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)					\
37static int __space ## _open(struct inode *inode, struct file *file)	\
38{									\
39	return single_open(file, __space ## _show, inode->i_private);	\
40}									\
41									\
42static 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
57static struct dentry *tb_debugfs_root;
58
59static 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
85static 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)
127static 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
162out:
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
170static 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
179static 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 */
212struct 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
228static bool supports_software(const struct usb4_port *usb4)
229{
230	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_SW;
231}
232
233static bool supports_hardware(const struct usb4_port *usb4)
234{
235	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_MODES_HW;
236}
237
238static bool both_lanes(const struct usb4_port *usb4)
239{
240	return usb4->margining->caps[0] & USB4_MARGIN_CAP_0_2_LANES;
241}
242
243static 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
249static 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 */
255static 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
261static ssize_t
262margining_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
301out_free:
302	free_page((unsigned long)buf);
303out_unlock:
304	mutex_unlock(&tb->lock);
305
306	return ret < 0 ? ret : count;
307}
308
309static 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
317static 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}
327DEBUGFS_ATTR_RW(margining_ber_level);
328
329static 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}
404DEBUGFS_ATTR_RO(margining_caps);
405
406static ssize_t
407margining_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
444out_free:
445	free_page((unsigned long)buf);
446	return ret < 0 ? ret : count;
447}
448
449static 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}
477DEBUGFS_ATTR_RW(margining_lanes);
478
479static 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
517out_free:
518	free_page((unsigned long)buf);
519	return ret ? ret : count;
520}
521
522static 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}
551DEBUGFS_ATTR_RW(margining_mode);
552
553static 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
616out_clx:
617	if (down_sw)
618		tb_switch_clx_enable(down_sw, clx);
619out_unlock:
620	mutex_unlock(&tb->lock);
621out_rpm_put:
622	pm_runtime_mark_last_busy(&sw->dev);
623	pm_runtime_put_autosuspend(&sw->dev);
624
625	return ret;
626}
627DEFINE_DEBUGFS_ATTRIBUTE(margining_run_fops, NULL, margining_run_write,
628			 "%llu\n");
629
630static 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
650static 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
663static 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
676static 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}
741DEBUGFS_ATTR_RW(margining_results);
742
743static 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
774out_free:
775	free_page((unsigned long)buf);
776	return ret ? ret : count;
777}
778
779static 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}
800DEBUGFS_ATTR_RW(margining_test);
801
802static 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
842out_free:
843	free_page((unsigned long)buf);
844	return ret ? ret : count;
845}
846
847static 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}
871DEBUGFS_ATTR_RW(margining_margin);
872
873static 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
951static 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
968static 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
985static 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
1002static 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
1013static 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
1023static inline void margining_switch_init(struct tb_switch *sw) { }
1024static inline void margining_switch_remove(struct tb_switch *sw) { }
1025static inline void margining_xdomain_init(struct tb_xdomain *xd) { }
1026static inline void margining_xdomain_remove(struct tb_xdomain *xd) { }
1027#endif
1028
1029static 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
1046static 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
1085out:
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
1093static 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
1116static 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
1147static 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
1230static 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
1241static 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
1256static 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
1278out_unlock:
1279	mutex_unlock(&tb->lock);
1280out_rpm_put:
1281	pm_runtime_mark_last_busy(&sw->dev);
1282	pm_runtime_put_autosuspend(&sw->dev);
1283
1284	return ret;
1285}
1286DEBUGFS_ATTR_RW(port_regs);
1287
1288static 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
1328static 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
1339static 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
1361static 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
1382out_unlock:
1383	mutex_unlock(&tb->lock);
1384out_rpm_put:
1385	pm_runtime_mark_last_busy(&sw->dev);
1386	pm_runtime_put_autosuspend(&sw->dev);
1387
1388	return ret;
1389}
1390DEBUGFS_ATTR_RW(switch_regs);
1391
1392static 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
1412static 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
1443out_unlock:
1444	mutex_unlock(&tb->lock);
1445out_rpm_put:
1446	pm_runtime_mark_last_busy(&sw->dev);
1447	pm_runtime_put_autosuspend(&sw->dev);
1448
1449	return ret;
1450}
1451DEBUGFS_ATTR_RO(path);
1452
1453static 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
1475static 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
1499out:
1500	pm_runtime_mark_last_busy(&sw->dev);
1501	pm_runtime_put_autosuspend(&sw->dev);
1502
1503	return ret;
1504}
1505DEBUGFS_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 */
1513void 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 */
1552void tb_switch_debugfs_remove(struct tb_switch *sw)
1553{
1554	margining_switch_remove(sw);
1555	debugfs_remove_recursive(sw->debugfs_dir);
1556}
1557
1558void tb_xdomain_debugfs_init(struct tb_xdomain *xd)
1559{
1560	margining_xdomain_init(xd);
1561}
1562
1563void 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 */
1574void 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 */
1586void tb_service_debugfs_remove(struct tb_service *svc)
1587{
1588	debugfs_remove_recursive(svc->debugfs_dir);
1589	svc->debugfs_dir = NULL;
1590}
1591
1592void tb_debugfs_init(void)
1593{
1594	tb_debugfs_root = debugfs_create_dir("thunderbolt", NULL);
1595}
1596
1597void tb_debugfs_exit(void)
1598{
1599	debugfs_remove_recursive(tb_debugfs_root);
1600}
1601