xref: /linux/drivers/thunderbolt/debugfs.c (revision 69bfec7548f4c1595bac0e3ddfc0458a5af31f4c)
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_PCIE_LEN	1
18 #define PORT_CAP_POWER_LEN	2
19 #define PORT_CAP_LANE_LEN	3
20 #define PORT_CAP_USB3_LEN	5
21 #define PORT_CAP_DP_LEN		8
22 #define PORT_CAP_TMU_LEN	8
23 #define PORT_CAP_BASIC_LEN	9
24 #define PORT_CAP_USB4_LEN	20
25 
26 #define SWITCH_CAP_TMU_LEN	26
27 #define SWITCH_CAP_BASIC_LEN	27
28 
29 #define PATH_LEN		2
30 
31 #define COUNTER_SET_LEN		3
32 
33 #define DEBUGFS_ATTR(__space, __write)					\
34 static int __space ## _open(struct inode *inode, struct file *file)	\
35 {									\
36 	return single_open(file, __space ## _show, inode->i_private);	\
37 }									\
38 									\
39 static const struct file_operations __space ## _fops = {		\
40 	.owner = THIS_MODULE,						\
41 	.open = __space ## _open,					\
42 	.release = single_release,					\
43 	.read  = seq_read,						\
44 	.write = __write,						\
45 	.llseek = seq_lseek,						\
46 }
47 
48 #define DEBUGFS_ATTR_RO(__space)					\
49 	DEBUGFS_ATTR(__space, NULL)
50 
51 #define DEBUGFS_ATTR_RW(__space)					\
52 	DEBUGFS_ATTR(__space, __space ## _write)
53 
54 static struct dentry *tb_debugfs_root;
55 
56 static void *validate_and_copy_from_user(const void __user *user_buf,
57 					 size_t *count)
58 {
59 	size_t nbytes;
60 	void *buf;
61 
62 	if (!*count)
63 		return ERR_PTR(-EINVAL);
64 
65 	if (!access_ok(user_buf, *count))
66 		return ERR_PTR(-EFAULT);
67 
68 	buf = (void *)get_zeroed_page(GFP_KERNEL);
69 	if (!buf)
70 		return ERR_PTR(-ENOMEM);
71 
72 	nbytes = min_t(size_t, *count, PAGE_SIZE);
73 	if (copy_from_user(buf, user_buf, nbytes)) {
74 		free_page((unsigned long)buf);
75 		return ERR_PTR(-EFAULT);
76 	}
77 
78 	*count = nbytes;
79 	return buf;
80 }
81 
82 static bool parse_line(char **line, u32 *offs, u32 *val, int short_fmt_len,
83 		       int long_fmt_len)
84 {
85 	char *token;
86 	u32 v[5];
87 	int ret;
88 
89 	token = strsep(line, "\n");
90 	if (!token)
91 		return false;
92 
93 	/*
94 	 * For Adapter/Router configuration space:
95 	 * Short format is: offset value\n
96 	 *		    v[0]   v[1]
97 	 * Long format as produced from the read side:
98 	 * offset relative_offset cap_id vs_cap_id value\n
99 	 * v[0]   v[1]            v[2]   v[3]      v[4]
100 	 *
101 	 * For Counter configuration space:
102 	 * Short format is: offset\n
103 	 *		    v[0]
104 	 * Long format as produced from the read side:
105 	 * offset relative_offset counter_id value\n
106 	 * v[0]   v[1]            v[2]       v[3]
107 	 */
108 	ret = sscanf(token, "%i %i %i %i %i", &v[0], &v[1], &v[2], &v[3], &v[4]);
109 	/* In case of Counters, clear counter, "val" content is NA */
110 	if (ret == short_fmt_len) {
111 		*offs = v[0];
112 		*val = v[short_fmt_len - 1];
113 		return true;
114 	} else if (ret == long_fmt_len) {
115 		*offs = v[0];
116 		*val = v[long_fmt_len - 1];
117 		return true;
118 	}
119 
120 	return false;
121 }
122 
123 #if IS_ENABLED(CONFIG_USB4_DEBUGFS_WRITE)
124 static ssize_t regs_write(struct tb_switch *sw, struct tb_port *port,
125 			  const char __user *user_buf, size_t count,
126 			  loff_t *ppos)
127 {
128 	struct tb *tb = sw->tb;
129 	char *line, *buf;
130 	u32 val, offset;
131 	int ret = 0;
132 
133 	buf = validate_and_copy_from_user(user_buf, &count);
134 	if (IS_ERR(buf))
135 		return PTR_ERR(buf);
136 
137 	pm_runtime_get_sync(&sw->dev);
138 
139 	if (mutex_lock_interruptible(&tb->lock)) {
140 		ret = -ERESTARTSYS;
141 		goto out;
142 	}
143 
144 	/* User did hardware changes behind the driver's back */
145 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
146 
147 	line = buf;
148 	while (parse_line(&line, &offset, &val, 2, 5)) {
149 		if (port)
150 			ret = tb_port_write(port, &val, TB_CFG_PORT, offset, 1);
151 		else
152 			ret = tb_sw_write(sw, &val, TB_CFG_SWITCH, offset, 1);
153 		if (ret)
154 			break;
155 	}
156 
157 	mutex_unlock(&tb->lock);
158 
159 out:
160 	pm_runtime_mark_last_busy(&sw->dev);
161 	pm_runtime_put_autosuspend(&sw->dev);
162 	free_page((unsigned long)buf);
163 
164 	return ret < 0 ? ret : count;
165 }
166 
167 static ssize_t port_regs_write(struct file *file, const char __user *user_buf,
168 			       size_t count, loff_t *ppos)
169 {
170 	struct seq_file *s = file->private_data;
171 	struct tb_port *port = s->private;
172 
173 	return regs_write(port->sw, port, user_buf, count, ppos);
174 }
175 
176 static ssize_t switch_regs_write(struct file *file, const char __user *user_buf,
177 				 size_t count, loff_t *ppos)
178 {
179 	struct seq_file *s = file->private_data;
180 	struct tb_switch *sw = s->private;
181 
182 	return regs_write(sw, NULL, user_buf, count, ppos);
183 }
184 #define DEBUGFS_MODE		0600
185 #else
186 #define port_regs_write		NULL
187 #define switch_regs_write	NULL
188 #define DEBUGFS_MODE		0400
189 #endif
190 
191 #if IS_ENABLED(CONFIG_USB4_DEBUGFS_MARGINING)
192 /**
193  * struct tb_margining - Lane margining support
194  * @caps: Port lane margining capabilities
195  * @results: Last lane margining results
196  * @lanes: %0, %1 or %7 (all)
197  * @min_ber_level: Minimum supported BER level contour value
198  * @max_ber_level: Maximum supported BER level contour value
199  * @ber_level: Current BER level contour value
200  * @voltage_steps: Number of mandatory voltage steps
201  * @max_voltage_offset: Maximum mandatory voltage offset (in mV)
202  * @time_steps: Number of time margin steps
203  * @max_time_offset: Maximum time margin offset (in mUI)
204  * @software: %true if software margining is used instead of hardware
205  * @time: %true if time margining is used instead of voltage
206  * @right_high: %false if left/low margin test is performed, %true if
207  *		right/high
208  */
209 struct tb_margining {
210 	u32 caps[2];
211 	u32 results[2];
212 	unsigned int lanes;
213 	unsigned int min_ber_level;
214 	unsigned int max_ber_level;
215 	unsigned int ber_level;
216 	unsigned int voltage_steps;
217 	unsigned int max_voltage_offset;
218 	unsigned int time_steps;
219 	unsigned int max_time_offset;
220 	bool software;
221 	bool time;
222 	bool right_high;
223 };
224 
225 static bool supports_software(const struct usb4_port *usb4)
226 {
227 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_SW;
228 }
229 
230 static bool supports_hardware(const struct usb4_port *usb4)
231 {
232 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_HW;
233 }
234 
235 static bool both_lanes(const struct usb4_port *usb4)
236 {
237 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_2_LANES;
238 }
239 
240 static unsigned int independent_voltage_margins(const struct usb4_port *usb4)
241 {
242 	return (usb4->margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_INDP_MASK) >>
243 		USB4_MARGIN_CAP_0_VOLTAGE_INDP_SHIFT;
244 }
245 
246 static bool supports_time(const struct usb4_port *usb4)
247 {
248 	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_TIME;
249 }
250 
251 /* Only applicable if supports_time() returns true */
252 static unsigned int independent_time_margins(const struct usb4_port *usb4)
253 {
254 	return (usb4->margining->caps[1] & USB4_MARGIN_CAP_1_TIME_INDP_MASK) >>
255 		USB4_MARGIN_CAP_1_TIME_INDP_SHIFT;
256 }
257 
258 static ssize_t
259 margining_ber_level_write(struct file *file, const char __user *user_buf,
260 			   size_t count, loff_t *ppos)
261 {
262 	struct seq_file *s = file->private_data;
263 	struct tb_port *port = s->private;
264 	struct usb4_port *usb4 = port->usb4;
265 	struct tb *tb = port->sw->tb;
266 	unsigned int val;
267 	int ret = 0;
268 	char *buf;
269 
270 	if (mutex_lock_interruptible(&tb->lock))
271 		return -ERESTARTSYS;
272 
273 	if (usb4->margining->software) {
274 		ret = -EINVAL;
275 		goto out_unlock;
276 	}
277 
278 	buf = validate_and_copy_from_user(user_buf, &count);
279 	if (IS_ERR(buf)) {
280 		ret = PTR_ERR(buf);
281 		goto out_unlock;
282 	}
283 
284 	buf[count - 1] = '\0';
285 
286 	ret = kstrtouint(buf, 10, &val);
287 	if (ret)
288 		goto out_free;
289 
290 	if (val < usb4->margining->min_ber_level ||
291 	    val > usb4->margining->max_ber_level) {
292 		ret = -EINVAL;
293 		goto out_free;
294 	}
295 
296 	usb4->margining->ber_level = val;
297 
298 out_free:
299 	free_page((unsigned long)buf);
300 out_unlock:
301 	mutex_unlock(&tb->lock);
302 
303 	return ret < 0 ? ret : count;
304 }
305 
306 static void ber_level_show(struct seq_file *s, unsigned int val)
307 {
308 	if (val % 2)
309 		seq_printf(s, "3 * 1e%d (%u)\n", -12 + (val + 1) / 2, val);
310 	else
311 		seq_printf(s, "1e%d (%u)\n", -12 + val / 2, val);
312 }
313 
314 static int margining_ber_level_show(struct seq_file *s, void *not_used)
315 {
316 	struct tb_port *port = s->private;
317 	struct usb4_port *usb4 = port->usb4;
318 
319 	if (usb4->margining->software)
320 		return -EINVAL;
321 	ber_level_show(s, usb4->margining->ber_level);
322 	return 0;
323 }
324 DEBUGFS_ATTR_RW(margining_ber_level);
325 
326 static int margining_caps_show(struct seq_file *s, void *not_used)
327 {
328 	struct tb_port *port = s->private;
329 	struct usb4_port *usb4 = port->usb4;
330 	struct tb *tb = port->sw->tb;
331 	u32 cap0, cap1;
332 
333 	if (mutex_lock_interruptible(&tb->lock))
334 		return -ERESTARTSYS;
335 
336 	/* Dump the raw caps first */
337 	cap0 = usb4->margining->caps[0];
338 	seq_printf(s, "0x%08x\n", cap0);
339 	cap1 = usb4->margining->caps[1];
340 	seq_printf(s, "0x%08x\n", cap1);
341 
342 	seq_printf(s, "# software margining: %s\n",
343 		   supports_software(usb4) ? "yes" : "no");
344 	if (supports_hardware(usb4)) {
345 		seq_puts(s, "# hardware margining: yes\n");
346 		seq_puts(s, "# minimum BER level contour: ");
347 		ber_level_show(s, usb4->margining->min_ber_level);
348 		seq_puts(s, "# maximum BER level contour: ");
349 		ber_level_show(s, usb4->margining->max_ber_level);
350 	} else {
351 		seq_puts(s, "# hardware margining: no\n");
352 	}
353 
354 	seq_printf(s, "# both lanes simultaneously: %s\n",
355 		  both_lanes(usb4) ? "yes" : "no");
356 	seq_printf(s, "# voltage margin steps: %u\n",
357 		   usb4->margining->voltage_steps);
358 	seq_printf(s, "# maximum voltage offset: %u mV\n",
359 		   usb4->margining->max_voltage_offset);
360 
361 	switch (independent_voltage_margins(usb4)) {
362 	case USB4_MARGIN_CAP_0_VOLTAGE_MIN:
363 		seq_puts(s, "# returns minimum between high and low voltage margins\n");
364 		break;
365 	case USB4_MARGIN_CAP_0_VOLTAGE_HL:
366 		seq_puts(s, "# returns high or low voltage margin\n");
367 		break;
368 	case USB4_MARGIN_CAP_0_VOLTAGE_BOTH:
369 		seq_puts(s, "# returns both high and low margins\n");
370 		break;
371 	}
372 
373 	if (supports_time(usb4)) {
374 		seq_puts(s, "# time margining: yes\n");
375 		seq_printf(s, "# time margining is destructive: %s\n",
376 			   cap1 & USB4_MARGIN_CAP_1_TIME_DESTR ? "yes" : "no");
377 
378 		switch (independent_time_margins(usb4)) {
379 		case USB4_MARGIN_CAP_1_TIME_MIN:
380 			seq_puts(s, "# returns minimum between left and right time margins\n");
381 			break;
382 		case USB4_MARGIN_CAP_1_TIME_LR:
383 			seq_puts(s, "# returns left or right margin\n");
384 			break;
385 		case USB4_MARGIN_CAP_1_TIME_BOTH:
386 			seq_puts(s, "# returns both left and right margins\n");
387 			break;
388 		}
389 
390 		seq_printf(s, "# time margin steps: %u\n",
391 			   usb4->margining->time_steps);
392 		seq_printf(s, "# maximum time offset: %u mUI\n",
393 			   usb4->margining->max_time_offset);
394 	} else {
395 		seq_puts(s, "# time margining: no\n");
396 	}
397 
398 	mutex_unlock(&tb->lock);
399 	return 0;
400 }
401 DEBUGFS_ATTR_RO(margining_caps);
402 
403 static ssize_t
404 margining_lanes_write(struct file *file, const char __user *user_buf,
405 		      size_t count, loff_t *ppos)
406 {
407 	struct seq_file *s = file->private_data;
408 	struct tb_port *port = s->private;
409 	struct usb4_port *usb4 = port->usb4;
410 	struct tb *tb = port->sw->tb;
411 	int ret = 0;
412 	char *buf;
413 
414 	buf = validate_and_copy_from_user(user_buf, &count);
415 	if (IS_ERR(buf))
416 		return PTR_ERR(buf);
417 
418 	buf[count - 1] = '\0';
419 
420 	if (mutex_lock_interruptible(&tb->lock)) {
421 		ret = -ERESTARTSYS;
422 		goto out_free;
423 	}
424 
425 	if (!strcmp(buf, "0")) {
426 		usb4->margining->lanes = 0;
427 	} else if (!strcmp(buf, "1")) {
428 		usb4->margining->lanes = 1;
429 	} else if (!strcmp(buf, "all")) {
430 		/* Needs to be supported */
431 		if (both_lanes(usb4))
432 			usb4->margining->lanes = 7;
433 		else
434 			ret = -EINVAL;
435 	} else {
436 		ret = -EINVAL;
437 	}
438 
439 	mutex_unlock(&tb->lock);
440 
441 out_free:
442 	free_page((unsigned long)buf);
443 	return ret < 0 ? ret : count;
444 }
445 
446 static int margining_lanes_show(struct seq_file *s, void *not_used)
447 {
448 	struct tb_port *port = s->private;
449 	struct usb4_port *usb4 = port->usb4;
450 	struct tb *tb = port->sw->tb;
451 	unsigned int lanes;
452 
453 	if (mutex_lock_interruptible(&tb->lock))
454 		return -ERESTARTSYS;
455 
456 	lanes = usb4->margining->lanes;
457 	if (both_lanes(usb4)) {
458 		if (!lanes)
459 			seq_puts(s, "[0] 1 all\n");
460 		else if (lanes == 1)
461 			seq_puts(s, "0 [1] all\n");
462 		else
463 			seq_puts(s, "0 1 [all]\n");
464 	} else {
465 		if (!lanes)
466 			seq_puts(s, "[0] 1\n");
467 		else
468 			seq_puts(s, "0 [1]\n");
469 	}
470 
471 	mutex_unlock(&tb->lock);
472 	return 0;
473 }
474 DEBUGFS_ATTR_RW(margining_lanes);
475 
476 static ssize_t margining_mode_write(struct file *file,
477 				   const char __user *user_buf,
478 				   size_t count, loff_t *ppos)
479 {
480 	struct seq_file *s = file->private_data;
481 	struct tb_port *port = s->private;
482 	struct usb4_port *usb4 = port->usb4;
483 	struct tb *tb = port->sw->tb;
484 	int ret = 0;
485 	char *buf;
486 
487 	buf = validate_and_copy_from_user(user_buf, &count);
488 	if (IS_ERR(buf))
489 		return PTR_ERR(buf);
490 
491 	buf[count - 1] = '\0';
492 
493 	if (mutex_lock_interruptible(&tb->lock)) {
494 		ret = -ERESTARTSYS;
495 		goto out_free;
496 	}
497 
498 	if (!strcmp(buf, "software")) {
499 		if (supports_software(usb4))
500 			usb4->margining->software = true;
501 		else
502 			ret = -EINVAL;
503 	} else if (!strcmp(buf, "hardware")) {
504 		if (supports_hardware(usb4))
505 			usb4->margining->software = false;
506 		else
507 			ret = -EINVAL;
508 	} else {
509 		ret = -EINVAL;
510 	}
511 
512 	mutex_unlock(&tb->lock);
513 
514 out_free:
515 	free_page((unsigned long)buf);
516 	return ret ? ret : count;
517 }
518 
519 static int margining_mode_show(struct seq_file *s, void *not_used)
520 {
521 	const struct tb_port *port = s->private;
522 	const struct usb4_port *usb4 = port->usb4;
523 	struct tb *tb = port->sw->tb;
524 	const char *space = "";
525 
526 	if (mutex_lock_interruptible(&tb->lock))
527 		return -ERESTARTSYS;
528 
529 	if (supports_software(usb4)) {
530 		if (usb4->margining->software)
531 			seq_puts(s, "[software]");
532 		else
533 			seq_puts(s, "software");
534 		space = " ";
535 	}
536 	if (supports_hardware(usb4)) {
537 		if (usb4->margining->software)
538 			seq_printf(s, "%shardware", space);
539 		else
540 			seq_printf(s, "%s[hardware]", space);
541 	}
542 
543 	mutex_unlock(&tb->lock);
544 
545 	seq_puts(s, "\n");
546 	return 0;
547 }
548 DEBUGFS_ATTR_RW(margining_mode);
549 
550 static int margining_run_write(void *data, u64 val)
551 {
552 	struct tb_port *port = data;
553 	struct usb4_port *usb4 = port->usb4;
554 	struct tb_switch *sw = port->sw;
555 	struct tb_margining *margining;
556 	struct tb *tb = sw->tb;
557 	int ret;
558 
559 	if (val != 1)
560 		return -EINVAL;
561 
562 	pm_runtime_get_sync(&sw->dev);
563 
564 	if (mutex_lock_interruptible(&tb->lock)) {
565 		ret = -ERESTARTSYS;
566 		goto out_rpm_put;
567 	}
568 
569 	/*
570 	 * CL states may interfere with lane margining so inform the user know
571 	 * and bail out.
572 	 */
573 	if (tb_port_is_clx_enabled(port, TB_CL1 | TB_CL2)) {
574 		tb_port_warn(port,
575 			     "CL states are enabled, Disable them with clx=0 and re-connect\n");
576 		ret = -EINVAL;
577 		goto out_unlock;
578 	}
579 
580 	margining = usb4->margining;
581 
582 	if (margining->software) {
583 		tb_port_dbg(port, "running software %s lane margining for lanes %u\n",
584 			    margining->time ? "time" : "voltage", margining->lanes);
585 		ret = usb4_port_sw_margin(port, margining->lanes, margining->time,
586 					  margining->right_high,
587 					  USB4_MARGIN_SW_COUNTER_CLEAR);
588 		if (ret)
589 			goto out_unlock;
590 
591 		ret = usb4_port_sw_margin_errors(port, &margining->results[0]);
592 	} else {
593 		tb_port_dbg(port, "running hardware %s lane margining for lanes %u\n",
594 			    margining->time ? "time" : "voltage", margining->lanes);
595 		/* Clear the results */
596 		margining->results[0] = 0;
597 		margining->results[1] = 0;
598 		ret = usb4_port_hw_margin(port, margining->lanes,
599 					  margining->ber_level, margining->time,
600 					  margining->right_high, margining->results);
601 	}
602 
603 out_unlock:
604 	mutex_unlock(&tb->lock);
605 out_rpm_put:
606 	pm_runtime_mark_last_busy(&sw->dev);
607 	pm_runtime_put_autosuspend(&sw->dev);
608 
609 	return ret;
610 }
611 DEFINE_DEBUGFS_ATTRIBUTE(margining_run_fops, NULL, margining_run_write,
612 			 "%llu\n");
613 
614 static ssize_t margining_results_write(struct file *file,
615 				       const char __user *user_buf,
616 				       size_t count, loff_t *ppos)
617 {
618 	struct seq_file *s = file->private_data;
619 	struct tb_port *port = s->private;
620 	struct usb4_port *usb4 = port->usb4;
621 	struct tb *tb = port->sw->tb;
622 
623 	if (mutex_lock_interruptible(&tb->lock))
624 		return -ERESTARTSYS;
625 
626 	/* Just clear the results */
627 	usb4->margining->results[0] = 0;
628 	usb4->margining->results[1] = 0;
629 
630 	mutex_unlock(&tb->lock);
631 	return count;
632 }
633 
634 static void voltage_margin_show(struct seq_file *s,
635 				const struct tb_margining *margining, u8 val)
636 {
637 	unsigned int tmp, voltage;
638 
639 	tmp = val & USB4_MARGIN_HW_RES_1_MARGIN_MASK;
640 	voltage = tmp * margining->max_voltage_offset / margining->voltage_steps;
641 	seq_printf(s, "%u mV (%u)", voltage, tmp);
642 	if (val & USB4_MARGIN_HW_RES_1_EXCEEDS)
643 		seq_puts(s, " exceeds maximum");
644 	seq_puts(s, "\n");
645 }
646 
647 static void time_margin_show(struct seq_file *s,
648 			     const struct tb_margining *margining, u8 val)
649 {
650 	unsigned int tmp, interval;
651 
652 	tmp = val & USB4_MARGIN_HW_RES_1_MARGIN_MASK;
653 	interval = tmp * margining->max_time_offset / margining->time_steps;
654 	seq_printf(s, "%u mUI (%u)", interval, tmp);
655 	if (val & USB4_MARGIN_HW_RES_1_EXCEEDS)
656 		seq_puts(s, " exceeds maximum");
657 	seq_puts(s, "\n");
658 }
659 
660 static int margining_results_show(struct seq_file *s, void *not_used)
661 {
662 	struct tb_port *port = s->private;
663 	struct usb4_port *usb4 = port->usb4;
664 	struct tb_margining *margining;
665 	struct tb *tb = port->sw->tb;
666 
667 	if (mutex_lock_interruptible(&tb->lock))
668 		return -ERESTARTSYS;
669 
670 	margining = usb4->margining;
671 	/* Dump the raw results first */
672 	seq_printf(s, "0x%08x\n", margining->results[0]);
673 	/* Only the hardware margining has two result dwords */
674 	if (!margining->software) {
675 		unsigned int val;
676 
677 		seq_printf(s, "0x%08x\n", margining->results[1]);
678 
679 		if (margining->time) {
680 			if (!margining->lanes || margining->lanes == 7) {
681 				val = margining->results[1];
682 				seq_puts(s, "# lane 0 right time margin: ");
683 				time_margin_show(s, margining, val);
684 				val = margining->results[1] >>
685 					USB4_MARGIN_HW_RES_1_L0_LL_MARGIN_SHIFT;
686 				seq_puts(s, "# lane 0 left time margin: ");
687 				time_margin_show(s, margining, val);
688 			}
689 			if (margining->lanes == 1 || margining->lanes == 7) {
690 				val = margining->results[1] >>
691 					USB4_MARGIN_HW_RES_1_L1_RH_MARGIN_SHIFT;
692 				seq_puts(s, "# lane 1 right time margin: ");
693 				time_margin_show(s, margining, val);
694 				val = margining->results[1] >>
695 					USB4_MARGIN_HW_RES_1_L1_LL_MARGIN_SHIFT;
696 				seq_puts(s, "# lane 1 left time margin: ");
697 				time_margin_show(s, margining, val);
698 			}
699 		} else {
700 			if (!margining->lanes || margining->lanes == 7) {
701 				val = margining->results[1];
702 				seq_puts(s, "# lane 0 high voltage margin: ");
703 				voltage_margin_show(s, margining, val);
704 				val = margining->results[1] >>
705 					USB4_MARGIN_HW_RES_1_L0_LL_MARGIN_SHIFT;
706 				seq_puts(s, "# lane 0 low voltage margin: ");
707 				voltage_margin_show(s, margining, val);
708 			}
709 			if (margining->lanes == 1 || margining->lanes == 7) {
710 				val = margining->results[1] >>
711 					USB4_MARGIN_HW_RES_1_L1_RH_MARGIN_SHIFT;
712 				seq_puts(s, "# lane 1 high voltage margin: ");
713 				voltage_margin_show(s, margining, val);
714 				val = margining->results[1] >>
715 					USB4_MARGIN_HW_RES_1_L1_LL_MARGIN_SHIFT;
716 				seq_puts(s, "# lane 1 low voltage margin: ");
717 				voltage_margin_show(s, margining, val);
718 			}
719 		}
720 	}
721 
722 	mutex_unlock(&tb->lock);
723 	return 0;
724 }
725 DEBUGFS_ATTR_RW(margining_results);
726 
727 static ssize_t margining_test_write(struct file *file,
728 				    const char __user *user_buf,
729 				    size_t count, loff_t *ppos)
730 {
731 	struct seq_file *s = file->private_data;
732 	struct tb_port *port = s->private;
733 	struct usb4_port *usb4 = port->usb4;
734 	struct tb *tb = port->sw->tb;
735 	int ret = 0;
736 	char *buf;
737 
738 	buf = validate_and_copy_from_user(user_buf, &count);
739 	if (IS_ERR(buf))
740 		return PTR_ERR(buf);
741 
742 	buf[count - 1] = '\0';
743 
744 	if (mutex_lock_interruptible(&tb->lock)) {
745 		ret = -ERESTARTSYS;
746 		goto out_free;
747 	}
748 
749 	if (!strcmp(buf, "time") && supports_time(usb4))
750 		usb4->margining->time = true;
751 	else if (!strcmp(buf, "voltage"))
752 		usb4->margining->time = false;
753 	else
754 		ret = -EINVAL;
755 
756 	mutex_unlock(&tb->lock);
757 
758 out_free:
759 	free_page((unsigned long)buf);
760 	return ret ? ret : count;
761 }
762 
763 static int margining_test_show(struct seq_file *s, void *not_used)
764 {
765 	struct tb_port *port = s->private;
766 	struct usb4_port *usb4 = port->usb4;
767 	struct tb *tb = port->sw->tb;
768 
769 	if (mutex_lock_interruptible(&tb->lock))
770 		return -ERESTARTSYS;
771 
772 	if (supports_time(usb4)) {
773 		if (usb4->margining->time)
774 			seq_puts(s, "voltage [time]\n");
775 		else
776 			seq_puts(s, "[voltage] time\n");
777 	} else {
778 		seq_puts(s, "[voltage]\n");
779 	}
780 
781 	mutex_unlock(&tb->lock);
782 	return 0;
783 }
784 DEBUGFS_ATTR_RW(margining_test);
785 
786 static ssize_t margining_margin_write(struct file *file,
787 				    const char __user *user_buf,
788 				    size_t count, loff_t *ppos)
789 {
790 	struct seq_file *s = file->private_data;
791 	struct tb_port *port = s->private;
792 	struct usb4_port *usb4 = port->usb4;
793 	struct tb *tb = port->sw->tb;
794 	int ret = 0;
795 	char *buf;
796 
797 	buf = validate_and_copy_from_user(user_buf, &count);
798 	if (IS_ERR(buf))
799 		return PTR_ERR(buf);
800 
801 	buf[count - 1] = '\0';
802 
803 	if (mutex_lock_interruptible(&tb->lock)) {
804 		ret = -ERESTARTSYS;
805 		goto out_free;
806 	}
807 
808 	if (usb4->margining->time) {
809 		if (!strcmp(buf, "left"))
810 			usb4->margining->right_high = false;
811 		else if (!strcmp(buf, "right"))
812 			usb4->margining->right_high = true;
813 		else
814 			ret = -EINVAL;
815 	} else {
816 		if (!strcmp(buf, "low"))
817 			usb4->margining->right_high = false;
818 		else if (!strcmp(buf, "high"))
819 			usb4->margining->right_high = true;
820 		else
821 			ret = -EINVAL;
822 	}
823 
824 	mutex_unlock(&tb->lock);
825 
826 out_free:
827 	free_page((unsigned long)buf);
828 	return ret ? ret : count;
829 }
830 
831 static int margining_margin_show(struct seq_file *s, void *not_used)
832 {
833 	struct tb_port *port = s->private;
834 	struct usb4_port *usb4 = port->usb4;
835 	struct tb *tb = port->sw->tb;
836 
837 	if (mutex_lock_interruptible(&tb->lock))
838 		return -ERESTARTSYS;
839 
840 	if (usb4->margining->time) {
841 		if (usb4->margining->right_high)
842 			seq_puts(s, "left [right]\n");
843 		else
844 			seq_puts(s, "[left] right\n");
845 	} else {
846 		if (usb4->margining->right_high)
847 			seq_puts(s, "low [high]\n");
848 		else
849 			seq_puts(s, "[low] high\n");
850 	}
851 
852 	mutex_unlock(&tb->lock);
853 	return 0;
854 }
855 DEBUGFS_ATTR_RW(margining_margin);
856 
857 static void margining_port_init(struct tb_port *port)
858 {
859 	struct tb_margining *margining;
860 	struct dentry *dir, *parent;
861 	struct usb4_port *usb4;
862 	char dir_name[10];
863 	unsigned int val;
864 	int ret;
865 
866 	usb4 = port->usb4;
867 	if (!usb4)
868 		return;
869 
870 	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
871 	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
872 
873 	margining = kzalloc(sizeof(*margining), GFP_KERNEL);
874 	if (!margining)
875 		return;
876 
877 	ret = usb4_port_margining_caps(port, margining->caps);
878 	if (ret) {
879 		kfree(margining);
880 		return;
881 	}
882 
883 	usb4->margining = margining;
884 
885 	/* Set the initial mode */
886 	if (supports_software(usb4))
887 		margining->software = true;
888 
889 	val = (margining->caps[0] & USB4_MARGIN_CAP_0_VOLTAGE_STEPS_MASK) >>
890 		USB4_MARGIN_CAP_0_VOLTAGE_STEPS_SHIFT;
891 	margining->voltage_steps = val;
892 	val = (margining->caps[0] & USB4_MARGIN_CAP_0_MAX_VOLTAGE_OFFSET_MASK) >>
893 		USB4_MARGIN_CAP_0_MAX_VOLTAGE_OFFSET_SHIFT;
894 	margining->max_voltage_offset = 74 + val * 2;
895 
896 	if (supports_time(usb4)) {
897 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_TIME_STEPS_MASK) >>
898 			USB4_MARGIN_CAP_1_TIME_STEPS_SHIFT;
899 		margining->time_steps = val;
900 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_TIME_OFFSET_MASK) >>
901 			USB4_MARGIN_CAP_1_TIME_OFFSET_SHIFT;
902 		/*
903 		 * Store it as mUI (milli Unit Interval) because we want
904 		 * to keep it as integer.
905 		 */
906 		margining->max_time_offset = 200 + 10 * val;
907 	}
908 
909 	dir = debugfs_create_dir("margining", parent);
910 	if (supports_hardware(usb4)) {
911 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_MIN_BER_MASK) >>
912 			USB4_MARGIN_CAP_1_MIN_BER_SHIFT;
913 		margining->min_ber_level = val;
914 		val = (margining->caps[1] & USB4_MARGIN_CAP_1_MAX_BER_MASK) >>
915 			USB4_MARGIN_CAP_1_MAX_BER_SHIFT;
916 		margining->max_ber_level = val;
917 
918 		/* Set the default to minimum */
919 		margining->ber_level = margining->min_ber_level;
920 
921 		debugfs_create_file("ber_level_contour", 0400, dir, port,
922 				    &margining_ber_level_fops);
923 	}
924 	debugfs_create_file("caps", 0400, dir, port, &margining_caps_fops);
925 	debugfs_create_file("lanes", 0600, dir, port, &margining_lanes_fops);
926 	debugfs_create_file("mode", 0600, dir, port, &margining_mode_fops);
927 	debugfs_create_file("run", 0600, dir, port, &margining_run_fops);
928 	debugfs_create_file("results", 0600, dir, port, &margining_results_fops);
929 	debugfs_create_file("test", 0600, dir, port, &margining_test_fops);
930 	if (independent_voltage_margins(usb4) ||
931 	    (supports_time(usb4) && independent_time_margins(usb4)))
932 		debugfs_create_file("margin", 0600, dir, port, &margining_margin_fops);
933 }
934 
935 static void margining_port_remove(struct tb_port *port)
936 {
937 	struct dentry *parent;
938 	char dir_name[10];
939 
940 	if (!port->usb4)
941 		return;
942 
943 	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
944 	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
945 	debugfs_remove_recursive(debugfs_lookup("margining", parent));
946 
947 	kfree(port->usb4->margining);
948 	port->usb4->margining = NULL;
949 }
950 
951 static void margining_switch_init(struct tb_switch *sw)
952 {
953 	struct tb_port *upstream, *downstream;
954 	struct tb_switch *parent_sw;
955 	u64 route = tb_route(sw);
956 
957 	if (!route)
958 		return;
959 
960 	upstream = tb_upstream_port(sw);
961 	parent_sw = tb_switch_parent(sw);
962 	downstream = tb_port_at(route, parent_sw);
963 
964 	margining_port_init(downstream);
965 	margining_port_init(upstream);
966 }
967 
968 static void margining_switch_remove(struct tb_switch *sw)
969 {
970 	struct tb_switch *parent_sw;
971 	struct tb_port *downstream;
972 	u64 route = tb_route(sw);
973 
974 	if (!route)
975 		return;
976 
977 	/*
978 	 * Upstream is removed with the router itself but we need to
979 	 * remove the downstream port margining directory.
980 	 */
981 	parent_sw = tb_switch_parent(sw);
982 	downstream = tb_port_at(route, parent_sw);
983 	margining_port_remove(downstream);
984 }
985 
986 static void margining_xdomain_init(struct tb_xdomain *xd)
987 {
988 	struct tb_switch *parent_sw;
989 	struct tb_port *downstream;
990 
991 	parent_sw = tb_xdomain_parent(xd);
992 	downstream = tb_port_at(xd->route, parent_sw);
993 
994 	margining_port_init(downstream);
995 }
996 
997 static void margining_xdomain_remove(struct tb_xdomain *xd)
998 {
999 	struct tb_switch *parent_sw;
1000 	struct tb_port *downstream;
1001 
1002 	parent_sw = tb_xdomain_parent(xd);
1003 	downstream = tb_port_at(xd->route, parent_sw);
1004 	margining_port_remove(downstream);
1005 }
1006 #else
1007 static inline void margining_switch_init(struct tb_switch *sw) { }
1008 static inline void margining_switch_remove(struct tb_switch *sw) { }
1009 static inline void margining_xdomain_init(struct tb_xdomain *xd) { }
1010 static inline void margining_xdomain_remove(struct tb_xdomain *xd) { }
1011 #endif
1012 
1013 static int port_clear_all_counters(struct tb_port *port)
1014 {
1015 	u32 *buf;
1016 	int ret;
1017 
1018 	buf = kcalloc(COUNTER_SET_LEN * port->config.max_counters, sizeof(u32),
1019 		      GFP_KERNEL);
1020 	if (!buf)
1021 		return -ENOMEM;
1022 
1023 	ret = tb_port_write(port, buf, TB_CFG_COUNTERS, 0,
1024 			    COUNTER_SET_LEN * port->config.max_counters);
1025 	kfree(buf);
1026 
1027 	return ret;
1028 }
1029 
1030 static ssize_t counters_write(struct file *file, const char __user *user_buf,
1031 			      size_t count, loff_t *ppos)
1032 {
1033 	struct seq_file *s = file->private_data;
1034 	struct tb_port *port = s->private;
1035 	struct tb_switch *sw = port->sw;
1036 	struct tb *tb = port->sw->tb;
1037 	char *buf;
1038 	int ret;
1039 
1040 	buf = validate_and_copy_from_user(user_buf, &count);
1041 	if (IS_ERR(buf))
1042 		return PTR_ERR(buf);
1043 
1044 	pm_runtime_get_sync(&sw->dev);
1045 
1046 	if (mutex_lock_interruptible(&tb->lock)) {
1047 		ret = -ERESTARTSYS;
1048 		goto out;
1049 	}
1050 
1051 	/* If written delimiter only, clear all counters in one shot */
1052 	if (buf[0] == '\n') {
1053 		ret = port_clear_all_counters(port);
1054 	} else  {
1055 		char *line = buf;
1056 		u32 val, offset;
1057 
1058 		ret = -EINVAL;
1059 		while (parse_line(&line, &offset, &val, 1, 4)) {
1060 			ret = tb_port_write(port, &val, TB_CFG_COUNTERS,
1061 					    offset, 1);
1062 			if (ret)
1063 				break;
1064 		}
1065 	}
1066 
1067 	mutex_unlock(&tb->lock);
1068 
1069 out:
1070 	pm_runtime_mark_last_busy(&sw->dev);
1071 	pm_runtime_put_autosuspend(&sw->dev);
1072 	free_page((unsigned long)buf);
1073 
1074 	return ret < 0 ? ret : count;
1075 }
1076 
1077 static void cap_show_by_dw(struct seq_file *s, struct tb_switch *sw,
1078 			   struct tb_port *port, unsigned int cap,
1079 			   unsigned int offset, u8 cap_id, u8 vsec_id,
1080 			   int dwords)
1081 {
1082 	int i, ret;
1083 	u32 data;
1084 
1085 	for (i = 0; i < dwords; i++) {
1086 		if (port)
1087 			ret = tb_port_read(port, &data, TB_CFG_PORT, cap + offset + i, 1);
1088 		else
1089 			ret = tb_sw_read(sw, &data, TB_CFG_SWITCH, cap + offset + i, 1);
1090 		if (ret) {
1091 			seq_printf(s, "0x%04x <not accessible>\n", cap + offset + i);
1092 			continue;
1093 		}
1094 
1095 		seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n", cap + offset + i,
1096 			   offset + i, cap_id, vsec_id, data);
1097 	}
1098 }
1099 
1100 static void cap_show(struct seq_file *s, struct tb_switch *sw,
1101 		     struct tb_port *port, unsigned int cap, u8 cap_id,
1102 		     u8 vsec_id, int length)
1103 {
1104 	int ret, offset = 0;
1105 
1106 	while (length > 0) {
1107 		int i, dwords = min(length, TB_MAX_CONFIG_RW_LENGTH);
1108 		u32 data[TB_MAX_CONFIG_RW_LENGTH];
1109 
1110 		if (port)
1111 			ret = tb_port_read(port, data, TB_CFG_PORT, cap + offset,
1112 					   dwords);
1113 		else
1114 			ret = tb_sw_read(sw, data, TB_CFG_SWITCH, cap + offset, dwords);
1115 		if (ret) {
1116 			cap_show_by_dw(s, sw, port, cap, offset, cap_id, vsec_id, length);
1117 			return;
1118 		}
1119 
1120 		for (i = 0; i < dwords; i++) {
1121 			seq_printf(s, "0x%04x %4d 0x%02x 0x%02x 0x%08x\n",
1122 				   cap + offset + i, offset + i,
1123 				   cap_id, vsec_id, data[i]);
1124 		}
1125 
1126 		length -= dwords;
1127 		offset += dwords;
1128 	}
1129 }
1130 
1131 static void port_cap_show(struct tb_port *port, struct seq_file *s,
1132 			  unsigned int cap)
1133 {
1134 	struct tb_cap_any header;
1135 	u8 vsec_id = 0;
1136 	size_t length;
1137 	int ret;
1138 
1139 	ret = tb_port_read(port, &header, TB_CFG_PORT, cap, 1);
1140 	if (ret) {
1141 		seq_printf(s, "0x%04x <capability read failed>\n", cap);
1142 		return;
1143 	}
1144 
1145 	switch (header.basic.cap) {
1146 	case TB_PORT_CAP_PHY:
1147 		length = PORT_CAP_LANE_LEN;
1148 		break;
1149 
1150 	case TB_PORT_CAP_TIME1:
1151 		length = PORT_CAP_TMU_LEN;
1152 		break;
1153 
1154 	case TB_PORT_CAP_POWER:
1155 		length = PORT_CAP_POWER_LEN;
1156 		break;
1157 
1158 	case TB_PORT_CAP_ADAP:
1159 		if (tb_port_is_pcie_down(port) || tb_port_is_pcie_up(port)) {
1160 			length = PORT_CAP_PCIE_LEN;
1161 		} else if (tb_port_is_dpin(port) || tb_port_is_dpout(port)) {
1162 			if (usb4_dp_port_bw_mode_supported(port))
1163 				length = PORT_CAP_DP_LEN + 1;
1164 			else
1165 				length = PORT_CAP_DP_LEN;
1166 		} else if (tb_port_is_usb3_down(port) ||
1167 			   tb_port_is_usb3_up(port)) {
1168 			length = PORT_CAP_USB3_LEN;
1169 		} else {
1170 			seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
1171 				   cap, header.basic.cap);
1172 			return;
1173 		}
1174 		break;
1175 
1176 	case TB_PORT_CAP_VSE:
1177 		if (!header.extended_short.length) {
1178 			ret = tb_port_read(port, (u32 *)&header + 1, TB_CFG_PORT,
1179 					   cap + 1, 1);
1180 			if (ret) {
1181 				seq_printf(s, "0x%04x <capability read failed>\n",
1182 					   cap + 1);
1183 				return;
1184 			}
1185 			length = header.extended_long.length;
1186 			vsec_id = header.extended_short.vsec_id;
1187 		} else {
1188 			length = header.extended_short.length;
1189 			vsec_id = header.extended_short.vsec_id;
1190 		}
1191 		break;
1192 
1193 	case TB_PORT_CAP_USB4:
1194 		length = PORT_CAP_USB4_LEN;
1195 		break;
1196 
1197 	default:
1198 		seq_printf(s, "0x%04x <unsupported capability 0x%02x>\n",
1199 			   cap, header.basic.cap);
1200 		return;
1201 	}
1202 
1203 	cap_show(s, NULL, port, cap, header.basic.cap, vsec_id, length);
1204 }
1205 
1206 static void port_caps_show(struct tb_port *port, struct seq_file *s)
1207 {
1208 	int cap;
1209 
1210 	cap = tb_port_next_cap(port, 0);
1211 	while (cap > 0) {
1212 		port_cap_show(port, s, cap);
1213 		cap = tb_port_next_cap(port, cap);
1214 	}
1215 }
1216 
1217 static int port_basic_regs_show(struct tb_port *port, struct seq_file *s)
1218 {
1219 	u32 data[PORT_CAP_BASIC_LEN];
1220 	int ret, i;
1221 
1222 	ret = tb_port_read(port, data, TB_CFG_PORT, 0, ARRAY_SIZE(data));
1223 	if (ret)
1224 		return ret;
1225 
1226 	for (i = 0; i < ARRAY_SIZE(data); i++)
1227 		seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
1228 
1229 	return 0;
1230 }
1231 
1232 static int port_regs_show(struct seq_file *s, void *not_used)
1233 {
1234 	struct tb_port *port = s->private;
1235 	struct tb_switch *sw = port->sw;
1236 	struct tb *tb = sw->tb;
1237 	int ret;
1238 
1239 	pm_runtime_get_sync(&sw->dev);
1240 
1241 	if (mutex_lock_interruptible(&tb->lock)) {
1242 		ret = -ERESTARTSYS;
1243 		goto out_rpm_put;
1244 	}
1245 
1246 	seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
1247 
1248 	ret = port_basic_regs_show(port, s);
1249 	if (ret)
1250 		goto out_unlock;
1251 
1252 	port_caps_show(port, s);
1253 
1254 out_unlock:
1255 	mutex_unlock(&tb->lock);
1256 out_rpm_put:
1257 	pm_runtime_mark_last_busy(&sw->dev);
1258 	pm_runtime_put_autosuspend(&sw->dev);
1259 
1260 	return ret;
1261 }
1262 DEBUGFS_ATTR_RW(port_regs);
1263 
1264 static void switch_cap_show(struct tb_switch *sw, struct seq_file *s,
1265 			    unsigned int cap)
1266 {
1267 	struct tb_cap_any header;
1268 	int ret, length;
1269 	u8 vsec_id = 0;
1270 
1271 	ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, cap, 1);
1272 	if (ret) {
1273 		seq_printf(s, "0x%04x <capability read failed>\n", cap);
1274 		return;
1275 	}
1276 
1277 	if (header.basic.cap == TB_SWITCH_CAP_VSE) {
1278 		if (!header.extended_short.length) {
1279 			ret = tb_sw_read(sw, (u32 *)&header + 1, TB_CFG_SWITCH,
1280 					 cap + 1, 1);
1281 			if (ret) {
1282 				seq_printf(s, "0x%04x <capability read failed>\n",
1283 					   cap + 1);
1284 				return;
1285 			}
1286 			length = header.extended_long.length;
1287 		} else {
1288 			length = header.extended_short.length;
1289 		}
1290 		vsec_id = header.extended_short.vsec_id;
1291 	} else {
1292 		if (header.basic.cap == TB_SWITCH_CAP_TMU) {
1293 			length = SWITCH_CAP_TMU_LEN;
1294 		} else  {
1295 			seq_printf(s, "0x%04x <unknown capability 0x%02x>\n",
1296 				   cap, header.basic.cap);
1297 			return;
1298 		}
1299 	}
1300 
1301 	cap_show(s, sw, NULL, cap, header.basic.cap, vsec_id, length);
1302 }
1303 
1304 static void switch_caps_show(struct tb_switch *sw, struct seq_file *s)
1305 {
1306 	int cap;
1307 
1308 	cap = tb_switch_next_cap(sw, 0);
1309 	while (cap > 0) {
1310 		switch_cap_show(sw, s, cap);
1311 		cap = tb_switch_next_cap(sw, cap);
1312 	}
1313 }
1314 
1315 static int switch_basic_regs_show(struct tb_switch *sw, struct seq_file *s)
1316 {
1317 	u32 data[SWITCH_CAP_BASIC_LEN];
1318 	size_t dwords;
1319 	int ret, i;
1320 
1321 	/* Only USB4 has the additional registers */
1322 	if (tb_switch_is_usb4(sw))
1323 		dwords = ARRAY_SIZE(data);
1324 	else
1325 		dwords = 7;
1326 
1327 	ret = tb_sw_read(sw, data, TB_CFG_SWITCH, 0, dwords);
1328 	if (ret)
1329 		return ret;
1330 
1331 	for (i = 0; i < dwords; i++)
1332 		seq_printf(s, "0x%04x %4d 0x00 0x00 0x%08x\n", i, i, data[i]);
1333 
1334 	return 0;
1335 }
1336 
1337 static int switch_regs_show(struct seq_file *s, void *not_used)
1338 {
1339 	struct tb_switch *sw = s->private;
1340 	struct tb *tb = sw->tb;
1341 	int ret;
1342 
1343 	pm_runtime_get_sync(&sw->dev);
1344 
1345 	if (mutex_lock_interruptible(&tb->lock)) {
1346 		ret = -ERESTARTSYS;
1347 		goto out_rpm_put;
1348 	}
1349 
1350 	seq_puts(s, "# offset relative_offset cap_id vs_cap_id value\n");
1351 
1352 	ret = switch_basic_regs_show(sw, s);
1353 	if (ret)
1354 		goto out_unlock;
1355 
1356 	switch_caps_show(sw, s);
1357 
1358 out_unlock:
1359 	mutex_unlock(&tb->lock);
1360 out_rpm_put:
1361 	pm_runtime_mark_last_busy(&sw->dev);
1362 	pm_runtime_put_autosuspend(&sw->dev);
1363 
1364 	return ret;
1365 }
1366 DEBUGFS_ATTR_RW(switch_regs);
1367 
1368 static int path_show_one(struct tb_port *port, struct seq_file *s, int hopid)
1369 {
1370 	u32 data[PATH_LEN];
1371 	int ret, i;
1372 
1373 	ret = tb_port_read(port, data, TB_CFG_HOPS, hopid * PATH_LEN,
1374 			   ARRAY_SIZE(data));
1375 	if (ret) {
1376 		seq_printf(s, "0x%04x <not accessible>\n", hopid * PATH_LEN);
1377 		return ret;
1378 	}
1379 
1380 	for (i = 0; i < ARRAY_SIZE(data); i++) {
1381 		seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
1382 			   hopid * PATH_LEN + i, i, hopid, data[i]);
1383 	}
1384 
1385 	return 0;
1386 }
1387 
1388 static int path_show(struct seq_file *s, void *not_used)
1389 {
1390 	struct tb_port *port = s->private;
1391 	struct tb_switch *sw = port->sw;
1392 	struct tb *tb = sw->tb;
1393 	int start, i, ret = 0;
1394 
1395 	pm_runtime_get_sync(&sw->dev);
1396 
1397 	if (mutex_lock_interruptible(&tb->lock)) {
1398 		ret = -ERESTARTSYS;
1399 		goto out_rpm_put;
1400 	}
1401 
1402 	seq_puts(s, "# offset relative_offset in_hop_id value\n");
1403 
1404 	/* NHI and lane adapters have entry for path 0 */
1405 	if (tb_port_is_null(port) || tb_port_is_nhi(port)) {
1406 		ret = path_show_one(port, s, 0);
1407 		if (ret)
1408 			goto out_unlock;
1409 	}
1410 
1411 	start = tb_port_is_nhi(port) ? 1 : TB_PATH_MIN_HOPID;
1412 
1413 	for (i = start; i <= port->config.max_in_hop_id; i++) {
1414 		ret = path_show_one(port, s, i);
1415 		if (ret)
1416 			break;
1417 	}
1418 
1419 out_unlock:
1420 	mutex_unlock(&tb->lock);
1421 out_rpm_put:
1422 	pm_runtime_mark_last_busy(&sw->dev);
1423 	pm_runtime_put_autosuspend(&sw->dev);
1424 
1425 	return ret;
1426 }
1427 DEBUGFS_ATTR_RO(path);
1428 
1429 static int counter_set_regs_show(struct tb_port *port, struct seq_file *s,
1430 				 int counter)
1431 {
1432 	u32 data[COUNTER_SET_LEN];
1433 	int ret, i;
1434 
1435 	ret = tb_port_read(port, data, TB_CFG_COUNTERS,
1436 			   counter * COUNTER_SET_LEN, ARRAY_SIZE(data));
1437 	if (ret) {
1438 		seq_printf(s, "0x%04x <not accessible>\n",
1439 			   counter * COUNTER_SET_LEN);
1440 		return ret;
1441 	}
1442 
1443 	for (i = 0; i < ARRAY_SIZE(data); i++) {
1444 		seq_printf(s, "0x%04x %4d 0x%02x 0x%08x\n",
1445 			   counter * COUNTER_SET_LEN + i, i, counter, data[i]);
1446 	}
1447 
1448 	return 0;
1449 }
1450 
1451 static int counters_show(struct seq_file *s, void *not_used)
1452 {
1453 	struct tb_port *port = s->private;
1454 	struct tb_switch *sw = port->sw;
1455 	struct tb *tb = sw->tb;
1456 	int i, ret = 0;
1457 
1458 	pm_runtime_get_sync(&sw->dev);
1459 
1460 	if (mutex_lock_interruptible(&tb->lock)) {
1461 		ret = -ERESTARTSYS;
1462 		goto out;
1463 	}
1464 
1465 	seq_puts(s, "# offset relative_offset counter_id value\n");
1466 
1467 	for (i = 0; i < port->config.max_counters; i++) {
1468 		ret = counter_set_regs_show(port, s, i);
1469 		if (ret)
1470 			break;
1471 	}
1472 
1473 	mutex_unlock(&tb->lock);
1474 
1475 out:
1476 	pm_runtime_mark_last_busy(&sw->dev);
1477 	pm_runtime_put_autosuspend(&sw->dev);
1478 
1479 	return ret;
1480 }
1481 DEBUGFS_ATTR_RW(counters);
1482 
1483 /**
1484  * tb_switch_debugfs_init() - Add debugfs entries for router
1485  * @sw: Pointer to the router
1486  *
1487  * Adds debugfs directories and files for given router.
1488  */
1489 void tb_switch_debugfs_init(struct tb_switch *sw)
1490 {
1491 	struct dentry *debugfs_dir;
1492 	struct tb_port *port;
1493 
1494 	debugfs_dir = debugfs_create_dir(dev_name(&sw->dev), tb_debugfs_root);
1495 	sw->debugfs_dir = debugfs_dir;
1496 	debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir, sw,
1497 			    &switch_regs_fops);
1498 
1499 	tb_switch_for_each_port(sw, port) {
1500 		struct dentry *debugfs_dir;
1501 		char dir_name[10];
1502 
1503 		if (port->disabled)
1504 			continue;
1505 		if (port->config.type == TB_TYPE_INACTIVE)
1506 			continue;
1507 
1508 		snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
1509 		debugfs_dir = debugfs_create_dir(dir_name, sw->debugfs_dir);
1510 		debugfs_create_file("regs", DEBUGFS_MODE, debugfs_dir,
1511 				    port, &port_regs_fops);
1512 		debugfs_create_file("path", 0400, debugfs_dir, port,
1513 				    &path_fops);
1514 		if (port->config.counters_support)
1515 			debugfs_create_file("counters", 0600, debugfs_dir, port,
1516 					    &counters_fops);
1517 	}
1518 
1519 	margining_switch_init(sw);
1520 }
1521 
1522 /**
1523  * tb_switch_debugfs_remove() - Remove all router debugfs entries
1524  * @sw: Pointer to the router
1525  *
1526  * Removes all previously added debugfs entries under this router.
1527  */
1528 void tb_switch_debugfs_remove(struct tb_switch *sw)
1529 {
1530 	margining_switch_remove(sw);
1531 	debugfs_remove_recursive(sw->debugfs_dir);
1532 }
1533 
1534 void tb_xdomain_debugfs_init(struct tb_xdomain *xd)
1535 {
1536 	margining_xdomain_init(xd);
1537 }
1538 
1539 void tb_xdomain_debugfs_remove(struct tb_xdomain *xd)
1540 {
1541 	margining_xdomain_remove(xd);
1542 }
1543 
1544 /**
1545  * tb_service_debugfs_init() - Add debugfs directory for service
1546  * @svc: Thunderbolt service pointer
1547  *
1548  * Adds debugfs directory for service.
1549  */
1550 void tb_service_debugfs_init(struct tb_service *svc)
1551 {
1552 	svc->debugfs_dir = debugfs_create_dir(dev_name(&svc->dev),
1553 					      tb_debugfs_root);
1554 }
1555 
1556 /**
1557  * tb_service_debugfs_remove() - Remove service debugfs directory
1558  * @svc: Thunderbolt service pointer
1559  *
1560  * Removes the previously created debugfs directory for @svc.
1561  */
1562 void tb_service_debugfs_remove(struct tb_service *svc)
1563 {
1564 	debugfs_remove_recursive(svc->debugfs_dir);
1565 	svc->debugfs_dir = NULL;
1566 }
1567 
1568 void tb_debugfs_init(void)
1569 {
1570 	tb_debugfs_root = debugfs_create_dir("thunderbolt", NULL);
1571 }
1572 
1573 void tb_debugfs_exit(void)
1574 {
1575 	debugfs_remove_recursive(tb_debugfs_root);
1576 }
1577