[deliverable/linux.git] / arch / ppc64 / kernel / irq.c

/*
 *  arch/ppc/kernel/irq.c
 *
 *  Derived from arch/i386/kernel/irq.c
 *    Copyright (C) 1992 Linus Torvalds
 *  Adapted from arch/i386 by Gary Thomas
 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 *  Updated and modified by Cort Dougan (cort@cs.nmt.edu)
 *    Copyright (C) 1996 Cort Dougan
 *  Adapted for Power Macintosh by Paul Mackerras
 *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
 *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * This file contains the code used by various IRQ handling routines:
 * asking for different IRQ's should be done through these routines
 * instead of just grabbing them. Thus setups with different IRQ numbers
 * shouldn't result in any weird surprises, and installing new handlers
 * should be easier.
 */

#include <linux/errno.h>
#include <linux/module.h>
#include <linux/threads.h>
#include <linux/kernel_stat.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/timex.h>
#include <linux/config.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/proc_fs.h>
#include <linux/random.h>
#include <linux/kallsyms.h>
#include <linux/profile.h>
#include <linux/bitops.h>

#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/cache.h>
#include <asm/prom.h>
#include <asm/ptrace.h>
#include <asm/iseries/it_lp_queue.h>
#include <asm/machdep.h>
#include <asm/paca.h>

#ifdef CONFIG_SMP
extern void iSeries_smp_message_recv( struct pt_regs * );
#endif

extern irq_desc_t irq_desc[NR_IRQS];
EXPORT_SYMBOL(irq_desc);

int distribute_irqs = 1;
int __irq_offset_value;
int ppc_spurious_interrupts;
u64 ppc64_interrupt_controller;

int show_interrupts(struct seq_file *p, void *v)
{
	int i = *(loff_t *) v, j;
	struct irqaction * action;
	irq_desc_t *desc;
	unsigned long flags;

	if (i == 0) {
		seq_printf(p, "           ");
		for (j=0; j<NR_CPUS; j++) {
			if (cpu_online(j))
				seq_printf(p, "CPU%d       ",j);
		}
		seq_putc(p, '\n');
	}

	if (i < NR_IRQS) {
		desc = get_irq_desc(i);
		spin_lock_irqsave(&desc->lock, flags);
		action = desc->action;
		if (!action || !action->handler)
			goto skip;
		seq_printf(p, "%3d: ", i);
#ifdef CONFIG_SMP
		for (j = 0; j < NR_CPUS; j++) {
			if (cpu_online(j))
				seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
		}
#else
		seq_printf(p, "%10u ", kstat_irqs(i));
#endif /* CONFIG_SMP */
		if (desc->handler)
			seq_printf(p, " %s ", desc->handler->typename );
		else
			seq_printf(p, "  None      ");
		seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
		seq_printf(p, "    %s",action->name);
		for (action=action->next; action; action = action->next)
			seq_printf(p, ", %s", action->name);
		seq_putc(p, '\n');
skip:
		spin_unlock_irqrestore(&desc->lock, flags);
	} else if (i == NR_IRQS)
		seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
	return 0;
}

#ifdef CONFIG_HOTPLUG_CPU
void fixup_irqs(cpumask_t map)
{
	unsigned int irq;
	static int warned;

	for_each_irq(irq) {
		cpumask_t mask;

		if (irq_desc[irq].status & IRQ_PER_CPU)
			continue;

		cpus_and(mask, irq_affinity[irq], map);
		if (any_online_cpu(mask) == NR_CPUS) {
			printk("Breaking affinity for irq %i\n", irq);
			mask = map;
		}
		if (irq_desc[irq].handler->set_affinity)
			irq_desc[irq].handler->set_affinity(irq, mask);
		else if (irq_desc[irq].action && !(warned++))
			printk("Cannot set affinity for irq %i\n", irq);
	}

	local_irq_enable();
	mdelay(1);
	local_irq_disable();
}
#endif

extern int noirqdebug;

/*
 * Eventually, this should take an array of interrupts and an array size
 * so it can dispatch multiple interrupts.
 */
void ppc_irq_dispatch_handler(struct pt_regs *regs, int irq)
{
	int status;
	struct irqaction *action;
	int cpu = smp_processor_id();
	irq_desc_t *desc = get_irq_desc(irq);
	irqreturn_t action_ret;
#ifdef CONFIG_IRQSTACKS
	struct thread_info *curtp, *irqtp;
#endif

	kstat_cpu(cpu).irqs[irq]++;

	if (desc->status & IRQ_PER_CPU) {
		/* no locking required for CPU-local interrupts: */
		ack_irq(irq);
		action_ret = handle_IRQ_event(irq, regs, desc->action);
		desc->handler->end(irq);
		return;
	}

	spin_lock(&desc->lock);
	ack_irq(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 (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) {
		action = desc->action;
		if (!action || !action->handler) {
			ppc_spurious_interrupts++;
			printk(KERN_DEBUG "Unhandled interrupt %x, disabled\n", irq);
			/* We can't call disable_irq here, it would deadlock */
			if (!desc->depth)
				desc->depth = 1;
			desc->status |= IRQ_DISABLED;
			/* This is not a real spurrious interrupt, we
			 * have to eoi it, so we jump to out
			 */
			mask_irq(irq);
			goto out;
		}
		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 (unlikely(!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 do_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);

#ifdef CONFIG_IRQSTACKS
		/* Switch to the irq stack to handle this */
		curtp = current_thread_info();
		irqtp = hardirq_ctx[smp_processor_id()];
		if (curtp != irqtp) {
			irqtp->task = curtp->task;
			irqtp->flags = 0;
			action_ret = call_handle_IRQ_event(irq, regs, action, irqtp);
			irqtp->task = NULL;
			if (irqtp->flags)
				set_bits(irqtp->flags, &curtp->flags);
		} else
#endif
			action_ret = handle_IRQ_event(irq, regs, action);

		spin_lock(&desc->lock);
		if (!noirqdebug)
			note_interrupt(irq, desc, action_ret, regs);
		if (likely(!(desc->status & IRQ_PENDING)))
			break;
		desc->status &= ~IRQ_PENDING;
	}
out:
	desc->status &= ~IRQ_INPROGRESS;
	/*
	 * The ->end() handler has to deal with interrupts which got
	 * disabled while the handler was running.
	 */
	if (desc->handler) {
		if (desc->handler->end)
			desc->handler->end(irq);
		else if (desc->handler->enable)
			desc->handler->enable(irq);
	}
	spin_unlock(&desc->lock);
}

#ifdef CONFIG_PPC_ISERIES
void do_IRQ(struct pt_regs *regs)
{
	struct paca_struct *lpaca;

	irq_enter();

#ifdef CONFIG_DEBUG_STACKOVERFLOW
	/* Debugging check for stack overflow: is there less than 2KB free? */
	{
		long sp;

		sp = __get_SP() & (THREAD_SIZE-1);

		if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
			printk("do_IRQ: stack overflow: %ld\n",
				sp - sizeof(struct thread_info));
			dump_stack();
		}
	}
#endif

	lpaca = get_paca();
#ifdef CONFIG_SMP
	if (lpaca->lppaca.int_dword.fields.ipi_cnt) {
		lpaca->lppaca.int_dword.fields.ipi_cnt = 0;
		iSeries_smp_message_recv(regs);
	}
#endif /* CONFIG_SMP */
	if (hvlpevent_is_pending())
		process_hvlpevents(regs);

	irq_exit();

	if (lpaca->lppaca.int_dword.fields.decr_int) {
		lpaca->lppaca.int_dword.fields.decr_int = 0;
		/* Signal a fake decrementer interrupt */
		timer_interrupt(regs);
	}
}

#else	/* CONFIG_PPC_ISERIES */

void do_IRQ(struct pt_regs *regs)
{
	int irq;

	irq_enter();

#ifdef CONFIG_DEBUG_STACKOVERFLOW
	/* Debugging check for stack overflow: is there less than 2KB free? */
	{
		long sp;

		sp = __get_SP() & (THREAD_SIZE-1);

		if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
			printk("do_IRQ: stack overflow: %ld\n",
				sp - sizeof(struct thread_info));
			dump_stack();
		}
	}
#endif

	irq = ppc_md.get_irq(regs);

	if (irq >= 0)
		ppc_irq_dispatch_handler(regs, irq);
	else
		/* That's not SMP safe ... but who cares ? */
		ppc_spurious_interrupts++;

	irq_exit();
}
#endif	/* CONFIG_PPC_ISERIES */

void __init init_IRQ(void)
{
	static int once = 0;

	if (once)
		return;

	once++;

	ppc_md.init_IRQ();
	irq_ctx_init();
}

#ifndef CONFIG_PPC_ISERIES
/*
 * Virtual IRQ mapping code, used on systems with XICS interrupt controllers.
 */

#define UNDEFINED_IRQ 0xffffffff
unsigned int virt_irq_to_real_map[NR_IRQS];

/*
 * Don't use virtual irqs 0, 1, 2 for devices.
 * The pcnet32 driver considers interrupt numbers < 2 to be invalid,
 * and 2 is the XICS IPI interrupt.
 * We limit virtual irqs to 17 less than NR_IRQS so that when we
 * offset them by 16 (to reserve the first 16 for ISA interrupts)
 * we don't end up with an interrupt number >= NR_IRQS.
 */
#define MIN_VIRT_IRQ	3
#define MAX_VIRT_IRQ	(NR_IRQS - NUM_ISA_INTERRUPTS - 1)
#define NR_VIRT_IRQS	(MAX_VIRT_IRQ - MIN_VIRT_IRQ + 1)

void
virt_irq_init(void)
{
	int i;
	for (i = 0; i < NR_IRQS; i++)
		virt_irq_to_real_map[i] = UNDEFINED_IRQ;
}

/* Create a mapping for a real_irq if it doesn't already exist.
 * Return the virtual irq as a convenience.
 */
int virt_irq_create_mapping(unsigned int real_irq)
{
	unsigned int virq, first_virq;
	static int warned;

	if (ppc64_interrupt_controller == IC_OPEN_PIC)
		return real_irq;	/* no mapping for openpic (for now) */

	if (ppc64_interrupt_controller == IC_CELL_PIC)
		return real_irq;	/* no mapping for iic either */

	/* don't map interrupts < MIN_VIRT_IRQ */
	if (real_irq < MIN_VIRT_IRQ) {
		virt_irq_to_real_map[real_irq] = real_irq;
		return real_irq;
	}

	/* map to a number between MIN_VIRT_IRQ and MAX_VIRT_IRQ */
	virq = real_irq;
	if (virq > MAX_VIRT_IRQ)
		virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ;

	/* search for this number or a free slot */
	first_virq = virq;
	while (virt_irq_to_real_map[virq] != UNDEFINED_IRQ) {
		if (virt_irq_to_real_map[virq] == real_irq)
			return virq;
		if (++virq > MAX_VIRT_IRQ)
			virq = MIN_VIRT_IRQ;
		if (virq == first_virq)
			goto nospace;	/* oops, no free slots */
	}

	virt_irq_to_real_map[virq] = real_irq;
	return virq;

 nospace:
	if (!warned) {
		printk(KERN_CRIT "Interrupt table is full\n");
		printk(KERN_CRIT "Increase NR_IRQS (currently %d) "
		       "in your kernel sources and rebuild.\n", NR_IRQS);
		warned = 1;
	}
	return NO_IRQ;
}

/*
 * In most cases will get a hit on the very first slot checked in the
 * virt_irq_to_real_map.  Only when there are a large number of
 * IRQs will this be expensive.
 */
unsigned int real_irq_to_virt_slowpath(unsigned int real_irq)
{
	unsigned int virq;
	unsigned int first_virq;

	virq = real_irq;

	if (virq > MAX_VIRT_IRQ)
		virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ;

	first_virq = virq;

	do {
		if (virt_irq_to_real_map[virq] == real_irq)
			return virq;

		virq++;

		if (virq >= MAX_VIRT_IRQ)
			virq = 0;

	} while (first_virq != virq);

	return NO_IRQ;

}

#endif /* CONFIG_PPC_ISERIES */

#ifdef CONFIG_IRQSTACKS
struct thread_info *softirq_ctx[NR_CPUS];
struct thread_info *hardirq_ctx[NR_CPUS];

void irq_ctx_init(void)
{
	struct thread_info *tp;
	int i;

	for_each_cpu(i) {
		memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
		tp = softirq_ctx[i];
		tp->cpu = i;
		tp->preempt_count = SOFTIRQ_OFFSET;

		memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
		tp = hardirq_ctx[i];
		tp->cpu = i;
		tp->preempt_count = HARDIRQ_OFFSET;
	}
}

void do_softirq(void)
{
	unsigned long flags;
	struct thread_info *curtp, *irqtp;

	if (in_interrupt())
		return;

	local_irq_save(flags);

	if (local_softirq_pending()) {
		curtp = current_thread_info();
		irqtp = softirq_ctx[smp_processor_id()];
		irqtp->task = curtp->task;
		call_do_softirq(irqtp);
		irqtp->task = NULL;
	}

	local_irq_restore(flags);
}
EXPORT_SYMBOL(do_softirq);

#endif /* CONFIG_IRQSTACKS */

static int __init setup_noirqdistrib(char *str)
{
	distribute_irqs = 0;
	return 1;
}

__setup("noirqdistrib", setup_noirqdistrib);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* arch/ppc/kernel/irq.c
	3	*
	4	* Derived from arch/i386/kernel/irq.c
	5	* Copyright (C) 1992 Linus Torvalds
	6	* Adapted from arch/i386 by Gary Thomas
	7	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	8	* Updated and modified by Cort Dougan (cort@cs.nmt.edu)
	9	* Copyright (C) 1996 Cort Dougan
	10	* Adapted for Power Macintosh by Paul Mackerras
	11	* Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
	12	* Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
	13	*
	14	* This program is free software; you can redistribute it and/or
	15	* modify it under the terms of the GNU General Public License
	16	* as published by the Free Software Foundation; either version
	17	* 2 of the License, or (at your option) any later version.
	18	*
	19	* This file contains the code used by various IRQ handling routines:
	20	* asking for different IRQ's should be done through these routines
	21	* instead of just grabbing them. Thus setups with different IRQ numbers
	22	* shouldn't result in any weird surprises, and installing new handlers
	23	* should be easier.
	24	*/
	25
	26	#include <linux/errno.h>
	27	#include <linux/module.h>
	28	#include <linux/threads.h>
	29	#include <linux/kernel_stat.h>
	30	#include <linux/signal.h>
	31	#include <linux/sched.h>
	32	#include <linux/ioport.h>
	33	#include <linux/interrupt.h>
	34	#include <linux/timex.h>
	35	#include <linux/config.h>
	36	#include <linux/init.h>
	37	#include <linux/slab.h>
	38	#include <linux/pci.h>
	39	#include <linux/delay.h>
	40	#include <linux/irq.h>
	41	#include <linux/proc_fs.h>
	42	#include <linux/random.h>
	43	#include <linux/kallsyms.h>
	44	#include <linux/profile.h>
	45	#include <linux/bitops.h>
	46
	47	#include <asm/uaccess.h>
	48	#include <asm/system.h>
	49	#include <asm/io.h>
	50	#include <asm/pgtable.h>
	51	#include <asm/irq.h>
	52	#include <asm/cache.h>
	53	#include <asm/prom.h>
	54	#include <asm/ptrace.h>
8875ccfb	55	#include <asm/iseries/it_lp_queue.h>
1da177e4 LT	56	#include <asm/machdep.h>
	57	#include <asm/paca.h>
	58
	59	#ifdef CONFIG_SMP
	60	extern void iSeries_smp_message_recv( struct pt_regs * );
	61	#endif
	62
	63	extern irq_desc_t irq_desc[NR_IRQS];
	64	EXPORT_SYMBOL(irq_desc);
	65
	66	int distribute_irqs = 1;
	67	int __irq_offset_value;
	68	int ppc_spurious_interrupts;
1da177e4 LT	69	u64 ppc64_interrupt_controller;
	70
	71	int show_interrupts(struct seq_file p, void v)
	72	{
	73	int i = (loff_t ) v, j;
	74	struct irqaction * action;
	75	irq_desc_t *desc;
	76	unsigned long flags;
	77
	78	if (i == 0) {
	79	seq_printf(p, " ");
	80	for (j=0; j<NR_CPUS; j++) {
	81	if (cpu_online(j))
	82	seq_printf(p, "CPU%d ",j);
	83	}
	84	seq_putc(p, '\n');
	85	}
	86
	87	if (i < NR_IRQS) {
	88	desc = get_irq_desc(i);
	89	spin_lock_irqsave(&desc->lock, flags);
	90	action = desc->action;
	91	if (!action \|\| !action->handler)
	92	goto skip;
	93	seq_printf(p, "%3d: ", i);
	94	#ifdef CONFIG_SMP
	95	for (j = 0; j < NR_CPUS; j++) {
	96	if (cpu_online(j))
	97	seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
	98	}
	99	#else
	100	seq_printf(p, "%10u ", kstat_irqs(i));
	101	#endif /* CONFIG_SMP */
	102	if (desc->handler)
	103	seq_printf(p, " %s ", desc->handler->typename );
	104	else
	105	seq_printf(p, " None ");
	106	seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge ");
	107	seq_printf(p, " %s",action->name);
	108	for (action=action->next; action; action = action->next)
	109	seq_printf(p, ", %s", action->name);
	110	seq_putc(p, '\n');
	111	skip:
	112	spin_unlock_irqrestore(&desc->lock, flags);
	113	} else if (i == NR_IRQS)
	114	seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
	115	return 0;
	116	}
	117
	118	#ifdef CONFIG_HOTPLUG_CPU
	119	void fixup_irqs(cpumask_t map)
	120	{
	121	unsigned int irq;
	122	static int warned;
	123
	124	for_each_irq(irq) {
	125	cpumask_t mask;
	126
	127	if (irq_desc[irq].status & IRQ_PER_CPU)
	128	continue;
	129
	130	cpus_and(mask, irq_affinity[irq], map);
	131	if (any_online_cpu(mask) == NR_CPUS) {
	132	printk("Breaking affinity for irq %i\n", irq);
133	mask = map;
134	}
135	if (irq_desc[irq].handler->set_affinity)
136	irq_desc[irq].handler->set_affinity(irq, mask);
137	else if (irq_desc[irq].action && !(warned++))
138	printk("Cannot set affinity for irq %i\n", irq);
139	}
140
141	local_irq_enable();
142	mdelay(1);
143	local_irq_disable();
144	}
145	#endif
146
147	extern int noirqdebug;
148
149	/*
150	* Eventually, this should take an array of interrupts and an array size
151	* so it can dispatch multiple interrupts.
152	*/
153	void ppc_irq_dispatch_handler(struct pt_regs *regs, int irq)
154	{
155	int status;
156	struct irqaction *action;
157	int cpu = smp_processor_id();
158	irq_desc_t *desc = get_irq_desc(irq);
159	irqreturn_t action_ret;
160	#ifdef CONFIG_IRQSTACKS
161	struct thread_info curtp, irqtp;
162	#endif
163
164	kstat_cpu(cpu).irqs[irq]++;
165
166	if (desc->status & IRQ_PER_CPU) {
167	/* no locking required for CPU-local interrupts: */
168	ack_irq(irq);
169	action_ret = handle_IRQ_event(irq, regs, desc->action);
170	desc->handler->end(irq);
171	return;
172	}
173
174	spin_lock(&desc->lock);
175	ack_irq(irq);
176	/*
177	REPLAY is when Linux resends an IRQ that was dropped earlier
178	WAITING is used by probe to mark irqs that are being tested
179	*/
180	status = desc->status & ~(IRQ_REPLAY \| IRQ_WAITING);
181	status \|= IRQ_PENDING; /* we _want_ to handle it */
182
183	/*
184	* If the IRQ is disabled for whatever reason, we cannot
185	* use the action we have.
186	*/
187	action = NULL;
188	if (likely(!(status & (IRQ_DISABLED \| IRQ_INPROGRESS)))) {
189	action = desc->action;
190	if (!action \|\| !action->handler) {
191	ppc_spurious_interrupts++;
192	printk(KERN_DEBUG "Unhandled interrupt %x, disabled\n", irq);
193	/* We can't call disable_irq here, it would deadlock */
194	if (!desc->depth)
195	desc->depth = 1;
196	desc->status \|= IRQ_DISABLED;
197	/* This is not a real spurrious interrupt, we
198	* have to eoi it, so we jump to out
199	*/
200	mask_irq(irq);
201	goto out;
202	}
203	status &= ~IRQ_PENDING; /* we commit to handling */
204	status \|= IRQ_INPROGRESS; /* we are handling it */
205	}
206	desc->status = status;
207
208	/*
209	* If there is no IRQ handler or it was disabled, exit early.
210	Since we set PENDING, if another processor is handling
211	a different instance of this same irq, the other processor
212	will take care of it.
213	*/
214	if (unlikely(!action))
215	goto out;
216
217	/*
218	* Edge triggered interrupts need to remember
219	* pending events.
220	* This applies to any hw interrupts that allow a second
221	* instance of the same irq to arrive while we are in do_IRQ
222	* or in the handler. But the code here only handles the _second_
223	* instance of the irq, not the third or fourth. So it is mostly
224	* useful for irq hardware that does not mask cleanly in an
225	* SMP environment.
226	*/
227	for (;;) {
228	spin_unlock(&desc->lock);
229
230	#ifdef CONFIG_IRQSTACKS
231	/* Switch to the irq stack to handle this */
232	curtp = current_thread_info();
233	irqtp = hardirq_ctx[smp_processor_id()];
234	if (curtp != irqtp) {
235	irqtp->task = curtp->task;
236	irqtp->flags = 0;
237	action_ret = call_handle_IRQ_event(irq, regs, action, irqtp);
238	irqtp->task = NULL;
239	if (irqtp->flags)
240	set_bits(irqtp->flags, &curtp->flags);
241	} else
242	#endif
243	action_ret = handle_IRQ_event(irq, regs, action);
244
245	spin_lock(&desc->lock);
246	if (!noirqdebug)
200803df	247	note_interrupt(irq, desc, action_ret, regs);
1da177e4 LT	248	if (likely(!(desc->status & IRQ_PENDING)))
	249	break;
	250	desc->status &= ~IRQ_PENDING;
	251	}
	252	out:
	253	desc->status &= ~IRQ_INPROGRESS;
	254	/*
	255	* The ->end() handler has to deal with interrupts which got
	256	* disabled while the handler was running.
	257	*/
	258	if (desc->handler) {
	259	if (desc->handler->end)
	260	desc->handler->end(irq);
	261	else if (desc->handler->enable)
	262	desc->handler->enable(irq);
	263	}
	264	spin_unlock(&desc->lock);
	265	}
	266
	267	#ifdef CONFIG_PPC_ISERIES
	268	void do_IRQ(struct pt_regs *regs)
	269	{
	270	struct paca_struct *lpaca;
1da177e4 LT	271
	272	irq_enter();
	273
	274	#ifdef CONFIG_DEBUG_STACKOVERFLOW
	275	/* Debugging check for stack overflow: is there less than 2KB free? */
	276	{
	277	long sp;
	278
	279	sp = __get_SP() & (THREAD_SIZE-1);
	280
	281	if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
	282	printk("do_IRQ: stack overflow: %ld\n",
	283	sp - sizeof(struct thread_info));
	284	dump_stack();
	285	}
	286	}
	287	#endif
	288
	289	lpaca = get_paca();
	290	#ifdef CONFIG_SMP
	291	if (lpaca->lppaca.int_dword.fields.ipi_cnt) {
	292	lpaca->lppaca.int_dword.fields.ipi_cnt = 0;
	293	iSeries_smp_message_recv(regs);
	294	}
	295	#endif /* CONFIG_SMP */
937b31b1	296	if (hvlpevent_is_pending())
74889802	297	process_hvlpevents(regs);
1da177e4 LT	298
	299	irq_exit();
	300
	301	if (lpaca->lppaca.int_dword.fields.decr_int) {
	302	lpaca->lppaca.int_dword.fields.decr_int = 0;
	303	/* Signal a fake decrementer interrupt */
	304	timer_interrupt(regs);
	305	}
	306	}
	307
	308	#else /* CONFIG_PPC_ISERIES */
	309
	310	void do_IRQ(struct pt_regs *regs)
	311	{
	312	int irq;
	313
	314	irq_enter();
	315
	316	#ifdef CONFIG_DEBUG_STACKOVERFLOW
	317	/* Debugging check for stack overflow: is there less than 2KB free? */
	318	{
	319	long sp;
	320
	321	sp = __get_SP() & (THREAD_SIZE-1);
	322
	323	if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
	324	printk("do_IRQ: stack overflow: %ld\n",
	325	sp - sizeof(struct thread_info));
	326	dump_stack();
	327	}
	328	}
	329	#endif
	330
	331	irq = ppc_md.get_irq(regs);
	332
	333	if (irq >= 0)
	334	ppc_irq_dispatch_handler(regs, irq);
	335	else
	336	/* That's not SMP safe ... but who cares ? */
	337	ppc_spurious_interrupts++;
	338
	339	irq_exit();
	340	}
	341	#endif /* CONFIG_PPC_ISERIES */
	342
	343	void __init init_IRQ(void)
	344	{
	345	static int once = 0;
	346
	347	if (once)
	348	return;
	349
	350	once++;
	351
	352	ppc_md.init_IRQ();
	353	irq_ctx_init();
	354	}
	355
	356	#ifndef CONFIG_PPC_ISERIES
	357	/*
	358	* Virtual IRQ mapping code, used on systems with XICS interrupt controllers.
	359	*/
	360
	361	#define UNDEFINED_IRQ 0xffffffff
362	unsigned int virt_irq_to_real_map[NR_IRQS];
363
364	/*
365	* Don't use virtual irqs 0, 1, 2 for devices.
366	* The pcnet32 driver considers interrupt numbers < 2 to be invalid,
367	* and 2 is the XICS IPI interrupt.
368	* We limit virtual irqs to 17 less than NR_IRQS so that when we
369	* offset them by 16 (to reserve the first 16 for ISA interrupts)
370	* we don't end up with an interrupt number >= NR_IRQS.
371	*/
372	#define MIN_VIRT_IRQ 3
373	#define MAX_VIRT_IRQ (NR_IRQS - NUM_ISA_INTERRUPTS - 1)
374	#define NR_VIRT_IRQS (MAX_VIRT_IRQ - MIN_VIRT_IRQ + 1)
375
376	void
377	virt_irq_init(void)
378	{
379	int i;
380	for (i = 0; i < NR_IRQS; i++)
381	virt_irq_to_real_map[i] = UNDEFINED_IRQ;
382	}
383
384	/* Create a mapping for a real_irq if it doesn't already exist.
385	* Return the virtual irq as a convenience.
386	*/
387	int virt_irq_create_mapping(unsigned int real_irq)
388	{
389	unsigned int virq, first_virq;
390	static int warned;
391
392	if (ppc64_interrupt_controller == IC_OPEN_PIC)
393	return real_irq; /* no mapping for openpic (for now) */
394
f3f66f59	395	if (ppc64_interrupt_controller == IC_CELL_PIC)
fef1c772 AB	396	return real_irq; /* no mapping for iic either */
fef1c772 AB	397
1da177e4 LT	398	/* don't map interrupts < MIN_VIRT_IRQ */
	399	if (real_irq < MIN_VIRT_IRQ) {
	400	virt_irq_to_real_map[real_irq] = real_irq;
	401	return real_irq;
	402	}
	403
	404	/* map to a number between MIN_VIRT_IRQ and MAX_VIRT_IRQ */
	405	virq = real_irq;
	406	if (virq > MAX_VIRT_IRQ)
	407	virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ;
	408
	409	/* search for this number or a free slot */
	410	first_virq = virq;
	411	while (virt_irq_to_real_map[virq] != UNDEFINED_IRQ) {
	412	if (virt_irq_to_real_map[virq] == real_irq)
	413	return virq;
	414	if (++virq > MAX_VIRT_IRQ)
	415	virq = MIN_VIRT_IRQ;
	416	if (virq == first_virq)
	417	goto nospace; /* oops, no free slots */
	418	}
	419
	420	virt_irq_to_real_map[virq] = real_irq;
	421	return virq;
	422
	423	nospace:
	424	if (!warned) {
	425	printk(KERN_CRIT "Interrupt table is full\n");
	426	printk(KERN_CRIT "Increase NR_IRQS (currently %d) "
	427	"in your kernel sources and rebuild.\n", NR_IRQS);
	428	warned = 1;
	429	}
	430	return NO_IRQ;
	431	}
	432
	433	/*
	434	* In most cases will get a hit on the very first slot checked in the
	435	* virt_irq_to_real_map. Only when there are a large number of
	436	* IRQs will this be expensive.
	437	*/
	438	unsigned int real_irq_to_virt_slowpath(unsigned int real_irq)
	439	{
	440	unsigned int virq;
	441	unsigned int first_virq;
	442
	443	virq = real_irq;
	444
	445	if (virq > MAX_VIRT_IRQ)
	446	virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ;
	447
	448	first_virq = virq;
	449
	450	do {
	451	if (virt_irq_to_real_map[virq] == real_irq)
	452	return virq;
	453
	454	virq++;
	455
	456	if (virq >= MAX_VIRT_IRQ)
	457	virq = 0;
	458
	459	} while (first_virq != virq);
	460
	461	return NO_IRQ;
462
463	}
464
465	#endif /* CONFIG_PPC_ISERIES */
466
467	#ifdef CONFIG_IRQSTACKS
468	struct thread_info *softirq_ctx[NR_CPUS];
469	struct thread_info *hardirq_ctx[NR_CPUS];
470
471	void irq_ctx_init(void)
472	{
473	struct thread_info *tp;
474	int i;
475
476	for_each_cpu(i) {
477	memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
478	tp = softirq_ctx[i];
479	tp->cpu = i;
480	tp->preempt_count = SOFTIRQ_OFFSET;
481
482	memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
483	tp = hardirq_ctx[i];
484	tp->cpu = i;
485	tp->preempt_count = HARDIRQ_OFFSET;
486	}
487	}
488
489	void do_softirq(void)
490	{
491	unsigned long flags;
492	struct thread_info curtp, irqtp;
493
494	if (in_interrupt())
495	return;
496
497	local_irq_save(flags);
498
499	if (local_softirq_pending()) {
500	curtp = current_thread_info();
501	irqtp = softirq_ctx[smp_processor_id()];
502	irqtp->task = curtp->task;
503	call_do_softirq(irqtp);
504	irqtp->task = NULL;
505	}
506
507	local_irq_restore(flags);
508	}
509	EXPORT_SYMBOL(do_softirq);
510
511	#endif /* CONFIG_IRQSTACKS */
512
513	static int __init setup_noirqdistrib(char *str)
514	{
515	distribute_irqs = 0;
516	return 1;
517	}
518
519	__setup("noirqdistrib", setup_noirqdistrib);