diff options
Diffstat (limited to 'arch/alpha/kernel/irq.c')
-rw-r--r-- | arch/alpha/kernel/irq.c | 630 |
1 files changed, 9 insertions, 621 deletions
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c index b6114f5c0d2..76be5cf0de1 100644 --- a/arch/alpha/kernel/irq.c +++ b/arch/alpha/kernel/irq.c @@ -32,214 +32,25 @@ #include <asm/io.h> #include <asm/uaccess.h> -/* - * Controller mappings for all interrupt sources: - */ -irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = { - [0 ... NR_IRQS-1] = { - .handler = &no_irq_type, - .lock = SPIN_LOCK_UNLOCKED - } -}; - -static void register_irq_proc(unsigned int irq); - volatile unsigned long irq_err_count; -/* - * Special irq handlers. - */ - -irqreturn_t no_action(int cpl, void *dev_id, struct pt_regs *regs) -{ - return IRQ_NONE; -} - -/* - * Generic no controller code - */ - -static void no_irq_enable_disable(unsigned int irq) { } -static unsigned int no_irq_startup(unsigned int irq) { return 0; } - -static void -no_irq_ack(unsigned int irq) +void ack_bad_irq(unsigned int irq) { irq_err_count++; printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq); } -struct hw_interrupt_type no_irq_type = { - .typename = "none", - .startup = no_irq_startup, - .shutdown = no_irq_enable_disable, - .enable = no_irq_enable_disable, - .disable = no_irq_enable_disable, - .ack = no_irq_ack, - .end = no_irq_enable_disable, -}; - -int -handle_IRQ_event(unsigned int irq, struct pt_regs *regs, - struct irqaction *action) -{ - int status = 1; /* Force the "do bottom halves" bit */ - int ret; - - do { - if (!(action->flags & SA_INTERRUPT)) - local_irq_enable(); - else - local_irq_disable(); - - ret = action->handler(irq, action->dev_id, regs); - if (ret == IRQ_HANDLED) - status |= action->flags; - action = action->next; - } while (action); - if (status & SA_SAMPLE_RANDOM) - add_interrupt_randomness(irq); - local_irq_disable(); - - return status; -} - -/* - * Generic enable/disable code: this just calls - * down into the PIC-specific version for the actual - * hardware disable after having gotten the irq - * controller lock. - */ -void inline -disable_irq_nosync(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - unsigned long flags; - - spin_lock_irqsave(&desc->lock, flags); - if (!desc->depth++) { - desc->status |= IRQ_DISABLED; - desc->handler->disable(irq); - } - spin_unlock_irqrestore(&desc->lock, flags); -} - -/* - * Synchronous version of the above, making sure the IRQ is - * no longer running on any other IRQ.. - */ -void -disable_irq(unsigned int irq) -{ - disable_irq_nosync(irq); - synchronize_irq(irq); -} - -void -enable_irq(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - unsigned long flags; - - spin_lock_irqsave(&desc->lock, flags); - switch (desc->depth) { - case 1: { - unsigned int status = desc->status & ~IRQ_DISABLED; - desc->status = status; - if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) { - desc->status = status | IRQ_REPLAY; - hw_resend_irq(desc->handler,irq); - } - desc->handler->enable(irq); - /* fall-through */ - } - default: - desc->depth--; - break; - case 0: - printk(KERN_ERR "enable_irq() unbalanced from %p\n", - __builtin_return_address(0)); - } - spin_unlock_irqrestore(&desc->lock, flags); -} - -int -setup_irq(unsigned int irq, struct irqaction * new) -{ - int shared = 0; - struct irqaction *old, **p; - unsigned long flags; - irq_desc_t *desc = irq_desc + irq; - - if (desc->handler == &no_irq_type) - return -ENOSYS; - - /* - * Some drivers like serial.c use request_irq() heavily, - * so we have to be careful not to interfere with a - * running system. - */ - if (new->flags & SA_SAMPLE_RANDOM) { - /* - * This function might sleep, we want to call it first, - * outside of the atomic block. - * Yes, this might clear the entropy pool if the wrong - * driver is attempted to be loaded, without actually - * installing a new handler, but is this really a problem, - * only the sysadmin is able to do this. - */ - rand_initialize_irq(irq); - } - - /* - * The following block of code has to be executed atomically - */ - spin_lock_irqsave(&desc->lock,flags); - p = &desc->action; - if ((old = *p) != NULL) { - /* Can't share interrupts unless both agree to */ - if (!(old->flags & new->flags & SA_SHIRQ)) { - spin_unlock_irqrestore(&desc->lock,flags); - return -EBUSY; - } - - /* add new interrupt at end of irq queue */ - do { - p = &old->next; - old = *p; - } while (old); - shared = 1; - } - - *p = new; - - if (!shared) { - desc->depth = 0; - desc->status &= - ~(IRQ_DISABLED|IRQ_AUTODETECT|IRQ_WAITING|IRQ_INPROGRESS); - desc->handler->startup(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - - return 0; -} - -static struct proc_dir_entry * root_irq_dir; -static struct proc_dir_entry * irq_dir[NR_IRQS]; - #ifdef CONFIG_SMP -static struct proc_dir_entry * smp_affinity_entry[NR_IRQS]; static char irq_user_affinity[NR_IRQS]; -static cpumask_t irq_affinity[NR_IRQS] = { [0 ... NR_IRQS-1] = CPU_MASK_ALL }; -static void -select_smp_affinity(int irq) +int +select_smp_affinity(unsigned int irq) { static int last_cpu; int cpu = last_cpu + 1; - if (! irq_desc[irq].handler->set_affinity || irq_user_affinity[irq]) - return; + if (!irq_desc[irq].handler->set_affinity || irq_user_affinity[irq]) + return 1; while (!cpu_possible(cpu)) cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0); @@ -247,208 +58,10 @@ select_smp_affinity(int irq) irq_affinity[irq] = cpumask_of_cpu(cpu); irq_desc[irq].handler->set_affinity(irq, cpumask_of_cpu(cpu)); + return 0; } - -static int -irq_affinity_read_proc (char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]); - if (count - len < 2) - return -EINVAL; - len += sprintf(page + len, "\n"); - return len; -} - -static int -irq_affinity_write_proc(struct file *file, const char __user *buffer, - unsigned long count, void *data) -{ - int irq = (long) data, full_count = count, err; - cpumask_t new_value; - - if (!irq_desc[irq].handler->set_affinity) - return -EIO; - - err = cpumask_parse(buffer, count, new_value); - - /* The special value 0 means release control of the - affinity to kernel. */ - cpus_and(new_value, new_value, cpu_online_map); - if (cpus_empty(new_value)) { - irq_user_affinity[irq] = 0; - select_smp_affinity(irq); - } - /* Do not allow disabling IRQs completely - it's a too easy - way to make the system unusable accidentally :-) At least - one online CPU still has to be targeted. */ - else { - irq_affinity[irq] = new_value; - irq_user_affinity[irq] = 1; - irq_desc[irq].handler->set_affinity(irq, new_value); - } - - return full_count; -} - #endif /* CONFIG_SMP */ -#define MAX_NAMELEN 10 - -static void -register_irq_proc (unsigned int irq) -{ - char name [MAX_NAMELEN]; - - if (!root_irq_dir || (irq_desc[irq].handler == &no_irq_type) || - irq_dir[irq]) - return; - - memset(name, 0, MAX_NAMELEN); - sprintf(name, "%d", irq); - - /* create /proc/irq/1234 */ - irq_dir[irq] = proc_mkdir(name, root_irq_dir); - -#ifdef CONFIG_SMP - if (irq_desc[irq].handler->set_affinity) { - struct proc_dir_entry *entry; - /* create /proc/irq/1234/smp_affinity */ - entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); - - if (entry) { - entry->nlink = 1; - entry->data = (void *)(long)irq; - entry->read_proc = irq_affinity_read_proc; - entry->write_proc = irq_affinity_write_proc; - } - - smp_affinity_entry[irq] = entry; - } -#endif -} - -void -init_irq_proc (void) -{ - int i; - - /* create /proc/irq */ - root_irq_dir = proc_mkdir("irq", NULL); - -#ifdef CONFIG_SMP - /* create /proc/irq/prof_cpu_mask */ - create_prof_cpu_mask(root_irq_dir); -#endif - - /* - * Create entries for all existing IRQs. - */ - for (i = 0; i < ACTUAL_NR_IRQS; i++) { - if (irq_desc[i].handler == &no_irq_type) - continue; - register_irq_proc(i); - } -} - -int -request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *), - unsigned long irqflags, const char * devname, void *dev_id) -{ - int retval; - struct irqaction * action; - - if (irq >= ACTUAL_NR_IRQS) - return -EINVAL; - if (!handler) - return -EINVAL; - -#if 1 - /* - * Sanity-check: shared interrupts should REALLY pass in - * a real dev-ID, otherwise we'll have trouble later trying - * to figure out which interrupt is which (messes up the - * interrupt freeing logic etc). - */ - if ((irqflags & SA_SHIRQ) && !dev_id) { - printk(KERN_ERR - "Bad boy: %s (at %p) called us without a dev_id!\n", - devname, __builtin_return_address(0)); - } -#endif - - action = (struct irqaction *) - kmalloc(sizeof(struct irqaction), GFP_KERNEL); - if (!action) - return -ENOMEM; - - action->handler = handler; - action->flags = irqflags; - cpus_clear(action->mask); - action->name = devname; - action->next = NULL; - action->dev_id = dev_id; - -#ifdef CONFIG_SMP - select_smp_affinity(irq); -#endif - - retval = setup_irq(irq, action); - if (retval) - kfree(action); - return retval; -} - -EXPORT_SYMBOL(request_irq); - -void -free_irq(unsigned int irq, void *dev_id) -{ - irq_desc_t *desc; - struct irqaction **p; - unsigned long flags; - - if (irq >= ACTUAL_NR_IRQS) { - printk(KERN_CRIT "Trying to free IRQ%d\n", irq); - return; - } - - desc = irq_desc + irq; - spin_lock_irqsave(&desc->lock,flags); - p = &desc->action; - for (;;) { - struct irqaction * action = *p; - if (action) { - struct irqaction **pp = p; - p = &action->next; - if (action->dev_id != dev_id) - continue; - - /* Found - now remove it from the list of entries. */ - *pp = action->next; - if (!desc->action) { - desc->status |= IRQ_DISABLED; - desc->handler->shutdown(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - -#ifdef CONFIG_SMP - /* Wait to make sure it's not being used on - another CPU. */ - while (desc->status & IRQ_INPROGRESS) - barrier(); -#endif - kfree(action); - return; - } - printk(KERN_ERR "Trying to free free IRQ%d\n",irq); - spin_unlock_irqrestore(&desc->lock,flags); - return; - } -} - -EXPORT_SYMBOL(free_irq); - int show_interrupts(struct seq_file *p, void *v) { @@ -531,10 +144,6 @@ handle_irq(int irq, struct pt_regs * regs) * 0 return value means that this irq is already being * handled by some other CPU. (or is disabled) */ - int cpu = smp_processor_id(); - irq_desc_t *desc = irq_desc + irq; - struct irqaction * action; - unsigned int status; static unsigned int illegal_count=0; if ((unsigned) irq > ACTUAL_NR_IRQS && illegal_count < MAX_ILLEGAL_IRQS ) { @@ -546,229 +155,8 @@ handle_irq(int irq, struct pt_regs * regs) } irq_enter(); - kstat_cpu(cpu).irqs[irq]++; - spin_lock_irq(&desc->lock); /* mask also the higher prio events */ - desc->handler->ack(irq); - /* - * REPLAY is when Linux resends an IRQ that was dropped earlier. - * WAITING is used by probe to mark irqs that are being tested. - */ - status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING); - status |= IRQ_PENDING; /* we _want_ to handle it */ - - /* - * If the IRQ is disabled for whatever reason, we cannot - * use the action we have. - */ - action = NULL; - if (!(status & (IRQ_DISABLED | IRQ_INPROGRESS))) { - action = desc->action; - status &= ~IRQ_PENDING; /* we commit to handling */ - status |= IRQ_INPROGRESS; /* we are handling it */ - } - desc->status = status; - - /* - * If there is no IRQ handler or it was disabled, exit early. - * Since we set PENDING, if another processor is handling - * a different instance of this same irq, the other processor - * will take care of it. - */ - if (!action) - goto out; - - /* - * Edge triggered interrupts need to remember pending events. - * This applies to any hw interrupts that allow a second - * instance of the same irq to arrive while we are in handle_irq - * or in the handler. But the code here only handles the _second_ - * instance of the irq, not the third or fourth. So it is mostly - * useful for irq hardware that does not mask cleanly in an - * SMP environment. - */ - for (;;) { - spin_unlock(&desc->lock); - handle_IRQ_event(irq, regs, action); - spin_lock(&desc->lock); - - if (!(desc->status & IRQ_PENDING) - || (desc->status & IRQ_LEVEL)) - break; - desc->status &= ~IRQ_PENDING; - } - desc->status &= ~IRQ_INPROGRESS; -out: - /* - * The ->end() handler has to deal with interrupts which got - * disabled while the handler was running. - */ - desc->handler->end(irq); - spin_unlock(&desc->lock); - + local_irq_disable(); + __do_IRQ(irq, regs); + local_irq_enable(); irq_exit(); } - -/* - * IRQ autodetection code.. - * - * This depends on the fact that any interrupt that - * comes in on to an unassigned handler will get stuck - * with "IRQ_WAITING" cleared and the interrupt - * disabled. - */ -unsigned long -probe_irq_on(void) -{ - int i; - irq_desc_t *desc; - unsigned long delay; - unsigned long val; - - /* Something may have generated an irq long ago and we want to - flush such a longstanding irq before considering it as spurious. */ - for (i = NR_IRQS-1; i >= 0; i--) { - desc = irq_desc + i; - - spin_lock_irq(&desc->lock); - if (!irq_desc[i].action) - irq_desc[i].handler->startup(i); - spin_unlock_irq(&desc->lock); - } - - /* Wait for longstanding interrupts to trigger. */ - for (delay = jiffies + HZ/50; time_after(delay, jiffies); ) - /* about 20ms delay */ barrier(); - - /* enable any unassigned irqs (we must startup again here because - if a longstanding irq happened in the previous stage, it may have - masked itself) first, enable any unassigned irqs. */ - for (i = NR_IRQS-1; i >= 0; i--) { - desc = irq_desc + i; - - spin_lock_irq(&desc->lock); - if (!desc->action) { - desc->status |= IRQ_AUTODETECT | IRQ_WAITING; - if (desc->handler->startup(i)) - desc->status |= IRQ_PENDING; - } - spin_unlock_irq(&desc->lock); - } - - /* - * Wait for spurious interrupts to trigger - */ - for (delay = jiffies + HZ/10; time_after(delay, jiffies); ) - /* about 100ms delay */ barrier(); - - /* - * Now filter out any obviously spurious interrupts - */ - val = 0; - for (i=0; i<NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - /* It triggered already - consider it spurious. */ - if (!(status & IRQ_WAITING)) { - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } else - if (i < 32) - val |= 1 << i; - } - spin_unlock_irq(&desc->lock); - } - - return val; -} - -EXPORT_SYMBOL(probe_irq_on); - -/* - * Return a mask of triggered interrupts (this - * can handle only legacy ISA interrupts). - */ -unsigned int -probe_irq_mask(unsigned long val) -{ - int i; - unsigned int mask; - - mask = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - /* We only react to ISA interrupts */ - if (!(status & IRQ_WAITING)) { - if (i < 16) - mask |= 1 << i; - } - - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } - spin_unlock_irq(&desc->lock); - } - - return mask & val; -} - -/* - * Get the result of the IRQ probe.. A negative result means that - * we have several candidates (but we return the lowest-numbered - * one). - */ - -int -probe_irq_off(unsigned long val) -{ - int i, irq_found, nr_irqs; - - nr_irqs = 0; - irq_found = 0; - for (i=0; i<NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - if (!(status & IRQ_WAITING)) { - if (!nr_irqs) - irq_found = i; - nr_irqs++; - } - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } - spin_unlock_irq(&desc->lock); - } - - if (nr_irqs > 1) - irq_found = -irq_found; - return irq_found; -} - -EXPORT_SYMBOL(probe_irq_off); - -#ifdef CONFIG_SMP -void synchronize_irq(unsigned int irq) -{ - /* is there anything to synchronize with? */ - if (!irq_desc[irq].action) - return; - - while (irq_desc[irq].status & IRQ_INPROGRESS) - barrier(); -} -#endif |