kernel/irq/debugfs.c

   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 };
  59
  60 static void
  61 irq_debug_show_chip(struct seq_file *m, struct irq_data *data, int ind)
  62 {
  63         struct irq_chip *chip = data->chip;
  64
  65         if (!chip) {
  66                 seq_printf(m, "chip: None\n");
  67                 return;
  68         }
  69         seq_printf(m, "%*schip:    %s\n", ind, "", chip->name);
  70         seq_printf(m, "%*sflags:   0x%lx\n", ind + 1, "", chip->flags);
  71         irq_debug_show_bits(m, ind, chip->flags, irqchip_flags,
  72                             ARRAY_SIZE(irqchip_flags));
  73 }
  74
  75 static void
  76 irq_debug_show_data(struct seq_file *m, struct irq_data *data, int ind)
  77 {
  78         seq_printf(m, "%*sdomain:  %s\n", ind, "",
  79                    data->domain ? data->domain->name : "");
  80         seq_printf(m, "%*shwirq:   0x%lx\n", ind + 1, "", data->hwirq);
  81         irq_debug_show_chip(m, data, ind + 1);
  82         if (data->domain && data->domain->ops && data->domain->ops->debug_show)
  83                 data->domain->ops->debug_show(m, NULL, data, ind + 1);
  84 #ifdef  CONFIG_IRQ_DOMAIN_HIERARCHY
  85         if (!data->parent_data)
  86                 return;
  87         seq_printf(m, "%*sparent:\n", ind + 1, "");
  88         irq_debug_show_data(m, data->parent_data, ind + 4);
  89 #endif
  90 }
  91
  92 static const struct irq_bit_descr irqdata_states[] = {
  93         BIT_MASK_DESCR(IRQ_TYPE_EDGE_RISING),
  94         BIT_MASK_DESCR(IRQ_TYPE_EDGE_FALLING),
  95         BIT_MASK_DESCR(IRQ_TYPE_LEVEL_HIGH),
  96         BIT_MASK_DESCR(IRQ_TYPE_LEVEL_LOW),
  97         BIT_MASK_DESCR(IRQD_LEVEL),
  98
  99         BIT_MASK_DESCR(IRQD_ACTIVATED),
 100         BIT_MASK_DESCR(IRQD_IRQ_STARTED),
 101         BIT_MASK_DESCR(IRQD_IRQ_DISABLED),
 102         BIT_MASK_DESCR(IRQD_IRQ_MASKED),
 103         BIT_MASK_DESCR(IRQD_IRQ_INPROGRESS),
 104
 105         BIT_MASK_DESCR(IRQD_PER_CPU),
 106         BIT_MASK_DESCR(IRQD_NO_BALANCING),
 107
 108         BIT_MASK_DESCR(IRQD_SINGLE_TARGET),
 109         BIT_MASK_DESCR(IRQD_MOVE_PCNTXT),
 110         BIT_MASK_DESCR(IRQD_AFFINITY_SET),
 111         BIT_MASK_DESCR(IRQD_SETAFFINITY_PENDING),
 112         BIT_MASK_DESCR(IRQD_AFFINITY_MANAGED),
 113         BIT_MASK_DESCR(IRQD_MANAGED_SHUTDOWN),
 114         BIT_MASK_DESCR(IRQD_CAN_RESERVE),
 115
 116         BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
 117
 118         BIT_MASK_DESCR(IRQD_WAKEUP_STATE),
 119         BIT_MASK_DESCR(IRQD_WAKEUP_ARMED),
 120 };
 121
 122 static const struct irq_bit_descr irqdesc_states[] = {
 123         BIT_MASK_DESCR(_IRQ_NOPROBE),
 124         BIT_MASK_DESCR(_IRQ_NOREQUEST),
 125         BIT_MASK_DESCR(_IRQ_NOTHREAD),
 126         BIT_MASK_DESCR(_IRQ_NOAUTOEN),
 127         BIT_MASK_DESCR(_IRQ_NESTED_THREAD),
 128         BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID),
 129         BIT_MASK_DESCR(_IRQ_IS_POLLED),
 130         BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY),
 131 };
 132
 133 static const struct irq_bit_descr irqdesc_istates[] = {
 134         BIT_MASK_DESCR(IRQS_AUTODETECT),
 135         BIT_MASK_DESCR(IRQS_SPURIOUS_DISABLED),
 136         BIT_MASK_DESCR(IRQS_POLL_INPROGRESS),
 137         BIT_MASK_DESCR(IRQS_ONESHOT),
 138         BIT_MASK_DESCR(IRQS_REPLAY),
 139         BIT_MASK_DESCR(IRQS_WAITING),
 140         BIT_MASK_DESCR(IRQS_PENDING),
 141         BIT_MASK_DESCR(IRQS_SUSPENDED),
 142 };
 143
 144
 145 static int irq_debug_show(struct seq_file *m, void *p)
 146 {
 147         struct irq_desc *desc = m->private;
 148         struct irq_data *data;
 149
 150         raw_spin_lock_irq(&desc->lock);
 151         data = irq_desc_get_irq_data(desc);
 152         seq_printf(m, "handler:  %pf\n", desc->handle_irq);
 153         seq_printf(m, "device:   %s\n", desc->dev_name);
 154         seq_printf(m, "status:   0x%08x\n", desc->status_use_accessors);
 155         irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states,
 156                             ARRAY_SIZE(irqdesc_states));
 157         seq_printf(m, "istate:   0x%08x\n", desc->istate);
 158         irq_debug_show_bits(m, 0, desc->istate, irqdesc_istates,
 159                             ARRAY_SIZE(irqdesc_istates));
 160         seq_printf(m, "ddepth:   %u\n", desc->depth);
 161         seq_printf(m, "wdepth:   %u\n", desc->wake_depth);
 162         seq_printf(m, "dstate:   0x%08x\n", irqd_get(data));
 163         irq_debug_show_bits(m, 0, irqd_get(data), irqdata_states,
 164                             ARRAY_SIZE(irqdata_states));
 165         seq_printf(m, "node:     %d\n", irq_data_get_node(data));
 166         irq_debug_show_masks(m, desc);
 167         irq_debug_show_data(m, data, 0);
 168         raw_spin_unlock_irq(&desc->lock);
 169         return 0;
 170 }
 171
 172 static int irq_debug_open(struct inode *inode, struct file *file)
 173 {
 174         return single_open(file, irq_debug_show, inode->i_private);
 175 }
 176
 177 static ssize_t irq_debug_write(struct file *file, const char __user *user_buf,
 178                                size_t count, loff_t *ppos)
 179 {
 180         struct irq_desc *desc = file_inode(file)->i_private;
 181         char buf[8] = { 0, };
 182         size_t size;
 183
 184         size = min(sizeof(buf) - 1, count);
 185         if (copy_from_user(buf, user_buf, size))
 186                 return -EFAULT;
 187
 188         if (!strncmp(buf, "trigger", size)) {
 189                 unsigned long flags;
 190                 int err;
 191
 192                 /* Try the HW interface first */
 193                 err = irq_set_irqchip_state(irq_desc_get_irq(desc),
 194                                             IRQCHIP_STATE_PENDING, true);
 195                 if (!err)
 196                         return count;
 197
 198                 /*
 199                  * Otherwise, try to inject via the resend interface,
 200                  * which may or may not succeed.
 201                  */
 202                 chip_bus_lock(desc);
 203                 raw_spin_lock_irqsave(&desc->lock, flags);
 204
 205                 if (irq_settings_is_level(desc)) {
 206                         /* Can't do level, sorry */
 207                         err = -EINVAL;
 208                 } else {
 209                         desc->istate |= IRQS_PENDING;
 210                         check_irq_resend(desc);
 211                         err = 0;
 212                 }
 213
 214                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 215                 chip_bus_sync_unlock(desc);
 216
 217                 return err ? err : count;
 218         }
 219
 220         return count;
 221 }
 222
 223 static const struct file_operations dfs_irq_ops = {
 224         .open           = irq_debug_open,
 225         .write          = irq_debug_write,
 226         .read           = seq_read,
 227         .llseek         = seq_lseek,
 228         .release        = single_release,
 229 };
 230
 231 void irq_debugfs_copy_devname(int irq, struct device *dev)
 232 {
 233         struct irq_desc *desc = irq_to_desc(irq);
 234         const char *name = dev_name(dev);
 235
 236         if (name)
 237                 desc->dev_name = kstrdup(name, GFP_KERNEL);
 238 }
 239
 240 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
 241 {
 242         char name [10];
 243
 244         if (!irq_dir || !desc || desc->debugfs_file)
 245                 return;
 246
 247         sprintf(name, "%d", irq);
 248         desc->debugfs_file = debugfs_create_file(name, 0644, irq_dir, desc,
 249                                                  &dfs_irq_ops);
 250 }
 251
 252 static int __init irq_debugfs_init(void)
 253 {
 254         struct dentry *root_dir;
 255         int irq;
 256
 257         root_dir = debugfs_create_dir("irq", NULL);
 258         if (!root_dir)
 259                 return -ENOMEM;
 260
 261         irq_domain_debugfs_init(root_dir);
 262
 263         irq_dir = debugfs_create_dir("irqs", root_dir);
 264
 265         irq_lock_sparse();
 266         for_each_active_irq(irq)
 267                 irq_add_debugfs_entry(irq, irq_to_desc(irq));
 268         irq_unlock_sparse();
 269
 270         return 0;
 271 }
 272 __initcall(irq_debugfs_init);