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 /* Minimum number of credits needed for PCIe path */
38 #define TB_MIN_PCIE_CREDITS 6U
39 /*
40 * Number of credits we try to allocate for each DMA path if not limited
41 * by the host router baMaxHI.
42 */
43 #define TB_DMA_CREDITS 14U
44 /* Minimum number of credits for DMA path */
45 #define TB_MIN_DMA_CREDITS 1U
46
47 static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };
48
49 #define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...) \
50 do { \
51 struct tb_tunnel *__tunnel = (tunnel); \
52 level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt, \
53 tb_route(__tunnel->src_port->sw), \
54 __tunnel->src_port->port, \
55 tb_route(__tunnel->dst_port->sw), \
56 __tunnel->dst_port->port, \
57 tb_tunnel_names[__tunnel->type], \
58 ## arg); \
59 } while (0)
60
61 #define tb_tunnel_WARN(tunnel, fmt, arg...) \
62 __TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
63 #define tb_tunnel_warn(tunnel, fmt, arg...) \
64 __TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
65 #define tb_tunnel_info(tunnel, fmt, arg...) \
66 __TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
67 #define tb_tunnel_dbg(tunnel, fmt, arg...) \
68 __TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
69
tb_usable_credits(const struct tb_port * port)70 static inline unsigned int tb_usable_credits(const struct tb_port *port)
71 {
72 return port->total_credits - port->ctl_credits;
73 }
74
75 /**
76 * tb_available_credits() - Available credits for PCIe and DMA
77 * @port: Lane adapter to check
78 * @max_dp_streams: If non-%NULL stores maximum number of simultaneous DP
79 * streams possible through this lane adapter
80 */
tb_available_credits(const struct tb_port * port,size_t * max_dp_streams)81 static unsigned int tb_available_credits(const struct tb_port *port,
82 size_t *max_dp_streams)
83 {
84 const struct tb_switch *sw = port->sw;
85 int credits, usb3, pcie, spare;
86 size_t ndp;
87
88 usb3 = tb_acpi_may_tunnel_usb3() ? sw->max_usb3_credits : 0;
89 pcie = tb_acpi_may_tunnel_pcie() ? sw->max_pcie_credits : 0;
90
91 if (tb_acpi_is_xdomain_allowed()) {
92 spare = min_not_zero(sw->max_dma_credits, TB_DMA_CREDITS);
93 /* Add some credits for potential second DMA tunnel */
94 spare += TB_MIN_DMA_CREDITS;
95 } else {
96 spare = 0;
97 }
98
99 credits = tb_usable_credits(port);
100 if (tb_acpi_may_tunnel_dp()) {
101 /*
102 * Maximum number of DP streams possible through the
103 * lane adapter.
104 */
105 ndp = (credits - (usb3 + pcie + spare)) /
106 (sw->min_dp_aux_credits + sw->min_dp_main_credits);
107 } else {
108 ndp = 0;
109 }
110 credits -= ndp * (sw->min_dp_aux_credits + sw->min_dp_main_credits);
111 credits -= usb3;
112
113 if (max_dp_streams)
114 *max_dp_streams = ndp;
115
116 return credits > 0 ? credits : 0;
117 }
118
tb_tunnel_alloc(struct tb * tb,size_t npaths,enum tb_tunnel_type type)119 static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
120 enum tb_tunnel_type type)
121 {
122 struct tb_tunnel *tunnel;
123
124 tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
125 if (!tunnel)
126 return NULL;
127
128 tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
129 if (!tunnel->paths) {
130 tb_tunnel_free(tunnel);
131 return NULL;
132 }
133
134 INIT_LIST_HEAD(&tunnel->list);
135 tunnel->tb = tb;
136 tunnel->npaths = npaths;
137 tunnel->type = type;
138
139 return tunnel;
140 }
141
tb_pci_activate(struct tb_tunnel * tunnel,bool activate)142 static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
143 {
144 int res;
145
146 res = tb_pci_port_enable(tunnel->src_port, activate);
147 if (res)
148 return res;
149
150 if (tb_port_is_pcie_up(tunnel->dst_port))
151 return tb_pci_port_enable(tunnel->dst_port, activate);
152
153 return 0;
154 }
155
tb_pci_init_credits(struct tb_path_hop * hop)156 static int tb_pci_init_credits(struct tb_path_hop *hop)
157 {
158 struct tb_port *port = hop->in_port;
159 struct tb_switch *sw = port->sw;
160 unsigned int credits;
161
162 if (tb_port_use_credit_allocation(port)) {
163 unsigned int available;
164
165 available = tb_available_credits(port, NULL);
166 credits = min(sw->max_pcie_credits, available);
167
168 if (credits < TB_MIN_PCIE_CREDITS)
169 return -ENOSPC;
170
171 credits = max(TB_MIN_PCIE_CREDITS, credits);
172 } else {
173 if (tb_port_is_null(port))
174 credits = port->bonded ? 32 : 16;
175 else
176 credits = 7;
177 }
178
179 hop->initial_credits = credits;
180 return 0;
181 }
182
tb_pci_init_path(struct tb_path * path)183 static int tb_pci_init_path(struct tb_path *path)
184 {
185 struct tb_path_hop *hop;
186
187 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
188 path->egress_shared_buffer = TB_PATH_NONE;
189 path->ingress_fc_enable = TB_PATH_ALL;
190 path->ingress_shared_buffer = TB_PATH_NONE;
191 path->priority = 3;
192 path->weight = 1;
193 path->drop_packages = 0;
194
195 tb_path_for_each_hop(path, hop) {
196 int ret;
197
198 ret = tb_pci_init_credits(hop);
199 if (ret)
200 return ret;
201 }
202
203 return 0;
204 }
205
206 /**
207 * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
208 * @tb: Pointer to the domain structure
209 * @down: PCIe downstream adapter
210 * @alloc_hopid: Allocate HopIDs from visited ports
211 *
212 * If @down adapter is active, follows the tunnel to the PCIe upstream
213 * adapter and back. Returns the discovered tunnel or %NULL if there was
214 * no tunnel.
215 */
tb_tunnel_discover_pci(struct tb * tb,struct tb_port * down,bool alloc_hopid)216 struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down,
217 bool alloc_hopid)
218 {
219 struct tb_tunnel *tunnel;
220 struct tb_path *path;
221
222 if (!tb_pci_port_is_enabled(down))
223 return NULL;
224
225 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
226 if (!tunnel)
227 return NULL;
228
229 tunnel->activate = tb_pci_activate;
230 tunnel->src_port = down;
231
232 /*
233 * Discover both paths even if they are not complete. We will
234 * clean them up by calling tb_tunnel_deactivate() below in that
235 * case.
236 */
237 path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
238 &tunnel->dst_port, "PCIe Up", alloc_hopid);
239 if (!path) {
240 /* Just disable the downstream port */
241 tb_pci_port_enable(down, false);
242 goto err_free;
243 }
244 tunnel->paths[TB_PCI_PATH_UP] = path;
245 if (tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]))
246 goto err_free;
247
248 path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
249 "PCIe Down", alloc_hopid);
250 if (!path)
251 goto err_deactivate;
252 tunnel->paths[TB_PCI_PATH_DOWN] = path;
253 if (tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]))
254 goto err_deactivate;
255
256 /* Validate that the tunnel is complete */
257 if (!tb_port_is_pcie_up(tunnel->dst_port)) {
258 tb_port_warn(tunnel->dst_port,
259 "path does not end on a PCIe adapter, cleaning up\n");
260 goto err_deactivate;
261 }
262
263 if (down != tunnel->src_port) {
264 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
265 goto err_deactivate;
266 }
267
268 if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
269 tb_tunnel_warn(tunnel,
270 "tunnel is not fully activated, cleaning up\n");
271 goto err_deactivate;
272 }
273
274 tb_tunnel_dbg(tunnel, "discovered\n");
275 return tunnel;
276
277 err_deactivate:
278 tb_tunnel_deactivate(tunnel);
279 err_free:
280 tb_tunnel_free(tunnel);
281
282 return NULL;
283 }
284
285 /**
286 * tb_tunnel_alloc_pci() - allocate a pci tunnel
287 * @tb: Pointer to the domain structure
288 * @up: PCIe upstream adapter port
289 * @down: PCIe downstream adapter port
290 *
291 * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
292 * TB_TYPE_PCIE_DOWN.
293 *
294 * Return: Returns a tb_tunnel on success or NULL on failure.
295 */
tb_tunnel_alloc_pci(struct tb * tb,struct tb_port * up,struct tb_port * down)296 struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
297 struct tb_port *down)
298 {
299 struct tb_tunnel *tunnel;
300 struct tb_path *path;
301
302 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
303 if (!tunnel)
304 return NULL;
305
306 tunnel->activate = tb_pci_activate;
307 tunnel->src_port = down;
308 tunnel->dst_port = up;
309
310 path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
311 "PCIe Down");
312 if (!path)
313 goto err_free;
314 tunnel->paths[TB_PCI_PATH_DOWN] = path;
315 if (tb_pci_init_path(path))
316 goto err_free;
317
318 path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
319 "PCIe Up");
320 if (!path)
321 goto err_free;
322 tunnel->paths[TB_PCI_PATH_UP] = path;
323 if (tb_pci_init_path(path))
324 goto err_free;
325
326 return tunnel;
327
328 err_free:
329 tb_tunnel_free(tunnel);
330 return NULL;
331 }
332
tb_dp_is_usb4(const struct tb_switch * sw)333 static bool tb_dp_is_usb4(const struct tb_switch *sw)
334 {
335 /* Titan Ridge DP adapters need the same treatment as USB4 */
336 return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
337 }
338
tb_dp_cm_handshake(struct tb_port * in,struct tb_port * out)339 static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
340 {
341 int timeout = 10;
342 u32 val;
343 int ret;
344
345 /* Both ends need to support this */
346 if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
347 return 0;
348
349 ret = tb_port_read(out, &val, TB_CFG_PORT,
350 out->cap_adap + DP_STATUS_CTRL, 1);
351 if (ret)
352 return ret;
353
354 val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;
355
356 ret = tb_port_write(out, &val, TB_CFG_PORT,
357 out->cap_adap + DP_STATUS_CTRL, 1);
358 if (ret)
359 return ret;
360
361 do {
362 ret = tb_port_read(out, &val, TB_CFG_PORT,
363 out->cap_adap + DP_STATUS_CTRL, 1);
364 if (ret)
365 return ret;
366 if (!(val & DP_STATUS_CTRL_CMHS))
367 return 0;
368 usleep_range(10, 100);
369 } while (timeout--);
370
371 return -ETIMEDOUT;
372 }
373
tb_dp_cap_get_rate(u32 val)374 static inline u32 tb_dp_cap_get_rate(u32 val)
375 {
376 u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;
377
378 switch (rate) {
379 case DP_COMMON_CAP_RATE_RBR:
380 return 1620;
381 case DP_COMMON_CAP_RATE_HBR:
382 return 2700;
383 case DP_COMMON_CAP_RATE_HBR2:
384 return 5400;
385 case DP_COMMON_CAP_RATE_HBR3:
386 return 8100;
387 default:
388 return 0;
389 }
390 }
391
tb_dp_cap_set_rate(u32 val,u32 rate)392 static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
393 {
394 val &= ~DP_COMMON_CAP_RATE_MASK;
395 switch (rate) {
396 default:
397 WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
398 fallthrough;
399 case 1620:
400 val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
401 break;
402 case 2700:
403 val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
404 break;
405 case 5400:
406 val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
407 break;
408 case 8100:
409 val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
410 break;
411 }
412 return val;
413 }
414
tb_dp_cap_get_lanes(u32 val)415 static inline u32 tb_dp_cap_get_lanes(u32 val)
416 {
417 u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;
418
419 switch (lanes) {
420 case DP_COMMON_CAP_1_LANE:
421 return 1;
422 case DP_COMMON_CAP_2_LANES:
423 return 2;
424 case DP_COMMON_CAP_4_LANES:
425 return 4;
426 default:
427 return 0;
428 }
429 }
430
tb_dp_cap_set_lanes(u32 val,u32 lanes)431 static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
432 {
433 val &= ~DP_COMMON_CAP_LANES_MASK;
434 switch (lanes) {
435 default:
436 WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
437 lanes);
438 fallthrough;
439 case 1:
440 val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
441 break;
442 case 2:
443 val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
444 break;
445 case 4:
446 val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
447 break;
448 }
449 return val;
450 }
451
tb_dp_bandwidth(unsigned int rate,unsigned int lanes)452 static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
453 {
454 /* Tunneling removes the DP 8b/10b encoding */
455 return rate * lanes * 8 / 10;
456 }
457
tb_dp_reduce_bandwidth(int max_bw,u32 in_rate,u32 in_lanes,u32 out_rate,u32 out_lanes,u32 * new_rate,u32 * new_lanes)458 static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes,
459 u32 out_rate, u32 out_lanes, u32 *new_rate,
460 u32 *new_lanes)
461 {
462 static const u32 dp_bw[][2] = {
463 /* Mb/s, lanes */
464 { 8100, 4 }, /* 25920 Mb/s */
465 { 5400, 4 }, /* 17280 Mb/s */
466 { 8100, 2 }, /* 12960 Mb/s */
467 { 2700, 4 }, /* 8640 Mb/s */
468 { 5400, 2 }, /* 8640 Mb/s */
469 { 8100, 1 }, /* 6480 Mb/s */
470 { 1620, 4 }, /* 5184 Mb/s */
471 { 5400, 1 }, /* 4320 Mb/s */
472 { 2700, 2 }, /* 4320 Mb/s */
473 { 1620, 2 }, /* 2592 Mb/s */
474 { 2700, 1 }, /* 2160 Mb/s */
475 { 1620, 1 }, /* 1296 Mb/s */
476 };
477 unsigned int i;
478
479 /*
480 * Find a combination that can fit into max_bw and does not
481 * exceed the maximum rate and lanes supported by the DP OUT and
482 * DP IN adapters.
483 */
484 for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
485 if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
486 continue;
487
488 if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
489 continue;
490
491 if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
492 *new_rate = dp_bw[i][0];
493 *new_lanes = dp_bw[i][1];
494 return 0;
495 }
496 }
497
498 return -ENOSR;
499 }
500
tb_dp_xchg_caps(struct tb_tunnel * tunnel)501 static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
502 {
503 u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
504 struct tb_port *out = tunnel->dst_port;
505 struct tb_port *in = tunnel->src_port;
506 int ret, max_bw;
507
508 /*
509 * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
510 * newer generation hardware.
511 */
512 if (in->sw->generation < 2 || out->sw->generation < 2)
513 return 0;
514
515 /*
516 * Perform connection manager handshake between IN and OUT ports
517 * before capabilities exchange can take place.
518 */
519 ret = tb_dp_cm_handshake(in, out);
520 if (ret)
521 return ret;
522
523 /* Read both DP_LOCAL_CAP registers */
524 ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
525 in->cap_adap + DP_LOCAL_CAP, 1);
526 if (ret)
527 return ret;
528
529 ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
530 out->cap_adap + DP_LOCAL_CAP, 1);
531 if (ret)
532 return ret;
533
534 /* Write IN local caps to OUT remote caps */
535 ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
536 out->cap_adap + DP_REMOTE_CAP, 1);
537 if (ret)
538 return ret;
539
540 in_rate = tb_dp_cap_get_rate(in_dp_cap);
541 in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
542 tb_port_dbg(in, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
543 in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));
544
545 /*
546 * If the tunnel bandwidth is limited (max_bw is set) then see
547 * if we need to reduce bandwidth to fit there.
548 */
549 out_rate = tb_dp_cap_get_rate(out_dp_cap);
550 out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
551 bw = tb_dp_bandwidth(out_rate, out_lanes);
552 tb_port_dbg(out, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
553 out_rate, out_lanes, bw);
554
555 if (in->sw->config.depth < out->sw->config.depth)
556 max_bw = tunnel->max_down;
557 else
558 max_bw = tunnel->max_up;
559
560 if (max_bw && bw > max_bw) {
561 u32 new_rate, new_lanes, new_bw;
562
563 ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes,
564 out_rate, out_lanes, &new_rate,
565 &new_lanes);
566 if (ret) {
567 tb_port_info(out, "not enough bandwidth for DP tunnel\n");
568 return ret;
569 }
570
571 new_bw = tb_dp_bandwidth(new_rate, new_lanes);
572 tb_port_dbg(out, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
573 new_rate, new_lanes, new_bw);
574
575 /*
576 * Set new rate and number of lanes before writing it to
577 * the IN port remote caps.
578 */
579 out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
580 out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
581 }
582
583 return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
584 in->cap_adap + DP_REMOTE_CAP, 1);
585 }
586
tb_dp_activate(struct tb_tunnel * tunnel,bool active)587 static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
588 {
589 int ret;
590
591 if (active) {
592 struct tb_path **paths;
593 int last;
594
595 paths = tunnel->paths;
596 last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
597
598 tb_dp_port_set_hops(tunnel->src_port,
599 paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
600 paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
601 paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
602
603 tb_dp_port_set_hops(tunnel->dst_port,
604 paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
605 paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
606 paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
607 } else {
608 tb_dp_port_hpd_clear(tunnel->src_port);
609 tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
610 if (tb_port_is_dpout(tunnel->dst_port))
611 tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
612 }
613
614 ret = tb_dp_port_enable(tunnel->src_port, active);
615 if (ret)
616 return ret;
617
618 if (tb_port_is_dpout(tunnel->dst_port))
619 return tb_dp_port_enable(tunnel->dst_port, active);
620
621 return 0;
622 }
623
tb_dp_consumed_bandwidth(struct tb_tunnel * tunnel,int * consumed_up,int * consumed_down)624 static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
625 int *consumed_down)
626 {
627 struct tb_port *in = tunnel->src_port;
628 const struct tb_switch *sw = in->sw;
629 u32 val, rate = 0, lanes = 0;
630 int ret;
631
632 if (tb_dp_is_usb4(sw)) {
633 int timeout = 20;
634
635 /*
636 * Wait for DPRX done. Normally it should be already set
637 * for active tunnel.
638 */
639 do {
640 ret = tb_port_read(in, &val, TB_CFG_PORT,
641 in->cap_adap + DP_COMMON_CAP, 1);
642 if (ret)
643 return ret;
644
645 if (val & DP_COMMON_CAP_DPRX_DONE) {
646 rate = tb_dp_cap_get_rate(val);
647 lanes = tb_dp_cap_get_lanes(val);
648 break;
649 }
650 msleep(250);
651 } while (timeout--);
652
653 if (!timeout)
654 return -ETIMEDOUT;
655 } else if (sw->generation >= 2) {
656 /*
657 * Read from the copied remote cap so that we take into
658 * account if capabilities were reduced during exchange.
659 */
660 ret = tb_port_read(in, &val, TB_CFG_PORT,
661 in->cap_adap + DP_REMOTE_CAP, 1);
662 if (ret)
663 return ret;
664
665 rate = tb_dp_cap_get_rate(val);
666 lanes = tb_dp_cap_get_lanes(val);
667 } else {
668 /* No bandwidth management for legacy devices */
669 *consumed_up = 0;
670 *consumed_down = 0;
671 return 0;
672 }
673
674 if (in->sw->config.depth < tunnel->dst_port->sw->config.depth) {
675 *consumed_up = 0;
676 *consumed_down = tb_dp_bandwidth(rate, lanes);
677 } else {
678 *consumed_up = tb_dp_bandwidth(rate, lanes);
679 *consumed_down = 0;
680 }
681
682 return 0;
683 }
684
tb_dp_init_aux_credits(struct tb_path_hop * hop)685 static void tb_dp_init_aux_credits(struct tb_path_hop *hop)
686 {
687 struct tb_port *port = hop->in_port;
688 struct tb_switch *sw = port->sw;
689
690 if (tb_port_use_credit_allocation(port))
691 hop->initial_credits = sw->min_dp_aux_credits;
692 else
693 hop->initial_credits = 1;
694 }
695
tb_dp_init_aux_path(struct tb_path * path)696 static void tb_dp_init_aux_path(struct tb_path *path)
697 {
698 struct tb_path_hop *hop;
699
700 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
701 path->egress_shared_buffer = TB_PATH_NONE;
702 path->ingress_fc_enable = TB_PATH_ALL;
703 path->ingress_shared_buffer = TB_PATH_NONE;
704 path->priority = 2;
705 path->weight = 1;
706
707 tb_path_for_each_hop(path, hop)
708 tb_dp_init_aux_credits(hop);
709 }
710
tb_dp_init_video_credits(struct tb_path_hop * hop)711 static int tb_dp_init_video_credits(struct tb_path_hop *hop)
712 {
713 struct tb_port *port = hop->in_port;
714 struct tb_switch *sw = port->sw;
715
716 if (tb_port_use_credit_allocation(port)) {
717 unsigned int nfc_credits;
718 size_t max_dp_streams;
719
720 tb_available_credits(port, &max_dp_streams);
721 /*
722 * Read the number of currently allocated NFC credits
723 * from the lane adapter. Since we only use them for DP
724 * tunneling we can use that to figure out how many DP
725 * tunnels already go through the lane adapter.
726 */
727 nfc_credits = port->config.nfc_credits &
728 ADP_CS_4_NFC_BUFFERS_MASK;
729 if (nfc_credits / sw->min_dp_main_credits > max_dp_streams)
730 return -ENOSPC;
731
732 hop->nfc_credits = sw->min_dp_main_credits;
733 } else {
734 hop->nfc_credits = min(port->total_credits - 2, 12U);
735 }
736
737 return 0;
738 }
739
tb_dp_init_video_path(struct tb_path * path)740 static int tb_dp_init_video_path(struct tb_path *path)
741 {
742 struct tb_path_hop *hop;
743
744 path->egress_fc_enable = TB_PATH_NONE;
745 path->egress_shared_buffer = TB_PATH_NONE;
746 path->ingress_fc_enable = TB_PATH_NONE;
747 path->ingress_shared_buffer = TB_PATH_NONE;
748 path->priority = 1;
749 path->weight = 1;
750
751 tb_path_for_each_hop(path, hop) {
752 int ret;
753
754 ret = tb_dp_init_video_credits(hop);
755 if (ret)
756 return ret;
757 }
758
759 return 0;
760 }
761
762 /**
763 * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
764 * @tb: Pointer to the domain structure
765 * @in: DP in adapter
766 * @alloc_hopid: Allocate HopIDs from visited ports
767 *
768 * If @in adapter is active, follows the tunnel to the DP out adapter
769 * and back. Returns the discovered tunnel or %NULL if there was no
770 * tunnel.
771 *
772 * Return: DP tunnel or %NULL if no tunnel found.
773 */
tb_tunnel_discover_dp(struct tb * tb,struct tb_port * in,bool alloc_hopid)774 struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in,
775 bool alloc_hopid)
776 {
777 struct tb_tunnel *tunnel;
778 struct tb_port *port;
779 struct tb_path *path;
780
781 if (!tb_dp_port_is_enabled(in))
782 return NULL;
783
784 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
785 if (!tunnel)
786 return NULL;
787
788 tunnel->init = tb_dp_xchg_caps;
789 tunnel->activate = tb_dp_activate;
790 tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
791 tunnel->src_port = in;
792
793 path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
794 &tunnel->dst_port, "Video", alloc_hopid);
795 if (!path) {
796 /* Just disable the DP IN port */
797 tb_dp_port_enable(in, false);
798 goto err_free;
799 }
800 tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
801 if (tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT]))
802 goto err_free;
803
804 path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX",
805 alloc_hopid);
806 if (!path)
807 goto err_deactivate;
808 tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
809 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
810
811 path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
812 &port, "AUX RX", alloc_hopid);
813 if (!path)
814 goto err_deactivate;
815 tunnel->paths[TB_DP_AUX_PATH_IN] = path;
816 tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);
817
818 /* Validate that the tunnel is complete */
819 if (!tb_port_is_dpout(tunnel->dst_port)) {
820 tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
821 goto err_deactivate;
822 }
823
824 if (!tb_dp_port_is_enabled(tunnel->dst_port))
825 goto err_deactivate;
826
827 if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
828 goto err_deactivate;
829
830 if (port != tunnel->src_port) {
831 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
832 goto err_deactivate;
833 }
834
835 tb_tunnel_dbg(tunnel, "discovered\n");
836 return tunnel;
837
838 err_deactivate:
839 tb_tunnel_deactivate(tunnel);
840 err_free:
841 tb_tunnel_free(tunnel);
842
843 return NULL;
844 }
845
846 /**
847 * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
848 * @tb: Pointer to the domain structure
849 * @in: DP in adapter port
850 * @out: DP out adapter port
851 * @link_nr: Preferred lane adapter when the link is not bonded
852 * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0
853 * if not limited)
854 * @max_down: Maximum available downstream bandwidth for the DP tunnel
855 * (%0 if not limited)
856 *
857 * Allocates a tunnel between @in and @out that is capable of tunneling
858 * Display Port traffic.
859 *
860 * Return: Returns a tb_tunnel on success or NULL on failure.
861 */
tb_tunnel_alloc_dp(struct tb * tb,struct tb_port * in,struct tb_port * out,int link_nr,int max_up,int max_down)862 struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
863 struct tb_port *out, int link_nr,
864 int max_up, int max_down)
865 {
866 struct tb_tunnel *tunnel;
867 struct tb_path **paths;
868 struct tb_path *path;
869
870 if (WARN_ON(!in->cap_adap || !out->cap_adap))
871 return NULL;
872
873 tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
874 if (!tunnel)
875 return NULL;
876
877 tunnel->init = tb_dp_xchg_caps;
878 tunnel->activate = tb_dp_activate;
879 tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
880 tunnel->src_port = in;
881 tunnel->dst_port = out;
882 tunnel->max_up = max_up;
883 tunnel->max_down = max_down;
884
885 paths = tunnel->paths;
886
887 path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
888 link_nr, "Video");
889 if (!path)
890 goto err_free;
891 tb_dp_init_video_path(path);
892 paths[TB_DP_VIDEO_PATH_OUT] = path;
893
894 path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
895 TB_DP_AUX_TX_HOPID, link_nr, "AUX TX");
896 if (!path)
897 goto err_free;
898 tb_dp_init_aux_path(path);
899 paths[TB_DP_AUX_PATH_OUT] = path;
900
901 path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
902 TB_DP_AUX_RX_HOPID, link_nr, "AUX RX");
903 if (!path)
904 goto err_free;
905 tb_dp_init_aux_path(path);
906 paths[TB_DP_AUX_PATH_IN] = path;
907
908 return tunnel;
909
910 err_free:
911 tb_tunnel_free(tunnel);
912 return NULL;
913 }
914
tb_dma_available_credits(const struct tb_port * port)915 static unsigned int tb_dma_available_credits(const struct tb_port *port)
916 {
917 const struct tb_switch *sw = port->sw;
918 int credits;
919
920 credits = tb_available_credits(port, NULL);
921 if (tb_acpi_may_tunnel_pcie())
922 credits -= sw->max_pcie_credits;
923 credits -= port->dma_credits;
924
925 return credits > 0 ? credits : 0;
926 }
927
tb_dma_reserve_credits(struct tb_path_hop * hop,unsigned int credits)928 static int tb_dma_reserve_credits(struct tb_path_hop *hop, unsigned int credits)
929 {
930 struct tb_port *port = hop->in_port;
931
932 if (tb_port_use_credit_allocation(port)) {
933 unsigned int available = tb_dma_available_credits(port);
934
935 /*
936 * Need to have at least TB_MIN_DMA_CREDITS, otherwise
937 * DMA path cannot be established.
938 */
939 if (available < TB_MIN_DMA_CREDITS)
940 return -ENOSPC;
941
942 while (credits > available)
943 credits--;
944
945 tb_port_dbg(port, "reserving %u credits for DMA path\n",
946 credits);
947
948 port->dma_credits += credits;
949 } else {
950 if (tb_port_is_null(port))
951 credits = port->bonded ? 14 : 6;
952 else
953 credits = min(port->total_credits, credits);
954 }
955
956 hop->initial_credits = credits;
957 return 0;
958 }
959
960 /* Path from lane adapter to NHI */
tb_dma_init_rx_path(struct tb_path * path,unsigned int credits)961 static int tb_dma_init_rx_path(struct tb_path *path, unsigned int credits)
962 {
963 struct tb_path_hop *hop;
964 unsigned int i, tmp;
965
966 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
967 path->ingress_fc_enable = TB_PATH_ALL;
968 path->egress_shared_buffer = TB_PATH_NONE;
969 path->ingress_shared_buffer = TB_PATH_NONE;
970 path->priority = 5;
971 path->weight = 1;
972 path->clear_fc = true;
973
974 /*
975 * First lane adapter is the one connected to the remote host.
976 * We don't tunnel other traffic over this link so can use all
977 * the credits (except the ones reserved for control traffic).
978 */
979 hop = &path->hops[0];
980 tmp = min(tb_usable_credits(hop->in_port), credits);
981 hop->initial_credits = tmp;
982 hop->in_port->dma_credits += tmp;
983
984 for (i = 1; i < path->path_length; i++) {
985 int ret;
986
987 ret = tb_dma_reserve_credits(&path->hops[i], credits);
988 if (ret)
989 return ret;
990 }
991
992 return 0;
993 }
994
995 /* Path from NHI to lane adapter */
tb_dma_init_tx_path(struct tb_path * path,unsigned int credits)996 static int tb_dma_init_tx_path(struct tb_path *path, unsigned int credits)
997 {
998 struct tb_path_hop *hop;
999
1000 path->egress_fc_enable = TB_PATH_ALL;
1001 path->ingress_fc_enable = TB_PATH_ALL;
1002 path->egress_shared_buffer = TB_PATH_NONE;
1003 path->ingress_shared_buffer = TB_PATH_NONE;
1004 path->priority = 5;
1005 path->weight = 1;
1006 path->clear_fc = true;
1007
1008 tb_path_for_each_hop(path, hop) {
1009 int ret;
1010
1011 ret = tb_dma_reserve_credits(hop, credits);
1012 if (ret)
1013 return ret;
1014 }
1015
1016 return 0;
1017 }
1018
tb_dma_release_credits(struct tb_path_hop * hop)1019 static void tb_dma_release_credits(struct tb_path_hop *hop)
1020 {
1021 struct tb_port *port = hop->in_port;
1022
1023 if (tb_port_use_credit_allocation(port)) {
1024 port->dma_credits -= hop->initial_credits;
1025
1026 tb_port_dbg(port, "released %u DMA path credits\n",
1027 hop->initial_credits);
1028 }
1029 }
1030
tb_dma_deinit_path(struct tb_path * path)1031 static void tb_dma_deinit_path(struct tb_path *path)
1032 {
1033 struct tb_path_hop *hop;
1034
1035 tb_path_for_each_hop(path, hop)
1036 tb_dma_release_credits(hop);
1037 }
1038
tb_dma_deinit(struct tb_tunnel * tunnel)1039 static void tb_dma_deinit(struct tb_tunnel *tunnel)
1040 {
1041 int i;
1042
1043 for (i = 0; i < tunnel->npaths; i++) {
1044 if (!tunnel->paths[i])
1045 continue;
1046 tb_dma_deinit_path(tunnel->paths[i]);
1047 }
1048 }
1049
1050 /**
1051 * tb_tunnel_alloc_dma() - allocate a DMA tunnel
1052 * @tb: Pointer to the domain structure
1053 * @nhi: Host controller port
1054 * @dst: Destination null port which the other domain is connected to
1055 * @transmit_path: HopID used for transmitting packets
1056 * @transmit_ring: NHI ring number used to send packets towards the
1057 * other domain. Set to %-1 if TX path is not needed.
1058 * @receive_path: HopID used for receiving packets
1059 * @receive_ring: NHI ring number used to receive packets from the
1060 * other domain. Set to %-1 if RX path is not needed.
1061 *
1062 * Return: Returns a tb_tunnel on success or NULL on failure.
1063 */
tb_tunnel_alloc_dma(struct tb * tb,struct tb_port * nhi,struct tb_port * dst,int transmit_path,int transmit_ring,int receive_path,int receive_ring)1064 struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
1065 struct tb_port *dst, int transmit_path,
1066 int transmit_ring, int receive_path,
1067 int receive_ring)
1068 {
1069 struct tb_tunnel *tunnel;
1070 size_t npaths = 0, i = 0;
1071 struct tb_path *path;
1072 int credits;
1073
1074 if (receive_ring > 0)
1075 npaths++;
1076 if (transmit_ring > 0)
1077 npaths++;
1078
1079 if (WARN_ON(!npaths))
1080 return NULL;
1081
1082 tunnel = tb_tunnel_alloc(tb, npaths, TB_TUNNEL_DMA);
1083 if (!tunnel)
1084 return NULL;
1085
1086 tunnel->src_port = nhi;
1087 tunnel->dst_port = dst;
1088 tunnel->deinit = tb_dma_deinit;
1089
1090 credits = min_not_zero(TB_DMA_CREDITS, nhi->sw->max_dma_credits);
1091
1092 if (receive_ring > 0) {
1093 path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0,
1094 "DMA RX");
1095 if (!path)
1096 goto err_free;
1097 tunnel->paths[i++] = path;
1098 if (tb_dma_init_rx_path(path, credits)) {
1099 tb_tunnel_dbg(tunnel, "not enough buffers for RX path\n");
1100 goto err_free;
1101 }
1102 }
1103
1104 if (transmit_ring > 0) {
1105 path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0,
1106 "DMA TX");
1107 if (!path)
1108 goto err_free;
1109 tunnel->paths[i++] = path;
1110 if (tb_dma_init_tx_path(path, credits)) {
1111 tb_tunnel_dbg(tunnel, "not enough buffers for TX path\n");
1112 goto err_free;
1113 }
1114 }
1115
1116 return tunnel;
1117
1118 err_free:
1119 tb_tunnel_free(tunnel);
1120 return NULL;
1121 }
1122
1123 /**
1124 * tb_tunnel_match_dma() - Match DMA tunnel
1125 * @tunnel: Tunnel to match
1126 * @transmit_path: HopID used for transmitting packets. Pass %-1 to ignore.
1127 * @transmit_ring: NHI ring number used to send packets towards the
1128 * other domain. Pass %-1 to ignore.
1129 * @receive_path: HopID used for receiving packets. Pass %-1 to ignore.
1130 * @receive_ring: NHI ring number used to receive packets from the
1131 * other domain. Pass %-1 to ignore.
1132 *
1133 * This function can be used to match specific DMA tunnel, if there are
1134 * multiple DMA tunnels going through the same XDomain connection.
1135 * Returns true if there is match and false otherwise.
1136 */
tb_tunnel_match_dma(const struct tb_tunnel * tunnel,int transmit_path,int transmit_ring,int receive_path,int receive_ring)1137 bool tb_tunnel_match_dma(const struct tb_tunnel *tunnel, int transmit_path,
1138 int transmit_ring, int receive_path, int receive_ring)
1139 {
1140 const struct tb_path *tx_path = NULL, *rx_path = NULL;
1141 int i;
1142
1143 if (!receive_ring || !transmit_ring)
1144 return false;
1145
1146 for (i = 0; i < tunnel->npaths; i++) {
1147 const struct tb_path *path = tunnel->paths[i];
1148
1149 if (!path)
1150 continue;
1151
1152 if (tb_port_is_nhi(path->hops[0].in_port))
1153 tx_path = path;
1154 else if (tb_port_is_nhi(path->hops[path->path_length - 1].out_port))
1155 rx_path = path;
1156 }
1157
1158 if (transmit_ring > 0 || transmit_path > 0) {
1159 if (!tx_path)
1160 return false;
1161 if (transmit_ring > 0 &&
1162 (tx_path->hops[0].in_hop_index != transmit_ring))
1163 return false;
1164 if (transmit_path > 0 &&
1165 (tx_path->hops[tx_path->path_length - 1].next_hop_index != transmit_path))
1166 return false;
1167 }
1168
1169 if (receive_ring > 0 || receive_path > 0) {
1170 if (!rx_path)
1171 return false;
1172 if (receive_path > 0 &&
1173 (rx_path->hops[0].in_hop_index != receive_path))
1174 return false;
1175 if (receive_ring > 0 &&
1176 (rx_path->hops[rx_path->path_length - 1].next_hop_index != receive_ring))
1177 return false;
1178 }
1179
1180 return true;
1181 }
1182
tb_usb3_max_link_rate(struct tb_port * up,struct tb_port * down)1183 static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down)
1184 {
1185 int ret, up_max_rate, down_max_rate;
1186
1187 ret = usb4_usb3_port_max_link_rate(up);
1188 if (ret < 0)
1189 return ret;
1190 up_max_rate = ret;
1191
1192 ret = usb4_usb3_port_max_link_rate(down);
1193 if (ret < 0)
1194 return ret;
1195 down_max_rate = ret;
1196
1197 return min(up_max_rate, down_max_rate);
1198 }
1199
tb_usb3_init(struct tb_tunnel * tunnel)1200 static int tb_usb3_init(struct tb_tunnel *tunnel)
1201 {
1202 tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n",
1203 tunnel->allocated_up, tunnel->allocated_down);
1204
1205 return usb4_usb3_port_allocate_bandwidth(tunnel->src_port,
1206 &tunnel->allocated_up,
1207 &tunnel->allocated_down);
1208 }
1209
tb_usb3_activate(struct tb_tunnel * tunnel,bool activate)1210 static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate)
1211 {
1212 int res;
1213
1214 res = tb_usb3_port_enable(tunnel->src_port, activate);
1215 if (res)
1216 return res;
1217
1218 if (tb_port_is_usb3_up(tunnel->dst_port))
1219 return tb_usb3_port_enable(tunnel->dst_port, activate);
1220
1221 return 0;
1222 }
1223
tb_usb3_consumed_bandwidth(struct tb_tunnel * tunnel,int * consumed_up,int * consumed_down)1224 static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel,
1225 int *consumed_up, int *consumed_down)
1226 {
1227 int pcie_enabled = tb_acpi_may_tunnel_pcie();
1228
1229 /*
1230 * PCIe tunneling, if enabled, affects the USB3 bandwidth so
1231 * take that it into account here.
1232 */
1233 *consumed_up = tunnel->allocated_up * (3 + pcie_enabled) / 3;
1234 *consumed_down = tunnel->allocated_down * (3 + pcie_enabled) / 3;
1235 return 0;
1236 }
1237
tb_usb3_release_unused_bandwidth(struct tb_tunnel * tunnel)1238 static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel)
1239 {
1240 int ret;
1241
1242 ret = usb4_usb3_port_release_bandwidth(tunnel->src_port,
1243 &tunnel->allocated_up,
1244 &tunnel->allocated_down);
1245 if (ret)
1246 return ret;
1247
1248 tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n",
1249 tunnel->allocated_up, tunnel->allocated_down);
1250 return 0;
1251 }
1252
tb_usb3_reclaim_available_bandwidth(struct tb_tunnel * tunnel,int * available_up,int * available_down)1253 static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
1254 int *available_up,
1255 int *available_down)
1256 {
1257 int ret, max_rate, allocate_up, allocate_down;
1258
1259 ret = usb4_usb3_port_actual_link_rate(tunnel->src_port);
1260 if (ret < 0) {
1261 tb_tunnel_warn(tunnel, "failed to read actual link rate\n");
1262 return;
1263 } else if (!ret) {
1264 /* Use maximum link rate if the link valid is not set */
1265 ret = tb_usb3_max_link_rate(tunnel->dst_port, tunnel->src_port);
1266 if (ret < 0) {
1267 tb_tunnel_warn(tunnel, "failed to read maximum link rate\n");
1268 return;
1269 }
1270 }
1271
1272 /*
1273 * 90% of the max rate can be allocated for isochronous
1274 * transfers.
1275 */
1276 max_rate = ret * 90 / 100;
1277
1278 /* No need to reclaim if already at maximum */
1279 if (tunnel->allocated_up >= max_rate &&
1280 tunnel->allocated_down >= max_rate)
1281 return;
1282
1283 /* Don't go lower than what is already allocated */
1284 allocate_up = min(max_rate, *available_up);
1285 if (allocate_up < tunnel->allocated_up)
1286 allocate_up = tunnel->allocated_up;
1287
1288 allocate_down = min(max_rate, *available_down);
1289 if (allocate_down < tunnel->allocated_down)
1290 allocate_down = tunnel->allocated_down;
1291
1292 /* If no changes no need to do more */
1293 if (allocate_up == tunnel->allocated_up &&
1294 allocate_down == tunnel->allocated_down)
1295 return;
1296
1297 ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up,
1298 &allocate_down);
1299 if (ret) {
1300 tb_tunnel_info(tunnel, "failed to allocate bandwidth\n");
1301 return;
1302 }
1303
1304 tunnel->allocated_up = allocate_up;
1305 *available_up -= tunnel->allocated_up;
1306
1307 tunnel->allocated_down = allocate_down;
1308 *available_down -= tunnel->allocated_down;
1309
1310 tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n",
1311 tunnel->allocated_up, tunnel->allocated_down);
1312 }
1313
tb_usb3_init_credits(struct tb_path_hop * hop)1314 static void tb_usb3_init_credits(struct tb_path_hop *hop)
1315 {
1316 struct tb_port *port = hop->in_port;
1317 struct tb_switch *sw = port->sw;
1318 unsigned int credits;
1319
1320 if (tb_port_use_credit_allocation(port)) {
1321 credits = sw->max_usb3_credits;
1322 } else {
1323 if (tb_port_is_null(port))
1324 credits = port->bonded ? 32 : 16;
1325 else
1326 credits = 7;
1327 }
1328
1329 hop->initial_credits = credits;
1330 }
1331
tb_usb3_init_path(struct tb_path * path)1332 static void tb_usb3_init_path(struct tb_path *path)
1333 {
1334 struct tb_path_hop *hop;
1335
1336 path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1337 path->egress_shared_buffer = TB_PATH_NONE;
1338 path->ingress_fc_enable = TB_PATH_ALL;
1339 path->ingress_shared_buffer = TB_PATH_NONE;
1340 path->priority = 3;
1341 path->weight = 3;
1342 path->drop_packages = 0;
1343
1344 tb_path_for_each_hop(path, hop)
1345 tb_usb3_init_credits(hop);
1346 }
1347
1348 /**
1349 * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
1350 * @tb: Pointer to the domain structure
1351 * @down: USB3 downstream adapter
1352 * @alloc_hopid: Allocate HopIDs from visited ports
1353 *
1354 * If @down adapter is active, follows the tunnel to the USB3 upstream
1355 * adapter and back. Returns the discovered tunnel or %NULL if there was
1356 * no tunnel.
1357 */
tb_tunnel_discover_usb3(struct tb * tb,struct tb_port * down,bool alloc_hopid)1358 struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down,
1359 bool alloc_hopid)
1360 {
1361 struct tb_tunnel *tunnel;
1362 struct tb_path *path;
1363
1364 if (!tb_usb3_port_is_enabled(down))
1365 return NULL;
1366
1367 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1368 if (!tunnel)
1369 return NULL;
1370
1371 tunnel->activate = tb_usb3_activate;
1372 tunnel->src_port = down;
1373
1374 /*
1375 * Discover both paths even if they are not complete. We will
1376 * clean them up by calling tb_tunnel_deactivate() below in that
1377 * case.
1378 */
1379 path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
1380 &tunnel->dst_port, "USB3 Down", alloc_hopid);
1381 if (!path) {
1382 /* Just disable the downstream port */
1383 tb_usb3_port_enable(down, false);
1384 goto err_free;
1385 }
1386 tunnel->paths[TB_USB3_PATH_DOWN] = path;
1387 tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
1388
1389 path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
1390 "USB3 Up", alloc_hopid);
1391 if (!path)
1392 goto err_deactivate;
1393 tunnel->paths[TB_USB3_PATH_UP] = path;
1394 tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]);
1395
1396 /* Validate that the tunnel is complete */
1397 if (!tb_port_is_usb3_up(tunnel->dst_port)) {
1398 tb_port_warn(tunnel->dst_port,
1399 "path does not end on an USB3 adapter, cleaning up\n");
1400 goto err_deactivate;
1401 }
1402
1403 if (down != tunnel->src_port) {
1404 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
1405 goto err_deactivate;
1406 }
1407
1408 if (!tb_usb3_port_is_enabled(tunnel->dst_port)) {
1409 tb_tunnel_warn(tunnel,
1410 "tunnel is not fully activated, cleaning up\n");
1411 goto err_deactivate;
1412 }
1413
1414 if (!tb_route(down->sw)) {
1415 int ret;
1416
1417 /*
1418 * Read the initial bandwidth allocation for the first
1419 * hop tunnel.
1420 */
1421 ret = usb4_usb3_port_allocated_bandwidth(down,
1422 &tunnel->allocated_up, &tunnel->allocated_down);
1423 if (ret)
1424 goto err_deactivate;
1425
1426 tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n",
1427 tunnel->allocated_up, tunnel->allocated_down);
1428
1429 tunnel->init = tb_usb3_init;
1430 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1431 tunnel->release_unused_bandwidth =
1432 tb_usb3_release_unused_bandwidth;
1433 tunnel->reclaim_available_bandwidth =
1434 tb_usb3_reclaim_available_bandwidth;
1435 }
1436
1437 tb_tunnel_dbg(tunnel, "discovered\n");
1438 return tunnel;
1439
1440 err_deactivate:
1441 tb_tunnel_deactivate(tunnel);
1442 err_free:
1443 tb_tunnel_free(tunnel);
1444
1445 return NULL;
1446 }
1447
1448 /**
1449 * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel
1450 * @tb: Pointer to the domain structure
1451 * @up: USB3 upstream adapter port
1452 * @down: USB3 downstream adapter port
1453 * @max_up: Maximum available upstream bandwidth for the USB3 tunnel (%0
1454 * if not limited).
1455 * @max_down: Maximum available downstream bandwidth for the USB3 tunnel
1456 * (%0 if not limited).
1457 *
1458 * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and
1459 * @TB_TYPE_USB3_DOWN.
1460 *
1461 * Return: Returns a tb_tunnel on success or %NULL on failure.
1462 */
tb_tunnel_alloc_usb3(struct tb * tb,struct tb_port * up,struct tb_port * down,int max_up,int max_down)1463 struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
1464 struct tb_port *down, int max_up,
1465 int max_down)
1466 {
1467 struct tb_tunnel *tunnel;
1468 struct tb_path *path;
1469 int max_rate = 0;
1470
1471 /*
1472 * Check that we have enough bandwidth available for the new
1473 * USB3 tunnel.
1474 */
1475 if (max_up > 0 || max_down > 0) {
1476 max_rate = tb_usb3_max_link_rate(down, up);
1477 if (max_rate < 0)
1478 return NULL;
1479
1480 /* Only 90% can be allocated for USB3 isochronous transfers */
1481 max_rate = max_rate * 90 / 100;
1482 tb_port_dbg(up, "required bandwidth for USB3 tunnel %d Mb/s\n",
1483 max_rate);
1484
1485 if (max_rate > max_up || max_rate > max_down) {
1486 tb_port_warn(up, "not enough bandwidth for USB3 tunnel\n");
1487 return NULL;
1488 }
1489 }
1490
1491 tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1492 if (!tunnel)
1493 return NULL;
1494
1495 tunnel->activate = tb_usb3_activate;
1496 tunnel->src_port = down;
1497 tunnel->dst_port = up;
1498 tunnel->max_up = max_up;
1499 tunnel->max_down = max_down;
1500
1501 path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0,
1502 "USB3 Down");
1503 if (!path) {
1504 tb_tunnel_free(tunnel);
1505 return NULL;
1506 }
1507 tb_usb3_init_path(path);
1508 tunnel->paths[TB_USB3_PATH_DOWN] = path;
1509
1510 path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0,
1511 "USB3 Up");
1512 if (!path) {
1513 tb_tunnel_free(tunnel);
1514 return NULL;
1515 }
1516 tb_usb3_init_path(path);
1517 tunnel->paths[TB_USB3_PATH_UP] = path;
1518
1519 if (!tb_route(down->sw)) {
1520 tunnel->allocated_up = max_rate;
1521 tunnel->allocated_down = max_rate;
1522
1523 tunnel->init = tb_usb3_init;
1524 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1525 tunnel->release_unused_bandwidth =
1526 tb_usb3_release_unused_bandwidth;
1527 tunnel->reclaim_available_bandwidth =
1528 tb_usb3_reclaim_available_bandwidth;
1529 }
1530
1531 return tunnel;
1532 }
1533
1534 /**
1535 * tb_tunnel_free() - free a tunnel
1536 * @tunnel: Tunnel to be freed
1537 *
1538 * Frees a tunnel. The tunnel does not need to be deactivated.
1539 */
tb_tunnel_free(struct tb_tunnel * tunnel)1540 void tb_tunnel_free(struct tb_tunnel *tunnel)
1541 {
1542 int i;
1543
1544 if (!tunnel)
1545 return;
1546
1547 if (tunnel->deinit)
1548 tunnel->deinit(tunnel);
1549
1550 for (i = 0; i < tunnel->npaths; i++) {
1551 if (tunnel->paths[i])
1552 tb_path_free(tunnel->paths[i]);
1553 }
1554
1555 kfree(tunnel->paths);
1556 kfree(tunnel);
1557 }
1558
1559 /**
1560 * tb_tunnel_is_invalid - check whether an activated path is still valid
1561 * @tunnel: Tunnel to check
1562 */
tb_tunnel_is_invalid(struct tb_tunnel * tunnel)1563 bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
1564 {
1565 int i;
1566
1567 for (i = 0; i < tunnel->npaths; i++) {
1568 WARN_ON(!tunnel->paths[i]->activated);
1569 if (tb_path_is_invalid(tunnel->paths[i]))
1570 return true;
1571 }
1572
1573 return false;
1574 }
1575
1576 /**
1577 * tb_tunnel_restart() - activate a tunnel after a hardware reset
1578 * @tunnel: Tunnel to restart
1579 *
1580 * Return: 0 on success and negative errno in case if failure
1581 */
tb_tunnel_restart(struct tb_tunnel * tunnel)1582 int tb_tunnel_restart(struct tb_tunnel *tunnel)
1583 {
1584 int res, i;
1585
1586 tb_tunnel_dbg(tunnel, "activating\n");
1587
1588 /*
1589 * Make sure all paths are properly disabled before enabling
1590 * them again.
1591 */
1592 for (i = 0; i < tunnel->npaths; i++) {
1593 if (tunnel->paths[i]->activated) {
1594 tb_path_deactivate(tunnel->paths[i]);
1595 tunnel->paths[i]->activated = false;
1596 }
1597 }
1598
1599 if (tunnel->init) {
1600 res = tunnel->init(tunnel);
1601 if (res)
1602 return res;
1603 }
1604
1605 for (i = 0; i < tunnel->npaths; i++) {
1606 res = tb_path_activate(tunnel->paths[i]);
1607 if (res)
1608 goto err;
1609 }
1610
1611 if (tunnel->activate) {
1612 res = tunnel->activate(tunnel, true);
1613 if (res)
1614 goto err;
1615 }
1616
1617 return 0;
1618
1619 err:
1620 tb_tunnel_warn(tunnel, "activation failed\n");
1621 tb_tunnel_deactivate(tunnel);
1622 return res;
1623 }
1624
1625 /**
1626 * tb_tunnel_activate() - activate a tunnel
1627 * @tunnel: Tunnel to activate
1628 *
1629 * Return: Returns 0 on success or an error code on failure.
1630 */
tb_tunnel_activate(struct tb_tunnel * tunnel)1631 int tb_tunnel_activate(struct tb_tunnel *tunnel)
1632 {
1633 int i;
1634
1635 for (i = 0; i < tunnel->npaths; i++) {
1636 if (tunnel->paths[i]->activated) {
1637 tb_tunnel_WARN(tunnel,
1638 "trying to activate an already activated tunnel\n");
1639 return -EINVAL;
1640 }
1641 }
1642
1643 return tb_tunnel_restart(tunnel);
1644 }
1645
1646 /**
1647 * tb_tunnel_deactivate() - deactivate a tunnel
1648 * @tunnel: Tunnel to deactivate
1649 */
tb_tunnel_deactivate(struct tb_tunnel * tunnel)1650 void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
1651 {
1652 int i;
1653
1654 tb_tunnel_dbg(tunnel, "deactivating\n");
1655
1656 if (tunnel->activate)
1657 tunnel->activate(tunnel, false);
1658
1659 for (i = 0; i < tunnel->npaths; i++) {
1660 if (tunnel->paths[i] && tunnel->paths[i]->activated)
1661 tb_path_deactivate(tunnel->paths[i]);
1662 }
1663 }
1664
1665 /**
1666 * tb_tunnel_port_on_path() - Does the tunnel go through port
1667 * @tunnel: Tunnel to check
1668 * @port: Port to check
1669 *
1670 * Returns true if @tunnel goes through @port (direction does not matter),
1671 * false otherwise.
1672 */
tb_tunnel_port_on_path(const struct tb_tunnel * tunnel,const struct tb_port * port)1673 bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
1674 const struct tb_port *port)
1675 {
1676 int i;
1677
1678 for (i = 0; i < tunnel->npaths; i++) {
1679 if (!tunnel->paths[i])
1680 continue;
1681
1682 if (tb_path_port_on_path(tunnel->paths[i], port))
1683 return true;
1684 }
1685
1686 return false;
1687 }
1688
tb_tunnel_is_active(const struct tb_tunnel * tunnel)1689 static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
1690 {
1691 int i;
1692
1693 for (i = 0; i < tunnel->npaths; i++) {
1694 if (!tunnel->paths[i])
1695 return false;
1696 if (!tunnel->paths[i]->activated)
1697 return false;
1698 }
1699
1700 return true;
1701 }
1702
1703 /**
1704 * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
1705 * @tunnel: Tunnel to check
1706 * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port.
1707 * Can be %NULL.
1708 * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port.
1709 * Can be %NULL.
1710 *
1711 * Stores the amount of isochronous bandwidth @tunnel consumes in
1712 * @consumed_up and @consumed_down. In case of success returns %0,
1713 * negative errno otherwise.
1714 */
tb_tunnel_consumed_bandwidth(struct tb_tunnel * tunnel,int * consumed_up,int * consumed_down)1715 int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
1716 int *consumed_down)
1717 {
1718 int up_bw = 0, down_bw = 0;
1719
1720 if (!tb_tunnel_is_active(tunnel))
1721 goto out;
1722
1723 if (tunnel->consumed_bandwidth) {
1724 int ret;
1725
1726 ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw);
1727 if (ret)
1728 return ret;
1729
1730 tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw,
1731 down_bw);
1732 }
1733
1734 out:
1735 if (consumed_up)
1736 *consumed_up = up_bw;
1737 if (consumed_down)
1738 *consumed_down = down_bw;
1739
1740 return 0;
1741 }
1742
1743 /**
1744 * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth
1745 * @tunnel: Tunnel whose unused bandwidth to release
1746 *
1747 * If tunnel supports dynamic bandwidth management (USB3 tunnels at the
1748 * moment) this function makes it to release all the unused bandwidth.
1749 *
1750 * Returns %0 in case of success and negative errno otherwise.
1751 */
tb_tunnel_release_unused_bandwidth(struct tb_tunnel * tunnel)1752 int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel)
1753 {
1754 if (!tb_tunnel_is_active(tunnel))
1755 return 0;
1756
1757 if (tunnel->release_unused_bandwidth) {
1758 int ret;
1759
1760 ret = tunnel->release_unused_bandwidth(tunnel);
1761 if (ret)
1762 return ret;
1763 }
1764
1765 return 0;
1766 }
1767
1768 /**
1769 * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth
1770 * @tunnel: Tunnel reclaiming available bandwidth
1771 * @available_up: Available upstream bandwidth (in Mb/s)
1772 * @available_down: Available downstream bandwidth (in Mb/s)
1773 *
1774 * Reclaims bandwidth from @available_up and @available_down and updates
1775 * the variables accordingly (e.g decreases both according to what was
1776 * reclaimed by the tunnel). If nothing was reclaimed the values are
1777 * kept as is.
1778 */
tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel * tunnel,int * available_up,int * available_down)1779 void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
1780 int *available_up,
1781 int *available_down)
1782 {
1783 if (!tb_tunnel_is_active(tunnel))
1784 return;
1785
1786 if (tunnel->reclaim_available_bandwidth)
1787 tunnel->reclaim_available_bandwidth(tunnel, available_up,
1788 available_down);
1789 }
1790