blob: 799634b382c6f0a131fb9eadd31dc89984f16830 [file] [log] [blame]
Andreas Noeverf25bf6f2014-06-03 22:03:59 +02001/*
2 * Thunderbolt Cactus Ridge driver - control channel and configuration commands
3 *
4 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
5 */
6
7#include <linux/crc32.h>
8#include <linux/slab.h>
9#include <linux/pci.h>
10#include <linux/dmapool.h>
11#include <linux/workqueue.h>
12#include <linux/kfifo.h>
13
14#include "ctl.h"
15
16
17struct ctl_pkg {
18 struct tb_ctl *ctl;
19 void *buffer;
20 struct ring_frame frame;
21};
22
23#define TB_CTL_RX_PKG_COUNT 10
24
25/**
26 * struct tb_cfg - thunderbolt control channel
27 */
28struct tb_ctl {
29 struct tb_nhi *nhi;
30 struct tb_ring *tx;
31 struct tb_ring *rx;
32
33 struct dma_pool *frame_pool;
34 struct ctl_pkg *rx_packets[TB_CTL_RX_PKG_COUNT];
35 DECLARE_KFIFO(response_fifo, struct ctl_pkg*, 16);
36 struct completion response_ready;
37
38 hotplug_cb callback;
39 void *callback_data;
40};
41
42
43#define tb_ctl_WARN(ctl, format, arg...) \
44 dev_WARN(&(ctl)->nhi->pdev->dev, format, ## arg)
45
46#define tb_ctl_err(ctl, format, arg...) \
47 dev_err(&(ctl)->nhi->pdev->dev, format, ## arg)
48
49#define tb_ctl_warn(ctl, format, arg...) \
50 dev_warn(&(ctl)->nhi->pdev->dev, format, ## arg)
51
52#define tb_ctl_info(ctl, format, arg...) \
53 dev_info(&(ctl)->nhi->pdev->dev, format, ## arg)
54
55
56/* configuration packets definitions */
57
58enum tb_cfg_pkg_type {
59 TB_CFG_PKG_READ = 1,
60 TB_CFG_PKG_WRITE = 2,
61 TB_CFG_PKG_ERROR = 3,
62 TB_CFG_PKG_NOTIFY_ACK = 4,
63 TB_CFG_PKG_EVENT = 5,
64 TB_CFG_PKG_XDOMAIN_REQ = 6,
65 TB_CFG_PKG_XDOMAIN_RESP = 7,
66 TB_CFG_PKG_OVERRIDE = 8,
67 TB_CFG_PKG_RESET = 9,
68 TB_CFG_PKG_PREPARE_TO_SLEEP = 0xd,
69};
70
71/* common header */
72struct tb_cfg_header {
73 u32 route_hi:22;
74 u32 unknown:10; /* highest order bit is set on replies */
75 u32 route_lo;
76} __packed;
77
78/* additional header for read/write packets */
79struct tb_cfg_address {
80 u32 offset:13; /* in dwords */
81 u32 length:6; /* in dwords */
82 u32 port:6;
83 enum tb_cfg_space space:2;
84 u32 seq:2; /* sequence number */
85 u32 zero:3;
86} __packed;
87
88/* TB_CFG_PKG_READ, response for TB_CFG_PKG_WRITE */
89struct cfg_read_pkg {
90 struct tb_cfg_header header;
91 struct tb_cfg_address addr;
92} __packed;
93
94/* TB_CFG_PKG_WRITE, response for TB_CFG_PKG_READ */
95struct cfg_write_pkg {
96 struct tb_cfg_header header;
97 struct tb_cfg_address addr;
98 u32 data[64]; /* maximum size, tb_cfg_address.length has 6 bits */
99} __packed;
100
101/* TB_CFG_PKG_ERROR */
102struct cfg_error_pkg {
103 struct tb_cfg_header header;
104 enum tb_cfg_error error:4;
105 u32 zero1:4;
106 u32 port:6;
107 u32 zero2:2; /* Both should be zero, still they are different fields. */
108 u32 zero3:16;
109} __packed;
110
111/* TB_CFG_PKG_EVENT */
112struct cfg_event_pkg {
113 struct tb_cfg_header header;
114 u32 port:6;
115 u32 zero:25;
116 bool unplug:1;
117} __packed;
118
119/* TB_CFG_PKG_RESET */
120struct cfg_reset_pkg {
121 struct tb_cfg_header header;
122} __packed;
123
124/* TB_CFG_PKG_PREPARE_TO_SLEEP */
125struct cfg_pts_pkg {
126 struct tb_cfg_header header;
127 u32 data;
128} __packed;
129
130
131/* utility functions */
132
133static u64 get_route(struct tb_cfg_header header)
134{
135 return (u64) header.route_hi << 32 | header.route_lo;
136}
137
138static struct tb_cfg_header make_header(u64 route)
139{
140 struct tb_cfg_header header = {
141 .route_hi = route >> 32,
142 .route_lo = route,
143 };
144 /* check for overflow, route_hi is not 32 bits! */
145 WARN_ON(get_route(header) != route);
146 return header;
147}
148
149static int check_header(struct ctl_pkg *pkg, u32 len, enum tb_cfg_pkg_type type,
150 u64 route)
151{
152 struct tb_cfg_header *header = pkg->buffer;
153
154 /* check frame, TODO: frame flags */
155 if (WARN(len != pkg->frame.size,
156 "wrong framesize (expected %#x, got %#x)\n",
157 len, pkg->frame.size))
158 return -EIO;
159 if (WARN(type != pkg->frame.eof, "wrong eof (expected %#x, got %#x)\n",
160 type, pkg->frame.eof))
161 return -EIO;
162 if (WARN(pkg->frame.sof, "wrong sof (expected 0x0, got %#x)\n",
163 pkg->frame.sof))
164 return -EIO;
165
166 /* check header */
167 if (WARN(header->unknown != 1 << 9,
168 "header->unknown is %#x\n", header->unknown))
169 return -EIO;
170 if (WARN(route != get_route(*header),
171 "wrong route (expected %llx, got %llx)",
172 route, get_route(*header)))
173 return -EIO;
174 return 0;
175}
176
177static int check_config_address(struct tb_cfg_address addr,
178 enum tb_cfg_space space, u32 offset,
179 u32 length)
180{
181 if (WARN(addr.zero, "addr.zero is %#x\n", addr.zero))
182 return -EIO;
183 if (WARN(space != addr.space, "wrong space (expected %x, got %x\n)",
184 space, addr.space))
185 return -EIO;
186 if (WARN(offset != addr.offset, "wrong offset (expected %x, got %x\n)",
187 offset, addr.offset))
188 return -EIO;
189 if (WARN(length != addr.length, "wrong space (expected %x, got %x\n)",
190 length, addr.length))
191 return -EIO;
192 if (WARN(addr.seq, "addr.seq is %#x\n", addr.seq))
193 return -EIO;
194 /*
195 * We cannot check addr->port as it is set to the upstream port of the
196 * sender.
197 */
198 return 0;
199}
200
201static struct tb_cfg_result decode_error(struct ctl_pkg *response)
202{
203 struct cfg_error_pkg *pkg = response->buffer;
204 struct tb_cfg_result res = { 0 };
205 res.response_route = get_route(pkg->header);
206 res.response_port = 0;
207 res.err = check_header(response, sizeof(*pkg), TB_CFG_PKG_ERROR,
208 get_route(pkg->header));
209 if (res.err)
210 return res;
211
212 WARN(pkg->zero1, "pkg->zero1 is %#x\n", pkg->zero1);
213 WARN(pkg->zero2, "pkg->zero1 is %#x\n", pkg->zero1);
214 WARN(pkg->zero3, "pkg->zero1 is %#x\n", pkg->zero1);
215 res.err = 1;
216 res.tb_error = pkg->error;
217 res.response_port = pkg->port;
218 return res;
219
220}
221
222static struct tb_cfg_result parse_header(struct ctl_pkg *pkg, u32 len,
223 enum tb_cfg_pkg_type type, u64 route)
224{
225 struct tb_cfg_header *header = pkg->buffer;
226 struct tb_cfg_result res = { 0 };
227
228 if (pkg->frame.eof == TB_CFG_PKG_ERROR)
229 return decode_error(pkg);
230
231 res.response_port = 0; /* will be updated later for cfg_read/write */
232 res.response_route = get_route(*header);
233 res.err = check_header(pkg, len, type, route);
234 return res;
235}
236
237static void tb_cfg_print_error(struct tb_ctl *ctl,
238 const struct tb_cfg_result *res)
239{
240 WARN_ON(res->err != 1);
241 switch (res->tb_error) {
242 case TB_CFG_ERROR_PORT_NOT_CONNECTED:
243 /* Port is not connected. This can happen during surprise
244 * removal. Do not warn. */
245 return;
246 case TB_CFG_ERROR_INVALID_CONFIG_SPACE:
247 /*
248 * Invalid cfg_space/offset/length combination in
249 * cfg_read/cfg_write.
250 */
251 tb_ctl_WARN(ctl,
252 "CFG_ERROR(%llx:%x): Invalid config space of offset\n",
253 res->response_route, res->response_port);
254 return;
255 case TB_CFG_ERROR_NO_SUCH_PORT:
256 /*
257 * - The route contains a non-existent port.
258 * - The route contains a non-PHY port (e.g. PCIe).
259 * - The port in cfg_read/cfg_write does not exist.
260 */
261 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Invalid port\n",
262 res->response_route, res->response_port);
263 return;
264 case TB_CFG_ERROR_LOOP:
265 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Route contains a loop\n",
266 res->response_route, res->response_port);
267 return;
268 default:
269 /* 5,6,7,9 and 11 are also valid error codes */
270 tb_ctl_WARN(ctl, "CFG_ERROR(%llx:%x): Unknown error\n",
271 res->response_route, res->response_port);
272 return;
273 }
274}
275
276static void cpu_to_be32_array(__be32 *dst, u32 *src, size_t len)
277{
278 int i;
279 for (i = 0; i < len; i++)
280 dst[i] = cpu_to_be32(src[i]);
281}
282
283static void be32_to_cpu_array(u32 *dst, __be32 *src, size_t len)
284{
285 int i;
286 for (i = 0; i < len; i++)
287 dst[i] = be32_to_cpu(src[i]);
288}
289
290static __be32 tb_crc(void *data, size_t len)
291{
292 return cpu_to_be32(~__crc32c_le(~0, data, len));
293}
294
295static void tb_ctl_pkg_free(struct ctl_pkg *pkg)
296{
297 if (pkg) {
298 dma_pool_free(pkg->ctl->frame_pool,
299 pkg->buffer, pkg->frame.buffer_phy);
300 kfree(pkg);
301 }
302}
303
304static struct ctl_pkg *tb_ctl_pkg_alloc(struct tb_ctl *ctl)
305{
306 struct ctl_pkg *pkg = kzalloc(sizeof(*pkg), GFP_KERNEL);
307 if (!pkg)
Sachin Kamat8db353b2014-06-20 14:32:32 +0530308 return NULL;
Andreas Noeverf25bf6f2014-06-03 22:03:59 +0200309 pkg->ctl = ctl;
310 pkg->buffer = dma_pool_alloc(ctl->frame_pool, GFP_KERNEL,
311 &pkg->frame.buffer_phy);
312 if (!pkg->buffer) {
313 kfree(pkg);
Sachin Kamat8db353b2014-06-20 14:32:32 +0530314 return NULL;
Andreas Noeverf25bf6f2014-06-03 22:03:59 +0200315 }
316 return pkg;
317}
318
319
320/* RX/TX handling */
321
322static void tb_ctl_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
323 bool canceled)
324{
325 struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame);
326 tb_ctl_pkg_free(pkg);
327}
328
329/**
330 * tb_cfg_tx() - transmit a packet on the control channel
331 *
332 * len must be a multiple of four.
333 *
334 * Return: Returns 0 on success or an error code on failure.
335 */
336static int tb_ctl_tx(struct tb_ctl *ctl, void *data, size_t len,
337 enum tb_cfg_pkg_type type)
338{
339 int res;
340 struct ctl_pkg *pkg;
341 if (len % 4 != 0) { /* required for le->be conversion */
342 tb_ctl_WARN(ctl, "TX: invalid size: %zu\n", len);
343 return -EINVAL;
344 }
345 if (len > TB_FRAME_SIZE - 4) { /* checksum is 4 bytes */
346 tb_ctl_WARN(ctl, "TX: packet too large: %zu/%d\n",
347 len, TB_FRAME_SIZE - 4);
348 return -EINVAL;
349 }
350 pkg = tb_ctl_pkg_alloc(ctl);
351 if (!pkg)
352 return -ENOMEM;
353 pkg->frame.callback = tb_ctl_tx_callback;
354 pkg->frame.size = len + 4;
355 pkg->frame.sof = type;
356 pkg->frame.eof = type;
357 cpu_to_be32_array(pkg->buffer, data, len / 4);
Andreas Noever801dba52014-06-20 21:42:22 +0200358 *(__be32 *) (pkg->buffer + len) = tb_crc(pkg->buffer, len);
Andreas Noeverf25bf6f2014-06-03 22:03:59 +0200359
360 res = ring_tx(ctl->tx, &pkg->frame);
361 if (res) /* ring is stopped */
362 tb_ctl_pkg_free(pkg);
363 return res;
364}
365
366/**
367 * tb_ctl_handle_plug_event() - acknowledge a plug event, invoke ctl->callback
368 */
369static void tb_ctl_handle_plug_event(struct tb_ctl *ctl,
370 struct ctl_pkg *response)
371{
372 struct cfg_event_pkg *pkg = response->buffer;
373 u64 route = get_route(pkg->header);
374
375 if (check_header(response, sizeof(*pkg), TB_CFG_PKG_EVENT, route)) {
376 tb_ctl_warn(ctl, "malformed TB_CFG_PKG_EVENT\n");
377 return;
378 }
379
380 if (tb_cfg_error(ctl, route, pkg->port, TB_CFG_ERROR_ACK_PLUG_EVENT))
381 tb_ctl_warn(ctl, "could not ack plug event on %llx:%x\n",
382 route, pkg->port);
383 WARN(pkg->zero, "pkg->zero is %#x\n", pkg->zero);
384 ctl->callback(ctl->callback_data, route, pkg->port, pkg->unplug);
385}
386
387static void tb_ctl_rx_submit(struct ctl_pkg *pkg)
388{
389 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.
394 */
395}
396
397static void tb_ctl_rx_callback(struct tb_ring *ring, struct ring_frame *frame,
398 bool canceled)
399{
400 struct ctl_pkg *pkg = container_of(frame, typeof(*pkg), frame);
401
402 if (canceled)
403 return; /*
404 * ring is stopped, packet is referenced from
405 * ctl->rx_packets.
406 */
407
408 if (frame->size < 4 || frame->size % 4 != 0) {
409 tb_ctl_err(pkg->ctl, "RX: invalid size %#x, dropping packet\n",
410 frame->size);
411 goto rx;
412 }
413
414 frame->size -= 4; /* remove checksum */
Andreas Noever801dba52014-06-20 21:42:22 +0200415 if (*(__be32 *) (pkg->buffer + frame->size)
Andreas Noeverf25bf6f2014-06-03 22:03:59 +0200416 != tb_crc(pkg->buffer, frame->size)) {
417 tb_ctl_err(pkg->ctl,
418 "RX: checksum mismatch, dropping packet\n");
419 goto rx;
420 }
421 be32_to_cpu_array(pkg->buffer, pkg->buffer, frame->size / 4);
422
423 if (frame->eof == TB_CFG_PKG_EVENT) {
424 tb_ctl_handle_plug_event(pkg->ctl, pkg);
425 goto rx;
426 }
427 if (!kfifo_put(&pkg->ctl->response_fifo, pkg)) {
428 tb_ctl_err(pkg->ctl, "RX: fifo is full\n");
429 goto rx;
430 }
431 complete(&pkg->ctl->response_ready);
432 return;
433rx:
434 tb_ctl_rx_submit(pkg);
435}
436
437/**
438 * tb_ctl_rx() - receive a packet from the control channel
439 */
440static struct tb_cfg_result tb_ctl_rx(struct tb_ctl *ctl, void *buffer,
441 size_t length, int timeout_msec,
Andreas Noever343fcb82014-06-12 23:11:47 +0200442 u64 route, enum tb_cfg_pkg_type type)
Andreas Noeverf25bf6f2014-06-03 22:03:59 +0200443{
444 struct tb_cfg_result res;
445 struct ctl_pkg *pkg;
446
447 if (!wait_for_completion_timeout(&ctl->response_ready,
448 msecs_to_jiffies(timeout_msec))) {
449 tb_ctl_WARN(ctl, "RX: timeout\n");
450 return (struct tb_cfg_result) { .err = -ETIMEDOUT };
451 }
452 if (!kfifo_get(&ctl->response_fifo, &pkg)) {
453 tb_ctl_WARN(ctl, "empty kfifo\n");
454 return (struct tb_cfg_result) { .err = -EIO };
455 }
456
457 res = parse_header(pkg, length, type, route);
458 if (!res.err)
459 memcpy(buffer, pkg->buffer, length);
460 tb_ctl_rx_submit(pkg);
461 return res;
462}
463
464
465/* public interface, alloc/start/stop/free */
466
467/**
468 * tb_ctl_alloc() - allocate a control channel
469 *
470 * cb will be invoked once for every hot plug event.
471 *
472 * Return: Returns a pointer on success or NULL on failure.
473 */
474struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, hotplug_cb cb, void *cb_data)
475{
476 int i;
477 struct tb_ctl *ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
478 if (!ctl)
479 return NULL;
480 ctl->nhi = nhi;
481 ctl->callback = cb;
482 ctl->callback_data = cb_data;
483
484 init_completion(&ctl->response_ready);
485 INIT_KFIFO(ctl->response_fifo);
486 ctl->frame_pool = dma_pool_create("thunderbolt_ctl", &nhi->pdev->dev,
487 TB_FRAME_SIZE, 4, 0);
488 if (!ctl->frame_pool)
489 goto err;
490
491 ctl->tx = ring_alloc_tx(nhi, 0, 10);
492 if (!ctl->tx)
493 goto err;
494
495 ctl->rx = ring_alloc_rx(nhi, 0, 10);
496 if (!ctl->rx)
497 goto err;
498
499 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++) {
500 ctl->rx_packets[i] = tb_ctl_pkg_alloc(ctl);
501 if (!ctl->rx_packets[i])
502 goto err;
503 ctl->rx_packets[i]->frame.callback = tb_ctl_rx_callback;
504 }
505
506 tb_ctl_info(ctl, "control channel created\n");
507 return ctl;
508err:
509 tb_ctl_free(ctl);
510 return NULL;
511}
512
513/**
514 * tb_ctl_free() - free a control channel
515 *
516 * Must be called after tb_ctl_stop.
517 *
518 * Must NOT be called from ctl->callback.
519 */
520void tb_ctl_free(struct tb_ctl *ctl)
521{
522 int i;
523 if (ctl->rx)
524 ring_free(ctl->rx);
525 if (ctl->tx)
526 ring_free(ctl->tx);
527
528 /* free RX packets */
529 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
530 tb_ctl_pkg_free(ctl->rx_packets[i]);
531
532
533 if (ctl->frame_pool)
534 dma_pool_destroy(ctl->frame_pool);
535 kfree(ctl);
536}
537
538/**
539 * tb_cfg_start() - start/resume the control channel
540 */
541void tb_ctl_start(struct tb_ctl *ctl)
542{
543 int i;
544 tb_ctl_info(ctl, "control channel starting...\n");
545 ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
546 ring_start(ctl->rx);
547 for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
548 tb_ctl_rx_submit(ctl->rx_packets[i]);
549}
550
551/**
552 * control() - pause the control channel
553 *
554 * All invocations of ctl->callback will have finished after this method
555 * returns.
556 *
557 * Must NOT be called from ctl->callback.
558 */
559void tb_ctl_stop(struct tb_ctl *ctl)
560{
561 ring_stop(ctl->rx);
562 ring_stop(ctl->tx);
563
564 if (!kfifo_is_empty(&ctl->response_fifo))
565 tb_ctl_WARN(ctl, "dangling response in response_fifo\n");
566 kfifo_reset(&ctl->response_fifo);
567 tb_ctl_info(ctl, "control channel stopped\n");
568}
569
570/* public interface, commands */
571
572/**
573 * tb_cfg_error() - send error packet
574 *
575 * Return: Returns 0 on success or an error code on failure.
576 */
577int tb_cfg_error(struct tb_ctl *ctl, u64 route, u32 port,
578 enum tb_cfg_error error)
579{
580 struct cfg_error_pkg pkg = {
581 .header = make_header(route),
582 .port = port,
583 .error = error,
584 };
585 tb_ctl_info(ctl, "resetting error on %llx:%x.\n", route, port);
586 return tb_ctl_tx(ctl, &pkg, sizeof(pkg), TB_CFG_PKG_ERROR);
587}
588
589/**
590 * tb_cfg_reset() - send a reset packet and wait for a response
591 *
592 * If the switch at route is incorrectly configured then we will not receive a
593 * reply (even though the switch will reset). The caller should check for
594 * -ETIMEDOUT and attempt to reconfigure the switch.
595 */
596struct tb_cfg_result tb_cfg_reset(struct tb_ctl *ctl, u64 route,
597 int timeout_msec)
598{
599 int err;
600 struct cfg_reset_pkg request = { .header = make_header(route) };
601 struct tb_cfg_header reply;
602
603 err = tb_ctl_tx(ctl, &request, sizeof(request), TB_CFG_PKG_RESET);
604 if (err)
605 return (struct tb_cfg_result) { .err = err };
606
607 return tb_ctl_rx(ctl, &reply, sizeof(reply), timeout_msec, route,
608 TB_CFG_PKG_RESET);
609}
610
611/**
612 * tb_cfg_read() - read from config space into buffer
613 *
614 * Offset and length are in dwords.
615 */
616struct tb_cfg_result tb_cfg_read_raw(struct tb_ctl *ctl, void *buffer,
617 u64 route, u32 port, enum tb_cfg_space space,
618 u32 offset, u32 length, int timeout_msec)
619{
620 struct tb_cfg_result res = { 0 };
621 struct cfg_read_pkg request = {
622 .header = make_header(route),
623 .addr = {
624 .port = port,
625 .space = space,
626 .offset = offset,
627 .length = length,
628 },
629 };
630 struct cfg_write_pkg reply;
631
632 res.err = tb_ctl_tx(ctl, &request, sizeof(request), TB_CFG_PKG_READ);
633 if (res.err)
634 return res;
635
636 res = tb_ctl_rx(ctl, &reply, 12 + 4 * length, timeout_msec, route,
637 TB_CFG_PKG_READ);
638 if (res.err)
639 return res;
640
641 res.response_port = reply.addr.port;
642 res.err = check_config_address(reply.addr, space, offset, length);
643 if (!res.err)
644 memcpy(buffer, &reply.data, 4 * length);
645 return res;
646}
647
648/**
649 * tb_cfg_write() - write from buffer into config space
650 *
651 * Offset and length are in dwords.
652 */
653struct tb_cfg_result tb_cfg_write_raw(struct tb_ctl *ctl, void *buffer,
654 u64 route, u32 port, enum tb_cfg_space space,
655 u32 offset, u32 length, int timeout_msec)
656{
657 struct tb_cfg_result res = { 0 };
658 struct cfg_write_pkg request = {
659 .header = make_header(route),
660 .addr = {
661 .port = port,
662 .space = space,
663 .offset = offset,
664 .length = length,
665 },
666 };
667 struct cfg_read_pkg reply;
668
669 memcpy(&request.data, buffer, length * 4);
670
671 res.err = tb_ctl_tx(ctl, &request, 12 + 4 * length, TB_CFG_PKG_WRITE);
672 if (res.err)
673 return res;
674
675 res = tb_ctl_rx(ctl, &reply, sizeof(reply), timeout_msec, route,
676 TB_CFG_PKG_WRITE);
677 if (res.err)
678 return res;
679
680 res.response_port = reply.addr.port;
681 res.err = check_config_address(reply.addr, space, offset, length);
682 return res;
683}
684
685int tb_cfg_read(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
686 enum tb_cfg_space space, u32 offset, u32 length)
687{
688 struct tb_cfg_result res = tb_cfg_read_raw(ctl, buffer, route, port,
689 space, offset, length, TB_CFG_DEFAULT_TIMEOUT);
690 if (res.err == 1) {
691 tb_cfg_print_error(ctl, &res);
692 return -EIO;
693 }
694 WARN(res.err, "tb_cfg_read: %d\n", res.err);
695 return res.err;
696}
697
698int tb_cfg_write(struct tb_ctl *ctl, void *buffer, u64 route, u32 port,
699 enum tb_cfg_space space, u32 offset, u32 length)
700{
701 struct tb_cfg_result res = tb_cfg_write_raw(ctl, buffer, route, port,
702 space, offset, length, TB_CFG_DEFAULT_TIMEOUT);
703 if (res.err == 1) {
704 tb_cfg_print_error(ctl, &res);
705 return -EIO;
706 }
707 WARN(res.err, "tb_cfg_write: %d\n", res.err);
708 return res.err;
709}
710
711/**
712 * tb_cfg_get_upstream_port() - get upstream port number of switch at route
713 *
714 * Reads the first dword from the switches TB_CFG_SWITCH config area and
715 * returns the port number from which the reply originated.
716 *
717 * Return: Returns the upstream port number on success or an error code on
718 * failure.
719 */
720int tb_cfg_get_upstream_port(struct tb_ctl *ctl, u64 route)
721{
722 u32 dummy;
723 struct tb_cfg_result res = tb_cfg_read_raw(ctl, &dummy, route, 0,
724 TB_CFG_SWITCH, 0, 1,
725 TB_CFG_DEFAULT_TIMEOUT);
726 if (res.err == 1)
727 return -EIO;
728 if (res.err)
729 return res.err;
730 return res.response_port;
731}