb_cfg_match; |
905 | req->copy = tb_cfg_copy; |
906 | req->request = &request; |
907 | req->request_size = sizeof(request); |
908 | req->request_type = TB_CFG_PKG_RESET; |
909 | req->response = &reply; |
910 | req->response_size = sizeof(reply); |
911 | req->response_type = TB_CFG_PKG_RESET; |
912 | |
913 | res = tb_cfg_request_sync(ctl, req, timeout_msec: ctl->timeout_msec); |
914 | |
915 | tb_cfg_request_put(req); |
916 | |
917 | return res; |
918 | } |
919 | |
920 | /** |
921 | * tb_cfg_read_raw() - read from config space into buffer |
922 | * @ctl: Pointer to the control channel |
923 | * @buffer: Buffer where the data is read |
924 | * @route: Route string of the router |
925 | * @port: Port number when reading from %TB_CFG_PORT, %0 otherwise |
926 | * @space: Config space selector |
927 | * @offset: Dword word offset of the register to start reading |
928 | * @length: Number of dwords to read |
929 | * @timeout_msec: Timeout in ms how long to wait for the response |
930 | * |
931 | * Reads from router config space without translating the possible error. |
932 | */ |
933 | struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer, |
934 | u64 route, u32 port, enum tb_cfg_space space, |
935 | u32 offset, u32 length, int timeout_msec) |
936 | { |
937 | struct tb_cfg_result res = { 0 }; |
938 | struct cfg_read_pkg request = { |
939 | .header = tb_cfg_make_header(route), |
940 | .addr = { |
941 | .port = port, |
942 | .space = space, |
943 | .offset = offset, |
944 | .length = length, |
945 | }, |
946 | }; |
947 | struct cfg_write_pkg reply; |
948 | int retries = 0; |
949 | |
950 | while (retries < TB_CTL_RETRIES) { |
951 | struct tb_cfg_request *req; |
952 | |
953 | req = tb_cfg_request_alloc(); |
954 | if (!req) { |
955 | res.err = -ENOMEM; |
956 | return res; |
957 | } |
958 | |
959 | request.addr.seq = retries++; |
960 | |
961 | req->match = tb_cfg_match; |
962 | req->copy = tb_cfg_copy; |
963 | req->request = &request; |
964 | req->request_size = sizeof(request); |
965 | req->request_type = TB_CFG_PKG_READ; |
966 | req->response = &reply; |
967 | req->response_size = 12 + 4 * length; |
968 | req->response_type = TB_CFG_PKG_READ; |
969 | |
970 | res = tb_cfg_request_sync(ctl, req, timeout_msec); |
971 | |
972 | tb_cfg_request_put(req); |
973 | |
974 | if (res.err != -ETIMEDOUT) |
975 | break; |
976 | |
977 | /* Wait a bit (arbitrary time) until we send a retry */ |
978 | usleep_range(min: 10, max: 100); |
979 | } |
980 | |
981 | if (res.err) |
982 | return res; |
983 | |
984 | res.response_port = reply.addr.port; |
985 | res.err = check_config_address(addr: reply.addr, space, offset, length); |
986 | if (!res.err) |
987 | memcpy(buffer, &reply.data, 4 * length); |
988 | return res; |
989 | } |
990 | |
991 | /** |
992 | * tb_cfg_write_raw() - write from buffer into config space |
993 | * @ctl: Pointer to the control channel |
994 | * @buffer: Data to write |
995 | * @route: Route string of the router |
996 | * @port: Port number when writing to %TB_CFG_PORT, %0 otherwise |
997 | * @space: Config space selector |
998 | * @offset: Dword word offset of the register to start writing |
999 | * @length: Number of dwords to write |
1000 | * @timeout_msec: Timeout in ms how long to wait for the response |
1001 | * |
1002 | * Writes to router config space without translating the possible error. |
1003 | */ |
1004 | struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, const void *buffer, |
1005 | u64 route, u32 port, enum tb_cfg_space space, |
1006 | u32 offset, u32 length, int timeout_msec) |
1007 | { |
1008 | struct tb_cfg_result res = { 0 }; |
1009 | struct cfg_write_pkg request = { |
1010 | .header = tb_cfg_make_header(route), |
1011 | .addr = { |
1012 | .port = port, |
1013 | .space = space, |
1014 | .offset = offset, |
1015 | .length = length, |
1016 | }, |
1017 | }; |
1018 | struct cfg_read_pkg reply; |
1019 | int retries = 0; |
1020 | |
1021 | memcpy(&request.data, buffer, length * 4); |
1022 | |
1023 | while (retries < TB_CTL_RETRIES) { |
1024 | struct tb_cfg_request *req; |
1025 | |
1026 | req = tb_cfg_request_alloc(); |
1027 | if (!req) { |
1028 | res.err = -ENOMEM; |
1029 | return res; |
1030 | } |
1031 | |
1032 | request.addr.seq = retries++; |
1033 | |
1034 | req->match = tb_cfg_match; |
1035 | req->copy = tb_cfg_copy; |
1036 | req->request = &request; |
1037 | req->request_size = 12 + 4 * length; |
1038 | req->request_type = TB_CFG_PKG_WRITE; |
1039 | req->response = &reply; |
1040 | req->response_size = sizeof(reply); |
1041 | req->response_type = TB_CFG_PKG_WRITE; |
1042 | |
1043 | res = tb_cfg_request_sync(ctl, req, timeout_msec); |
1044 | |
1045 | tb_cfg_request_put(req); |
1046 | |
1047 | if (res.err != -ETIMEDOUT) |
1048 | break; |
1049 | |
1050 | /* Wait a bit (arbitrary time) until we send a retry */ |
1051 | usleep_range(min: 10, max: 100); |
1052 | } |
1053 | |
1054 | if (res.err) |
1055 | return res; |
1056 | |
1057 | res.response_port = reply.addr.port; |
1058 | res.err = check_config_address(addr: reply.addr, space, offset, length); |
1059 | return res; |
1060 | } |
1061 | |
1062 | static int tb_cfg_get_error(struct tb_ctl *ctl, enum tb_cfg_space space, |
1063 | const struct tb_cfg_result *res) |
1064 | { |
1065 | /* |
1066 | * For unimplemented ports access to port config space may return |
1067 | * TB_CFG_ERROR_INVALID_CONFIG_SPACE (alternatively their type is |
1068 | * set to TB_TYPE_INACTIVE). In the former case return -ENODEV so |
1069 | * that the caller can mark the port as disabled. |
1070 | */ |
1071 | if (space == TB_CFG_PORT && |
1072 | res->tb_error == TB_CFG_ERROR_INVALID_CONFIG_SPACE) |
1073 | return -ENODEV; |
1074 | |
1075 | tb_cfg_print_error(ctl, res); |
1076 | |
1077 | if (res->tb_error == TB_CFG_ERROR_LOCK) |
1078 | return -EACCES; |
1079 | if (res->tb_error == TB_CFG_ERROR_PORT_NOT_CONNECTED) |
1080 | return -ENOTCONN; |
1081 | |
1082 | return -EIO; |
1083 | } |
1084 | |
1085 | int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port, |
1086 | enum tb_cfg_space space, u32 offset, u32 length) |
1087 | { |
1088 | struct tb_cfg_result res = tb_cfg_read_raw(ctl, buffer, route, port, |
1089 | space, offset, length, timeout_msec: ctl->timeout_msec); |
1090 | switch (res.err) { |
1091 | case 0: |
1092 | /* Success */ |
1093 | break; |
1094 | |
1095 | case 1: |
1096 | /* Thunderbolt error, tb_error holds the actual number */ |
1097 | return tb_cfg_get_error(ctl, space, res: &res); |
1098 | |
1099 | case -ETIMEDOUT: |
1100 | tb_ctl_warn(ctl, "%llx: timeout reading config space %u from %#x\n" , |
1101 | route, space, offset); |
1102 | break; |
1103 | |
1104 | default: |
1105 | WARN(1, "tb_cfg_read: %d\n" , res.err); |
1106 | break; |
1107 | } |
1108 | return res.err; |
1109 | } |
1110 | |
1111 | int tb_cfg_write(struct tb_ctl *ctl, const void *buffer, u64 route, u32 port, |
1112 | enum tb_cfg_space space, u32 offset, u32 length) |
1113 | { |
1114 | struct tb_cfg_result res = tb_cfg_write_raw(ctl, buffer, route, port, |
1115 | space, offset, length, timeout_msec: ctl->timeout_msec); |
1116 | switch (res.err) { |
1117 | case 0: |
1118 | /* Success */ |
1119 | break; |
1120 | |
1121 | case 1: |
1122 | /* Thunderbolt error, tb_error holds the actual number */ |
1123 | return tb_cfg_get_error(ctl, space, res: &res); |
1124 | |
1125 | case -ETIMEDOUT: |
1126 | tb_ctl_warn(ctl, "%llx: timeout writing config space %u to %#x\n" , |
1127 | route, space, offset); |
1128 | break; |
1129 | |
1130 | default: |
1131 | WARN(1, "tb_cfg_write: %d\n" , res.err); |
1132 | break; |
1133 | } |
1134 | return res.err; |
1135 | } |
1136 | |
1137 | /** |
1138 | * tb_cfg_get_upstream_port() - get upstream port number of switch at route |
1139 | * @ctl: Pointer to the control channel |
1140 | * @route: Route string of the router |
1141 | * |
1142 | * Reads the first dword from the switches TB_CFG_SWITCH config area and |
1143 | * returns the port number from which the reply originated. |
1144 | * |
1145 | * Return: Returns the upstream port number on success or an error code on |
1146 | * failure. |
1147 | */ |
1148 | int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route) |
1149 | { |
1150 | u32 dummy; |
1151 | struct tb_cfg_result res = tb_cfg_read_raw(ctl, buffer: &dummy, route, port: 0, |
1152 | space: TB_CFG_SWITCH, offset: 0, length: 1, |
1153 | timeout_msec: ctl->timeout_msec); |
1154 | if (res.err == 1) |
1155 | return -EIO; |
1156 | if (res.err) |
1157 | return res.err; |
1158 | return res.response_port; |
1159 | } |
1160 | |