xref: /linux/drivers/thunderbolt/debugfs.c (revision d7b4e3287ca3a7baf66efd9158498e551a9550da)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Debugfs interface
4  *
5  * Copyright (C) 2020, Intel Corporation
6  * Authors: Gil Fine <gil.fine@intel.com>
7  *	    Mika Westerberg <mika.westerberg@linux.intel.com>
8  */
9 
10 #include <linux/debugfs.h>
11 #include <linux/pm_runtime.h>
12 #include <linux/uaccess.h>
13 
14 #include "tb.h"
15 #include "sb_regs.h"
16 
17 #define PORT_CAP_V1_PCIE_LEN	1
18 #define PORT_CAP_V2_PCIE_LEN	2
19 #define PORT_CAP_POWER_LEN	2
20 #define PORT_CAP_LANE_LEN	3
21 #define PORT_CAP_USB3_LEN	5
22 #define PORT_CAP_DP_V1_LEN	9
23 #define PORT_CAP_DP_V2_LEN	14
24 #define PORT_CAP_TMU_V1_LEN	8
25 #define PORT_CAP_TMU_V2_LEN	10
26 #define PORT_CAP_BASIC_LEN	9
27 #define PORT_CAP_USB4_LEN	20
28 
29 #define SWITCH_CAP_TMU_LEN	26
30 #define SWITCH_CAP_BASIC_LEN	27
31 
32 #define PATH_LEN		2
33 
34 #define COUNTER_SET_LEN		3
35 
36 #define DEBUGFS_ATTR(__space, __write)					\
37 static int __space ## _open(struct inode *inode, struct file *file)	\
38 {									\
39 	return single_open(file, __space ## _show, inode->i_private);	\
40 }									\
41 									\
42 static const struct file_operations __space ## _fops = {		\
43 	.owner = THIS_MODULE,						\
44 	.open = __space ## _open,					\
45 	.release = single_release,					\
46 	.read  = seq_read,						\
47 	.write = __write,						\
48 	.llseek = seq_lseek,						\
49 }
50 
51 #define DEBUGFS_ATTR_RO(__space)					\
52 	DEBUGFS_ATTR(__space, NULL)
53 
54 #define DEBUGFS_ATTR_RW(__space)					\
55 	DEBUGFS_ATTR(__space, __space ## _write)
56 
57 static struct dentry *tb_debugfs_root;
58 
59 static void *validate_and_copy_from_user(const void __user *user_buf,
60 					 size_t *count)
61 {
62 	size_t nbytes;
63 	void *buf;
64 
65 	if (!*count)
66 		return ERR_PTR(-EINVAL);
67 
68 	if (!access_ok(user_buf, *count))
69 		return ERR_PTR(-EFAULT);
70 
71 	buf = (void *)get_zeroed_page(GFP_KERNEL);
72 	if (!buf)
73 		return ERR_PTR(-ENOMEM);
74 
75 	nbytes = min_t(size_t, *count, PAGE_SIZE);
76 	if (copy_from_user(buf, user_buf, nbytes)) {
77 		free_page((unsigned long)buf);
78 		return ERR_PTR(-EFAULT);
79 	}
80 
81 	*count = nbytes;
82 	return buf;
83 }
84 
85 static bool parse_line(char **line, u32 *offs, u32 *val, int short_fmt_len,
86 		       int long_fmt_len)
87 {
88 	char *token;
89 	u32 v[5];
90 	int ret;
91 
92 	token = strsep(line, "\n");
93 	if (!token)
94 		return false;
95 
96 	/*
97 	 * For Adapter/Router configuration space:
98 	 * Short format is: offset value\n
99 	 *		    v[0]   v[1]
100 	 * Long format as produced from the read side:
101 	 * offset relative_offset cap_id vs_cap_id value\n
102 	 * v[0]   v[1]            v[2]   v[3]      v[4]
103 	 *
104 	 * For Counter configuration space:
105 	 * Short format is: offset\n
106 	 *		    v[0]
107 	 * Long format as produced from the read side:
108 	 * offset relative_offset counter_id value\n
109 	 * v[0]   v[1]            v[2]       v[3]
110 	 */
111 	ret = sscanf(token, "%i %i %i %i %i", &v[0], &v[1], &v[2], &v[3], &v[4]);
112 	/* In case of Counters, clear counter, "val" content is NA */
113 	if (ret == short_fmt_len) {
114 		*offs = v[0];
115 		*val = v[short_fmt_len - 1];
116 		return true;
117 	} else if (ret == long_fmt_len) {
118 		*offs = v[0];
119 		*val = v[long_fmt_len - 1];
120 		return true;
121 	}
122 
123 	return false;
124 }
125 
126 #if IS_ENABLED(CONFIG_USB4_DEBUGFS_WRITE)
127 static ssize_t regs_write(struct tb_switch *sw, struct tb_port *port,
128 			  const char __user *user_buf, size_t count,
129 			  loff_t *ppos)
130 {
131 	struct tb *tb = sw->tb;
132 	char *line, *buf;
133 	u32 val, offset;
134 	int ret = 0;
135 
136 	buf = validate_and_copy_from_user(user_buf, &count);
137 	if (IS_ERR(buf))
138 		return PTR_ERR(buf);
139 
140 	pm_runtime_get_sync(&sw->dev);
141 
142 	if (mutex_lock_interruptible(&tb->lock)) {
143 		ret = -ERESTARTSYS;
144 		goto out;
145 	}
146 
147 	/* User did hardware changes behind the driver's back */
148 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
149 
150 	line = buf;
151 	while (parse_line(&line, &offset, &val, 2, 5)) {
152 		if (port)
153 			ret = tb_port_write(port, &val, TB_CFG_PORT, offset, 1);
154 		else
155 			ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, offset, 1);
156 		if (ret)
157 			break;
158 	}
159 
160 	mutex_unlock(&tb->lock);
161 
162 out:
163 	pm_runtime_mark_last_busy(&sw->dev);
164 	pm_runtime_put_autosuspend(&sw->dev);
165 	free_page((unsigned long)buf);
166 
167 	return ret < 0 ? ret : count;
168 }
169 
170 static ssize_t port_regs_write(struct file *file, const char __user *user_buf,
171 			       size_t count, loff_t *ppos)
172 {
173 	struct seq_file *s = file->private_data;
174 	struct tb_port *port = s->private;
175 
176 	return regs_write(port->sw, port, user_buf, count, ppos);
177 }
178 
179 static ssize_t switch_regs_write(struct file *file, const char __user *user_buf,
180 				 size_t count, loff_t *ppos)
181 {
182 	struct seq_file *s = file->private_data;
183 	struct tb_switch *sw = s->private;
184 
185 	return regs_write(sw, NULL, user_buf, count, ppos);
186 }
187 #define DEBUGFS_MODE		0600
188 #else
189 #define port_regs_write		NULL
190 #define switch_regs_write	NULL
191 #define DEBUGFS_MODE		0400
192 #endif
193 
194 #if IS_ENABLED(CONFIG_USB4_DEBUGFS_MARGINING)
195 /**
196  * struct tb_margining - Lane margining support
197  * @caps: Port lane margining capabilities
198  * @results: Last lane margining results
199  * @lanes: %0, %1 or %7 (all)
200  * @min_ber_level: Minimum supported BER level contour value
201  * @max_ber_level: Maximum supported BER level contour value
202  * @ber_level: Current BER level contour value
203  * @voltage_steps: Number of mandatory voltage steps
204  * @max_voltage_offset: Maximum mandatory voltage offset (in mV)
205  * @time_steps: Number of time margin steps
206  * @max_time_offset: Maximum time margin offset (in mUI)
207  * @software: %true if software margining is used instead of hardware
208  * @time: %true if time margining is used instead of voltage
209  * @right_high: %false if left/low margin test is performed, %true if
210  *		right/high
211  */
212 struct tb_margining {
213 	u32 caps[2];
214 	u32 results[2];
215 	unsigned int lanes;
216 	unsigned int min_ber_level;
217 	unsigned int max_ber_level;
218 	unsigned int ber_level;
219 	unsigned int voltage_steps;
220 	unsigned int max_voltage_offset;
221 	unsigned int time_steps;
222 	unsigned int max_time_offset;
223 	bool software;
224 	bool time;
225 	bool right_high;
226 };
227 
228 static bool supports_software(const struct usb4_port *usb4)
229 {
230 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_SW;
231 }
232 
233 static bool supports_hardware(const struct usb4_port *usb4)
234 {
235 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_HW;
236 }
237 
238 static bool both_lanes(const struct usb4_port *usb4)
239 {
240 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_2_LANES;
241 }
242 
243 static unsigned int independent_voltage_margins(const struct usb4_port *usb4)
244 {
245 	return (usb4->margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_INDP_MASK) >>
246 		USB4_MARGIN_CAP_0_VOLTAGE_INDP_SHIFT;
247 }
248 
249 static bool supports_time(const struct usb4_port *usb4)
250 {
251 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_TIME;
252 }
253 
254 /* Only applicable if supports_time() returns true */
255 static unsigned int independent_time_margins(const struct usb4_port *usb4)
256 {
257 	return (usb4->margining->caps[1] & USB4_MARGIN_CAP_1_TIME_INDP_MASK) >>
258 		USB4_MARGIN_CAP_1_TIME_INDP_SHIFT;
259 }
260 
261 static ssize_t
262 margining_ber_level_write(struct file *file, const char __user *user_buf,
263 			   size_t count, loff_t *ppos)
264 {
265 	struct seq_file *s = file->private_data;
266 	struct tb_port *port = s->private;
267 	struct usb4_port *usb4 = port->usb4;
268 	struct tb *tb = port->sw->tb;
269 	unsigned int val;
270 	int ret = 0;
271 	char *buf;
272 
273 	if (mutex_lock_interruptible(&tb->lock))
274 		return -ERESTARTSYS;
275 
276 	if (usb4->margining->software) {
277 		ret = -EINVAL;
278 		goto out_unlock;
279 	}
280 
281 	buf = validate_and_copy_from_user(user_buf, &count);
282 	if (IS_ERR(buf)) {
283 		ret = PTR_ERR(buf);
284 		goto out_unlock;
285 	}
286 
287 	buf[count - 1] = '\0';
288 
289 	ret = kstrtouint(buf, 10, &val);
290 	if (ret)
291 		goto out_free;
292 
293 	if (val < usb4->margining->min_ber_level ||
294 	    val > usb4->margining->max_ber_level) {
295 		ret = -EINVAL;
296 		goto out_free;
297 	}
298 
299 	usb4->margining->ber_level = val;
300 
301 out_free:
302 	free_page((unsigned long)buf);
303 out_unlock:
304 	mutex_unlock(&tb->lock);
305 
306 	return ret < 0 ? ret : count;
307 }
308 
309 static void ber_level_show(struct seq_file *s, unsigned int val)
310 {
311 	if (val % 2)
312 		seq_printf(s, "3 * 1e%d (%u)\n", -12 + (val + 1) / 2, val);
313 	else
314 		seq_printf(s, "1e%d (%u)\n", -12 + val / 2, val);
315 }
316 
317 static int margining_ber_level_show(struct seq_file *s, void *not_used)
318 {
319 	struct tb_port *port = s->private;
320 	struct usb4_port *usb4 = port->usb4;
321 
322 	if (usb4->margining->software)
323 		return -EINVAL;
324 	ber_level_show(s, usb4->margining->ber_level);
325 	return 0;
326 }
327 DEBUGFS_ATTR_RW(margining_ber_level);
328 
329 static int margining_caps_show(struct seq_file *s, void *not_used)
330 {
331 	struct tb_port *port = s->private;
332 	struct usb4_port *usb4 = port->usb4;
333 	struct tb *tb = port->sw->tb;
334 	u32 cap0, cap1;
335 
336 	if (mutex_lock_interruptible(&tb->lock))
337 		return -ERESTARTSYS;
338 
339 	/* Dump the raw caps first */
340 	cap0 = usb4->margining->caps[0];
341 	seq_printf(s, "0x%08x\n", cap0);
342 	cap1 = usb4->margining->caps[1];
343 	seq_printf(s, "0x%08x\n", cap1);
344 
345 	seq_printf(s, "# software margining: %s\n",
346 		   supports_software(usb4) ? "yes" : "no");
347 	if (supports_hardware(usb4)) {
348 		seq_puts(s, "# hardware margining: yes\n");
349 		seq_puts(s, "# minimum BER level contour: ");
350 		ber_level_show(s, usb4->margining->min_ber_level);
351 		seq_puts(s, "# maximum BER level contour: ");
352 		ber_level_show(s, usb4->margining->max_ber_level);
353 	} else {
354 		seq_puts(s, "# hardware margining: no\n");
355 	}
356 
357 	seq_printf(s, "# both lanes simultaneously: %s\n",
358 		  both_lanes(usb4) ? "yes" : "no");
359 	seq_printf(s, "# voltage margin steps: %u\n",
360 		   usb4->margining->voltage_steps);
361 	seq_printf(s, "# maximum voltage offset: %u mV\n",
362 		   usb4->margining->max_voltage_offset);
363 
364 	switch (independent_voltage_margins(usb4)) {
365 	case USB4_MARGIN_CAP_0_VOLTAGE_MIN:
366 		seq_puts(s, "# returns minimum between high and low voltage margins\n");
367 		break;
368 	case USB4_MARGIN_CAP_0_VOLTAGE_HL:
369 		seq_puts(s, "# returns high or low voltage margin\n");
370 		break;
371 	case USB4_MARGIN_CAP_0_VOLTAGE_BOTH:
372 		seq_puts(s, "# returns both high and low margins\n");
373 		break;
374 	}
375 
376 	if (supports_time(usb4)) {
377 		seq_puts(s, "# time margining: yes\n");
378 		seq_printf(s, "# time margining is destructive: %s\n",
379 			   cap1 & USB4_MARGIN_CAP_1_TIME_DESTR ? "yes" : "no");
380 
381 		switch (independent_time_margins(usb4)) {
382 		case USB4_MARGIN_CAP_1_TIME_MIN:
383 			seq_puts(s, "# returns minimum between left and right time margins\n");
384 			break;
385 		case USB4_MARGIN_CAP_1_TIME_LR:
386 			seq_puts(s, "# returns left or right margin\n");
387 			break;
388 		case USB4_MARGIN_CAP_1_TIME_BOTH:
389 			seq_puts(s, "# returns both left and right margins\n");
390 			break;
391 		}
392 
393 		seq_printf(s, "# time margin steps: %u\n",
394 			   usb4->margining->time_steps);
395 		seq_printf(s, "# maximum time offset: %u mUI\n",
396 			   usb4->margining->max_time_offset);
397 	} else {
398 		seq_puts(s, "# time margining: no\n");
399 	}
400 
401 	mutex_unlock(&tb->lock);
402 	return 0;
403 }
404 DEBUGFS_ATTR_RO(margining_caps);
405 
406 static ssize_t
407 margining_lanes_write(struct file *file, const char __user *user_buf,
408 		      size_t count, loff_t *ppos)
409 {
410 	struct seq_file *s = file->private_data;
411 	struct tb_port *port = s->private;
412 	struct usb4_port *usb4 = port->usb4;
413 	struct tb *tb = port->sw->tb;
414 	int ret = 0;
415 	char *buf;
416 
417 	buf = validate_and_copy_from_user(user_buf, &count);
418 	if (IS_ERR(buf))
419 		return PTR_ERR(buf);
420 
421 	buf[count - 1] = '\0';
422 
423 	if (mutex_lock_interruptible(&tb->lock)) {
424 		ret = -ERESTARTSYS;
425 		goto out_free;
426 	}
427 
428 	if (!strcmp(buf, "0")) {
429 		usb4->margining->lanes = 0;
430 	} else if (!strcmp(buf, "1")) {
431 		usb4->margining->lanes = 1;
432 	} else if (!strcmp(buf, "all")) {
433 		/* Needs to be supported */
434 		if (both_lanes(usb4))
435 			usb4->margining->lanes = 7;
436 		else
437 			ret = -EINVAL;
438 	} else {
439 		ret = -EINVAL;
440 	}
441 
442 	mutex_unlock(&tb->lock);
443 
444 out_free:
445 	free_page((unsigned long)buf);
446 	return ret < 0 ? ret : count;
447 }
448 
449 static int margining_lanes_show(struct seq_file *s, void *not_used)
450 {
451 	struct tb_port *port = s->private;
452 	struct usb4_port *usb4 = port->usb4;
453 	struct tb *tb = port->sw->tb;
454 	unsigned int lanes;
455 
456 	if (mutex_lock_interruptible(&tb->lock))
457 		return -ERESTARTSYS;
458 
459 	lanes = usb4->margining->lanes;
460 	if (both_lanes(usb4)) {
461 		if (!lanes)
462 			seq_puts(s, "[0] 1 all\n");
463 		else if (lanes == 1)
464 			seq_puts(s, "0 [1] all\n");
465 		else
466 			seq_puts(s, "0 1 [all]\n");
467 	} else {
468 		if (!lanes)
469 			seq_puts(s, "[0] 1\n");
470 		else
471 			seq_puts(s, "0 [1]\n");
472 	}
473 
474 	mutex_unlock(&tb->lock);
475 	return 0;
476 }
477 DEBUGFS_ATTR_RW(margining_lanes);
478 
479 static ssize_t margining_mode_write(struct file *file,
480 				   const char __user *user_buf,
481 				   size_t count, loff_t *ppos)
482 {
483 	struct seq_file *s = file->private_data;
484 	struct tb_port *port = s->private;
485 	struct usb4_port *usb4 = port->usb4;
486 	struct tb *tb = port->sw->tb;
487 	int ret = 0;
488 	char *buf;
489 
490 	buf = validate_and_copy_from_user(user_buf, &count);
491 	if (IS_ERR(buf))
492 		return PTR_ERR(buf);
493 
494 	buf[count - 1] = '\0';
495 
496 	if (mutex_lock_interruptible(&tb->lock)) {
497 		ret = -ERESTARTSYS;
498 		goto out_free;
499 	}
500 
501 	if (!strcmp(buf, "software")) {
502 		if (supports_software(usb4))
503 			usb4->margining->software = true;
504 		else
505 			ret = -EINVAL;
506 	} else if (!strcmp(buf, "hardware")) {
507 		if (supports_hardware(usb4))
508 			usb4->margining->software = false;
509 		else
510 			ret = -EINVAL;
511 	} else {
512 		ret = -EINVAL;
513 	}
514 
515 	mutex_unlock(&tb->lock);
516 
517 out_free:
518 	free_page((unsigned long)buf);
519 	return ret ? ret : count;
520 }
521 
522 static int margining_mode_show(struct seq_file *s, void *not_used)
523 {
524 	const struct tb_port *port = s->private;
525 	const struct usb4_port *usb4 = port->usb4;
526 	struct tb *tb = port->sw->tb;
527 	const char *space = "";
528 
529 	if (mutex_lock_interruptible(&tb->lock))
530 		return -ERESTARTSYS;
531 
532 	if (supports_software(usb4)) {
533 		if (usb4->margining->software)
534 			seq_puts(s, "[software]");
535 		else
536 			seq_puts(s, "software");
537 		space = " ";
538 	}
539 	if (supports_hardware(usb4)) {
540 		if (usb4->margining->software)
541 			seq_printf(s, "%shardware", space);
542 		else
543 			seq_printf(s, "%s[hardware]", space);
544 	}
545 
546 	mutex_unlock(&tb->lock);
547 
548 	seq_puts(s, "\n");
549 	return 0;
550 }
551 DEBUGFS_ATTR_RW(margining_mode);
552 
553 static int margining_run_write(void *data, u64 val)
554 {
555 	struct tb_port *port = data;
556 	struct usb4_port *usb4 = port->usb4;
557 	struct tb_switch *sw = port->sw;
558 	struct tb_margining *margining;
559 	struct tb_switch *down_sw;
560 	struct tb *tb = sw->tb;
561 	int ret, clx;
562 
563 	if (val != 1)
564 		return -EINVAL;
565 
566 	pm_runtime_get_sync(&sw->dev);
567 
568 	if (mutex_lock_interruptible(&tb->lock)) {
569 		ret = -ERESTARTSYS;
570 		goto out_rpm_put;
571 	}
572 
573 	if (tb_is_upstream_port(port))
574 		down_sw = sw;
575 	else if (port->remote)
576 		down_sw = port->remote->sw;
577 	else
578 		down_sw = NULL;
579 
580 	if (down_sw) {
581 		/*
582 		 * CL states may interfere with lane margining so
583 		 * disable them temporarily now.
584 		 */
585 		ret = tb_switch_clx_disable(down_sw);
586 		if (ret < 0) {
587 			tb_sw_warn(down_sw, "failed to disable CL states\n");
588 			goto out_unlock;
589 		}
590 		clx = ret;
591 	}
592 
593 	margining = usb4->margining;
594 
595 	if (margining->software) {
596 		tb_port_dbg(port, "running software %s lane margining for lanes %u\n",
597 			    margining->time ? "time" : "voltage", margining->lanes);
598 		ret = usb4_port_sw_margin(port, margining->lanes, margining->time,
599 					  margining->right_high,
600 					  USB4_MARGIN_SW_COUNTER_CLEAR);
601 		if (ret)
602 			goto out_clx;
603 
604 		ret = usb4_port_sw_margin_errors(port, &margining->results[0]);
605 	} else {
606 		tb_port_dbg(port, "running hardware %s lane margining for lanes %u\n",
607 			    margining->time ? "time" : "voltage", margining->lanes);
608 		/* Clear the results */
609 		margining->results[0] = 0;
610 		margining->results[1] = 0;
611 		ret = usb4_port_hw_margin(port, margining->lanes,
612 					  margining->ber_level, margining->time,
613 					  margining->right_high, margining->results);
614 	}
615 
616 out_clx:
617 	if (down_sw)
618 		tb_switch_clx_enable(down_sw, clx);
619 out_unlock:
620 	mutex_unlock(&tb->lock);
621 out_rpm_put:
622 	pm_runtime_mark_last_busy(&sw->dev);
623 	pm_runtime_put_autosuspend(&sw->dev);
624 
625 	return ret;
626 }
627 DEFINE_DEBUGFS_ATTRIBUTE(margining_run_fops, NULL, margining_run_write,
628 			 "%llu\n");
629 
630 static ssize_t margining_results_write(struct file *file,
631 				       const char __user *user_buf,
632 				       size_t count, loff_t *ppos)
633 {
634 	struct seq_file *s = file->private_data;
635 	struct tb_port *port = s->private;
636 	struct usb4_port *usb4 = port->usb4;
637 	struct tb *tb = port->sw->tb;
638 
639 	if (mutex_lock_interruptible(&tb->lock))
640 		return -ERESTARTSYS;
641 
642 	/* Just clear the results */
643 	usb4->margining->results[0] = 0;
644 	usb4->margining->results[1] = 0;
645 
646 	mutex_unlock(&tb->lock);
647 	return count;
648 }
649 
650 static void voltage_margin_show(struct seq_file *s,
651 				const struct tb_margining *margining, u8 val)
652 {
653 	unsigned int tmp, voltage;
654 
655 	tmp = val & USB4_MARGIN_HW_RES_1_MARGIN_MASK;
656 	voltage = tmp * margining->max_voltage_offset / margining->voltage_steps;
657 	seq_printf(s, "%u mV (%u)", voltage, tmp);
658 	if (val & USB4_MARGIN_HW_RES_1_EXCEEDS)
659 		seq_puts(s, " exceeds maximum");
660 	seq_puts(s, "\n");
661 }
662 
663 static void time_margin_show(struct seq_file *s,
664 			     const struct tb_margining *margining, u8 val)
665 {
666 	unsigned int tmp, interval;
667 
668 	tmp = val & USB4_MARGIN_HW_RES_1_MARGIN_MASK;
669 	interval = tmp * margining->max_time_offset / margining->time_steps;
670 	seq_printf(s, "%u mUI (%u)", interval, tmp);
671 	if (val & USB4_MARGIN_HW_RES_1_EXCEEDS)
672 		seq_puts(s, " exceeds maximum");
673 	seq_puts(s, "\n");
674 }
675 
676 static int margining_results_show(struct seq_file *s, void *not_used)
677 {
678 	struct tb_port *port = s->private;
679 	struct usb4_port *usb4 = port->usb4;
680 	struct tb_margining *margining;
681 	struct tb *tb = port->sw->tb;
682 
683 	if (mutex_lock_interruptible(&tb->lock))
684 		return -ERESTARTSYS;
685 
686 	margining = usb4->margining;
687 	/* Dump the raw results first */
688 	seq_printf(s, "0x%08x\n", margining->results[0]);
689 	/* Only the hardware margining has two result dwords */
690 	if (!margining->software) {
691 		unsigned int val;
692 
693 		seq_printf(s, "0x%08x\n", margining->results[1]);
694 
695 		if (margining->time) {
696 			if (!margining->lanes || margining->lanes == 7) {
697 				val = margining->results[1];
698 				seq_puts(s, "# lane 0 right time margin: ");
699 				time_margin_show(s, margining, val);
700 				val = margining->results[1] >>
701 					USB4_MARGIN_HW_RES_1_L0_LL_MARGIN_SHIFT;
702 				seq_puts(s, "# lane 0 left time margin: ");
703 				time_margin_show(s, margining, val);
704 			}
705 			if (margining->lanes == 1 || margining->lanes == 7) {
706 				val = margining->results[1] >>
707 					USB4_MARGIN_HW_RES_1_L1_RH_MARGIN_SHIFT;
708 				seq_puts(s, "# lane 1 right time margin: ");
709 				time_margin_show(s, margining, val);
710 				val = margining->results[1] >>
711 					USB4_MARGIN_HW_RES_1_L1_LL_MARGIN_SHIFT;
712 				seq_puts(s, "# lane 1 left time margin: ");
713 				time_margin_show(s, margining, val);
714 			}
715 		} else {
716 			if (!margining->lanes || margining->lanes == 7) {
717 				val = margining->results[1];
718 				seq_puts(s, "# lane 0 high voltage margin: ");
719 				voltage_margin_show(s, margining, val);
720 				val = margining->results[1] >>
721 					USB4_MARGIN_HW_RES_1_L0_LL_MARGIN_SHIFT;
722 				seq_puts(s, "# lane 0 low voltage margin: ");
723 				voltage_margin_show(s, margining, val);
724 			}
725 			if (margining->lanes == 1 || margining->lanes == 7) {
726 				val = margining->results[1] >>
727 					USB4_MARGIN_HW_RES_1_L1_RH_MARGIN_SHIFT;
728 				seq_puts(s, "# lane 1 high voltage margin: ");
729 				voltage_margin_show(s, margining, val);
730 				val = margining->results[1] >>
731 					USB4_MARGIN_HW_RES_1_L1_LL_MARGIN_SHIFT;
732 				seq_puts(s, "# lane 1 low voltage margin: ");
733 				voltage_margin_show(s, margining, val);
734 			}
735 		}
736 	}
737 
738 	mutex_unlock(&tb->lock);
739 	return 0;
740 }
741 DEBUGFS_ATTR_RW(margining_results);
742 
743 static ssize_t margining_test_write(struct file *file,
744 				    const char __user *user_buf,
745 				    size_t count, loff_t *ppos)
746 {
747 	struct seq_file *s = file->private_data;
748 	struct tb_port *port = s->private;
749 	struct usb4_port *usb4 = port->usb4;
750 	struct tb *tb = port->sw->tb;
751 	int ret = 0;
752 	char *buf;
753 
754 	buf = validate_and_copy_from_user(user_buf, &count);
755 	if (IS_ERR(buf))
756 		return PTR_ERR(buf);
757 
758 	buf[count - 1] = '\0';
759 
760 	if (mutex_lock_interruptible(&tb->lock)) {
761 		ret = -ERESTARTSYS;
762 		goto out_free;
763 	}
764 
765 	if (!strcmp(buf, "time") && supports_time(usb4))
766 		usb4->margining->time = true;
767 	else if (!strcmp(buf, "voltage"))
768 		usb4->margining->time = false;
769 	else
770 		ret = -EINVAL;
771 
772 	mutex_unlock(&tb->lock);
773 
774 out_free:
775 	free_page((unsigned long)buf);
776 	return ret ? ret : count;
777 }
778 
779 static int margining_test_show(struct seq_file *s, void *not_used)
780 {
781 	struct tb_port *port = s->private;
782 	struct usb4_port *usb4 = port->usb4;
783 	struct tb *tb = port->sw->tb;
784 
785 	if (mutex_lock_interruptible(&tb->lock))
786 		return -ERESTARTSYS;
787 
788 	if (supports_time(usb4)) {
789 		if (usb4->margining->time)
790 			seq_puts(s, "voltage [time]\n");
791 		else
792 			seq_puts(s, "[voltage] time\n");
793 	} else {
794 		seq_puts(s, "[voltage]\n");
795 	}
796 
797 	mutex_unlock(&tb->lock);
798 	return 0;
799 }
800 DEBUGFS_ATTR_RW(margining_test);
801 
802 static ssize_t margining_margin_write(struct file *file,
803 				    const char __user *user_buf,
804 				    size_t count, loff_t *ppos)
805 {
806 	struct seq_file *s = file->private_data;
807 	struct tb_port *port = s->private;
808 	struct usb4_port *usb4 = port->usb4;
809 	struct tb *tb = port->sw->tb;
810 	int ret = 0;
811 	char *buf;
812 
813 	buf = validate_and_copy_from_user(user_buf, &count);
814 	if (IS_ERR(buf))
815 		return PTR_ERR(buf);
816 
817 	buf[count - 1] = '\0';
818 
819 	if (mutex_lock_interruptible(&tb->lock)) {
820 		ret = -ERESTARTSYS;
821 		goto out_free;
822 	}
823 
824 	if (usb4->margining->time) {
825 		if (!strcmp(buf, "left"))
826 			usb4->margining->right_high = false;
827 		else if (!strcmp(buf, "right"))
828 			usb4->margining->right_high = true;
829 		else
830 			ret = -EINVAL;
831 	} else {
832 		if (!strcmp(buf, "low"))
833 			usb4->margining->right_high = false;
834 		else if (!strcmp(buf, "high"))
835 			usb4->margining->right_high = true;
836 		else
837 			ret = -EINVAL;
838 	}
839 
840 	mutex_unlock(&tb->lock);
841 
842 out_free:
843 	free_page((unsigned long)buf);
844 	return ret ? ret : count;
845 }
846 
847 static int margining_margin_show(struct seq_file *s, void *not_used)
848 {
849 	struct tb_port *port = s->private;
850 	struct usb4_port *usb4 = port->usb4;
851 	struct tb *tb = port->sw->tb;
852 
853 	if (mutex_lock_interruptible(&tb->lock))
854 		return -ERESTARTSYS;
855 
856 	if (usb4->margining->time) {
857 		if (usb4->margining->right_high)
858 			seq_puts(s, "left [right]\n");
859 		else
860 			seq_puts(s, "[left] right\n");
861 	} else {
862 		if (usb4->margining->right_high)
863 			seq_puts(s, "low [high]\n");
864 		else
865 			seq_puts(s, "[low] high\n");
866 	}
867 
868 	mutex_unlock(&tb->lock);
869 	return 0;
870 }
871 DEBUGFS_ATTR_RW(margining_margin);
872 
873 static void margining_port_init(struct tb_port *port)
874 {
875 	struct tb_margining *margining;
876 	struct dentry *dir, *parent;
877 	struct usb4_port *usb4;
878 	char dir_name[10];
879 	unsigned int val;
880 	int ret;
881 
882 	usb4 = port->usb4;
883 	if (!usb4)
884 		return;
885 
886 	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
887 	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
888 
889 	margining = kzalloc(sizeof(*margining), GFP_KERNEL);
890 	if (!margining)
891 		return;
892 
893 	ret = usb4_port_margining_caps(port, margining->caps);
894 	if (ret) {
895 		kfree(margining);
896 		return;
897 	}
898 
899 	usb4->margining = margining;
900 
901 	/* Set the initial mode */
902 	if (supports_software(usb4))
903 		margining->software = true;
904 
905 	val = (margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_STEPS_MASK) >>
906 		USB4_MARGIN_CAP_0_VOLTAGE_STEPS_SHIFT;
907 	margining->voltage_steps = val;
908 	val = (margining->caps[0] & USB4_MARGIN_CAP_0_MAX_VOLTAGE_OFFSET_MASK) >>
909 		USB4_MARGIN_CAP_0_MAX_VOLTAGE_OFFSET_SHIFT;
910 	margining->max_voltage_offset = 74 + val * 2;
911 
912 	if (supports_time(usb4)) {
913 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_TIME_STEPS_MASK) >>
914 			USB4_MARGIN_CAP_1_TIME_STEPS_SHIFT;
915 		margining->time_steps = val;
916 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_TIME_OFFSET_MASK) >>
917 			USB4_MARGIN_CAP_1_TIME_OFFSET_SHIFT;
918 		/*
919 		 * Store it as mUI (milli Unit Interval) because we want
920 		 * to keep it as integer.
921 		 */
922 		margining->max_time_offset = 200 + 10 * val;
923 	}
924 
925 	dir = debugfs_create_dir("margining", parent);
926 	if (supports_hardware(usb4)) {
927 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_MIN_BER_MASK) >>
928 			USB4_MARGIN_CAP_1_MIN_BER_SHIFT;
929 		margining->min_ber_level = val;
930 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_MAX_BER_MASK) >>
931 			USB4_MARGIN_CAP_1_MAX_BER_SHIFT;
932 		margining->max_ber_level = val;
933 
934 		/* Set the default to minimum */
935 		margining->ber_level = margining->min_ber_level;
936 
937 		debugfs_create_file("ber_level_contour", 0400, dir, port,
938 				    &margining_ber_level_fops);
939 	}
940 	debugfs_create_file("caps", 0400, dir, port, &margining_caps_fops);
941 	debugfs_create_file("lanes", 0600, dir, port, &margining_lanes_fops);
942 	debugfs_create_file("mode", 0600, dir, port, &margining_mode_fops);
943 	debugfs_create_file("run", 0600, dir, port, &margining_run_fops);
944 	debugfs_create_file("results", 0600, dir, port, &margining_results_fops);
945 	debugfs_create_file("test", 0600, dir, port, &margining_test_fops);
946 	if (independent_voltage_margins(usb4) ||
947 	    (supports_time(usb4) && independent_time_margins(usb4)))
948 		debugfs_create_file("margin", 0600, dir, port, &margining_margin_fops);
949 }
950 
951 static void margining_port_remove(struct tb_port *port)
952 {
953 	struct dentry *parent;
954 	char dir_name[10];
955 
956 	if (!port->usb4)
957 		return;
958 
959 	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
960 	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
961 	if (parent)
962 		debugfs_lookup_and_remove("margining", parent);
963 
964 	kfree(port->usb4->margining);
965 	port->usb4->margining = NULL;
966 }
967 
968 static void margining_switch_init(struct tb_switch *sw)
969 {
970 	struct tb_port *upstream, *downstream;
971 	struct tb_switch *parent_sw;
972 	u64 route = tb_route(sw);
973 
974 	if (!route)
975 		return;
976 
977 	upstream = tb_upstream_port(sw);
978 	parent_sw = tb_switch_parent(sw);
979 	downstream = tb_port_at(route, parent_sw);
980 
981 	margining_port_init(downstream);
982 	margining_port_init(upstream);
983 }
984 
985 static void margining_switch_remove(struct tb_switch *sw)
986 {
987 	struct tb_port *upstream, *downstream;
988 	struct tb_switch *parent_sw;
989 	u64 route = tb_route(sw);
990 
991 	if (!route)
992 		return;
993 
994 	upstream = tb_upstream_port(sw);
995 	parent_sw = tb_switch_parent(sw);
996 	downstream = tb_port_at(route, parent_sw);
997 
998 	margining_port_remove(upstream);
999 	margining_port_remove(downstream);
1000 }
1001 
1002 static void margining_xdomain_init(struct tb_xdomain *xd)
1003 {
1004 	struct tb_switch *parent_sw;
1005 	struct tb_port *downstream;
1006 
1007 	parent_sw = tb_xdomain_parent(xd);
1008 	downstream = tb_port_at(xd->route, parent_sw);
1009 
1010 	margining_port_init(downstream);
1011 }
1012 
1013 static void margining_xdomain_remove(struct tb_xdomain *xd)
1014 {
1015 	struct tb_switch *parent_sw;
1016 	struct tb_port *downstream;
1017 
1018 	parent_sw = tb_xdomain_parent(xd);
1019 	downstream = tb_port_at(xd->route, parent_sw);
1020 	margining_port_remove(downstream);
1021 }
1022 #else
1023 static inline void margining_switch_init(struct tb_switch *sw) { }
1024 static inline void margining_switch_remove(struct tb_switch *sw) { }
1025 static inline void margining_xdomain_init(struct tb_xdomain *xd) { }
1026 static inline void margining_xdomain_remove(struct tb_xdomain *xd) { }
1027 #endif
1028 
1029 static int port_clear_all_counters(struct tb_port *port)
1030 {
1031 	u32 *buf;
1032 	int ret;
1033 
1034 	buf = kcalloc(COUNTER_SET_LEN * port->config.max_counters, sizeof(u32),
1035 		      GFP_KERNEL);
1036 	if (!buf)
1037 		return -ENOMEM;
1038 
1039 	ret = tb_port_write(port, buf, TB_CFG_COUNTERS, 0,
1040 			    COUNTER_SET_LEN * port->config.max_counters);
1041 	kfree(buf);
1042 
1043 	return ret;
1044 }
1045 
1046 static ssize_t counters_write(struct file *file, const char __user *user_buf,
1047 			      size_t count, loff_t *ppos)
1048 {
1049 	struct seq_file *s = file->private_data;
1050 	struct tb_port *port = s->private;
1051 	struct tb_switch *sw = port->sw;
1052 	struct tb *tb = port->sw->tb;
1053 	char *buf;
1054 	int ret;
1055 
1056 	buf = validate_and_copy_from_user(user_buf, &count);
1057 	if (IS_ERR(buf))
1058 		return PTR_ERR(buf);
1059 
1060 	pm_runtime_get_sync(&sw->dev);
1061 
1062 	if (mutex_lock_interruptible(&tb->lock)) {
1063 		ret = -ERESTARTSYS;
1064 		goto out;
1065 	}
1066 
1067 	/* If written delimiter only, clear all counters in one shot */
1068 	if (buf[0] == '\n') {
1069 		ret = port_clear_all_counters(port);
1070 	} else  {
1071 		char *line = buf;
1072 		u32 val, offset;
1073 
1074 		ret = -EINVAL;
1075 		while (parse_line(&line, &offset, &val, 1, 4)) {
1076 			ret = tb_port_write(port, &val, TB_CFG_COUNTERS,
1077 					    offset, 1);
1078 			if (ret)
1079 				break;
1080 		}
1081 	}
1082 
1083 	mutex_unlock(&tb->lock);
1084 
1085 out:
1086 	pm_runtime_mark_last_busy(&sw->dev);
1087 	pm_runtime_put_autosuspend(&sw->dev);
1088 	free_page((unsigned long)buf);
1089 
1090 	return ret < 0 ? ret : count;
1091 }
1092 
1093 static void cap_show_by_dw(struct seq_file *s, struct tb_switch *sw,
1094 			   struct tb_port *port, unsigned int cap,
1095 			   unsigned int offset, u8 cap_id, u8 vsec_id,
1096 			   int dwords)
1097 {
1098 	int i, ret;
1099 	u32 data;
1100 
1101 	for (i = 0; i < dwords; i++) {
1102 		if (port)
1103 			ret = tb_port_read(port, &data, TB_CFG_PORT, cap + offset + i, 1);
1104 		else
1105 			ret = tb_sw_read(sw, &data, TB_CFG_SWITCH, cap + offset + i, 1);
1106 		if (ret) {
1107 			seq_printf(s, "0x%04x <not accessible>\n", cap + offset + i);
1108 			continue;
1109 		}
1110 
1111 		seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n", cap + offset + i,
1112 			   offset + i, cap_id, vsec_id, data);
1113 	}
1114 }
1115 
1116 static void cap_show(struct seq_file *s, struct tb_switch *sw,
1117 		     struct tb_port *port, unsigned int cap, u8 cap_id,
1118 		     u8 vsec_id, int length)
1119 {
1120 	int ret, offset = 0;
1121 
1122 	while (length > 0) {
1123 		int i, dwords = min(length, TB_MAX_CONFIG_RW_LENGTH);
1124 		u32 data[TB_MAX_CONFIG_RW_LENGTH];
1125 
1126 		if (port)
1127 			ret = tb_port_read(port, data, TB_CFG_PORT, cap + offset,
1128 					   dwords);
1129 		else
1130 			ret = tb_sw_read(sw, data, TB_CFG_SWITCH, cap + offset, dwords);
1131 		if (ret) {
1132 			cap_show_by_dw(s, sw, port, cap, offset, cap_id, vsec_id, length);
1133 			return;
1134 		}
1135 
1136 		for (i = 0; i < dwords; i++) {
1137 			seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n",
1138 				   cap + offset + i, offset + i,
1139 				   cap_id, vsec_id, data[i]);
1140 		}
1141 
1142 		length -= dwords;
1143 		offset += dwords;
1144 	}
1145 }
1146 
1147 static void port_cap_show(struct tb_port *port, struct seq_file *s,
1148 			  unsigned int cap)
1149 {
1150 	struct tb_cap_any header;
1151 	u8 vsec_id = 0;
1152 	size_t length;
1153 	int ret;
1154 
1155 	ret = tb_port_read(port, &header, TB_CFG_PORT, cap, 1);
1156 	if (ret) {
1157 		seq_printf(s, "0x%04x <capability read failed>\n", cap);
1158 		return;
1159 	}
1160 
1161 	switch (header.basic.cap) {
1162 	case TB_PORT_CAP_PHY:
1163 		length = PORT_CAP_LANE_LEN;
1164 		break;
1165 
1166 	case TB_PORT_CAP_TIME1:
1167 		if (usb4_switch_version(port->sw) < 2)
1168 			length = PORT_CAP_TMU_V1_LEN;
1169 		else
1170 			length = PORT_CAP_TMU_V2_LEN;
1171 		break;
1172 
1173 	case TB_PORT_CAP_POWER:
1174 		length = PORT_CAP_POWER_LEN;
1175 		break;
1176 
1177 	case TB_PORT_CAP_ADAP:
1178 		if (tb_port_is_pcie_down(port) || tb_port_is_pcie_up(port)) {
1179 			if (usb4_switch_version(port->sw) < 2)
1180 				length = PORT_CAP_V1_PCIE_LEN;
1181 			else
1182 				length = PORT_CAP_V2_PCIE_LEN;
1183 		} else if (tb_port_is_dpin(port)) {
1184 			if (usb4_switch_version(port->sw) < 2)
1185 				length = PORT_CAP_DP_V1_LEN;
1186 			else
1187 				length = PORT_CAP_DP_V2_LEN;
1188 		} else if (tb_port_is_dpout(port)) {
1189 			length = PORT_CAP_DP_V1_LEN;
1190 		} else if (tb_port_is_usb3_down(port) ||
1191 			   tb_port_is_usb3_up(port)) {
1192 			length = PORT_CAP_USB3_LEN;
1193 		} else {
1194 			seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
1195 				   cap, header.basic.cap);
1196 			return;
1197 		}
1198 		break;
1199 
1200 	case TB_PORT_CAP_VSE:
1201 		if (!header.extended_short.length) {
1202 			ret = tb_port_read(port, (u32 *)&header + 1, TB_CFG_PORT,
1203 					   cap + 1, 1);
1204 			if (ret) {
1205 				seq_printf(s, "0x%04x <capability read failed>\n",
1206 					   cap + 1);
1207 				return;
1208 			}
1209 			length = header.extended_long.length;
1210 			vsec_id = header.extended_short.vsec_id;
1211 		} else {
1212 			length = header.extended_short.length;
1213 			vsec_id = header.extended_short.vsec_id;
1214 		}
1215 		break;
1216 
1217 	case TB_PORT_CAP_USB4:
1218 		length = PORT_CAP_USB4_LEN;
1219 		break;
1220 
1221 	default:
1222 		seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
1223 			   cap, header.basic.cap);
1224 		return;
1225 	}
1226 
1227 	cap_show(s, NULL, port, cap, header.basic.cap, vsec_id, length);
1228 }
1229 
1230 static void port_caps_show(struct tb_port *port, struct seq_file *s)
1231 {
1232 	int cap;
1233 
1234 	cap = tb_port_next_cap(port, 0);
1235 	while (cap > 0) {
1236 		port_cap_show(port, s, cap);
1237 		cap = tb_port_next_cap(port, cap);
1238 	}
1239 }
1240 
1241 static int port_basic_regs_show(struct tb_port *port, struct seq_file *s)
1242 {
1243 	u32 data[PORT_CAP_BASIC_LEN];
1244 	int ret, i;
1245 
1246 	ret = tb_port_read(port, data, TB_CFG_PORT, 0, ARRAY_SIZE(data));
1247 	if (ret)
1248 		return ret;
1249 
1250 	for (i = 0; i < ARRAY_SIZE(data); i++)
1251 		seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
1252 
1253 	return 0;
1254 }
1255 
1256 static int port_regs_show(struct seq_file *s, void *not_used)
1257 {
1258 	struct tb_port *port = s->private;
1259 	struct tb_switch *sw = port->sw;
1260 	struct tb *tb = sw->tb;
1261 	int ret;
1262 
1263 	pm_runtime_get_sync(&sw->dev);
1264 
1265 	if (mutex_lock_interruptible(&tb->lock)) {
1266 		ret = -ERESTARTSYS;
1267 		goto out_rpm_put;
1268 	}
1269 
1270 	seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
1271 
1272 	ret = port_basic_regs_show(port, s);
1273 	if (ret)
1274 		goto out_unlock;
1275 
1276 	port_caps_show(port, s);
1277 
1278 out_unlock:
1279 	mutex_unlock(&tb->lock);
1280 out_rpm_put:
1281 	pm_runtime_mark_last_busy(&sw->dev);
1282 	pm_runtime_put_autosuspend(&sw->dev);
1283 
1284 	return ret;
1285 }
1286 DEBUGFS_ATTR_RW(port_regs);
1287 
1288 static void switch_cap_show(struct tb_switch *sw, struct seq_file *s,
1289 			    unsigned int cap)
1290 {
1291 	struct tb_cap_any header;
1292 	int ret, length;
1293 	u8 vsec_id = 0;
1294 
1295 	ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, cap, 1);
1296 	if (ret) {
1297 		seq_printf(s, "0x%04x <capability read failed>\n", cap);
1298 		return;
1299 	}
1300 
1301 	if (header.basic.cap == TB_SWITCH_CAP_VSE) {
1302 		if (!header.extended_short.length) {
1303 			ret = tb_sw_read(sw, (u32 *)&header + 1, TB_CFG_SWITCH,
1304 					 cap + 1, 1);
1305 			if (ret) {
1306 				seq_printf(s, "0x%04x <capability read failed>\n",
1307 					   cap + 1);
1308 				return;
1309 			}
1310 			length = header.extended_long.length;
1311 		} else {
1312 			length = header.extended_short.length;
1313 		}
1314 		vsec_id = header.extended_short.vsec_id;
1315 	} else {
1316 		if (header.basic.cap == TB_SWITCH_CAP_TMU) {
1317 			length = SWITCH_CAP_TMU_LEN;
1318 		} else  {
1319 			seq_printf(s, "0x%04x <unknown capability 0x%02x>\n",
1320 				   cap, header.basic.cap);
1321 			return;
1322 		}
1323 	}
1324 
1325 	cap_show(s, sw, NULL, cap, header.basic.cap, vsec_id, length);
1326 }
1327 
1328 static void switch_caps_show(struct tb_switch *sw, struct seq_file *s)
1329 {
1330 	int cap;
1331 
1332 	cap = tb_switch_next_cap(sw, 0);
1333 	while (cap > 0) {
1334 		switch_cap_show(sw, s, cap);
1335 		cap = tb_switch_next_cap(sw, cap);
1336 	}
1337 }
1338 
1339 static int switch_basic_regs_show(struct tb_switch *sw, struct seq_file *s)
1340 {
1341 	u32 data[SWITCH_CAP_BASIC_LEN];
1342 	size_t dwords;
1343 	int ret, i;
1344 
1345 	/* Only USB4 has the additional registers */
1346 	if (tb_switch_is_usb4(sw))
1347 		dwords = ARRAY_SIZE(data);
1348 	else
1349 		dwords = 7;
1350 
1351 	ret = tb_sw_read(sw, data, TB_CFG_SWITCH, 0, dwords);
1352 	if (ret)
1353 		return ret;
1354 
1355 	for (i = 0; i < dwords; i++)
1356 		seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
1357 
1358 	return 0;
1359 }
1360 
1361 static int switch_regs_show(struct seq_file *s, void *not_used)
1362 {
1363 	struct tb_switch *sw = s->private;
1364 	struct tb *tb = sw->tb;
1365 	int ret;
1366 
1367 	pm_runtime_get_sync(&sw->dev);
1368 
1369 	if (mutex_lock_interruptible(&tb->lock)) {
1370 		ret = -ERESTARTSYS;
1371 		goto out_rpm_put;
1372 	}
1373 
1374 	seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
1375 
1376 	ret = switch_basic_regs_show(sw, s);
1377 	if (ret)
1378 		goto out_unlock;
1379 
1380 	switch_caps_show(sw, s);
1381 
1382 out_unlock:
1383 	mutex_unlock(&tb->lock);
1384 out_rpm_put:
1385 	pm_runtime_mark_last_busy(&sw->dev);
1386 	pm_runtime_put_autosuspend(&sw->dev);
1387 
1388 	return ret;
1389 }
1390 DEBUGFS_ATTR_RW(switch_regs);
1391 
1392 static int path_show_one(struct tb_port *port, struct seq_file *s, int hopid)
1393 {
1394 	u32 data[PATH_LEN];
1395 	int ret, i;
1396 
1397 	ret = tb_port_read(port, data, TB_CFG_HOPS, hopid * PATH_LEN,
1398 			   ARRAY_SIZE(data));
1399 	if (ret) {
1400 		seq_printf(s, "0x%04x <not accessible>\n", hopid * PATH_LEN);
1401 		return ret;
1402 	}
1403 
1404 	for (i = 0; i < ARRAY_SIZE(data); i++) {
1405 		seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
1406 			   hopid * PATH_LEN + i, i, hopid, data[i]);
1407 	}
1408 
1409 	return 0;
1410 }
1411 
1412 static int path_show(struct seq_file *s, void *not_used)
1413 {
1414 	struct tb_port *port = s->private;
1415 	struct tb_switch *sw = port->sw;
1416 	struct tb *tb = sw->tb;
1417 	int start, i, ret = 0;
1418 
1419 	pm_runtime_get_sync(&sw->dev);
1420 
1421 	if (mutex_lock_interruptible(&tb->lock)) {
1422 		ret = -ERESTARTSYS;
1423 		goto out_rpm_put;
1424 	}
1425 
1426 	seq_puts(s, "# offset relative_offset in_hop_id value\n");
1427 
1428 	/* NHI and lane adapters have entry for path 0 */
1429 	if (tb_port_is_null(port) || tb_port_is_nhi(port)) {
1430 		ret = path_show_one(port, s, 0);
1431 		if (ret)
1432 			goto out_unlock;
1433 	}
1434 
1435 	start = tb_port_is_nhi(port) ? 1 : TB_PATH_MIN_HOPID;
1436 
1437 	for (i = start; i <= port->config.max_in_hop_id; i++) {
1438 		ret = path_show_one(port, s, i);
1439 		if (ret)
1440 			break;
1441 	}
1442 
1443 out_unlock:
1444 	mutex_unlock(&tb->lock);
1445 out_rpm_put:
1446 	pm_runtime_mark_last_busy(&sw->dev);
1447 	pm_runtime_put_autosuspend(&sw->dev);
1448 
1449 	return ret;
1450 }
1451 DEBUGFS_ATTR_RO(path);
1452 
1453 static int counter_set_regs_show(struct tb_port *port, struct seq_file *s,
1454 				 int counter)
1455 {
1456 	u32 data[COUNTER_SET_LEN];
1457 	int ret, i;
1458 
1459 	ret = tb_port_read(port, data, TB_CFG_COUNTERS,
1460 			   counter * COUNTER_SET_LEN, ARRAY_SIZE(data));
1461 	if (ret) {
1462 		seq_printf(s, "0x%04x <not accessible>\n",
1463 			   counter * COUNTER_SET_LEN);
1464 		return ret;
1465 	}
1466 
1467 	for (i = 0; i < ARRAY_SIZE(data); i++) {
1468 		seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
1469 			   counter * COUNTER_SET_LEN + i, i, counter, data[i]);
1470 	}
1471 
1472 	return 0;
1473 }
1474 
1475 static int counters_show(struct seq_file *s, void *not_used)
1476 {
1477 	struct tb_port *port = s->private;
1478 	struct tb_switch *sw = port->sw;
1479 	struct tb *tb = sw->tb;
1480 	int i, ret = 0;
1481 
1482 	pm_runtime_get_sync(&sw->dev);
1483 
1484 	if (mutex_lock_interruptible(&tb->lock)) {
1485 		ret = -ERESTARTSYS;
1486 		goto out;
1487 	}
1488 
1489 	seq_puts(s, "# offset relative_offset counter_id value\n");
1490 
1491 	for (i = 0; i < port->config.max_counters; i++) {
1492 		ret = counter_set_regs_show(port, s, i);
1493 		if (ret)
1494 			break;
1495 	}
1496 
1497 	mutex_unlock(&tb->lock);
1498 
1499 out:
1500 	pm_runtime_mark_last_busy(&sw->dev);
1501 	pm_runtime_put_autosuspend(&sw->dev);
1502 
1503 	return ret;
1504 }
1505 DEBUGFS_ATTR_RW(counters);
1506 
1507 /**
1508  * tb_switch_debugfs_init() - Add debugfs entries for router
1509  * @sw: Pointer to the router
1510  *
1511  * Adds debugfs directories and files for given router.
1512  */
1513 void tb_switch_debugfs_init(struct tb_switch *sw)
1514 {
1515 	struct dentry *debugfs_dir;
1516 	struct tb_port *port;
1517 
1518 	debugfs_dir = debugfs_create_dir(dev_name(&sw->dev), tb_debugfs_root);
1519 	sw->debugfs_dir = debugfs_dir;
1520 	debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir, sw,
1521 			    &switch_regs_fops);
1522 
1523 	tb_switch_for_each_port(sw, port) {
1524 		struct dentry *debugfs_dir;
1525 		char dir_name[10];
1526 
1527 		if (port->disabled)
1528 			continue;
1529 		if (port->config.type == TB_TYPE_INACTIVE)
1530 			continue;
1531 
1532 		snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
1533 		debugfs_dir = debugfs_create_dir(dir_name, sw->debugfs_dir);
1534 		debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir,
1535 				    port, &port_regs_fops);
1536 		debugfs_create_file("path", 0400, debugfs_dir, port,
1537 				    &path_fops);
1538 		if (port->config.counters_support)
1539 			debugfs_create_file("counters", 0600, debugfs_dir, port,
1540 					    &counters_fops);
1541 	}
1542 
1543 	margining_switch_init(sw);
1544 }
1545 
1546 /**
1547  * tb_switch_debugfs_remove() - Remove all router debugfs entries
1548  * @sw: Pointer to the router
1549  *
1550  * Removes all previously added debugfs entries under this router.
1551  */
1552 void tb_switch_debugfs_remove(struct tb_switch *sw)
1553 {
1554 	margining_switch_remove(sw);
1555 	debugfs_remove_recursive(sw->debugfs_dir);
1556 }
1557 
1558 void tb_xdomain_debugfs_init(struct tb_xdomain *xd)
1559 {
1560 	margining_xdomain_init(xd);
1561 }
1562 
1563 void tb_xdomain_debugfs_remove(struct tb_xdomain *xd)
1564 {
1565 	margining_xdomain_remove(xd);
1566 }
1567 
1568 /**
1569  * tb_service_debugfs_init() - Add debugfs directory for service
1570  * @svc: Thunderbolt service pointer
1571  *
1572  * Adds debugfs directory for service.
1573  */
1574 void tb_service_debugfs_init(struct tb_service *svc)
1575 {
1576 	svc->debugfs_dir = debugfs_create_dir(dev_name(&svc->dev),
1577 					      tb_debugfs_root);
1578 }
1579 
1580 /**
1581  * tb_service_debugfs_remove() - Remove service debugfs directory
1582  * @svc: Thunderbolt service pointer
1583  *
1584  * Removes the previously created debugfs directory for @svc.
1585  */
1586 void tb_service_debugfs_remove(struct tb_service *svc)
1587 {
1588 	debugfs_remove_recursive(svc->debugfs_dir);
1589 	svc->debugfs_dir = NULL;
1590 }
1591 
1592 void tb_debugfs_init(void)
1593 {
1594 	tb_debugfs_root = debugfs_create_dir("thunderbolt", NULL);
1595 }
1596 
1597 void tb_debugfs_exit(void)
1598 {
1599 	debugfs_remove_recursive(tb_debugfs_root);
1600 }
1601