Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/irq/spurious.c |
| 3 | * |
| 4 | * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar |
| 5 | * |
| 6 | * This file contains spurious interrupt handling. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/irq.h> |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/kallsyms.h> |
| 12 | #include <linux/interrupt.h> |
| 13 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 14 | static int irqfixup; |
| 15 | |
| 16 | /* |
| 17 | * Recovery handler for misrouted interrupts. |
| 18 | */ |
| 19 | |
| 20 | static int misrouted_irq(int irq, struct pt_regs *regs) |
| 21 | { |
| 22 | int i; |
| 23 | irq_desc_t *desc; |
| 24 | int ok = 0; |
| 25 | int work = 0; /* Did we do work for a real IRQ */ |
| 26 | |
| 27 | for(i = 1; i < NR_IRQS; i++) { |
| 28 | struct irqaction *action; |
| 29 | |
| 30 | if (i == irq) /* Already tried */ |
| 31 | continue; |
| 32 | desc = &irq_desc[i]; |
| 33 | spin_lock(&desc->lock); |
| 34 | action = desc->action; |
| 35 | /* Already running on another processor */ |
| 36 | if (desc->status & IRQ_INPROGRESS) { |
| 37 | /* |
| 38 | * Already running: If it is shared get the other |
| 39 | * CPU to go looking for our mystery interrupt too |
| 40 | */ |
| 41 | if (desc->action && (desc->action->flags & SA_SHIRQ)) |
| 42 | desc->status |= IRQ_PENDING; |
| 43 | spin_unlock(&desc->lock); |
| 44 | continue; |
| 45 | } |
| 46 | /* Honour the normal IRQ locking */ |
| 47 | desc->status |= IRQ_INPROGRESS; |
| 48 | spin_unlock(&desc->lock); |
| 49 | while (action) { |
| 50 | /* Only shared IRQ handlers are safe to call */ |
| 51 | if (action->flags & SA_SHIRQ) { |
| 52 | if (action->handler(i, action->dev_id, regs) == |
| 53 | IRQ_HANDLED) |
| 54 | ok = 1; |
| 55 | } |
| 56 | action = action->next; |
| 57 | } |
| 58 | local_irq_disable(); |
| 59 | /* Now clean up the flags */ |
| 60 | spin_lock(&desc->lock); |
| 61 | action = desc->action; |
| 62 | |
| 63 | /* |
| 64 | * While we were looking for a fixup someone queued a real |
| 65 | * IRQ clashing with our walk |
| 66 | */ |
| 67 | |
| 68 | while ((desc->status & IRQ_PENDING) && action) { |
| 69 | /* |
| 70 | * Perform real IRQ processing for the IRQ we deferred |
| 71 | */ |
| 72 | work = 1; |
| 73 | spin_unlock(&desc->lock); |
| 74 | handle_IRQ_event(i, regs, action); |
| 75 | spin_lock(&desc->lock); |
| 76 | desc->status &= ~IRQ_PENDING; |
| 77 | } |
| 78 | desc->status &= ~IRQ_INPROGRESS; |
| 79 | /* |
| 80 | * If we did actual work for the real IRQ line we must let the |
| 81 | * IRQ controller clean up too |
| 82 | */ |
| 83 | if(work) |
| 84 | desc->handler->end(i); |
| 85 | spin_unlock(&desc->lock); |
| 86 | } |
| 87 | /* So the caller can adjust the irq error counts */ |
| 88 | return ok; |
| 89 | } |
| 90 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | /* |
| 92 | * If 99,900 of the previous 100,000 interrupts have not been handled |
| 93 | * then assume that the IRQ is stuck in some manner. Drop a diagnostic |
| 94 | * and try to turn the IRQ off. |
| 95 | * |
| 96 | * (The other 100-of-100,000 interrupts may have been a correctly |
| 97 | * functioning device sharing an IRQ with the failing one) |
| 98 | * |
| 99 | * Called under desc->lock |
| 100 | */ |
| 101 | |
| 102 | static void |
| 103 | __report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret) |
| 104 | { |
| 105 | struct irqaction *action; |
| 106 | |
| 107 | if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) { |
| 108 | printk(KERN_ERR "irq event %d: bogus return value %x\n", |
| 109 | irq, action_ret); |
| 110 | } else { |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 111 | printk(KERN_ERR "irq %d: nobody cared (try booting with " |
| 112 | "the \"irqpoll\" option)\n", irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | } |
| 114 | dump_stack(); |
| 115 | printk(KERN_ERR "handlers:\n"); |
| 116 | action = desc->action; |
| 117 | while (action) { |
| 118 | printk(KERN_ERR "[<%p>]", action->handler); |
| 119 | print_symbol(" (%s)", |
| 120 | (unsigned long)action->handler); |
| 121 | printk("\n"); |
| 122 | action = action->next; |
| 123 | } |
| 124 | } |
| 125 | |
Adrian Bunk | 52c1da3 | 2005-06-23 22:05:33 -0700 | [diff] [blame] | 126 | static void report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | { |
| 128 | static int count = 100; |
| 129 | |
| 130 | if (count > 0) { |
| 131 | count--; |
| 132 | __report_bad_irq(irq, desc, action_ret); |
| 133 | } |
| 134 | } |
| 135 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 136 | void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret, |
| 137 | struct pt_regs *regs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | { |
| 139 | if (action_ret != IRQ_HANDLED) { |
| 140 | desc->irqs_unhandled++; |
| 141 | if (action_ret != IRQ_NONE) |
| 142 | report_bad_irq(irq, desc, action_ret); |
| 143 | } |
| 144 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 145 | if (unlikely(irqfixup)) { |
| 146 | /* Don't punish working computers */ |
| 147 | if ((irqfixup == 2 && irq == 0) || action_ret == IRQ_NONE) { |
| 148 | int ok = misrouted_irq(irq, regs); |
| 149 | if (action_ret == IRQ_NONE) |
| 150 | desc->irqs_unhandled -= ok; |
| 151 | } |
| 152 | } |
| 153 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | desc->irq_count++; |
| 155 | if (desc->irq_count < 100000) |
| 156 | return; |
| 157 | |
| 158 | desc->irq_count = 0; |
| 159 | if (desc->irqs_unhandled > 99900) { |
| 160 | /* |
| 161 | * The interrupt is stuck |
| 162 | */ |
| 163 | __report_bad_irq(irq, desc, action_ret); |
| 164 | /* |
| 165 | * Now kill the IRQ |
| 166 | */ |
| 167 | printk(KERN_EMERG "Disabling IRQ #%d\n", irq); |
| 168 | desc->status |= IRQ_DISABLED; |
| 169 | desc->handler->disable(irq); |
| 170 | } |
| 171 | desc->irqs_unhandled = 0; |
| 172 | } |
| 173 | |
| 174 | int noirqdebug; |
| 175 | |
| 176 | int __init noirqdebug_setup(char *str) |
| 177 | { |
| 178 | noirqdebug = 1; |
| 179 | printk(KERN_INFO "IRQ lockup detection disabled\n"); |
| 180 | return 1; |
| 181 | } |
| 182 | |
| 183 | __setup("noirqdebug", noirqdebug_setup); |
| 184 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 185 | static int __init irqfixup_setup(char *str) |
| 186 | { |
| 187 | irqfixup = 1; |
| 188 | printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n"); |
| 189 | printk(KERN_WARNING "This may impact system performance.\n"); |
| 190 | return 1; |
| 191 | } |
| 192 | |
| 193 | __setup("irqfixup", irqfixup_setup); |
| 194 | |
| 195 | static int __init irqpoll_setup(char *str) |
| 196 | { |
| 197 | irqfixup = 2; |
| 198 | printk(KERN_WARNING "Misrouted IRQ fixup and polling support " |
| 199 | "enabled\n"); |
| 200 | printk(KERN_WARNING "This may significantly impact system " |
| 201 | "performance\n"); |
| 202 | return 1; |
| 203 | } |
| 204 | |
| 205 | __setup("irqpoll", irqpoll_setup); |