1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2020 Intel Corporation
3
4#include <linux/debugfs.h>
5
6#include "ufs-debugfs.h"
7#include <ufs/ufshcd.h>
8#include "ufshcd-priv.h"
9
10static struct dentry *ufs_debugfs_root;
11
12struct ufs_debugfs_attr {
13	const char			*name;
14	mode_t				mode;
15	const struct file_operations	*fops;
16};
17
18/* @file corresponds to a debugfs attribute in directory hba->debugfs_root. */
19static inline struct ufs_hba *hba_from_file(const struct file *file)
20{
21	return d_inode(file->f_path.dentry->d_parent)->i_private;
22}
23
24void __init ufs_debugfs_init(void)
25{
26	ufs_debugfs_root = debugfs_create_dir("ufshcd", NULL);
27}
28
29void ufs_debugfs_exit(void)
30{
31	debugfs_remove_recursive(ufs_debugfs_root);
32}
33
34static int ufs_debugfs_stats_show(struct seq_file *s, void *data)
35{
36	struct ufs_hba *hba = hba_from_file(s->file);
37	struct ufs_event_hist *e = hba->ufs_stats.event;
38
39#define PRT(fmt, typ) \
40	seq_printf(s, fmt, e[UFS_EVT_ ## typ].cnt)
41
42	PRT("PHY Adapter Layer errors (except LINERESET): %llu\n", PA_ERR);
43	PRT("Data Link Layer errors: %llu\n", DL_ERR);
44	PRT("Network Layer errors: %llu\n", NL_ERR);
45	PRT("Transport Layer errors: %llu\n", TL_ERR);
46	PRT("Generic DME errors: %llu\n", DME_ERR);
47	PRT("Auto-hibernate errors: %llu\n", AUTO_HIBERN8_ERR);
48	PRT("IS Fatal errors (CEFES, SBFES, HCFES, DFES): %llu\n", FATAL_ERR);
49	PRT("DME Link Startup errors: %llu\n", LINK_STARTUP_FAIL);
50	PRT("PM Resume errors: %llu\n", RESUME_ERR);
51	PRT("PM Suspend errors : %llu\n", SUSPEND_ERR);
52	PRT("Logical Unit Resets: %llu\n", DEV_RESET);
53	PRT("Host Resets: %llu\n", HOST_RESET);
54	PRT("SCSI command aborts: %llu\n", ABORT);
55#undef PRT
56	return 0;
57}
58DEFINE_SHOW_ATTRIBUTE(ufs_debugfs_stats);
59
60static int ee_usr_mask_get(void *data, u64 *val)
61{
62	struct ufs_hba *hba = data;
63
64	*val = hba->ee_usr_mask;
65	return 0;
66}
67
68static int ufs_debugfs_get_user_access(struct ufs_hba *hba)
69__acquires(&hba->host_sem)
70{
71	down(&hba->host_sem);
72	if (!ufshcd_is_user_access_allowed(hba)) {
73		up(&hba->host_sem);
74		return -EBUSY;
75	}
76	ufshcd_rpm_get_sync(hba);
77	return 0;
78}
79
80static void ufs_debugfs_put_user_access(struct ufs_hba *hba)
81__releases(&hba->host_sem)
82{
83	ufshcd_rpm_put_sync(hba);
84	up(&hba->host_sem);
85}
86
87static int ee_usr_mask_set(void *data, u64 val)
88{
89	struct ufs_hba *hba = data;
90	int err;
91
92	if (val & ~(u64)MASK_EE_STATUS)
93		return -EINVAL;
94	err = ufs_debugfs_get_user_access(hba);
95	if (err)
96		return err;
97	err = ufshcd_update_ee_usr_mask(hba, val, MASK_EE_STATUS);
98	ufs_debugfs_put_user_access(hba);
99	return err;
100}
101
102DEFINE_DEBUGFS_ATTRIBUTE(ee_usr_mask_fops, ee_usr_mask_get, ee_usr_mask_set, "%#llx\n");
103
104void ufs_debugfs_exception_event(struct ufs_hba *hba, u16 status)
105{
106	bool chgd = false;
107	u16 ee_ctrl_mask;
108	int err = 0;
109
110	if (!hba->debugfs_ee_rate_limit_ms || !status)
111		return;
112
113	mutex_lock(&hba->ee_ctrl_mutex);
114	ee_ctrl_mask = hba->ee_drv_mask | (hba->ee_usr_mask & ~status);
115	chgd = ee_ctrl_mask != hba->ee_ctrl_mask;
116	if (chgd) {
117		err = __ufshcd_write_ee_control(hba, ee_ctrl_mask);
118		if (err)
119			dev_err(hba->dev, "%s: failed to write ee control %d\n",
120				__func__, err);
121	}
122	mutex_unlock(&hba->ee_ctrl_mutex);
123
124	if (chgd && !err) {
125		unsigned long delay = msecs_to_jiffies(hba->debugfs_ee_rate_limit_ms);
126
127		queue_delayed_work(system_freezable_wq, &hba->debugfs_ee_work, delay);
128	}
129}
130
131static void ufs_debugfs_restart_ee(struct work_struct *work)
132{
133	struct ufs_hba *hba = container_of(work, struct ufs_hba, debugfs_ee_work.work);
134
135	if (!hba->ee_usr_mask || pm_runtime_suspended(hba->dev) ||
136	    ufs_debugfs_get_user_access(hba))
137		return;
138	ufshcd_write_ee_control(hba);
139	ufs_debugfs_put_user_access(hba);
140}
141
142static int ufs_saved_err_show(struct seq_file *s, void *data)
143{
144	struct ufs_debugfs_attr *attr = s->private;
145	struct ufs_hba *hba = hba_from_file(s->file);
146	const int *p;
147
148	if (strcmp(attr->name, "saved_err") == 0) {
149		p = &hba->saved_err;
150	} else if (strcmp(attr->name, "saved_uic_err") == 0) {
151		p = &hba->saved_uic_err;
152	} else {
153		return -ENOENT;
154	}
155
156	seq_printf(s, "%d\n", *p);
157	return 0;
158}
159
160static ssize_t ufs_saved_err_write(struct file *file, const char __user *buf,
161				   size_t count, loff_t *ppos)
162{
163	struct ufs_debugfs_attr *attr = file->f_inode->i_private;
164	struct ufs_hba *hba = hba_from_file(file);
165	char val_str[16] = { };
166	int val, ret;
167
168	if (count > sizeof(val_str))
169		return -EINVAL;
170	if (copy_from_user(val_str, buf, count))
171		return -EFAULT;
172	ret = kstrtoint(val_str, 0, &val);
173	if (ret < 0)
174		return ret;
175
176	spin_lock_irq(hba->host->host_lock);
177	if (strcmp(attr->name, "saved_err") == 0) {
178		hba->saved_err = val;
179	} else if (strcmp(attr->name, "saved_uic_err") == 0) {
180		hba->saved_uic_err = val;
181	} else {
182		ret = -ENOENT;
183	}
184	if (ret == 0)
185		ufshcd_schedule_eh_work(hba);
186	spin_unlock_irq(hba->host->host_lock);
187
188	return ret < 0 ? ret : count;
189}
190
191static int ufs_saved_err_open(struct inode *inode, struct file *file)
192{
193	return single_open(file, ufs_saved_err_show, inode->i_private);
194}
195
196static const struct file_operations ufs_saved_err_fops = {
197	.owner		= THIS_MODULE,
198	.open		= ufs_saved_err_open,
199	.read		= seq_read,
200	.write		= ufs_saved_err_write,
201	.llseek		= seq_lseek,
202	.release	= single_release,
203};
204
205static const struct ufs_debugfs_attr ufs_attrs[] = {
206	{ "stats", 0400, &ufs_debugfs_stats_fops },
207	{ "saved_err", 0600, &ufs_saved_err_fops },
208	{ "saved_uic_err", 0600, &ufs_saved_err_fops },
209	{ }
210};
211
212void ufs_debugfs_hba_init(struct ufs_hba *hba)
213{
214	const struct ufs_debugfs_attr *attr;
215	struct dentry *root;
216
217	/* Set default exception event rate limit period to 20ms */
218	hba->debugfs_ee_rate_limit_ms = 20;
219	INIT_DELAYED_WORK(&hba->debugfs_ee_work, ufs_debugfs_restart_ee);
220
221	root = debugfs_create_dir(dev_name(hba->dev), ufs_debugfs_root);
222	if (IS_ERR_OR_NULL(root))
223		return;
224	hba->debugfs_root = root;
225	d_inode(root)->i_private = hba;
226	for (attr = ufs_attrs; attr->name; attr++)
227		debugfs_create_file(attr->name, attr->mode, root, (void *)attr,
228				    attr->fops);
229	debugfs_create_file("exception_event_mask", 0600, hba->debugfs_root,
230			    hba, &ee_usr_mask_fops);
231	debugfs_create_u32("exception_event_rate_limit_ms", 0600, hba->debugfs_root,
232			   &hba->debugfs_ee_rate_limit_ms);
233}
234
235void ufs_debugfs_hba_exit(struct ufs_hba *hba)
236{
237	debugfs_remove_recursive(hba->debugfs_root);
238	cancel_delayed_work_sync(&hba->debugfs_ee_work);
239}
240