Merge tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / thunderbolt / ctl.c
blobbac08b820015d5ba7cddb3dd8b7734986b9460fe
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Thunderbolt driver - control channel and configuration commands
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6 * Copyright (C) 2018, Intel Corporation
7 */
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>
16 #include "ctl.h"
19 #define TB_CTL_RX_PKG_COUNT 10
20 #define TB_CTL_RETRIES 4
22 /**
23 * struct tb_cfg - thunderbolt control channel
25 struct tb_ctl {
26 struct tb_nhi *nhi;
27 struct tb_ring *tx;
28 struct tb_ring *rx;
30 struct dma_pool *frame_pool;
31 struct ctl_pkg *rx_packets[TB_CTL_RX_PKG_COUNT];
32 struct mutex request_queue_lock;
33 struct list_head request_queue;
34 bool running;
36 event_cb callback;
37 void *callback_data;
41 #define tb_ctl_WARN(ctl, format, arg...) \
42 dev_WARN(&(ctl)->nhi->pdev->dev, format, ## arg)
44 #define tb_ctl_err(ctl, format, arg...) \
45 dev_err(&(ctl)->nhi->pdev->dev, format, ## arg)
47 #define tb_ctl_warn(ctl, format, arg...) \
48 dev_warn(&(ctl)->nhi->pdev->dev, format, ## arg)
50 #define tb_ctl_info(ctl, format, arg...) \
51 dev_info(&(ctl)->nhi->pdev->dev, format, ## arg)
53 #define tb_ctl_dbg(ctl, format, arg...) \
54 dev_dbg(&(ctl)->nhi->pdev->dev, format, ## arg)
56 static DECLARE_WAIT_QUEUE_HEAD(tb_cfg_request_cancel_queue);
57 /* Serializes access to request kref_get/put */
58 static DEFINE_MUTEX(tb_cfg_request_lock);
60 /**
61 * tb_cfg_request_alloc() - Allocates a new config request
63 * This is refcounted object so when you are done with this, call
64 * tb_cfg_request_put() to it.
66 struct tb_cfg_request *tb_cfg_request_alloc(void)
68 struct tb_cfg_request *req;
70 req = kzalloc(sizeof(*req), GFP_KERNEL);
71 if (!req)
72 return NULL;
74 kref_init(&req->kref);
76 return req;
79 /**
80 * tb_cfg_request_get() - Increase refcount of a request
81 * @req: Request whose refcount is increased
83 void tb_cfg_request_get(struct tb_cfg_request *req)
85 mutex_lock(&tb_cfg_request_lock);
86 kref_get(&req->kref);
87 mutex_unlock(&tb_cfg_request_lock);
90 static void tb_cfg_request_destroy(struct kref *kref)
92 struct tb_cfg_request *req = container_of(kref, typeof(*req), kref);
94 kfree(req);
97 /**
98 * tb_cfg_request_put() - Decrease refcount and possibly release the request
99 * @req: Request whose refcount is decreased
101 * Call this function when you are done with the request. When refcount
102 * goes to %0 the object is released.
104 void tb_cfg_request_put(struct tb_cfg_request *req)
106 mutex_lock(&tb_cfg_request_lock);
107 kref_put(&req->kref, tb_cfg_request_destroy);
108 mutex_unlock(&tb_cfg_request_lock);
111 static int tb_cfg_request_enqueue(struct tb_ctl *ctl,
112 struct tb_cfg_request *req)
114 WARN_ON(test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags));
115 WARN_ON(req->ctl);
117 mutex_lock(&ctl->request_queue_lock);
118 if (!ctl->running) {
119 mutex_unlock(&ctl->request_queue_lock);
120 return -ENOTCONN;
122 req->ctl = ctl;
123 list_add_tail(&req->list, &ctl->request_queue);
124 set_bit(TB_CFG_REQUEST_ACTIVE, &req->flags);
125 mutex_unlock(&ctl->request_queue_lock);
126 return 0;
129 static void tb_cfg_request_dequeue(struct tb_cfg_request *req)
131 struct tb_ctl *ctl = req->ctl;
133 mutex_lock(&ctl->request_queue_lock);
134 list_del(&req->list);
135 clear_bit(TB_CFG_REQUEST_ACTIVE, &req->flags);
136 if (test_bit(TB_CFG_REQUEST_CANCELED, &req->flags))
137 wake_up(&tb_cfg_request_cancel_queue);
138 mutex_unlock(&ctl->request_queue_lock);
141 static bool tb_cfg_request_is_active(struct tb_cfg_request *req)
143 return test_bit(TB_CFG_REQUEST_ACTIVE, &req->flags);
146 static struct tb_cfg_request *
147 tb_cfg_request_find(struct tb_ctl *ctl, struct ctl_pkg *pkg)
149 struct tb_cfg_request *req;
150 bool found = false;
152 mutex_lock(&pkg->ctl->request_queue_lock);
153 list_for_each_entry(req, &pkg->ctl->request_queue, list) {
154 tb_cfg_request_get(req);
155 if (req->match(req, pkg)) {
156 found = true;
157 break;
159 tb_cfg_request_put(req);
161 mutex_unlock(&pkg->ctl->request_queue_lock);
163 return found ? req : NULL;
166 /* utility functions */
169 static int check_header(const struct ctl_pkg *pkg, u32 len,
170 enum tb_cfg_pkg_type type, u64 route)
172 struct tb_cfg_header *header = pkg->buffer;
174 /* check frame, TODO: frame flags */
175 if (WARN(len != pkg->frame.size,
176 "wrong framesize (expected %#x, got %#x)\n",
177 len, pkg->frame.size))
178 return -EIO;
179 if (WARN(type != pkg->frame.eof, "wrong eof (expected %#x, got %#x)\n",
180 type, pkg->frame.eof))
181 return -EIO;
182 if (WARN(pkg->frame.sof, "wrong sof (expected 0x0, got %#x)\n",
183 pkg->frame.sof))
184 return -EIO;
186 /* check header */
187 if (WARN(header->unknown != 1 << 9,
188 "header->unknown is %#x\n", header->unknown))
189 return -EIO;
190 if (WARN(route != tb_cfg_get_route(header),
191 "wrong route (expected %llx, got %llx)",
192 route, tb_cfg_get_route(header)))
193 return -EIO;
194 return 0;
197 static int check_config_address(struct tb_cfg_address addr,
198 enum tb_cfg_space space, u32 offset,
199 u32 length)
201 if (WARN(addr.zero, "addr.zero is %#x\n", addr.zero))
202 return -EIO;
203 if (WARN(space != addr.space, "wrong space (expected %x, got %x\n)",
204 space, addr.space))
205 return -EIO;
206 if (WARN(offset != addr.offset, "wrong offset (expected %x, got %x\n)",
207 offset, addr.offset))
208 return -EIO;
209 if (WARN(length != addr.length, "wrong space (expected %x, got %x\n)",
210 length, addr.length))
211 return -EIO;
213 * We cannot check addr->port as it is set to the upstream port of the
214 * sender.
216 return 0;
219 static struct tb_cfg_result decode_error(const struct ctl_pkg *response)
221 struct cfg_error_pkg *pkg = response->buffer;
222 struct tb_ctl *ctl = response->ctl;
223 struct tb_cfg_result res = { 0 };
224 res.response_route = tb_cfg_get_route(&pkg->header);
225 res.response_port = 0;
226 res.err = check_header(response, sizeof(*pkg), TB_CFG_PKG_ERROR,
227 tb_cfg_get_route(&pkg->header));
228 if (res.err)
229 return res;
231 if (pkg->zero1)
232 tb_ctl_warn(ctl, "pkg->zero1 is %#x\n", pkg->zero1);
233 if (pkg->zero2)
234 tb_ctl_warn(ctl, "pkg->zero2 is %#x\n", pkg->zero2);
235 if (pkg->zero3)
236 tb_ctl_warn(ctl, "pkg->zero3 is %#x\n", pkg->zero3);
238 res.err = 1;
239 res.tb_error = pkg->error;
240 res.response_port = pkg->port;
241 return res;
245 static struct tb_cfg_result parse_header(const struct ctl_pkg *pkg, u32 len,
246 enum tb_cfg_pkg_type type, u64 route)
248 struct tb_cfg_header *header = pkg->buffer;
249 struct tb_cfg_result res = { 0 };
251 if (pkg->frame.eof == TB_CFG_PKG_ERROR)
252 return decode_error(pkg);
254 res.response_port = 0; /* will be updated later for cfg_read/write */
255 res.response_route = tb_cfg_get_route(header);
256 res.err = check_header(pkg, len, type, route);
257 return res;
260 static void tb_cfg_print_error(struct tb_ctl *ctl,
261 const struct tb_cfg_result *res)
263 WARN_ON(res->err != 1);
264 switch (res->tb_error) {
265 case TB_CFG_ERROR_PORT_NOT_CONNECTED:
266 /* Port is not connected. This can happen during surprise
267 * removal. Do not warn. */
268 return;
269 case TB_CFG_ERROR_INVALID_CONFIG_SPACE:
271 * Invalid cfg_space/offset/length combination in
272 * cfg_read/cfg_write.
274 tb_ctl_dbg(ctl, "%llx:%x: invalid config space or offset\n",
275 res->response_route, res->response_port);
276 return;
277 case TB_CFG_ERROR_NO_SUCH_PORT:
279 * - The route contains a non-existent port.
280 * - The route contains a non-PHY port (e.g. PCIe).
281 * - The port in cfg_read/cfg_write does not exist.
283 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Invalid port\n",
284 res->response_route, res->response_port);
285 return;
286 case TB_CFG_ERROR_LOOP:
287 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Route contains a loop\n",
288 res->response_route, res->response_port);
289 return;
290 case TB_CFG_ERROR_LOCK:
291 tb_ctl_warn(ctl, "%llx:%x: downstream port is locked\n",
292 res->response_route, res->response_port);
293 return;
294 default:
295 /* 5,6,7,9 and 11 are also valid error codes */
296 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Unknown error\n",
297 res->response_route, res->response_port);
298 return;
302 static __be32 tb_crc(const void *data, size_t len)
304 return cpu_to_be32(~__crc32c_le(~0, data, len));
307 static void tb_ctl_pkg_free(struct ctl_pkg *pkg)
309 if (pkg) {
310 dma_pool_free(pkg->ctl->frame_pool,
311 pkg->buffer, pkg->frame.buffer_phy);
312 kfree(pkg);
316 static struct ctl_pkg *tb_ctl_pkg_alloc(struct tb_ctl *ctl)
318 struct ctl_pkg *pkg = kzalloc(sizeof(*pkg), GFP_KERNEL);
319 if (!pkg)
320 return NULL;
321 pkg->ctl = ctl;
322 pkg->buffer = dma_pool_alloc(ctl->frame_pool, GFP_KERNEL,
323 &pkg->frame.buffer_phy);
324 if (!pkg->buffer) {
325 kfree(pkg);
326 return NULL;
328 return pkg;
332 /* RX/TX handling */
334 static void tb_ctl_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
335 bool canceled)
337 struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame);
338 tb_ctl_pkg_free(pkg);
342 * tb_cfg_tx() - transmit a packet on the control channel
344 * len must be a multiple of four.
346 * Return: Returns 0 on success or an error code on failure.
348 static int tb_ctl_tx(struct tb_ctl *ctl, const void *data, size_t len,
349 enum tb_cfg_pkg_type type)
351 int res;
352 struct ctl_pkg *pkg;
353 if (len % 4 != 0) { /* required for le->be conversion */
354 tb_ctl_WARN(ctl, "TX: invalid size: %zu\n", len);
355 return -EINVAL;
357 if (len > TB_FRAME_SIZE - 4) { /* checksum is 4 bytes */
358 tb_ctl_WARN(ctl, "TX: packet too large: %zu/%d\n",
359 len, TB_FRAME_SIZE - 4);
360 return -EINVAL;
362 pkg = tb_ctl_pkg_alloc(ctl);
363 if (!pkg)
364 return -ENOMEM;
365 pkg->frame.callback = tb_ctl_tx_callback;
366 pkg->frame.size = len + 4;
367 pkg->frame.sof = type;
368 pkg->frame.eof = type;
369 cpu_to_be32_array(pkg->buffer, data, len / 4);
370 *(__be32 *) (pkg->buffer + len) = tb_crc(pkg->buffer, len);
372 res = tb_ring_tx(ctl->tx, &pkg->frame);
373 if (res) /* ring is stopped */
374 tb_ctl_pkg_free(pkg);
375 return res;
379 * tb_ctl_handle_event() - acknowledge a plug event, invoke ctl->callback
381 static bool tb_ctl_handle_event(struct tb_ctl *ctl, enum tb_cfg_pkg_type type,
382 struct ctl_pkg *pkg, size_t size)
384 return ctl->callback(ctl->callback_data, type, pkg->buffer, size);
387 static void tb_ctl_rx_submit(struct ctl_pkg *pkg)
389 tb_ring_rx(pkg->ctl->rx, &pkg->frame); /*
390 * We ignore failures during stop.
391 * All rx packets are referenced
392 * from ctl->rx_packets, so we do
393 * not loose them.
397 static int tb_async_error(const struct ctl_pkg *pkg)
399 const struct cfg_error_pkg *error = (const struct cfg_error_pkg *)pkg;
401 if (pkg->frame.eof != TB_CFG_PKG_ERROR)
402 return false;
404 switch (error->error) {
405 case TB_CFG_ERROR_LINK_ERROR:
406 case TB_CFG_ERROR_HEC_ERROR_DETECTED:
407 case TB_CFG_ERROR_FLOW_CONTROL_ERROR:
408 return true;
410 default:
411 return false;
415 static void tb_ctl_rx_callback(struct tb_ring *ring, struct ring_frame *frame,
416 bool canceled)
418 struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame);
419 struct tb_cfg_request *req;
420 __be32 crc32;
422 if (canceled)
423 return; /*
424 * ring is stopped, packet is referenced from
425 * ctl->rx_packets.
428 if (frame->size < 4 || frame->size % 4 != 0) {
429 tb_ctl_err(pkg->ctl, "RX: invalid size %#x, dropping packet\n",
430 frame->size);
431 goto rx;
434 frame->size -= 4; /* remove checksum */
435 crc32 = tb_crc(pkg->buffer, frame->size);
436 be32_to_cpu_array(pkg->buffer, pkg->buffer, frame->size / 4);
438 switch (frame->eof) {
439 case TB_CFG_PKG_READ:
440 case TB_CFG_PKG_WRITE:
441 case TB_CFG_PKG_ERROR:
442 case TB_CFG_PKG_OVERRIDE:
443 case TB_CFG_PKG_RESET:
444 if (*(__be32 *)(pkg->buffer + frame->size) != crc32) {
445 tb_ctl_err(pkg->ctl,
446 "RX: checksum mismatch, dropping packet\n");
447 goto rx;
449 if (tb_async_error(pkg)) {
450 tb_ctl_handle_event(pkg->ctl, frame->eof,
451 pkg, frame->size);
452 goto rx;
454 break;
456 case TB_CFG_PKG_EVENT:
457 case TB_CFG_PKG_XDOMAIN_RESP:
458 case TB_CFG_PKG_XDOMAIN_REQ:
459 if (*(__be32 *)(pkg->buffer + frame->size) != crc32) {
460 tb_ctl_err(pkg->ctl,
461 "RX: checksum mismatch, dropping packet\n");
462 goto rx;
464 fallthrough;
465 case TB_CFG_PKG_ICM_EVENT:
466 if (tb_ctl_handle_event(pkg->ctl, frame->eof, pkg, frame->size))
467 goto rx;
468 break;
470 default:
471 break;
475 * The received packet will be processed only if there is an
476 * active request and that the packet is what is expected. This
477 * prevents packets such as replies coming after timeout has
478 * triggered from messing with the active requests.
480 req = tb_cfg_request_find(pkg->ctl, pkg);
481 if (req) {
482 if (req->copy(req, pkg))
483 schedule_work(&req->work);
484 tb_cfg_request_put(req);
488 tb_ctl_rx_submit(pkg);
491 static void tb_cfg_request_work(struct work_struct *work)
493 struct tb_cfg_request *req = container_of(work, typeof(*req), work);
495 if (!test_bit(TB_CFG_REQUEST_CANCELED, &req->flags))
496 req->callback(req->callback_data);
498 tb_cfg_request_dequeue(req);
499 tb_cfg_request_put(req);
503 * tb_cfg_request() - Start control request not waiting for it to complete
504 * @ctl: Control channel to use
505 * @req: Request to start
506 * @callback: Callback called when the request is completed
507 * @callback_data: Data to be passed to @callback
509 * This queues @req on the given control channel without waiting for it
510 * to complete. When the request completes @callback is called.
512 int tb_cfg_request(struct tb_ctl *ctl, struct tb_cfg_request *req,
513 void (*callback)(void *), void *callback_data)
515 int ret;
517 req->flags = 0;
518 req->callback = callback;
519 req->callback_data = callback_data;
520 INIT_WORK(&req->work, tb_cfg_request_work);
521 INIT_LIST_HEAD(&req->list);
523 tb_cfg_request_get(req);
524 ret = tb_cfg_request_enqueue(ctl, req);
525 if (ret)
526 goto err_put;
528 ret = tb_ctl_tx(ctl, req->request, req->request_size,
529 req->request_type);
530 if (ret)
531 goto err_dequeue;
533 if (!req->response)
534 schedule_work(&req->work);
536 return 0;
538 err_dequeue:
539 tb_cfg_request_dequeue(req);
540 err_put:
541 tb_cfg_request_put(req);
543 return ret;
547 * tb_cfg_request_cancel() - Cancel a control request
548 * @req: Request to cancel
549 * @err: Error to assign to the request
551 * This function can be used to cancel ongoing request. It will wait
552 * until the request is not active anymore.
554 void tb_cfg_request_cancel(struct tb_cfg_request *req, int err)
556 set_bit(TB_CFG_REQUEST_CANCELED, &req->flags);
557 schedule_work(&req->work);
558 wait_event(tb_cfg_request_cancel_queue, !tb_cfg_request_is_active(req));
559 req->result.err = err;
562 static void tb_cfg_request_complete(void *data)
564 complete(data);
568 * tb_cfg_request_sync() - Start control request and wait until it completes
569 * @ctl: Control channel to use
570 * @req: Request to start
571 * @timeout_msec: Timeout how long to wait @req to complete
573 * Starts a control request and waits until it completes. If timeout
574 * triggers the request is canceled before function returns. Note the
575 * caller needs to make sure only one message for given switch is active
576 * at a time.
578 struct tb_cfg_result tb_cfg_request_sync(struct tb_ctl *ctl,
579 struct tb_cfg_request *req,
580 int timeout_msec)
582 unsigned long timeout = msecs_to_jiffies(timeout_msec);
583 struct tb_cfg_result res = { 0 };
584 DECLARE_COMPLETION_ONSTACK(done);
585 int ret;
587 ret = tb_cfg_request(ctl, req, tb_cfg_request_complete, &done);
588 if (ret) {
589 res.err = ret;
590 return res;
593 if (!wait_for_completion_timeout(&done, timeout))
594 tb_cfg_request_cancel(req, -ETIMEDOUT);
596 flush_work(&req->work);
598 return req->result;
601 /* public interface, alloc/start/stop/free */
604 * tb_ctl_alloc() - allocate a control channel
606 * cb will be invoked once for every hot plug event.
608 * Return: Returns a pointer on success or NULL on failure.
610 struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data)
612 int i;
613 struct tb_ctl *ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
614 if (!ctl)
615 return NULL;
616 ctl->nhi = nhi;
617 ctl->callback = cb;
618 ctl->callback_data = cb_data;
620 mutex_init(&ctl->request_queue_lock);
621 INIT_LIST_HEAD(&ctl->request_queue);
622 ctl->frame_pool = dma_pool_create("thunderbolt_ctl", &nhi->pdev->dev,
623 TB_FRAME_SIZE, 4, 0);
624 if (!ctl->frame_pool)
625 goto err;
627 ctl->tx = tb_ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
628 if (!ctl->tx)
629 goto err;
631 ctl->rx = tb_ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0, 0xffff,
632 0xffff, NULL, NULL);
633 if (!ctl->rx)
634 goto err;
636 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) {
637 ctl->rx_packets[i] = tb_ctl_pkg_alloc(ctl);
638 if (!ctl->rx_packets[i])
639 goto err;
640 ctl->rx_packets[i]->frame.callback = tb_ctl_rx_callback;
643 tb_ctl_dbg(ctl, "control channel created\n");
644 return ctl;
645 err:
646 tb_ctl_free(ctl);
647 return NULL;
651 * tb_ctl_free() - free a control channel
653 * Must be called after tb_ctl_stop.
655 * Must NOT be called from ctl->callback.
657 void tb_ctl_free(struct tb_ctl *ctl)
659 int i;
661 if (!ctl)
662 return;
664 if (ctl->rx)
665 tb_ring_free(ctl->rx);
666 if (ctl->tx)
667 tb_ring_free(ctl->tx);
669 /* free RX packets */
670 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
671 tb_ctl_pkg_free(ctl->rx_packets[i]);
674 dma_pool_destroy(ctl->frame_pool);
675 kfree(ctl);
679 * tb_cfg_start() - start/resume the control channel
681 void tb_ctl_start(struct tb_ctl *ctl)
683 int i;
684 tb_ctl_dbg(ctl, "control channel starting...\n");
685 tb_ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
686 tb_ring_start(ctl->rx);
687 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
688 tb_ctl_rx_submit(ctl->rx_packets[i]);
690 ctl->running = true;
694 * control() - pause the control channel
696 * All invocations of ctl->callback will have finished after this method
697 * returns.
699 * Must NOT be called from ctl->callback.
701 void tb_ctl_stop(struct tb_ctl *ctl)
703 mutex_lock(&ctl->request_queue_lock);
704 ctl->running = false;
705 mutex_unlock(&ctl->request_queue_lock);
707 tb_ring_stop(ctl->rx);
708 tb_ring_stop(ctl->tx);
710 if (!list_empty(&ctl->request_queue))
711 tb_ctl_WARN(ctl, "dangling request in request_queue\n");
712 INIT_LIST_HEAD(&ctl->request_queue);
713 tb_ctl_dbg(ctl, "control channel stopped\n");
716 /* public interface, commands */
719 * tb_cfg_ack_plug() - Ack hot plug/unplug event
720 * @ctl: Control channel to use
721 * @route: Router that originated the event
722 * @port: Port where the hot plug/unplug happened
723 * @unplug: Ack hot plug or unplug
725 * Call this as response for hot plug/unplug event to ack it.
726 * Returns %0 on success or an error code on failure.
728 int tb_cfg_ack_plug(struct tb_ctl *ctl, u64 route, u32 port, bool unplug)
730 struct cfg_error_pkg pkg = {
731 .header = tb_cfg_make_header(route),
732 .port = port,
733 .error = TB_CFG_ERROR_ACK_PLUG_EVENT,
734 .pg = unplug ? TB_CFG_ERROR_PG_HOT_UNPLUG
735 : TB_CFG_ERROR_PG_HOT_PLUG,
737 tb_ctl_dbg(ctl, "acking hot %splug event on %llx:%x\n",
738 unplug ? "un" : "", route, port);
739 return tb_ctl_tx(ctl, &pkg, sizeof(pkg), TB_CFG_PKG_ERROR);
742 static bool tb_cfg_match(const struct tb_cfg_request *req,
743 const struct ctl_pkg *pkg)
745 u64 route = tb_cfg_get_route(pkg->buffer) & ~BIT_ULL(63);
747 if (pkg->frame.eof == TB_CFG_PKG_ERROR)
748 return true;
750 if (pkg->frame.eof != req->response_type)
751 return false;
752 if (route != tb_cfg_get_route(req->request))
753 return false;
754 if (pkg->frame.size != req->response_size)
755 return false;
757 if (pkg->frame.eof == TB_CFG_PKG_READ ||
758 pkg->frame.eof == TB_CFG_PKG_WRITE) {
759 const struct cfg_read_pkg *req_hdr = req->request;
760 const struct cfg_read_pkg *res_hdr = pkg->buffer;
762 if (req_hdr->addr.seq != res_hdr->addr.seq)
763 return false;
766 return true;
769 static bool tb_cfg_copy(struct tb_cfg_request *req, const struct ctl_pkg *pkg)
771 struct tb_cfg_result res;
773 /* Now make sure it is in expected format */
774 res = parse_header(pkg, req->response_size, req->response_type,
775 tb_cfg_get_route(req->request));
776 if (!res.err)
777 memcpy(req->response, pkg->buffer, req->response_size);
779 req->result = res;
781 /* Always complete when first response is received */
782 return true;
786 * tb_cfg_reset() - send a reset packet and wait for a response
788 * If the switch at route is incorrectly configured then we will not receive a
789 * reply (even though the switch will reset). The caller should check for
790 * -ETIMEDOUT and attempt to reconfigure the switch.
792 struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route,
793 int timeout_msec)
795 struct cfg_reset_pkg request = { .header = tb_cfg_make_header(route) };
796 struct tb_cfg_result res = { 0 };
797 struct tb_cfg_header reply;
798 struct tb_cfg_request *req;
800 req = tb_cfg_request_alloc();
801 if (!req) {
802 res.err = -ENOMEM;
803 return res;
806 req->match = tb_cfg_match;
807 req->copy = tb_cfg_copy;
808 req->request = &request;
809 req->request_size = sizeof(request);
810 req->request_type = TB_CFG_PKG_RESET;
811 req->response = &reply;
812 req->response_size = sizeof(reply);
813 req->response_type = TB_CFG_PKG_RESET;
815 res = tb_cfg_request_sync(ctl, req, timeout_msec);
817 tb_cfg_request_put(req);
819 return res;
823 * tb_cfg_read() - read from config space into buffer
825 * Offset and length are in dwords.
827 struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer,
828 u64 route, u32 port, enum tb_cfg_space space,
829 u32 offset, u32 length, int timeout_msec)
831 struct tb_cfg_result res = { 0 };
832 struct cfg_read_pkg request = {
833 .header = tb_cfg_make_header(route),
834 .addr = {
835 .port = port,
836 .space = space,
837 .offset = offset,
838 .length = length,
841 struct cfg_write_pkg reply;
842 int retries = 0;
844 while (retries < TB_CTL_RETRIES) {
845 struct tb_cfg_request *req;
847 req = tb_cfg_request_alloc();
848 if (!req) {
849 res.err = -ENOMEM;
850 return res;
853 request.addr.seq = retries++;
855 req->match = tb_cfg_match;
856 req->copy = tb_cfg_copy;
857 req->request = &request;
858 req->request_size = sizeof(request);
859 req->request_type = TB_CFG_PKG_READ;
860 req->response = &reply;
861 req->response_size = 12 + 4 * length;
862 req->response_type = TB_CFG_PKG_READ;
864 res = tb_cfg_request_sync(ctl, req, timeout_msec);
866 tb_cfg_request_put(req);
868 if (res.err != -ETIMEDOUT)
869 break;
871 /* Wait a bit (arbitrary time) until we send a retry */
872 usleep_range(10, 100);
875 if (res.err)
876 return res;
878 res.response_port = reply.addr.port;
879 res.err = check_config_address(reply.addr, space, offset, length);
880 if (!res.err)
881 memcpy(buffer, &reply.data, 4 * length);
882 return res;
886 * tb_cfg_write() - write from buffer into config space
888 * Offset and length are in dwords.
890 struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, const void *buffer,
891 u64 route, u32 port, enum tb_cfg_space space,
892 u32 offset, u32 length, int timeout_msec)
894 struct tb_cfg_result res = { 0 };
895 struct cfg_write_pkg request = {
896 .header = tb_cfg_make_header(route),
897 .addr = {
898 .port = port,
899 .space = space,
900 .offset = offset,
901 .length = length,
904 struct cfg_read_pkg reply;
905 int retries = 0;
907 memcpy(&request.data, buffer, length * 4);
909 while (retries < TB_CTL_RETRIES) {
910 struct tb_cfg_request *req;
912 req = tb_cfg_request_alloc();
913 if (!req) {
914 res.err = -ENOMEM;
915 return res;
918 request.addr.seq = retries++;
920 req->match = tb_cfg_match;
921 req->copy = tb_cfg_copy;
922 req->request = &request;
923 req->request_size = 12 + 4 * length;
924 req->request_type = TB_CFG_PKG_WRITE;
925 req->response = &reply;
926 req->response_size = sizeof(reply);
927 req->response_type = TB_CFG_PKG_WRITE;
929 res = tb_cfg_request_sync(ctl, req, timeout_msec);
931 tb_cfg_request_put(req);
933 if (res.err != -ETIMEDOUT)
934 break;
936 /* Wait a bit (arbitrary time) until we send a retry */
937 usleep_range(10, 100);
940 if (res.err)
941 return res;
943 res.response_port = reply.addr.port;
944 res.err = check_config_address(reply.addr, space, offset, length);
945 return res;
948 static int tb_cfg_get_error(struct tb_ctl *ctl, enum tb_cfg_space space,
949 const struct tb_cfg_result *res)
952 * For unimplemented ports access to port config space may return
953 * TB_CFG_ERROR_INVALID_CONFIG_SPACE (alternatively their type is
954 * set to TB_TYPE_INACTIVE). In the former case return -ENODEV so
955 * that the caller can mark the port as disabled.
957 if (space == TB_CFG_PORT &&
958 res->tb_error == TB_CFG_ERROR_INVALID_CONFIG_SPACE)
959 return -ENODEV;
961 tb_cfg_print_error(ctl, res);
963 if (res->tb_error == TB_CFG_ERROR_LOCK)
964 return -EACCES;
965 else if (res->tb_error == TB_CFG_ERROR_PORT_NOT_CONNECTED)
966 return -ENOTCONN;
968 return -EIO;
971 int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
972 enum tb_cfg_space space, u32 offset, u32 length)
974 struct tb_cfg_result res = tb_cfg_read_raw(ctl, buffer, route, port,
975 space, offset, length, TB_CFG_DEFAULT_TIMEOUT);
976 switch (res.err) {
977 case 0:
978 /* Success */
979 break;
981 case 1:
982 /* Thunderbolt error, tb_error holds the actual number */
983 return tb_cfg_get_error(ctl, space, &res);
985 case -ETIMEDOUT:
986 tb_ctl_warn(ctl, "%llx: timeout reading config space %u from %#x\n",
987 route, space, offset);
988 break;
990 default:
991 WARN(1, "tb_cfg_read: %d\n", res.err);
992 break;
994 return res.err;
997 int tb_cfg_write(struct tb_ctl *ctl, const void *buffer, u64 route, u32 port,
998 enum tb_cfg_space space, u32 offset, u32 length)
1000 struct tb_cfg_result res = tb_cfg_write_raw(ctl, buffer, route, port,
1001 space, offset, length, TB_CFG_DEFAULT_TIMEOUT);
1002 switch (res.err) {
1003 case 0:
1004 /* Success */
1005 break;
1007 case 1:
1008 /* Thunderbolt error, tb_error holds the actual number */
1009 return tb_cfg_get_error(ctl, space, &res);
1011 case -ETIMEDOUT:
1012 tb_ctl_warn(ctl, "%llx: timeout writing config space %u to %#x\n",
1013 route, space, offset);
1014 break;
1016 default:
1017 WARN(1, "tb_cfg_write: %d\n", res.err);
1018 break;
1020 return res.err;
1024 * tb_cfg_get_upstream_port() - get upstream port number of switch at route
1026 * Reads the first dword from the switches TB_CFG_SWITCH config area and
1027 * returns the port number from which the reply originated.
1029 * Return: Returns the upstream port number on success or an error code on
1030 * failure.
1032 int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route)
1034 u32 dummy;
1035 struct tb_cfg_result res = tb_cfg_read_raw(ctl, &dummy, route, 0,
1036 TB_CFG_SWITCH, 0, 1,
1037 TB_CFG_DEFAULT_TIMEOUT);
1038 if (res.err == 1)
1039 return -EIO;
1040 if (res.err)
1041 return res.err;
1042 return res.response_port;