xref: /linux/drivers/thunderbolt/usb4.c (revision 52990390f91c1c39ca742fc8f390b29891d95127)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * USB4 specific functionality
4  *
5  * Copyright (C) 2019, Intel Corporation
6  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
7  *	    Rajmohan Mani <rajmohan.mani@intel.com>
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/ktime.h>
12 #include <linux/units.h>
13 
14 #include "sb_regs.h"
15 #include "tb.h"
16 
17 #define USB4_DATA_RETRIES		3
18 
19 enum usb4_sb_target {
20 	USB4_SB_TARGET_ROUTER,
21 	USB4_SB_TARGET_PARTNER,
22 	USB4_SB_TARGET_RETIMER,
23 };
24 
25 #define USB4_NVM_READ_OFFSET_MASK	GENMASK(23, 2)
26 #define USB4_NVM_READ_OFFSET_SHIFT	2
27 #define USB4_NVM_READ_LENGTH_MASK	GENMASK(27, 24)
28 #define USB4_NVM_READ_LENGTH_SHIFT	24
29 
30 #define USB4_NVM_SET_OFFSET_MASK	USB4_NVM_READ_OFFSET_MASK
31 #define USB4_NVM_SET_OFFSET_SHIFT	USB4_NVM_READ_OFFSET_SHIFT
32 
33 #define USB4_DROM_ADDRESS_MASK		GENMASK(14, 2)
34 #define USB4_DROM_ADDRESS_SHIFT		2
35 #define USB4_DROM_SIZE_MASK		GENMASK(19, 15)
36 #define USB4_DROM_SIZE_SHIFT		15
37 
38 #define USB4_NVM_SECTOR_SIZE_MASK	GENMASK(23, 0)
39 
40 #define USB4_BA_LENGTH_MASK		GENMASK(7, 0)
41 #define USB4_BA_INDEX_MASK		GENMASK(15, 0)
42 
43 enum usb4_ba_index {
44 	USB4_BA_MAX_USB3 = 0x1,
45 	USB4_BA_MIN_DP_AUX = 0x2,
46 	USB4_BA_MIN_DP_MAIN = 0x3,
47 	USB4_BA_MAX_PCIE = 0x4,
48 	USB4_BA_MAX_HI = 0x5,
49 };
50 
51 #define USB4_BA_VALUE_MASK		GENMASK(31, 16)
52 #define USB4_BA_VALUE_SHIFT		16
53 
54 static int usb4_native_switch_op(struct tb_switch *sw, u16 opcode,
55 				 u32 *metadata, u8 *status,
56 				 const void *tx_data, size_t tx_dwords,
57 				 void *rx_data, size_t rx_dwords)
58 {
59 	u32 val;
60 	int ret;
61 
62 	if (metadata) {
63 		ret = tb_sw_write(sw, metadata, TB_CFG_SWITCH, ROUTER_CS_25, 1);
64 		if (ret)
65 			return ret;
66 	}
67 	if (tx_dwords) {
68 		ret = tb_sw_write(sw, tx_data, TB_CFG_SWITCH, ROUTER_CS_9,
69 				  tx_dwords);
70 		if (ret)
71 			return ret;
72 	}
73 
74 	val = opcode | ROUTER_CS_26_OV;
75 	ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1);
76 	if (ret)
77 		return ret;
78 
79 	ret = tb_switch_wait_for_bit(sw, ROUTER_CS_26, ROUTER_CS_26_OV, 0, 500);
80 	if (ret)
81 		return ret;
82 
83 	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1);
84 	if (ret)
85 		return ret;
86 
87 	if (val & ROUTER_CS_26_ONS)
88 		return -EOPNOTSUPP;
89 
90 	if (status)
91 		*status = (val & ROUTER_CS_26_STATUS_MASK) >>
92 			ROUTER_CS_26_STATUS_SHIFT;
93 
94 	if (metadata) {
95 		ret = tb_sw_read(sw, metadata, TB_CFG_SWITCH, ROUTER_CS_25, 1);
96 		if (ret)
97 			return ret;
98 	}
99 	if (rx_dwords) {
100 		ret = tb_sw_read(sw, rx_data, TB_CFG_SWITCH, ROUTER_CS_9,
101 				 rx_dwords);
102 		if (ret)
103 			return ret;
104 	}
105 
106 	return 0;
107 }
108 
109 static int __usb4_switch_op(struct tb_switch *sw, u16 opcode, u32 *metadata,
110 			    u8 *status, const void *tx_data, size_t tx_dwords,
111 			    void *rx_data, size_t rx_dwords)
112 {
113 	const struct tb_cm_ops *cm_ops = sw->tb->cm_ops;
114 
115 	if (tx_dwords > NVM_DATA_DWORDS || rx_dwords > NVM_DATA_DWORDS)
116 		return -EINVAL;
117 
118 	/*
119 	 * If the connection manager implementation provides USB4 router
120 	 * operation proxy callback, call it here instead of running the
121 	 * operation natively.
122 	 */
123 	if (cm_ops->usb4_switch_op) {
124 		int ret;
125 
126 		ret = cm_ops->usb4_switch_op(sw, opcode, metadata, status,
127 					     tx_data, tx_dwords, rx_data,
128 					     rx_dwords);
129 		if (ret != -EOPNOTSUPP)
130 			return ret;
131 
132 		/*
133 		 * If the proxy was not supported then run the native
134 		 * router operation instead.
135 		 */
136 	}
137 
138 	return usb4_native_switch_op(sw, opcode, metadata, status, tx_data,
139 				     tx_dwords, rx_data, rx_dwords);
140 }
141 
142 static inline int usb4_switch_op(struct tb_switch *sw, u16 opcode,
143 				 u32 *metadata, u8 *status)
144 {
145 	return __usb4_switch_op(sw, opcode, metadata, status, NULL, 0, NULL, 0);
146 }
147 
148 static inline int usb4_switch_op_data(struct tb_switch *sw, u16 opcode,
149 				      u32 *metadata, u8 *status,
150 				      const void *tx_data, size_t tx_dwords,
151 				      void *rx_data, size_t rx_dwords)
152 {
153 	return __usb4_switch_op(sw, opcode, metadata, status, tx_data,
154 				tx_dwords, rx_data, rx_dwords);
155 }
156 
157 static void usb4_switch_check_wakes(struct tb_switch *sw)
158 {
159 	bool wakeup_usb4 = false;
160 	struct usb4_port *usb4;
161 	struct tb_port *port;
162 	bool wakeup = false;
163 	u32 val;
164 
165 	if (!device_may_wakeup(&sw->dev))
166 		return;
167 
168 	if (tb_route(sw)) {
169 		if (tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_6, 1))
170 			return;
171 
172 		tb_sw_dbg(sw, "PCIe wake: %s, USB3 wake: %s\n",
173 			  (val & ROUTER_CS_6_WOPS) ? "yes" : "no",
174 			  (val & ROUTER_CS_6_WOUS) ? "yes" : "no");
175 
176 		wakeup = val & (ROUTER_CS_6_WOPS | ROUTER_CS_6_WOUS);
177 	}
178 
179 	/*
180 	 * Check for any downstream ports for USB4 wake,
181 	 * connection wake and disconnection wake.
182 	 */
183 	tb_switch_for_each_port(sw, port) {
184 		if (!port->cap_usb4)
185 			continue;
186 
187 		if (tb_port_read(port, &val, TB_CFG_PORT,
188 				 port->cap_usb4 + PORT_CS_18, 1))
189 			break;
190 
191 		tb_port_dbg(port, "USB4 wake: %s, connection wake: %s, disconnection wake: %s\n",
192 			    (val & PORT_CS_18_WOU4S) ? "yes" : "no",
193 			    (val & PORT_CS_18_WOCS) ? "yes" : "no",
194 			    (val & PORT_CS_18_WODS) ? "yes" : "no");
195 
196 		wakeup_usb4 = val & (PORT_CS_18_WOU4S | PORT_CS_18_WOCS |
197 				     PORT_CS_18_WODS);
198 
199 		usb4 = port->usb4;
200 		if (device_may_wakeup(&usb4->dev) && wakeup_usb4)
201 			pm_wakeup_event(&usb4->dev, 0);
202 
203 		wakeup |= wakeup_usb4;
204 	}
205 
206 	if (wakeup)
207 		pm_wakeup_event(&sw->dev, 0);
208 }
209 
210 static bool link_is_usb4(struct tb_port *port)
211 {
212 	u32 val;
213 
214 	if (!port->cap_usb4)
215 		return false;
216 
217 	if (tb_port_read(port, &val, TB_CFG_PORT,
218 			 port->cap_usb4 + PORT_CS_18, 1))
219 		return false;
220 
221 	return !(val & PORT_CS_18_TCM);
222 }
223 
224 /**
225  * usb4_switch_setup() - Additional setup for USB4 device
226  * @sw: USB4 router to setup
227  *
228  * USB4 routers need additional settings in order to enable all the
229  * tunneling. This function enables USB and PCIe tunneling if it can be
230  * enabled (e.g the parent switch also supports them). If USB tunneling
231  * is not available for some reason (like that there is Thunderbolt 3
232  * switch upstream) then the internal xHCI controller is enabled
233  * instead.
234  */
235 int usb4_switch_setup(struct tb_switch *sw)
236 {
237 	struct tb_port *downstream_port;
238 	struct tb_switch *parent;
239 	bool tbt3, xhci;
240 	u32 val = 0;
241 	int ret;
242 
243 	usb4_switch_check_wakes(sw);
244 
245 	if (!tb_route(sw))
246 		return 0;
247 
248 	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_6, 1);
249 	if (ret)
250 		return ret;
251 
252 	parent = tb_switch_parent(sw);
253 	downstream_port = tb_port_at(tb_route(sw), parent);
254 	sw->link_usb4 = link_is_usb4(downstream_port);
255 	tb_sw_dbg(sw, "link: %s\n", sw->link_usb4 ? "USB4" : "TBT");
256 
257 	xhci = val & ROUTER_CS_6_HCI;
258 	tbt3 = !(val & ROUTER_CS_6_TNS);
259 
260 	tb_sw_dbg(sw, "TBT3 support: %s, xHCI: %s\n",
261 		  tbt3 ? "yes" : "no", xhci ? "yes" : "no");
262 
263 	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
264 	if (ret)
265 		return ret;
266 
267 	if (tb_acpi_may_tunnel_usb3() && sw->link_usb4 &&
268 	    tb_switch_find_port(parent, TB_TYPE_USB3_DOWN)) {
269 		val |= ROUTER_CS_5_UTO;
270 		xhci = false;
271 	}
272 
273 	/*
274 	 * Only enable PCIe tunneling if the parent router supports it
275 	 * and it is not disabled.
276 	 */
277 	if (tb_acpi_may_tunnel_pcie() &&
278 	    tb_switch_find_port(parent, TB_TYPE_PCIE_DOWN)) {
279 		val |= ROUTER_CS_5_PTO;
280 		/*
281 		 * xHCI can be enabled if PCIe tunneling is supported
282 		 * and the parent does not have any USB3 dowstream
283 		 * adapters (so we cannot do USB 3.x tunneling).
284 		 */
285 		if (xhci)
286 			val |= ROUTER_CS_5_HCO;
287 	}
288 
289 	/* TBT3 supported by the CM */
290 	val |= ROUTER_CS_5_C3S;
291 	/* Tunneling configuration is ready now */
292 	val |= ROUTER_CS_5_CV;
293 
294 	ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
295 	if (ret)
296 		return ret;
297 
298 	return tb_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_CR,
299 				      ROUTER_CS_6_CR, 50);
300 }
301 
302 /**
303  * usb4_switch_read_uid() - Read UID from USB4 router
304  * @sw: USB4 router
305  * @uid: UID is stored here
306  *
307  * Reads 64-bit UID from USB4 router config space.
308  */
309 int usb4_switch_read_uid(struct tb_switch *sw, u64 *uid)
310 {
311 	return tb_sw_read(sw, uid, TB_CFG_SWITCH, ROUTER_CS_7, 2);
312 }
313 
314 static int usb4_switch_drom_read_block(void *data,
315 				       unsigned int dwaddress, void *buf,
316 				       size_t dwords)
317 {
318 	struct tb_switch *sw = data;
319 	u8 status = 0;
320 	u32 metadata;
321 	int ret;
322 
323 	metadata = (dwords << USB4_DROM_SIZE_SHIFT) & USB4_DROM_SIZE_MASK;
324 	metadata |= (dwaddress << USB4_DROM_ADDRESS_SHIFT) &
325 		USB4_DROM_ADDRESS_MASK;
326 
327 	ret = usb4_switch_op_data(sw, USB4_SWITCH_OP_DROM_READ, &metadata,
328 				  &status, NULL, 0, buf, dwords);
329 	if (ret)
330 		return ret;
331 
332 	return status ? -EIO : 0;
333 }
334 
335 /**
336  * usb4_switch_drom_read() - Read arbitrary bytes from USB4 router DROM
337  * @sw: USB4 router
338  * @address: Byte address inside DROM to start reading
339  * @buf: Buffer where the DROM content is stored
340  * @size: Number of bytes to read from DROM
341  *
342  * Uses USB4 router operations to read router DROM. For devices this
343  * should always work but for hosts it may return %-EOPNOTSUPP in which
344  * case the host router does not have DROM.
345  */
346 int usb4_switch_drom_read(struct tb_switch *sw, unsigned int address, void *buf,
347 			  size_t size)
348 {
349 	return tb_nvm_read_data(address, buf, size, USB4_DATA_RETRIES,
350 				usb4_switch_drom_read_block, sw);
351 }
352 
353 /**
354  * usb4_switch_lane_bonding_possible() - Are conditions met for lane bonding
355  * @sw: USB4 router
356  *
357  * Checks whether conditions are met so that lane bonding can be
358  * established with the upstream router. Call only for device routers.
359  */
360 bool usb4_switch_lane_bonding_possible(struct tb_switch *sw)
361 {
362 	struct tb_port *up;
363 	int ret;
364 	u32 val;
365 
366 	up = tb_upstream_port(sw);
367 	ret = tb_port_read(up, &val, TB_CFG_PORT, up->cap_usb4 + PORT_CS_18, 1);
368 	if (ret)
369 		return false;
370 
371 	return !!(val & PORT_CS_18_BE);
372 }
373 
374 /**
375  * usb4_switch_set_wake() - Enabled/disable wake
376  * @sw: USB4 router
377  * @flags: Wakeup flags (%0 to disable)
378  *
379  * Enables/disables router to wake up from sleep.
380  */
381 int usb4_switch_set_wake(struct tb_switch *sw, unsigned int flags)
382 {
383 	struct usb4_port *usb4;
384 	struct tb_port *port;
385 	u64 route = tb_route(sw);
386 	u32 val;
387 	int ret;
388 
389 	/*
390 	 * Enable wakes coming from all USB4 downstream ports (from
391 	 * child routers). For device routers do this also for the
392 	 * upstream USB4 port.
393 	 */
394 	tb_switch_for_each_port(sw, port) {
395 		if (!tb_port_is_null(port))
396 			continue;
397 		if (!route && tb_is_upstream_port(port))
398 			continue;
399 		if (!port->cap_usb4)
400 			continue;
401 
402 		ret = tb_port_read(port, &val, TB_CFG_PORT,
403 				   port->cap_usb4 + PORT_CS_19, 1);
404 		if (ret)
405 			return ret;
406 
407 		val &= ~(PORT_CS_19_WOC | PORT_CS_19_WOD | PORT_CS_19_WOU4);
408 
409 		if (tb_is_upstream_port(port)) {
410 			val |= PORT_CS_19_WOU4;
411 		} else {
412 			bool configured = val & PORT_CS_19_PC;
413 			usb4 = port->usb4;
414 
415 			if (((flags & TB_WAKE_ON_CONNECT) |
416 			      device_may_wakeup(&usb4->dev)) && !configured)
417 				val |= PORT_CS_19_WOC;
418 			if (((flags & TB_WAKE_ON_DISCONNECT) |
419 			      device_may_wakeup(&usb4->dev)) && configured)
420 				val |= PORT_CS_19_WOD;
421 			if ((flags & TB_WAKE_ON_USB4) && configured)
422 				val |= PORT_CS_19_WOU4;
423 		}
424 
425 		ret = tb_port_write(port, &val, TB_CFG_PORT,
426 				    port->cap_usb4 + PORT_CS_19, 1);
427 		if (ret)
428 			return ret;
429 	}
430 
431 	/*
432 	 * Enable wakes from PCIe, USB 3.x and DP on this router. Only
433 	 * needed for device routers.
434 	 */
435 	if (route) {
436 		ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
437 		if (ret)
438 			return ret;
439 
440 		val &= ~(ROUTER_CS_5_WOP | ROUTER_CS_5_WOU | ROUTER_CS_5_WOD);
441 		if (flags & TB_WAKE_ON_USB3)
442 			val |= ROUTER_CS_5_WOU;
443 		if (flags & TB_WAKE_ON_PCIE)
444 			val |= ROUTER_CS_5_WOP;
445 		if (flags & TB_WAKE_ON_DP)
446 			val |= ROUTER_CS_5_WOD;
447 
448 		ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
449 		if (ret)
450 			return ret;
451 	}
452 
453 	return 0;
454 }
455 
456 /**
457  * usb4_switch_set_sleep() - Prepare the router to enter sleep
458  * @sw: USB4 router
459  *
460  * Sets sleep bit for the router. Returns when the router sleep ready
461  * bit has been asserted.
462  */
463 int usb4_switch_set_sleep(struct tb_switch *sw)
464 {
465 	int ret;
466 	u32 val;
467 
468 	/* Set sleep bit and wait for sleep ready to be asserted */
469 	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
470 	if (ret)
471 		return ret;
472 
473 	val |= ROUTER_CS_5_SLP;
474 
475 	ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, ROUTER_CS_5, 1);
476 	if (ret)
477 		return ret;
478 
479 	return tb_switch_wait_for_bit(sw, ROUTER_CS_6, ROUTER_CS_6_SLPR,
480 				      ROUTER_CS_6_SLPR, 500);
481 }
482 
483 /**
484  * usb4_switch_nvm_sector_size() - Return router NVM sector size
485  * @sw: USB4 router
486  *
487  * If the router supports NVM operations this function returns the NVM
488  * sector size in bytes. If NVM operations are not supported returns
489  * %-EOPNOTSUPP.
490  */
491 int usb4_switch_nvm_sector_size(struct tb_switch *sw)
492 {
493 	u32 metadata;
494 	u8 status;
495 	int ret;
496 
497 	ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_SECTOR_SIZE, &metadata,
498 			     &status);
499 	if (ret)
500 		return ret;
501 
502 	if (status)
503 		return status == 0x2 ? -EOPNOTSUPP : -EIO;
504 
505 	return metadata & USB4_NVM_SECTOR_SIZE_MASK;
506 }
507 
508 static int usb4_switch_nvm_read_block(void *data,
509 	unsigned int dwaddress, void *buf, size_t dwords)
510 {
511 	struct tb_switch *sw = data;
512 	u8 status = 0;
513 	u32 metadata;
514 	int ret;
515 
516 	metadata = (dwords << USB4_NVM_READ_LENGTH_SHIFT) &
517 		   USB4_NVM_READ_LENGTH_MASK;
518 	metadata |= (dwaddress << USB4_NVM_READ_OFFSET_SHIFT) &
519 		   USB4_NVM_READ_OFFSET_MASK;
520 
521 	ret = usb4_switch_op_data(sw, USB4_SWITCH_OP_NVM_READ, &metadata,
522 				  &status, NULL, 0, buf, dwords);
523 	if (ret)
524 		return ret;
525 
526 	return status ? -EIO : 0;
527 }
528 
529 /**
530  * usb4_switch_nvm_read() - Read arbitrary bytes from router NVM
531  * @sw: USB4 router
532  * @address: Starting address in bytes
533  * @buf: Read data is placed here
534  * @size: How many bytes to read
535  *
536  * Reads NVM contents of the router. If NVM is not supported returns
537  * %-EOPNOTSUPP.
538  */
539 int usb4_switch_nvm_read(struct tb_switch *sw, unsigned int address, void *buf,
540 			 size_t size)
541 {
542 	return tb_nvm_read_data(address, buf, size, USB4_DATA_RETRIES,
543 				usb4_switch_nvm_read_block, sw);
544 }
545 
546 /**
547  * usb4_switch_nvm_set_offset() - Set NVM write offset
548  * @sw: USB4 router
549  * @address: Start offset
550  *
551  * Explicitly sets NVM write offset. Normally when writing to NVM this
552  * is done automatically by usb4_switch_nvm_write().
553  *
554  * Returns %0 in success and negative errno if there was a failure.
555  */
556 int usb4_switch_nvm_set_offset(struct tb_switch *sw, unsigned int address)
557 {
558 	u32 metadata, dwaddress;
559 	u8 status = 0;
560 	int ret;
561 
562 	dwaddress = address / 4;
563 	metadata = (dwaddress << USB4_NVM_SET_OFFSET_SHIFT) &
564 		   USB4_NVM_SET_OFFSET_MASK;
565 
566 	ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_SET_OFFSET, &metadata,
567 			     &status);
568 	if (ret)
569 		return ret;
570 
571 	return status ? -EIO : 0;
572 }
573 
574 static int usb4_switch_nvm_write_next_block(void *data, unsigned int dwaddress,
575 					    const void *buf, size_t dwords)
576 {
577 	struct tb_switch *sw = data;
578 	u8 status;
579 	int ret;
580 
581 	ret = usb4_switch_op_data(sw, USB4_SWITCH_OP_NVM_WRITE, NULL, &status,
582 				  buf, dwords, NULL, 0);
583 	if (ret)
584 		return ret;
585 
586 	return status ? -EIO : 0;
587 }
588 
589 /**
590  * usb4_switch_nvm_write() - Write to the router NVM
591  * @sw: USB4 router
592  * @address: Start address where to write in bytes
593  * @buf: Pointer to the data to write
594  * @size: Size of @buf in bytes
595  *
596  * Writes @buf to the router NVM using USB4 router operations. If NVM
597  * write is not supported returns %-EOPNOTSUPP.
598  */
599 int usb4_switch_nvm_write(struct tb_switch *sw, unsigned int address,
600 			  const void *buf, size_t size)
601 {
602 	int ret;
603 
604 	ret = usb4_switch_nvm_set_offset(sw, address);
605 	if (ret)
606 		return ret;
607 
608 	return tb_nvm_write_data(address, buf, size, USB4_DATA_RETRIES,
609 				 usb4_switch_nvm_write_next_block, sw);
610 }
611 
612 /**
613  * usb4_switch_nvm_authenticate() - Authenticate new NVM
614  * @sw: USB4 router
615  *
616  * After the new NVM has been written via usb4_switch_nvm_write(), this
617  * function triggers NVM authentication process. The router gets power
618  * cycled and if the authentication is successful the new NVM starts
619  * running. In case of failure returns negative errno.
620  *
621  * The caller should call usb4_switch_nvm_authenticate_status() to read
622  * the status of the authentication after power cycle. It should be the
623  * first router operation to avoid the status being lost.
624  */
625 int usb4_switch_nvm_authenticate(struct tb_switch *sw)
626 {
627 	int ret;
628 
629 	ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_AUTH, NULL, NULL);
630 	switch (ret) {
631 	/*
632 	 * The router is power cycled once NVM_AUTH is started so it is
633 	 * expected to get any of the following errors back.
634 	 */
635 	case -EACCES:
636 	case -ENOTCONN:
637 	case -ETIMEDOUT:
638 		return 0;
639 
640 	default:
641 		return ret;
642 	}
643 }
644 
645 /**
646  * usb4_switch_nvm_authenticate_status() - Read status of last NVM authenticate
647  * @sw: USB4 router
648  * @status: Status code of the operation
649  *
650  * The function checks if there is status available from the last NVM
651  * authenticate router operation. If there is status then %0 is returned
652  * and the status code is placed in @status. Returns negative errno in case
653  * of failure.
654  *
655  * Must be called before any other router operation.
656  */
657 int usb4_switch_nvm_authenticate_status(struct tb_switch *sw, u32 *status)
658 {
659 	const struct tb_cm_ops *cm_ops = sw->tb->cm_ops;
660 	u16 opcode;
661 	u32 val;
662 	int ret;
663 
664 	if (cm_ops->usb4_switch_nvm_authenticate_status) {
665 		ret = cm_ops->usb4_switch_nvm_authenticate_status(sw, status);
666 		if (ret != -EOPNOTSUPP)
667 			return ret;
668 	}
669 
670 	ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1);
671 	if (ret)
672 		return ret;
673 
674 	/* Check that the opcode is correct */
675 	opcode = val & ROUTER_CS_26_OPCODE_MASK;
676 	if (opcode == USB4_SWITCH_OP_NVM_AUTH) {
677 		if (val & ROUTER_CS_26_OV)
678 			return -EBUSY;
679 		if (val & ROUTER_CS_26_ONS)
680 			return -EOPNOTSUPP;
681 
682 		*status = (val & ROUTER_CS_26_STATUS_MASK) >>
683 			ROUTER_CS_26_STATUS_SHIFT;
684 	} else {
685 		*status = 0;
686 	}
687 
688 	return 0;
689 }
690 
691 /**
692  * usb4_switch_credits_init() - Read buffer allocation parameters
693  * @sw: USB4 router
694  *
695  * Reads @sw buffer allocation parameters and initializes @sw buffer
696  * allocation fields accordingly. Specifically @sw->credits_allocation
697  * is set to %true if these parameters can be used in tunneling.
698  *
699  * Returns %0 on success and negative errno otherwise.
700  */
701 int usb4_switch_credits_init(struct tb_switch *sw)
702 {
703 	int max_usb3, min_dp_aux, min_dp_main, max_pcie, max_dma;
704 	int ret, length, i, nports;
705 	const struct tb_port *port;
706 	u32 data[NVM_DATA_DWORDS];
707 	u32 metadata = 0;
708 	u8 status = 0;
709 
710 	memset(data, 0, sizeof(data));
711 	ret = usb4_switch_op_data(sw, USB4_SWITCH_OP_BUFFER_ALLOC, &metadata,
712 				  &status, NULL, 0, data, ARRAY_SIZE(data));
713 	if (ret)
714 		return ret;
715 	if (status)
716 		return -EIO;
717 
718 	length = metadata & USB4_BA_LENGTH_MASK;
719 	if (WARN_ON(length > ARRAY_SIZE(data)))
720 		return -EMSGSIZE;
721 
722 	max_usb3 = -1;
723 	min_dp_aux = -1;
724 	min_dp_main = -1;
725 	max_pcie = -1;
726 	max_dma = -1;
727 
728 	tb_sw_dbg(sw, "credit allocation parameters:\n");
729 
730 	for (i = 0; i < length; i++) {
731 		u16 index, value;
732 
733 		index = data[i] & USB4_BA_INDEX_MASK;
734 		value = (data[i] & USB4_BA_VALUE_MASK) >> USB4_BA_VALUE_SHIFT;
735 
736 		switch (index) {
737 		case USB4_BA_MAX_USB3:
738 			tb_sw_dbg(sw, " USB3: %u\n", value);
739 			max_usb3 = value;
740 			break;
741 		case USB4_BA_MIN_DP_AUX:
742 			tb_sw_dbg(sw, " DP AUX: %u\n", value);
743 			min_dp_aux = value;
744 			break;
745 		case USB4_BA_MIN_DP_MAIN:
746 			tb_sw_dbg(sw, " DP main: %u\n", value);
747 			min_dp_main = value;
748 			break;
749 		case USB4_BA_MAX_PCIE:
750 			tb_sw_dbg(sw, " PCIe: %u\n", value);
751 			max_pcie = value;
752 			break;
753 		case USB4_BA_MAX_HI:
754 			tb_sw_dbg(sw, " DMA: %u\n", value);
755 			max_dma = value;
756 			break;
757 		default:
758 			tb_sw_dbg(sw, " unknown credit allocation index %#x, skipping\n",
759 				  index);
760 			break;
761 		}
762 	}
763 
764 	/*
765 	 * Validate the buffer allocation preferences. If we find
766 	 * issues, log a warning and fall back using the hard-coded
767 	 * values.
768 	 */
769 
770 	/* Host router must report baMaxHI */
771 	if (!tb_route(sw) && max_dma < 0) {
772 		tb_sw_warn(sw, "host router is missing baMaxHI\n");
773 		goto err_invalid;
774 	}
775 
776 	nports = 0;
777 	tb_switch_for_each_port(sw, port) {
778 		if (tb_port_is_null(port))
779 			nports++;
780 	}
781 
782 	/* Must have DP buffer allocation (multiple USB4 ports) */
783 	if (nports > 2 && (min_dp_aux < 0 || min_dp_main < 0)) {
784 		tb_sw_warn(sw, "multiple USB4 ports require baMinDPaux/baMinDPmain\n");
785 		goto err_invalid;
786 	}
787 
788 	tb_switch_for_each_port(sw, port) {
789 		if (tb_port_is_dpout(port) && min_dp_main < 0) {
790 			tb_sw_warn(sw, "missing baMinDPmain");
791 			goto err_invalid;
792 		}
793 		if ((tb_port_is_dpin(port) || tb_port_is_dpout(port)) &&
794 		    min_dp_aux < 0) {
795 			tb_sw_warn(sw, "missing baMinDPaux");
796 			goto err_invalid;
797 		}
798 		if ((tb_port_is_usb3_down(port) || tb_port_is_usb3_up(port)) &&
799 		    max_usb3 < 0) {
800 			tb_sw_warn(sw, "missing baMaxUSB3");
801 			goto err_invalid;
802 		}
803 		if ((tb_port_is_pcie_down(port) || tb_port_is_pcie_up(port)) &&
804 		    max_pcie < 0) {
805 			tb_sw_warn(sw, "missing baMaxPCIe");
806 			goto err_invalid;
807 		}
808 	}
809 
810 	/*
811 	 * Buffer allocation passed the validation so we can use it in
812 	 * path creation.
813 	 */
814 	sw->credit_allocation = true;
815 	if (max_usb3 > 0)
816 		sw->max_usb3_credits = max_usb3;
817 	if (min_dp_aux > 0)
818 		sw->min_dp_aux_credits = min_dp_aux;
819 	if (min_dp_main > 0)
820 		sw->min_dp_main_credits = min_dp_main;
821 	if (max_pcie > 0)
822 		sw->max_pcie_credits = max_pcie;
823 	if (max_dma > 0)
824 		sw->max_dma_credits = max_dma;
825 
826 	return 0;
827 
828 err_invalid:
829 	return -EINVAL;
830 }
831 
832 /**
833  * usb4_switch_query_dp_resource() - Query availability of DP IN resource
834  * @sw: USB4 router
835  * @in: DP IN adapter
836  *
837  * For DP tunneling this function can be used to query availability of
838  * DP IN resource. Returns true if the resource is available for DP
839  * tunneling, false otherwise.
840  */
841 bool usb4_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in)
842 {
843 	u32 metadata = in->port;
844 	u8 status;
845 	int ret;
846 
847 	ret = usb4_switch_op(sw, USB4_SWITCH_OP_QUERY_DP_RESOURCE, &metadata,
848 			     &status);
849 	/*
850 	 * If DP resource allocation is not supported assume it is
851 	 * always available.
852 	 */
853 	if (ret == -EOPNOTSUPP)
854 		return true;
855 	if (ret)
856 		return false;
857 
858 	return !status;
859 }
860 
861 /**
862  * usb4_switch_alloc_dp_resource() - Allocate DP IN resource
863  * @sw: USB4 router
864  * @in: DP IN adapter
865  *
866  * Allocates DP IN resource for DP tunneling using USB4 router
867  * operations. If the resource was allocated returns %0. Otherwise
868  * returns negative errno, in particular %-EBUSY if the resource is
869  * already allocated.
870  */
871 int usb4_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
872 {
873 	u32 metadata = in->port;
874 	u8 status;
875 	int ret;
876 
877 	ret = usb4_switch_op(sw, USB4_SWITCH_OP_ALLOC_DP_RESOURCE, &metadata,
878 			     &status);
879 	if (ret == -EOPNOTSUPP)
880 		return 0;
881 	if (ret)
882 		return ret;
883 
884 	return status ? -EBUSY : 0;
885 }
886 
887 /**
888  * usb4_switch_dealloc_dp_resource() - Releases allocated DP IN resource
889  * @sw: USB4 router
890  * @in: DP IN adapter
891  *
892  * Releases the previously allocated DP IN resource.
893  */
894 int usb4_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in)
895 {
896 	u32 metadata = in->port;
897 	u8 status;
898 	int ret;
899 
900 	ret = usb4_switch_op(sw, USB4_SWITCH_OP_DEALLOC_DP_RESOURCE, &metadata,
901 			     &status);
902 	if (ret == -EOPNOTSUPP)
903 		return 0;
904 	if (ret)
905 		return ret;
906 
907 	return status ? -EIO : 0;
908 }
909 
910 static int usb4_port_idx(const struct tb_switch *sw, const struct tb_port *port)
911 {
912 	struct tb_port *p;
913 	int usb4_idx = 0;
914 
915 	/* Assume port is primary */
916 	tb_switch_for_each_port(sw, p) {
917 		if (!tb_port_is_null(p))
918 			continue;
919 		if (tb_is_upstream_port(p))
920 			continue;
921 		if (!p->link_nr) {
922 			if (p == port)
923 				break;
924 			usb4_idx++;
925 		}
926 	}
927 
928 	return usb4_idx;
929 }
930 
931 /**
932  * usb4_switch_map_pcie_down() - Map USB4 port to a PCIe downstream adapter
933  * @sw: USB4 router
934  * @port: USB4 port
935  *
936  * USB4 routers have direct mapping between USB4 ports and PCIe
937  * downstream adapters where the PCIe topology is extended. This
938  * function returns the corresponding downstream PCIe adapter or %NULL
939  * if no such mapping was possible.
940  */
941 struct tb_port *usb4_switch_map_pcie_down(struct tb_switch *sw,
942 					  const struct tb_port *port)
943 {
944 	int usb4_idx = usb4_port_idx(sw, port);
945 	struct tb_port *p;
946 	int pcie_idx = 0;
947 
948 	/* Find PCIe down port matching usb4_port */
949 	tb_switch_for_each_port(sw, p) {
950 		if (!tb_port_is_pcie_down(p))
951 			continue;
952 
953 		if (pcie_idx == usb4_idx)
954 			return p;
955 
956 		pcie_idx++;
957 	}
958 
959 	return NULL;
960 }
961 
962 /**
963  * usb4_switch_map_usb3_down() - Map USB4 port to a USB3 downstream adapter
964  * @sw: USB4 router
965  * @port: USB4 port
966  *
967  * USB4 routers have direct mapping between USB4 ports and USB 3.x
968  * downstream adapters where the USB 3.x topology is extended. This
969  * function returns the corresponding downstream USB 3.x adapter or
970  * %NULL if no such mapping was possible.
971  */
972 struct tb_port *usb4_switch_map_usb3_down(struct tb_switch *sw,
973 					  const struct tb_port *port)
974 {
975 	int usb4_idx = usb4_port_idx(sw, port);
976 	struct tb_port *p;
977 	int usb_idx = 0;
978 
979 	/* Find USB3 down port matching usb4_port */
980 	tb_switch_for_each_port(sw, p) {
981 		if (!tb_port_is_usb3_down(p))
982 			continue;
983 
984 		if (usb_idx == usb4_idx)
985 			return p;
986 
987 		usb_idx++;
988 	}
989 
990 	return NULL;
991 }
992 
993 /**
994  * usb4_switch_add_ports() - Add USB4 ports for this router
995  * @sw: USB4 router
996  *
997  * For USB4 router finds all USB4 ports and registers devices for each.
998  * Can be called to any router.
999  *
1000  * Return %0 in case of success and negative errno in case of failure.
1001  */
1002 int usb4_switch_add_ports(struct tb_switch *sw)
1003 {
1004 	struct tb_port *port;
1005 
1006 	if (tb_switch_is_icm(sw) || !tb_switch_is_usb4(sw))
1007 		return 0;
1008 
1009 	tb_switch_for_each_port(sw, port) {
1010 		struct usb4_port *usb4;
1011 
1012 		if (!tb_port_is_null(port))
1013 			continue;
1014 		if (!port->cap_usb4)
1015 			continue;
1016 
1017 		usb4 = usb4_port_device_add(port);
1018 		if (IS_ERR(usb4)) {
1019 			usb4_switch_remove_ports(sw);
1020 			return PTR_ERR(usb4);
1021 		}
1022 
1023 		port->usb4 = usb4;
1024 	}
1025 
1026 	return 0;
1027 }
1028 
1029 /**
1030  * usb4_switch_remove_ports() - Removes USB4 ports from this router
1031  * @sw: USB4 router
1032  *
1033  * Unregisters previously registered USB4 ports.
1034  */
1035 void usb4_switch_remove_ports(struct tb_switch *sw)
1036 {
1037 	struct tb_port *port;
1038 
1039 	tb_switch_for_each_port(sw, port) {
1040 		if (port->usb4) {
1041 			usb4_port_device_remove(port->usb4);
1042 			port->usb4 = NULL;
1043 		}
1044 	}
1045 }
1046 
1047 /**
1048  * usb4_port_unlock() - Unlock USB4 downstream port
1049  * @port: USB4 port to unlock
1050  *
1051  * Unlocks USB4 downstream port so that the connection manager can
1052  * access the router below this port.
1053  */
1054 int usb4_port_unlock(struct tb_port *port)
1055 {
1056 	int ret;
1057 	u32 val;
1058 
1059 	ret = tb_port_read(port, &val, TB_CFG_PORT, ADP_CS_4, 1);
1060 	if (ret)
1061 		return ret;
1062 
1063 	val &= ~ADP_CS_4_LCK;
1064 	return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_4, 1);
1065 }
1066 
1067 /**
1068  * usb4_port_hotplug_enable() - Enables hotplug for a port
1069  * @port: USB4 port to operate on
1070  *
1071  * Enables hot plug events on a given port. This is only intended
1072  * to be used on lane, DP-IN, and DP-OUT adapters.
1073  */
1074 int usb4_port_hotplug_enable(struct tb_port *port)
1075 {
1076 	int ret;
1077 	u32 val;
1078 
1079 	ret = tb_port_read(port, &val, TB_CFG_PORT, ADP_CS_5, 1);
1080 	if (ret)
1081 		return ret;
1082 
1083 	val &= ~ADP_CS_5_DHP;
1084 	return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_5, 1);
1085 }
1086 
1087 static int usb4_port_set_configured(struct tb_port *port, bool configured)
1088 {
1089 	int ret;
1090 	u32 val;
1091 
1092 	if (!port->cap_usb4)
1093 		return -EINVAL;
1094 
1095 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1096 			   port->cap_usb4 + PORT_CS_19, 1);
1097 	if (ret)
1098 		return ret;
1099 
1100 	if (configured)
1101 		val |= PORT_CS_19_PC;
1102 	else
1103 		val &= ~PORT_CS_19_PC;
1104 
1105 	return tb_port_write(port, &val, TB_CFG_PORT,
1106 			     port->cap_usb4 + PORT_CS_19, 1);
1107 }
1108 
1109 /**
1110  * usb4_port_configure() - Set USB4 port configured
1111  * @port: USB4 router
1112  *
1113  * Sets the USB4 link to be configured for power management purposes.
1114  */
1115 int usb4_port_configure(struct tb_port *port)
1116 {
1117 	return usb4_port_set_configured(port, true);
1118 }
1119 
1120 /**
1121  * usb4_port_unconfigure() - Set USB4 port unconfigured
1122  * @port: USB4 router
1123  *
1124  * Sets the USB4 link to be unconfigured for power management purposes.
1125  */
1126 void usb4_port_unconfigure(struct tb_port *port)
1127 {
1128 	usb4_port_set_configured(port, false);
1129 }
1130 
1131 static int usb4_set_xdomain_configured(struct tb_port *port, bool configured)
1132 {
1133 	int ret;
1134 	u32 val;
1135 
1136 	if (!port->cap_usb4)
1137 		return -EINVAL;
1138 
1139 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1140 			   port->cap_usb4 + PORT_CS_19, 1);
1141 	if (ret)
1142 		return ret;
1143 
1144 	if (configured)
1145 		val |= PORT_CS_19_PID;
1146 	else
1147 		val &= ~PORT_CS_19_PID;
1148 
1149 	return tb_port_write(port, &val, TB_CFG_PORT,
1150 			     port->cap_usb4 + PORT_CS_19, 1);
1151 }
1152 
1153 /**
1154  * usb4_port_configure_xdomain() - Configure port for XDomain
1155  * @port: USB4 port connected to another host
1156  * @xd: XDomain that is connected to the port
1157  *
1158  * Marks the USB4 port as being connected to another host and updates
1159  * the link type. Returns %0 in success and negative errno in failure.
1160  */
1161 int usb4_port_configure_xdomain(struct tb_port *port, struct tb_xdomain *xd)
1162 {
1163 	xd->link_usb4 = link_is_usb4(port);
1164 	return usb4_set_xdomain_configured(port, true);
1165 }
1166 
1167 /**
1168  * usb4_port_unconfigure_xdomain() - Unconfigure port for XDomain
1169  * @port: USB4 port that was connected to another host
1170  *
1171  * Clears USB4 port from being marked as XDomain.
1172  */
1173 void usb4_port_unconfigure_xdomain(struct tb_port *port)
1174 {
1175 	usb4_set_xdomain_configured(port, false);
1176 }
1177 
1178 static int usb4_port_wait_for_bit(struct tb_port *port, u32 offset, u32 bit,
1179 				  u32 value, int timeout_msec)
1180 {
1181 	ktime_t timeout = ktime_add_ms(ktime_get(), timeout_msec);
1182 
1183 	do {
1184 		u32 val;
1185 		int ret;
1186 
1187 		ret = tb_port_read(port, &val, TB_CFG_PORT, offset, 1);
1188 		if (ret)
1189 			return ret;
1190 
1191 		if ((val & bit) == value)
1192 			return 0;
1193 
1194 		usleep_range(50, 100);
1195 	} while (ktime_before(ktime_get(), timeout));
1196 
1197 	return -ETIMEDOUT;
1198 }
1199 
1200 static int usb4_port_read_data(struct tb_port *port, void *data, size_t dwords)
1201 {
1202 	if (dwords > NVM_DATA_DWORDS)
1203 		return -EINVAL;
1204 
1205 	return tb_port_read(port, data, TB_CFG_PORT, port->cap_usb4 + PORT_CS_2,
1206 			    dwords);
1207 }
1208 
1209 static int usb4_port_write_data(struct tb_port *port, const void *data,
1210 				size_t dwords)
1211 {
1212 	if (dwords > NVM_DATA_DWORDS)
1213 		return -EINVAL;
1214 
1215 	return tb_port_write(port, data, TB_CFG_PORT, port->cap_usb4 + PORT_CS_2,
1216 			     dwords);
1217 }
1218 
1219 static int usb4_port_sb_read(struct tb_port *port, enum usb4_sb_target target,
1220 			     u8 index, u8 reg, void *buf, u8 size)
1221 {
1222 	size_t dwords = DIV_ROUND_UP(size, 4);
1223 	int ret;
1224 	u32 val;
1225 
1226 	if (!port->cap_usb4)
1227 		return -EINVAL;
1228 
1229 	val = reg;
1230 	val |= size << PORT_CS_1_LENGTH_SHIFT;
1231 	val |= (target << PORT_CS_1_TARGET_SHIFT) & PORT_CS_1_TARGET_MASK;
1232 	if (target == USB4_SB_TARGET_RETIMER)
1233 		val |= (index << PORT_CS_1_RETIMER_INDEX_SHIFT);
1234 	val |= PORT_CS_1_PND;
1235 
1236 	ret = tb_port_write(port, &val, TB_CFG_PORT,
1237 			    port->cap_usb4 + PORT_CS_1, 1);
1238 	if (ret)
1239 		return ret;
1240 
1241 	ret = usb4_port_wait_for_bit(port, port->cap_usb4 + PORT_CS_1,
1242 				     PORT_CS_1_PND, 0, 500);
1243 	if (ret)
1244 		return ret;
1245 
1246 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1247 			    port->cap_usb4 + PORT_CS_1, 1);
1248 	if (ret)
1249 		return ret;
1250 
1251 	if (val & PORT_CS_1_NR)
1252 		return -ENODEV;
1253 	if (val & PORT_CS_1_RC)
1254 		return -EIO;
1255 
1256 	return buf ? usb4_port_read_data(port, buf, dwords) : 0;
1257 }
1258 
1259 static int usb4_port_sb_write(struct tb_port *port, enum usb4_sb_target target,
1260 			      u8 index, u8 reg, const void *buf, u8 size)
1261 {
1262 	size_t dwords = DIV_ROUND_UP(size, 4);
1263 	int ret;
1264 	u32 val;
1265 
1266 	if (!port->cap_usb4)
1267 		return -EINVAL;
1268 
1269 	if (buf) {
1270 		ret = usb4_port_write_data(port, buf, dwords);
1271 		if (ret)
1272 			return ret;
1273 	}
1274 
1275 	val = reg;
1276 	val |= size << PORT_CS_1_LENGTH_SHIFT;
1277 	val |= PORT_CS_1_WNR_WRITE;
1278 	val |= (target << PORT_CS_1_TARGET_SHIFT) & PORT_CS_1_TARGET_MASK;
1279 	if (target == USB4_SB_TARGET_RETIMER)
1280 		val |= (index << PORT_CS_1_RETIMER_INDEX_SHIFT);
1281 	val |= PORT_CS_1_PND;
1282 
1283 	ret = tb_port_write(port, &val, TB_CFG_PORT,
1284 			    port->cap_usb4 + PORT_CS_1, 1);
1285 	if (ret)
1286 		return ret;
1287 
1288 	ret = usb4_port_wait_for_bit(port, port->cap_usb4 + PORT_CS_1,
1289 				     PORT_CS_1_PND, 0, 500);
1290 	if (ret)
1291 		return ret;
1292 
1293 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1294 			    port->cap_usb4 + PORT_CS_1, 1);
1295 	if (ret)
1296 		return ret;
1297 
1298 	if (val & PORT_CS_1_NR)
1299 		return -ENODEV;
1300 	if (val & PORT_CS_1_RC)
1301 		return -EIO;
1302 
1303 	return 0;
1304 }
1305 
1306 static int usb4_port_sb_opcode_err_to_errno(u32 val)
1307 {
1308 	switch (val) {
1309 	case 0:
1310 		return 0;
1311 	case USB4_SB_OPCODE_ERR:
1312 		return -EAGAIN;
1313 	case USB4_SB_OPCODE_ONS:
1314 		return -EOPNOTSUPP;
1315 	default:
1316 		return -EIO;
1317 	}
1318 }
1319 
1320 static int usb4_port_sb_op(struct tb_port *port, enum usb4_sb_target target,
1321 			   u8 index, enum usb4_sb_opcode opcode, int timeout_msec)
1322 {
1323 	ktime_t timeout;
1324 	u32 val;
1325 	int ret;
1326 
1327 	val = opcode;
1328 	ret = usb4_port_sb_write(port, target, index, USB4_SB_OPCODE, &val,
1329 				 sizeof(val));
1330 	if (ret)
1331 		return ret;
1332 
1333 	timeout = ktime_add_ms(ktime_get(), timeout_msec);
1334 
1335 	do {
1336 		/* Check results */
1337 		ret = usb4_port_sb_read(port, target, index, USB4_SB_OPCODE,
1338 					&val, sizeof(val));
1339 		if (ret)
1340 			return ret;
1341 
1342 		if (val != opcode)
1343 			return usb4_port_sb_opcode_err_to_errno(val);
1344 	} while (ktime_before(ktime_get(), timeout));
1345 
1346 	return -ETIMEDOUT;
1347 }
1348 
1349 static int usb4_port_set_router_offline(struct tb_port *port, bool offline)
1350 {
1351 	u32 val = !offline;
1352 	int ret;
1353 
1354 	ret = usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0,
1355 				  USB4_SB_METADATA, &val, sizeof(val));
1356 	if (ret)
1357 		return ret;
1358 
1359 	val = USB4_SB_OPCODE_ROUTER_OFFLINE;
1360 	return usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0,
1361 				  USB4_SB_OPCODE, &val, sizeof(val));
1362 }
1363 
1364 /**
1365  * usb4_port_router_offline() - Put the USB4 port to offline mode
1366  * @port: USB4 port
1367  *
1368  * This function puts the USB4 port into offline mode. In this mode the
1369  * port does not react on hotplug events anymore. This needs to be
1370  * called before retimer access is done when the USB4 links is not up.
1371  *
1372  * Returns %0 in case of success and negative errno if there was an
1373  * error.
1374  */
1375 int usb4_port_router_offline(struct tb_port *port)
1376 {
1377 	return usb4_port_set_router_offline(port, true);
1378 }
1379 
1380 /**
1381  * usb4_port_router_online() - Put the USB4 port back to online
1382  * @port: USB4 port
1383  *
1384  * Makes the USB4 port functional again.
1385  */
1386 int usb4_port_router_online(struct tb_port *port)
1387 {
1388 	return usb4_port_set_router_offline(port, false);
1389 }
1390 
1391 /**
1392  * usb4_port_enumerate_retimers() - Send RT broadcast transaction
1393  * @port: USB4 port
1394  *
1395  * This forces the USB4 port to send broadcast RT transaction which
1396  * makes the retimers on the link to assign index to themselves. Returns
1397  * %0 in case of success and negative errno if there was an error.
1398  */
1399 int usb4_port_enumerate_retimers(struct tb_port *port)
1400 {
1401 	u32 val;
1402 
1403 	val = USB4_SB_OPCODE_ENUMERATE_RETIMERS;
1404 	return usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0,
1405 				  USB4_SB_OPCODE, &val, sizeof(val));
1406 }
1407 
1408 /**
1409  * usb4_port_clx_supported() - Check if CLx is supported by the link
1410  * @port: Port to check for CLx support for
1411  *
1412  * PORT_CS_18_CPS bit reflects if the link supports CLx including
1413  * active cables (if connected on the link).
1414  */
1415 bool usb4_port_clx_supported(struct tb_port *port)
1416 {
1417 	int ret;
1418 	u32 val;
1419 
1420 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1421 			   port->cap_usb4 + PORT_CS_18, 1);
1422 	if (ret)
1423 		return false;
1424 
1425 	return !!(val & PORT_CS_18_CPS);
1426 }
1427 
1428 /**
1429  * usb4_port_margining_caps() - Read USB4 port marginig capabilities
1430  * @port: USB4 port
1431  * @caps: Array with at least two elements to hold the results
1432  *
1433  * Reads the USB4 port lane margining capabilities into @caps.
1434  */
1435 int usb4_port_margining_caps(struct tb_port *port, u32 *caps)
1436 {
1437 	int ret;
1438 
1439 	ret = usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0,
1440 			      USB4_SB_OPCODE_READ_LANE_MARGINING_CAP, 500);
1441 	if (ret)
1442 		return ret;
1443 
1444 	return usb4_port_sb_read(port, USB4_SB_TARGET_ROUTER, 0,
1445 				 USB4_SB_DATA, caps, sizeof(*caps) * 2);
1446 }
1447 
1448 /**
1449  * usb4_port_hw_margin() - Run hardware lane margining on port
1450  * @port: USB4 port
1451  * @lanes: Which lanes to run (must match the port capabilities). Can be
1452  *	   %0, %1 or %7.
1453  * @ber_level: BER level contour value
1454  * @timing: Perform timing margining instead of voltage
1455  * @right_high: Use Right/high margin instead of left/low
1456  * @results: Array with at least two elements to hold the results
1457  *
1458  * Runs hardware lane margining on USB4 port and returns the result in
1459  * @results.
1460  */
1461 int usb4_port_hw_margin(struct tb_port *port, unsigned int lanes,
1462 			unsigned int ber_level, bool timing, bool right_high,
1463 			u32 *results)
1464 {
1465 	u32 val;
1466 	int ret;
1467 
1468 	val = lanes;
1469 	if (timing)
1470 		val |= USB4_MARGIN_HW_TIME;
1471 	if (right_high)
1472 		val |= USB4_MARGIN_HW_RH;
1473 	if (ber_level)
1474 		val |= (ber_level << USB4_MARGIN_HW_BER_SHIFT) &
1475 			USB4_MARGIN_HW_BER_MASK;
1476 
1477 	ret = usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0,
1478 				 USB4_SB_METADATA, &val, sizeof(val));
1479 	if (ret)
1480 		return ret;
1481 
1482 	ret = usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0,
1483 			      USB4_SB_OPCODE_RUN_HW_LANE_MARGINING, 2500);
1484 	if (ret)
1485 		return ret;
1486 
1487 	return usb4_port_sb_read(port, USB4_SB_TARGET_ROUTER, 0,
1488 				 USB4_SB_DATA, results, sizeof(*results) * 2);
1489 }
1490 
1491 /**
1492  * usb4_port_sw_margin() - Run software lane margining on port
1493  * @port: USB4 port
1494  * @lanes: Which lanes to run (must match the port capabilities). Can be
1495  *	   %0, %1 or %7.
1496  * @timing: Perform timing margining instead of voltage
1497  * @right_high: Use Right/high margin instead of left/low
1498  * @counter: What to do with the error counter
1499  *
1500  * Runs software lane margining on USB4 port. Read back the error
1501  * counters by calling usb4_port_sw_margin_errors(). Returns %0 in
1502  * success and negative errno otherwise.
1503  */
1504 int usb4_port_sw_margin(struct tb_port *port, unsigned int lanes, bool timing,
1505 			bool right_high, u32 counter)
1506 {
1507 	u32 val;
1508 	int ret;
1509 
1510 	val = lanes;
1511 	if (timing)
1512 		val |= USB4_MARGIN_SW_TIME;
1513 	if (right_high)
1514 		val |= USB4_MARGIN_SW_RH;
1515 	val |= (counter << USB4_MARGIN_SW_COUNTER_SHIFT) &
1516 		USB4_MARGIN_SW_COUNTER_MASK;
1517 
1518 	ret = usb4_port_sb_write(port, USB4_SB_TARGET_ROUTER, 0,
1519 				 USB4_SB_METADATA, &val, sizeof(val));
1520 	if (ret)
1521 		return ret;
1522 
1523 	return usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0,
1524 			       USB4_SB_OPCODE_RUN_SW_LANE_MARGINING, 2500);
1525 }
1526 
1527 /**
1528  * usb4_port_sw_margin_errors() - Read the software margining error counters
1529  * @port: USB4 port
1530  * @errors: Error metadata is copied here.
1531  *
1532  * This reads back the software margining error counters from the port.
1533  * Returns %0 in success and negative errno otherwise.
1534  */
1535 int usb4_port_sw_margin_errors(struct tb_port *port, u32 *errors)
1536 {
1537 	int ret;
1538 
1539 	ret = usb4_port_sb_op(port, USB4_SB_TARGET_ROUTER, 0,
1540 			      USB4_SB_OPCODE_READ_SW_MARGIN_ERR, 150);
1541 	if (ret)
1542 		return ret;
1543 
1544 	return usb4_port_sb_read(port, USB4_SB_TARGET_ROUTER, 0,
1545 				 USB4_SB_METADATA, errors, sizeof(*errors));
1546 }
1547 
1548 static inline int usb4_port_retimer_op(struct tb_port *port, u8 index,
1549 				       enum usb4_sb_opcode opcode,
1550 				       int timeout_msec)
1551 {
1552 	return usb4_port_sb_op(port, USB4_SB_TARGET_RETIMER, index, opcode,
1553 			       timeout_msec);
1554 }
1555 
1556 /**
1557  * usb4_port_retimer_set_inbound_sbtx() - Enable sideband channel transactions
1558  * @port: USB4 port
1559  * @index: Retimer index
1560  *
1561  * Enables sideband channel transations on SBTX. Can be used when USB4
1562  * link does not go up, for example if there is no device connected.
1563  */
1564 int usb4_port_retimer_set_inbound_sbtx(struct tb_port *port, u8 index)
1565 {
1566 	int ret;
1567 
1568 	ret = usb4_port_retimer_op(port, index, USB4_SB_OPCODE_SET_INBOUND_SBTX,
1569 				   500);
1570 
1571 	if (ret != -ENODEV)
1572 		return ret;
1573 
1574 	/*
1575 	 * Per the USB4 retimer spec, the retimer is not required to
1576 	 * send an RT (Retimer Transaction) response for the first
1577 	 * SET_INBOUND_SBTX command
1578 	 */
1579 	return usb4_port_retimer_op(port, index, USB4_SB_OPCODE_SET_INBOUND_SBTX,
1580 				    500);
1581 }
1582 
1583 /**
1584  * usb4_port_retimer_unset_inbound_sbtx() - Disable sideband channel transactions
1585  * @port: USB4 port
1586  * @index: Retimer index
1587  *
1588  * Disables sideband channel transations on SBTX. The reverse of
1589  * usb4_port_retimer_set_inbound_sbtx().
1590  */
1591 int usb4_port_retimer_unset_inbound_sbtx(struct tb_port *port, u8 index)
1592 {
1593 	return usb4_port_retimer_op(port, index,
1594 				    USB4_SB_OPCODE_UNSET_INBOUND_SBTX, 500);
1595 }
1596 
1597 /**
1598  * usb4_port_retimer_read() - Read from retimer sideband registers
1599  * @port: USB4 port
1600  * @index: Retimer index
1601  * @reg: Sideband register to read
1602  * @buf: Data from @reg is stored here
1603  * @size: Number of bytes to read
1604  *
1605  * Function reads retimer sideband registers starting from @reg. The
1606  * retimer is connected to @port at @index. Returns %0 in case of
1607  * success, and read data is copied to @buf. If there is no retimer
1608  * present at given @index returns %-ENODEV. In any other failure
1609  * returns negative errno.
1610  */
1611 int usb4_port_retimer_read(struct tb_port *port, u8 index, u8 reg, void *buf,
1612 			   u8 size)
1613 {
1614 	return usb4_port_sb_read(port, USB4_SB_TARGET_RETIMER, index, reg, buf,
1615 				 size);
1616 }
1617 
1618 /**
1619  * usb4_port_retimer_write() - Write to retimer sideband registers
1620  * @port: USB4 port
1621  * @index: Retimer index
1622  * @reg: Sideband register to write
1623  * @buf: Data that is written starting from @reg
1624  * @size: Number of bytes to write
1625  *
1626  * Writes retimer sideband registers starting from @reg. The retimer is
1627  * connected to @port at @index. Returns %0 in case of success. If there
1628  * is no retimer present at given @index returns %-ENODEV. In any other
1629  * failure returns negative errno.
1630  */
1631 int usb4_port_retimer_write(struct tb_port *port, u8 index, u8 reg,
1632 			    const void *buf, u8 size)
1633 {
1634 	return usb4_port_sb_write(port, USB4_SB_TARGET_RETIMER, index, reg, buf,
1635 				  size);
1636 }
1637 
1638 /**
1639  * usb4_port_retimer_is_last() - Is the retimer last on-board retimer
1640  * @port: USB4 port
1641  * @index: Retimer index
1642  *
1643  * If the retimer at @index is last one (connected directly to the
1644  * Type-C port) this function returns %1. If it is not returns %0. If
1645  * the retimer is not present returns %-ENODEV. Otherwise returns
1646  * negative errno.
1647  */
1648 int usb4_port_retimer_is_last(struct tb_port *port, u8 index)
1649 {
1650 	u32 metadata;
1651 	int ret;
1652 
1653 	ret = usb4_port_retimer_op(port, index, USB4_SB_OPCODE_QUERY_LAST_RETIMER,
1654 				   500);
1655 	if (ret)
1656 		return ret;
1657 
1658 	ret = usb4_port_retimer_read(port, index, USB4_SB_METADATA, &metadata,
1659 				     sizeof(metadata));
1660 	return ret ? ret : metadata & 1;
1661 }
1662 
1663 /**
1664  * usb4_port_retimer_nvm_sector_size() - Read retimer NVM sector size
1665  * @port: USB4 port
1666  * @index: Retimer index
1667  *
1668  * Reads NVM sector size (in bytes) of a retimer at @index. This
1669  * operation can be used to determine whether the retimer supports NVM
1670  * upgrade for example. Returns sector size in bytes or negative errno
1671  * in case of error. Specifically returns %-ENODEV if there is no
1672  * retimer at @index.
1673  */
1674 int usb4_port_retimer_nvm_sector_size(struct tb_port *port, u8 index)
1675 {
1676 	u32 metadata;
1677 	int ret;
1678 
1679 	ret = usb4_port_retimer_op(port, index, USB4_SB_OPCODE_GET_NVM_SECTOR_SIZE,
1680 				   500);
1681 	if (ret)
1682 		return ret;
1683 
1684 	ret = usb4_port_retimer_read(port, index, USB4_SB_METADATA, &metadata,
1685 				     sizeof(metadata));
1686 	return ret ? ret : metadata & USB4_NVM_SECTOR_SIZE_MASK;
1687 }
1688 
1689 /**
1690  * usb4_port_retimer_nvm_set_offset() - Set NVM write offset
1691  * @port: USB4 port
1692  * @index: Retimer index
1693  * @address: Start offset
1694  *
1695  * Exlicitly sets NVM write offset. Normally when writing to NVM this is
1696  * done automatically by usb4_port_retimer_nvm_write().
1697  *
1698  * Returns %0 in success and negative errno if there was a failure.
1699  */
1700 int usb4_port_retimer_nvm_set_offset(struct tb_port *port, u8 index,
1701 				     unsigned int address)
1702 {
1703 	u32 metadata, dwaddress;
1704 	int ret;
1705 
1706 	dwaddress = address / 4;
1707 	metadata = (dwaddress << USB4_NVM_SET_OFFSET_SHIFT) &
1708 		  USB4_NVM_SET_OFFSET_MASK;
1709 
1710 	ret = usb4_port_retimer_write(port, index, USB4_SB_METADATA, &metadata,
1711 				      sizeof(metadata));
1712 	if (ret)
1713 		return ret;
1714 
1715 	return usb4_port_retimer_op(port, index, USB4_SB_OPCODE_NVM_SET_OFFSET,
1716 				    500);
1717 }
1718 
1719 struct retimer_info {
1720 	struct tb_port *port;
1721 	u8 index;
1722 };
1723 
1724 static int usb4_port_retimer_nvm_write_next_block(void *data,
1725 	unsigned int dwaddress, const void *buf, size_t dwords)
1726 
1727 {
1728 	const struct retimer_info *info = data;
1729 	struct tb_port *port = info->port;
1730 	u8 index = info->index;
1731 	int ret;
1732 
1733 	ret = usb4_port_retimer_write(port, index, USB4_SB_DATA,
1734 				      buf, dwords * 4);
1735 	if (ret)
1736 		return ret;
1737 
1738 	return usb4_port_retimer_op(port, index,
1739 			USB4_SB_OPCODE_NVM_BLOCK_WRITE, 1000);
1740 }
1741 
1742 /**
1743  * usb4_port_retimer_nvm_write() - Write to retimer NVM
1744  * @port: USB4 port
1745  * @index: Retimer index
1746  * @address: Byte address where to start the write
1747  * @buf: Data to write
1748  * @size: Size in bytes how much to write
1749  *
1750  * Writes @size bytes from @buf to the retimer NVM. Used for NVM
1751  * upgrade. Returns %0 if the data was written successfully and negative
1752  * errno in case of failure. Specifically returns %-ENODEV if there is
1753  * no retimer at @index.
1754  */
1755 int usb4_port_retimer_nvm_write(struct tb_port *port, u8 index, unsigned int address,
1756 				const void *buf, size_t size)
1757 {
1758 	struct retimer_info info = { .port = port, .index = index };
1759 	int ret;
1760 
1761 	ret = usb4_port_retimer_nvm_set_offset(port, index, address);
1762 	if (ret)
1763 		return ret;
1764 
1765 	return tb_nvm_write_data(address, buf, size, USB4_DATA_RETRIES,
1766 				 usb4_port_retimer_nvm_write_next_block, &info);
1767 }
1768 
1769 /**
1770  * usb4_port_retimer_nvm_authenticate() - Start retimer NVM upgrade
1771  * @port: USB4 port
1772  * @index: Retimer index
1773  *
1774  * After the new NVM image has been written via usb4_port_retimer_nvm_write()
1775  * this function can be used to trigger the NVM upgrade process. If
1776  * successful the retimer restarts with the new NVM and may not have the
1777  * index set so one needs to call usb4_port_enumerate_retimers() to
1778  * force index to be assigned.
1779  */
1780 int usb4_port_retimer_nvm_authenticate(struct tb_port *port, u8 index)
1781 {
1782 	u32 val;
1783 
1784 	/*
1785 	 * We need to use the raw operation here because once the
1786 	 * authentication completes the retimer index is not set anymore
1787 	 * so we do not get back the status now.
1788 	 */
1789 	val = USB4_SB_OPCODE_NVM_AUTH_WRITE;
1790 	return usb4_port_sb_write(port, USB4_SB_TARGET_RETIMER, index,
1791 				  USB4_SB_OPCODE, &val, sizeof(val));
1792 }
1793 
1794 /**
1795  * usb4_port_retimer_nvm_authenticate_status() - Read status of NVM upgrade
1796  * @port: USB4 port
1797  * @index: Retimer index
1798  * @status: Raw status code read from metadata
1799  *
1800  * This can be called after usb4_port_retimer_nvm_authenticate() and
1801  * usb4_port_enumerate_retimers() to fetch status of the NVM upgrade.
1802  *
1803  * Returns %0 if the authentication status was successfully read. The
1804  * completion metadata (the result) is then stored into @status. If
1805  * reading the status fails, returns negative errno.
1806  */
1807 int usb4_port_retimer_nvm_authenticate_status(struct tb_port *port, u8 index,
1808 					      u32 *status)
1809 {
1810 	u32 metadata, val;
1811 	int ret;
1812 
1813 	ret = usb4_port_retimer_read(port, index, USB4_SB_OPCODE, &val,
1814 				     sizeof(val));
1815 	if (ret)
1816 		return ret;
1817 
1818 	ret = usb4_port_sb_opcode_err_to_errno(val);
1819 	switch (ret) {
1820 	case 0:
1821 		*status = 0;
1822 		return 0;
1823 
1824 	case -EAGAIN:
1825 		ret = usb4_port_retimer_read(port, index, USB4_SB_METADATA,
1826 					     &metadata, sizeof(metadata));
1827 		if (ret)
1828 			return ret;
1829 
1830 		*status = metadata & USB4_SB_METADATA_NVM_AUTH_WRITE_MASK;
1831 		return 0;
1832 
1833 	default:
1834 		return ret;
1835 	}
1836 }
1837 
1838 static int usb4_port_retimer_nvm_read_block(void *data, unsigned int dwaddress,
1839 					    void *buf, size_t dwords)
1840 {
1841 	const struct retimer_info *info = data;
1842 	struct tb_port *port = info->port;
1843 	u8 index = info->index;
1844 	u32 metadata;
1845 	int ret;
1846 
1847 	metadata = dwaddress << USB4_NVM_READ_OFFSET_SHIFT;
1848 	if (dwords < NVM_DATA_DWORDS)
1849 		metadata |= dwords << USB4_NVM_READ_LENGTH_SHIFT;
1850 
1851 	ret = usb4_port_retimer_write(port, index, USB4_SB_METADATA, &metadata,
1852 				      sizeof(metadata));
1853 	if (ret)
1854 		return ret;
1855 
1856 	ret = usb4_port_retimer_op(port, index, USB4_SB_OPCODE_NVM_READ, 500);
1857 	if (ret)
1858 		return ret;
1859 
1860 	return usb4_port_retimer_read(port, index, USB4_SB_DATA, buf,
1861 				      dwords * 4);
1862 }
1863 
1864 /**
1865  * usb4_port_retimer_nvm_read() - Read contents of retimer NVM
1866  * @port: USB4 port
1867  * @index: Retimer index
1868  * @address: NVM address (in bytes) to start reading
1869  * @buf: Data read from NVM is stored here
1870  * @size: Number of bytes to read
1871  *
1872  * Reads retimer NVM and copies the contents to @buf. Returns %0 if the
1873  * read was successful and negative errno in case of failure.
1874  * Specifically returns %-ENODEV if there is no retimer at @index.
1875  */
1876 int usb4_port_retimer_nvm_read(struct tb_port *port, u8 index,
1877 			       unsigned int address, void *buf, size_t size)
1878 {
1879 	struct retimer_info info = { .port = port, .index = index };
1880 
1881 	return tb_nvm_read_data(address, buf, size, USB4_DATA_RETRIES,
1882 				usb4_port_retimer_nvm_read_block, &info);
1883 }
1884 
1885 static inline unsigned int
1886 usb4_usb3_port_max_bandwidth(const struct tb_port *port, unsigned int bw)
1887 {
1888 	/* Take the possible bandwidth limitation into account */
1889 	if (port->max_bw)
1890 		return min(bw, port->max_bw);
1891 	return bw;
1892 }
1893 
1894 /**
1895  * usb4_usb3_port_max_link_rate() - Maximum support USB3 link rate
1896  * @port: USB3 adapter port
1897  *
1898  * Return maximum supported link rate of a USB3 adapter in Mb/s.
1899  * Negative errno in case of error.
1900  */
1901 int usb4_usb3_port_max_link_rate(struct tb_port *port)
1902 {
1903 	int ret, lr;
1904 	u32 val;
1905 
1906 	if (!tb_port_is_usb3_down(port) && !tb_port_is_usb3_up(port))
1907 		return -EINVAL;
1908 
1909 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1910 			   port->cap_adap + ADP_USB3_CS_4, 1);
1911 	if (ret)
1912 		return ret;
1913 
1914 	lr = (val & ADP_USB3_CS_4_MSLR_MASK) >> ADP_USB3_CS_4_MSLR_SHIFT;
1915 	ret = lr == ADP_USB3_CS_4_MSLR_20G ? 20000 : 10000;
1916 
1917 	return usb4_usb3_port_max_bandwidth(port, ret);
1918 }
1919 
1920 /**
1921  * usb4_usb3_port_actual_link_rate() - Established USB3 link rate
1922  * @port: USB3 adapter port
1923  *
1924  * Return actual established link rate of a USB3 adapter in Mb/s. If the
1925  * link is not up returns %0 and negative errno in case of failure.
1926  */
1927 int usb4_usb3_port_actual_link_rate(struct tb_port *port)
1928 {
1929 	int ret, lr;
1930 	u32 val;
1931 
1932 	if (!tb_port_is_usb3_down(port) && !tb_port_is_usb3_up(port))
1933 		return -EINVAL;
1934 
1935 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1936 			   port->cap_adap + ADP_USB3_CS_4, 1);
1937 	if (ret)
1938 		return ret;
1939 
1940 	if (!(val & ADP_USB3_CS_4_ULV))
1941 		return 0;
1942 
1943 	lr = val & ADP_USB3_CS_4_ALR_MASK;
1944 	ret = lr == ADP_USB3_CS_4_ALR_20G ? 20000 : 10000;
1945 
1946 	return usb4_usb3_port_max_bandwidth(port, ret);
1947 }
1948 
1949 static int usb4_usb3_port_cm_request(struct tb_port *port, bool request)
1950 {
1951 	int ret;
1952 	u32 val;
1953 
1954 	if (!tb_port_is_usb3_down(port))
1955 		return -EINVAL;
1956 	if (tb_route(port->sw))
1957 		return -EINVAL;
1958 
1959 	ret = tb_port_read(port, &val, TB_CFG_PORT,
1960 			   port->cap_adap + ADP_USB3_CS_2, 1);
1961 	if (ret)
1962 		return ret;
1963 
1964 	if (request)
1965 		val |= ADP_USB3_CS_2_CMR;
1966 	else
1967 		val &= ~ADP_USB3_CS_2_CMR;
1968 
1969 	ret = tb_port_write(port, &val, TB_CFG_PORT,
1970 			    port->cap_adap + ADP_USB3_CS_2, 1);
1971 	if (ret)
1972 		return ret;
1973 
1974 	/*
1975 	 * We can use val here directly as the CMR bit is in the same place
1976 	 * as HCA. Just mask out others.
1977 	 */
1978 	val &= ADP_USB3_CS_2_CMR;
1979 	return usb4_port_wait_for_bit(port, port->cap_adap + ADP_USB3_CS_1,
1980 				      ADP_USB3_CS_1_HCA, val, 1500);
1981 }
1982 
1983 static inline int usb4_usb3_port_set_cm_request(struct tb_port *port)
1984 {
1985 	return usb4_usb3_port_cm_request(port, true);
1986 }
1987 
1988 static inline int usb4_usb3_port_clear_cm_request(struct tb_port *port)
1989 {
1990 	return usb4_usb3_port_cm_request(port, false);
1991 }
1992 
1993 static unsigned int usb3_bw_to_mbps(u32 bw, u8 scale)
1994 {
1995 	unsigned long uframes;
1996 
1997 	uframes = bw * 512UL << scale;
1998 	return DIV_ROUND_CLOSEST(uframes * 8000, MEGA);
1999 }
2000 
2001 static u32 mbps_to_usb3_bw(unsigned int mbps, u8 scale)
2002 {
2003 	unsigned long uframes;
2004 
2005 	/* 1 uframe is 1/8 ms (125 us) -> 1 / 8000 s */
2006 	uframes = ((unsigned long)mbps * MEGA) / 8000;
2007 	return DIV_ROUND_UP(uframes, 512UL << scale);
2008 }
2009 
2010 static int usb4_usb3_port_read_allocated_bandwidth(struct tb_port *port,
2011 						   int *upstream_bw,
2012 						   int *downstream_bw)
2013 {
2014 	u32 val, bw, scale;
2015 	int ret;
2016 
2017 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2018 			   port->cap_adap + ADP_USB3_CS_2, 1);
2019 	if (ret)
2020 		return ret;
2021 
2022 	ret = tb_port_read(port, &scale, TB_CFG_PORT,
2023 			   port->cap_adap + ADP_USB3_CS_3, 1);
2024 	if (ret)
2025 		return ret;
2026 
2027 	scale &= ADP_USB3_CS_3_SCALE_MASK;
2028 
2029 	bw = val & ADP_USB3_CS_2_AUBW_MASK;
2030 	*upstream_bw = usb3_bw_to_mbps(bw, scale);
2031 
2032 	bw = (val & ADP_USB3_CS_2_ADBW_MASK) >> ADP_USB3_CS_2_ADBW_SHIFT;
2033 	*downstream_bw = usb3_bw_to_mbps(bw, scale);
2034 
2035 	return 0;
2036 }
2037 
2038 /**
2039  * usb4_usb3_port_allocated_bandwidth() - Bandwidth allocated for USB3
2040  * @port: USB3 adapter port
2041  * @upstream_bw: Allocated upstream bandwidth is stored here
2042  * @downstream_bw: Allocated downstream bandwidth is stored here
2043  *
2044  * Stores currently allocated USB3 bandwidth into @upstream_bw and
2045  * @downstream_bw in Mb/s. Returns %0 in case of success and negative
2046  * errno in failure.
2047  */
2048 int usb4_usb3_port_allocated_bandwidth(struct tb_port *port, int *upstream_bw,
2049 				       int *downstream_bw)
2050 {
2051 	int ret;
2052 
2053 	ret = usb4_usb3_port_set_cm_request(port);
2054 	if (ret)
2055 		return ret;
2056 
2057 	ret = usb4_usb3_port_read_allocated_bandwidth(port, upstream_bw,
2058 						      downstream_bw);
2059 	usb4_usb3_port_clear_cm_request(port);
2060 
2061 	return ret;
2062 }
2063 
2064 static int usb4_usb3_port_read_consumed_bandwidth(struct tb_port *port,
2065 						  int *upstream_bw,
2066 						  int *downstream_bw)
2067 {
2068 	u32 val, bw, scale;
2069 	int ret;
2070 
2071 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2072 			   port->cap_adap + ADP_USB3_CS_1, 1);
2073 	if (ret)
2074 		return ret;
2075 
2076 	ret = tb_port_read(port, &scale, TB_CFG_PORT,
2077 			   port->cap_adap + ADP_USB3_CS_3, 1);
2078 	if (ret)
2079 		return ret;
2080 
2081 	scale &= ADP_USB3_CS_3_SCALE_MASK;
2082 
2083 	bw = val & ADP_USB3_CS_1_CUBW_MASK;
2084 	*upstream_bw = usb3_bw_to_mbps(bw, scale);
2085 
2086 	bw = (val & ADP_USB3_CS_1_CDBW_MASK) >> ADP_USB3_CS_1_CDBW_SHIFT;
2087 	*downstream_bw = usb3_bw_to_mbps(bw, scale);
2088 
2089 	return 0;
2090 }
2091 
2092 static int usb4_usb3_port_write_allocated_bandwidth(struct tb_port *port,
2093 						    int upstream_bw,
2094 						    int downstream_bw)
2095 {
2096 	u32 val, ubw, dbw, scale;
2097 	int ret, max_bw;
2098 
2099 	/* Figure out suitable scale */
2100 	scale = 0;
2101 	max_bw = max(upstream_bw, downstream_bw);
2102 	while (scale < 64) {
2103 		if (mbps_to_usb3_bw(max_bw, scale) < 4096)
2104 			break;
2105 		scale++;
2106 	}
2107 
2108 	if (WARN_ON(scale >= 64))
2109 		return -EINVAL;
2110 
2111 	ret = tb_port_write(port, &scale, TB_CFG_PORT,
2112 			    port->cap_adap + ADP_USB3_CS_3, 1);
2113 	if (ret)
2114 		return ret;
2115 
2116 	ubw = mbps_to_usb3_bw(upstream_bw, scale);
2117 	dbw = mbps_to_usb3_bw(downstream_bw, scale);
2118 
2119 	tb_port_dbg(port, "scaled bandwidth %u/%u, scale %u\n", ubw, dbw, scale);
2120 
2121 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2122 			   port->cap_adap + ADP_USB3_CS_2, 1);
2123 	if (ret)
2124 		return ret;
2125 
2126 	val &= ~(ADP_USB3_CS_2_AUBW_MASK | ADP_USB3_CS_2_ADBW_MASK);
2127 	val |= dbw << ADP_USB3_CS_2_ADBW_SHIFT;
2128 	val |= ubw;
2129 
2130 	return tb_port_write(port, &val, TB_CFG_PORT,
2131 			     port->cap_adap + ADP_USB3_CS_2, 1);
2132 }
2133 
2134 /**
2135  * usb4_usb3_port_allocate_bandwidth() - Allocate bandwidth for USB3
2136  * @port: USB3 adapter port
2137  * @upstream_bw: New upstream bandwidth
2138  * @downstream_bw: New downstream bandwidth
2139  *
2140  * This can be used to set how much bandwidth is allocated for the USB3
2141  * tunneled isochronous traffic. @upstream_bw and @downstream_bw are the
2142  * new values programmed to the USB3 adapter allocation registers. If
2143  * the values are lower than what is currently consumed the allocation
2144  * is set to what is currently consumed instead (consumed bandwidth
2145  * cannot be taken away by CM). The actual new values are returned in
2146  * @upstream_bw and @downstream_bw.
2147  *
2148  * Returns %0 in case of success and negative errno if there was a
2149  * failure.
2150  */
2151 int usb4_usb3_port_allocate_bandwidth(struct tb_port *port, int *upstream_bw,
2152 				      int *downstream_bw)
2153 {
2154 	int ret, consumed_up, consumed_down, allocate_up, allocate_down;
2155 
2156 	ret = usb4_usb3_port_set_cm_request(port);
2157 	if (ret)
2158 		return ret;
2159 
2160 	ret = usb4_usb3_port_read_consumed_bandwidth(port, &consumed_up,
2161 						     &consumed_down);
2162 	if (ret)
2163 		goto err_request;
2164 
2165 	/* Don't allow it go lower than what is consumed */
2166 	allocate_up = max(*upstream_bw, consumed_up);
2167 	allocate_down = max(*downstream_bw, consumed_down);
2168 
2169 	ret = usb4_usb3_port_write_allocated_bandwidth(port, allocate_up,
2170 						       allocate_down);
2171 	if (ret)
2172 		goto err_request;
2173 
2174 	*upstream_bw = allocate_up;
2175 	*downstream_bw = allocate_down;
2176 
2177 err_request:
2178 	usb4_usb3_port_clear_cm_request(port);
2179 	return ret;
2180 }
2181 
2182 /**
2183  * usb4_usb3_port_release_bandwidth() - Release allocated USB3 bandwidth
2184  * @port: USB3 adapter port
2185  * @upstream_bw: New allocated upstream bandwidth
2186  * @downstream_bw: New allocated downstream bandwidth
2187  *
2188  * Releases USB3 allocated bandwidth down to what is actually consumed.
2189  * The new bandwidth is returned in @upstream_bw and @downstream_bw.
2190  *
2191  * Returns 0% in success and negative errno in case of failure.
2192  */
2193 int usb4_usb3_port_release_bandwidth(struct tb_port *port, int *upstream_bw,
2194 				     int *downstream_bw)
2195 {
2196 	int ret, consumed_up, consumed_down;
2197 
2198 	ret = usb4_usb3_port_set_cm_request(port);
2199 	if (ret)
2200 		return ret;
2201 
2202 	ret = usb4_usb3_port_read_consumed_bandwidth(port, &consumed_up,
2203 						     &consumed_down);
2204 	if (ret)
2205 		goto err_request;
2206 
2207 	/*
2208 	 * Always keep 1000 Mb/s to make sure xHCI has at least some
2209 	 * bandwidth available for isochronous traffic.
2210 	 */
2211 	if (consumed_up < 1000)
2212 		consumed_up = 1000;
2213 	if (consumed_down < 1000)
2214 		consumed_down = 1000;
2215 
2216 	ret = usb4_usb3_port_write_allocated_bandwidth(port, consumed_up,
2217 						       consumed_down);
2218 	if (ret)
2219 		goto err_request;
2220 
2221 	*upstream_bw = consumed_up;
2222 	*downstream_bw = consumed_down;
2223 
2224 err_request:
2225 	usb4_usb3_port_clear_cm_request(port);
2226 	return ret;
2227 }
2228 
2229 static bool is_usb4_dpin(const struct tb_port *port)
2230 {
2231 	if (!tb_port_is_dpin(port))
2232 		return false;
2233 	if (!tb_switch_is_usb4(port->sw))
2234 		return false;
2235 	return true;
2236 }
2237 
2238 /**
2239  * usb4_dp_port_set_cm_id() - Assign CM ID to the DP IN adapter
2240  * @port: DP IN adapter
2241  * @cm_id: CM ID to assign
2242  *
2243  * Sets CM ID for the @port. Returns %0 on success and negative errno
2244  * otherwise. Speficially returns %-EOPNOTSUPP if the @port does not
2245  * support this.
2246  */
2247 int usb4_dp_port_set_cm_id(struct tb_port *port, int cm_id)
2248 {
2249 	u32 val;
2250 	int ret;
2251 
2252 	if (!is_usb4_dpin(port))
2253 		return -EOPNOTSUPP;
2254 
2255 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2256 			   port->cap_adap + ADP_DP_CS_2, 1);
2257 	if (ret)
2258 		return ret;
2259 
2260 	val &= ~ADP_DP_CS_2_CM_ID_MASK;
2261 	val |= cm_id << ADP_DP_CS_2_CM_ID_SHIFT;
2262 
2263 	return tb_port_write(port, &val, TB_CFG_PORT,
2264 			     port->cap_adap + ADP_DP_CS_2, 1);
2265 }
2266 
2267 /**
2268  * usb4_dp_port_bw_mode_supported() - Is the bandwidth allocation mode supported
2269  * @port: DP IN adapter to check
2270  *
2271  * Can be called to any DP IN adapter. Returns true if the adapter
2272  * supports USB4 bandwidth allocation mode, false otherwise.
2273  */
2274 bool usb4_dp_port_bw_mode_supported(struct tb_port *port)
2275 {
2276 	int ret;
2277 	u32 val;
2278 
2279 	if (!is_usb4_dpin(port))
2280 		return false;
2281 
2282 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2283 			   port->cap_adap + DP_LOCAL_CAP, 1);
2284 	if (ret)
2285 		return false;
2286 
2287 	return !!(val & DP_COMMON_CAP_BW_MODE);
2288 }
2289 
2290 /**
2291  * usb4_dp_port_bw_mode_enabled() - Is the bandwidth allocation mode enabled
2292  * @port: DP IN adapter to check
2293  *
2294  * Can be called to any DP IN adapter. Returns true if the bandwidth
2295  * allocation mode has been enabled, false otherwise.
2296  */
2297 bool usb4_dp_port_bw_mode_enabled(struct tb_port *port)
2298 {
2299 	int ret;
2300 	u32 val;
2301 
2302 	if (!is_usb4_dpin(port))
2303 		return false;
2304 
2305 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2306 			   port->cap_adap + ADP_DP_CS_8, 1);
2307 	if (ret)
2308 		return false;
2309 
2310 	return !!(val & ADP_DP_CS_8_DPME);
2311 }
2312 
2313 /**
2314  * usb4_dp_port_set_cm_bw_mode_supported() - Set/clear CM support for bandwidth allocation mode
2315  * @port: DP IN adapter
2316  * @supported: Does the CM support bandwidth allocation mode
2317  *
2318  * Can be called to any DP IN adapter. Sets or clears the CM support bit
2319  * of the DP IN adapter. Returns %0 in success and negative errno
2320  * otherwise. Specifically returns %-OPNOTSUPP if the passed in adapter
2321  * does not support this.
2322  */
2323 int usb4_dp_port_set_cm_bw_mode_supported(struct tb_port *port, bool supported)
2324 {
2325 	u32 val;
2326 	int ret;
2327 
2328 	if (!is_usb4_dpin(port))
2329 		return -EOPNOTSUPP;
2330 
2331 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2332 			   port->cap_adap + ADP_DP_CS_2, 1);
2333 	if (ret)
2334 		return ret;
2335 
2336 	if (supported)
2337 		val |= ADP_DP_CS_2_CMMS;
2338 	else
2339 		val &= ~ADP_DP_CS_2_CMMS;
2340 
2341 	return tb_port_write(port, &val, TB_CFG_PORT,
2342 			     port->cap_adap + ADP_DP_CS_2, 1);
2343 }
2344 
2345 /**
2346  * usb4_dp_port_group_id() - Return Group ID assigned for the adapter
2347  * @port: DP IN adapter
2348  *
2349  * Reads bandwidth allocation Group ID from the DP IN adapter and
2350  * returns it. If the adapter does not support setting Group_ID
2351  * %-EOPNOTSUPP is returned.
2352  */
2353 int usb4_dp_port_group_id(struct tb_port *port)
2354 {
2355 	u32 val;
2356 	int ret;
2357 
2358 	if (!is_usb4_dpin(port))
2359 		return -EOPNOTSUPP;
2360 
2361 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2362 			   port->cap_adap + ADP_DP_CS_2, 1);
2363 	if (ret)
2364 		return ret;
2365 
2366 	return (val & ADP_DP_CS_2_GROUP_ID_MASK) >> ADP_DP_CS_2_GROUP_ID_SHIFT;
2367 }
2368 
2369 /**
2370  * usb4_dp_port_set_group_id() - Set adapter Group ID
2371  * @port: DP IN adapter
2372  * @group_id: Group ID for the adapter
2373  *
2374  * Sets bandwidth allocation mode Group ID for the DP IN adapter.
2375  * Returns %0 in case of success and negative errno otherwise.
2376  * Specifically returns %-EOPNOTSUPP if the adapter does not support
2377  * this.
2378  */
2379 int usb4_dp_port_set_group_id(struct tb_port *port, int group_id)
2380 {
2381 	u32 val;
2382 	int ret;
2383 
2384 	if (!is_usb4_dpin(port))
2385 		return -EOPNOTSUPP;
2386 
2387 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2388 			   port->cap_adap + ADP_DP_CS_2, 1);
2389 	if (ret)
2390 		return ret;
2391 
2392 	val &= ~ADP_DP_CS_2_GROUP_ID_MASK;
2393 	val |= group_id << ADP_DP_CS_2_GROUP_ID_SHIFT;
2394 
2395 	return tb_port_write(port, &val, TB_CFG_PORT,
2396 			     port->cap_adap + ADP_DP_CS_2, 1);
2397 }
2398 
2399 /**
2400  * usb4_dp_port_nrd() - Read non-reduced rate and lanes
2401  * @port: DP IN adapter
2402  * @rate: Non-reduced rate in Mb/s is placed here
2403  * @lanes: Non-reduced lanes are placed here
2404  *
2405  * Reads the non-reduced rate and lanes from the DP IN adapter. Returns
2406  * %0 in success and negative errno otherwise. Specifically returns
2407  * %-EOPNOTSUPP if the adapter does not support this.
2408  */
2409 int usb4_dp_port_nrd(struct tb_port *port, int *rate, int *lanes)
2410 {
2411 	u32 val, tmp;
2412 	int ret;
2413 
2414 	if (!is_usb4_dpin(port))
2415 		return -EOPNOTSUPP;
2416 
2417 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2418 			   port->cap_adap + ADP_DP_CS_2, 1);
2419 	if (ret)
2420 		return ret;
2421 
2422 	tmp = (val & ADP_DP_CS_2_NRD_MLR_MASK) >> ADP_DP_CS_2_NRD_MLR_SHIFT;
2423 	switch (tmp) {
2424 	case DP_COMMON_CAP_RATE_RBR:
2425 		*rate = 1620;
2426 		break;
2427 	case DP_COMMON_CAP_RATE_HBR:
2428 		*rate = 2700;
2429 		break;
2430 	case DP_COMMON_CAP_RATE_HBR2:
2431 		*rate = 5400;
2432 		break;
2433 	case DP_COMMON_CAP_RATE_HBR3:
2434 		*rate = 8100;
2435 		break;
2436 	}
2437 
2438 	tmp = val & ADP_DP_CS_2_NRD_MLC_MASK;
2439 	switch (tmp) {
2440 	case DP_COMMON_CAP_1_LANE:
2441 		*lanes = 1;
2442 		break;
2443 	case DP_COMMON_CAP_2_LANES:
2444 		*lanes = 2;
2445 		break;
2446 	case DP_COMMON_CAP_4_LANES:
2447 		*lanes = 4;
2448 		break;
2449 	}
2450 
2451 	return 0;
2452 }
2453 
2454 /**
2455  * usb4_dp_port_set_nrd() - Set non-reduced rate and lanes
2456  * @port: DP IN adapter
2457  * @rate: Non-reduced rate in Mb/s
2458  * @lanes: Non-reduced lanes
2459  *
2460  * Before the capabilities reduction this function can be used to set
2461  * the non-reduced values for the DP IN adapter. Returns %0 in success
2462  * and negative errno otherwise. If the adapter does not support this
2463  * %-EOPNOTSUPP is returned.
2464  */
2465 int usb4_dp_port_set_nrd(struct tb_port *port, int rate, int lanes)
2466 {
2467 	u32 val;
2468 	int ret;
2469 
2470 	if (!is_usb4_dpin(port))
2471 		return -EOPNOTSUPP;
2472 
2473 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2474 			   port->cap_adap + ADP_DP_CS_2, 1);
2475 	if (ret)
2476 		return ret;
2477 
2478 	val &= ~ADP_DP_CS_2_NRD_MLR_MASK;
2479 
2480 	switch (rate) {
2481 	case 1620:
2482 		break;
2483 	case 2700:
2484 		val |= (DP_COMMON_CAP_RATE_HBR << ADP_DP_CS_2_NRD_MLR_SHIFT)
2485 			& ADP_DP_CS_2_NRD_MLR_MASK;
2486 		break;
2487 	case 5400:
2488 		val |= (DP_COMMON_CAP_RATE_HBR2 << ADP_DP_CS_2_NRD_MLR_SHIFT)
2489 			& ADP_DP_CS_2_NRD_MLR_MASK;
2490 		break;
2491 	case 8100:
2492 		val |= (DP_COMMON_CAP_RATE_HBR3 << ADP_DP_CS_2_NRD_MLR_SHIFT)
2493 			& ADP_DP_CS_2_NRD_MLR_MASK;
2494 		break;
2495 	default:
2496 		return -EINVAL;
2497 	}
2498 
2499 	val &= ~ADP_DP_CS_2_NRD_MLC_MASK;
2500 
2501 	switch (lanes) {
2502 	case 1:
2503 		break;
2504 	case 2:
2505 		val |= DP_COMMON_CAP_2_LANES;
2506 		break;
2507 	case 4:
2508 		val |= DP_COMMON_CAP_4_LANES;
2509 		break;
2510 	default:
2511 		return -EINVAL;
2512 	}
2513 
2514 	return tb_port_write(port, &val, TB_CFG_PORT,
2515 			     port->cap_adap + ADP_DP_CS_2, 1);
2516 }
2517 
2518 /**
2519  * usb4_dp_port_granularity() - Return granularity for the bandwidth values
2520  * @port: DP IN adapter
2521  *
2522  * Reads the programmed granularity from @port. If the DP IN adapter does
2523  * not support bandwidth allocation mode returns %-EOPNOTSUPP and negative
2524  * errno in other error cases.
2525  */
2526 int usb4_dp_port_granularity(struct tb_port *port)
2527 {
2528 	u32 val;
2529 	int ret;
2530 
2531 	if (!is_usb4_dpin(port))
2532 		return -EOPNOTSUPP;
2533 
2534 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2535 			   port->cap_adap + ADP_DP_CS_2, 1);
2536 	if (ret)
2537 		return ret;
2538 
2539 	val &= ADP_DP_CS_2_GR_MASK;
2540 	val >>= ADP_DP_CS_2_GR_SHIFT;
2541 
2542 	switch (val) {
2543 	case ADP_DP_CS_2_GR_0_25G:
2544 		return 250;
2545 	case ADP_DP_CS_2_GR_0_5G:
2546 		return 500;
2547 	case ADP_DP_CS_2_GR_1G:
2548 		return 1000;
2549 	}
2550 
2551 	return -EINVAL;
2552 }
2553 
2554 /**
2555  * usb4_dp_port_set_granularity() - Set granularity for the bandwidth values
2556  * @port: DP IN adapter
2557  * @granularity: Granularity in Mb/s. Supported values: 1000, 500 and 250.
2558  *
2559  * Sets the granularity used with the estimated, allocated and requested
2560  * bandwidth. Returns %0 in success and negative errno otherwise. If the
2561  * adapter does not support this %-EOPNOTSUPP is returned.
2562  */
2563 int usb4_dp_port_set_granularity(struct tb_port *port, int granularity)
2564 {
2565 	u32 val;
2566 	int ret;
2567 
2568 	if (!is_usb4_dpin(port))
2569 		return -EOPNOTSUPP;
2570 
2571 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2572 			   port->cap_adap + ADP_DP_CS_2, 1);
2573 	if (ret)
2574 		return ret;
2575 
2576 	val &= ~ADP_DP_CS_2_GR_MASK;
2577 
2578 	switch (granularity) {
2579 	case 250:
2580 		val |= ADP_DP_CS_2_GR_0_25G << ADP_DP_CS_2_GR_SHIFT;
2581 		break;
2582 	case 500:
2583 		val |= ADP_DP_CS_2_GR_0_5G << ADP_DP_CS_2_GR_SHIFT;
2584 		break;
2585 	case 1000:
2586 		val |= ADP_DP_CS_2_GR_1G << ADP_DP_CS_2_GR_SHIFT;
2587 		break;
2588 	default:
2589 		return -EINVAL;
2590 	}
2591 
2592 	return tb_port_write(port, &val, TB_CFG_PORT,
2593 			     port->cap_adap + ADP_DP_CS_2, 1);
2594 }
2595 
2596 /**
2597  * usb4_dp_port_set_estimated_bw() - Set estimated bandwidth
2598  * @port: DP IN adapter
2599  * @bw: Estimated bandwidth in Mb/s.
2600  *
2601  * Sets the estimated bandwidth to @bw. Set the granularity by calling
2602  * usb4_dp_port_set_granularity() before calling this. The @bw is round
2603  * down to the closest granularity multiplier. Returns %0 in success
2604  * and negative errno otherwise. Specifically returns %-EOPNOTSUPP if
2605  * the adapter does not support this.
2606  */
2607 int usb4_dp_port_set_estimated_bw(struct tb_port *port, int bw)
2608 {
2609 	u32 val, granularity;
2610 	int ret;
2611 
2612 	if (!is_usb4_dpin(port))
2613 		return -EOPNOTSUPP;
2614 
2615 	ret = usb4_dp_port_granularity(port);
2616 	if (ret < 0)
2617 		return ret;
2618 	granularity = ret;
2619 
2620 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2621 			   port->cap_adap + ADP_DP_CS_2, 1);
2622 	if (ret)
2623 		return ret;
2624 
2625 	val &= ~ADP_DP_CS_2_ESTIMATED_BW_MASK;
2626 	val |= (bw / granularity) << ADP_DP_CS_2_ESTIMATED_BW_SHIFT;
2627 
2628 	return tb_port_write(port, &val, TB_CFG_PORT,
2629 			     port->cap_adap + ADP_DP_CS_2, 1);
2630 }
2631 
2632 /**
2633  * usb4_dp_port_allocated_bw() - Return allocated bandwidth
2634  * @port: DP IN adapter
2635  *
2636  * Reads and returns allocated bandwidth for @port in Mb/s (taking into
2637  * account the programmed granularity). Returns negative errno in case
2638  * of error.
2639  */
2640 int usb4_dp_port_allocated_bw(struct tb_port *port)
2641 {
2642 	u32 val, granularity;
2643 	int ret;
2644 
2645 	if (!is_usb4_dpin(port))
2646 		return -EOPNOTSUPP;
2647 
2648 	ret = usb4_dp_port_granularity(port);
2649 	if (ret < 0)
2650 		return ret;
2651 	granularity = ret;
2652 
2653 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2654 			   port->cap_adap + DP_STATUS, 1);
2655 	if (ret)
2656 		return ret;
2657 
2658 	val &= DP_STATUS_ALLOCATED_BW_MASK;
2659 	val >>= DP_STATUS_ALLOCATED_BW_SHIFT;
2660 
2661 	return val * granularity;
2662 }
2663 
2664 static int __usb4_dp_port_set_cm_ack(struct tb_port *port, bool ack)
2665 {
2666 	u32 val;
2667 	int ret;
2668 
2669 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2670 			   port->cap_adap + ADP_DP_CS_2, 1);
2671 	if (ret)
2672 		return ret;
2673 
2674 	if (ack)
2675 		val |= ADP_DP_CS_2_CA;
2676 	else
2677 		val &= ~ADP_DP_CS_2_CA;
2678 
2679 	return tb_port_write(port, &val, TB_CFG_PORT,
2680 			     port->cap_adap + ADP_DP_CS_2, 1);
2681 }
2682 
2683 static inline int usb4_dp_port_set_cm_ack(struct tb_port *port)
2684 {
2685 	return __usb4_dp_port_set_cm_ack(port, true);
2686 }
2687 
2688 static int usb4_dp_port_wait_and_clear_cm_ack(struct tb_port *port,
2689 					      int timeout_msec)
2690 {
2691 	ktime_t end;
2692 	u32 val;
2693 	int ret;
2694 
2695 	ret = __usb4_dp_port_set_cm_ack(port, false);
2696 	if (ret)
2697 		return ret;
2698 
2699 	end = ktime_add_ms(ktime_get(), timeout_msec);
2700 	do {
2701 		ret = tb_port_read(port, &val, TB_CFG_PORT,
2702 				   port->cap_adap + ADP_DP_CS_8, 1);
2703 		if (ret)
2704 			return ret;
2705 
2706 		if (!(val & ADP_DP_CS_8_DR))
2707 			break;
2708 
2709 		usleep_range(50, 100);
2710 	} while (ktime_before(ktime_get(), end));
2711 
2712 	if (val & ADP_DP_CS_8_DR)
2713 		return -ETIMEDOUT;
2714 
2715 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2716 			   port->cap_adap + ADP_DP_CS_2, 1);
2717 	if (ret)
2718 		return ret;
2719 
2720 	val &= ~ADP_DP_CS_2_CA;
2721 	return tb_port_write(port, &val, TB_CFG_PORT,
2722 			     port->cap_adap + ADP_DP_CS_2, 1);
2723 }
2724 
2725 /**
2726  * usb4_dp_port_allocate_bw() - Set allocated bandwidth
2727  * @port: DP IN adapter
2728  * @bw: New allocated bandwidth in Mb/s
2729  *
2730  * Communicates the new allocated bandwidth with the DPCD (graphics
2731  * driver). Takes into account the programmed granularity. Returns %0 in
2732  * success and negative errno in case of error.
2733  */
2734 int usb4_dp_port_allocate_bw(struct tb_port *port, int bw)
2735 {
2736 	u32 val, granularity;
2737 	int ret;
2738 
2739 	if (!is_usb4_dpin(port))
2740 		return -EOPNOTSUPP;
2741 
2742 	ret = usb4_dp_port_granularity(port);
2743 	if (ret < 0)
2744 		return ret;
2745 	granularity = ret;
2746 
2747 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2748 			   port->cap_adap + DP_STATUS, 1);
2749 	if (ret)
2750 		return ret;
2751 
2752 	val &= ~DP_STATUS_ALLOCATED_BW_MASK;
2753 	val |= (bw / granularity) << DP_STATUS_ALLOCATED_BW_SHIFT;
2754 
2755 	ret = tb_port_write(port, &val, TB_CFG_PORT,
2756 			    port->cap_adap + DP_STATUS, 1);
2757 	if (ret)
2758 		return ret;
2759 
2760 	ret = usb4_dp_port_set_cm_ack(port);
2761 	if (ret)
2762 		return ret;
2763 
2764 	return usb4_dp_port_wait_and_clear_cm_ack(port, 500);
2765 }
2766 
2767 /**
2768  * usb4_dp_port_requested_bw() - Read requested bandwidth
2769  * @port: DP IN adapter
2770  *
2771  * Reads the DPCD (graphics driver) requested bandwidth and returns it
2772  * in Mb/s. Takes the programmed granularity into account. In case of
2773  * error returns negative errno. Specifically returns %-EOPNOTSUPP if
2774  * the adapter does not support bandwidth allocation mode, and %ENODATA
2775  * if there is no active bandwidth request from the graphics driver.
2776  */
2777 int usb4_dp_port_requested_bw(struct tb_port *port)
2778 {
2779 	u32 val, granularity;
2780 	int ret;
2781 
2782 	if (!is_usb4_dpin(port))
2783 		return -EOPNOTSUPP;
2784 
2785 	ret = usb4_dp_port_granularity(port);
2786 	if (ret < 0)
2787 		return ret;
2788 	granularity = ret;
2789 
2790 	ret = tb_port_read(port, &val, TB_CFG_PORT,
2791 			   port->cap_adap + ADP_DP_CS_8, 1);
2792 	if (ret)
2793 		return ret;
2794 
2795 	if (!(val & ADP_DP_CS_8_DR))
2796 		return -ENODATA;
2797 
2798 	return (val & ADP_DP_CS_8_REQUESTED_BW_MASK) * granularity;
2799 }
2800