1 // SPDX-License-Identifier: GPL-2.0
3 * Thunderbolt driver - control channel and configuration commands
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6 * Copyright (C) 2018, Intel Corporation
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>
19 #define TB_CTL_RX_PKG_COUNT 10
20 #define TB_CTL_RETRIES 4
23 * struct tb_cfg - thunderbolt control channel
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;
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);
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);
74 kref_init(&req->kref);
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);
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);
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));
117 mutex_lock(&ctl->request_queue_lock);
119 mutex_unlock(&ctl->request_queue_lock);
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);
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;
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)) {
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))
179 if (WARN(type != pkg->frame.eof, "wrong eof (expected %#x, got %#x)\n",
180 type, pkg->frame.eof))
182 if (WARN(pkg->frame.sof, "wrong sof (expected 0x0, got %#x)\n",
187 if (WARN(header->unknown != 1 << 9,
188 "header->unknown is %#x\n", header->unknown))
190 if (WARN(route != tb_cfg_get_route(header),
191 "wrong route (expected %llx, got %llx)",
192 route, tb_cfg_get_route(header)))
197 static int check_config_address(struct tb_cfg_address addr,
198 enum tb_cfg_space space, u32 offset,
201 if (WARN(addr.zero, "addr.zero is %#x\n", addr.zero))
203 if (WARN(space != addr.space, "wrong space (expected %x, got %x\n)",
206 if (WARN(offset != addr.offset, "wrong offset (expected %x, got %x\n)",
207 offset, addr.offset))
209 if (WARN(length != addr.length, "wrong space (expected %x, got %x\n)",
210 length, addr.length))
213 * We cannot check addr->port as it is set to the upstream port of the
219 static struct tb_cfg_result decode_error(const struct ctl_pkg *response)
221 struct cfg_error_pkg *pkg = response->buffer;
222 struct tb_cfg_result res = { 0 };
223 res.response_route = tb_cfg_get_route(&pkg->header);
224 res.response_port = 0;
225 res.err = check_header(response, sizeof(*pkg), TB_CFG_PKG_ERROR,
226 tb_cfg_get_route(&pkg->header));
230 WARN(pkg->zero1, "pkg->zero1 is %#x\n", pkg->zero1);
231 WARN(pkg->zero2, "pkg->zero1 is %#x\n", pkg->zero1);
232 WARN(pkg->zero3, "pkg->zero1 is %#x\n", pkg->zero1);
234 res.tb_error = pkg->error;
235 res.response_port = pkg->port;
240 static struct tb_cfg_result parse_header(const struct ctl_pkg *pkg, u32 len,
241 enum tb_cfg_pkg_type type, u64 route)
243 struct tb_cfg_header *header = pkg->buffer;
244 struct tb_cfg_result res = { 0 };
246 if (pkg->frame.eof == TB_CFG_PKG_ERROR)
247 return decode_error(pkg);
249 res.response_port = 0; /* will be updated later for cfg_read/write */
250 res.response_route = tb_cfg_get_route(header);
251 res.err = check_header(pkg, len, type, route);
255 static void tb_cfg_print_error(struct tb_ctl *ctl,
256 const struct tb_cfg_result *res)
258 WARN_ON(res->err != 1);
259 switch (res->tb_error) {
260 case TB_CFG_ERROR_PORT_NOT_CONNECTED:
261 /* Port is not connected. This can happen during surprise
262 * removal. Do not warn. */
264 case TB_CFG_ERROR_INVALID_CONFIG_SPACE:
266 * Invalid cfg_space/offset/length combination in
267 * cfg_read/cfg_write.
269 tb_ctl_dbg(ctl, "%llx:%x: invalid config space or offset\n",
270 res->response_route, res->response_port);
272 case TB_CFG_ERROR_NO_SUCH_PORT:
274 * - The route contains a non-existent port.
275 * - The route contains a non-PHY port (e.g. PCIe).
276 * - The port in cfg_read/cfg_write does not exist.
278 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Invalid port\n",
279 res->response_route, res->response_port);
281 case TB_CFG_ERROR_LOOP:
282 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Route contains a loop\n",
283 res->response_route, res->response_port);
285 case TB_CFG_ERROR_LOCK:
286 tb_ctl_warn(ctl, "%llx:%x: downstream port is locked\n",
287 res->response_route, res->response_port);
290 /* 5,6,7,9 and 11 are also valid error codes */
291 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Unknown error\n",
292 res->response_route, res->response_port);
297 static __be32 tb_crc(const void *data, size_t len)
299 return cpu_to_be32(~__crc32c_le(~0, data, len));
302 static void tb_ctl_pkg_free(struct ctl_pkg *pkg)
305 dma_pool_free(pkg->ctl->frame_pool,
306 pkg->buffer, pkg->frame.buffer_phy);
311 static struct ctl_pkg *tb_ctl_pkg_alloc(struct tb_ctl *ctl)
313 struct ctl_pkg *pkg = kzalloc(sizeof(*pkg), GFP_KERNEL);
317 pkg->buffer = dma_pool_alloc(ctl->frame_pool, GFP_KERNEL,
318 &pkg->frame.buffer_phy);
329 static void tb_ctl_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
332 struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame);
333 tb_ctl_pkg_free(pkg);
337 * tb_cfg_tx() - transmit a packet on the control channel
339 * len must be a multiple of four.
341 * Return: Returns 0 on success or an error code on failure.
343 static int tb_ctl_tx(struct tb_ctl *ctl, const void *data, size_t len,
344 enum tb_cfg_pkg_type type)
348 if (len % 4 != 0) { /* required for le->be conversion */
349 tb_ctl_WARN(ctl, "TX: invalid size: %zu\n", len);
352 if (len > TB_FRAME_SIZE - 4) { /* checksum is 4 bytes */
353 tb_ctl_WARN(ctl, "TX: packet too large: %zu/%d\n",
354 len, TB_FRAME_SIZE - 4);
357 pkg = tb_ctl_pkg_alloc(ctl);
360 pkg->frame.callback = tb_ctl_tx_callback;
361 pkg->frame.size = len + 4;
362 pkg->frame.sof = type;
363 pkg->frame.eof = type;
364 cpu_to_be32_array(pkg->buffer, data, len / 4);
365 *(__be32 *) (pkg->buffer + len) = tb_crc(pkg->buffer, len);
367 res = tb_ring_tx(ctl->tx, &pkg->frame);
368 if (res) /* ring is stopped */
369 tb_ctl_pkg_free(pkg);
374 * tb_ctl_handle_event() - acknowledge a plug event, invoke ctl->callback
376 static bool tb_ctl_handle_event(struct tb_ctl *ctl, enum tb_cfg_pkg_type type,
377 struct ctl_pkg *pkg, size_t size)
379 return ctl->callback(ctl->callback_data, type, pkg->buffer, size);
382 static void tb_ctl_rx_submit(struct ctl_pkg *pkg)
384 tb_ring_rx(pkg->ctl->rx, &pkg->frame); /*
385 * We ignore failures during stop.
386 * All rx packets are referenced
387 * from ctl->rx_packets, so we do
392 static int tb_async_error(const struct ctl_pkg *pkg)
394 const struct cfg_error_pkg *error = (const struct cfg_error_pkg *)pkg;
396 if (pkg->frame.eof != TB_CFG_PKG_ERROR)
399 switch (error->error) {
400 case TB_CFG_ERROR_LINK_ERROR:
401 case TB_CFG_ERROR_HEC_ERROR_DETECTED:
402 case TB_CFG_ERROR_FLOW_CONTROL_ERROR:
410 static void tb_ctl_rx_callback(struct tb_ring *ring, struct ring_frame *frame,
413 struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame);
414 struct tb_cfg_request *req;
419 * ring is stopped, packet is referenced from
423 if (frame->size < 4 || frame->size % 4 != 0) {
424 tb_ctl_err(pkg->ctl, "RX: invalid size %#x, dropping packet\n",
429 frame->size -= 4; /* remove checksum */
430 crc32 = tb_crc(pkg->buffer, frame->size);
431 be32_to_cpu_array(pkg->buffer, pkg->buffer, frame->size / 4);
433 switch (frame->eof) {
434 case TB_CFG_PKG_READ:
435 case TB_CFG_PKG_WRITE:
436 case TB_CFG_PKG_ERROR:
437 case TB_CFG_PKG_OVERRIDE:
438 case TB_CFG_PKG_RESET:
439 if (*(__be32 *)(pkg->buffer + frame->size) != crc32) {
441 "RX: checksum mismatch, dropping packet\n");
444 if (tb_async_error(pkg)) {
445 tb_ctl_handle_event(pkg->ctl, frame->eof,
451 case TB_CFG_PKG_EVENT:
452 case TB_CFG_PKG_XDOMAIN_RESP:
453 case TB_CFG_PKG_XDOMAIN_REQ:
454 if (*(__be32 *)(pkg->buffer + frame->size) != crc32) {
456 "RX: checksum mismatch, dropping packet\n");
460 case TB_CFG_PKG_ICM_EVENT:
461 if (tb_ctl_handle_event(pkg->ctl, frame->eof, pkg, frame->size))
470 * The received packet will be processed only if there is an
471 * active request and that the packet is what is expected. This
472 * prevents packets such as replies coming after timeout has
473 * triggered from messing with the active requests.
475 req = tb_cfg_request_find(pkg->ctl, pkg);
477 if (req->copy(req, pkg))
478 schedule_work(&req->work);
479 tb_cfg_request_put(req);
483 tb_ctl_rx_submit(pkg);
486 static void tb_cfg_request_work(struct work_struct *work)
488 struct tb_cfg_request *req = container_of(work, typeof(*req), work);
490 if (!test_bit(TB_CFG_REQUEST_CANCELED, &req->flags))
491 req->callback(req->callback_data);
493 tb_cfg_request_dequeue(req);
494 tb_cfg_request_put(req);
498 * tb_cfg_request() - Start control request not waiting for it to complete
499 * @ctl: Control channel to use
500 * @req: Request to start
501 * @callback: Callback called when the request is completed
502 * @callback_data: Data to be passed to @callback
504 * This queues @req on the given control channel without waiting for it
505 * to complete. When the request completes @callback is called.
507 int tb_cfg_request(struct tb_ctl *ctl, struct tb_cfg_request *req,
508 void (*callback)(void *), void *callback_data)
513 req->callback = callback;
514 req->callback_data = callback_data;
515 INIT_WORK(&req->work, tb_cfg_request_work);
516 INIT_LIST_HEAD(&req->list);
518 tb_cfg_request_get(req);
519 ret = tb_cfg_request_enqueue(ctl, req);
523 ret = tb_ctl_tx(ctl, req->request, req->request_size,
529 schedule_work(&req->work);
534 tb_cfg_request_dequeue(req);
536 tb_cfg_request_put(req);
542 * tb_cfg_request_cancel() - Cancel a control request
543 * @req: Request to cancel
544 * @err: Error to assign to the request
546 * This function can be used to cancel ongoing request. It will wait
547 * until the request is not active anymore.
549 void tb_cfg_request_cancel(struct tb_cfg_request *req, int err)
551 set_bit(TB_CFG_REQUEST_CANCELED, &req->flags);
552 schedule_work(&req->work);
553 wait_event(tb_cfg_request_cancel_queue, !tb_cfg_request_is_active(req));
554 req->result.err = err;
557 static void tb_cfg_request_complete(void *data)
563 * tb_cfg_request_sync() - Start control request and wait until it completes
564 * @ctl: Control channel to use
565 * @req: Request to start
566 * @timeout_msec: Timeout how long to wait @req to complete
568 * Starts a control request and waits until it completes. If timeout
569 * triggers the request is canceled before function returns. Note the
570 * caller needs to make sure only one message for given switch is active
573 struct tb_cfg_result tb_cfg_request_sync(struct tb_ctl *ctl,
574 struct tb_cfg_request *req,
577 unsigned long timeout = msecs_to_jiffies(timeout_msec);
578 struct tb_cfg_result res = { 0 };
579 DECLARE_COMPLETION_ONSTACK(done);
582 ret = tb_cfg_request(ctl, req, tb_cfg_request_complete, &done);
588 if (!wait_for_completion_timeout(&done, timeout))
589 tb_cfg_request_cancel(req, -ETIMEDOUT);
591 flush_work(&req->work);
596 /* public interface, alloc/start/stop/free */
599 * tb_ctl_alloc() - allocate a control channel
601 * cb will be invoked once for every hot plug event.
603 * Return: Returns a pointer on success or NULL on failure.
605 struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data)
608 struct tb_ctl *ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
613 ctl->callback_data = cb_data;
615 mutex_init(&ctl->request_queue_lock);
616 INIT_LIST_HEAD(&ctl->request_queue);
617 ctl->frame_pool = dma_pool_create("thunderbolt_ctl", &nhi->pdev->dev,
618 TB_FRAME_SIZE, 4, 0);
619 if (!ctl->frame_pool)
622 ctl->tx = tb_ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
626 ctl->rx = tb_ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
631 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) {
632 ctl->rx_packets[i] = tb_ctl_pkg_alloc(ctl);
633 if (!ctl->rx_packets[i])
635 ctl->rx_packets[i]->frame.callback = tb_ctl_rx_callback;
638 tb_ctl_dbg(ctl, "control channel created\n");
646 * tb_ctl_free() - free a control channel
648 * Must be called after tb_ctl_stop.
650 * Must NOT be called from ctl->callback.
652 void tb_ctl_free(struct tb_ctl *ctl)
660 tb_ring_free(ctl->rx);
662 tb_ring_free(ctl->tx);
664 /* free RX packets */
665 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
666 tb_ctl_pkg_free(ctl->rx_packets[i]);
669 dma_pool_destroy(ctl->frame_pool);
674 * tb_cfg_start() - start/resume the control channel
676 void tb_ctl_start(struct tb_ctl *ctl)
679 tb_ctl_dbg(ctl, "control channel starting...\n");
680 tb_ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
681 tb_ring_start(ctl->rx);
682 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
683 tb_ctl_rx_submit(ctl->rx_packets[i]);
689 * control() - pause the control channel
691 * All invocations of ctl->callback will have finished after this method
694 * Must NOT be called from ctl->callback.
696 void tb_ctl_stop(struct tb_ctl *ctl)
698 mutex_lock(&ctl->request_queue_lock);
699 ctl->running = false;
700 mutex_unlock(&ctl->request_queue_lock);
702 tb_ring_stop(ctl->rx);
703 tb_ring_stop(ctl->tx);
705 if (!list_empty(&ctl->request_queue))
706 tb_ctl_WARN(ctl, "dangling request in request_queue\n");
707 INIT_LIST_HEAD(&ctl->request_queue);
708 tb_ctl_dbg(ctl, "control channel stopped\n");
711 /* public interface, commands */
714 * tb_cfg_ack_plug() - Ack hot plug/unplug event
715 * @ctl: Control channel to use
716 * @route: Router that originated the event
717 * @port: Port where the hot plug/unplug happened
718 * @unplug: Ack hot plug or unplug
720 * Call this as response for hot plug/unplug event to ack it.
721 * Returns %0 on success or an error code on failure.
723 int tb_cfg_ack_plug(struct tb_ctl *ctl, u64 route, u32 port, bool unplug)
725 struct cfg_error_pkg pkg = {
726 .header = tb_cfg_make_header(route),
728 .error = TB_CFG_ERROR_ACK_PLUG_EVENT,
729 .pg = unplug ? TB_CFG_ERROR_PG_HOT_UNPLUG
730 : TB_CFG_ERROR_PG_HOT_PLUG,
732 tb_ctl_dbg(ctl, "acking hot %splug event on %llx:%x\n",
733 unplug ? "un" : "", route, port);
734 return tb_ctl_tx(ctl, &pkg, sizeof(pkg), TB_CFG_PKG_ERROR);
737 static bool tb_cfg_match(const struct tb_cfg_request *req,
738 const struct ctl_pkg *pkg)
740 u64 route = tb_cfg_get_route(pkg->buffer) & ~BIT_ULL(63);
742 if (pkg->frame.eof == TB_CFG_PKG_ERROR)
745 if (pkg->frame.eof != req->response_type)
747 if (route != tb_cfg_get_route(req->request))
749 if (pkg->frame.size != req->response_size)
752 if (pkg->frame.eof == TB_CFG_PKG_READ ||
753 pkg->frame.eof == TB_CFG_PKG_WRITE) {
754 const struct cfg_read_pkg *req_hdr = req->request;
755 const struct cfg_read_pkg *res_hdr = pkg->buffer;
757 if (req_hdr->addr.seq != res_hdr->addr.seq)
764 static bool tb_cfg_copy(struct tb_cfg_request *req, const struct ctl_pkg *pkg)
766 struct tb_cfg_result res;
768 /* Now make sure it is in expected format */
769 res = parse_header(pkg, req->response_size, req->response_type,
770 tb_cfg_get_route(req->request));
772 memcpy(req->response, pkg->buffer, req->response_size);
776 /* Always complete when first response is received */
781 * tb_cfg_reset() - send a reset packet and wait for a response
783 * If the switch at route is incorrectly configured then we will not receive a
784 * reply (even though the switch will reset). The caller should check for
785 * -ETIMEDOUT and attempt to reconfigure the switch.
787 struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route,
790 struct cfg_reset_pkg request = { .header = tb_cfg_make_header(route) };
791 struct tb_cfg_result res = { 0 };
792 struct tb_cfg_header reply;
793 struct tb_cfg_request *req;
795 req = tb_cfg_request_alloc();
801 req->match = tb_cfg_match;
802 req->copy = tb_cfg_copy;
803 req->request = &request;
804 req->request_size = sizeof(request);
805 req->request_type = TB_CFG_PKG_RESET;
806 req->response = &reply;
807 req->response_size = sizeof(reply);
808 req->response_type = TB_CFG_PKG_RESET;
810 res = tb_cfg_request_sync(ctl, req, timeout_msec);
812 tb_cfg_request_put(req);
818 * tb_cfg_read() - read from config space into buffer
820 * Offset and length are in dwords.
822 struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer,
823 u64 route, u32 port, enum tb_cfg_space space,
824 u32 offset, u32 length, int timeout_msec)
826 struct tb_cfg_result res = { 0 };
827 struct cfg_read_pkg request = {
828 .header = tb_cfg_make_header(route),
836 struct cfg_write_pkg reply;
839 while (retries < TB_CTL_RETRIES) {
840 struct tb_cfg_request *req;
842 req = tb_cfg_request_alloc();
848 request.addr.seq = retries++;
850 req->match = tb_cfg_match;
851 req->copy = tb_cfg_copy;
852 req->request = &request;
853 req->request_size = sizeof(request);
854 req->request_type = TB_CFG_PKG_READ;
855 req->response = &reply;
856 req->response_size = 12 + 4 * length;
857 req->response_type = TB_CFG_PKG_READ;
859 res = tb_cfg_request_sync(ctl, req, timeout_msec);
861 tb_cfg_request_put(req);
863 if (res.err != -ETIMEDOUT)
866 /* Wait a bit (arbitrary time) until we send a retry */
867 usleep_range(10, 100);
873 res.response_port = reply.addr.port;
874 res.err = check_config_address(reply.addr, space, offset, length);
876 memcpy(buffer, &reply.data, 4 * length);
881 * tb_cfg_write() - write from buffer into config space
883 * Offset and length are in dwords.
885 struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, const void *buffer,
886 u64 route, u32 port, enum tb_cfg_space space,
887 u32 offset, u32 length, int timeout_msec)
889 struct tb_cfg_result res = { 0 };
890 struct cfg_write_pkg request = {
891 .header = tb_cfg_make_header(route),
899 struct cfg_read_pkg reply;
902 memcpy(&request.data, buffer, length * 4);
904 while (retries < TB_CTL_RETRIES) {
905 struct tb_cfg_request *req;
907 req = tb_cfg_request_alloc();
913 request.addr.seq = retries++;
915 req->match = tb_cfg_match;
916 req->copy = tb_cfg_copy;
917 req->request = &request;
918 req->request_size = 12 + 4 * length;
919 req->request_type = TB_CFG_PKG_WRITE;
920 req->response = &reply;
921 req->response_size = sizeof(reply);
922 req->response_type = TB_CFG_PKG_WRITE;
924 res = tb_cfg_request_sync(ctl, req, timeout_msec);
926 tb_cfg_request_put(req);
928 if (res.err != -ETIMEDOUT)
931 /* Wait a bit (arbitrary time) until we send a retry */
932 usleep_range(10, 100);
938 res.response_port = reply.addr.port;
939 res.err = check_config_address(reply.addr, space, offset, length);
943 static int tb_cfg_get_error(struct tb_ctl *ctl, enum tb_cfg_space space,
944 const struct tb_cfg_result *res)
947 * For unimplemented ports access to port config space may return
948 * TB_CFG_ERROR_INVALID_CONFIG_SPACE (alternatively their type is
949 * set to TB_TYPE_INACTIVE). In the former case return -ENODEV so
950 * that the caller can mark the port as disabled.
952 if (space == TB_CFG_PORT &&
953 res->tb_error == TB_CFG_ERROR_INVALID_CONFIG_SPACE)
956 tb_cfg_print_error(ctl, res);
958 if (res->tb_error == TB_CFG_ERROR_LOCK)
963 int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
964 enum tb_cfg_space space, u32 offset, u32 length)
966 struct tb_cfg_result res = tb_cfg_read_raw(ctl, buffer, route, port,
967 space, offset, length, TB_CFG_DEFAULT_TIMEOUT);
974 /* Thunderbolt error, tb_error holds the actual number */
975 return tb_cfg_get_error(ctl, space, &res);
978 tb_ctl_warn(ctl, "%llx: timeout reading config space %u from %#x\n",
979 route, space, offset);
983 WARN(1, "tb_cfg_read: %d\n", res.err);
989 int tb_cfg_write(struct tb_ctl *ctl, const void *buffer, u64 route, u32 port,
990 enum tb_cfg_space space, u32 offset, u32 length)
992 struct tb_cfg_result res = tb_cfg_write_raw(ctl, buffer, route, port,
993 space, offset, length, TB_CFG_DEFAULT_TIMEOUT);
1000 /* Thunderbolt error, tb_error holds the actual number */
1001 return tb_cfg_get_error(ctl, space, &res);
1004 tb_ctl_warn(ctl, "%llx: timeout writing config space %u to %#x\n",
1005 route, space, offset);
1009 WARN(1, "tb_cfg_write: %d\n", res.err);
1016 * tb_cfg_get_upstream_port() - get upstream port number of switch at route
1018 * Reads the first dword from the switches TB_CFG_SWITCH config area and
1019 * returns the port number from which the reply originated.
1021 * Return: Returns the upstream port number on success or an error code on
1024 int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route)
1027 struct tb_cfg_result res = tb_cfg_read_raw(ctl, &dummy, route, 0,
1028 TB_CFG_SWITCH, 0, 1,
1029 TB_CFG_DEFAULT_TIMEOUT);
1034 return res.response_port;