kernel/irq/debugfs.c

   1 /*
   2  * Copyright 2017 Thomas Gleixner <tglx@linutronix.de>
   3  *
   4  * This file is licensed under the GPL V2.
   5  */
   6 #include <linux/irqdomain.h>
   7 #include <linux/irq.h>
   8 #include <linux/uaccess.h>
   9
  10 #include "internals.h"
  11
  12 static struct dentry *irq_dir;
  13
  14 struct irq_bit_descr {
  15         unsigned int    mask;
  16         char            *name;
  17 };
  18 #define BIT_MASK_DESCR(m)       { .mask = m, .name = #m }
  19
  20 static void irq_debug_show_bits(struct seq_file *m, int ind, unsigned int state,
  21                                 const struct irq_bit_descr *sd, int size)
  22 {
  23         int i;
  24
  25         for (i = 0; i < size; i++, sd++) {
  26                 if (state & sd->mask)
  27                         seq_printf(m, "%*s%s\n", ind + 12, "", sd->name);
  28         }
  29 }
  30
  31 #ifdef CONFIG_SMP
  32 static void irq_debug_show_masks(struct seq_file *m, struct irq_desc *desc)
  33 {
  34         struct irq_data *data = irq_desc_get_irq_data(desc);
  35         struct cpumask *msk;
  36
  37         msk = irq_data_get_affinity_mask(data);
  38         seq_printf(m, "affinity: %*pbl\n", cpumask_pr_args(msk));
  39 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
  40         msk = irq_data_get_effective_affinity_mask(data);
  41         seq_printf(m, "effectiv: %*pbl\n", cpumask_pr_args(msk));
  42 #endif
  43 #ifdef CONFIG_GENERIC_PENDING_IRQ
  44         msk = desc->pending_mask;
  45         seq_printf(m, "pending:  %*pbl\n", cpumask_pr_args(msk));
  46 #endif
  47 }
  48 #else
  49 static void irq_debug_show_masks(struct seq_file *m, struct irq_desc *desc) { }
  50 #endif
  51
  52 static const struct irq_bit_descr irqchip_flags[] = {
  53         BIT_MASK_DESCR(IRQCHIP_SET_TYPE_MASKED),
  54         BIT_MASK_DESCR(IRQCHIP_EOI_IF_HANDLED),
  55         BIT_MASK_DESCR(IRQCHIP_MASK_ON_SUSPEND),
  56         BIT_MASK_DESCR(IRQCHIP_ONOFFLINE_ENABLED),
  57         BIT_MASK_DESCR(IRQCHIP_SKIP_SET_WAKE),
  58         BIT_MASK_DESCR(IRQCHIP_ONESHOT_SAFE),
  59         BIT_MASK_DESCR(IRQCHIP_EOI_THREADED),
  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_MANAGED_SHUTDOWN),
 116         BIT_MASK_DESCR(IRQD_CAN_RESERVE),
 117
 118         BIT_MASK_DESCR(IRQD_FORWARDED_TO_VCPU),
 119
 120         BIT_MASK_DESCR(IRQD_WAKEUP_STATE),
 121         BIT_MASK_DESCR(IRQD_WAKEUP_ARMED),
 122 };
 123
 124 static const struct irq_bit_descr irqdesc_states[] = {
 125         BIT_MASK_DESCR(_IRQ_NOPROBE),
 126         BIT_MASK_DESCR(_IRQ_NOREQUEST),
 127         BIT_MASK_DESCR(_IRQ_NOTHREAD),
 128         BIT_MASK_DESCR(_IRQ_NOAUTOEN),
 129         BIT_MASK_DESCR(_IRQ_NESTED_THREAD),
 130         BIT_MASK_DESCR(_IRQ_PER_CPU_DEVID),
 131         BIT_MASK_DESCR(_IRQ_IS_POLLED),
 132         BIT_MASK_DESCR(_IRQ_DISABLE_UNLAZY),
 133 };
 134
 135 static const struct irq_bit_descr irqdesc_istates[] = {
 136         BIT_MASK_DESCR(IRQS_AUTODETECT),
 137         BIT_MASK_DESCR(IRQS_SPURIOUS_DISABLED),
 138         BIT_MASK_DESCR(IRQS_POLL_INPROGRESS),
 139         BIT_MASK_DESCR(IRQS_ONESHOT),
 140         BIT_MASK_DESCR(IRQS_REPLAY),
 141         BIT_MASK_DESCR(IRQS_WAITING),
 142         BIT_MASK_DESCR(IRQS_PENDING),
 143         BIT_MASK_DESCR(IRQS_SUSPENDED),
 144 };
 145
 146
 147 static int irq_debug_show(struct seq_file *m, void *p)
 148 {
 149         struct irq_desc *desc = m->private;
 150         struct irq_data *data;
 151
 152         raw_spin_lock_irq(&desc->lock);
 153         data = irq_desc_get_irq_data(desc);
 154         seq_printf(m, "handler:  %pf\n", desc->handle_irq);
 155         seq_printf(m, "device:   %s\n", desc->dev_name);
 156         seq_printf(m, "status:   0x%08x\n", desc->status_use_accessors);
 157         irq_debug_show_bits(m, 0, desc->status_use_accessors, irqdesc_states,
 158                             ARRAY_SIZE(irqdesc_states));
 159         seq_printf(m, "istate:   0x%08x\n", desc->istate);
 160         irq_debug_show_bits(m, 0, desc->istate, irqdesc_istates,
 161                             ARRAY_SIZE(irqdesc_istates));
 162         seq_printf(m, "ddepth:   %u\n", desc->depth);
 163         seq_printf(m, "wdepth:   %u\n", desc->wake_depth);
 164         seq_printf(m, "dstate:   0x%08x\n", irqd_get(data));
 165         irq_debug_show_bits(m, 0, irqd_get(data), irqdata_states,
 166                             ARRAY_SIZE(irqdata_states));
 167         seq_printf(m, "node:     %d\n", irq_data_get_node(data));
 168         irq_debug_show_masks(m, desc);
 169         irq_debug_show_data(m, data, 0);
 170         raw_spin_unlock_irq(&desc->lock);
 171         return 0;
 172 }
 173
 174 static int irq_debug_open(struct inode *inode, struct file *file)
 175 {
 176         return single_open(file, irq_debug_show, inode->i_private);
 177 }
 178
 179 static ssize_t irq_debug_write(struct file *file, const char __user *user_buf,
 180                                size_t count, loff_t *ppos)
 181 {
 182         struct irq_desc *desc = file_inode(file)->i_private;
 183         char buf[8] = { 0, };
 184         size_t size;
 185
 186         size = min(sizeof(buf) - 1, count);
 187         if (copy_from_user(buf, user_buf, size))
 188                 return -EFAULT;
 189
 190         if (!strncmp(buf, "trigger", size)) {
 191                 unsigned long flags;
 192                 int err;
 193
 194                 /* Try the HW interface first */
 195                 err = irq_set_irqchip_state(irq_desc_get_irq(desc),
 196                                             IRQCHIP_STATE_PENDING, true);
 197                 if (!err)
 198                         return count;
 199
 200                 /*
 201                  * Otherwise, try to inject via the resend interface,
 202                  * which may or may not succeed.
 203                  */
 204                 chip_bus_lock(desc);
 205                 raw_spin_lock_irqsave(&desc->lock, flags);
 206
 207                 if (irq_settings_is_level(desc)) {
 208                         /* Can't do level, sorry */
 209                         err = -EINVAL;
 210                 } else {
 211                         desc->istate |= IRQS_PENDING;
 212                         check_irq_resend(desc);
 213                         err = 0;
 214                 }
 215
 216                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 217                 chip_bus_sync_unlock(desc);
 218
 219                 return err ? err : count;
 220         }
 221
 222         return count;
 223 }
 224
 225 static const struct file_operations dfs_irq_ops = {
 226         .open           = irq_debug_open,
 227         .write          = irq_debug_write,
 228         .read           = seq_read,
 229         .llseek         = seq_lseek,
 230         .release        = single_release,
 231 };
 232
 233 void irq_debugfs_copy_devname(int irq, struct device *dev)
 234 {
 235         struct irq_desc *desc = irq_to_desc(irq);
 236         const char *name = dev_name(dev);
 237
 238         if (name)
 239                 desc->dev_name = kstrdup(name, GFP_KERNEL);
 240 }
 241
 242 void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
 243 {
 244         char name [10];
 245
 246         if (!irq_dir || !desc || desc->debugfs_file)
 247                 return;
 248
 249         sprintf(name, "%d", irq);
 250         desc->debugfs_file = debugfs_create_file(name, 0644, irq_dir, desc,
 251                                                  &dfs_irq_ops);
 252 }
 253
 254 static int __init irq_debugfs_init(void)
 255 {
 256         struct dentry *root_dir;
 257         int irq;
 258
 259         root_dir = debugfs_create_dir("irq", NULL);
 260         if (!root_dir)
 261                 return -ENOMEM;
 262
 263         irq_domain_debugfs_init(root_dir);
 264
 265         irq_dir = debugfs_create_dir("irqs", root_dir);
 266
 267         irq_lock_sparse();
 268         for_each_active_irq(irq)
 269                 irq_add_debugfs_entry(irq, irq_to_desc(irq));
 270         irq_unlock_sparse();
 271
 272         return 0;
 273 }
 274 __initcall(irq_debugfs_init);