xref: /openbmc/linux/kernel/irq/debugfs.c (revision b4e18b29)
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 	BIT_MASK_DESCR(IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND),
61 };
62 
63 static void
64 irq_debug_show_chip(struct seq_file *m, struct irq_data *data, int ind)
65 {
66 	struct irq_chip *chip = data->chip;
67 
68 	if (!chip) {
69 		seq_printf(m, "chip: None\n");
70 		return;
71 	}
72 	seq_printf(m, "%*schip:    %s\n", ind, "", chip->name);
73 	seq_printf(m, "%*sflags:   0x%lx\n", ind + 1, "", chip->flags);
74 	irq_debug_show_bits(m, ind, chip->flags, irqchip_flags,
75 			    ARRAY_SIZE(irqchip_flags));
76 }
77 
78 static void
79 irq_debug_show_data(struct seq_file *m, struct irq_data *data, int ind)
80 {
81 	seq_printf(m, "%*sdomain:  %s\n", ind, "",
82 		   data->domain ? data->domain->name : "");
83 	seq_printf(m, "%*shwirq:   0x%lx\n", ind + 1, "", data->hwirq);
84 	irq_debug_show_chip(m, data, ind + 1);
85 	if (data->domain && data->domain->ops && data->domain->ops->debug_show)
86 		data->domain->ops->debug_show(m, NULL, data, ind + 1);
87 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
88 	if (!data->parent_data)
89 		return;
90 	seq_printf(m, "%*sparent:\n", ind + 1, "");
91 	irq_debug_show_data(m, data->parent_data, ind + 4);
92 #endif
93 }
94 
95 static const struct irq_bit_descr irqdata_states[] = {
96 	BIT_MASK_DESCR(IRQ_TYPE_EDGE_RISING),
97 	BIT_MASK_DESCR(IRQ_TYPE_EDGE_FALLING),
98 	BIT_MASK_DESCR(IRQ_TYPE_LEVEL_HIGH),
99 	BIT_MASK_DESCR(IRQ_TYPE_LEVEL_LOW),
100 	BIT_MASK_DESCR(IRQD_LEVEL),
101 
102 	BIT_MASK_DESCR(IRQD_ACTIVATED),
103 	BIT_MASK_DESCR(IRQD_IRQ_STARTED),
104 	BIT_MASK_DESCR(IRQD_IRQ_DISABLED),
105 	BIT_MASK_DESCR(IRQD_IRQ_MASKED),
106 	BIT_MASK_DESCR(IRQD_IRQ_INPROGRESS),
107 
108 	BIT_MASK_DESCR(IRQD_PER_CPU),
109 	BIT_MASK_DESCR(IRQD_NO_BALANCING),
110 
111 	BIT_MASK_DESCR(IRQD_SINGLE_TARGET),
112 	BIT_MASK_DESCR(IRQD_MOVE_PCNTXT),
113 	BIT_MASK_DESCR(IRQD_AFFINITY_SET),
114 	BIT_MASK_DESCR(IRQD_SETAFFINITY_PENDING),
115 	BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED),
116 	BIT_MASK_DESCR(IRQD_AFFINITY_ON_ACTIVATE),
117 	BIT_MASK_DESCR(IRQD_MANAGED_SHUTDOWN),
118 	BIT_MASK_DESCR(IRQD_CAN_RESERVE),
119 	BIT_MASK_DESCR(IRQD_MSI_NOMASK_QUIRK),
120 
121 	BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
122 
123 	BIT_MASK_DESCR(IRQD_WAKEUP_STATE),
124 	BIT_MASK_DESCR(IRQD_WAKEUP_ARMED),
125 
126 	BIT_MASK_DESCR(IRQD_DEFAULT_TRIGGER_SET),
127 
128 	BIT_MASK_DESCR(IRQD_HANDLE_ENFORCE_IRQCTX),
129 
130 	BIT_MASK_DESCR(IRQD_IRQ_ENABLED_ON_SUSPEND),
131 };
132 
133 static const struct irq_bit_descr irqdesc_states[] = {
134 	BIT_MASK_DESCR(_IRQ_NOPROBE),
135 	BIT_MASK_DESCR(_IRQ_NOREQUEST),
136 	BIT_MASK_DESCR(_IRQ_NOTHREAD),
137 	BIT_MASK_DESCR(_IRQ_NOAUTOEN),
138 	BIT_MASK_DESCR(_IRQ_NESTED_THREAD),
139 	BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID),
140 	BIT_MASK_DESCR(_IRQ_IS_POLLED),
141 	BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY),
142 	BIT_MASK_DESCR(_IRQ_HIDDEN),
143 };
144 
145 static const struct irq_bit_descr irqdesc_istates[] = {
146 	BIT_MASK_DESCR(IRQS_AUTODETECT),
147 	BIT_MASK_DESCR(IRQS_SPURIOUS_DISABLED),
148 	BIT_MASK_DESCR(IRQS_POLL_INPROGRESS),
149 	BIT_MASK_DESCR(IRQS_ONESHOT),
150 	BIT_MASK_DESCR(IRQS_REPLAY),
151 	BIT_MASK_DESCR(IRQS_WAITING),
152 	BIT_MASK_DESCR(IRQS_PENDING),
153 	BIT_MASK_DESCR(IRQS_SUSPENDED),
154 	BIT_MASK_DESCR(IRQS_NMI),
155 };
156 
157 
158 static int irq_debug_show(struct seq_file *m, void *p)
159 {
160 	struct irq_desc *desc = m->private;
161 	struct irq_data *data;
162 
163 	raw_spin_lock_irq(&desc->lock);
164 	data = irq_desc_get_irq_data(desc);
165 	seq_printf(m, "handler:  %ps\n", desc->handle_irq);
166 	seq_printf(m, "device:   %s\n", desc->dev_name);
167 	seq_printf(m, "status:   0x%08x\n", desc->status_use_accessors);
168 	irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states,
169 			    ARRAY_SIZE(irqdesc_states));
170 	seq_printf(m, "istate:   0x%08x\n", desc->istate);
171 	irq_debug_show_bits(m, 0, desc->istate, irqdesc_istates,
172 			    ARRAY_SIZE(irqdesc_istates));
173 	seq_printf(m, "ddepth:   %u\n", desc->depth);
174 	seq_printf(m, "wdepth:   %u\n", desc->wake_depth);
175 	seq_printf(m, "dstate:   0x%08x\n", irqd_get(data));
176 	irq_debug_show_bits(m, 0, irqd_get(data), irqdata_states,
177 			    ARRAY_SIZE(irqdata_states));
178 	seq_printf(m, "node:     %d\n", irq_data_get_node(data));
179 	irq_debug_show_masks(m, desc);
180 	irq_debug_show_data(m, data, 0);
181 	raw_spin_unlock_irq(&desc->lock);
182 	return 0;
183 }
184 
185 static int irq_debug_open(struct inode *inode, struct file *file)
186 {
187 	return single_open(file, irq_debug_show, inode->i_private);
188 }
189 
190 static ssize_t irq_debug_write(struct file *file, const char __user *user_buf,
191 			       size_t count, loff_t *ppos)
192 {
193 	struct irq_desc *desc = file_inode(file)->i_private;
194 	char buf[8] = { 0, };
195 	size_t size;
196 
197 	size = min(sizeof(buf) - 1, count);
198 	if (copy_from_user(buf, user_buf, size))
199 		return -EFAULT;
200 
201 	if (!strncmp(buf, "trigger", size)) {
202 		int err = irq_inject_interrupt(irq_desc_get_irq(desc));
203 
204 		return err ? err : count;
205 	}
206 
207 	return count;
208 }
209 
210 static const struct file_operations dfs_irq_ops = {
211 	.open		= irq_debug_open,
212 	.write		= irq_debug_write,
213 	.read		= seq_read,
214 	.llseek		= seq_lseek,
215 	.release	= single_release,
216 };
217 
218 void irq_debugfs_copy_devname(int irq, struct device *dev)
219 {
220 	struct irq_desc *desc = irq_to_desc(irq);
221 	const char *name = dev_name(dev);
222 
223 	if (name)
224 		desc->dev_name = kstrdup(name, GFP_KERNEL);
225 }
226 
227 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
228 {
229 	char name [10];
230 
231 	if (!irq_dir || !desc || desc->debugfs_file)
232 		return;
233 
234 	sprintf(name, "%d", irq);
235 	desc->debugfs_file = debugfs_create_file(name, 0644, irq_dir, desc,
236 						 &dfs_irq_ops);
237 }
238 
239 static int __init irq_debugfs_init(void)
240 {
241 	struct dentry *root_dir;
242 	int irq;
243 
244 	root_dir = debugfs_create_dir("irq", NULL);
245 
246 	irq_domain_debugfs_init(root_dir);
247 
248 	irq_dir = debugfs_create_dir("irqs", root_dir);
249 
250 	irq_lock_sparse();
251 	for_each_active_irq(irq)
252 		irq_add_debugfs_entry(irq, irq_to_desc(irq));
253 	irq_unlock_sparse();
254 
255 	return 0;
256 }
257 __initcall(irq_debugfs_init);
258