xref: /linux/kernel/irq/debugfs.c (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright 2017 Thomas Gleixner <tglx@linutronix.de>
3 
4 #include <linux/irqdomain.h>
5 #include <linux/irq.h>
6 #include <linux/uaccess.h>
7 
8 #include "internals.h"
9 
10 static struct dentry *irq_dir;
11 
12 struct irq_bit_descr {
13 	unsigned int	mask;
14 	char		*name;
15 };
16 #define BIT_MASK_DESCR(m)	{ .mask = m, .name = #m }
17 
18 static void irq_debug_show_bits(struct seq_file *m, int ind, unsigned int state,
19 				const struct irq_bit_descr *sd, int size)
20 {
21 	int i;
22 
23 	for (i = 0; i < size; i++, sd++) {
24 		if (state & sd->mask)
25 			seq_printf(m, "%*s%s\n", ind + 12, "", sd->name);
26 	}
27 }
28 
29 #ifdef CONFIG_SMP
30 static void irq_debug_show_masks(struct seq_file *m, struct irq_desc *desc)
31 {
32 	struct irq_data *data = irq_desc_get_irq_data(desc);
33 	const struct cpumask *msk;
34 
35 	msk = irq_data_get_affinity_mask(data);
36 	seq_printf(m, "affinity: %*pbl\n", cpumask_pr_args(msk));
37 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
38 	msk = irq_data_get_effective_affinity_mask(data);
39 	seq_printf(m, "effectiv: %*pbl\n", cpumask_pr_args(msk));
40 #endif
41 #ifdef CONFIG_GENERIC_PENDING_IRQ
42 	msk = desc->pending_mask;
43 	seq_printf(m, "pending:  %*pbl\n", cpumask_pr_args(msk));
44 #endif
45 }
46 #else
47 static void irq_debug_show_masks(struct seq_file *m, struct irq_desc *desc) { }
48 #endif
49 
50 static const struct irq_bit_descr irqchip_flags[] = {
51 	BIT_MASK_DESCR(IRQCHIP_SET_TYPE_MASKED),
52 	BIT_MASK_DESCR(IRQCHIP_EOI_IF_HANDLED),
53 	BIT_MASK_DESCR(IRQCHIP_MASK_ON_SUSPEND),
54 	BIT_MASK_DESCR(IRQCHIP_ONOFFLINE_ENABLED),
55 	BIT_MASK_DESCR(IRQCHIP_SKIP_SET_WAKE),
56 	BIT_MASK_DESCR(IRQCHIP_ONESHOT_SAFE),
57 	BIT_MASK_DESCR(IRQCHIP_EOI_THREADED),
58 	BIT_MASK_DESCR(IRQCHIP_SUPPORTS_LEVEL_MSI),
59 	BIT_MASK_DESCR(IRQCHIP_SUPPORTS_NMI),
60 	BIT_MASK_DESCR(IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND),
61 	BIT_MASK_DESCR(IRQCHIP_IMMUTABLE),
62 };
63 
64 static void
65 irq_debug_show_chip(struct seq_file *m, struct irq_data *data, int ind)
66 {
67 	struct irq_chip *chip = data->chip;
68 
69 	if (!chip) {
70 		seq_printf(m, "chip: None\n");
71 		return;
72 	}
73 	seq_printf(m, "%*schip:    ", ind, "");
74 	if (chip->irq_print_chip)
75 		chip->irq_print_chip(data, m);
76 	else
77 		seq_printf(m, "%s", chip->name);
78 	seq_printf(m, "\n%*sflags:   0x%lx\n", ind + 1, "", chip->flags);
79 	irq_debug_show_bits(m, ind, chip->flags, irqchip_flags,
80 			    ARRAY_SIZE(irqchip_flags));
81 }
82 
83 static void
84 irq_debug_show_data(struct seq_file *m, struct irq_data *data, int ind)
85 {
86 	seq_printf(m, "%*sdomain:  %s\n", ind, "",
87 		   data->domain ? data->domain->name : "");
88 	seq_printf(m, "%*shwirq:   0x%lx\n", ind + 1, "", data->hwirq);
89 	irq_debug_show_chip(m, data, ind + 1);
90 	if (data->domain && data->domain->ops && data->domain->ops->debug_show)
91 		data->domain->ops->debug_show(m, NULL, data, ind + 1);
92 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
93 	if (!data->parent_data)
94 		return;
95 	seq_printf(m, "%*sparent:\n", ind + 1, "");
96 	irq_debug_show_data(m, data->parent_data, ind + 4);
97 #endif
98 }
99 
100 static const struct irq_bit_descr irqdata_states[] = {
101 	BIT_MASK_DESCR(IRQ_TYPE_EDGE_RISING),
102 	BIT_MASK_DESCR(IRQ_TYPE_EDGE_FALLING),
103 	BIT_MASK_DESCR(IRQ_TYPE_LEVEL_HIGH),
104 	BIT_MASK_DESCR(IRQ_TYPE_LEVEL_LOW),
105 	BIT_MASK_DESCR(IRQD_LEVEL),
106 
107 	BIT_MASK_DESCR(IRQD_ACTIVATED),
108 	BIT_MASK_DESCR(IRQD_IRQ_STARTED),
109 	BIT_MASK_DESCR(IRQD_IRQ_DISABLED),
110 	BIT_MASK_DESCR(IRQD_IRQ_MASKED),
111 	BIT_MASK_DESCR(IRQD_IRQ_INPROGRESS),
112 
113 	BIT_MASK_DESCR(IRQD_PER_CPU),
114 	BIT_MASK_DESCR(IRQD_NO_BALANCING),
115 
116 	BIT_MASK_DESCR(IRQD_SINGLE_TARGET),
117 	BIT_MASK_DESCR(IRQD_MOVE_PCNTXT),
118 	BIT_MASK_DESCR(IRQD_AFFINITY_SET),
119 	BIT_MASK_DESCR(IRQD_SETAFFINITY_PENDING),
120 	BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED),
121 	BIT_MASK_DESCR(IRQD_AFFINITY_ON_ACTIVATE),
122 	BIT_MASK_DESCR(IRQD_MANAGED_SHUTDOWN),
123 	BIT_MASK_DESCR(IRQD_CAN_RESERVE),
124 	BIT_MASK_DESCR(IRQD_MSI_NOMASK_QUIRK),
125 
126 	BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
127 
128 	BIT_MASK_DESCR(IRQD_WAKEUP_STATE),
129 	BIT_MASK_DESCR(IRQD_WAKEUP_ARMED),
130 
131 	BIT_MASK_DESCR(IRQD_DEFAULT_TRIGGER_SET),
132 
133 	BIT_MASK_DESCR(IRQD_HANDLE_ENFORCE_IRQCTX),
134 
135 	BIT_MASK_DESCR(IRQD_IRQ_ENABLED_ON_SUSPEND),
136 };
137 
138 static const struct irq_bit_descr irqdesc_states[] = {
139 	BIT_MASK_DESCR(_IRQ_NOPROBE),
140 	BIT_MASK_DESCR(_IRQ_NOREQUEST),
141 	BIT_MASK_DESCR(_IRQ_NOTHREAD),
142 	BIT_MASK_DESCR(_IRQ_NOAUTOEN),
143 	BIT_MASK_DESCR(_IRQ_NESTED_THREAD),
144 	BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID),
145 	BIT_MASK_DESCR(_IRQ_IS_POLLED),
146 	BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY),
147 	BIT_MASK_DESCR(_IRQ_HIDDEN),
148 };
149 
150 static const struct irq_bit_descr irqdesc_istates[] = {
151 	BIT_MASK_DESCR(IRQS_AUTODETECT),
152 	BIT_MASK_DESCR(IRQS_SPURIOUS_DISABLED),
153 	BIT_MASK_DESCR(IRQS_POLL_INPROGRESS),
154 	BIT_MASK_DESCR(IRQS_ONESHOT),
155 	BIT_MASK_DESCR(IRQS_REPLAY),
156 	BIT_MASK_DESCR(IRQS_WAITING),
157 	BIT_MASK_DESCR(IRQS_PENDING),
158 	BIT_MASK_DESCR(IRQS_SUSPENDED),
159 	BIT_MASK_DESCR(IRQS_NMI),
160 };
161 
162 
163 static int irq_debug_show(struct seq_file *m, void *p)
164 {
165 	struct irq_desc *desc = m->private;
166 	struct irq_data *data;
167 
168 	raw_spin_lock_irq(&desc->lock);
169 	data = irq_desc_get_irq_data(desc);
170 	seq_printf(m, "handler:  %ps\n", desc->handle_irq);
171 	seq_printf(m, "device:   %s\n", desc->dev_name);
172 	seq_printf(m, "status:   0x%08x\n", desc->status_use_accessors);
173 	irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states,
174 			    ARRAY_SIZE(irqdesc_states));
175 	seq_printf(m, "istate:   0x%08x\n", desc->istate);
176 	irq_debug_show_bits(m, 0, desc->istate, irqdesc_istates,
177 			    ARRAY_SIZE(irqdesc_istates));
178 	seq_printf(m, "ddepth:   %u\n", desc->depth);
179 	seq_printf(m, "wdepth:   %u\n", desc->wake_depth);
180 	seq_printf(m, "dstate:   0x%08x\n", irqd_get(data));
181 	irq_debug_show_bits(m, 0, irqd_get(data), irqdata_states,
182 			    ARRAY_SIZE(irqdata_states));
183 	seq_printf(m, "node:     %d\n", irq_data_get_node(data));
184 	irq_debug_show_masks(m, desc);
185 	irq_debug_show_data(m, data, 0);
186 	raw_spin_unlock_irq(&desc->lock);
187 	return 0;
188 }
189 
190 static int irq_debug_open(struct inode *inode, struct file *file)
191 {
192 	return single_open(file, irq_debug_show, inode->i_private);
193 }
194 
195 static ssize_t irq_debug_write(struct file *file, const char __user *user_buf,
196 			       size_t count, loff_t *ppos)
197 {
198 	struct irq_desc *desc = file_inode(file)->i_private;
199 	char buf[8] = { 0, };
200 	size_t size;
201 
202 	size = min(sizeof(buf) - 1, count);
203 	if (copy_from_user(buf, user_buf, size))
204 		return -EFAULT;
205 
206 	if (!strncmp(buf, "trigger", size)) {
207 		int err = irq_inject_interrupt(irq_desc_get_irq(desc));
208 
209 		return err ? err : count;
210 	}
211 
212 	return count;
213 }
214 
215 static const struct file_operations dfs_irq_ops = {
216 	.open		= irq_debug_open,
217 	.write		= irq_debug_write,
218 	.read		= seq_read,
219 	.llseek		= seq_lseek,
220 	.release	= single_release,
221 };
222 
223 void irq_debugfs_copy_devname(int irq, struct device *dev)
224 {
225 	struct irq_desc *desc = irq_to_desc(irq);
226 	const char *name = dev_name(dev);
227 
228 	if (name)
229 		desc->dev_name = kstrdup(name, GFP_KERNEL);
230 }
231 
232 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
233 {
234 	char name [10];
235 
236 	if (!irq_dir || !desc || desc->debugfs_file)
237 		return;
238 
239 	sprintf(name, "%d", irq);
240 	desc->debugfs_file = debugfs_create_file(name, 0644, irq_dir, desc,
241 						 &dfs_irq_ops);
242 }
243 
244 static int __init irq_debugfs_init(void)
245 {
246 	struct dentry *root_dir;
247 	int irq;
248 
249 	root_dir = debugfs_create_dir("irq", NULL);
250 
251 	irq_domain_debugfs_init(root_dir);
252 
253 	irq_dir = debugfs_create_dir("irqs", root_dir);
254 
255 	irq_lock_sparse();
256 	for_each_active_irq(irq)
257 		irq_add_debugfs_entry(irq, irq_to_desc(irq));
258 	irq_unlock_sparse();
259 
260 	return 0;
261 }
262 __initcall(irq_debugfs_init);
263