tunnel.c 36.0 KB
Newer Older
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 11 12
#include <linux/slab.h>
#include <linux/list.h>

13
#include "tunnel.h"
14 15
#include "tb.h"

16 17 18
/* PCIe adapters use always HopID of 8 for both directions */
#define TB_PCI_HOPID			8

19 20 21
#define TB_PCI_PATH_DOWN		0
#define TB_PCI_PATH_UP			1

22 23 24 25 26 27
/* USB3 adapters use always HopID of 8 for both directions */
#define TB_USB3_HOPID			8

#define TB_USB3_PATH_DOWN		0
#define TB_USB3_PATH_UP			1

28 29 30 31 32 33 34 35 36
/* DP adapters use HopID 8 for AUX and 9 for Video */
#define TB_DP_AUX_TX_HOPID		8
#define TB_DP_AUX_RX_HOPID		8
#define TB_DP_VIDEO_HOPID		9

#define TB_DP_VIDEO_PATH_OUT		0
#define TB_DP_AUX_PATH_OUT		1
#define TB_DP_AUX_PATH_IN		2

37 38 39
#define TB_DMA_PATH_OUT			0
#define TB_DMA_PATH_IN			1

40
static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };
41

42 43
#define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...)                   \
	do {                                                            \
44
		struct tb_tunnel *__tunnel = (tunnel);                  \
45
		level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt,   \
46 47 48 49
		      tb_route(__tunnel->src_port->sw),                 \
		      __tunnel->src_port->port,                         \
		      tb_route(__tunnel->dst_port->sw),                 \
		      __tunnel->dst_port->port,                         \
50
		      tb_tunnel_names[__tunnel->type],			\
51 52 53 54 55 56 57 58 59
		      ## arg);                                          \
	} while (0)

#define tb_tunnel_WARN(tunnel, fmt, arg...) \
	__TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
#define tb_tunnel_warn(tunnel, fmt, arg...) \
	__TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
#define tb_tunnel_info(tunnel, fmt, arg...) \
	__TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
60 61
#define tb_tunnel_dbg(tunnel, fmt, arg...) \
	__TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
62

63 64
static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
					 enum tb_tunnel_type type)
65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80
{
	struct tb_tunnel *tunnel;

	tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
	if (!tunnel)
		return NULL;

	tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
	if (!tunnel->paths) {
		tb_tunnel_free(tunnel);
		return NULL;
	}

	INIT_LIST_HEAD(&tunnel->list);
	tunnel->tb = tb;
	tunnel->npaths = npaths;
81
	tunnel->type = type;
82 83 84 85 86 87 88 89 90 91 92 93

	return tunnel;
}

static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
{
	int res;

	res = tb_pci_port_enable(tunnel->src_port, activate);
	if (res)
		return res;

94 95 96 97
	if (tb_port_is_pcie_up(tunnel->dst_port))
		return tb_pci_port_enable(tunnel->dst_port, activate);

	return 0;
98 99
}

100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115
static int tb_initial_credits(const struct tb_switch *sw)
{
	/* If the path is complete sw is not NULL */
	if (sw) {
		/* More credits for faster link */
		switch (sw->link_speed * sw->link_width) {
		case 40:
			return 32;
		case 20:
			return 24;
		}
	}

	return 16;
}

116 117 118 119 120 121 122 123 124 125
static void tb_pci_init_path(struct tb_path *path)
{
	path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
	path->egress_shared_buffer = TB_PATH_NONE;
	path->ingress_fc_enable = TB_PATH_ALL;
	path->ingress_shared_buffer = TB_PATH_NONE;
	path->priority = 3;
	path->weight = 1;
	path->drop_packages = 0;
	path->nfc_credits = 0;
126
	path->hops[0].initial_credits = 7;
127 128 129
	if (path->path_length > 1)
		path->hops[1].initial_credits =
			tb_initial_credits(path->hops[1].in_port->sw);
130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148
}

/**
 * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
 * @tb: Pointer to the domain structure
 * @down: PCIe downstream adapter
 *
 * If @down adapter is active, follows the tunnel to the PCIe upstream
 * adapter and back. Returns the discovered tunnel or %NULL if there was
 * no tunnel.
 */
struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
{
	struct tb_tunnel *tunnel;
	struct tb_path *path;

	if (!tb_pci_port_is_enabled(down))
		return NULL;

149
	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204
	if (!tunnel)
		return NULL;

	tunnel->activate = tb_pci_activate;
	tunnel->src_port = down;

	/*
	 * Discover both paths even if they are not complete. We will
	 * clean them up by calling tb_tunnel_deactivate() below in that
	 * case.
	 */
	path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
				&tunnel->dst_port, "PCIe Up");
	if (!path) {
		/* Just disable the downstream port */
		tb_pci_port_enable(down, false);
		goto err_free;
	}
	tunnel->paths[TB_PCI_PATH_UP] = path;
	tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]);

	path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
				"PCIe Down");
	if (!path)
		goto err_deactivate;
	tunnel->paths[TB_PCI_PATH_DOWN] = path;
	tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]);

	/* Validate that the tunnel is complete */
	if (!tb_port_is_pcie_up(tunnel->dst_port)) {
		tb_port_warn(tunnel->dst_port,
			     "path does not end on a PCIe adapter, cleaning up\n");
		goto err_deactivate;
	}

	if (down != tunnel->src_port) {
		tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
		goto err_deactivate;
	}

	if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
		tb_tunnel_warn(tunnel,
			       "tunnel is not fully activated, cleaning up\n");
		goto err_deactivate;
	}

	tb_tunnel_dbg(tunnel, "discovered\n");
	return tunnel;

err_deactivate:
	tb_tunnel_deactivate(tunnel);
err_free:
	tb_tunnel_free(tunnel);

	return NULL;
205 206 207
}

/**
208 209 210 211
 * tb_tunnel_alloc_pci() - allocate a pci tunnel
 * @tb: Pointer to the domain structure
 * @up: PCIe upstream adapter port
 * @down: PCIe downstream adapter port
212 213 214 215
 *
 * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
 * TB_TYPE_PCIE_DOWN.
 *
216
 * Return: Returns a tb_tunnel on success or NULL on failure.
217
 */
218 219
struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
				      struct tb_port *down)
220
{
221
	struct tb_tunnel *tunnel;
222
	struct tb_path *path;
223

224
	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
225
	if (!tunnel)
226
		return NULL;
227

228 229 230 231
	tunnel->activate = tb_pci_activate;
	tunnel->src_port = down;
	tunnel->dst_port = up;

232 233 234
	path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
			     "PCIe Down");
	if (!path) {
235 236
		tb_tunnel_free(tunnel);
		return NULL;
237
	}
238
	tb_pci_init_path(path);
239
	tunnel->paths[TB_PCI_PATH_DOWN] = path;
240

241 242 243
	path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
			     "PCIe Up");
	if (!path) {
244 245 246
		tb_tunnel_free(tunnel);
		return NULL;
	}
247
	tb_pci_init_path(path);
248
	tunnel->paths[TB_PCI_PATH_UP] = path;
249 250

	return tunnel;
251 252
}

253 254 255 256 257 258
static bool tb_dp_is_usb4(const struct tb_switch *sw)
{
	/* Titan Ridge DP adapters need the same treatment as USB4 */
	return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
}

259 260 261 262 263 264 265
static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
{
	int timeout = 10;
	u32 val;
	int ret;

	/* Both ends need to support this */
266
	if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293
		return 0;

	ret = tb_port_read(out, &val, TB_CFG_PORT,
			   out->cap_adap + DP_STATUS_CTRL, 1);
	if (ret)
		return ret;

	val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;

	ret = tb_port_write(out, &val, TB_CFG_PORT,
			    out->cap_adap + DP_STATUS_CTRL, 1);
	if (ret)
		return ret;

	do {
		ret = tb_port_read(out, &val, TB_CFG_PORT,
				   out->cap_adap + DP_STATUS_CTRL, 1);
		if (ret)
			return ret;
		if (!(val & DP_STATUS_CTRL_CMHS))
			return 0;
		usleep_range(10, 100);
	} while (timeout--);

	return -ETIMEDOUT;
}

294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317
static inline u32 tb_dp_cap_get_rate(u32 val)
{
	u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;

	switch (rate) {
	case DP_COMMON_CAP_RATE_RBR:
		return 1620;
	case DP_COMMON_CAP_RATE_HBR:
		return 2700;
	case DP_COMMON_CAP_RATE_HBR2:
		return 5400;
	case DP_COMMON_CAP_RATE_HBR3:
		return 8100;
	default:
		return 0;
	}
}

static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
{
	val &= ~DP_COMMON_CAP_RATE_MASK;
	switch (rate) {
	default:
		WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
318
		fallthrough;
319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357
	case 1620:
		val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
		break;
	case 2700:
		val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
		break;
	case 5400:
		val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
		break;
	case 8100:
		val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
		break;
	}
	return val;
}

static inline u32 tb_dp_cap_get_lanes(u32 val)
{
	u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;

	switch (lanes) {
	case DP_COMMON_CAP_1_LANE:
		return 1;
	case DP_COMMON_CAP_2_LANES:
		return 2;
	case DP_COMMON_CAP_4_LANES:
		return 4;
	default:
		return 0;
	}
}

static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
{
	val &= ~DP_COMMON_CAP_LANES_MASK;
	switch (lanes) {
	default:
		WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
		     lanes);
358
		fallthrough;
359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420
	case 1:
		val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
		break;
	case 2:
		val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
		break;
	case 4:
		val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
		break;
	}
	return val;
}

static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
{
	/* Tunneling removes the DP 8b/10b encoding */
	return rate * lanes * 8 / 10;
}

static int 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)
{
	static const u32 dp_bw[][2] = {
		/* Mb/s, lanes */
		{ 8100, 4 }, /* 25920 Mb/s */
		{ 5400, 4 }, /* 17280 Mb/s */
		{ 8100, 2 }, /* 12960 Mb/s */
		{ 2700, 4 }, /* 8640 Mb/s */
		{ 5400, 2 }, /* 8640 Mb/s */
		{ 8100, 1 }, /* 6480 Mb/s */
		{ 1620, 4 }, /* 5184 Mb/s */
		{ 5400, 1 }, /* 4320 Mb/s */
		{ 2700, 2 }, /* 4320 Mb/s */
		{ 1620, 2 }, /* 2592 Mb/s */
		{ 2700, 1 }, /* 2160 Mb/s */
		{ 1620, 1 }, /* 1296 Mb/s */
	};
	unsigned int i;

	/*
	 * Find a combination that can fit into max_bw and does not
	 * exceed the maximum rate and lanes supported by the DP OUT and
	 * DP IN adapters.
	 */
	for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
		if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
			continue;

		if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
			continue;

		if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
			*new_rate = dp_bw[i][0];
			*new_lanes = dp_bw[i][1];
			return 0;
		}
	}

	return -ENOSR;
}

421 422
static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
{
423
	u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
424 425
	struct tb_port *out = tunnel->dst_port;
	struct tb_port *in = tunnel->src_port;
426
	int ret, max_bw;
427 428 429 430 431 432 433 434

	/*
	 * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
	 * newer generation hardware.
	 */
	if (in->sw->generation < 2 || out->sw->generation < 2)
		return 0;

435 436 437 438 439 440 441 442
	/*
	 * Perform connection manager handshake between IN and OUT ports
	 * before capabilities exchange can take place.
	 */
	ret = tb_dp_cm_handshake(in, out);
	if (ret)
		return ret;

443 444
	/* Read both DP_LOCAL_CAP registers */
	ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
445
			   in->cap_adap + DP_LOCAL_CAP, 1);
446 447 448 449
	if (ret)
		return ret;

	ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
450
			   out->cap_adap + DP_LOCAL_CAP, 1);
451 452 453 454 455
	if (ret)
		return ret;

	/* Write IN local caps to OUT remote caps */
	ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
456
			    out->cap_adap + DP_REMOTE_CAP, 1);
457 458 459
	if (ret)
		return ret;

460 461 462 463 464 465 466 467 468 469 470 471 472 473 474
	in_rate = tb_dp_cap_get_rate(in_dp_cap);
	in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
	tb_port_dbg(in, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
		    in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));

	/*
	 * If the tunnel bandwidth is limited (max_bw is set) then see
	 * if we need to reduce bandwidth to fit there.
	 */
	out_rate = tb_dp_cap_get_rate(out_dp_cap);
	out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
	bw = tb_dp_bandwidth(out_rate, out_lanes);
	tb_port_dbg(out, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
		    out_rate, out_lanes, bw);

475 476 477 478 479 480
	if (in->sw->config.depth < out->sw->config.depth)
		max_bw = tunnel->max_down;
	else
		max_bw = tunnel->max_up;

	if (max_bw && bw > max_bw) {
481 482
		u32 new_rate, new_lanes, new_bw;

483
		ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes,
484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502
					     out_rate, out_lanes, &new_rate,
					     &new_lanes);
		if (ret) {
			tb_port_info(out, "not enough bandwidth for DP tunnel\n");
			return ret;
		}

		new_bw = tb_dp_bandwidth(new_rate, new_lanes);
		tb_port_dbg(out, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
			    new_rate, new_lanes, new_bw);

		/*
		 * Set new rate and number of lanes before writing it to
		 * the IN port remote caps.
		 */
		out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
		out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
	}

503
	return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
504
			     in->cap_adap + DP_REMOTE_CAP, 1);
505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543
}

static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
{
	int ret;

	if (active) {
		struct tb_path **paths;
		int last;

		paths = tunnel->paths;
		last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;

		tb_dp_port_set_hops(tunnel->src_port,
			paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
			paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
			paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);

		tb_dp_port_set_hops(tunnel->dst_port,
			paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
			paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
			paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
	} else {
		tb_dp_port_hpd_clear(tunnel->src_port);
		tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
		if (tb_port_is_dpout(tunnel->dst_port))
			tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
	}

	ret = tb_dp_port_enable(tunnel->src_port, active);
	if (ret)
		return ret;

	if (tb_port_is_dpout(tunnel->dst_port))
		return tb_dp_port_enable(tunnel->dst_port, active);

	return 0;
}

544 545
static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
				    int *consumed_down)
546 547 548 549 550 551
{
	struct tb_port *in = tunnel->src_port;
	const struct tb_switch *sw = in->sw;
	u32 val, rate = 0, lanes = 0;
	int ret;

552
	if (tb_dp_is_usb4(sw)) {
553
		int timeout = 20;
554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588

		/*
		 * Wait for DPRX done. Normally it should be already set
		 * for active tunnel.
		 */
		do {
			ret = tb_port_read(in, &val, TB_CFG_PORT,
					   in->cap_adap + DP_COMMON_CAP, 1);
			if (ret)
				return ret;

			if (val & DP_COMMON_CAP_DPRX_DONE) {
				rate = tb_dp_cap_get_rate(val);
				lanes = tb_dp_cap_get_lanes(val);
				break;
			}
			msleep(250);
		} while (timeout--);

		if (!timeout)
			return -ETIMEDOUT;
	} else if (sw->generation >= 2) {
		/*
		 * Read from the copied remote cap so that we take into
		 * account if capabilities were reduced during exchange.
		 */
		ret = tb_port_read(in, &val, TB_CFG_PORT,
				   in->cap_adap + DP_REMOTE_CAP, 1);
		if (ret)
			return ret;

		rate = tb_dp_cap_get_rate(val);
		lanes = tb_dp_cap_get_lanes(val);
	} else {
		/* No bandwidth management for legacy devices  */
589 590
		*consumed_up = 0;
		*consumed_down = 0;
591 592 593
		return 0;
	}

594 595 596 597 598 599 600 601 602
	if (in->sw->config.depth < tunnel->dst_port->sw->config.depth) {
		*consumed_up = 0;
		*consumed_down = tb_dp_bandwidth(rate, lanes);
	} else {
		*consumed_up = tb_dp_bandwidth(rate, lanes);
		*consumed_down = 0;
	}

	return 0;
603 604
}

605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631
static void tb_dp_init_aux_path(struct tb_path *path)
{
	int i;

	path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
	path->egress_shared_buffer = TB_PATH_NONE;
	path->ingress_fc_enable = TB_PATH_ALL;
	path->ingress_shared_buffer = TB_PATH_NONE;
	path->priority = 2;
	path->weight = 1;

	for (i = 0; i < path->path_length; i++)
		path->hops[i].initial_credits = 1;
}

static void tb_dp_init_video_path(struct tb_path *path, bool discover)
{
	u32 nfc_credits = path->hops[0].in_port->config.nfc_credits;

	path->egress_fc_enable = TB_PATH_NONE;
	path->egress_shared_buffer = TB_PATH_NONE;
	path->ingress_fc_enable = TB_PATH_NONE;
	path->ingress_shared_buffer = TB_PATH_NONE;
	path->priority = 1;
	path->weight = 1;

	if (discover) {
632
		path->nfc_credits = nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
633 634 635
	} else {
		u32 max_credits;

636 637
		max_credits = (nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
			ADP_CS_4_TOTAL_BUFFERS_SHIFT;
638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668
		/* Leave some credits for AUX path */
		path->nfc_credits = min(max_credits - 2, 12U);
	}
}

/**
 * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
 * @tb: Pointer to the domain structure
 * @in: DP in adapter
 *
 * If @in adapter is active, follows the tunnel to the DP out adapter
 * and back. Returns the discovered tunnel or %NULL if there was no
 * tunnel.
 *
 * Return: DP tunnel or %NULL if no tunnel found.
 */
struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
{
	struct tb_tunnel *tunnel;
	struct tb_port *port;
	struct tb_path *path;

	if (!tb_dp_port_is_enabled(in))
		return NULL;

	tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
	if (!tunnel)
		return NULL;

	tunnel->init = tb_dp_xchg_caps;
	tunnel->activate = tb_dp_activate;
669
	tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727
	tunnel->src_port = in;

	path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
				&tunnel->dst_port, "Video");
	if (!path) {
		/* Just disable the DP IN port */
		tb_dp_port_enable(in, false);
		goto err_free;
	}
	tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
	tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], true);

	path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
	if (!path)
		goto err_deactivate;
	tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
	tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);

	path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
				&port, "AUX RX");
	if (!path)
		goto err_deactivate;
	tunnel->paths[TB_DP_AUX_PATH_IN] = path;
	tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);

	/* Validate that the tunnel is complete */
	if (!tb_port_is_dpout(tunnel->dst_port)) {
		tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
		goto err_deactivate;
	}

	if (!tb_dp_port_is_enabled(tunnel->dst_port))
		goto err_deactivate;

	if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
		goto err_deactivate;

	if (port != tunnel->src_port) {
		tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
		goto err_deactivate;
	}

	tb_tunnel_dbg(tunnel, "discovered\n");
	return tunnel;

err_deactivate:
	tb_tunnel_deactivate(tunnel);
err_free:
	tb_tunnel_free(tunnel);

	return NULL;
}

/**
 * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
 * @tb: Pointer to the domain structure
 * @in: DP in adapter port
 * @out: DP out adapter port
728 729 730 731
 * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0
 *	    if not limited)
 * @max_down: Maximum available downstream bandwidth for the DP tunnel
 *	      (%0 if not limited)
732 733 734 735 736 737 738
 *
 * Allocates a tunnel between @in and @out that is capable of tunneling
 * Display Port traffic.
 *
 * Return: Returns a tb_tunnel on success or NULL on failure.
 */
struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
739 740
				     struct tb_port *out, int max_up,
				     int max_down)
741 742 743 744 745 746 747 748 749 750 751 752 753 754
{
	struct tb_tunnel *tunnel;
	struct tb_path **paths;
	struct tb_path *path;

	if (WARN_ON(!in->cap_adap || !out->cap_adap))
		return NULL;

	tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
	if (!tunnel)
		return NULL;

	tunnel->init = tb_dp_xchg_caps;
	tunnel->activate = tb_dp_activate;
755
	tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
756 757
	tunnel->src_port = in;
	tunnel->dst_port = out;
758 759
	tunnel->max_up = max_up;
	tunnel->max_down = max_down;
760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790

	paths = tunnel->paths;

	path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
			     1, "Video");
	if (!path)
		goto err_free;
	tb_dp_init_video_path(path, false);
	paths[TB_DP_VIDEO_PATH_OUT] = path;

	path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
			     TB_DP_AUX_TX_HOPID, 1, "AUX TX");
	if (!path)
		goto err_free;
	tb_dp_init_aux_path(path);
	paths[TB_DP_AUX_PATH_OUT] = path;

	path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
			     TB_DP_AUX_RX_HOPID, 1, "AUX RX");
	if (!path)
		goto err_free;
	tb_dp_init_aux_path(path);
	paths[TB_DP_AUX_PATH_IN] = path;

	return tunnel;

err_free:
	tb_tunnel_free(tunnel);
	return NULL;
}

791 792 793 794
static u32 tb_dma_credits(struct tb_port *nhi)
{
	u32 max_credits;

795 796
	max_credits = (nhi->config.nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
		ADP_CS_4_TOTAL_BUFFERS_SHIFT;
797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878
	return min(max_credits, 13U);
}

static int tb_dma_activate(struct tb_tunnel *tunnel, bool active)
{
	struct tb_port *nhi = tunnel->src_port;
	u32 credits;

	credits = active ? tb_dma_credits(nhi) : 0;
	return tb_port_set_initial_credits(nhi, credits);
}

static void tb_dma_init_path(struct tb_path *path, unsigned int isb,
			     unsigned int efc, u32 credits)
{
	int i;

	path->egress_fc_enable = efc;
	path->ingress_fc_enable = TB_PATH_ALL;
	path->egress_shared_buffer = TB_PATH_NONE;
	path->ingress_shared_buffer = isb;
	path->priority = 5;
	path->weight = 1;
	path->clear_fc = true;

	for (i = 0; i < path->path_length; i++)
		path->hops[i].initial_credits = credits;
}

/**
 * tb_tunnel_alloc_dma() - allocate a DMA tunnel
 * @tb: Pointer to the domain structure
 * @nhi: Host controller port
 * @dst: Destination null port which the other domain is connected to
 * @transmit_ring: NHI ring number used to send packets towards the
 *		   other domain
 * @transmit_path: HopID used for transmitting packets
 * @receive_ring: NHI ring number used to receive packets from the
 *		  other domain
 * @reveive_path: HopID used for receiving packets
 *
 * Return: Returns a tb_tunnel on success or NULL on failure.
 */
struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
				      struct tb_port *dst, int transmit_ring,
				      int transmit_path, int receive_ring,
				      int receive_path)
{
	struct tb_tunnel *tunnel;
	struct tb_path *path;
	u32 credits;

	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);
	if (!tunnel)
		return NULL;

	tunnel->activate = tb_dma_activate;
	tunnel->src_port = nhi;
	tunnel->dst_port = dst;

	credits = tb_dma_credits(nhi);

	path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX");
	if (!path) {
		tb_tunnel_free(tunnel);
		return NULL;
	}
	tb_dma_init_path(path, TB_PATH_NONE, TB_PATH_SOURCE | TB_PATH_INTERNAL,
			 credits);
	tunnel->paths[TB_DMA_PATH_IN] = path;

	path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX");
	if (!path) {
		tb_tunnel_free(tunnel);
		return NULL;
	}
	tb_dma_init_path(path, TB_PATH_SOURCE, TB_PATH_ALL, credits);
	tunnel->paths[TB_DMA_PATH_OUT] = path;

	return tunnel;
}

879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905
static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down)
{
	int ret, up_max_rate, down_max_rate;

	ret = usb4_usb3_port_max_link_rate(up);
	if (ret < 0)
		return ret;
	up_max_rate = ret;

	ret = usb4_usb3_port_max_link_rate(down);
	if (ret < 0)
		return ret;
	down_max_rate = ret;

	return min(up_max_rate, down_max_rate);
}

static int tb_usb3_init(struct tb_tunnel *tunnel)
{
	tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n",
		      tunnel->allocated_up, tunnel->allocated_down);

	return usb4_usb3_port_allocate_bandwidth(tunnel->src_port,
						 &tunnel->allocated_up,
						 &tunnel->allocated_down);
}

906 907 908 909 910 911 912 913 914 915 916 917 918 919
static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate)
{
	int res;

	res = tb_usb3_port_enable(tunnel->src_port, activate);
	if (res)
		return res;

	if (tb_port_is_usb3_up(tunnel->dst_port))
		return tb_usb3_port_enable(tunnel->dst_port, activate);

	return 0;
}

920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953
static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel,
		int *consumed_up, int *consumed_down)
{
	/*
	 * PCIe tunneling affects the USB3 bandwidth so take that it
	 * into account here.
	 */
	*consumed_up = tunnel->allocated_up * (3 + 1) / 3;
	*consumed_down = tunnel->allocated_down * (3 + 1) / 3;
	return 0;
}

static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel)
{
	int ret;

	ret = usb4_usb3_port_release_bandwidth(tunnel->src_port,
					       &tunnel->allocated_up,
					       &tunnel->allocated_down);
	if (ret)
		return ret;

	tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n",
		      tunnel->allocated_up, tunnel->allocated_down);
	return 0;
}

static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
						int *available_up,
						int *available_down)
{
	int ret, max_rate, allocate_up, allocate_down;

	ret = usb4_usb3_port_actual_link_rate(tunnel->src_port);
954 955
	if (ret < 0) {
		tb_tunnel_warn(tunnel, "failed to read actual link rate\n");
956
		return;
957 958 959 960 961 962 963
	} else if (!ret) {
		/* Use maximum link rate if the link valid is not set */
		ret = usb4_usb3_port_max_link_rate(tunnel->src_port);
		if (ret < 0) {
			tb_tunnel_warn(tunnel, "failed to read maximum link rate\n");
			return;
		}
964
	}
965

966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007
	/*
	 * 90% of the max rate can be allocated for isochronous
	 * transfers.
	 */
	max_rate = ret * 90 / 100;

	/* No need to reclaim if already at maximum */
	if (tunnel->allocated_up >= max_rate &&
	    tunnel->allocated_down >= max_rate)
		return;

	/* Don't go lower than what is already allocated */
	allocate_up = min(max_rate, *available_up);
	if (allocate_up < tunnel->allocated_up)
		allocate_up = tunnel->allocated_up;

	allocate_down = min(max_rate, *available_down);
	if (allocate_down < tunnel->allocated_down)
		allocate_down = tunnel->allocated_down;

	/* If no changes no need to do more */
	if (allocate_up == tunnel->allocated_up &&
	    allocate_down == tunnel->allocated_down)
		return;

	ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up,
						&allocate_down);
	if (ret) {
		tb_tunnel_info(tunnel, "failed to allocate bandwidth\n");
		return;
	}

	tunnel->allocated_up = allocate_up;
	*available_up -= tunnel->allocated_up;

	tunnel->allocated_down = allocate_down;
	*available_down -= tunnel->allocated_down;

	tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n",
		      tunnel->allocated_up, tunnel->allocated_down);
}

1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018
static void tb_usb3_init_path(struct tb_path *path)
{
	path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
	path->egress_shared_buffer = TB_PATH_NONE;
	path->ingress_fc_enable = TB_PATH_ALL;
	path->ingress_shared_buffer = TB_PATH_NONE;
	path->priority = 3;
	path->weight = 3;
	path->drop_packages = 0;
	path->nfc_credits = 0;
	path->hops[0].initial_credits = 7;
1019 1020 1021
	if (path->path_length > 1)
		path->hops[1].initial_credits =
			tb_initial_credits(path->hops[1].in_port->sw);
1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053
}

/**
 * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
 * @tb: Pointer to the domain structure
 * @down: USB3 downstream adapter
 *
 * If @down adapter is active, follows the tunnel to the USB3 upstream
 * adapter and back. Returns the discovered tunnel or %NULL if there was
 * no tunnel.
 */
struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
{
	struct tb_tunnel *tunnel;
	struct tb_path *path;

	if (!tb_usb3_port_is_enabled(down))
		return NULL;

	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
	if (!tunnel)
		return NULL;

	tunnel->activate = tb_usb3_activate;
	tunnel->src_port = down;

	/*
	 * Discover both paths even if they are not complete. We will
	 * clean them up by calling tb_tunnel_deactivate() below in that
	 * case.
	 */
	path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
1054
				&tunnel->dst_port, "USB3 Down");
1055 1056 1057 1058 1059
	if (!path) {
		/* Just disable the downstream port */
		tb_usb3_port_enable(down, false);
		goto err_free;
	}
1060 1061
	tunnel->paths[TB_USB3_PATH_DOWN] = path;
	tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
1062 1063

	path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
1064
				"USB3 Up");
1065 1066
	if (!path)
		goto err_deactivate;
1067 1068
	tunnel->paths[TB_USB3_PATH_UP] = path;
	tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]);
1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087

	/* Validate that the tunnel is complete */
	if (!tb_port_is_usb3_up(tunnel->dst_port)) {
		tb_port_warn(tunnel->dst_port,
			     "path does not end on an USB3 adapter, cleaning up\n");
		goto err_deactivate;
	}

	if (down != tunnel->src_port) {
		tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
		goto err_deactivate;
	}

	if (!tb_usb3_port_is_enabled(tunnel->dst_port)) {
		tb_tunnel_warn(tunnel,
			       "tunnel is not fully activated, cleaning up\n");
		goto err_deactivate;
	}

1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110
	if (!tb_route(down->sw)) {
		int ret;

		/*
		 * Read the initial bandwidth allocation for the first
		 * hop tunnel.
		 */
		ret = usb4_usb3_port_allocated_bandwidth(down,
			&tunnel->allocated_up, &tunnel->allocated_down);
		if (ret)
			goto err_deactivate;

		tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n",
			      tunnel->allocated_up, tunnel->allocated_down);

		tunnel->init = tb_usb3_init;
		tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
		tunnel->release_unused_bandwidth =
			tb_usb3_release_unused_bandwidth;
		tunnel->reclaim_available_bandwidth =
			tb_usb3_reclaim_available_bandwidth;
	}

1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126
	tb_tunnel_dbg(tunnel, "discovered\n");
	return tunnel;

err_deactivate:
	tb_tunnel_deactivate(tunnel);
err_free:
	tb_tunnel_free(tunnel);

	return NULL;
}

/**
 * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel
 * @tb: Pointer to the domain structure
 * @up: USB3 upstream adapter port
 * @down: USB3 downstream adapter port
1127 1128 1129 1130
 * @max_up: Maximum available upstream bandwidth for the USB3 tunnel (%0
 *	    if not limited).
 * @max_down: Maximum available downstream bandwidth for the USB3 tunnel
 *	      (%0 if not limited).
1131 1132 1133 1134 1135 1136 1137
 *
 * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and
 * @TB_TYPE_USB3_DOWN.
 *
 * Return: Returns a tb_tunnel on success or %NULL on failure.
 */
struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
1138 1139
				       struct tb_port *down, int max_up,
				       int max_down)
1140 1141 1142
{
	struct tb_tunnel *tunnel;
	struct tb_path *path;
1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163
	int max_rate = 0;

	/*
	 * Check that we have enough bandwidth available for the new
	 * USB3 tunnel.
	 */
	if (max_up > 0 || max_down > 0) {
		max_rate = tb_usb3_max_link_rate(down, up);
		if (max_rate < 0)
			return NULL;

		/* Only 90% can be allocated for USB3 isochronous transfers */
		max_rate = max_rate * 90 / 100;
		tb_port_dbg(up, "required bandwidth for USB3 tunnel %d Mb/s\n",
			    max_rate);

		if (max_rate > max_up || max_rate > max_down) {
			tb_port_warn(up, "not enough bandwidth for USB3 tunnel\n");
			return NULL;
		}
	}
1164 1165 1166 1167 1168 1169 1170 1171

	tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
	if (!tunnel)
		return NULL;

	tunnel->activate = tb_usb3_activate;
	tunnel->src_port = down;
	tunnel->dst_port = up;
1172 1173
	tunnel->max_up = max_up;
	tunnel->max_down = max_down;
1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192

	path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0,
			     "USB3 Down");
	if (!path) {
		tb_tunnel_free(tunnel);
		return NULL;
	}
	tb_usb3_init_path(path);
	tunnel->paths[TB_USB3_PATH_DOWN] = path;

	path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0,
			     "USB3 Up");
	if (!path) {
		tb_tunnel_free(tunnel);
		return NULL;
	}
	tb_usb3_init_path(path);
	tunnel->paths[TB_USB3_PATH_UP] = path;

1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204
	if (!tb_route(down->sw)) {
		tunnel->allocated_up = max_rate;
		tunnel->allocated_down = max_rate;

		tunnel->init = tb_usb3_init;
		tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
		tunnel->release_unused_bandwidth =
			tb_usb3_release_unused_bandwidth;
		tunnel->reclaim_available_bandwidth =
			tb_usb3_reclaim_available_bandwidth;
	}

1205 1206 1207
	return tunnel;
}

1208
/**
1209 1210
 * tb_tunnel_free() - free a tunnel
 * @tunnel: Tunnel to be freed
1211
 *
1212
 * Frees a tunnel. The tunnel does not need to be deactivated.
1213
 */
1214
void tb_tunnel_free(struct tb_tunnel *tunnel)
1215
{
1216 1217 1218
	int i;

	if (!tunnel)
1219
		return;
1220 1221 1222 1223 1224 1225 1226

	for (i = 0; i < tunnel->npaths; i++) {
		if (tunnel->paths[i])
			tb_path_free(tunnel->paths[i]);
	}

	kfree(tunnel->paths);
1227 1228 1229 1230
	kfree(tunnel);
}

/**
1231 1232
 * tb_tunnel_is_invalid - check whether an activated path is still valid
 * @tunnel: Tunnel to check
1233
 */
1234
bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
1235
{
1236
	int i;
1237

1238 1239 1240 1241 1242
	for (i = 0; i < tunnel->npaths; i++) {
		WARN_ON(!tunnel->paths[i]->activated);
		if (tb_path_is_invalid(tunnel->paths[i]))
			return true;
	}
1243

1244
	return false;
1245 1246 1247
}

/**
1248 1249 1250 1251
 * tb_tunnel_restart() - activate a tunnel after a hardware reset
 * @tunnel: Tunnel to restart
 *
 * Return: 0 on success and negative errno in case if failure
1252
 */
1253
int tb_tunnel_restart(struct tb_tunnel *tunnel)
1254
{
1255
	int res, i;
1256

1257
	tb_tunnel_dbg(tunnel, "activating\n");
1258

1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269
	/*
	 * Make sure all paths are properly disabled before enabling
	 * them again.
	 */
	for (i = 0; i < tunnel->npaths; i++) {
		if (tunnel->paths[i]->activated) {
			tb_path_deactivate(tunnel->paths[i]);
			tunnel->paths[i]->activated = false;
		}
	}

1270 1271 1272 1273 1274 1275
	if (tunnel->init) {
		res = tunnel->init(tunnel);
		if (res)
			return res;
	}

1276 1277 1278 1279 1280
	for (i = 0; i < tunnel->npaths; i++) {
		res = tb_path_activate(tunnel->paths[i]);
		if (res)
			goto err;
	}
1281

1282 1283 1284 1285 1286
	if (tunnel->activate) {
		res = tunnel->activate(tunnel, true);
		if (res)
			goto err;
	}
1287 1288

	return 0;
1289

1290 1291
err:
	tb_tunnel_warn(tunnel, "activation failed\n");
1292
	tb_tunnel_deactivate(tunnel);
1293 1294 1295 1296
	return res;
}

/**
1297 1298
 * tb_tunnel_activate() - activate a tunnel
 * @tunnel: Tunnel to activate
1299 1300 1301
 *
 * Return: Returns 0 on success or an error code on failure.
 */
1302
int tb_tunnel_activate(struct tb_tunnel *tunnel)
1303
{
1304
	int i;
1305

1306 1307 1308 1309 1310 1311 1312
	for (i = 0; i < tunnel->npaths; i++) {
		if (tunnel->paths[i]->activated) {
			tb_tunnel_WARN(tunnel,
				       "trying to activate an already activated tunnel\n");
			return -EINVAL;
		}
	}
1313

1314 1315
	return tb_tunnel_restart(tunnel);
}
1316 1317

/**
1318 1319
 * tb_tunnel_deactivate() - deactivate a tunnel
 * @tunnel: Tunnel to deactivate
1320
 */
1321
void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
1322
{
1323 1324
	int i;

1325
	tb_tunnel_dbg(tunnel, "deactivating\n");
1326

1327 1328 1329 1330
	if (tunnel->activate)
		tunnel->activate(tunnel, false);

	for (i = 0; i < tunnel->npaths; i++) {
1331
		if (tunnel->paths[i] && tunnel->paths[i]->activated)
1332 1333 1334
			tb_path_deactivate(tunnel->paths[i]);
	}
}
1335 1336

/**
1337
 * tb_tunnel_port_on_path() - Does the tunnel go through port
1338
 * @tunnel: Tunnel to check
1339
 * @port: Port to check
1340
 *
1341
 * Returns true if @tunnel goes through @port (direction does not matter),
1342 1343
 * false otherwise.
 */
1344 1345
bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
			    const struct tb_port *port)
1346 1347 1348 1349 1350 1351
{
	int i;

	for (i = 0; i < tunnel->npaths; i++) {
		if (!tunnel->paths[i])
			continue;
1352 1353

		if (tb_path_port_on_path(tunnel->paths[i], port))
1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376
			return true;
	}

	return false;
}

static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
{
	int i;

	for (i = 0; i < tunnel->npaths; i++) {
		if (!tunnel->paths[i])
			return false;
		if (!tunnel->paths[i]->activated)
			return false;
	}

	return true;
}

/**
 * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
 * @tunnel: Tunnel to check
1377 1378 1379 1380
 * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port.
 *		 Can be %NULL.
 * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port.
 *		   Can be %NULL.
1381
 *
1382 1383 1384
 * Stores the amount of isochronous bandwidth @tunnel consumes in
 * @consumed_up and @consumed_down. In case of success returns %0,
 * negative errno otherwise.
1385
 */
1386 1387
int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
				 int *consumed_down)
1388
{
1389 1390
	int up_bw = 0, down_bw = 0;

1391
	if (!tb_tunnel_is_active(tunnel))
1392
		goto out;
1393 1394

	if (tunnel->consumed_bandwidth) {
1395
		int ret;
1396

1397 1398 1399 1400 1401 1402
		ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw);
		if (ret)
			return ret;

		tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw,
			      down_bw);
1403 1404
	}

1405 1406 1407 1408 1409 1410
out:
	if (consumed_up)
		*consumed_up = up_bw;
	if (consumed_down)
		*consumed_down = down_bw;

1411 1412
	return 0;
}
1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460

/**
 * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth
 * @tunnel: Tunnel whose unused bandwidth to release
 *
 * If tunnel supports dynamic bandwidth management (USB3 tunnels at the
 * moment) this function makes it to release all the unused bandwidth.
 *
 * Returns %0 in case of success and negative errno otherwise.
 */
int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel)
{
	if (!tb_tunnel_is_active(tunnel))
		return 0;

	if (tunnel->release_unused_bandwidth) {
		int ret;

		ret = tunnel->release_unused_bandwidth(tunnel);
		if (ret)
			return ret;
	}

	return 0;
}

/**
 * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth
 * @tunnel: Tunnel reclaiming available bandwidth
 * @available_up: Available upstream bandwidth (in Mb/s)
 * @available_down: Available downstream bandwidth (in Mb/s)
 *
 * Reclaims bandwidth from @available_up and @available_down and updates
 * the variables accordingly (e.g decreases both according to what was
 * reclaimed by the tunnel). If nothing was reclaimed the values are
 * kept as is.
 */
void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
					   int *available_up,
					   int *available_down)
{
	if (!tb_tunnel_is_active(tunnel))
		return;

	if (tunnel->reclaim_available_bandwidth)
		tunnel->reclaim_available_bandwidth(tunnel, available_up,
						    available_down);
}