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Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...
[drm/drm-misc.git] / drivers / thunderbolt / tunnel.c
blob41cf6378ad2516ca4eaffcf28681db35611032d5
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 #include <linux/ktime.h>
13 #include <linux/string_helpers.h>
14
15 #include "tunnel.h"
16 #include "tb.h"
17
18 /* PCIe adapters use always HopID of 8 for both directions */
19 #define TB_PCI_HOPID 8
20
21 #define TB_PCI_PATH_DOWN 0
22 #define TB_PCI_PATH_UP 1
23
24 #define TB_PCI_PRIORITY 3
25 #define TB_PCI_WEIGHT 1
26
27 /* USB3 adapters use always HopID of 8 for both directions */
28 #define TB_USB3_HOPID 8
29
30 #define TB_USB3_PATH_DOWN 0
31 #define TB_USB3_PATH_UP 1
32
33 #define TB_USB3_PRIORITY 3
34 #define TB_USB3_WEIGHT 2
35
36 /* DP adapters use HopID 8 for AUX and 9 for Video */
37 #define TB_DP_AUX_TX_HOPID 8
38 #define TB_DP_AUX_RX_HOPID 8
39 #define TB_DP_VIDEO_HOPID 9
40
41 #define TB_DP_VIDEO_PATH_OUT 0
42 #define TB_DP_AUX_PATH_OUT 1
43 #define TB_DP_AUX_PATH_IN 2
44
45 #define TB_DP_VIDEO_PRIORITY 1
46 #define TB_DP_VIDEO_WEIGHT 1
47
48 #define TB_DP_AUX_PRIORITY 2
49 #define TB_DP_AUX_WEIGHT 1
50
51 /* Minimum number of credits needed for PCIe path */
52 #define TB_MIN_PCIE_CREDITS 6U
53 /*
54 * Number of credits we try to allocate for each DMA path if not limited
55 * by the host router baMaxHI.
56 */
57 #define TB_DMA_CREDITS 14
58 /* Minimum number of credits for DMA path */
59 #define TB_MIN_DMA_CREDITS 1
60
61 #define TB_DMA_PRIORITY 5
62 #define TB_DMA_WEIGHT 1
63
64 /*
65 * Reserve additional bandwidth for USB 3.x and PCIe bulk traffic
66 * according to USB4 v2 Connection Manager guide. This ends up reserving
67 * 1500 Mb/s for PCIe and 3000 Mb/s for USB 3.x taking weights into
68 * account.
69 */
70 #define USB4_V2_PCI_MIN_BANDWIDTH (1500 * TB_PCI_WEIGHT)
71 #define USB4_V2_USB3_MIN_BANDWIDTH (1500 * TB_USB3_WEIGHT)
72
73 static unsigned int dma_credits = TB_DMA_CREDITS;
74 module_param(dma_credits, uint, 0444);
75 MODULE_PARM_DESC(dma_credits, "specify custom credits for DMA tunnels (default: "
76 __MODULE_STRING(TB_DMA_CREDITS) ")");
77
78 static bool bw_alloc_mode = true;
79 module_param(bw_alloc_mode, bool, 0444);
80 MODULE_PARM_DESC(bw_alloc_mode,
81 "enable bandwidth allocation mode if supported (default: true)");
82
83 static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };
84
85 static inline unsigned int tb_usable_credits(const struct tb_port *port)
86 {
87 return port->total_credits - port->ctl_credits;
88 }
89
90 /**
91 * tb_available_credits() - Available credits for PCIe and DMA
92 * @port: Lane adapter to check
93 * @max_dp_streams: If non-%NULL stores maximum number of simultaneous DP
94 * streams possible through this lane adapter
95 */
96 static unsigned int tb_available_credits(const struct tb_port *port,
97 size_t *max_dp_streams)
98 {
99 const struct tb_switch *sw = port->sw;
100 int credits, usb3, pcie, spare;
101 size_t ndp;
102
103 usb3 = tb_acpi_may_tunnel_usb3() ? sw->max_usb3_credits : 0;
104 pcie = tb_acpi_may_tunnel_pcie() ? sw->max_pcie_credits : 0;
105
106 if (tb_acpi_is_xdomain_allowed()) {
107 spare = min_not_zero(sw->max_dma_credits, dma_credits);
108 /* Add some credits for potential second DMA tunnel */
109 spare += TB_MIN_DMA_CREDITS;
110 } else {
111 spare = 0;
112 }
113
114 credits = tb_usable_credits(port);
115 if (tb_acpi_may_tunnel_dp()) {
116 /*
117 * Maximum number of DP streams possible through the
118 * lane adapter.
119 */
120 if (sw->min_dp_aux_credits + sw->min_dp_main_credits)
121 ndp = (credits - (usb3 + pcie + spare)) /
122 (sw->min_dp_aux_credits + sw->min_dp_main_credits);
123 else
124 ndp = 0;
125 } else {
126 ndp = 0;
127 }
128 credits -= ndp * (sw->min_dp_aux_credits + sw->min_dp_main_credits);
129 credits -= usb3;
130
131 if (max_dp_streams)
132 *max_dp_streams = ndp;
133
134 return credits > 0 ? credits : 0;
135 }
136
137 static void tb_init_pm_support(struct tb_path_hop *hop)
138 {
139 struct tb_port *out_port = hop->out_port;
140 struct tb_port *in_port = hop->in_port;
141
142 if (tb_port_is_null(in_port) && tb_port_is_null(out_port) &&
143 usb4_switch_version(in_port->sw) >= 2)
144 hop->pm_support = true;
145 }
146
147 static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
148 enum tb_tunnel_type type)
149 {
150 struct tb_tunnel *tunnel;
151
152 tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
153 if (!tunnel)
154 return NULL;
155
156 tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
157 if (!tunnel->paths) {
158 tb_tunnel_free(tunnel);
159 return NULL;
160 }
161
162 INIT_LIST_HEAD(&tunnel->list);
163 tunnel->tb = tb;
164 tunnel->npaths = npaths;
165 tunnel->type = type;
166
167 return tunnel;
168 }
169
170 static int tb_pci_set_ext_encapsulation(struct tb_tunnel *tunnel, bool enable)
171 {
172 struct tb_port *port = tb_upstream_port(tunnel->dst_port->sw);
173 int ret;
174
175 /* Only supported of both routers are at least USB4 v2 */
176 if ((usb4_switch_version(tunnel->src_port->sw) < 2) ||
177 (usb4_switch_version(tunnel->dst_port->sw) < 2))
178 return 0;
179
180 if (enable && tb_port_get_link_generation(port) < 4)
181 return 0;
182
183 ret = usb4_pci_port_set_ext_encapsulation(tunnel->src_port, enable);
184 if (ret)
185 return ret;
186
187 /*
188 * Downstream router could be unplugged so disable of encapsulation
189 * in upstream router is still possible.
190 */
191 ret = usb4_pci_port_set_ext_encapsulation(tunnel->dst_port, enable);
192 if (ret) {
193 if (enable)
194 return ret;
195 if (ret != -ENODEV)
196 return ret;
197 }
198
199 tb_tunnel_dbg(tunnel, "extended encapsulation %s\n",
200 str_enabled_disabled(enable));
201 return 0;
202 }
203
204 static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
205 {
206 int res;
207
208 if (activate) {
209 res = tb_pci_set_ext_encapsulation(tunnel, activate);
210 if (res)
211 return res;
212 }
213
214 if (activate)
215 res = tb_pci_port_enable(tunnel->dst_port, activate);
216 else
217 res = tb_pci_port_enable(tunnel->src_port, activate);
218 if (res)
219 return res;
220
221
222 if (activate) {
223 res = tb_pci_port_enable(tunnel->src_port, activate);
224 if (res)
225 return res;
226 } else {
227 /* Downstream router could be unplugged */
228 tb_pci_port_enable(tunnel->dst_port, activate);
229 }
230
231 return activate ? 0 : tb_pci_set_ext_encapsulation(tunnel, activate);
232 }
233
234 static int tb_pci_init_credits(struct tb_path_hop *hop)
235 {
236 struct tb_port *port = hop->in_port;
237 struct tb_switch *sw = port->sw;
238 unsigned int credits;
239
240 if (tb_port_use_credit_allocation(port)) {
241 unsigned int available;
242
243 available = tb_available_credits(port, NULL);
244 credits = min(sw->max_pcie_credits, available);
245
246 if (credits < TB_MIN_PCIE_CREDITS)
247 return -ENOSPC;
248
249 credits = max(TB_MIN_PCIE_CREDITS, credits);
250 } else {
251 if (tb_port_is_null(port))
252 credits = port->bonded ? 32 : 16;
253 else
254 credits = 7;
255 }
256
257 hop->initial_credits = credits;
258 return 0;
259 }
260
261 static int tb_pci_init_path(struct tb_path *path)
262 {
263 struct tb_path_hop *hop;
264
265 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
266 path->egress_shared_buffer = TB_PATH_NONE;
267 path->ingress_fc_enable = TB_PATH_ALL;
268 path->ingress_shared_buffer = TB_PATH_NONE;
269 path->priority = TB_PCI_PRIORITY;
270 path->weight = TB_PCI_WEIGHT;
271 path->drop_packages = 0;
272
273 tb_path_for_each_hop(path, hop) {
274 int ret;
275
276 ret = tb_pci_init_credits(hop);
277 if (ret)
278 return ret;
279 }
280
281 return 0;
282 }
283
284 /**
285 * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
286 * @tb: Pointer to the domain structure
287 * @down: PCIe downstream adapter
288 * @alloc_hopid: Allocate HopIDs from visited ports
289 *
290 * If @down adapter is active, follows the tunnel to the PCIe upstream
291 * adapter and back. Returns the discovered tunnel or %NULL if there was
292 * no tunnel.
293 */
294 struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down,
295 bool alloc_hopid)
296 {
297 struct tb_tunnel *tunnel;
298 struct tb_path *path;
299
300 if (!tb_pci_port_is_enabled(down))
301 return NULL;
302
303 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
304 if (!tunnel)
305 return NULL;
306
307 tunnel->activate = tb_pci_activate;
308 tunnel->src_port = down;
309
310 /*
311 * Discover both paths even if they are not complete. We will
312 * clean them up by calling tb_tunnel_deactivate() below in that
313 * case.
314 */
315 path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
316 &tunnel->dst_port, "PCIe Up", alloc_hopid);
317 if (!path) {
318 /* Just disable the downstream port */
319 tb_pci_port_enable(down, false);
320 goto err_free;
321 }
322 tunnel->paths[TB_PCI_PATH_UP] = path;
323 if (tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]))
324 goto err_free;
325
326 path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
327 "PCIe Down", alloc_hopid);
328 if (!path)
329 goto err_deactivate;
330 tunnel->paths[TB_PCI_PATH_DOWN] = path;
331 if (tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]))
332 goto err_deactivate;
333
334 /* Validate that the tunnel is complete */
335 if (!tb_port_is_pcie_up(tunnel->dst_port)) {
336 tb_port_warn(tunnel->dst_port,
337 "path does not end on a PCIe adapter, cleaning up\n");
338 goto err_deactivate;
339 }
340
341 if (down != tunnel->src_port) {
342 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
343 goto err_deactivate;
344 }
345
346 if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
347 tb_tunnel_warn(tunnel,
348 "tunnel is not fully activated, cleaning up\n");
349 goto err_deactivate;
350 }
351
352 tb_tunnel_dbg(tunnel, "discovered\n");
353 return tunnel;
354
355 err_deactivate:
356 tb_tunnel_deactivate(tunnel);
357 err_free:
358 tb_tunnel_free(tunnel);
359
360 return NULL;
361 }
362
363 /**
364 * tb_tunnel_alloc_pci() - allocate a pci tunnel
365 * @tb: Pointer to the domain structure
366 * @up: PCIe upstream adapter port
367 * @down: PCIe downstream adapter port
368 *
369 * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
370 * TB_TYPE_PCIE_DOWN.
371 *
372 * Return: Returns a tb_tunnel on success or NULL on failure.
373 */
374 struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
375 struct tb_port *down)
376 {
377 struct tb_tunnel *tunnel;
378 struct tb_path *path;
379
380 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
381 if (!tunnel)
382 return NULL;
383
384 tunnel->activate = tb_pci_activate;
385 tunnel->src_port = down;
386 tunnel->dst_port = up;
387
388 path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
389 "PCIe Down");
390 if (!path)
391 goto err_free;
392 tunnel->paths[TB_PCI_PATH_DOWN] = path;
393 if (tb_pci_init_path(path))
394 goto err_free;
395
396 path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
397 "PCIe Up");
398 if (!path)
399 goto err_free;
400 tunnel->paths[TB_PCI_PATH_UP] = path;
401 if (tb_pci_init_path(path))
402 goto err_free;
403
404 return tunnel;
405
406 err_free:
407 tb_tunnel_free(tunnel);
408 return NULL;
409 }
410
411 /**
412 * tb_tunnel_reserved_pci() - Amount of bandwidth to reserve for PCIe
413 * @port: Lane 0 adapter
414 * @reserved_up: Upstream bandwidth in Mb/s to reserve
415 * @reserved_down: Downstream bandwidth in Mb/s to reserve
416 *
417 * Can be called to any connected lane 0 adapter to find out how much
418 * bandwidth needs to be left in reserve for possible PCIe bulk traffic.
419 * Returns true if there is something to be reserved and writes the
420 * amount to @reserved_down/@reserved_up. Otherwise returns false and
421 * does not touch the parameters.
422 */
423 bool tb_tunnel_reserved_pci(struct tb_port *port, int *reserved_up,
424 int *reserved_down)
425 {
426 if (WARN_ON_ONCE(!port->remote))
427 return false;
428
429 if (!tb_acpi_may_tunnel_pcie())
430 return false;
431
432 if (tb_port_get_link_generation(port) < 4)
433 return false;
434
435 /* Must have PCIe adapters */
436 if (tb_is_upstream_port(port)) {
437 if (!tb_switch_find_port(port->sw, TB_TYPE_PCIE_UP))
438 return false;
439 if (!tb_switch_find_port(port->remote->sw, TB_TYPE_PCIE_DOWN))
440 return false;
441 } else {
442 if (!tb_switch_find_port(port->sw, TB_TYPE_PCIE_DOWN))
443 return false;
444 if (!tb_switch_find_port(port->remote->sw, TB_TYPE_PCIE_UP))
445 return false;
446 }
447
448 *reserved_up = USB4_V2_PCI_MIN_BANDWIDTH;
449 *reserved_down = USB4_V2_PCI_MIN_BANDWIDTH;
450
451 tb_port_dbg(port, "reserving %u/%u Mb/s for PCIe\n", *reserved_up,
452 *reserved_down);
453 return true;
454 }
455
456 static bool tb_dp_is_usb4(const struct tb_switch *sw)
457 {
458 /* Titan Ridge DP adapters need the same treatment as USB4 */
459 return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
460 }
461
462 static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out,
463 int timeout_msec)
464 {
465 ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec);
466 u32 val;
467 int ret;
468
469 /* Both ends need to support this */
470 if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
471 return 0;
472
473 ret = tb_port_read(out, &val, TB_CFG_PORT,
474 out->cap_adap + DP_STATUS_CTRL, 1);
475 if (ret)
476 return ret;
477
478 val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;
479
480 ret = tb_port_write(out, &val, TB_CFG_PORT,
481 out->cap_adap + DP_STATUS_CTRL, 1);
482 if (ret)
483 return ret;
484
485 do {
486 ret = tb_port_read(out, &val, TB_CFG_PORT,
487 out->cap_adap + DP_STATUS_CTRL, 1);
488 if (ret)
489 return ret;
490 if (!(val & DP_STATUS_CTRL_CMHS))
491 return 0;
492 usleep_range(100, 150);
493 } while (ktime_before(ktime_get(), timeout));
494
495 return -ETIMEDOUT;
496 }
497
498 /*
499 * Returns maximum possible rate from capability supporting only DP 2.0
500 * and below. Used when DP BW allocation mode is not enabled.
501 */
502 static inline u32 tb_dp_cap_get_rate(u32 val)
503 {
504 u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;
505
506 switch (rate) {
507 case DP_COMMON_CAP_RATE_RBR:
508 return 1620;
509 case DP_COMMON_CAP_RATE_HBR:
510 return 2700;
511 case DP_COMMON_CAP_RATE_HBR2:
512 return 5400;
513 case DP_COMMON_CAP_RATE_HBR3:
514 return 8100;
515 default:
516 return 0;
517 }
518 }
519
520 /*
521 * Returns maximum possible rate from capability supporting DP 2.1
522 * UHBR20, 13.5 and 10 rates as well. Use only when DP BW allocation
523 * mode is enabled.
524 */
525 static inline u32 tb_dp_cap_get_rate_ext(u32 val)
526 {
527 if (val & DP_COMMON_CAP_UHBR20)
528 return 20000;
529 else if (val & DP_COMMON_CAP_UHBR13_5)
530 return 13500;
531 else if (val & DP_COMMON_CAP_UHBR10)
532 return 10000;
533
534 return tb_dp_cap_get_rate(val);
535 }
536
537 static inline bool tb_dp_is_uhbr_rate(unsigned int rate)
538 {
539 return rate >= 10000;
540 }
541
542 static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
543 {
544 val &= ~DP_COMMON_CAP_RATE_MASK;
545 switch (rate) {
546 default:
547 WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
548 fallthrough;
549 case 1620:
550 val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
551 break;
552 case 2700:
553 val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
554 break;
555 case 5400:
556 val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
557 break;
558 case 8100:
559 val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
560 break;
561 }
562 return val;
563 }
564
565 static inline u32 tb_dp_cap_get_lanes(u32 val)
566 {
567 u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;
568
569 switch (lanes) {
570 case DP_COMMON_CAP_1_LANE:
571 return 1;
572 case DP_COMMON_CAP_2_LANES:
573 return 2;
574 case DP_COMMON_CAP_4_LANES:
575 return 4;
576 default:
577 return 0;
578 }
579 }
580
581 static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
582 {
583 val &= ~DP_COMMON_CAP_LANES_MASK;
584 switch (lanes) {
585 default:
586 WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
587 lanes);
588 fallthrough;
589 case 1:
590 val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
591 break;
592 case 2:
593 val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
594 break;
595 case 4:
596 val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
597 break;
598 }
599 return val;
600 }
601
602 static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
603 {
604 /* Tunneling removes the DP 8b/10b 128/132b encoding */
605 if (tb_dp_is_uhbr_rate(rate))
606 return rate * lanes * 128 / 132;
607 return rate * lanes * 8 / 10;
608 }
609
610 static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes,
611 u32 out_rate, u32 out_lanes, u32 *new_rate,
612 u32 *new_lanes)
613 {
614 static const u32 dp_bw[][2] = {
615 /* Mb/s, lanes */
616 { 8100, 4 }, /* 25920 Mb/s */
617 { 5400, 4 }, /* 17280 Mb/s */
618 { 8100, 2 }, /* 12960 Mb/s */
619 { 2700, 4 }, /* 8640 Mb/s */
620 { 5400, 2 }, /* 8640 Mb/s */
621 { 8100, 1 }, /* 6480 Mb/s */
622 { 1620, 4 }, /* 5184 Mb/s */
623 { 5400, 1 }, /* 4320 Mb/s */
624 { 2700, 2 }, /* 4320 Mb/s */
625 { 1620, 2 }, /* 2592 Mb/s */
626 { 2700, 1 }, /* 2160 Mb/s */
627 { 1620, 1 }, /* 1296 Mb/s */
628 };
629 unsigned int i;
630
631 /*
632 * Find a combination that can fit into max_bw and does not
633 * exceed the maximum rate and lanes supported by the DP OUT and
634 * DP IN adapters.
635 */
636 for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
637 if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
638 continue;
639
640 if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
641 continue;
642
643 if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
644 *new_rate = dp_bw[i][0];
645 *new_lanes = dp_bw[i][1];
646 return 0;
647 }
648 }
649
650 return -ENOSR;
651 }
652
653 static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
654 {
655 u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
656 struct tb_port *out = tunnel->dst_port;
657 struct tb_port *in = tunnel->src_port;
658 int ret, max_bw;
659
660 /*
661 * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
662 * newer generation hardware.
663 */
664 if (in->sw->generation < 2 || out->sw->generation < 2)
665 return 0;
666
667 /*
668 * Perform connection manager handshake between IN and OUT ports
669 * before capabilities exchange can take place.
670 */
671 ret = tb_dp_cm_handshake(in, out, 3000);
672 if (ret)
673 return ret;
674
675 /* Read both DP_LOCAL_CAP registers */
676 ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
677 in->cap_adap + DP_LOCAL_CAP, 1);
678 if (ret)
679 return ret;
680
681 ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
682 out->cap_adap + DP_LOCAL_CAP, 1);
683 if (ret)
684 return ret;
685
686 /* Write IN local caps to OUT remote caps */
687 ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
688 out->cap_adap + DP_REMOTE_CAP, 1);
689 if (ret)
690 return ret;
691
692 in_rate = tb_dp_cap_get_rate(in_dp_cap);
693 in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
694 tb_tunnel_dbg(tunnel,
695 "DP IN maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
696 in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));
697
698 /*
699 * If the tunnel bandwidth is limited (max_bw is set) then see
700 * if we need to reduce bandwidth to fit there.
701 */
702 out_rate = tb_dp_cap_get_rate(out_dp_cap);
703 out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
704 bw = tb_dp_bandwidth(out_rate, out_lanes);
705 tb_tunnel_dbg(tunnel,
706 "DP OUT maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
707 out_rate, out_lanes, bw);
708
709 if (tb_tunnel_direction_downstream(tunnel))
710 max_bw = tunnel->max_down;
711 else
712 max_bw = tunnel->max_up;
713
714 if (max_bw && bw > max_bw) {
715 u32 new_rate, new_lanes, new_bw;
716
717 ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes,
718 out_rate, out_lanes, &new_rate,
719 &new_lanes);
720 if (ret) {
721 tb_tunnel_info(tunnel, "not enough bandwidth\n");
722 return ret;
723 }
724
725 new_bw = tb_dp_bandwidth(new_rate, new_lanes);
726 tb_tunnel_dbg(tunnel,
727 "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
728 new_rate, new_lanes, new_bw);
729
730 /*
731 * Set new rate and number of lanes before writing it to
732 * the IN port remote caps.
733 */
734 out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
735 out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
736 }
737
738 /*
739 * Titan Ridge does not disable AUX timers when it gets
740 * SET_CONFIG with SET_LTTPR_MODE set. This causes problems with
741 * DP tunneling.
742 */
743 if (tb_route(out->sw) && tb_switch_is_titan_ridge(out->sw)) {
744 out_dp_cap |= DP_COMMON_CAP_LTTPR_NS;
745 tb_tunnel_dbg(tunnel, "disabling LTTPR\n");
746 }
747
748 return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
749 in->cap_adap + DP_REMOTE_CAP, 1);
750 }
751
752 static int tb_dp_bandwidth_alloc_mode_enable(struct tb_tunnel *tunnel)
753 {
754 int ret, estimated_bw, granularity, tmp;
755 struct tb_port *out = tunnel->dst_port;
756 struct tb_port *in = tunnel->src_port;
757 u32 out_dp_cap, out_rate, out_lanes;
758 u32 in_dp_cap, in_rate, in_lanes;
759 u32 rate, lanes;
760
761 if (!bw_alloc_mode)
762 return 0;
763
764 ret = usb4_dp_port_set_cm_bandwidth_mode_supported(in, true);
765 if (ret)
766 return ret;
767
768 ret = usb4_dp_port_set_group_id(in, in->group->index);
769 if (ret)
770 return ret;
771
772 /*
773 * Get the non-reduced rate and lanes based on the lowest
774 * capability of both adapters.
775 */
776 ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
777 in->cap_adap + DP_LOCAL_CAP, 1);
778 if (ret)
779 return ret;
780
781 ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
782 out->cap_adap + DP_LOCAL_CAP, 1);
783 if (ret)
784 return ret;
785
786 in_rate = tb_dp_cap_get_rate(in_dp_cap);
787 in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
788 out_rate = tb_dp_cap_get_rate(out_dp_cap);
789 out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
790
791 rate = min(in_rate, out_rate);
792 lanes = min(in_lanes, out_lanes);
793 tmp = tb_dp_bandwidth(rate, lanes);
794
795 tb_tunnel_dbg(tunnel, "non-reduced bandwidth %u Mb/s x%u = %u Mb/s\n",
796 rate, lanes, tmp);
797
798 ret = usb4_dp_port_set_nrd(in, rate, lanes);
799 if (ret)
800 return ret;
801
802 /*
803 * Pick up granularity that supports maximum possible bandwidth.
804 * For that we use the UHBR rates too.
805 */
806 in_rate = tb_dp_cap_get_rate_ext(in_dp_cap);
807 out_rate = tb_dp_cap_get_rate_ext(out_dp_cap);
808 rate = min(in_rate, out_rate);
809 tmp = tb_dp_bandwidth(rate, lanes);
810
811 tb_tunnel_dbg(tunnel,
812 "maximum bandwidth through allocation mode %u Mb/s x%u = %u Mb/s\n",
813 rate, lanes, tmp);
814
815 for (granularity = 250; tmp / granularity > 255 && granularity <= 1000;
816 granularity *= 2)
817 ;
818
819 tb_tunnel_dbg(tunnel, "granularity %d Mb/s\n", granularity);
820
821 /*
822 * Returns -EINVAL if granularity above is outside of the
823 * accepted ranges.
824 */
825 ret = usb4_dp_port_set_granularity(in, granularity);
826 if (ret)
827 return ret;
828
829 /*
830 * Bandwidth estimation is pretty much what we have in
831 * max_up/down fields. For discovery we just read what the
832 * estimation was set to.
833 */
834 if (tb_tunnel_direction_downstream(tunnel))
835 estimated_bw = tunnel->max_down;
836 else
837 estimated_bw = tunnel->max_up;
838
839 tb_tunnel_dbg(tunnel, "estimated bandwidth %d Mb/s\n", estimated_bw);
840
841 ret = usb4_dp_port_set_estimated_bandwidth(in, estimated_bw);
842 if (ret)
843 return ret;
844
845 /* Initial allocation should be 0 according the spec */
846 ret = usb4_dp_port_allocate_bandwidth(in, 0);
847 if (ret)
848 return ret;
849
850 tb_tunnel_dbg(tunnel, "bandwidth allocation mode enabled\n");
851 return 0;
852 }
853
854 static int tb_dp_init(struct tb_tunnel *tunnel)
855 {
856 struct tb_port *in = tunnel->src_port;
857 struct tb_switch *sw = in->sw;
858 struct tb *tb = in->sw->tb;
859 int ret;
860
861 ret = tb_dp_xchg_caps(tunnel);
862 if (ret)
863 return ret;
864
865 if (!tb_switch_is_usb4(sw))
866 return 0;
867
868 if (!usb4_dp_port_bandwidth_mode_supported(in))
869 return 0;
870
871 tb_tunnel_dbg(tunnel, "bandwidth allocation mode supported\n");
872
873 ret = usb4_dp_port_set_cm_id(in, tb->index);
874 if (ret)
875 return ret;
876
877 return tb_dp_bandwidth_alloc_mode_enable(tunnel);
878 }
879
880 static void tb_dp_deinit(struct tb_tunnel *tunnel)
881 {
882 struct tb_port *in = tunnel->src_port;
883
884 if (!usb4_dp_port_bandwidth_mode_supported(in))
885 return;
886 if (usb4_dp_port_bandwidth_mode_enabled(in)) {
887 usb4_dp_port_set_cm_bandwidth_mode_supported(in, false);
888 tb_tunnel_dbg(tunnel, "bandwidth allocation mode disabled\n");
889 }
890 }
891
892 static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
893 {
894 int ret;
895
896 if (active) {
897 struct tb_path **paths;
898 int last;
899
900 paths = tunnel->paths;
901 last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
902
903 tb_dp_port_set_hops(tunnel->src_port,
904 paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
905 paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
906 paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
907
908 tb_dp_port_set_hops(tunnel->dst_port,
909 paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
910 paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
911 paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
912 } else {
913 tb_dp_port_hpd_clear(tunnel->src_port);
914 tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
915 if (tb_port_is_dpout(tunnel->dst_port))
916 tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
917 }
918
919 ret = tb_dp_port_enable(tunnel->src_port, active);
920 if (ret)
921 return ret;
922
923 if (tb_port_is_dpout(tunnel->dst_port))
924 return tb_dp_port_enable(tunnel->dst_port, active);
925
926 return 0;
927 }
928
929 /**
930 * tb_dp_bandwidth_mode_maximum_bandwidth() - Maximum possible bandwidth
931 * @tunnel: DP tunnel to check
932 * @max_bw_rounded: Maximum bandwidth in Mb/s rounded up to the next granularity
933 *
934 * Returns maximum possible bandwidth for this tunnel in Mb/s.
935 */
936 static int tb_dp_bandwidth_mode_maximum_bandwidth(struct tb_tunnel *tunnel,
937 int *max_bw_rounded)
938 {
939 struct tb_port *in = tunnel->src_port;
940 int ret, rate, lanes, max_bw;
941 u32 cap;
942
943 /*
944 * DP IN adapter DP_LOCAL_CAP gets updated to the lowest AUX
945 * read parameter values so this so we can use this to determine
946 * the maximum possible bandwidth over this link.
947 *
948 * See USB4 v2 spec 1.0 10.4.4.5.
949 */
950 ret = tb_port_read(in, &cap, TB_CFG_PORT,
951 in->cap_adap + DP_LOCAL_CAP, 1);
952 if (ret)
953 return ret;
954
955 rate = tb_dp_cap_get_rate_ext(cap);
956 lanes = tb_dp_cap_get_lanes(cap);
957
958 max_bw = tb_dp_bandwidth(rate, lanes);
959
960 if (max_bw_rounded) {
961 ret = usb4_dp_port_granularity(in);
962 if (ret < 0)
963 return ret;
964 *max_bw_rounded = roundup(max_bw, ret);
965 }
966
967 return max_bw;
968 }
969
970 static int tb_dp_bandwidth_mode_consumed_bandwidth(struct tb_tunnel *tunnel,
971 int *consumed_up,
972 int *consumed_down)
973 {
974 struct tb_port *in = tunnel->src_port;
975 int ret, allocated_bw, max_bw_rounded;
976
977 if (!usb4_dp_port_bandwidth_mode_enabled(in))
978 return -EOPNOTSUPP;
979
980 if (!tunnel->bw_mode)
981 return -EOPNOTSUPP;
982
983 /* Read what was allocated previously if any */
984 ret = usb4_dp_port_allocated_bandwidth(in);
985 if (ret < 0)
986 return ret;
987 allocated_bw = ret;
988
989 ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, &max_bw_rounded);
990 if (ret < 0)
991 return ret;
992 if (allocated_bw == max_bw_rounded)
993 allocated_bw = ret;
994
995 if (tb_tunnel_direction_downstream(tunnel)) {
996 *consumed_up = 0;
997 *consumed_down = allocated_bw;
998 } else {
999 *consumed_up = allocated_bw;
1000 *consumed_down = 0;
1001 }
1002
1003 return 0;
1004 }
1005
1006 static int tb_dp_allocated_bandwidth(struct tb_tunnel *tunnel, int *allocated_up,
1007 int *allocated_down)
1008 {
1009 struct tb_port *in = tunnel->src_port;
1010
1011 /*
1012 * If we have already set the allocated bandwidth then use that.
1013 * Otherwise we read it from the DPRX.
1014 */
1015 if (usb4_dp_port_bandwidth_mode_enabled(in) && tunnel->bw_mode) {
1016 int ret, allocated_bw, max_bw_rounded;
1017
1018 ret = usb4_dp_port_allocated_bandwidth(in);
1019 if (ret < 0)
1020 return ret;
1021 allocated_bw = ret;
1022
1023 ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel,
1024 &max_bw_rounded);
1025 if (ret < 0)
1026 return ret;
1027 if (allocated_bw == max_bw_rounded)
1028 allocated_bw = ret;
1029
1030 if (tb_tunnel_direction_downstream(tunnel)) {
1031 *allocated_up = 0;
1032 *allocated_down = allocated_bw;
1033 } else {
1034 *allocated_up = allocated_bw;
1035 *allocated_down = 0;
1036 }
1037 return 0;
1038 }
1039
1040 return tunnel->consumed_bandwidth(tunnel, allocated_up,
1041 allocated_down);
1042 }
1043
1044 static int tb_dp_alloc_bandwidth(struct tb_tunnel *tunnel, int *alloc_up,
1045 int *alloc_down)
1046 {
1047 struct tb_port *in = tunnel->src_port;
1048 int max_bw_rounded, ret, tmp;
1049
1050 if (!usb4_dp_port_bandwidth_mode_enabled(in))
1051 return -EOPNOTSUPP;
1052
1053 ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, &max_bw_rounded);
1054 if (ret < 0)
1055 return ret;
1056
1057 if (tb_tunnel_direction_downstream(tunnel)) {
1058 tmp = min(*alloc_down, max_bw_rounded);
1059 ret = usb4_dp_port_allocate_bandwidth(in, tmp);
1060 if (ret)
1061 return ret;
1062 *alloc_down = tmp;
1063 *alloc_up = 0;
1064 } else {
1065 tmp = min(*alloc_up, max_bw_rounded);
1066 ret = usb4_dp_port_allocate_bandwidth(in, tmp);
1067 if (ret)
1068 return ret;
1069 *alloc_down = 0;
1070 *alloc_up = tmp;
1071 }
1072
1073 /* Now we can use BW mode registers to figure out the bandwidth */
1074 /* TODO: need to handle discovery too */
1075 tunnel->bw_mode = true;
1076 return 0;
1077 }
1078
1079 static int tb_dp_wait_dprx(struct tb_tunnel *tunnel, int timeout_msec)
1080 {
1081 ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec);
1082 struct tb_port *in = tunnel->src_port;
1083
1084 /*
1085 * Wait for DPRX done. Normally it should be already set for
1086 * active tunnel.
1087 */
1088 do {
1089 u32 val;
1090 int ret;
1091
1092 ret = tb_port_read(in, &val, TB_CFG_PORT,
1093 in->cap_adap + DP_COMMON_CAP, 1);
1094 if (ret)
1095 return ret;
1096
1097 if (val & DP_COMMON_CAP_DPRX_DONE) {
1098 tb_tunnel_dbg(tunnel, "DPRX read done\n");
1099 return 0;
1100 }
1101 usleep_range(100, 150);
1102 } while (ktime_before(ktime_get(), timeout));
1103
1104 tb_tunnel_dbg(tunnel, "DPRX read timeout\n");
1105 return -ETIMEDOUT;
1106 }
1107
1108 /* Read cap from tunnel DP IN */
1109 static int tb_dp_read_cap(struct tb_tunnel *tunnel, unsigned int cap, u32 *rate,
1110 u32 *lanes)
1111 {
1112 struct tb_port *in = tunnel->src_port;
1113 u32 val;
1114 int ret;
1115
1116 switch (cap) {
1117 case DP_LOCAL_CAP:
1118 case DP_REMOTE_CAP:
1119 case DP_COMMON_CAP:
1120 break;
1121
1122 default:
1123 tb_tunnel_WARN(tunnel, "invalid capability index %#x\n", cap);
1124 return -EINVAL;
1125 }
1126
1127 /*
1128 * Read from the copied remote cap so that we take into account
1129 * if capabilities were reduced during exchange.
1130 */
1131 ret = tb_port_read(in, &val, TB_CFG_PORT, in->cap_adap + cap, 1);
1132 if (ret)
1133 return ret;
1134
1135 *rate = tb_dp_cap_get_rate(val);
1136 *lanes = tb_dp_cap_get_lanes(val);
1137 return 0;
1138 }
1139
1140 static int tb_dp_maximum_bandwidth(struct tb_tunnel *tunnel, int *max_up,
1141 int *max_down)
1142 {
1143 int ret;
1144
1145 if (!usb4_dp_port_bandwidth_mode_enabled(tunnel->src_port))
1146 return -EOPNOTSUPP;
1147
1148 ret = tb_dp_bandwidth_mode_maximum_bandwidth(tunnel, NULL);
1149 if (ret < 0)
1150 return ret;
1151
1152 if (tb_tunnel_direction_downstream(tunnel)) {
1153 *max_up = 0;
1154 *max_down = ret;
1155 } else {
1156 *max_up = ret;
1157 *max_down = 0;
1158 }
1159
1160 return 0;
1161 }
1162
1163 static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
1164 int *consumed_down)
1165 {
1166 const struct tb_switch *sw = tunnel->src_port->sw;
1167 u32 rate = 0, lanes = 0;
1168 int ret;
1169
1170 if (tb_dp_is_usb4(sw)) {
1171 /*
1172 * On USB4 routers check if the bandwidth allocation
1173 * mode is enabled first and then read the bandwidth
1174 * through those registers.
1175 */
1176 ret = tb_dp_bandwidth_mode_consumed_bandwidth(tunnel, consumed_up,
1177 consumed_down);
1178 if (ret < 0) {
1179 if (ret != -EOPNOTSUPP)
1180 return ret;
1181 } else if (!ret) {
1182 return 0;
1183 }
1184 /*
1185 * Then see if the DPRX negotiation is ready and if yes
1186 * return that bandwidth (it may be smaller than the
1187 * reduced one). According to VESA spec, the DPRX
1188 * negotiation shall compete in 5 seconds after tunnel
1189 * established. We give it 100ms extra just in case.
1190 */
1191 ret = tb_dp_wait_dprx(tunnel, 5100);
1192 if (ret)
1193 return ret;
1194 ret = tb_dp_read_cap(tunnel, DP_COMMON_CAP, &rate, &lanes);
1195 if (ret)
1196 return ret;
1197 } else if (sw->generation >= 2) {
1198 ret = tb_dp_read_cap(tunnel, DP_REMOTE_CAP, &rate, &lanes);
1199 if (ret)
1200 return ret;
1201 } else {
1202 /* No bandwidth management for legacy devices */
1203 *consumed_up = 0;
1204 *consumed_down = 0;
1205 return 0;
1206 }
1207
1208 if (tb_tunnel_direction_downstream(tunnel)) {
1209 *consumed_up = 0;
1210 *consumed_down = tb_dp_bandwidth(rate, lanes);
1211 } else {
1212 *consumed_up = tb_dp_bandwidth(rate, lanes);
1213 *consumed_down = 0;
1214 }
1215
1216 return 0;
1217 }
1218
1219 static void tb_dp_init_aux_credits(struct tb_path_hop *hop)
1220 {
1221 struct tb_port *port = hop->in_port;
1222 struct tb_switch *sw = port->sw;
1223
1224 if (tb_port_use_credit_allocation(port))
1225 hop->initial_credits = sw->min_dp_aux_credits;
1226 else
1227 hop->initial_credits = 1;
1228 }
1229
1230 static void tb_dp_init_aux_path(struct tb_path *path, bool pm_support)
1231 {
1232 struct tb_path_hop *hop;
1233
1234 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1235 path->egress_shared_buffer = TB_PATH_NONE;
1236 path->ingress_fc_enable = TB_PATH_ALL;
1237 path->ingress_shared_buffer = TB_PATH_NONE;
1238 path->priority = TB_DP_AUX_PRIORITY;
1239 path->weight = TB_DP_AUX_WEIGHT;
1240
1241 tb_path_for_each_hop(path, hop) {
1242 tb_dp_init_aux_credits(hop);
1243 if (pm_support)
1244 tb_init_pm_support(hop);
1245 }
1246 }
1247
1248 static int tb_dp_init_video_credits(struct tb_path_hop *hop)
1249 {
1250 struct tb_port *port = hop->in_port;
1251 struct tb_switch *sw = port->sw;
1252
1253 if (tb_port_use_credit_allocation(port)) {
1254 unsigned int nfc_credits;
1255 size_t max_dp_streams;
1256
1257 tb_available_credits(port, &max_dp_streams);
1258 /*
1259 * Read the number of currently allocated NFC credits
1260 * from the lane adapter. Since we only use them for DP
1261 * tunneling we can use that to figure out how many DP
1262 * tunnels already go through the lane adapter.
1263 */
1264 nfc_credits = port->config.nfc_credits &
1265 ADP_CS_4_NFC_BUFFERS_MASK;
1266 if (nfc_credits / sw->min_dp_main_credits > max_dp_streams)
1267 return -ENOSPC;
1268
1269 hop->nfc_credits = sw->min_dp_main_credits;
1270 } else {
1271 hop->nfc_credits = min(port->total_credits - 2, 12U);
1272 }
1273
1274 return 0;
1275 }
1276
1277 static int tb_dp_init_video_path(struct tb_path *path, bool pm_support)
1278 {
1279 struct tb_path_hop *hop;
1280
1281 path->egress_fc_enable = TB_PATH_NONE;
1282 path->egress_shared_buffer = TB_PATH_NONE;
1283 path->ingress_fc_enable = TB_PATH_NONE;
1284 path->ingress_shared_buffer = TB_PATH_NONE;
1285 path->priority = TB_DP_VIDEO_PRIORITY;
1286 path->weight = TB_DP_VIDEO_WEIGHT;
1287
1288 tb_path_for_each_hop(path, hop) {
1289 int ret;
1290
1291 ret = tb_dp_init_video_credits(hop);
1292 if (ret)
1293 return ret;
1294 if (pm_support)
1295 tb_init_pm_support(hop);
1296 }
1297
1298 return 0;
1299 }
1300
1301 static void tb_dp_dump(struct tb_tunnel *tunnel)
1302 {
1303 struct tb_port *in, *out;
1304 u32 dp_cap, rate, lanes;
1305
1306 in = tunnel->src_port;
1307 out = tunnel->dst_port;
1308
1309 if (tb_port_read(in, &dp_cap, TB_CFG_PORT,
1310 in->cap_adap + DP_LOCAL_CAP, 1))
1311 return;
1312
1313 rate = tb_dp_cap_get_rate(dp_cap);
1314 lanes = tb_dp_cap_get_lanes(dp_cap);
1315
1316 tb_tunnel_dbg(tunnel,
1317 "DP IN maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
1318 rate, lanes, tb_dp_bandwidth(rate, lanes));
1319
1320 if (tb_port_read(out, &dp_cap, TB_CFG_PORT,
1321 out->cap_adap + DP_LOCAL_CAP, 1))
1322 return;
1323
1324 rate = tb_dp_cap_get_rate(dp_cap);
1325 lanes = tb_dp_cap_get_lanes(dp_cap);
1326
1327 tb_tunnel_dbg(tunnel,
1328 "DP OUT maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
1329 rate, lanes, tb_dp_bandwidth(rate, lanes));
1330
1331 if (tb_port_read(in, &dp_cap, TB_CFG_PORT,
1332 in->cap_adap + DP_REMOTE_CAP, 1))
1333 return;
1334
1335 rate = tb_dp_cap_get_rate(dp_cap);
1336 lanes = tb_dp_cap_get_lanes(dp_cap);
1337
1338 tb_tunnel_dbg(tunnel, "reduced bandwidth %u Mb/s x%u = %u Mb/s\n",
1339 rate, lanes, tb_dp_bandwidth(rate, lanes));
1340 }
1341
1342 /**
1343 * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
1344 * @tb: Pointer to the domain structure
1345 * @in: DP in adapter
1346 * @alloc_hopid: Allocate HopIDs from visited ports
1347 *
1348 * If @in adapter is active, follows the tunnel to the DP out adapter
1349 * and back. Returns the discovered tunnel or %NULL if there was no
1350 * tunnel.
1351 *
1352 * Return: DP tunnel or %NULL if no tunnel found.
1353 */
1354 struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
1355 bool alloc_hopid)
1356 {
1357 struct tb_tunnel *tunnel;
1358 struct tb_port *port;
1359 struct tb_path *path;
1360
1361 if (!tb_dp_port_is_enabled(in))
1362 return NULL;
1363
1364 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
1365 if (!tunnel)
1366 return NULL;
1367
1368 tunnel->init = tb_dp_init;
1369 tunnel->deinit = tb_dp_deinit;
1370 tunnel->activate = tb_dp_activate;
1371 tunnel->maximum_bandwidth = tb_dp_maximum_bandwidth;
1372 tunnel->allocated_bandwidth = tb_dp_allocated_bandwidth;
1373 tunnel->alloc_bandwidth = tb_dp_alloc_bandwidth;
1374 tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
1375 tunnel->src_port = in;
1376
1377 path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
1378 &tunnel->dst_port, "Video", alloc_hopid);
1379 if (!path) {
1380 /* Just disable the DP IN port */
1381 tb_dp_port_enable(in, false);
1382 goto err_free;
1383 }
1384 tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
1385 if (tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], false))
1386 goto err_free;
1387
1388 path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX",
1389 alloc_hopid);
1390 if (!path)
1391 goto err_deactivate;
1392 tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
1393 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT], false);
1394
1395 path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
1396 &port, "AUX RX", alloc_hopid);
1397 if (!path)
1398 goto err_deactivate;
1399 tunnel->paths[TB_DP_AUX_PATH_IN] = path;
1400 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN], false);
1401
1402 /* Validate that the tunnel is complete */
1403 if (!tb_port_is_dpout(tunnel->dst_port)) {
1404 tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
1405 goto err_deactivate;
1406 }
1407
1408 if (!tb_dp_port_is_enabled(tunnel->dst_port))
1409 goto err_deactivate;
1410
1411 if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
1412 goto err_deactivate;
1413
1414 if (port != tunnel->src_port) {
1415 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
1416 goto err_deactivate;
1417 }
1418
1419 tb_dp_dump(tunnel);
1420
1421 tb_tunnel_dbg(tunnel, "discovered\n");
1422 return tunnel;
1423
1424 err_deactivate:
1425 tb_tunnel_deactivate(tunnel);
1426 err_free:
1427 tb_tunnel_free(tunnel);
1428
1429 return NULL;
1430 }
1431
1432 /**
1433 * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
1434 * @tb: Pointer to the domain structure
1435 * @in: DP in adapter port
1436 * @out: DP out adapter port
1437 * @link_nr: Preferred lane adapter when the link is not bonded
1438 * @max_up: Maximum available upstream bandwidth for the DP tunnel.
1439 * %0 if no available bandwidth.
1440 * @max_down: Maximum available downstream bandwidth for the DP tunnel.
1441 * %0 if no available bandwidth.
1442 *
1443 * Allocates a tunnel between @in and @out that is capable of tunneling
1444 * Display Port traffic.
1445 *
1446 * Return: Returns a tb_tunnel on success or NULL on failure.
1447 */
1448 struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
1449 struct tb_port *out, int link_nr,
1450 int max_up, int max_down)
1451 {
1452 struct tb_tunnel *tunnel;
1453 struct tb_path **paths;
1454 struct tb_path *path;
1455 bool pm_support;
1456
1457 if (WARN_ON(!in->cap_adap || !out->cap_adap))
1458 return NULL;
1459
1460 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
1461 if (!tunnel)
1462 return NULL;
1463
1464 tunnel->init = tb_dp_init;
1465 tunnel->deinit = tb_dp_deinit;
1466 tunnel->activate = tb_dp_activate;
1467 tunnel->maximum_bandwidth = tb_dp_maximum_bandwidth;
1468 tunnel->allocated_bandwidth = tb_dp_allocated_bandwidth;
1469 tunnel->alloc_bandwidth = tb_dp_alloc_bandwidth;
1470 tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
1471 tunnel->src_port = in;
1472 tunnel->dst_port = out;
1473 tunnel->max_up = max_up;
1474 tunnel->max_down = max_down;
1475
1476 paths = tunnel->paths;
1477 pm_support = usb4_switch_version(in->sw) >= 2;
1478
1479 path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
1480 link_nr, "Video");
1481 if (!path)
1482 goto err_free;
1483 tb_dp_init_video_path(path, pm_support);
1484 paths[TB_DP_VIDEO_PATH_OUT] = path;
1485
1486 path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
1487 TB_DP_AUX_TX_HOPID, link_nr, "AUX TX");
1488 if (!path)
1489 goto err_free;
1490 tb_dp_init_aux_path(path, pm_support);
1491 paths[TB_DP_AUX_PATH_OUT] = path;
1492
1493 path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
1494 TB_DP_AUX_RX_HOPID, link_nr, "AUX RX");
1495 if (!path)
1496 goto err_free;
1497 tb_dp_init_aux_path(path, pm_support);
1498 paths[TB_DP_AUX_PATH_IN] = path;
1499
1500 return tunnel;
1501
1502 err_free:
1503 tb_tunnel_free(tunnel);
1504 return NULL;
1505 }
1506
1507 static unsigned int tb_dma_available_credits(const struct tb_port *port)
1508 {
1509 const struct tb_switch *sw = port->sw;
1510 int credits;
1511
1512 credits = tb_available_credits(port, NULL);
1513 if (tb_acpi_may_tunnel_pcie())
1514 credits -= sw->max_pcie_credits;
1515 credits -= port->dma_credits;
1516
1517 return credits > 0 ? credits : 0;
1518 }
1519
1520 static int tb_dma_reserve_credits(struct tb_path_hop *hop, unsigned int credits)
1521 {
1522 struct tb_port *port = hop->in_port;
1523
1524 if (tb_port_use_credit_allocation(port)) {
1525 unsigned int available = tb_dma_available_credits(port);
1526
1527 /*
1528 * Need to have at least TB_MIN_DMA_CREDITS, otherwise
1529 * DMA path cannot be established.
1530 */
1531 if (available < TB_MIN_DMA_CREDITS)
1532 return -ENOSPC;
1533
1534 while (credits > available)
1535 credits--;
1536
1537 tb_port_dbg(port, "reserving %u credits for DMA path\n",
1538 credits);
1539
1540 port->dma_credits += credits;
1541 } else {
1542 if (tb_port_is_null(port))
1543 credits = port->bonded ? 14 : 6;
1544 else
1545 credits = min(port->total_credits, credits);
1546 }
1547
1548 hop->initial_credits = credits;
1549 return 0;
1550 }
1551
1552 /* Path from lane adapter to NHI */
1553 static int tb_dma_init_rx_path(struct tb_path *path, unsigned int credits)
1554 {
1555 struct tb_path_hop *hop;
1556 unsigned int i, tmp;
1557
1558 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1559 path->ingress_fc_enable = TB_PATH_ALL;
1560 path->egress_shared_buffer = TB_PATH_NONE;
1561 path->ingress_shared_buffer = TB_PATH_NONE;
1562 path->priority = TB_DMA_PRIORITY;
1563 path->weight = TB_DMA_WEIGHT;
1564 path->clear_fc = true;
1565
1566 /*
1567 * First lane adapter is the one connected to the remote host.
1568 * We don't tunnel other traffic over this link so can use all
1569 * the credits (except the ones reserved for control traffic).
1570 */
1571 hop = &path->hops[0];
1572 tmp = min(tb_usable_credits(hop->in_port), credits);
1573 hop->initial_credits = tmp;
1574 hop->in_port->dma_credits += tmp;
1575
1576 for (i = 1; i < path->path_length; i++) {
1577 int ret;
1578
1579 ret = tb_dma_reserve_credits(&path->hops[i], credits);
1580 if (ret)
1581 return ret;
1582 }
1583
1584 return 0;
1585 }
1586
1587 /* Path from NHI to lane adapter */
1588 static int tb_dma_init_tx_path(struct tb_path *path, unsigned int credits)
1589 {
1590 struct tb_path_hop *hop;
1591
1592 path->egress_fc_enable = TB_PATH_ALL;
1593 path->ingress_fc_enable = TB_PATH_ALL;
1594 path->egress_shared_buffer = TB_PATH_NONE;
1595 path->ingress_shared_buffer = TB_PATH_NONE;
1596 path->priority = TB_DMA_PRIORITY;
1597 path->weight = TB_DMA_WEIGHT;
1598 path->clear_fc = true;
1599
1600 tb_path_for_each_hop(path, hop) {
1601 int ret;
1602
1603 ret = tb_dma_reserve_credits(hop, credits);
1604 if (ret)
1605 return ret;
1606 }
1607
1608 return 0;
1609 }
1610
1611 static void tb_dma_release_credits(struct tb_path_hop *hop)
1612 {
1613 struct tb_port *port = hop->in_port;
1614
1615 if (tb_port_use_credit_allocation(port)) {
1616 port->dma_credits -= hop->initial_credits;
1617
1618 tb_port_dbg(port, "released %u DMA path credits\n",
1619 hop->initial_credits);
1620 }
1621 }
1622
1623 static void tb_dma_deinit_path(struct tb_path *path)
1624 {
1625 struct tb_path_hop *hop;
1626
1627 tb_path_for_each_hop(path, hop)
1628 tb_dma_release_credits(hop);
1629 }
1630
1631 static void tb_dma_deinit(struct tb_tunnel *tunnel)
1632 {
1633 int i;
1634
1635 for (i = 0; i < tunnel->npaths; i++) {
1636 if (!tunnel->paths[i])
1637 continue;
1638 tb_dma_deinit_path(tunnel->paths[i]);
1639 }
1640 }
1641
1642 /**
1643 * tb_tunnel_alloc_dma() - allocate a DMA tunnel
1644 * @tb: Pointer to the domain structure
1645 * @nhi: Host controller port
1646 * @dst: Destination null port which the other domain is connected to
1647 * @transmit_path: HopID used for transmitting packets
1648 * @transmit_ring: NHI ring number used to send packets towards the
1649 * other domain. Set to %-1 if TX path is not needed.
1650 * @receive_path: HopID used for receiving packets
1651 * @receive_ring: NHI ring number used to receive packets from the
1652 * other domain. Set to %-1 if RX path is not needed.
1653 *
1654 * Return: Returns a tb_tunnel on success or NULL on failure.
1655 */
1656 struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
1657 struct tb_port *dst, int transmit_path,
1658 int transmit_ring, int receive_path,
1659 int receive_ring)
1660 {
1661 struct tb_tunnel *tunnel;
1662 size_t npaths = 0, i = 0;
1663 struct tb_path *path;
1664 int credits;
1665
1666 /* Ring 0 is reserved for control channel */
1667 if (WARN_ON(!receive_ring || !transmit_ring))
1668 return NULL;
1669
1670 if (receive_ring > 0)
1671 npaths++;
1672 if (transmit_ring > 0)
1673 npaths++;
1674
1675 if (WARN_ON(!npaths))
1676 return NULL;
1677
1678 tunnel = tb_tunnel_alloc(tb, npaths, TB_TUNNEL_DMA);
1679 if (!tunnel)
1680 return NULL;
1681
1682 tunnel->src_port = nhi;
1683 tunnel->dst_port = dst;
1684 tunnel->deinit = tb_dma_deinit;
1685
1686 credits = min_not_zero(dma_credits, nhi->sw->max_dma_credits);
1687
1688 if (receive_ring > 0) {
1689 path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0,
1690 "DMA RX");
1691 if (!path)
1692 goto err_free;
1693 tunnel->paths[i++] = path;
1694 if (tb_dma_init_rx_path(path, credits)) {
1695 tb_tunnel_dbg(tunnel, "not enough buffers for RX path\n");
1696 goto err_free;
1697 }
1698 }
1699
1700 if (transmit_ring > 0) {
1701 path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0,
1702 "DMA TX");
1703 if (!path)
1704 goto err_free;
1705 tunnel->paths[i++] = path;
1706 if (tb_dma_init_tx_path(path, credits)) {
1707 tb_tunnel_dbg(tunnel, "not enough buffers for TX path\n");
1708 goto err_free;
1709 }
1710 }
1711
1712 return tunnel;
1713
1714 err_free:
1715 tb_tunnel_free(tunnel);
1716 return NULL;
1717 }
1718
1719 /**
1720 * tb_tunnel_match_dma() - Match DMA tunnel
1721 * @tunnel: Tunnel to match
1722 * @transmit_path: HopID used for transmitting packets. Pass %-1 to ignore.
1723 * @transmit_ring: NHI ring number used to send packets towards the
1724 * other domain. Pass %-1 to ignore.
1725 * @receive_path: HopID used for receiving packets. Pass %-1 to ignore.
1726 * @receive_ring: NHI ring number used to receive packets from the
1727 * other domain. Pass %-1 to ignore.
1728 *
1729 * This function can be used to match specific DMA tunnel, if there are
1730 * multiple DMA tunnels going through the same XDomain connection.
1731 * Returns true if there is match and false otherwise.
1732 */
1733 bool tb_tunnel_match_dma(const struct tb_tunnel *tunnel, int transmit_path,
1734 int transmit_ring, int receive_path, int receive_ring)
1735 {
1736 const struct tb_path *tx_path = NULL, *rx_path = NULL;
1737 int i;
1738
1739 if (!receive_ring || !transmit_ring)
1740 return false;
1741
1742 for (i = 0; i < tunnel->npaths; i++) {
1743 const struct tb_path *path = tunnel->paths[i];
1744
1745 if (!path)
1746 continue;
1747
1748 if (tb_port_is_nhi(path->hops[0].in_port))
1749 tx_path = path;
1750 else if (tb_port_is_nhi(path->hops[path->path_length - 1].out_port))
1751 rx_path = path;
1752 }
1753
1754 if (transmit_ring > 0 || transmit_path > 0) {
1755 if (!tx_path)
1756 return false;
1757 if (transmit_ring > 0 &&
1758 (tx_path->hops[0].in_hop_index != transmit_ring))
1759 return false;
1760 if (transmit_path > 0 &&
1761 (tx_path->hops[tx_path->path_length - 1].next_hop_index != transmit_path))
1762 return false;
1763 }
1764
1765 if (receive_ring > 0 || receive_path > 0) {
1766 if (!rx_path)
1767 return false;
1768 if (receive_path > 0 &&
1769 (rx_path->hops[0].in_hop_index != receive_path))
1770 return false;
1771 if (receive_ring > 0 &&
1772 (rx_path->hops[rx_path->path_length - 1].next_hop_index != receive_ring))
1773 return false;
1774 }
1775
1776 return true;
1777 }
1778
1779 static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down)
1780 {
1781 int ret, up_max_rate, down_max_rate;
1782
1783 ret = usb4_usb3_port_max_link_rate(up);
1784 if (ret < 0)
1785 return ret;
1786 up_max_rate = ret;
1787
1788 ret = usb4_usb3_port_max_link_rate(down);
1789 if (ret < 0)
1790 return ret;
1791 down_max_rate = ret;
1792
1793 return min(up_max_rate, down_max_rate);
1794 }
1795
1796 static int tb_usb3_init(struct tb_tunnel *tunnel)
1797 {
1798 tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n",
1799 tunnel->allocated_up, tunnel->allocated_down);
1800
1801 return usb4_usb3_port_allocate_bandwidth(tunnel->src_port,
1802 &tunnel->allocated_up,
1803 &tunnel->allocated_down);
1804 }
1805
1806 static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate)
1807 {
1808 int res;
1809
1810 res = tb_usb3_port_enable(tunnel->src_port, activate);
1811 if (res)
1812 return res;
1813
1814 if (tb_port_is_usb3_up(tunnel->dst_port))
1815 return tb_usb3_port_enable(tunnel->dst_port, activate);
1816
1817 return 0;
1818 }
1819
1820 static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel,
1821 int *consumed_up, int *consumed_down)
1822 {
1823 struct tb_port *port = tb_upstream_port(tunnel->dst_port->sw);
1824 int pcie_weight = tb_acpi_may_tunnel_pcie() ? TB_PCI_WEIGHT : 0;
1825
1826 /*
1827 * PCIe tunneling, if enabled, affects the USB3 bandwidth so
1828 * take that it into account here.
1829 */
1830 *consumed_up = tunnel->allocated_up *
1831 (TB_USB3_WEIGHT + pcie_weight) / TB_USB3_WEIGHT;
1832 *consumed_down = tunnel->allocated_down *
1833 (TB_USB3_WEIGHT + pcie_weight) / TB_USB3_WEIGHT;
1834
1835 if (tb_port_get_link_generation(port) >= 4) {
1836 *consumed_up = max(*consumed_up, USB4_V2_USB3_MIN_BANDWIDTH);
1837 *consumed_down = max(*consumed_down, USB4_V2_USB3_MIN_BANDWIDTH);
1838 }
1839
1840 return 0;
1841 }
1842
1843 static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel)
1844 {
1845 int ret;
1846
1847 ret = usb4_usb3_port_release_bandwidth(tunnel->src_port,
1848 &tunnel->allocated_up,
1849 &tunnel->allocated_down);
1850 if (ret)
1851 return ret;
1852
1853 tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n",
1854 tunnel->allocated_up, tunnel->allocated_down);
1855 return 0;
1856 }
1857
1858 static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
1859 int *available_up,
1860 int *available_down)
1861 {
1862 int ret, max_rate, allocate_up, allocate_down;
1863
1864 ret = tb_usb3_max_link_rate(tunnel->dst_port, tunnel->src_port);
1865 if (ret < 0) {
1866 tb_tunnel_warn(tunnel, "failed to read maximum link rate\n");
1867 return;
1868 }
1869
1870 /*
1871 * 90% of the max rate can be allocated for isochronous
1872 * transfers.
1873 */
1874 max_rate = ret * 90 / 100;
1875
1876 /* No need to reclaim if already at maximum */
1877 if (tunnel->allocated_up >= max_rate &&
1878 tunnel->allocated_down >= max_rate)
1879 return;
1880
1881 /* Don't go lower than what is already allocated */
1882 allocate_up = min(max_rate, *available_up);
1883 if (allocate_up < tunnel->allocated_up)
1884 allocate_up = tunnel->allocated_up;
1885
1886 allocate_down = min(max_rate, *available_down);
1887 if (allocate_down < tunnel->allocated_down)
1888 allocate_down = tunnel->allocated_down;
1889
1890 /* If no changes no need to do more */
1891 if (allocate_up == tunnel->allocated_up &&
1892 allocate_down == tunnel->allocated_down)
1893 return;
1894
1895 ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up,
1896 &allocate_down);
1897 if (ret) {
1898 tb_tunnel_info(tunnel, "failed to allocate bandwidth\n");
1899 return;
1900 }
1901
1902 tunnel->allocated_up = allocate_up;
1903 *available_up -= tunnel->allocated_up;
1904
1905 tunnel->allocated_down = allocate_down;
1906 *available_down -= tunnel->allocated_down;
1907
1908 tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n",
1909 tunnel->allocated_up, tunnel->allocated_down);
1910 }
1911
1912 static void tb_usb3_init_credits(struct tb_path_hop *hop)
1913 {
1914 struct tb_port *port = hop->in_port;
1915 struct tb_switch *sw = port->sw;
1916 unsigned int credits;
1917
1918 if (tb_port_use_credit_allocation(port)) {
1919 credits = sw->max_usb3_credits;
1920 } else {
1921 if (tb_port_is_null(port))
1922 credits = port->bonded ? 32 : 16;
1923 else
1924 credits = 7;
1925 }
1926
1927 hop->initial_credits = credits;
1928 }
1929
1930 static void tb_usb3_init_path(struct tb_path *path)
1931 {
1932 struct tb_path_hop *hop;
1933
1934 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1935 path->egress_shared_buffer = TB_PATH_NONE;
1936 path->ingress_fc_enable = TB_PATH_ALL;
1937 path->ingress_shared_buffer = TB_PATH_NONE;
1938 path->priority = TB_USB3_PRIORITY;
1939 path->weight = TB_USB3_WEIGHT;
1940 path->drop_packages = 0;
1941
1942 tb_path_for_each_hop(path, hop)
1943 tb_usb3_init_credits(hop);
1944 }
1945
1946 /**
1947 * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
1948 * @tb: Pointer to the domain structure
1949 * @down: USB3 downstream adapter
1950 * @alloc_hopid: Allocate HopIDs from visited ports
1951 *
1952 * If @down adapter is active, follows the tunnel to the USB3 upstream
1953 * adapter and back. Returns the discovered tunnel or %NULL if there was
1954 * no tunnel.
1955 */
1956 struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down,
1957 bool alloc_hopid)
1958 {
1959 struct tb_tunnel *tunnel;
1960 struct tb_path *path;
1961
1962 if (!tb_usb3_port_is_enabled(down))
1963 return NULL;
1964
1965 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1966 if (!tunnel)
1967 return NULL;
1968
1969 tunnel->activate = tb_usb3_activate;
1970 tunnel->src_port = down;
1971
1972 /*
1973 * Discover both paths even if they are not complete. We will
1974 * clean them up by calling tb_tunnel_deactivate() below in that
1975 * case.
1976 */
1977 path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
1978 &tunnel->dst_port, "USB3 Down", alloc_hopid);
1979 if (!path) {
1980 /* Just disable the downstream port */
1981 tb_usb3_port_enable(down, false);
1982 goto err_free;
1983 }
1984 tunnel->paths[TB_USB3_PATH_DOWN] = path;
1985 tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
1986
1987 path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
1988 "USB3 Up", alloc_hopid);
1989 if (!path)
1990 goto err_deactivate;
1991 tunnel->paths[TB_USB3_PATH_UP] = path;
1992 tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]);
1993
1994 /* Validate that the tunnel is complete */
1995 if (!tb_port_is_usb3_up(tunnel->dst_port)) {
1996 tb_port_warn(tunnel->dst_port,
1997 "path does not end on an USB3 adapter, cleaning up\n");
1998 goto err_deactivate;
1999 }
2000
2001 if (down != tunnel->src_port) {
2002 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
2003 goto err_deactivate;
2004 }
2005
2006 if (!tb_usb3_port_is_enabled(tunnel->dst_port)) {
2007 tb_tunnel_warn(tunnel,
2008 "tunnel is not fully activated, cleaning up\n");
2009 goto err_deactivate;
2010 }
2011
2012 if (!tb_route(down->sw)) {
2013 int ret;
2014
2015 /*
2016 * Read the initial bandwidth allocation for the first
2017 * hop tunnel.
2018 */
2019 ret = usb4_usb3_port_allocated_bandwidth(down,
2020 &tunnel->allocated_up, &tunnel->allocated_down);
2021 if (ret)
2022 goto err_deactivate;
2023
2024 tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n",
2025 tunnel->allocated_up, tunnel->allocated_down);
2026
2027 tunnel->init = tb_usb3_init;
2028 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
2029 tunnel->release_unused_bandwidth =
2030 tb_usb3_release_unused_bandwidth;
2031 tunnel->reclaim_available_bandwidth =
2032 tb_usb3_reclaim_available_bandwidth;
2033 }
2034
2035 tb_tunnel_dbg(tunnel, "discovered\n");
2036 return tunnel;
2037
2038 err_deactivate:
2039 tb_tunnel_deactivate(tunnel);
2040 err_free:
2041 tb_tunnel_free(tunnel);
2042
2043 return NULL;
2044 }
2045
2046 /**
2047 * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel
2048 * @tb: Pointer to the domain structure
2049 * @up: USB3 upstream adapter port
2050 * @down: USB3 downstream adapter port
2051 * @max_up: Maximum available upstream bandwidth for the USB3 tunnel.
2052 * %0 if no available bandwidth.
2053 * @max_down: Maximum available downstream bandwidth for the USB3 tunnel.
2054 * %0 if no available bandwidth.
2055 *
2056 * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and
2057 * @TB_TYPE_USB3_DOWN.
2058 *
2059 * Return: Returns a tb_tunnel on success or %NULL on failure.
2060 */
2061 struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
2062 struct tb_port *down, int max_up,
2063 int max_down)
2064 {
2065 struct tb_tunnel *tunnel;
2066 struct tb_path *path;
2067 int max_rate = 0;
2068
2069 if (!tb_route(down->sw) && (max_up > 0 || max_down > 0)) {
2070 /*
2071 * For USB3 isochronous transfers, we allow bandwidth which is
2072 * not higher than 90% of maximum supported bandwidth by USB3
2073 * adapters.
2074 */
2075 max_rate = tb_usb3_max_link_rate(down, up);
2076 if (max_rate < 0)
2077 return NULL;
2078
2079 max_rate = max_rate * 90 / 100;
2080 tb_port_dbg(up, "maximum required bandwidth for USB3 tunnel %d Mb/s\n",
2081 max_rate);
2082 }
2083
2084 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
2085 if (!tunnel)
2086 return NULL;
2087
2088 tunnel->activate = tb_usb3_activate;
2089 tunnel->src_port = down;
2090 tunnel->dst_port = up;
2091 tunnel->max_up = max_up;
2092 tunnel->max_down = max_down;
2093
2094 path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0,
2095 "USB3 Down");
2096 if (!path) {
2097 tb_tunnel_free(tunnel);
2098 return NULL;
2099 }
2100 tb_usb3_init_path(path);
2101 tunnel->paths[TB_USB3_PATH_DOWN] = path;
2102
2103 path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0,
2104 "USB3 Up");
2105 if (!path) {
2106 tb_tunnel_free(tunnel);
2107 return NULL;
2108 }
2109 tb_usb3_init_path(path);
2110 tunnel->paths[TB_USB3_PATH_UP] = path;
2111
2112 if (!tb_route(down->sw)) {
2113 tunnel->allocated_up = min(max_rate, max_up);
2114 tunnel->allocated_down = min(max_rate, max_down);
2115
2116 tunnel->init = tb_usb3_init;
2117 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
2118 tunnel->release_unused_bandwidth =
2119 tb_usb3_release_unused_bandwidth;
2120 tunnel->reclaim_available_bandwidth =
2121 tb_usb3_reclaim_available_bandwidth;
2122 }
2123
2124 return tunnel;
2125 }
2126
2127 /**
2128 * tb_tunnel_free() - free a tunnel
2129 * @tunnel: Tunnel to be freed
2130 *
2131 * Frees a tunnel. The tunnel does not need to be deactivated.
2132 */
2133 void tb_tunnel_free(struct tb_tunnel *tunnel)
2134 {
2135 int i;
2136
2137 if (!tunnel)
2138 return;
2139
2140 if (tunnel->deinit)
2141 tunnel->deinit(tunnel);
2142
2143 for (i = 0; i < tunnel->npaths; i++) {
2144 if (tunnel->paths[i])
2145 tb_path_free(tunnel->paths[i]);
2146 }
2147
2148 kfree(tunnel->paths);
2149 kfree(tunnel);
2150 }
2151
2152 /**
2153 * tb_tunnel_is_invalid - check whether an activated path is still valid
2154 * @tunnel: Tunnel to check
2155 */
2156 bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
2157 {
2158 int i;
2159
2160 for (i = 0; i < tunnel->npaths; i++) {
2161 WARN_ON(!tunnel->paths[i]->activated);
2162 if (tb_path_is_invalid(tunnel->paths[i]))
2163 return true;
2164 }
2165
2166 return false;
2167 }
2168
2169 /**
2170 * tb_tunnel_restart() - activate a tunnel after a hardware reset
2171 * @tunnel: Tunnel to restart
2172 *
2173 * Return: 0 on success and negative errno in case if failure
2174 */
2175 int tb_tunnel_restart(struct tb_tunnel *tunnel)
2176 {
2177 int res, i;
2178
2179 tb_tunnel_dbg(tunnel, "activating\n");
2180
2181 /*
2182 * Make sure all paths are properly disabled before enabling
2183 * them again.
2184 */
2185 for (i = 0; i < tunnel->npaths; i++) {
2186 if (tunnel->paths[i]->activated) {
2187 tb_path_deactivate(tunnel->paths[i]);
2188 tunnel->paths[i]->activated = false;
2189 }
2190 }
2191
2192 if (tunnel->init) {
2193 res = tunnel->init(tunnel);
2194 if (res)
2195 return res;
2196 }
2197
2198 for (i = 0; i < tunnel->npaths; i++) {
2199 res = tb_path_activate(tunnel->paths[i]);
2200 if (res)
2201 goto err;
2202 }
2203
2204 if (tunnel->activate) {
2205 res = tunnel->activate(tunnel, true);
2206 if (res)
2207 goto err;
2208 }
2209
2210 return 0;
2211
2212 err:
2213 tb_tunnel_warn(tunnel, "activation failed\n");
2214 tb_tunnel_deactivate(tunnel);
2215 return res;
2216 }
2217
2218 /**
2219 * tb_tunnel_activate() - activate a tunnel
2220 * @tunnel: Tunnel to activate
2221 *
2222 * Return: Returns 0 on success or an error code on failure.
2223 */
2224 int tb_tunnel_activate(struct tb_tunnel *tunnel)
2225 {
2226 int i;
2227
2228 for (i = 0; i < tunnel->npaths; i++) {
2229 if (tunnel->paths[i]->activated) {
2230 tb_tunnel_WARN(tunnel,
2231 "trying to activate an already activated tunnel\n");
2232 return -EINVAL;
2233 }
2234 }
2235
2236 return tb_tunnel_restart(tunnel);
2237 }
2238
2239 /**
2240 * tb_tunnel_deactivate() - deactivate a tunnel
2241 * @tunnel: Tunnel to deactivate
2242 */
2243 void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
2244 {
2245 int i;
2246
2247 tb_tunnel_dbg(tunnel, "deactivating\n");
2248
2249 if (tunnel->activate)
2250 tunnel->activate(tunnel, false);
2251
2252 for (i = 0; i < tunnel->npaths; i++) {
2253 if (tunnel->paths[i] && tunnel->paths[i]->activated)
2254 tb_path_deactivate(tunnel->paths[i]);
2255 }
2256 }
2257
2258 /**
2259 * tb_tunnel_port_on_path() - Does the tunnel go through port
2260 * @tunnel: Tunnel to check
2261 * @port: Port to check
2262 *
2263 * Returns true if @tunnel goes through @port (direction does not matter),
2264 * false otherwise.
2265 */
2266 bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
2267 const struct tb_port *port)
2268 {
2269 int i;
2270
2271 for (i = 0; i < tunnel->npaths; i++) {
2272 if (!tunnel->paths[i])
2273 continue;
2274
2275 if (tb_path_port_on_path(tunnel->paths[i], port))
2276 return true;
2277 }
2278
2279 return false;
2280 }
2281
2282 static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
2283 {
2284 int i;
2285
2286 for (i = 0; i < tunnel->npaths; i++) {
2287 if (!tunnel->paths[i])
2288 return false;
2289 if (!tunnel->paths[i]->activated)
2290 return false;
2291 }
2292
2293 return true;
2294 }
2295
2296 /**
2297 * tb_tunnel_maximum_bandwidth() - Return maximum possible bandwidth
2298 * @tunnel: Tunnel to check
2299 * @max_up: Maximum upstream bandwidth in Mb/s
2300 * @max_down: Maximum downstream bandwidth in Mb/s
2301 *
2302 * Returns maximum possible bandwidth this tunnel can go if not limited
2303 * by other bandwidth clients. If the tunnel does not support this
2304 * returns %-EOPNOTSUPP.
2305 */
2306 int tb_tunnel_maximum_bandwidth(struct tb_tunnel *tunnel, int *max_up,
2307 int *max_down)
2308 {
2309 if (!tb_tunnel_is_active(tunnel))
2310 return -EINVAL;
2311
2312 if (tunnel->maximum_bandwidth)
2313 return tunnel->maximum_bandwidth(tunnel, max_up, max_down);
2314 return -EOPNOTSUPP;
2315 }
2316
2317 /**
2318 * tb_tunnel_allocated_bandwidth() - Return bandwidth allocated for the tunnel
2319 * @tunnel: Tunnel to check
2320 * @allocated_up: Currently allocated upstream bandwidth in Mb/s is stored here
2321 * @allocated_down: Currently allocated downstream bandwidth in Mb/s is
2322 * stored here
2323 *
2324 * Returns the bandwidth allocated for the tunnel. This may be higher
2325 * than what the tunnel actually consumes.
2326 */
2327 int tb_tunnel_allocated_bandwidth(struct tb_tunnel *tunnel, int *allocated_up,
2328 int *allocated_down)
2329 {
2330 if (!tb_tunnel_is_active(tunnel))
2331 return -EINVAL;
2332
2333 if (tunnel->allocated_bandwidth)
2334 return tunnel->allocated_bandwidth(tunnel, allocated_up,
2335 allocated_down);
2336 return -EOPNOTSUPP;
2337 }
2338
2339 /**
2340 * tb_tunnel_alloc_bandwidth() - Change tunnel bandwidth allocation
2341 * @tunnel: Tunnel whose bandwidth allocation to change
2342 * @alloc_up: New upstream bandwidth in Mb/s
2343 * @alloc_down: New downstream bandwidth in Mb/s
2344 *
2345 * Tries to change tunnel bandwidth allocation. If succeeds returns %0
2346 * and updates @alloc_up and @alloc_down to that was actually allocated
2347 * (it may not be the same as passed originally). Returns negative errno
2348 * in case of failure.
2349 */
2350 int tb_tunnel_alloc_bandwidth(struct tb_tunnel *tunnel, int *alloc_up,
2351 int *alloc_down)
2352 {
2353 if (!tb_tunnel_is_active(tunnel))
2354 return -EINVAL;
2355
2356 if (tunnel->alloc_bandwidth)
2357 return tunnel->alloc_bandwidth(tunnel, alloc_up, alloc_down);
2358
2359 return -EOPNOTSUPP;
2360 }
2361
2362 /**
2363 * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
2364 * @tunnel: Tunnel to check
2365 * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port.
2366 * Can be %NULL.
2367 * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port.
2368 * Can be %NULL.
2369 *
2370 * Stores the amount of isochronous bandwidth @tunnel consumes in
2371 * @consumed_up and @consumed_down. In case of success returns %0,
2372 * negative errno otherwise.
2373 */
2374 int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
2375 int *consumed_down)
2376 {
2377 int up_bw = 0, down_bw = 0;
2378
2379 if (!tb_tunnel_is_active(tunnel))
2380 goto out;
2381
2382 if (tunnel->consumed_bandwidth) {
2383 int ret;
2384
2385 ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw);
2386 if (ret)
2387 return ret;
2388
2389 tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw,
2390 down_bw);
2391 }
2392
2393 out:
2394 if (consumed_up)
2395 *consumed_up = up_bw;
2396 if (consumed_down)
2397 *consumed_down = down_bw;
2398
2399 return 0;
2400 }
2401
2402 /**
2403 * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth
2404 * @tunnel: Tunnel whose unused bandwidth to release
2405 *
2406 * If tunnel supports dynamic bandwidth management (USB3 tunnels at the
2407 * moment) this function makes it to release all the unused bandwidth.
2408 *
2409 * Returns %0 in case of success and negative errno otherwise.
2410 */
2411 int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel)
2412 {
2413 if (!tb_tunnel_is_active(tunnel))
2414 return 0;
2415
2416 if (tunnel->release_unused_bandwidth) {
2417 int ret;
2418
2419 ret = tunnel->release_unused_bandwidth(tunnel);
2420 if (ret)
2421 return ret;
2422 }
2423
2424 return 0;
2425 }
2426
2427 /**
2428 * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth
2429 * @tunnel: Tunnel reclaiming available bandwidth
2430 * @available_up: Available upstream bandwidth (in Mb/s)
2431 * @available_down: Available downstream bandwidth (in Mb/s)
2432 *
2433 * Reclaims bandwidth from @available_up and @available_down and updates
2434 * the variables accordingly (e.g decreases both according to what was
2435 * reclaimed by the tunnel). If nothing was reclaimed the values are
2436 * kept as is.
2437 */
2438 void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
2439 int *available_up,
2440 int *available_down)
2441 {
2442 if (!tb_tunnel_is_active(tunnel))
2443 return;
2444
2445 if (tunnel->reclaim_available_bandwidth)
2446 tunnel->reclaim_available_bandwidth(tunnel, available_up,
2447 available_down);
2448 }
2449
2450 const char *tb_tunnel_type_name(const struct tb_tunnel *tunnel)
2451 {
2452 return tb_tunnel_names[tunnel->type];
2453 }
Kernel DRM miscellaneous fixes and cross-tree changes