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

	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"

 */

#ifdef CONFIG_SMP

EXPORT_SYMBOL(synchronize_irq);

EXPORT_SYMBOL(flush_tlb_mm);

EXPORT_SYMBOL(flush_tlb_range);

EXPORT_SYMBOL(flush_tlb_page);

#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;

		return 1;

	while (!cpu_possible(cpu))

		cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);

	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)

{

	 * 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 ) {

	}

	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

#include <linux/irq_cpustat.h>	/* Standard mappings for irq_cpustat_t above */

void ack_bad_irq(unsigned int irq);

#define HARDIRQ_BITS	12

/*