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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Thunderbolt driver - Tunneling support
4 *
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6 * Copyright (C) 2019, Intel Corporation
7 */
8
9#include <linux/delay.h>
10#include <linux/slab.h>
11#include <linux/list.h>
12
13#include "tunnel.h"
14#include "tb.h"
15
16/* PCIe adapters use always HopID of 8 for both directions */
17#define TB_PCI_HOPID 8
18
19#define TB_PCI_PATH_DOWN 0
20#define TB_PCI_PATH_UP 1
21
22/* USB3 adapters use always HopID of 8 for both directions */
23#define TB_USB3_HOPID 8
24
25#define TB_USB3_PATH_DOWN 0
26#define TB_USB3_PATH_UP 1
27
28/* DP adapters use HopID 8 for AUX and 9 for Video */
29#define TB_DP_AUX_TX_HOPID 8
30#define TB_DP_AUX_RX_HOPID 8
31#define TB_DP_VIDEO_HOPID 9
32
33#define TB_DP_VIDEO_PATH_OUT 0
34#define TB_DP_AUX_PATH_OUT 1
35#define TB_DP_AUX_PATH_IN 2
36
37#define TB_DMA_PATH_OUT 0
38#define TB_DMA_PATH_IN 1
39
40static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };
41
42#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...) \
43 do { \
44 struct tb_tunnel *__tunnel = (tunnel); \
45 level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt, \
46 tb_route(__tunnel->src_port->sw), \
47 __tunnel->src_port->port, \
48 tb_route(__tunnel->dst_port->sw), \
49 __tunnel->dst_port->port, \
50 tb_tunnel_names[__tunnel->type], \
51 ## arg); \
52 } while (0)
53
54#define tb_tunnel_WARN(tunnel, fmt, arg...) \
55 __TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
56#define tb_tunnel_warn(tunnel, fmt, arg...) \
57 __TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
58#define tb_tunnel_info(tunnel, fmt, arg...) \
59 __TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
60#define tb_tunnel_dbg(tunnel, fmt, arg...) \
61 __TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
62
63static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
64 enum tb_tunnel_type type)
65{
66 struct tb_tunnel *tunnel;
67
68 tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
69 if (!tunnel)
70 return NULL;
71
72 tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
73 if (!tunnel->paths) {
74 tb_tunnel_free(tunnel);
75 return NULL;
76 }
77
78 INIT_LIST_HEAD(&tunnel->list);
79 tunnel->tb = tb;
80 tunnel->npaths = npaths;
81 tunnel->type = type;
82
83 return tunnel;
84}
85
86static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
87{
88 int res;
89
90 res = tb_pci_port_enable(tunnel->src_port, activate);
91 if (res)
92 return res;
93
94 if (tb_port_is_pcie_up(tunnel->dst_port))
95 return tb_pci_port_enable(tunnel->dst_port, activate);
96
97 return 0;
98}
99
100static int tb_initial_credits(const struct tb_switch *sw)
101{
102 /* If the path is complete sw is not NULL */
103 if (sw) {
104 /* More credits for faster link */
105 switch (sw->link_speed * sw->link_width) {
106 case 40:
107 return 32;
108 case 20:
109 return 24;
110 }
111 }
112
113 return 16;
114}
115
116static void tb_pci_init_path(struct tb_path *path)
117{
118 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
119 path->egress_shared_buffer = TB_PATH_NONE;
120 path->ingress_fc_enable = TB_PATH_ALL;
121 path->ingress_shared_buffer = TB_PATH_NONE;
122 path->priority = 3;
123 path->weight = 1;
124 path->drop_packages = 0;
125 path->nfc_credits = 0;
126 path->hops[0].initial_credits = 7;
127 if (path->path_length > 1)
128 path->hops[1].initial_credits =
129 tb_initial_credits(path->hops[1].in_port->sw);
130}
131
132/**
133 * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
134 * @tb: Pointer to the domain structure
135 * @down: PCIe downstream adapter
136 *
137 * If @down adapter is active, follows the tunnel to the PCIe upstream
138 * adapter and back. Returns the discovered tunnel or %NULL if there was
139 * no tunnel.
140 */
141struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
142{
143 struct tb_tunnel *tunnel;
144 struct tb_path *path;
145
146 if (!tb_pci_port_is_enabled(down))
147 return NULL;
148
149 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
150 if (!tunnel)
151 return NULL;
152
153 tunnel->activate = tb_pci_activate;
154 tunnel->src_port = down;
155
156 /*
157 * Discover both paths even if they are not complete. We will
158 * clean them up by calling tb_tunnel_deactivate() below in that
159 * case.
160 */
161 path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
162 &tunnel->dst_port, "PCIe Up");
163 if (!path) {
164 /* Just disable the downstream port */
165 tb_pci_port_enable(down, false);
166 goto err_free;
167 }
168 tunnel->paths[TB_PCI_PATH_UP] = path;
169 tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]);
170
171 path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
172 "PCIe Down");
173 if (!path)
174 goto err_deactivate;
175 tunnel->paths[TB_PCI_PATH_DOWN] = path;
176 tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]);
177
178 /* Validate that the tunnel is complete */
179 if (!tb_port_is_pcie_up(tunnel->dst_port)) {
180 tb_port_warn(tunnel->dst_port,
181 "path does not end on a PCIe adapter, cleaning up\n");
182 goto err_deactivate;
183 }
184
185 if (down != tunnel->src_port) {
186 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
187 goto err_deactivate;
188 }
189
190 if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
191 tb_tunnel_warn(tunnel,
192 "tunnel is not fully activated, cleaning up\n");
193 goto err_deactivate;
194 }
195
196 tb_tunnel_dbg(tunnel, "discovered\n");
197 return tunnel;
198
199err_deactivate:
200 tb_tunnel_deactivate(tunnel);
201err_free:
202 tb_tunnel_free(tunnel);
203
204 return NULL;
205}
206
207/**
208 * tb_tunnel_alloc_pci() - allocate a pci tunnel
209 * @tb: Pointer to the domain structure
210 * @up: PCIe upstream adapter port
211 * @down: PCIe downstream adapter port
212 *
213 * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
214 * TB_TYPE_PCIE_DOWN.
215 *
216 * Return: Returns a tb_tunnel on success or NULL on failure.
217 */
218struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
219 struct tb_port *down)
220{
221 struct tb_tunnel *tunnel;
222 struct tb_path *path;
223
224 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
225 if (!tunnel)
226 return NULL;
227
228 tunnel->activate = tb_pci_activate;
229 tunnel->src_port = down;
230 tunnel->dst_port = up;
231
232 path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
233 "PCIe Down");
234 if (!path) {
235 tb_tunnel_free(tunnel);
236 return NULL;
237 }
238 tb_pci_init_path(path);
239 tunnel->paths[TB_PCI_PATH_DOWN] = path;
240
241 path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
242 "PCIe Up");
243 if (!path) {
244 tb_tunnel_free(tunnel);
245 return NULL;
246 }
247 tb_pci_init_path(path);
248 tunnel->paths[TB_PCI_PATH_UP] = path;
249
250 return tunnel;
251}
252
253static bool tb_dp_is_usb4(const struct tb_switch *sw)
254{
255 /* Titan Ridge DP adapters need the same treatment as USB4 */
256 return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
257}
258
259static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
260{
261 int timeout = 10;
262 u32 val;
263 int ret;
264
265 /* Both ends need to support this */
266 if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
267 return 0;
268
269 ret = tb_port_read(out, &val, TB_CFG_PORT,
270 out->cap_adap + DP_STATUS_CTRL, 1);
271 if (ret)
272 return ret;
273
274 val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;
275
276 ret = tb_port_write(out, &val, TB_CFG_PORT,
277 out->cap_adap + DP_STATUS_CTRL, 1);
278 if (ret)
279 return ret;
280
281 do {
282 ret = tb_port_read(out, &val, TB_CFG_PORT,
283 out->cap_adap + DP_STATUS_CTRL, 1);
284 if (ret)
285 return ret;
286 if (!(val & DP_STATUS_CTRL_CMHS))
287 return 0;
288 usleep_range(10, 100);
289 } while (timeout--);
290
291 return -ETIMEDOUT;
292}
293
294static inline u32 tb_dp_cap_get_rate(u32 val)
295{
296 u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;
297
298 switch (rate) {
299 case DP_COMMON_CAP_RATE_RBR:
300 return 1620;
301 case DP_COMMON_CAP_RATE_HBR:
302 return 2700;
303 case DP_COMMON_CAP_RATE_HBR2:
304 return 5400;
305 case DP_COMMON_CAP_RATE_HBR3:
306 return 8100;
307 default:
308 return 0;
309 }
310}
311
312static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
313{
314 val &= ~DP_COMMON_CAP_RATE_MASK;
315 switch (rate) {
316 default:
317 WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
318 fallthrough;
319 case 1620:
320 val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
321 break;
322 case 2700:
323 val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
324 break;
325 case 5400:
326 val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
327 break;
328 case 8100:
329 val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
330 break;
331 }
332 return val;
333}
334
335static inline u32 tb_dp_cap_get_lanes(u32 val)
336{
337 u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;
338
339 switch (lanes) {
340 case DP_COMMON_CAP_1_LANE:
341 return 1;
342 case DP_COMMON_CAP_2_LANES:
343 return 2;
344 case DP_COMMON_CAP_4_LANES:
345 return 4;
346 default:
347 return 0;
348 }
349}
350
351static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
352{
353 val &= ~DP_COMMON_CAP_LANES_MASK;
354 switch (lanes) {
355 default:
356 WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
357 lanes);
358 fallthrough;
359 case 1:
360 val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
361 break;
362 case 2:
363 val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
364 break;
365 case 4:
366 val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
367 break;
368 }
369 return val;
370}
371
372static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
373{
374 /* Tunneling removes the DP 8b/10b encoding */
375 return rate * lanes * 8 / 10;
376}
377
378static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes,
379 u32 out_rate, u32 out_lanes, u32 *new_rate,
380 u32 *new_lanes)
381{
382 static const u32 dp_bw[][2] = {
383 /* Mb/s, lanes */
384 { 8100, 4 }, /* 25920 Mb/s */
385 { 5400, 4 }, /* 17280 Mb/s */
386 { 8100, 2 }, /* 12960 Mb/s */
387 { 2700, 4 }, /* 8640 Mb/s */
388 { 5400, 2 }, /* 8640 Mb/s */
389 { 8100, 1 }, /* 6480 Mb/s */
390 { 1620, 4 }, /* 5184 Mb/s */
391 { 5400, 1 }, /* 4320 Mb/s */
392 { 2700, 2 }, /* 4320 Mb/s */
393 { 1620, 2 }, /* 2592 Mb/s */
394 { 2700, 1 }, /* 2160 Mb/s */
395 { 1620, 1 }, /* 1296 Mb/s */
396 };
397 unsigned int i;
398
399 /*
400 * Find a combination that can fit into max_bw and does not
401 * exceed the maximum rate and lanes supported by the DP OUT and
402 * DP IN adapters.
403 */
404 for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
405 if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
406 continue;
407
408 if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
409 continue;
410
411 if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
412 *new_rate = dp_bw[i][0];
413 *new_lanes = dp_bw[i][1];
414 return 0;
415 }
416 }
417
418 return -ENOSR;
419}
420
421static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
422{
423 u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
424 struct tb_port *out = tunnel->dst_port;
425 struct tb_port *in = tunnel->src_port;
426 int ret, max_bw;
427
428 /*
429 * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
430 * newer generation hardware.
431 */
432 if (in->sw->generation < 2 || out->sw->generation < 2)
433 return 0;
434
435 /*
436 * Perform connection manager handshake between IN and OUT ports
437 * before capabilities exchange can take place.
438 */
439 ret = tb_dp_cm_handshake(in, out);
440 if (ret)
441 return ret;
442
443 /* Read both DP_LOCAL_CAP registers */
444 ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
445 in->cap_adap + DP_LOCAL_CAP, 1);
446 if (ret)
447 return ret;
448
449 ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
450 out->cap_adap + DP_LOCAL_CAP, 1);
451 if (ret)
452 return ret;
453
454 /* Write IN local caps to OUT remote caps */
455 ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
456 out->cap_adap + DP_REMOTE_CAP, 1);
457 if (ret)
458 return ret;
459
460 in_rate = tb_dp_cap_get_rate(in_dp_cap);
461 in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
462 tb_port_dbg(in, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
463 in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));
464
465 /*
466 * If the tunnel bandwidth is limited (max_bw is set) then see
467 * if we need to reduce bandwidth to fit there.
468 */
469 out_rate = tb_dp_cap_get_rate(out_dp_cap);
470 out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
471 bw = tb_dp_bandwidth(out_rate, out_lanes);
472 tb_port_dbg(out, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
473 out_rate, out_lanes, bw);
474
475 if (in->sw->config.depth < out->sw->config.depth)
476 max_bw = tunnel->max_down;
477 else
478 max_bw = tunnel->max_up;
479
480 if (max_bw && bw > max_bw) {
481 u32 new_rate, new_lanes, new_bw;
482
483 ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes,
484 out_rate, out_lanes, &new_rate,
485 &new_lanes);
486 if (ret) {
487 tb_port_info(out, "not enough bandwidth for DP tunnel\n");
488 return ret;
489 }
490
491 new_bw = tb_dp_bandwidth(new_rate, new_lanes);
492 tb_port_dbg(out, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
493 new_rate, new_lanes, new_bw);
494
495 /*
496 * Set new rate and number of lanes before writing it to
497 * the IN port remote caps.
498 */
499 out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
500 out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
501 }
502
503 return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
504 in->cap_adap + DP_REMOTE_CAP, 1);
505}
506
507static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
508{
509 int ret;
510
511 if (active) {
512 struct tb_path **paths;
513 int last;
514
515 paths = tunnel->paths;
516 last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
517
518 tb_dp_port_set_hops(tunnel->src_port,
519 paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
520 paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
521 paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
522
523 tb_dp_port_set_hops(tunnel->dst_port,
524 paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
525 paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
526 paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
527 } else {
528 tb_dp_port_hpd_clear(tunnel->src_port);
529 tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
530 if (tb_port_is_dpout(tunnel->dst_port))
531 tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
532 }
533
534 ret = tb_dp_port_enable(tunnel->src_port, active);
535 if (ret)
536 return ret;
537
538 if (tb_port_is_dpout(tunnel->dst_port))
539 return tb_dp_port_enable(tunnel->dst_port, active);
540
541 return 0;
542}
543
544static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
545 int *consumed_down)
546{
547 struct tb_port *in = tunnel->src_port;
548 const struct tb_switch *sw = in->sw;
549 u32 val, rate = 0, lanes = 0;
550 int ret;
551
552 if (tb_dp_is_usb4(sw)) {
553 int timeout = 20;
554
555 /*
556 * Wait for DPRX done. Normally it should be already set
557 * for active tunnel.
558 */
559 do {
560 ret = tb_port_read(in, &val, TB_CFG_PORT,
561 in->cap_adap + DP_COMMON_CAP, 1);
562 if (ret)
563 return ret;
564
565 if (val & DP_COMMON_CAP_DPRX_DONE) {
566 rate = tb_dp_cap_get_rate(val);
567 lanes = tb_dp_cap_get_lanes(val);
568 break;
569 }
570 msleep(250);
571 } while (timeout--);
572
573 if (!timeout)
574 return -ETIMEDOUT;
575 } else if (sw->generation >= 2) {
576 /*
577 * Read from the copied remote cap so that we take into
578 * account if capabilities were reduced during exchange.
579 */
580 ret = tb_port_read(in, &val, TB_CFG_PORT,
581 in->cap_adap + DP_REMOTE_CAP, 1);
582 if (ret)
583 return ret;
584
585 rate = tb_dp_cap_get_rate(val);
586 lanes = tb_dp_cap_get_lanes(val);
587 } else {
588 /* No bandwidth management for legacy devices */
589 *consumed_up = 0;
590 *consumed_down = 0;
591 return 0;
592 }
593
594 if (in->sw->config.depth < tunnel->dst_port->sw->config.depth) {
595 *consumed_up = 0;
596 *consumed_down = tb_dp_bandwidth(rate, lanes);
597 } else {
598 *consumed_up = tb_dp_bandwidth(rate, lanes);
599 *consumed_down = 0;
600 }
601
602 return 0;
603}
604
605static void tb_dp_init_aux_path(struct tb_path *path)
606{
607 int i;
608
609 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
610 path->egress_shared_buffer = TB_PATH_NONE;
611 path->ingress_fc_enable = TB_PATH_ALL;
612 path->ingress_shared_buffer = TB_PATH_NONE;
613 path->priority = 2;
614 path->weight = 1;
615
616 for (i = 0; i < path->path_length; i++)
617 path->hops[i].initial_credits = 1;
618}
619
620static void tb_dp_init_video_path(struct tb_path *path, bool discover)
621{
622 u32 nfc_credits = path->hops[0].in_port->config.nfc_credits;
623
624 path->egress_fc_enable = TB_PATH_NONE;
625 path->egress_shared_buffer = TB_PATH_NONE;
626 path->ingress_fc_enable = TB_PATH_NONE;
627 path->ingress_shared_buffer = TB_PATH_NONE;
628 path->priority = 1;
629 path->weight = 1;
630
631 if (discover) {
632 path->nfc_credits = nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
633 } else {
634 u32 max_credits;
635
636 max_credits = (nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
637 ADP_CS_4_TOTAL_BUFFERS_SHIFT;
638 /* Leave some credits for AUX path */
639 path->nfc_credits = min(max_credits - 2, 12U);
640 }
641}
642
643/**
644 * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
645 * @tb: Pointer to the domain structure
646 * @in: DP in adapter
647 *
648 * If @in adapter is active, follows the tunnel to the DP out adapter
649 * and back. Returns the discovered tunnel or %NULL if there was no
650 * tunnel.
651 *
652 * Return: DP tunnel or %NULL if no tunnel found.
653 */
654struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
655{
656 struct tb_tunnel *tunnel;
657 struct tb_port *port;
658 struct tb_path *path;
659
660 if (!tb_dp_port_is_enabled(in))
661 return NULL;
662
663 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
664 if (!tunnel)
665 return NULL;
666
667 tunnel->init = tb_dp_xchg_caps;
668 tunnel->activate = tb_dp_activate;
669 tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
670 tunnel->src_port = in;
671
672 path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
673 &tunnel->dst_port, "Video");
674 if (!path) {
675 /* Just disable the DP IN port */
676 tb_dp_port_enable(in, false);
677 goto err_free;
678 }
679 tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
680 tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], true);
681
682 path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
683 if (!path)
684 goto err_deactivate;
685 tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
686 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
687
688 path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
689 &port, "AUX RX");
690 if (!path)
691 goto err_deactivate;
692 tunnel->paths[TB_DP_AUX_PATH_IN] = path;
693 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);
694
695 /* Validate that the tunnel is complete */
696 if (!tb_port_is_dpout(tunnel->dst_port)) {
697 tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
698 goto err_deactivate;
699 }
700
701 if (!tb_dp_port_is_enabled(tunnel->dst_port))
702 goto err_deactivate;
703
704 if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
705 goto err_deactivate;
706
707 if (port != tunnel->src_port) {
708 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
709 goto err_deactivate;
710 }
711
712 tb_tunnel_dbg(tunnel, "discovered\n");
713 return tunnel;
714
715err_deactivate:
716 tb_tunnel_deactivate(tunnel);
717err_free:
718 tb_tunnel_free(tunnel);
719
720 return NULL;
721}
722
723/**
724 * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
725 * @tb: Pointer to the domain structure
726 * @in: DP in adapter port
727 * @out: DP out adapter port
728 * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0
729 * if not limited)
730 * @max_down: Maximum available downstream bandwidth for the DP tunnel
731 * (%0 if not limited)
732 *
733 * Allocates a tunnel between @in and @out that is capable of tunneling
734 * Display Port traffic.
735 *
736 * Return: Returns a tb_tunnel on success or NULL on failure.
737 */
738struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
739 struct tb_port *out, int max_up,
740 int max_down)
741{
742 struct tb_tunnel *tunnel;
743 struct tb_path **paths;
744 struct tb_path *path;
745
746 if (WARN_ON(!in->cap_adap || !out->cap_adap))
747 return NULL;
748
749 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
750 if (!tunnel)
751 return NULL;
752
753 tunnel->init = tb_dp_xchg_caps;
754 tunnel->activate = tb_dp_activate;
755 tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
756 tunnel->src_port = in;
757 tunnel->dst_port = out;
758 tunnel->max_up = max_up;
759 tunnel->max_down = max_down;
760
761 paths = tunnel->paths;
762
763 path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
764 1, "Video");
765 if (!path)
766 goto err_free;
767 tb_dp_init_video_path(path, false);
768 paths[TB_DP_VIDEO_PATH_OUT] = path;
769
770 path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
771 TB_DP_AUX_TX_HOPID, 1, "AUX TX");
772 if (!path)
773 goto err_free;
774 tb_dp_init_aux_path(path);
775 paths[TB_DP_AUX_PATH_OUT] = path;
776
777 path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
778 TB_DP_AUX_RX_HOPID, 1, "AUX RX");
779 if (!path)
780 goto err_free;
781 tb_dp_init_aux_path(path);
782 paths[TB_DP_AUX_PATH_IN] = path;
783
784 return tunnel;
785
786err_free:
787 tb_tunnel_free(tunnel);
788 return NULL;
789}
790
791static u32 tb_dma_credits(struct tb_port *nhi)
792{
793 u32 max_credits;
794
795 max_credits = (nhi->config.nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
796 ADP_CS_4_TOTAL_BUFFERS_SHIFT;
797 return min(max_credits, 13U);
798}
799
800static int tb_dma_activate(struct tb_tunnel *tunnel, bool active)
801{
802 struct tb_port *nhi = tunnel->src_port;
803 u32 credits;
804
805 credits = active ? tb_dma_credits(nhi) : 0;
806 return tb_port_set_initial_credits(nhi, credits);
807}
808
809static void tb_dma_init_path(struct tb_path *path, unsigned int isb,
810 unsigned int efc, u32 credits)
811{
812 int i;
813
814 path->egress_fc_enable = efc;
815 path->ingress_fc_enable = TB_PATH_ALL;
816 path->egress_shared_buffer = TB_PATH_NONE;
817 path->ingress_shared_buffer = isb;
818 path->priority = 5;
819 path->weight = 1;
820 path->clear_fc = true;
821
822 for (i = 0; i < path->path_length; i++)
823 path->hops[i].initial_credits = credits;
824}
825
826/**
827 * tb_tunnel_alloc_dma() - allocate a DMA tunnel
828 * @tb: Pointer to the domain structure
829 * @nhi: Host controller port
830 * @dst: Destination null port which the other domain is connected to
831 * @transmit_ring: NHI ring number used to send packets towards the
832 * other domain
833 * @transmit_path: HopID used for transmitting packets
834 * @receive_ring: NHI ring number used to receive packets from the
835 * other domain
836 * @reveive_path: HopID used for receiving packets
837 *
838 * Return: Returns a tb_tunnel on success or NULL on failure.
839 */
840struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
841 struct tb_port *dst, int transmit_ring,
842 int transmit_path, int receive_ring,
843 int receive_path)
844{
845 struct tb_tunnel *tunnel;
846 struct tb_path *path;
847 u32 credits;
848
849 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);
850 if (!tunnel)
851 return NULL;
852
853 tunnel->activate = tb_dma_activate;
854 tunnel->src_port = nhi;
855 tunnel->dst_port = dst;
856
857 credits = tb_dma_credits(nhi);
858
859 path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX");
860 if (!path) {
861 tb_tunnel_free(tunnel);
862 return NULL;
863 }
864 tb_dma_init_path(path, TB_PATH_NONE, TB_PATH_SOURCE | TB_PATH_INTERNAL,
865 credits);
866 tunnel->paths[TB_DMA_PATH_IN] = path;
867
868 path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX");
869 if (!path) {
870 tb_tunnel_free(tunnel);
871 return NULL;
872 }
873 tb_dma_init_path(path, TB_PATH_SOURCE, TB_PATH_ALL, credits);
874 tunnel->paths[TB_DMA_PATH_OUT] = path;
875
876 return tunnel;
877}
878
879static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down)
880{
881 int ret, up_max_rate, down_max_rate;
882
883 ret = usb4_usb3_port_max_link_rate(up);
884 if (ret < 0)
885 return ret;
886 up_max_rate = ret;
887
888 ret = usb4_usb3_port_max_link_rate(down);
889 if (ret < 0)
890 return ret;
891 down_max_rate = ret;
892
893 return min(up_max_rate, down_max_rate);
894}
895
896static int tb_usb3_init(struct tb_tunnel *tunnel)
897{
898 tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n",
899 tunnel->allocated_up, tunnel->allocated_down);
900
901 return usb4_usb3_port_allocate_bandwidth(tunnel->src_port,
902 &tunnel->allocated_up,
903 &tunnel->allocated_down);
904}
905
906static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate)
907{
908 int res;
909
910 res = tb_usb3_port_enable(tunnel->src_port, activate);
911 if (res)
912 return res;
913
914 if (tb_port_is_usb3_up(tunnel->dst_port))
915 return tb_usb3_port_enable(tunnel->dst_port, activate);
916
917 return 0;
918}
919
920static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel,
921 int *consumed_up, int *consumed_down)
922{
923 /*
924 * PCIe tunneling affects the USB3 bandwidth so take that it
925 * into account here.
926 */
927 *consumed_up = tunnel->allocated_up * (3 + 1) / 3;
928 *consumed_down = tunnel->allocated_down * (3 + 1) / 3;
929 return 0;
930}
931
932static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel)
933{
934 int ret;
935
936 ret = usb4_usb3_port_release_bandwidth(tunnel->src_port,
937 &tunnel->allocated_up,
938 &tunnel->allocated_down);
939 if (ret)
940 return ret;
941
942 tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n",
943 tunnel->allocated_up, tunnel->allocated_down);
944 return 0;
945}
946
947static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
948 int *available_up,
949 int *available_down)
950{
951 int ret, max_rate, allocate_up, allocate_down;
952
953 ret = usb4_usb3_port_actual_link_rate(tunnel->src_port);
954 if (ret < 0) {
955 tb_tunnel_warn(tunnel, "failed to read actual link rate\n");
956 return;
957 } else if (!ret) {
958 /* Use maximum link rate if the link valid is not set */
959 ret = usb4_usb3_port_max_link_rate(tunnel->src_port);
960 if (ret < 0) {
961 tb_tunnel_warn(tunnel, "failed to read maximum link rate\n");
962 return;
963 }
964 }
965
966 /*
967 * 90% of the max rate can be allocated for isochronous
968 * transfers.
969 */
970 max_rate = ret * 90 / 100;
971
972 /* No need to reclaim if already at maximum */
973 if (tunnel->allocated_up >= max_rate &&
974 tunnel->allocated_down >= max_rate)
975 return;
976
977 /* Don't go lower than what is already allocated */
978 allocate_up = min(max_rate, *available_up);
979 if (allocate_up < tunnel->allocated_up)
980 allocate_up = tunnel->allocated_up;
981
982 allocate_down = min(max_rate, *available_down);
983 if (allocate_down < tunnel->allocated_down)
984 allocate_down = tunnel->allocated_down;
985
986 /* If no changes no need to do more */
987 if (allocate_up == tunnel->allocated_up &&
988 allocate_down == tunnel->allocated_down)
989 return;
990
991 ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up,
992 &allocate_down);
993 if (ret) {
994 tb_tunnel_info(tunnel, "failed to allocate bandwidth\n");
995 return;
996 }
997
998 tunnel->allocated_up = allocate_up;
999 *available_up -= tunnel->allocated_up;
1000
1001 tunnel->allocated_down = allocate_down;
1002 *available_down -= tunnel->allocated_down;
1003
1004 tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n",
1005 tunnel->allocated_up, tunnel->allocated_down);
1006}
1007
1008static void tb_usb3_init_path(struct tb_path *path)
1009{
1010 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1011 path->egress_shared_buffer = TB_PATH_NONE;
1012 path->ingress_fc_enable = TB_PATH_ALL;
1013 path->ingress_shared_buffer = TB_PATH_NONE;
1014 path->priority = 3;
1015 path->weight = 3;
1016 path->drop_packages = 0;
1017 path->nfc_credits = 0;
1018 path->hops[0].initial_credits = 7;
1019 if (path->path_length > 1)
1020 path->hops[1].initial_credits =
1021 tb_initial_credits(path->hops[1].in_port->sw);
1022}
1023
1024/**
1025 * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
1026 * @tb: Pointer to the domain structure
1027 * @down: USB3 downstream adapter
1028 *
1029 * If @down adapter is active, follows the tunnel to the USB3 upstream
1030 * adapter and back. Returns the discovered tunnel or %NULL if there was
1031 * no tunnel.
1032 */
1033struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
1034{
1035 struct tb_tunnel *tunnel;
1036 struct tb_path *path;
1037
1038 if (!tb_usb3_port_is_enabled(down))
1039 return NULL;
1040
1041 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1042 if (!tunnel)
1043 return NULL;
1044
1045 tunnel->activate = tb_usb3_activate;
1046 tunnel->src_port = down;
1047
1048 /*
1049 * Discover both paths even if they are not complete. We will
1050 * clean them up by calling tb_tunnel_deactivate() below in that
1051 * case.
1052 */
1053 path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
1054 &tunnel->dst_port, "USB3 Down");
1055 if (!path) {
1056 /* Just disable the downstream port */
1057 tb_usb3_port_enable(down, false);
1058 goto err_free;
1059 }
1060 tunnel->paths[TB_USB3_PATH_DOWN] = path;
1061 tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
1062
1063 path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
1064 "USB3 Up");
1065 if (!path)
1066 goto err_deactivate;
1067 tunnel->paths[TB_USB3_PATH_UP] = path;
1068 tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]);
1069
1070 /* Validate that the tunnel is complete */
1071 if (!tb_port_is_usb3_up(tunnel->dst_port)) {
1072 tb_port_warn(tunnel->dst_port,
1073 "path does not end on an USB3 adapter, cleaning up\n");
1074 goto err_deactivate;
1075 }
1076
1077 if (down != tunnel->src_port) {
1078 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
1079 goto err_deactivate;
1080 }
1081
1082 if (!tb_usb3_port_is_enabled(tunnel->dst_port)) {
1083 tb_tunnel_warn(tunnel,
1084 "tunnel is not fully activated, cleaning up\n");
1085 goto err_deactivate;
1086 }
1087
1088 if (!tb_route(down->sw)) {
1089 int ret;
1090
1091 /*
1092 * Read the initial bandwidth allocation for the first
1093 * hop tunnel.
1094 */
1095 ret = usb4_usb3_port_allocated_bandwidth(down,
1096 &tunnel->allocated_up, &tunnel->allocated_down);
1097 if (ret)
1098 goto err_deactivate;
1099
1100 tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n",
1101 tunnel->allocated_up, tunnel->allocated_down);
1102
1103 tunnel->init = tb_usb3_init;
1104 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1105 tunnel->release_unused_bandwidth =
1106 tb_usb3_release_unused_bandwidth;
1107 tunnel->reclaim_available_bandwidth =
1108 tb_usb3_reclaim_available_bandwidth;
1109 }
1110
1111 tb_tunnel_dbg(tunnel, "discovered\n");
1112 return tunnel;
1113
1114err_deactivate:
1115 tb_tunnel_deactivate(tunnel);
1116err_free:
1117 tb_tunnel_free(tunnel);
1118
1119 return NULL;
1120}
1121
1122/**
1123 * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel
1124 * @tb: Pointer to the domain structure
1125 * @up: USB3 upstream adapter port
1126 * @down: USB3 downstream adapter port
1127 * @max_up: Maximum available upstream bandwidth for the USB3 tunnel (%0
1128 * if not limited).
1129 * @max_down: Maximum available downstream bandwidth for the USB3 tunnel
1130 * (%0 if not limited).
1131 *
1132 * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and
1133 * @TB_TYPE_USB3_DOWN.
1134 *
1135 * Return: Returns a tb_tunnel on success or %NULL on failure.
1136 */
1137struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
1138 struct tb_port *down, int max_up,
1139 int max_down)
1140{
1141 struct tb_tunnel *tunnel;
1142 struct tb_path *path;
1143 int max_rate = 0;
1144
1145 /*
1146 * Check that we have enough bandwidth available for the new
1147 * USB3 tunnel.
1148 */
1149 if (max_up > 0 || max_down > 0) {
1150 max_rate = tb_usb3_max_link_rate(down, up);
1151 if (max_rate < 0)
1152 return NULL;
1153
1154 /* Only 90% can be allocated for USB3 isochronous transfers */
1155 max_rate = max_rate * 90 / 100;
1156 tb_port_dbg(up, "required bandwidth for USB3 tunnel %d Mb/s\n",
1157 max_rate);
1158
1159 if (max_rate > max_up || max_rate > max_down) {
1160 tb_port_warn(up, "not enough bandwidth for USB3 tunnel\n");
1161 return NULL;
1162 }
1163 }
1164
1165 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1166 if (!tunnel)
1167 return NULL;
1168
1169 tunnel->activate = tb_usb3_activate;
1170 tunnel->src_port = down;
1171 tunnel->dst_port = up;
1172 tunnel->max_up = max_up;
1173 tunnel->max_down = max_down;
1174
1175 path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0,
1176 "USB3 Down");
1177 if (!path) {
1178 tb_tunnel_free(tunnel);
1179 return NULL;
1180 }
1181 tb_usb3_init_path(path);
1182 tunnel->paths[TB_USB3_PATH_DOWN] = path;
1183
1184 path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0,
1185 "USB3 Up");
1186 if (!path) {
1187 tb_tunnel_free(tunnel);
1188 return NULL;
1189 }
1190 tb_usb3_init_path(path);
1191 tunnel->paths[TB_USB3_PATH_UP] = path;
1192
1193 if (!tb_route(down->sw)) {
1194 tunnel->allocated_up = max_rate;
1195 tunnel->allocated_down = max_rate;
1196
1197 tunnel->init = tb_usb3_init;
1198 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1199 tunnel->release_unused_bandwidth =
1200 tb_usb3_release_unused_bandwidth;
1201 tunnel->reclaim_available_bandwidth =
1202 tb_usb3_reclaim_available_bandwidth;
1203 }
1204
1205 return tunnel;
1206}
1207
1208/**
1209 * tb_tunnel_free() - free a tunnel
1210 * @tunnel: Tunnel to be freed
1211 *
1212 * Frees a tunnel. The tunnel does not need to be deactivated.
1213 */
1214void tb_tunnel_free(struct tb_tunnel *tunnel)
1215{
1216 int i;
1217
1218 if (!tunnel)
1219 return;
1220
1221 for (i = 0; i < tunnel->npaths; i++) {
1222 if (tunnel->paths[i])
1223 tb_path_free(tunnel->paths[i]);
1224 }
1225
1226 kfree(tunnel->paths);
1227 kfree(tunnel);
1228}
1229
1230/**
1231 * tb_tunnel_is_invalid - check whether an activated path is still valid
1232 * @tunnel: Tunnel to check
1233 */
1234bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
1235{
1236 int i;
1237
1238 for (i = 0; i < tunnel->npaths; i++) {
1239 WARN_ON(!tunnel->paths[i]->activated);
1240 if (tb_path_is_invalid(tunnel->paths[i]))
1241 return true;
1242 }
1243
1244 return false;
1245}
1246
1247/**
1248 * tb_tunnel_restart() - activate a tunnel after a hardware reset
1249 * @tunnel: Tunnel to restart
1250 *
1251 * Return: 0 on success and negative errno in case if failure
1252 */
1253int tb_tunnel_restart(struct tb_tunnel *tunnel)
1254{
1255 int res, i;
1256
1257 tb_tunnel_dbg(tunnel, "activating\n");
1258
1259 /*
1260 * Make sure all paths are properly disabled before enabling
1261 * them again.
1262 */
1263 for (i = 0; i < tunnel->npaths; i++) {
1264 if (tunnel->paths[i]->activated) {
1265 tb_path_deactivate(tunnel->paths[i]);
1266 tunnel->paths[i]->activated = false;
1267 }
1268 }
1269
1270 if (tunnel->init) {
1271 res = tunnel->init(tunnel);
1272 if (res)
1273 return res;
1274 }
1275
1276 for (i = 0; i < tunnel->npaths; i++) {
1277 res = tb_path_activate(tunnel->paths[i]);
1278 if (res)
1279 goto err;
1280 }
1281
1282 if (tunnel->activate) {
1283 res = tunnel->activate(tunnel, true);
1284 if (res)
1285 goto err;
1286 }
1287
1288 return 0;
1289
1290err:
1291 tb_tunnel_warn(tunnel, "activation failed\n");
1292 tb_tunnel_deactivate(tunnel);
1293 return res;
1294}
1295
1296/**
1297 * tb_tunnel_activate() - activate a tunnel
1298 * @tunnel: Tunnel to activate
1299 *
1300 * Return: Returns 0 on success or an error code on failure.
1301 */
1302int tb_tunnel_activate(struct tb_tunnel *tunnel)
1303{
1304 int i;
1305
1306 for (i = 0; i < tunnel->npaths; i++) {
1307 if (tunnel->paths[i]->activated) {
1308 tb_tunnel_WARN(tunnel,
1309 "trying to activate an already activated tunnel\n");
1310 return -EINVAL;
1311 }
1312 }
1313
1314 return tb_tunnel_restart(tunnel);
1315}
1316
1317/**
1318 * tb_tunnel_deactivate() - deactivate a tunnel
1319 * @tunnel: Tunnel to deactivate
1320 */
1321void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
1322{
1323 int i;
1324
1325 tb_tunnel_dbg(tunnel, "deactivating\n");
1326
1327 if (tunnel->activate)
1328 tunnel->activate(tunnel, false);
1329
1330 for (i = 0; i < tunnel->npaths; i++) {
1331 if (tunnel->paths[i] && tunnel->paths[i]->activated)
1332 tb_path_deactivate(tunnel->paths[i]);
1333 }
1334}
1335
1336/**
1337 * tb_tunnel_port_on_path() - Does the tunnel go through port
1338 * @tunnel: Tunnel to check
1339 * @port: Port to check
1340 *
1341 * Returns true if @tunnel goes through @port (direction does not matter),
1342 * false otherwise.
1343 */
1344bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
1345 const struct tb_port *port)
1346{
1347 int i;
1348
1349 for (i = 0; i < tunnel->npaths; i++) {
1350 if (!tunnel->paths[i])
1351 continue;
1352
1353 if (tb_path_port_on_path(tunnel->paths[i], port))
1354 return true;
1355 }
1356
1357 return false;
1358}
1359
1360static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
1361{
1362 int i;
1363
1364 for (i = 0; i < tunnel->npaths; i++) {
1365 if (!tunnel->paths[i])
1366 return false;
1367 if (!tunnel->paths[i]->activated)
1368 return false;
1369 }
1370
1371 return true;
1372}
1373
1374/**
1375 * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
1376 * @tunnel: Tunnel to check
1377 * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port.
1378 * Can be %NULL.
1379 * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port.
1380 * Can be %NULL.
1381 *
1382 * Stores the amount of isochronous bandwidth @tunnel consumes in
1383 * @consumed_up and @consumed_down. In case of success returns %0,
1384 * negative errno otherwise.
1385 */
1386int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
1387 int *consumed_down)
1388{
1389 int up_bw = 0, down_bw = 0;
1390
1391 if (!tb_tunnel_is_active(tunnel))
1392 goto out;
1393
1394 if (tunnel->consumed_bandwidth) {
1395 int ret;
1396
1397 ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw);
1398 if (ret)
1399 return ret;
1400
1401 tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw,
1402 down_bw);
1403 }
1404
1405out:
1406 if (consumed_up)
1407 *consumed_up = up_bw;
1408 if (consumed_down)
1409 *consumed_down = down_bw;
1410
1411 return 0;
1412}
1413
1414/**
1415 * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth
1416 * @tunnel: Tunnel whose unused bandwidth to release
1417 *
1418 * If tunnel supports dynamic bandwidth management (USB3 tunnels at the
1419 * moment) this function makes it to release all the unused bandwidth.
1420 *
1421 * Returns %0 in case of success and negative errno otherwise.
1422 */
1423int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel)
1424{
1425 if (!tb_tunnel_is_active(tunnel))
1426 return 0;
1427
1428 if (tunnel->release_unused_bandwidth) {
1429 int ret;
1430
1431 ret = tunnel->release_unused_bandwidth(tunnel);
1432 if (ret)
1433 return ret;
1434 }
1435
1436 return 0;
1437}
1438
1439/**
1440 * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth
1441 * @tunnel: Tunnel reclaiming available bandwidth
1442 * @available_up: Available upstream bandwidth (in Mb/s)
1443 * @available_down: Available downstream bandwidth (in Mb/s)
1444 *
1445 * Reclaims bandwidth from @available_up and @available_down and updates
1446 * the variables accordingly (e.g decreases both according to what was
1447 * reclaimed by the tunnel). If nothing was reclaimed the values are
1448 * kept as is.
1449 */
1450void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
1451 int *available_up,
1452 int *available_down)
1453{
1454 if (!tb_tunnel_is_active(tunnel))
1455 return;
1456
1457 if (tunnel->reclaim_available_bandwidth)
1458 tunnel->reclaim_available_bandwidth(tunnel, available_up,
1459 available_down);
1460}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Thunderbolt driver - Tunneling support
4 *
5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
6 * Copyright (C) 2019, Intel Corporation
7 */
8
9#include <linux/slab.h>
10#include <linux/list.h>
11
12#include "tunnel.h"
13#include "tb.h"
14
15/* PCIe adapters use always HopID of 8 for both directions */
16#define TB_PCI_HOPID 8
17
18#define TB_PCI_PATH_DOWN 0
19#define TB_PCI_PATH_UP 1
20
21/* DP adapters use HopID 8 for AUX and 9 for Video */
22#define TB_DP_AUX_TX_HOPID 8
23#define TB_DP_AUX_RX_HOPID 8
24#define TB_DP_VIDEO_HOPID 9
25
26#define TB_DP_VIDEO_PATH_OUT 0
27#define TB_DP_AUX_PATH_OUT 1
28#define TB_DP_AUX_PATH_IN 2
29
30#define TB_DMA_PATH_OUT 0
31#define TB_DMA_PATH_IN 1
32
33static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA" };
34
35#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...) \
36 do { \
37 struct tb_tunnel *__tunnel = (tunnel); \
38 level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt, \
39 tb_route(__tunnel->src_port->sw), \
40 __tunnel->src_port->port, \
41 tb_route(__tunnel->dst_port->sw), \
42 __tunnel->dst_port->port, \
43 tb_tunnel_names[__tunnel->type], \
44 ## arg); \
45 } while (0)
46
47#define tb_tunnel_WARN(tunnel, fmt, arg...) \
48 __TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
49#define tb_tunnel_warn(tunnel, fmt, arg...) \
50 __TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
51#define tb_tunnel_info(tunnel, fmt, arg...) \
52 __TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
53#define tb_tunnel_dbg(tunnel, fmt, arg...) \
54 __TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
55
56static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
57 enum tb_tunnel_type type)
58{
59 struct tb_tunnel *tunnel;
60
61 tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
62 if (!tunnel)
63 return NULL;
64
65 tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
66 if (!tunnel->paths) {
67 tb_tunnel_free(tunnel);
68 return NULL;
69 }
70
71 INIT_LIST_HEAD(&tunnel->list);
72 tunnel->tb = tb;
73 tunnel->npaths = npaths;
74 tunnel->type = type;
75
76 return tunnel;
77}
78
79static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
80{
81 int res;
82
83 res = tb_pci_port_enable(tunnel->src_port, activate);
84 if (res)
85 return res;
86
87 if (tb_port_is_pcie_up(tunnel->dst_port))
88 return tb_pci_port_enable(tunnel->dst_port, activate);
89
90 return 0;
91}
92
93static void tb_pci_init_path(struct tb_path *path)
94{
95 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
96 path->egress_shared_buffer = TB_PATH_NONE;
97 path->ingress_fc_enable = TB_PATH_ALL;
98 path->ingress_shared_buffer = TB_PATH_NONE;
99 path->priority = 3;
100 path->weight = 1;
101 path->drop_packages = 0;
102 path->nfc_credits = 0;
103 path->hops[0].initial_credits = 7;
104 path->hops[1].initial_credits = 16;
105}
106
107/**
108 * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
109 * @tb: Pointer to the domain structure
110 * @down: PCIe downstream adapter
111 *
112 * If @down adapter is active, follows the tunnel to the PCIe upstream
113 * adapter and back. Returns the discovered tunnel or %NULL if there was
114 * no tunnel.
115 */
116struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
117{
118 struct tb_tunnel *tunnel;
119 struct tb_path *path;
120
121 if (!tb_pci_port_is_enabled(down))
122 return NULL;
123
124 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
125 if (!tunnel)
126 return NULL;
127
128 tunnel->activate = tb_pci_activate;
129 tunnel->src_port = down;
130
131 /*
132 * Discover both paths even if they are not complete. We will
133 * clean them up by calling tb_tunnel_deactivate() below in that
134 * case.
135 */
136 path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
137 &tunnel->dst_port, "PCIe Up");
138 if (!path) {
139 /* Just disable the downstream port */
140 tb_pci_port_enable(down, false);
141 goto err_free;
142 }
143 tunnel->paths[TB_PCI_PATH_UP] = path;
144 tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]);
145
146 path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
147 "PCIe Down");
148 if (!path)
149 goto err_deactivate;
150 tunnel->paths[TB_PCI_PATH_DOWN] = path;
151 tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]);
152
153 /* Validate that the tunnel is complete */
154 if (!tb_port_is_pcie_up(tunnel->dst_port)) {
155 tb_port_warn(tunnel->dst_port,
156 "path does not end on a PCIe adapter, cleaning up\n");
157 goto err_deactivate;
158 }
159
160 if (down != tunnel->src_port) {
161 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
162 goto err_deactivate;
163 }
164
165 if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
166 tb_tunnel_warn(tunnel,
167 "tunnel is not fully activated, cleaning up\n");
168 goto err_deactivate;
169 }
170
171 tb_tunnel_dbg(tunnel, "discovered\n");
172 return tunnel;
173
174err_deactivate:
175 tb_tunnel_deactivate(tunnel);
176err_free:
177 tb_tunnel_free(tunnel);
178
179 return NULL;
180}
181
182/**
183 * tb_tunnel_alloc_pci() - allocate a pci tunnel
184 * @tb: Pointer to the domain structure
185 * @up: PCIe upstream adapter port
186 * @down: PCIe downstream adapter port
187 *
188 * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
189 * TB_TYPE_PCIE_DOWN.
190 *
191 * Return: Returns a tb_tunnel on success or NULL on failure.
192 */
193struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
194 struct tb_port *down)
195{
196 struct tb_tunnel *tunnel;
197 struct tb_path *path;
198
199 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
200 if (!tunnel)
201 return NULL;
202
203 tunnel->activate = tb_pci_activate;
204 tunnel->src_port = down;
205 tunnel->dst_port = up;
206
207 path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
208 "PCIe Down");
209 if (!path) {
210 tb_tunnel_free(tunnel);
211 return NULL;
212 }
213 tb_pci_init_path(path);
214 tunnel->paths[TB_PCI_PATH_DOWN] = path;
215
216 path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
217 "PCIe Up");
218 if (!path) {
219 tb_tunnel_free(tunnel);
220 return NULL;
221 }
222 tb_pci_init_path(path);
223 tunnel->paths[TB_PCI_PATH_UP] = path;
224
225 return tunnel;
226}
227
228static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
229{
230 struct tb_port *out = tunnel->dst_port;
231 struct tb_port *in = tunnel->src_port;
232 u32 in_dp_cap, out_dp_cap;
233 int ret;
234
235 /*
236 * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
237 * newer generation hardware.
238 */
239 if (in->sw->generation < 2 || out->sw->generation < 2)
240 return 0;
241
242 /* Read both DP_LOCAL_CAP registers */
243 ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
244 in->cap_adap + TB_DP_LOCAL_CAP, 1);
245 if (ret)
246 return ret;
247
248 ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
249 out->cap_adap + TB_DP_LOCAL_CAP, 1);
250 if (ret)
251 return ret;
252
253 /* Write IN local caps to OUT remote caps */
254 ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
255 out->cap_adap + TB_DP_REMOTE_CAP, 1);
256 if (ret)
257 return ret;
258
259 return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
260 in->cap_adap + TB_DP_REMOTE_CAP, 1);
261}
262
263static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
264{
265 int ret;
266
267 if (active) {
268 struct tb_path **paths;
269 int last;
270
271 paths = tunnel->paths;
272 last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
273
274 tb_dp_port_set_hops(tunnel->src_port,
275 paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
276 paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
277 paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
278
279 tb_dp_port_set_hops(tunnel->dst_port,
280 paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
281 paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
282 paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
283 } else {
284 tb_dp_port_hpd_clear(tunnel->src_port);
285 tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
286 if (tb_port_is_dpout(tunnel->dst_port))
287 tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
288 }
289
290 ret = tb_dp_port_enable(tunnel->src_port, active);
291 if (ret)
292 return ret;
293
294 if (tb_port_is_dpout(tunnel->dst_port))
295 return tb_dp_port_enable(tunnel->dst_port, active);
296
297 return 0;
298}
299
300static void tb_dp_init_aux_path(struct tb_path *path)
301{
302 int i;
303
304 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
305 path->egress_shared_buffer = TB_PATH_NONE;
306 path->ingress_fc_enable = TB_PATH_ALL;
307 path->ingress_shared_buffer = TB_PATH_NONE;
308 path->priority = 2;
309 path->weight = 1;
310
311 for (i = 0; i < path->path_length; i++)
312 path->hops[i].initial_credits = 1;
313}
314
315static void tb_dp_init_video_path(struct tb_path *path, bool discover)
316{
317 u32 nfc_credits = path->hops[0].in_port->config.nfc_credits;
318
319 path->egress_fc_enable = TB_PATH_NONE;
320 path->egress_shared_buffer = TB_PATH_NONE;
321 path->ingress_fc_enable = TB_PATH_NONE;
322 path->ingress_shared_buffer = TB_PATH_NONE;
323 path->priority = 1;
324 path->weight = 1;
325
326 if (discover) {
327 path->nfc_credits = nfc_credits & TB_PORT_NFC_CREDITS_MASK;
328 } else {
329 u32 max_credits;
330
331 max_credits = (nfc_credits & TB_PORT_MAX_CREDITS_MASK) >>
332 TB_PORT_MAX_CREDITS_SHIFT;
333 /* Leave some credits for AUX path */
334 path->nfc_credits = min(max_credits - 2, 12U);
335 }
336}
337
338/**
339 * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
340 * @tb: Pointer to the domain structure
341 * @in: DP in adapter
342 *
343 * If @in adapter is active, follows the tunnel to the DP out adapter
344 * and back. Returns the discovered tunnel or %NULL if there was no
345 * tunnel.
346 *
347 * Return: DP tunnel or %NULL if no tunnel found.
348 */
349struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
350{
351 struct tb_tunnel *tunnel;
352 struct tb_port *port;
353 struct tb_path *path;
354
355 if (!tb_dp_port_is_enabled(in))
356 return NULL;
357
358 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
359 if (!tunnel)
360 return NULL;
361
362 tunnel->init = tb_dp_xchg_caps;
363 tunnel->activate = tb_dp_activate;
364 tunnel->src_port = in;
365
366 path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
367 &tunnel->dst_port, "Video");
368 if (!path) {
369 /* Just disable the DP IN port */
370 tb_dp_port_enable(in, false);
371 goto err_free;
372 }
373 tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
374 tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], true);
375
376 path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
377 if (!path)
378 goto err_deactivate;
379 tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
380 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
381
382 path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
383 &port, "AUX RX");
384 if (!path)
385 goto err_deactivate;
386 tunnel->paths[TB_DP_AUX_PATH_IN] = path;
387 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);
388
389 /* Validate that the tunnel is complete */
390 if (!tb_port_is_dpout(tunnel->dst_port)) {
391 tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
392 goto err_deactivate;
393 }
394
395 if (!tb_dp_port_is_enabled(tunnel->dst_port))
396 goto err_deactivate;
397
398 if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
399 goto err_deactivate;
400
401 if (port != tunnel->src_port) {
402 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
403 goto err_deactivate;
404 }
405
406 tb_tunnel_dbg(tunnel, "discovered\n");
407 return tunnel;
408
409err_deactivate:
410 tb_tunnel_deactivate(tunnel);
411err_free:
412 tb_tunnel_free(tunnel);
413
414 return NULL;
415}
416
417/**
418 * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
419 * @tb: Pointer to the domain structure
420 * @in: DP in adapter port
421 * @out: DP out adapter port
422 *
423 * Allocates a tunnel between @in and @out that is capable of tunneling
424 * Display Port traffic.
425 *
426 * Return: Returns a tb_tunnel on success or NULL on failure.
427 */
428struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
429 struct tb_port *out)
430{
431 struct tb_tunnel *tunnel;
432 struct tb_path **paths;
433 struct tb_path *path;
434
435 if (WARN_ON(!in->cap_adap || !out->cap_adap))
436 return NULL;
437
438 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
439 if (!tunnel)
440 return NULL;
441
442 tunnel->init = tb_dp_xchg_caps;
443 tunnel->activate = tb_dp_activate;
444 tunnel->src_port = in;
445 tunnel->dst_port = out;
446
447 paths = tunnel->paths;
448
449 path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
450 1, "Video");
451 if (!path)
452 goto err_free;
453 tb_dp_init_video_path(path, false);
454 paths[TB_DP_VIDEO_PATH_OUT] = path;
455
456 path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
457 TB_DP_AUX_TX_HOPID, 1, "AUX TX");
458 if (!path)
459 goto err_free;
460 tb_dp_init_aux_path(path);
461 paths[TB_DP_AUX_PATH_OUT] = path;
462
463 path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
464 TB_DP_AUX_RX_HOPID, 1, "AUX RX");
465 if (!path)
466 goto err_free;
467 tb_dp_init_aux_path(path);
468 paths[TB_DP_AUX_PATH_IN] = path;
469
470 return tunnel;
471
472err_free:
473 tb_tunnel_free(tunnel);
474 return NULL;
475}
476
477static u32 tb_dma_credits(struct tb_port *nhi)
478{
479 u32 max_credits;
480
481 max_credits = (nhi->config.nfc_credits & TB_PORT_MAX_CREDITS_MASK) >>
482 TB_PORT_MAX_CREDITS_SHIFT;
483 return min(max_credits, 13U);
484}
485
486static int tb_dma_activate(struct tb_tunnel *tunnel, bool active)
487{
488 struct tb_port *nhi = tunnel->src_port;
489 u32 credits;
490
491 credits = active ? tb_dma_credits(nhi) : 0;
492 return tb_port_set_initial_credits(nhi, credits);
493}
494
495static void tb_dma_init_path(struct tb_path *path, unsigned int isb,
496 unsigned int efc, u32 credits)
497{
498 int i;
499
500 path->egress_fc_enable = efc;
501 path->ingress_fc_enable = TB_PATH_ALL;
502 path->egress_shared_buffer = TB_PATH_NONE;
503 path->ingress_shared_buffer = isb;
504 path->priority = 5;
505 path->weight = 1;
506 path->clear_fc = true;
507
508 for (i = 0; i < path->path_length; i++)
509 path->hops[i].initial_credits = credits;
510}
511
512/**
513 * tb_tunnel_alloc_dma() - allocate a DMA tunnel
514 * @tb: Pointer to the domain structure
515 * @nhi: Host controller port
516 * @dst: Destination null port which the other domain is connected to
517 * @transmit_ring: NHI ring number used to send packets towards the
518 * other domain
519 * @transmit_path: HopID used for transmitting packets
520 * @receive_ring: NHI ring number used to receive packets from the
521 * other domain
522 * @reveive_path: HopID used for receiving packets
523 *
524 * Return: Returns a tb_tunnel on success or NULL on failure.
525 */
526struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
527 struct tb_port *dst, int transmit_ring,
528 int transmit_path, int receive_ring,
529 int receive_path)
530{
531 struct tb_tunnel *tunnel;
532 struct tb_path *path;
533 u32 credits;
534
535 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);
536 if (!tunnel)
537 return NULL;
538
539 tunnel->activate = tb_dma_activate;
540 tunnel->src_port = nhi;
541 tunnel->dst_port = dst;
542
543 credits = tb_dma_credits(nhi);
544
545 path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX");
546 if (!path) {
547 tb_tunnel_free(tunnel);
548 return NULL;
549 }
550 tb_dma_init_path(path, TB_PATH_NONE, TB_PATH_SOURCE | TB_PATH_INTERNAL,
551 credits);
552 tunnel->paths[TB_DMA_PATH_IN] = path;
553
554 path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX");
555 if (!path) {
556 tb_tunnel_free(tunnel);
557 return NULL;
558 }
559 tb_dma_init_path(path, TB_PATH_SOURCE, TB_PATH_ALL, credits);
560 tunnel->paths[TB_DMA_PATH_OUT] = path;
561
562 return tunnel;
563}
564
565/**
566 * tb_tunnel_free() - free a tunnel
567 * @tunnel: Tunnel to be freed
568 *
569 * Frees a tunnel. The tunnel does not need to be deactivated.
570 */
571void tb_tunnel_free(struct tb_tunnel *tunnel)
572{
573 int i;
574
575 if (!tunnel)
576 return;
577
578 for (i = 0; i < tunnel->npaths; i++) {
579 if (tunnel->paths[i])
580 tb_path_free(tunnel->paths[i]);
581 }
582
583 kfree(tunnel->paths);
584 kfree(tunnel);
585}
586
587/**
588 * tb_tunnel_is_invalid - check whether an activated path is still valid
589 * @tunnel: Tunnel to check
590 */
591bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
592{
593 int i;
594
595 for (i = 0; i < tunnel->npaths; i++) {
596 WARN_ON(!tunnel->paths[i]->activated);
597 if (tb_path_is_invalid(tunnel->paths[i]))
598 return true;
599 }
600
601 return false;
602}
603
604/**
605 * tb_tunnel_restart() - activate a tunnel after a hardware reset
606 * @tunnel: Tunnel to restart
607 *
608 * Return: 0 on success and negative errno in case if failure
609 */
610int tb_tunnel_restart(struct tb_tunnel *tunnel)
611{
612 int res, i;
613
614 tb_tunnel_dbg(tunnel, "activating\n");
615
616 /*
617 * Make sure all paths are properly disabled before enabling
618 * them again.
619 */
620 for (i = 0; i < tunnel->npaths; i++) {
621 if (tunnel->paths[i]->activated) {
622 tb_path_deactivate(tunnel->paths[i]);
623 tunnel->paths[i]->activated = false;
624 }
625 }
626
627 if (tunnel->init) {
628 res = tunnel->init(tunnel);
629 if (res)
630 return res;
631 }
632
633 for (i = 0; i < tunnel->npaths; i++) {
634 res = tb_path_activate(tunnel->paths[i]);
635 if (res)
636 goto err;
637 }
638
639 if (tunnel->activate) {
640 res = tunnel->activate(tunnel, true);
641 if (res)
642 goto err;
643 }
644
645 return 0;
646
647err:
648 tb_tunnel_warn(tunnel, "activation failed\n");
649 tb_tunnel_deactivate(tunnel);
650 return res;
651}
652
653/**
654 * tb_tunnel_activate() - activate a tunnel
655 * @tunnel: Tunnel to activate
656 *
657 * Return: Returns 0 on success or an error code on failure.
658 */
659int tb_tunnel_activate(struct tb_tunnel *tunnel)
660{
661 int i;
662
663 for (i = 0; i < tunnel->npaths; i++) {
664 if (tunnel->paths[i]->activated) {
665 tb_tunnel_WARN(tunnel,
666 "trying to activate an already activated tunnel\n");
667 return -EINVAL;
668 }
669 }
670
671 return tb_tunnel_restart(tunnel);
672}
673
674/**
675 * tb_tunnel_deactivate() - deactivate a tunnel
676 * @tunnel: Tunnel to deactivate
677 */
678void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
679{
680 int i;
681
682 tb_tunnel_dbg(tunnel, "deactivating\n");
683
684 if (tunnel->activate)
685 tunnel->activate(tunnel, false);
686
687 for (i = 0; i < tunnel->npaths; i++) {
688 if (tunnel->paths[i] && tunnel->paths[i]->activated)
689 tb_path_deactivate(tunnel->paths[i]);
690 }
691}