xref: /openbmc/linux/kernel/irq/debugfs.c (revision 11788d9b)
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 	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 };
61 
62 static void
63 irq_debug_show_chip(struct seq_file *m, struct irq_data *data, int ind)
64 {
65 	struct irq_chip *chip = data->chip;
66 
67 	if (!chip) {
68 		seq_printf(m, "chip: None\n");
69 		return;
70 	}
71 	seq_printf(m, "%*schip:    %s\n", ind, "", chip->name);
72 	seq_printf(m, "%*sflags:   0x%lx\n", ind + 1, "", chip->flags);
73 	irq_debug_show_bits(m, ind, chip->flags, irqchip_flags,
74 			    ARRAY_SIZE(irqchip_flags));
75 }
76 
77 static void
78 irq_debug_show_data(struct seq_file *m, struct irq_data *data, int ind)
79 {
80 	seq_printf(m, "%*sdomain:  %s\n", ind, "",
81 		   data->domain ? data->domain->name : "");
82 	seq_printf(m, "%*shwirq:   0x%lx\n", ind + 1, "", data->hwirq);
83 	irq_debug_show_chip(m, data, ind + 1);
84 	if (data->domain && data->domain->ops && data->domain->ops->debug_show)
85 		data->domain->ops->debug_show(m, NULL, data, ind + 1);
86 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
87 	if (!data->parent_data)
88 		return;
89 	seq_printf(m, "%*sparent:\n", ind + 1, "");
90 	irq_debug_show_data(m, data->parent_data, ind + 4);
91 #endif
92 }
93 
94 static const struct irq_bit_descr irqdata_states[] = {
95 	BIT_MASK_DESCR(IRQ_TYPE_EDGE_RISING),
96 	BIT_MASK_DESCR(IRQ_TYPE_EDGE_FALLING),
97 	BIT_MASK_DESCR(IRQ_TYPE_LEVEL_HIGH),
98 	BIT_MASK_DESCR(IRQ_TYPE_LEVEL_LOW),
99 	BIT_MASK_DESCR(IRQD_LEVEL),
100 
101 	BIT_MASK_DESCR(IRQD_ACTIVATED),
102 	BIT_MASK_DESCR(IRQD_IRQ_STARTED),
103 	BIT_MASK_DESCR(IRQD_IRQ_DISABLED),
104 	BIT_MASK_DESCR(IRQD_IRQ_MASKED),
105 	BIT_MASK_DESCR(IRQD_IRQ_INPROGRESS),
106 
107 	BIT_MASK_DESCR(IRQD_PER_CPU),
108 	BIT_MASK_DESCR(IRQD_NO_BALANCING),
109 
110 	BIT_MASK_DESCR(IRQD_SINGLE_TARGET),
111 	BIT_MASK_DESCR(IRQD_MOVE_PCNTXT),
112 	BIT_MASK_DESCR(IRQD_AFFINITY_SET),
113 	BIT_MASK_DESCR(IRQD_SETAFFINITY_PENDING),
114 	BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED),
115 	BIT_MASK_DESCR(IRQD_AFFINITY_ON_ACTIVATE),
116 	BIT_MASK_DESCR(IRQD_MANAGED_SHUTDOWN),
117 	BIT_MASK_DESCR(IRQD_CAN_RESERVE),
118 	BIT_MASK_DESCR(IRQD_MSI_NOMASK_QUIRK),
119 
120 	BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
121 
122 	BIT_MASK_DESCR(IRQD_WAKEUP_STATE),
123 	BIT_MASK_DESCR(IRQD_WAKEUP_ARMED),
124 
125 	BIT_MASK_DESCR(IRQD_DEFAULT_TRIGGER_SET),
126 
127 	BIT_MASK_DESCR(IRQD_HANDLE_ENFORCE_IRQCTX),
128 };
129 
130 static const struct irq_bit_descr irqdesc_states[] = {
131 	BIT_MASK_DESCR(_IRQ_NOPROBE),
132 	BIT_MASK_DESCR(_IRQ_NOREQUEST),
133 	BIT_MASK_DESCR(_IRQ_NOTHREAD),
134 	BIT_MASK_DESCR(_IRQ_NOAUTOEN),
135 	BIT_MASK_DESCR(_IRQ_NESTED_THREAD),
136 	BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID),
137 	BIT_MASK_DESCR(_IRQ_IS_POLLED),
138 	BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY),
139 };
140 
141 static const struct irq_bit_descr irqdesc_istates[] = {
142 	BIT_MASK_DESCR(IRQS_AUTODETECT),
143 	BIT_MASK_DESCR(IRQS_SPURIOUS_DISABLED),
144 	BIT_MASK_DESCR(IRQS_POLL_INPROGRESS),
145 	BIT_MASK_DESCR(IRQS_ONESHOT),
146 	BIT_MASK_DESCR(IRQS_REPLAY),
147 	BIT_MASK_DESCR(IRQS_WAITING),
148 	BIT_MASK_DESCR(IRQS_PENDING),
149 	BIT_MASK_DESCR(IRQS_SUSPENDED),
150 	BIT_MASK_DESCR(IRQS_NMI),
151 };
152 
153 
154 static int irq_debug_show(struct seq_file *m, void *p)
155 {
156 	struct irq_desc *desc = m->private;
157 	struct irq_data *data;
158 
159 	raw_spin_lock_irq(&desc->lock);
160 	data = irq_desc_get_irq_data(desc);
161 	seq_printf(m, "handler:  %ps\n", desc->handle_irq);
162 	seq_printf(m, "device:   %s\n", desc->dev_name);
163 	seq_printf(m, "status:   0x%08x\n", desc->status_use_accessors);
164 	irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states,
165 			    ARRAY_SIZE(irqdesc_states));
166 	seq_printf(m, "istate:   0x%08x\n", desc->istate);
167 	irq_debug_show_bits(m, 0, desc->istate, irqdesc_istates,
168 			    ARRAY_SIZE(irqdesc_istates));
169 	seq_printf(m, "ddepth:   %u\n", desc->depth);
170 	seq_printf(m, "wdepth:   %u\n", desc->wake_depth);
171 	seq_printf(m, "dstate:   0x%08x\n", irqd_get(data));
172 	irq_debug_show_bits(m, 0, irqd_get(data), irqdata_states,
173 			    ARRAY_SIZE(irqdata_states));
174 	seq_printf(m, "node:     %d\n", irq_data_get_node(data));
175 	irq_debug_show_masks(m, desc);
176 	irq_debug_show_data(m, data, 0);
177 	raw_spin_unlock_irq(&desc->lock);
178 	return 0;
179 }
180 
181 static int irq_debug_open(struct inode *inode, struct file *file)
182 {
183 	return single_open(file, irq_debug_show, inode->i_private);
184 }
185 
186 static ssize_t irq_debug_write(struct file *file, const char __user *user_buf,
187 			       size_t count, loff_t *ppos)
188 {
189 	struct irq_desc *desc = file_inode(file)->i_private;
190 	char buf[8] = { 0, };
191 	size_t size;
192 
193 	size = min(sizeof(buf) - 1, count);
194 	if (copy_from_user(buf, user_buf, size))
195 		return -EFAULT;
196 
197 	if (!strncmp(buf, "trigger", size)) {
198 		int err = irq_inject_interrupt(irq_desc_get_irq(desc));
199 
200 		return err ? err : count;
201 	}
202 
203 	return count;
204 }
205 
206 static const struct file_operations dfs_irq_ops = {
207 	.open		= irq_debug_open,
208 	.write		= irq_debug_write,
209 	.read		= seq_read,
210 	.llseek		= seq_lseek,
211 	.release	= single_release,
212 };
213 
214 void irq_debugfs_copy_devname(int irq, struct device *dev)
215 {
216 	struct irq_desc *desc = irq_to_desc(irq);
217 	const char *name = dev_name(dev);
218 
219 	if (name)
220 		desc->dev_name = kstrdup(name, GFP_KERNEL);
221 }
222 
223 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
224 {
225 	char name [10];
226 
227 	if (!irq_dir || !desc || desc->debugfs_file)
228 		return;
229 
230 	sprintf(name, "%d", irq);
231 	desc->debugfs_file = debugfs_create_file(name, 0644, irq_dir, desc,
232 						 &dfs_irq_ops);
233 }
234 
235 static int __init irq_debugfs_init(void)
236 {
237 	struct dentry *root_dir;
238 	int irq;
239 
240 	root_dir = debugfs_create_dir("irq", NULL);
241 
242 	irq_domain_debugfs_init(root_dir);
243 
244 	irq_dir = debugfs_create_dir("irqs", root_dir);
245 
246 	irq_lock_sparse();
247 	for_each_active_irq(irq)
248 		irq_add_debugfs_entry(irq, irq_to_desc(irq));
249 	irq_unlock_sparse();
250 
251 	return 0;
252 }
253 __initcall(irq_debugfs_init);
254