[PATCH] Alpha: convert to generic irq framework (alpha part)

Kconfig tweaks and tons of deletions.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 24 insertions, 622 deletions

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 786491f9ceb2..153337ff1d7b 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -40,6 +40,19 @@ config GENERIC_IOMAP
 	bool
 	default n
 
+config GENERIC_HARDIRQS
+	bool
+	default y
+
+config GENERIC_IRQ_PROBE
+	bool
+	default y
+
+config AUTO_IRQ_AFFINITY
+	bool
+	depends on SMP
+	default y
+
 source "init/Kconfig"
 
 
diff --git a/arch/alpha/kernel/alpha_ksyms.c b/arch/alpha/kernel/alpha_ksyms.c
index 24ae9a366073..f3e98f837784 100644
--- a/arch/alpha/kernel/alpha_ksyms.c
+++ b/arch/alpha/kernel/alpha_ksyms.c
@@ -175,7 +175,6 @@ EXPORT_SYMBOL(up);
  */
 
 #ifdef CONFIG_SMP
-EXPORT_SYMBOL(synchronize_irq);
 EXPORT_SYMBOL(flush_tlb_mm);
 EXPORT_SYMBOL(flush_tlb_range);
 EXPORT_SYMBOL(flush_tlb_page);
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
diff --git a/include/asm-alpha/hardirq.h b/include/asm-alpha/hardirq.h
index c0593f9b21e1..7bb6a36c96a1 100644
--- a/include/asm-alpha/hardirq.h
+++ b/include/asm-alpha/hardirq.h
@@ -13,6 +13,8 @@ typedef struct {
 
 #include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */
 
+void ack_bad_irq(unsigned int irq);
+
 #define HARDIRQ_BITS	12
 
 /*