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-rw-r--r--arch/alpha/kernel/irq.c630
1 files changed, 9 insertions, 621 deletions
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c
index b6114f5c0d2b..76be5cf0de13 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